...
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Commits (4)
......@@ -7,8 +7,8 @@ LIBOR_OBJECTS = address.obj backtrace.obj compat.obj container.obj di_ops.obj \
log.obj memarea.obj mempool.obj procmon.obj sandbox.obj util.obj \
util_codedigest.obj
LIBOR_CRYPTO_OBJECTS = aes.obj crypto.obj crypto_format.obj torgzip.obj tortls.obj \
crypto_curve25519.obj curve25519-donna.obj
LIBOR_CRYPTO_OBJECTS = aes.obj crypto.obj crypto_format.obj compress.obj compress_zlib.obj \
tortls.obj crypto_curve25519.obj curve25519-donna.obj
LIBOR_EVENT_OBJECTS = compat_libevent.obj
......
/* 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 compress.c
* \brief Common compression API.
**/
#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 "compress.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;
switch (method) {
case GZIP_METHOD:
case 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;
break;
}
case NO_METHOD:
case UNKNOWN_METHOD:
goto err;
}
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);
switch (state->method) {
case GZIP_METHOD:
case ZLIB_METHOD:
return tor_zlib_compress_process(state->u.zlib_state,
out, out_len, in, in_len,
finish);
case NO_METHOD:
case UNKNOWN_METHOD:
goto err;
}
err:
return TOR_COMPRESS_ERROR;
}
/** Deallocate <b>state</b>. */
void
tor_compress_free(tor_compress_state_t *state)
{
if (state == NULL)
return;
switch (state->method) {
case GZIP_METHOD:
case ZLIB_METHOD:
tor_zlib_compress_free(state->u.zlib_state);
break;
case NO_METHOD:
case UNKNOWN_METHOD:
break;
}
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);
switch (state->method) {
case GZIP_METHOD:
case ZLIB_METHOD:
return tor_zlib_compress_state_size(state->u.zlib_state);
case NO_METHOD:
case UNKNOWN_METHOD:
goto err;
}
err:
return 0;
}
......@@ -4,12 +4,12 @@
/* See LICENSE for licensing information */
/**
* \file torgzip.h
* \brief Headers for torgzip.h
* \file compress.h
* \brief Headers for compress.c
**/
#ifndef TOR_TORGZIP_H
#define TOR_TORGZIP_H
#ifndef TOR_COMPRESS_H
#define TOR_COMPRESS_H
/** Enumeration of what kind of compression to use. Only ZLIB_METHOD and
* GZIP_METHOD is guaranteed to be supported by the compress/uncompress
......@@ -38,12 +38,6 @@ tor_uncompress(char **out, size_t *out_len,
int complete_only,
int protocol_warn_level);
const char *
tor_zlib_get_version_str(void);
const char *
tor_zlib_get_header_version_str(void);
compress_method_t detect_compression_method(const char *in, size_t in_len);
int
......@@ -60,8 +54,10 @@ typedef enum {
TOR_COMPRESS_BUFFER_FULL,
TOR_COMPRESS_ERROR
} tor_compress_output_t;
/** Internal state for an incremental zlib compression/decompression. */
/** Internal state for an incremental compression/decompression. */
typedef struct tor_compress_state_t tor_compress_state_t;
tor_compress_state_t *tor_compress_new(int compress,
compress_method_t method,
compression_level_t level);
......@@ -73,7 +69,6 @@ tor_compress_output_t tor_compress_process(tor_compress_state_t *state,
void tor_compress_free(tor_compress_state_t *state);
size_t tor_compress_state_size(const tor_compress_state_t *state);
size_t tor_zlib_get_total_allocation(void);
#endif
#endif // TOR_COMPRESS_H.
/* Copyright (c) 2003, Roger Dingledine
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2017, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file compress_zlib.h
* \brief Header for compress_zlib.c
**/
#ifndef TOR_COMPRESS_ZLIB_H
#define TOR_COMPRESS_ZLIB_H
const char *
tor_zlib_get_version_str(void);
const char *
tor_zlib_get_header_version_str(void);
int
tor_zlib_compress(char **out, size_t *out_len,
const char *in, size_t in_len,
compress_method_t method);
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);
/** Internal state for an incremental zlib/gzip compression/decompression. */
typedef struct tor_zlib_compress_state_t tor_zlib_compress_state_t;
tor_zlib_compress_state_t *
tor_zlib_compress_new(int compress,
compress_method_t method,
compression_level_t compression_level);
tor_compress_output_t
tor_zlib_compress_process(tor_zlib_compress_state_t *state,
char **out, size_t *out_len,
const char **in, size_t *in_len,
int finish);
void
tor_zlib_compress_free(tor_zlib_compress_state_t *state);
size_t
tor_zlib_compress_state_size(const tor_zlib_compress_state_t *state);
size_t
tor_zlib_get_total_allocation(void);
#endif // TOR_COMPRESS_ZLIB_H.
......@@ -105,11 +105,12 @@ src/common/src_common_libor_testing_a-log.$(OBJEXT) \
LIBOR_CRYPTO_A_SRC = \
src/common/aes.c \
src/common/compress.c \
src/common/compress_zlib.c \
src/common/crypto.c \
src/common/crypto_pwbox.c \
src/common/crypto_s2k.c \
src/common/crypto_format.c \
src/common/torgzip.c \
src/common/tortls.c \
src/common/crypto_curve25519.c \
src/common/crypto_ed25519.c
......@@ -145,6 +146,8 @@ COMMONHEADERS = \
src/common/compat_openssl.h \
src/common/compat_threads.h \
src/common/compat_time.h \
src/common/compress.h \
src/common/compress_zlib.h \
src/common/confline.h \
src/common/container.h \
src/common/crypto.h \
......@@ -163,7 +166,6 @@ COMMONHEADERS = \
src/common/storagedir.h \
src/common/testsupport.h \
src/common/timers.h \
src/common/torgzip.h \
src/common/torint.h \
src/common/torlog.h \
src/common/tortls.h \
......
......@@ -69,6 +69,8 @@
#include "circuitmux.h"
#include "circuitmux_ewma.h"
#include "circuitstats.h"
#include "compress.h"
#include "compress_zlib.h"
#include "config.h"
#include "connection.h"
#include "connection_edge.h"
......@@ -99,7 +101,6 @@
#include "statefile.h"
#include "transports.h"
#include "ext_orport.h"
#include "torgzip.h"
#ifdef _WIN32
#include <shlobj.h>
#endif
......
......@@ -58,6 +58,7 @@
#include "circuitlist.h"
#include "circuituse.h"
#include "command.h"
#include "compress_zlib.h"
#include "config.h"
#include "confparse.h"
#include "connection.h"
......
......@@ -71,7 +71,7 @@
#include "tortls.h"
#include "torlog.h"
#include "container.h"
#include "torgzip.h"
#include "compress.h"
#include "address.h"
#include "compat_libevent.h"
#include "ht.h"
......
......@@ -54,6 +54,7 @@
#include "circuitbuild.h"
#include "circuitlist.h"
#include "circuituse.h"
#include "compress_zlib.h"
#include "config.h"
#include "connection.h"
#include "connection_edge.h"
......
......@@ -44,13 +44,13 @@ double fabs(double x);
#include "buffers.h"
#include "circuitlist.h"
#include "circuitstats.h"
#include "compress.h"
#include "config.h"
#include "connection_edge.h"
#include "geoip.h"
#include "rendcommon.h"
#include "rendcache.h"
#include "test.h"
#include "torgzip.h"
#include "main.h"
#include "memarea.h"
#include "onion.h"
......
......@@ -14,6 +14,7 @@
#include "connection.h"
#include "directory.h"
#include "test.h"
#include "compress.h"
#include "connection.h"
#include "rendcommon.h"
#include "rendcache.h"
......@@ -28,7 +29,6 @@
#include "networkstatus.h"
#include "geoip.h"
#include "dirserv.h"
#include "torgzip.h"
#include "dirvote.h"
#include "log_test_helpers.h"
......