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
|
/*
* Main program to compile ssh/zlib.c into a zlib decoding tool.
*
* This is potentially a handy tool in its own right for picking apart
* Zip files or PDFs or PNGs, because it accepts the bare Deflate
* format and the zlib wrapper format, unlike 'zcat' which accepts
* only the gzip wrapper format.
*
* It's also useful as a means for a fuzzer to get reasonably direct
* access to PuTTY's zlib decompressor.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "defs.h"
#include "ssh.h"
void out_of_memory(void)
{
fprintf(stderr, "Out of memory!\n");
exit(1);
}
void dputs(const char *buf)
{
fputs(buf, stderr);
}
int main(int argc, char **argv)
{
unsigned char buf[16], *outbuf;
int ret, outlen;
ssh_decompressor *handle;
int noheader = false, opts = true;
char *filename = NULL;
FILE *fp;
while (--argc) {
char *p = *++argv;
if (p[0] == '-' && opts) {
if (!strcmp(p, "-d")) {
noheader = true;
} else if (!strcmp(p, "--")) {
opts = false; /* next thing is filename */
} else if (!strcmp(p, "--help")) {
printf("usage: testzlib decode zlib (RFC1950) data"
" from standard input\n");
printf(" testzlib -d decode Deflate (RFC1951) data"
" from standard input\n");
printf(" testzlib --help display this text\n");
return 0;
} else {
fprintf(stderr, "unknown command line option '%s'\n", p);
return 1;
}
} else if (!filename) {
filename = p;
} else {
fprintf(stderr, "can only handle one filename\n");
return 1;
}
}
handle = ssh_decompressor_new(&ssh_zlib);
if (noheader) {
/*
* Provide missing zlib header if -d was specified.
*/
static const unsigned char ersatz_zlib_header[] = { 0x78, 0x9C };
ssh_decompressor_decompress(
handle, ersatz_zlib_header, sizeof(ersatz_zlib_header),
&outbuf, &outlen);
assert(outlen == 0);
}
if (filename)
fp = fopen(filename, "rb");
else
fp = stdin;
if (!fp) {
assert(filename);
fprintf(stderr, "unable to open '%s'\n", filename);
return 1;
}
while (1) {
ret = fread(buf, 1, sizeof(buf), fp);
if (ret <= 0)
break;
ssh_decompressor_decompress(handle, buf, ret, &outbuf, &outlen);
if (outbuf) {
if (outlen)
fwrite(outbuf, 1, outlen, stdout);
sfree(outbuf);
} else {
fprintf(stderr, "decoding error\n");
fclose(fp);
return 1;
}
}
ssh_decompressor_free(handle);
if (filename)
fclose(fp);
return 0;
}
|
