1 /* Declarations of functions and data types used for SHA256 and SHA224 sum 2 library functions. 3 Copyright (C) 2005-2006, 2008-2021 Free Software Foundation, Inc. 4 5 This file is free software: you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as 7 published by the Free Software Foundation; either version 2.1 of the 8 License, or (at your option) any later version. 9 10 This file is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18 #ifndef SHA256_H 19 # define SHA256_H 1 20 21 # include <stdio.h> 22 # include <stdint.h> 23 24 # if HAVE_OPENSSL_SHA256 25 # include <openssl/sha.h> 26 # endif 27 28 # ifdef __cplusplus 29 extern "C" { 30 # endif 31 32 enum { SHA224_DIGEST_SIZE = 224 / 8 }; 33 enum { SHA256_DIGEST_SIZE = 256 / 8 }; 34 35 # if HAVE_OPENSSL_SHA256 36 # define GL_OPENSSL_NAME 224 37 # include "gl_openssl.h" 38 # define GL_OPENSSL_NAME 256 39 # include "gl_openssl.h" 40 # else 41 /* Structure to save state of computation between the single steps. */ 42 struct sha256_ctx 43 { 44 uint32_t state[8]; 45 46 uint32_t total[2]; 47 size_t buflen; /* ≥ 0, ≤ 128 */ 48 uint32_t buffer[32]; /* 128 bytes; the first buflen bytes are in use */ 49 }; 50 51 /* Initialize structure containing state of computation. */ 52 extern void sha256_init_ctx (struct sha256_ctx *ctx); 53 extern void sha224_init_ctx (struct sha256_ctx *ctx); 54 55 /* Starting with the result of former calls of this function (or the 56 initialization function update the context for the next LEN bytes 57 starting at BUFFER. 58 It is necessary that LEN is a multiple of 64!!! */ 59 extern void sha256_process_block (const void *buffer, size_t len, 60 struct sha256_ctx *ctx); 61 62 /* Starting with the result of former calls of this function (or the 63 initialization function update the context for the next LEN bytes 64 starting at BUFFER. 65 It is NOT required that LEN is a multiple of 64. */ 66 extern void sha256_process_bytes (const void *buffer, size_t len, 67 struct sha256_ctx *ctx); 68 69 /* Process the remaining bytes in the buffer and put result from CTX 70 in first 32 (28) bytes following RESBUF. The result is always in little 71 endian byte order, so that a byte-wise output yields to the wanted 72 ASCII representation of the message digest. */ 73 extern void *sha256_finish_ctx (struct sha256_ctx *ctx, void *restrict resbuf); 74 extern void *sha224_finish_ctx (struct sha256_ctx *ctx, void *restrict resbuf); 75 76 77 /* Put result from CTX in first 32 (28) bytes following RESBUF. The result is 78 always in little endian byte order, so that a byte-wise output yields 79 to the wanted ASCII representation of the message digest. */ 80 extern void *sha256_read_ctx (const struct sha256_ctx *ctx, 81 void *restrict resbuf); 82 extern void *sha224_read_ctx (const struct sha256_ctx *ctx, 83 void *restrict resbuf); 84 85 86 /* Compute SHA256 (SHA224) message digest for LEN bytes beginning at BUFFER. 87 The result is always in little endian byte order, so that a byte-wise 88 output yields to the wanted ASCII representation of the message 89 digest. */ 90 extern void *sha256_buffer (const char *buffer, size_t len, 91 void *restrict resblock); 92 extern void *sha224_buffer (const char *buffer, size_t len, 93 void *restrict resblock); 94 95 # endif 96 97 /* Compute SHA256 (SHA224) message digest for bytes read from STREAM. 98 STREAM is an open file stream. Regular files are handled more efficiently. 99 The contents of STREAM from its current position to its end will be read. 100 The case that the last operation on STREAM was an 'ungetc' is not supported. 101 The resulting message digest number will be written into the 32 (28) bytes 102 beginning at RESBLOCK. */ 103 extern int sha256_stream (FILE *stream, void *resblock); 104 extern int sha224_stream (FILE *stream, void *resblock); 105 106 107 # ifdef __cplusplus 108 } 109 # endif 110 111 #endif 112 113 /* 114 * Hey Emacs! 115 * Local Variables: 116 * coding: utf-8 117 * End: 118 */