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 <string.h>
140
141#include <utility>
142
143#include <openssl/err.h>
144#include <openssl/evp.h>
145#include <openssl/hmac.h>
146#include <openssl/md5.h>
147#include <openssl/mem.h>
148#include <openssl/nid.h>
149#include <openssl/rand.h>
150
151#include "../crypto/fipsmodule/tls/internal.h"
152#include "../crypto/internal.h"
153#include "internal.h"
154
155
156namespace bssl {
157
158bool tls1_prf(const EVP_MD *digest, Span<uint8_t> out,
159              Span<const uint8_t> secret, Span<const char> label,
160              Span<const uint8_t> seed1, Span<const uint8_t> seed2) {
161  return 1 == CRYPTO_tls1_prf(digest, out.data(), out.size(), secret.data(),
162                              secret.size(), label.data(), label.size(),
163                              seed1.data(), seed1.size(), seed2.data(),
164                              seed2.size());
165}
166
167static bool ssl3_prf(Span<uint8_t> out, Span<const uint8_t> secret,
168                     Span<const char> label, Span<const uint8_t> seed1,
169                     Span<const uint8_t> seed2) {
170  ScopedEVP_MD_CTX md5;
171  ScopedEVP_MD_CTX sha1;
172  uint8_t buf[16], smd[SHA_DIGEST_LENGTH];
173  uint8_t c = 'A';
174  size_t k = 0;
175  while (!out.empty()) {
176    k++;
177    if (k > sizeof(buf)) {
178      // bug: 'buf' is too small for this ciphersuite
179      OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
180      return false;
181    }
182
183    for (size_t j = 0; j < k; j++) {
184      buf[j] = c;
185    }
186    c++;
187    if (!EVP_DigestInit_ex(sha1.get(), EVP_sha1(), NULL)) {
188      OPENSSL_PUT_ERROR(SSL, ERR_LIB_EVP);
189      return false;
190    }
191    EVP_DigestUpdate(sha1.get(), buf, k);
192    EVP_DigestUpdate(sha1.get(), secret.data(), secret.size());
193    // |label| is ignored for SSLv3.
194    EVP_DigestUpdate(sha1.get(), seed1.data(), seed1.size());
195    EVP_DigestUpdate(sha1.get(), seed2.data(), seed2.size());
196    EVP_DigestFinal_ex(sha1.get(), smd, NULL);
197
198    if (!EVP_DigestInit_ex(md5.get(), EVP_md5(), NULL)) {
199      OPENSSL_PUT_ERROR(SSL, ERR_LIB_EVP);
200      return false;
201    }
202    EVP_DigestUpdate(md5.get(), secret.data(), secret.size());
203    EVP_DigestUpdate(md5.get(), smd, SHA_DIGEST_LENGTH);
204    if (out.size() < MD5_DIGEST_LENGTH) {
205      EVP_DigestFinal_ex(md5.get(), smd, NULL);
206      OPENSSL_memcpy(out.data(), smd, out.size());
207      break;
208    }
209    EVP_DigestFinal_ex(md5.get(), out.data(), NULL);
210    out = out.subspan(MD5_DIGEST_LENGTH);
211  }
212
213  OPENSSL_cleanse(smd, SHA_DIGEST_LENGTH);
214  return true;
215}
216
217static bool get_key_block_lengths(const SSL *ssl, size_t *out_mac_secret_len,
218                                  size_t *out_key_len, size_t *out_iv_len,
219                                  const SSL_CIPHER *cipher) {
220  const EVP_AEAD *aead = NULL;
221  if (!ssl_cipher_get_evp_aead(&aead, out_mac_secret_len, out_iv_len, cipher,
222                               ssl_protocol_version(ssl), SSL_is_dtls(ssl))) {
223    OPENSSL_PUT_ERROR(SSL, SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
224    return false;
225  }
226
227  *out_key_len = EVP_AEAD_key_length(aead);
228  if (*out_mac_secret_len > 0) {
229    // For "stateful" AEADs (i.e. compatibility with pre-AEAD cipher suites) the
230    // key length reported by |EVP_AEAD_key_length| will include the MAC key
231    // bytes and initial implicit IV.
232    if (*out_key_len < *out_mac_secret_len + *out_iv_len) {
233      OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
234      return false;
235    }
236    *out_key_len -= *out_mac_secret_len + *out_iv_len;
237  }
238
239  return true;
240}
241
242int tls1_configure_aead(SSL *ssl, evp_aead_direction_t direction,
243                        Array<uint8_t> *key_block_cache,
244                        const SSL_CIPHER *cipher,
245                        Span<const uint8_t> iv_override) {
246  size_t mac_secret_len, key_len, iv_len;
247  if (!get_key_block_lengths(ssl, &mac_secret_len, &key_len, &iv_len, cipher)) {
248    return 0;
249  }
250
251  // Ensure that |key_block_cache| is set up.
252  const size_t key_block_size = 2 * (mac_secret_len + key_len + iv_len);
253  if (key_block_cache->empty()) {
254    if (!key_block_cache->Init(key_block_size) ||
255        !SSL_generate_key_block(ssl, key_block_cache->data(), key_block_size)) {
256      return 0;
257    }
258  }
259  assert(key_block_cache->size() == key_block_size);
260
261  Span<const uint8_t> key_block = *key_block_cache;
262  Span<const uint8_t> mac_secret, key, iv;
263  if (direction == (ssl->server ? evp_aead_open : evp_aead_seal)) {
264    // Use the client write (server read) keys.
265    mac_secret = key_block.subspan(0, mac_secret_len);
266    key = key_block.subspan(2 * mac_secret_len, key_len);
267    iv = key_block.subspan(2 * mac_secret_len + 2 * key_len, iv_len);
268  } else {
269    // Use the server write (client read) keys.
270    mac_secret = key_block.subspan(mac_secret_len, mac_secret_len);
271    key = key_block.subspan(2 * mac_secret_len + key_len, key_len);
272    iv = key_block.subspan(2 * mac_secret_len + 2 * key_len + iv_len, iv_len);
273  }
274
275  if (!iv_override.empty()) {
276    if (iv_override.size() != iv_len) {
277      return 0;
278    }
279    iv = iv_override;
280  }
281
282  UniquePtr<SSLAEADContext> aead_ctx = SSLAEADContext::Create(
283      direction, ssl->version, SSL_is_dtls(ssl), cipher, key, mac_secret, iv);
284  if (!aead_ctx) {
285    return 0;
286  }
287
288  if (direction == evp_aead_open) {
289    return ssl->method->set_read_state(ssl, std::move(aead_ctx));
290  }
291
292  return ssl->method->set_write_state(ssl, std::move(aead_ctx));
293}
294
295int tls1_change_cipher_state(SSL_HANDSHAKE *hs,
296                             evp_aead_direction_t direction) {
297  return tls1_configure_aead(hs->ssl, direction, &hs->key_block,
298                             hs->new_cipher, {});
299}
300
301int tls1_generate_master_secret(SSL_HANDSHAKE *hs, uint8_t *out,
302                                Span<const uint8_t> premaster) {
303  static const char kMasterSecretLabel[] = "master secret";
304  static const char kExtendedMasterSecretLabel[] = "extended master secret";
305
306  const SSL *ssl = hs->ssl;
307  auto out_span = MakeSpan(out, SSL3_MASTER_SECRET_SIZE);
308  if (hs->extended_master_secret) {
309    auto label = MakeConstSpan(kExtendedMasterSecretLabel,
310                               sizeof(kExtendedMasterSecretLabel) - 1);
311    uint8_t digests[EVP_MAX_MD_SIZE];
312    size_t digests_len;
313    if (!hs->transcript.GetHash(digests, &digests_len) ||
314        !tls1_prf(hs->transcript.Digest(), out_span, premaster, label,
315                  MakeConstSpan(digests, digests_len), {})) {
316      return 0;
317    }
318  } else {
319    auto label =
320        MakeConstSpan(kMasterSecretLabel, sizeof(kMasterSecretLabel) - 1);
321    if (ssl_protocol_version(ssl) == SSL3_VERSION) {
322      if (!ssl3_prf(out_span, premaster, label, ssl->s3->client_random,
323                    ssl->s3->server_random)) {
324        return 0;
325      }
326    } else {
327      if (!tls1_prf(hs->transcript.Digest(), out_span, premaster, label,
328                    ssl->s3->client_random, ssl->s3->server_random)) {
329        return 0;
330      }
331    }
332  }
333
334  return SSL3_MASTER_SECRET_SIZE;
335}
336
337}  // namespace bssl
338
339using namespace bssl;
340
341size_t SSL_get_key_block_len(const SSL *ssl) {
342  size_t mac_secret_len, key_len, fixed_iv_len;
343  if (!get_key_block_lengths(ssl, &mac_secret_len, &key_len, &fixed_iv_len,
344                             SSL_get_current_cipher(ssl))) {
345    ERR_clear_error();
346    return 0;
347  }
348
349  return 2 * (mac_secret_len + key_len + fixed_iv_len);
350}
351
352int SSL_generate_key_block(const SSL *ssl, uint8_t *out, size_t out_len) {
353  const SSL_SESSION *session = SSL_get_session(ssl);
354  auto out_span = MakeSpan(out, out_len);
355  auto master_key =
356      MakeConstSpan(session->master_key, session->master_key_length);
357  static const char kLabel[] = "key expansion";
358  auto label = MakeConstSpan(kLabel, sizeof(kLabel) - 1);
359
360  if (ssl_protocol_version(ssl) == SSL3_VERSION) {
361    return ssl3_prf(out_span, master_key, label, ssl->s3->server_random,
362                    ssl->s3->client_random);
363  }
364
365  const EVP_MD *digest = ssl_session_get_digest(session);
366  return tls1_prf(digest, out_span, master_key, label, ssl->s3->server_random,
367                  ssl->s3->client_random);
368}
369
370int SSL_export_keying_material(SSL *ssl, uint8_t *out, size_t out_len,
371                               const char *label, size_t label_len,
372                               const uint8_t *context, size_t context_len,
373                               int use_context) {
374  if (!ssl->s3->have_version || ssl->version == SSL3_VERSION) {
375    OPENSSL_PUT_ERROR(SSL, SSL_R_HANDSHAKE_NOT_COMPLETE);
376    return 0;
377  }
378
379  // Exporters may be used in False Start and server 0-RTT, where the handshake
380  // has progressed enough. Otherwise, they may not be used during a handshake.
381  if (SSL_in_init(ssl) &&
382      !SSL_in_false_start(ssl) &&
383      !(SSL_is_server(ssl) && SSL_in_early_data(ssl))) {
384    OPENSSL_PUT_ERROR(SSL, SSL_R_HANDSHAKE_NOT_COMPLETE);
385    return 0;
386  }
387
388  if (ssl_protocol_version(ssl) >= TLS1_3_VERSION) {
389    if (!use_context) {
390      context = nullptr;
391      context_len = 0;
392    }
393    return tls13_export_keying_material(
394        ssl, MakeSpan(out, out_len),
395        MakeConstSpan(ssl->s3->exporter_secret, ssl->s3->exporter_secret_len),
396        MakeConstSpan(label, label_len), MakeConstSpan(context, context_len));
397  }
398
399  size_t seed_len = 2 * SSL3_RANDOM_SIZE;
400  if (use_context) {
401    if (context_len >= 1u << 16) {
402      OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
403      return 0;
404    }
405    seed_len += 2 + context_len;
406  }
407  Array<uint8_t> seed;
408  if (!seed.Init(seed_len)) {
409    OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
410    return 0;
411  }
412
413  OPENSSL_memcpy(seed.data(), ssl->s3->client_random, SSL3_RANDOM_SIZE);
414  OPENSSL_memcpy(seed.data() + SSL3_RANDOM_SIZE, ssl->s3->server_random,
415                 SSL3_RANDOM_SIZE);
416  if (use_context) {
417    seed[2 * SSL3_RANDOM_SIZE] = static_cast<uint8_t>(context_len >> 8);
418    seed[2 * SSL3_RANDOM_SIZE + 1] = static_cast<uint8_t>(context_len);
419    OPENSSL_memcpy(seed.data() + 2 * SSL3_RANDOM_SIZE + 2, context, context_len);
420  }
421
422  const SSL_SESSION *session = SSL_get_session(ssl);
423  const EVP_MD *digest = ssl_session_get_digest(session);
424  return tls1_prf(
425      digest, MakeSpan(out, out_len),
426      MakeConstSpan(session->master_key, session->master_key_length),
427      MakeConstSpan(label, label_len), seed, {});
428}
429
430int SSL_export_early_keying_material(
431    SSL *ssl, uint8_t *out, size_t out_len, const char *label, size_t label_len,
432    const uint8_t *context, size_t context_len) {
433  if (!SSL_in_early_data(ssl) &&
434      (!ssl->s3->have_version ||
435       ssl_protocol_version(ssl) < TLS1_3_VERSION)) {
436    OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_SSL_VERSION);
437    return 0;
438  }
439
440  // The early exporter only exists if we accepted early data or offered it as
441  // a client.
442  if (!SSL_in_early_data(ssl) && !SSL_early_data_accepted(ssl)) {
443    OPENSSL_PUT_ERROR(SSL, SSL_R_EARLY_DATA_NOT_IN_USE);
444    return 0;
445  }
446
447  return tls13_export_keying_material(
448      ssl, MakeSpan(out, out_len),
449      MakeConstSpan(ssl->s3->early_exporter_secret,
450                    ssl->s3->early_exporter_secret_len),
451      MakeConstSpan(label, label_len), MakeConstSpan(context, context_len));
452}
453