| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Definitions electronic code book mode |
| 4 | * |
| 5 | * (c) 1999 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_ECB_DEF_H |
| 29 | #define CATACOMB_ECB_DEF_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Header files ------------------------------------------------------*/ |
| 36 | |
| 37 | #include <assert.h> |
| 38 | #include <string.h> |
| 39 | |
| 40 | #include <mLib/bits.h> |
| 41 | #include <mLib/sub.h> |
| 42 | |
| 43 | #ifndef CATACOMB_ARENA_H |
| 44 | # include "arena.h" |
| 45 | #endif |
| 46 | |
| 47 | #ifndef CATACOMB_BLKC_H |
| 48 | # include "blkc.h" |
| 49 | #endif |
| 50 | |
| 51 | #ifndef CATACOMB_GCIPHER_H |
| 52 | # include "gcipher.h" |
| 53 | #endif |
| 54 | |
| 55 | #ifndef CATACOMB_PARANOIA_H |
| 56 | # include "paranoia.h" |
| 57 | #endif |
| 58 | |
| 59 | /*----- Macros ------------------------------------------------------------*/ |
| 60 | |
| 61 | /* --- @ECB_DEF@ --- * |
| 62 | * |
| 63 | * Arguments: @PRE@, @pre@ = prefixes for the underlying block cipher |
| 64 | * |
| 65 | * Use: Creates an implementation for ECB stealing mode. |
| 66 | */ |
| 67 | |
| 68 | #define ECB_DEF(PRE, pre) ECB_DEFX(PRE, pre, #pre, #pre) |
| 69 | |
| 70 | #define ECB_DEFX(PRE, pre, name, fname) \ |
| 71 | \ |
| 72 | /* --- @pre_ecbsetkey@ --- * \ |
| 73 | * \ |
| 74 | * Arguments: @pre_ecbctx *ctx@ = pointer to ECB context block \ |
| 75 | * @const pre_ctx *k@ = pointer to cipher context \ |
| 76 | * \ |
| 77 | * Returns: --- \ |
| 78 | * \ |
| 79 | * Use: Sets the ECB context to use a different cipher key. \ |
| 80 | */ \ |
| 81 | \ |
| 82 | void pre##_ecbsetkey(pre##_ecbctx *ctx, const pre##_ctx *k) \ |
| 83 | { ctx->ctx = *k; } \ |
| 84 | \ |
| 85 | /* --- @pre_ecbinit@ --- * \ |
| 86 | * \ |
| 87 | * Arguments: @pre_ecbctx *ctx@ = pointer to cipher context \ |
| 88 | * @const void *key@ = pointer to the key buffer \ |
| 89 | * @size_t sz@ = size of the key \ |
| 90 | * @const void *iv@ = pointer to initialization vector \ |
| 91 | * \ |
| 92 | * Returns: --- \ |
| 93 | * \ |
| 94 | * Use: Initializes an ECB context ready for use. This is \ |
| 95 | * equivalent to calls to @pre_init@ and @pre_setkey@. \ |
| 96 | */ \ |
| 97 | \ |
| 98 | void pre##_ecbinit(pre##_ecbctx *ctx, \ |
| 99 | const void *key, size_t sz, \ |
| 100 | const void *iv) \ |
| 101 | { pre##_init(&ctx->ctx, key, sz); } \ |
| 102 | \ |
| 103 | /* --- @pre_ecbencrypt@ --- * \ |
| 104 | * \ |
| 105 | * Arguments: @pre_ecbctx *ctx@ = pointer to ECB context block \ |
| 106 | * @const void *src@ = pointer to source data \ |
| 107 | * @void *dest@ = pointer to destination data \ |
| 108 | * @size_t sz@ = size of block to be encrypted \ |
| 109 | * \ |
| 110 | * Returns: --- \ |
| 111 | * \ |
| 112 | * Use: Encrypts a block with a block cipher in ECB mode, with \ |
| 113 | * ciphertext stealing and other clever tricks. \ |
| 114 | * Essentially, data can be encrypted in arbitrary sized \ |
| 115 | * chunks, although decryption must use the same chunks. \ |
| 116 | */ \ |
| 117 | \ |
| 118 | void pre##_ecbencrypt(pre##_ecbctx *ctx, \ |
| 119 | const void *src, void *dest, \ |
| 120 | size_t sz) \ |
| 121 | { \ |
| 122 | const octet *s = src; \ |
| 123 | octet *d = dest; \ |
| 124 | uint32 t[PRE##_BLKSZ/4]; \ |
| 125 | octet b[PRE##_BLKSZ]; \ |
| 126 | octet y; \ |
| 127 | unsigned i; \ |
| 128 | \ |
| 129 | /* --- Empty blocks are trivial, and ECB is stateless --- */ \ |
| 130 | \ |
| 131 | if (!sz || !d) return; \ |
| 132 | \ |
| 133 | /* --- Short blocks aren't allowed in ECB --- * \ |
| 134 | * \ |
| 135 | * There's absolutely nothing secure I can do with them. \ |
| 136 | */ \ |
| 137 | \ |
| 138 | assert(((void)"ECB must have at least one whole block to work with", \ |
| 139 | sz >= PRE##_BLKSZ)); \ |
| 140 | \ |
| 141 | /* --- Do the main chunk of encryption --- * \ |
| 142 | * \ |
| 143 | * This will do the whole lot if it's a whole number of blocks. Just \ |
| 144 | * give each block to the cipher in turn. This is trivial. \ |
| 145 | * Hopefully... \ |
| 146 | */ \ |
| 147 | \ |
| 148 | while (sz >= 2*PRE##_BLKSZ || sz == PRE##_BLKSZ) { \ |
| 149 | if (!s) BLKC_ZERO(PRE, t); \ |
| 150 | else { BLKC_LOAD(PRE, t, s); s += PRE##_BLKSZ; } \ |
| 151 | pre##_eblk(&ctx->ctx, t, t); \ |
| 152 | BLKC_STORE(PRE, d, t); d += PRE##_BLKSZ; \ |
| 153 | sz -= PRE##_BLKSZ; \ |
| 154 | } \ |
| 155 | \ |
| 156 | /* --- Do the tail-end block and bit-left-over --- * \ |
| 157 | * \ |
| 158 | * This isn't very efficient. That shouldn't matter much. \ |
| 159 | */ \ |
| 160 | \ |
| 161 | if (sz) { \ |
| 162 | \ |
| 163 | /* --- Let @sz@ be the size of the partial block --- */ \ |
| 164 | \ |
| 165 | sz -= PRE##_BLKSZ; \ |
| 166 | \ |
| 167 | /* --- First stage --- * \ |
| 168 | * \ |
| 169 | * Read in the current block, and encrypt it. The first part of \ |
| 170 | * the result is the partial ciphertext block. Don't write that \ |
| 171 | * out yet, because I've not read the partial plaintext block. \ |
| 172 | */ \ |
| 173 | \ |
| 174 | if (!s) BLKC_ZERO(PRE, t); \ |
| 175 | else { BLKC_LOAD(PRE, t, s); s += PRE##_BLKSZ; } \ |
| 176 | pre##_eblk(&ctx->ctx, t, t); \ |
| 177 | BLKC_STORE(PRE, b, t); \ |
| 178 | \ |
| 179 | /* --- Second stage --- * \ |
| 180 | * \ |
| 181 | * Now move in the partial plaintext block, writing out the \ |
| 182 | * ciphertext as I go. Then encrypt, and write the complete \ |
| 183 | * ciphertext block. \ |
| 184 | */ \ |
| 185 | \ |
| 186 | d += PRE##_BLKSZ; \ |
| 187 | for (i = 0; i < sz; i++) { y = b[i]; b[i] = s[i]; d[i] = y; } \ |
| 188 | BLKC_LOAD(PRE, t, b); \ |
| 189 | pre##_eblk(&ctx->ctx, t, t); \ |
| 190 | BLKC_STORE(PRE, d - PRE##_BLKSZ, t); \ |
| 191 | } \ |
| 192 | \ |
| 193 | /* --- Done --- */ \ |
| 194 | \ |
| 195 | return; \ |
| 196 | } \ |
| 197 | \ |
| 198 | /* --- @pre_ecbdecrypt@ --- * \ |
| 199 | * \ |
| 200 | * Arguments: @pre_ecbctx *ctx@ = pointer to ECB context block \ |
| 201 | * @const void *src@ = pointer to source data \ |
| 202 | * @void *dest@ = pointer to destination data \ |
| 203 | * @size_t sz@ = size of block to be encrypted \ |
| 204 | * \ |
| 205 | * Returns: --- \ |
| 206 | * \ |
| 207 | * Use: Decrypts a block with a block cipher in ECB mode, with \ |
| 208 | * ciphertext stealing and other clever tricks. \ |
| 209 | * Essentially, data can be encrypted in arbitrary sized \ |
| 210 | * chunks, although decryption must use the same chunks. \ |
| 211 | */ \ |
| 212 | \ |
| 213 | void pre##_ecbdecrypt(pre##_ecbctx *ctx, \ |
| 214 | const void *src, void *dest, \ |
| 215 | size_t sz) \ |
| 216 | { \ |
| 217 | const octet *s = src; \ |
| 218 | octet *d = dest; \ |
| 219 | uint32 t[PRE##_BLKSZ/4]; \ |
| 220 | octet b[PRE##_BLKSZ]; \ |
| 221 | octet y; \ |
| 222 | unsigned i; \ |
| 223 | \ |
| 224 | /* --- Empty blocks are trivial --- */ \ |
| 225 | \ |
| 226 | if (!sz) return; \ |
| 227 | \ |
| 228 | /* --- Short blocks aren't allowed in ECB --- * \ |
| 229 | * \ |
| 230 | * There's absolutely nothing secure I can do with them. \ |
| 231 | */ \ |
| 232 | \ |
| 233 | assert(((void)"ECB must have at least one whole block to work with", \ |
| 234 | sz >= PRE##_BLKSZ)); \ |
| 235 | \ |
| 236 | /* --- Do the main chunk of decryption --- * \ |
| 237 | * \ |
| 238 | * This will do the whole lot if it's a whole number of blocks. \ |
| 239 | * Each block is just handed to the block cipher in turn. \ |
| 240 | */ \ |
| 241 | \ |
| 242 | while (sz >= 2*PRE##_BLKSZ || sz == PRE##_BLKSZ) { \ |
| 243 | BLKC_LOAD(PRE, t, s); s += PRE##_BLKSZ; \ |
| 244 | pre##_dblk(&ctx->ctx, t, t); \ |
| 245 | BLKC_STORE(PRE, d, t); d += PRE##_BLKSZ; \ |
| 246 | sz -= PRE##_BLKSZ; \ |
| 247 | } \ |
| 248 | \ |
| 249 | /* --- Do the tail-end block and bit-left-over --- * \ |
| 250 | * \ |
| 251 | * This isn't very efficient. That shouldn't matter much. \ |
| 252 | */ \ |
| 253 | \ |
| 254 | if (sz) { \ |
| 255 | \ |
| 256 | /* --- Let @sz@ be the size of the partial block --- */ \ |
| 257 | \ |
| 258 | sz -= PRE##_BLKSZ; \ |
| 259 | \ |
| 260 | /* --- First stage --- * \ |
| 261 | * \ |
| 262 | * Take the complete ciphertext block, and decrypt it. This block \ |
| 263 | * is carried over for the next encryption operation. \ |
| 264 | */ \ |
| 265 | \ |
| 266 | BLKC_LOAD(PRE, t, s); \ |
| 267 | pre##_dblk(&ctx->ctx, t, t); \ |
| 268 | BLKC_STORE(PRE, b, t); \ |
| 269 | \ |
| 270 | /* --- Second stage --- * \ |
| 271 | * \ |
| 272 | * The first few bytes are the partial plaintext block. Write that \ |
| 273 | * and replace with the partial ciphertext block. Then decrypt \ |
| 274 | * what's left as the complete plaintext. \ |
| 275 | */ \ |
| 276 | \ |
| 277 | s += PRE##_BLKSZ; \ |
| 278 | d += PRE##_BLKSZ; \ |
| 279 | for (i = 0; i < sz; i++) { y = s[i]; d[i] = b[i]; b[i] = y; } \ |
| 280 | BLKC_LOAD(PRE, t, b); \ |
| 281 | pre##_dblk(&ctx->ctx, t, t); \ |
| 282 | BLKC_STORE(PRE, d - PRE##_BLKSZ, t); \ |
| 283 | } \ |
| 284 | \ |
| 285 | /* --- Done --- */ \ |
| 286 | \ |
| 287 | return; \ |
| 288 | } \ |
| 289 | \ |
| 290 | /* --- Generic cipher interface --- */ \ |
| 291 | \ |
| 292 | static const gcipher_ops gops; \ |
| 293 | \ |
| 294 | typedef struct gctx { \ |
| 295 | gcipher c; \ |
| 296 | pre##_ecbctx k; \ |
| 297 | } gctx; \ |
| 298 | \ |
| 299 | static gcipher *ginit(const void *k, size_t sz) \ |
| 300 | { \ |
| 301 | gctx *g = S_CREATE(gctx); \ |
| 302 | g->c.ops = &gops; \ |
| 303 | pre##_ecbinit(&g->k, k, sz, 0); \ |
| 304 | return (&g->c); \ |
| 305 | } \ |
| 306 | \ |
| 307 | static void gencrypt(gcipher *c, const void *s, void *t, size_t sz) \ |
| 308 | { gctx *g = (gctx *)c; pre##_ecbencrypt(&g->k, s, t, sz); } \ |
| 309 | \ |
| 310 | static void gdecrypt(gcipher *c, const void *s, void *t, size_t sz) \ |
| 311 | { gctx *g = (gctx *)c; pre##_ecbdecrypt(&g->k, s, t, sz); } \ |
| 312 | \ |
| 313 | static void gdestroy(gcipher *c) \ |
| 314 | { gctx *g = (gctx *)c; BURN(*g); S_DESTROY(g); } \ |
| 315 | \ |
| 316 | static const gcipher_ops gops = { \ |
| 317 | &pre##_ecb, \ |
| 318 | gencrypt, gdecrypt, gdestroy, 0, 0 \ |
| 319 | }; \ |
| 320 | \ |
| 321 | const gccipher pre##_ecb = { \ |
| 322 | name "-ecb", pre##_keysz, PRE##_BLKSZ, \ |
| 323 | ginit \ |
| 324 | }; \ |
| 325 | \ |
| 326 | ECB_TESTX(PRE, pre, name, fname) |
| 327 | |
| 328 | /*----- Test rig ----------------------------------------------------------*/ |
| 329 | |
| 330 | #define ECB_TEST(PRE, pre) ECB_TESTX(PRE, pre, #pre, #pre) |
| 331 | |
| 332 | #ifdef TEST_RIG |
| 333 | |
| 334 | #include "modes-test.h" |
| 335 | |
| 336 | /* --- @ECB_TEST@ --- * |
| 337 | * |
| 338 | * Arguments: @PRE@, @pre@ = prefixes for block cipher definitions |
| 339 | * |
| 340 | * Use: Standard test rig for ECB functions. |
| 341 | */ |
| 342 | |
| 343 | #define ECB_TESTX(PRE, pre, name, fname) \ |
| 344 | \ |
| 345 | static pre##_ctx key; \ |
| 346 | static pre##_ecbctx ctx; \ |
| 347 | \ |
| 348 | static void pre##_ecb_test_setup(const octet *k, size_t ksz) \ |
| 349 | { pre##_init(&key, k, ksz); pre##_ecbsetkey(&ctx, &key); } \ |
| 350 | \ |
| 351 | static void pre##_ecb_test_reset(const octet *iv) \ |
| 352 | { ; } \ |
| 353 | \ |
| 354 | static void pre##_ecb_test_enc(const octet *s, octet *d, size_t sz) \ |
| 355 | { pre##_ecbencrypt(&ctx, s, d, sz); } \ |
| 356 | \ |
| 357 | static void pre##_ecb_test_dec(const octet *s, octet *d, size_t sz) \ |
| 358 | { pre##_ecbdecrypt(&ctx, s, d, sz); } \ |
| 359 | \ |
| 360 | int main(int argc, char *argv[]) \ |
| 361 | { \ |
| 362 | return test_encmode(fname "-ecb", PRE##_KEYSZ, PRE##_BLKSZ, \ |
| 363 | PRE##_BLKSZ, TEMF_REFALIGN, \ |
| 364 | pre##_ecb_test_setup, pre##_ecb_test_reset, \ |
| 365 | pre##_ecb_test_enc, pre##_ecb_test_dec, \ |
| 366 | argc, argv); \ |
| 367 | } |
| 368 | |
| 369 | #else |
| 370 | # define ECB_TESTX(PRE, pre, name, fname) |
| 371 | #endif |
| 372 | |
| 373 | /*----- That's all, folks -------------------------------------------------*/ |
| 374 | |
| 375 | #ifdef __cplusplus |
| 376 | } |
| 377 | #endif |
| 378 | |
| 379 | #endif |