| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * The SHA3 algorithm family |
| 4 | * |
| 5 | * (c) 2017 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of secnet. |
| 11 | * See README for full list of copyright holders. |
| 12 | * |
| 13 | * secnet is free software; you can redistribute it and/or modify it |
| 14 | * under the terms of the GNU General Public License as published by |
| 15 | * the Free Software Foundation; either version d of the License, or |
| 16 | * (at your option) any later version. |
| 17 | * |
| 18 | * secnet is distributed in the hope that it will be useful, but |
| 19 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 21 | * General Public License for more details. |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License |
| 24 | * version 3 along with secnet; if not, see |
| 25 | * https://www.gnu.org/licenses/gpl.html. |
| 26 | * |
| 27 | * This file was originally part of Catacomb, but has been automatically |
| 28 | * modified for incorporation into secnet: see `import-catacomb-crypto' |
| 29 | * for details. |
| 30 | * |
| 31 | * Catacomb is free software; you can redistribute it and/or modify |
| 32 | * it under the terms of the GNU Library General Public License as |
| 33 | * published by the Free Software Foundation; either version 2 of the |
| 34 | * License, or (at your option) any later version. |
| 35 | * |
| 36 | * Catacomb is distributed in the hope that it will be useful, |
| 37 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 38 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 39 | * GNU Library General Public License for more details. |
| 40 | * |
| 41 | * You should have received a copy of the GNU Library General Public |
| 42 | * License along with Catacomb; if not, write to the Free |
| 43 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 44 | * MA 02111-1307, USA. |
| 45 | */ |
| 46 | |
| 47 | #ifndef CATACOMB_SHA3_H |
| 48 | #define CATACOMB_SHA3_H |
| 49 | |
| 50 | #ifdef __cplusplus |
| 51 | extern "C" { |
| 52 | #endif |
| 53 | |
| 54 | /*----- Notes on the SHA3 algorithm family --------------------------------* |
| 55 | * |
| 56 | * The winner of the SHA3 competition was Keccak, designed by Guido Bertoni, |
| 57 | * Joan Daemen, Michaƫl Peeters, and Gilles Van Assche. The algorithm uses |
| 58 | * their `sponge construction', based on a fixed attempt to instantiate an |
| 59 | * `ideal permutation'. The construction is rather versatile, and NIST has |
| 60 | * standardized a number of algorithms based on it. |
| 61 | * |
| 62 | * The basic offerings are the drop-in replacements for the SHA2 family. |
| 63 | * These are slower than is ideal, because of the decision to provide O(2^n) |
| 64 | * resistance to second-preimage attacks for the n-bit hash function, which |
| 65 | * means that, effectively, the capacity parameter is set unnecessarily |
| 66 | * large. (There was a major fuss when NIST tried to change this in a draft |
| 67 | * of te standard.) All of the obvious hash modes, e.g., HMAC, MGF, can be |
| 68 | * applied to the SHA3 hash functions, though I can't really recommend this: |
| 69 | * there's almost certainly a better way of doing whatever it is. |
| 70 | * |
| 71 | * Other members of the family are: SHAKE and cSHAKE, `extendable-output |
| 72 | * funnctions' which can be used directly in place of MGFs; and KMAC, a |
| 73 | * message authentication code with arbitrary-length key, message, and tag, |
| 74 | * which can therefore be used as a key-derivation function. The cSHAKE |
| 75 | * construction, on which KMAC is based, introduces a personalization string |
| 76 | * which can be used for domain separation. |
| 77 | */ |
| 78 | |
| 79 | /*----- Header files ------------------------------------------------------*/ |
| 80 | |
| 81 | #include "fake-mLib-bits.h" |
| 82 | |
| 83 | #ifndef CATACOMB_KECCAK1600_H |
| 84 | # include "keccak1600.h" |
| 85 | #endif |
| 86 | |
| 87 | /*----- The SHA3 hash function family -------------------------------------*/ |
| 88 | |
| 89 | typedef struct sha3_ctx { |
| 90 | keccak1600_state s; |
| 91 | unsigned r, w, n; |
| 92 | octet buf[200]; |
| 93 | } sha3_ctx; |
| 94 | #define sha3_224_ctx sha3_ctx |
| 95 | #define sha3_256_ctx sha3_ctx |
| 96 | #define sha3_384_ctx sha3_ctx |
| 97 | #define sha3_512_ctx sha3_ctx |
| 98 | |
| 99 | #define SHA3_224_HASHSZ 28 |
| 100 | #define SHA3_256_HASHSZ 32 |
| 101 | #define SHA3_384_HASHSZ 48 |
| 102 | #define SHA3_512_HASHSZ 64 |
| 103 | |
| 104 | #define SHA3_224_BUFSZ 144 |
| 105 | #define SHA3_256_BUFSZ 136 |
| 106 | #define SHA3_384_BUFSZ 104 |
| 107 | #define SHA3_512_BUFSZ 72 |
| 108 | |
| 109 | #define SHA3_STATESZ (sizeof(sha3_ctx)) |
| 110 | #define SHA3_224_STATESZ SHA3_STATESZ |
| 111 | #define SHA3_256_STATESZ SHA3_STATESZ |
| 112 | #define SHA3_384_STATESZ SHA3_STATESZ |
| 113 | #define SHA3_512_STATESZ SHA3_STATESZ |
| 114 | |
| 115 | /* --- @sha3_{224,256,384,512}_init@ --- * |
| 116 | * |
| 117 | * Arguments: @sha3_ctx *ctx@ = pointer to context block to initialize |
| 118 | * |
| 119 | * Returns: --- |
| 120 | * |
| 121 | * Use: Initializes a SHA3 hashing context for use. |
| 122 | */ |
| 123 | |
| 124 | extern void sha3_224_init(sha3_ctx */*ctx*/); |
| 125 | extern void sha3_256_init(sha3_ctx */*ctx*/); |
| 126 | extern void sha3_384_init(sha3_ctx */*ctx*/); |
| 127 | extern void sha3_512_init(sha3_ctx */*ctx*/); |
| 128 | |
| 129 | /* --- @sha3_hash@ --- * |
| 130 | * |
| 131 | * Arguments: @sha3_ctx *ctx@ = pointer to context bock |
| 132 | * @const void *p@ = pointer to data to hash |
| 133 | * @size_t sz@ = size of buffer to hash |
| 134 | * |
| 135 | * Returns: --- |
| 136 | * |
| 137 | * Use: Hashes a buffer of data. The buffer may be of any size and |
| 138 | * alignment. |
| 139 | */ |
| 140 | |
| 141 | #define sha3_224_hash sha3_hash |
| 142 | #define sha3_256_hash sha3_hash |
| 143 | #define sha3_384_hash sha3_hash |
| 144 | #define sha3_512_hash sha3_hash |
| 145 | |
| 146 | extern void sha3_hash(sha3_ctx */*ctx*/, const void */*p*/, size_t /*sz*/); |
| 147 | |
| 148 | /* --- @sha3_done@ --- * |
| 149 | * |
| 150 | * Arguments: @sha3_ctx *ctx@ = pointer to context block |
| 151 | * @void *hash@ = pointer to output buffer |
| 152 | * |
| 153 | * Returns: --- |
| 154 | * |
| 155 | * Use: Returns the hash of the data read so far. |
| 156 | */ |
| 157 | |
| 158 | #define sha3_224_done sha3_done |
| 159 | #define sha3_256_done sha3_done |
| 160 | #define sha3_384_done sha3_done |
| 161 | #define sha3_512_done sha3_done |
| 162 | |
| 163 | extern void sha3_done(sha3_ctx */*ctx*/, void */*hash*/); |
| 164 | |
| 165 | /*----- The cSHAKE XOF algorithm ------------------------------------------*/ |
| 166 | |
| 167 | typedef struct shake_ctx { |
| 168 | sha3_ctx h; |
| 169 | unsigned st, op; |
| 170 | } shake_ctx; |
| 171 | #define shake128_ctx shake_ctx |
| 172 | #define shake256_ctx shake_ctx |
| 173 | |
| 174 | #define SHAKE128_KEYSZ 16 |
| 175 | #define SHAKE256_KEYSZ 32 |
| 176 | |
| 177 | #define SHAKE128_HASHSZ 32 /* Somewhat arbitrary... */ |
| 178 | #define SHAKE256_HASHSZ 64 |
| 179 | |
| 180 | /* --- @cshake{128,256}_init@ --- * |
| 181 | * |
| 182 | * Arguments: @shake_ctx *ctx@ = pointer to context to initialize |
| 183 | * @const void *func@ = NIST-allocated function name |
| 184 | * @size_t fsz@ = length of function name |
| 185 | * @const void *perso@ = user personalization string |
| 186 | * @size_t psz@ = length of personalization string |
| 187 | * |
| 188 | * Returns: --- |
| 189 | * |
| 190 | * Use: Initializes a cSHAKE context. The context is initially in |
| 191 | * the `absorbing' state: feed it data with @shake_hash@. |
| 192 | */ |
| 193 | |
| 194 | extern void cshake128_init(shake_ctx */*ctx*/, |
| 195 | const void */*func*/, size_t /*fsz*/, |
| 196 | const void */*perso*/, size_t /*psz*/); |
| 197 | |
| 198 | extern void cshake256_init(shake_ctx */*ctx*/, |
| 199 | const void */*func*/, size_t /*fsz*/, |
| 200 | const void */*perso*/, size_t /*psz*/); |
| 201 | |
| 202 | /* --- @shake{128,256}_init@ --- * |
| 203 | * |
| 204 | * Arguments: @sha3_ctx *ctx@ = pointer to context to initialize |
| 205 | * |
| 206 | * Returns: --- |
| 207 | * |
| 208 | * Use: Initializes a SHAKE context. The context is initially in |
| 209 | * the `absorbing' state: feed it data with @shake_hash@. |
| 210 | */ |
| 211 | |
| 212 | extern void shake128_init(shake_ctx */*ctx*/); |
| 213 | extern void shake256_init(shake_ctx */*ctx*/); |
| 214 | |
| 215 | /* --- @shake_hash@ --- * |
| 216 | * |
| 217 | * Arguments: @shake_ctx *ctx@ = context to update |
| 218 | * @const void *p@ = input buffer |
| 219 | * @size_t sz@ = size of input |
| 220 | * |
| 221 | * Returns: --- |
| 222 | * |
| 223 | * Use: Feeds input data into a SHAKE context. The context must be |
| 224 | * in `absorbing' state. |
| 225 | */ |
| 226 | |
| 227 | extern void shake_hash(shake_ctx */*ctx*/, const void */*p*/, size_t /*sz*/); |
| 228 | |
| 229 | /* --- @shake_xof@ --- * |
| 230 | * |
| 231 | * Arguments: @shake_ctx *ctx@ = context to update |
| 232 | * |
| 233 | * Returns: --- |
| 234 | * |
| 235 | * Use: Switches the context into `squeezing' state. Use @shake_get@ |
| 236 | * or @shake_mask@ to extract data. |
| 237 | */ |
| 238 | |
| 239 | extern void shake_xof(shake_ctx */*ctx*/); |
| 240 | |
| 241 | /* --- @shake_get@ --- * |
| 242 | * |
| 243 | * Arguments: @shake_ctx *ctx@ = context to update |
| 244 | * @void *p@ = output buffer |
| 245 | * @size_t sz@ = size of output |
| 246 | * |
| 247 | * Returns: --- |
| 248 | * |
| 249 | * Use: Extracts output from a SHAKE context. The context must be |
| 250 | * in `squeezing' state. |
| 251 | */ |
| 252 | |
| 253 | extern void shake_get(shake_ctx */*ctx*/, void */*p*/, size_t /*sz*/); |
| 254 | |
| 255 | /* --- @shake_done@ --- * |
| 256 | * |
| 257 | * Arguments: @shake_ctx *ctx@ = context to update |
| 258 | * @void *h@ = where to write the hash |
| 259 | * @size_t hsz@ = size of the hash to make |
| 260 | * |
| 261 | * Returns: --- |
| 262 | * |
| 263 | * Use: Switches the context into `squeezing' state. Use @shake_get@ |
| 264 | * or @shake_mask@ to extract data. |
| 265 | */ |
| 266 | |
| 267 | extern void shake_done(shake_ctx */*ctx*/, void */*h*/, size_t /*hsz*/); |
| 268 | |
| 269 | /*----- That's all, folks -------------------------------------------------*/ |
| 270 | |
| 271 | #ifdef __cplusplus |
| 272 | } |
| 273 | #endif |
| 274 | |
| 275 | #endif |