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-rw-r--r--applypatch/imgpatch.c485
1 files changed, 170 insertions, 315 deletions
diff --git a/applypatch/imgpatch.c b/applypatch/imgpatch.c
index 53228174f..e3ee80ac0 100644
--- a/applypatch/imgpatch.c
+++ b/applypatch/imgpatch.c
@@ -36,329 +36,184 @@
* Return 0 on success.
*/
int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
- const char* patch_filename,
+ const Value* patch,
SinkFn sink, void* token, SHA_CTX* ctx) {
- FILE* f;
- if ((f = fopen(patch_filename, "rb")) == NULL) {
- printf("failed to open patch file\n");
- return -1;
- }
-
- unsigned char header[12];
- if (fread(header, 1, 12, f) != 12) {
- printf("failed to read patch file header\n");
- return -1;
- }
-
- // IMGDIFF1 uses CHUNK_NORMAL and CHUNK_GZIP.
- // IMGDIFF2 uses CHUNK_NORMAL, CHUNK_DEFLATE, and CHUNK_RAW.
- if (memcmp(header, "IMGDIFF", 7) != 0 ||
- (header[7] != '1' && header[7] != '2')) {
- printf("corrupt patch file header (magic number)\n");
- return -1;
- }
-
- int num_chunks = Read4(header+8);
-
- int i;
- for (i = 0; i < num_chunks; ++i) {
- // each chunk's header record starts with 4 bytes.
- unsigned char chunk[4];
- if (fread(chunk, 1, 4, f) != 4) {
- printf("failed to read chunk %d record\n", i);
- return -1;
- }
-
- int type = Read4(chunk);
-
- if (type == CHUNK_NORMAL) {
- unsigned char normal_header[24];
- if (fread(normal_header, 1, 24, f) != 24) {
- printf("failed to read chunk %d normal header data\n", i);
- return -1;
- }
-
- size_t src_start = Read8(normal_header);
- size_t src_len = Read8(normal_header+8);
- size_t patch_offset = Read8(normal_header+16);
-
- printf("CHUNK %d: normal patch offset %d\n", i, patch_offset);
-
- ApplyBSDiffPatch(old_data + src_start, src_len,
- patch_filename, patch_offset,
- sink, token, ctx);
- } else if (type == CHUNK_GZIP) {
- // This branch is basically a duplicate of the CHUNK_DEFLATE
- // branch, with a bit of extra processing for the gzip header
- // and footer. I've avoided factoring the common code out since
- // this branch will just be deleted when we drop support for
- // IMGDIFF1.
-
- // gzip chunks have an additional 64 + gzip_header_len + 8 bytes
- // in their chunk header.
- unsigned char* gzip = malloc(64);
- if (fread(gzip, 1, 64, f) != 64) {
- printf("failed to read chunk %d initial gzip header data\n",
- i);
- return -1;
- }
- size_t gzip_header_len = Read4(gzip+60);
- gzip = realloc(gzip, 64 + gzip_header_len + 8);
- if (fread(gzip+64, 1, gzip_header_len+8, f) != gzip_header_len+8) {
- printf("failed to read chunk %d remaining gzip header data\n",
- i);
- return -1;
- }
-
- size_t src_start = Read8(gzip);
- size_t src_len = Read8(gzip+8);
- size_t patch_offset = Read8(gzip+16);
-
- size_t expanded_len = Read8(gzip+24);
- size_t target_len = Read8(gzip+32);
- int gz_level = Read4(gzip+40);
- int gz_method = Read4(gzip+44);
- int gz_windowBits = Read4(gzip+48);
- int gz_memLevel = Read4(gzip+52);
- int gz_strategy = Read4(gzip+56);
-
- printf("CHUNK %d: gzip patch offset %d\n", i, patch_offset);
-
- // Decompress the source data; the chunk header tells us exactly
- // how big we expect it to be when decompressed.
-
- unsigned char* expanded_source = malloc(expanded_len);
- if (expanded_source == NULL) {
- printf("failed to allocate %d bytes for expanded_source\n",
- expanded_len);
- return -1;
- }
-
- z_stream strm;
- strm.zalloc = Z_NULL;
- strm.zfree = Z_NULL;
- strm.opaque = Z_NULL;
- strm.avail_in = src_len - (gzip_header_len + 8);
- strm.next_in = (unsigned char*)(old_data + src_start + gzip_header_len);
- strm.avail_out = expanded_len;
- strm.next_out = expanded_source;
-
- int ret;
- ret = inflateInit2(&strm, -15);
- if (ret != Z_OK) {
- printf("failed to init source inflation: %d\n", ret);
- return -1;
- }
-
- // Because we've provided enough room to accommodate the output
- // data, we expect one call to inflate() to suffice.
- ret = inflate(&strm, Z_SYNC_FLUSH);
- if (ret != Z_STREAM_END) {
- printf("source inflation returned %d\n", ret);
- return -1;
- }
- // We should have filled the output buffer exactly.
- if (strm.avail_out != 0) {
- printf("source inflation short by %d bytes\n", strm.avail_out);
+ ssize_t pos = 12;
+ char* header = patch->data;
+ if (patch->size < 12) {
+ printf("patch too short to contain header\n");
return -1;
- }
- inflateEnd(&strm);
+ }
- // Next, apply the bsdiff patch (in memory) to the uncompressed
- // data.
- unsigned char* uncompressed_target_data;
- ssize_t uncompressed_target_size;
- if (ApplyBSDiffPatchMem(expanded_source, expanded_len,
- patch_filename, patch_offset,
- &uncompressed_target_data,
- &uncompressed_target_size) != 0) {
+ // IMGDIFF2 uses CHUNK_NORMAL, CHUNK_DEFLATE, and CHUNK_RAW.
+ // (IMGDIFF1, which is no longer supported, used CHUNK_NORMAL and
+ // CHUNK_GZIP.)
+ if (memcmp(header, "IMGDIFF2", 8) != 0) {
+ printf("corrupt patch file header (magic number)\n");
return -1;
- }
-
- // Now compress the target data and append it to the output.
-
- // start with the gzip header.
- sink(gzip+64, gzip_header_len, token);
- SHA_update(ctx, gzip+64, gzip_header_len);
-
- // we're done with the expanded_source data buffer, so we'll
- // reuse that memory to receive the output of deflate.
- unsigned char* temp_data = expanded_source;
- ssize_t temp_size = expanded_len;
- if (temp_size < 32768) {
- // ... unless the buffer is too small, in which case we'll
- // allocate a fresh one.
- free(temp_data);
- temp_data = malloc(32768);
- temp_size = 32768;
- }
+ }
- // now the deflate stream
- strm.zalloc = Z_NULL;
- strm.zfree = Z_NULL;
- strm.opaque = Z_NULL;
- strm.avail_in = uncompressed_target_size;
- strm.next_in = uncompressed_target_data;
- ret = deflateInit2(&strm, gz_level, gz_method, gz_windowBits,
- gz_memLevel, gz_strategy);
- do {
- strm.avail_out = temp_size;
- strm.next_out = temp_data;
- ret = deflate(&strm, Z_FINISH);
- size_t have = temp_size - strm.avail_out;
+ int num_chunks = Read4(header+8);
- if (sink(temp_data, have, token) != have) {
- printf("failed to write %d compressed bytes to output\n",
- have);
- return -1;
+ int i;
+ for (i = 0; i < num_chunks; ++i) {
+ // each chunk's header record starts with 4 bytes.
+ if (pos + 4 > patch->size) {
+ printf("failed to read chunk %d record\n", i);
+ return -1;
}
- SHA_update(ctx, temp_data, have);
- } while (ret != Z_STREAM_END);
- deflateEnd(&strm);
-
- // lastly, the gzip footer.
- sink(gzip+64+gzip_header_len, 8, token);
- SHA_update(ctx, gzip+64+gzip_header_len, 8);
-
- free(temp_data);
- free(uncompressed_target_data);
- free(gzip);
- } else if (type == CHUNK_RAW) {
- unsigned char raw_header[4];
- if (fread(raw_header, 1, 4, f) != 4) {
- printf("failed to read chunk %d raw header data\n", i);
- return -1;
- }
-
- size_t data_len = Read4(raw_header);
-
- printf("CHUNK %d: raw data %d\n", i, data_len);
-
- unsigned char* temp = malloc(data_len);
- if (fread(temp, 1, data_len, f) != data_len) {
- printf("failed to read chunk %d raw data\n", i);
- return -1;
- }
- SHA_update(ctx, temp, data_len);
- if (sink(temp, data_len, token) != data_len) {
- printf("failed to write chunk %d raw data\n", i);
- return -1;
- }
- } else if (type == CHUNK_DEFLATE) {
- // deflate chunks have an additional 60 bytes in their chunk header.
- unsigned char deflate_header[60];
- if (fread(deflate_header, 1, 60, f) != 60) {
- printf("failed to read chunk %d deflate header data\n", i);
- return -1;
- }
-
- size_t src_start = Read8(deflate_header);
- size_t src_len = Read8(deflate_header+8);
- size_t patch_offset = Read8(deflate_header+16);
- size_t expanded_len = Read8(deflate_header+24);
- size_t target_len = Read8(deflate_header+32);
- int level = Read4(deflate_header+40);
- int method = Read4(deflate_header+44);
- int windowBits = Read4(deflate_header+48);
- int memLevel = Read4(deflate_header+52);
- int strategy = Read4(deflate_header+56);
-
- printf("CHUNK %d: deflate patch offset %d\n", i, patch_offset);
-
- // Decompress the source data; the chunk header tells us exactly
- // how big we expect it to be when decompressed.
-
- unsigned char* expanded_source = malloc(expanded_len);
- if (expanded_source == NULL) {
- printf("failed to allocate %d bytes for expanded_source\n",
- expanded_len);
- return -1;
- }
-
- z_stream strm;
- strm.zalloc = Z_NULL;
- strm.zfree = Z_NULL;
- strm.opaque = Z_NULL;
- strm.avail_in = src_len;
- strm.next_in = (unsigned char*)(old_data + src_start);
- strm.avail_out = expanded_len;
- strm.next_out = expanded_source;
-
- int ret;
- ret = inflateInit2(&strm, -15);
- if (ret != Z_OK) {
- printf("failed to init source inflation: %d\n", ret);
- return -1;
- }
-
- // Because we've provided enough room to accommodate the output
- // data, we expect one call to inflate() to suffice.
- ret = inflate(&strm, Z_SYNC_FLUSH);
- if (ret != Z_STREAM_END) {
- printf("source inflation returned %d\n", ret);
- return -1;
- }
- // We should have filled the output buffer exactly.
- if (strm.avail_out != 0) {
- printf("source inflation short by %d bytes\n", strm.avail_out);
- return -1;
- }
- inflateEnd(&strm);
-
- // Next, apply the bsdiff patch (in memory) to the uncompressed
- // data.
- unsigned char* uncompressed_target_data;
- ssize_t uncompressed_target_size;
- if (ApplyBSDiffPatchMem(expanded_source, expanded_len,
- patch_filename, patch_offset,
- &uncompressed_target_data,
- &uncompressed_target_size) != 0) {
- return -1;
- }
-
- // Now compress the target data and append it to the output.
-
- // we're done with the expanded_source data buffer, so we'll
- // reuse that memory to receive the output of deflate.
- unsigned char* temp_data = expanded_source;
- ssize_t temp_size = expanded_len;
- if (temp_size < 32768) {
- // ... unless the buffer is too small, in which case we'll
- // allocate a fresh one.
- free(temp_data);
- temp_data = malloc(32768);
- temp_size = 32768;
- }
-
- // now the deflate stream
- strm.zalloc = Z_NULL;
- strm.zfree = Z_NULL;
- strm.opaque = Z_NULL;
- strm.avail_in = uncompressed_target_size;
- strm.next_in = uncompressed_target_data;
- ret = deflateInit2(&strm, level, method, windowBits, memLevel, strategy);
- do {
- strm.avail_out = temp_size;
- strm.next_out = temp_data;
- ret = deflate(&strm, Z_FINISH);
- size_t have = temp_size - strm.avail_out;
-
- if (sink(temp_data, have, token) != have) {
- printf("failed to write %d compressed bytes to output\n",
- have);
- return -1;
+ int type = Read4(patch->data + pos);
+ pos += 4;
+
+ if (type == CHUNK_NORMAL) {
+ char* normal_header = patch->data + pos;
+ pos += 24;
+ if (pos > patch->size) {
+ printf("failed to read chunk %d normal header data\n", i);
+ return -1;
+ }
+
+ size_t src_start = Read8(normal_header);
+ size_t src_len = Read8(normal_header+8);
+ size_t patch_offset = Read8(normal_header+16);
+
+ ApplyBSDiffPatch(old_data + src_start, src_len,
+ patch, patch_offset, sink, token, ctx);
+ } else if (type == CHUNK_RAW) {
+ char* raw_header = patch->data + pos;
+ pos += 4;
+ if (pos > patch->size) {
+ printf("failed to read chunk %d raw header data\n", i);
+ return -1;
+ }
+
+ ssize_t data_len = Read4(raw_header);
+
+ if (pos + data_len > patch->size) {
+ printf("failed to read chunk %d raw data\n", i);
+ return -1;
+ }
+ SHA_update(ctx, patch->data + pos, data_len);
+ if (sink((unsigned char*)patch->data + pos,
+ data_len, token) != data_len) {
+ printf("failed to write chunk %d raw data\n", i);
+ return -1;
+ }
+ pos += data_len;
+ } else if (type == CHUNK_DEFLATE) {
+ // deflate chunks have an additional 60 bytes in their chunk header.
+ char* deflate_header = patch->data + pos;
+ pos += 60;
+ if (pos > patch->size) {
+ printf("failed to read chunk %d deflate header data\n", i);
+ return -1;
+ }
+
+ size_t src_start = Read8(deflate_header);
+ size_t src_len = Read8(deflate_header+8);
+ size_t patch_offset = Read8(deflate_header+16);
+ size_t expanded_len = Read8(deflate_header+24);
+ size_t target_len = Read8(deflate_header+32);
+ int level = Read4(deflate_header+40);
+ int method = Read4(deflate_header+44);
+ int windowBits = Read4(deflate_header+48);
+ int memLevel = Read4(deflate_header+52);
+ int strategy = Read4(deflate_header+56);
+
+ // Decompress the source data; the chunk header tells us exactly
+ // how big we expect it to be when decompressed.
+
+ unsigned char* expanded_source = malloc(expanded_len);
+ if (expanded_source == NULL) {
+ printf("failed to allocate %d bytes for expanded_source\n",
+ expanded_len);
+ return -1;
+ }
+
+ z_stream strm;
+ strm.zalloc = Z_NULL;
+ strm.zfree = Z_NULL;
+ strm.opaque = Z_NULL;
+ strm.avail_in = src_len;
+ strm.next_in = (unsigned char*)(old_data + src_start);
+ strm.avail_out = expanded_len;
+ strm.next_out = expanded_source;
+
+ int ret;
+ ret = inflateInit2(&strm, -15);
+ if (ret != Z_OK) {
+ printf("failed to init source inflation: %d\n", ret);
+ return -1;
+ }
+
+ // Because we've provided enough room to accommodate the output
+ // data, we expect one call to inflate() to suffice.
+ ret = inflate(&strm, Z_SYNC_FLUSH);
+ if (ret != Z_STREAM_END) {
+ printf("source inflation returned %d\n", ret);
+ return -1;
+ }
+ // We should have filled the output buffer exactly.
+ if (strm.avail_out != 0) {
+ printf("source inflation short by %d bytes\n", strm.avail_out);
+ return -1;
+ }
+ inflateEnd(&strm);
+
+ // Next, apply the bsdiff patch (in memory) to the uncompressed
+ // data.
+ unsigned char* uncompressed_target_data;
+ ssize_t uncompressed_target_size;
+ if (ApplyBSDiffPatchMem(expanded_source, expanded_len,
+ patch, patch_offset,
+ &uncompressed_target_data,
+ &uncompressed_target_size) != 0) {
+ return -1;
+ }
+
+ // Now compress the target data and append it to the output.
+
+ // we're done with the expanded_source data buffer, so we'll
+ // reuse that memory to receive the output of deflate.
+ unsigned char* temp_data = expanded_source;
+ ssize_t temp_size = expanded_len;
+ if (temp_size < 32768) {
+ // ... unless the buffer is too small, in which case we'll
+ // allocate a fresh one.
+ free(temp_data);
+ temp_data = malloc(32768);
+ temp_size = 32768;
+ }
+
+ // now the deflate stream
+ strm.zalloc = Z_NULL;
+ strm.zfree = Z_NULL;
+ strm.opaque = Z_NULL;
+ strm.avail_in = uncompressed_target_size;
+ strm.next_in = uncompressed_target_data;
+ ret = deflateInit2(&strm, level, method, windowBits, memLevel, strategy);
+ do {
+ strm.avail_out = temp_size;
+ strm.next_out = temp_data;
+ ret = deflate(&strm, Z_FINISH);
+ ssize_t have = temp_size - strm.avail_out;
+
+ if (sink(temp_data, have, token) != have) {
+ printf("failed to write %ld compressed bytes to output\n",
+ (long)have);
+ return -1;
+ }
+ SHA_update(ctx, temp_data, have);
+ } while (ret != Z_STREAM_END);
+ deflateEnd(&strm);
+
+ free(temp_data);
+ free(uncompressed_target_data);
+ } else {
+ printf("patch chunk %d is unknown type %d\n", i, type);
+ return -1;
}
- SHA_update(ctx, temp_data, have);
- } while (ret != Z_STREAM_END);
- deflateEnd(&strm);
-
- free(temp_data);
- free(uncompressed_target_data);
- } else {
- printf("patch chunk %d is unknown type %d\n", i, type);
- return -1;
}
- }
- return 0;
+ return 0;
}
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