3 * \brief Integrity checks
5 * \author Copyright (C) 1999-2006 Igor Pavlov
6 * \author Copyright (C) 2007 Lasse Collin
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
19 #ifndef LZMA_H_INTERNAL
20 # error Never include this file directly. Use <lzma.h> instead.
25 * \brief Type of the Check
27 * The .lzma format supports multiple types of Checks that are calculated
28 * from the uncompressed data (unless it is empty; then it's calculated
34 * No Check is calculated.
36 * Size of the Check field: 0 bytes
41 * CRC32 using the polynomial from the IEEE 802.3 standard
43 * Size of the Check field: 4 bytes
48 * CRC64 using the polynomial from the ECMA-182 standard
50 * Size of the Check field: 8 bytes
53 LZMA_CHECK_SHA256 = 10
57 * Size of the Check field: 32 bytes
63 * \brief Maximum valid Check ID
65 * The .lzma file format specification specifies eight Check IDs (0-15). Some
66 * of them are only reserved i.e. no actual Check algorithm has been assigned.
67 * Still liblzma accepts any of these eight IDs for future compatibility
68 * when decoding files. If a valid but unsupported Check ID is detected,
69 * liblzma indicates a warning with LZMA_UNSUPPORTED_CHECK.
73 #define LZMA_CHECK_ID_MAX 15
77 * \brief Maximum size of a Check field
79 #define LZMA_CHECK_SIZE_MAX 64
83 * \brief Test if the given Check ID is supported
85 * Returns true if the given Check ID is supported by this liblzma build.
86 * Otherwise false is returned. It is safe to call this with a value that
87 * is not in the range [0, 15]; in that case the return value is always false.
89 extern lzma_bool lzma_check_is_supported(lzma_check check)
94 * \brief Get the size of the Check field with given Check ID
96 * Although not all Check IDs have a check algorithm associated, the size of
97 * every Check is already frozen. This function returns the size (in bytes) of
98 * the Check field with the specified Check ID. The values are taken from the
99 * section 2.1.1.2 of the .lzma file format specification:
100 * { 0, 4, 4, 4, 8, 8, 8, 16, 16, 16, 32, 32, 32, 64, 64, 64 }
102 * If the argument is not in the range [0, 15], UINT32_MAX is returned.
104 extern uint32_t lzma_check_size(lzma_check check) lzma_attr_const;
108 * \brief Calculate CRC32
110 * Calculates CRC32 using the polynomial from the IEEE 802.3 standard.
112 * \param buf Pointer to the input buffer
113 * \param size Size of the input buffer
114 * \param crc Previously returned CRC value. This is used to
115 * calculate the CRC of a big buffer in smaller chunks.
116 * Set to zero when there is no previous value.
118 * \return Updated CRC value, which can be passed to this function
119 * again to continue CRC calculation.
121 extern uint32_t lzma_crc32(const uint8_t *buf, size_t size, uint32_t crc)
126 * \brief Calculate CRC64
128 * Calculates CRC64 using the polynomial from the ECMA-182 standard.
130 * This function is used similarly to lzma_crc32(). See its documentation.
132 extern uint64_t lzma_crc64(const uint8_t *buf, size_t size, uint64_t crc)
137 * SHA256 functions are currently not exported to public API.
138 * Contact the author if you think it should be.