1 /* 2 * Copyright 2016-2025 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <stdlib.h> 11 #include "ssl_local.h" 12 #include "internal/ktls.h" 13 #include "record/record_local.h" 14 #include "internal/cryptlib.h" 15 #include "internal/ssl_unwrap.h" 16 #include <openssl/evp.h> 17 #include <openssl/kdf.h> 18 #include <openssl/core_names.h> 19 20 #define TLS13_MAX_LABEL_LEN 249 21 22 /* ASCII: "tls13 ", in hex for EBCDIC compatibility */ 23 static const unsigned char label_prefix[] = "\x74\x6C\x73\x31\x33\x20"; 24 25 /* 26 * Given a |secret|; a |label| of length |labellen|; and |data| of length 27 * |datalen| (e.g. typically a hash of the handshake messages), derive a new 28 * secret |outlen| bytes long and store it in the location pointed to be |out|. 29 * The |data| value may be zero length. Any errors will be treated as fatal if 30 * |fatal| is set. Returns 1 on success 0 on failure. 31 * If |raise_error| is set, ERR_raise is called on failure. 32 */ 33 int tls13_hkdf_expand_ex(OSSL_LIB_CTX *libctx, const char *propq, 34 const EVP_MD *md, 35 const unsigned char *secret, 36 const unsigned char *label, size_t labellen, 37 const unsigned char *data, size_t datalen, 38 unsigned char *out, size_t outlen, int raise_error) 39 { 40 EVP_KDF *kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_TLS1_3_KDF, propq); 41 EVP_KDF_CTX *kctx; 42 OSSL_PARAM params[7], *p = params; 43 int mode = EVP_PKEY_HKDEF_MODE_EXPAND_ONLY; 44 const char *mdname = EVP_MD_get0_name(md); 45 int ret; 46 size_t hashlen; 47 48 kctx = EVP_KDF_CTX_new(kdf); 49 EVP_KDF_free(kdf); 50 if (kctx == NULL) 51 return 0; 52 53 if (labellen > TLS13_MAX_LABEL_LEN) { 54 if (raise_error) 55 /* 56 * Probably we have been called from SSL_export_keying_material(), 57 * or SSL_export_keying_material_early(). 58 */ 59 ERR_raise(ERR_LIB_SSL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL); 60 61 EVP_KDF_CTX_free(kctx); 62 return 0; 63 } 64 65 if ((ret = EVP_MD_get_size(md)) <= 0) { 66 EVP_KDF_CTX_free(kctx); 67 if (raise_error) 68 ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR); 69 return 0; 70 } 71 hashlen = (size_t)ret; 72 73 *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode); 74 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, 75 (char *)mdname, 0); 76 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, 77 (unsigned char *)secret, hashlen); 78 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX, 79 (unsigned char *)label_prefix, 80 sizeof(label_prefix) - 1); 81 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL, 82 (unsigned char *)label, labellen); 83 if (data != NULL) 84 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_DATA, 85 (unsigned char *)data, 86 datalen); 87 *p++ = OSSL_PARAM_construct_end(); 88 89 ret = EVP_KDF_derive(kctx, out, outlen, params) <= 0; 90 EVP_KDF_CTX_free(kctx); 91 92 if (ret != 0) { 93 if (raise_error) 94 ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR); 95 } 96 97 return ret == 0; 98 } 99 100 int tls13_hkdf_expand(SSL_CONNECTION *s, const EVP_MD *md, 101 const unsigned char *secret, 102 const unsigned char *label, size_t labellen, 103 const unsigned char *data, size_t datalen, 104 unsigned char *out, size_t outlen, int fatal) 105 { 106 int ret; 107 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); 108 109 ret = tls13_hkdf_expand_ex(sctx->libctx, sctx->propq, md, 110 secret, label, labellen, data, datalen, 111 out, outlen, !fatal); 112 if (ret == 0 && fatal) 113 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 114 115 return ret; 116 } 117 118 /* 119 * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on 120 * success 0 on failure. 121 */ 122 int tls13_derive_key(SSL_CONNECTION *s, const EVP_MD *md, 123 const unsigned char *secret, 124 unsigned char *key, size_t keylen) 125 { 126 /* ASCII: "key", in hex for EBCDIC compatibility */ 127 static const unsigned char keylabel[] = "\x6B\x65\x79"; 128 129 return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1, 130 NULL, 0, key, keylen, 1); 131 } 132 133 /* 134 * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on 135 * success 0 on failure. 136 */ 137 int tls13_derive_iv(SSL_CONNECTION *s, const EVP_MD *md, 138 const unsigned char *secret, 139 unsigned char *iv, size_t ivlen) 140 { 141 /* ASCII: "iv", in hex for EBCDIC compatibility */ 142 static const unsigned char ivlabel[] = "\x69\x76"; 143 144 return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1, 145 NULL, 0, iv, ivlen, 1); 146 } 147 148 int tls13_derive_finishedkey(SSL_CONNECTION *s, const EVP_MD *md, 149 const unsigned char *secret, 150 unsigned char *fin, size_t finlen) 151 { 152 /* ASCII: "finished", in hex for EBCDIC compatibility */ 153 static const unsigned char finishedlabel[] = "\x66\x69\x6E\x69\x73\x68\x65\x64"; 154 155 return tls13_hkdf_expand(s, md, secret, finishedlabel, 156 sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1); 157 } 158 159 /* 160 * Given the previous secret |prevsecret| and a new input secret |insecret| of 161 * length |insecretlen|, generate a new secret and store it in the location 162 * pointed to by |outsecret|. Returns 1 on success 0 on failure. 163 */ 164 int tls13_generate_secret(SSL_CONNECTION *s, const EVP_MD *md, 165 const unsigned char *prevsecret, 166 const unsigned char *insecret, 167 size_t insecretlen, 168 unsigned char *outsecret) 169 { 170 size_t mdlen; 171 int mdleni; 172 int ret; 173 EVP_KDF *kdf; 174 EVP_KDF_CTX *kctx; 175 OSSL_PARAM params[7], *p = params; 176 int mode = EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY; 177 const char *mdname = EVP_MD_get0_name(md); 178 /* ASCII: "derived", in hex for EBCDIC compatibility */ 179 static const char derived_secret_label[] = "\x64\x65\x72\x69\x76\x65\x64"; 180 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); 181 182 kdf = EVP_KDF_fetch(sctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF, sctx->propq); 183 kctx = EVP_KDF_CTX_new(kdf); 184 EVP_KDF_free(kdf); 185 if (kctx == NULL) { 186 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 187 return 0; 188 } 189 190 mdleni = EVP_MD_get_size(md); 191 /* Ensure cast to size_t is safe */ 192 if (!ossl_assert(mdleni > 0)) { 193 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 194 EVP_KDF_CTX_free(kctx); 195 return 0; 196 } 197 mdlen = (size_t)mdleni; 198 199 *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode); 200 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, 201 (char *)mdname, 0); 202 if (insecret != NULL) 203 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, 204 (unsigned char *)insecret, 205 insecretlen); 206 if (prevsecret != NULL) 207 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, 208 (unsigned char *)prevsecret, mdlen); 209 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX, 210 (unsigned char *)label_prefix, 211 sizeof(label_prefix) - 1); 212 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL, 213 (unsigned char *)derived_secret_label, 214 sizeof(derived_secret_label) - 1); 215 *p++ = OSSL_PARAM_construct_end(); 216 217 ret = EVP_KDF_derive(kctx, outsecret, mdlen, params) <= 0; 218 219 if (ret != 0) 220 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 221 222 EVP_KDF_CTX_free(kctx); 223 return ret == 0; 224 } 225 226 /* 227 * Given an input secret |insecret| of length |insecretlen| generate the 228 * handshake secret. This requires the early secret to already have been 229 * generated. Returns 1 on success 0 on failure. 230 */ 231 int tls13_generate_handshake_secret(SSL_CONNECTION *s, 232 const unsigned char *insecret, 233 size_t insecretlen) 234 { 235 /* Calls SSLfatal() if required */ 236 return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret, 237 insecret, insecretlen, 238 (unsigned char *)&s->handshake_secret); 239 } 240 241 /* 242 * Given the handshake secret |prev| of length |prevlen| generate the master 243 * secret and store its length in |*secret_size|. Returns 1 on success 0 on 244 * failure. 245 */ 246 int tls13_generate_master_secret(SSL_CONNECTION *s, unsigned char *out, 247 unsigned char *prev, size_t prevlen, 248 size_t *secret_size) 249 { 250 const EVP_MD *md = ssl_handshake_md(s); 251 int md_size; 252 253 md_size = EVP_MD_get_size(md); 254 if (md_size <= 0) { 255 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 256 return 0; 257 } 258 *secret_size = (size_t)md_size; 259 /* Calls SSLfatal() if required */ 260 return tls13_generate_secret(s, md, prev, NULL, 0, out); 261 } 262 263 /* 264 * Generates the mac for the Finished message. Returns the length of the MAC or 265 * 0 on error. 266 */ 267 size_t tls13_final_finish_mac(SSL_CONNECTION *s, const char *str, size_t slen, 268 unsigned char *out) 269 { 270 const EVP_MD *md = ssl_handshake_md(s); 271 const char *mdname = EVP_MD_get0_name(md); 272 unsigned char hash[EVP_MAX_MD_SIZE]; 273 unsigned char finsecret[EVP_MAX_MD_SIZE]; 274 unsigned char *key = NULL; 275 size_t len = 0, hashlen; 276 OSSL_PARAM params[2], *p = params; 277 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); 278 279 if (md == NULL) 280 return 0; 281 282 /* Safe to cast away const here since we're not "getting" any data */ 283 if (sctx->propq != NULL) 284 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_PROPERTIES, 285 (char *)sctx->propq, 286 0); 287 *p = OSSL_PARAM_construct_end(); 288 289 if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) { 290 /* SSLfatal() already called */ 291 goto err; 292 } 293 294 if (str == SSL_CONNECTION_GET_SSL(s)->method->ssl3_enc->server_finished_label) { 295 key = s->server_finished_secret; 296 } else if (SSL_IS_FIRST_HANDSHAKE(s)) { 297 key = s->client_finished_secret; 298 } else { 299 if (!tls13_derive_finishedkey(s, md, 300 s->client_app_traffic_secret, 301 finsecret, hashlen)) 302 goto err; 303 key = finsecret; 304 } 305 306 if (!EVP_Q_mac(sctx->libctx, "HMAC", sctx->propq, mdname, 307 params, key, hashlen, hash, hashlen, 308 /* outsize as per sizeof(peer_finish_md) */ 309 out, EVP_MAX_MD_SIZE * 2, &len)) { 310 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 311 goto err; 312 } 313 314 err: 315 OPENSSL_cleanse(finsecret, sizeof(finsecret)); 316 return len; 317 } 318 319 /* 320 * There isn't really a key block in TLSv1.3, but we still need this function 321 * for initialising the cipher and hash. Returns 1 on success or 0 on failure. 322 */ 323 int tls13_setup_key_block(SSL_CONNECTION *s) 324 { 325 const EVP_CIPHER *c; 326 const EVP_MD *hash; 327 int mac_type = NID_undef; 328 size_t mac_secret_size = 0; 329 330 s->session->cipher = s->s3.tmp.new_cipher; 331 if (!ssl_cipher_get_evp(SSL_CONNECTION_GET_CTX(s), s->session, &c, &hash, 332 &mac_type, &mac_secret_size, NULL, 0)) { 333 /* Error is already recorded */ 334 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR); 335 return 0; 336 } 337 338 ssl_evp_cipher_free(s->s3.tmp.new_sym_enc); 339 s->s3.tmp.new_sym_enc = c; 340 ssl_evp_md_free(s->s3.tmp.new_hash); 341 s->s3.tmp.new_hash = hash; 342 s->s3.tmp.new_mac_pkey_type = mac_type; 343 s->s3.tmp.new_mac_secret_size = mac_secret_size; 344 345 return 1; 346 } 347 348 static int derive_secret_key_and_iv(SSL_CONNECTION *s, const EVP_MD *md, 349 const EVP_CIPHER *ciph, 350 int mac_type, 351 const EVP_MD *mac_md, 352 const unsigned char *insecret, 353 const unsigned char *hash, 354 const unsigned char *label, 355 size_t labellen, unsigned char *secret, 356 unsigned char *key, size_t *keylen, 357 unsigned char **iv, size_t *ivlen, 358 size_t *taglen) 359 { 360 int hashleni = EVP_MD_get_size(md); 361 size_t hashlen; 362 int mode, mac_mdleni; 363 364 /* Ensure cast to size_t is safe */ 365 if (!ossl_assert(hashleni > 0)) { 366 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); 367 return 0; 368 } 369 hashlen = (size_t)hashleni; 370 371 if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen, 372 secret, hashlen, 1)) { 373 /* SSLfatal() already called */ 374 return 0; 375 } 376 377 /* if ciph is NULL cipher, then use new_hash to calculate keylen */ 378 if (EVP_CIPHER_is_a(ciph, "NULL") 379 && mac_md != NULL 380 && mac_type == NID_hmac) { 381 mac_mdleni = EVP_MD_get_size(mac_md); 382 383 if (mac_mdleni <= 0) { 384 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 385 return 0; 386 } 387 *ivlen = *taglen = (size_t)mac_mdleni; 388 *keylen = s->s3.tmp.new_mac_secret_size; 389 } else { 390 391 *keylen = EVP_CIPHER_get_key_length(ciph); 392 393 mode = EVP_CIPHER_get_mode(ciph); 394 if (mode == EVP_CIPH_CCM_MODE) { 395 uint32_t algenc; 396 397 *ivlen = EVP_CCM_TLS_IV_LEN; 398 if (s->s3.tmp.new_cipher != NULL) { 399 algenc = s->s3.tmp.new_cipher->algorithm_enc; 400 } else if (s->session->cipher != NULL) { 401 /* We've not selected a cipher yet - we must be doing early data */ 402 algenc = s->session->cipher->algorithm_enc; 403 } else if (s->psksession != NULL && s->psksession->cipher != NULL) { 404 /* We must be doing early data with out-of-band PSK */ 405 algenc = s->psksession->cipher->algorithm_enc; 406 } else { 407 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); 408 return 0; 409 } 410 if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8)) 411 *taglen = EVP_CCM8_TLS_TAG_LEN; 412 else 413 *taglen = EVP_CCM_TLS_TAG_LEN; 414 } else { 415 int iivlen; 416 417 if (mode == EVP_CIPH_GCM_MODE) { 418 *taglen = EVP_GCM_TLS_TAG_LEN; 419 } else { 420 /* CHACHA20P-POLY1305 */ 421 *taglen = EVP_CHACHAPOLY_TLS_TAG_LEN; 422 } 423 iivlen = EVP_CIPHER_get_iv_length(ciph); 424 if (iivlen < 0) { 425 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); 426 return 0; 427 } 428 *ivlen = iivlen; 429 } 430 } 431 432 if (*ivlen > EVP_MAX_IV_LENGTH) { 433 *iv = OPENSSL_malloc(*ivlen); 434 if (*iv == NULL) { 435 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE); 436 return 0; 437 } 438 } 439 440 if (!tls13_derive_key(s, md, secret, key, *keylen) 441 || !tls13_derive_iv(s, md, secret, *iv, *ivlen)) { 442 /* SSLfatal() already called */ 443 return 0; 444 } 445 446 return 1; 447 } 448 449 static int tls13_store_hash(SSL_CONNECTION *s, unsigned char *hash, size_t len) 450 { 451 size_t hashlen; 452 453 if (!ssl3_digest_cached_records(s, 1) 454 || !ssl_handshake_hash(s, hash, len, &hashlen)) { 455 /* SSLfatal() already called */; 456 return 0; 457 } 458 459 return 1; 460 } 461 462 int tls13_store_handshake_traffic_hash(SSL_CONNECTION *s) 463 { 464 return tls13_store_hash(s, s->handshake_traffic_hash, 465 sizeof(s->handshake_traffic_hash)); 466 } 467 468 int tls13_store_server_finished_hash(SSL_CONNECTION *s) 469 { 470 return tls13_store_hash(s, s->server_finished_hash, 471 sizeof(s->server_finished_hash)); 472 } 473 474 int tls13_change_cipher_state(SSL_CONNECTION *s, int which) 475 { 476 /* ASCII: "c e traffic", in hex for EBCDIC compatibility */ 477 static const unsigned char client_early_traffic[] = "\x63\x20\x65\x20\x74\x72\x61\x66\x66\x69\x63"; 478 /* ASCII: "c hs traffic", in hex for EBCDIC compatibility */ 479 static const unsigned char client_handshake_traffic[] = "\x63\x20\x68\x73\x20\x74\x72\x61\x66\x66\x69\x63"; 480 /* ASCII: "c ap traffic", in hex for EBCDIC compatibility */ 481 static const unsigned char client_application_traffic[] = "\x63\x20\x61\x70\x20\x74\x72\x61\x66\x66\x69\x63"; 482 /* ASCII: "s hs traffic", in hex for EBCDIC compatibility */ 483 static const unsigned char server_handshake_traffic[] = "\x73\x20\x68\x73\x20\x74\x72\x61\x66\x66\x69\x63"; 484 /* ASCII: "s ap traffic", in hex for EBCDIC compatibility */ 485 static const unsigned char server_application_traffic[] = "\x73\x20\x61\x70\x20\x74\x72\x61\x66\x66\x69\x63"; 486 /* ASCII: "exp master", in hex for EBCDIC compatibility */ 487 static const unsigned char exporter_master_secret[] = "\x65\x78\x70\x20\x6D\x61\x73\x74\x65\x72"; 488 /* ASCII: "res master", in hex for EBCDIC compatibility */ 489 static const unsigned char resumption_master_secret[] = "\x72\x65\x73\x20\x6D\x61\x73\x74\x65\x72"; 490 /* ASCII: "e exp master", in hex for EBCDIC compatibility */ 491 static const unsigned char early_exporter_master_secret[] = "\x65\x20\x65\x78\x70\x20\x6D\x61\x73\x74\x65\x72"; 492 unsigned char iv_intern[EVP_MAX_IV_LENGTH]; 493 unsigned char *iv = iv_intern; 494 unsigned char key[EVP_MAX_KEY_LENGTH]; 495 unsigned char secret[EVP_MAX_MD_SIZE]; 496 unsigned char hashval[EVP_MAX_MD_SIZE]; 497 unsigned char *hash = hashval; 498 unsigned char *insecret; 499 unsigned char *finsecret = NULL; 500 const char *log_label = NULL; 501 int finsecretlen = 0; 502 const unsigned char *label; 503 size_t labellen, hashlen = 0; 504 int ret = 0; 505 const EVP_MD *md = NULL, *mac_md = NULL; 506 const EVP_CIPHER *cipher = NULL; 507 int mac_pkey_type = NID_undef; 508 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); 509 size_t keylen, ivlen = EVP_MAX_IV_LENGTH, taglen; 510 int level; 511 int direction = (which & SSL3_CC_READ) != 0 ? OSSL_RECORD_DIRECTION_READ 512 : OSSL_RECORD_DIRECTION_WRITE; 513 514 if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE)) 515 || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) { 516 if ((which & SSL3_CC_EARLY) != 0) { 517 EVP_MD_CTX *mdctx = NULL; 518 long handlen; 519 void *hdata; 520 unsigned int hashlenui; 521 const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session); 522 523 insecret = s->early_secret; 524 label = client_early_traffic; 525 labellen = sizeof(client_early_traffic) - 1; 526 log_label = CLIENT_EARLY_LABEL; 527 528 handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata); 529 if (handlen <= 0) { 530 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH); 531 goto err; 532 } 533 534 if (s->early_data_state == SSL_EARLY_DATA_CONNECTING 535 && s->max_early_data > 0 536 && s->session->ext.max_early_data == 0) { 537 /* 538 * If we are attempting to send early data, and we've decided to 539 * actually do it but max_early_data in s->session is 0 then we 540 * must be using an external PSK. 541 */ 542 if (!ossl_assert(s->psksession != NULL 543 && s->max_early_data == s->psksession->ext.max_early_data)) { 544 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 545 goto err; 546 } 547 sslcipher = SSL_SESSION_get0_cipher(s->psksession); 548 } 549 if (sslcipher == NULL) { 550 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK); 551 goto err; 552 } 553 554 /* 555 * This ups the ref count on cipher so we better make sure we free 556 * it again 557 */ 558 if (!ssl_cipher_get_evp_cipher(sctx, sslcipher, &cipher)) { 559 /* Error is already recorded */ 560 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR); 561 goto err; 562 } 563 564 if (((EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) == 0) 565 && (!ssl_cipher_get_evp_md_mac(sctx, sslcipher, &mac_md, 566 &mac_pkey_type, NULL))) { 567 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR); 568 goto err; 569 } 570 571 /* 572 * We need to calculate the handshake digest using the digest from 573 * the session. We haven't yet selected our ciphersuite so we can't 574 * use ssl_handshake_md(). 575 */ 576 mdctx = EVP_MD_CTX_new(); 577 if (mdctx == NULL) { 578 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); 579 goto err; 580 } 581 582 md = ssl_md(sctx, sslcipher->algorithm2); 583 if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL) 584 || !EVP_DigestUpdate(mdctx, hdata, handlen) 585 || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) { 586 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 587 EVP_MD_CTX_free(mdctx); 588 goto err; 589 } 590 hashlen = hashlenui; 591 EVP_MD_CTX_free(mdctx); 592 593 if (!tls13_hkdf_expand(s, md, insecret, 594 early_exporter_master_secret, 595 sizeof(early_exporter_master_secret) - 1, 596 hashval, hashlen, 597 s->early_exporter_master_secret, hashlen, 598 1)) { 599 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 600 goto err; 601 } 602 603 if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL, 604 s->early_exporter_master_secret, hashlen)) { 605 /* SSLfatal() already called */ 606 goto err; 607 } 608 } else if (which & SSL3_CC_HANDSHAKE) { 609 insecret = s->handshake_secret; 610 finsecret = s->client_finished_secret; 611 finsecretlen = EVP_MD_get_size(ssl_handshake_md(s)); 612 if (finsecretlen <= 0) { 613 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 614 goto err; 615 } 616 label = client_handshake_traffic; 617 labellen = sizeof(client_handshake_traffic) - 1; 618 log_label = CLIENT_HANDSHAKE_LABEL; 619 /* 620 * The handshake hash used for the server read/client write handshake 621 * traffic secret is the same as the hash for the server 622 * write/client read handshake traffic secret. However, if we 623 * processed early data then we delay changing the server 624 * read/client write cipher state until later, and the handshake 625 * hashes have moved on. Therefore we use the value saved earlier 626 * when we did the server write/client read change cipher state. 627 */ 628 hash = s->handshake_traffic_hash; 629 } else { 630 insecret = s->master_secret; 631 label = client_application_traffic; 632 labellen = sizeof(client_application_traffic) - 1; 633 log_label = CLIENT_APPLICATION_LABEL; 634 /* 635 * For this we only use the handshake hashes up until the server 636 * Finished hash. We do not include the client's Finished, which is 637 * what ssl_handshake_hash() would give us. Instead we use the 638 * previously saved value. 639 */ 640 hash = s->server_finished_hash; 641 } 642 } else { 643 /* Early data never applies to client-read/server-write */ 644 if (which & SSL3_CC_HANDSHAKE) { 645 insecret = s->handshake_secret; 646 finsecret = s->server_finished_secret; 647 finsecretlen = EVP_MD_get_size(ssl_handshake_md(s)); 648 if (finsecretlen <= 0) { 649 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 650 goto err; 651 } 652 label = server_handshake_traffic; 653 labellen = sizeof(server_handshake_traffic) - 1; 654 log_label = SERVER_HANDSHAKE_LABEL; 655 } else { 656 insecret = s->master_secret; 657 label = server_application_traffic; 658 labellen = sizeof(server_application_traffic) - 1; 659 log_label = SERVER_APPLICATION_LABEL; 660 hash = s->server_finished_hash; 661 } 662 } 663 664 if ((which & SSL3_CC_EARLY) == 0) { 665 md = ssl_handshake_md(s); 666 cipher = s->s3.tmp.new_sym_enc; 667 mac_md = s->s3.tmp.new_hash; 668 mac_pkey_type = s->s3.tmp.new_mac_pkey_type; 669 if (!ssl3_digest_cached_records(s, 1) 670 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) { 671 /* SSLfatal() already called */; 672 goto err; 673 } 674 } 675 676 if (label == client_application_traffic) { 677 /* 678 * We also create the resumption master secret, but this time use the 679 * hash for the whole handshake including the Client Finished 680 */ 681 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret, 682 resumption_master_secret, 683 sizeof(resumption_master_secret) - 1, 684 hashval, hashlen, s->resumption_master_secret, 685 hashlen, 1)) { 686 /* SSLfatal() already called */ 687 goto err; 688 } 689 } 690 691 /* check whether cipher is known */ 692 if (!ossl_assert(cipher != NULL)) 693 goto err; 694 695 if (!derive_secret_key_and_iv(s, md, cipher, mac_pkey_type, mac_md, 696 insecret, hash, label, labellen, secret, key, 697 &keylen, &iv, &ivlen, &taglen)) { 698 /* SSLfatal() already called */ 699 goto err; 700 } 701 702 if (label == server_application_traffic) { 703 memcpy(s->server_app_traffic_secret, secret, hashlen); 704 /* Now we create the exporter master secret */ 705 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret, 706 exporter_master_secret, 707 sizeof(exporter_master_secret) - 1, 708 hash, hashlen, s->exporter_master_secret, 709 hashlen, 1)) { 710 /* SSLfatal() already called */ 711 goto err; 712 } 713 714 if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret, 715 hashlen)) { 716 /* SSLfatal() already called */ 717 goto err; 718 } 719 } else if (label == client_application_traffic) 720 memcpy(s->client_app_traffic_secret, secret, hashlen); 721 722 if (!ssl_log_secret(s, log_label, secret, hashlen)) { 723 /* SSLfatal() already called */ 724 goto err; 725 } 726 727 if (finsecret != NULL 728 && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret, 729 finsecret, (size_t)finsecretlen)) { 730 /* SSLfatal() already called */ 731 goto err; 732 } 733 734 if ((which & SSL3_CC_WRITE) != 0) { 735 if (!s->server && label == client_early_traffic) 736 s->rlayer.wrlmethod->set_plain_alerts(s->rlayer.wrl, 1); 737 else 738 s->rlayer.wrlmethod->set_plain_alerts(s->rlayer.wrl, 0); 739 } 740 741 level = (which & SSL3_CC_EARLY) != 0 742 ? OSSL_RECORD_PROTECTION_LEVEL_EARLY 743 : ((which & SSL3_CC_HANDSHAKE) != 0 744 ? OSSL_RECORD_PROTECTION_LEVEL_HANDSHAKE 745 : OSSL_RECORD_PROTECTION_LEVEL_APPLICATION); 746 747 if (!ssl_set_new_record_layer(s, s->version, 748 direction, 749 level, secret, hashlen, key, keylen, iv, 750 ivlen, NULL, 0, cipher, taglen, 751 mac_pkey_type, mac_md, NULL, md)) { 752 /* SSLfatal already called */ 753 goto err; 754 } 755 756 ret = 1; 757 err: 758 if ((which & SSL3_CC_EARLY) != 0) { 759 /* We up-refed this so now we need to down ref */ 760 if ((EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) == 0) 761 ssl_evp_md_free(mac_md); 762 ssl_evp_cipher_free(cipher); 763 } 764 OPENSSL_cleanse(key, sizeof(key)); 765 OPENSSL_cleanse(secret, sizeof(secret)); 766 if (iv != iv_intern) 767 OPENSSL_free(iv); 768 return ret; 769 } 770 771 int tls13_update_key(SSL_CONNECTION *s, int sending) 772 { 773 /* ASCII: "traffic upd", in hex for EBCDIC compatibility */ 774 static const unsigned char application_traffic[] = "\x74\x72\x61\x66\x66\x69\x63\x20\x75\x70\x64"; 775 const EVP_MD *md = ssl_handshake_md(s); 776 size_t hashlen; 777 unsigned char key[EVP_MAX_KEY_LENGTH]; 778 unsigned char *insecret; 779 unsigned char secret[EVP_MAX_MD_SIZE]; 780 char *log_label; 781 size_t keylen, ivlen, taglen; 782 int ret = 0, l; 783 int direction = sending ? OSSL_RECORD_DIRECTION_WRITE 784 : OSSL_RECORD_DIRECTION_READ; 785 unsigned char iv_intern[EVP_MAX_IV_LENGTH]; 786 unsigned char *iv = iv_intern; 787 788 if ((l = EVP_MD_get_size(md)) <= 0) { 789 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 790 return 0; 791 } 792 hashlen = (size_t)l; 793 794 if (s->server == sending) 795 insecret = s->server_app_traffic_secret; 796 else 797 insecret = s->client_app_traffic_secret; 798 799 if (!derive_secret_key_and_iv(s, md, 800 s->s3.tmp.new_sym_enc, 801 s->s3.tmp.new_mac_pkey_type, s->s3.tmp.new_hash, 802 insecret, NULL, 803 application_traffic, 804 sizeof(application_traffic) - 1, secret, key, 805 &keylen, &iv, &ivlen, &taglen)) { 806 /* SSLfatal() already called */ 807 goto err; 808 } 809 810 memcpy(insecret, secret, hashlen); 811 812 if (!ssl_set_new_record_layer(s, s->version, 813 direction, 814 OSSL_RECORD_PROTECTION_LEVEL_APPLICATION, 815 insecret, hashlen, key, keylen, iv, ivlen, NULL, 0, 816 s->s3.tmp.new_sym_enc, taglen, NID_undef, NULL, 817 NULL, md)) { 818 /* SSLfatal already called */ 819 goto err; 820 } 821 822 /* Call Key log on successful traffic secret update */ 823 log_label = s->server == sending ? SERVER_APPLICATION_N_LABEL : CLIENT_APPLICATION_N_LABEL; 824 if (!ssl_log_secret(s, log_label, secret, hashlen)) { 825 /* SSLfatal() already called */ 826 goto err; 827 } 828 ret = 1; 829 err: 830 OPENSSL_cleanse(key, sizeof(key)); 831 OPENSSL_cleanse(secret, sizeof(secret)); 832 if (iv != iv_intern) 833 OPENSSL_free(iv); 834 return ret; 835 } 836 837 int tls13_alert_code(int code) 838 { 839 /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */ 840 if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED) 841 return code; 842 843 return tls1_alert_code(code); 844 } 845 846 int tls13_export_keying_material(SSL_CONNECTION *s, 847 unsigned char *out, size_t olen, 848 const char *label, size_t llen, 849 const unsigned char *context, 850 size_t contextlen, int use_context) 851 { 852 unsigned char exportsecret[EVP_MAX_MD_SIZE]; 853 /* ASCII: "exporter", in hex for EBCDIC compatibility */ 854 static const unsigned char exporterlabel[] = "\x65\x78\x70\x6F\x72\x74\x65\x72"; 855 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE]; 856 const EVP_MD *md = ssl_handshake_md(s); 857 EVP_MD_CTX *ctx = EVP_MD_CTX_new(); 858 unsigned int hashsize, datalen; 859 int ret = 0; 860 861 if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s)) 862 goto err; 863 864 if (!use_context) 865 contextlen = 0; 866 867 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0 868 || EVP_DigestUpdate(ctx, context, contextlen) <= 0 869 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0 870 || EVP_DigestInit_ex(ctx, md, NULL) <= 0 871 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0 872 || !tls13_hkdf_expand(s, md, s->exporter_master_secret, 873 (const unsigned char *)label, llen, 874 data, datalen, exportsecret, hashsize, 0) 875 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel, 876 sizeof(exporterlabel) - 1, hash, hashsize, 877 out, olen, 0)) 878 goto err; 879 880 ret = 1; 881 err: 882 EVP_MD_CTX_free(ctx); 883 return ret; 884 } 885 886 int tls13_export_keying_material_early(SSL_CONNECTION *s, 887 unsigned char *out, size_t olen, 888 const char *label, size_t llen, 889 const unsigned char *context, 890 size_t contextlen) 891 { 892 /* ASCII: "exporter", in hex for EBCDIC compatibility */ 893 static const unsigned char exporterlabel[] = "\x65\x78\x70\x6F\x72\x74\x65\x72"; 894 unsigned char exportsecret[EVP_MAX_MD_SIZE]; 895 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE]; 896 const EVP_MD *md; 897 EVP_MD_CTX *ctx = EVP_MD_CTX_new(); 898 unsigned int hashsize, datalen; 899 int ret = 0; 900 const SSL_CIPHER *sslcipher; 901 902 if (ctx == NULL || !ossl_statem_export_early_allowed(s)) 903 goto err; 904 905 if (!s->server && s->max_early_data > 0 906 && s->session->ext.max_early_data == 0) 907 sslcipher = SSL_SESSION_get0_cipher(s->psksession); 908 else 909 sslcipher = SSL_SESSION_get0_cipher(s->session); 910 911 md = ssl_md(SSL_CONNECTION_GET_CTX(s), sslcipher->algorithm2); 912 913 /* 914 * Calculate the hash value and store it in |data|. The reason why 915 * the empty string is used is that the definition of TLS-Exporter 916 * is like so: 917 * 918 * TLS-Exporter(label, context_value, key_length) = 919 * HKDF-Expand-Label(Derive-Secret(Secret, label, ""), 920 * "exporter", Hash(context_value), key_length) 921 * 922 * Derive-Secret(Secret, Label, Messages) = 923 * HKDF-Expand-Label(Secret, Label, 924 * Transcript-Hash(Messages), Hash.length) 925 * 926 * Here Transcript-Hash is the cipher suite hash algorithm. 927 */ 928 if (md == NULL 929 || EVP_DigestInit_ex(ctx, md, NULL) <= 0 930 || EVP_DigestUpdate(ctx, context, contextlen) <= 0 931 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0 932 || EVP_DigestInit_ex(ctx, md, NULL) <= 0 933 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0 934 || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret, 935 (const unsigned char *)label, llen, 936 data, datalen, exportsecret, hashsize, 0) 937 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel, 938 sizeof(exporterlabel) - 1, hash, hashsize, 939 out, olen, 0)) 940 goto err; 941 942 ret = 1; 943 err: 944 EVP_MD_CTX_free(ctx); 945 return ret; 946 } 947
Indexes created Sat Feb 28 05:31:39 UTC 2026