ssl/s3_enc.c

   1 /*
   2  * Copyright 1995-2021 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_local.h"
  13 #include <openssl/evp.h>
  14 #include <openssl/md5.h>
  15 #include <openssl/core_names.h>
  16 #include "internal/cryptlib.h"
  17
  18 static int ssl3_generate_key_block(SSL_CONNECTION *s, unsigned char *km, int num)
  19 {
  20     const EVP_MD *md5 = NULL, *sha1 = NULL;
  21     EVP_MD_CTX *m5;
  22     EVP_MD_CTX *s1;
  23     unsigned char buf[16], smd[SHA_DIGEST_LENGTH];
  24     unsigned char c = 'A';
  25     unsigned int i, k;
  26     int ret = 0;
  27     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
  28
  29 #ifdef CHARSET_EBCDIC
  30     c = os_toascii[c];          /* 'A' in ASCII */
  31 #endif
  32     k = 0;
  33     md5 = ssl_evp_md_fetch(sctx->libctx, NID_md5, sctx->propq);
  34     sha1 = ssl_evp_md_fetch(sctx->libctx, NID_sha1, sctx->propq);
  35     m5 = EVP_MD_CTX_new();
  36     s1 = EVP_MD_CTX_new();
  37     if (md5 == NULL || sha1 == NULL || m5 == NULL || s1 == NULL) {
  38         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
  39         goto err;
  40     }
  41     for (i = 0; (int)i < num; i += MD5_DIGEST_LENGTH) {
  42         k++;
  43         if (k > sizeof(buf)) {
  44             /* bug: 'buf' is too small for this ciphersuite */
  45             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
  46             goto err;
  47         }
  48
  49         memset(buf, c, k);
  50         c++;
  51         if (!EVP_DigestInit_ex(s1, sha1, NULL)
  52             || !EVP_DigestUpdate(s1, buf, k)
  53             || !EVP_DigestUpdate(s1, s->session->master_key,
  54                                  s->session->master_key_length)
  55             || !EVP_DigestUpdate(s1, s->s3.server_random, SSL3_RANDOM_SIZE)
  56             || !EVP_DigestUpdate(s1, s->s3.client_random, SSL3_RANDOM_SIZE)
  57             || !EVP_DigestFinal_ex(s1, smd, NULL)
  58             || !EVP_DigestInit_ex(m5, md5, NULL)
  59             || !EVP_DigestUpdate(m5, s->session->master_key,
  60                                  s->session->master_key_length)
  61             || !EVP_DigestUpdate(m5, smd, SHA_DIGEST_LENGTH)) {
  62             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
  63             goto err;
  64         }
  65         if ((int)(i + MD5_DIGEST_LENGTH) > num) {
  66             if (!EVP_DigestFinal_ex(m5, smd, NULL)) {
  67                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
  68                 goto err;
  69             }
  70             memcpy(km, smd, (num - i));
  71         } else {
  72             if (!EVP_DigestFinal_ex(m5, km, NULL)) {
  73                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
  74                 goto err;
  75             }
  76         }
  77
  78         km += MD5_DIGEST_LENGTH;
  79     }
  80     OPENSSL_cleanse(smd, sizeof(smd));
  81     ret = 1;
  82  err:
  83     EVP_MD_CTX_free(m5);
  84     EVP_MD_CTX_free(s1);
  85     ssl_evp_md_free(md5);
  86     ssl_evp_md_free(sha1);
  87     return ret;
  88 }
  89
  90 int ssl3_change_cipher_state(SSL_CONNECTION *s, int which)
  91 {
  92     unsigned char *p, *mac_secret;
  93     size_t md_len;
  94     unsigned char *key, *iv;
  95     const EVP_CIPHER *ciph;
  96     const SSL_COMP *comp = NULL;
  97     const EVP_MD *md;
  98     int mdi;
  99     size_t n, iv_len, key_len;
 100     int direction = (which & SSL3_CC_READ) != 0 ? OSSL_RECORD_DIRECTION_READ
 101                                                 : OSSL_RECORD_DIRECTION_WRITE;
 102
 103     ciph = s->s3.tmp.new_sym_enc;
 104     md = s->s3.tmp.new_hash;
 105     /* m == NULL will lead to a crash later */
 106     if (!ossl_assert(md != NULL)) {
 107         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 108         goto err;
 109     }
 110 #ifndef OPENSSL_NO_COMP
 111     comp = s->s3.tmp.new_compression;
 112 #endif
 113
 114     p = s->s3.tmp.key_block;
 115     mdi = EVP_MD_get_size(md);
 116     if (mdi < 0) {
 117         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 118         goto err;
 119     }
 120     md_len = (size_t)mdi;
 121     key_len = EVP_CIPHER_get_key_length(ciph);
 122     iv_len = EVP_CIPHER_get_iv_length(ciph);
 123     if ((which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
 124         (which == SSL3_CHANGE_CIPHER_SERVER_READ)) {
 125         mac_secret = &(p[0]);
 126         n = md_len + md_len;
 127         key = &(p[n]);
 128         n += key_len + key_len;
 129         iv = &(p[n]);
 130         n += iv_len + iv_len;
 131     } else {
 132         n = md_len;
 133         mac_secret = &(p[n]);
 134         n += md_len + key_len;
 135         key = &(p[n]);
 136         n += key_len + iv_len;
 137         iv = &(p[n]);
 138         n += iv_len;
 139     }
 140
 141     if (n > s->s3.tmp.key_block_length) {
 142         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 143         goto err;
 144     }
 145
 146     if ((which & SSL3_CC_WRITE) != 0)
 147         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
 148
 149     if (!ssl_set_new_record_layer(s, SSL3_VERSION,
 150                                   direction,
 151                                   OSSL_RECORD_PROTECTION_LEVEL_APPLICATION,
 152                                   key, key_len, iv, iv_len, mac_secret,
 153                                   md_len, ciph, 0, NID_undef, md, comp)) {
 154         /* SSLfatal already called */
 155         goto err;
 156     }
 157
 158     s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
 159     return 1;
 160  err:
 161     return 0;
 162 }
 163
 164 int ssl3_setup_key_block(SSL_CONNECTION *s)
 165 {
 166     unsigned char *p;
 167     const EVP_CIPHER *c;
 168     const EVP_MD *hash;
 169     int num;
 170     int ret = 0;
 171     SSL_COMP *comp;
 172
 173     if (s->s3.tmp.key_block_length != 0)
 174         return 1;
 175
 176     if (!ssl_cipher_get_evp(SSL_CONNECTION_GET_CTX(s), s->session, &c, &hash,
 177                             NULL, NULL, &comp, 0)) {
 178         /* Error is already recorded */
 179         SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
 180         return 0;
 181     }
 182
 183     ssl_evp_cipher_free(s->s3.tmp.new_sym_enc);
 184     s->s3.tmp.new_sym_enc = c;
 185     ssl_evp_md_free(s->s3.tmp.new_hash);
 186     s->s3.tmp.new_hash = hash;
 187 #ifdef OPENSSL_NO_COMP
 188     s->s3.tmp.new_compression = NULL;
 189 #else
 190     s->s3.tmp.new_compression = comp;
 191 #endif
 192
 193     num = EVP_MD_get_size(hash);
 194     if (num < 0)
 195         return 0;
 196
 197     num = EVP_CIPHER_get_key_length(c) + num + EVP_CIPHER_get_iv_length(c);
 198     num *= 2;
 199
 200     ssl3_cleanup_key_block(s);
 201
 202     if ((p = OPENSSL_malloc(num)) == NULL) {
 203         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
 204         return 0;
 205     }
 206
 207     s->s3.tmp.key_block_length = num;
 208     s->s3.tmp.key_block = p;
 209
 210     /* Calls SSLfatal() as required */
 211     ret = ssl3_generate_key_block(s, p, num);
 212
 213     return ret;
 214 }
 215
 216 void ssl3_cleanup_key_block(SSL_CONNECTION *s)
 217 {
 218     OPENSSL_clear_free(s->s3.tmp.key_block, s->s3.tmp.key_block_length);
 219     s->s3.tmp.key_block = NULL;
 220     s->s3.tmp.key_block_length = 0;
 221 }
 222
 223 int ssl3_init_finished_mac(SSL_CONNECTION *s)
 224 {
 225     BIO *buf = BIO_new(BIO_s_mem());
 226
 227     if (buf == NULL) {
 228         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BIO_LIB);
 229         return 0;
 230     }
 231     ssl3_free_digest_list(s);
 232     s->s3.handshake_buffer = buf;
 233     (void)BIO_set_close(s->s3.handshake_buffer, BIO_CLOSE);
 234     return 1;
 235 }
 236
 237 /*
 238  * Free digest list. Also frees handshake buffer since they are always freed
 239  * together.
 240  */
 241
 242 void ssl3_free_digest_list(SSL_CONNECTION *s)
 243 {
 244     BIO_free(s->s3.handshake_buffer);
 245     s->s3.handshake_buffer = NULL;
 246     EVP_MD_CTX_free(s->s3.handshake_dgst);
 247     s->s3.handshake_dgst = NULL;
 248 }
 249
 250 int ssl3_finish_mac(SSL_CONNECTION *s, const unsigned char *buf, size_t len)
 251 {
 252     int ret;
 253
 254     if (s->s3.handshake_dgst == NULL) {
 255         /* Note: this writes to a memory BIO so a failure is a fatal error */
 256         if (len > INT_MAX) {
 257             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_OVERFLOW_ERROR);
 258             return 0;
 259         }
 260         ret = BIO_write(s->s3.handshake_buffer, (void *)buf, (int)len);
 261         if (ret <= 0 || ret != (int)len) {
 262             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 263             return 0;
 264         }
 265     } else {
 266         ret = EVP_DigestUpdate(s->s3.handshake_dgst, buf, len);
 267         if (!ret) {
 268             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 269             return 0;
 270         }
 271     }
 272     return 1;
 273 }
 274
 275 int ssl3_digest_cached_records(SSL_CONNECTION *s, int keep)
 276 {
 277     const EVP_MD *md;
 278     long hdatalen;
 279     void *hdata;
 280
 281     if (s->s3.handshake_dgst == NULL) {
 282         hdatalen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
 283         if (hdatalen <= 0) {
 284             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);
 285             return 0;
 286         }
 287
 288         s->s3.handshake_dgst = EVP_MD_CTX_new();
 289         if (s->s3.handshake_dgst == NULL) {
 290             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
 291             return 0;
 292         }
 293
 294         md = ssl_handshake_md(s);
 295         if (md == NULL) {
 296             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
 297                      SSL_R_NO_SUITABLE_DIGEST_ALGORITHM);
 298             return 0;
 299         }
 300         if (!EVP_DigestInit_ex(s->s3.handshake_dgst, md, NULL)
 301             || !EVP_DigestUpdate(s->s3.handshake_dgst, hdata, hdatalen)) {
 302             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 303             return 0;
 304         }
 305     }
 306     if (keep == 0) {
 307         BIO_free(s->s3.handshake_buffer);
 308         s->s3.handshake_buffer = NULL;
 309     }
 310
 311     return 1;
 312 }
 313
 314 void ssl3_digest_master_key_set_params(const SSL_SESSION *session,
 315                                        OSSL_PARAM params[])
 316 {
 317     int n = 0;
 318     params[n++] = OSSL_PARAM_construct_octet_string(OSSL_DIGEST_PARAM_SSL3_MS,
 319                                                     (void *)session->master_key,
 320                                                     session->master_key_length);
 321     params[n++] = OSSL_PARAM_construct_end();
 322 }
 323
 324 size_t ssl3_final_finish_mac(SSL_CONNECTION *s, const char *sender, size_t len,
 325                              unsigned char *p)
 326 {
 327     int ret;
 328     EVP_MD_CTX *ctx = NULL;
 329
 330     if (!ssl3_digest_cached_records(s, 0)) {
 331         /* SSLfatal() already called */
 332         return 0;
 333     }
 334
 335     if (EVP_MD_CTX_get_type(s->s3.handshake_dgst) != NID_md5_sha1) {
 336         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_REQUIRED_DIGEST);
 337         return 0;
 338     }
 339
 340     ctx = EVP_MD_CTX_new();
 341     if (ctx == NULL) {
 342         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
 343         return 0;
 344     }
 345     if (!EVP_MD_CTX_copy_ex(ctx, s->s3.handshake_dgst)) {
 346         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 347         ret = 0;
 348         goto err;
 349     }
 350
 351     ret = EVP_MD_CTX_get_size(ctx);
 352     if (ret < 0) {
 353         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 354         ret = 0;
 355         goto err;
 356     }
 357
 358     if (sender != NULL) {
 359         OSSL_PARAM digest_cmd_params[3];
 360
 361         ssl3_digest_master_key_set_params(s->session, digest_cmd_params);
 362
 363         if (EVP_DigestUpdate(ctx, sender, len) <= 0
 364             || EVP_MD_CTX_set_params(ctx, digest_cmd_params) <= 0
 365             || EVP_DigestFinal_ex(ctx, p, NULL) <= 0) {
 366                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 367                 ret = 0;
 368         }
 369     }
 370
 371  err:
 372     EVP_MD_CTX_free(ctx);
 373
 374     return ret;
 375 }
 376
 377 int ssl3_generate_master_secret(SSL_CONNECTION *s, unsigned char *out,
 378                                 unsigned char *p,
 379                                 size_t len, size_t *secret_size)
 380 {
 381     static const unsigned char *salt[3] = {
 382 #ifndef CHARSET_EBCDIC
 383         (const unsigned char *)"A",
 384         (const unsigned char *)"BB",
 385         (const unsigned char *)"CCC",
 386 #else
 387         (const unsigned char *)"\x41",
 388         (const unsigned char *)"\x42\x42",
 389         (const unsigned char *)"\x43\x43\x43",
 390 #endif
 391     };
 392     unsigned char buf[EVP_MAX_MD_SIZE];
 393     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
 394     int i, ret = 1;
 395     unsigned int n;
 396     size_t ret_secret_size = 0;
 397
 398     if (ctx == NULL) {
 399         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
 400         return 0;
 401     }
 402     for (i = 0; i < 3; i++) {
 403         if (EVP_DigestInit_ex(ctx, SSL_CONNECTION_GET_CTX(s)->sha1, NULL) <= 0
 404             || EVP_DigestUpdate(ctx, salt[i],
 405                                 strlen((const char *)salt[i])) <= 0
 406             || EVP_DigestUpdate(ctx, p, len) <= 0
 407             || EVP_DigestUpdate(ctx, &(s->s3.client_random[0]),
 408                                 SSL3_RANDOM_SIZE) <= 0
 409             || EVP_DigestUpdate(ctx, &(s->s3.server_random[0]),
 410                                 SSL3_RANDOM_SIZE) <= 0
 411             || EVP_DigestFinal_ex(ctx, buf, &n) <= 0
 412             || EVP_DigestInit_ex(ctx, SSL_CONNECTION_GET_CTX(s)->md5, NULL) <= 0
 413             || EVP_DigestUpdate(ctx, p, len) <= 0
 414             || EVP_DigestUpdate(ctx, buf, n) <= 0
 415             || EVP_DigestFinal_ex(ctx, out, &n) <= 0) {
 416             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 417             ret = 0;
 418             break;
 419         }
 420         out += n;
 421         ret_secret_size += n;
 422     }
 423     EVP_MD_CTX_free(ctx);
 424
 425     OPENSSL_cleanse(buf, sizeof(buf));
 426     if (ret)
 427         *secret_size = ret_secret_size;
 428     return ret;
 429 }
 430
 431 int ssl3_alert_code(int code)
 432 {
 433     switch (code) {
 434     case SSL_AD_CLOSE_NOTIFY:
 435         return SSL3_AD_CLOSE_NOTIFY;
 436     case SSL_AD_UNEXPECTED_MESSAGE:
 437         return SSL3_AD_UNEXPECTED_MESSAGE;
 438     case SSL_AD_BAD_RECORD_MAC:
 439         return SSL3_AD_BAD_RECORD_MAC;
 440     case SSL_AD_DECRYPTION_FAILED:
 441         return SSL3_AD_BAD_RECORD_MAC;
 442     case SSL_AD_RECORD_OVERFLOW:
 443         return SSL3_AD_BAD_RECORD_MAC;
 444     case SSL_AD_DECOMPRESSION_FAILURE:
 445         return SSL3_AD_DECOMPRESSION_FAILURE;
 446     case SSL_AD_HANDSHAKE_FAILURE:
 447         return SSL3_AD_HANDSHAKE_FAILURE;
 448     case SSL_AD_NO_CERTIFICATE:
 449         return SSL3_AD_NO_CERTIFICATE;
 450     case SSL_AD_BAD_CERTIFICATE:
 451         return SSL3_AD_BAD_CERTIFICATE;
 452     case SSL_AD_UNSUPPORTED_CERTIFICATE:
 453         return SSL3_AD_UNSUPPORTED_CERTIFICATE;
 454     case SSL_AD_CERTIFICATE_REVOKED:
 455         return SSL3_AD_CERTIFICATE_REVOKED;
 456     case SSL_AD_CERTIFICATE_EXPIRED:
 457         return SSL3_AD_CERTIFICATE_EXPIRED;
 458     case SSL_AD_CERTIFICATE_UNKNOWN:
 459         return SSL3_AD_CERTIFICATE_UNKNOWN;
 460     case SSL_AD_ILLEGAL_PARAMETER:
 461         return SSL3_AD_ILLEGAL_PARAMETER;
 462     case SSL_AD_UNKNOWN_CA:
 463         return SSL3_AD_BAD_CERTIFICATE;
 464     case SSL_AD_ACCESS_DENIED:
 465         return SSL3_AD_HANDSHAKE_FAILURE;
 466     case SSL_AD_DECODE_ERROR:
 467         return SSL3_AD_HANDSHAKE_FAILURE;
 468     case SSL_AD_DECRYPT_ERROR:
 469         return SSL3_AD_HANDSHAKE_FAILURE;
 470     case SSL_AD_EXPORT_RESTRICTION:
 471         return SSL3_AD_HANDSHAKE_FAILURE;
 472     case SSL_AD_PROTOCOL_VERSION:
 473         return SSL3_AD_HANDSHAKE_FAILURE;
 474     case SSL_AD_INSUFFICIENT_SECURITY:
 475         return SSL3_AD_HANDSHAKE_FAILURE;
 476     case SSL_AD_INTERNAL_ERROR:
 477         return SSL3_AD_HANDSHAKE_FAILURE;
 478     case SSL_AD_USER_CANCELLED:
 479         return SSL3_AD_HANDSHAKE_FAILURE;
 480     case SSL_AD_NO_RENEGOTIATION:
 481         return -1;            /* Don't send it :-) */
 482     case SSL_AD_UNSUPPORTED_EXTENSION:
 483         return SSL3_AD_HANDSHAKE_FAILURE;
 484     case SSL_AD_CERTIFICATE_UNOBTAINABLE:
 485         return SSL3_AD_HANDSHAKE_FAILURE;
 486     case SSL_AD_UNRECOGNIZED_NAME:
 487         return SSL3_AD_HANDSHAKE_FAILURE;
 488     case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
 489         return SSL3_AD_HANDSHAKE_FAILURE;
 490     case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
 491         return SSL3_AD_HANDSHAKE_FAILURE;
 492     case SSL_AD_UNKNOWN_PSK_IDENTITY:
 493         return TLS1_AD_UNKNOWN_PSK_IDENTITY;
 494     case SSL_AD_INAPPROPRIATE_FALLBACK:
 495         return TLS1_AD_INAPPROPRIATE_FALLBACK;
 496     case SSL_AD_NO_APPLICATION_PROTOCOL:
 497         return TLS1_AD_NO_APPLICATION_PROTOCOL;
 498     case SSL_AD_CERTIFICATE_REQUIRED:
 499         return SSL_AD_HANDSHAKE_FAILURE;
 500     case TLS13_AD_MISSING_EXTENSION:
 501         return SSL_AD_HANDSHAKE_FAILURE;
 502     default:
 503         return -1;
 504     }
 505 }