diff options
Diffstat (limited to 'applypatch/imgpatch.cpp')
| -rw-r--r-- | applypatch/imgpatch.cpp | 405 |
1 files changed, 200 insertions, 205 deletions
diff --git a/applypatch/imgpatch.cpp b/applypatch/imgpatch.cpp index 1c4409e36..ae6071f0e 100644 --- a/applypatch/imgpatch.cpp +++ b/applypatch/imgpatch.cpp @@ -14,32 +14,34 @@ * limitations under the License. */ -// See imgdiff.c in this directory for a description of the patch file +// See imgdiff.cpp in this directory for a description of the patch file // format. +#include <applypatch/imgpatch.h> + +#include <errno.h> #include <stdio.h> +#include <string.h> #include <sys/cdefs.h> #include <sys/stat.h> -#include <errno.h> #include <unistd.h> -#include <string.h> #include <string> #include <vector> -#include "zlib.h" -#include "openssl/sha.h" -#include "applypatch/applypatch.h" -#include "imgdiff.h" +#include <applypatch/applypatch.h> +#include <applypatch/imgdiff.h> +#include <openssl/sha.h> +#include <zlib.h> + #include "utils.h" int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size, const unsigned char* patch_data, ssize_t patch_size, SinkFn sink, void* token) { - Value patch(VAL_BLOB, std::string( - reinterpret_cast<const char*>(patch_data), patch_size)); + Value patch(VAL_BLOB, std::string(reinterpret_cast<const char*>(patch_data), patch_size)); - return ApplyImagePatch(old_data, old_size, &patch, sink, token, nullptr, nullptr); + return ApplyImagePatch(old_data, old_size, &patch, sink, token, nullptr, nullptr); } /* @@ -48,208 +50,201 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size, * file, and update the SHA context with the output data as well. * Return 0 on success. */ -int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size, - const Value* patch, - SinkFn sink, void* token, SHA_CTX* ctx, - const Value* bonus_data) { - if (patch->data.size() < 12) { - printf("patch too short to contain header\n"); - return -1; +int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size, const Value* patch, + SinkFn sink, void* token, SHA_CTX* ctx, const Value* bonus_data) { + if (patch->data.size() < 12) { + printf("patch too short to contain header\n"); + return -1; + } + + // IMGDIFF2 uses CHUNK_NORMAL, CHUNK_DEFLATE, and CHUNK_RAW. + // (IMGDIFF1, which is no longer supported, used CHUNK_NORMAL and + // CHUNK_GZIP.) + size_t pos = 12; + const char* header = &patch->data[0]; + if (memcmp(header, "IMGDIFF2", 8) != 0) { + printf("corrupt patch file header (magic number)\n"); + return -1; + } + + int num_chunks = Read4(header + 8); + + for (int i = 0; i < num_chunks; ++i) { + // each chunk's header record starts with 4 bytes. + if (pos + 4 > patch->data.size()) { + printf("failed to read chunk %d record\n", i); + return -1; } + int type = Read4(&patch->data[pos]); + pos += 4; + + if (type == CHUNK_NORMAL) { + const char* normal_header = &patch->data[pos]; + pos += 24; + if (pos > patch->data.size()) { + printf("failed to read chunk %d normal header data\n", i); + return -1; + } - // IMGDIFF2 uses CHUNK_NORMAL, CHUNK_DEFLATE, and CHUNK_RAW. - // (IMGDIFF1, which is no longer supported, used CHUNK_NORMAL and - // CHUNK_GZIP.) - size_t pos = 12; - const char* header = &patch->data[0]; - if (memcmp(header, "IMGDIFF2", 8) != 0) { - printf("corrupt patch file header (magic number)\n"); + size_t src_start = Read8(normal_header); + size_t src_len = Read8(normal_header + 8); + size_t patch_offset = Read8(normal_header + 16); + + if (src_start + src_len > static_cast<size_t>(old_size)) { + printf("source data too short\n"); return -1; - } + } + ApplyBSDiffPatch(old_data + src_start, src_len, patch, patch_offset, sink, token, ctx); + } else if (type == CHUNK_RAW) { + const char* raw_header = &patch->data[pos]; + pos += 4; + if (pos > patch->data.size()) { + printf("failed to read chunk %d raw header data\n", i); + return -1; + } - int num_chunks = Read4(header+8); + ssize_t data_len = Read4(raw_header); - for (int i = 0; i < num_chunks; ++i) { - // each chunk's header record starts with 4 bytes. - if (pos + 4 > patch->data.size()) { - printf("failed to read chunk %d record\n", i); - return -1; + if (pos + data_len > patch->data.size()) { + printf("failed to read chunk %d raw data\n", i); + return -1; + } + if (ctx) SHA1_Update(ctx, &patch->data[pos], data_len); + if (sink(reinterpret_cast<const 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. + const char* deflate_header = &patch->data[pos]; + pos += 60; + if (pos > patch->data.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); + + if (src_start + src_len > static_cast<size_t>(old_size)) { + printf("source data too short\n"); + return -1; + } + + // Decompress the source data; the chunk header tells us exactly + // how big we expect it to be when decompressed. + + // Note: expanded_len will include the bonus data size if + // the patch was constructed with bonus data. The + // deflation will come up 'bonus_size' bytes short; these + // must be appended from the bonus_data value. + size_t bonus_size = (i == 1 && bonus_data != NULL) ? bonus_data->data.size() : 0; + + std::vector<unsigned char> expanded_source(expanded_len); + + // inflate() doesn't like strm.next_out being a nullptr even with + // avail_out being zero (Z_STREAM_ERROR). + if (expanded_len != 0) { + z_stream strm; + strm.zalloc = Z_NULL; + strm.zfree = Z_NULL; + strm.opaque = Z_NULL; + strm.avail_in = src_len; + strm.next_in = const_cast<unsigned char*>(old_data + src_start); + strm.avail_out = expanded_len; + strm.next_out = expanded_source.data(); + + int ret = inflateInit2(&strm, -15); + if (ret != Z_OK) { + printf("failed to init source inflation: %d\n", ret); + return -1; } - int type = Read4(&patch->data[pos]); - pos += 4; - - if (type == CHUNK_NORMAL) { - const char* normal_header = &patch->data[pos]; - pos += 24; - if (pos > patch->data.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); - - if (src_start + src_len > static_cast<size_t>(old_size)) { - printf("source data too short\n"); - return -1; - } - ApplyBSDiffPatch(old_data + src_start, src_len, - patch, patch_offset, sink, token, ctx); - } else if (type == CHUNK_RAW) { - const char* raw_header = &patch->data[pos]; - pos += 4; - if (pos > patch->data.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->data.size()) { - printf("failed to read chunk %d raw data\n", i); - return -1; - } - if (ctx) SHA1_Update(ctx, &patch->data[pos], data_len); - if (sink(reinterpret_cast<const 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. - const char* deflate_header = &patch->data[pos]; - pos += 60; - if (pos > patch->data.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); - - if (src_start + src_len > static_cast<size_t>(old_size)) { - printf("source data too short\n"); - return -1; - } - - // Decompress the source data; the chunk header tells us exactly - // how big we expect it to be when decompressed. - - // Note: expanded_len will include the bonus data size if - // the patch was constructed with bonus data. The - // deflation will come up 'bonus_size' bytes short; these - // must be appended from the bonus_data value. - size_t bonus_size = (i == 1 && bonus_data != NULL) ? bonus_data->data.size() : 0; - - std::vector<unsigned char> expanded_source(expanded_len); - - // inflate() doesn't like strm.next_out being a nullptr even with - // avail_out being zero (Z_STREAM_ERROR). - if (expanded_len != 0) { - 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.data(); - - 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, except - // for the bonus_size. - if (strm.avail_out != bonus_size) { - printf("source inflation short by %zu bytes\n", strm.avail_out-bonus_size); - return -1; - } - inflateEnd(&strm); - - if (bonus_size) { - memcpy(expanded_source.data() + (expanded_len - bonus_size), - &bonus_data->data[0], bonus_size); - } - } - - // Next, apply the bsdiff patch (in memory) to the uncompressed - // data. - std::vector<unsigned char> uncompressed_target_data; - if (ApplyBSDiffPatchMem(expanded_source.data(), expanded_len, - patch, patch_offset, - &uncompressed_target_data) != 0) { - return -1; - } - if (uncompressed_target_data.size() != target_len) { - printf("expected target len to be %zu, but it's %zu\n", - target_len, uncompressed_target_data.size()); - 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. - if (expanded_source.size() < 32768U) { - expanded_source.resize(32768U); - } - - { - std::vector<unsigned char>& temp_data = expanded_source; - - // now the deflate stream - z_stream strm; - strm.zalloc = Z_NULL; - strm.zfree = Z_NULL; - strm.opaque = Z_NULL; - strm.avail_in = uncompressed_target_data.size(); - strm.next_in = uncompressed_target_data.data(); - int ret = deflateInit2(&strm, level, method, windowBits, memLevel, strategy); - if (ret != Z_OK) { - printf("failed to init uncompressed data deflation: %d\n", ret); - return -1; - } - do { - strm.avail_out = temp_data.size(); - strm.next_out = temp_data.data(); - ret = deflate(&strm, Z_FINISH); - ssize_t have = temp_data.size() - strm.avail_out; - - if (sink(temp_data.data(), have, token) != have) { - printf("failed to write %zd compressed bytes to output\n", - have); - return -1; - } - if (ctx) SHA1_Update(ctx, temp_data.data(), have); - } while (ret != Z_STREAM_END); - deflateEnd(&strm); - } - } else { - printf("patch chunk %d is unknown type %d\n", i, type); - 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, except + // for the bonus_size. + if (strm.avail_out != bonus_size) { + printf("source inflation short by %zu bytes\n", strm.avail_out - bonus_size); + return -1; } + inflateEnd(&strm); + + if (bonus_size) { + memcpy(expanded_source.data() + (expanded_len - bonus_size), &bonus_data->data[0], + bonus_size); + } + } + + // Next, apply the bsdiff patch (in memory) to the uncompressed data. + std::vector<unsigned char> uncompressed_target_data; + if (ApplyBSDiffPatchMem(expanded_source.data(), expanded_len, patch, patch_offset, + &uncompressed_target_data) != 0) { + return -1; + } + if (uncompressed_target_data.size() != target_len) { + printf("expected target len to be %zu, but it's %zu\n", target_len, + uncompressed_target_data.size()); + 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. + if (expanded_source.size() < 32768U) { + expanded_source.resize(32768U); + } + + { + std::vector<unsigned char>& temp_data = expanded_source; + + // now the deflate stream + z_stream strm; + strm.zalloc = Z_NULL; + strm.zfree = Z_NULL; + strm.opaque = Z_NULL; + strm.avail_in = uncompressed_target_data.size(); + strm.next_in = uncompressed_target_data.data(); + int ret = deflateInit2(&strm, level, method, windowBits, memLevel, strategy); + if (ret != Z_OK) { + printf("failed to init uncompressed data deflation: %d\n", ret); + return -1; + } + do { + strm.avail_out = temp_data.size(); + strm.next_out = temp_data.data(); + ret = deflate(&strm, Z_FINISH); + ssize_t have = temp_data.size() - strm.avail_out; + + if (sink(temp_data.data(), have, token) != have) { + printf("failed to write %zd compressed bytes to output\n", have); + return -1; + } + if (ctx) SHA1_Update(ctx, temp_data.data(), have); + } while (ret != Z_STREAM_END); + deflateEnd(&strm); + } + } else { + printf("patch chunk %d is unknown type %d\n", i, type); + return -1; } + } - return 0; + return 0; } |