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-rw-r--r--applypatch/bspatch.c252
1 files changed, 252 insertions, 0 deletions
diff --git a/applypatch/bspatch.c b/applypatch/bspatch.c
new file mode 100644
index 000000000..d5cd6174d
--- /dev/null
+++ b/applypatch/bspatch.c
@@ -0,0 +1,252 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// This file is a nearly line-for-line copy of bspatch.c from the
+// bsdiff-4.3 distribution; the primary differences being how the
+// input and output data are read and the error handling. Running
+// applypatch with the -l option will display the bsdiff license
+// notice.
+
+#include <stdio.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <bzlib.h>
+
+#include "mincrypt/sha.h"
+#include "applypatch.h"
+
+void ShowBSDiffLicense() {
+ puts("The bsdiff library used herein is:\n"
+ "\n"
+ "Copyright 2003-2005 Colin Percival\n"
+ "All rights reserved\n"
+ "\n"
+ "Redistribution and use in source and binary forms, with or without\n"
+ "modification, are permitted providing that the following conditions\n"
+ "are met:\n"
+ "1. Redistributions of source code must retain the above copyright\n"
+ " notice, this list of conditions and the following disclaimer.\n"
+ "2. Redistributions in binary form must reproduce the above copyright\n"
+ " notice, this list of conditions and the following disclaimer in the\n"
+ " documentation and/or other materials provided with the distribution.\n"
+ "\n"
+ "THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR\n"
+ "IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED\n"
+ "WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\n"
+ "ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY\n"
+ "DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\n"
+ "DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS\n"
+ "OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)\n"
+ "HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,\n"
+ "STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING\n"
+ "IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\n"
+ "POSSIBILITY OF SUCH DAMAGE.\n"
+ "\n------------------\n\n"
+ "This program uses Julian R Seward's \"libbzip2\" library, available\n"
+ "from http://www.bzip.org/.\n"
+ );
+}
+
+static off_t offtin(u_char *buf)
+{
+ off_t y;
+
+ y=buf[7]&0x7F;
+ y=y*256;y+=buf[6];
+ y=y*256;y+=buf[5];
+ y=y*256;y+=buf[4];
+ y=y*256;y+=buf[3];
+ y=y*256;y+=buf[2];
+ y=y*256;y+=buf[1];
+ y=y*256;y+=buf[0];
+
+ if(buf[7]&0x80) y=-y;
+
+ return y;
+}
+
+
+int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size,
+ const char* patch_filename, ssize_t patch_offset,
+ SinkFn sink, void* token, SHA_CTX* ctx) {
+
+ unsigned char* new_data;
+ ssize_t new_size;
+ if (ApplyBSDiffPatchMem(old_data, old_size, patch_filename, patch_offset,
+ &new_data, &new_size) != 0) {
+ return -1;
+ }
+
+ if (sink(new_data, new_size, token) < new_size) {
+ fprintf(stderr, "short write of output: %d (%s)\n", errno, strerror(errno));
+ return 1;
+ }
+ if (ctx) {
+ SHA_update(ctx, new_data, new_size);
+ }
+ free(new_data);
+
+ return 0;
+}
+
+int ApplyBSDiffPatchMem(const unsigned char* old_data, ssize_t old_size,
+ const char* patch_filename, ssize_t patch_offset,
+ unsigned char** new_data, ssize_t* new_size) {
+
+ FILE* f;
+ if ((f = fopen(patch_filename, "rb")) == NULL) {
+ fprintf(stderr, "failed to open patch file\n");
+ return 1;
+ }
+
+ // File format:
+ // 0 8 "BSDIFF40"
+ // 8 8 X
+ // 16 8 Y
+ // 24 8 sizeof(newfile)
+ // 32 X bzip2(control block)
+ // 32+X Y bzip2(diff block)
+ // 32+X+Y ??? bzip2(extra block)
+ // with control block a set of triples (x,y,z) meaning "add x bytes
+ // from oldfile to x bytes from the diff block; copy y bytes from the
+ // extra block; seek forwards in oldfile by z bytes".
+
+ fseek(f, patch_offset, SEEK_SET);
+
+ unsigned char header[32];
+ if (fread(header, 1, 32, f) < 32) {
+ fprintf(stderr, "failed to read patch file header\n");
+ return 1;
+ }
+
+ if (memcmp(header, "BSDIFF40", 8) != 0) {
+ fprintf(stderr, "corrupt bsdiff patch file header (magic number)\n");
+ return 1;
+ }
+
+ ssize_t ctrl_len, data_len;
+ ctrl_len = offtin(header+8);
+ data_len = offtin(header+16);
+ *new_size = offtin(header+24);
+
+ if (ctrl_len < 0 || data_len < 0 || *new_size < 0) {
+ fprintf(stderr, "corrupt patch file header (data lengths)\n");
+ return 1;
+ }
+
+ fclose(f);
+
+ int bzerr;
+
+#define OPEN_AT(f, bzf, offset) \
+ FILE* f; \
+ BZFILE* bzf; \
+ if ((f = fopen(patch_filename, "rb")) == NULL) { \
+ fprintf(stderr, "failed to open patch file\n"); \
+ return 1; \
+ } \
+ if (fseeko(f, offset+patch_offset, SEEK_SET)) { \
+ fprintf(stderr, "failed to seek in patch file\n"); \
+ return 1; \
+ } \
+ if ((bzf = BZ2_bzReadOpen(&bzerr, f, 0, 0, NULL, 0)) == NULL) { \
+ fprintf(stderr, "failed to bzReadOpen in patch file (%d)\n", bzerr); \
+ return 1; \
+ }
+
+ OPEN_AT(cpf, cpfbz2, 32);
+ OPEN_AT(dpf, dpfbz2, 32+ctrl_len);
+ OPEN_AT(epf, epfbz2, 32+ctrl_len+data_len);
+
+#undef OPEN_AT
+
+ *new_data = malloc(*new_size);
+ if (*new_data == NULL) {
+ fprintf(stderr, "failed to allocate %d bytes of memory for output file\n",
+ (int)*new_size);
+ return 1;
+ }
+
+ off_t oldpos = 0, newpos = 0;
+ off_t ctrl[3];
+ off_t len_read;
+ int i;
+ unsigned char buf[8];
+ while (newpos < *new_size) {
+ // Read control data
+ for (i = 0; i < 3; ++i) {
+ len_read = BZ2_bzRead(&bzerr, cpfbz2, buf, 8);
+ if (len_read < 8 || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
+ fprintf(stderr, "corrupt patch (read control)\n");
+ return 1;
+ }
+ ctrl[i] = offtin(buf);
+ }
+
+ // Sanity check
+ if (newpos + ctrl[0] > *new_size) {
+ fprintf(stderr, "corrupt patch (new file overrun)\n");
+ return 1;
+ }
+
+ // Read diff string
+ len_read = BZ2_bzRead(&bzerr, dpfbz2, *new_data + newpos, ctrl[0]);
+ if (len_read < ctrl[0] || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
+ fprintf(stderr, "corrupt patch (read diff)\n");
+ return 1;
+ }
+
+ // Add old data to diff string
+ for (i = 0; i < ctrl[0]; ++i) {
+ if ((oldpos+i >= 0) && (oldpos+i < old_size)) {
+ (*new_data)[newpos+i] += old_data[oldpos+i];
+ }
+ }
+
+ // Adjust pointers
+ newpos += ctrl[0];
+ oldpos += ctrl[0];
+
+ // Sanity check
+ if (newpos + ctrl[1] > *new_size) {
+ fprintf(stderr, "corrupt patch (new file overrun)\n");
+ return 1;
+ }
+
+ // Read extra string
+ len_read = BZ2_bzRead(&bzerr, epfbz2, *new_data + newpos, ctrl[1]);
+ if (len_read < ctrl[1] || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
+ fprintf(stderr, "corrupt patch (read extra)\n");
+ return 1;
+ }
+
+ // Adjust pointers
+ newpos += ctrl[1];
+ oldpos += ctrl[2];
+ }
+
+ BZ2_bzReadClose(&bzerr, cpfbz2);
+ BZ2_bzReadClose(&bzerr, dpfbz2);
+ BZ2_bzReadClose(&bzerr, epfbz2);
+ fclose(cpf);
+ fclose(dpf);
+ fclose(epf);
+
+ return 0;
+}