| /* |
| * Copyright (C) 2009 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. |
| */ |
| |
| // 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 <unistd.h> |
| |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| #include <android-base/logging.h> |
| #include <android-base/memory.h> |
| #include <applypatch/applypatch.h> |
| #include <applypatch/imgdiff.h> |
| #include <openssl/sha.h> |
| #include <zlib.h> |
| |
| #include "edify/expr.h" |
| #include "otautil/print_sha1.h" |
| |
| static inline int64_t Read8(const void *address) { |
| return android::base::get_unaligned<int64_t>(address); |
| } |
| |
| static inline int32_t Read4(const void *address) { |
| return android::base::get_unaligned<int32_t>(address); |
| } |
| |
| // This function is a wrapper of ApplyBSDiffPatch(). It has a custom sink function to deflate the |
| // patched data and stream the deflated data to output. |
| static bool ApplyBSDiffPatchAndStreamOutput(const uint8_t* src_data, size_t src_len, |
| const Value& patch, size_t patch_offset, |
| const char* deflate_header, SinkFn sink) { |
| size_t expected_target_length = static_cast<size_t>(Read8(deflate_header + 32)); |
| CHECK_GT(expected_target_length, 0); |
| int level = Read4(deflate_header + 40); |
| int method = Read4(deflate_header + 44); |
| int window_bits = Read4(deflate_header + 48); |
| int mem_level = Read4(deflate_header + 52); |
| int strategy = Read4(deflate_header + 56); |
| |
| // TODO(b/67849209) Remove after debugging the unit test flakiness. |
| if (android::base::GetMinimumLogSeverity() <= android::base::LogSeverity::DEBUG) { |
| LOG(DEBUG) << "zlib version " << zlibVersion(); |
| } |
| |
| z_stream strm; |
| strm.zalloc = Z_NULL; |
| strm.zfree = Z_NULL; |
| strm.opaque = Z_NULL; |
| strm.avail_in = 0; |
| strm.next_in = nullptr; |
| int ret = deflateInit2(&strm, level, method, window_bits, mem_level, strategy); |
| if (ret != Z_OK) { |
| LOG(ERROR) << "Failed to init uncompressed data deflation: " << ret; |
| return false; |
| } |
| |
| // Define a custom sink wrapper that feeds to bspatch. It deflates the available patch data on |
| // the fly and outputs the compressed data to the given sink. |
| size_t actual_target_length = 0; |
| size_t total_written = 0; |
| static constexpr size_t buffer_size = 32768; |
| SHA_CTX sha_ctx; |
| SHA1_Init(&sha_ctx); |
| auto compression_sink = [&strm, &actual_target_length, &expected_target_length, &total_written, |
| &ret, &sink, &sha_ctx](const uint8_t* data, size_t len) -> size_t { |
| // The input patch length for an update never exceeds INT_MAX. |
| strm.avail_in = len; |
| strm.next_in = data; |
| do { |
| std::vector<uint8_t> buffer(buffer_size); |
| strm.avail_out = buffer_size; |
| strm.next_out = buffer.data(); |
| if (actual_target_length + len < expected_target_length) { |
| ret = deflate(&strm, Z_NO_FLUSH); |
| } else { |
| ret = deflate(&strm, Z_FINISH); |
| } |
| if (ret != Z_OK && ret != Z_STREAM_END) { |
| LOG(ERROR) << "Failed to deflate stream: " << ret; |
| // zero length indicates an error in the sink function of bspatch(). |
| return 0; |
| } |
| |
| size_t have = buffer_size - strm.avail_out; |
| total_written += have; |
| if (sink(buffer.data(), have) != have) { |
| LOG(ERROR) << "Failed to write " << have << " compressed bytes to output."; |
| return 0; |
| } |
| } while ((strm.avail_in != 0 || strm.avail_out == 0) && ret != Z_STREAM_END); |
| |
| // TODO(b/67849209) Remove after debugging the unit test flakiness. |
| if (android::base::GetMinimumLogSeverity() <= android::base::LogSeverity::DEBUG) { |
| SHA1_Update(&sha_ctx, data, len); |
| } |
| |
| actual_target_length += len; |
| return len; |
| }; |
| |
| int bspatch_result = ApplyBSDiffPatch(src_data, src_len, patch, patch_offset, compression_sink); |
| deflateEnd(&strm); |
| |
| if (android::base::GetMinimumLogSeverity() <= android::base::LogSeverity::DEBUG) { |
| uint8_t digest[SHA_DIGEST_LENGTH]; |
| SHA1_Final(digest, &sha_ctx); |
| LOG(DEBUG) << "sha1 of " << actual_target_length << " bytes input data: " << short_sha1(digest); |
| } |
| if (bspatch_result != 0) { |
| return false; |
| } |
| |
| if (ret != Z_STREAM_END) { |
| LOG(ERROR) << "ret is expected to be Z_STREAM_END, but it's " << ret; |
| return false; |
| } |
| |
| if (expected_target_length != actual_target_length) { |
| LOG(ERROR) << "target length is expected to be " << expected_target_length << ", but it's " |
| << actual_target_length; |
| return false; |
| } |
| LOG(DEBUG) << "bspatch writes " << total_written << " bytes in total to streaming output."; |
| |
| return true; |
| } |
| |
| int ApplyImagePatch(const unsigned char* old_data, size_t old_size, const unsigned char* patch_data, |
| size_t patch_size, SinkFn sink) { |
| Value patch(Value::Type::BLOB, |
| std::string(reinterpret_cast<const char*>(patch_data), patch_size)); |
| return ApplyImagePatch(old_data, old_size, patch, sink, nullptr); |
| } |
| |
| int ApplyImagePatch(const unsigned char* old_data, size_t old_size, const Value& patch, SinkFn sink, |
| 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.) |
| const char* const patch_header = patch.data.data(); |
| if (memcmp(patch_header, "IMGDIFF2", 8) != 0) { |
| printf("corrupt patch file header (magic number)\n"); |
| return -1; |
| } |
| |
| int num_chunks = Read4(patch_header + 8); |
| size_t pos = 12; |
| 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_header + pos); |
| pos += 4; |
| |
| if (type == CHUNK_NORMAL) { |
| const char* normal_header = patch_header + 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 = static_cast<size_t>(Read8(normal_header)); |
| size_t src_len = static_cast<size_t>(Read8(normal_header + 8)); |
| size_t patch_offset = static_cast<size_t>(Read8(normal_header + 16)); |
| |
| if (src_start + src_len > old_size) { |
| printf("source data too short\n"); |
| return -1; |
| } |
| if (ApplyBSDiffPatch(old_data + src_start, src_len, patch, patch_offset, sink) != 0) { |
| printf("Failed to apply bsdiff patch.\n"); |
| return -1; |
| } |
| |
| LOG(DEBUG) << "Processed chunk type normal"; |
| } else if (type == CHUNK_RAW) { |
| const char* raw_header = patch_header + pos; |
| pos += 4; |
| if (pos > patch.data.size()) { |
| printf("failed to read chunk %d raw header data\n", i); |
| return -1; |
| } |
| |
| size_t data_len = static_cast<size_t>(Read4(raw_header)); |
| |
| if (pos + data_len > patch.data.size()) { |
| printf("failed to read chunk %d raw data\n", i); |
| return -1; |
| } |
| if (sink(reinterpret_cast<const unsigned char*>(patch_header + pos), data_len) != data_len) { |
| printf("failed to write chunk %d raw data\n", i); |
| return -1; |
| } |
| pos += data_len; |
| |
| LOG(DEBUG) << "Processed chunk type raw"; |
| } else if (type == CHUNK_DEFLATE) { |
| // deflate chunks have an additional 60 bytes in their chunk header. |
| const char* deflate_header = patch_header + 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 = static_cast<size_t>(Read8(deflate_header)); |
| size_t src_len = static_cast<size_t>(Read8(deflate_header + 8)); |
| size_t patch_offset = static_cast<size_t>(Read8(deflate_header + 16)); |
| size_t expanded_len = static_cast<size_t>(Read8(deflate_header + 24)); |
| |
| if (src_start + src_len > 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 != nullptr) ? 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 = 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; |
| } |
| |
| // 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.data(), |
| bonus_size); |
| } |
| } |
| |
| if (!ApplyBSDiffPatchAndStreamOutput(expanded_source.data(), expanded_len, patch, |
| patch_offset, deflate_header, sink)) { |
| LOG(ERROR) << "Fail to apply streaming bspatch."; |
| return -1; |
| } |
| |
| LOG(DEBUG) << "Processed chunk type deflate"; |
| } else { |
| printf("patch chunk %d is unknown type %d\n", i, type); |
| return -1; |
| } |
| } |
| |
| return 0; |
| } |