/* * Copyright (C) 2015 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. */ #ifndef LIBZIPARCHIVE_ZIPARCHIVECOMMON_H_ #define LIBZIPARCHIVE_ZIPARCHIVECOMMON_H_ #include "android-base/macros.h" #include #include // The "end of central directory" (EOCD) record. Each archive // contains exactly once such record which appears at the end of // the archive. It contains archive wide information like the // number of entries in the archive and the offset to the central // directory of the offset. struct EocdRecord { static const uint32_t kSignature = 0x06054b50; // End of central directory signature, should always be // |kSignature|. uint32_t eocd_signature; // The number of the current "disk", i.e, the "disk" that this // central directory is on. // // This implementation assumes that each archive spans a single // disk only. i.e, that disk_num == 1. uint16_t disk_num; // The disk where the central directory starts. // // This implementation assumes that each archive spans a single // disk only. i.e, that cd_start_disk == 1. uint16_t cd_start_disk; // The number of central directory records on this disk. // // This implementation assumes that each archive spans a single // disk only. i.e, that num_records_on_disk == num_records. uint16_t num_records_on_disk; // The total number of central directory records. uint16_t num_records; // The size of the central directory (in bytes). uint32_t cd_size; // The offset of the start of the central directory, relative // to the start of the file. uint32_t cd_start_offset; // Length of the central directory comment. uint16_t comment_length; private: EocdRecord() = default; DISALLOW_COPY_AND_ASSIGN(EocdRecord); } __attribute__((packed)); // A structure representing the fixed length fields for a single // record in the central directory of the archive. In addition to // the fixed length fields listed here, each central directory // record contains a variable length "file_name" and "extra_field" // whose lengths are given by |file_name_length| and |extra_field_length| // respectively. struct CentralDirectoryRecord { static const uint32_t kSignature = 0x02014b50; // The start of record signature. Must be |kSignature|. uint32_t record_signature; // Source tool version. Top byte gives source OS. uint16_t version_made_by; // Tool version. Ignored by this implementation. uint16_t version_needed; // The "general purpose bit flags" for this entry. The only // flag value that we currently check for is the "data descriptor" // flag. uint16_t gpb_flags; // The compression method for this entry, one of |kCompressStored| // and |kCompressDeflated|. uint16_t compression_method; // The file modification time and date for this entry. uint16_t last_mod_time; uint16_t last_mod_date; // The CRC-32 checksum for this entry. uint32_t crc32; // The compressed size (in bytes) of this entry. uint32_t compressed_size; // The uncompressed size (in bytes) of this entry. uint32_t uncompressed_size; // The length of the entry file name in bytes. The file name // will appear immediately after this record. uint16_t file_name_length; // The length of the extra field info (in bytes). This data // will appear immediately after the entry file name. uint16_t extra_field_length; // The length of the entry comment (in bytes). This data will // appear immediately after the extra field. uint16_t comment_length; // The start disk for this entry. Ignored by this implementation). uint16_t file_start_disk; // File attributes. Ignored by this implementation. uint16_t internal_file_attributes; // File attributes. For archives created on Unix, the top bits are the mode. uint32_t external_file_attributes; // The offset to the local file header for this entry, from the // beginning of this archive. uint32_t local_file_header_offset; private: CentralDirectoryRecord() = default; DISALLOW_COPY_AND_ASSIGN(CentralDirectoryRecord); } __attribute__((packed)); // The local file header for a given entry. This duplicates information // present in the central directory of the archive. It is an error for // the information here to be different from the central directory // information for a given entry. struct LocalFileHeader { static const uint32_t kSignature = 0x04034b50; // The local file header signature, must be |kSignature|. uint32_t lfh_signature; // Tool version. Ignored by this implementation. uint16_t version_needed; // The "general purpose bit flags" for this entry. The only // flag value that we currently check for is the "data descriptor" // flag. uint16_t gpb_flags; // The compression method for this entry, one of |kCompressStored| // and |kCompressDeflated|. uint16_t compression_method; // The file modification time and date for this entry. uint16_t last_mod_time; uint16_t last_mod_date; // The CRC-32 checksum for this entry. uint32_t crc32; // The compressed size (in bytes) of this entry. uint32_t compressed_size; // The uncompressed size (in bytes) of this entry. uint32_t uncompressed_size; // The length of the entry file name in bytes. The file name // will appear immediately after this record. uint16_t file_name_length; // The length of the extra field info (in bytes). This data // will appear immediately after the entry file name. uint16_t extra_field_length; private: LocalFileHeader() = default; DISALLOW_COPY_AND_ASSIGN(LocalFileHeader); } __attribute__((packed)); struct DataDescriptor { // The *optional* data descriptor start signature. static const uint32_t kOptSignature = 0x08074b50; // CRC-32 checksum of the entry. uint32_t crc32; // For ZIP64 format archives, the compressed and uncompressed sizes are 8 // bytes each. Also, the ZIP64 format MAY be used regardless of the size // of a file. When extracting, if the zip64 extended information extra field // is present for the file the compressed and uncompressed sizes will be 8 // byte values. // Compressed size of the entry, the field can be either 4 bytes or 8 bytes // in the zip file. uint64_t compressed_size; // Uncompressed size of the entry, the field can be either 4 bytes or 8 bytes // in the zip file. uint64_t uncompressed_size; private: DataDescriptor() = default; DISALLOW_COPY_AND_ASSIGN(DataDescriptor); }; // The zip64 end of central directory locator helps to find the zip64 EOCD. struct Zip64EocdLocator { static constexpr uint32_t kSignature = 0x07064b50; // The signature of zip64 eocd locator, must be |kSignature| uint32_t locator_signature; // The start disk of the zip64 eocd. This implementation assumes that each // archive spans a single disk only. uint32_t eocd_start_disk; // The offset offset of the zip64 end of central directory record. uint64_t zip64_eocd_offset; // The total number of disks. This implementation assumes that each archive // spans a single disk only. uint32_t num_of_disks; private: Zip64EocdLocator() = default; DISALLOW_COPY_AND_ASSIGN(Zip64EocdLocator); } __attribute__((packed)); // The optional zip64 EOCD. If one of the fields in the end of central directory // record is too small to hold required data, the field SHOULD be set to -1 // (0xFFFF or 0xFFFFFFFF) and the ZIP64 format record SHOULD be created. struct Zip64EocdRecord { static constexpr uint32_t kSignature = 0x06064b50; // The signature of zip64 eocd record, must be |kSignature| uint32_t record_signature; // Size of zip64 end of central directory record. It SHOULD be the size of the // remaining record and SHOULD NOT include the leading 12 bytes. uint64_t record_size; // The version of the tool that make this archive. uint16_t version_made_by; // Tool version needed to extract this archive. uint16_t version_needed; // Number of this disk. uint32_t disk_num; // Number of the disk with the start of the central directory. uint32_t cd_start_disk; // Total number of entries in the central directory on this disk. // This implementation assumes that each archive spans a single // disk only. i.e, that num_records_on_disk == num_records. uint64_t num_records_on_disk; // The total number of central directory records. uint64_t num_records; // The size of the central directory in bytes. uint64_t cd_size; // The offset of the start of the central directory, relative to the start of // the file. uint64_t cd_start_offset; private: Zip64EocdRecord() = default; DISALLOW_COPY_AND_ASSIGN(Zip64EocdRecord); } __attribute__((packed)); // The possible contents of the Zip64 Extended Information Extra Field. It may appear in // the 'extra' field of a central directory record or local file header. The order of // the fields in the zip64 extended information record is fixed, but the fields MUST // only appear if the corresponding local or central directory record field is set to // 0xFFFF or 0xFFFFFFFF. And this entry in the Local header MUST include BOTH original // and compressed file size fields. struct Zip64ExtendedInfo { static constexpr uint16_t kHeaderId = 0x0001; // The header tag for this 'extra' block, should be |kHeaderId|. uint16_t header_id; // The size in bytes of the remaining data (excluding the top 4 bytes). uint16_t data_size; // Size in bytes of the uncompressed file. std::optional uncompressed_file_size; // Size in bytes of the compressed file. std::optional compressed_file_size; // Local file header offset relative to the start of the zip file. std::optional local_header_offset; // This implementation assumes that each archive spans a single disk only. So // the disk_number is not used. // uint32_t disk_num; private: Zip64ExtendedInfo() = default; DISALLOW_COPY_AND_ASSIGN(Zip64ExtendedInfo); }; // mask value that signifies that the entry has a DD static const uint32_t kGPBDDFlagMask = 0x0008; // The maximum size of a central directory or a file // comment in bytes. static const uint32_t kMaxCommentLen = 65535; #endif /* LIBZIPARCHIVE_ZIPARCHIVECOMMON_H_ */