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 tmp1[EVP_MAX_KEY_LENGTH];
  89     unsigned char tmp2[EVP_MAX_KEY_LENGTH];
  90     unsigned char iv1[EVP_MAX_IV_LENGTH * 2];
  91     unsigned char iv2[EVP_MAX_IV_LENGTH * 2];
  92     unsigned char *ms, *key, *iv;
  93     EVP_CIPHER_CTX *dd;
  94     const EVP_CIPHER *c;
  95 #ifndef OPENSSL_NO_COMP
  96     const SSL_COMP *comp;
  97 #endif
  98     const EVP_MD *m;
  99     int mac_type;
 100     size_t *mac_secret_size;
 101     EVP_MD_CTX *mac_ctx;
 102     EVP_PKEY *mac_key;
 103     size_t n, i, j, k, cl;
 104     int reuse_dd = 0;
 105 #ifndef OPENSSL_NO_KTLS
 106     struct tls12_crypto_info_aes_gcm_128 crypto_info;
 107     BIO *wbio;
 108     unsigned char geniv[12];
 109 #endif
 110
 111     c = s->s3->tmp.new_sym_enc;
 112     m = s->s3->tmp.new_hash;
 113     mac_type = s->s3->tmp.new_mac_pkey_type;
 114 #ifndef OPENSSL_NO_COMP
 115     comp = s->s3->tmp.new_compression;
 116 #endif
 117
 118     if (which & SSL3_CC_READ) {
 119         if (s->ext.use_etm)
 120             s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC_READ;
 121         else
 122             s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC_READ;
 123
 124         if (s->s3->tmp.new_cipher->algorithm2 & TLS1_STREAM_MAC)
 125             s->mac_flags |= SSL_MAC_FLAG_READ_MAC_STREAM;
 126         else
 127             s->mac_flags &= ~SSL_MAC_FLAG_READ_MAC_STREAM;
 128
 129         if (s->enc_read_ctx != NULL) {
 130             reuse_dd = 1;
 131         } else if ((s->enc_read_ctx = EVP_CIPHER_CTX_new()) == NULL) {
 132             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 133                      ERR_R_MALLOC_FAILURE);
 134             goto err;
 135         } else {
 136             /*
 137              * make sure it's initialised in case we exit later with an error
 138              */
 139             EVP_CIPHER_CTX_reset(s->enc_read_ctx);
 140         }
 141         dd = s->enc_read_ctx;
 142         mac_ctx = ssl_replace_hash(&s->read_hash, NULL);
 143         if (mac_ctx == NULL) {
 144             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 145                      ERR_R_INTERNAL_ERROR);
 146             goto err;
 147         }
 148 #ifndef OPENSSL_NO_COMP
 149         COMP_CTX_free(s->expand);
 150         s->expand = NULL;
 151         if (comp != NULL) {
 152             s->expand = COMP_CTX_new(comp->method);
 153             if (s->expand == NULL) {
 154                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 155                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 156                          SSL_R_COMPRESSION_LIBRARY_ERROR);
 157                 goto err;
 158             }
 159         }
 160 #endif
 161         /*
 162          * this is done by dtls1_reset_seq_numbers for DTLS
 163          */
 164         if (!SSL_IS_DTLS(s))
 165             RECORD_LAYER_reset_read_sequence(&s->rlayer);
 166         mac_secret = &(s->s3->read_mac_secret[0]);
 167         mac_secret_size = &(s->s3->read_mac_secret_size);
 168     } else {
 169         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
 170         if (s->ext.use_etm)
 171             s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC_WRITE;
 172         else
 173             s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC_WRITE;
 174
 175         if (s->s3->tmp.new_cipher->algorithm2 & TLS1_STREAM_MAC)
 176             s->mac_flags |= SSL_MAC_FLAG_WRITE_MAC_STREAM;
 177         else
 178             s->mac_flags &= ~SSL_MAC_FLAG_WRITE_MAC_STREAM;
 179         if (s->enc_write_ctx != NULL && !SSL_IS_DTLS(s)) {
 180             reuse_dd = 1;
 181         } else if ((s->enc_write_ctx = EVP_CIPHER_CTX_new()) == NULL) {
 182             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 183                      ERR_R_MALLOC_FAILURE);
 184             goto err;
 185         }
 186         dd = s->enc_write_ctx;
 187         if (SSL_IS_DTLS(s)) {
 188             mac_ctx = EVP_MD_CTX_new();
 189             if (mac_ctx == NULL) {
 190                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 191                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 192                          ERR_R_MALLOC_FAILURE);
 193                 goto err;
 194             }
 195             s->write_hash = mac_ctx;
 196         } else {
 197             mac_ctx = ssl_replace_hash(&s->write_hash, NULL);
 198             if (mac_ctx == NULL) {
 199                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 200                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 201                          ERR_R_MALLOC_FAILURE);
 202                 goto err;
 203             }
 204         }
 205 #ifndef OPENSSL_NO_COMP
 206         COMP_CTX_free(s->compress);
 207         s->compress = NULL;
 208         if (comp != NULL) {
 209             s->compress = COMP_CTX_new(comp->method);
 210             if (s->compress == NULL) {
 211                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 212                          SSL_F_TLS1_CHANGE_CIPHER_STATE,
 213                         SSL_R_COMPRESSION_LIBRARY_ERROR);
 214                 goto err;
 215             }
 216         }
 217 #endif
 218         /*
 219          * this is done by dtls1_reset_seq_numbers for DTLS
 220          */
 221         if (!SSL_IS_DTLS(s))
 222             RECORD_LAYER_reset_write_sequence(&s->rlayer);
 223         mac_secret = &(s->s3->write_mac_secret[0]);
 224         mac_secret_size = &(s->s3->write_mac_secret_size);
 225     }
 226
 227     if (reuse_dd)
 228         EVP_CIPHER_CTX_reset(dd);
 229
 230     p = s->s3->tmp.key_block;
 231     i = *mac_secret_size = s->s3->tmp.new_mac_secret_size;
 232
 233     /* TODO(size_t): convert me */
 234     cl = EVP_CIPHER_key_length(c);
 235     j = cl;
 236     /* Was j=(exp)?5:EVP_CIPHER_key_length(c); */
 237     /* If GCM/CCM mode only part of IV comes from PRF */
 238     if (EVP_CIPHER_mode(c) == EVP_CIPH_GCM_MODE)
 239         k = EVP_GCM_TLS_FIXED_IV_LEN;
 240     else if (EVP_CIPHER_mode(c) == EVP_CIPH_CCM_MODE)
 241         k = EVP_CCM_TLS_FIXED_IV_LEN;
 242     else
 243         k = EVP_CIPHER_iv_length(c);
 244     if ((which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
 245         (which == SSL3_CHANGE_CIPHER_SERVER_READ)) {
 246         ms = &(p[0]);
 247         n = i + i;
 248         key = &(p[n]);
 249         n += j + j;
 250         iv = &(p[n]);
 251         n += k + k;
 252     } else {
 253         n = i;
 254         ms = &(p[n]);
 255         n += i + j;
 256         key = &(p[n]);
 257         n += j + k;
 258         iv = &(p[n]);
 259         n += k;
 260     }
 261
 262     if (n > s->s3->tmp.key_block_length) {
 263         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 264                  ERR_R_INTERNAL_ERROR);
 265         goto err;
 266     }
 267
 268     memcpy(mac_secret, ms, i);
 269
 270     if (!(EVP_CIPHER_flags(c) & EVP_CIPH_FLAG_AEAD_CIPHER)) {
 271         /* TODO(size_t): Convert this function */
 272         mac_key = EVP_PKEY_new_mac_key(mac_type, NULL, mac_secret,
 273                                                (int)*mac_secret_size);
 274         if (mac_key == NULL
 275             || EVP_DigestSignInit(mac_ctx, NULL, m, NULL, mac_key) <= 0) {
 276             EVP_PKEY_free(mac_key);
 277             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 278                      ERR_R_INTERNAL_ERROR);
 279             goto err;
 280         }
 281         EVP_PKEY_free(mac_key);
 282     }
 283 #ifdef SSL_DEBUG
 284     printf("which = %04X\nmac key=", which);
 285     {
 286         size_t z;
 287         for (z = 0; z < i; z++)
 288             printf("%02X%c", ms[z], ((z + 1) % 16) ? ' ' : '\n');
 289     }
 290 #endif
 291
 292     if (EVP_CIPHER_mode(c) == EVP_CIPH_GCM_MODE) {
 293         if (!EVP_CipherInit_ex(dd, c, NULL, key, NULL, (which & SSL3_CC_WRITE))
 294             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_GCM_SET_IV_FIXED, (int)k,
 295                                     iv)) {
 296             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 297                      ERR_R_INTERNAL_ERROR);
 298             goto err;
 299         }
 300     } else if (EVP_CIPHER_mode(c) == EVP_CIPH_CCM_MODE) {
 301         int taglen;
 302         if (s->s3->tmp.
 303             new_cipher->algorithm_enc & (SSL_AES128CCM8 | SSL_AES256CCM8))
 304             taglen = EVP_CCM8_TLS_TAG_LEN;
 305         else
 306             taglen = EVP_CCM_TLS_TAG_LEN;
 307         if (!EVP_CipherInit_ex(dd, c, NULL, NULL, NULL, (which & SSL3_CC_WRITE))
 308             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_AEAD_SET_IVLEN, 12, NULL)
 309             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_AEAD_SET_TAG, taglen, NULL)
 310             || !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_CCM_SET_IV_FIXED, (int)k, iv)
 311             || !EVP_CipherInit_ex(dd, NULL, NULL, key, NULL, -1)) {
 312             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 313                      ERR_R_INTERNAL_ERROR);
 314             goto err;
 315         }
 316     } else {
 317         if (!EVP_CipherInit_ex(dd, c, NULL, key, iv, (which & SSL3_CC_WRITE))) {
 318             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 319                      ERR_R_INTERNAL_ERROR);
 320             goto err;
 321         }
 322     }
 323     /* Needed for "composite" AEADs, such as RC4-HMAC-MD5 */
 324     if ((EVP_CIPHER_flags(c) & EVP_CIPH_FLAG_AEAD_CIPHER) && *mac_secret_size
 325         && !EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_AEAD_SET_MAC_KEY,
 326                                 (int)*mac_secret_size, mac_secret)) {
 327         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 328                  ERR_R_INTERNAL_ERROR);
 329         goto err;
 330     }
 331 #ifndef OPENSSL_NO_KTLS
 332     if (s->compress)
 333         goto skip_ktls;
 334
 335     if ((which & SSL3_CC_READ) ||
 336         ((which & SSL3_CC_WRITE) && (s->mode & SSL_MODE_NO_KTLS_TX)))
 337         goto skip_ktls;
 338
 339     /* ktls supports only the maximum fragment size */
 340     if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
 341         goto skip_ktls;
 342
 343     /* check that cipher is AES_GCM_128 */
 344     if (EVP_CIPHER_nid(c) != NID_aes_128_gcm
 345         || EVP_CIPHER_mode(c) != EVP_CIPH_GCM_MODE
 346         || EVP_CIPHER_key_length(c) != TLS_CIPHER_AES_GCM_128_KEY_SIZE)
 347         goto skip_ktls;
 348
 349     /* check version is 1.2 */
 350     if (s->version != TLS1_2_VERSION)
 351         goto skip_ktls;
 352
 353     wbio = s->wbio;
 354     if (!ossl_assert(wbio != NULL)) {
 355         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 356                  ERR_R_INTERNAL_ERROR);
 357         goto err;
 358     }
 359
 360     /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
 361     if (BIO_flush(wbio) <= 0)
 362         goto skip_ktls;
 363
 364     /* ktls doesn't support renegotiation */
 365     if (BIO_get_ktls_send(s->wbio)) {
 366         SSLfatal(s, SSL_AD_NO_RENEGOTIATION, SSL_F_TLS1_CHANGE_CIPHER_STATE,
 367                  ERR_R_INTERNAL_ERROR);
 368         goto err;
 369     }
 370
 371     memset(&crypto_info, 0, sizeof(crypto_info));
 372     crypto_info.info.cipher_type = TLS_CIPHER_AES_GCM_128;
 373     crypto_info.info.version = s->version;
 374
 375     EVP_CIPHER_CTX_ctrl(dd, EVP_CTRL_GET_IV,
 376                         EVP_GCM_TLS_FIXED_IV_LEN + EVP_GCM_TLS_EXPLICIT_IV_LEN,
 377                         geniv);
 378     memcpy(crypto_info.iv, geniv + EVP_GCM_TLS_FIXED_IV_LEN,
 379            TLS_CIPHER_AES_GCM_128_IV_SIZE);
 380     memcpy(crypto_info.salt, geniv, TLS_CIPHER_AES_GCM_128_SALT_SIZE);
 381     memcpy(crypto_info.key, key, EVP_CIPHER_key_length(c));
 382     memcpy(crypto_info.rec_seq, &s->rlayer.write_sequence,
 383            TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
 384
 385     /* ktls works with user provided buffers directly */
 386     if (BIO_set_ktls(wbio, &crypto_info, which & SSL3_CC_WRITE)) {
 387         ssl3_release_write_buffer(s);
 388         SSL_set_options(s, SSL_OP_NO_RENEGOTIATION);
 389     }
 390
 391  skip_ktls:
 392 #endif                          /* OPENSSL_NO_KTLS */
 393     s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
 394
 395 #ifdef SSL_DEBUG
 396     printf("which = %04X\nkey=", which);
 397     {
 398         int z;
 399         for (z = 0; z < EVP_CIPHER_key_length(c); z++)
 400             printf("%02X%c", key[z], ((z + 1) % 16) ? ' ' : '\n');
 401     }
 402     printf("\niv=");
 403     {
 404         size_t z;
 405         for (z = 0; z < k; z++)
 406             printf("%02X%c", iv[z], ((z + 1) % 16) ? ' ' : '\n');
 407     }
 408     printf("\n");
 409 #endif
 410
 411     OPENSSL_cleanse(tmp1, sizeof(tmp1));
 412     OPENSSL_cleanse(tmp2, sizeof(tmp1));
 413     OPENSSL_cleanse(iv1, sizeof(iv1));
 414     OPENSSL_cleanse(iv2, sizeof(iv2));
 415     return 1;
 416  err:
 417     OPENSSL_cleanse(tmp1, sizeof(tmp1));
 418     OPENSSL_cleanse(tmp2, sizeof(tmp1));
 419     OPENSSL_cleanse(iv1, sizeof(iv1));
 420     OPENSSL_cleanse(iv2, sizeof(iv2));
 421     return 0;
 422 }
 423
 424 int tls1_setup_key_block(SSL *s)
 425 {
 426     unsigned char *p;
 427     const EVP_CIPHER *c;
 428     const EVP_MD *hash;
 429     SSL_COMP *comp;
 430     int mac_type = NID_undef;
 431     size_t num, mac_secret_size = 0;
 432     int ret = 0;
 433
 434     if (s->s3->tmp.key_block_length != 0)
 435         return 1;
 436
 437     if (!ssl_cipher_get_evp(s->session, &c, &hash, &mac_type, &mac_secret_size,
 438                             &comp, s->ext.use_etm)) {
 439         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_SETUP_KEY_BLOCK,
 440                  SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
 441         return 0;
 442     }
 443
 444     s->s3->tmp.new_sym_enc = c;
 445     s->s3->tmp.new_hash = hash;
 446     s->s3->tmp.new_mac_pkey_type = mac_type;
 447     s->s3->tmp.new_mac_secret_size = mac_secret_size;
 448     num = EVP_CIPHER_key_length(c) + mac_secret_size + EVP_CIPHER_iv_length(c);
 449     num *= 2;
 450
 451     ssl3_cleanup_key_block(s);
 452
 453     if ((p = OPENSSL_malloc(num)) == NULL) {
 454         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS1_SETUP_KEY_BLOCK,
 455                  ERR_R_MALLOC_FAILURE);
 456         goto err;
 457     }
 458
 459     s->s3->tmp.key_block_length = num;
 460     s->s3->tmp.key_block = p;
 461
 462 #ifdef SSL_DEBUG
 463     printf("client random\n");
 464     {
 465         int z;
 466         for (z = 0; z < SSL3_RANDOM_SIZE; z++)
 467             printf("%02X%c", s->s3->client_random[z],
 468                    ((z + 1) % 16) ? ' ' : '\n');
 469     }
 470     printf("server random\n");
 471     {
 472         int z;
 473         for (z = 0; z < SSL3_RANDOM_SIZE; z++)
 474             printf("%02X%c", s->s3->server_random[z],
 475                    ((z + 1) % 16) ? ' ' : '\n');
 476     }
 477     printf("master key\n");
 478     {
 479         size_t z;
 480         for (z = 0; z < s->session->master_key_length; z++)
 481             printf("%02X%c", s->session->master_key[z],
 482                    ((z + 1) % 16) ? ' ' : '\n');
 483     }
 484 #endif
 485     if (!tls1_generate_key_block(s, p, num)) {
 486         /* SSLfatal() already called */
 487         goto err;
 488     }
 489 #ifdef SSL_DEBUG
 490     printf("\nkey block\n");
 491     {
 492         size_t z;
 493         for (z = 0; z < num; z++)
 494             printf("%02X%c", p[z], ((z + 1) % 16) ? ' ' : '\n');
 495     }
 496 #endif
 497
 498     if (!(s->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS)
 499         && s->method->version <= TLS1_VERSION) {
 500         /*
 501          * enable vulnerability countermeasure for CBC ciphers with known-IV
 502          * problem (http://www.openssl.org/~bodo/tls-cbc.txt)
 503          */
 504         s->s3->need_empty_fragments = 1;
 505
 506         if (s->session->cipher != NULL) {
 507             if (s->session->cipher->algorithm_enc == SSL_eNULL)
 508                 s->s3->need_empty_fragments = 0;
 509
 510 #ifndef OPENSSL_NO_RC4
 511             if (s->session->cipher->algorithm_enc == SSL_RC4)
 512                 s->s3->need_empty_fragments = 0;
 513 #endif
 514         }
 515     }
 516
 517     ret = 1;
 518  err:
 519     return ret;
 520 }
 521
 522 size_t tls1_final_finish_mac(SSL *s, const char *str, size_t slen,
 523                              unsigned char *out)
 524 {
 525     size_t hashlen;
 526     unsigned char hash[EVP_MAX_MD_SIZE];
 527
 528     if (!ssl3_digest_cached_records(s, 0)) {
 529         /* SSLfatal() already called */
 530         return 0;
 531     }
 532
 533     if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
 534         /* SSLfatal() already called */
 535         return 0;
 536     }
 537
 538     if (!tls1_PRF(s, str, slen, hash, hashlen, NULL, 0, NULL, 0, NULL, 0,
 539                   s->session->master_key, s->session->master_key_length,
 540                   out, TLS1_FINISH_MAC_LENGTH, 1)) {
 541         /* SSLfatal() already called */
 542         return 0;
 543     }
 544     OPENSSL_cleanse(hash, hashlen);
 545     return TLS1_FINISH_MAC_LENGTH;
 546 }
 547
 548 int tls1_generate_master_secret(SSL *s, unsigned char *out, unsigned char *p,
 549                                 size_t len, size_t *secret_size)
 550 {
 551     if (s->session->flags & SSL_SESS_FLAG_EXTMS) {
 552         unsigned char hash[EVP_MAX_MD_SIZE * 2];
 553         size_t hashlen;
 554         /*
 555          * Digest cached records keeping record buffer (if present): this wont
 556          * affect client auth because we're freezing the buffer at the same
 557          * point (after client key exchange and before certificate verify)
 558          */
 559         if (!ssl3_digest_cached_records(s, 1)
 560                 || !ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
 561             /* SSLfatal() already called */
 562             return 0;
 563         }
 564 #ifdef SSL_DEBUG
 565         fprintf(stderr, "Handshake hashes:\n");
 566         BIO_dump_fp(stderr, (char *)hash, hashlen);
 567 #endif
 568         if (!tls1_PRF(s,
 569                       TLS_MD_EXTENDED_MASTER_SECRET_CONST,
 570                       TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE,
 571                       hash, hashlen,
 572                       NULL, 0,
 573                       NULL, 0,
 574                       NULL, 0, p, len, out,
 575                       SSL3_MASTER_SECRET_SIZE, 1)) {
 576             /* SSLfatal() already called */
 577             return 0;
 578         }
 579         OPENSSL_cleanse(hash, hashlen);
 580     } else {
 581         if (!tls1_PRF(s,
 582                       TLS_MD_MASTER_SECRET_CONST,
 583                       TLS_MD_MASTER_SECRET_CONST_SIZE,
 584                       s->s3->client_random, SSL3_RANDOM_SIZE,
 585                       NULL, 0,
 586                       s->s3->server_random, SSL3_RANDOM_SIZE,
 587                       NULL, 0, p, len, out,
 588                       SSL3_MASTER_SECRET_SIZE, 1)) {
 589            /* SSLfatal() already called */
 590             return 0;
 591         }
 592     }
 593 #ifdef SSL_DEBUG
 594     fprintf(stderr, "Premaster Secret:\n");
 595     BIO_dump_fp(stderr, (char *)p, len);
 596     fprintf(stderr, "Client Random:\n");
 597     BIO_dump_fp(stderr, (char *)s->s3->client_random, SSL3_RANDOM_SIZE);
 598     fprintf(stderr, "Server Random:\n");
 599     BIO_dump_fp(stderr, (char *)s->s3->server_random, SSL3_RANDOM_SIZE);
 600     fprintf(stderr, "Master Secret:\n");
 601     BIO_dump_fp(stderr, (char *)s->session->master_key,
 602                 SSL3_MASTER_SECRET_SIZE);
 603 #endif
 604
 605     *secret_size = SSL3_MASTER_SECRET_SIZE;
 606     return 1;
 607 }
 608
 609 int tls1_export_keying_material(SSL *s, unsigned char *out, size_t olen,
 610                                 const char *label, size_t llen,
 611                                 const unsigned char *context,
 612                                 size_t contextlen, int use_context)
 613 {
 614     unsigned char *val = NULL;
 615     size_t vallen = 0, currentvalpos;
 616     int rv;
 617
 618     /*
 619      * construct PRF arguments we construct the PRF argument ourself rather
 620      * than passing separate values into the TLS PRF to ensure that the
 621      * concatenation of values does not create a prohibited label.
 622      */
 623     vallen = llen + SSL3_RANDOM_SIZE * 2;
 624     if (use_context) {
 625         vallen += 2 + contextlen;
 626     }
 627
 628     val = OPENSSL_malloc(vallen);
 629     if (val == NULL)
 630         goto err2;
 631     currentvalpos = 0;
 632     memcpy(val + currentvalpos, (unsigned char *)label, llen);
 633     currentvalpos += llen;
 634     memcpy(val + currentvalpos, s->s3->client_random, SSL3_RANDOM_SIZE);
 635     currentvalpos += SSL3_RANDOM_SIZE;
 636     memcpy(val + currentvalpos, s->s3->server_random, SSL3_RANDOM_SIZE);
 637     currentvalpos += SSL3_RANDOM_SIZE;
 638
 639     if (use_context) {
 640         val[currentvalpos] = (contextlen >> 8) & 0xff;
 641         currentvalpos++;
 642         val[currentvalpos] = contextlen & 0xff;
 643         currentvalpos++;
 644         if ((contextlen > 0) || (context != NULL)) {
 645             memcpy(val + currentvalpos, context, contextlen);
 646         }
 647     }
 648
 649     /*
 650      * disallow prohibited labels note that SSL3_RANDOM_SIZE > max(prohibited
 651      * label len) = 15, so size of val > max(prohibited label len) = 15 and
 652      * the comparisons won't have buffer overflow
 653      */
 654     if (memcmp(val, TLS_MD_CLIENT_FINISH_CONST,
 655                TLS_MD_CLIENT_FINISH_CONST_SIZE) == 0)
 656         goto err1;
 657     if (memcmp(val, TLS_MD_SERVER_FINISH_CONST,
 658                TLS_MD_SERVER_FINISH_CONST_SIZE) == 0)
 659         goto err1;
 660     if (memcmp(val, TLS_MD_MASTER_SECRET_CONST,
 661                TLS_MD_MASTER_SECRET_CONST_SIZE) == 0)
 662         goto err1;
 663     if (memcmp(val, TLS_MD_EXTENDED_MASTER_SECRET_CONST,
 664                TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE) == 0)
 665         goto err1;
 666     if (memcmp(val, TLS_MD_KEY_EXPANSION_CONST,
 667                TLS_MD_KEY_EXPANSION_CONST_SIZE) == 0)
 668         goto err1;
 669
 670     rv = tls1_PRF(s,
 671                   val, vallen,
 672                   NULL, 0,
 673                   NULL, 0,
 674                   NULL, 0,
 675                   NULL, 0,
 676                   s->session->master_key, s->session->master_key_length,
 677                   out, olen, 0);
 678
 679     goto ret;
 680  err1:
 681     SSLerr(SSL_F_TLS1_EXPORT_KEYING_MATERIAL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
 682     rv = 0;
 683     goto ret;
 684  err2:
 685     SSLerr(SSL_F_TLS1_EXPORT_KEYING_MATERIAL, ERR_R_MALLOC_FAILURE);
 686     rv = 0;
 687  ret:
 688     OPENSSL_clear_free(val, vallen);
 689     return rv;
 690 }
 691
 692 int tls1_alert_code(int code)
 693 {
 694     switch (code) {
 695     case SSL_AD_CLOSE_NOTIFY:
 696         return SSL3_AD_CLOSE_NOTIFY;
 697     case SSL_AD_UNEXPECTED_MESSAGE:
 698         return SSL3_AD_UNEXPECTED_MESSAGE;
 699     case SSL_AD_BAD_RECORD_MAC:
 700         return SSL3_AD_BAD_RECORD_MAC;
 701     case SSL_AD_DECRYPTION_FAILED:
 702         return TLS1_AD_DECRYPTION_FAILED;
 703     case SSL_AD_RECORD_OVERFLOW:
 704         return TLS1_AD_RECORD_OVERFLOW;
 705     case SSL_AD_DECOMPRESSION_FAILURE:
 706         return SSL3_AD_DECOMPRESSION_FAILURE;
 707     case SSL_AD_HANDSHAKE_FAILURE:
 708         return SSL3_AD_HANDSHAKE_FAILURE;
 709     case SSL_AD_NO_CERTIFICATE:
 710         return -1;
 711     case SSL_AD_BAD_CERTIFICATE:
 712         return SSL3_AD_BAD_CERTIFICATE;
 713     case SSL_AD_UNSUPPORTED_CERTIFICATE:
 714         return SSL3_AD_UNSUPPORTED_CERTIFICATE;
 715     case SSL_AD_CERTIFICATE_REVOKED:
 716         return SSL3_AD_CERTIFICATE_REVOKED;
 717     case SSL_AD_CERTIFICATE_EXPIRED:
 718         return SSL3_AD_CERTIFICATE_EXPIRED;
 719     case SSL_AD_CERTIFICATE_UNKNOWN:
 720         return SSL3_AD_CERTIFICATE_UNKNOWN;
 721     case SSL_AD_ILLEGAL_PARAMETER:
 722         return SSL3_AD_ILLEGAL_PARAMETER;
 723     case SSL_AD_UNKNOWN_CA:
 724         return TLS1_AD_UNKNOWN_CA;
 725     case SSL_AD_ACCESS_DENIED:
 726         return TLS1_AD_ACCESS_DENIED;
 727     case SSL_AD_DECODE_ERROR:
 728         return TLS1_AD_DECODE_ERROR;
 729     case SSL_AD_DECRYPT_ERROR:
 730         return TLS1_AD_DECRYPT_ERROR;
 731     case SSL_AD_EXPORT_RESTRICTION:
 732         return TLS1_AD_EXPORT_RESTRICTION;
 733     case SSL_AD_PROTOCOL_VERSION:
 734         return TLS1_AD_PROTOCOL_VERSION;
 735     case SSL_AD_INSUFFICIENT_SECURITY:
 736         return TLS1_AD_INSUFFICIENT_SECURITY;
 737     case SSL_AD_INTERNAL_ERROR:
 738         return TLS1_AD_INTERNAL_ERROR;
 739     case SSL_AD_USER_CANCELLED:
 740         return TLS1_AD_USER_CANCELLED;
 741     case SSL_AD_NO_RENEGOTIATION:
 742         return TLS1_AD_NO_RENEGOTIATION;
 743     case SSL_AD_UNSUPPORTED_EXTENSION:
 744         return TLS1_AD_UNSUPPORTED_EXTENSION;
 745     case SSL_AD_CERTIFICATE_UNOBTAINABLE:
 746         return TLS1_AD_CERTIFICATE_UNOBTAINABLE;
 747     case SSL_AD_UNRECOGNIZED_NAME:
 748         return TLS1_AD_UNRECOGNIZED_NAME;
 749     case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
 750         return TLS1_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
 751     case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
 752         return TLS1_AD_BAD_CERTIFICATE_HASH_VALUE;
 753     case SSL_AD_UNKNOWN_PSK_IDENTITY:
 754         return TLS1_AD_UNKNOWN_PSK_IDENTITY;
 755     case SSL_AD_INAPPROPRIATE_FALLBACK:
 756         return TLS1_AD_INAPPROPRIATE_FALLBACK;
 757     case SSL_AD_NO_APPLICATION_PROTOCOL:
 758         return TLS1_AD_NO_APPLICATION_PROTOCOL;
 759     case SSL_AD_CERTIFICATE_REQUIRED:
 760         return SSL_AD_HANDSHAKE_FAILURE;
 761     default:
 762         return -1;
 763     }
 764 }