diff options
Diffstat (limited to 'core/src/main/java/org/bouncycastle/crypto/digests/SHA1Digest.java')
| -rw-r--r-- | core/src/main/java/org/bouncycastle/crypto/digests/SHA1Digest.java | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/core/src/main/java/org/bouncycastle/crypto/digests/SHA1Digest.java b/core/src/main/java/org/bouncycastle/crypto/digests/SHA1Digest.java new file mode 100644 index 00000000..21b1024e --- /dev/null +++ b/core/src/main/java/org/bouncycastle/crypto/digests/SHA1Digest.java @@ -0,0 +1,309 @@ +package org.bouncycastle.crypto.digests; + +import org.bouncycastle.crypto.util.Pack; +import org.bouncycastle.util.Memoable; + +/** + * implementation of SHA-1 as outlined in "Handbook of Applied Cryptography", pages 346 - 349. + * + * It is interesting to ponder why the, apart from the extra IV, the other difference here from MD5 + * is the "endianness" of the word processing! + */ +public class SHA1Digest + extends GeneralDigest +{ + private static final int DIGEST_LENGTH = 20; + + private int H1, H2, H3, H4, H5; + + private int[] X = new int[80]; + private int xOff; + + /** + * Standard constructor + */ + public SHA1Digest() + { + reset(); + } + + /** + * Copy constructor. This will copy the state of the provided + * message digest. + */ + public SHA1Digest(SHA1Digest t) + { + super(t); + + copyIn(t); + } + + private void copyIn(SHA1Digest t) + { + H1 = t.H1; + H2 = t.H2; + H3 = t.H3; + H4 = t.H4; + H5 = t.H5; + + System.arraycopy(t.X, 0, X, 0, t.X.length); + xOff = t.xOff; + } + + public String getAlgorithmName() + { + return "SHA-1"; + } + + public int getDigestSize() + { + return DIGEST_LENGTH; + } + + protected void processWord( + byte[] in, + int inOff) + { + // Note: Inlined for performance +// X[xOff] = Pack.bigEndianToInt(in, inOff); + int n = in[ inOff] << 24; + n |= (in[++inOff] & 0xff) << 16; + n |= (in[++inOff] & 0xff) << 8; + n |= (in[++inOff] & 0xff); + X[xOff] = n; + + if (++xOff == 16) + { + processBlock(); + } + } + + protected void processLength( + long bitLength) + { + if (xOff > 14) + { + processBlock(); + } + + X[14] = (int)(bitLength >>> 32); + X[15] = (int)(bitLength & 0xffffffff); + } + + public int doFinal( + byte[] out, + int outOff) + { + finish(); + + Pack.intToBigEndian(H1, out, outOff); + Pack.intToBigEndian(H2, out, outOff + 4); + Pack.intToBigEndian(H3, out, outOff + 8); + Pack.intToBigEndian(H4, out, outOff + 12); + Pack.intToBigEndian(H5, out, outOff + 16); + + reset(); + + return DIGEST_LENGTH; + } + + /** + * reset the chaining variables + */ + public void reset() + { + super.reset(); + + H1 = 0x67452301; + H2 = 0xefcdab89; + H3 = 0x98badcfe; + H4 = 0x10325476; + H5 = 0xc3d2e1f0; + + xOff = 0; + for (int i = 0; i != X.length; i++) + { + X[i] = 0; + } + } + + // + // Additive constants + // + private static final int Y1 = 0x5a827999; + private static final int Y2 = 0x6ed9eba1; + private static final int Y3 = 0x8f1bbcdc; + private static final int Y4 = 0xca62c1d6; + + private int f( + int u, + int v, + int w) + { + return ((u & v) | ((~u) & w)); + } + + private int h( + int u, + int v, + int w) + { + return (u ^ v ^ w); + } + + private int g( + int u, + int v, + int w) + { + return ((u & v) | (u & w) | (v & w)); + } + + protected void processBlock() + { + // + // expand 16 word block into 80 word block. + // + for (int i = 16; i < 80; i++) + { + int t = X[i - 3] ^ X[i - 8] ^ X[i - 14] ^ X[i - 16]; + X[i] = t << 1 | t >>> 31; + } + + // + // set up working variables. + // + int A = H1; + int B = H2; + int C = H3; + int D = H4; + int E = H5; + + // + // round 1 + // + int idx = 0; + + for (int j = 0; j < 4; j++) + { + // E = rotateLeft(A, 5) + f(B, C, D) + E + X[idx++] + Y1 + // B = rotateLeft(B, 30) + E += (A << 5 | A >>> 27) + f(B, C, D) + X[idx++] + Y1; + B = B << 30 | B >>> 2; + + D += (E << 5 | E >>> 27) + f(A, B, C) + X[idx++] + Y1; + A = A << 30 | A >>> 2; + + C += (D << 5 | D >>> 27) + f(E, A, B) + X[idx++] + Y1; + E = E << 30 | E >>> 2; + + B += (C << 5 | C >>> 27) + f(D, E, A) + X[idx++] + Y1; + D = D << 30 | D >>> 2; + + A += (B << 5 | B >>> 27) + f(C, D, E) + X[idx++] + Y1; + C = C << 30 | C >>> 2; + } + + // + // round 2 + // + for (int j = 0; j < 4; j++) + { + // E = rotateLeft(A, 5) + h(B, C, D) + E + X[idx++] + Y2 + // B = rotateLeft(B, 30) + E += (A << 5 | A >>> 27) + h(B, C, D) + X[idx++] + Y2; + B = B << 30 | B >>> 2; + + D += (E << 5 | E >>> 27) + h(A, B, C) + X[idx++] + Y2; + A = A << 30 | A >>> 2; + + C += (D << 5 | D >>> 27) + h(E, A, B) + X[idx++] + Y2; + E = E << 30 | E >>> 2; + + B += (C << 5 | C >>> 27) + h(D, E, A) + X[idx++] + Y2; + D = D << 30 | D >>> 2; + + A += (B << 5 | B >>> 27) + h(C, D, E) + X[idx++] + Y2; + C = C << 30 | C >>> 2; + } + + // + // round 3 + // + for (int j = 0; j < 4; j++) + { + // E = rotateLeft(A, 5) + g(B, C, D) + E + X[idx++] + Y3 + // B = rotateLeft(B, 30) + E += (A << 5 | A >>> 27) + g(B, C, D) + X[idx++] + Y3; + B = B << 30 | B >>> 2; + + D += (E << 5 | E >>> 27) + g(A, B, C) + X[idx++] + Y3; + A = A << 30 | A >>> 2; + + C += (D << 5 | D >>> 27) + g(E, A, B) + X[idx++] + Y3; + E = E << 30 | E >>> 2; + + B += (C << 5 | C >>> 27) + g(D, E, A) + X[idx++] + Y3; + D = D << 30 | D >>> 2; + + A += (B << 5 | B >>> 27) + g(C, D, E) + X[idx++] + Y3; + C = C << 30 | C >>> 2; + } + + // + // round 4 + // + for (int j = 0; j <= 3; j++) + { + // E = rotateLeft(A, 5) + h(B, C, D) + E + X[idx++] + Y4 + // B = rotateLeft(B, 30) + E += (A << 5 | A >>> 27) + h(B, C, D) + X[idx++] + Y4; + B = B << 30 | B >>> 2; + + D += (E << 5 | E >>> 27) + h(A, B, C) + X[idx++] + Y4; + A = A << 30 | A >>> 2; + + C += (D << 5 | D >>> 27) + h(E, A, B) + X[idx++] + Y4; + E = E << 30 | E >>> 2; + + B += (C << 5 | C >>> 27) + h(D, E, A) + X[idx++] + Y4; + D = D << 30 | D >>> 2; + + A += (B << 5 | B >>> 27) + h(C, D, E) + X[idx++] + Y4; + C = C << 30 | C >>> 2; + } + + + H1 += A; + H2 += B; + H3 += C; + H4 += D; + H5 += E; + + // + // reset start of the buffer. + // + xOff = 0; + for (int i = 0; i < 16; i++) + { + X[i] = 0; + } + } + + public Memoable copy() + { + return new SHA1Digest(this); + } + + public void reset(Memoable other) + { + SHA1Digest d = (SHA1Digest)other; + + super.copyIn(d); + copyIn(d); + } +} + + + + |