#include <stdlib.h>
#include <assert.h>
+#ifdef ZLIB_STANDALONE
+
+/*
+ * This module also makes a handy zlib decoding tool for when
+ * you're picking apart Zip files or PDFs or PNGs. If you compile
+ * it with ZLIB_STANDALONE defined, it builds on its own and
+ * becomes a command-line utility.
+ *
+ * Therefore, here I provide a self-contained implementation of the
+ * macros required from the rest of the PuTTY sources.
+ */
+#define snew(type) ( (type *) malloc(sizeof(type)) )
+#define snewn(n, type) ( (type *) malloc((n) * sizeof(type)) )
+#define sresize(x, n, type) ( (type *) realloc((x), (n) * sizeof(type)) )
+#define sfree(x) ( free((x)) )
+
+#else
#include "ssh.h"
+#endif
#ifndef FALSE
#define FALSE 0
struct LZ77InternalContext *st;
int i;
- st = (struct LZ77InternalContext *) smalloc(sizeof(*st));
+ st = snew(struct LZ77InternalContext);
if (!st)
return 0;
while (out->noutbits >= 8) {
if (out->outlen >= out->outsize) {
out->outsize = out->outlen + 64;
- out->outbuf = srealloc(out->outbuf, out->outsize);
+ out->outbuf = sresize(out->outbuf, out->outsize, unsigned char);
}
out->outbuf[out->outlen++] = (unsigned char) (out->outbits & 0xFF);
out->outbits >>= 8;
void *zlib_compress_init(void)
{
struct Outbuf *out;
- struct LZ77Context *ectx = smalloc(sizeof(struct LZ77Context));
+ struct LZ77Context *ectx = snew(struct LZ77Context);
lz77_init(ectx);
ectx->literal = zlib_literal;
ectx->match = zlib_match;
- out = smalloc(sizeof(struct Outbuf));
+ out = snew(struct Outbuf);
out->outbits = out->noutbits = 0;
out->firstblock = 1;
out->comp_disabled = FALSE;
{
struct LZ77Context *ectx = (struct LZ77Context *)handle;
sfree(ectx->userdata);
+ sfree(ectx->ictx);
+ sfree(ectx);
}
/*
int nsyms,
int pfx, int pfxbits, int bits)
{
- struct zlib_table *tab = smalloc(sizeof(struct zlib_table));
+ struct zlib_table *tab = snew(struct zlib_table);
int pfxmask = (1 << pfxbits) - 1;
int nbits, i, j, code;
- tab->table = smalloc((1 << bits) * sizeof(struct zlib_tableentry));
+ tab->table = snewn(1 << bits, struct zlib_tableentry);
tab->mask = (1 << bits) - 1;
for (code = 0; code <= tab->mask; code++) {
void *zlib_decompress_init(void)
{
- struct zlib_decompress_ctx *dctx =
- smalloc(sizeof(struct zlib_decompress_ctx));
+ struct zlib_decompress_ctx *dctx = snew(struct zlib_decompress_ctx);
unsigned char lengths[288];
memset(lengths, 8, 144);
void zlib_decompress_cleanup(void *handle)
{
struct zlib_decompress_ctx *dctx = (struct zlib_decompress_ctx *)handle;
-
+
if (dctx->currlentable && dctx->currlentable != dctx->staticlentable)
zlib_freetable(&dctx->currlentable);
if (dctx->currdisttable && dctx->currdisttable != dctx->staticdisttable)
zlib_freetable(&dctx->currdisttable);
if (dctx->lenlentable)
zlib_freetable(&dctx->lenlentable);
+ zlib_freetable(&dctx->staticlentable);
+ zlib_freetable(&dctx->staticdisttable);
sfree(dctx);
}
*nbitsp = nbits;
return ent->code;
}
+
+ if (!tab) {
+ /*
+ * There was a missing entry in the table, presumably
+ * due to an invalid Huffman table description, and the
+ * subsequent data has attempted to use the missing
+ * entry. Return a decoding failure.
+ */
+ return -2;
+ }
}
}
dctx->winpos = (dctx->winpos + 1) & (WINSIZE - 1);
if (dctx->outlen >= dctx->outsize) {
dctx->outsize = dctx->outlen + 512;
- dctx->outblk = srealloc(dctx->outblk, dctx->outsize);
+ dctx->outblk = sresize(dctx->outblk, dctx->outsize, unsigned char);
}
dctx->outblk[dctx->outlen++] = c;
}
{
struct zlib_decompress_ctx *dctx = (struct zlib_decompress_ctx *)handle;
const coderecord *rec;
- int code, blktype, rep, dist, nlen;
+ int code, blktype, rep, dist, nlen, header;
static const unsigned char lenlenmap[] = {
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
};
- dctx->outblk = NULL;
- dctx->outsize = dctx->outlen = 0;
+ dctx->outblk = snewn(256, unsigned char);
+ dctx->outsize = 256;
+ dctx->outlen = 0;
while (len > 0 || dctx->nbits > 0) {
while (dctx->nbits < 24 && len > 0) {
}
switch (dctx->state) {
case START:
- /* Expect 16-bit zlib header, which we'll dishonourably ignore. */
+ /* Expect 16-bit zlib header. */
if (dctx->nbits < 16)
goto finished; /* done all we can */
- EATBITS(16);
+
+ /*
+ * The header is stored as a big-endian 16-bit integer,
+ * in contrast to the general little-endian policy in
+ * the rest of the format :-(
+ */
+ header = (((dctx->bits & 0xFF00) >> 8) |
+ ((dctx->bits & 0x00FF) << 8));
+ EATBITS(16);
+
+ /*
+ * Check the header:
+ *
+ * - bits 8-11 should be 1000 (Deflate/RFC1951)
+ * - bits 12-15 should be at most 0111 (window size)
+ * - bit 5 should be zero (no dictionary present)
+ * - we don't care about bits 6-7 (compression rate)
+ * - bits 0-4 should be set up to make the whole thing
+ * a multiple of 31 (checksum).
+ */
+ if ((header & 0x0F00) != 0x0800 ||
+ (header & 0xF000) > 0x7000 ||
+ (header & 0x0020) != 0x0000 ||
+ (header % 31) != 0)
+ goto decode_error;
+
dctx->state = OUTSIDEBLK;
break;
case OUTSIDEBLK:
zlib_huflookup(&dctx->bits, &dctx->nbits, dctx->lenlentable);
if (code == -1)
goto finished;
+ if (code == -2)
+ goto decode_error;
if (code < 16)
dctx->lengths[dctx->lenptr++] = code;
else {
zlib_huflookup(&dctx->bits, &dctx->nbits, dctx->currlentable);
if (code == -1)
goto finished;
+ if (code == -2)
+ goto decode_error;
if (code < 256)
zlib_emit_char(dctx, code);
else if (code == 256) {
dctx->currdisttable);
if (code == -1)
goto finished;
+ if (code == -2)
+ goto decode_error;
dctx->state = GOTDISTSYM;
dctx->sym = code;
break;
finished:
*outblock = dctx->outblk;
*outlen = dctx->outlen;
-
return 1;
+
+ decode_error:
+ sfree(dctx->outblk);
+ *outblock = dctx->outblk = NULL;
+ *outlen = 0;
+ return 0;
+}
+
+#ifdef ZLIB_STANDALONE
+
+#include <stdio.h>
+#include <string.h>
+
+int main(int argc, char **argv)
+{
+ unsigned char buf[16], *outbuf;
+ int ret, outlen;
+ void *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 {
+ 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 = zlib_decompress_init();
+
+ if (noheader) {
+ /*
+ * Provide missing zlib header if -d was specified.
+ */
+ zlib_decompress_block(handle, "\x78\x9C", 2, &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;
+ zlib_decompress_block(handle, buf, ret, &outbuf, &outlen);
+ if (outbuf) {
+ if (outlen)
+ fwrite(outbuf, 1, outlen, stdout);
+ sfree(outbuf);
+ } else {
+ fprintf(stderr, "decoding error\n");
+ return 1;
+ }
+ }
+
+ zlib_decompress_cleanup(handle);
+
+ if (filename)
+ fclose(fp);
+
+ return 0;
}
+#else
+
const struct ssh_compress ssh_zlib = {
"zlib",
zlib_compress_init,
zlib_disable_compression,
"zlib (RFC1950)"
};
+
+#endif