1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2  * All rights reserved.
3  *
4  * This package is an SSL implementation written
5  * by Eric Young (eay@cryptsoft.com).
6  * The implementation was written so as to conform with Netscapes SSL.
7  *
8  * This library is free for commercial and non-commercial use as long as
9  * the following conditions are aheared to.  The following conditions
10  * apply to all code found in this distribution, be it the RC4, RSA,
11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
12  * included with this distribution is covered by the same copyright terms
13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14  *
15  * Copyright remains Eric Young's, and as such any Copyright notices in
16  * the code are not to be removed.
17  * If this package is used in a product, Eric Young should be given attribution
18  * as the author of the parts of the library used.
19  * This can be in the form of a textual message at program startup or
20  * in documentation (online or textual) provided with the package.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  * 1. Redistributions of source code must retain the copyright
26  *    notice, this list of conditions and the following disclaimer.
27  * 2. Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in the
29  *    documentation and/or other materials provided with the distribution.
30  * 3. All advertising materials mentioning features or use of this software
31  *    must display the following acknowledgement:
32  *    "This product includes cryptographic software written by
33  *     Eric Young (eay@cryptsoft.com)"
34  *    The word 'cryptographic' can be left out if the rouines from the library
35  *    being used are not cryptographic related :-).
36  * 4. If you include any Windows specific code (or a derivative thereof) from
37  *    the apps directory (application code) you must include an acknowledgement:
38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50  * SUCH DAMAGE.
51  *
52  * The licence and distribution terms for any publically available version or
53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
54  * copied and put under another distribution licence
55  * [including the GNU Public Licence.]
56  */
57 /* ====================================================================
58  * Copyright (c) 1998-2007 The OpenSSL Project.  All rights reserved.
59  *
60  * Redistribution and use in source and binary forms, with or without
61  * modification, are permitted provided that the following conditions
62  * are met:
63  *
64  * 1. Redistributions of source code must retain the above copyright
65  *    notice, this list of conditions and the following disclaimer.
66  *
67  * 2. Redistributions in binary form must reproduce the above copyright
68  *    notice, this list of conditions and the following disclaimer in
69  *    the documentation and/or other materials provided with the
70  *    distribution.
71  *
72  * 3. All advertising materials mentioning features or use of this
73  *    software must display the following acknowledgment:
74  *    "This product includes software developed by the OpenSSL Project
75  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
76  *
77  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
78  *    endorse or promote products derived from this software without
79  *    prior written permission. For written permission, please contact
80  *    openssl-core@openssl.org.
81  *
82  * 5. Products derived from this software may not be called "OpenSSL"
83  *    nor may "OpenSSL" appear in their names without prior written
84  *    permission of the OpenSSL Project.
85  *
86  * 6. Redistributions of any form whatsoever must retain the following
87  *    acknowledgment:
88  *    "This product includes software developed by the OpenSSL Project
89  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
90  *
91  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
92  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
94  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
95  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
96  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
97  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
98  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
99  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
100  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
101  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
102  * OF THE POSSIBILITY OF SUCH DAMAGE.
103  * ====================================================================
104  *
105  * This product includes cryptographic software written by Eric Young
106  * (eay@cryptsoft.com).  This product includes software written by Tim
107  * Hudson (tjh@cryptsoft.com).
108  *
109  */
110 /* ====================================================================
111  * Copyright 2005 Nokia. All rights reserved.
112  *
113  * The portions of the attached software ("Contribution") is developed by
114  * Nokia Corporation and is licensed pursuant to the OpenSSL open source
115  * license.
116  *
117  * The Contribution, originally written by Mika Kousa and Pasi Eronen of
118  * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
119  * support (see RFC 4279) to OpenSSL.
120  *
121  * No patent licenses or other rights except those expressly stated in
122  * the OpenSSL open source license shall be deemed granted or received
123  * expressly, by implication, estoppel, or otherwise.
124  *
125  * No assurances are provided by Nokia that the Contribution does not
126  * infringe the patent or other intellectual property rights of any third
127  * party or that the license provides you with all the necessary rights
128  * to make use of the Contribution.
129  *
130  * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
131  * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
132  * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
133  * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
134  * OTHERWISE. */
135 
136 #include <openssl/ssl.h>
137 
138 #include <assert.h>
139 #include <stdio.h>
140 #include <string.h>
141 
142 #include <openssl/err.h>
143 #include <openssl/evp.h>
144 #include <openssl/hmac.h>
145 #include <openssl/md5.h>
146 #include <openssl/mem.h>
147 #include <openssl/obj.h>
148 #include <openssl/rand.h>
149 
150 #include "internal.h"
151 
152 
153 /* tls1_P_hash computes the TLS P_<hash> function as described in RFC 5246,
154  * section 5. It XORs |out_len| bytes to |out|, using |md| as the hash and
155  * |secret| as the secret. |seed1| through |seed3| are concatenated to form the
156  * seed parameter. It returns one on success and zero on failure. */
tls1_P_hash(uint8_t * out,size_t out_len,const EVP_MD * md,const uint8_t * secret,size_t secret_len,const uint8_t * seed1,size_t seed1_len,const uint8_t * seed2,size_t seed2_len,const uint8_t * seed3,size_t seed3_len)157 static int tls1_P_hash(uint8_t *out, size_t out_len, const EVP_MD *md,
158                        const uint8_t *secret, size_t secret_len,
159                        const uint8_t *seed1, size_t seed1_len,
160                        const uint8_t *seed2, size_t seed2_len,
161                        const uint8_t *seed3, size_t seed3_len) {
162   HMAC_CTX ctx, ctx_tmp, ctx_init;
163   uint8_t A1[EVP_MAX_MD_SIZE];
164   unsigned A1_len;
165   int ret = 0;
166 
167   size_t chunk = EVP_MD_size(md);
168 
169   HMAC_CTX_init(&ctx);
170   HMAC_CTX_init(&ctx_tmp);
171   HMAC_CTX_init(&ctx_init);
172   if (!HMAC_Init_ex(&ctx_init, secret, secret_len, md, NULL) ||
173       !HMAC_CTX_copy_ex(&ctx, &ctx_init) ||
174       !HMAC_Update(&ctx, seed1, seed1_len) ||
175       !HMAC_Update(&ctx, seed2, seed2_len) ||
176       !HMAC_Update(&ctx, seed3, seed3_len) ||
177       !HMAC_Final(&ctx, A1, &A1_len)) {
178     goto err;
179   }
180 
181   for (;;) {
182     unsigned len;
183     uint8_t hmac[EVP_MAX_MD_SIZE];
184     if (!HMAC_CTX_copy_ex(&ctx, &ctx_init) ||
185         !HMAC_Update(&ctx, A1, A1_len) ||
186         /* Save a copy of |ctx| to compute the next A1 value below. */
187         (out_len > chunk && !HMAC_CTX_copy_ex(&ctx_tmp, &ctx)) ||
188         !HMAC_Update(&ctx, seed1, seed1_len) ||
189         !HMAC_Update(&ctx, seed2, seed2_len) ||
190         !HMAC_Update(&ctx, seed3, seed3_len) ||
191         !HMAC_Final(&ctx, hmac, &len)) {
192       goto err;
193     }
194     assert(len == chunk);
195 
196     /* XOR the result into |out|. */
197     if (len > out_len) {
198       len = out_len;
199     }
200     unsigned i;
201     for (i = 0; i < len; i++) {
202       out[i] ^= hmac[i];
203     }
204     out += len;
205     out_len -= len;
206 
207     if (out_len == 0) {
208       break;
209     }
210 
211     /* Calculate the next A1 value. */
212     if (!HMAC_Final(&ctx_tmp, A1, &A1_len)) {
213       goto err;
214     }
215   }
216 
217   ret = 1;
218 
219 err:
220   HMAC_CTX_cleanup(&ctx);
221   HMAC_CTX_cleanup(&ctx_tmp);
222   HMAC_CTX_cleanup(&ctx_init);
223   OPENSSL_cleanse(A1, sizeof(A1));
224   return ret;
225 }
226 
tls1_prf(SSL * ssl,uint8_t * out,size_t out_len,const uint8_t * secret,size_t secret_len,const char * label,size_t label_len,const uint8_t * seed1,size_t seed1_len,const uint8_t * seed2,size_t seed2_len)227 int tls1_prf(SSL *ssl, uint8_t *out, size_t out_len, const uint8_t *secret,
228              size_t secret_len, const char *label, size_t label_len,
229              const uint8_t *seed1, size_t seed1_len,
230              const uint8_t *seed2, size_t seed2_len) {
231 
232   if (out_len == 0) {
233     return 1;
234   }
235 
236   memset(out, 0, out_len);
237 
238   uint32_t algorithm_prf = ssl_get_algorithm_prf(ssl);
239   if (algorithm_prf == SSL_HANDSHAKE_MAC_DEFAULT) {
240     /* If using the MD5/SHA1 PRF, |secret| is partitioned between SHA-1 and
241      * MD5, MD5 first. */
242     size_t secret_half = secret_len - (secret_len / 2);
243     if (!tls1_P_hash(out, out_len, EVP_md5(), secret, secret_half,
244                      (const uint8_t *)label, label_len, seed1, seed1_len, seed2,
245                      seed2_len)) {
246       return 0;
247     }
248 
249     /* Note that, if |secret_len| is odd, the two halves share a byte. */
250     secret = secret + (secret_len - secret_half);
251     secret_len = secret_half;
252   }
253 
254   if (!tls1_P_hash(out, out_len, ssl_get_handshake_digest(algorithm_prf),
255                    secret, secret_len, (const uint8_t *)label, label_len,
256                    seed1, seed1_len, seed2, seed2_len)) {
257     return 0;
258   }
259 
260   return 1;
261 }
262 
tls1_generate_key_block(SSL * ssl,uint8_t * out,size_t out_len)263 static int tls1_generate_key_block(SSL *ssl, uint8_t *out, size_t out_len) {
264   return ssl->enc_method->prf(
265       ssl, out, out_len, ssl->session->master_key,
266       ssl->session->master_key_length, TLS_MD_KEY_EXPANSION_CONST,
267       TLS_MD_KEY_EXPANSION_CONST_SIZE, ssl->s3->server_random, SSL3_RANDOM_SIZE,
268       ssl->s3->client_random, SSL3_RANDOM_SIZE);
269 }
270 
tls1_change_cipher_state(SSL * ssl,int which)271 int tls1_change_cipher_state(SSL *ssl, int which) {
272   /* is_read is true if we have just read a ChangeCipherSpec message - i.e. we
273    * need to update the read cipherspec. Otherwise we have just written one. */
274   const char is_read = (which & SSL3_CC_READ) != 0;
275   /* use_client_keys is true if we wish to use the keys for the "client write"
276    * direction. This is the case if we're a client sending a ChangeCipherSpec,
277    * or a server reading a client's ChangeCipherSpec. */
278   const char use_client_keys = which == SSL3_CHANGE_CIPHER_CLIENT_WRITE ||
279                                which == SSL3_CHANGE_CIPHER_SERVER_READ;
280   const uint8_t *client_write_mac_secret, *server_write_mac_secret, *mac_secret;
281   const uint8_t *client_write_key, *server_write_key, *key;
282   const uint8_t *client_write_iv, *server_write_iv, *iv;
283   const EVP_AEAD *aead = ssl->s3->tmp.new_aead;
284   size_t key_len, iv_len, mac_secret_len;
285   const uint8_t *key_data;
286 
287   /* Reset sequence number to zero. */
288   if (is_read) {
289     if (SSL_IS_DTLS(ssl)) {
290       ssl->d1->r_epoch++;
291       memset(&ssl->d1->bitmap, 0, sizeof(ssl->d1->bitmap));
292     }
293     memset(ssl->s3->read_sequence, 0, sizeof(ssl->s3->read_sequence));
294   } else {
295     if (SSL_IS_DTLS(ssl)) {
296       ssl->d1->w_epoch++;
297       memcpy(ssl->d1->last_write_sequence, ssl->s3->write_sequence,
298              sizeof(ssl->s3->write_sequence));
299     }
300     memset(ssl->s3->write_sequence, 0, sizeof(ssl->s3->write_sequence));
301   }
302 
303   mac_secret_len = ssl->s3->tmp.new_mac_secret_len;
304   iv_len = ssl->s3->tmp.new_fixed_iv_len;
305 
306   if (aead == NULL) {
307     OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
308     return 0;
309   }
310 
311   key_len = EVP_AEAD_key_length(aead);
312   if (mac_secret_len > 0) {
313     /* For "stateful" AEADs (i.e. compatibility with pre-AEAD cipher
314      * suites) the key length reported by |EVP_AEAD_key_length| will
315      * include the MAC and IV key bytes. */
316     if (key_len < mac_secret_len + iv_len) {
317       OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
318       return 0;
319     }
320     key_len -= mac_secret_len + iv_len;
321   }
322 
323   key_data = ssl->s3->tmp.key_block;
324   client_write_mac_secret = key_data;
325   key_data += mac_secret_len;
326   server_write_mac_secret = key_data;
327   key_data += mac_secret_len;
328   client_write_key = key_data;
329   key_data += key_len;
330   server_write_key = key_data;
331   key_data += key_len;
332   client_write_iv = key_data;
333   key_data += iv_len;
334   server_write_iv = key_data;
335   key_data += iv_len;
336 
337   if (use_client_keys) {
338     mac_secret = client_write_mac_secret;
339     key = client_write_key;
340     iv = client_write_iv;
341   } else {
342     mac_secret = server_write_mac_secret;
343     key = server_write_key;
344     iv = server_write_iv;
345   }
346 
347   if (key_data - ssl->s3->tmp.key_block != ssl->s3->tmp.key_block_length) {
348     OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
349     return 0;
350   }
351 
352   if (is_read) {
353     SSL_AEAD_CTX_free(ssl->aead_read_ctx);
354     ssl->aead_read_ctx = SSL_AEAD_CTX_new(
355         evp_aead_open, ssl3_version_from_wire(ssl, ssl->version),
356         ssl->s3->tmp.new_cipher, key, key_len, mac_secret, mac_secret_len, iv,
357         iv_len);
358     return ssl->aead_read_ctx != NULL;
359   }
360 
361   SSL_AEAD_CTX_free(ssl->aead_write_ctx);
362   ssl->aead_write_ctx = SSL_AEAD_CTX_new(
363       evp_aead_seal, ssl3_version_from_wire(ssl, ssl->version),
364       ssl->s3->tmp.new_cipher, key, key_len, mac_secret, mac_secret_len, iv,
365       iv_len);
366   return ssl->aead_write_ctx != NULL;
367 }
368 
tls1_setup_key_block(SSL * ssl)369 int tls1_setup_key_block(SSL *ssl) {
370   uint8_t *p;
371   const EVP_AEAD *aead = NULL;
372   int ret = 0;
373   size_t mac_secret_len, fixed_iv_len, variable_iv_len, key_len;
374   size_t key_block_len;
375 
376   if (ssl->s3->tmp.key_block_length != 0) {
377     return 1;
378   }
379 
380   if (ssl->session->cipher == NULL) {
381     goto cipher_unavailable_err;
382   }
383 
384   if (!ssl_cipher_get_evp_aead(&aead, &mac_secret_len, &fixed_iv_len,
385                                ssl->session->cipher,
386                                ssl3_version_from_wire(ssl, ssl->version))) {
387     goto cipher_unavailable_err;
388   }
389   key_len = EVP_AEAD_key_length(aead);
390   variable_iv_len = EVP_AEAD_nonce_length(aead);
391   if (mac_secret_len > 0) {
392     /* For "stateful" AEADs (i.e. compatibility with pre-AEAD cipher suites) the
393      * key length reported by |EVP_AEAD_key_length| will include the MAC key
394      * bytes and initial implicit IV. */
395     if (key_len < mac_secret_len + fixed_iv_len) {
396       OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
397       return 0;
398     }
399     key_len -= mac_secret_len + fixed_iv_len;
400   } else {
401     /* The nonce is split into a fixed portion and a variable portion. */
402     if (variable_iv_len < fixed_iv_len) {
403       OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
404       return 0;
405     }
406     variable_iv_len -= fixed_iv_len;
407   }
408 
409   assert(mac_secret_len < 256);
410   assert(fixed_iv_len < 256);
411   assert(variable_iv_len < 256);
412 
413   ssl->s3->tmp.new_aead = aead;
414   ssl->s3->tmp.new_mac_secret_len = (uint8_t)mac_secret_len;
415   ssl->s3->tmp.new_fixed_iv_len = (uint8_t)fixed_iv_len;
416   ssl->s3->tmp.new_variable_iv_len = (uint8_t)variable_iv_len;
417 
418   key_block_len = key_len + mac_secret_len + fixed_iv_len;
419   key_block_len *= 2;
420 
421   ssl3_cleanup_key_block(ssl);
422 
423   p = (uint8_t *)OPENSSL_malloc(key_block_len);
424   if (p == NULL) {
425     OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
426     goto err;
427   }
428 
429   ssl->s3->tmp.key_block_length = key_block_len;
430   ssl->s3->tmp.key_block = p;
431 
432   if (!tls1_generate_key_block(ssl, p, key_block_len)) {
433     goto err;
434   }
435 
436   ret = 1;
437 
438 err:
439   return ret;
440 
441 cipher_unavailable_err:
442   OPENSSL_PUT_ERROR(SSL, SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
443   return 0;
444 }
445 
tls1_cert_verify_mac(SSL * ssl,int md_nid,uint8_t * out)446 int tls1_cert_verify_mac(SSL *ssl, int md_nid, uint8_t *out) {
447   const EVP_MD_CTX *ctx_template;
448   if (md_nid == NID_md5) {
449     ctx_template = &ssl->s3->handshake_md5;
450   } else if (md_nid == EVP_MD_CTX_type(&ssl->s3->handshake_hash)) {
451     ctx_template = &ssl->s3->handshake_hash;
452   } else {
453     OPENSSL_PUT_ERROR(SSL, SSL_R_NO_REQUIRED_DIGEST);
454     return 0;
455   }
456 
457   EVP_MD_CTX ctx;
458   EVP_MD_CTX_init(&ctx);
459   if (!EVP_MD_CTX_copy_ex(&ctx, ctx_template)) {
460     EVP_MD_CTX_cleanup(&ctx);
461     return 0;
462   }
463   unsigned ret;
464   EVP_DigestFinal_ex(&ctx, out, &ret);
465   EVP_MD_CTX_cleanup(&ctx);
466   return ret;
467 }
468 
append_digest(const EVP_MD_CTX * ctx,uint8_t * out,size_t * out_len,size_t max_out)469 static int append_digest(const EVP_MD_CTX *ctx, uint8_t *out, size_t *out_len,
470                          size_t max_out) {
471   int ret = 0;
472   EVP_MD_CTX ctx_copy;
473   EVP_MD_CTX_init(&ctx_copy);
474 
475   if (EVP_MD_CTX_size(ctx) > max_out) {
476     OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL);
477     goto err;
478   }
479   unsigned len;
480   if (!EVP_MD_CTX_copy_ex(&ctx_copy, ctx) ||
481       !EVP_DigestFinal_ex(&ctx_copy, out, &len)) {
482     goto err;
483   }
484   assert(len == EVP_MD_CTX_size(ctx));
485 
486   *out_len = len;
487   ret = 1;
488 
489 err:
490   EVP_MD_CTX_cleanup(&ctx_copy);
491   return ret;
492 }
493 
494 /* tls1_handshake_digest calculates the current handshake hash and writes it to
495  * |out|, which has space for |out_len| bytes. It returns the number of bytes
496  * written or -1 in the event of an error. This function works on a copy of the
497  * underlying digests so can be called multiple times and prior to the final
498  * update etc. */
tls1_handshake_digest(SSL * ssl,uint8_t * out,size_t out_len)499 int tls1_handshake_digest(SSL *ssl, uint8_t *out, size_t out_len) {
500   size_t md5_len = 0;
501   if (EVP_MD_CTX_md(&ssl->s3->handshake_md5) != NULL &&
502       !append_digest(&ssl->s3->handshake_md5, out, &md5_len, out_len)) {
503     return -1;
504   }
505 
506   size_t len;
507   if (!append_digest(&ssl->s3->handshake_hash, out + md5_len, &len,
508                      out_len - md5_len)) {
509     return -1;
510   }
511 
512   return (int)(md5_len + len);
513 }
514 
tls1_final_finish_mac(SSL * ssl,const char * str,int slen,uint8_t * out)515 int tls1_final_finish_mac(SSL *ssl, const char *str, int slen, uint8_t *out) {
516   uint8_t buf[2 * EVP_MAX_MD_SIZE];
517   int err = 0;
518   int digests_len;
519 
520   /* At this point, the handshake should have released the handshake buffer on
521    * its own. */
522   assert(ssl->s3->handshake_buffer == NULL);
523 
524   digests_len = tls1_handshake_digest(ssl, buf, sizeof(buf));
525   if (digests_len < 0) {
526     err = 1;
527     digests_len = 0;
528   }
529 
530   if (!ssl->enc_method->prf(ssl, out, 12, ssl->session->master_key,
531                             ssl->session->master_key_length, str, slen, buf,
532                             digests_len, NULL, 0)) {
533     err = 1;
534   }
535 
536   if (err) {
537     return 0;
538   } else {
539     return 12;
540   }
541 }
542 
tls1_generate_master_secret(SSL * ssl,uint8_t * out,const uint8_t * premaster,size_t premaster_len)543 int tls1_generate_master_secret(SSL *ssl, uint8_t *out,
544                                 const uint8_t *premaster,
545                                 size_t premaster_len) {
546   if (ssl->s3->tmp.extended_master_secret) {
547     uint8_t digests[2 * EVP_MAX_MD_SIZE];
548     int digests_len = tls1_handshake_digest(ssl, digests, sizeof(digests));
549     if (digests_len == -1) {
550       return 0;
551     }
552 
553     if (!ssl->enc_method->prf(ssl, out, SSL3_MASTER_SECRET_SIZE, premaster,
554                               premaster_len,
555                               TLS_MD_EXTENDED_MASTER_SECRET_CONST,
556                               TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE, digests,
557                               digests_len, NULL, 0)) {
558       return 0;
559     }
560   } else {
561     if (!ssl->enc_method->prf(ssl, out, SSL3_MASTER_SECRET_SIZE, premaster,
562                               premaster_len, TLS_MD_MASTER_SECRET_CONST,
563                               TLS_MD_MASTER_SECRET_CONST_SIZE,
564                               ssl->s3->client_random, SSL3_RANDOM_SIZE,
565                               ssl->s3->server_random, SSL3_RANDOM_SIZE)) {
566       return 0;
567     }
568   }
569 
570   return SSL3_MASTER_SECRET_SIZE;
571 }
572 
tls1_export_keying_material(SSL * ssl,uint8_t * out,size_t out_len,const char * label,size_t label_len,const uint8_t * context,size_t context_len,int use_context)573 int tls1_export_keying_material(SSL *ssl, uint8_t *out, size_t out_len,
574                                 const char *label, size_t label_len,
575                                 const uint8_t *context, size_t context_len,
576                                 int use_context) {
577   if (!ssl->s3->have_version || ssl->version == SSL3_VERSION) {
578     OPENSSL_PUT_ERROR(SSL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
579     return 0;
580   }
581 
582   size_t seed_len = 2 * SSL3_RANDOM_SIZE;
583   if (use_context) {
584     if (context_len >= 1u << 16) {
585       OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
586       return 0;
587     }
588     seed_len += 2 + context_len;
589   }
590   uint8_t *seed = OPENSSL_malloc(seed_len);
591   if (seed == NULL) {
592     OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
593     return 0;
594   }
595 
596   memcpy(seed, ssl->s3->client_random, SSL3_RANDOM_SIZE);
597   memcpy(seed + SSL3_RANDOM_SIZE, ssl->s3->server_random, SSL3_RANDOM_SIZE);
598   if (use_context) {
599     seed[2 * SSL3_RANDOM_SIZE] = (uint8_t)(context_len >> 8);
600     seed[2 * SSL3_RANDOM_SIZE + 1] = (uint8_t)context_len;
601     memcpy(seed + 2 * SSL3_RANDOM_SIZE + 2, context, context_len);
602   }
603 
604   int ret = ssl->enc_method->prf(ssl, out, out_len, ssl->session->master_key,
605                                  ssl->session->master_key_length, label,
606                                  label_len, seed, seed_len, NULL, 0);
607   OPENSSL_free(seed);
608   return ret;
609 }
610 
tls1_alert_code(int code)611 int tls1_alert_code(int code) {
612   switch (code) {
613     case SSL_AD_CLOSE_NOTIFY:
614       return SSL3_AD_CLOSE_NOTIFY;
615 
616     case SSL_AD_UNEXPECTED_MESSAGE:
617       return SSL3_AD_UNEXPECTED_MESSAGE;
618 
619     case SSL_AD_BAD_RECORD_MAC:
620       return SSL3_AD_BAD_RECORD_MAC;
621 
622     case SSL_AD_DECRYPTION_FAILED:
623       return TLS1_AD_DECRYPTION_FAILED;
624 
625     case SSL_AD_RECORD_OVERFLOW:
626       return TLS1_AD_RECORD_OVERFLOW;
627 
628     case SSL_AD_DECOMPRESSION_FAILURE:
629       return SSL3_AD_DECOMPRESSION_FAILURE;
630 
631     case SSL_AD_HANDSHAKE_FAILURE:
632       return SSL3_AD_HANDSHAKE_FAILURE;
633 
634     case SSL_AD_NO_CERTIFICATE:
635       return -1;
636 
637     case SSL_AD_BAD_CERTIFICATE:
638       return SSL3_AD_BAD_CERTIFICATE;
639 
640     case SSL_AD_UNSUPPORTED_CERTIFICATE:
641       return SSL3_AD_UNSUPPORTED_CERTIFICATE;
642 
643     case SSL_AD_CERTIFICATE_REVOKED:
644       return SSL3_AD_CERTIFICATE_REVOKED;
645 
646     case SSL_AD_CERTIFICATE_EXPIRED:
647       return SSL3_AD_CERTIFICATE_EXPIRED;
648 
649     case SSL_AD_CERTIFICATE_UNKNOWN:
650       return SSL3_AD_CERTIFICATE_UNKNOWN;
651 
652     case SSL_AD_ILLEGAL_PARAMETER:
653       return SSL3_AD_ILLEGAL_PARAMETER;
654 
655     case SSL_AD_UNKNOWN_CA:
656       return TLS1_AD_UNKNOWN_CA;
657 
658     case SSL_AD_ACCESS_DENIED:
659       return TLS1_AD_ACCESS_DENIED;
660 
661     case SSL_AD_DECODE_ERROR:
662       return TLS1_AD_DECODE_ERROR;
663 
664     case SSL_AD_DECRYPT_ERROR:
665       return TLS1_AD_DECRYPT_ERROR;
666     case SSL_AD_EXPORT_RESTRICTION:
667       return TLS1_AD_EXPORT_RESTRICTION;
668 
669     case SSL_AD_PROTOCOL_VERSION:
670       return TLS1_AD_PROTOCOL_VERSION;
671 
672     case SSL_AD_INSUFFICIENT_SECURITY:
673       return TLS1_AD_INSUFFICIENT_SECURITY;
674 
675     case SSL_AD_INTERNAL_ERROR:
676       return TLS1_AD_INTERNAL_ERROR;
677 
678     case SSL_AD_USER_CANCELLED:
679       return TLS1_AD_USER_CANCELLED;
680 
681     case SSL_AD_NO_RENEGOTIATION:
682       return TLS1_AD_NO_RENEGOTIATION;
683 
684     case SSL_AD_UNSUPPORTED_EXTENSION:
685       return TLS1_AD_UNSUPPORTED_EXTENSION;
686 
687     case SSL_AD_CERTIFICATE_UNOBTAINABLE:
688       return TLS1_AD_CERTIFICATE_UNOBTAINABLE;
689 
690     case SSL_AD_UNRECOGNIZED_NAME:
691       return TLS1_AD_UNRECOGNIZED_NAME;
692 
693     case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
694       return TLS1_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
695 
696     case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
697       return TLS1_AD_BAD_CERTIFICATE_HASH_VALUE;
698 
699     case SSL_AD_UNKNOWN_PSK_IDENTITY:
700       return TLS1_AD_UNKNOWN_PSK_IDENTITY;
701 
702     case SSL_AD_INAPPROPRIATE_FALLBACK:
703       return SSL3_AD_INAPPROPRIATE_FALLBACK;
704 
705     default:
706       return -1;
707   }
708 }
709