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authorNick Mathewson <nickm@torproject.org>2017-04-25 09:41:23 -0400
committerNick Mathewson <nickm@torproject.org>2017-04-25 10:50:50 -0400
commit880fb3e3a9aba21c0b36aa4aa5659432e90eb827 (patch)
treeb742f5773bf54cbf34db66aae503953772e74761 /src/common/compress_zlib.c
parent91dd4a00f7d4891e24187a849933547128aeeb9f (diff)
downloadtor-880fb3e3a9aba21c0b36aa4aa5659432e90eb827.tar.gz
tor-880fb3e3a9aba21c0b36aa4aa5659432e90eb827.zip
Combine all *compress/*uncompress backend function into one
Since we have a streaming API for each compression backend, we don't need a non-streaming API for each: we can build a common non-streaming API at the front-end.
Diffstat (limited to 'src/common/compress_zlib.c')
-rw-r--r--src/common/compress_zlib.c254
1 files changed, 0 insertions, 254 deletions
diff --git a/src/common/compress_zlib.c b/src/common/compress_zlib.c
index faa179f7c1..37768ee49e 100644
--- a/src/common/compress_zlib.c
+++ b/src/common/compress_zlib.c
@@ -102,260 +102,6 @@ tor_zlib_get_header_version_str(void)
return ZLIB_VERSION;
}
-/** Given <b>in_len</b> bytes at <b>in</b>, compress them into a newly
- * allocated buffer, using the method described in <b>method</b>. Store the
- * compressed string in *<b>out</b>, and its length in *<b>out_len</b>. Return
- * 0 on success, -1 on failure.
- */
-int
-tor_zlib_compress(char **out, size_t *out_len,
- const char *in, size_t in_len,
- compress_method_t method)
-{
- struct z_stream_s *stream = NULL;
- size_t out_size, old_size;
- off_t offset;
-
- tor_assert(out);
- tor_assert(out_len);
- tor_assert(in);
- tor_assert(in_len < UINT_MAX);
-
- *out = NULL;
-
- stream = tor_malloc_zero(sizeof(struct z_stream_s));
- stream->zalloc = Z_NULL;
- stream->zfree = Z_NULL;
- stream->opaque = NULL;
- stream->next_in = (unsigned char*) in;
- stream->avail_in = (unsigned int)in_len;
-
- if (deflateInit2(stream, Z_BEST_COMPRESSION, Z_DEFLATED,
- method_bits(method, HIGH_COMPRESSION),
- memory_level(HIGH_COMPRESSION),
- Z_DEFAULT_STRATEGY) != Z_OK) {
- //LCOV_EXCL_START -- we can only provoke failure by giving junk arguments.
- log_warn(LD_GENERAL, "Error from deflateInit2: %s",
- stream->msg?stream->msg:"<no message>");
- goto err;
- //LCOV_EXCL_STOP
- }
-
- /* Guess 50% compression. */
- out_size = in_len / 2;
- if (out_size < 1024) out_size = 1024;
- *out = tor_malloc(out_size);
- stream->next_out = (unsigned char*)*out;
- stream->avail_out = (unsigned int)out_size;
-
- while (1) {
- switch (deflate(stream, Z_FINISH))
- {
- case Z_STREAM_END:
- goto done;
- case Z_OK:
- /* In case zlib doesn't work as I think .... */
- if (stream->avail_out >= stream->avail_in+16)
- break;
- case Z_BUF_ERROR:
- offset = stream->next_out - ((unsigned char*)*out);
- old_size = out_size;
- out_size *= 2;
- if (out_size < old_size) {
- log_warn(LD_GENERAL, "Size overflow in compression.");
- goto err;
- }
- *out = tor_realloc(*out, out_size);
- stream->next_out = (unsigned char*)(*out + offset);
- if (out_size - offset > UINT_MAX) {
- log_warn(LD_BUG, "Ran over unsigned int limit of zlib while "
- "uncompressing.");
- goto err;
- }
- stream->avail_out = (unsigned int)(out_size - offset);
- break;
- default:
- log_warn(LD_GENERAL, "Gzip compression didn't finish: %s",
- stream->msg ? stream->msg : "<no message>");
- goto err;
- }
- }
- done:
- *out_len = stream->total_out;
-#if defined(OpenBSD)
- /* "Hey Rocky! Watch me change an unsigned field to a signed field in a
- * third-party API!"
- * "Oh, that trick will just make people do unsafe casts to the unsigned
- * type in their cross-platform code!"
- * "Don't be foolish. I'm _sure_ they'll have the good sense to make sure
- * the newly unsigned field isn't negative." */
- tor_assert(stream->total_out >= 0);
-#endif
- if (deflateEnd(stream)!=Z_OK) {
- // LCOV_EXCL_START -- unreachable if we handled the zlib structure right
- tor_assert_nonfatal_unreached();
- log_warn(LD_BUG, "Error freeing gzip structures");
- goto err;
- // LCOV_EXCL_STOP
- }
- tor_free(stream);
-
- if (tor_compress_is_compression_bomb(*out_len, in_len)) {
- log_warn(LD_BUG, "We compressed something and got an insanely high "
- "compression factor; other Tors would think this was a zlib bomb.");
- goto err;
- }
-
- return 0;
- err:
- if (stream) {
- deflateEnd(stream);
- tor_free(stream);
- }
- tor_free(*out);
- return -1;
-}
-
-/** Given an Zlib/Gzip compressed string of total length <b>in_len</b> bytes
- * at <b>in</b>, uncompress them into a newly allocated buffer. Store the
- * uncompressed string in *<b>out</b>, and its length in *<b>out_len</b>.
- * Return 0 on success, -1 on failure.
- *
- * If <b>complete_only</b> is true, we consider a truncated input as a failure;
- * otherwise we decompress as much as we can. Warn about truncated or corrupt
- * inputs at <b>protocol_warn_level</b>.
- */
-int
-tor_zlib_uncompress(char **out, size_t *out_len,
- const char *in, size_t in_len,
- compress_method_t method,
- int complete_only,
- int protocol_warn_level)
-{
- struct z_stream_s *stream = NULL;
- size_t out_size, old_size;
- off_t offset;
- int r;
-
- tor_assert(out);
- tor_assert(out_len);
- tor_assert(in);
- tor_assert(in_len < UINT_MAX);
-
- *out = NULL;
-
- stream = tor_malloc_zero(sizeof(struct z_stream_s));
- stream->zalloc = Z_NULL;
- stream->zfree = Z_NULL;
- stream->opaque = NULL;
- stream->next_in = (unsigned char*) in;
- stream->avail_in = (unsigned int)in_len;
-
- if (inflateInit2(stream,
- method_bits(method, HIGH_COMPRESSION)) != Z_OK) {
- // LCOV_EXCL_START -- can only hit this if we give bad inputs.
- log_warn(LD_GENERAL, "Error from inflateInit2: %s",
- stream->msg?stream->msg:"<no message>");
- goto err;
- // LCOV_EXCL_STOP
- }
-
- out_size = in_len * 2; /* guess 50% compression. */
- if (out_size < 1024) out_size = 1024;
- if (out_size >= SIZE_T_CEILING || out_size > UINT_MAX)
- goto err;
-
- *out = tor_malloc(out_size);
- stream->next_out = (unsigned char*)*out;
- stream->avail_out = (unsigned int)out_size;
-
- while (1) {
- switch (inflate(stream, complete_only ? Z_FINISH : Z_SYNC_FLUSH))
- {
- case Z_STREAM_END:
- if (stream->avail_in == 0)
- goto done;
- /* There may be more compressed data here. */
- if ((r = inflateEnd(stream)) != Z_OK) {
- log_warn(LD_BUG, "Error freeing gzip structures");
- goto err;
- }
- if (inflateInit2(stream,
- method_bits(method,HIGH_COMPRESSION)) != Z_OK) {
- log_warn(LD_GENERAL, "Error from second inflateInit2: %s",
- stream->msg?stream->msg:"<no message>");
- goto err;
- }
- break;
- case Z_OK:
- if (!complete_only && stream->avail_in == 0)
- goto done;
- /* In case zlib doesn't work as I think.... */
- if (stream->avail_out >= stream->avail_in+16)
- break;
- case Z_BUF_ERROR:
- if (stream->avail_out > 0) {
- log_fn(protocol_warn_level, LD_PROTOCOL,
- "possible truncated or corrupt zlib data");
- goto err;
- }
- offset = stream->next_out - (unsigned char*)*out;
- old_size = out_size;
- out_size *= 2;
- if (out_size < old_size) {
- log_warn(LD_GENERAL, "Size overflow in uncompression.");
- goto err;
- }
- if (tor_compress_is_compression_bomb(in_len, out_size)) {
- log_warn(LD_GENERAL, "Input looks like a possible zlib bomb; "
- "not proceeding.");
- goto err;
- }
- if (out_size >= SIZE_T_CEILING) {
- log_warn(LD_BUG, "Hit SIZE_T_CEILING limit while uncompressing.");
- goto err;
- }
- *out = tor_realloc(*out, out_size);
- stream->next_out = (unsigned char*)(*out + offset);
- if (out_size - offset > UINT_MAX) {
- log_warn(LD_BUG, "Ran over unsigned int limit of zlib while "
- "uncompressing.");
- goto err;
- }
- stream->avail_out = (unsigned int)(out_size - offset);
- break;
- default:
- log_warn(LD_GENERAL, "Gzip decompression returned an error: %s",
- stream->msg ? stream->msg : "<no message>");
- goto err;
- }
- }
- done:
- *out_len = stream->next_out - (unsigned char*)*out;
- r = inflateEnd(stream);
- tor_free(stream);
- if (r != Z_OK) {
- log_warn(LD_BUG, "Error freeing gzip structures");
- goto err;
- }
-
- /* NUL-terminate output. */
- if (out_size == *out_len)
- *out = tor_realloc(*out, out_size + 1);
- (*out)[*out_len] = '\0';
-
- return 0;
- err:
- if (stream) {
- inflateEnd(stream);
- tor_free(stream);
- }
- if (*out) {
- tor_free(*out);
- }
- return -1;
-}
-
/** Internal zlib state for an incremental compression/decompression.
* The body of this struct is not exposed. */
struct tor_zlib_compress_state_t {