1 /* Declaration of functions and data types used for MD5 sum computing 2 library functions. 3 Copyright (C) 1995-2022 Free Software Foundation, Inc. 4 This file is part of the GNU C Library. 5 6 The GNU C Library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Lesser General Public 8 License as published by the Free Software Foundation; either 9 version 2.1 of the License, or (at your option) any later version. 10 11 The GNU C Library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public 17 License along with the GNU C Library; if not, see 18 <https://www.gnu.org/licenses/>. */ 19 20 #ifndef _MD5_H 21 #define _MD5_H 1 22 23 #include <stdio.h> 24 25 #if defined HAVE_LIMITS_H || defined _LIBC 26 # include <limits.h> 27 #endif 28 29 #define MD5_DIGEST_SIZE 16 30 #define MD5_BLOCK_SIZE 64 31 32 /* The following contortions are an attempt to use the C preprocessor 33 to determine an unsigned integral type that is 32 bits wide. An 34 alternative approach is to use autoconf's AC_CHECK_SIZEOF macro, but 35 doing that would require that the configure script compile and *run* 36 the resulting executable. Locally running cross-compiled executables 37 is usually not possible. */ 38 39 #ifdef _LIBC 40 # include <stdint.h> 41 typedef uint32_t md5_uint32; 42 typedef uintptr_t md5_uintptr; 43 #else 44 # define UINT_MAX_32_BITS 4294967295U 45 46 /* If UINT_MAX isn't defined, assume it's a 32-bit type. 47 This should be valid for all systems GNU cares about because 48 that doesn't include 16-bit systems, and only modern systems 49 (that certainly have <limits.h>) have 64+-bit integral types. */ 50 51 # ifndef UINT_MAX 52 # define UINT_MAX UINT_MAX_32_BITS 53 # endif 54 55 # if UINT_MAX == UINT_MAX_32_BITS 56 typedef unsigned int md5_uint32; 57 # else 58 # if USHRT_MAX == UINT_MAX_32_BITS 59 typedef unsigned short md5_uint32; 60 # else 61 # if ULONG_MAX == UINT_MAX_32_BITS 62 typedef unsigned long md5_uint32; 63 # else 64 /* The following line is intended to evoke an error. 65 Using #error is not portable enough. */ 66 "Cannot determine unsigned 32-bit data type." 67 # endif 68 # endif 69 # endif 70 /* We have to make a guess about the integer type equivalent in size 71 to pointers which should always be correct. */ 72 typedef unsigned long int md5_uintptr; 73 #endif 74 75 /* Structure to save state of computation between the single steps. */ 76 struct md5_ctx 77 { 78 md5_uint32 A; 79 md5_uint32 B; 80 md5_uint32 C; 81 md5_uint32 D; 82 83 md5_uint32 total[2]; 84 md5_uint32 buflen; 85 union 86 { 87 char buffer[128]; 88 md5_uint32 buffer32[32]; 89 }; 90 }; 91 92 /* 93 * The following three functions are build up the low level used in 94 * the functions `md5_stream' and `md5_buffer'. 95 */ 96 97 /* Initialize structure containing state of computation. 98 (RFC 1321, 3.3: Step 3) */ 99 extern void __md5_init_ctx (struct md5_ctx *ctx) __THROW; 100 101 /* Starting with the result of former calls of this function (or the 102 initialization function update the context for the next LEN bytes 103 starting at BUFFER. 104 It is necessary that LEN is a multiple of 64!!! */ 105 extern void __md5_process_block (const void *buffer, size_t len, 106 struct md5_ctx *ctx) __THROW; 107 108 /* Starting with the result of former calls of this function (or the 109 initialization function update the context for the next LEN bytes 110 starting at BUFFER. 111 It is NOT required that LEN is a multiple of 64. */ 112 extern void __md5_process_bytes (const void *buffer, size_t len, 113 struct md5_ctx *ctx) __THROW; 114 115 /* Process the remaining bytes in the buffer and put result from CTX 116 in first 16 bytes following RESBUF. The result is always in little 117 endian byte order, so that a byte-wise output yields to the wanted 118 ASCII representation of the message digest. 119 120 IMPORTANT: On some systems it is required that RESBUF is correctly 121 aligned for a 32 bits value. */ 122 extern void *__md5_finish_ctx (struct md5_ctx *ctx, void *resbuf) __THROW; 123 124 125 /* Put result from CTX in first 16 bytes following RESBUF. The result is 126 always in little endian byte order, so that a byte-wise output yields 127 to the wanted ASCII representation of the message digest. 128 129 IMPORTANT: On some systems it is required that RESBUF is correctly 130 aligned for a 32 bits value. */ 131 extern void *__md5_read_ctx (const struct md5_ctx *ctx, void *resbuf) __THROW; 132 133 134 /* Compute MD5 message digest for bytes read from STREAM. The 135 resulting message digest number will be written into the 16 bytes 136 beginning at RESBLOCK. */ 137 extern int __md5_stream (FILE *stream, void *resblock) __THROW; 138 139 /* Compute MD5 message digest for LEN bytes beginning at BUFFER. The 140 result is always in little endian byte order, so that a byte-wise 141 output yields to the wanted ASCII representation of the message 142 digest. */ 143 extern void *__md5_buffer (const char *buffer, size_t len, 144 void *resblock) __THROW; 145 146 #endif /* md5.h */ 147