1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
5383
5384
5385
5386
5387
5388
5389
5390
5391
5392
5393
5394
5395
5396
5397
5398
5399
5400
5401
5402
5403
5404
5405
5406
5407
5408
5409
5410
5411
5412
5413
5414
5415
5416
5417
5418
5419
5420
5421
5422
5423
5424
5425
5426
5427
5428
5429
5430
5431
5432
5433
5434
5435
5436
5437
5438
5439
5440
5441
5442
5443
5444
5445
5446
5447
5448
5449
5450
5451
5452
5453
5454
5455
5456
5457
5458
5459
5460
5461
5462
5463
5464
5465
5466
5467
5468
5469
5470
5471
5472
5473
5474
5475
5476
5477
5478
5479
5480
5481
5482
5483
5484
5485
5486
5487
5488
5489
5490
5491
5492
5493
5494
5495
5496
5497
5498
5499
5500
5501
5502
5503
5504
5505
5506
5507
5508
5509
5510
5511
5512
5513
5514
5515
5516
5517
5518
5519
5520
5521
5522
5523
5524
5525
5526
5527
5528
5529
5530
5531
5532
5533
5534
5535
5536
5537
5538
5539
5540
5541
5542
5543
5544
5545
5546
5547
5548
5549
5550
5551
5552
5553
5554
5555
5556
5557
5558
5559
5560
5561
5562
5563
5564
5565
5566
5567
5568
5569
5570
5571
5572
5573
5574
5575
5576
5577
5578
5579
5580
5581
5582
5583
5584
5585
5586
5587
5588
5589
5590
5591
5592
5593
5594
5595
5596
5597
5598
5599
5600
5601
5602
5603
5604
5605
5606
5607
5608
5609
5610
5611
5612
5613
5614
5615
5616
5617
5618
5619
5620
5621
5622
5623
5624
5625
5626
5627
5628
5629
5630
5631
5632
5633
5634
5635
5636
5637
5638
5639
5640
5641
5642
5643
5644
5645
5646
5647
5648
5649
5650
5651
5652
5653
5654
5655
5656
5657
5658
5659
5660
5661
5662
5663
5664
5665
5666
5667
5668
5669
5670
5671
5672
5673
5674
5675
5676
5677
5678
5679
5680
5681
5682
5683
5684
5685
5686
5687
5688
5689
5690
5691
5692
5693
5694
5695
5696
5697
5698
5699
5700
5701
5702
5703
5704
5705
5706
5707
5708
5709
5710
5711
5712
5713
5714
5715
5716
5717
5718
5719
5720
5721
5722
5723
5724
5725
5726
5727
5728
5729
5730
5731
5732
5733
5734
5735
5736
5737
5738
5739
5740
5741
5742
5743
5744
5745
5746
5747
5748
5749
5750
5751
5752
5753
5754
5755
5756
5757
5758
5759
5760
5761
5762
5763
5764
5765
5766
5767
5768
5769
5770
5771
5772
5773
5774
5775
5776
5777
5778
5779
5780
5781
5782
5783
5784
5785
5786
5787
5788
5789
5790
5791
5792
5793
5794
5795
5796
5797
5798
5799
5800
5801
5802
5803
5804
5805
5806
5807
5808
5809
5810
5811
5812
5813
5814
5815
5816
5817
5818
5819
5820
5821
5822
5823
5824
5825
5826
5827
5828
5829
5830
5831
5832
5833
5834
5835
5836
5837
5838
5839
5840
5841
5842
5843
5844
5845
5846
5847
5848
5849
5850
5851
5852
5853
5854
5855
5856
5857
5858
5859
5860
5861
5862
5863
5864
5865
5866
5867
5868
5869
5870
5871
5872
5873
5874
5875
5876
5877
5878
5879
5880
5881
5882
5883
5884
5885
5886
5887
5888
5889
5890
5891
5892
5893
5894
5895
5896
5897
5898
5899
5900
5901
5902
5903
5904
5905
5906
5907
5908
5909
5910
5911
5912
5913
5914
5915
5916
5917
5918
5919
5920
5921
5922
5923
5924
5925
5926
5927
5928
5929
5930
5931
5932
5933
5934
5935
5936
5937
5938
5939
5940
5941
5942
5943
5944
5945
5946
5947
5948
5949
5950
5951
5952
5953
5954
5955
5956
5957
5958
5959
5960
5961
5962
5963
5964
5965
5966
5967
5968
5969
5970
5971
5972
5973
5974
5975
5976
5977
5978
5979
5980
5981
5982
5983
5984
5985
5986
5987
5988
5989
5990
5991
5992
5993
5994
5995
5996
5997
5998
5999
6000
6001
6002
6003
6004
6005
6006
6007
6008
6009
6010
6011
6012
6013
6014
6015
6016
6017
6018
6019
6020
6021
6022
6023
6024
6025
6026
6027
6028
6029
6030
6031
6032
6033
6034
6035
6036
6037
6038
6039
6040
6041
6042
6043
6044
6045
6046
6047
6048
6049
6050
6051
6052
6053
6054
6055
6056
6057
6058
6059
6060
6061
6062
6063
6064
6065
6066
6067
6068
6069
6070
6071
6072
6073
6074
6075
6076
6077
6078
6079
6080
6081
6082
6083
6084
6085
6086
6087
6088
6089
6090
6091
6092
6093
6094
6095
6096
6097
6098
6099
6100
6101
6102
6103
6104
|
# Crypto
<!--introduced_in=v0.3.6-->
> Stability: 2 - Stable
<!-- source_link=lib/crypto.js -->
The `crypto` module provides cryptographic functionality that includes a set of
wrappers for OpenSSL's hash, HMAC, cipher, decipher, sign, and verify functions.
```mjs
const { createHmac } = await import('crypto');
const secret = 'abcdefg';
const hash = createHmac('sha256', secret)
.update('I love cupcakes')
.digest('hex');
console.log(hash);
// Prints:
// c0fa1bc00531bd78ef38c628449c5102aeabd49b5dc3a2a516ea6ea959d6658e
```
```cjs
const crypto = require('crypto');
const secret = 'abcdefg';
const hash = crypto.createHmac('sha256', secret)
.update('I love cupcakes')
.digest('hex');
console.log(hash);
// Prints:
// c0fa1bc00531bd78ef38c628449c5102aeabd49b5dc3a2a516ea6ea959d6658e
```
## Determining if crypto support is unavailable
It is possible for Node.js to be built without including support for the
`crypto` module. In such cases, attempting to `import` from `crypto` or
calling `require('crypto')` will result in an error being thrown.
When using CommonJS, the error thrown can be caught using try/catch:
```cjs
let crypto;
try {
crypto = require('crypto');
} catch (err) {
console.log('crypto support is disabled!');
}
```
When using the lexical ESM `import` keyword, the error can only be
caught if a handler for `process.on('uncaughtException')` is registered
_before_ any attempt to load the module is made -- using, for instance,
a preload module.
When using ESM, if there is a chance that the code may be run on a build
of Node.js where crypto support is not enabled, consider using the
`import()` function instead of the lexical `import` keyword:
```mjs
let crypto;
try {
crypto = await import('crypto');
} catch (err) {
console.log('crypto support is disabled!');
}
```
## Class: `Certificate`
<!-- YAML
added: v0.11.8
-->
SPKAC is a Certificate Signing Request mechanism originally implemented by
Netscape and was specified formally as part of [HTML5's `keygen` element][].
`<keygen>` is deprecated since [HTML 5.2][] and new projects
should not use this element anymore.
The `crypto` module provides the `Certificate` class for working with SPKAC
data. The most common usage is handling output generated by the HTML5
`<keygen>` element. Node.js uses [OpenSSL's SPKAC implementation][] internally.
### Static method: `Certificate.exportChallenge(spkac[, encoding])`
<!-- YAML
added: v9.0.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The spkac argument can be an ArrayBuffer. Limited the size of
the spkac argument to a maximum of 2**31 - 1 bytes.
-->
* `spkac` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `spkac` string.
* Returns: {Buffer} The challenge component of the `spkac` data structure, which
includes a public key and a challenge.
```mjs
const { Certificate } = await import('crypto');
const spkac = getSpkacSomehow();
const challenge = Certificate.exportChallenge(spkac);
console.log(challenge.toString('utf8'));
// Prints: the challenge as a UTF8 string
```
```cjs
const { Certificate } = require('crypto');
const spkac = getSpkacSomehow();
const challenge = Certificate.exportChallenge(spkac);
console.log(challenge.toString('utf8'));
// Prints: the challenge as a UTF8 string
```
### Static method: `Certificate.exportPublicKey(spkac[, encoding])`
<!-- YAML
added: v9.0.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The spkac argument can be an ArrayBuffer. Limited the size of
the spkac argument to a maximum of 2**31 - 1 bytes.
-->
* `spkac` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `spkac` string.
* Returns: {Buffer} The public key component of the `spkac` data structure,
which includes a public key and a challenge.
```mjs
const { Certificate } = await import('crypto');
const spkac = getSpkacSomehow();
const publicKey = Certificate.exportPublicKey(spkac);
console.log(publicKey);
// Prints: the public key as <Buffer ...>
```
```cjs
const { Certificate } = require('crypto');
const spkac = getSpkacSomehow();
const publicKey = Certificate.exportPublicKey(spkac);
console.log(publicKey);
// Prints: the public key as <Buffer ...>
```
### Static method: `Certificate.verifySpkac(spkac[, encoding])`
<!-- YAML
added: v9.0.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The spkac argument can be an ArrayBuffer. Added encoding.
Limited the size of the spkac argument to a maximum of
2**31 - 1 bytes.
-->
* `spkac` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `spkac` string.
* Returns: {boolean} `true` if the given `spkac` data structure is valid,
`false` otherwise.
```mjs
import { Buffer } from 'buffer';
const { Certificate } = await import('crypto');
const spkac = getSpkacSomehow();
console.log(Certificate.verifySpkac(Buffer.from(spkac)));
// Prints: true or false
```
```cjs
const { Certificate } = require('crypto');
const { Buffer } = require('buffer');
const spkac = getSpkacSomehow();
console.log(Certificate.verifySpkac(Buffer.from(spkac)));
// Prints: true or false
```
### Legacy API
> Stability: 0 - Deprecated
As a legacy interface, it is possible to create new instances of
the `crypto.Certificate` class as illustrated in the examples below.
#### `new crypto.Certificate()`
Instances of the `Certificate` class can be created using the `new` keyword
or by calling `crypto.Certificate()` as a function:
```mjs
const { Certificate } = await import('crypto');
const cert1 = new Certificate();
const cert2 = Certificate();
```
```cjs
const { Certificate } = require('crypto');
const cert1 = new Certificate();
const cert2 = Certificate();
```
#### `certificate.exportChallenge(spkac[, encoding])`
<!-- YAML
added: v0.11.8
-->
* `spkac` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `spkac` string.
* Returns: {Buffer} The challenge component of the `spkac` data structure, which
includes a public key and a challenge.
```mjs
const { Certificate } = await import('crypto');
const cert = Certificate();
const spkac = getSpkacSomehow();
const challenge = cert.exportChallenge(spkac);
console.log(challenge.toString('utf8'));
// Prints: the challenge as a UTF8 string
```
```cjs
const { Certificate } = require('crypto');
const cert = Certificate();
const spkac = getSpkacSomehow();
const challenge = cert.exportChallenge(spkac);
console.log(challenge.toString('utf8'));
// Prints: the challenge as a UTF8 string
```
#### `certificate.exportPublicKey(spkac[, encoding])`
<!-- YAML
added: v0.11.8
-->
* `spkac` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `spkac` string.
* Returns: {Buffer} The public key component of the `spkac` data structure,
which includes a public key and a challenge.
```mjs
const { Certificate } = await import('crypto');
const cert = Certificate();
const spkac = getSpkacSomehow();
const publicKey = cert.exportPublicKey(spkac);
console.log(publicKey);
// Prints: the public key as <Buffer ...>
```
```cjs
const { Certificate } = require('crypto');
const cert = Certificate();
const spkac = getSpkacSomehow();
const publicKey = cert.exportPublicKey(spkac);
console.log(publicKey);
// Prints: the public key as <Buffer ...>
```
#### `certificate.verifySpkac(spkac[, encoding])`
<!-- YAML
added: v0.11.8
-->
* `spkac` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `spkac` string.
* Returns: {boolean} `true` if the given `spkac` data structure is valid,
`false` otherwise.
```mjs
import { Buffer } from 'buffer';
const { Certificate } = await import('crypto');
const cert = Certificate();
const spkac = getSpkacSomehow();
console.log(cert.verifySpkac(Buffer.from(spkac)));
// Prints: true or false
```
```cjs
const { Certificate } = require('crypto');
const { Buffer } = require('buffer');
const cert = Certificate();
const spkac = getSpkacSomehow();
console.log(cert.verifySpkac(Buffer.from(spkac)));
// Prints: true or false
```
## Class: `Cipher`
<!-- YAML
added: v0.1.94
-->
* Extends: {stream.Transform}
Instances of the `Cipher` class are used to encrypt data. The class can be
used in one of two ways:
* As a [stream][] that is both readable and writable, where plain unencrypted
data is written to produce encrypted data on the readable side, or
* Using the [`cipher.update()`][] and [`cipher.final()`][] methods to produce
the encrypted data.
The [`crypto.createCipher()`][] or [`crypto.createCipheriv()`][] methods are
used to create `Cipher` instances. `Cipher` objects are not to be created
directly using the `new` keyword.
Example: Using `Cipher` objects as streams:
```mjs
const {
scrypt,
randomFill,
createCipheriv
} = await import('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// First, we'll generate the key. The key length is dependent on the algorithm.
// In this case for aes192, it is 24 bytes (192 bits).
scrypt(password, 'salt', 24, (err, key) => {
if (err) throw err;
// Then, we'll generate a random initialization vector
randomFill(new Uint8Array(16), (err, iv) => {
if (err) throw err;
// Once we have the key and iv, we can create and use the cipher...
const cipher = createCipheriv(algorithm, key, iv);
let encrypted = '';
cipher.setEncoding('hex');
cipher.on('data', (chunk) => encrypted += chunk);
cipher.on('end', () => console.log(encrypted));
cipher.write('some clear text data');
cipher.end();
});
});
```
```cjs
const {
scrypt,
randomFill,
createCipheriv
} = require('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// First, we'll generate the key. The key length is dependent on the algorithm.
// In this case for aes192, it is 24 bytes (192 bits).
scrypt(password, 'salt', 24, (err, key) => {
if (err) throw err;
// Then, we'll generate a random initialization vector
randomFill(new Uint8Array(16), (err, iv) => {
if (err) throw err;
// Once we have the key and iv, we can create and use the cipher...
const cipher = createCipheriv(algorithm, key, iv);
let encrypted = '';
cipher.setEncoding('hex');
cipher.on('data', (chunk) => encrypted += chunk);
cipher.on('end', () => console.log(encrypted));
cipher.write('some clear text data');
cipher.end();
});
});
```
Example: Using `Cipher` and piped streams:
```mjs
import {
createReadStream,
createWriteStream,
} from 'fs';
import {
pipeline
} from 'stream';
const {
scrypt,
randomFill,
createCipheriv
} = await import('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// First, we'll generate the key. The key length is dependent on the algorithm.
// In this case for aes192, it is 24 bytes (192 bits).
scrypt(password, 'salt', 24, (err, key) => {
if (err) throw err;
// Then, we'll generate a random initialization vector
randomFill(new Uint8Array(16), (err, iv) => {
if (err) throw err;
const cipher = createCipheriv(algorithm, key, iv);
const input = createReadStream('test.js');
const output = createWriteStream('test.enc');
pipeline(input, cipher, output, (err) => {
if (err) throw err;
});
});
});
```
```cjs
const {
createReadStream,
createWriteStream,
} = require('fs');
const {
pipeline
} = require('stream');
const {
scrypt,
randomFill,
createCipheriv,
} = require('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// First, we'll generate the key. The key length is dependent on the algorithm.
// In this case for aes192, it is 24 bytes (192 bits).
scrypt(password, 'salt', 24, (err, key) => {
if (err) throw err;
// Then, we'll generate a random initialization vector
randomFill(new Uint8Array(16), (err, iv) => {
if (err) throw err;
const cipher = createCipheriv(algorithm, key, iv);
const input = createReadStream('test.js');
const output = createWriteStream('test.enc');
pipeline(input, cipher, output, (err) => {
if (err) throw err;
});
});
});
```
Example: Using the [`cipher.update()`][] and [`cipher.final()`][] methods:
```mjs
const {
scrypt,
randomFill,
createCipheriv
} = await import('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// First, we'll generate the key. The key length is dependent on the algorithm.
// In this case for aes192, it is 24 bytes (192 bits).
scrypt(password, 'salt', 24, (err, key) => {
if (err) throw err;
// Then, we'll generate a random initialization vector
randomFill(new Uint8Array(16), (err, iv) => {
if (err) throw err;
const cipher = createCipheriv(algorithm, key, iv);
let encrypted = cipher.update('some clear text data', 'utf8', 'hex');
encrypted += cipher.final('hex');
console.log(encrypted);
});
});
```
```cjs
const {
scrypt,
randomFill,
createCipheriv,
} = require('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// First, we'll generate the key. The key length is dependent on the algorithm.
// In this case for aes192, it is 24 bytes (192 bits).
scrypt(password, 'salt', 24, (err, key) => {
if (err) throw err;
// Then, we'll generate a random initialization vector
randomFill(new Uint8Array(16), (err, iv) => {
if (err) throw err;
const cipher = createCipheriv(algorithm, key, iv);
let encrypted = cipher.update('some clear text data', 'utf8', 'hex');
encrypted += cipher.final('hex');
console.log(encrypted);
});
});
```
### `cipher.final([outputEncoding])`
<!-- YAML
added: v0.1.94
-->
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string} Any remaining enciphered contents.
If `outputEncoding` is specified, a string is
returned. If an `outputEncoding` is not provided, a [`Buffer`][] is returned.
Once the `cipher.final()` method has been called, the `Cipher` object can no
longer be used to encrypt data. Attempts to call `cipher.final()` more than
once will result in an error being thrown.
### `cipher.getAuthTag()`
<!-- YAML
added: v1.0.0
-->
* Returns: {Buffer} When using an authenticated encryption mode (`GCM`, `CCM`,
and `OCB` are currently supported), the `cipher.getAuthTag()` method returns a
[`Buffer`][] containing the _authentication tag_ that has been computed from
the given data.
The `cipher.getAuthTag()` method should only be called after encryption has
been completed using the [`cipher.final()`][] method.
If the `authTagLength` option was set during the `cipher` instance's creation,
this function will return exactly `authTagLength` bytes.
### `cipher.setAAD(buffer[, options])`
<!-- YAML
added: v1.0.0
-->
* `buffer` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `options` {Object} [`stream.transform` options][]
* `plaintextLength` {number}
* `encoding` {string} The string encoding to use when `buffer` is a string.
* Returns: {Cipher} for method chaining.
When using an authenticated encryption mode (`GCM`, `CCM`, and `OCB` are
currently supported), the `cipher.setAAD()` method sets the value used for the
_additional authenticated data_ (AAD) input parameter.
The `plaintextLength` option is optional for `GCM` and `OCB`. When using `CCM`,
the `plaintextLength` option must be specified and its value must match the
length of the plaintext in bytes. See [CCM mode][].
The `cipher.setAAD()` method must be called before [`cipher.update()`][].
### `cipher.setAutoPadding([autoPadding])`
<!-- YAML
added: v0.7.1
-->
* `autoPadding` {boolean} **Default:** `true`
* Returns: {Cipher} for method chaining.
When using block encryption algorithms, the `Cipher` class will automatically
add padding to the input data to the appropriate block size. To disable the
default padding call `cipher.setAutoPadding(false)`.
When `autoPadding` is `false`, the length of the entire input data must be a
multiple of the cipher's block size or [`cipher.final()`][] will throw an error.
Disabling automatic padding is useful for non-standard padding, for instance
using `0x0` instead of PKCS padding.
The `cipher.setAutoPadding()` method must be called before
[`cipher.final()`][].
### `cipher.update(data[, inputEncoding][, outputEncoding])`
<!-- YAML
added: v0.1.94
changes:
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `data` {string|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the data.
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Updates the cipher with `data`. If the `inputEncoding` argument is given,
the `data`
argument is a string using the specified encoding. If the `inputEncoding`
argument is not given, `data` must be a [`Buffer`][], `TypedArray`, or
`DataView`. If `data` is a [`Buffer`][], `TypedArray`, or `DataView`, then
`inputEncoding` is ignored.
The `outputEncoding` specifies the output format of the enciphered
data. If the `outputEncoding`
is specified, a string using the specified encoding is returned. If no
`outputEncoding` is provided, a [`Buffer`][] is returned.
The `cipher.update()` method can be called multiple times with new data until
[`cipher.final()`][] is called. Calling `cipher.update()` after
[`cipher.final()`][] will result in an error being thrown.
## Class: `Decipher`
<!-- YAML
added: v0.1.94
-->
* Extends: {stream.Transform}
Instances of the `Decipher` class are used to decrypt data. The class can be
used in one of two ways:
* As a [stream][] that is both readable and writable, where plain encrypted
data is written to produce unencrypted data on the readable side, or
* Using the [`decipher.update()`][] and [`decipher.final()`][] methods to
produce the unencrypted data.
The [`crypto.createDecipher()`][] or [`crypto.createDecipheriv()`][] methods are
used to create `Decipher` instances. `Decipher` objects are not to be created
directly using the `new` keyword.
Example: Using `Decipher` objects as streams:
```mjs
import { Buffer } from 'buffer';
const {
scryptSync,
createDecipheriv
} = await import('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// Key length is dependent on the algorithm. In this case for aes192, it is
// 24 bytes (192 bits).
// Use the async `crypto.scrypt()` instead.
const key = scryptSync(password, 'salt', 24);
// The IV is usually passed along with the ciphertext.
const iv = Buffer.alloc(16, 0); // Initialization vector.
const decipher = createDecipheriv(algorithm, key, iv);
let decrypted = '';
decipher.on('readable', () => {
while (null !== (chunk = decipher.read())) {
decrypted += chunk.toString('utf8');
}
});
decipher.on('end', () => {
console.log(decrypted);
// Prints: some clear text data
});
// Encrypted with same algorithm, key and iv.
const encrypted =
'e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa';
decipher.write(encrypted, 'hex');
decipher.end();
```
```cjs
const {
scryptSync,
createDecipheriv,
} = require('crypto');
const { Buffer } = require('buffer');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// Key length is dependent on the algorithm. In this case for aes192, it is
// 24 bytes (192 bits).
// Use the async `crypto.scrypt()` instead.
const key = scryptSync(password, 'salt', 24);
// The IV is usually passed along with the ciphertext.
const iv = Buffer.alloc(16, 0); // Initialization vector.
const decipher = createDecipheriv(algorithm, key, iv);
let decrypted = '';
decipher.on('readable', () => {
while (null !== (chunk = decipher.read())) {
decrypted += chunk.toString('utf8');
}
});
decipher.on('end', () => {
console.log(decrypted);
// Prints: some clear text data
});
// Encrypted with same algorithm, key and iv.
const encrypted =
'e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa';
decipher.write(encrypted, 'hex');
decipher.end();
```
Example: Using `Decipher` and piped streams:
```mjs
import {
createReadStream,
createWriteStream,
} from 'fs';
import { Buffer } from 'buffer';
const {
scryptSync,
createDecipheriv
} = await import('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// Use the async `crypto.scrypt()` instead.
const key = scryptSync(password, 'salt', 24);
// The IV is usually passed along with the ciphertext.
const iv = Buffer.alloc(16, 0); // Initialization vector.
const decipher = createDecipheriv(algorithm, key, iv);
const input = createReadStream('test.enc');
const output = createWriteStream('test.js');
input.pipe(decipher).pipe(output);
```
```cjs
const {
createReadStream,
createWriteStream,
} = require('fs');
const {
scryptSync,
createDecipheriv,
} = require('crypto');
const { Buffer } = require('buffer');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// Use the async `crypto.scrypt()` instead.
const key = scryptSync(password, 'salt', 24);
// The IV is usually passed along with the ciphertext.
const iv = Buffer.alloc(16, 0); // Initialization vector.
const decipher = createDecipheriv(algorithm, key, iv);
const input = createReadStream('test.enc');
const output = createWriteStream('test.js');
input.pipe(decipher).pipe(output);
```
Example: Using the [`decipher.update()`][] and [`decipher.final()`][] methods:
```mjs
import { Buffer } from 'buffer';
const {
scryptSync,
createDecipheriv
} = await import('crypto');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// Use the async `crypto.scrypt()` instead.
const key = scryptSync(password, 'salt', 24);
// The IV is usually passed along with the ciphertext.
const iv = Buffer.alloc(16, 0); // Initialization vector.
const decipher = createDecipheriv(algorithm, key, iv);
// Encrypted using same algorithm, key and iv.
const encrypted =
'e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa';
let decrypted = decipher.update(encrypted, 'hex', 'utf8');
decrypted += decipher.final('utf8');
console.log(decrypted);
// Prints: some clear text data
```
```cjs
const {
scryptSync,
createDecipheriv,
} = require('crypto');
const { Buffer } = require('buffer');
const algorithm = 'aes-192-cbc';
const password = 'Password used to generate key';
// Use the async `crypto.scrypt()` instead.
const key = scryptSync(password, 'salt', 24);
// The IV is usually passed along with the ciphertext.
const iv = Buffer.alloc(16, 0); // Initialization vector.
const decipher = createDecipheriv(algorithm, key, iv);
// Encrypted using same algorithm, key and iv.
const encrypted =
'e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa';
let decrypted = decipher.update(encrypted, 'hex', 'utf8');
decrypted += decipher.final('utf8');
console.log(decrypted);
// Prints: some clear text data
```
### `decipher.final([outputEncoding])`
<!-- YAML
added: v0.1.94
-->
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string} Any remaining deciphered contents.
If `outputEncoding` is specified, a string is
returned. If an `outputEncoding` is not provided, a [`Buffer`][] is returned.
Once the `decipher.final()` method has been called, the `Decipher` object can
no longer be used to decrypt data. Attempts to call `decipher.final()` more
than once will result in an error being thrown.
### `decipher.setAAD(buffer[, options])`
<!-- YAML
added: v1.0.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The buffer argument can be a string or ArrayBuffer and is
limited to no more than 2 ** 31 - 1 bytes.
- version: v7.2.0
pr-url: https://github.com/nodejs/node/pull/9398
description: This method now returns a reference to `decipher`.
-->
* `buffer` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `options` {Object} [`stream.transform` options][]
* `plaintextLength` {number}
* `encoding` {string} String encoding to use when `buffer` is a string.
* Returns: {Decipher} for method chaining.
When using an authenticated encryption mode (`GCM`, `CCM`, and `OCB` are
currently supported), the `decipher.setAAD()` method sets the value used for the
_additional authenticated data_ (AAD) input parameter.
The `options` argument is optional for `GCM`. When using `CCM`, the
`plaintextLength` option must be specified and its value must match the length
of the ciphertext in bytes. See [CCM mode][].
The `decipher.setAAD()` method must be called before [`decipher.update()`][].
When passing a string as the `buffer`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
### `decipher.setAuthTag(buffer[, encoding])`
<!-- YAML
added: v1.0.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The buffer argument can be a string or ArrayBuffer and is
limited to no more than 2 ** 31 - 1 bytes.
- version: v11.0.0
pr-url: https://github.com/nodejs/node/pull/17825
description: This method now throws if the GCM tag length is invalid.
- version: v7.2.0
pr-url: https://github.com/nodejs/node/pull/9398
description: This method now returns a reference to `decipher`.
-->
* `buffer` {string|Buffer|ArrayBuffer|TypedArray|DataView}
* `encoding` {string} String encoding to use when `buffer` is a string.
* Returns: {Decipher} for method chaining.
When using an authenticated encryption mode (`GCM`, `CCM`, and `OCB` are
currently supported), the `decipher.setAuthTag()` method is used to pass in the
received _authentication tag_. If no tag is provided, or if the cipher text
has been tampered with, [`decipher.final()`][] will throw, indicating that the
cipher text should be discarded due to failed authentication. If the tag length
is invalid according to [NIST SP 800-38D][] or does not match the value of the
`authTagLength` option, `decipher.setAuthTag()` will throw an error.
The `decipher.setAuthTag()` method must be called before [`decipher.update()`][]
for `CCM` mode or before [`decipher.final()`][] for `GCM` and `OCB` modes.
`decipher.setAuthTag()` can only be called once.
When passing a string as the authentication tag, please consider
[caveats when using strings as inputs to cryptographic APIs][].
### `decipher.setAutoPadding([autoPadding])`
<!-- YAML
added: v0.7.1
-->
* `autoPadding` {boolean} **Default:** `true`
* Returns: {Decipher} for method chaining.
When data has been encrypted without standard block padding, calling
`decipher.setAutoPadding(false)` will disable automatic padding to prevent
[`decipher.final()`][] from checking for and removing padding.
Turning auto padding off will only work if the input data's length is a
multiple of the ciphers block size.
The `decipher.setAutoPadding()` method must be called before
[`decipher.final()`][].
### `decipher.update(data[, inputEncoding][, outputEncoding])`
<!-- YAML
added: v0.1.94
changes:
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `data` {string|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the `data` string.
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Updates the decipher with `data`. If the `inputEncoding` argument is given,
the `data`
argument is a string using the specified encoding. If the `inputEncoding`
argument is not given, `data` must be a [`Buffer`][]. If `data` is a
[`Buffer`][] then `inputEncoding` is ignored.
The `outputEncoding` specifies the output format of the enciphered
data. If the `outputEncoding`
is specified, a string using the specified encoding is returned. If no
`outputEncoding` is provided, a [`Buffer`][] is returned.
The `decipher.update()` method can be called multiple times with new data until
[`decipher.final()`][] is called. Calling `decipher.update()` after
[`decipher.final()`][] will result in an error being thrown.
## Class: `DiffieHellman`
<!-- YAML
added: v0.5.0
-->
The `DiffieHellman` class is a utility for creating Diffie-Hellman key
exchanges.
Instances of the `DiffieHellman` class can be created using the
[`crypto.createDiffieHellman()`][] function.
```mjs
import assert from 'assert';
const {
createDiffieHellman
} = await import('crypto');
// Generate Alice's keys...
const alice = createDiffieHellman(2048);
const aliceKey = alice.generateKeys();
// Generate Bob's keys...
const bob = createDiffieHellman(alice.getPrime(), alice.getGenerator());
const bobKey = bob.generateKeys();
// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);
// OK
assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));
```
```cjs
const assert = require('assert');
const {
createDiffieHellman,
} = require('crypto');
// Generate Alice's keys...
const alice = createDiffieHellman(2048);
const aliceKey = alice.generateKeys();
// Generate Bob's keys...
const bob = createDiffieHellman(alice.getPrime(), alice.getGenerator());
const bobKey = bob.generateKeys();
// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);
// OK
assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));
```
### `diffieHellman.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])`
<!-- YAML
added: v0.5.0
-->
* `otherPublicKey` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of an `otherPublicKey` string.
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Computes the shared secret using `otherPublicKey` as the other
party's public key and returns the computed shared secret. The supplied
key is interpreted using the specified `inputEncoding`, and secret is
encoded using specified `outputEncoding`.
If the `inputEncoding` is not
provided, `otherPublicKey` is expected to be a [`Buffer`][],
`TypedArray`, or `DataView`.
If `outputEncoding` is given a string is returned; otherwise, a
[`Buffer`][] is returned.
### `diffieHellman.generateKeys([encoding])`
<!-- YAML
added: v0.5.0
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Generates private and public Diffie-Hellman key values, and returns
the public key in the specified `encoding`. This key should be
transferred to the other party.
If `encoding` is provided a string is returned; otherwise a
[`Buffer`][] is returned.
### `diffieHellman.getGenerator([encoding])`
<!-- YAML
added: v0.5.0
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Returns the Diffie-Hellman generator in the specified `encoding`.
If `encoding` is provided a string is
returned; otherwise a [`Buffer`][] is returned.
### `diffieHellman.getPrime([encoding])`
<!-- YAML
added: v0.5.0
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Returns the Diffie-Hellman prime in the specified `encoding`.
If `encoding` is provided a string is
returned; otherwise a [`Buffer`][] is returned.
### `diffieHellman.getPrivateKey([encoding])`
<!-- YAML
added: v0.5.0
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Returns the Diffie-Hellman private key in the specified `encoding`.
If `encoding` is provided a
string is returned; otherwise a [`Buffer`][] is returned.
### `diffieHellman.getPublicKey([encoding])`
<!-- YAML
added: v0.5.0
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Returns the Diffie-Hellman public key in the specified `encoding`.
If `encoding` is provided a
string is returned; otherwise a [`Buffer`][] is returned.
### `diffieHellman.setPrivateKey(privateKey[, encoding])`
<!-- YAML
added: v0.5.0
-->
* `privateKey` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `privateKey` string.
Sets the Diffie-Hellman private key. If the `encoding` argument is provided,
`privateKey` is expected
to be a string. If no `encoding` is provided, `privateKey` is expected
to be a [`Buffer`][], `TypedArray`, or `DataView`.
### `diffieHellman.setPublicKey(publicKey[, encoding])`
<!-- YAML
added: v0.5.0
-->
* `publicKey` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `publicKey` string.
Sets the Diffie-Hellman public key. If the `encoding` argument is provided,
`publicKey` is expected
to be a string. If no `encoding` is provided, `publicKey` is expected
to be a [`Buffer`][], `TypedArray`, or `DataView`.
### `diffieHellman.verifyError`
<!-- YAML
added: v0.11.12
-->
A bit field containing any warnings and/or errors resulting from a check
performed during initialization of the `DiffieHellman` object.
The following values are valid for this property (as defined in `constants`
module):
* `DH_CHECK_P_NOT_SAFE_PRIME`
* `DH_CHECK_P_NOT_PRIME`
* `DH_UNABLE_TO_CHECK_GENERATOR`
* `DH_NOT_SUITABLE_GENERATOR`
## Class: `DiffieHellmanGroup`
<!-- YAML
added: v0.7.5
-->
The `DiffieHellmanGroup` class takes a well-known modp group as its argument.
It works the same as `DiffieHellman`, except that it does not allow changing
its keys after creation. In other words, it does not implement `setPublicKey()`
or `setPrivateKey()` methods.
```mjs
const { createDiffieHellmanGroup } = await import('crypto');
const dh = createDiffieHellmanGroup('modp1');
```
```cjs
const { createDiffieHellmanGroup } = require('crypto');
const dh = createDiffieHellmanGroup('modp1');
```
The name (e.g. `'modp1'`) is taken from [RFC 2412][] (modp1 and 2) and
[RFC 3526][]:
```console
$ perl -ne 'print "$1\n" if /"(modp\d+)"/' src/node_crypto_groups.h
modp1 # 768 bits
modp2 # 1024 bits
modp5 # 1536 bits
modp14 # 2048 bits
modp15 # etc.
modp16
modp17
modp18
```
## Class: `ECDH`
<!-- YAML
added: v0.11.14
-->
The `ECDH` class is a utility for creating Elliptic Curve Diffie-Hellman (ECDH)
key exchanges.
Instances of the `ECDH` class can be created using the
[`crypto.createECDH()`][] function.
```mjs
import assert from 'assert';
const {
createECDH
} = await import('crypto');
// Generate Alice's keys...
const alice = createECDH('secp521r1');
const aliceKey = alice.generateKeys();
// Generate Bob's keys...
const bob = createECDH('secp521r1');
const bobKey = bob.generateKeys();
// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);
assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));
// OK
```
```cjs
const assert = require('assert');
const {
createECDH,
} = require('crypto');
// Generate Alice's keys...
const alice = createECDH('secp521r1');
const aliceKey = alice.generateKeys();
// Generate Bob's keys...
const bob = createECDH('secp521r1');
const bobKey = bob.generateKeys();
// Exchange and generate the secret...
const aliceSecret = alice.computeSecret(bobKey);
const bobSecret = bob.computeSecret(aliceKey);
assert.strictEqual(aliceSecret.toString('hex'), bobSecret.toString('hex'));
// OK
```
### Static method: `ECDH.convertKey(key, curve[, inputEncoding[, outputEncoding[, format]]])`
<!-- YAML
added: v10.0.0
-->
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `curve` {string}
* `inputEncoding` {string} The [encoding][] of the `key` string.
* `outputEncoding` {string} The [encoding][] of the return value.
* `format` {string} **Default:** `'uncompressed'`
* Returns: {Buffer | string}
Converts the EC Diffie-Hellman public key specified by `key` and `curve` to the
format specified by `format`. The `format` argument specifies point encoding
and can be `'compressed'`, `'uncompressed'` or `'hybrid'`. The supplied key is
interpreted using the specified `inputEncoding`, and the returned key is encoded
using the specified `outputEncoding`.
Use [`crypto.getCurves()`][] to obtain a list of available curve names.
On recent OpenSSL releases, `openssl ecparam -list_curves` will also display
the name and description of each available elliptic curve.
If `format` is not specified the point will be returned in `'uncompressed'`
format.
If the `inputEncoding` is not provided, `key` is expected to be a [`Buffer`][],
`TypedArray`, or `DataView`.
Example (uncompressing a key):
```mjs
const {
createECDH,
ECDH
} = await import('crypto');
const ecdh = createECDH('secp256k1');
ecdh.generateKeys();
const compressedKey = ecdh.getPublicKey('hex', 'compressed');
const uncompressedKey = ECDH.convertKey(compressedKey,
'secp256k1',
'hex',
'hex',
'uncompressed');
// The converted key and the uncompressed public key should be the same
console.log(uncompressedKey === ecdh.getPublicKey('hex'));
```
```cjs
const {
createECDH,
ECDH,
} = require('crypto');
const ecdh = createECDH('secp256k1');
ecdh.generateKeys();
const compressedKey = ecdh.getPublicKey('hex', 'compressed');
const uncompressedKey = ECDH.convertKey(compressedKey,
'secp256k1',
'hex',
'hex',
'uncompressed');
// The converted key and the uncompressed public key should be the same
console.log(uncompressedKey === ecdh.getPublicKey('hex'));
```
### `ecdh.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])`
<!-- YAML
added: v0.11.14
changes:
- version: v10.0.0
pr-url: https://github.com/nodejs/node/pull/16849
description: Changed error format to better support invalid public key
error.
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `otherPublicKey` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the `otherPublicKey` string.
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Computes the shared secret using `otherPublicKey` as the other
party's public key and returns the computed shared secret. The supplied
key is interpreted using specified `inputEncoding`, and the returned secret
is encoded using the specified `outputEncoding`.
If the `inputEncoding` is not
provided, `otherPublicKey` is expected to be a [`Buffer`][], `TypedArray`, or
`DataView`.
If `outputEncoding` is given a string will be returned; otherwise a
[`Buffer`][] is returned.
`ecdh.computeSecret` will throw an
`ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY` error when `otherPublicKey`
lies outside of the elliptic curve. Since `otherPublicKey` is
usually supplied from a remote user over an insecure network,
be sure to handle this exception accordingly.
### `ecdh.generateKeys([encoding[, format]])`
<!-- YAML
added: v0.11.14
-->
* `encoding` {string} The [encoding][] of the return value.
* `format` {string} **Default:** `'uncompressed'`
* Returns: {Buffer | string}
Generates private and public EC Diffie-Hellman key values, and returns
the public key in the specified `format` and `encoding`. This key should be
transferred to the other party.
The `format` argument specifies point encoding and can be `'compressed'` or
`'uncompressed'`. If `format` is not specified, the point will be returned in
`'uncompressed'` format.
If `encoding` is provided a string is returned; otherwise a [`Buffer`][]
is returned.
### `ecdh.getPrivateKey([encoding])`
<!-- YAML
added: v0.11.14
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string} The EC Diffie-Hellman in the specified `encoding`.
If `encoding` is specified, a string is returned; otherwise a [`Buffer`][] is
returned.
### `ecdh.getPublicKey([encoding][, format])`
<!-- YAML
added: v0.11.14
-->
* `encoding` {string} The [encoding][] of the return value.
* `format` {string} **Default:** `'uncompressed'`
* Returns: {Buffer | string} The EC Diffie-Hellman public key in the specified
`encoding` and `format`.
The `format` argument specifies point encoding and can be `'compressed'` or
`'uncompressed'`. If `format` is not specified the point will be returned in
`'uncompressed'` format.
If `encoding` is specified, a string is returned; otherwise a [`Buffer`][] is
returned.
### `ecdh.setPrivateKey(privateKey[, encoding])`
<!-- YAML
added: v0.11.14
-->
* `privateKey` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `privateKey` string.
Sets the EC Diffie-Hellman private key.
If `encoding` is provided, `privateKey` is expected
to be a string; otherwise `privateKey` is expected to be a [`Buffer`][],
`TypedArray`, or `DataView`.
If `privateKey` is not valid for the curve specified when the `ECDH` object was
created, an error is thrown. Upon setting the private key, the associated
public point (key) is also generated and set in the `ECDH` object.
### `ecdh.setPublicKey(publicKey[, encoding])`
<!-- YAML
added: v0.11.14
deprecated: v5.2.0
-->
> Stability: 0 - Deprecated
* `publicKey` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The [encoding][] of the `publicKey` string.
Sets the EC Diffie-Hellman public key.
If `encoding` is provided `publicKey` is expected to
be a string; otherwise a [`Buffer`][], `TypedArray`, or `DataView` is expected.
There is not normally a reason to call this method because `ECDH`
only requires a private key and the other party's public key to compute the
shared secret. Typically either [`ecdh.generateKeys()`][] or
[`ecdh.setPrivateKey()`][] will be called. The [`ecdh.setPrivateKey()`][] method
attempts to generate the public point/key associated with the private key being
set.
Example (obtaining a shared secret):
```mjs
const {
createECDH,
createHash
} = await import('crypto');
const alice = createECDH('secp256k1');
const bob = createECDH('secp256k1');
// This is a shortcut way of specifying one of Alice's previous private
// keys. It would be unwise to use such a predictable private key in a real
// application.
alice.setPrivateKey(
createHash('sha256').update('alice', 'utf8').digest()
);
// Bob uses a newly generated cryptographically strong
// pseudorandom key pair
bob.generateKeys();
const aliceSecret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
const bobSecret = bob.computeSecret(alice.getPublicKey(), null, 'hex');
// aliceSecret and bobSecret should be the same shared secret value
console.log(aliceSecret === bobSecret);
```
```cjs
const {
createECDH,
createHash,
} = require('crypto');
const alice = createECDH('secp256k1');
const bob = createECDH('secp256k1');
// This is a shortcut way of specifying one of Alice's previous private
// keys. It would be unwise to use such a predictable private key in a real
// application.
alice.setPrivateKey(
createHash('sha256').update('alice', 'utf8').digest()
);
// Bob uses a newly generated cryptographically strong
// pseudorandom key pair
bob.generateKeys();
const aliceSecret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
const bobSecret = bob.computeSecret(alice.getPublicKey(), null, 'hex');
// aliceSecret and bobSecret should be the same shared secret value
console.log(aliceSecret === bobSecret);
```
## Class: `Hash`
<!-- YAML
added: v0.1.92
-->
* Extends: {stream.Transform}
The `Hash` class is a utility for creating hash digests of data. It can be
used in one of two ways:
* As a [stream][] that is both readable and writable, where data is written
to produce a computed hash digest on the readable side, or
* Using the [`hash.update()`][] and [`hash.digest()`][] methods to produce the
computed hash.
The [`crypto.createHash()`][] method is used to create `Hash` instances. `Hash`
objects are not to be created directly using the `new` keyword.
Example: Using `Hash` objects as streams:
```mjs
const {
createHash
} = await import('crypto');
const hash = createHash('sha256');
hash.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = hash.read();
if (data) {
console.log(data.toString('hex'));
// Prints:
// 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
}
});
hash.write('some data to hash');
hash.end();
```
```cjs
const {
createHash,
} = require('crypto');
const hash = createHash('sha256');
hash.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = hash.read();
if (data) {
console.log(data.toString('hex'));
// Prints:
// 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
}
});
hash.write('some data to hash');
hash.end();
```
Example: Using `Hash` and piped streams:
```mjs
import { createReadStream } from 'fs';
import { stdout } from 'process';
const { createHash } = await import('crypto');
const hash = createHash('sha256');
const input = createReadStream('test.js');
input.pipe(hash).setEncoding('hex').pipe(stdout);
```
```cjs
const { createReadStream } = require('fs');
const { createHash } = require('crypto');
const { stdout } = require('process');
const hash = createHash('sha256');
const input = createReadStream('test.js');
input.pipe(hash).setEncoding('hex').pipe(stdout);
```
Example: Using the [`hash.update()`][] and [`hash.digest()`][] methods:
```mjs
const {
createHash
} = await import('crypto');
const hash = createHash('sha256');
hash.update('some data to hash');
console.log(hash.digest('hex'));
// Prints:
// 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
```
```cjs
const {
createHash,
} = require('crypto');
const hash = createHash('sha256');
hash.update('some data to hash');
console.log(hash.digest('hex'));
// Prints:
// 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
```
### `hash.copy([options])`
<!-- YAML
added: v13.1.0
-->
* `options` {Object} [`stream.transform` options][]
* Returns: {Hash}
Creates a new `Hash` object that contains a deep copy of the internal state
of the current `Hash` object.
The optional `options` argument controls stream behavior. For XOF hash
functions such as `'shake256'`, the `outputLength` option can be used to
specify the desired output length in bytes.
An error is thrown when an attempt is made to copy the `Hash` object after
its [`hash.digest()`][] method has been called.
```mjs
// Calculate a rolling hash.
const {
createHash
} = await import('crypto');
const hash = createHash('sha256');
hash.update('one');
console.log(hash.copy().digest('hex'));
hash.update('two');
console.log(hash.copy().digest('hex'));
hash.update('three');
console.log(hash.copy().digest('hex'));
// Etc.
```
```cjs
// Calculate a rolling hash.
const {
createHash,
} = require('crypto');
const hash = createHash('sha256');
hash.update('one');
console.log(hash.copy().digest('hex'));
hash.update('two');
console.log(hash.copy().digest('hex'));
hash.update('three');
console.log(hash.copy().digest('hex'));
// Etc.
```
### `hash.digest([encoding])`
<!-- YAML
added: v0.1.92
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Calculates the digest of all of the data passed to be hashed (using the
[`hash.update()`][] method).
If `encoding` is provided a string will be returned; otherwise
a [`Buffer`][] is returned.
The `Hash` object can not be used again after `hash.digest()` method has been
called. Multiple calls will cause an error to be thrown.
### `hash.update(data[, inputEncoding])`
<!-- YAML
added: v0.1.92
changes:
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `data` {string|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the `data` string.
Updates the hash content with the given `data`, the encoding of which
is given in `inputEncoding`.
If `encoding` is not provided, and the `data` is a string, an
encoding of `'utf8'` is enforced. If `data` is a [`Buffer`][], `TypedArray`, or
`DataView`, then `inputEncoding` is ignored.
This can be called many times with new data as it is streamed.
## Class: `Hmac`
<!-- YAML
added: v0.1.94
-->
* Extends: {stream.Transform}
The `Hmac` class is a utility for creating cryptographic HMAC digests. It can
be used in one of two ways:
* As a [stream][] that is both readable and writable, where data is written
to produce a computed HMAC digest on the readable side, or
* Using the [`hmac.update()`][] and [`hmac.digest()`][] methods to produce the
computed HMAC digest.
The [`crypto.createHmac()`][] method is used to create `Hmac` instances. `Hmac`
objects are not to be created directly using the `new` keyword.
Example: Using `Hmac` objects as streams:
```mjs
const {
createHmac
} = await import('crypto');
const hmac = createHmac('sha256', 'a secret');
hmac.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = hmac.read();
if (data) {
console.log(data.toString('hex'));
// Prints:
// 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e
}
});
hmac.write('some data to hash');
hmac.end();
```
```cjs
const {
createHmac,
} = require('crypto');
const hmac = createHmac('sha256', 'a secret');
hmac.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = hmac.read();
if (data) {
console.log(data.toString('hex'));
// Prints:
// 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e
}
});
hmac.write('some data to hash');
hmac.end();
```
Example: Using `Hmac` and piped streams:
```mjs
import { createReadStream } from 'fs';
import { stdout } from 'process';
const {
createHmac
} = await import('crypto');
const hmac = createHmac('sha256', 'a secret');
const input = createReadStream('test.js');
input.pipe(hmac).pipe(stdout);
```
```cjs
const {
createReadStream,
} = require('fs');
const {
createHmac,
} = require('crypto');
const { stdout } = require('process');
const hmac = createHmac('sha256', 'a secret');
const input = createReadStream('test.js');
input.pipe(hmac).pipe(stdout);
```
Example: Using the [`hmac.update()`][] and [`hmac.digest()`][] methods:
```mjs
const {
createHmac
} = await import('crypto');
const hmac = createHmac('sha256', 'a secret');
hmac.update('some data to hash');
console.log(hmac.digest('hex'));
// Prints:
// 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e
```
```cjs
const {
createHmac,
} = require('crypto');
const hmac = createHmac('sha256', 'a secret');
hmac.update('some data to hash');
console.log(hmac.digest('hex'));
// Prints:
// 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e
```
### `hmac.digest([encoding])`
<!-- YAML
added: v0.1.94
-->
* `encoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
Calculates the HMAC digest of all of the data passed using [`hmac.update()`][].
If `encoding` is
provided a string is returned; otherwise a [`Buffer`][] is returned;
The `Hmac` object can not be used again after `hmac.digest()` has been
called. Multiple calls to `hmac.digest()` will result in an error being thrown.
### `hmac.update(data[, inputEncoding])`
<!-- YAML
added: v0.1.94
changes:
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `data` {string|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the `data` string.
Updates the `Hmac` content with the given `data`, the encoding of which
is given in `inputEncoding`.
If `encoding` is not provided, and the `data` is a string, an
encoding of `'utf8'` is enforced. If `data` is a [`Buffer`][], `TypedArray`, or
`DataView`, then `inputEncoding` is ignored.
This can be called many times with new data as it is streamed.
## Class: `KeyObject`
<!-- YAML
added: v11.6.0
changes:
- version:
- v14.5.0
- v12.19.0
pr-url: https://github.com/nodejs/node/pull/33360
description: Instances of this class can now be passed to worker threads
using `postMessage`.
- version: v11.13.0
pr-url: https://github.com/nodejs/node/pull/26438
description: This class is now exported.
-->
Node.js uses a `KeyObject` class to represent a symmetric or asymmetric key,
and each kind of key exposes different functions. The
[`crypto.createSecretKey()`][], [`crypto.createPublicKey()`][] and
[`crypto.createPrivateKey()`][] methods are used to create `KeyObject`
instances. `KeyObject` objects are not to be created directly using the `new`
keyword.
Most applications should consider using the new `KeyObject` API instead of
passing keys as strings or `Buffer`s due to improved security features.
`KeyObject` instances can be passed to other threads via [`postMessage()`][].
The receiver obtains a cloned `KeyObject`, and the `KeyObject` does not need to
be listed in the `transferList` argument.
### Static method: `KeyObject.from(key)`
<!-- YAML
added: v15.0.0
-->
* `key` {CryptoKey}
* Returns: {KeyObject}
Example: Converting a `CryptoKey` instance to a `KeyObject`:
```mjs
const { webcrypto, KeyObject } = await import('crypto');
const { subtle } = webcrypto;
const key = await subtle.generateKey({
name: 'HMAC',
hash: 'SHA-256',
length: 256
}, true, ['sign', 'verify']);
const keyObject = KeyObject.from(key);
console.log(keyObject.symmetricKeySize);
// Prints: 32 (symmetric key size in bytes)
```
```cjs
const {
webcrypto: {
subtle,
},
KeyObject,
} = require('crypto');
(async function() {
const key = await subtle.generateKey({
name: 'HMAC',
hash: 'SHA-256',
length: 256
}, true, ['sign', 'verify']);
const keyObject = KeyObject.from(key);
console.log(keyObject.symmetricKeySize);
// Prints: 32 (symmetric key size in bytes)
})();
```
### `keyObject.asymmetricKeyDetails`
<!-- YAML
added: v15.7.0
changes:
- version: v16.9.0
pr-url: https://github.com/nodejs/node/pull/39851
description: Expose `RSASSA-PSS-params` sequence parameters
for RSA-PSS keys.
-->
* {Object}
* `modulusLength`: {number} Key size in bits (RSA, DSA).
* `publicExponent`: {bigint} Public exponent (RSA).
* `hashAlgorithm`: {string} Name of the message digest (RSA-PSS).
* `mgf1HashAlgorithm`: {string} Name of the message digest used by
MGF1 (RSA-PSS).
* `saltLength`: {number} Minimal salt length in bytes (RSA-PSS).
* `divisorLength`: {number} Size of `q` in bits (DSA).
* `namedCurve`: {string} Name of the curve (EC).
This property exists only on asymmetric keys. Depending on the type of the key,
this object contains information about the key. None of the information obtained
through this property can be used to uniquely identify a key or to compromise
the security of the key.
For RSA-PSS keys, if the key material contains a `RSASSA-PSS-params` sequence,
the `hashAlgorithm`, `mgf1HashAlgorithm`, and `saltLength` properties will be
set.
Other key details might be exposed via this API using additional attributes.
### `keyObject.asymmetricKeyType`
<!-- YAML
added: v11.6.0
changes:
- version:
- v13.9.0
- v12.17.0
pr-url: https://github.com/nodejs/node/pull/31178
description: Added support for `'dh'`.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26960
description: Added support for `'rsa-pss'`.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26786
description: This property now returns `undefined` for KeyObject
instances of unrecognized type instead of aborting.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26774
description: Added support for `'x25519'` and `'x448'`.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26319
description: Added support for `'ed25519'` and `'ed448'`.
-->
* {string}
For asymmetric keys, this property represents the type of the key. Supported key
types are:
* `'rsa'` (OID 1.2.840.113549.1.1.1)
* `'rsa-pss'` (OID 1.2.840.113549.1.1.10)
* `'dsa'` (OID 1.2.840.10040.4.1)
* `'ec'` (OID 1.2.840.10045.2.1)
* `'x25519'` (OID 1.3.101.110)
* `'x448'` (OID 1.3.101.111)
* `'ed25519'` (OID 1.3.101.112)
* `'ed448'` (OID 1.3.101.113)
* `'dh'` (OID 1.2.840.113549.1.3.1)
This property is `undefined` for unrecognized `KeyObject` types and symmetric
keys.
### `keyObject.export([options])`
<!-- YAML
added: v11.6.0
changes:
- version: v15.9.0
pr-url: https://github.com/nodejs/node/pull/37081
description: Added support for `'jwk'` format.
-->
* `options`: {Object}
* Returns: {string | Buffer | Object}
For symmetric keys, the following encoding options can be used:
* `format`: {string} Must be `'buffer'` (default) or `'jwk'`.
For public keys, the following encoding options can be used:
* `type`: {string} Must be one of `'pkcs1'` (RSA only) or `'spki'`.
* `format`: {string} Must be `'pem'`, `'der'`, or `'jwk'`.
For private keys, the following encoding options can be used:
* `type`: {string} Must be one of `'pkcs1'` (RSA only), `'pkcs8'` or
`'sec1'` (EC only).
* `format`: {string} Must be `'pem'`, `'der'`, or `'jwk'`.
* `cipher`: {string} If specified, the private key will be encrypted with
the given `cipher` and `passphrase` using PKCS#5 v2.0 password based
encryption.
* `passphrase`: {string | Buffer} The passphrase to use for encryption, see
`cipher`.
The result type depends on the selected encoding format, when PEM the
result is a string, when DER it will be a buffer containing the data
encoded as DER, when [JWK][] it will be an object.
When [JWK][] encoding format was selected, all other encoding options are
ignored.
PKCS#1, SEC1, and PKCS#8 type keys can be encrypted by using a combination of
the `cipher` and `format` options. The PKCS#8 `type` can be used with any
`format` to encrypt any key algorithm (RSA, EC, or DH) by specifying a
`cipher`. PKCS#1 and SEC1 can only be encrypted by specifying a `cipher`
when the PEM `format` is used. For maximum compatibility, use PKCS#8 for
encrypted private keys. Since PKCS#8 defines its own
encryption mechanism, PEM-level encryption is not supported when encrypting
a PKCS#8 key. See [RFC 5208][] for PKCS#8 encryption and [RFC 1421][] for
PKCS#1 and SEC1 encryption.
### `keyObject.symmetricKeySize`
<!-- YAML
added: v11.6.0
-->
* {number}
For secret keys, this property represents the size of the key in bytes. This
property is `undefined` for asymmetric keys.
### `keyObject.type`
<!-- YAML
added: v11.6.0
-->
* {string}
Depending on the type of this `KeyObject`, this property is either
`'secret'` for secret (symmetric) keys, `'public'` for public (asymmetric) keys
or `'private'` for private (asymmetric) keys.
## Class: `Sign`
<!-- YAML
added: v0.1.92
-->
* Extends: {stream.Writable}
The `Sign` class is a utility for generating signatures. It can be used in one
of two ways:
* As a writable [stream][], where data to be signed is written and the
[`sign.sign()`][] method is used to generate and return the signature, or
* Using the [`sign.update()`][] and [`sign.sign()`][] methods to produce the
signature.
The [`crypto.createSign()`][] method is used to create `Sign` instances. The
argument is the string name of the hash function to use. `Sign` objects are not
to be created directly using the `new` keyword.
Example: Using `Sign` and [`Verify`][] objects as streams:
```mjs
const {
generateKeyPairSync,
createSign,
createVerify
} = await import('crypto');
const { privateKey, publicKey } = generateKeyPairSync('ec', {
namedCurve: 'sect239k1'
});
const sign = createSign('SHA256');
sign.write('some data to sign');
sign.end();
const signature = sign.sign(privateKey, 'hex');
const verify = createVerify('SHA256');
verify.write('some data to sign');
verify.end();
console.log(verify.verify(publicKey, signature, 'hex'));
// Prints: true
```
```cjs
const {
generateKeyPairSync,
createSign,
createVerify,
} = require('crypto');
const { privateKey, publicKey } = generateKeyPairSync('ec', {
namedCurve: 'sect239k1'
});
const sign = createSign('SHA256');
sign.write('some data to sign');
sign.end();
const signature = sign.sign(privateKey, 'hex');
const verify = createVerify('SHA256');
verify.write('some data to sign');
verify.end();
console.log(verify.verify(publicKey, signature, 'hex'));
// Prints: true
```
Example: Using the [`sign.update()`][] and [`verify.update()`][] methods:
```mjs
const {
generateKeyPairSync,
createSign,
createVerify
} = await import('crypto');
const { privateKey, publicKey } = generateKeyPairSync('rsa', {
modulusLength: 2048,
});
const sign = createSign('SHA256');
sign.update('some data to sign');
sign.end();
const signature = sign.sign(privateKey);
const verify = createVerify('SHA256');
verify.update('some data to sign');
verify.end();
console.log(verify.verify(publicKey, signature));
// Prints: true
```
```cjs
const {
generateKeyPairSync,
createSign,
createVerify,
} = require('crypto');
const { privateKey, publicKey } = generateKeyPairSync('rsa', {
modulusLength: 2048,
});
const sign = createSign('SHA256');
sign.update('some data to sign');
sign.end();
const signature = sign.sign(privateKey);
const verify = createVerify('SHA256');
verify.update('some data to sign');
verify.end();
console.log(verify.verify(publicKey, signature));
// Prints: true
```
### `sign.sign(privateKey[, outputEncoding])`
<!-- YAML
added: v0.1.92
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The privateKey can also be an ArrayBuffer and CryptoKey.
- version:
- v13.2.0
- v12.16.0
pr-url: https://github.com/nodejs/node/pull/29292
description: This function now supports IEEE-P1363 DSA and ECDSA signatures.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26960
description: This function now supports RSA-PSS keys.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: This function now supports key objects.
- version: v8.0.0
pr-url: https://github.com/nodejs/node/pull/11705
description: Support for RSASSA-PSS and additional options was added.
-->
<!--lint disable maximum-line-length remark-lint-->
* `privateKey` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `dsaEncoding` {string}
* `padding` {integer}
* `saltLength` {integer}
* `outputEncoding` {string} The [encoding][] of the return value.
* Returns: {Buffer | string}
<!--lint enable maximum-line-length remark-lint-->
Calculates the signature on all the data passed through using either
[`sign.update()`][] or [`sign.write()`][stream-writable-write].
If `privateKey` is not a [`KeyObject`][], this function behaves as if
`privateKey` had been passed to [`crypto.createPrivateKey()`][]. If it is an
object, the following additional properties can be passed:
* `dsaEncoding` {string} For DSA and ECDSA, this option specifies the
format of the generated signature. It can be one of the following:
* `'der'` (default): DER-encoded ASN.1 signature structure encoding `(r, s)`.
* `'ieee-p1363'`: Signature format `r || s` as proposed in IEEE-P1363.
* `padding` {integer} Optional padding value for RSA, one of the following:
* `crypto.constants.RSA_PKCS1_PADDING` (default)
* `crypto.constants.RSA_PKCS1_PSS_PADDING`
`RSA_PKCS1_PSS_PADDING` will use MGF1 with the same hash function
used to sign the message as specified in section 3.1 of [RFC 4055][], unless
an MGF1 hash function has been specified as part of the key in compliance with
section 3.3 of [RFC 4055][].
* `saltLength` {integer} Salt length for when padding is
`RSA_PKCS1_PSS_PADDING`. The special value
`crypto.constants.RSA_PSS_SALTLEN_DIGEST` sets the salt length to the digest
size, `crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN` (default) sets it to the
maximum permissible value.
If `outputEncoding` is provided a string is returned; otherwise a [`Buffer`][]
is returned.
The `Sign` object can not be again used after `sign.sign()` method has been
called. Multiple calls to `sign.sign()` will result in an error being thrown.
### `sign.update(data[, inputEncoding])`
<!-- YAML
added: v0.1.92
changes:
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `data` {string|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the `data` string.
Updates the `Sign` content with the given `data`, the encoding of which
is given in `inputEncoding`.
If `encoding` is not provided, and the `data` is a string, an
encoding of `'utf8'` is enforced. If `data` is a [`Buffer`][], `TypedArray`, or
`DataView`, then `inputEncoding` is ignored.
This can be called many times with new data as it is streamed.
## Class: `Verify`
<!-- YAML
added: v0.1.92
-->
* Extends: {stream.Writable}
The `Verify` class is a utility for verifying signatures. It can be used in one
of two ways:
* As a writable [stream][] where written data is used to validate against the
supplied signature, or
* Using the [`verify.update()`][] and [`verify.verify()`][] methods to verify
the signature.
The [`crypto.createVerify()`][] method is used to create `Verify` instances.
`Verify` objects are not to be created directly using the `new` keyword.
See [`Sign`][] for examples.
### `verify.update(data[, inputEncoding])`
<!-- YAML
added: v0.1.92
changes:
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default `inputEncoding` changed from `binary` to `utf8`.
-->
* `data` {string|Buffer|TypedArray|DataView}
* `inputEncoding` {string} The [encoding][] of the `data` string.
Updates the `Verify` content with the given `data`, the encoding of which
is given in `inputEncoding`.
If `inputEncoding` is not provided, and the `data` is a string, an
encoding of `'utf8'` is enforced. If `data` is a [`Buffer`][], `TypedArray`, or
`DataView`, then `inputEncoding` is ignored.
This can be called many times with new data as it is streamed.
### `verify.verify(object, signature[, signatureEncoding])`
<!-- YAML
added: v0.1.92
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The object can also be an ArrayBuffer and CryptoKey.
- version:
- v13.2.0
- v12.16.0
pr-url: https://github.com/nodejs/node/pull/29292
description: This function now supports IEEE-P1363 DSA and ECDSA signatures.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26960
description: This function now supports RSA-PSS keys.
- version: v11.7.0
pr-url: https://github.com/nodejs/node/pull/25217
description: The key can now be a private key.
- version: v8.0.0
pr-url: https://github.com/nodejs/node/pull/11705
description: Support for RSASSA-PSS and additional options was added.
-->
<!--lint disable maximum-line-length remark-lint-->
* `object` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `dsaEncoding` {string}
* `padding` {integer}
* `saltLength` {integer}
* `signature` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `signatureEncoding` {string} The [encoding][] of the `signature` string.
* Returns: {boolean} `true` or `false` depending on the validity of the
signature for the data and public key.
<!--lint enable maximum-line-length remark-lint-->
Verifies the provided data using the given `object` and `signature`.
If `object` is not a [`KeyObject`][], this function behaves as if
`object` had been passed to [`crypto.createPublicKey()`][]. If it is an
object, the following additional properties can be passed:
* `dsaEncoding` {string} For DSA and ECDSA, this option specifies the
format of the signature. It can be one of the following:
* `'der'` (default): DER-encoded ASN.1 signature structure encoding `(r, s)`.
* `'ieee-p1363'`: Signature format `r || s` as proposed in IEEE-P1363.
* `padding` {integer} Optional padding value for RSA, one of the following:
* `crypto.constants.RSA_PKCS1_PADDING` (default)
* `crypto.constants.RSA_PKCS1_PSS_PADDING`
`RSA_PKCS1_PSS_PADDING` will use MGF1 with the same hash function
used to verify the message as specified in section 3.1 of [RFC 4055][], unless
an MGF1 hash function has been specified as part of the key in compliance with
section 3.3 of [RFC 4055][].
* `saltLength` {integer} Salt length for when padding is
`RSA_PKCS1_PSS_PADDING`. The special value
`crypto.constants.RSA_PSS_SALTLEN_DIGEST` sets the salt length to the digest
size, `crypto.constants.RSA_PSS_SALTLEN_AUTO` (default) causes it to be
determined automatically.
The `signature` argument is the previously calculated signature for the data, in
the `signatureEncoding`.
If a `signatureEncoding` is specified, the `signature` is expected to be a
string; otherwise `signature` is expected to be a [`Buffer`][],
`TypedArray`, or `DataView`.
The `verify` object can not be used again after `verify.verify()` has been
called. Multiple calls to `verify.verify()` will result in an error being
thrown.
Because public keys can be derived from private keys, a private key may
be passed instead of a public key.
## Class: `X509Certificate`
<!-- YAML
added: v15.6.0
-->
Encapsulates an X509 certificate and provides read-only access to
its information.
```mjs
const { X509Certificate } = await import('crypto');
const x509 = new X509Certificate('{... pem encoded cert ...}');
console.log(x509.subject);
```
```cjs
const { X509Certificate } = require('crypto');
const x509 = new X509Certificate('{... pem encoded cert ...}');
console.log(x509.subject);
```
### `new X509Certificate(buffer)`
<!-- YAML
added: v15.6.0
-->
* `buffer` {string|TypedArray|Buffer|DataView} A PEM or DER encoded
X509 Certificate.
### `x509.ca`
<!-- YAML
added: v15.6.0
-->
* Type: {boolean} Will be `true` if this is a Certificate Authority (CA)
certificate.
### `x509.checkEmail(email[, options])`
<!-- YAML
added: v15.6.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41600
description: The subject option now defaults to `'default'`.
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41599
description: The `wildcards`, `partialWildcards`, `multiLabelWildcards`, and
`singleLabelSubdomains` options have been removed since they
had no effect.
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41569
description: The subject option can now be set to `'default'`.
-->
* `email` {string}
* `options` {Object}
* `subject` {string} `'default'`, `'always'`, or `'never'`.
**Default:** `'default'`.
* Returns: {string|undefined} Returns `email` if the certificate matches,
`undefined` if it does not.
Checks whether the certificate matches the given email address.
If the `'subject'` option is undefined or set to `'default'`, the certificate
subject is only considered if the subject alternative name extension either does
not exist or does not contain any email addresses.
If the `'subject'` option is set to `'always'` and if the subject alternative
name extension either does not exist or does not contain a matching email
address, the certificate subject is considered.
If the `'subject'` option is set to `'never'`, the certificate subject is never
considered, even if the certificate contains no subject alternative names.
### `x509.checkHost(name[, options])`
<!-- YAML
added: v15.6.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41600
description: The subject option now defaults to `'default'`.
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41569
description: The subject option can now be set to `'default'`.
-->
* `name` {string}
* `options` {Object}
* `subject` {string} `'default'`, `'always'`, or `'never'`.
**Default:** `'default'`.
* `wildcards` {boolean} **Default:** `true`.
* `partialWildcards` {boolean} **Default:** `true`.
* `multiLabelWildcards` {boolean} **Default:** `false`.
* `singleLabelSubdomains` {boolean} **Default:** `false`.
* Returns: {string|undefined} Returns a subject name that matches `name`,
or `undefined` if no subject name matches `name`.
Checks whether the certificate matches the given host name.
If the certificate matches the given host name, the matching subject name is
returned. The returned name might be an exact match (e.g., `foo.example.com`)
or it might contain wildcards (e.g., `*.example.com`). Because host name
comparisons are case-insensitive, the returned subject name might also differ
from the given `name` in capitalization.
If the `'subject'` option is undefined or set to `'default'`, the certificate
subject is only considered if the subject alternative name extension either does
not exist or does not contain any DNS names. This behavior is consistent with
[RFC 2818][] ("HTTP Over TLS").
If the `'subject'` option is set to `'always'` and if the subject alternative
name extension either does not exist or does not contain a matching DNS name,
the certificate subject is considered.
If the `'subject'` option is set to `'never'`, the certificate subject is never
considered, even if the certificate contains no subject alternative names.
### `x509.checkIP(ip)`
<!-- YAML
added: v15.6.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41571
description: The `options` argument has been removed since it had no effect.
-->
* `ip` {string}
* Returns: {string|undefined} Returns `ip` if the certificate matches,
`undefined` if it does not.
Checks whether the certificate matches the given IP address (IPv4 or IPv6).
Only [RFC 5280][] `iPAddress` subject alternative names are considered, and they
must match the given `ip` address exactly. Other subject alternative names as
well as the subject field of the certificate are ignored.
### `x509.checkIssued(otherCert)`
<!-- YAML
added: v15.6.0
-->
* `otherCert` {X509Certificate}
* Returns: {boolean}
Checks whether this certificate was issued by the given `otherCert`.
### `x509.checkPrivateKey(privateKey)`
<!-- YAML
added: v15.6.0
-->
* `privateKey` {KeyObject} A private key.
* Returns: {boolean}
Checks whether the public key for this certificate is consistent with
the given private key.
### `x509.fingerprint`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The SHA-1 fingerprint of this certificate.
### `x509.fingerprint256`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The SHA-256 fingerprint of this certificate.
### `x509.fingerprint512`
<!-- YAML
added: v17.2.0
-->
* Type: {string}
The SHA-512 fingerprint of this certificate.
### `x509.infoAccess`
<!-- YAML
added: v15.6.0
changes:
- version:
- v17.3.1
- v16.13.2
pr-url: https://github.com/nodejs-private/node-private/pull/300
description: Parts of this string may be encoded as JSON string literals
in response to CVE-2021-44532.
-->
* Type: {string}
A textual representation of the certificate's authority information access
extension.
This is a line feed separated list of access descriptions. Each line begins with
the access method and the kind of the access location, followed by a colon and
the value associated with the access location.
After the prefix denoting the access method and the kind of the access location,
the remainder of each line might be enclosed in quotes to indicate that the
value is a JSON string literal. For backward compatibility, Node.js only uses
JSON string literals within this property when necessary to avoid ambiguity.
Third-party code should be prepared to handle both possible entry formats.
### `x509.issuer`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The issuer identification included in this certificate.
### `x509.issuerCertificate`
<!-- YAML
added: v15.9.0
-->
* Type: {X509Certificate}
The issuer certificate or `undefined` if the issuer certificate is not
available.
### `x509.keyUsage`
<!-- YAML
added: v15.6.0
-->
* Type: {string\[]}
An array detailing the key usages for this certificate.
### `x509.publicKey`
<!-- YAML
added: v15.6.0
-->
* Type: {KeyObject}
The public key {KeyObject} for this certificate.
### `x509.raw`
<!-- YAML
added: v15.6.0
-->
* Type: {Buffer}
A `Buffer` containing the DER encoding of this certificate.
### `x509.serialNumber`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The serial number of this certificate.
### `x509.subject`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The complete subject of this certificate.
### `x509.subjectAltName`
<!-- YAML
added: v15.6.0
changes:
- version:
- v17.3.1
- v16.13.2
pr-url: https://github.com/nodejs-private/node-private/pull/300
description: Parts of this string may be encoded as JSON string literals
in response to CVE-2021-44532.
-->
* Type: {string}
The subject alternative name specified for this certificate.
This is a comma-separated list of subject alternative names. Each entry begins
with a string identifying the kind of the subject alternative name followed by
a colon and the value associated with the entry.
Earlier versions of Node.js incorrectly assumed that it is safe to split this
property at the two-character sequence `', '` (see [CVE-2021-44532][]). However,
both malicious and legitimate certificates can contain subject alternative names
that include this sequence when represented as a string.
After the prefix denoting the type of the entry, the remainder of each entry
might be enclosed in quotes to indicate that the value is a JSON string literal.
For backward compatibility, Node.js only uses JSON string literals within this
property when necessary to avoid ambiguity. Third-party code should be prepared
to handle both possible entry formats.
### `x509.toJSON()`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
There is no standard JSON encoding for X509 certificates. The
`toJSON()` method returns a string containing the PEM encoded
certificate.
### `x509.toLegacyObject()`
<!-- YAML
added: v15.6.0
-->
* Type: {Object}
Returns information about this certificate using the legacy
[certificate object][] encoding.
### `x509.toString()`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
Returns the PEM-encoded certificate.
### `x509.validFrom`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The date/time from which this certificate is considered valid.
### `x509.validTo`
<!-- YAML
added: v15.6.0
-->
* Type: {string}
The date/time until which this certificate is considered valid.
### `x509.verify(publicKey)`
<!-- YAML
added: v15.6.0
-->
* `publicKey` {KeyObject} A public key.
* Returns: {boolean}
Verifies that this certificate was signed by the given public key.
Does not perform any other validation checks on the certificate.
## `crypto` module methods and properties
### `crypto.constants`
<!-- YAML
added: v6.3.0
-->
* Returns: {Object} An object containing commonly used constants for crypto and
security related operations. The specific constants currently defined are
described in [Crypto constants][].
### `crypto.DEFAULT_ENCODING`
<!-- YAML
added: v0.9.3
deprecated: v10.0.0
-->
> Stability: 0 - Deprecated
The default encoding to use for functions that can take either strings
or [buffers][`Buffer`]. The default value is `'buffer'`, which makes methods
default to [`Buffer`][] objects.
The `crypto.DEFAULT_ENCODING` mechanism is provided for backward compatibility
with legacy programs that expect `'latin1'` to be the default encoding.
New applications should expect the default to be `'buffer'`.
This property is deprecated.
### `crypto.fips`
<!-- YAML
added: v6.0.0
deprecated: v10.0.0
-->
> Stability: 0 - Deprecated
Property for checking and controlling whether a FIPS compliant crypto provider
is currently in use. Setting to true requires a FIPS build of Node.js.
This property is deprecated. Please use `crypto.setFips()` and
`crypto.getFips()` instead.
### `crypto.checkPrime(candidate[, options, [callback]])`
<!-- YAML
added: v15.8.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
-->
* `candidate` {ArrayBuffer|SharedArrayBuffer|TypedArray|Buffer|DataView|bigint}
A possible prime encoded as a sequence of big endian octets of arbitrary
length.
* `options` {Object}
* `checks` {number} The number of Miller-Rabin probabilistic primality
iterations to perform. When the value is `0` (zero), a number of checks
is used that yields a false positive rate of at most 2<sup>-64</sup> for
random input. Care must be used when selecting a number of checks. Refer
to the OpenSSL documentation for the [`BN_is_prime_ex`][] function `nchecks`
options for more details. **Default:** `0`
* `callback` {Function}
* `err` {Error} Set to an {Error} object if an error occurred during check.
* `result` {boolean} `true` if the candidate is a prime with an error
probability less than `0.25 ** options.checks`.
Checks the primality of the `candidate`.
### `crypto.checkPrimeSync(candidate[, options])`
<!-- YAML
added: v15.8.0
-->
* `candidate` {ArrayBuffer|SharedArrayBuffer|TypedArray|Buffer|DataView|bigint}
A possible prime encoded as a sequence of big endian octets of arbitrary
length.
* `options` {Object}
* `checks` {number} The number of Miller-Rabin probabilistic primality
iterations to perform. When the value is `0` (zero), a number of checks
is used that yields a false positive rate of at most 2<sup>-64</sup> for
random input. Care must be used when selecting a number of checks. Refer
to the OpenSSL documentation for the [`BN_is_prime_ex`][] function `nchecks`
options for more details. **Default:** `0`
* Returns: {boolean} `true` if the candidate is a prime with an error
probability less than `0.25 ** options.checks`.
Checks the primality of the `candidate`.
### `crypto.createCipher(algorithm, password[, options])`
<!-- YAML
added: v0.1.94
deprecated: v10.0.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The password argument can be an ArrayBuffer and is limited to
a maximum of 2 ** 31 - 1 bytes.
- version: v10.10.0
pr-url: https://github.com/nodejs/node/pull/21447
description: Ciphers in OCB mode are now supported.
- version: v10.2.0
pr-url: https://github.com/nodejs/node/pull/20235
description: The `authTagLength` option can now be used to produce shorter
authentication tags in GCM mode and defaults to 16 bytes.
-->
> Stability: 0 - Deprecated: Use [`crypto.createCipheriv()`][] instead.
* `algorithm` {string}
* `password` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `options` {Object} [`stream.transform` options][]
* Returns: {Cipher}
Creates and returns a `Cipher` object that uses the given `algorithm` and
`password`.
The `options` argument controls stream behavior and is optional except when a
cipher in CCM or OCB mode is used (e.g. `'aes-128-ccm'`). In that case, the
`authTagLength` option is required and specifies the length of the
authentication tag in bytes, see [CCM mode][]. In GCM mode, the `authTagLength`
option is not required but can be used to set the length of the authentication
tag that will be returned by `getAuthTag()` and defaults to 16 bytes.
The `algorithm` is dependent on OpenSSL, examples are `'aes192'`, etc. On
recent OpenSSL releases, `openssl list -cipher-algorithms`
(`openssl list-cipher-algorithms` for older versions of OpenSSL) will
display the available cipher algorithms.
The `password` is used to derive the cipher key and initialization vector (IV).
The value must be either a `'latin1'` encoded string, a [`Buffer`][], a
`TypedArray`, or a `DataView`.
The implementation of `crypto.createCipher()` derives keys using the OpenSSL
function [`EVP_BytesToKey`][] with the digest algorithm set to MD5, one
iteration, and no salt. The lack of salt allows dictionary attacks as the same
password always creates the same key. The low iteration count and
non-cryptographically secure hash algorithm allow passwords to be tested very
rapidly.
In line with OpenSSL's recommendation to use a more modern algorithm instead of
[`EVP_BytesToKey`][] it is recommended that developers derive a key and IV on
their own using [`crypto.scrypt()`][] and to use [`crypto.createCipheriv()`][]
to create the `Cipher` object. Users should not use ciphers with counter mode
(e.g. CTR, GCM, or CCM) in `crypto.createCipher()`. A warning is emitted when
they are used in order to avoid the risk of IV reuse that causes
vulnerabilities. For the case when IV is reused in GCM, see [Nonce-Disrespecting
Adversaries][] for details.
### `crypto.createCipheriv(algorithm, key, iv[, options])`
<!-- YAML
added: v0.1.94
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The password and iv arguments can be an ArrayBuffer and are
each limited to a maximum of 2 ** 31 - 1 bytes.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: The `key` argument can now be a `KeyObject`.
- version:
- v11.2.0
- v10.17.0
pr-url: https://github.com/nodejs/node/pull/24081
description: The cipher `chacha20-poly1305` is now supported.
- version: v10.10.0
pr-url: https://github.com/nodejs/node/pull/21447
description: Ciphers in OCB mode are now supported.
- version: v10.2.0
pr-url: https://github.com/nodejs/node/pull/20235
description: The `authTagLength` option can now be used to produce shorter
authentication tags in GCM mode and defaults to 16 bytes.
- version: v9.9.0
pr-url: https://github.com/nodejs/node/pull/18644
description: The `iv` parameter may now be `null` for ciphers which do not
need an initialization vector.
-->
* `algorithm` {string}
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `iv` {string|ArrayBuffer|Buffer|TypedArray|DataView|null}
* `options` {Object} [`stream.transform` options][]
* Returns: {Cipher}
Creates and returns a `Cipher` object, with the given `algorithm`, `key` and
initialization vector (`iv`).
The `options` argument controls stream behavior and is optional except when a
cipher in CCM or OCB mode is used (e.g. `'aes-128-ccm'`). In that case, the
`authTagLength` option is required and specifies the length of the
authentication tag in bytes, see [CCM mode][]. In GCM mode, the `authTagLength`
option is not required but can be used to set the length of the authentication
tag that will be returned by `getAuthTag()` and defaults to 16 bytes.
The `algorithm` is dependent on OpenSSL, examples are `'aes192'`, etc. On
recent OpenSSL releases, `openssl list -cipher-algorithms`
(`openssl list-cipher-algorithms` for older versions of OpenSSL) will
display the available cipher algorithms.
The `key` is the raw key used by the `algorithm` and `iv` is an
[initialization vector][]. Both arguments must be `'utf8'` encoded strings,
[Buffers][`Buffer`], `TypedArray`, or `DataView`s. The `key` may optionally be
a [`KeyObject`][] of type `secret`. If the cipher does not need
an initialization vector, `iv` may be `null`.
When passing strings for `key` or `iv`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
Initialization vectors should be unpredictable and unique; ideally, they will be
cryptographically random. They do not have to be secret: IVs are typically just
added to ciphertext messages unencrypted. It may sound contradictory that
something has to be unpredictable and unique, but does not have to be secret;
remember that an attacker must not be able to predict ahead of time what a
given IV will be.
### `crypto.createDecipher(algorithm, password[, options])`
<!-- YAML
added: v0.1.94
deprecated: v10.0.0
changes:
- version: v10.10.0
pr-url: https://github.com/nodejs/node/pull/21447
description: Ciphers in OCB mode are now supported.
-->
> Stability: 0 - Deprecated: Use [`crypto.createDecipheriv()`][] instead.
* `algorithm` {string}
* `password` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `options` {Object} [`stream.transform` options][]
* Returns: {Decipher}
Creates and returns a `Decipher` object that uses the given `algorithm` and
`password` (key).
The `options` argument controls stream behavior and is optional except when a
cipher in CCM or OCB mode is used (e.g. `'aes-128-ccm'`). In that case, the
`authTagLength` option is required and specifies the length of the
authentication tag in bytes, see [CCM mode][].
The implementation of `crypto.createDecipher()` derives keys using the OpenSSL
function [`EVP_BytesToKey`][] with the digest algorithm set to MD5, one
iteration, and no salt. The lack of salt allows dictionary attacks as the same
password always creates the same key. The low iteration count and
non-cryptographically secure hash algorithm allow passwords to be tested very
rapidly.
In line with OpenSSL's recommendation to use a more modern algorithm instead of
[`EVP_BytesToKey`][] it is recommended that developers derive a key and IV on
their own using [`crypto.scrypt()`][] and to use [`crypto.createDecipheriv()`][]
to create the `Decipher` object.
### `crypto.createDecipheriv(algorithm, key, iv[, options])`
<!-- YAML
added: v0.1.94
changes:
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: The `key` argument can now be a `KeyObject`.
- version:
- v11.2.0
- v10.17.0
pr-url: https://github.com/nodejs/node/pull/24081
description: The cipher `chacha20-poly1305` is now supported.
- version: v10.10.0
pr-url: https://github.com/nodejs/node/pull/21447
description: Ciphers in OCB mode are now supported.
- version: v10.2.0
pr-url: https://github.com/nodejs/node/pull/20039
description: The `authTagLength` option can now be used to restrict accepted
GCM authentication tag lengths.
- version: v9.9.0
pr-url: https://github.com/nodejs/node/pull/18644
description: The `iv` parameter may now be `null` for ciphers which do not
need an initialization vector.
-->
* `algorithm` {string}
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `iv` {string|ArrayBuffer|Buffer|TypedArray|DataView|null}
* `options` {Object} [`stream.transform` options][]
* Returns: {Decipher}
Creates and returns a `Decipher` object that uses the given `algorithm`, `key`
and initialization vector (`iv`).
The `options` argument controls stream behavior and is optional except when a
cipher in CCM or OCB mode is used (e.g. `'aes-128-ccm'`). In that case, the
`authTagLength` option is required and specifies the length of the
authentication tag in bytes, see [CCM mode][]. In GCM mode, the `authTagLength`
option is not required but can be used to restrict accepted authentication tags
to those with the specified length.
The `algorithm` is dependent on OpenSSL, examples are `'aes192'`, etc. On
recent OpenSSL releases, `openssl list -cipher-algorithms`
(`openssl list-cipher-algorithms` for older versions of OpenSSL) will
display the available cipher algorithms.
The `key` is the raw key used by the `algorithm` and `iv` is an
[initialization vector][]. Both arguments must be `'utf8'` encoded strings,
[Buffers][`Buffer`], `TypedArray`, or `DataView`s. The `key` may optionally be
a [`KeyObject`][] of type `secret`. If the cipher does not need
an initialization vector, `iv` may be `null`.
When passing strings for `key` or `iv`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
Initialization vectors should be unpredictable and unique; ideally, they will be
cryptographically random. They do not have to be secret: IVs are typically just
added to ciphertext messages unencrypted. It may sound contradictory that
something has to be unpredictable and unique, but does not have to be secret;
remember that an attacker must not be able to predict ahead of time what a given
IV will be.
### `crypto.createDiffieHellman(prime[, primeEncoding][, generator][, generatorEncoding])`
<!-- YAML
added: v0.11.12
changes:
- version: v8.0.0
pr-url: https://github.com/nodejs/node/pull/12223
description: The `prime` argument can be any `TypedArray` or `DataView` now.
- version: v8.0.0
pr-url: https://github.com/nodejs/node/pull/11983
description: The `prime` argument can be a `Uint8Array` now.
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default for the encoding parameters changed
from `binary` to `utf8`.
-->
* `prime` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `primeEncoding` {string} The [encoding][] of the `prime` string.
* `generator` {number|string|ArrayBuffer|Buffer|TypedArray|DataView}
**Default:** `2`
* `generatorEncoding` {string} The [encoding][] of the `generator` string.
* Returns: {DiffieHellman}
Creates a `DiffieHellman` key exchange object using the supplied `prime` and an
optional specific `generator`.
The `generator` argument can be a number, string, or [`Buffer`][]. If
`generator` is not specified, the value `2` is used.
If `primeEncoding` is specified, `prime` is expected to be a string; otherwise
a [`Buffer`][], `TypedArray`, or `DataView` is expected.
If `generatorEncoding` is specified, `generator` is expected to be a string;
otherwise a number, [`Buffer`][], `TypedArray`, or `DataView` is expected.
### `crypto.createDiffieHellman(primeLength[, generator])`
<!-- YAML
added: v0.5.0
-->
* `primeLength` {number}
* `generator` {number} **Default:** `2`
* Returns: {DiffieHellman}
Creates a `DiffieHellman` key exchange object and generates a prime of
`primeLength` bits using an optional specific numeric `generator`.
If `generator` is not specified, the value `2` is used.
### `crypto.createDiffieHellmanGroup(name)`
<!-- YAML
added: v0.9.3
-->
* `name` {string}
* Returns: {DiffieHellmanGroup}
An alias for [`crypto.getDiffieHellman()`][]
### `crypto.createECDH(curveName)`
<!-- YAML
added: v0.11.14
-->
* `curveName` {string}
* Returns: {ECDH}
Creates an Elliptic Curve Diffie-Hellman (`ECDH`) key exchange object using a
predefined curve specified by the `curveName` string. Use
[`crypto.getCurves()`][] to obtain a list of available curve names. On recent
OpenSSL releases, `openssl ecparam -list_curves` will also display the name
and description of each available elliptic curve.
### `crypto.createHash(algorithm[, options])`
<!-- YAML
added: v0.1.92
changes:
- version: v12.8.0
pr-url: https://github.com/nodejs/node/pull/28805
description: The `outputLength` option was added for XOF hash functions.
-->
* `algorithm` {string}
* `options` {Object} [`stream.transform` options][]
* Returns: {Hash}
Creates and returns a `Hash` object that can be used to generate hash digests
using the given `algorithm`. Optional `options` argument controls stream
behavior. For XOF hash functions such as `'shake256'`, the `outputLength` option
can be used to specify the desired output length in bytes.
The `algorithm` is dependent on the available algorithms supported by the
version of OpenSSL on the platform. Examples are `'sha256'`, `'sha512'`, etc.
On recent releases of OpenSSL, `openssl list -digest-algorithms`
(`openssl list-message-digest-algorithms` for older versions of OpenSSL) will
display the available digest algorithms.
Example: generating the sha256 sum of a file
```mjs
import {
createReadStream
} from 'fs';
import { argv } from 'process';
const {
createHash
} = await import('crypto');
const filename = argv[2];
const hash = createHash('sha256');
const input = createReadStream(filename);
input.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = input.read();
if (data)
hash.update(data);
else {
console.log(`${hash.digest('hex')} ${filename}`);
}
});
```
```cjs
const {
createReadStream,
} = require('fs');
const {
createHash,
} = require('crypto');
const { argv } = require('process');
const filename = argv[2];
const hash = createHash('sha256');
const input = createReadStream(filename);
input.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = input.read();
if (data)
hash.update(data);
else {
console.log(`${hash.digest('hex')} ${filename}`);
}
});
```
### `crypto.createHmac(algorithm, key[, options])`
<!-- YAML
added: v0.1.94
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The key can also be an ArrayBuffer or CryptoKey. The
encoding option was added. The key cannot contain
more than 2 ** 32 - 1 bytes.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: The `key` argument can now be a `KeyObject`.
-->
* `algorithm` {string}
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `options` {Object} [`stream.transform` options][]
* `encoding` {string} The string encoding to use when `key` is a string.
* Returns: {Hmac}
Creates and returns an `Hmac` object that uses the given `algorithm` and `key`.
Optional `options` argument controls stream behavior.
The `algorithm` is dependent on the available algorithms supported by the
version of OpenSSL on the platform. Examples are `'sha256'`, `'sha512'`, etc.
On recent releases of OpenSSL, `openssl list -digest-algorithms`
(`openssl list-message-digest-algorithms` for older versions of OpenSSL) will
display the available digest algorithms.
The `key` is the HMAC key used to generate the cryptographic HMAC hash. If it is
a [`KeyObject`][], its type must be `secret`.
Example: generating the sha256 HMAC of a file
```mjs
import {
createReadStream
} from 'fs';
import { argv } from 'process';
const {
createHmac
} = await import('crypto');
const filename = argv[2];
const hmac = createHmac('sha256', 'a secret');
const input = createReadStream(filename);
input.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = input.read();
if (data)
hmac.update(data);
else {
console.log(`${hmac.digest('hex')} ${filename}`);
}
});
```
```cjs
const {
createReadStream,
} = require('fs');
const {
createHmac,
} = require('crypto');
const { argv } = require('process');
const filename = argv[2];
const hmac = createHmac('sha256', 'a secret');
const input = createReadStream(filename);
input.on('readable', () => {
// Only one element is going to be produced by the
// hash stream.
const data = input.read();
if (data)
hmac.update(data);
else {
console.log(`${hmac.digest('hex')} ${filename}`);
}
});
```
### `crypto.createPrivateKey(key)`
<!-- YAML
added: v11.6.0
changes:
- version: v15.12.0
pr-url: https://github.com/nodejs/node/pull/37254
description: The key can also be a JWK object.
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The key can also be an ArrayBuffer. The encoding option was
added. The key cannot contain more than 2 ** 32 - 1 bytes.
-->
<!--lint disable maximum-line-length remark-lint-->
* `key` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView}
* `key`: {string|ArrayBuffer|Buffer|TypedArray|DataView|Object} The key
material, either in PEM, DER, or JWK format.
* `format`: {string} Must be `'pem'`, `'der'`, or '`'jwk'`.
**Default:** `'pem'`.
* `type`: {string} Must be `'pkcs1'`, `'pkcs8'` or `'sec1'`. This option is
required only if the `format` is `'der'` and ignored otherwise.
* `passphrase`: {string | Buffer} The passphrase to use for decryption.
* `encoding`: {string} The string encoding to use when `key` is a string.
* Returns: {KeyObject}
<!--lint enable maximum-line-length remark-lint-->
Creates and returns a new key object containing a private key. If `key` is a
string or `Buffer`, `format` is assumed to be `'pem'`; otherwise, `key`
must be an object with the properties described above.
If the private key is encrypted, a `passphrase` must be specified. The length
of the passphrase is limited to 1024 bytes.
### `crypto.createPublicKey(key)`
<!-- YAML
added: v11.6.0
changes:
- version: v15.12.0
pr-url: https://github.com/nodejs/node/pull/37254
description: The key can also be a JWK object.
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The key can also be an ArrayBuffer. The encoding option was
added. The key cannot contain more than 2 ** 32 - 1 bytes.
- version: v11.13.0
pr-url: https://github.com/nodejs/node/pull/26278
description: The `key` argument can now be a `KeyObject` with type
`private`.
- version: v11.7.0
pr-url: https://github.com/nodejs/node/pull/25217
description: The `key` argument can now be a private key.
-->
<!--lint disable maximum-line-length remark-lint-->
* `key` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView}
* `key`: {string|ArrayBuffer|Buffer|TypedArray|DataView|Object} The key
material, either in PEM, DER, or JWK format.
* `format`: {string} Must be `'pem'`, `'der'`, or `'jwk'`.
**Default:** `'pem'`.
* `type`: {string} Must be `'pkcs1'` or `'spki'`. This option is
required only if the `format` is `'der'` and ignored otherwise.
* `encoding` {string} The string encoding to use when `key` is a string.
* Returns: {KeyObject}
<!--lint enable maximum-line-length remark-lint-->
Creates and returns a new key object containing a public key. If `key` is a
string or `Buffer`, `format` is assumed to be `'pem'`; if `key` is a `KeyObject`
with type `'private'`, the public key is derived from the given private key;
otherwise, `key` must be an object with the properties described above.
If the format is `'pem'`, the `'key'` may also be an X.509 certificate.
Because public keys can be derived from private keys, a private key may be
passed instead of a public key. In that case, this function behaves as if
[`crypto.createPrivateKey()`][] had been called, except that the type of the
returned `KeyObject` will be `'public'` and that the private key cannot be
extracted from the returned `KeyObject`. Similarly, if a `KeyObject` with type
`'private'` is given, a new `KeyObject` with type `'public'` will be returned
and it will be impossible to extract the private key from the returned object.
### `crypto.createSecretKey(key[, encoding])`
<!-- YAML
added: v11.6.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The key can also be an ArrayBuffer or string. The encoding
argument was added. The key cannot contain more than
2 ** 32 - 1 bytes.
-->
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `encoding` {string} The string encoding when `key` is a string.
* Returns: {KeyObject}
Creates and returns a new key object containing a secret key for symmetric
encryption or `Hmac`.
### `crypto.createSign(algorithm[, options])`
<!-- YAML
added: v0.1.92
-->
* `algorithm` {string}
* `options` {Object} [`stream.Writable` options][]
* Returns: {Sign}
Creates and returns a `Sign` object that uses the given `algorithm`. Use
[`crypto.getHashes()`][] to obtain the names of the available digest algorithms.
Optional `options` argument controls the `stream.Writable` behavior.
In some cases, a `Sign` instance can be created using the name of a signature
algorithm, such as `'RSA-SHA256'`, instead of a digest algorithm. This will use
the corresponding digest algorithm. This does not work for all signature
algorithms, such as `'ecdsa-with-SHA256'`, so it is best to always use digest
algorithm names.
### `crypto.createVerify(algorithm[, options])`
<!-- YAML
added: v0.1.92
-->
* `algorithm` {string}
* `options` {Object} [`stream.Writable` options][]
* Returns: {Verify}
Creates and returns a `Verify` object that uses the given algorithm.
Use [`crypto.getHashes()`][] to obtain an array of names of the available
signing algorithms. Optional `options` argument controls the
`stream.Writable` behavior.
In some cases, a `Verify` instance can be created using the name of a signature
algorithm, such as `'RSA-SHA256'`, instead of a digest algorithm. This will use
the corresponding digest algorithm. This does not work for all signature
algorithms, such as `'ecdsa-with-SHA256'`, so it is best to always use digest
algorithm names.
### `crypto.diffieHellman(options)`
<!-- YAML
added:
- v13.9.0
- v12.17.0
-->
* `options`: {Object}
* `privateKey`: {KeyObject}
* `publicKey`: {KeyObject}
* Returns: {Buffer}
Computes the Diffie-Hellman secret based on a `privateKey` and a `publicKey`.
Both keys must have the same `asymmetricKeyType`, which must be one of `'dh'`
(for Diffie-Hellman), `'ec'` (for ECDH), `'x448'`, or `'x25519'` (for ECDH-ES).
### `crypto.generateKey(type, options, callback)`
<!-- YAML
added: v15.0.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
-->
* `type`: {string} The intended use of the generated secret key. Currently
accepted values are `'hmac'` and `'aes'`.
* `options`: {Object}
* `length`: {number} The bit length of the key to generate. This must be a
value greater than 0.
* If `type` is `'hmac'`, the minimum is 1, and the maximum length is
2<sup>31</sup>-1. If the value is not a multiple of 8, the generated
key will be truncated to `Math.floor(length / 8)`.
* If `type` is `'aes'`, the length must be one of `128`, `192`, or `256`.
* `callback`: {Function}
* `err`: {Error}
* `key`: {KeyObject}
Asynchronously generates a new random secret key of the given `length`. The
`type` will determine which validations will be performed on the `length`.
```mjs
const {
generateKey
} = await import('crypto');
generateKey('hmac', { length: 64 }, (err, key) => {
if (err) throw err;
console.log(key.export().toString('hex')); // 46e..........620
});
```
```cjs
const {
generateKey,
} = require('crypto');
generateKey('hmac', { length: 64 }, (err, key) => {
if (err) throw err;
console.log(key.export().toString('hex')); // 46e..........620
});
```
### `crypto.generateKeyPair(type, options, callback)`
<!-- YAML
added: v10.12.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v16.10.0
pr-url: https://github.com/nodejs/node/pull/39927
description: Add ability to define `RSASSA-PSS-params` sequence parameters
for RSA-PSS keys pairs.
- version:
- v13.9.0
- v12.17.0
pr-url: https://github.com/nodejs/node/pull/31178
description: Add support for Diffie-Hellman.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26960
description: Add support for RSA-PSS key pairs.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26774
description: Add ability to generate X25519 and X448 key pairs.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26554
description: Add ability to generate Ed25519 and Ed448 key pairs.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: The `generateKeyPair` and `generateKeyPairSync` functions now
produce key objects if no encoding was specified.
-->
* `type`: {string} Must be `'rsa'`, `'rsa-pss'`, `'dsa'`, `'ec'`, `'ed25519'`,
`'ed448'`, `'x25519'`, `'x448'`, or `'dh'`.
* `options`: {Object}
* `modulusLength`: {number} Key size in bits (RSA, DSA).
* `publicExponent`: {number} Public exponent (RSA). **Default:** `0x10001`.
* `hashAlgorithm`: {string} Name of the message digest (RSA-PSS).
* `mgf1HashAlgorithm`: {string} Name of the message digest used by
MGF1 (RSA-PSS).
* `saltLength`: {number} Minimal salt length in bytes (RSA-PSS).
* `divisorLength`: {number} Size of `q` in bits (DSA).
* `namedCurve`: {string} Name of the curve to use (EC).
* `prime`: {Buffer} The prime parameter (DH).
* `primeLength`: {number} Prime length in bits (DH).
* `generator`: {number} Custom generator (DH). **Default:** `2`.
* `groupName`: {string} Diffie-Hellman group name (DH). See
[`crypto.getDiffieHellman()`][].
* `publicKeyEncoding`: {Object} See [`keyObject.export()`][].
* `privateKeyEncoding`: {Object} See [`keyObject.export()`][].
* `callback`: {Function}
* `err`: {Error}
* `publicKey`: {string | Buffer | KeyObject}
* `privateKey`: {string | Buffer | KeyObject}
Generates a new asymmetric key pair of the given `type`. RSA, RSA-PSS, DSA, EC,
Ed25519, Ed448, X25519, X448, and DH are currently supported.
If a `publicKeyEncoding` or `privateKeyEncoding` was specified, this function
behaves as if [`keyObject.export()`][] had been called on its result. Otherwise,
the respective part of the key is returned as a [`KeyObject`][].
It is recommended to encode public keys as `'spki'` and private keys as
`'pkcs8'` with encryption for long-term storage:
```mjs
const {
generateKeyPair
} = await import('crypto');
generateKeyPair('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'spki',
format: 'pem'
},
privateKeyEncoding: {
type: 'pkcs8',
format: 'pem',
cipher: 'aes-256-cbc',
passphrase: 'top secret'
}
}, (err, publicKey, privateKey) => {
// Handle errors and use the generated key pair.
});
```
```cjs
const {
generateKeyPair,
} = require('crypto');
generateKeyPair('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'spki',
format: 'pem'
},
privateKeyEncoding: {
type: 'pkcs8',
format: 'pem',
cipher: 'aes-256-cbc',
passphrase: 'top secret'
}
}, (err, publicKey, privateKey) => {
// Handle errors and use the generated key pair.
});
```
On completion, `callback` will be called with `err` set to `undefined` and
`publicKey` / `privateKey` representing the generated key pair.
If this method is invoked as its [`util.promisify()`][]ed version, it returns
a `Promise` for an `Object` with `publicKey` and `privateKey` properties.
### `crypto.generateKeyPairSync(type, options)`
<!-- YAML
added: v10.12.0
changes:
- version: v16.10.0
pr-url: https://github.com/nodejs/node/pull/39927
description: Add ability to define `RSASSA-PSS-params` sequence parameters
for RSA-PSS keys pairs.
- version:
- v13.9.0
- v12.17.0
pr-url: https://github.com/nodejs/node/pull/31178
description: Add support for Diffie-Hellman.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26960
description: Add support for RSA-PSS key pairs.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26774
description: Add ability to generate X25519 and X448 key pairs.
- version: v12.0.0
pr-url: https://github.com/nodejs/node/pull/26554
description: Add ability to generate Ed25519 and Ed448 key pairs.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: The `generateKeyPair` and `generateKeyPairSync` functions now
produce key objects if no encoding was specified.
-->
* `type`: {string} Must be `'rsa'`, `'rsa-pss'`, `'dsa'`, `'ec'`, `'ed25519'`,
`'ed448'`, `'x25519'`, `'x448'`, or `'dh'`.
* `options`: {Object}
* `modulusLength`: {number} Key size in bits (RSA, DSA).
* `publicExponent`: {number} Public exponent (RSA). **Default:** `0x10001`.
* `hashAlgorithm`: {string} Name of the message digest (RSA-PSS).
* `mgf1HashAlgorithm`: {string} Name of the message digest used by
MGF1 (RSA-PSS).
* `saltLength`: {number} Minimal salt length in bytes (RSA-PSS).
* `divisorLength`: {number} Size of `q` in bits (DSA).
* `namedCurve`: {string} Name of the curve to use (EC).
* `prime`: {Buffer} The prime parameter (DH).
* `primeLength`: {number} Prime length in bits (DH).
* `generator`: {number} Custom generator (DH). **Default:** `2`.
* `groupName`: {string} Diffie-Hellman group name (DH). See
[`crypto.getDiffieHellman()`][].
* `publicKeyEncoding`: {Object} See [`keyObject.export()`][].
* `privateKeyEncoding`: {Object} See [`keyObject.export()`][].
* Returns: {Object}
* `publicKey`: {string | Buffer | KeyObject}
* `privateKey`: {string | Buffer | KeyObject}
Generates a new asymmetric key pair of the given `type`. RSA, RSA-PSS, DSA, EC,
Ed25519, Ed448, X25519, X448, and DH are currently supported.
If a `publicKeyEncoding` or `privateKeyEncoding` was specified, this function
behaves as if [`keyObject.export()`][] had been called on its result. Otherwise,
the respective part of the key is returned as a [`KeyObject`][].
When encoding public keys, it is recommended to use `'spki'`. When encoding
private keys, it is recommended to use `'pkcs8'` with a strong passphrase,
and to keep the passphrase confidential.
```mjs
const {
generateKeyPairSync
} = await import('crypto');
const {
publicKey,
privateKey,
} = generateKeyPairSync('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'spki',
format: 'pem'
},
privateKeyEncoding: {
type: 'pkcs8',
format: 'pem',
cipher: 'aes-256-cbc',
passphrase: 'top secret'
}
});
```
```cjs
const {
generateKeyPairSync,
} = require('crypto');
const {
publicKey,
privateKey,
} = generateKeyPairSync('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'spki',
format: 'pem'
},
privateKeyEncoding: {
type: 'pkcs8',
format: 'pem',
cipher: 'aes-256-cbc',
passphrase: 'top secret'
}
});
```
The return value `{ publicKey, privateKey }` represents the generated key pair.
When PEM encoding was selected, the respective key will be a string, otherwise
it will be a buffer containing the data encoded as DER.
### `crypto.generateKeySync(type, options)`
<!-- YAML
added: v15.0.0
-->
* `type`: {string} The intended use of the generated secret key. Currently
accepted values are `'hmac'` and `'aes'`.
* `options`: {Object}
* `length`: {number} The bit length of the key to generate.
* If `type` is `'hmac'`, the minimum is 1, and the maximum length is
2<sup>31</sup>-1. If the value is not a multiple of 8, the generated
key will be truncated to `Math.floor(length / 8)`.
* If `type` is `'aes'`, the length must be one of `128`, `192`, or `256`.
* Returns: {KeyObject}
Synchronously generates a new random secret key of the given `length`. The
`type` will determine which validations will be performed on the `length`.
```mjs
const {
generateKeySync
} = await import('crypto');
const key = generateKeySync('hmac', { length: 64 });
console.log(key.export().toString('hex')); // e89..........41e
```
```cjs
const {
generateKeySync,
} = require('crypto');
const key = generateKeySync('hmac', { length: 64 });
console.log(key.export().toString('hex')); // e89..........41e
```
### `crypto.generatePrime(size[, options[, callback]])`
<!-- YAML
added: v15.8.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
-->
* `size` {number} The size (in bits) of the prime to generate.
* `options` {Object}
* `add` {ArrayBuffer|SharedArrayBuffer|TypedArray|Buffer|DataView|bigint}
* `rem` {ArrayBuffer|SharedArrayBuffer|TypedArray|Buffer|DataView|bigint}
* `safe` {boolean} **Default:** `false`.
* `bigint` {boolean} When `true`, the generated prime is returned
as a `bigint`.
* `callback` {Function}
* `err` {Error}
* `prime` {ArrayBuffer|bigint}
Generates a pseudorandom prime of `size` bits.
If `options.safe` is `true`, the prime will be a safe prime -- that is,
`(prime - 1) / 2` will also be a prime.
The `options.add` and `options.rem` parameters can be used to enforce additional
requirements, e.g., for Diffie-Hellman:
* If `options.add` and `options.rem` are both set, the prime will satisfy the
condition that `prime % add = rem`.
* If only `options.add` is set and `options.safe` is not `true`, the prime will
satisfy the condition that `prime % add = 1`.
* If only `options.add` is set and `options.safe` is set to `true`, the prime
will instead satisfy the condition that `prime % add = 3`. This is necessary
because `prime % add = 1` for `options.add > 2` would contradict the condition
enforced by `options.safe`.
* `options.rem` is ignored if `options.add` is not given.
Both `options.add` and `options.rem` must be encoded as big-endian sequences
if given as an `ArrayBuffer`, `SharedArrayBuffer`, `TypedArray`, `Buffer`, or
`DataView`.
By default, the prime is encoded as a big-endian sequence of octets
in an {ArrayBuffer}. If the `bigint` option is `true`, then a {bigint}
is provided.
### `crypto.generatePrimeSync(size[, options])`
<!-- YAML
added: v15.8.0
-->
* `size` {number} The size (in bits) of the prime to generate.
* `options` {Object}
* `add` {ArrayBuffer|SharedArrayBuffer|TypedArray|Buffer|DataView|bigint}
* `rem` {ArrayBuffer|SharedArrayBuffer|TypedArray|Buffer|DataView|bigint}
* `safe` {boolean} **Default:** `false`.
* `bigint` {boolean} When `true`, the generated prime is returned
as a `bigint`.
* Returns: {ArrayBuffer|bigint}
Generates a pseudorandom prime of `size` bits.
If `options.safe` is `true`, the prime will be a safe prime -- that is,
`(prime - 1) / 2` will also be a prime.
The `options.add` and `options.rem` parameters can be used to enforce additional
requirements, e.g., for Diffie-Hellman:
* If `options.add` and `options.rem` are both set, the prime will satisfy the
condition that `prime % add = rem`.
* If only `options.add` is set and `options.safe` is not `true`, the prime will
satisfy the condition that `prime % add = 1`.
* If only `options.add` is set and `options.safe` is set to `true`, the prime
will instead satisfy the condition that `prime % add = 3`. This is necessary
because `prime % add = 1` for `options.add > 2` would contradict the condition
enforced by `options.safe`.
* `options.rem` is ignored if `options.add` is not given.
Both `options.add` and `options.rem` must be encoded as big-endian sequences
if given as an `ArrayBuffer`, `SharedArrayBuffer`, `TypedArray`, `Buffer`, or
`DataView`.
By default, the prime is encoded as a big-endian sequence of octets
in an {ArrayBuffer}. If the `bigint` option is `true`, then a {bigint}
is provided.
### `crypto.getCipherInfo(nameOrNid[, options])`
<!-- YAML
added: v15.0.0
-->
* `nameOrNid`: {string|number} The name or nid of the cipher to query.
* `options`: {Object}
* `keyLength`: {number} A test key length.
* `ivLength`: {number} A test IV length.
* Returns: {Object}
* `name` {string} The name of the cipher
* `nid` {number} The nid of the cipher
* `blockSize` {number} The block size of the cipher in bytes. This property
is omitted when `mode` is `'stream'`.
* `ivLength` {number} The expected or default initialization vector length in
bytes. This property is omitted if the cipher does not use an initialization
vector.
* `keyLength` {number} The expected or default key length in bytes.
* `mode` {string} The cipher mode. One of `'cbc'`, `'ccm'`, `'cfb'`, `'ctr'`,
`'ecb'`, `'gcm'`, `'ocb'`, `'ofb'`, `'stream'`, `'wrap'`, `'xts'`.
Returns information about a given cipher.
Some ciphers accept variable length keys and initialization vectors. By default,
the `crypto.getCipherInfo()` method will return the default values for these
ciphers. To test if a given key length or iv length is acceptable for given
cipher, use the `keyLength` and `ivLength` options. If the given values are
unacceptable, `undefined` will be returned.
### `crypto.getCiphers()`
<!-- YAML
added: v0.9.3
-->
* Returns: {string\[]} An array with the names of the supported cipher
algorithms.
```mjs
const {
getCiphers
} = await import('crypto');
console.log(getCiphers()); // ['aes-128-cbc', 'aes-128-ccm', ...]
```
```cjs
const {
getCiphers,
} = require('crypto');
console.log(getCiphers()); // ['aes-128-cbc', 'aes-128-ccm', ...]
```
### `crypto.getCurves()`
<!-- YAML
added: v2.3.0
-->
* Returns: {string\[]} An array with the names of the supported elliptic curves.
```mjs
const {
getCurves
} = await import('crypto');
console.log(getCurves()); // ['Oakley-EC2N-3', 'Oakley-EC2N-4', ...]
```
```cjs
const {
getCurves,
} = require('crypto');
console.log(getCurves()); // ['Oakley-EC2N-3', 'Oakley-EC2N-4', ...]
```
### `crypto.getDiffieHellman(groupName)`
<!-- YAML
added: v0.7.5
-->
* `groupName` {string}
* Returns: {DiffieHellmanGroup}
Creates a predefined `DiffieHellmanGroup` key exchange object. The
supported groups are: `'modp1'`, `'modp2'`, `'modp5'` (defined in
[RFC 2412][], but see [Caveats][]) and `'modp14'`, `'modp15'`,
`'modp16'`, `'modp17'`, `'modp18'` (defined in [RFC 3526][]). The
returned object mimics the interface of objects created by
[`crypto.createDiffieHellman()`][], but will not allow changing
the keys (with [`diffieHellman.setPublicKey()`][], for example). The
advantage of using this method is that the parties do not have to
generate nor exchange a group modulus beforehand, saving both processor
and communication time.
Example (obtaining a shared secret):
```mjs
const {
getDiffieHellman
} = await import('crypto');
const alice = getDiffieHellman('modp14');
const bob = getDiffieHellman('modp14');
alice.generateKeys();
bob.generateKeys();
const aliceSecret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
const bobSecret = bob.computeSecret(alice.getPublicKey(), null, 'hex');
/* aliceSecret and bobSecret should be the same */
console.log(aliceSecret === bobSecret);
```
```cjs
const {
getDiffieHellman,
} = require('crypto');
const alice = getDiffieHellman('modp14');
const bob = getDiffieHellman('modp14');
alice.generateKeys();
bob.generateKeys();
const aliceSecret = alice.computeSecret(bob.getPublicKey(), null, 'hex');
const bobSecret = bob.computeSecret(alice.getPublicKey(), null, 'hex');
/* aliceSecret and bobSecret should be the same */
console.log(aliceSecret === bobSecret);
```
### `crypto.getFips()`
<!-- YAML
added: v10.0.0
-->
* Returns: {number} `1` if and only if a FIPS compliant crypto provider is
currently in use, `0` otherwise. A future semver-major release may change
the return type of this API to a {boolean}.
### `crypto.getHashes()`
<!-- YAML
added: v0.9.3
-->
* Returns: {string\[]} An array of the names of the supported hash algorithms,
such as `'RSA-SHA256'`. Hash algorithms are also called "digest" algorithms.
```mjs
const {
getHashes
} = await import('crypto');
console.log(getHashes()); // ['DSA', 'DSA-SHA', 'DSA-SHA1', ...]
```
```cjs
const {
getHashes,
} = require('crypto');
console.log(getHashes()); // ['DSA', 'DSA-SHA', 'DSA-SHA1', ...]
```
### `crypto.getRandomValues(typedArray)`
<!-- YAML
added: v17.4.0
-->
* `typedArray` {Buffer|TypedArray|DataView|ArrayBuffer}
* Returns: {Buffer|TypedArray|DataView|ArrayBuffer} Returns `typedArray`.
A convenient alias for [`crypto.webcrypto.getRandomValues()`][].
### `crypto.hkdf(digest, ikm, salt, info, keylen, callback)`
<!-- YAML
added: v15.0.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
-->
* `digest` {string} The digest algorithm to use.
* `ikm` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject} The input
keying material. It must be at least one byte in length.
* `salt` {string|ArrayBuffer|Buffer|TypedArray|DataView} The salt value. Must
be provided but can be zero-length.
* `info` {string|ArrayBuffer|Buffer|TypedArray|DataView} Additional info value.
Must be provided but can be zero-length, and cannot be more than 1024 bytes.
* `keylen` {number} The length of the key to generate. Must be greater than 0.
The maximum allowable value is `255` times the number of bytes produced by
the selected digest function (e.g. `sha512` generates 64-byte hashes, making
the maximum HKDF output 16320 bytes).
* `callback` {Function}
* `err` {Error}
* `derivedKey` {ArrayBuffer}
HKDF is a simple key derivation function defined in RFC 5869. The given `ikm`,
`salt` and `info` are used with the `digest` to derive a key of `keylen` bytes.
The supplied `callback` function is called with two arguments: `err` and
`derivedKey`. If an errors occurs while deriving the key, `err` will be set;
otherwise `err` will be `null`. The successfully generated `derivedKey` will
be passed to the callback as an {ArrayBuffer}. An error will be thrown if any
of the input arguments specify invalid values or types.
```mjs
import { Buffer } from 'buffer';
const {
hkdf
} = await import('crypto');
hkdf('sha512', 'key', 'salt', 'info', 64, (err, derivedKey) => {
if (err) throw err;
console.log(Buffer.from(derivedKey).toString('hex')); // '24156e2...5391653'
});
```
```cjs
const {
hkdf,
} = require('crypto');
const { Buffer } = require('buffer');
hkdf('sha512', 'key', 'salt', 'info', 64, (err, derivedKey) => {
if (err) throw err;
console.log(Buffer.from(derivedKey).toString('hex')); // '24156e2...5391653'
});
```
### `crypto.hkdfSync(digest, ikm, salt, info, keylen)`
<!-- YAML
added: v15.0.0
-->
* `digest` {string} The digest algorithm to use.
* `ikm` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject} The input
keying material. It must be at least one byte in length.
* `salt` {string|ArrayBuffer|Buffer|TypedArray|DataView} The salt value. Must
be provided but can be zero-length.
* `info` {string|ArrayBuffer|Buffer|TypedArray|DataView} Additional info value.
Must be provided but can be zero-length, and cannot be more than 1024 bytes.
* `keylen` {number} The length of the key to generate. Must be greater than 0.
The maximum allowable value is `255` times the number of bytes produced by
the selected digest function (e.g. `sha512` generates 64-byte hashes, making
the maximum HKDF output 16320 bytes).
* Returns: {ArrayBuffer}
Provides a synchronous HKDF key derivation function as defined in RFC 5869. The
given `ikm`, `salt` and `info` are used with the `digest` to derive a key of
`keylen` bytes.
The successfully generated `derivedKey` will be returned as an {ArrayBuffer}.
An error will be thrown if any of the input arguments specify invalid values or
types, or if the derived key cannot be generated.
```mjs
import { Buffer } from 'buffer';
const {
hkdfSync
} = await import('crypto');
const derivedKey = hkdfSync('sha512', 'key', 'salt', 'info', 64);
console.log(Buffer.from(derivedKey).toString('hex')); // '24156e2...5391653'
```
```cjs
const {
hkdfSync,
} = require('crypto');
const { Buffer } = require('buffer');
const derivedKey = hkdfSync('sha512', 'key', 'salt', 'info', 64);
console.log(Buffer.from(derivedKey).toString('hex')); // '24156e2...5391653'
```
### `crypto.pbkdf2(password, salt, iterations, keylen, digest, callback)`
<!-- YAML
added: v0.5.5
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The password and salt arguments can also be ArrayBuffer
instances.
- version: v14.0.0
pr-url: https://github.com/nodejs/node/pull/30578
description: The `iterations` parameter is now restricted to positive
values. Earlier releases treated other values as one.
- version: v8.0.0
pr-url: https://github.com/nodejs/node/pull/11305
description: The `digest` parameter is always required now.
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/4047
description: Calling this function without passing the `digest` parameter
is deprecated now and will emit a warning.
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default encoding for `password` if it is a string changed
from `binary` to `utf8`.
-->
* `password` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `salt` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `iterations` {number}
* `keylen` {number}
* `digest` {string}
* `callback` {Function}
* `err` {Error}
* `derivedKey` {Buffer}
Provides an asynchronous Password-Based Key Derivation Function 2 (PBKDF2)
implementation. A selected HMAC digest algorithm specified by `digest` is
applied to derive a key of the requested byte length (`keylen`) from the
`password`, `salt` and `iterations`.
The supplied `callback` function is called with two arguments: `err` and
`derivedKey`. If an error occurs while deriving the key, `err` will be set;
otherwise `err` will be `null`. By default, the successfully generated
`derivedKey` will be passed to the callback as a [`Buffer`][]. An error will be
thrown if any of the input arguments specify invalid values or types.
If `digest` is `null`, `'sha1'` will be used. This behavior is deprecated,
please specify a `digest` explicitly.
The `iterations` argument must be a number set as high as possible. The
higher the number of iterations, the more secure the derived key will be,
but will take a longer amount of time to complete.
The `salt` should be as unique as possible. It is recommended that a salt is
random and at least 16 bytes long. See [NIST SP 800-132][] for details.
When passing strings for `password` or `salt`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
```mjs
const {
pbkdf2
} = await import('crypto');
pbkdf2('secret', 'salt', 100000, 64, 'sha512', (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey.toString('hex')); // '3745e48...08d59ae'
});
```
```cjs
const {
pbkdf2,
} = require('crypto');
pbkdf2('secret', 'salt', 100000, 64, 'sha512', (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey.toString('hex')); // '3745e48...08d59ae'
});
```
The `crypto.DEFAULT_ENCODING` property can be used to change the way the
`derivedKey` is passed to the callback. This property, however, has been
deprecated and use should be avoided.
```mjs
import crypto from 'crypto';
crypto.DEFAULT_ENCODING = 'hex';
crypto.pbkdf2('secret', 'salt', 100000, 512, 'sha512', (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey); // '3745e48...aa39b34'
});
```
```cjs
const crypto = require('crypto');
crypto.DEFAULT_ENCODING = 'hex';
crypto.pbkdf2('secret', 'salt', 100000, 512, 'sha512', (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey); // '3745e48...aa39b34'
});
```
An array of supported digest functions can be retrieved using
[`crypto.getHashes()`][].
This API uses libuv's threadpool, which can have surprising and
negative performance implications for some applications; see the
[`UV_THREADPOOL_SIZE`][] documentation for more information.
### `crypto.pbkdf2Sync(password, salt, iterations, keylen, digest)`
<!-- YAML
added: v0.9.3
changes:
- version: v14.0.0
pr-url: https://github.com/nodejs/node/pull/30578
description: The `iterations` parameter is now restricted to positive
values. Earlier releases treated other values as one.
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/4047
description: Calling this function without passing the `digest` parameter
is deprecated now and will emit a warning.
- version: v6.0.0
pr-url: https://github.com/nodejs/node/pull/5522
description: The default encoding for `password` if it is a string changed
from `binary` to `utf8`.
-->
* `password` {string|Buffer|TypedArray|DataView}
* `salt` {string|Buffer|TypedArray|DataView}
* `iterations` {number}
* `keylen` {number}
* `digest` {string}
* Returns: {Buffer}
Provides a synchronous Password-Based Key Derivation Function 2 (PBKDF2)
implementation. A selected HMAC digest algorithm specified by `digest` is
applied to derive a key of the requested byte length (`keylen`) from the
`password`, `salt` and `iterations`.
If an error occurs an `Error` will be thrown, otherwise the derived key will be
returned as a [`Buffer`][].
If `digest` is `null`, `'sha1'` will be used. This behavior is deprecated,
please specify a `digest` explicitly.
The `iterations` argument must be a number set as high as possible. The
higher the number of iterations, the more secure the derived key will be,
but will take a longer amount of time to complete.
The `salt` should be as unique as possible. It is recommended that a salt is
random and at least 16 bytes long. See [NIST SP 800-132][] for details.
When passing strings for `password` or `salt`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
```mjs
const {
pbkdf2Sync
} = await import('crypto');
const key = pbkdf2Sync('secret', 'salt', 100000, 64, 'sha512');
console.log(key.toString('hex')); // '3745e48...08d59ae'
```
```cjs
const {
pbkdf2Sync,
} = require('crypto');
const key = pbkdf2Sync('secret', 'salt', 100000, 64, 'sha512');
console.log(key.toString('hex')); // '3745e48...08d59ae'
```
The `crypto.DEFAULT_ENCODING` property may be used to change the way the
`derivedKey` is returned. This property, however, is deprecated and use
should be avoided.
```mjs
import crypto from 'crypto';
crypto.DEFAULT_ENCODING = 'hex';
const key = crypto.pbkdf2Sync('secret', 'salt', 100000, 512, 'sha512');
console.log(key); // '3745e48...aa39b34'
```
```cjs
const crypto = require('crypto');
crypto.DEFAULT_ENCODING = 'hex';
const key = crypto.pbkdf2Sync('secret', 'salt', 100000, 512, 'sha512');
console.log(key); // '3745e48...aa39b34'
```
An array of supported digest functions can be retrieved using
[`crypto.getHashes()`][].
### `crypto.privateDecrypt(privateKey, buffer)`
<!-- YAML
added: v0.11.14
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: Added string, ArrayBuffer, and CryptoKey as allowable key
types. The oaepLabel can be an ArrayBuffer. The buffer can
be a string or ArrayBuffer. All types that accept buffers
are limited to a maximum of 2 ** 31 - 1 bytes.
- version: v12.11.0
pr-url: https://github.com/nodejs/node/pull/29489
description: The `oaepLabel` option was added.
- version: v12.9.0
pr-url: https://github.com/nodejs/node/pull/28335
description: The `oaepHash` option was added.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: This function now supports key objects.
-->
<!--lint disable maximum-line-length remark-lint-->
* `privateKey` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `oaepHash` {string} The hash function to use for OAEP padding and MGF1.
**Default:** `'sha1'`
* `oaepLabel` {string|ArrayBuffer|Buffer|TypedArray|DataView} The label to
use for OAEP padding. If not specified, no label is used.
* `padding` {crypto.constants} An optional padding value defined in
`crypto.constants`, which may be: `crypto.constants.RSA_NO_PADDING`,
`crypto.constants.RSA_PKCS1_PADDING`, or
`crypto.constants.RSA_PKCS1_OAEP_PADDING`.
* `buffer` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* Returns: {Buffer} A new `Buffer` with the decrypted content.
<!--lint enable maximum-line-length remark-lint-->
Decrypts `buffer` with `privateKey`. `buffer` was previously encrypted using
the corresponding public key, for example using [`crypto.publicEncrypt()`][].
If `privateKey` is not a [`KeyObject`][], this function behaves as if
`privateKey` had been passed to [`crypto.createPrivateKey()`][]. If it is an
object, the `padding` property can be passed. Otherwise, this function uses
`RSA_PKCS1_OAEP_PADDING`.
### `crypto.privateEncrypt(privateKey, buffer)`
<!-- YAML
added: v1.1.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: Added string, ArrayBuffer, and CryptoKey as allowable key
types. The passphrase can be an ArrayBuffer. The buffer can
be a string or ArrayBuffer. All types that accept buffers
are limited to a maximum of 2 ** 31 - 1 bytes.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: This function now supports key objects.
-->
<!--lint disable maximum-line-length remark-lint-->
* `privateKey` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
A PEM encoded private key.
* `passphrase` {string|ArrayBuffer|Buffer|TypedArray|DataView} An optional
passphrase for the private key.
* `padding` {crypto.constants} An optional padding value defined in
`crypto.constants`, which may be: `crypto.constants.RSA_NO_PADDING` or
`crypto.constants.RSA_PKCS1_PADDING`.
* `encoding` {string} The string encoding to use when `buffer`, `key`,
or `passphrase` are strings.
* `buffer` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* Returns: {Buffer} A new `Buffer` with the encrypted content.
<!--lint enable maximum-line-length remark-lint-->
Encrypts `buffer` with `privateKey`. The returned data can be decrypted using
the corresponding public key, for example using [`crypto.publicDecrypt()`][].
If `privateKey` is not a [`KeyObject`][], this function behaves as if
`privateKey` had been passed to [`crypto.createPrivateKey()`][]. If it is an
object, the `padding` property can be passed. Otherwise, this function uses
`RSA_PKCS1_PADDING`.
### `crypto.publicDecrypt(key, buffer)`
<!-- YAML
added: v1.1.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: Added string, ArrayBuffer, and CryptoKey as allowable key
types. The passphrase can be an ArrayBuffer. The buffer can
be a string or ArrayBuffer. All types that accept buffers
are limited to a maximum of 2 ** 31 - 1 bytes.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: This function now supports key objects.
-->
<!--lint disable maximum-line-length remark-lint-->
* `key` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `passphrase` {string|ArrayBuffer|Buffer|TypedArray|DataView} An optional
passphrase for the private key.
* `padding` {crypto.constants} An optional padding value defined in
`crypto.constants`, which may be: `crypto.constants.RSA_NO_PADDING` or
`crypto.constants.RSA_PKCS1_PADDING`.
* `encoding` {string} The string encoding to use when `buffer`, `key`,
or `passphrase` are strings.
* `buffer` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* Returns: {Buffer} A new `Buffer` with the decrypted content.
<!--lint enable maximum-line-length remark-lint-->
Decrypts `buffer` with `key`.`buffer` was previously encrypted using
the corresponding private key, for example using [`crypto.privateEncrypt()`][].
If `key` is not a [`KeyObject`][], this function behaves as if
`key` had been passed to [`crypto.createPublicKey()`][]. If it is an
object, the `padding` property can be passed. Otherwise, this function uses
`RSA_PKCS1_PADDING`.
Because RSA public keys can be derived from private keys, a private key may
be passed instead of a public key.
### `crypto.publicEncrypt(key, buffer)`
<!-- YAML
added: v0.11.14
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: Added string, ArrayBuffer, and CryptoKey as allowable key
types. The oaepLabel and passphrase can be ArrayBuffers. The
buffer can be a string or ArrayBuffer. All types that accept
buffers are limited to a maximum of 2 ** 31 - 1 bytes.
- version: v12.11.0
pr-url: https://github.com/nodejs/node/pull/29489
description: The `oaepLabel` option was added.
- version: v12.9.0
pr-url: https://github.com/nodejs/node/pull/28335
description: The `oaepHash` option was added.
- version: v11.6.0
pr-url: https://github.com/nodejs/node/pull/24234
description: This function now supports key objects.
-->
<!--lint disable maximum-line-length remark-lint-->
* `key` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `key` {string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
A PEM encoded public or private key, {KeyObject}, or {CryptoKey}.
* `oaepHash` {string} The hash function to use for OAEP padding and MGF1.
**Default:** `'sha1'`
* `oaepLabel` {string|ArrayBuffer|Buffer|TypedArray|DataView} The label to
use for OAEP padding. If not specified, no label is used.
* `passphrase` {string|ArrayBuffer|Buffer|TypedArray|DataView} An optional
passphrase for the private key.
* `padding` {crypto.constants} An optional padding value defined in
`crypto.constants`, which may be: `crypto.constants.RSA_NO_PADDING`,
`crypto.constants.RSA_PKCS1_PADDING`, or
`crypto.constants.RSA_PKCS1_OAEP_PADDING`.
* `encoding` {string} The string encoding to use when `buffer`, `key`,
`oaepLabel`, or `passphrase` are strings.
* `buffer` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* Returns: {Buffer} A new `Buffer` with the encrypted content.
<!--lint enable maximum-line-length remark-lint-->
Encrypts the content of `buffer` with `key` and returns a new
[`Buffer`][] with encrypted content. The returned data can be decrypted using
the corresponding private key, for example using [`crypto.privateDecrypt()`][].
If `key` is not a [`KeyObject`][], this function behaves as if
`key` had been passed to [`crypto.createPublicKey()`][]. If it is an
object, the `padding` property can be passed. Otherwise, this function uses
`RSA_PKCS1_OAEP_PADDING`.
Because RSA public keys can be derived from private keys, a private key may
be passed instead of a public key.
### `crypto.randomBytes(size[, callback])`
<!-- YAML
added: v0.5.8
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v9.0.0
pr-url: https://github.com/nodejs/node/pull/16454
description: Passing `null` as the `callback` argument now throws
`ERR_INVALID_CALLBACK`.
-->
* `size` {number} The number of bytes to generate. The `size` must
not be larger than `2**31 - 1`.
* `callback` {Function}
* `err` {Error}
* `buf` {Buffer}
* Returns: {Buffer} if the `callback` function is not provided.
Generates cryptographically strong pseudorandom data. The `size` argument
is a number indicating the number of bytes to generate.
If a `callback` function is provided, the bytes are generated asynchronously
and the `callback` function is invoked with two arguments: `err` and `buf`.
If an error occurs, `err` will be an `Error` object; otherwise it is `null`. The
`buf` argument is a [`Buffer`][] containing the generated bytes.
```mjs
// Asynchronous
const {
randomBytes
} = await import('crypto');
randomBytes(256, (err, buf) => {
if (err) throw err;
console.log(`${buf.length} bytes of random data: ${buf.toString('hex')}`);
});
```
```cjs
// Asynchronous
const {
randomBytes,
} = require('crypto');
randomBytes(256, (err, buf) => {
if (err) throw err;
console.log(`${buf.length} bytes of random data: ${buf.toString('hex')}`);
});
```
If the `callback` function is not provided, the random bytes are generated
synchronously and returned as a [`Buffer`][]. An error will be thrown if
there is a problem generating the bytes.
```mjs
// Synchronous
const {
randomBytes
} = await import('crypto');
const buf = randomBytes(256);
console.log(
`${buf.length} bytes of random data: ${buf.toString('hex')}`);
```
```cjs
// Synchronous
const {
randomBytes,
} = require('crypto');
const buf = randomBytes(256);
console.log(
`${buf.length} bytes of random data: ${buf.toString('hex')}`);
```
The `crypto.randomBytes()` method will not complete until there is
sufficient entropy available.
This should normally never take longer than a few milliseconds. The only time
when generating the random bytes may conceivably block for a longer period of
time is right after boot, when the whole system is still low on entropy.
This API uses libuv's threadpool, which can have surprising and
negative performance implications for some applications; see the
[`UV_THREADPOOL_SIZE`][] documentation for more information.
The asynchronous version of `crypto.randomBytes()` is carried out in a single
threadpool request. To minimize threadpool task length variation, partition
large `randomBytes` requests when doing so as part of fulfilling a client
request.
### `crypto.randomFillSync(buffer[, offset][, size])`
<!-- YAML
added:
- v7.10.0
- v6.13.0
changes:
- version: v9.0.0
pr-url: https://github.com/nodejs/node/pull/15231
description: The `buffer` argument may be any `TypedArray` or `DataView`.
-->
* `buffer` {ArrayBuffer|Buffer|TypedArray|DataView} Must be supplied. The
size of the provided `buffer` must not be larger than `2**31 - 1`.
* `offset` {number} **Default:** `0`
* `size` {number} **Default:** `buffer.length - offset`. The `size` must
not be larger than `2**31 - 1`.
* Returns: {ArrayBuffer|Buffer|TypedArray|DataView} The object passed as
`buffer` argument.
Synchronous version of [`crypto.randomFill()`][].
```mjs
import { Buffer } from 'buffer';
const { randomFillSync } = await import('crypto');
const buf = Buffer.alloc(10);
console.log(randomFillSync(buf).toString('hex'));
randomFillSync(buf, 5);
console.log(buf.toString('hex'));
// The above is equivalent to the following:
randomFillSync(buf, 5, 5);
console.log(buf.toString('hex'));
```
```cjs
const { randomFillSync } = require('crypto');
const { Buffer } = require('buffer');
const buf = Buffer.alloc(10);
console.log(randomFillSync(buf).toString('hex'));
randomFillSync(buf, 5);
console.log(buf.toString('hex'));
// The above is equivalent to the following:
randomFillSync(buf, 5, 5);
console.log(buf.toString('hex'));
```
Any `ArrayBuffer`, `TypedArray` or `DataView` instance may be passed as
`buffer`.
```mjs
import { Buffer } from 'buffer';
const { randomFillSync } = await import('crypto');
const a = new Uint32Array(10);
console.log(Buffer.from(randomFillSync(a).buffer,
a.byteOffset, a.byteLength).toString('hex'));
const b = new DataView(new ArrayBuffer(10));
console.log(Buffer.from(randomFillSync(b).buffer,
b.byteOffset, b.byteLength).toString('hex'));
const c = new ArrayBuffer(10);
console.log(Buffer.from(randomFillSync(c)).toString('hex'));
```
```cjs
const { randomFillSync } = require('crypto');
const { Buffer } = require('buffer');
const a = new Uint32Array(10);
console.log(Buffer.from(randomFillSync(a).buffer,
a.byteOffset, a.byteLength).toString('hex'));
const b = new DataView(new ArrayBuffer(10));
console.log(Buffer.from(randomFillSync(b).buffer,
b.byteOffset, b.byteLength).toString('hex'));
const c = new ArrayBuffer(10);
console.log(Buffer.from(randomFillSync(c)).toString('hex'));
```
### `crypto.randomFill(buffer[, offset][, size], callback)`
<!-- YAML
added:
- v7.10.0
- v6.13.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v9.0.0
pr-url: https://github.com/nodejs/node/pull/15231
description: The `buffer` argument may be any `TypedArray` or `DataView`.
-->
* `buffer` {ArrayBuffer|Buffer|TypedArray|DataView} Must be supplied. The
size of the provided `buffer` must not be larger than `2**31 - 1`.
* `offset` {number} **Default:** `0`
* `size` {number} **Default:** `buffer.length - offset`. The `size` must
not be larger than `2**31 - 1`.
* `callback` {Function} `function(err, buf) {}`.
This function is similar to [`crypto.randomBytes()`][] but requires the first
argument to be a [`Buffer`][] that will be filled. It also
requires that a callback is passed in.
If the `callback` function is not provided, an error will be thrown.
```mjs
import { Buffer } from 'buffer';
const { randomFill } = await import('crypto');
const buf = Buffer.alloc(10);
randomFill(buf, (err, buf) => {
if (err) throw err;
console.log(buf.toString('hex'));
});
randomFill(buf, 5, (err, buf) => {
if (err) throw err;
console.log(buf.toString('hex'));
});
// The above is equivalent to the following:
randomFill(buf, 5, 5, (err, buf) => {
if (err) throw err;
console.log(buf.toString('hex'));
});
```
```cjs
const { randomFill } = require('crypto');
const { Buffer } = require('buffer');
const buf = Buffer.alloc(10);
randomFill(buf, (err, buf) => {
if (err) throw err;
console.log(buf.toString('hex'));
});
randomFill(buf, 5, (err, buf) => {
if (err) throw err;
console.log(buf.toString('hex'));
});
// The above is equivalent to the following:
randomFill(buf, 5, 5, (err, buf) => {
if (err) throw err;
console.log(buf.toString('hex'));
});
```
Any `ArrayBuffer`, `TypedArray`, or `DataView` instance may be passed as
`buffer`.
While this includes instances of `Float32Array` and `Float64Array`, this
function should not be used to generate random floating-point numbers. The
result may contain `+Infinity`, `-Infinity`, and `NaN`, and even if the array
contains finite numbers only, they are not drawn from a uniform random
distribution and have no meaningful lower or upper bounds.
```mjs
import { Buffer } from 'buffer';
const { randomFill } = await import('crypto');
const a = new Uint32Array(10);
randomFill(a, (err, buf) => {
if (err) throw err;
console.log(Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength)
.toString('hex'));
});
const b = new DataView(new ArrayBuffer(10));
randomFill(b, (err, buf) => {
if (err) throw err;
console.log(Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength)
.toString('hex'));
});
const c = new ArrayBuffer(10);
randomFill(c, (err, buf) => {
if (err) throw err;
console.log(Buffer.from(buf).toString('hex'));
});
```
```cjs
const { randomFill } = require('crypto');
const { Buffer } = require('buffer');
const a = new Uint32Array(10);
randomFill(a, (err, buf) => {
if (err) throw err;
console.log(Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength)
.toString('hex'));
});
const b = new DataView(new ArrayBuffer(10));
randomFill(b, (err, buf) => {
if (err) throw err;
console.log(Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength)
.toString('hex'));
});
const c = new ArrayBuffer(10);
randomFill(c, (err, buf) => {
if (err) throw err;
console.log(Buffer.from(buf).toString('hex'));
});
```
This API uses libuv's threadpool, which can have surprising and
negative performance implications for some applications; see the
[`UV_THREADPOOL_SIZE`][] documentation for more information.
The asynchronous version of `crypto.randomFill()` is carried out in a single
threadpool request. To minimize threadpool task length variation, partition
large `randomFill` requests when doing so as part of fulfilling a client
request.
### `crypto.randomInt([min, ]max[, callback])`
<!-- YAML
added:
- v14.10.0
- v12.19.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
-->
* `min` {integer} Start of random range (inclusive). **Default:** `0`.
* `max` {integer} End of random range (exclusive).
* `callback` {Function} `function(err, n) {}`.
Return a random integer `n` such that `min <= n < max`. This
implementation avoids [modulo bias][].
The range (`max - min`) must be less than 2<sup>48</sup>. `min` and `max` must
be [safe integers][].
If the `callback` function is not provided, the random integer is
generated synchronously.
```mjs
// Asynchronous
const {
randomInt
} = await import('crypto');
randomInt(3, (err, n) => {
if (err) throw err;
console.log(`Random number chosen from (0, 1, 2): ${n}`);
});
```
```cjs
// Asynchronous
const {
randomInt,
} = require('crypto');
randomInt(3, (err, n) => {
if (err) throw err;
console.log(`Random number chosen from (0, 1, 2): ${n}`);
});
```
```mjs
// Synchronous
const {
randomInt
} = await import('crypto');
const n = randomInt(3);
console.log(`Random number chosen from (0, 1, 2): ${n}`);
```
```cjs
// Synchronous
const {
randomInt,
} = require('crypto');
const n = randomInt(3);
console.log(`Random number chosen from (0, 1, 2): ${n}`);
```
```mjs
// With `min` argument
const {
randomInt
} = await import('crypto');
const n = randomInt(1, 7);
console.log(`The dice rolled: ${n}`);
```
```cjs
// With `min` argument
const {
randomInt,
} = require('crypto');
const n = randomInt(1, 7);
console.log(`The dice rolled: ${n}`);
```
### `crypto.randomUUID([options])`
<!-- YAML
added:
- v15.6.0
- v14.17.0
-->
* `options` {Object}
* `disableEntropyCache` {boolean} By default, to improve performance,
Node.js generates and caches enough
random data to generate up to 128 random UUIDs. To generate a UUID
without using the cache, set `disableEntropyCache` to `true`.
**Default:** `false`.
* Returns: {string}
Generates a random [RFC 4122][] version 4 UUID. The UUID is generated using a
cryptographic pseudorandom number generator.
### `crypto.scrypt(password, salt, keylen[, options], callback)`
<!-- YAML
added: v10.5.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The password and salt arguments can also be ArrayBuffer
instances.
- version:
- v12.8.0
- v10.17.0
pr-url: https://github.com/nodejs/node/pull/28799
description: The `maxmem` value can now be any safe integer.
- version: v10.9.0
pr-url: https://github.com/nodejs/node/pull/21525
description: The `cost`, `blockSize` and `parallelization` option names
have been added.
-->
* `password` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `salt` {string|ArrayBuffer|Buffer|TypedArray|DataView}
* `keylen` {number}
* `options` {Object}
* `cost` {number} CPU/memory cost parameter. Must be a power of two greater
than one. **Default:** `16384`.
* `blockSize` {number} Block size parameter. **Default:** `8`.
* `parallelization` {number} Parallelization parameter. **Default:** `1`.
* `N` {number} Alias for `cost`. Only one of both may be specified.
* `r` {number} Alias for `blockSize`. Only one of both may be specified.
* `p` {number} Alias for `parallelization`. Only one of both may be specified.
* `maxmem` {number} Memory upper bound. It is an error when (approximately)
`128 * N * r > maxmem`. **Default:** `32 * 1024 * 1024`.
* `callback` {Function}
* `err` {Error}
* `derivedKey` {Buffer}
Provides an asynchronous [scrypt][] implementation. Scrypt is a password-based
key derivation function that is designed to be expensive computationally and
memory-wise in order to make brute-force attacks unrewarding.
The `salt` should be as unique as possible. It is recommended that a salt is
random and at least 16 bytes long. See [NIST SP 800-132][] for details.
When passing strings for `password` or `salt`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
The `callback` function is called with two arguments: `err` and `derivedKey`.
`err` is an exception object when key derivation fails, otherwise `err` is
`null`. `derivedKey` is passed to the callback as a [`Buffer`][].
An exception is thrown when any of the input arguments specify invalid values
or types.
```mjs
const {
scrypt
} = await import('crypto');
// Using the factory defaults.
scrypt('password', 'salt', 64, (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey.toString('hex')); // '3745e48...08d59ae'
});
// Using a custom N parameter. Must be a power of two.
scrypt('password', 'salt', 64, { N: 1024 }, (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey.toString('hex')); // '3745e48...aa39b34'
});
```
```cjs
const {
scrypt,
} = require('crypto');
// Using the factory defaults.
scrypt('password', 'salt', 64, (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey.toString('hex')); // '3745e48...08d59ae'
});
// Using a custom N parameter. Must be a power of two.
scrypt('password', 'salt', 64, { N: 1024 }, (err, derivedKey) => {
if (err) throw err;
console.log(derivedKey.toString('hex')); // '3745e48...aa39b34'
});
```
### `crypto.scryptSync(password, salt, keylen[, options])`
<!-- YAML
added: v10.5.0
changes:
- version:
- v12.8.0
- v10.17.0
pr-url: https://github.com/nodejs/node/pull/28799
description: The `maxmem` value can now be any safe integer.
- version: v10.9.0
pr-url: https://github.com/nodejs/node/pull/21525
description: The `cost`, `blockSize` and `parallelization` option names
have been added.
-->
* `password` {string|Buffer|TypedArray|DataView}
* `salt` {string|Buffer|TypedArray|DataView}
* `keylen` {number}
* `options` {Object}
* `cost` {number} CPU/memory cost parameter. Must be a power of two greater
than one. **Default:** `16384`.
* `blockSize` {number} Block size parameter. **Default:** `8`.
* `parallelization` {number} Parallelization parameter. **Default:** `1`.
* `N` {number} Alias for `cost`. Only one of both may be specified.
* `r` {number} Alias for `blockSize`. Only one of both may be specified.
* `p` {number} Alias for `parallelization`. Only one of both may be specified.
* `maxmem` {number} Memory upper bound. It is an error when (approximately)
`128 * N * r > maxmem`. **Default:** `32 * 1024 * 1024`.
* Returns: {Buffer}
Provides a synchronous [scrypt][] implementation. Scrypt is a password-based
key derivation function that is designed to be expensive computationally and
memory-wise in order to make brute-force attacks unrewarding.
The `salt` should be as unique as possible. It is recommended that a salt is
random and at least 16 bytes long. See [NIST SP 800-132][] for details.
When passing strings for `password` or `salt`, please consider
[caveats when using strings as inputs to cryptographic APIs][].
An exception is thrown when key derivation fails, otherwise the derived key is
returned as a [`Buffer`][].
An exception is thrown when any of the input arguments specify invalid values
or types.
```mjs
const {
scryptSync
} = await import('crypto');
// Using the factory defaults.
const key1 = scryptSync('password', 'salt', 64);
console.log(key1.toString('hex')); // '3745e48...08d59ae'
// Using a custom N parameter. Must be a power of two.
const key2 = scryptSync('password', 'salt', 64, { N: 1024 });
console.log(key2.toString('hex')); // '3745e48...aa39b34'
```
```cjs
const {
scryptSync,
} = require('crypto');
// Using the factory defaults.
const key1 = scryptSync('password', 'salt', 64);
console.log(key1.toString('hex')); // '3745e48...08d59ae'
// Using a custom N parameter. Must be a power of two.
const key2 = scryptSync('password', 'salt', 64, { N: 1024 });
console.log(key2.toString('hex')); // '3745e48...aa39b34'
```
### `crypto.secureHeapUsed()`
<!-- YAML
added: v15.6.0
-->
* Returns: {Object}
* `total` {number} The total allocated secure heap size as specified
using the `--secure-heap=n` command-line flag.
* `min` {number} The minimum allocation from the secure heap as
specified using the `--secure-heap-min` command-line flag.
* `used` {number} The total number of bytes currently allocated from
the secure heap.
* `utilization` {number} The calculated ratio of `used` to `total`
allocated bytes.
### `crypto.setEngine(engine[, flags])`
<!-- YAML
added: v0.11.11
-->
* `engine` {string}
* `flags` {crypto.constants} **Default:** `crypto.constants.ENGINE_METHOD_ALL`
Load and set the `engine` for some or all OpenSSL functions (selected by flags).
`engine` could be either an id or a path to the engine's shared library.
The optional `flags` argument uses `ENGINE_METHOD_ALL` by default. The `flags`
is a bit field taking one of or a mix of the following flags (defined in
`crypto.constants`):
* `crypto.constants.ENGINE_METHOD_RSA`
* `crypto.constants.ENGINE_METHOD_DSA`
* `crypto.constants.ENGINE_METHOD_DH`
* `crypto.constants.ENGINE_METHOD_RAND`
* `crypto.constants.ENGINE_METHOD_EC`
* `crypto.constants.ENGINE_METHOD_CIPHERS`
* `crypto.constants.ENGINE_METHOD_DIGESTS`
* `crypto.constants.ENGINE_METHOD_PKEY_METHS`
* `crypto.constants.ENGINE_METHOD_PKEY_ASN1_METHS`
* `crypto.constants.ENGINE_METHOD_ALL`
* `crypto.constants.ENGINE_METHOD_NONE`
The flags below are deprecated in OpenSSL-1.1.0.
* `crypto.constants.ENGINE_METHOD_ECDH`
* `crypto.constants.ENGINE_METHOD_ECDSA`
* `crypto.constants.ENGINE_METHOD_STORE`
### `crypto.setFips(bool)`
<!-- YAML
added: v10.0.0
-->
* `bool` {boolean} `true` to enable FIPS mode.
Enables the FIPS compliant crypto provider in a FIPS-enabled Node.js build.
Throws an error if FIPS mode is not available.
### `crypto.sign(algorithm, data, key[, callback])`
<!-- YAML
added: v12.0.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v15.12.0
pr-url: https://github.com/nodejs/node/pull/37500
description: Optional callback argument added.
- version:
- v13.2.0
- v12.16.0
pr-url: https://github.com/nodejs/node/pull/29292
description: This function now supports IEEE-P1363 DSA and ECDSA signatures.
-->
<!--lint disable maximum-line-length remark-lint-->
* `algorithm` {string | null | undefined}
* `data` {ArrayBuffer|Buffer|TypedArray|DataView}
* `key` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `callback` {Function}
* `err` {Error}
* `signature` {Buffer}
* Returns: {Buffer} if the `callback` function is not provided.
<!--lint enable maximum-line-length remark-lint-->
Calculates and returns the signature for `data` using the given private key and
algorithm. If `algorithm` is `null` or `undefined`, then the algorithm is
dependent upon the key type (especially Ed25519 and Ed448).
If `key` is not a [`KeyObject`][], this function behaves as if `key` had been
passed to [`crypto.createPrivateKey()`][]. If it is an object, the following
additional properties can be passed:
* `dsaEncoding` {string} For DSA and ECDSA, this option specifies the
format of the generated signature. It can be one of the following:
* `'der'` (default): DER-encoded ASN.1 signature structure encoding `(r, s)`.
* `'ieee-p1363'`: Signature format `r || s` as proposed in IEEE-P1363.
* `padding` {integer} Optional padding value for RSA, one of the following:
* `crypto.constants.RSA_PKCS1_PADDING` (default)
* `crypto.constants.RSA_PKCS1_PSS_PADDING`
`RSA_PKCS1_PSS_PADDING` will use MGF1 with the same hash function
used to sign the message as specified in section 3.1 of [RFC 4055][].
* `saltLength` {integer} Salt length for when padding is
`RSA_PKCS1_PSS_PADDING`. The special value
`crypto.constants.RSA_PSS_SALTLEN_DIGEST` sets the salt length to the digest
size, `crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN` (default) sets it to the
maximum permissible value.
If the `callback` function is provided this function uses libuv's threadpool.
### `crypto.subtle`
<!-- YAML
added: v17.4.0
-->
* Type: {SubtleCrypto}
A convenient alias for [`crypto.webcrypto.subtle`][].
### `crypto.timingSafeEqual(a, b)`
<!-- YAML
added: v6.6.0
changes:
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The a and b arguments can also be ArrayBuffer.
-->
* `a` {ArrayBuffer|Buffer|TypedArray|DataView}
* `b` {ArrayBuffer|Buffer|TypedArray|DataView}
* Returns: {boolean}
This function is based on a constant-time algorithm.
Returns true if `a` is equal to `b`, without leaking timing information that
would allow an attacker to guess one of the values. This is suitable for
comparing HMAC digests or secret values like authentication cookies or
[capability urls](https://www.w3.org/TR/capability-urls/).
`a` and `b` must both be `Buffer`s, `TypedArray`s, or `DataView`s, and they
must have the same byte length. An error is thrown if `a` and `b` have
different byte lengths.
If at least one of `a` and `b` is a `TypedArray` with more than one byte per
entry, such as `Uint16Array`, the result will be computed using the platform
byte order.
Use of `crypto.timingSafeEqual` does not guarantee that the _surrounding_ code
is timing-safe. Care should be taken to ensure that the surrounding code does
not introduce timing vulnerabilities.
### `crypto.verify(algorithm, data, key, signature[, callback])`
<!-- YAML
added: v12.0.0
changes:
- version: REPLACEME
pr-url: https://github.com/nodejs/node/pull/41678
description: Passing an invalid callback to the `callback` argument
now throws `ERR_INVALID_ARG_TYPE` instead of
`ERR_INVALID_CALLBACK`.
- version: v15.12.0
pr-url: https://github.com/nodejs/node/pull/37500
description: Optional callback argument added.
- version: v15.0.0
pr-url: https://github.com/nodejs/node/pull/35093
description: The data, key, and signature arguments can also be ArrayBuffer.
- version:
- v13.2.0
- v12.16.0
pr-url: https://github.com/nodejs/node/pull/29292
description: This function now supports IEEE-P1363 DSA and ECDSA signatures.
-->
<!--lint disable maximum-line-length remark-lint-->
* `algorithm` {string|null|undefined}
* `data` {ArrayBuffer| Buffer|TypedArray|DataView}
* `key` {Object|string|ArrayBuffer|Buffer|TypedArray|DataView|KeyObject|CryptoKey}
* `signature` {ArrayBuffer|Buffer|TypedArray|DataView}
* `callback` {Function}
* `err` {Error}
* `result` {boolean}
* Returns: {boolean} `true` or `false` depending on the validity of the
signature for the data and public key if the `callback` function is not
provided.
<!--lint enable maximum-line-length remark-lint-->
Verifies the given signature for `data` using the given key and algorithm. If
`algorithm` is `null` or `undefined`, then the algorithm is dependent upon the
key type (especially Ed25519 and Ed448).
If `key` is not a [`KeyObject`][], this function behaves as if `key` had been
passed to [`crypto.createPublicKey()`][]. If it is an object, the following
additional properties can be passed:
* `dsaEncoding` {string} For DSA and ECDSA, this option specifies the
format of the signature. It can be one of the following:
* `'der'` (default): DER-encoded ASN.1 signature structure encoding `(r, s)`.
* `'ieee-p1363'`: Signature format `r || s` as proposed in IEEE-P1363.
* `padding` {integer} Optional padding value for RSA, one of the following:
* `crypto.constants.RSA_PKCS1_PADDING` (default)
* `crypto.constants.RSA_PKCS1_PSS_PADDING`
`RSA_PKCS1_PSS_PADDING` will use MGF1 with the same hash function
used to sign the message as specified in section 3.1 of [RFC 4055][].
* `saltLength` {integer} Salt length for when padding is
`RSA_PKCS1_PSS_PADDING`. The special value
`crypto.constants.RSA_PSS_SALTLEN_DIGEST` sets the salt length to the digest
size, `crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN` (default) sets it to the
maximum permissible value.
The `signature` argument is the previously calculated signature for the `data`.
Because public keys can be derived from private keys, a private key or a public
key may be passed for `key`.
If the `callback` function is provided this function uses libuv's threadpool.
### `crypto.webcrypto`
<!-- YAML
added: v15.0.0
-->
Type: {Crypto} An implementation of the Web Crypto API standard.
See the [Web Crypto API documentation][] for details.
## Notes
### Using strings as inputs to cryptographic APIs
For historical reasons, many cryptographic APIs provided by Node.js accept
strings as inputs where the underlying cryptographic algorithm works on byte
sequences. These instances include plaintexts, ciphertexts, symmetric keys,
initialization vectors, passphrases, salts, authentication tags,
and additional authenticated data.
When passing strings to cryptographic APIs, consider the following factors.
* Not all byte sequences are valid UTF-8 strings. Therefore, when a byte
sequence of length `n` is derived from a string, its entropy is generally
lower than the entropy of a random or pseudorandom `n` byte sequence.
For example, no UTF-8 string will result in the byte sequence `c0 af`. Secret
keys should almost exclusively be random or pseudorandom byte sequences.
* Similarly, when converting random or pseudorandom byte sequences to UTF-8
strings, subsequences that do not represent valid code points may be replaced
by the Unicode replacement character (`U+FFFD`). The byte representation of
the resulting Unicode string may, therefore, not be equal to the byte sequence
that the string was created from.
```js
const original = [0xc0, 0xaf];
const bytesAsString = Buffer.from(original).toString('utf8');
const stringAsBytes = Buffer.from(bytesAsString, 'utf8');
console.log(stringAsBytes);
// Prints '<Buffer ef bf bd ef bf bd>'.
```
The outputs of ciphers, hash functions, signature algorithms, and key
derivation functions are pseudorandom byte sequences and should not be
used as Unicode strings.
* When strings are obtained from user input, some Unicode characters can be
represented in multiple equivalent ways that result in different byte
sequences. For example, when passing a user passphrase to a key derivation
function, such as PBKDF2 or scrypt, the result of the key derivation function
depends on whether the string uses composed or decomposed characters. Node.js
does not normalize character representations. Developers should consider using
[`String.prototype.normalize()`][] on user inputs before passing them to
cryptographic APIs.
### Legacy streams API (prior to Node.js 0.10)
The Crypto module was added to Node.js before there was the concept of a
unified Stream API, and before there were [`Buffer`][] objects for handling
binary data. As such, the many of the `crypto` defined classes have methods not
typically found on other Node.js classes that implement the [streams][stream]
API (e.g. `update()`, `final()`, or `digest()`). Also, many methods accepted
and returned `'latin1'` encoded strings by default rather than `Buffer`s. This
default was changed after Node.js v0.8 to use [`Buffer`][] objects by default
instead.
### Support for weak or compromised algorithms
The `crypto` module still supports some algorithms which are already
compromised and are not currently recommended for use. The API also allows
the use of ciphers and hashes with a small key size that are too weak for safe
use.
Users should take full responsibility for selecting the crypto
algorithm and key size according to their security requirements.
Based on the recommendations of [NIST SP 800-131A][]:
* MD5 and SHA-1 are no longer acceptable where collision resistance is
required such as digital signatures.
* The key used with RSA, DSA, and DH algorithms is recommended to have
at least 2048 bits and that of the curve of ECDSA and ECDH at least
224 bits, to be safe to use for several years.
* The DH groups of `modp1`, `modp2` and `modp5` have a key size
smaller than 2048 bits and are not recommended.
See the reference for other recommendations and details.
Some algorithms that have known weaknesses and are of little relevance in
practice are only available through the [legacy provider][], which is not
enabled by default.
### CCM mode
CCM is one of the supported [AEAD algorithms][]. Applications which use this
mode must adhere to certain restrictions when using the cipher API:
* The authentication tag length must be specified during cipher creation by
setting the `authTagLength` option and must be one of 4, 6, 8, 10, 12, 14 or
16 bytes.
* The length of the initialization vector (nonce) `N` must be between 7 and 13
bytes (`7 ≤ N ≤ 13`).
* The length of the plaintext is limited to `2 ** (8 * (15 - N))` bytes.
* When decrypting, the authentication tag must be set via `setAuthTag()` before
calling `update()`.
Otherwise, decryption will fail and `final()` will throw an error in
compliance with section 2.6 of [RFC 3610][].
* Using stream methods such as `write(data)`, `end(data)` or `pipe()` in CCM
mode might fail as CCM cannot handle more than one chunk of data per instance.
* When passing additional authenticated data (AAD), the length of the actual
message in bytes must be passed to `setAAD()` via the `plaintextLength`
option.
Many crypto libraries include the authentication tag in the ciphertext,
which means that they produce ciphertexts of the length
`plaintextLength + authTagLength`. Node.js does not include the authentication
tag, so the ciphertext length is always `plaintextLength`.
This is not necessary if no AAD is used.
* As CCM processes the whole message at once, `update()` must be called exactly
once.
* Even though calling `update()` is sufficient to encrypt/decrypt the message,
applications _must_ call `final()` to compute or verify the
authentication tag.
```mjs
import { Buffer } from 'buffer';
const {
createCipheriv,
createDecipheriv,
randomBytes
} = await import('crypto');
const key = 'keykeykeykeykeykeykeykey';
const nonce = randomBytes(12);
const aad = Buffer.from('0123456789', 'hex');
const cipher = createCipheriv('aes-192-ccm', key, nonce, {
authTagLength: 16
});
const plaintext = 'Hello world';
cipher.setAAD(aad, {
plaintextLength: Buffer.byteLength(plaintext)
});
const ciphertext = cipher.update(plaintext, 'utf8');
cipher.final();
const tag = cipher.getAuthTag();
// Now transmit { ciphertext, nonce, tag }.
const decipher = createDecipheriv('aes-192-ccm', key, nonce, {
authTagLength: 16
});
decipher.setAuthTag(tag);
decipher.setAAD(aad, {
plaintextLength: ciphertext.length
});
const receivedPlaintext = decipher.update(ciphertext, null, 'utf8');
try {
decipher.final();
} catch (err) {
throw new Error('Authentication failed!', { cause: err });
}
console.log(receivedPlaintext);
```
```cjs
const {
createCipheriv,
createDecipheriv,
randomBytes,
} = require('crypto');
const { Buffer } = require('buffer');
const key = 'keykeykeykeykeykeykeykey';
const nonce = randomBytes(12);
const aad = Buffer.from('0123456789', 'hex');
const cipher = createCipheriv('aes-192-ccm', key, nonce, {
authTagLength: 16
});
const plaintext = 'Hello world';
cipher.setAAD(aad, {
plaintextLength: Buffer.byteLength(plaintext)
});
const ciphertext = cipher.update(plaintext, 'utf8');
cipher.final();
const tag = cipher.getAuthTag();
// Now transmit { ciphertext, nonce, tag }.
const decipher = createDecipheriv('aes-192-ccm', key, nonce, {
authTagLength: 16
});
decipher.setAuthTag(tag);
decipher.setAAD(aad, {
plaintextLength: ciphertext.length
});
const receivedPlaintext = decipher.update(ciphertext, null, 'utf8');
try {
decipher.final();
} catch (err) {
throw new Error('Authentication failed!', { cause: err });
}
console.log(receivedPlaintext);
```
## Crypto constants
The following constants exported by `crypto.constants` apply to various uses of
the `crypto`, `tls`, and `https` modules and are generally specific to OpenSSL.
### OpenSSL options
See the [list of SSL OP Flags][] for details.
<table>
<tr>
<th>Constant</th>
<th>Description</th>
</tr>
<tr>
<td><code>SSL_OP_ALL</code></td>
<td>Applies multiple bug workarounds within OpenSSL. See
<a href="https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html">https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html</a>
for detail.</td>
</tr>
<tr>
<td><code>SSL_OP_ALLOW_NO_DHE_KEX</code></td>
<td>Instructs OpenSSL to allow a non-[EC]DHE-based key exchange mode
for TLS v1.3</td>
</tr>
<tr>
<td><code>SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION</code></td>
<td>Allows legacy insecure renegotiation between OpenSSL and unpatched
clients or servers. See
<a href="https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html">https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html</a>.</td>
</tr>
<tr>
<td><code>SSL_OP_CIPHER_SERVER_PREFERENCE</code></td>
<td>Attempts to use the server's preferences instead of the client's when
selecting a cipher. Behavior depends on protocol version. See
<a href="https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html">https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html</a>.</td>
</tr>
<tr>
<td><code>SSL_OP_CISCO_ANYCONNECT</code></td>
<td>Instructs OpenSSL to use Cisco's "speshul" version of DTLS_BAD_VER.</td>
</tr>
<tr>
<td><code>SSL_OP_COOKIE_EXCHANGE</code></td>
<td>Instructs OpenSSL to turn on cookie exchange.</td>
</tr>
<tr>
<td><code>SSL_OP_CRYPTOPRO_TLSEXT_BUG</code></td>
<td>Instructs OpenSSL to add server-hello extension from an early version
of the cryptopro draft.</td>
</tr>
<tr>
<td><code>SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS</code></td>
<td>Instructs OpenSSL to disable a SSL 3.0/TLS 1.0 vulnerability
workaround added in OpenSSL 0.9.6d.</td>
</tr>
<tr>
<td><code>SSL_OP_EPHEMERAL_RSA</code></td>
<td>Instructs OpenSSL to always use the tmp_rsa key when performing RSA
operations.</td>
</tr>
<tr>
<td><code>SSL_OP_LEGACY_SERVER_CONNECT</code></td>
<td>Allows initial connection to servers that do not support RI.</td>
</tr>
<tr>
<td><code>SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_MICROSOFT_SESS_ID_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_MSIE_SSLV2_RSA_PADDING</code></td>
<td>Instructs OpenSSL to disable the workaround for a man-in-the-middle
protocol-version vulnerability in the SSL 2.0 server implementation.</td>
</tr>
<tr>
<td><code>SSL_OP_NETSCAPE_CA_DN_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_NETSCAPE_CHALLENGE_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_NO_COMPRESSION</code></td>
<td>Instructs OpenSSL to disable support for SSL/TLS compression.</td>
</tr>
<tr>
<td><code>SSL_OP_NO_ENCRYPT_THEN_MAC</code></td>
<td>Instructs OpenSSL to disable encrypt-then-MAC.</td>
</tr>
<tr>
<td><code>SSL_OP_NO_QUERY_MTU</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_NO_RENEGOTIATION</code></td>
<td>Instructs OpenSSL to disable renegotiation.</td>
</tr>
<tr>
<td><code>SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION</code></td>
<td>Instructs OpenSSL to always start a new session when performing
renegotiation.</td>
</tr>
<tr>
<td><code>SSL_OP_NO_SSLv2</code></td>
<td>Instructs OpenSSL to turn off SSL v2</td>
</tr>
<tr>
<td><code>SSL_OP_NO_SSLv3</code></td>
<td>Instructs OpenSSL to turn off SSL v3</td>
</tr>
<tr>
<td><code>SSL_OP_NO_TICKET</code></td>
<td>Instructs OpenSSL to disable use of RFC4507bis tickets.</td>
</tr>
<tr>
<td><code>SSL_OP_NO_TLSv1</code></td>
<td>Instructs OpenSSL to turn off TLS v1</td>
</tr>
<tr>
<td><code>SSL_OP_NO_TLSv1_1</code></td>
<td>Instructs OpenSSL to turn off TLS v1.1</td>
</tr>
<tr>
<td><code>SSL_OP_NO_TLSv1_2</code></td>
<td>Instructs OpenSSL to turn off TLS v1.2</td>
</tr>
<tr>
<td><code>SSL_OP_NO_TLSv1_3</code></td>
<td>Instructs OpenSSL to turn off TLS v1.3</td>
</tr>
<tr>
<td><code>SSL_OP_PKCS1_CHECK_1</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_PKCS1_CHECK_2</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_PRIORITIZE_CHACHA</code></td>
<td>Instructs OpenSSL server to prioritize ChaCha20-Poly1305
when the client does.
This option has no effect if
<code>SSL_OP_CIPHER_SERVER_PREFERENCE</code>
is not enabled.</td>
</tr>
<tr>
<td><code>SSL_OP_SINGLE_DH_USE</code></td>
<td>Instructs OpenSSL to always create a new key when using
temporary/ephemeral DH parameters.</td>
</tr>
<tr>
<td><code>SSL_OP_SINGLE_ECDH_USE</code></td>
<td>Instructs OpenSSL to always create a new key when using
temporary/ephemeral ECDH parameters.</td>
</tr>
<tr>
<td><code>SSL_OP_SSLEAY_080_CLIENT_DH_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_TLS_BLOCK_PADDING_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_TLS_D5_BUG</code></td>
<td></td>
</tr>
<tr>
<td><code>SSL_OP_TLS_ROLLBACK_BUG</code></td>
<td>Instructs OpenSSL to disable version rollback attack detection.</td>
</tr>
</table>
### OpenSSL engine constants
<table>
<tr>
<th>Constant</th>
<th>Description</th>
</tr>
<tr>
<td><code>ENGINE_METHOD_RSA</code></td>
<td>Limit engine usage to RSA</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_DSA</code></td>
<td>Limit engine usage to DSA</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_DH</code></td>
<td>Limit engine usage to DH</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_RAND</code></td>
<td>Limit engine usage to RAND</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_EC</code></td>
<td>Limit engine usage to EC</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_CIPHERS</code></td>
<td>Limit engine usage to CIPHERS</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_DIGESTS</code></td>
<td>Limit engine usage to DIGESTS</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_PKEY_METHS</code></td>
<td>Limit engine usage to PKEY_METHDS</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_PKEY_ASN1_METHS</code></td>
<td>Limit engine usage to PKEY_ASN1_METHS</td>
</tr>
<tr>
<td><code>ENGINE_METHOD_ALL</code></td>
<td></td>
</tr>
<tr>
<td><code>ENGINE_METHOD_NONE</code></td>
<td></td>
</tr>
</table>
### Other OpenSSL constants
<table>
<tr>
<th>Constant</th>
<th>Description</th>
</tr>
<tr>
<td><code>DH_CHECK_P_NOT_SAFE_PRIME</code></td>
<td></td>
</tr>
<tr>
<td><code>DH_CHECK_P_NOT_PRIME</code></td>
<td></td>
</tr>
<tr>
<td><code>DH_UNABLE_TO_CHECK_GENERATOR</code></td>
<td></td>
</tr>
<tr>
<td><code>DH_NOT_SUITABLE_GENERATOR</code></td>
<td></td>
</tr>
<tr>
<td><code>ALPN_ENABLED</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_PKCS1_PADDING</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_SSLV23_PADDING</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_NO_PADDING</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_PKCS1_OAEP_PADDING</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_X931_PADDING</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_PKCS1_PSS_PADDING</code></td>
<td></td>
</tr>
<tr>
<td><code>RSA_PSS_SALTLEN_DIGEST</code></td>
<td>Sets the salt length for <code>RSA_PKCS1_PSS_PADDING</code> to the
digest size when signing or verifying.</td>
</tr>
<tr>
<td><code>RSA_PSS_SALTLEN_MAX_SIGN</code></td>
<td>Sets the salt length for <code>RSA_PKCS1_PSS_PADDING</code> to the
maximum permissible value when signing data.</td>
</tr>
<tr>
<td><code>RSA_PSS_SALTLEN_AUTO</code></td>
<td>Causes the salt length for <code>RSA_PKCS1_PSS_PADDING</code> to be
determined automatically when verifying a signature.</td>
</tr>
<tr>
<td><code>POINT_CONVERSION_COMPRESSED</code></td>
<td></td>
</tr>
<tr>
<td><code>POINT_CONVERSION_UNCOMPRESSED</code></td>
<td></td>
</tr>
<tr>
<td><code>POINT_CONVERSION_HYBRID</code></td>
<td></td>
</tr>
</table>
### Node.js crypto constants
<table>
<tr>
<th>Constant</th>
<th>Description</th>
</tr>
<tr>
<td><code>defaultCoreCipherList</code></td>
<td>Specifies the built-in default cipher list used by Node.js.</td>
</tr>
<tr>
<td><code>defaultCipherList</code></td>
<td>Specifies the active default cipher list used by the current Node.js
process.</td>
</tr>
</table>
[AEAD algorithms]: https://en.wikipedia.org/wiki/Authenticated_encryption
[CCM mode]: #ccm-mode
[CVE-2021-44532]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44532
[Caveats]: #support-for-weak-or-compromised-algorithms
[Crypto constants]: #crypto-constants
[HTML 5.2]: https://www.w3.org/TR/html52/changes.html#features-removed
[HTML5's `keygen` element]: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/keygen
[JWK]: https://tools.ietf.org/html/rfc7517
[NIST SP 800-131A]: https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-131Ar1.pdf
[NIST SP 800-132]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf
[NIST SP 800-38D]: https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf
[Nonce-Disrespecting Adversaries]: https://github.com/nonce-disrespect/nonce-disrespect
[OpenSSL's SPKAC implementation]: https://www.openssl.org/docs/man1.1.0/apps/openssl-spkac.html
[RFC 1421]: https://www.rfc-editor.org/rfc/rfc1421.txt
[RFC 2412]: https://www.rfc-editor.org/rfc/rfc2412.txt
[RFC 2818]: https://www.rfc-editor.org/rfc/rfc2818.txt
[RFC 3526]: https://www.rfc-editor.org/rfc/rfc3526.txt
[RFC 3610]: https://www.rfc-editor.org/rfc/rfc3610.txt
[RFC 4055]: https://www.rfc-editor.org/rfc/rfc4055.txt
[RFC 4122]: https://www.rfc-editor.org/rfc/rfc4122.txt
[RFC 5208]: https://www.rfc-editor.org/rfc/rfc5208.txt
[RFC 5280]: https://www.rfc-editor.org/rfc/rfc5280.txt
[Web Crypto API documentation]: webcrypto.md
[`BN_is_prime_ex`]: https://www.openssl.org/docs/man1.1.1/man3/BN_is_prime_ex.html
[`Buffer`]: buffer.md
[`EVP_BytesToKey`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_BytesToKey.html
[`KeyObject`]: #class-keyobject
[`Sign`]: #class-sign
[`String.prototype.normalize()`]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize
[`UV_THREADPOOL_SIZE`]: cli.md#uv_threadpool_sizesize
[`Verify`]: #class-verify
[`cipher.final()`]: #cipherfinaloutputencoding
[`cipher.update()`]: #cipherupdatedata-inputencoding-outputencoding
[`crypto.createCipher()`]: #cryptocreatecipheralgorithm-password-options
[`crypto.createCipheriv()`]: #cryptocreatecipherivalgorithm-key-iv-options
[`crypto.createDecipher()`]: #cryptocreatedecipheralgorithm-password-options
[`crypto.createDecipheriv()`]: #cryptocreatedecipherivalgorithm-key-iv-options
[`crypto.createDiffieHellman()`]: #cryptocreatediffiehellmanprime-primeencoding-generator-generatorencoding
[`crypto.createECDH()`]: #cryptocreateecdhcurvename
[`crypto.createHash()`]: #cryptocreatehashalgorithm-options
[`crypto.createHmac()`]: #cryptocreatehmacalgorithm-key-options
[`crypto.createPrivateKey()`]: #cryptocreateprivatekeykey
[`crypto.createPublicKey()`]: #cryptocreatepublickeykey
[`crypto.createSecretKey()`]: #cryptocreatesecretkeykey-encoding
[`crypto.createSign()`]: #cryptocreatesignalgorithm-options
[`crypto.createVerify()`]: #cryptocreateverifyalgorithm-options
[`crypto.getCurves()`]: #cryptogetcurves
[`crypto.getDiffieHellman()`]: #cryptogetdiffiehellmangroupname
[`crypto.getHashes()`]: #cryptogethashes
[`crypto.privateDecrypt()`]: #cryptoprivatedecryptprivatekey-buffer
[`crypto.privateEncrypt()`]: #cryptoprivateencryptprivatekey-buffer
[`crypto.publicDecrypt()`]: #cryptopublicdecryptkey-buffer
[`crypto.publicEncrypt()`]: #cryptopublicencryptkey-buffer
[`crypto.randomBytes()`]: #cryptorandombytessize-callback
[`crypto.randomFill()`]: #cryptorandomfillbuffer-offset-size-callback
[`crypto.scrypt()`]: #cryptoscryptpassword-salt-keylen-options-callback
[`crypto.webcrypto.getRandomValues()`]: webcrypto.md#cryptogetrandomvaluestypedarray
[`crypto.webcrypto.subtle`]: webcrypto.md#class-subtlecrypto
[`decipher.final()`]: #decipherfinaloutputencoding
[`decipher.update()`]: #decipherupdatedata-inputencoding-outputencoding
[`diffieHellman.setPublicKey()`]: #diffiehellmansetpublickeypublickey-encoding
[`ecdh.generateKeys()`]: #ecdhgeneratekeysencoding-format
[`ecdh.setPrivateKey()`]: #ecdhsetprivatekeyprivatekey-encoding
[`hash.digest()`]: #hashdigestencoding
[`hash.update()`]: #hashupdatedata-inputencoding
[`hmac.digest()`]: #hmacdigestencoding
[`hmac.update()`]: #hmacupdatedata-inputencoding
[`keyObject.export()`]: #keyobjectexportoptions
[`postMessage()`]: worker_threads.md#portpostmessagevalue-transferlist
[`sign.sign()`]: #signsignprivatekey-outputencoding
[`sign.update()`]: #signupdatedata-inputencoding
[`stream.Writable` options]: stream.md#new-streamwritableoptions
[`stream.transform` options]: stream.md#new-streamtransformoptions
[`util.promisify()`]: util.md#utilpromisifyoriginal
[`verify.update()`]: #verifyupdatedata-inputencoding
[`verify.verify()`]: #verifyverifyobject-signature-signatureencoding
[caveats when using strings as inputs to cryptographic APIs]: #using-strings-as-inputs-to-cryptographic-apis
[certificate object]: tls.md#certificate-object
[encoding]: buffer.md#buffers-and-character-encodings
[initialization vector]: https://en.wikipedia.org/wiki/Initialization_vector
[legacy provider]: cli.md#--openssl-legacy-provider
[list of SSL OP Flags]: https://wiki.openssl.org/index.php/List_of_SSL_OP_Flags#Table_of_Options
[modulo bias]: https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle#Modulo_bias
[safe integers]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isSafeInteger
[scrypt]: https://en.wikipedia.org/wiki/Scrypt
[stream]: stream.md
[stream-writable-write]: stream.md#writablewritechunk-encoding-callback
|