aboutsummaryrefslogtreecommitdiff
path: root/src/common/torgzip.c
diff options
context:
space:
mode:
authorAlexander Færøy <ahf@torproject.org>2017-04-18 03:21:53 +0200
committerNick Mathewson <nickm@torproject.org>2017-04-25 08:06:01 -0400
commit04583df4520705bc171be9b720344167029292cb (patch)
tree21d5ce9cfe8eac60cf07e877e038d3a6becb5fee /src/common/torgzip.c
parent9d5bc1a9354637aa59025f61e577c6d42f8c53ba (diff)
downloadtor-04583df4520705bc171be9b720344167029292cb.tar.gz
tor-04583df4520705bc171be9b720344167029292cb.zip
Rename the `torgzip` module to `compress`.
See https://bugs.torproject.org/21663
Diffstat (limited to 'src/common/torgzip.c')
-rw-r--r--src/common/torgzip.c220
1 files changed, 0 insertions, 220 deletions
diff --git a/src/common/torgzip.c b/src/common/torgzip.c
deleted file mode 100644
index d760cd9546..0000000000
--- a/src/common/torgzip.c
+++ /dev/null
@@ -1,220 +0,0 @@
-/* Copyright (c) 2004, Roger Dingledine.
- * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
- * Copyright (c) 2007-2017, The Tor Project, Inc. */
-/* See LICENSE for licensing information */
-
-/**
- * \file torgzip.c
- * \brief A simple in-memory gzip implementation.
- **/
-
-#include "orconfig.h"
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <assert.h>
-#include <string.h>
-#include "torint.h"
-
-#ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
-#endif
-
-#include "util.h"
-#include "torlog.h"
-#include "torgzip.h"
-#include "compress_zlib.h"
-
-/** @{ */
-/* These macros define the maximum allowable compression factor. Anything of
- * size greater than CHECK_FOR_COMPRESSION_BOMB_AFTER is not allowed to
- * have an uncompression factor (uncompressed size:compressed size ratio) of
- * any greater than MAX_UNCOMPRESSION_FACTOR.
- *
- * Picking a value for MAX_UNCOMPRESSION_FACTOR is a trade-off: we want it to
- * be small to limit the attack multiplier, but we also want it to be large
- * enough so that no legitimate document --even ones we might invent in the
- * future -- ever compresses by a factor of greater than
- * MAX_UNCOMPRESSION_FACTOR. Within those parameters, there's a reasonably
- * large range of possible values. IMO, anything over 8 is probably safe; IMO
- * anything under 50 is probably sufficient.
- */
-#define MAX_UNCOMPRESSION_FACTOR 25
-#define CHECK_FOR_COMPRESSION_BOMB_AFTER (1024*64)
-/** @} */
-
-/** Return true if uncompressing an input of size <b>in_size</b> to an input of
- * size at least <b>size_out</b> looks like a compression bomb. */
-int
-tor_compress_is_compression_bomb(size_t size_in, size_t size_out)
-{
- if (size_in == 0 || size_out < CHECK_FOR_COMPRESSION_BOMB_AFTER)
- return 0;
-
- return (size_out / size_in > MAX_UNCOMPRESSION_FACTOR);
-}
-
-/** Given <b>level</b> return the memory level. The memory level is needed for
- * the various compression backends used in Tor.
- */
-int
-tor_compress_memory_level(compression_level_t level)
-{
- switch (level) {
- default:
- case HIGH_COMPRESSION: return 8;
- case MEDIUM_COMPRESSION: return 7;
- case LOW_COMPRESSION: return 6;
- }
-}
-
-/** 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_compress(char **out, size_t *out_len,
- const char *in, size_t in_len,
- compress_method_t method)
-{
- if (method == GZIP_METHOD || method == ZLIB_METHOD)
- return tor_zlib_compress(out, out_len, in, in_len, method);
-
- return -1;
-}
-
-/** Given zero or more zlib-compressed or gzip-compressed strings of
- * total length
- * <b>in_len</b> bytes at <b>in</b>, uncompress them into a newly allocated
- * buffer, using the method described in <b>method</b>. 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_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)
-{
- if (method == GZIP_METHOD || method == ZLIB_METHOD)
- return tor_zlib_uncompress(out, out_len, in, in_len,
- method,
- complete_only,
- protocol_warn_level);
-
- return -1;
-}
-
-/** Try to tell whether the <b>in_len</b>-byte string in <b>in</b> is likely
- * to be compressed or not. If it is, return the likeliest compression method.
- * Otherwise, return UNKNOWN_METHOD.
- */
-compress_method_t
-detect_compression_method(const char *in, size_t in_len)
-{
- if (in_len > 2 && fast_memeq(in, "\x1f\x8b", 2)) {
- return GZIP_METHOD;
- } else if (in_len > 2 && (in[0] & 0x0f) == 8 &&
- (ntohs(get_uint16(in)) % 31) == 0) {
- return ZLIB_METHOD;
- } else {
- return UNKNOWN_METHOD;
- }
-}
-
-/** Internal state for an incremental compression/decompression. The body of
- * this struct is not exposed. */
-struct tor_compress_state_t {
- compress_method_t method; /**< The compression method. */
-
- union {
- tor_zlib_compress_state_t *zlib_state;
- } u; /**< Compression backend state. */
-};
-
-/** Construct and return a tor_compress_state_t object using <b>method</b>. If
- * <b>compress</b>, it's for compression; otherwise it's for decompression. */
-tor_compress_state_t *
-tor_compress_new(int compress, compress_method_t method,
- compression_level_t compression_level)
-{
- tor_compress_state_t *state;
-
- state = tor_malloc_zero(sizeof(tor_compress_state_t));
- state->method = method;
-
- if (method == GZIP_METHOD || method == ZLIB_METHOD) {
- tor_zlib_compress_state_t *zlib_state =
- tor_zlib_compress_new(compress, method, compression_level);
-
- if (zlib_state == NULL)
- goto err;
-
- state->u.zlib_state = zlib_state;
- }
-
- return state;
-
- err:
- tor_free(state);
- return NULL;
-}
-
-/** Compress/decompress some bytes using <b>state</b>. Read up to
- * *<b>in_len</b> bytes from *<b>in</b>, and write up to *<b>out_len</b> bytes
- * to *<b>out</b>, adjusting the values as we go. If <b>finish</b> is true,
- * we've reached the end of the input.
- *
- * Return TOR_COMPRESS_DONE if we've finished the entire
- * compression/decompression.
- * Return TOR_COMPRESS_OK if we're processed everything from the input.
- * Return TOR_COMPRESS_BUFFER_FULL if we're out of space on <b>out</b>.
- * Return TOR_COMPRESS_ERROR if the stream is corrupt.
- */
-tor_compress_output_t
-tor_compress_process(tor_compress_state_t *state,
- char **out, size_t *out_len,
- const char **in, size_t *in_len,
- int finish)
-{
- tor_assert(state != NULL);
-
- if (state->method == GZIP_METHOD || state->method == ZLIB_METHOD)
- return tor_zlib_compress_process(state->u.zlib_state,
- out, out_len, in, in_len,
- finish);
-
- return TOR_COMPRESS_ERROR;
-}
-
-/** Deallocate <b>state</b>. */
-void
-tor_compress_free(tor_compress_state_t *state)
-{
- if (state == NULL)
- return;
-
- if (state->method == GZIP_METHOD || state->method == ZLIB_METHOD)
- tor_zlib_compress_free(state->u.zlib_state);
-
- tor_free(state);
-}
-
-/** Return the approximate number of bytes allocated for <b>state</b>. */
-size_t
-tor_compress_state_size(const tor_compress_state_t *state)
-{
- tor_assert(state != NULL);
-
- if (state->method == GZIP_METHOD || state->method == ZLIB_METHOD)
- return tor_zlib_compress_state_size(state->u.zlib_state);
-
- return 0;
-}
-