summaryrefslogtreecommitdiffstats
path: root/g10/compress.c
diff options
context:
space:
mode:
Diffstat (limited to 'g10/compress.c')
-rw-r--r--g10/compress.c377
1 files changed, 377 insertions, 0 deletions
diff --git a/g10/compress.c b/g10/compress.c
new file mode 100644
index 0000000..e7a6f2b
--- /dev/null
+++ b/g10/compress.c
@@ -0,0 +1,377 @@
+/* compress.c - compress filter
+ * Copyright (C) 1998, 1999, 2000, 2001, 2002,
+ * 2003, 2006, 2010 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+/* Note that the code in compress-bz2.c is nearly identical to the
+ code here, so if you fix a bug here, look there to see if a
+ matching bug needs to be fixed. I tried to have one set of
+ functions that could do ZIP, ZLIB, and BZIP2, but it became
+ dangerously unreadable with #ifdefs and if(algo) -dshaw */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#ifdef HAVE_ZIP
+# include <zlib.h>
+# if defined(__riscos__) && defined(USE_ZLIBRISCOS)
+# include "zlib-riscos.h"
+# endif
+#endif
+
+#include "gpg.h"
+#include "../common/util.h"
+#include "packet.h"
+#include "filter.h"
+#include "main.h"
+#include "options.h"
+
+
+#ifdef __riscos__
+#define BYTEF_CAST(a) ((Bytef *)(a))
+#else
+#define BYTEF_CAST(a) (a)
+#endif
+
+
+
+int compress_filter_bz2( void *opaque, int control,
+ IOBUF a, byte *buf, size_t *ret_len);
+
+#ifdef HAVE_ZIP
+static void
+init_compress( compress_filter_context_t *zfx, z_stream *zs )
+{
+ int rc;
+ int level;
+
+#if defined(__riscos__) && defined(USE_ZLIBRISCOS)
+ static int zlib_initialized = 0;
+
+ if (!zlib_initialized)
+ zlib_initialized = riscos_load_module("ZLib", zlib_path, 1);
+#endif
+
+ if( opt.compress_level >= 1 && opt.compress_level <= 9 )
+ level = opt.compress_level;
+ else if( opt.compress_level == -1 )
+ level = Z_DEFAULT_COMPRESSION;
+ else {
+ log_error("invalid compression level; using default level\n");
+ level = Z_DEFAULT_COMPRESSION;
+ }
+
+ if( (rc = zfx->algo == 1? deflateInit2( zs, level, Z_DEFLATED,
+ -13, 8, Z_DEFAULT_STRATEGY)
+ : deflateInit( zs, level )
+ ) != Z_OK ) {
+ log_fatal("zlib problem: %s\n", zs->msg? zs->msg :
+ rc == Z_MEM_ERROR ? "out of core" :
+ rc == Z_VERSION_ERROR ? "invalid lib version" :
+ "unknown error" );
+ }
+
+ zfx->outbufsize = 8192;
+ zfx->outbuf = xmalloc( zfx->outbufsize );
+}
+
+static int
+do_compress( compress_filter_context_t *zfx, z_stream *zs, int flush, IOBUF a )
+{
+ int rc;
+ int zrc;
+ unsigned n;
+
+ do {
+ zs->next_out = BYTEF_CAST (zfx->outbuf);
+ zs->avail_out = zfx->outbufsize;
+ if( DBG_FILTER )
+ log_debug("enter deflate: avail_in=%u, avail_out=%u, flush=%d\n",
+ (unsigned)zs->avail_in, (unsigned)zs->avail_out, flush );
+ zrc = deflate( zs, flush );
+ if( zrc == Z_STREAM_END && flush == Z_FINISH )
+ ;
+ else if( zrc != Z_OK ) {
+ if( zs->msg )
+ log_fatal("zlib deflate problem: %s\n", zs->msg );
+ else
+ log_fatal("zlib deflate problem: rc=%d\n", zrc );
+ }
+ n = zfx->outbufsize - zs->avail_out;
+ if( DBG_FILTER )
+ log_debug("leave deflate: "
+ "avail_in=%u, avail_out=%u, n=%u, zrc=%d\n",
+ (unsigned)zs->avail_in, (unsigned)zs->avail_out,
+ (unsigned)n, zrc );
+
+ if( (rc=iobuf_write( a, zfx->outbuf, n )) ) {
+ log_debug("deflate: iobuf_write failed\n");
+ return rc;
+ }
+ } while( zs->avail_in || (flush == Z_FINISH && zrc != Z_STREAM_END) );
+ return 0;
+}
+
+static void
+init_uncompress( compress_filter_context_t *zfx, z_stream *zs )
+{
+ int rc;
+
+ /****************
+ * PGP uses a windowsize of 13 bits. Using a negative value for
+ * it forces zlib not to expect a zlib header. This is a
+ * undocumented feature Peter Gutmann told me about.
+ *
+ * We must use 15 bits for the inflator because CryptoEx uses 15
+ * bits thus the output would get scrambled w/o error indication
+ * if we would use 13 bits. For the uncompressing this does not
+ * matter at all.
+ */
+ if( (rc = zfx->algo == 1? inflateInit2( zs, -15)
+ : inflateInit( zs )) != Z_OK ) {
+ log_fatal("zlib problem: %s\n", zs->msg? zs->msg :
+ rc == Z_MEM_ERROR ? "out of core" :
+ rc == Z_VERSION_ERROR ? "invalid lib version" :
+ "unknown error" );
+ }
+
+ zfx->inbufsize = 2048;
+ zfx->inbuf = xmalloc( zfx->inbufsize );
+ zs->avail_in = 0;
+}
+
+static int
+do_uncompress( compress_filter_context_t *zfx, z_stream *zs,
+ IOBUF a, size_t *ret_len )
+{
+ int zrc;
+ int rc = 0;
+ int leave = 0;
+ size_t n;
+ int nread, count;
+ int refill = !zs->avail_in;
+
+ if( DBG_FILTER )
+ log_debug("begin inflate: avail_in=%u, avail_out=%u, inbuf=%u\n",
+ (unsigned)zs->avail_in, (unsigned)zs->avail_out,
+ (unsigned)zfx->inbufsize );
+ do {
+ if( zs->avail_in < zfx->inbufsize && refill ) {
+ n = zs->avail_in;
+ if( !n )
+ zs->next_in = BYTEF_CAST (zfx->inbuf);
+ count = zfx->inbufsize - n;
+ nread = iobuf_read( a, zfx->inbuf + n, count );
+ if( nread == -1 ) nread = 0;
+ n += nread;
+ /* Algo 1 has no zlib header which requires us to give
+ * inflate an extra dummy byte to read. To be on the safe
+ * side we allow for up to 4 ff bytes. */
+ if( nread < count && zfx->algo == 1 && zfx->algo1hack < 4) {
+ *(zfx->inbuf + n) = 0xFF;
+ zfx->algo1hack++;
+ n++;
+ leave = 1;
+ }
+ zs->avail_in = n;
+ }
+ refill = 1;
+ if( DBG_FILTER )
+ log_debug("enter inflate: avail_in=%u, avail_out=%u\n",
+ (unsigned)zs->avail_in, (unsigned)zs->avail_out);
+ zrc = inflate ( zs, Z_SYNC_FLUSH );
+ if( DBG_FILTER )
+ log_debug("leave inflate: avail_in=%u, avail_out=%u, zrc=%d\n",
+ (unsigned)zs->avail_in, (unsigned)zs->avail_out, zrc);
+ if( zrc == Z_STREAM_END )
+ rc = -1; /* eof */
+ else if( zrc != Z_OK && zrc != Z_BUF_ERROR ) {
+ if( zs->msg )
+ log_fatal("zlib inflate problem: %s\n", zs->msg );
+ else
+ log_fatal("zlib inflate problem: rc=%d\n", zrc );
+ }
+ } while (zs->avail_out && zrc != Z_STREAM_END && zrc != Z_BUF_ERROR
+ && !leave);
+
+ *ret_len = zfx->outbufsize - zs->avail_out;
+ if( DBG_FILTER )
+ log_debug("do_uncompress: returning %u bytes (%u ignored)\n",
+ (unsigned int)*ret_len, (unsigned int)zs->avail_in );
+ return rc;
+}
+
+static int
+compress_filter( void *opaque, int control,
+ IOBUF a, byte *buf, size_t *ret_len)
+{
+ size_t size = *ret_len;
+ compress_filter_context_t *zfx = opaque;
+ z_stream *zs = zfx->opaque;
+ int rc=0;
+
+ if( control == IOBUFCTRL_UNDERFLOW ) {
+ if( !zfx->status ) {
+ zs = zfx->opaque = xmalloc_clear( sizeof *zs );
+ init_uncompress( zfx, zs );
+ zfx->status = 1;
+ }
+
+ zs->next_out = BYTEF_CAST (buf);
+ zs->avail_out = size;
+ zfx->outbufsize = size; /* needed only for calculation */
+ rc = do_uncompress( zfx, zs, a, ret_len );
+ }
+ else if( control == IOBUFCTRL_FLUSH ) {
+ if( !zfx->status ) {
+ PACKET pkt;
+ PKT_compressed cd;
+ if(zfx->algo != COMPRESS_ALGO_ZIP
+ && zfx->algo != COMPRESS_ALGO_ZLIB)
+ BUG();
+ memset( &cd, 0, sizeof cd );
+ cd.len = 0;
+ cd.algorithm = zfx->algo;
+ /* Fixme: We should force a new CTB here:
+ cd.new_ctb = zfx->new_ctb;
+ */
+ init_packet( &pkt );
+ pkt.pkttype = PKT_COMPRESSED;
+ pkt.pkt.compressed = &cd;
+ if( build_packet( a, &pkt ))
+ log_bug("build_packet(PKT_COMPRESSED) failed\n");
+ zs = zfx->opaque = xmalloc_clear( sizeof *zs );
+ init_compress( zfx, zs );
+ zfx->status = 2;
+ }
+
+ zs->next_in = BYTEF_CAST (buf);
+ zs->avail_in = size;
+ rc = do_compress( zfx, zs, Z_NO_FLUSH, a );
+ }
+ else if( control == IOBUFCTRL_FREE ) {
+ if( zfx->status == 1 ) {
+ inflateEnd(zs);
+ xfree(zs);
+ zfx->opaque = NULL;
+ xfree(zfx->outbuf); zfx->outbuf = NULL;
+ }
+ else if( zfx->status == 2 ) {
+ zs->next_in = BYTEF_CAST (buf);
+ zs->avail_in = 0;
+ do_compress( zfx, zs, Z_FINISH, a );
+ deflateEnd(zs);
+ xfree(zs);
+ zfx->opaque = NULL;
+ xfree(zfx->outbuf); zfx->outbuf = NULL;
+ }
+ if (zfx->release)
+ zfx->release (zfx);
+ }
+ else if( control == IOBUFCTRL_DESC )
+ mem2str (buf, "compress_filter", *ret_len);
+ return rc;
+}
+#endif /*HAVE_ZIP*/
+
+static void
+release_context (compress_filter_context_t *ctx)
+{
+ xfree(ctx->inbuf);
+ ctx->inbuf = NULL;
+ xfree(ctx->outbuf);
+ ctx->outbuf = NULL;
+ xfree (ctx);
+}
+
+/****************
+ * Handle a compressed packet
+ */
+int
+handle_compressed (ctrl_t ctrl, void *procctx, PKT_compressed *cd,
+ int (*callback)(IOBUF, void *), void *passthru )
+{
+ int rc;
+
+ if(check_compress_algo(cd->algorithm))
+ return GPG_ERR_COMPR_ALGO;
+ if(cd->algorithm) {
+ compress_filter_context_t *cfx;
+
+ cfx = xmalloc_clear (sizeof *cfx);
+ cfx->release = release_context;
+ cfx->algo = cd->algorithm;
+ if (push_compress_filter(cd->buf, cfx, cd->algorithm))
+ xfree (cfx);
+ }
+ if( callback )
+ rc = callback(cd->buf, passthru );
+ else
+ rc = proc_packets (ctrl,procctx, cd->buf);
+ cd->buf = NULL;
+ return rc;
+}
+
+gpg_error_t
+push_compress_filter(IOBUF out,compress_filter_context_t *zfx,int algo)
+{
+ return push_compress_filter2(out,zfx,algo,0);
+}
+
+
+/* Push a compress filter and return 0 if that succeeded. */
+gpg_error_t
+push_compress_filter2(IOBUF out,compress_filter_context_t *zfx,
+ int algo,int rel)
+{
+ gpg_error_t err = gpg_error (GPG_ERR_FALSE);
+
+ if(algo>=0)
+ zfx->algo=algo;
+ else
+ zfx->algo=DEFAULT_COMPRESS_ALGO;
+
+ switch(zfx->algo)
+ {
+ case COMPRESS_ALGO_NONE:
+ break;
+
+#ifdef HAVE_ZIP
+ case COMPRESS_ALGO_ZIP:
+ case COMPRESS_ALGO_ZLIB:
+ iobuf_push_filter2(out,compress_filter,zfx,rel);
+ err = 0;
+ break;
+#endif
+
+#ifdef HAVE_BZIP2
+ case COMPRESS_ALGO_BZIP2:
+ iobuf_push_filter2(out,compress_filter_bz2,zfx,rel);
+ err = 0;
+ break;
+#endif
+
+ default:
+ BUG();
+ }
+
+ return err;
+}