| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * The GCM authenticated encryption mode |
| 4 | * |
| 5 | * (c) 2018 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 it |
| 13 | * under the terms of the GNU Library General Public License as published |
| 14 | * by the Free Software Foundation; either version 2 of the License, or |
| 15 | * (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, but |
| 18 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 20 | * 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 Software |
| 24 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
| 25 | * USA. |
| 26 | */ |
| 27 | |
| 28 | #ifndef CATACOMB_GCM_DEF_H |
| 29 | #define CATACOMB_GCM_DEF_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Header files ------------------------------------------------------*/ |
| 36 | |
| 37 | #include <string.h> |
| 38 | |
| 39 | #include <mLib/bits.h> |
| 40 | #include <mLib/sub.h> |
| 41 | |
| 42 | #ifndef CATACOMB_ARENA_H |
| 43 | # include "arena.h" |
| 44 | #endif |
| 45 | |
| 46 | #ifndef CATACOMB_BLKC_H |
| 47 | # include "blkc.h" |
| 48 | #endif |
| 49 | |
| 50 | #ifndef CATACOMB_CT_H |
| 51 | # include "ct.h" |
| 52 | #endif |
| 53 | |
| 54 | #ifndef CATACOMB_KEYSZ_H |
| 55 | # include "keysz.h" |
| 56 | #endif |
| 57 | |
| 58 | #ifndef CATACOMB_PARANOIA_H |
| 59 | # include "paranoia.h" |
| 60 | #endif |
| 61 | |
| 62 | #ifndef CATACOMB_RSVR_H |
| 63 | # include "rsvr.h" |
| 64 | #endif |
| 65 | |
| 66 | /*----- Type definitions --------------------------------------------------*/ |
| 67 | |
| 68 | typedef struct gcm_params { |
| 69 | unsigned f; /* flags */ |
| 70 | #define GCMF_SWAP 1u /* swap byte order? */ |
| 71 | unsigned n; /* number of words in block */ |
| 72 | uint32 poly; /* selected polynomial mask */ |
| 73 | } gcm_params; |
| 74 | |
| 75 | /*----- Utilities ---------------------------------------------------------*/ |
| 76 | |
| 77 | /* Supported block sizes. */ |
| 78 | #define GCM_WIDTHS(_) _(64) _(96) _(128) _(192) _(256) |
| 79 | #define GCM_NMAX 8 |
| 80 | |
| 81 | /* Polynomial tails for the supported block sizes. */ |
| 82 | #define GCM_POLY_64 0xd8000000 |
| 83 | #define GCM_POLY_96 0x82600000 |
| 84 | #define GCM_POLY_128 0xe1000000 |
| 85 | #define GCM_POLY_192 0xe1000000 |
| 86 | #define GCM_POLY_256 0xa4200000 |
| 87 | |
| 88 | /* Determine whether to set the @GCMF_SWAP@ flag. */ |
| 89 | #define GCM_SWAP_L GCMF_SWAP |
| 90 | #define GCM_SWAP_B 0 |
| 91 | |
| 92 | /* --- @gcm_mktable@ --- * |
| 93 | * |
| 94 | * Arguments: @const gcm_params *p@ = pointer to the parameters |
| 95 | * @uint32 *ktab@ = where to write the table; there must be |
| 96 | * space for %$32 n$% $%n$%-word entries, i.e., |
| 97 | * %$32 n^2$% 32-bit words in total, where %$n$% is |
| 98 | * @p->n@, the block size in words |
| 99 | * @const uint32 *k@ = input field element |
| 100 | * |
| 101 | * Returns: --- |
| 102 | * |
| 103 | * Use: Construct a table for use by @gcm_mulk_...@ below, to |
| 104 | * multiply (vaguely) efficiently by @k@. |
| 105 | */ |
| 106 | |
| 107 | extern void gcm_mktable(const gcm_params */*p*/, |
| 108 | uint32 */*ktab*/, const uint32 */*k*/); |
| 109 | |
| 110 | /* --- @gcm_mulk_N{b,l}@ --- * |
| 111 | * |
| 112 | * Arguments: @uint32 *a@ = accumulator to multiply |
| 113 | * @const uint32 *ktab@ = table constructed by @gcm_mktable@ |
| 114 | * |
| 115 | * Returns: --- |
| 116 | * |
| 117 | * Use: Multiply @a@ by @k@ (implicitly represented in @ktab@), |
| 118 | * updating @a@ in-place. There are separate functions for each |
| 119 | * supported block size and endianness because this is the |
| 120 | * function whose performance actually matters. |
| 121 | */ |
| 122 | |
| 123 | #define GCM_DECL_MULK(nbits) \ |
| 124 | extern void gcm_mulk_##nbits##b(uint32 */*a*/, const uint32 */*ktab*/); \ |
| 125 | extern void gcm_mulk_##nbits##l(uint32 */*a*/, const uint32 */*ktab*/); |
| 126 | GCM_WIDTHS(GCM_DECL_MULK) |
| 127 | #undef GCM_DECL_MULK |
| 128 | |
| 129 | /* Dispatch to the appropriate variant of @gcm_mulk@. */ |
| 130 | #define GCM_MULK(PRE, a, ktab) \ |
| 131 | BLKC_GLUE(GCM_MULK_, BLKC_ENDIAN(PRE))(BLKC_BITS(PRE), a, ktab) |
| 132 | #define GCM_MULK_B(nbits, a, ktab) \ |
| 133 | BLKC_GLUE(BLKC_GLUE(gcm_mulk_, nbits), b)(a, ktab) |
| 134 | #define GCM_MULK_L(nbits, a, ktab) \ |
| 135 | BLKC_GLUE(BLKC_GLUE(gcm_mulk_, nbits), l)(a, ktab) |
| 136 | |
| 137 | /* --- @gcm_ghashdone@ --- * |
| 138 | * |
| 139 | * Arguments: @const gcm_params *p@ = pointer to the parameters |
| 140 | * @uint32 *a@ = GHASH accumulator |
| 141 | * @const uint32 *ktab@ = multiplication table, built by |
| 142 | * @gcm_mktable@ |
| 143 | * @unsigned long xblocks, yblocks@ = number of whole blocks in |
| 144 | * the two inputs |
| 145 | * @unsigned xbytes, ybytes@ = number of trailing bytes in the |
| 146 | * two inputs |
| 147 | * |
| 148 | * Returns: --- |
| 149 | * |
| 150 | * Use: Finishes a GHASH operation by appending the appropriately |
| 151 | * encoded lengths of the two constituent messages. |
| 152 | */ |
| 153 | |
| 154 | extern void gcm_ghashdone(const gcm_params */*p*/, |
| 155 | uint32 */*a*/, const uint32 */*ktab*/, |
| 156 | unsigned long /*xblocks*/, unsigned /*xbytes*/, |
| 157 | unsigned long /*yblocks*/, unsigned /*ybytes*/); |
| 158 | |
| 159 | /* --- @gcm_concat@ --- * |
| 160 | * |
| 161 | * Arguments: @const gcm_params *p@ = pointer to the parameters |
| 162 | * @uint32 *z@ = GHASH accumulator for suffix, updated |
| 163 | * @const uint32 *x@ = GHASH accumulator for prefix |
| 164 | * @const uint32 *ktab@ = multiplication table, built by |
| 165 | * @gcm_mktable@ |
| 166 | * @unsigned long n@ = length of suffix in whole blocks |
| 167 | * |
| 168 | * Returns: --- |
| 169 | * |
| 170 | * Use: On entry, @x@ and @z@ are the results of hashing two strings |
| 171 | * %$a$% and %$b$%, each a whole number of blocks long; in |
| 172 | * particular, %$b$% is @n@ blocks long. On exit, @z@ is |
| 173 | * updated to be the hash of %$a \cat b$%. |
| 174 | */ |
| 175 | |
| 176 | extern void gcm_concat(const gcm_params */*p*/, |
| 177 | uint32 */*z*/, const uint32 */*x*/, |
| 178 | const uint32 */*ktab*/, unsigned long /*n*/); |
| 179 | |
| 180 | /* Step the counter using GCM's strange only-the-last-32-bits convention. */ |
| 181 | #define GCM_STEP(PRE, w) BLKC_GLUE(GCM_STEP_, BLKC_ENDIAN(PRE))(PRE, w) |
| 182 | #define GCM_STEP_B(PRE, w) GCM_STEP_X(PRE, BLKC_ID, w) |
| 183 | #define GCM_STEP_L(PRE, w) GCM_STEP_X(PRE, ENDSWAP32, w) |
| 184 | #define GCM_STEP_X(PRE, op, w) do { \ |
| 185 | BLKC_W(w); \ |
| 186 | _w[PRE##_BLKSZ/4 - 1] = op(op(_w[PRE##_BLKSZ/4 - 1]) + 1); \ |
| 187 | } while (0) |
| 188 | |
| 189 | /*----- Macros ------------------------------------------------------------*/ |
| 190 | |
| 191 | /* --- @GCM_DEF@ --- * |
| 192 | * |
| 193 | * Arguments: @PRE@, @pre@ = prefixes for the underlying block cipher |
| 194 | * |
| 195 | * Use: Creates an implementation for the GCM authenticated- |
| 196 | * encryption mode. |
| 197 | */ |
| 198 | |
| 199 | #define GCM_DEF(PRE, pre) GCM_DEFX(PRE, pre, #pre, #pre) |
| 200 | |
| 201 | #define GCM_DEFX(PRE, pre, name, fname) \ |
| 202 | \ |
| 203 | static const gcm_params pre##_gcmparams = { \ |
| 204 | BLKC_GLUE(GCM_SWAP_, BLKC_ENDIAN(PRE)), \ |
| 205 | PRE##_BLKSZ/4, \ |
| 206 | BLKC_GLUE(GCM_POLY_, BLKC_BITS(PRE)) \ |
| 207 | }; \ |
| 208 | \ |
| 209 | const octet \ |
| 210 | pre##_gcmnoncesz[] = { KSZ_ANY, PRE##_BLKSZ - 4 }, \ |
| 211 | pre##_gcmtagsz[] = { KSZ_RANGE, PRE##_BLKSZ, 0, PRE##_BLKSZ, 1 }; \ |
| 212 | \ |
| 213 | static const rsvr_policy pre##_gcmpolicy = { 0, PRE##_BLKSZ, PRE##_BLKSZ }; \ |
| 214 | \ |
| 215 | /* --- @pre_gcmsetkey@ --- * \ |
| 216 | * \ |
| 217 | * Arguments: @pre_gcmkey *key@ = pointer to key block to fill in \ |
| 218 | * @const void *k@ = pointer to key material \ |
| 219 | * @size_t ksz@ = size of key material \ |
| 220 | * \ |
| 221 | * Returns: --- \ |
| 222 | * \ |
| 223 | * Use: Initializes an GCM key block. \ |
| 224 | */ \ |
| 225 | \ |
| 226 | void pre##_gcmsetkey(pre##_gcmkey *key, const void *k, size_t ksz) \ |
| 227 | { \ |
| 228 | uint32 t[PRE##_BLKSZ/4]; \ |
| 229 | \ |
| 230 | /* Initialize the block cipher. */ \ |
| 231 | pre##_init(&key->ctx, k, ksz); \ |
| 232 | \ |
| 233 | /* Set up the GHASH multiplication table. */ \ |
| 234 | BLKC_ZERO(PRE, t); pre##_eblk(&key->ctx, t, t); \ |
| 235 | gcm_mktable(&pre##_gcmparams, key->ktab, t); \ |
| 236 | } \ |
| 237 | \ |
| 238 | /* --- @pre_gcmaadinit@ --- * \ |
| 239 | * \ |
| 240 | * Arguments: @pre_gcmaadctx *aad@ = pointer to AAD context \ |
| 241 | * @const pre_gcmkey *key@ = pointer to key block \ |
| 242 | * \ |
| 243 | * Returns: --- \ |
| 244 | * \ |
| 245 | * Use: Initializes an GCM AAD (`additional authenticated \ |
| 246 | * data') context associated with a given key. AAD \ |
| 247 | * contexts can be copied and/or reused, saving time if \ |
| 248 | * the AAD for a number of messages has a common prefix. \ |
| 249 | * \ |
| 250 | * The @key@ doesn't need to be kept around, though \ |
| 251 | * usually there'll at least be another copy in some GCM \ |
| 252 | * operation context because the AAD on its own isn't much \ |
| 253 | * good. \ |
| 254 | */ \ |
| 255 | \ |
| 256 | void pre##_gcmaadinit(pre##_gcmaadctx *aad, const pre##_gcmkey *key) \ |
| 257 | { aad->k = *key; aad->off = 0; aad->len = 0; BLKC_ZERO(PRE, aad->a); } \ |
| 258 | \ |
| 259 | /* --- @pre_gcmaadhash@ --- * \ |
| 260 | * \ |
| 261 | * Arguments: @pre_gcmaadctx *aad@ = pointer to AAD context \ |
| 262 | * @const void *p@ = pointer to AAD material \ |
| 263 | * @size_t sz@ = length of AAD material \ |
| 264 | * \ |
| 265 | * Returns: --- \ |
| 266 | * \ |
| 267 | * Use: Feeds AAD into the context. \ |
| 268 | */ \ |
| 269 | \ |
| 270 | void pre##_gcmaadhash(pre##_gcmaadctx *aad, const void *p, size_t sz) \ |
| 271 | { \ |
| 272 | rsvr_state st; \ |
| 273 | const octet *q; \ |
| 274 | \ |
| 275 | rsvr_setup(&st, &pre##_gcmpolicy, aad->b, &aad->off, p, sz); \ |
| 276 | RSVR_DO(&st) while ((q = RSVR_NEXT(&st, PRE##_BLKSZ)) != 0) { \ |
| 277 | BLKC_XLOAD(PRE, aad->a, q); GCM_MULK(PRE, aad->a, aad->k.ktab); \ |
| 278 | aad->len++; \ |
| 279 | } \ |
| 280 | } \ |
| 281 | \ |
| 282 | /* --- @pre_gcminit@ --- * \ |
| 283 | * \ |
| 284 | * Arguments: @pre_gcmctx *ctx@ = pointer to GCM context \ |
| 285 | * @const pre_gcmkey *key@ = pointer to key block \ |
| 286 | * @const void *n@ = pointer to nonce \ |
| 287 | * @size_t nsz@ = size of nonce \ |
| 288 | * \ |
| 289 | * Returns: --- \ |
| 290 | * \ |
| 291 | * Use: Initialize an GCM operation context with a given key. \ |
| 292 | * \ |
| 293 | * The original key needn't be kept around any more. \ |
| 294 | */ \ |
| 295 | \ |
| 296 | void pre##_gcminit(pre##_gcmctx *ctx, const pre##_gcmkey *k, \ |
| 297 | const void *n, size_t nsz) \ |
| 298 | { ctx->k = *k; pre##_gcmreinit(ctx, n, nsz); } \ |
| 299 | \ |
| 300 | /* --- @pre_gcmreinit@ --- * \ |
| 301 | * \ |
| 302 | * Arguments: @pre_gcmctx *ctx@ = pointer to GCM context \ |
| 303 | * @const void *n@ = pointer to nonce \ |
| 304 | * @size_t nsz@ = size of nonce \ |
| 305 | * \ |
| 306 | * Returns: --- \ |
| 307 | * \ |
| 308 | * Use: Reinitialize an GCM operation context, changing the \ |
| 309 | * nonce. \ |
| 310 | */ \ |
| 311 | \ |
| 312 | void pre##_gcmreinit(pre##_gcmctx *ctx, const void *n, size_t nsz) \ |
| 313 | { \ |
| 314 | octet b[PRE##_BLKSZ]; \ |
| 315 | const octet *q = n; \ |
| 316 | size_t nblocks; \ |
| 317 | unsigned i; \ |
| 318 | \ |
| 319 | /* Zero the counters. */ \ |
| 320 | ctx->off = 0; ctx->len = 0; \ |
| 321 | BLKC_ZERO(PRE, ctx->a); \ |
| 322 | \ |
| 323 | /* Calculate the initial counter from the nonce. */ \ |
| 324 | if (nsz == PRE##_BLKSZ - 4) { \ |
| 325 | /* Easy version: initialize the final word to 1 and copy the \ |
| 326 | * remaining words from the nonce. (The spec shows the nonce and \ |
| 327 | * counter the other way around for 64-bit block ciphers, but I'm \ |
| 328 | * sure this is just a mistake.) \ |
| 329 | */ \ |
| 330 | \ |
| 331 | for (i = 0; i < PRE##_BLKSZ/4 - 1; i++) \ |
| 332 | { ctx->c0[i] = BLKC_LOAD_E(PRE)(q); q += 4; } \ |
| 333 | ctx->c0[PRE##_BLKSZ/4 - 1] = BLKC_BWORD(PRE, 1); \ |
| 334 | } else { \ |
| 335 | /* Harder version: hash the nonce down with GHASH. */ \ |
| 336 | \ |
| 337 | BLKC_ZERO(PRE, ctx->c0); nblocks = 0; \ |
| 338 | while (nsz >= PRE##_BLKSZ) { \ |
| 339 | BLKC_XLOAD(PRE, ctx->c0, q); q += PRE##_BLKSZ; \ |
| 340 | GCM_MULK(PRE, ctx->c0, ctx->k.ktab); \ |
| 341 | nsz -= PRE##_BLKSZ; nblocks++; \ |
| 342 | } \ |
| 343 | if (nsz) { \ |
| 344 | memcpy(b, q, nsz); memset(b + nsz, 0, PRE##_BLKSZ - nsz); \ |
| 345 | BLKC_XLOAD(PRE, ctx->c0, b); \ |
| 346 | GCM_MULK(PRE, ctx->c0, ctx->k.ktab); \ |
| 347 | } \ |
| 348 | gcm_ghashdone(&pre##_gcmparams, ctx->c0, ctx->k.ktab, \ |
| 349 | 0, 0, nblocks, nsz); \ |
| 350 | } \ |
| 351 | \ |
| 352 | /* We must remember the initial counter for the final tag \ |
| 353 | * calculation. (I conjecture that storing the final counter instead \ |
| 354 | * would be just as secure, and require less state, but I've not \ |
| 355 | * proven this, and anyway it wouldn't interoperate.) Copy it to \ |
| 356 | * make the working counter. \ |
| 357 | */ \ |
| 358 | BLKC_MOVE(PRE, ctx->c, ctx->c0); \ |
| 359 | } \ |
| 360 | \ |
| 361 | /* --- @pre_gcmencrypt@ --- * \ |
| 362 | * \ |
| 363 | * Arguments: @pre_gcmctx *ctx@ = pointer to GCM operation context \ |
| 364 | * @const void *src@ = pointer to plaintext message chunk \ |
| 365 | * @size_t sz@ = size of the plaintext \ |
| 366 | * @buf *dst@ = a buffer to write the ciphertext to \ |
| 367 | * \ |
| 368 | * Returns: Zero on success; @-1@ on failure. \ |
| 369 | * \ |
| 370 | * Use: Encrypts a chunk of a plaintext message, writing a \ |
| 371 | * chunk of ciphertext to the output buffer and updating \ |
| 372 | * the operation state. \ |
| 373 | * \ |
| 374 | * For GCM, we always write a ciphertext chunk the same \ |
| 375 | * size as the plaintext. The messing about with @buf@ \ |
| 376 | * objects makes the interface consistent with other AEAD \ |
| 377 | * schemes which can't do this. \ |
| 378 | */ \ |
| 379 | \ |
| 380 | int pre##_gcmencrypt(pre##_gcmctx *ctx, \ |
| 381 | const void *src, size_t sz, buf *dst) \ |
| 382 | { \ |
| 383 | rsvr_plan plan; \ |
| 384 | uint32 t[PRE##_BLKSZ/4]; \ |
| 385 | const octet *p = src; \ |
| 386 | octet *q, *r, y; \ |
| 387 | \ |
| 388 | /* Allocate space for the ciphertext. */ \ |
| 389 | if (sz) { q = buf_get(dst, sz); if (!q) return (-1); } \ |
| 390 | else q = 0; \ |
| 391 | \ |
| 392 | /* Determine the buffering plan. Our buffer is going to do double- \ |
| 393 | * duty here. The end portion is going to contain mask from the \ |
| 394 | * encrypted counter which we mix into the plaintext to encrypt it; \ |
| 395 | * the start portion, which originally mask bytes we've already used, \ |
| 396 | * will hold the output ciphertext, which will eventually be \ |
| 397 | * collected into the GHASH state. \ |
| 398 | */ \ |
| 399 | rsvr_mkplan(&plan, &pre##_gcmpolicy, ctx->off, sz); \ |
| 400 | \ |
| 401 | /* Initial portion, fulfilled from the buffer. If the buffer is \ |
| 402 | * empty, then that means that we haven't yet encrypted the current \ |
| 403 | * counter, so we should do that and advance it. \ |
| 404 | */ \ |
| 405 | if (plan.head) { \ |
| 406 | if (!ctx->off) { \ |
| 407 | GCM_STEP(PRE, ctx->c); pre##_eblk(&ctx->k.ctx, ctx->c, t); \ |
| 408 | BLKC_STORE(PRE, ctx->b, t); \ |
| 409 | } \ |
| 410 | r = ctx->b + ctx->off; ctx->off += plan.head; \ |
| 411 | while (plan.head--) { y = *p++ ^ *r; *r++ = *q++ = y; } \ |
| 412 | } \ |
| 413 | \ |
| 414 | /* If we've filled up the buffer then we need to cycle the MAC and \ |
| 415 | * reset the offset. \ |
| 416 | */ \ |
| 417 | if (plan.from_rsvr) { \ |
| 418 | BLKC_XLOAD(PRE, ctx->a, ctx->b); GCM_MULK(PRE, ctx->a, ctx->k.ktab); \ |
| 419 | ctx->len++; ctx->off = 0; \ |
| 420 | } \ |
| 421 | \ |
| 422 | /* Now to process the main body of the input. */ \ |
| 423 | while (plan.from_input) { \ |
| 424 | GCM_STEP(PRE, ctx->c); pre##_eblk(&ctx->k.ctx, ctx->c, t); \ |
| 425 | BLKC_XLOAD(PRE, t, p); p += PRE##_BLKSZ; \ |
| 426 | BLKC_STORE(PRE, q, t); q += PRE##_BLKSZ; \ |
| 427 | BLKC_XMOVE(PRE, ctx->a, t); GCM_MULK(PRE, ctx->a, ctx->k.ktab); \ |
| 428 | plan.from_input -= PRE##_BLKSZ; ctx->len++; \ |
| 429 | } \ |
| 430 | \ |
| 431 | /* Finally, deal with any final portion. If there is one, we know \ |
| 432 | * that the buffer is empty: we must have filled it above, or this \ |
| 433 | * would all count as `initial' data. \ |
| 434 | */ \ |
| 435 | if (plan.tail) { \ |
| 436 | GCM_STEP(PRE, ctx->c); pre##_eblk(&ctx->k.ctx, ctx->c, t); \ |
| 437 | BLKC_STORE(PRE, ctx->b, t); \ |
| 438 | r = ctx->b; ctx->off += plan.tail; \ |
| 439 | while (plan.tail--) { y = *p++ ^ *r; *r++ = *q++ = y; } \ |
| 440 | } \ |
| 441 | \ |
| 442 | /* And we're done. */ \ |
| 443 | return (0); \ |
| 444 | } \ |
| 445 | \ |
| 446 | /* --- @pre_gcmdecrypt@ --- * \ |
| 447 | * \ |
| 448 | * Arguments: @pre_gcmctx *ctx@ = pointer to GCM operation context \ |
| 449 | * @const void *src@ = pointer to ciphertext message chunk \ |
| 450 | * @size_t sz@ = size of the ciphertext \ |
| 451 | * @buf *dst@ = a buffer to write the plaintext to \ |
| 452 | * \ |
| 453 | * Returns: Zero on success; @-1@ on failure. \ |
| 454 | * \ |
| 455 | * Use: Decrypts a chunk of a ciphertext message, writing a \ |
| 456 | * chunk of plaintext to the output buffer and updating \ |
| 457 | * the operation state. \ |
| 458 | * \ |
| 459 | * For GCM, we always write a plaintext chunk the same \ |
| 460 | * size as the ciphertext. The messing about with @buf@ \ |
| 461 | * objects makes the interface consistent with other AEAD \ |
| 462 | * schemes which can't do this. \ |
| 463 | */ \ |
| 464 | \ |
| 465 | int pre##_gcmdecrypt(pre##_gcmctx *ctx, \ |
| 466 | const void *src, size_t sz, buf *dst) \ |
| 467 | { \ |
| 468 | rsvr_plan plan; \ |
| 469 | uint32 t[PRE##_BLKSZ/4], u[PRE##_BLKSZ]; \ |
| 470 | const octet *p = src; \ |
| 471 | octet *q, *r, y; \ |
| 472 | \ |
| 473 | /* Allocate space for the plaintext. */ \ |
| 474 | if (sz) { q = buf_get(dst, sz); if (!q) return (-1); } \ |
| 475 | else q = 0; \ |
| 476 | \ |
| 477 | /* Determine the buffering plan. Our buffer is going to do double- \ |
| 478 | * duty here. The end portion is going to contain mask from the \ |
| 479 | * encrypted counter which we mix into the plaintext to encrypt it; \ |
| 480 | * the start portion, which originally mask bytes we've already used, \ |
| 481 | * will hold the input ciphertext, which will eventually be \ |
| 482 | * collected into the GHASH state. \ |
| 483 | */ \ |
| 484 | rsvr_mkplan(&plan, &pre##_gcmpolicy, ctx->off, sz); \ |
| 485 | \ |
| 486 | /* Initial portion, fulfilled from the buffer. If the buffer is \ |
| 487 | * empty, then that means that we haven't yet encrypted the current \ |
| 488 | * counter, so we should do that and advance it. \ |
| 489 | */ \ |
| 490 | if (plan.head) { \ |
| 491 | if (!ctx->off) { \ |
| 492 | GCM_STEP(PRE, ctx->c); pre##_eblk(&ctx->k.ctx, ctx->c, t); \ |
| 493 | BLKC_STORE(PRE, ctx->b, t); \ |
| 494 | } \ |
| 495 | r = ctx->b + ctx->off; ctx->off += plan.head; \ |
| 496 | while (plan.head--) { y = *p++; *q++ = y ^ *r; *r++ = y; } \ |
| 497 | } \ |
| 498 | \ |
| 499 | /* If we've filled up the buffer then we need to cycle the MAC and \ |
| 500 | * reset the offset. \ |
| 501 | */ \ |
| 502 | if (plan.from_rsvr) { \ |
| 503 | BLKC_XLOAD(PRE, ctx->a, ctx->b); GCM_MULK(PRE, ctx->a, ctx->k.ktab); \ |
| 504 | ctx->len++; ctx->off = 0; \ |
| 505 | } \ |
| 506 | \ |
| 507 | /* Now to process the main body of the input. */ \ |
| 508 | while (plan.from_input) { \ |
| 509 | GCM_STEP(PRE, ctx->c); pre##_eblk(&ctx->k.ctx, ctx->c, t); \ |
| 510 | BLKC_LOAD(PRE, u, p); p += PRE##_BLKSZ; \ |
| 511 | BLKC_XSTORE(PRE, q, t, u); q += PRE##_BLKSZ; \ |
| 512 | BLKC_XMOVE(PRE, ctx->a, u); GCM_MULK(PRE, ctx->a, ctx->k.ktab); \ |
| 513 | plan.from_input -= PRE##_BLKSZ; ctx->len++; \ |
| 514 | } \ |
| 515 | \ |
| 516 | /* Finally, deal with any final portion. If there is one, we know \ |
| 517 | * that the buffer is empty: we must have filled it above, or this \ |
| 518 | * would all count as `initial' data. \ |
| 519 | */ \ |
| 520 | if (plan.tail) { \ |
| 521 | GCM_STEP(PRE, ctx->c); pre##_eblk(&ctx->k.ctx, ctx->c, t); \ |
| 522 | BLKC_STORE(PRE, ctx->b, t); \ |
| 523 | r = ctx->b; ctx->off += plan.tail; \ |
| 524 | while (plan.tail--) { y = *p++; *q++ = y ^ *r; *r++ = y; } \ |
| 525 | } \ |
| 526 | \ |
| 527 | /* And we're done. */ \ |
| 528 | return (0); \ |
| 529 | } \ |
| 530 | \ |
| 531 | /* --- @pre_gcmtag@ --- * \ |
| 532 | * \ |
| 533 | * Arguments: @pre_gcmctx *ctx@ = pointer to an GCM context \ |
| 534 | * @const pre_gcmaadctx *aad@ = pointer to AAD context, or \ |
| 535 | * null \ |
| 536 | * @octet *t@ = where to write a (full-length) tag \ |
| 537 | * \ |
| 538 | * Returns: --- \ |
| 539 | * \ |
| 540 | * Use: Finishes an GCM operation, by calculating the tag. \ |
| 541 | */ \ |
| 542 | \ |
| 543 | static void pre##_gcmtag(pre##_gcmctx *ctx, \ |
| 544 | const pre##_gcmaadctx *aad, octet *t) \ |
| 545 | { \ |
| 546 | octet b[PRE##_BLKSZ]; \ |
| 547 | uint32 u[PRE##_BLKSZ/4]; \ |
| 548 | unsigned long n; \ |
| 549 | \ |
| 550 | /* Finish tagging the ciphertext. */ \ |
| 551 | if (ctx->off) { \ |
| 552 | memcpy(b, ctx->b, ctx->off); \ |
| 553 | memset(b + ctx->off, 0, PRE##_BLKSZ - ctx->off); \ |
| 554 | BLKC_XLOAD(PRE, ctx->a, b); GCM_MULK(PRE, ctx->a, ctx->k.ktab); \ |
| 555 | } \ |
| 556 | \ |
| 557 | /* If there's no AAD, because the pointer is null or no data was \ |
| 558 | * supplied, then apply that to the GHASH state. (Otherwise there's \ |
| 559 | * nothing to do here.) \ |
| 560 | */ \ |
| 561 | if (aad && (aad->len || aad->off)) { \ |
| 562 | BLKC_MOVE(PRE, u, aad->a); \ |
| 563 | if (aad->off) { \ |
| 564 | memcpy(b, aad->b, aad->off); \ |
| 565 | memset(b + aad->off, 0, PRE##_BLKSZ - aad->off); \ |
| 566 | BLKC_XLOAD(PRE, u, b); GCM_MULK(PRE, u, ctx->k.ktab); \ |
| 567 | } \ |
| 568 | n = ctx->len; if (ctx->off) n++; \ |
| 569 | gcm_concat(&pre##_gcmparams, ctx->a, u, ctx->k.ktab, n); \ |
| 570 | } \ |
| 571 | \ |
| 572 | /* Finish off the hash by appending the length. */ \ |
| 573 | gcm_ghashdone(&pre##_gcmparams, ctx->a, ctx->k.ktab, \ |
| 574 | aad ? aad->len : 0, aad ? aad->off : 0, \ |
| 575 | ctx->len, ctx->off); \ |
| 576 | \ |
| 577 | /* Mask the hash and store. */ \ |
| 578 | pre##_eblk(&ctx->k.ctx, ctx->c0, u); \ |
| 579 | BLKC_XSTORE(PRE, t, ctx->a, u); \ |
| 580 | } \ |
| 581 | \ |
| 582 | /* --- @pre_gcmencryptdone@ --- * \ |
| 583 | * \ |
| 584 | * Arguments: @pre_gcmctx *ctx@ = pointer to an GCM context \ |
| 585 | * @const pre_gcmaadctx *aad@ = pointer to AAD context, or \ |
| 586 | * null \ |
| 587 | * @buf *dst@ = buffer for remaining ciphertext \ |
| 588 | * @void *tag@ = where to write the tag \ |
| 589 | * @size_t tsz@ = length of tag to store \ |
| 590 | * \ |
| 591 | * Returns: Zero on success; @-1@ on failure. \ |
| 592 | * \ |
| 593 | * Use: Completes an GCM encryption operation. The @aad@ \ |
| 594 | * pointer may be null if there is no additional \ |
| 595 | * authenticated data. GCM doesn't buffer ciphertext, but \ |
| 596 | * the output buffer is provided anyway for consistency \ |
| 597 | * with other AEAD schemes which don't have this property; \ |
| 598 | * the function will fail if the output buffer is broken. \ |
| 599 | */ \ |
| 600 | \ |
| 601 | int pre##_gcmencryptdone(pre##_gcmctx *ctx, \ |
| 602 | const pre##_gcmaadctx *aad, buf *dst, \ |
| 603 | void *tag, size_t tsz) \ |
| 604 | { \ |
| 605 | octet t[PRE##_BLKSZ]; \ |
| 606 | \ |
| 607 | if (tsz > PRE##_BLKSZ) return (-1); \ |
| 608 | if (!BOK(dst)) return (-1); \ |
| 609 | pre##_gcmtag(ctx, aad, t); memcpy(tag, t, tsz); \ |
| 610 | return (0); \ |
| 611 | } \ |
| 612 | \ |
| 613 | /* --- @pre_gcmdecryptdone@ --- * \ |
| 614 | * \ |
| 615 | * Arguments: @pre_gcmctx *ctx@ = pointer to an GCM context \ |
| 616 | * @const pre_gcmaadctx *aad@ = pointer to AAD context, or \ |
| 617 | * null \ |
| 618 | * @buf *dst@ = buffer for remaining plaintext \ |
| 619 | * @const void *tag@ = tag to verify \ |
| 620 | * @size_t tsz@ = length of tag \ |
| 621 | * \ |
| 622 | * Returns: @+1@ for complete success; @0@ if tag verification \ |
| 623 | * failed; @-1@ for other kinds of errors. \ |
| 624 | * \ |
| 625 | * Use: Completes an GCM decryption operation. The @aad@ \ |
| 626 | * pointer may be null if there is no additional \ |
| 627 | * authenticated data. GCM doesn't buffer plaintext, but \ |
| 628 | * the output buffer is provided anyway for consistency \ |
| 629 | * with other AEAD schemes which don't have this property; \ |
| 630 | * the function will fail if the output buffer is broken. \ |
| 631 | */ \ |
| 632 | \ |
| 633 | int pre##_gcmdecryptdone(pre##_gcmctx *ctx, \ |
| 634 | const pre##_gcmaadctx *aad, buf *dst, \ |
| 635 | const void *tag, size_t tsz) \ |
| 636 | { \ |
| 637 | octet t[PRE##_BLKSZ]; \ |
| 638 | \ |
| 639 | if (tsz > PRE##_BLKSZ) return (-1); \ |
| 640 | if (!BOK(dst)) return (-1); \ |
| 641 | pre##_gcmtag(ctx, aad, t); \ |
| 642 | if (!ct_memeq(tag, t, tsz)) return (0); \ |
| 643 | else return (+1); \ |
| 644 | } \ |
| 645 | \ |
| 646 | /* --- Generic AEAD interface --- */ \ |
| 647 | \ |
| 648 | typedef struct gactx { \ |
| 649 | gaead_aad a; \ |
| 650 | pre##_gcmaadctx aad; \ |
| 651 | } gactx; \ |
| 652 | \ |
| 653 | static gaead_aad *gadup(const gaead_aad *a) \ |
| 654 | { gactx *aad = S_CREATE(gactx); *aad = *(gactx *)a; return (&aad->a); } \ |
| 655 | \ |
| 656 | static void gahash(gaead_aad *a, const void *h, size_t hsz) \ |
| 657 | { gactx *aad = (gactx *)a; pre##_gcmaadhash(&aad->aad, h, hsz); } \ |
| 658 | \ |
| 659 | static void gadestroy(gaead_aad *a) \ |
| 660 | { gactx *aad = (gactx *)a; BURN(*aad); S_DESTROY(aad); } \ |
| 661 | \ |
| 662 | static const gaead_aadops gaops = \ |
| 663 | { &pre##_gcm, gadup, gahash, gadestroy }; \ |
| 664 | \ |
| 665 | static gaead_aad *gaad(const pre##_gcmkey *k) \ |
| 666 | { \ |
| 667 | gactx *aad = S_CREATE(gactx); \ |
| 668 | aad->a.ops = &gaops; \ |
| 669 | pre##_gcmaadinit(&aad->aad, k); \ |
| 670 | return (&aad->a); \ |
| 671 | } \ |
| 672 | \ |
| 673 | typedef struct gectx { \ |
| 674 | gaead_enc e; \ |
| 675 | pre##_gcmctx ctx; \ |
| 676 | } gectx; \ |
| 677 | \ |
| 678 | static gaead_aad *geaad(gaead_enc *e) \ |
| 679 | { gectx *enc = (gectx *)e; return (gaad(&enc->ctx.k)); } \ |
| 680 | \ |
| 681 | static int gereinit(gaead_enc *e, const void *n, size_t nsz, \ |
| 682 | size_t hsz, size_t msz, size_t tsz) \ |
| 683 | { \ |
| 684 | gectx *enc = (gectx *)e; \ |
| 685 | \ |
| 686 | if (tsz > PRE##_BLKSZ) return (-1); \ |
| 687 | pre##_gcmreinit(&enc->ctx, n, nsz); \ |
| 688 | return (0); \ |
| 689 | } \ |
| 690 | \ |
| 691 | static int geenc(gaead_enc *e, const void *m, size_t msz, buf *b) \ |
| 692 | { \ |
| 693 | gectx *enc = (gectx *)e; \ |
| 694 | return (pre##_gcmencrypt(&enc->ctx, m, msz, b)); \ |
| 695 | } \ |
| 696 | \ |
| 697 | static int gedone(gaead_enc *e, const gaead_aad *a, \ |
| 698 | buf *b, void *t, size_t tsz) \ |
| 699 | { \ |
| 700 | gectx *enc = (gectx *)e; gactx *aad = (gactx *)a; \ |
| 701 | assert(!a || a->ops == &gaops); \ |
| 702 | return (pre##_gcmencryptdone(&enc->ctx, a ? &aad->aad : 0, b, t, tsz)); \ |
| 703 | } \ |
| 704 | \ |
| 705 | static void gedestroy(gaead_enc *e) \ |
| 706 | { gectx *enc = (gectx *)e; BURN(*enc); S_DESTROY(enc); } \ |
| 707 | \ |
| 708 | static const gaead_encops geops = \ |
| 709 | { &pre##_gcm, geaad, gereinit, geenc, gedone, gedestroy }; \ |
| 710 | \ |
| 711 | typedef struct gdctx { \ |
| 712 | gaead_dec d; \ |
| 713 | pre##_gcmctx ctx; \ |
| 714 | } gdctx; \ |
| 715 | \ |
| 716 | static gaead_aad *gdaad(gaead_dec *d) \ |
| 717 | { gdctx *dec = (gdctx *)d; return (gaad(&dec->ctx.k)); } \ |
| 718 | \ |
| 719 | static int gdreinit(gaead_dec *d, const void *n, size_t nsz, \ |
| 720 | size_t hsz, size_t csz, size_t tsz) \ |
| 721 | { \ |
| 722 | gdctx *dec = (gdctx *)d; \ |
| 723 | \ |
| 724 | if (tsz > PRE##_BLKSZ) return (-1); \ |
| 725 | pre##_gcmreinit(&dec->ctx, n, nsz); \ |
| 726 | return (0); \ |
| 727 | } \ |
| 728 | \ |
| 729 | static int gddec(gaead_dec *d, const void *c, size_t csz, buf *b) \ |
| 730 | { \ |
| 731 | gdctx *dec = (gdctx *)d; \ |
| 732 | return (pre##_gcmdecrypt(&dec->ctx, c, csz, b)); \ |
| 733 | } \ |
| 734 | \ |
| 735 | static int gddone(gaead_dec *d, const gaead_aad *a, \ |
| 736 | buf *b, const void *t, size_t tsz) \ |
| 737 | { \ |
| 738 | gdctx *dec = (gdctx *)d; gactx *aad = (gactx *)a; \ |
| 739 | assert(!a || a->ops == &gaops); \ |
| 740 | return (pre##_gcmdecryptdone(&dec->ctx, a ? &aad->aad : 0, b, t, tsz)); \ |
| 741 | } \ |
| 742 | \ |
| 743 | static void gddestroy(gaead_dec *d) \ |
| 744 | { gdctx *dec = (gdctx *)d; BURN(*dec); S_DESTROY(dec); } \ |
| 745 | \ |
| 746 | static const gaead_decops gdops = \ |
| 747 | { &pre##_gcm, gdaad, gdreinit, gddec, gddone, gddestroy }; \ |
| 748 | \ |
| 749 | typedef struct gkctx { \ |
| 750 | gaead_key k; \ |
| 751 | pre##_gcmkey key; \ |
| 752 | } gkctx; \ |
| 753 | \ |
| 754 | static gaead_aad *gkaad(const gaead_key *k) \ |
| 755 | { gkctx *key = (gkctx *)k; return (gaad(&key->key)); } \ |
| 756 | \ |
| 757 | static gaead_enc *gkenc(const gaead_key *k, const void *n, size_t nsz, \ |
| 758 | size_t hsz, size_t msz, size_t tsz) \ |
| 759 | { \ |
| 760 | gkctx *key = (gkctx *)k; \ |
| 761 | gectx *enc = S_CREATE(gectx); \ |
| 762 | \ |
| 763 | enc->e.ops = &geops; \ |
| 764 | pre##_gcminit(&enc->ctx, &key->key, n, nsz); \ |
| 765 | return (&enc->e); \ |
| 766 | } \ |
| 767 | \ |
| 768 | static gaead_dec *gkdec(const gaead_key *k, const void *n, size_t nsz, \ |
| 769 | size_t hsz, size_t csz, size_t tsz) \ |
| 770 | { \ |
| 771 | gkctx *key = (gkctx *)k; \ |
| 772 | gdctx *dec = S_CREATE(gdctx); \ |
| 773 | \ |
| 774 | dec->d.ops = &gdops; \ |
| 775 | pre##_gcminit(&dec->ctx, &key->key, n, nsz); \ |
| 776 | return (&dec->d); \ |
| 777 | } \ |
| 778 | \ |
| 779 | static void gkdestroy(gaead_key *k) \ |
| 780 | { gkctx *key = (gkctx *)k; BURN(*key); S_DESTROY(key); } \ |
| 781 | \ |
| 782 | static const gaead_keyops gkops = \ |
| 783 | { &pre##_gcm, gkaad, gkenc, gkdec, gkdestroy }; \ |
| 784 | \ |
| 785 | static gaead_key *gckey(const void *k, size_t ksz) \ |
| 786 | { \ |
| 787 | gkctx *key = S_CREATE(gkctx); \ |
| 788 | key->k.ops = &gkops; \ |
| 789 | pre##_gcmsetkey(&key->key, k, ksz); \ |
| 790 | return (&key->k); \ |
| 791 | } \ |
| 792 | \ |
| 793 | const gcaead pre##_gcm = { \ |
| 794 | name "-gcm", \ |
| 795 | pre##_keysz, pre##_gcmnoncesz, pre##_gcmtagsz, \ |
| 796 | PRE##_BLKSZ, 0, 0, 0, \ |
| 797 | gckey \ |
| 798 | }; \ |
| 799 | \ |
| 800 | GCM_TESTX(PRE, pre, name, fname) |
| 801 | |
| 802 | /*----- Test rig ----------------------------------------------------------*/ |
| 803 | |
| 804 | #define GCM_TEST(PRE, pre) GCM_TESTX(PRE, pre, #pre, #pre) |
| 805 | |
| 806 | /* --- @GCM_TEST@ --- * |
| 807 | * |
| 808 | * Arguments: @PRE, pre@ = prefixes for the underlying block cipher |
| 809 | * |
| 810 | * Use: Standard test rig for GCM functions. |
| 811 | */ |
| 812 | |
| 813 | #ifdef TEST_RIG |
| 814 | |
| 815 | #include <stdio.h> |
| 816 | |
| 817 | #include <mLib/dstr.h> |
| 818 | #include <mLib/quis.h> |
| 819 | #include <mLib/testrig.h> |
| 820 | |
| 821 | #define GCM_TESTX(PRE, pre, name, fname) \ |
| 822 | \ |
| 823 | static int gcmverify(dstr *v) \ |
| 824 | { \ |
| 825 | pre##_gcmkey key; \ |
| 826 | pre##_gcmaadctx aad; \ |
| 827 | pre##_gcmctx ctx; \ |
| 828 | int ok = 1, win; \ |
| 829 | int i; \ |
| 830 | octet *p; \ |
| 831 | int szs[] = { 1, 7, 192, -1, 0 }, *ip; \ |
| 832 | size_t hsz, msz; \ |
| 833 | dstr d = DSTR_INIT, t = DSTR_INIT; \ |
| 834 | buf b; \ |
| 835 | \ |
| 836 | dstr_ensure(&d, v[4].len > v[3].len ? v[4].len : v[3].len); \ |
| 837 | dstr_ensure(&t, v[5].len); t.len = v[5].len; \ |
| 838 | \ |
| 839 | pre##_gcmsetkey(&key, v[0].buf, v[0].len); \ |
| 840 | \ |
| 841 | for (ip = szs; *ip; ip++) { \ |
| 842 | \ |
| 843 | pre##_gcminit(&ctx, &key, (octet *)v[1].buf, v[1].len); \ |
| 844 | \ |
| 845 | i = *ip; \ |
| 846 | hsz = v[2].len; \ |
| 847 | if (i == -1) i = hsz; \ |
| 848 | if (i > hsz) continue; \ |
| 849 | p = (octet *)v[2].buf; \ |
| 850 | pre##_gcmaadinit(&aad, &key); \ |
| 851 | while (hsz) { \ |
| 852 | if (i > hsz) i = hsz; \ |
| 853 | pre##_gcmaadhash(&aad, p, i); \ |
| 854 | p += i; hsz -= i; \ |
| 855 | } \ |
| 856 | \ |
| 857 | buf_init(&b, d.buf, d.sz); \ |
| 858 | i = *ip; \ |
| 859 | msz = v[3].len; \ |
| 860 | if (i == -1) i = msz; \ |
| 861 | if (i > msz) continue; \ |
| 862 | p = (octet *)v[3].buf; \ |
| 863 | while (msz) { \ |
| 864 | if (i > msz) i = msz; \ |
| 865 | if (pre##_gcmencrypt(&ctx, p, i, &b)) { \ |
| 866 | puts("!! gcmencrypt reports failure"); \ |
| 867 | goto fail_enc; \ |
| 868 | } \ |
| 869 | p += i; msz -= i; \ |
| 870 | } \ |
| 871 | \ |
| 872 | if (pre##_gcmencryptdone(&ctx, &aad, &b, (octet *)t.buf, t.len)) { \ |
| 873 | puts("!! gcmencryptdone reports failure"); \ |
| 874 | goto fail_enc; \ |
| 875 | } \ |
| 876 | d.len = BLEN(&b); \ |
| 877 | \ |
| 878 | if (d.len != v[4].len || \ |
| 879 | memcmp(d.buf, v[4].buf, v[4].len) != 0 || \ |
| 880 | memcmp(t.buf, v[5].buf, v[5].len) != 0) { \ |
| 881 | fail_enc: \ |
| 882 | printf("\nfail encrypt:\n\tstep = %i", *ip); \ |
| 883 | fputs("\n\tkey = ", stdout); type_hex.dump(&v[0], stdout); \ |
| 884 | fputs("\n\tnonce = ", stdout); type_hex.dump(&v[1], stdout); \ |
| 885 | fputs("\n\theader = ", stdout); type_hex.dump(&v[2], stdout); \ |
| 886 | fputs("\n\tmessage = ", stdout); type_hex.dump(&v[3], stdout); \ |
| 887 | fputs("\n\texp ct = ", stdout); type_hex.dump(&v[4], stdout); \ |
| 888 | fputs("\n\tcalc ct = ", stdout); type_hex.dump(&d, stdout); \ |
| 889 | fputs("\n\texp tag = ", stdout); type_hex.dump(&v[5], stdout); \ |
| 890 | fputs("\n\tcalc tag = ", stdout); type_hex.dump(&t, stdout); \ |
| 891 | putchar('\n'); \ |
| 892 | ok = 0; \ |
| 893 | } \ |
| 894 | \ |
| 895 | pre##_gcminit(&ctx, &key, (octet *)v[1].buf, v[1].len); \ |
| 896 | \ |
| 897 | buf_init(&b, d.buf, d.sz); \ |
| 898 | i = *ip; \ |
| 899 | msz = v[4].len; \ |
| 900 | if (i == -1) i = msz; \ |
| 901 | if (i > msz) continue; \ |
| 902 | p = (octet *)v[4].buf; \ |
| 903 | while (msz) { \ |
| 904 | if (i > msz) i = msz; \ |
| 905 | if (pre##_gcmdecrypt(&ctx, p, i, &b)) { \ |
| 906 | puts("!! gcmdecrypt reports failure"); \ |
| 907 | win = 0; goto fail_dec; \ |
| 908 | } \ |
| 909 | p += i; msz -= i; \ |
| 910 | } \ |
| 911 | \ |
| 912 | win = pre##_gcmdecryptdone(&ctx, &aad, &b, \ |
| 913 | (octet *)v[5].buf, v[5].len); \ |
| 914 | if (win < 0) { \ |
| 915 | puts("!! gcmdecryptdone reports failure"); \ |
| 916 | goto fail_dec; \ |
| 917 | } \ |
| 918 | d.len = BLEN(&b); \ |
| 919 | \ |
| 920 | if (d.len != v[3].len || !win || \ |
| 921 | memcmp(d.buf, v[3].buf, v[3].len) != 0) { \ |
| 922 | fail_dec: \ |
| 923 | printf("\nfail decrypt:\n\tstep = %i", *ip); \ |
| 924 | fputs("\n\tkey = ", stdout); type_hex.dump(&v[0], stdout); \ |
| 925 | fputs("\n\tnonce = ", stdout); type_hex.dump(&v[1], stdout); \ |
| 926 | fputs("\n\theader = ", stdout); type_hex.dump(&v[2], stdout); \ |
| 927 | fputs("\n\tciphertext = ", stdout); type_hex.dump(&v[4], stdout); \ |
| 928 | fputs("\n\texp pt = ", stdout); type_hex.dump(&v[3], stdout); \ |
| 929 | fputs("\n\tcalc pt = ", stdout); type_hex.dump(&d, stdout); \ |
| 930 | fputs("\n\ttag = ", stdout); type_hex.dump(&v[5], stdout); \ |
| 931 | printf("\n\tverify %s", win ? "ok" : "FAILED"); \ |
| 932 | putchar('\n'); \ |
| 933 | ok = 0; \ |
| 934 | } \ |
| 935 | } \ |
| 936 | \ |
| 937 | dstr_destroy(&d); dstr_destroy(&t); \ |
| 938 | return (ok); \ |
| 939 | } \ |
| 940 | \ |
| 941 | static test_chunk aeaddefs[] = { \ |
| 942 | { name "-gcm", gcmverify, \ |
| 943 | { &type_hex, &type_hex, &type_hex, &type_hex, \ |
| 944 | &type_hex, &type_hex, 0 } }, \ |
| 945 | { 0, 0, { 0 } } \ |
| 946 | }; \ |
| 947 | \ |
| 948 | int main(int argc, char *argv[]) \ |
| 949 | { \ |
| 950 | ego(argv[0]); \ |
| 951 | test_run(argc, argv, aeaddefs, SRCDIR"/t/" fname); \ |
| 952 | return (0); \ |
| 953 | } |
| 954 | |
| 955 | #else |
| 956 | # define GCM_TESTX(PRE, pre, name, fname) |
| 957 | #endif |
| 958 | |
| 959 | /*----- That's all, folks -------------------------------------------------*/ |
| 960 | |
| 961 | #ifdef __cplusplus |
| 962 | } |
| 963 | #endif |
| 964 | |
| 965 | #endif |