gcm.c 30 KB

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  1. /*
  2. * NIST SP800-38D compliant GCM implementation
  3. *
  4. * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
  5. * SPDX-License-Identifier: Apache-2.0
  6. *
  7. * Licensed under the Apache License, Version 2.0 (the "License"); you may
  8. * not use this file except in compliance with the License.
  9. * You may obtain a copy of the License at
  10. *
  11. * http://www.apache.org/licenses/LICENSE-2.0
  12. *
  13. * Unless required by applicable law or agreed to in writing, software
  14. * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  15. * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16. * See the License for the specific language governing permissions and
  17. * limitations under the License.
  18. *
  19. * This file is part of mbed TLS (https://tls.mbed.org)
  20. */
  21. /*
  22. * http://csrc.nist.gov/publications/nistpubs/800-38D/SP-800-38D.pdf
  23. *
  24. * See also:
  25. * [MGV] http://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-revised-spec.pdf
  26. *
  27. * We use the algorithm described as Shoup's method with 4-bit tables in
  28. * [MGV] 4.1, pp. 12-13, to enhance speed without using too much memory.
  29. */
  30. #if !defined(MBEDTLS_CONFIG_FILE)
  31. #include "mbedtls/config.h"
  32. #else
  33. #include MBEDTLS_CONFIG_FILE
  34. #endif
  35. #if defined(MBEDTLS_GCM_C)
  36. #include "mbedtls/gcm.h"
  37. #include <string.h>
  38. #if defined(MBEDTLS_AESNI_C)
  39. #include "mbedtls/aesni.h"
  40. #endif
  41. #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
  42. #include "mbedtls/aes.h"
  43. #if defined(MBEDTLS_PLATFORM_C)
  44. #include "mbedtls/platform.h"
  45. #else
  46. #include <stdio.h>
  47. #define mbedtls_printf printf
  48. #endif /* MBEDTLS_PLATFORM_C */
  49. #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
  50. #if !defined(MBEDTLS_GCM_ALT)
  51. /*
  52. * 32-bit integer manipulation macros (big endian)
  53. */
  54. #ifndef GET_UINT32_BE
  55. #define GET_UINT32_BE(n,b,i) \
  56. { \
  57. (n) = ( (uint32_t) (b)[(i) ] << 24 ) \
  58. | ( (uint32_t) (b)[(i) + 1] << 16 ) \
  59. | ( (uint32_t) (b)[(i) + 2] << 8 ) \
  60. | ( (uint32_t) (b)[(i) + 3] ); \
  61. }
  62. #endif
  63. #ifndef PUT_UINT32_BE
  64. #define PUT_UINT32_BE(n,b,i) \
  65. { \
  66. (b)[(i) ] = (unsigned char) ( (n) >> 24 ); \
  67. (b)[(i) + 1] = (unsigned char) ( (n) >> 16 ); \
  68. (b)[(i) + 2] = (unsigned char) ( (n) >> 8 ); \
  69. (b)[(i) + 3] = (unsigned char) ( (n) ); \
  70. }
  71. #endif
  72. /* Implementation that should never be optimized out by the compiler */
  73. static void mbedtls_zeroize( void *v, size_t n ) {
  74. volatile unsigned char *p = v; while( n-- ) *p++ = 0;
  75. }
  76. /*
  77. * Initialize a context
  78. */
  79. void mbedtls_gcm_init( mbedtls_gcm_context *ctx )
  80. {
  81. memset( ctx, 0, sizeof( mbedtls_gcm_context ) );
  82. }
  83. /*
  84. * Precompute small multiples of H, that is set
  85. * HH[i] || HL[i] = H times i,
  86. * where i is seen as a field element as in [MGV], ie high-order bits
  87. * correspond to low powers of P. The result is stored in the same way, that
  88. * is the high-order bit of HH corresponds to P^0 and the low-order bit of HL
  89. * corresponds to P^127.
  90. */
  91. static int gcm_gen_table( mbedtls_gcm_context *ctx )
  92. {
  93. int ret, i, j;
  94. uint64_t hi, lo;
  95. uint64_t vl, vh;
  96. unsigned char h[16];
  97. size_t olen = 0;
  98. memset( h, 0, 16 );
  99. if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, h, 16, h, &olen ) ) != 0 )
  100. return( ret );
  101. /* pack h as two 64-bits ints, big-endian */
  102. GET_UINT32_BE( hi, h, 0 );
  103. GET_UINT32_BE( lo, h, 4 );
  104. vh = (uint64_t) hi << 32 | lo;
  105. GET_UINT32_BE( hi, h, 8 );
  106. GET_UINT32_BE( lo, h, 12 );
  107. vl = (uint64_t) hi << 32 | lo;
  108. /* 8 = 1000 corresponds to 1 in GF(2^128) */
  109. ctx->HL[8] = vl;
  110. ctx->HH[8] = vh;
  111. #if defined(MBEDTLS_AESNI_C) && defined(MBEDTLS_HAVE_X86_64)
  112. /* With CLMUL support, we need only h, not the rest of the table */
  113. if( mbedtls_aesni_has_support( MBEDTLS_AESNI_CLMUL ) )
  114. return( 0 );
  115. #endif
  116. /* 0 corresponds to 0 in GF(2^128) */
  117. ctx->HH[0] = 0;
  118. ctx->HL[0] = 0;
  119. for( i = 4; i > 0; i >>= 1 )
  120. {
  121. uint32_t T = ( vl & 1 ) * 0xe1000000U;
  122. vl = ( vh << 63 ) | ( vl >> 1 );
  123. vh = ( vh >> 1 ) ^ ( (uint64_t) T << 32);
  124. ctx->HL[i] = vl;
  125. ctx->HH[i] = vh;
  126. }
  127. for( i = 2; i <= 8; i *= 2 )
  128. {
  129. uint64_t *HiL = ctx->HL + i, *HiH = ctx->HH + i;
  130. vh = *HiH;
  131. vl = *HiL;
  132. for( j = 1; j < i; j++ )
  133. {
  134. HiH[j] = vh ^ ctx->HH[j];
  135. HiL[j] = vl ^ ctx->HL[j];
  136. }
  137. }
  138. return( 0 );
  139. }
  140. int mbedtls_gcm_setkey( mbedtls_gcm_context *ctx,
  141. mbedtls_cipher_id_t cipher,
  142. const unsigned char *key,
  143. unsigned int keybits )
  144. {
  145. int ret;
  146. const mbedtls_cipher_info_t *cipher_info;
  147. cipher_info = mbedtls_cipher_info_from_values( cipher, keybits, MBEDTLS_MODE_ECB );
  148. if( cipher_info == NULL )
  149. return( MBEDTLS_ERR_GCM_BAD_INPUT );
  150. if( cipher_info->block_size != 16 )
  151. return( MBEDTLS_ERR_GCM_BAD_INPUT );
  152. mbedtls_cipher_free( &ctx->cipher_ctx );
  153. if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
  154. return( ret );
  155. if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
  156. MBEDTLS_ENCRYPT ) ) != 0 )
  157. {
  158. return( ret );
  159. }
  160. if( ( ret = gcm_gen_table( ctx ) ) != 0 )
  161. return( ret );
  162. return( 0 );
  163. }
  164. /*
  165. * Shoup's method for multiplication use this table with
  166. * last4[x] = x times P^128
  167. * where x and last4[x] are seen as elements of GF(2^128) as in [MGV]
  168. */
  169. static const uint64_t last4[16] =
  170. {
  171. 0x0000, 0x1c20, 0x3840, 0x2460,
  172. 0x7080, 0x6ca0, 0x48c0, 0x54e0,
  173. 0xe100, 0xfd20, 0xd940, 0xc560,
  174. 0x9180, 0x8da0, 0xa9c0, 0xb5e0
  175. };
  176. /*
  177. * Sets output to x times H using the precomputed tables.
  178. * x and output are seen as elements of GF(2^128) as in [MGV].
  179. */
  180. static void gcm_mult( mbedtls_gcm_context *ctx, const unsigned char x[16],
  181. unsigned char output[16] )
  182. {
  183. int i = 0;
  184. unsigned char lo, hi, rem;
  185. uint64_t zh, zl;
  186. #if defined(MBEDTLS_AESNI_C) && defined(MBEDTLS_HAVE_X86_64)
  187. if( mbedtls_aesni_has_support( MBEDTLS_AESNI_CLMUL ) ) {
  188. unsigned char h[16];
  189. PUT_UINT32_BE( ctx->HH[8] >> 32, h, 0 );
  190. PUT_UINT32_BE( ctx->HH[8], h, 4 );
  191. PUT_UINT32_BE( ctx->HL[8] >> 32, h, 8 );
  192. PUT_UINT32_BE( ctx->HL[8], h, 12 );
  193. mbedtls_aesni_gcm_mult( output, x, h );
  194. return;
  195. }
  196. #endif /* MBEDTLS_AESNI_C && MBEDTLS_HAVE_X86_64 */
  197. lo = x[15] & 0xf;
  198. zh = ctx->HH[lo];
  199. zl = ctx->HL[lo];
  200. for( i = 15; i >= 0; i-- )
  201. {
  202. lo = x[i] & 0xf;
  203. hi = x[i] >> 4;
  204. if( i != 15 )
  205. {
  206. rem = (unsigned char) zl & 0xf;
  207. zl = ( zh << 60 ) | ( zl >> 4 );
  208. zh = ( zh >> 4 );
  209. zh ^= (uint64_t) last4[rem] << 48;
  210. zh ^= ctx->HH[lo];
  211. zl ^= ctx->HL[lo];
  212. }
  213. rem = (unsigned char) zl & 0xf;
  214. zl = ( zh << 60 ) | ( zl >> 4 );
  215. zh = ( zh >> 4 );
  216. zh ^= (uint64_t) last4[rem] << 48;
  217. zh ^= ctx->HH[hi];
  218. zl ^= ctx->HL[hi];
  219. }
  220. PUT_UINT32_BE( zh >> 32, output, 0 );
  221. PUT_UINT32_BE( zh, output, 4 );
  222. PUT_UINT32_BE( zl >> 32, output, 8 );
  223. PUT_UINT32_BE( zl, output, 12 );
  224. }
  225. int mbedtls_gcm_starts( mbedtls_gcm_context *ctx,
  226. int mode,
  227. const unsigned char *iv,
  228. size_t iv_len,
  229. const unsigned char *add,
  230. size_t add_len )
  231. {
  232. int ret;
  233. unsigned char work_buf[16];
  234. size_t i;
  235. const unsigned char *p;
  236. size_t use_len, olen = 0;
  237. /* IV and AD are limited to 2^64 bits, so 2^61 bytes */
  238. /* IV is not allowed to be zero length */
  239. if( iv_len == 0 ||
  240. ( (uint64_t) iv_len ) >> 61 != 0 ||
  241. ( (uint64_t) add_len ) >> 61 != 0 )
  242. {
  243. return( MBEDTLS_ERR_GCM_BAD_INPUT );
  244. }
  245. memset( ctx->y, 0x00, sizeof(ctx->y) );
  246. memset( ctx->buf, 0x00, sizeof(ctx->buf) );
  247. ctx->mode = mode;
  248. ctx->len = 0;
  249. ctx->add_len = 0;
  250. if( iv_len == 12 )
  251. {
  252. memcpy( ctx->y, iv, iv_len );
  253. ctx->y[15] = 1;
  254. }
  255. else
  256. {
  257. memset( work_buf, 0x00, 16 );
  258. PUT_UINT32_BE( iv_len * 8, work_buf, 12 );
  259. p = iv;
  260. while( iv_len > 0 )
  261. {
  262. use_len = ( iv_len < 16 ) ? iv_len : 16;
  263. for( i = 0; i < use_len; i++ )
  264. ctx->y[i] ^= p[i];
  265. gcm_mult( ctx, ctx->y, ctx->y );
  266. iv_len -= use_len;
  267. p += use_len;
  268. }
  269. for( i = 0; i < 16; i++ )
  270. ctx->y[i] ^= work_buf[i];
  271. gcm_mult( ctx, ctx->y, ctx->y );
  272. }
  273. if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctx->y, 16, ctx->base_ectr,
  274. &olen ) ) != 0 )
  275. {
  276. return( ret );
  277. }
  278. ctx->add_len = add_len;
  279. p = add;
  280. while( add_len > 0 )
  281. {
  282. use_len = ( add_len < 16 ) ? add_len : 16;
  283. for( i = 0; i < use_len; i++ )
  284. ctx->buf[i] ^= p[i];
  285. gcm_mult( ctx, ctx->buf, ctx->buf );
  286. add_len -= use_len;
  287. p += use_len;
  288. }
  289. return( 0 );
  290. }
  291. int mbedtls_gcm_update( mbedtls_gcm_context *ctx,
  292. size_t length,
  293. const unsigned char *input,
  294. unsigned char *output )
  295. {
  296. int ret;
  297. unsigned char ectr[16];
  298. size_t i;
  299. const unsigned char *p;
  300. unsigned char *out_p = output;
  301. size_t use_len, olen = 0;
  302. if( output > input && (size_t) ( output - input ) < length )
  303. return( MBEDTLS_ERR_GCM_BAD_INPUT );
  304. /* Total length is restricted to 2^39 - 256 bits, ie 2^36 - 2^5 bytes
  305. * Also check for possible overflow */
  306. if( ctx->len + length < ctx->len ||
  307. (uint64_t) ctx->len + length > 0xFFFFFFFE0ull )
  308. {
  309. return( MBEDTLS_ERR_GCM_BAD_INPUT );
  310. }
  311. ctx->len += length;
  312. p = input;
  313. while( length > 0 )
  314. {
  315. use_len = ( length < 16 ) ? length : 16;
  316. for( i = 16; i > 12; i-- )
  317. if( ++ctx->y[i - 1] != 0 )
  318. break;
  319. if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctx->y, 16, ectr,
  320. &olen ) ) != 0 )
  321. {
  322. return( ret );
  323. }
  324. for( i = 0; i < use_len; i++ )
  325. {
  326. if( ctx->mode == MBEDTLS_GCM_DECRYPT )
  327. ctx->buf[i] ^= p[i];
  328. out_p[i] = ectr[i] ^ p[i];
  329. if( ctx->mode == MBEDTLS_GCM_ENCRYPT )
  330. ctx->buf[i] ^= out_p[i];
  331. }
  332. gcm_mult( ctx, ctx->buf, ctx->buf );
  333. length -= use_len;
  334. p += use_len;
  335. out_p += use_len;
  336. }
  337. return( 0 );
  338. }
  339. int mbedtls_gcm_finish( mbedtls_gcm_context *ctx,
  340. unsigned char *tag,
  341. size_t tag_len )
  342. {
  343. unsigned char work_buf[16];
  344. size_t i;
  345. uint64_t orig_len = ctx->len * 8;
  346. uint64_t orig_add_len = ctx->add_len * 8;
  347. if( tag_len > 16 || tag_len < 4 )
  348. return( MBEDTLS_ERR_GCM_BAD_INPUT );
  349. memcpy( tag, ctx->base_ectr, tag_len );
  350. if( orig_len || orig_add_len )
  351. {
  352. memset( work_buf, 0x00, 16 );
  353. PUT_UINT32_BE( ( orig_add_len >> 32 ), work_buf, 0 );
  354. PUT_UINT32_BE( ( orig_add_len ), work_buf, 4 );
  355. PUT_UINT32_BE( ( orig_len >> 32 ), work_buf, 8 );
  356. PUT_UINT32_BE( ( orig_len ), work_buf, 12 );
  357. for( i = 0; i < 16; i++ )
  358. ctx->buf[i] ^= work_buf[i];
  359. gcm_mult( ctx, ctx->buf, ctx->buf );
  360. for( i = 0; i < tag_len; i++ )
  361. tag[i] ^= ctx->buf[i];
  362. }
  363. return( 0 );
  364. }
  365. int mbedtls_gcm_crypt_and_tag( mbedtls_gcm_context *ctx,
  366. int mode,
  367. size_t length,
  368. const unsigned char *iv,
  369. size_t iv_len,
  370. const unsigned char *add,
  371. size_t add_len,
  372. const unsigned char *input,
  373. unsigned char *output,
  374. size_t tag_len,
  375. unsigned char *tag )
  376. {
  377. int ret;
  378. if( ( ret = mbedtls_gcm_starts( ctx, mode, iv, iv_len, add, add_len ) ) != 0 )
  379. return( ret );
  380. if( ( ret = mbedtls_gcm_update( ctx, length, input, output ) ) != 0 )
  381. return( ret );
  382. if( ( ret = mbedtls_gcm_finish( ctx, tag, tag_len ) ) != 0 )
  383. return( ret );
  384. return( 0 );
  385. }
  386. int mbedtls_gcm_auth_decrypt( mbedtls_gcm_context *ctx,
  387. size_t length,
  388. const unsigned char *iv,
  389. size_t iv_len,
  390. const unsigned char *add,
  391. size_t add_len,
  392. const unsigned char *tag,
  393. size_t tag_len,
  394. const unsigned char *input,
  395. unsigned char *output )
  396. {
  397. int ret;
  398. unsigned char check_tag[16];
  399. size_t i;
  400. int diff;
  401. if( ( ret = mbedtls_gcm_crypt_and_tag( ctx, MBEDTLS_GCM_DECRYPT, length,
  402. iv, iv_len, add, add_len,
  403. input, output, tag_len, check_tag ) ) != 0 )
  404. {
  405. return( ret );
  406. }
  407. /* Check tag in "constant-time" */
  408. for( diff = 0, i = 0; i < tag_len; i++ )
  409. diff |= tag[i] ^ check_tag[i];
  410. if( diff != 0 )
  411. {
  412. mbedtls_zeroize( output, length );
  413. return( MBEDTLS_ERR_GCM_AUTH_FAILED );
  414. }
  415. return( 0 );
  416. }
  417. void mbedtls_gcm_free( mbedtls_gcm_context *ctx )
  418. {
  419. mbedtls_cipher_free( &ctx->cipher_ctx );
  420. mbedtls_zeroize( ctx, sizeof( mbedtls_gcm_context ) );
  421. }
  422. #endif /* !MBEDTLS_GCM_ALT */
  423. #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
  424. /*
  425. * AES-GCM test vectors from:
  426. *
  427. * http://csrc.nist.gov/groups/STM/cavp/documents/mac/gcmtestvectors.zip
  428. */
  429. #define MAX_TESTS 6
  430. static const int key_index[MAX_TESTS] =
  431. { 0, 0, 1, 1, 1, 1 };
  432. static const unsigned char key[MAX_TESTS][32] =
  433. {
  434. { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  435. 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  436. 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  437. 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
  438. { 0xfe, 0xff, 0xe9, 0x92, 0x86, 0x65, 0x73, 0x1c,
  439. 0x6d, 0x6a, 0x8f, 0x94, 0x67, 0x30, 0x83, 0x08,
  440. 0xfe, 0xff, 0xe9, 0x92, 0x86, 0x65, 0x73, 0x1c,
  441. 0x6d, 0x6a, 0x8f, 0x94, 0x67, 0x30, 0x83, 0x08 },
  442. };
  443. static const size_t iv_len[MAX_TESTS] =
  444. { 12, 12, 12, 12, 8, 60 };
  445. static const int iv_index[MAX_TESTS] =
  446. { 0, 0, 1, 1, 1, 2 };
  447. static const unsigned char iv[MAX_TESTS][64] =
  448. {
  449. { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  450. 0x00, 0x00, 0x00, 0x00 },
  451. { 0xca, 0xfe, 0xba, 0xbe, 0xfa, 0xce, 0xdb, 0xad,
  452. 0xde, 0xca, 0xf8, 0x88 },
  453. { 0x93, 0x13, 0x22, 0x5d, 0xf8, 0x84, 0x06, 0xe5,
  454. 0x55, 0x90, 0x9c, 0x5a, 0xff, 0x52, 0x69, 0xaa,
  455. 0x6a, 0x7a, 0x95, 0x38, 0x53, 0x4f, 0x7d, 0xa1,
  456. 0xe4, 0xc3, 0x03, 0xd2, 0xa3, 0x18, 0xa7, 0x28,
  457. 0xc3, 0xc0, 0xc9, 0x51, 0x56, 0x80, 0x95, 0x39,
  458. 0xfc, 0xf0, 0xe2, 0x42, 0x9a, 0x6b, 0x52, 0x54,
  459. 0x16, 0xae, 0xdb, 0xf5, 0xa0, 0xde, 0x6a, 0x57,
  460. 0xa6, 0x37, 0xb3, 0x9b },
  461. };
  462. static const size_t add_len[MAX_TESTS] =
  463. { 0, 0, 0, 20, 20, 20 };
  464. static const int add_index[MAX_TESTS] =
  465. { 0, 0, 0, 1, 1, 1 };
  466. static const unsigned char additional[MAX_TESTS][64] =
  467. {
  468. { 0x00 },
  469. { 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef,
  470. 0xfe, 0xed, 0xfa, 0xce, 0xde, 0xad, 0xbe, 0xef,
  471. 0xab, 0xad, 0xda, 0xd2 },
  472. };
  473. static const size_t pt_len[MAX_TESTS] =
  474. { 0, 16, 64, 60, 60, 60 };
  475. static const int pt_index[MAX_TESTS] =
  476. { 0, 0, 1, 1, 1, 1 };
  477. static const unsigned char pt[MAX_TESTS][64] =
  478. {
  479. { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  480. 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
  481. { 0xd9, 0x31, 0x32, 0x25, 0xf8, 0x84, 0x06, 0xe5,
  482. 0xa5, 0x59, 0x09, 0xc5, 0xaf, 0xf5, 0x26, 0x9a,
  483. 0x86, 0xa7, 0xa9, 0x53, 0x15, 0x34, 0xf7, 0xda,
  484. 0x2e, 0x4c, 0x30, 0x3d, 0x8a, 0x31, 0x8a, 0x72,
  485. 0x1c, 0x3c, 0x0c, 0x95, 0x95, 0x68, 0x09, 0x53,
  486. 0x2f, 0xcf, 0x0e, 0x24, 0x49, 0xa6, 0xb5, 0x25,
  487. 0xb1, 0x6a, 0xed, 0xf5, 0xaa, 0x0d, 0xe6, 0x57,
  488. 0xba, 0x63, 0x7b, 0x39, 0x1a, 0xaf, 0xd2, 0x55 },
  489. };
  490. static const unsigned char ct[MAX_TESTS * 3][64] =
  491. {
  492. { 0x00 },
  493. { 0x03, 0x88, 0xda, 0xce, 0x60, 0xb6, 0xa3, 0x92,
  494. 0xf3, 0x28, 0xc2, 0xb9, 0x71, 0xb2, 0xfe, 0x78 },
  495. { 0x42, 0x83, 0x1e, 0xc2, 0x21, 0x77, 0x74, 0x24,
  496. 0x4b, 0x72, 0x21, 0xb7, 0x84, 0xd0, 0xd4, 0x9c,
  497. 0xe3, 0xaa, 0x21, 0x2f, 0x2c, 0x02, 0xa4, 0xe0,
  498. 0x35, 0xc1, 0x7e, 0x23, 0x29, 0xac, 0xa1, 0x2e,
  499. 0x21, 0xd5, 0x14, 0xb2, 0x54, 0x66, 0x93, 0x1c,
  500. 0x7d, 0x8f, 0x6a, 0x5a, 0xac, 0x84, 0xaa, 0x05,
  501. 0x1b, 0xa3, 0x0b, 0x39, 0x6a, 0x0a, 0xac, 0x97,
  502. 0x3d, 0x58, 0xe0, 0x91, 0x47, 0x3f, 0x59, 0x85 },
  503. { 0x42, 0x83, 0x1e, 0xc2, 0x21, 0x77, 0x74, 0x24,
  504. 0x4b, 0x72, 0x21, 0xb7, 0x84, 0xd0, 0xd4, 0x9c,
  505. 0xe3, 0xaa, 0x21, 0x2f, 0x2c, 0x02, 0xa4, 0xe0,
  506. 0x35, 0xc1, 0x7e, 0x23, 0x29, 0xac, 0xa1, 0x2e,
  507. 0x21, 0xd5, 0x14, 0xb2, 0x54, 0x66, 0x93, 0x1c,
  508. 0x7d, 0x8f, 0x6a, 0x5a, 0xac, 0x84, 0xaa, 0x05,
  509. 0x1b, 0xa3, 0x0b, 0x39, 0x6a, 0x0a, 0xac, 0x97,
  510. 0x3d, 0x58, 0xe0, 0x91 },
  511. { 0x61, 0x35, 0x3b, 0x4c, 0x28, 0x06, 0x93, 0x4a,
  512. 0x77, 0x7f, 0xf5, 0x1f, 0xa2, 0x2a, 0x47, 0x55,
  513. 0x69, 0x9b, 0x2a, 0x71, 0x4f, 0xcd, 0xc6, 0xf8,
  514. 0x37, 0x66, 0xe5, 0xf9, 0x7b, 0x6c, 0x74, 0x23,
  515. 0x73, 0x80, 0x69, 0x00, 0xe4, 0x9f, 0x24, 0xb2,
  516. 0x2b, 0x09, 0x75, 0x44, 0xd4, 0x89, 0x6b, 0x42,
  517. 0x49, 0x89, 0xb5, 0xe1, 0xeb, 0xac, 0x0f, 0x07,
  518. 0xc2, 0x3f, 0x45, 0x98 },
  519. { 0x8c, 0xe2, 0x49, 0x98, 0x62, 0x56, 0x15, 0xb6,
  520. 0x03, 0xa0, 0x33, 0xac, 0xa1, 0x3f, 0xb8, 0x94,
  521. 0xbe, 0x91, 0x12, 0xa5, 0xc3, 0xa2, 0x11, 0xa8,
  522. 0xba, 0x26, 0x2a, 0x3c, 0xca, 0x7e, 0x2c, 0xa7,
  523. 0x01, 0xe4, 0xa9, 0xa4, 0xfb, 0xa4, 0x3c, 0x90,
  524. 0xcc, 0xdc, 0xb2, 0x81, 0xd4, 0x8c, 0x7c, 0x6f,
  525. 0xd6, 0x28, 0x75, 0xd2, 0xac, 0xa4, 0x17, 0x03,
  526. 0x4c, 0x34, 0xae, 0xe5 },
  527. { 0x00 },
  528. { 0x98, 0xe7, 0x24, 0x7c, 0x07, 0xf0, 0xfe, 0x41,
  529. 0x1c, 0x26, 0x7e, 0x43, 0x84, 0xb0, 0xf6, 0x00 },
  530. { 0x39, 0x80, 0xca, 0x0b, 0x3c, 0x00, 0xe8, 0x41,
  531. 0xeb, 0x06, 0xfa, 0xc4, 0x87, 0x2a, 0x27, 0x57,
  532. 0x85, 0x9e, 0x1c, 0xea, 0xa6, 0xef, 0xd9, 0x84,
  533. 0x62, 0x85, 0x93, 0xb4, 0x0c, 0xa1, 0xe1, 0x9c,
  534. 0x7d, 0x77, 0x3d, 0x00, 0xc1, 0x44, 0xc5, 0x25,
  535. 0xac, 0x61, 0x9d, 0x18, 0xc8, 0x4a, 0x3f, 0x47,
  536. 0x18, 0xe2, 0x44, 0x8b, 0x2f, 0xe3, 0x24, 0xd9,
  537. 0xcc, 0xda, 0x27, 0x10, 0xac, 0xad, 0xe2, 0x56 },
  538. { 0x39, 0x80, 0xca, 0x0b, 0x3c, 0x00, 0xe8, 0x41,
  539. 0xeb, 0x06, 0xfa, 0xc4, 0x87, 0x2a, 0x27, 0x57,
  540. 0x85, 0x9e, 0x1c, 0xea, 0xa6, 0xef, 0xd9, 0x84,
  541. 0x62, 0x85, 0x93, 0xb4, 0x0c, 0xa1, 0xe1, 0x9c,
  542. 0x7d, 0x77, 0x3d, 0x00, 0xc1, 0x44, 0xc5, 0x25,
  543. 0xac, 0x61, 0x9d, 0x18, 0xc8, 0x4a, 0x3f, 0x47,
  544. 0x18, 0xe2, 0x44, 0x8b, 0x2f, 0xe3, 0x24, 0xd9,
  545. 0xcc, 0xda, 0x27, 0x10 },
  546. { 0x0f, 0x10, 0xf5, 0x99, 0xae, 0x14, 0xa1, 0x54,
  547. 0xed, 0x24, 0xb3, 0x6e, 0x25, 0x32, 0x4d, 0xb8,
  548. 0xc5, 0x66, 0x63, 0x2e, 0xf2, 0xbb, 0xb3, 0x4f,
  549. 0x83, 0x47, 0x28, 0x0f, 0xc4, 0x50, 0x70, 0x57,
  550. 0xfd, 0xdc, 0x29, 0xdf, 0x9a, 0x47, 0x1f, 0x75,
  551. 0xc6, 0x65, 0x41, 0xd4, 0xd4, 0xda, 0xd1, 0xc9,
  552. 0xe9, 0x3a, 0x19, 0xa5, 0x8e, 0x8b, 0x47, 0x3f,
  553. 0xa0, 0xf0, 0x62, 0xf7 },
  554. { 0xd2, 0x7e, 0x88, 0x68, 0x1c, 0xe3, 0x24, 0x3c,
  555. 0x48, 0x30, 0x16, 0x5a, 0x8f, 0xdc, 0xf9, 0xff,
  556. 0x1d, 0xe9, 0xa1, 0xd8, 0xe6, 0xb4, 0x47, 0xef,
  557. 0x6e, 0xf7, 0xb7, 0x98, 0x28, 0x66, 0x6e, 0x45,
  558. 0x81, 0xe7, 0x90, 0x12, 0xaf, 0x34, 0xdd, 0xd9,
  559. 0xe2, 0xf0, 0x37, 0x58, 0x9b, 0x29, 0x2d, 0xb3,
  560. 0xe6, 0x7c, 0x03, 0x67, 0x45, 0xfa, 0x22, 0xe7,
  561. 0xe9, 0xb7, 0x37, 0x3b },
  562. { 0x00 },
  563. { 0xce, 0xa7, 0x40, 0x3d, 0x4d, 0x60, 0x6b, 0x6e,
  564. 0x07, 0x4e, 0xc5, 0xd3, 0xba, 0xf3, 0x9d, 0x18 },
  565. { 0x52, 0x2d, 0xc1, 0xf0, 0x99, 0x56, 0x7d, 0x07,
  566. 0xf4, 0x7f, 0x37, 0xa3, 0x2a, 0x84, 0x42, 0x7d,
  567. 0x64, 0x3a, 0x8c, 0xdc, 0xbf, 0xe5, 0xc0, 0xc9,
  568. 0x75, 0x98, 0xa2, 0xbd, 0x25, 0x55, 0xd1, 0xaa,
  569. 0x8c, 0xb0, 0x8e, 0x48, 0x59, 0x0d, 0xbb, 0x3d,
  570. 0xa7, 0xb0, 0x8b, 0x10, 0x56, 0x82, 0x88, 0x38,
  571. 0xc5, 0xf6, 0x1e, 0x63, 0x93, 0xba, 0x7a, 0x0a,
  572. 0xbc, 0xc9, 0xf6, 0x62, 0x89, 0x80, 0x15, 0xad },
  573. { 0x52, 0x2d, 0xc1, 0xf0, 0x99, 0x56, 0x7d, 0x07,
  574. 0xf4, 0x7f, 0x37, 0xa3, 0x2a, 0x84, 0x42, 0x7d,
  575. 0x64, 0x3a, 0x8c, 0xdc, 0xbf, 0xe5, 0xc0, 0xc9,
  576. 0x75, 0x98, 0xa2, 0xbd, 0x25, 0x55, 0xd1, 0xaa,
  577. 0x8c, 0xb0, 0x8e, 0x48, 0x59, 0x0d, 0xbb, 0x3d,
  578. 0xa7, 0xb0, 0x8b, 0x10, 0x56, 0x82, 0x88, 0x38,
  579. 0xc5, 0xf6, 0x1e, 0x63, 0x93, 0xba, 0x7a, 0x0a,
  580. 0xbc, 0xc9, 0xf6, 0x62 },
  581. { 0xc3, 0x76, 0x2d, 0xf1, 0xca, 0x78, 0x7d, 0x32,
  582. 0xae, 0x47, 0xc1, 0x3b, 0xf1, 0x98, 0x44, 0xcb,
  583. 0xaf, 0x1a, 0xe1, 0x4d, 0x0b, 0x97, 0x6a, 0xfa,
  584. 0xc5, 0x2f, 0xf7, 0xd7, 0x9b, 0xba, 0x9d, 0xe0,
  585. 0xfe, 0xb5, 0x82, 0xd3, 0x39, 0x34, 0xa4, 0xf0,
  586. 0x95, 0x4c, 0xc2, 0x36, 0x3b, 0xc7, 0x3f, 0x78,
  587. 0x62, 0xac, 0x43, 0x0e, 0x64, 0xab, 0xe4, 0x99,
  588. 0xf4, 0x7c, 0x9b, 0x1f },
  589. { 0x5a, 0x8d, 0xef, 0x2f, 0x0c, 0x9e, 0x53, 0xf1,
  590. 0xf7, 0x5d, 0x78, 0x53, 0x65, 0x9e, 0x2a, 0x20,
  591. 0xee, 0xb2, 0xb2, 0x2a, 0xaf, 0xde, 0x64, 0x19,
  592. 0xa0, 0x58, 0xab, 0x4f, 0x6f, 0x74, 0x6b, 0xf4,
  593. 0x0f, 0xc0, 0xc3, 0xb7, 0x80, 0xf2, 0x44, 0x45,
  594. 0x2d, 0xa3, 0xeb, 0xf1, 0xc5, 0xd8, 0x2c, 0xde,
  595. 0xa2, 0x41, 0x89, 0x97, 0x20, 0x0e, 0xf8, 0x2e,
  596. 0x44, 0xae, 0x7e, 0x3f },
  597. };
  598. static const unsigned char tag[MAX_TESTS * 3][16] =
  599. {
  600. { 0x58, 0xe2, 0xfc, 0xce, 0xfa, 0x7e, 0x30, 0x61,
  601. 0x36, 0x7f, 0x1d, 0x57, 0xa4, 0xe7, 0x45, 0x5a },
  602. { 0xab, 0x6e, 0x47, 0xd4, 0x2c, 0xec, 0x13, 0xbd,
  603. 0xf5, 0x3a, 0x67, 0xb2, 0x12, 0x57, 0xbd, 0xdf },
  604. { 0x4d, 0x5c, 0x2a, 0xf3, 0x27, 0xcd, 0x64, 0xa6,
  605. 0x2c, 0xf3, 0x5a, 0xbd, 0x2b, 0xa6, 0xfa, 0xb4 },
  606. { 0x5b, 0xc9, 0x4f, 0xbc, 0x32, 0x21, 0xa5, 0xdb,
  607. 0x94, 0xfa, 0xe9, 0x5a, 0xe7, 0x12, 0x1a, 0x47 },
  608. { 0x36, 0x12, 0xd2, 0xe7, 0x9e, 0x3b, 0x07, 0x85,
  609. 0x56, 0x1b, 0xe1, 0x4a, 0xac, 0xa2, 0xfc, 0xcb },
  610. { 0x61, 0x9c, 0xc5, 0xae, 0xff, 0xfe, 0x0b, 0xfa,
  611. 0x46, 0x2a, 0xf4, 0x3c, 0x16, 0x99, 0xd0, 0x50 },
  612. { 0xcd, 0x33, 0xb2, 0x8a, 0xc7, 0x73, 0xf7, 0x4b,
  613. 0xa0, 0x0e, 0xd1, 0xf3, 0x12, 0x57, 0x24, 0x35 },
  614. { 0x2f, 0xf5, 0x8d, 0x80, 0x03, 0x39, 0x27, 0xab,
  615. 0x8e, 0xf4, 0xd4, 0x58, 0x75, 0x14, 0xf0, 0xfb },
  616. { 0x99, 0x24, 0xa7, 0xc8, 0x58, 0x73, 0x36, 0xbf,
  617. 0xb1, 0x18, 0x02, 0x4d, 0xb8, 0x67, 0x4a, 0x14 },
  618. { 0x25, 0x19, 0x49, 0x8e, 0x80, 0xf1, 0x47, 0x8f,
  619. 0x37, 0xba, 0x55, 0xbd, 0x6d, 0x27, 0x61, 0x8c },
  620. { 0x65, 0xdc, 0xc5, 0x7f, 0xcf, 0x62, 0x3a, 0x24,
  621. 0x09, 0x4f, 0xcc, 0xa4, 0x0d, 0x35, 0x33, 0xf8 },
  622. { 0xdc, 0xf5, 0x66, 0xff, 0x29, 0x1c, 0x25, 0xbb,
  623. 0xb8, 0x56, 0x8f, 0xc3, 0xd3, 0x76, 0xa6, 0xd9 },
  624. { 0x53, 0x0f, 0x8a, 0xfb, 0xc7, 0x45, 0x36, 0xb9,
  625. 0xa9, 0x63, 0xb4, 0xf1, 0xc4, 0xcb, 0x73, 0x8b },
  626. { 0xd0, 0xd1, 0xc8, 0xa7, 0x99, 0x99, 0x6b, 0xf0,
  627. 0x26, 0x5b, 0x98, 0xb5, 0xd4, 0x8a, 0xb9, 0x19 },
  628. { 0xb0, 0x94, 0xda, 0xc5, 0xd9, 0x34, 0x71, 0xbd,
  629. 0xec, 0x1a, 0x50, 0x22, 0x70, 0xe3, 0xcc, 0x6c },
  630. { 0x76, 0xfc, 0x6e, 0xce, 0x0f, 0x4e, 0x17, 0x68,
  631. 0xcd, 0xdf, 0x88, 0x53, 0xbb, 0x2d, 0x55, 0x1b },
  632. { 0x3a, 0x33, 0x7d, 0xbf, 0x46, 0xa7, 0x92, 0xc4,
  633. 0x5e, 0x45, 0x49, 0x13, 0xfe, 0x2e, 0xa8, 0xf2 },
  634. { 0xa4, 0x4a, 0x82, 0x66, 0xee, 0x1c, 0x8e, 0xb0,
  635. 0xc8, 0xb5, 0xd4, 0xcf, 0x5a, 0xe9, 0xf1, 0x9a },
  636. };
  637. int mbedtls_gcm_self_test( int verbose )
  638. {
  639. mbedtls_gcm_context ctx;
  640. unsigned char buf[64];
  641. unsigned char tag_buf[16];
  642. int i, j, ret;
  643. mbedtls_cipher_id_t cipher = MBEDTLS_CIPHER_ID_AES;
  644. for( j = 0; j < 3; j++ )
  645. {
  646. int key_len = 128 + 64 * j;
  647. for( i = 0; i < MAX_TESTS; i++ )
  648. {
  649. mbedtls_gcm_init( &ctx );
  650. if( verbose != 0 )
  651. mbedtls_printf( " AES-GCM-%3d #%d (%s): ",
  652. key_len, i, "enc" );
  653. ret = mbedtls_gcm_setkey( &ctx, cipher, key[key_index[i]],
  654. key_len );
  655. /*
  656. * AES-192 is an optional feature that may be unavailable when
  657. * there is an alternative underlying implementation i.e. when
  658. * MBEDTLS_AES_ALT is defined.
  659. */
  660. if( ret == MBEDTLS_ERR_AES_FEATURE_UNAVAILABLE && key_len == 192 )
  661. {
  662. mbedtls_printf( "skipped\n" );
  663. break;
  664. }
  665. else if( ret != 0 )
  666. {
  667. goto exit;
  668. }
  669. ret = mbedtls_gcm_crypt_and_tag( &ctx, MBEDTLS_GCM_ENCRYPT,
  670. pt_len[i],
  671. iv[iv_index[i]], iv_len[i],
  672. additional[add_index[i]], add_len[i],
  673. pt[pt_index[i]], buf, 16, tag_buf );
  674. if( ret != 0 )
  675. goto exit;
  676. if ( memcmp( buf, ct[j * 6 + i], pt_len[i] ) != 0 ||
  677. memcmp( tag_buf, tag[j * 6 + i], 16 ) != 0 )
  678. {
  679. ret = 1;
  680. goto exit;
  681. }
  682. mbedtls_gcm_free( &ctx );
  683. if( verbose != 0 )
  684. mbedtls_printf( "passed\n" );
  685. mbedtls_gcm_init( &ctx );
  686. if( verbose != 0 )
  687. mbedtls_printf( " AES-GCM-%3d #%d (%s): ",
  688. key_len, i, "dec" );
  689. ret = mbedtls_gcm_setkey( &ctx, cipher, key[key_index[i]],
  690. key_len );
  691. if( ret != 0 )
  692. goto exit;
  693. ret = mbedtls_gcm_crypt_and_tag( &ctx, MBEDTLS_GCM_DECRYPT,
  694. pt_len[i],
  695. iv[iv_index[i]], iv_len[i],
  696. additional[add_index[i]], add_len[i],
  697. ct[j * 6 + i], buf, 16, tag_buf );
  698. if( ret != 0 )
  699. goto exit;
  700. if( memcmp( buf, pt[pt_index[i]], pt_len[i] ) != 0 ||
  701. memcmp( tag_buf, tag[j * 6 + i], 16 ) != 0 )
  702. {
  703. ret = 1;
  704. goto exit;
  705. }
  706. mbedtls_gcm_free( &ctx );
  707. if( verbose != 0 )
  708. mbedtls_printf( "passed\n" );
  709. mbedtls_gcm_init( &ctx );
  710. if( verbose != 0 )
  711. mbedtls_printf( " AES-GCM-%3d #%d split (%s): ",
  712. key_len, i, "enc" );
  713. ret = mbedtls_gcm_setkey( &ctx, cipher, key[key_index[i]],
  714. key_len );
  715. if( ret != 0 )
  716. goto exit;
  717. ret = mbedtls_gcm_starts( &ctx, MBEDTLS_GCM_ENCRYPT,
  718. iv[iv_index[i]], iv_len[i],
  719. additional[add_index[i]], add_len[i] );
  720. if( ret != 0 )
  721. goto exit;
  722. if( pt_len[i] > 32 )
  723. {
  724. size_t rest_len = pt_len[i] - 32;
  725. ret = mbedtls_gcm_update( &ctx, 32, pt[pt_index[i]], buf );
  726. if( ret != 0 )
  727. goto exit;
  728. ret = mbedtls_gcm_update( &ctx, rest_len, pt[pt_index[i]] + 32,
  729. buf + 32 );
  730. if( ret != 0 )
  731. goto exit;
  732. }
  733. else
  734. {
  735. ret = mbedtls_gcm_update( &ctx, pt_len[i], pt[pt_index[i]], buf );
  736. if( ret != 0 )
  737. goto exit;
  738. }
  739. ret = mbedtls_gcm_finish( &ctx, tag_buf, 16 );
  740. if( ret != 0 )
  741. goto exit;
  742. if( memcmp( buf, ct[j * 6 + i], pt_len[i] ) != 0 ||
  743. memcmp( tag_buf, tag[j * 6 + i], 16 ) != 0 )
  744. {
  745. ret = 1;
  746. goto exit;
  747. }
  748. mbedtls_gcm_free( &ctx );
  749. if( verbose != 0 )
  750. mbedtls_printf( "passed\n" );
  751. mbedtls_gcm_init( &ctx );
  752. if( verbose != 0 )
  753. mbedtls_printf( " AES-GCM-%3d #%d split (%s): ",
  754. key_len, i, "dec" );
  755. ret = mbedtls_gcm_setkey( &ctx, cipher, key[key_index[i]],
  756. key_len );
  757. if( ret != 0 )
  758. goto exit;
  759. ret = mbedtls_gcm_starts( &ctx, MBEDTLS_GCM_DECRYPT,
  760. iv[iv_index[i]], iv_len[i],
  761. additional[add_index[i]], add_len[i] );
  762. if( ret != 0 )
  763. goto exit;
  764. if( pt_len[i] > 32 )
  765. {
  766. size_t rest_len = pt_len[i] - 32;
  767. ret = mbedtls_gcm_update( &ctx, 32, ct[j * 6 + i], buf );
  768. if( ret != 0 )
  769. goto exit;
  770. ret = mbedtls_gcm_update( &ctx, rest_len, ct[j * 6 + i] + 32,
  771. buf + 32 );
  772. if( ret != 0 )
  773. goto exit;
  774. }
  775. else
  776. {
  777. ret = mbedtls_gcm_update( &ctx, pt_len[i], ct[j * 6 + i],
  778. buf );
  779. if( ret != 0 )
  780. goto exit;
  781. }
  782. ret = mbedtls_gcm_finish( &ctx, tag_buf, 16 );
  783. if( ret != 0 )
  784. goto exit;
  785. if( memcmp( buf, pt[pt_index[i]], pt_len[i] ) != 0 ||
  786. memcmp( tag_buf, tag[j * 6 + i], 16 ) != 0 )
  787. {
  788. ret = 1;
  789. goto exit;
  790. }
  791. mbedtls_gcm_free( &ctx );
  792. if( verbose != 0 )
  793. mbedtls_printf( "passed\n" );
  794. }
  795. }
  796. if( verbose != 0 )
  797. mbedtls_printf( "\n" );
  798. ret = 0;
  799. exit:
  800. if( ret != 0 )
  801. {
  802. if( verbose != 0 )
  803. mbedtls_printf( "failed\n" );
  804. mbedtls_gcm_free( &ctx );
  805. }
  806. return( ret );
  807. }
  808. #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
  809. #endif /* MBEDTLS_GCM_C */