| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Definitions for the MGF-1 mask generator |
| 4 | * |
| 5 | * (c) 2000 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Catacomb. |
| 11 | * |
| 12 | * Catacomb is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with Catacomb; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | #ifndef CATACOMB_MGF_DEF_H |
| 29 | #define CATACOMB_MGF_DEF_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Header files ------------------------------------------------------*/ |
| 36 | |
| 37 | #include <stdarg.h> |
| 38 | #include <stdlib.h> |
| 39 | #include <string.h> |
| 40 | |
| 41 | #include <mLib/bits.h> |
| 42 | #include <mLib/sub.h> |
| 43 | |
| 44 | #ifndef CATACOMB_ARENA_H |
| 45 | # include "arena.h" |
| 46 | #endif |
| 47 | |
| 48 | #ifndef CATACOMB_GCIPHER_H |
| 49 | # include "gcipher.h" |
| 50 | #endif |
| 51 | |
| 52 | #ifndef CATACOMB_GRAND_H |
| 53 | # include "grand.h" |
| 54 | #endif |
| 55 | |
| 56 | #ifndef CATACOMB_PARANOIA_H |
| 57 | # include "paranoia.h" |
| 58 | #endif |
| 59 | |
| 60 | /*----- Macros ------------------------------------------------------------*/ |
| 61 | |
| 62 | #define MGF_DEF(PRE, pre) MGF_DEFX(PRE, pre, #pre, #pre) |
| 63 | |
| 64 | #define MGF_DEFX(PRE, pre, name, fname) \ |
| 65 | \ |
| 66 | /* --- Useful constants --- */ \ |
| 67 | \ |
| 68 | const octet pre##_mgfkeysz[] = { KSZ_ANY, PRE##_HASHSZ }; \ |
| 69 | \ |
| 70 | /* --- @pre_mgfkeybegin@, @pre_mgfkeyadd@ --- * \ |
| 71 | * \ |
| 72 | * Arguments: @pre_mgfctx *k@ = pointer to context to initialize \ |
| 73 | * @const void *p@ = pointer to data to contribute \ |
| 74 | * \ |
| 75 | * Returns: --- \ |
| 76 | * \ |
| 77 | * Use: A multi-step keying procedure for initializing an MGF \ |
| 78 | * context. The data is contributed to a hashing context \ |
| 79 | * which is then used for mask generation. If you only \ |
| 80 | * have a fixed buffer, you can save a lot of effort by \ |
| 81 | * simply calling @pre_mgfinit@. \ |
| 82 | */ \ |
| 83 | \ |
| 84 | void pre##_mgfkeybegin(pre##_mgfctx *k) \ |
| 85 | { k->c = 0; k->off = 0; pre##_init(&k->k); } \ |
| 86 | \ |
| 87 | void pre##_mgfkeyadd(pre##_mgfctx *k, const void *p, size_t sz) \ |
| 88 | { pre##_hash(&k->k, p, sz); } \ |
| 89 | \ |
| 90 | /* ---- @pre_mgfinit@ --- * \ |
| 91 | * \ |
| 92 | * Arguments: @pre_mgfctx *k@ = pointer to context to initialize \ |
| 93 | * @const void *p@ = pointer to data to contribute \ |
| 94 | * @size_t sz@ = size of data to contribute \ |
| 95 | * \ |
| 96 | * Returns: --- \ |
| 97 | * \ |
| 98 | * Use: A simpler interface to initialization if all of your \ |
| 99 | * keying material is in one place. \ |
| 100 | */ \ |
| 101 | \ |
| 102 | void pre##_mgfinit(pre##_mgfctx *k, const void *p, size_t sz) \ |
| 103 | { k->c = 0; k->off = 0; pre##_init(&k->k); pre##_hash(&k->k, p, sz); } \ |
| 104 | \ |
| 105 | /* --- @pre_mgfencrypt@ --- * \ |
| 106 | * \ |
| 107 | * Arguments: @pre_mgfctx *k@ = pointer to masking context \ |
| 108 | * @const void *s@ = pointer to source buffer \ |
| 109 | * @void *d@ = pointer to destination buffer \ |
| 110 | * @size_t sz@ = size of buffers \ |
| 111 | * \ |
| 112 | * Returns: --- \ |
| 113 | * \ |
| 114 | * Use: Outputs pseudorandom data, or masks an input buffer. \ |
| 115 | * \ |
| 116 | * If @s@ is nonzero, the source material is exclusive- \ |
| 117 | * orred with the generated mask. If @d@ is zero, the \ |
| 118 | * generator is simply spun around for a while, which \ |
| 119 | * isn't very useful. \ |
| 120 | */ \ |
| 121 | \ |
| 122 | void pre##_mgfencrypt(pre##_mgfctx *k, const void *s, \ |
| 123 | void *d, size_t sz) \ |
| 124 | { \ |
| 125 | pre##_ctx h; \ |
| 126 | const octet *ss = s; \ |
| 127 | octet *dd = d; \ |
| 128 | const octet *p; \ |
| 129 | size_t off; \ |
| 130 | \ |
| 131 | /* --- Empty the buffer if there's anything there --- */ \ |
| 132 | \ |
| 133 | if (k->off) { \ |
| 134 | p = k->b + PRE##_HASHSZ - k->off; \ |
| 135 | off = sz > k->off ? k->off : sz; \ |
| 136 | sz -= off; k->off -= off; \ |
| 137 | if (!dd) /* do nothing */; \ |
| 138 | else if (!ss) { memcpy(dd, p, off); dd += off; } \ |
| 139 | else while (off--) *dd++ = *ss++ ^ *p++; \ |
| 140 | } \ |
| 141 | \ |
| 142 | /* --- While necessary, generate some more mask --- */ \ |
| 143 | \ |
| 144 | while (sz) { \ |
| 145 | STORE32(k->b, k->c); k->c++; \ |
| 146 | h = k->k; pre##_hash(&h, k->b, 4); pre##_done(&h, k->b); \ |
| 147 | off = sz > PRE##_HASHSZ ? PRE##_HASHSZ : sz; \ |
| 148 | k->off = PRE##_HASHSZ - off; \ |
| 149 | sz -= off; \ |
| 150 | p = k->b; \ |
| 151 | if (!dd) /* do nothing */; \ |
| 152 | else if (!ss) { memcpy(dd, p, off); dd += off; } \ |
| 153 | else while (off--) *dd++ = *ss++ ^ *p++; \ |
| 154 | } \ |
| 155 | } \ |
| 156 | \ |
| 157 | /* --- @pre_mgfsetindex@ --- * \ |
| 158 | * \ |
| 159 | * Arguments: @pre_mgfctx *k@ = pointer to masking context \ |
| 160 | * @uint32 *c@ = new index to set \ |
| 161 | * \ |
| 162 | * Returns: --- \ |
| 163 | * \ |
| 164 | * Use: Sets a new index. This may be used to step around the \ |
| 165 | * output stream in a rather crude way. \ |
| 166 | */ \ |
| 167 | \ |
| 168 | void pre##_mgfsetindex(pre##_mgfctx *k, uint32 c) \ |
| 169 | { k->c = c; k->off = 0; } \ |
| 170 | \ |
| 171 | /* --- Generic cipher interface --- */ \ |
| 172 | \ |
| 173 | static const gcipher_ops gops; \ |
| 174 | \ |
| 175 | typedef struct gctx { \ |
| 176 | gcipher c; \ |
| 177 | pre##_mgfctx k; \ |
| 178 | } gctx; \ |
| 179 | \ |
| 180 | static gcipher *ginit(const void *k, size_t sz) \ |
| 181 | { \ |
| 182 | gctx *g = S_CREATE(gctx); \ |
| 183 | g->c.ops = &gops; \ |
| 184 | pre##_mgfinit(&g->k, k, sz); \ |
| 185 | return (&g->c); \ |
| 186 | } \ |
| 187 | \ |
| 188 | static void gencrypt(gcipher *c, const void *s, void *t, size_t sz) \ |
| 189 | { gctx *g = (gctx *)c; pre##_mgfencrypt(&g->k, s, t, sz); } \ |
| 190 | \ |
| 191 | static void gdestroy(gcipher *c) \ |
| 192 | { gctx *g = (gctx *)c; BURN(*g); S_DESTROY(g); } \ |
| 193 | \ |
| 194 | static const gcipher_ops gops = { \ |
| 195 | &pre##_mgf, \ |
| 196 | gencrypt, gencrypt, gdestroy, 0, 0 \ |
| 197 | }; \ |
| 198 | \ |
| 199 | const gccipher pre##_mgf = { \ |
| 200 | name "-mgf", pre##_mgfkeysz, 0, \ |
| 201 | ginit \ |
| 202 | }; \ |
| 203 | \ |
| 204 | /* --- Generic random number generator interface --- */ \ |
| 205 | \ |
| 206 | typedef struct grctx { \ |
| 207 | grand r; \ |
| 208 | pre##_mgfctx k; \ |
| 209 | } grctx; \ |
| 210 | \ |
| 211 | static void grdestroy(grand *r) \ |
| 212 | { \ |
| 213 | grctx *g = (grctx *)r; \ |
| 214 | BURN(*g); \ |
| 215 | S_DESTROY(g); \ |
| 216 | } \ |
| 217 | \ |
| 218 | static int grmisc(grand *r, unsigned op, ...) \ |
| 219 | { \ |
| 220 | grctx *g = (grctx *)r; \ |
| 221 | va_list ap; \ |
| 222 | int rc = 0; \ |
| 223 | va_start(ap, op); \ |
| 224 | \ |
| 225 | switch (op) { \ |
| 226 | case GRAND_CHECK: \ |
| 227 | switch (va_arg(ap, unsigned)) { \ |
| 228 | case GRAND_CHECK: \ |
| 229 | case GRAND_SEEDINT: \ |
| 230 | case GRAND_SEEDUINT32: \ |
| 231 | case GRAND_SEEDBLOCK: \ |
| 232 | case GRAND_SEEDRAND: \ |
| 233 | rc = 1; \ |
| 234 | break; \ |
| 235 | default: \ |
| 236 | rc = 0; \ |
| 237 | break; \ |
| 238 | } \ |
| 239 | break; \ |
| 240 | case GRAND_SEEDINT: \ |
| 241 | pre##_mgfsetindex(&g->k, va_arg(ap, unsigned)); \ |
| 242 | break; \ |
| 243 | case GRAND_SEEDUINT32: \ |
| 244 | pre##_mgfsetindex(&g->k, va_arg(ap, uint32)); \ |
| 245 | break; \ |
| 246 | case GRAND_SEEDBLOCK: { \ |
| 247 | const void *p = va_arg(ap, const void *); \ |
| 248 | size_t sz = va_arg(ap, size_t); \ |
| 249 | pre##_hash(&g->k.k, p, sz); \ |
| 250 | } break; \ |
| 251 | case GRAND_SEEDRAND: { \ |
| 252 | octet buf[PRE##_BUFSZ]; \ |
| 253 | grand *rr = va_arg(ap, grand *); \ |
| 254 | rr->ops->fill(rr, buf, sizeof(buf)); \ |
| 255 | pre##_hash(&g->k.k, buf, sizeof(buf)); \ |
| 256 | } break; \ |
| 257 | default: \ |
| 258 | GRAND_BADOP; \ |
| 259 | break; \ |
| 260 | } \ |
| 261 | \ |
| 262 | va_end(ap); \ |
| 263 | return (rc); \ |
| 264 | } \ |
| 265 | \ |
| 266 | static octet grbyte(grand *r) \ |
| 267 | { \ |
| 268 | grctx *g = (grctx *)r; \ |
| 269 | octet o; \ |
| 270 | pre##_mgfencrypt(&g->k, 0, &o, 1); \ |
| 271 | return (o); \ |
| 272 | } \ |
| 273 | \ |
| 274 | static uint32 grword(grand *r) \ |
| 275 | { \ |
| 276 | grctx *g = (grctx *)r; \ |
| 277 | octet b[4]; \ |
| 278 | pre##_mgfencrypt(&g->k, 0, b, sizeof(b)); \ |
| 279 | return (LOAD32(b)); \ |
| 280 | } \ |
| 281 | \ |
| 282 | static void grfill(grand *r, void *p, size_t sz) \ |
| 283 | { grctx *g = (grctx *)r; pre##_mgfencrypt(&g->k, 0, p, sz); } \ |
| 284 | \ |
| 285 | static const grand_ops grops = { \ |
| 286 | name "-mgf", \ |
| 287 | GRAND_CRYPTO, 0, \ |
| 288 | grmisc, grdestroy, \ |
| 289 | grword, grbyte, grword, grand_defaultrange, grfill \ |
| 290 | }; \ |
| 291 | \ |
| 292 | /* --- @pre_mgfrand@ --- * \ |
| 293 | * \ |
| 294 | * Arguments: @const void *k@ = pointer to key material \ |
| 295 | * @size_t sz@ = size of key material \ |
| 296 | * \ |
| 297 | * Returns: Pointer to a generic random number generator instance. \ |
| 298 | * \ |
| 299 | * Use: Creates a random number interface wrapper around an \ |
| 300 | * MGF-1-mode hash function. \ |
| 301 | */ \ |
| 302 | \ |
| 303 | extern grand *pre##_mgfrand(const void *k, size_t sz) \ |
| 304 | { \ |
| 305 | grctx *g = S_CREATE(grctx); \ |
| 306 | g->r.ops = &grops; \ |
| 307 | pre##_mgfinit(&g->k, k, sz); \ |
| 308 | return (&g->r); \ |
| 309 | } \ |
| 310 | \ |
| 311 | MGF_TESTX(PRE, pre, name, fname) |
| 312 | |
| 313 | /*----- Test rig ----------------------------------------------------------*/ |
| 314 | |
| 315 | #define MGF_TEST(PRE, pre) MGF_TESTX(PRE, pre, #pre, #pre) |
| 316 | |
| 317 | #ifdef TEST_RIG |
| 318 | |
| 319 | #include "modes-test.h" |
| 320 | |
| 321 | /* --- @MGF_TEST@ --- * |
| 322 | * |
| 323 | * Arguments: @PRE@, @pre@ = prefixes for block cipher definitions |
| 324 | * |
| 325 | * Use: Standard test rig for MGF functions. |
| 326 | */ |
| 327 | |
| 328 | #define MGF_TESTX(PRE, pre, name, fname) \ |
| 329 | \ |
| 330 | static pre##_mgfctx ctx; \ |
| 331 | \ |
| 332 | static void pre##_mgf_test_setup(const octet *k, size_t ksz) \ |
| 333 | { pre##_mgfinit(&ctx, k, ksz); } \ |
| 334 | \ |
| 335 | static void pre##_mgf_test_reset(const octet *iv) \ |
| 336 | { pre##_mgfsetindex(&ctx, 0); } \ |
| 337 | \ |
| 338 | static void pre##_mgf_test_enc(const octet *s, octet *d, size_t sz) \ |
| 339 | { pre##_mgfencrypt(&ctx, s, d, sz); } \ |
| 340 | \ |
| 341 | int main(int argc, char *argv[]) \ |
| 342 | { \ |
| 343 | return test_encmode(fname "-mgf", 0, PRE##_HASHSZ, 1, 0, \ |
| 344 | pre##_mgf_test_setup, pre##_mgf_test_reset, \ |
| 345 | pre##_mgf_test_enc, pre##_mgf_test_enc, \ |
| 346 | argc, argv); \ |
| 347 | } |
| 348 | |
| 349 | #else |
| 350 | # define MGF_TESTX(PRE, pre, name, fname) |
| 351 | #endif |
| 352 | |
| 353 | /*----- That's all, folks -------------------------------------------------*/ |
| 354 | |
| 355 | #ifdef __cplusplus |
| 356 | } |
| 357 | #endif |
| 358 | |
| 359 | #endif |