ssl/t1_enc.c

   1 /*
   2  * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright 2005 Nokia. All rights reserved.
   4  *
   5  * Licensed under the Apache License 2.0 (the "License").  You may not use
   6  * this file except in compliance with the License.  You can obtain a copy
   7  * in the file LICENSE in the source distribution or at
   8  * https://www.openssl.org/source/license.html
   9  */
  10
  11 #include <stdio.h>
  12 #include "ssl_locl.h"
  13 #include "record/record_locl.h"
  14 #include "internal/ktls.h"
  15 #include "internal/cryptlib.h"
  16 #include <openssl/comp.h>
  17 #include <openssl/evp.h>
  18 #include <openssl/kdf.h>
  19 #include <openssl/rand.h>
  20 #include <openssl/obj_mac.h>
  21
  22 /* seed1 through seed5 are concatenated */
  23 static int tls1_PRF(SSL *s,
  24                     const void *seed1, size_t seed1_len,
  25                     const void *seed2, size_t seed2_len,
  26                     const void *seed3, size_t seed3_len,
  27                     const void *seed4, size_t seed4_len,
  28                     const void *seed5, size_t seed5_len,
  29                     const unsigned char *sec, size_t slen,
  30                     unsigned char *out, size_t olen, int fatal)
  31 {
  32     const EVP_MD *md = ssl_prf_md(s);
  33     EVP_PKEY_CTX *pctx = NULL;
  34     int ret = 0;
  35
  36     if (md == NULL) {
  37         /* Should never happen */
  38         if (fatal)
  39             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_PRF,
  40                      ERR_R_INTERNAL_ERROR);
  41         else
  42             SSLerr(SSL_F_TLS1_PRF, ERR_R_INTERNAL_ERROR);
  43         return 0;
  44     }
  45     pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_TLS1_PRF, NULL);
  46     if (pctx == NULL || EVP_PKEY_derive_init(pctx) <= 0
  47         || EVP_PKEY_CTX_set_tls1_prf_md(pctx, md) <= 0
  48         || EVP_PKEY_CTX_set1_tls1_prf_secret(pctx, sec, (int)slen) <= 0
  49         || EVP_PKEY_CTX_add1_tls1_prf_seed(pctx, seed1, (int)seed1_len) <= 0
  50         || EVP_PKEY_CTX_add1_tls1_prf_seed(pctx, seed2, (int)seed2_len) <= 0
  51         || EVP_PKEY_CTX_add1_tls1_prf_seed(pctx, seed3, (int)seed3_len) <= 0
  52         || EVP_PKEY_CTX_add1_tls1_prf_seed(pctx, seed4, (int)seed4_len) <= 0
  53         || EVP_PKEY_CTX_add1_tls1_prf_seed(pctx, seed5, (int)seed5_len) <= 0
  54         || EVP_PKEY_derive(pctx, out, &olen) <= 0) {
  55         if (fatal)
  56             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_PRF,
  57                      ERR_R_INTERNAL_ERROR);
  58         else
  59             SSLerr(SSL_F_TLS1_PRF, ERR_R_INTERNAL_ERROR);
  60         goto err;
  61     }
  62
  63     ret = 1;
  64
  65  err:
  66     EVP_PKEY_CTX_free(pctx);
  67     return ret;
  68 }
  69
  70 static int tls1_generate_key_block(SSL *s, unsigned char *km, size_t num)
  71 {
  72     int ret;
  73
  74     /* Calls SSLfatal() as required */
  75     ret = tls1_PRF(s,
  76                    TLS_MD_KEY_EXPANSION_CONST,
  77                    TLS_MD_KEY_EXPANSION_CONST_SIZE, s->s3->server_random,
  78                    SSL3_RANDOM_SIZE, s->s3->client_random, SSL3_RANDOM_SIZE,
  79                    NULL, 0, NULL, 0, s->session->master_key,
  80                    s->session->master_key_length, km, num, 1);
  81
  82     return ret;
  83 }
  84
  85 int tls1_change_cipher_state(SSL *s, int which)
  86 {
  87     unsigned char *p, *mac_secret;
  88     unsigned char *ms, *key, *iv;
  89     EVP_CIPHER_CTX *dd;
  90     const EVP_CIPHER *c;
  91 #ifndef OPENSSL_NO_COMP
  92     const SSL_COMP *comp;
  93 #endif
  94     const EVP_MD *m;
  95     int mac_type;
  96     size_t *mac_secret_size;
  97     EVP_MD_CTX *mac_ctx;
  98     EVP_PKEY *mac_key;
  99     size_t n, i, j, k, cl;
 100     int reuse_dd = 0;
 101 #ifndef OPENSSL_NO_KTLS
 102     struct tls12_crypto_info_aes_gcm_128 crypto_info;
 103     BIO *wbio;
 104     unsigned char geniv[12];
 105 #endif
 106
 107     c = s->s3->tmp.new_sym_enc;
 108     m = s->s3->tmp.new_hash;
 109     mac_type = s->s3->tmp.new_mac_pkey_type;
 110 #ifndef OPENSSL_NO_COMP
 111     comp = s->s3->tmp.new_compression;
 112 #endif
 113
 114     if (which & SSL3_CC_READ) {
 115         if (s->ext.use_etm)
 116             s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC_READ;
 117         else
 118             s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC_READ;
 119
 120         if (s->s3->tmp.new_cipher->algorithm2 & TLS1_STREAM_MAC)
 121             s->mac_flags |= SSL_MAC_FLAG_READ_MAC_STREAM;
 122         else
 123             s->mac_flags &= ~SSL_MAC_FLAG_READ_MAC_STREAM;
 124
 125         if (s->enc_read_ctx != NULL) {
 126             reuse_dd = 1;
 127         } else if ((s->enc_read_ctx = EVP_CIPHER_CTX_new()) == NULL) {
 128             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 129                      ERR_R_MALLOC_FAILURE);
 130             goto err;
 131         } else {
 132             /*
 133              * make sure it's initialised in case we exit later with an error
 134              */
 135             EVP_CIPHER_CTX_reset(s->enc_read_ctx);
 136         }
 137         dd = s->enc_read_ctx;
 138         mac_ctx = ssl_replace_hash(&s->read_hash, NULL);
 139         if (mac_ctx == NULL) {
 140             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 141                      ERR_R_INTERNAL_ERROR);
 142             goto err;
 143         }
 144 #ifndef OPENSSL_NO_COMP
 145         COMP_CTX_free(s->expand);
 146         s->expand = NULL;
 147         if (comp != NULL) {
 148             s->expand = COMP_CTX_new(comp->method);
 149             if (s->expand == NULL) {
 150                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 151                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 152                          SSL_R_COMPRESSION_LIBRARY_ERROR);
 153                 goto err;
 154             }
 155         }
 156 #endif
 157         /*
 158          * this is done by dtls1_reset_seq_numbers for DTLS
 159          */
 160         if (!SSL_IS_DTLS(s))
 161             RECORD_LAYER_reset_read_sequence(&s->rlayer);
 162         mac_secret = &(s->s3->read_mac_secret[0]);
 163         mac_secret_size = &(s->s3->read_mac_secret_size);
 164     } else {
 165         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
 166         if (s->ext.use_etm)
 167             s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC_WRITE;
 168         else
 169             s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC_WRITE;
 170
 171         if (s->s3->tmp.new_cipher->algorithm2 & TLS1_STREAM_MAC)
 172             s->mac_flags |= SSL_MAC_FLAG_WRITE_MAC_STREAM;
 173         else
 174             s->mac_flags &= ~SSL_MAC_FLAG_WRITE_MAC_STREAM;
 175         if (s->enc_write_ctx != NULL && !SSL_IS_DTLS(s)) {
 176             reuse_dd = 1;
 177         } else if ((s->enc_write_ctx = EVP_CIPHER_CTX_new()) == NULL) {
 178             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 179                      ERR_R_MALLOC_FAILURE);
 180             goto err;
 181         }
 182         dd = s->enc_write_ctx;
 183         if (SSL_IS_DTLS(s)) {
 184             mac_ctx = EVP_MD_CTX_new();
 185             if (mac_ctx == NULL) {
 186                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 187                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 188                          ERR_R_MALLOC_FAILURE);
 189                 goto err;
 190             }
 191             s->write_hash = mac_ctx;
 192         } else {
 193             mac_ctx = ssl_replace_hash(&s->write_hash, NULL);
 194             if (mac_ctx == NULL) {
 195                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 196                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 197                          ERR_R_MALLOC_FAILURE);
 198                 goto err;
 199             }
 200         }
 201 #ifndef OPENSSL_NO_COMP
 202         COMP_CTX_free(s->compress);
 203         s->compress = NULL;
 204         if (comp != NULL) {
 205             s->compress = COMP_CTX_new(comp->method);
 206             if (s->compress == NULL) {
 207                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 208                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 209                         SSL_R_COMPRESSION_LIBRARY_ERROR);
 210                 goto err;
 211             }
 212         }
 213 #endif
 214         /*
 215          * this is done by dtls1_reset_seq_numbers for DTLS
 216          */
 217         if (!SSL_IS_DTLS(s))
 218             RECORD_LAYER_reset_write_sequence(&s->rlayer);
 219         mac_secret = &(s->s3->write_mac_secret[0]);
 220         mac_secret_size = &(s->s3->write_mac_secret_size);
 221     }
 222
 223     if (reuse_dd)
 224         EVP_CIPHER_CTX_reset(dd);
 225
 226     p = s->s3->tmp.key_block;
 227     i = *mac_secret_size = s->s3->tmp.new_mac_secret_size;
 228
 229     /* TODO(size_t): convert me */
 230     cl = EVP_CIPHER_key_length(c);
 231     j = cl;
 232     /* Was j=(exp)?5:EVP_CIPHER_key_length(c); */
 233     /* If GCM/CCM mode only part of IV comes from PRF */
 234     if (EVP_CIPHER_mode(c) == EVP_CIPH_GCM_MODE)
 235         k = EVP_GCM_TLS_FIXED_IV_LEN;
 236     else if (EVP_CIPHER_mode(c) == EVP_CIPH_CCM_MODE)
 237         k = EVP_CCM_TLS_FIXED_IV_LEN;
 238     else
 239         k = EVP_CIPHER_iv_length(c);
 240     if ((which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
 241         (which == SSL3_CHANGE_CIPHER_SERVER_READ)) {
 242         ms = &(p[0]);
 243         n = i + i;
 244         key = &(p[n]);
 245         n += j + j;
 246         iv = &(p[n]);
 247         n += k + k;
 248     } else {
 249         n = i;
 250         ms = &(p[n]);
 251         n += i + j;
 252         key = &(p[n]);
 253         n += j + k;
 254         iv = &(p[n]);
 255         n += k;
 256     }
 257
 258     if (n > s->s3->tmp.key_block_length) {
 259         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 260                  ERR_R_INTERNAL_ERROR);
 261         goto err;
 262     }
 263
 264     memcpy(mac_secret, ms, i);
 265
 266     if (!(EVP_CIPHER_flags(c) & EVP_CIPH_FLAG_AEAD_CIPHER)) {
 267         /* TODO(size_t): Convert this function */
 268         mac_key = EVP_PKEY_new_mac_key(mac_type, NULL, mac_secret,
 269                                                (int)*mac_secret_size);
 270         if (mac_key == NULL
 271             || EVP_DigestSignInit(mac_ctx, NULL, m, NULL, mac_key) <= 0) {
 272             EVP_PKEY_free(mac_key);
 273             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 274                      ERR_R_INTERNAL_ERROR);
 275             goto err;
 276         }
 277         EVP_PKEY_free(mac_key);
 278     }
 279 #ifdef SSL_DEBUG
 280     printf("which = %04X\nmac key=", which);
 281     {
 282         size_t z;
 283         for (z = 0; z < i; z++)
 284             printf("%02X%c", ms[z], ((z + 1) % 16) ? ' ' : '\n');
 285     }
 286 #endif
 287
 288     if (EVP_CIPHER_mode(c) == EVP_CIPH_GCM_MODE) {
 289         if (!EVP_CipherInit_ex(dd, c, NULL, key, NULL, (which & SSL3_CC_WRITE))
 290             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_GCM_SET_IV_FIXED, (int)k,
 291                                     iv)) {
 292             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 293                      ERR_R_INTERNAL_ERROR);
 294             goto err;
 295         }
 296     } else if (EVP_CIPHER_mode(c) == EVP_CIPH_CCM_MODE) {
 297         int taglen;
 298         if (s->s3->tmp.
 299             new_cipher->algorithm_enc & (SSL_AES128CCM8 | SSL_AES256CCM8))
 300             taglen = EVP_CCM8_TLS_TAG_LEN;
 301         else
 302             taglen = EVP_CCM_TLS_TAG_LEN;
 303         if (!EVP_CipherInit_ex(dd, c, NULL, NULL, NULL, (which & SSL3_CC_WRITE))
 304             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_AEAD_SET_IVLEN, 12, NULL)
 305             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_AEAD_SET_TAG, taglen, NULL)
 306             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_CCM_SET_IV_FIXED, (int)k, iv)
 307             || !EVP_CipherInit_ex(dd, NULL, NULL, key, NULL, -1)) {
 308             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 309                      ERR_R_INTERNAL_ERROR);
 310             goto err;
 311         }
 312     } else {
 313         if (!EVP_CipherInit_ex(dd, c, NULL, key, iv, (which & SSL3_CC_WRITE))) {
 314             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 315                      ERR_R_INTERNAL_ERROR);
 316             goto err;
 317         }
 318     }
 319     /* Needed for "composite" AEADs, such as RC4-HMAC-MD5 */
 320     if ((EVP_CIPHER_flags(c) & EVP_CIPH_FLAG_AEAD_CIPHER) && *mac_secret_size
 321         && !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_AEAD_SET_MAC_KEY,
 322                                 (int)*mac_secret_size, mac_secret)) {
 323         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 324                  ERR_R_INTERNAL_ERROR);
 325         goto err;
 326     }
 327 #ifndef OPENSSL_NO_KTLS
 328     if (s->compress)
 329         goto skip_ktls;
 330
 331     if ((which & SSL3_CC_READ) ||
 332         ((which & SSL3_CC_WRITE) && (s->mode & SSL_MODE_NO_KTLS_TX)))
 333         goto skip_ktls;
 334
 335     /* ktls supports only the maximum fragment size */
 336     if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
 337         goto skip_ktls;
 338
 339     /* check that cipher is AES_GCM_128 */
 340     if (EVP_CIPHER_nid(c) != NID_aes_128_gcm
 341         || EVP_CIPHER_mode(c) != EVP_CIPH_GCM_MODE
 342         || EVP_CIPHER_key_length(c) != TLS_CIPHER_AES_GCM_128_KEY_SIZE)
 343         goto skip_ktls;
 344
 345     /* check version is 1.2 */
 346     if (s->version != TLS1_2_VERSION)
 347         goto skip_ktls;
 348
 349     wbio = s->wbio;
 350     if (!ossl_assert(wbio != NULL)) {
 351         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 352                  ERR_R_INTERNAL_ERROR);
 353         goto err;
 354     }
 355
 356     /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
 357     if (BIO_flush(wbio) <= 0)
 358         goto skip_ktls;
 359
 360     /* ktls doesn't support renegotiation */
 361     if (BIO_get_ktls_send(s->wbio)) {
 362         SSLfatal(s, SSL_AD_NO_RENEGOTIATION, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 363                  ERR_R_INTERNAL_ERROR);
 364         goto err;
 365     }
 366
 367     memset(&crypto_info, 0, sizeof(crypto_info));
 368     crypto_info.info.cipher_type = TLS_CIPHER_AES_GCM_128;
 369     crypto_info.info.version = s->version;
 370
 371     EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_GET_IV,
 372                         EVP_GCM_TLS_FIXED_IV_LEN + EVP_GCM_TLS_EXPLICIT_IV_LEN,
 373                         geniv);
 374     memcpy(crypto_info.iv, geniv + EVP_GCM_TLS_FIXED_IV_LEN,
 375            TLS_CIPHER_AES_GCM_128_IV_SIZE);
 376     memcpy(crypto_info.salt, geniv, TLS_CIPHER_AES_GCM_128_SALT_SIZE);
 377     memcpy(crypto_info.key, key, EVP_CIPHER_key_length(c));
 378     memcpy(crypto_info.rec_seq, &s->rlayer.write_sequence,
 379            TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
 380
 381     /* ktls works with user provided buffers directly */
 382     if (BIO_set_ktls(wbio, &crypto_info, which & SSL3_CC_WRITE)) {
 383         ssl3_release_write_buffer(s);
 384         SSL_set_options(s, SSL_OP_NO_RENEGOTIATION);
 385     }
 386
 387  skip_ktls:
 388 #endif                          /* OPENSSL_NO_KTLS */
 389     s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
 390
 391 #ifdef SSL_DEBUG
 392     printf("which = %04X\nkey=", which);
 393     {
 394         int z;
 395         for (z = 0; z < EVP_CIPHER_key_length(c); z++)
 396             printf("%02X%c", key[z], ((z + 1) % 16) ? ' ' : '\n');
 397     }
 398     printf("\niv=");
 399     {
 400         size_t z;
 401         for (z = 0; z < k; z++)
 402             printf("%02X%c", iv[z], ((z + 1) % 16) ? ' ' : '\n');
 403     }
 404     printf("\n");
 405 #endif
 406
 407     return 1;
 408  err:
 409     return 0;
 410 }
 411
 412 int tls1_setup_key_block(SSL *s)
 413 {
 414     unsigned char *p;
 415     const EVP_CIPHER *c;
 416     const EVP_MD *hash;
 417     SSL_COMP *comp;
 418     int mac_type = NID_undef;
 419     size_t num, mac_secret_size = 0;
 420     int ret = 0;
 421
 422     if (s->s3->tmp.key_block_length != 0)
 423         return 1;
 424
 425     if (!ssl_cipher_get_evp(s->session, &c, &hash, &mac_type, &mac_secret_size,
 426                             &comp, s->ext.use_etm)) {
 427         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_SETUP_KEY_BLOCK,
 428                  SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
 429         return 0;
 430     }
 431
 432     s->s3->tmp.new_sym_enc = c;
 433     s->s3->tmp.new_hash = hash;
 434     s->s3->tmp.new_mac_pkey_type = mac_type;
 435     s->s3->tmp.new_mac_secret_size = mac_secret_size;
 436     num = EVP_CIPHER_key_length(c) + mac_secret_size + EVP_CIPHER_iv_length(c);
 437     num *= 2;
 438
 439     ssl3_cleanup_key_block(s);
 440
 441     if ((p = OPENSSL_malloc(num)) == NULL) {
 442         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_SETUP_KEY_BLOCK,
 443                  ERR_R_MALLOC_FAILURE);
 444         goto err;
 445     }
 446
 447     s->s3->tmp.key_block_length = num;
 448     s->s3->tmp.key_block = p;
 449
 450 #ifdef SSL_DEBUG
 451     printf("client random\n");
 452     {
 453         int z;
 454         for (z = 0; z < SSL3_RANDOM_SIZE; z++)
 455             printf("%02X%c", s->s3->client_random[z],
 456                    ((z + 1) % 16) ? ' ' : '\n');
 457     }
 458     printf("server random\n");
 459     {
 460         int z;
 461         for (z = 0; z < SSL3_RANDOM_SIZE; z++)
 462             printf("%02X%c", s->s3->server_random[z],
 463                    ((z + 1) % 16) ? ' ' : '\n');
 464     }
 465     printf("master key\n");
 466     {
 467         size_t z;
 468         for (z = 0; z < s->session->master_key_length; z++)
 469             printf("%02X%c", s->session->master_key[z],
 470                    ((z + 1) % 16) ? ' ' : '\n');
 471     }
 472 #endif
 473     if (!tls1_generate_key_block(s, p, num)) {
 474         /* SSLfatal() already called */
 475         goto err;
 476     }
 477 #ifdef SSL_DEBUG
 478     printf("\nkey block\n");
 479     {
 480         size_t z;
 481         for (z = 0; z < num; z++)
 482             printf("%02X%c", p[z], ((z + 1) % 16) ? ' ' : '\n');
 483     }
 484 #endif
 485
 486     if (!(s->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS)
 487         && s->method->version <= TLS1_VERSION) {
 488         /*
 489          * enable vulnerability countermeasure for CBC ciphers with known-IV
 490          * problem (http://www.openssl.org/~bodo/tls-cbc.txt)
 491          */
 492         s->s3->need_empty_fragments = 1;
 493
 494         if (s->session->cipher != NULL) {
 495             if (s->session->cipher->algorithm_enc == SSL_eNULL)
 496                 s->s3->need_empty_fragments = 0;
 497
 498 #ifndef OPENSSL_NO_RC4
 499             if (s->session->cipher->algorithm_enc == SSL_RC4)
 500                 s->s3->need_empty_fragments = 0;
 501 #endif
 502         }
 503     }
 504
 505     ret = 1;
 506  err:
 507     return ret;
 508 }
 509
 510 size_t tls1_final_finish_mac(SSL *s, const char *str, size_t slen,
 511                              unsigned char *out)
 512 {
 513     size_t hashlen;
 514     unsigned char hash[EVP_MAX_MD_SIZE];
 515
 516     if (!ssl3_digest_cached_records(s, 0)) {
 517         /* SSLfatal() already called */
 518         return 0;
 519     }
 520
 521     if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
 522         /* SSLfatal() already called */
 523         return 0;
 524     }
 525
 526     if (!tls1_PRF(s, str, slen, hash, hashlen, NULL, 0, NULL, 0, NULL, 0,
 527                   s->session->master_key, s->session->master_key_length,
 528                   out, TLS1_FINISH_MAC_LENGTH, 1)) {
 529         /* SSLfatal() already called */
 530         return 0;
 531     }
 532     OPENSSL_cleanse(hash, hashlen);
 533     return TLS1_FINISH_MAC_LENGTH;
 534 }
 535
 536 int tls1_generate_master_secret(SSL *s, unsigned char *out, unsigned char *p,
 537                                 size_t len, size_t *secret_size)
 538 {
 539     if (s->session->flags & SSL_SESS_FLAG_EXTMS) {
 540         unsigned char hash[EVP_MAX_MD_SIZE * 2];
 541         size_t hashlen;
 542         /*
 543          * Digest cached records keeping record buffer (if present): this wont
 544          * affect client auth because we're freezing the buffer at the same
 545          * point (after client key exchange and before certificate verify)
 546          */
 547         if (!ssl3_digest_cached_records(s, 1)
 548                 || !ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
 549             /* SSLfatal() already called */
 550             return 0;
 551         }
 552 #ifdef SSL_DEBUG
 553         fprintf(stderr, "Handshake hashes:\n");
 554         BIO_dump_fp(stderr, (char *)hash, hashlen);
 555 #endif
 556         if (!tls1_PRF(s,
 557                       TLS_MD_EXTENDED_MASTER_SECRET_CONST,
 558                       TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE,
 559                       hash, hashlen,
 560                       NULL, 0,
 561                       NULL, 0,
 562                       NULL, 0, p, len, out,
 563                       SSL3_MASTER_SECRET_SIZE, 1)) {
 564             /* SSLfatal() already called */
 565             return 0;
 566         }
 567         OPENSSL_cleanse(hash, hashlen);
 568     } else {
 569         if (!tls1_PRF(s,
 570                       TLS_MD_MASTER_SECRET_CONST,
 571                       TLS_MD_MASTER_SECRET_CONST_SIZE,
 572                       s->s3->client_random, SSL3_RANDOM_SIZE,
 573                       NULL, 0,
 574                       s->s3->server_random, SSL3_RANDOM_SIZE,
 575                       NULL, 0, p, len, out,
 576                       SSL3_MASTER_SECRET_SIZE, 1)) {
 577            /* SSLfatal() already called */
 578             return 0;
 579         }
 580     }
 581 #ifdef SSL_DEBUG
 582     fprintf(stderr, "Premaster Secret:\n");
 583     BIO_dump_fp(stderr, (char *)p, len);
 584     fprintf(stderr, "Client Random:\n");
 585     BIO_dump_fp(stderr, (char *)s->s3->client_random, SSL3_RANDOM_SIZE);
 586     fprintf(stderr, "Server Random:\n");
 587     BIO_dump_fp(stderr, (char *)s->s3->server_random, SSL3_RANDOM_SIZE);
 588     fprintf(stderr, "Master Secret:\n");
 589     BIO_dump_fp(stderr, (char *)s->session->master_key,
 590                 SSL3_MASTER_SECRET_SIZE);
 591 #endif
 592
 593     *secret_size = SSL3_MASTER_SECRET_SIZE;
 594     return 1;
 595 }
 596
 597 int tls1_export_keying_material(SSL *s, unsigned char *out, size_t olen,
 598                                 const char *label, size_t llen,
 599                                 const unsigned char *context,
 600                                 size_t contextlen, int use_context)
 601 {
 602     unsigned char *val = NULL;
 603     size_t vallen = 0, currentvalpos;
 604     int rv;
 605
 606     /*
 607      * construct PRF arguments we construct the PRF argument ourself rather
 608      * than passing separate values into the TLS PRF to ensure that the
 609      * concatenation of values does not create a prohibited label.
 610      */
 611     vallen = llen + SSL3_RANDOM_SIZE * 2;
 612     if (use_context) {
 613         vallen += 2 + contextlen;
 614     }
 615
 616     val = OPENSSL_malloc(vallen);
 617     if (val == NULL)
 618         goto err2;
 619     currentvalpos = 0;
 620     memcpy(val + currentvalpos, (unsigned char *)label, llen);
 621     currentvalpos += llen;
 622     memcpy(val + currentvalpos, s->s3->client_random, SSL3_RANDOM_SIZE);
 623     currentvalpos += SSL3_RANDOM_SIZE;
 624     memcpy(val + currentvalpos, s->s3->server_random, SSL3_RANDOM_SIZE);
 625     currentvalpos += SSL3_RANDOM_SIZE;
 626
 627     if (use_context) {
 628         val[currentvalpos] = (contextlen >> 8) & 0xff;
 629         currentvalpos++;
 630         val[currentvalpos] = contextlen & 0xff;
 631         currentvalpos++;
 632         if ((contextlen > 0) || (context != NULL)) {
 633             memcpy(val + currentvalpos, context, contextlen);
 634         }
 635     }
 636
 637     /*
 638      * disallow prohibited labels note that SSL3_RANDOM_SIZE > max(prohibited
 639      * label len) = 15, so size of val > max(prohibited label len) = 15 and
 640      * the comparisons won't have buffer overflow
 641      */
 642     if (memcmp(val, TLS_MD_CLIENT_FINISH_CONST,
 643                TLS_MD_CLIENT_FINISH_CONST_SIZE) == 0)
 644         goto err1;
 645     if (memcmp(val, TLS_MD_SERVER_FINISH_CONST,
 646                TLS_MD_SERVER_FINISH_CONST_SIZE) == 0)
 647         goto err1;
 648     if (memcmp(val, TLS_MD_MASTER_SECRET_CONST,
 649                TLS_MD_MASTER_SECRET_CONST_SIZE) == 0)
 650         goto err1;
 651     if (memcmp(val, TLS_MD_EXTENDED_MASTER_SECRET_CONST,
 652                TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE) == 0)
 653         goto err1;
 654     if (memcmp(val, TLS_MD_KEY_EXPANSION_CONST,
 655                TLS_MD_KEY_EXPANSION_CONST_SIZE) == 0)
 656         goto err1;
 657
 658     rv = tls1_PRF(s,
 659                   val, vallen,
 660                   NULL, 0,
 661                   NULL, 0,
 662                   NULL, 0,
 663                   NULL, 0,
 664                   s->session->master_key, s->session->master_key_length,
 665                   out, olen, 0);
 666
 667     goto ret;
 668  err1:
 669     SSLerr(SSL_F_TLS1_EXPORT_KEYING_MATERIAL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
 670     rv = 0;
 671     goto ret;
 672  err2:
 673     SSLerr(SSL_F_TLS1_EXPORT_KEYING_MATERIAL, ERR_R_MALLOC_FAILURE);
 674     rv = 0;
 675  ret:
 676     OPENSSL_clear_free(val, vallen);
 677     return rv;
 678 }
 679
 680 int tls1_alert_code(int code)
 681 {
 682     switch (code) {
 683     case SSL_AD_CLOSE_NOTIFY:
 684         return SSL3_AD_CLOSE_NOTIFY;
 685     case SSL_AD_UNEXPECTED_MESSAGE:
 686         return SSL3_AD_UNEXPECTED_MESSAGE;
 687     case SSL_AD_BAD_RECORD_MAC:
 688         return SSL3_AD_BAD_RECORD_MAC;
 689     case SSL_AD_DECRYPTION_FAILED:
 690         return TLS1_AD_DECRYPTION_FAILED;
 691     case SSL_AD_RECORD_OVERFLOW:
 692         return TLS1_AD_RECORD_OVERFLOW;
 693     case SSL_AD_DECOMPRESSION_FAILURE:
 694         return SSL3_AD_DECOMPRESSION_FAILURE;
 695     case SSL_AD_HANDSHAKE_FAILURE:
 696         return SSL3_AD_HANDSHAKE_FAILURE;
 697     case SSL_AD_NO_CERTIFICATE:
 698         return -1;
 699     case SSL_AD_BAD_CERTIFICATE:
 700         return SSL3_AD_BAD_CERTIFICATE;
 701     case SSL_AD_UNSUPPORTED_CERTIFICATE:
 702         return SSL3_AD_UNSUPPORTED_CERTIFICATE;
 703     case SSL_AD_CERTIFICATE_REVOKED:
 704         return SSL3_AD_CERTIFICATE_REVOKED;
 705     case SSL_AD_CERTIFICATE_EXPIRED:
 706         return SSL3_AD_CERTIFICATE_EXPIRED;
 707     case SSL_AD_CERTIFICATE_UNKNOWN:
 708         return SSL3_AD_CERTIFICATE_UNKNOWN;
 709     case SSL_AD_ILLEGAL_PARAMETER:
 710         return SSL3_AD_ILLEGAL_PARAMETER;
 711     case SSL_AD_UNKNOWN_CA:
 712         return TLS1_AD_UNKNOWN_CA;
 713     case SSL_AD_ACCESS_DENIED:
 714         return TLS1_AD_ACCESS_DENIED;
 715     case SSL_AD_DECODE_ERROR:
 716         return TLS1_AD_DECODE_ERROR;
 717     case SSL_AD_DECRYPT_ERROR:
 718         return TLS1_AD_DECRYPT_ERROR;
 719     case SSL_AD_EXPORT_RESTRICTION:
 720         return TLS1_AD_EXPORT_RESTRICTION;
 721     case SSL_AD_PROTOCOL_VERSION:
 722         return TLS1_AD_PROTOCOL_VERSION;
 723     case SSL_AD_INSUFFICIENT_SECURITY:
 724         return TLS1_AD_INSUFFICIENT_SECURITY;
 725     case SSL_AD_INTERNAL_ERROR:
 726         return TLS1_AD_INTERNAL_ERROR;
 727     case SSL_AD_USER_CANCELLED:
 728         return TLS1_AD_USER_CANCELLED;
 729     case SSL_AD_NO_RENEGOTIATION:
 730         return TLS1_AD_NO_RENEGOTIATION;
 731     case SSL_AD_UNSUPPORTED_EXTENSION:
 732         return TLS1_AD_UNSUPPORTED_EXTENSION;
 733     case SSL_AD_CERTIFICATE_UNOBTAINABLE:
 734         return TLS1_AD_CERTIFICATE_UNOBTAINABLE;
 735     case SSL_AD_UNRECOGNIZED_NAME:
 736         return TLS1_AD_UNRECOGNIZED_NAME;
 737     case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
 738         return TLS1_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
 739     case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
 740         return TLS1_AD_BAD_CERTIFICATE_HASH_VALUE;
 741     case SSL_AD_UNKNOWN_PSK_IDENTITY:
 742         return TLS1_AD_UNKNOWN_PSK_IDENTITY;
 743     case SSL_AD_INAPPROPRIATE_FALLBACK:
 744         return TLS1_AD_INAPPROPRIATE_FALLBACK;
 745     case SSL_AD_NO_APPLICATION_PROTOCOL:
 746         return TLS1_AD_NO_APPLICATION_PROTOCOL;
 747     case SSL_AD_CERTIFICATE_REQUIRED:
 748         return SSL_AD_HANDSHAKE_FAILURE;
 749     default:
 750         return -1;
 751     }
 752 }