| // Copyright 2017 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "components/crx_file/crx2_file.h" |
| |
| #include "base/base64.h" |
| #include "base/files/file_path.h" |
| #include "base/files/file_util.h" |
| #include "base/files/scoped_file.h" |
| #include "base/macros.h" |
| #include "base/memory/ptr_util.h" |
| #include "base/numerics/safe_math.h" |
| #include "base/strings/string_number_conversions.h" |
| #include "base/strings/string_util.h" |
| #include "components/crx_file/id_util.h" |
| #include "crypto/secure_hash.h" |
| #include "crypto/sha2.h" |
| #include "crypto/signature_verifier.h" |
| |
| namespace crx_file { |
| |
| namespace { |
| |
| // The current version of the crx format. |
| static const uint32_t kCurrentVersion = 2; |
| |
| // The current version of the crx diff format. |
| static const uint32_t kCurrentDiffVersion = 0; |
| |
| // The maximum size the crx parser will tolerate for a public key. |
| static const uint32_t kMaxPublicKeySize = 1 << 16; |
| |
| // The maximum size the crx parser will tolerate for a signature. |
| static const uint32_t kMaxSignatureSize = 1 << 16; |
| |
| } // namespace |
| |
| std::unique_ptr<Crx2File> Crx2File::Create(const uint32_t key_size, |
| const uint32_t signature_size, |
| Crx2File::Error* error) { |
| Crx2File::Header header; |
| memcpy(&header.magic, kCrx2FileHeaderMagic, kCrx2FileHeaderMagicSize); |
| header.version = kCurrentVersion; |
| header.key_size = key_size; |
| header.signature_size = signature_size; |
| if (HeaderIsValid(header, error)) |
| return base::WrapUnique(new Crx2File(header)); |
| return nullptr; |
| } |
| |
| Crx2File::Crx2File(const Header& header) : header_(header) {} |
| |
| bool Crx2File::HeaderIsValid(const Crx2File::Header& header, |
| Crx2File::Error* error) { |
| bool valid = false; |
| bool diffCrx = false; |
| if (!strncmp(kCrxDiffFileHeaderMagic, header.magic, sizeof(header.magic))) |
| diffCrx = true; |
| if (strncmp(kCrx2FileHeaderMagic, header.magic, sizeof(header.magic)) && |
| !diffCrx) |
| *error = kWrongMagic; |
| else if (header.version != kCurrentVersion && |
| !(diffCrx && header.version == kCurrentDiffVersion)) |
| *error = kInvalidVersion; |
| else if (header.key_size > kMaxPublicKeySize) |
| *error = kInvalidKeyTooLarge; |
| else if (header.key_size == 0) |
| *error = kInvalidKeyTooSmall; |
| else if (header.signature_size > kMaxSignatureSize) |
| *error = kInvalidSignatureTooLarge; |
| else if (header.signature_size == 0) |
| *error = kInvalidSignatureTooSmall; |
| else |
| valid = true; |
| return valid; |
| } |
| |
| } // namespace crx_file |