| // SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause |
| /* |
| * linux/drivers/staging/erofs/unzip_lz4.c |
| * |
| * Copyright (C) 2018 HUAWEI, Inc. |
| * http://www.huawei.com/ |
| * Created by Gao Xiang <gaoxiang25@huawei.com> |
| * |
| * Original code taken from 'linux/lib/lz4/lz4_decompress.c' |
| */ |
| |
| /* |
| * LZ4 - Fast LZ compression algorithm |
| * Copyright (C) 2011 - 2016, Yann Collet. |
| * BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php) |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * You can contact the author at : |
| * - LZ4 homepage : http://www.lz4.org |
| * - LZ4 source repository : https://github.com/lz4/lz4 |
| * |
| * Changed for kernel usage by: |
| * Sven Schmidt <4sschmid@informatik.uni-hamburg.de> |
| */ |
| #include "internal.h" |
| #include <asm/unaligned.h> |
| #include "lz4defs.h" |
| |
| /* |
| * no public solution to solve our requirement yet. |
| * see: <required buffer size for LZ4_decompress_safe_partial> |
| * https://groups.google.com/forum/#!topic/lz4c/_3kkz5N6n00 |
| */ |
| static FORCE_INLINE int customized_lz4_decompress_safe_partial( |
| const void * const source, |
| void * const dest, |
| int inputSize, |
| int outputSize) |
| { |
| /* Local Variables */ |
| const BYTE *ip = (const BYTE *) source; |
| const BYTE * const iend = ip + inputSize; |
| |
| BYTE *op = (BYTE *) dest; |
| BYTE * const oend = op + outputSize; |
| BYTE *cpy; |
| |
| static const unsigned int dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 }; |
| static const int dec64table[] = { 0, 0, 0, -1, 0, 1, 2, 3 }; |
| |
| /* Empty output buffer */ |
| if (unlikely(outputSize == 0)) |
| return ((inputSize == 1) && (*ip == 0)) ? 0 : -1; |
| |
| /* Main Loop : decode sequences */ |
| while (1) { |
| size_t length; |
| const BYTE *match; |
| size_t offset; |
| |
| /* get literal length */ |
| unsigned int const token = *ip++; |
| |
| length = token>>ML_BITS; |
| |
| if (length == RUN_MASK) { |
| unsigned int s; |
| |
| do { |
| s = *ip++; |
| length += s; |
| } while ((ip < iend - RUN_MASK) & (s == 255)); |
| |
| if (unlikely((size_t)(op + length) < (size_t)(op))) { |
| /* overflow detection */ |
| goto _output_error; |
| } |
| if (unlikely((size_t)(ip + length) < (size_t)(ip))) { |
| /* overflow detection */ |
| goto _output_error; |
| } |
| } |
| |
| /* copy literals */ |
| cpy = op + length; |
| if ((cpy > oend - WILDCOPYLENGTH) || |
| (ip + length > iend - (2 + 1 + LASTLITERALS))) { |
| if (cpy > oend) { |
| memcpy(op, ip, length = oend - op); |
| op += length; |
| break; |
| } |
| |
| if (unlikely(ip + length > iend)) { |
| /* |
| * Error : |
| * read attempt beyond |
| * end of input buffer |
| */ |
| goto _output_error; |
| } |
| |
| memcpy(op, ip, length); |
| ip += length; |
| op += length; |
| |
| if (ip > iend - 2) |
| break; |
| /* Necessarily EOF, due to parsing restrictions */ |
| /* break; */ |
| } else { |
| LZ4_wildCopy(op, ip, cpy); |
| ip += length; |
| op = cpy; |
| } |
| |
| /* get offset */ |
| offset = LZ4_readLE16(ip); |
| ip += 2; |
| match = op - offset; |
| |
| if (unlikely(match < (const BYTE *)dest)) { |
| /* Error : offset outside buffers */ |
| goto _output_error; |
| } |
| |
| /* get matchlength */ |
| length = token & ML_MASK; |
| if (length == ML_MASK) { |
| unsigned int s; |
| |
| do { |
| s = *ip++; |
| |
| if (ip > iend - LASTLITERALS) |
| goto _output_error; |
| |
| length += s; |
| } while (s == 255); |
| |
| if (unlikely((size_t)(op + length) < (size_t)op)) { |
| /* overflow detection */ |
| goto _output_error; |
| } |
| } |
| |
| length += MINMATCH; |
| |
| /* copy match within block */ |
| cpy = op + length; |
| |
| if (unlikely(cpy >= oend - WILDCOPYLENGTH)) { |
| if (cpy >= oend) { |
| while (op < oend) |
| *op++ = *match++; |
| break; |
| } |
| goto __match; |
| } |
| |
| /* costs ~1%; silence an msan warning when offset == 0 */ |
| LZ4_write32(op, (U32)offset); |
| |
| if (unlikely(offset < 8)) { |
| const int dec64 = dec64table[offset]; |
| |
| op[0] = match[0]; |
| op[1] = match[1]; |
| op[2] = match[2]; |
| op[3] = match[3]; |
| match += dec32table[offset]; |
| memcpy(op + 4, match, 4); |
| match -= dec64; |
| } else { |
| LZ4_copy8(op, match); |
| match += 8; |
| } |
| |
| op += 8; |
| |
| if (unlikely(cpy > oend - 12)) { |
| BYTE * const oCopyLimit = oend - (WILDCOPYLENGTH - 1); |
| |
| if (op < oCopyLimit) { |
| LZ4_wildCopy(op, match, oCopyLimit); |
| match += oCopyLimit - op; |
| op = oCopyLimit; |
| } |
| __match: |
| while (op < cpy) |
| *op++ = *match++; |
| } else { |
| LZ4_copy8(op, match); |
| |
| if (length > 16) |
| LZ4_wildCopy(op + 8, match + 8, cpy); |
| } |
| |
| op = cpy; /* correction */ |
| } |
| DBG_BUGON((void *)ip - source > inputSize); |
| DBG_BUGON((void *)op - dest > outputSize); |
| |
| /* Nb of output bytes decoded */ |
| return (int) ((void *)op - dest); |
| |
| /* Overflow error detected */ |
| _output_error: |
| return -ERANGE; |
| } |
| |
| int z_erofs_unzip_lz4(void *in, void *out, size_t inlen, size_t outlen) |
| { |
| int ret = customized_lz4_decompress_safe_partial(in, |
| out, inlen, outlen); |
| |
| if (ret >= 0) |
| return ret; |
| |
| /* |
| * LZ4_decompress_safe will return an error code |
| * (< 0) if decompression failed |
| */ |
| errln("%s, failed to decompress, in[%p, %zu] outlen[%p, %zu]", |
| __func__, in, inlen, out, outlen); |
| WARN_ON(1); |
| print_hex_dump(KERN_DEBUG, "raw data [in]: ", DUMP_PREFIX_OFFSET, |
| 16, 1, in, inlen, true); |
| print_hex_dump(KERN_DEBUG, "raw data [out]: ", DUMP_PREFIX_OFFSET, |
| 16, 1, out, outlen, true); |
| return -EIO; |
| } |
| |