#!/usr/bin/python -u
#
# p7zr library
#
# Copyright (c) 2019-2023 Hiroshi Miura <miurahr@linux.com>
# Copyright (c) 2004-2015 by Joachim Bauch, mail@joachim-bauch.de
# 7-Zip Copyright (C) 1999-2010 Igor Pavlov
# LZMA SDK Copyright (C) 1999-2010 Igor Pavlov
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
import bz2
import lzma
import struct
import sys
import zlib
from abc import ABC, abstractmethod
from enum import Enum
from typing import Any, Dict, List, Optional, Tuple, Union
import bcj
import inflate64
import pyppmd
import pyzstd
from Cryptodome.Cipher import AES
from Cryptodome.Random import get_random_bytes
from py7zr.exceptions import PasswordRequired, UnsupportedCompressionMethodError
from py7zr.helpers import Buffer, calculate_crc32, calculate_key
from py7zr.properties import (
COMPRESSION_METHOD,
FILTER_ARM,
FILTER_ARMTHUMB,
FILTER_BROTLI,
FILTER_BZIP2,
FILTER_COPY,
FILTER_CRYPTO_AES256_SHA256,
FILTER_DEFLATE,
FILTER_DEFLATE64,
FILTER_DELTA,
FILTER_IA64,
FILTER_LZMA,
FILTER_LZMA2,
FILTER_POWERPC,
FILTER_PPMD,
FILTER_SPARC,
FILTER_X86,
FILTER_ZSTD,
MAGIC_7Z,
CompressionMethod,
get_default_blocksize,
)
try:
import brotli # type: ignore # noqa
except ImportError:
try:
import brotlicffi as brotli # type: ignore # noqa
except ImportError:
brotli = None
brotli_major = 1
brotli_minor = 0
[docs]
class ISevenZipCompressor(ABC):
[docs]
@abstractmethod
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
"""
Compress data (interface)
:param data: input data
:return: output data
"""
pass
[docs]
@abstractmethod
def flush(self) -> bytes:
"""
Flush output buffer(interface)
:return: output data
"""
pass
[docs]
class ISevenZipDecompressor(ABC):
[docs]
@abstractmethod
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
"""
Decompress data (interface)
:param data: input data
:param max_length: maximum length of output data when it can respect, otherwise ignore.
:return: output data
"""
pass
[docs]
class AESCompressor(ISevenZipCompressor):
"""AES Compression(Encryption) class.
It accept pre-processing filter which may be a LZMA compression."""
AES_CBC_BLOCKSIZE = 16
def __init__(self, password: str, blocksize: Optional[int] = None) -> None:
self.cycles = 19 # as same as p7zip
self.iv = get_random_bytes(16)
self.salt = b""
self.method = CompressionMethod.CRYPT_AES256_SHA256
key = calculate_key(password.encode("utf-16LE"), self.cycles, self.salt, "sha256")
self.iv += bytes(self.AES_CBC_BLOCKSIZE - len(self.iv)) # zero padding if iv < AES_CBC_BLOCKSIZE
self.cipher = AES.new(key, AES.MODE_CBC, self.iv)
self.flushed = False
if blocksize:
self.buf = Buffer(size=blocksize + self.AES_CBC_BLOCKSIZE * 2)
else:
self.buf = Buffer(size=get_default_blocksize() + self.AES_CBC_BLOCKSIZE * 2)
def encode_filter_properties(self):
saltsize = len(self.salt)
ivsize = len(self.iv)
ivfirst = 1 # it should always 1
saltfirst = 1 if len(self.salt) > 0 else 0
firstbyte = (self.cycles + (ivfirst << 6) + (saltfirst << 7)).to_bytes(1, "little")
secondbyte = (((ivsize - 1) & 0x0F) + (((saltsize - saltfirst) << 4) & 0xF0)).to_bytes(1, "little")
properties = firstbyte + secondbyte + self.salt + self.iv
return properties
[docs]
def compress(self, data):
"""Compression + AES encryption with 16byte alignment."""
# The size is < 16 which should be only last chunk.
# From p7zip/CPP/7zip/common/FilterCoder.cpp
# /*
# AES filters need 16-bytes alignment for HARDWARE-AES instructions.
# So we call IFilter::Filter(, size), where (size != 16 * N) only for last data block.
# AES-CBC filters need data size aligned for 16-bytes.
# So the encoder can add zeros to the end of original stream.
# Some filters (BCJ and others) don't process data at the end of stream in some cases.
# So the encoder and decoder write such last bytes without change.
# */
currentlen = len(self.buf) + len(data)
# hopefully aligned and larger than block size.
if currentlen >= 16 and (currentlen & 0x0F) == 0:
self.buf.add(data)
res = self.cipher.encrypt(self.buf.view)
self.buf.reset()
elif currentlen > 16: # when not aligned
# nextpos = (currentlen // self.AES_CBC_BLOCKSIZE) * self.AES_CBC_BLOCKSIZE
nextpos = currentlen & ~0x0F
buflen = len(self.buf)
self.buf.add(data[: nextpos - buflen])
res = self.cipher.encrypt(self.buf.view)
self.buf.set(data[nextpos - buflen :])
else: # pragma: no-cover # smaller than block size, it will processed when flush()
self.buf.add(data)
res = b""
return res
[docs]
def flush(self):
if len(self.buf) > 0:
# padlen = 16 - currentlen % 16 if currentlen % 16 > 0 else 0
padlen = -len(self.buf) & 15
self.buf.add(bytes(padlen))
res = self.cipher.encrypt(self.buf.view)
self.buf.reset()
else:
res = b""
return res
[docs]
class AESDecompressor(ISevenZipDecompressor):
"""Decrypt data"""
def __init__(self, aes_properties: bytes, password: str, blocksize: Optional[int] = None) -> None:
firstbyte = aes_properties[0]
numcyclespower = firstbyte & 0x3F
if firstbyte & 0xC0 != 0:
saltsize = (firstbyte >> 7) & 1
ivsize = (firstbyte >> 6) & 1
secondbyte = aes_properties[1]
saltsize += secondbyte >> 4
ivsize += secondbyte & 0x0F
assert len(aes_properties) == 2 + saltsize + ivsize
salt = aes_properties[2 : 2 + saltsize]
iv = aes_properties[2 + saltsize : 2 + saltsize + ivsize]
assert len(salt) == saltsize
assert len(iv) == ivsize
assert numcyclespower <= 24
if ivsize < 16:
iv += bytes("\x00" * (16 - ivsize), "ascii")
key = calculate_key(password.encode("utf-16LE"), numcyclespower, salt, "sha256")
self.cipher = AES.new(key, AES.MODE_CBC, iv)
if blocksize:
self.buf = Buffer(size=blocksize + 16)
else:
self.buf = Buffer(size=get_default_blocksize() + 16)
else:
raise UnsupportedCompressionMethodError(firstbyte, "Wrong 7zAES properties")
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
currentlen = len(self.buf) + len(data)
# when aligned to 16 bytes(expected)
if len(data) > 0 and (currentlen & 0x0F) == 0:
self.buf.add(data)
temp = self.cipher.decrypt(self.buf.view)
self.buf.reset()
return temp
elif len(data) > 0: # pragma: no-cover
# nextpos = (currentlen // 16) * 16
nextpos = currentlen & ~0x0F
buflen = len(self.buf)
temp2 = data[nextpos - buflen :]
self.buf.add(data[: nextpos - buflen])
temp = self.cipher.decrypt(self.buf.view)
self.buf.set(temp2)
return temp
elif len(self.buf) == 0: # pragma: no-cover # action flush
return b""
else: # pragma: no-cover # action padding
# align = 16
# padlen = (align - offset % align) % align
# = (align - (offset & (align - 1))) & (align - 1)
# = -offset & (align -1)
# = -offset & (16 - 1) = -offset & 15
padlen = -len(self.buf) & 15
self.buf.add(bytes(padlen))
temp3 = self.cipher.decrypt(self.buf.view) # type: bytes
self.buf.reset()
return temp3
[docs]
class DeflateCompressor(ISevenZipCompressor):
def __init__(self):
self._compressor = zlib.compressobj(wbits=-15)
[docs]
def compress(self, data):
return self._compressor.compress(data)
[docs]
def flush(self):
return self._compressor.flush()
[docs]
class DeflateDecompressor(ISevenZipDecompressor):
def __init__(self):
self.flushed = False
self._decompressor = zlib.decompressobj(wbits=-15)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
if len(data) == 0:
if self.flushed:
return b""
else:
self.flushed = True
return self._decompressor.flush()
return self._decompressor.decompress(data)
[docs]
class Deflate64Compressor(ISevenZipCompressor):
def __init__(self):
self.flushed = False
if hasattr(sys, "pypy_version_info"):
self._enabled = False # compression on pypy is disabled
else:
self._compressor = inflate64.Deflater()
self._enabled = True
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
if not self._enabled:
raise UnsupportedCompressionMethodError(None, "deflate64 is disabled on pypy.")
return self._compressor.deflate(data)
[docs]
def flush(self) -> bytes:
if not self._enabled:
raise UnsupportedCompressionMethodError(None, "deflate64 is disabled on pypy.")
if self.flushed:
return b""
self.flushed = True
return self._compressor.flush()
[docs]
class Deflate64Decompressor(ISevenZipDecompressor):
def __init__(self):
self.flushed = False
if hasattr(sys, "pypy_version_info"):
self._enabled = False
else:
self._decompressor = inflate64.Inflater()
self._enabled = True
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
if not self._enabled:
raise UnsupportedCompressionMethodError(None, "deflate64 is disabled on pypy.")
if len(data) == 0:
if self.flushed:
return b""
else:
self.flushed = True
return self._decompressor.inflate(b"")
return self._decompressor.inflate(data)
[docs]
class CopyCompressor(ISevenZipCompressor):
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return bytes(data)
[docs]
def flush(self):
return b""
[docs]
class CopyDecompressor(ISevenZipDecompressor):
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return bytes(data)
[docs]
class PpmdDecompressor(ISevenZipDecompressor):
"""Decompress PPMd compressed data"""
def __init__(self, properties: bytes, blocksize: Optional[int] = None):
if not isinstance(properties, bytes):
raise UnsupportedCompressionMethodError(properties, "Unknown type of properties is passed")
if len(properties) == 5:
order, mem = struct.unpack("<BL", properties)
elif len(properties) == 7:
order, mem, _, _ = struct.unpack("<BLBB", properties)
else:
raise UnsupportedCompressionMethodError(properties, "Unknown size of properties is passed")
self.decoder = pyppmd.Ppmd7Decoder(order, mem)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length=-1) -> bytes:
if len(data) == 0 and self.decoder.needs_input:
return self.decoder.decode(b"\0", max_length)
return self.decoder.decode(data, max_length)
[docs]
class PpmdCompressor(ISevenZipCompressor):
"""Compress with PPMd compression algorithm"""
def __init__(self, properties: bytes):
order, mem = self._decode_property(properties)
self.encoder = pyppmd.Ppmd7Encoder(order, mem)
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.encoder.encode(data)
[docs]
def flush(self):
return self.encoder.flush()
def _decode_property(self, properties):
order, mem, _, _ = struct.unpack("<BLBB", properties)
return order, mem
@classmethod
def encode_filter_properties(cls, filter: Dict[str, Union[str, int]]):
order = filter.get("order", 8)
mem = filter.get("mem", 24)
if isinstance(mem, str):
if mem.isdecimal():
size = 1 << int(mem)
elif mem.lower().endswith("m") and mem[:-1].isdecimal():
size = int(mem[:-1]) << 20
elif mem.lower().endswith("k") and mem[:-1].isdecimal():
size = int(mem[:-1]) << 10
elif mem.lower().endswith("b") and mem[:-1].isdecimal():
size = int(mem[:-1])
else:
raise ValueError("Ppmd:Unsupported memory size is specified: {0}".format(mem))
elif isinstance(mem, int):
size = 1 << mem
else:
raise ValueError("Ppmd:Unsupported memory size is specified: {0}".format(mem))
properties = struct.pack("<BLBB", order, size, 0, 0)
return properties
[docs]
class BcjSparcDecoder(ISevenZipDecompressor):
def __init__(self, size: int):
self.decoder = bcj.SparcDecoder(size)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self.decoder.decode(data)
[docs]
class BcjSparcEncoder(ISevenZipCompressor):
def __init__(self):
self.encoder = bcj.SparcEncoder()
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.encoder.encode(data)
[docs]
def flush(self):
return self.encoder.flush()
[docs]
class BcjPpcDecoder(ISevenZipDecompressor):
def __init__(self, size: int):
self.decoder = bcj.PPCDecoder(size)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self.decoder.decode(data)
[docs]
class BcjPpcEncoder(ISevenZipCompressor):
def __init__(self):
self.encoder = bcj.PPCEncoder()
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.encoder.encode(data)
[docs]
def flush(self):
return self.encoder.flush()
[docs]
class BcjArmtDecoder(ISevenZipDecompressor):
def __init__(self, size: int):
self.decoder = bcj.ARMTDecoder(size)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self.decoder.decode(data)
[docs]
class BcjArmtEncoder(ISevenZipCompressor):
def __init__(self):
self.encoder = bcj.ARMTEncoder()
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.encoder.encode(data)
[docs]
def flush(self):
return self.encoder.flush()
[docs]
class BcjArmDecoder(ISevenZipDecompressor):
def __init__(self, size: int):
self.decoder = bcj.ARMDecoder(size)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self.decoder.decode(data)
[docs]
class BcjArmEncoder(ISevenZipCompressor):
def __init__(self):
self.encoder = bcj.ARMEncoder()
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.encoder.encode(data)
[docs]
def flush(self):
return self.encoder.flush()
[docs]
class BCJDecoder(ISevenZipDecompressor):
def __init__(self, size: int):
self.decoder = bcj.BCJDecoder(size)
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self.decoder.decode(data)
[docs]
class BCJEncoder(ISevenZipCompressor):
def __init__(self):
self.encoder = bcj.BCJEncoder()
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.encoder.encode(data)
[docs]
def flush(self):
return self.encoder.flush()
[docs]
class BrotliCompressor(ISevenZipCompressor):
def __init__(self, level):
if brotli is None:
raise UnsupportedCompressionMethodError(
None,
"Brotli library load error may be happened. Please check your environment have a required system library.",
)
self._compressor = brotli.Compressor(quality=level)
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self._compressor.process(data)
[docs]
def flush(self) -> bytes:
return self._compressor.flush()
[docs]
class BrotliDecompressor(ISevenZipDecompressor):
def __init__(self, properties: bytes, block_size: int):
if brotli is None:
raise UnsupportedCompressionMethodError(
None,
"Brotli library load error may be happened. Please check your environment have a required system library.",
)
if len(properties) != 3:
raise UnsupportedCompressionMethodError(properties, "Unknown size of properties are passed")
if (properties[0], properties[1]) > (brotli_major, brotli_minor):
raise UnsupportedCompressionMethodError(
properties,
"Unsupported brotli version: {}.{} our {}.{}".format(
properties[0], properties[1], brotli_major, brotli_minor
),
)
self._prefix_checked = False
self._decompressor = brotli.Decompressor()
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1):
if not self._prefix_checked:
# check first 4bytes
if data[:4] == b"\x50\x2a\x4d\x18":
raise UnsupportedCompressionMethodError(
data[:4], "Unauthorized and modified Brotli data (skipable frame) found."
)
self._prefix_checked = True
return self._decompressor.process(data)
[docs]
class ZstdCompressor(ISevenZipCompressor):
def __init__(self, level: int):
self.compressor = pyzstd.ZstdCompressor(level)
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self.compressor.compress(data)
[docs]
def flush(self) -> bytes:
return self.compressor.flush()
[docs]
class ZstdDecompressor(ISevenZipDecompressor):
def __init__(self, properties: bytes, blocksize: int):
if len(properties) not in [3, 5]:
raise UnsupportedCompressionMethodError(properties, "Zstd takes 3 or 5 bytes properties.")
if (properties[0], properties[1], 0) > pyzstd.zstd_version_info:
raise UnsupportedCompressionMethodError(properties, "Zstd version of archive is higher than us.")
self.decompressor = pyzstd.ZstdDecompressor()
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self.decompressor.decompress(data)
algorithm_class_map: Dict[int, Tuple[Any, Any]] = {
FILTER_ZSTD: (ZstdCompressor, ZstdDecompressor),
FILTER_BROTLI: (BrotliCompressor, BrotliDecompressor),
FILTER_PPMD: (PpmdCompressor, PpmdDecompressor),
FILTER_BZIP2: (bz2.BZ2Compressor, bz2.BZ2Decompressor),
FILTER_COPY: (CopyCompressor, CopyDecompressor),
FILTER_DEFLATE: (DeflateCompressor, DeflateDecompressor),
FILTER_DEFLATE64: (Deflate64Compressor, Deflate64Decompressor),
FILTER_CRYPTO_AES256_SHA256: (AESCompressor, AESDecompressor),
FILTER_X86: (BCJEncoder, BCJDecoder),
FILTER_ARM: (BcjArmEncoder, BcjArmDecoder),
FILTER_ARMTHUMB: (BcjArmtEncoder, BcjArmtDecoder),
FILTER_POWERPC: (BcjPpcEncoder, BcjPpcDecoder),
FILTER_SPARC: (BcjSparcEncoder, BcjSparcDecoder),
}
[docs]
class LZMA1Compressor(ISevenZipCompressor):
def __init__(self, filters):
self._compressor = lzma.LZMACompressor(format=lzma.FORMAT_RAW, filters=filters)
[docs]
def compress(self, data: Union[bytes, bytearray, memoryview]) -> bytes:
return self._compressor.compress(data)
[docs]
def flush(self) -> bytes:
return self._compressor.flush()
[docs]
class LZMA1Decompressor(ISevenZipDecompressor):
def __init__(self, filters, unpacksize):
self._decompressor = lzma.LZMADecompressor(format=lzma.FORMAT_RAW, filters=filters)
self.unpacksize = unpacksize
[docs]
def decompress(self, data: Union[bytes, bytearray, memoryview], max_length: int = -1) -> bytes:
return self._decompressor.decompress(data, max_length)
[docs]
class SevenZipDecompressor:
"""Main decompressor object which is properly configured and bind to each 7zip folder.
because 7zip folder can have a custom compression method"""
def __init__(
self,
coders: List[Dict[str, Any]],
packsize: int,
unpacksizes: List[int],
crc: Optional[int],
password: Optional[str] = None,
blocksize: Optional[int] = None,
) -> None:
self.input_size = packsize
self.unpacksizes = unpacksizes
self.consumed: int = 0
self.crc = crc
self.digest: int = 0
if blocksize:
self.block_size: int = blocksize
else:
self.block_size = get_default_blocksize()
if len(coders) > 4:
raise UnsupportedCompressionMethodError(
coders, "Maximum cascade of filters is 4 but got {}.".format(len(coders))
)
self.methods_map = [SupportedMethods.is_native_coder(coder) for coder in coders] # type: List[bool]
# Check if password given for encrypted archive
if SupportedMethods.needs_password(coders) and password is None:
raise PasswordRequired(coders, "Password is required for extracting given archive.")
# Check filters combination and required parameters
if len(coders) >= 2:
target_compressor = False
has_bcj = False
bcj_index = -1
for i, coder in enumerate(coders):
filter_id = SupportedMethods.get_filter_id(coder)
if SupportedMethods.is_compressor_id(filter_id) and filter_id != FILTER_LZMA2:
target_compressor = True
if filter_id in [
FILTER_X86,
FILTER_ARM,
FILTER_ARMTHUMB,
FILTER_POWERPC,
FILTER_SPARC,
]:
has_bcj = True
bcj_index = i
# hack for LZMA1+BCJ which should be native+alternative
if target_compressor and has_bcj:
self.methods_map[bcj_index] = False
break
self.chain = [] # type: List[Union[bz2.BZ2Decompressor, lzma.LZMADecompressor, ISevenZipDecompressor]]
self._unpacksizes = [] # type: List[int]
self.input_size = self.input_size
shift = 0
prev = False
for i, r in enumerate(self.methods_map):
shift += 1 if r and prev else 0
prev = r
self._unpacksizes.append(unpacksizes[i - shift])
self._unpacked = [0 for _ in range(len(self._unpacksizes))]
self.consumed = 0
self._unused = bytearray()
self._buf = bytearray()
self._pos = 0
# ---
if all(self.methods_map):
decompressor = self._get_lzma_decompressor(coders, unpacksizes[-1])
self.chain.append(decompressor)
elif not any(self.methods_map):
for i in range(len(coders)):
self.chain.append(self._get_alternative_decompressor(coders[i], unpacksizes[i], password))
elif any(self.methods_map):
for i in range(len(coders)):
if (not any(self.methods_map[:i])) and all(self.methods_map[i:]):
for j in range(i):
self.chain.append(self._get_alternative_decompressor(coders[j], unpacksizes[j], password))
self.chain.append(self._get_lzma_decompressor(coders[i:], unpacksizes[i]))
break
else:
for i in range(len(coders)):
if self.methods_map[i]:
self.chain.append(self._get_lzma_decompressor([coders[i]], unpacksizes[i]))
else:
self.chain.append(self._get_alternative_decompressor(coders[i], unpacksizes[i], password))
else:
raise UnsupportedCompressionMethodError(coders, "Combination order of methods is not supported.")
def _decompress(self, data, max_length: int):
for i, decompressor in enumerate(self.chain):
if self._unpacked[i] < self._unpacksizes[i]:
data = decompressor.decompress(data, max_length)
self._unpacked[i] += len(data)
elif len(data) == 0:
data = b""
else:
raise EOFError
return data
def _read_data(self, fp):
# read data from disk
# determine read siize
# rest_size: rest size of packed data
# unused_s: unused packed data size
# size to consume for target file is smaller one from
# rest_size - unused_s
# block_size - unused_s
rest_size = self.input_size - self.consumed
unused_s = len(self._unused)
read_size = min(rest_size - unused_s, self.block_size - unused_s)
if read_size > 0:
data = fp.read(read_size)
self.consumed += len(data)
else:
data = b""
return data
def decompress(self, fp, max_length: int = -1) -> bytes:
if max_length < 0:
data = self._read_data(fp)
res = self._buf[self._pos :] + self._decompress(self._unused + data, max_length)
self._buf = bytearray()
self._unused = bytearray()
self._pos = 0
else:
current_buf_len = len(self._buf) - self._pos
if current_buf_len >= max_length: # we already have enough data
res = self._buf[self._pos : self._pos + max_length]
self._pos += max_length
else:
data = self._read_data(fp)
if len(self._unused) > 0:
tmp = self._decompress(self._unused + data, max_length)
self._unused = bytearray()
else:
tmp = self._decompress(data, max_length)
if current_buf_len + len(tmp) <= max_length:
res = self._buf[self._pos :] + tmp
self._buf = bytearray()
self._pos = 0
else:
res = self._buf[self._pos :] + tmp[: max_length - current_buf_len]
self._buf = bytearray(tmp[max_length - current_buf_len :])
self._pos = 0
self.digest = calculate_crc32(res, self.digest)
return res
def check_crc(self):
return self.crc == self.digest
@property
def unused_size(self):
return len(self._unused)
def _get_lzma_decompressor(self, coders: List[Dict[str, Any]], unpacksize: int):
filters: List[Dict[str, Any]] = []
lzma1 = False
for coder in coders:
if coder["numinstreams"] != 1 or coder["numoutstreams"] != 1:
raise UnsupportedCompressionMethodError(coders, "Only a simple compression method is currently supported.")
if not SupportedMethods.is_native_coder(coder):
raise UnsupportedCompressionMethodError(coders, "Non python native method is requested.")
properties = coder.get("properties", None)
filter_id = SupportedMethods.get_filter_id(coder)
if filter_id == FILTER_LZMA:
lzma1 = True
if properties is not None:
filters[:0] = [lzma._decode_filter_properties(filter_id, properties)] # type: ignore
else:
filters[:0] = [{"id": filter_id}]
if lzma1:
return LZMA1Decompressor(filters, unpacksize)
else:
return lzma.LZMADecompressor(format=lzma.FORMAT_RAW, filters=filters)
def _get_alternative_decompressor(
self, coder: Dict[str, Any], unpacksize=None, password=None
) -> Union[bz2.BZ2Decompressor, lzma.LZMADecompressor, ISevenZipDecompressor]: # noqa
filter_id = SupportedMethods.get_filter_id(coder)
# Special treatment for BCJ filters
if filter_id in [
FILTER_X86,
FILTER_ARM,
FILTER_ARMTHUMB,
FILTER_POWERPC,
FILTER_SPARC,
]:
return algorithm_class_map[filter_id][1](size=unpacksize)
# Check supported?
if SupportedMethods.is_native_coder(coder):
raise UnsupportedCompressionMethodError(coder, "Unknown method code:{}".format(coder["method"]))
if filter_id not in algorithm_class_map:
raise UnsupportedCompressionMethodError(coder, "Unknown method filter_id:{}".format(filter_id))
if algorithm_class_map[filter_id][1] is None:
raise UnsupportedCompressionMethodError(
coder, "Decompression is not supported by {}.".format(SupportedMethods.get_method_name_id(filter_id))
)
#
if SupportedMethods.is_crypto_id(filter_id):
return algorithm_class_map[filter_id][1](coder["properties"], password, self.block_size)
elif SupportedMethods.need_property(filter_id):
return algorithm_class_map[filter_id][1](coder["properties"], self.block_size)
else:
return algorithm_class_map[filter_id][1]()
[docs]
class SevenZipCompressor:
"""Main compressor object to configured for each 7zip folder."""
__slots__ = [
"filters",
"chain",
"compressor",
"coders",
"methods_map",
"digest",
"packsize",
"_block_size",
"_unpacksizes",
]
def __init__(self, filters=None, password=None, blocksize: Optional[int] = None):
self.filters: List[Dict[str, Any]] = []
self.chain: List[ISevenZipCompressor] = []
self.digest = 0
self.packsize = 0
self._unpacksizes: List[int] = []
if blocksize:
self._block_size = blocksize
else:
self._block_size = get_default_blocksize()
if filters is None:
self.filters = [{"id": lzma.FILTER_LZMA2, "preset": 7 | lzma.PRESET_EXTREME}]
else:
self.filters = filters
if len(self.filters) > 4:
raise UnsupportedCompressionMethodError(
filters, "Maximum cascade of filters is 4 but got {}.".format(len(self.filters))
)
self.methods_map = [SupportedMethods.is_native_filter(filter) for filter in self.filters]
self.coders: List[Dict[str, Any]] = []
if all(self.methods_map) and SupportedMethods.is_compressor(self.filters[-1]): # all native
self._set_native_compressors_coders(self.filters)
return
#
has_lzma2 = False
for f in self.filters:
if f["id"] == FILTER_LZMA2:
has_lzma2 = True
break
if not has_lzma2:
# when specified other than lzma2, BCJ filters should be alternative
for i, f in enumerate(self.filters):
if (
f["id"] == FILTER_X86
or f["id"] == FILTER_ARM
or f["id"] == FILTER_ARMTHUMB
or f["id"] == FILTER_SPARC
or f["id"] == FILTER_POWERPC
):
self.methods_map[i] = False
#
if not any(self.methods_map): # all alternative
for f in filters:
self._set_alternate_compressors_coders(f, password)
elif SupportedMethods.is_crypto_id(self.filters[-1]["id"]) and all(self.methods_map[:-1]):
self._set_native_compressors_coders(self.filters[:-1])
self._set_alternate_compressors_coders(self.filters[-1], password)
else:
raise UnsupportedCompressionMethodError(filters, "Unknown combination of methods.")
def _set_native_compressors_coders(self, filters):
self.chain.append(LZMA1Compressor(filters))
self._unpacksizes.append(0)
for filter in filters:
self.coders.insert(0, SupportedMethods.get_coder(filter))
def _set_alternate_compressors_coders(self, alt_filter, password=None):
filter_id = alt_filter["id"]
properties = None
if filter_id not in algorithm_class_map:
raise UnsupportedCompressionMethodError(filter_id, "Unknown filter_id is given.")
elif SupportedMethods.is_crypto_id(filter_id):
compressor = algorithm_class_map[filter_id][0](password)
elif SupportedMethods.need_property(filter_id):
if filter_id == FILTER_ZSTD:
level = alt_filter.get("level", 3)
properties = struct.pack("BBBBB", pyzstd.zstd_version_info[0], pyzstd.zstd_version_info[1], level, 0, 0)
compressor = algorithm_class_map[filter_id][0](level=level)
elif filter_id == FILTER_PPMD:
properties = PpmdCompressor.encode_filter_properties(alt_filter)
compressor = algorithm_class_map[filter_id][0](properties)
elif filter_id == FILTER_BROTLI:
level = alt_filter.get("level", 11)
properties = struct.pack("BBB", brotli_major, brotli_minor, level)
compressor = algorithm_class_map[filter_id][0](level)
else:
compressor = algorithm_class_map[filter_id][0]()
if SupportedMethods.is_crypto_id(filter_id):
properties = compressor.encode_filter_properties()
self.chain.append(compressor)
self._unpacksizes.append(0)
self.coders.insert(
0,
{
"method": SupportedMethods.get_method_id(filter_id),
"properties": properties,
"numinstreams": 1,
"numoutstreams": 1,
},
)
def compress(self, fd, fp, crc=0):
data = fd.read(self._block_size)
insize = len(data)
foutsize = 0
while data:
crc = calculate_crc32(data, crc)
for i, compressor in enumerate(self.chain):
self._unpacksizes[i] += len(data)
data = compressor.compress(data)
self.packsize += len(data)
self.digest = calculate_crc32(data, self.digest)
foutsize += len(data)
fp.write(data)
data = fd.read(self._block_size)
insize += len(data)
return insize, foutsize, crc
def flush(self, fp):
data = None
for i, compressor in enumerate(self.chain):
if data:
self._unpacksizes[i] += len(data)
data = compressor.compress(data)
data += compressor.flush()
else:
data = compressor.flush()
if data is None:
return 0
self.packsize += len(data)
self.digest = calculate_crc32(data, self.digest)
fp.write(data)
return len(data)
@property
def unpacksizes(self) -> List[int]:
result: List[int] = []
shift = 0
prev = False
for i, r in enumerate(self.methods_map):
shift += 1 if r and prev else 0
prev = r
result.insert(0, self._unpacksizes[i - shift])
return result
[docs]
class MethodsType(Enum):
compressor = 0
filter = 1
crypto = 2
[docs]
class SupportedMethods:
"""Hold list of methods."""
formats: List[Dict[str, Any]] = [{"name": "7z", "magic": MAGIC_7Z}]
methods: List[Dict[str, Any]] = [
{
"id": COMPRESSION_METHOD.COPY,
"name": "COPY",
"native": False,
"need_prop": False,
"filter_id": FILTER_COPY,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.LZMA2,
"name": "LZMA2",
"native": True,
"need_prop": True,
"filter_id": FILTER_LZMA2,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.DELTA,
"name": "DELTA",
"native": True,
"need_prop": True,
"filter_id": FILTER_DELTA,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.LZMA,
"name": "LZMA",
"native": True,
"need_prop": True,
"filter_id": FILTER_LZMA,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.P7Z_BCJ,
"name": "BCJ",
"native": True,
"need_prop": False,
"filter_id": FILTER_X86,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.BCJ_PPC,
"name": "PPC",
"native": True,
"need_prop": False,
"filter_id": FILTER_POWERPC,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.BCJ_IA64,
"name": "IA64",
"native": True,
"need_prop": False,
"filter_id": FILTER_IA64,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.BCJ_ARM,
"name": "ARM",
"native": True,
"need_prop": False,
"filter_id": FILTER_ARM,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.BCJ_ARMT,
"name": "ARMT",
"native": True,
"need_prop": False,
"filter_id": FILTER_ARMTHUMB,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.BCJ_SPARC,
"name": "SPARC",
"native": True,
"need_prop": False,
"filter_id": FILTER_SPARC,
"type": MethodsType.filter,
},
{
"id": COMPRESSION_METHOD.MISC_DEFLATE,
"name": "DEFLATE",
"native": False,
"need_prop": False,
"filter_id": FILTER_DEFLATE,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.MISC_BZIP2,
"name": "BZip2",
"native": False,
"need_prop": False,
"filter_id": FILTER_BZIP2,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.MISC_ZSTD,
"name": "ZStandard",
"native": False,
"need_prop": True,
"filter_id": FILTER_ZSTD,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.PPMD,
"name": "PPMd",
"native": False,
"need_prop": True,
"filter_id": FILTER_PPMD,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.MISC_BROTLI,
"name": "Brotli",
"native": False,
"need_prop": True,
"filter_id": FILTER_BROTLI,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.MISC_DEFLATE64,
"name": "DEFLATE64",
"native": False,
"need_prop": False,
"filter_id": FILTER_DEFLATE64,
"type": MethodsType.compressor,
},
{
"id": COMPRESSION_METHOD.CRYPT_AES256_SHA256,
"name": "7zAES",
"native": False,
"need_prop": True,
"filter_id": FILTER_CRYPTO_AES256_SHA256,
"type": MethodsType.crypto,
},
]
@classmethod
def _find_method(cls, key_id, key_value):
return next((item for item in cls.methods if item[key_id] == key_value), None)
@classmethod
def get_method_name_id(cls, filter_id):
method = cls._find_method("filter_id", filter_id)
return method["name"]
@classmethod
def get_filter_id(cls, coder):
method = cls._find_method("id", coder["method"])
if method is None:
return None
return method["filter_id"]
@classmethod
def is_native_filter(cls, filter) -> bool:
method = cls._find_method("filter_id", filter["id"])
if method is None:
raise UnsupportedCompressionMethodError(filter["id"], "Unknown method id is given.")
return method["native"]
@classmethod
def is_compressor(cls, filter):
method = cls._find_method("filter_id", filter["id"])
return method["type"] == MethodsType.compressor
@classmethod
def is_compressor_id(cls, filter_id):
method = cls._find_method("filter_id", filter_id)
return method["type"] == MethodsType.compressor
@classmethod
def is_native_coder(cls, coder) -> bool:
method = cls._find_method("id", coder["method"])
if method is None:
cls.raise_unsupported_method_id(coder)
return method["native"]
@classmethod
def need_property(cls, filter_id):
method = cls._find_method("filter_id", filter_id)
if method is None:
raise UnsupportedCompressionMethodError(filter_id, "Found an sunpported filter id.")
return method["need_prop"]
@classmethod
def is_crypto_id(cls, filter_id) -> bool:
method = cls._find_method("filter_id", filter_id)
if method is None:
cls.raise_unsupported_filter_id(filter_id)
return method["type"] == MethodsType.crypto
@classmethod
def get_method_id(cls, filter_id) -> bytes:
method = cls._find_method("filter_id", filter_id)
if method is None:
cls.raise_unsupported_filter_id(filter_id)
return method["id"]
@classmethod
def get_coder(cls, filter) -> Dict[str, Any]:
method = cls.get_method_id(filter["id"])
if filter["id"] in [lzma.FILTER_LZMA1, lzma.FILTER_LZMA2, lzma.FILTER_DELTA]:
properties: Optional[bytes] = lzma._encode_filter_properties(filter) # type: ignore # noqa
else:
properties = None
return {
"method": method,
"properties": properties,
"numinstreams": 1,
"numoutstreams": 1,
}
@classmethod
def needs_password(cls, coders) -> bool:
for coder in coders:
filter_id = SupportedMethods.get_filter_id(coder)
if filter_id is None:
continue
if SupportedMethods.is_crypto_id(filter_id):
return True
return False
@classmethod
def raise_unsupported_method_id(cls, coder):
if coder["method"] == COMPRESSION_METHOD.P7Z_BCJ2:
raise UnsupportedCompressionMethodError(
coder["method"],
"BCJ2 filter is not supported by py7zr."
" Please consider to contribute to XZ/liblzma project"
" and help Python core team implementing it."
" Or please use another tool to extract it.",
)
if coder["method"] == COMPRESSION_METHOD.MISC_LZ4:
raise UnsupportedCompressionMethodError(
coder["method"], "Archive is compressed by an unsupported algorythm LZ4."
)
raise UnsupportedCompressionMethodError(
coder["method"], "Archive is compressed by an unsupported compression algorythm."
)
@classmethod
def raise_unsupported_filter_id(cls, filter_id):
raise UnsupportedCompressionMethodError(
filter_id, "Found an unsupported filter id is specified." "Please use another compression method."
)
def get_methods_names(coders_lists: List[List[dict]]) -> List[str]:
# list of known method names with a display priority order
methods_namelist = [
"LZMA2",
"LZMA",
"BZip2",
"DEFLATE",
"DEFLATE64",
"delta",
"COPY",
"PPMd",
"ZStandard",
"LZ4*",
"BCJ2*",
"BCJ",
"ARM",
"ARMT",
"IA64",
"PPC",
"SPARC",
"7zAES",
]
unsupported_methods = {
COMPRESSION_METHOD.P7Z_BCJ2: "BCJ2*",
COMPRESSION_METHOD.MISC_LZ4: "LZ4*",
}
methods_names = []
for coders in coders_lists:
for coder in coders:
for m in SupportedMethods.methods:
if coder["method"] == m["id"]:
methods_names.append(m["name"])
if coder["method"] in unsupported_methods:
methods_names.append(unsupported_methods[coder["method"]])
return list(filter(lambda x: x in methods_names, methods_namelist))
