mhd_sha256.h (8932B)
1 /* SPDX-License-Identifier: LGPL-2.1-or-later OR (GPL-2.0-or-later WITH eCos-exception-2.0) */ 2 /* 3 This file is part of GNU libmicrohttpd. 4 Copyright (C) 2022-2026 Evgeny Grin (Karlson2k) 5 6 GNU libmicrohttpd 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 GNU libmicrohttpd 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 Alternatively, you can redistribute GNU libmicrohttpd and/or 17 modify it under the terms of the GNU General Public License as 18 published by the Free Software Foundation; either version 2 of 19 the License, or (at your option) any later version, together 20 with the eCos exception, as follows: 21 22 As a special exception, if other files instantiate templates or 23 use macros or inline functions from this file, or you compile this 24 file and link it with other works to produce a work based on this 25 file, this file does not by itself cause the resulting work to be 26 covered by the GNU General Public License. However the source code 27 for this file must still be made available in accordance with 28 section (3) of the GNU General Public License v2. 29 30 This exception does not invalidate any other reasons why a work 31 based on this file might be covered by the GNU General Public 32 License. 33 34 You should have received copies of the GNU Lesser General Public 35 License and the GNU General Public License along with this library; 36 if not, see <https://www.gnu.org/licenses/>. 37 */ 38 39 /** 40 * @file src/mhd2/mhd_sha256.h 41 * @brief Simple wrapper for selecting the SHA-256 implementation backend 42 * 43 * Usage: declare a context as 'struct mhd_Sha256Ctx', then call 44 * mhd_SHA256_init(), mhd_SHA256_update() (any number of times) and 45 * mhd_SHA256_finish() to get the digest. Reuse the context with 46 * mhd_SHA256_reset() or release it with mhd_SHA256_deinit(). With some 47 * backends an operation can fail; check with mhd_SHA256_has_err(). 48 * 49 * @author Karlson2k (Evgeny Grin) 50 */ 51 52 #ifndef MHD_SHA256_H 53 #define MHD_SHA256_H 1 54 55 #include "mhd_sys_options.h" 56 57 #ifndef MHD_SUPPORT_SHA256 58 # error This file must be used only when SHA-256 is enabled 59 #endif 60 61 #include "mhd_macro_concat.h" 62 63 #if defined(MHD_SHA256_GNUTLS) 64 # include "sha256_gnutls.h" 65 66 /** 67 * The hashing backend identifier for function names 68 */ 69 # define mhd_SHA256_FUNC_NAME_ID gtls 70 /** 71 * The hashing backend identifier for data names 72 */ 73 # define mhd_SHA256_DATA_NAME_ID Gtls 74 /** 75 * The hashing backend identifier for macro names 76 */ 77 # define mhd_SHA256_MACRO_NAME_ID GTLS 78 79 #elif defined(MHD_SHA256_OPENSSL) 80 # include "sha256_openssl.h" 81 82 /** 83 * The hashing backend identifier for function names 84 */ 85 # define mhd_SHA256_FUNC_NAME_ID ossl 86 /** 87 * The hashing backend identifier for data names 88 */ 89 # define mhd_SHA256_DATA_NAME_ID Ossl 90 /** 91 * The hashing backend identifier for macro names 92 */ 93 # define mhd_SHA256_MACRO_NAME_ID OSSL 94 95 #elif defined(MHD_SHA256_MBEDTLS) 96 # include "sha256_mbedtls.h" 97 98 /** 99 * The hashing backend identifier for function names 100 */ 101 # define mhd_SHA256_FUNC_NAME_ID mtls 102 /** 103 * The hashing backend identifier for data names 104 */ 105 # define mhd_SHA256_DATA_NAME_ID Mtls 106 /** 107 * The hashing backend identifier for macro names 108 */ 109 # define mhd_SHA256_MACRO_NAME_ID MTLS 110 #elif defined(MHD_SHA256_BUILTIN) 111 # include "sha256_builtin.h" 112 113 /** 114 * The hashing backend identifier for function names 115 */ 116 # define mhd_SHA256_FUNC_NAME_ID blti 117 /** 118 * The hashing backend identifier for data names 119 */ 120 # define mhd_SHA256_DATA_NAME_ID Blti 121 /** 122 * The hashing backend identifier for macro names 123 */ 124 # define mhd_SHA256_MACRO_NAME_ID BLTI 125 #else 126 # error No SHA-256 implementation enabled 127 #endif 128 129 #if mhd_SHA256_DIGEST_SIZE != 32 130 # error Wrong value of mhd_SHA256_DIGEST_SIZE 131 #endif 132 133 /** 134 * Form the name of the function specific to the selected hashing backend 135 */ 136 #define mhd_SHA256_FUNC(name_suffix) \ 137 mhd_MACRO_CONCAT3 (mhd_SHA256_,mhd_SHA256_FUNC_NAME_ID,name_suffix) 138 139 /** 140 * Form the name of the macro specific to the selected hashing backend 141 */ 142 #define mhd_SHA256_MACRO(name_suffix) \ 143 mhd_MACRO_CONCAT3 (mhd_SHA256_,mhd_SHA256_MACRO_NAME_ID,name_suffix) 144 145 /** 146 * Struct tag of the calculation context for the selected SHA-256 backend 147 */ 148 #define mhd_Sha256Ctx mhd_MACRO_CONCAT(mhd_Sha256Ctx,mhd_SHA256_DATA_NAME_ID) 149 150 151 #if 0 != mhd_SHA256_MACRO (_EXT_ERROR_FLAG) 152 /** 153 * Indicates that SHA-256 hashing or initialisation may result in an error 154 */ 155 # define mhd_SHA256_HAS_EXT_ERROR 1 156 /** 157 * 'true' if the hashing backend has reported an error 158 */ 159 # define mhd_SHA256_has_err(ctx) (!!((ctx)->ext_error)) 160 /** 161 * Get the error number reported by hashing backend (zero if no error) 162 */ 163 # define mhd_SHA256_get_err(ctx) ((int)((ctx)->ext_error)) 164 #else 165 # define mhd_SHA256_has_err(ctx) (((void) (ctx)), !!0) 166 /** 167 * Get the error number (zero if no error) 168 */ 169 # define mhd_SHA256_get_err(ctx) ((int)(0)) 170 #endif 171 172 /** 173 * Initialise the context for SHA-256 calculation. 174 * 175 * This function must not be called more than once for @a ctx without an 176 * intervening #mhd_SHA256_deinit(). 177 * 178 * Whether or not an error is reported, #mhd_SHA256_deinit() must be 179 * called for @a ctx once this function has returned. 180 * 181 * For backends that track errors (see #mhd_SHA256_has_err()), the error state 182 * is set according to the result: cleared on success, set on failure. 183 * 184 * @param ctx the calculation context 185 */ 186 #define mhd_SHA256_init(ctx) mhd_SHA256_FUNC(_init) ((ctx)) 187 188 /** 189 * Add a portion of data to the SHA-256 calculation. 190 * 191 * For backends that track errors (see #mhd_SHA256_has_err()), this does nothing 192 * if @a ctx already has a recorded error, and records an error on failure. 193 * 194 * @param ctx the calculation context 195 * @param size number of bytes in @a data, must not be 0 196 * @param data bytes to add to hash 197 */ 198 #define mhd_SHA256_update(ctx, size, data) \ 199 mhd_SHA256_FUNC(_update) ((ctx),(size),(data)) 200 201 /** 202 * Finalise the SHA-256 calculation and return the digest. 203 * 204 * For backends that track errors (see #mhd_SHA256_has_err()), this does nothing 205 * if @a ctx already has a recorded error, and may record an error on failure. 206 * 207 * @param ctx the calculation context 208 * @param[out] digest set to the hash, must be #mhd_SHA256_DIGEST_SIZE bytes 209 */ 210 #define mhd_SHA256_finish(ctx, digest) \ 211 mhd_SHA256_FUNC(_finish) ((ctx),(digest)) 212 213 /** 214 * Reset the context for a new SHA-256 calculation. 215 * 216 * This function may be called only after #mhd_SHA256_finish(). If the context 217 * is subsequently reused for a new calculation, this function must be called 218 * before starting that calculation. 219 * 220 * For backends that track errors (see #mhd_SHA256_has_err()), this does nothing 221 * if @a ctx already has a recorded error, and may record an error on failure. 222 * 223 * @param ctx the calculation context 224 */ 225 #define mhd_SHA256_reset(ctx) mhd_SHA256_FUNC(_reset) ((ctx)) 226 227 /** 228 * Finalise the SHA-256 calculation, return the digest and reset the context. 229 * 230 * For backends that track errors (see #mhd_SHA256_has_err()): if @a ctx already 231 * has a recorded error, this does nothing and the error is preserved. 232 * Otherwise, an error is recorded in @a ctx if either the finalisation or the 233 * reset fails. A recorded error is never cleared by this macro. 234 * 235 * @param ctx the calculation context 236 * @param[out] digest set to the hash, must be #mhd_SHA256_DIGEST_SIZE bytes 237 */ 238 #define mhd_SHA256_finish_reset(ctx, digest) \ 239 (mhd_SHA256_finish((ctx),(digest)), mhd_SHA256_reset((ctx))) 240 241 /** 242 * Deinitialise the SHA-256 calculation context. 243 * 244 * After calling this function, @a ctx can be reinitialised with 245 * #mhd_SHA256_init(). 246 * 247 * For backends that track errors (see #mhd_SHA256_has_err()), the recorded 248 * error state is preserved. 249 * 250 * @param ctx the calculation context 251 */ 252 #define mhd_SHA256_deinit(ctx) mhd_SHA256_FUNC(_deinit) ((ctx)) 253 254 /** 255 * Finalise the SHA-256 calculation, return the digest and deinitialise 256 * the context. 257 * 258 * For backends that track errors (see #mhd_SHA256_has_err()): if @a ctx already 259 * has a recorded error, the error is preserved. Otherwise, an error is 260 * recorded in @a ctx if the finalisation fails. 261 * 262 * @param ctx the calculation context 263 * @param[out] digest set to the hash, must be #mhd_SHA256_DIGEST_SIZE bytes 264 */ 265 #define mhd_SHA256_finish_deinit(ctx, digest) \ 266 (mhd_SHA256_finish((ctx),(digest)), mhd_SHA256_deinit((ctx))) 267 268 #if 0 == mhd_SHA256_MACRO (_DEINIT_NOOP_FLAG) 269 /** 270 * Indicates that #mhd_SHA256_deinit() is a real function that must be called. 271 */ 272 # define mhd_SHA256_HAS_DEINIT 273 #endif 274 275 276 #endif /* MHD_SHA256_H */