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 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
112  * ECC cipher suite support in OpenSSL originally developed by
113  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
114  */
115 /* ====================================================================
116  * Copyright 2005 Nokia. All rights reserved.
117  *
118  * The portions of the attached software ("Contribution") is developed by
119  * Nokia Corporation and is licensed pursuant to the OpenSSL open source
120  * license.
121  *
122  * The Contribution, originally written by Mika Kousa and Pasi Eronen of
123  * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
124  * support (see RFC 4279) to OpenSSL.
125  *
126  * No patent licenses or other rights except those expressly stated in
127  * the OpenSSL open source license shall be deemed granted or received
128  * expressly, by implication, estoppel, or otherwise.
129  *
130  * No assurances are provided by Nokia that the Contribution does not
131  * infringe the patent or other intellectual property rights of any third
132  * party or that the license provides you with all the necessary rights
133  * to make use of the Contribution.
134  *
135  * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
136  * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
137  * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
138  * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
139  * OTHERWISE.
140  */
141 
142 #ifndef OPENSSL_HEADER_SSL_INTERNAL_H
143 #define OPENSSL_HEADER_SSL_INTERNAL_H
144 
145 #include <openssl/base.h>
146 
147 #include <openssl/aead.h>
148 #include <openssl/pqueue.h>
149 #include <openssl/ssl.h>
150 #include <openssl/stack.h>
151 
152 #if defined(OPENSSL_WINDOWS)
153 /* Windows defines struct timeval in winsock2.h. */
154 #pragma warning(push, 3)
155 #include <winsock2.h>
156 #pragma warning(pop)
157 #else
158 #include <sys/time.h>
159 #endif
160 
161 
162 /* Cipher suites. */
163 
164 /* Bits for |algorithm_mkey| (key exchange algorithm). */
165 #define SSL_kRSA 0x00000001L
166 #define SSL_kDHE 0x00000002L
167 #define SSL_kECDHE 0x00000004L
168 /* SSL_kPSK is only set for plain PSK, not ECDHE_PSK. */
169 #define SSL_kPSK 0x00000008L
170 
171 /* Bits for |algorithm_auth| (server authentication). */
172 #define SSL_aRSA 0x00000001L
173 #define SSL_aECDSA 0x00000002L
174 /* SSL_aPSK is set for both PSK and ECDHE_PSK. */
175 #define SSL_aPSK 0x00000004L
176 
177 /* Bits for |algorithm_enc| (symmetric encryption). */
178 #define SSL_3DES 0x00000001L
179 #define SSL_RC4 0x00000002L
180 #define SSL_AES128 0x00000004L
181 #define SSL_AES256 0x00000008L
182 #define SSL_AES128GCM 0x00000010L
183 #define SSL_AES256GCM 0x00000020L
184 #define SSL_CHACHA20POLY1305_OLD 0x00000040L
185 #define SSL_eNULL 0x00000080L
186 #define SSL_CHACHA20POLY1305 0x00000100L
187 
188 #define SSL_AES (SSL_AES128 | SSL_AES256 | SSL_AES128GCM | SSL_AES256GCM)
189 
190 /* Bits for |algorithm_mac| (symmetric authentication). */
191 #define SSL_MD5 0x00000001L
192 #define SSL_SHA1 0x00000002L
193 #define SSL_SHA256 0x00000004L
194 #define SSL_SHA384 0x00000008L
195 /* SSL_AEAD is set for all AEADs. */
196 #define SSL_AEAD 0x00000010L
197 
198 /* Bits for |algorithm_prf| (handshake digest). */
199 #define SSL_HANDSHAKE_MAC_DEFAULT 0x1
200 #define SSL_HANDSHAKE_MAC_SHA256 0x2
201 #define SSL_HANDSHAKE_MAC_SHA384 0x4
202 
203 /* SSL_MAX_DIGEST is the number of digest types which exist. When adding a new
204  * one, update the table in ssl_cipher.c. */
205 #define SSL_MAX_DIGEST 4
206 
207 /* ssl_cipher_get_evp_aead sets |*out_aead| to point to the correct EVP_AEAD
208  * object for |cipher| protocol version |version|. It sets |*out_mac_secret_len|
209  * and |*out_fixed_iv_len| to the MAC key length and fixed IV length,
210  * respectively. The MAC key length is zero except for legacy block and stream
211  * ciphers. It returns 1 on success and 0 on error. */
212 int ssl_cipher_get_evp_aead(const EVP_AEAD **out_aead,
213                             size_t *out_mac_secret_len,
214                             size_t *out_fixed_iv_len,
215                             const SSL_CIPHER *cipher, uint16_t version);
216 
217 /* ssl_get_handshake_digest returns the |EVP_MD| corresponding to
218  * |algorithm_prf|. It returns SHA-1 for |SSL_HANDSHAKE_DEFAULT|. The caller is
219  * responsible for maintaining the additional MD5 digest and switching to
220  * SHA-256 in TLS 1.2. */
221 const EVP_MD *ssl_get_handshake_digest(uint32_t algorithm_prf);
222 
223 /* ssl_create_cipher_list evaluates |rule_str| according to the ciphers in
224  * |ssl_method|. It sets |*out_cipher_list| to a newly-allocated
225  * |ssl_cipher_preference_list_st| containing the result.
226  * |*out_cipher_list_by_id| is set to a list of selected ciphers sorted by
227  * id. It returns |(*out_cipher_list)->ciphers| on success and NULL on
228  * failure. */
229 STACK_OF(SSL_CIPHER) *
230 ssl_create_cipher_list(const SSL_PROTOCOL_METHOD *ssl_method,
231                        struct ssl_cipher_preference_list_st **out_cipher_list,
232                        STACK_OF(SSL_CIPHER) **out_cipher_list_by_id,
233                        const char *rule_str);
234 
235 /* ssl_cipher_get_value returns the cipher suite id of |cipher|. */
236 uint16_t ssl_cipher_get_value(const SSL_CIPHER *cipher);
237 
238 /* ssl_cipher_get_key_type returns the |EVP_PKEY_*| value corresponding to the
239  * server key used in |cipher| or |EVP_PKEY_NONE| if there is none. */
240 int ssl_cipher_get_key_type(const SSL_CIPHER *cipher);
241 
242 /* ssl_cipher_has_server_public_key returns 1 if |cipher| involves a server
243  * public key in the key exchange, sent in a server Certificate message.
244  * Otherwise it returns 0. */
245 int ssl_cipher_has_server_public_key(const SSL_CIPHER *cipher);
246 
247 /* ssl_cipher_requires_server_key_exchange returns 1 if |cipher| requires a
248  * ServerKeyExchange message. Otherwise it returns 0.
249  *
250  * Unlike |ssl_cipher_has_server_public_key|, this function may return zero
251  * while still allowing |cipher| an optional ServerKeyExchange. This is the
252  * case for plain PSK ciphers. */
253 int ssl_cipher_requires_server_key_exchange(const SSL_CIPHER *cipher);
254 
255 /* ssl_cipher_get_record_split_len, for TLS 1.0 CBC mode ciphers, returns the
256  * length of an encrypted 1-byte record, for use in record-splitting. Otherwise
257  * it returns zero. */
258 size_t ssl_cipher_get_record_split_len(const SSL_CIPHER *cipher);
259 
260 
261 /* Encryption layer. */
262 
263 /* SSL_AEAD_CTX contains information about an AEAD that is being used to encrypt
264  * an SSL connection. */
265 struct ssl_aead_ctx_st {
266   const SSL_CIPHER *cipher;
267   EVP_AEAD_CTX ctx;
268   /* fixed_nonce contains any bytes of the nonce that are fixed for all
269    * records. */
270   uint8_t fixed_nonce[12];
271   uint8_t fixed_nonce_len, variable_nonce_len;
272   /* variable_nonce_included_in_record is non-zero if the variable nonce
273    * for a record is included as a prefix before the ciphertext. */
274   char variable_nonce_included_in_record;
275   /* random_variable_nonce is non-zero if the variable nonce is
276    * randomly generated, rather than derived from the sequence
277    * number. */
278   char random_variable_nonce;
279   /* omit_length_in_ad is non-zero if the length should be omitted in the
280    * AEAD's ad parameter. */
281   char omit_length_in_ad;
282   /* omit_version_in_ad is non-zero if the version should be omitted
283    * in the AEAD's ad parameter. */
284   char omit_version_in_ad;
285   /* xor_fixed_nonce is non-zero if the fixed nonce should be XOR'd into the
286    * variable nonce rather than prepended. */
287   char xor_fixed_nonce;
288 } /* SSL_AEAD_CTX */;
289 
290 /* SSL_AEAD_CTX_new creates a newly-allocated |SSL_AEAD_CTX| using the supplied
291  * key material. It returns NULL on error. Only one of |SSL_AEAD_CTX_open| or
292  * |SSL_AEAD_CTX_seal| may be used with the resulting object, depending on
293  * |direction|. |version| is the normalized protocol version, so DTLS 1.0 is
294  * represented as 0x0301, not 0xffef. */
295 SSL_AEAD_CTX *SSL_AEAD_CTX_new(enum evp_aead_direction_t direction,
296                                uint16_t version, const SSL_CIPHER *cipher,
297                                const uint8_t *enc_key, size_t enc_key_len,
298                                const uint8_t *mac_key, size_t mac_key_len,
299                                const uint8_t *fixed_iv, size_t fixed_iv_len);
300 
301 /* SSL_AEAD_CTX_free frees |ctx|. */
302 void SSL_AEAD_CTX_free(SSL_AEAD_CTX *ctx);
303 
304 /* SSL_AEAD_CTX_explicit_nonce_len returns the length of the explicit nonce for
305  * |ctx|, if any. |ctx| may be NULL to denote the null cipher. */
306 size_t SSL_AEAD_CTX_explicit_nonce_len(SSL_AEAD_CTX *ctx);
307 
308 /* SSL_AEAD_CTX_max_overhead returns the maximum overhead of calling
309  * |SSL_AEAD_CTX_seal|. |ctx| may be NULL to denote the null cipher. */
310 size_t SSL_AEAD_CTX_max_overhead(SSL_AEAD_CTX *ctx);
311 
312 /* SSL_AEAD_CTX_open authenticates and decrypts |in_len| bytes from |in| and
313  * writes the result to |out|. It returns one on success and zero on
314  * error. |ctx| may be NULL to denote the null cipher.
315  *
316  * If |in| and |out| alias then |out| must be <= |in| + |explicit_nonce_len|. */
317 int SSL_AEAD_CTX_open(SSL_AEAD_CTX *ctx, uint8_t *out, size_t *out_len,
318                       size_t max_out, uint8_t type, uint16_t wire_version,
319                       const uint8_t seqnum[8], const uint8_t *in,
320                       size_t in_len);
321 
322 /* SSL_AEAD_CTX_seal encrypts and authenticates |in_len| bytes from |in| and
323  * writes the result to |out|. It returns one on success and zero on
324  * error. |ctx| may be NULL to denote the null cipher.
325  *
326  * If |in| and |out| alias then |out| + |explicit_nonce_len| must be <= |in| */
327 int SSL_AEAD_CTX_seal(SSL_AEAD_CTX *ctx, uint8_t *out, size_t *out_len,
328                       size_t max_out, uint8_t type, uint16_t wire_version,
329                       const uint8_t seqnum[8], const uint8_t *in,
330                       size_t in_len);
331 
332 
333 /* DTLS replay bitmap. */
334 
335 /* DTLS1_BITMAP maintains a sliding window of 64 sequence numbers to detect
336  * replayed packets. It should be initialized by zeroing every field. */
337 typedef struct dtls1_bitmap_st {
338   /* map is a bit mask of the last 64 sequence numbers. Bit
339    * |1<<i| corresponds to |max_seq_num - i|. */
340   uint64_t map;
341   /* max_seq_num is the largest sequence number seen so far as a 64-bit
342    * integer. */
343   uint64_t max_seq_num;
344 } DTLS1_BITMAP;
345 
346 
347 /* Record layer. */
348 
349 /* ssl_record_prefix_len returns the length of the prefix before the ciphertext
350  * of a record for |ssl|.
351  *
352  * TODO(davidben): Expose this as part of public API once the high-level
353  * buffer-free APIs are available. */
354 size_t ssl_record_prefix_len(const SSL *ssl);
355 
356 enum ssl_open_record_t {
357   ssl_open_record_success,
358   ssl_open_record_discard,
359   ssl_open_record_partial,
360   ssl_open_record_error,
361 };
362 
363 /* tls_open_record decrypts a record from |in|.
364  *
365  * On success, it returns |ssl_open_record_success|. It sets |*out_type| to the
366  * record type, |*out_len| to the plaintext length, and writes the record body
367  * to |out|. It sets |*out_consumed| to the number of bytes of |in| consumed.
368  * Note that |*out_len| may be zero.
369  *
370  * If a record was successfully processed but should be discarded, it returns
371  * |ssl_open_record_discard| and sets |*out_consumed| to the number of bytes
372  * consumed.
373  *
374  * If the input did not contain a complete record, it returns
375  * |ssl_open_record_partial|. It sets |*out_consumed| to the total number of
376  * bytes necessary. It is guaranteed that a successful call to |tls_open_record|
377  * will consume at least that many bytes.
378  *
379  * On failure, it returns |ssl_open_record_error| and sets |*out_alert| to an
380  * alert to emit.
381  *
382  * If |in| and |out| alias, |out| must be <= |in| + |ssl_record_prefix_len|. */
383 enum ssl_open_record_t tls_open_record(
384     SSL *ssl, uint8_t *out_type, uint8_t *out, size_t *out_len,
385     size_t *out_consumed, uint8_t *out_alert, size_t max_out, const uint8_t *in,
386     size_t in_len);
387 
388 /* dtls_open_record implements |tls_open_record| for DTLS. It never returns
389  * |ssl_open_record_partial| but otherwise behaves analogously. */
390 enum ssl_open_record_t dtls_open_record(
391     SSL *ssl, uint8_t *out_type, uint8_t *out, size_t *out_len,
392     size_t *out_consumed, uint8_t *out_alert, size_t max_out, const uint8_t *in,
393     size_t in_len);
394 
395 /* ssl_seal_prefix_len returns the length of the prefix before the ciphertext
396  * when sealing a record with |ssl|. Note that this value may differ from
397  * |ssl_record_prefix_len| when TLS 1.0 CBC record-splitting is enabled. Sealing
398  * a small record may also result in a smaller output than this value.
399  *
400  * TODO(davidben): Expose this as part of public API once the high-level
401  * buffer-free APIs are available. */
402 size_t ssl_seal_prefix_len(const SSL *ssl);
403 
404 /* ssl_max_seal_overhead returns the maximum overhead of sealing a record with
405  * |ssl|. This includes |ssl_seal_prefix_len|.
406  *
407  * TODO(davidben): Expose this as part of public API once the high-level
408  * buffer-free APIs are available. */
409 size_t ssl_max_seal_overhead(const SSL *ssl);
410 
411 /* tls_seal_record seals a new record of type |type| and body |in| and writes it
412  * to |out|. At most |max_out| bytes will be written. It returns one on success
413  * and zero on error. If enabled, |tls_seal_record| implements TLS 1.0 CBC 1/n-1
414  * record splitting and may write two records concatenated.
415  *
416  * For a large record, the ciphertext will begin |ssl_seal_prefix_len| bytes
417  * into out. Aligning |out| appropriately may improve performance. It writes at
418  * most |in_len| + |ssl_max_seal_overhead| bytes to |out|.
419  *
420  * If |in| and |out| alias, |out| + |ssl_seal_prefix_len| must be <= |in|. */
421 int tls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
422                     uint8_t type, const uint8_t *in, size_t in_len);
423 
424 enum dtls1_use_epoch_t {
425   dtls1_use_previous_epoch,
426   dtls1_use_current_epoch,
427 };
428 
429 /* dtls_seal_record implements |tls_seal_record| for DTLS. |use_epoch| selects
430  * which epoch's cipher state to use. */
431 int dtls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
432                      uint8_t type, const uint8_t *in, size_t in_len,
433                      enum dtls1_use_epoch_t use_epoch);
434 
435 
436 /* Private key operations. */
437 
438 /* ssl_has_private_key returns one if |ssl| has a private key
439  * configured and zero otherwise. */
440 int ssl_has_private_key(SSL *ssl);
441 
442 /* ssl_private_key_* call the corresponding function on the
443  * |SSL_PRIVATE_KEY_METHOD| for |ssl|, if configured. Otherwise, they implement
444  * the operation with |EVP_PKEY|. */
445 
446 int ssl_private_key_type(SSL *ssl);
447 
448 size_t ssl_private_key_max_signature_len(SSL *ssl);
449 
450 enum ssl_private_key_result_t ssl_private_key_sign(
451     SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out, const EVP_MD *md,
452     const uint8_t *in, size_t in_len);
453 
454 enum ssl_private_key_result_t ssl_private_key_sign_complete(
455     SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out);
456 
457 enum ssl_private_key_result_t ssl_private_key_decrypt(
458     SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
459     const uint8_t *in, size_t in_len);
460 
461 enum ssl_private_key_result_t ssl_private_key_decrypt_complete(
462     SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out);
463 
464 
465 /* Custom extensions */
466 
467 /* ssl_custom_extension (a.k.a. SSL_CUSTOM_EXTENSION) is a structure that
468  * contains information about custom-extension callbacks. */
469 struct ssl_custom_extension {
470   SSL_custom_ext_add_cb add_callback;
471   void *add_arg;
472   SSL_custom_ext_free_cb free_callback;
473   SSL_custom_ext_parse_cb parse_callback;
474   void *parse_arg;
475   uint16_t value;
476 };
477 
478 void SSL_CUSTOM_EXTENSION_free(SSL_CUSTOM_EXTENSION *custom_extension);
479 
480 int custom_ext_add_clienthello(SSL *ssl, CBB *extensions);
481 int custom_ext_parse_serverhello(SSL *ssl, int *out_alert, uint16_t value,
482                                  const CBS *extension);
483 int custom_ext_parse_clienthello(SSL *ssl, int *out_alert, uint16_t value,
484                                  const CBS *extension);
485 int custom_ext_add_serverhello(SSL *ssl, CBB *extensions);
486 
487 
488 /* Handshake hash.
489  *
490  * The TLS handshake maintains a transcript of all handshake messages. At
491  * various points in the protocol, this is either a handshake buffer, a rolling
492  * hash (selected by cipher suite) or both. */
493 
494 /* ssl3_init_handshake_buffer initializes the handshake buffer and resets the
495  * handshake hash. It returns one success and zero on failure. */
496 int ssl3_init_handshake_buffer(SSL *ssl);
497 
498 /* ssl3_init_handshake_hash initializes the handshake hash based on the pending
499  * cipher and the contents of the handshake buffer. Subsequent calls to
500  * |ssl3_update_handshake_hash| will update the rolling hash. It returns one on
501  * success and zero on failure. It is an error to call this function after the
502  * handshake buffer is released. */
503 int ssl3_init_handshake_hash(SSL *ssl);
504 
505 /* ssl3_free_handshake_buffer releases the handshake buffer. Subsequent calls
506  * to |ssl3_update_handshake_hash| will not update the handshake buffer. */
507 void ssl3_free_handshake_buffer(SSL *ssl);
508 
509 /* ssl3_free_handshake_hash releases the handshake hash. */
510 void ssl3_free_handshake_hash(SSL *ssl);
511 
512 /* ssl3_update_handshake_hash adds |in| to the handshake buffer and handshake
513  * hash, whichever is enabled. It returns one on success and zero on failure. */
514 int ssl3_update_handshake_hash(SSL *ssl, const uint8_t *in, size_t in_len);
515 
516 
517 /* ECDH curves. */
518 
519 #define SSL_CURVE_SECP256R1 23
520 #define SSL_CURVE_SECP384R1 24
521 #define SSL_CURVE_SECP521R1 25
522 #define SSL_CURVE_ECDH_X25519 29
523 
524 /* An SSL_ECDH_METHOD is an implementation of ECDH-like key exchanges for
525  * TLS. */
526 struct ssl_ecdh_method_st {
527   int nid;
528   uint16_t curve_id;
529   const char name[8];
530 
531   /* cleanup releases state in |ctx|. */
532   void (*cleanup)(SSL_ECDH_CTX *ctx);
533 
534   /* generate_keypair generates a keypair and writes the public value to
535    * |out_public_key|. It returns one on success and zero on error. */
536   int (*generate_keypair)(SSL_ECDH_CTX *ctx, CBB *out_public_key);
537 
538   /* compute_secret performs a key exchange against |peer_key| and, on
539    * success, returns one and sets |*out_secret| and |*out_secret_len| to
540    * a newly-allocated buffer containing the shared secret. The caller must
541    * release this buffer with |OPENSSL_free|. Otherwise, it returns zero and
542    * sets |*out_alert| to an alert to send to the peer. */
543   int (*compute_secret)(SSL_ECDH_CTX *ctx, uint8_t **out_secret,
544                         size_t *out_secret_len, uint8_t *out_alert,
545                         const uint8_t *peer_key, size_t peer_key_len);
546 } /* SSL_ECDH_METHOD */;
547 
548 /* ssl_nid_to_curve_id looks up the curve corresponding to |nid|. On success, it
549  * sets |*out_curve_id| to the curve ID and returns one. Otherwise, it returns
550  * zero. */
551 int ssl_nid_to_curve_id(uint16_t *out_curve_id, int nid);
552 
553 /* SSL_ECDH_CTX_init sets up |ctx| for use with curve |curve_id|. It returns one
554  * on success and zero on error. */
555 int SSL_ECDH_CTX_init(SSL_ECDH_CTX *ctx, uint16_t curve_id);
556 
557 /* SSL_ECDH_CTX_init_for_dhe sets up |ctx| for use with legacy DHE-based ciphers
558  * where the server specifies a group. It takes ownership of |params|. */
559 void SSL_ECDH_CTX_init_for_dhe(SSL_ECDH_CTX *ctx, DH *params);
560 
561 /* SSL_ECDH_CTX_cleanup releases memory associated with |ctx|. It is legal to
562  * call it in the zero state. */
563 void SSL_ECDH_CTX_cleanup(SSL_ECDH_CTX *ctx);
564 
565 /* The following functions call the corresponding method of
566  * |SSL_ECDH_METHOD|. */
567 int SSL_ECDH_CTX_generate_keypair(SSL_ECDH_CTX *ctx, CBB *out_public_key);
568 int SSL_ECDH_CTX_compute_secret(SSL_ECDH_CTX *ctx, uint8_t **out_secret,
569                                 size_t *out_secret_len, uint8_t *out_alert,
570                                 const uint8_t *peer_key, size_t peer_key_len);
571 
572 
573 /* Transport buffers. */
574 
575 /* ssl_read_buffer returns a pointer to contents of the read buffer. */
576 uint8_t *ssl_read_buffer(SSL *ssl);
577 
578 /* ssl_read_buffer_len returns the length of the read buffer. */
579 size_t ssl_read_buffer_len(const SSL *ssl);
580 
581 /* ssl_read_buffer_extend_to extends the read buffer to the desired length. For
582  * TLS, it reads to the end of the buffer until the buffer is |len| bytes
583  * long. For DTLS, it reads a new packet and ignores |len|. It returns one on
584  * success, zero on EOF, and a negative number on error.
585  *
586  * It is an error to call |ssl_read_buffer_extend_to| in DTLS when the buffer is
587  * non-empty. */
588 int ssl_read_buffer_extend_to(SSL *ssl, size_t len);
589 
590 /* ssl_read_buffer_consume consumes |len| bytes from the read buffer. It
591  * advances the data pointer and decrements the length. The memory consumed will
592  * remain valid until the next call to |ssl_read_buffer_extend| or it is
593  * discarded with |ssl_read_buffer_discard|. */
594 void ssl_read_buffer_consume(SSL *ssl, size_t len);
595 
596 /* ssl_read_buffer_discard discards the consumed bytes from the read buffer. If
597  * the buffer is now empty, it releases memory used by it. */
598 void ssl_read_buffer_discard(SSL *ssl);
599 
600 /* ssl_read_buffer_clear releases all memory associated with the read buffer and
601  * zero-initializes it. */
602 void ssl_read_buffer_clear(SSL *ssl);
603 
604 /* ssl_write_buffer_is_pending returns one if the write buffer has pending data
605  * and zero if is empty. */
606 int ssl_write_buffer_is_pending(const SSL *ssl);
607 
608 /* ssl_write_buffer_init initializes the write buffer. On success, it sets
609  * |*out_ptr| to the start of the write buffer with space for up to |max_len|
610  * bytes. It returns one on success and zero on failure. Call
611  * |ssl_write_buffer_set_len| to complete initialization. */
612 int ssl_write_buffer_init(SSL *ssl, uint8_t **out_ptr, size_t max_len);
613 
614 /* ssl_write_buffer_set_len is called after |ssl_write_buffer_init| to complete
615  * initialization after |len| bytes are written to the buffer. */
616 void ssl_write_buffer_set_len(SSL *ssl, size_t len);
617 
618 /* ssl_write_buffer_flush flushes the write buffer to the transport. It returns
619  * one on success and <= 0 on error. For DTLS, whether or not the write
620  * succeeds, the write buffer will be cleared. */
621 int ssl_write_buffer_flush(SSL *ssl);
622 
623 /* ssl_write_buffer_clear releases all memory associated with the write buffer
624  * and zero-initializes it. */
625 void ssl_write_buffer_clear(SSL *ssl);
626 
627 
628 /* Underdocumented functions.
629  *
630  * Functions below here haven't been touched up and may be underdocumented. */
631 
632 #define c2l(c, l)                                                            \
633   (l = ((unsigned long)(*((c)++))), l |= (((unsigned long)(*((c)++))) << 8), \
634    l |= (((unsigned long)(*((c)++))) << 16),                                 \
635    l |= (((unsigned long)(*((c)++))) << 24))
636 
637 /* NOTE - c is not incremented as per c2l */
638 #define c2ln(c, l1, l2, n)                       \
639   {                                              \
640     c += n;                                      \
641     l1 = l2 = 0;                                 \
642     switch (n) {                                 \
643       case 8:                                    \
644         l2 = ((unsigned long)(*(--(c)))) << 24;  \
645       case 7:                                    \
646         l2 |= ((unsigned long)(*(--(c)))) << 16; \
647       case 6:                                    \
648         l2 |= ((unsigned long)(*(--(c)))) << 8;  \
649       case 5:                                    \
650         l2 |= ((unsigned long)(*(--(c))));       \
651       case 4:                                    \
652         l1 = ((unsigned long)(*(--(c)))) << 24;  \
653       case 3:                                    \
654         l1 |= ((unsigned long)(*(--(c)))) << 16; \
655       case 2:                                    \
656         l1 |= ((unsigned long)(*(--(c)))) << 8;  \
657       case 1:                                    \
658         l1 |= ((unsigned long)(*(--(c))));       \
659     }                                            \
660   }
661 
662 #define l2c(l, c)                            \
663   (*((c)++) = (uint8_t)(((l)) & 0xff),       \
664    *((c)++) = (uint8_t)(((l) >> 8) & 0xff),  \
665    *((c)++) = (uint8_t)(((l) >> 16) & 0xff), \
666    *((c)++) = (uint8_t)(((l) >> 24) & 0xff))
667 
668 #define n2l(c, l)                          \
669   (l = ((unsigned long)(*((c)++))) << 24,  \
670    l |= ((unsigned long)(*((c)++))) << 16, \
671    l |= ((unsigned long)(*((c)++))) << 8, l |= ((unsigned long)(*((c)++))))
672 
673 #define l2n(l, c)                            \
674   (*((c)++) = (uint8_t)(((l) >> 24) & 0xff), \
675    *((c)++) = (uint8_t)(((l) >> 16) & 0xff), \
676    *((c)++) = (uint8_t)(((l) >> 8) & 0xff),  \
677    *((c)++) = (uint8_t)(((l)) & 0xff))
678 
679 #define l2n8(l, c)                           \
680   (*((c)++) = (uint8_t)(((l) >> 56) & 0xff), \
681    *((c)++) = (uint8_t)(((l) >> 48) & 0xff), \
682    *((c)++) = (uint8_t)(((l) >> 40) & 0xff), \
683    *((c)++) = (uint8_t)(((l) >> 32) & 0xff), \
684    *((c)++) = (uint8_t)(((l) >> 24) & 0xff), \
685    *((c)++) = (uint8_t)(((l) >> 16) & 0xff), \
686    *((c)++) = (uint8_t)(((l) >> 8) & 0xff),  \
687    *((c)++) = (uint8_t)(((l)) & 0xff))
688 
689 /* NOTE - c is not incremented as per l2c */
690 #define l2cn(l1, l2, c, n)                               \
691   {                                                      \
692     c += n;                                              \
693     switch (n) {                                         \
694       case 8:                                            \
695         *(--(c)) = (uint8_t)(((l2) >> 24) & 0xff); \
696       case 7:                                            \
697         *(--(c)) = (uint8_t)(((l2) >> 16) & 0xff); \
698       case 6:                                            \
699         *(--(c)) = (uint8_t)(((l2) >> 8) & 0xff);  \
700       case 5:                                            \
701         *(--(c)) = (uint8_t)(((l2)) & 0xff);       \
702       case 4:                                            \
703         *(--(c)) = (uint8_t)(((l1) >> 24) & 0xff); \
704       case 3:                                            \
705         *(--(c)) = (uint8_t)(((l1) >> 16) & 0xff); \
706       case 2:                                            \
707         *(--(c)) = (uint8_t)(((l1) >> 8) & 0xff);  \
708       case 1:                                            \
709         *(--(c)) = (uint8_t)(((l1)) & 0xff);       \
710     }                                                    \
711   }
712 
713 #define n2s(c, s) \
714   ((s = (((unsigned int)(c[0])) << 8) | (((unsigned int)(c[1])))), c += 2)
715 
716 #define s2n(s, c)                              \
717   ((c[0] = (uint8_t)(((s) >> 8) & 0xff), \
718     c[1] = (uint8_t)(((s)) & 0xff)),     \
719    c += 2)
720 
721 #define n2l3(c, l)                                                         \
722   ((l = (((unsigned long)(c[0])) << 16) | (((unsigned long)(c[1])) << 8) | \
723         (((unsigned long)(c[2])))),                                        \
724    c += 3)
725 
726 #define l2n3(l, c)                              \
727   ((c[0] = (uint8_t)(((l) >> 16) & 0xff), \
728     c[1] = (uint8_t)(((l) >> 8) & 0xff),  \
729     c[2] = (uint8_t)(((l)) & 0xff)),      \
730    c += 3)
731 
732 /* LOCAL STUFF */
733 
734 #define TLSEXT_CHANNEL_ID_SIZE 128
735 
736 /* Check if an SSL structure is using DTLS */
737 #define SSL_IS_DTLS(ssl) (ssl->method->is_dtls)
738 /* See if we need explicit IV */
739 #define SSL_USE_EXPLICIT_IV(ssl) \
740   (ssl->enc_method->enc_flags & SSL_ENC_FLAG_EXPLICIT_IV)
741 /* See if we use signature algorithms extension and signature algorithm before
742  * signatures. */
743 #define SSL_USE_SIGALGS(ssl) (ssl->enc_method->enc_flags & SSL_ENC_FLAG_SIGALGS)
744 
745 /* From RFC4492, used in encoding the curve type in ECParameters */
746 #define NAMED_CURVE_TYPE 3
747 
748 enum ssl_hash_message_t {
749   ssl_dont_hash_message,
750   ssl_hash_message,
751 };
752 
753 /* Structure containing decoded values of signature algorithms extension */
754 typedef struct tls_sigalgs_st {
755   uint8_t rsign;
756   uint8_t rhash;
757 } TLS_SIGALGS;
758 
759 typedef struct cert_st {
760   X509 *x509;
761   EVP_PKEY *privatekey;
762   /* Chain for this certificate */
763   STACK_OF(X509) *chain;
764 
765   /* key_method, if non-NULL, is a set of callbacks to call for private key
766    * operations. */
767   const SSL_PRIVATE_KEY_METHOD *key_method;
768 
769   /* For clients the following masks are of *disabled* key and auth algorithms
770    * based on the current configuration.
771    *
772    * TODO(davidben): Remove these. They get checked twice: when sending the
773    * ClientHello and when processing the ServerHello. */
774   uint32_t mask_k;
775   uint32_t mask_a;
776 
777   DH *dh_tmp;
778   DH *(*dh_tmp_cb)(SSL *ssl, int is_export, int keysize);
779 
780   /* peer_sigalgs are the algorithm/hash pairs that the peer supports. These
781    * are taken from the contents of signature algorithms extension for a server
782    * or from the CertificateRequest for a client. */
783   TLS_SIGALGS *peer_sigalgs;
784   /* peer_sigalgslen is the number of entries in |peer_sigalgs|. */
785   size_t peer_sigalgslen;
786 
787   /* digest_nids, if non-NULL, is the set of digests supported by |privatekey|
788    * in decreasing order of preference. */
789   int *digest_nids;
790   size_t num_digest_nids;
791 
792   /* Certificate setup callback: if set is called whenever a
793    * certificate may be required (client or server). the callback
794    * can then examine any appropriate parameters and setup any
795    * certificates required. This allows advanced applications
796    * to select certificates on the fly: for example based on
797    * supported signature algorithms or curves. */
798   int (*cert_cb)(SSL *ssl, void *arg);
799   void *cert_cb_arg;
800 } CERT;
801 
802 /* SSL_METHOD is a compatibility structure to support the legacy version-locked
803  * methods. */
804 struct ssl_method_st {
805   /* version, if non-zero, is the only protocol version acceptable to an
806    * SSL_CTX initialized from this method. */
807   uint16_t version;
808   /* method is the underlying SSL_PROTOCOL_METHOD that initializes the
809    * SSL_CTX. */
810   const SSL_PROTOCOL_METHOD *method;
811 };
812 
813 /* Used to hold functions for SSLv2 or SSLv3/TLSv1 functions */
814 struct ssl_protocol_method_st {
815   /* is_dtls is one if the protocol is DTLS and zero otherwise. */
816   char is_dtls;
817   int (*ssl_new)(SSL *ssl);
818   void (*ssl_free)(SSL *ssl);
819   int (*ssl_accept)(SSL *ssl);
820   int (*ssl_connect)(SSL *ssl);
821   long (*ssl_get_message)(SSL *ssl, int header_state, int body_state,
822                           int msg_type, long max,
823                           enum ssl_hash_message_t hash_message, int *ok);
824   int (*ssl_read_app_data)(SSL *ssl, uint8_t *buf, int len, int peek);
825   int (*ssl_read_change_cipher_spec)(SSL *ssl);
826   void (*ssl_read_close_notify)(SSL *ssl);
827   int (*ssl_write_app_data)(SSL *ssl, const void *buf_, int len);
828   int (*ssl_dispatch_alert)(SSL *ssl);
829   /* supports_cipher returns one if |cipher| is supported by this protocol and
830    * zero otherwise. */
831   int (*supports_cipher)(const SSL_CIPHER *cipher);
832   /* Handshake header length */
833   unsigned int hhlen;
834   /* Set the handshake header */
835   int (*set_handshake_header)(SSL *ssl, int type, unsigned long len);
836   /* Write out handshake message */
837   int (*do_write)(SSL *ssl);
838 };
839 
840 /* This is for the SSLv3/TLSv1.0 differences in crypto/hash stuff It is a bit
841  * of a mess of functions, but hell, think of it as an opaque structure. */
842 struct ssl3_enc_method {
843   int (*prf)(SSL *, uint8_t *, size_t, const uint8_t *, size_t, const char *,
844              size_t, const uint8_t *, size_t, const uint8_t *, size_t);
845   int (*setup_key_block)(SSL *);
846   int (*generate_master_secret)(SSL *, uint8_t *, const uint8_t *, size_t);
847   int (*change_cipher_state)(SSL *, int);
848   int (*final_finish_mac)(SSL *, const char *, int, uint8_t *);
849   int (*cert_verify_mac)(SSL *, int, uint8_t *);
850   const char *client_finished_label;
851   int client_finished_label_len;
852   const char *server_finished_label;
853   int server_finished_label_len;
854   int (*alert_value)(int);
855   int (*export_keying_material)(SSL *, uint8_t *, size_t, const char *, size_t,
856                                 const uint8_t *, size_t, int use_context);
857   /* Various flags indicating protocol version requirements */
858   unsigned int enc_flags;
859 };
860 
861 #define SSL_HM_HEADER_LENGTH(ssl) ssl->method->hhlen
862 #define ssl_handshake_start(ssl) \
863   (((uint8_t *)ssl->init_buf->data) + ssl->method->hhlen)
864 #define ssl_set_handshake_header(ssl, htype, len) \
865   ssl->method->set_handshake_header(ssl, htype, len)
866 #define ssl_do_write(ssl) ssl->method->do_write(ssl)
867 
868 /* Values for enc_flags */
869 
870 /* Uses explicit IV for CBC mode */
871 #define SSL_ENC_FLAG_EXPLICIT_IV 0x1
872 /* Uses signature algorithms extension */
873 #define SSL_ENC_FLAG_SIGALGS 0x2
874 /* Uses SHA256 default PRF */
875 #define SSL_ENC_FLAG_SHA256_PRF 0x4
876 
877 /* lengths of messages */
878 #define DTLS1_COOKIE_LENGTH 256
879 
880 #define DTLS1_RT_HEADER_LENGTH 13
881 
882 #define DTLS1_HM_HEADER_LENGTH 12
883 
884 #define DTLS1_CCS_HEADER_LENGTH 1
885 
886 #define DTLS1_AL_HEADER_LENGTH 2
887 
888 /* TODO(davidben): This structure is used for both incoming messages and
889  * outgoing messages. |is_ccs| and |epoch| are only used in the latter and
890  * should be moved elsewhere. */
891 struct hm_header_st {
892   uint8_t type;
893   uint32_t msg_len;
894   uint16_t seq;
895   uint32_t frag_off;
896   uint32_t frag_len;
897   int is_ccs;
898   /* epoch, for buffered outgoing messages, is the epoch the message was
899    * originally sent in. */
900   uint16_t epoch;
901 };
902 
903 /* TODO(davidben): This structure is used for both incoming messages and
904  * outgoing messages. |fragment| and |reassembly| are only used in the former
905  * and should be moved elsewhere. */
906 typedef struct hm_fragment_st {
907   struct hm_header_st msg_header;
908   uint8_t *fragment;
909   uint8_t *reassembly;
910 } hm_fragment;
911 
912 typedef struct dtls1_state_st {
913   /* send_cookie is true if we are resending the ClientHello
914    * with a cookie from a HelloVerifyRequest. */
915   unsigned int send_cookie;
916 
917   uint8_t cookie[DTLS1_COOKIE_LENGTH];
918   size_t cookie_len;
919 
920   /* The current data and handshake epoch.  This is initially undefined, and
921    * starts at zero once the initial handshake is completed. */
922   uint16_t r_epoch;
923   uint16_t w_epoch;
924 
925   /* records being received in the current epoch */
926   DTLS1_BITMAP bitmap;
927 
928   /* handshake message numbers.
929    * TODO(davidben): It doesn't make much sense to store both of these. Only
930    * store one. */
931   uint16_t handshake_write_seq;
932   uint16_t next_handshake_write_seq;
933 
934   uint16_t handshake_read_seq;
935 
936   /* save last sequence number for retransmissions */
937   uint8_t last_write_sequence[8];
938 
939   /* buffered_messages is a priority queue of incoming handshake messages that
940    * have yet to be processed.
941    *
942    * TODO(davidben): This data structure may as well be a ring buffer of fixed
943    * size. */
944   pqueue buffered_messages;
945 
946   /* send_messages is a priority queue of outgoing handshake messages sent in
947    * the most recent handshake flight.
948    *
949    * TODO(davidben): This data structure may as well be a STACK_OF(T). */
950   pqueue sent_messages;
951 
952   unsigned int mtu; /* max DTLS packet size */
953 
954   struct hm_header_st w_msg_hdr;
955 
956   /* num_timeouts is the number of times the retransmit timer has fired since
957    * the last time it was reset. */
958   unsigned int num_timeouts;
959 
960   /* Indicates when the last handshake msg or heartbeat sent will
961    * timeout. */
962   struct timeval next_timeout;
963 
964   /* Timeout duration */
965   unsigned short timeout_duration;
966 } DTLS1_STATE;
967 
968 extern const SSL3_ENC_METHOD TLSv1_enc_data;
969 extern const SSL3_ENC_METHOD TLSv1_1_enc_data;
970 extern const SSL3_ENC_METHOD TLSv1_2_enc_data;
971 extern const SSL3_ENC_METHOD SSLv3_enc_data;
972 extern const SRTP_PROTECTION_PROFILE kSRTPProfiles[];
973 
974 void ssl_clear_cipher_ctx(SSL *ssl);
975 int ssl_clear_bad_session(SSL *ssl);
976 CERT *ssl_cert_new(void);
977 CERT *ssl_cert_dup(CERT *cert);
978 void ssl_cert_clear_certs(CERT *c);
979 void ssl_cert_free(CERT *c);
980 int ssl_get_new_session(SSL *ssl, int is_server);
981 
982 enum ssl_session_result_t {
983   ssl_session_success,
984   ssl_session_error,
985   ssl_session_retry,
986 };
987 
988 /* ssl_get_prev_session looks up the previous session based on |ctx|. On
989  * success, it sets |*out_session| to the session or NULL if none was found. It
990  * sets |*out_send_ticket| to whether a ticket should be sent at the end of the
991  * handshake. If the session could not be looked up synchronously, it returns
992  * |ssl_session_retry| and should be called again. Otherwise, it returns
993  * |ssl_session_error|.  */
994 enum ssl_session_result_t ssl_get_prev_session(
995     SSL *ssl, SSL_SESSION **out_session, int *out_send_ticket,
996     const struct ssl_early_callback_ctx *ctx);
997 
998 STACK_OF(SSL_CIPHER) *ssl_bytes_to_cipher_list(SSL *ssl, const CBS *cbs);
999 void ssl_cipher_preference_list_free(
1000     struct ssl_cipher_preference_list_st *cipher_list);
1001 struct ssl_cipher_preference_list_st *ssl_get_cipher_preferences(SSL *ssl);
1002 
1003 int ssl_cert_set0_chain(CERT *cert, STACK_OF(X509) *chain);
1004 int ssl_cert_set1_chain(CERT *cert, STACK_OF(X509) *chain);
1005 int ssl_cert_add0_chain_cert(CERT *cert, X509 *x509);
1006 int ssl_cert_add1_chain_cert(CERT *cert, X509 *x509);
1007 void ssl_cert_set_cert_cb(CERT *cert,
1008                           int (*cb)(SSL *ssl, void *arg), void *arg);
1009 
1010 int ssl_verify_cert_chain(SSL *ssl, STACK_OF(X509) *cert_chain);
1011 int ssl_add_cert_chain(SSL *ssl, unsigned long *l);
1012 void ssl_update_cache(SSL *ssl, int mode);
1013 
1014 /* ssl_get_compatible_server_ciphers determines the key exchange and
1015  * authentication cipher suite masks compatible with the server configuration
1016  * and current ClientHello parameters of |ssl|. It sets |*out_mask_k| to the key
1017  * exchange mask and |*out_mask_a| to the authentication mask. */
1018 void ssl_get_compatible_server_ciphers(SSL *ssl, uint32_t *out_mask_k,
1019                                        uint32_t *out_mask_a);
1020 
1021 STACK_OF(SSL_CIPHER) *ssl_get_ciphers_by_id(SSL *ssl);
1022 int ssl_verify_alarm_type(long type);
1023 
1024 /* ssl_fill_hello_random fills a client_random or server_random field of length
1025  * |len|. It returns one on success and zero on failure. */
1026 int ssl_fill_hello_random(uint8_t *out, size_t len, int is_server);
1027 
1028 int ssl3_send_server_certificate(SSL *ssl);
1029 int ssl3_send_new_session_ticket(SSL *ssl);
1030 int ssl3_send_certificate_status(SSL *ssl);
1031 int ssl3_get_finished(SSL *ssl, int state_a, int state_b);
1032 int ssl3_send_change_cipher_spec(SSL *ssl, int state_a, int state_b);
1033 int ssl3_prf(SSL *ssl, uint8_t *out, size_t out_len, const uint8_t *secret,
1034              size_t secret_len, const char *label, size_t label_len,
1035              const uint8_t *seed1, size_t seed1_len,
1036              const uint8_t *seed2, size_t seed2_len);
1037 void ssl3_cleanup_key_block(SSL *ssl);
1038 int ssl3_do_write(SSL *ssl, int type);
1039 int ssl3_send_alert(SSL *ssl, int level, int desc);
1040 int ssl3_get_req_cert_type(SSL *ssl, uint8_t *p);
1041 long ssl3_get_message(SSL *ssl, int header_state, int body_state, int msg_type,
1042                       long max, enum ssl_hash_message_t hash_message, int *ok);
1043 
1044 /* ssl3_hash_current_message incorporates the current handshake message into the
1045  * handshake hash. It returns one on success and zero on allocation failure. */
1046 int ssl3_hash_current_message(SSL *ssl);
1047 
1048 /* ssl3_cert_verify_hash writes the CertificateVerify hash into the bytes
1049  * pointed to by |out| and writes the number of bytes to |*out_len|. |out| must
1050  * have room for EVP_MAX_MD_SIZE bytes. For TLS 1.2 and up, |*out_md| is used
1051  * for the hash function, otherwise the hash function depends on |pkey_type|
1052  * and is written to |*out_md|. It returns one on success and zero on
1053  * failure. */
1054 int ssl3_cert_verify_hash(SSL *ssl, uint8_t *out, size_t *out_len,
1055                           const EVP_MD **out_md, int pkey_type);
1056 
1057 int ssl3_send_finished(SSL *ssl, int a, int b, const char *sender, int slen);
1058 int ssl3_supports_cipher(const SSL_CIPHER *cipher);
1059 int ssl3_dispatch_alert(SSL *ssl);
1060 int ssl3_read_app_data(SSL *ssl, uint8_t *buf, int len, int peek);
1061 int ssl3_read_change_cipher_spec(SSL *ssl);
1062 void ssl3_read_close_notify(SSL *ssl);
1063 int ssl3_read_bytes(SSL *ssl, int type, uint8_t *buf, int len, int peek);
1064 int ssl3_write_app_data(SSL *ssl, const void *buf, int len);
1065 int ssl3_write_bytes(SSL *ssl, int type, const void *buf, int len);
1066 int ssl3_final_finish_mac(SSL *ssl, const char *sender, int slen, uint8_t *p);
1067 int ssl3_cert_verify_mac(SSL *ssl, int md_nid, uint8_t *p);
1068 int ssl3_output_cert_chain(SSL *ssl);
1069 const SSL_CIPHER *ssl3_choose_cipher(
1070     SSL *ssl, STACK_OF(SSL_CIPHER) *clnt,
1071     struct ssl_cipher_preference_list_st *srvr);
1072 
1073 int ssl3_new(SSL *ssl);
1074 void ssl3_free(SSL *ssl);
1075 int ssl3_accept(SSL *ssl);
1076 int ssl3_connect(SSL *ssl);
1077 
1078 /* ssl3_record_sequence_update increments the sequence number in |seq|. It
1079  * returns one on success and zero on wraparound. */
1080 int ssl3_record_sequence_update(uint8_t *seq, size_t seq_len);
1081 
1082 int ssl3_do_change_cipher_spec(SSL *ssl);
1083 
1084 int ssl3_set_handshake_header(SSL *ssl, int htype, unsigned long len);
1085 int ssl3_handshake_write(SSL *ssl);
1086 
1087 int dtls1_do_handshake_write(SSL *ssl, enum dtls1_use_epoch_t use_epoch);
1088 int dtls1_read_app_data(SSL *ssl, uint8_t *buf, int len, int peek);
1089 int dtls1_read_change_cipher_spec(SSL *ssl);
1090 void dtls1_read_close_notify(SSL *ssl);
1091 int dtls1_read_bytes(SSL *ssl, int type, uint8_t *buf, int len, int peek);
1092 void dtls1_set_message_header(SSL *ssl, uint8_t mt, unsigned long len,
1093                               unsigned short seq_num, unsigned long frag_off,
1094                               unsigned long frag_len);
1095 
1096 int dtls1_write_app_data(SSL *ssl, const void *buf, int len);
1097 int dtls1_write_bytes(SSL *ssl, int type, const void *buf, int len,
1098                       enum dtls1_use_epoch_t use_epoch);
1099 
1100 int dtls1_send_change_cipher_spec(SSL *ssl, int a, int b);
1101 int dtls1_send_finished(SSL *ssl, int a, int b, const char *sender, int slen);
1102 int dtls1_read_failed(SSL *ssl, int code);
1103 int dtls1_buffer_message(SSL *ssl);
1104 int dtls1_retransmit_buffered_messages(SSL *ssl);
1105 void dtls1_clear_record_buffer(SSL *ssl);
1106 void dtls1_get_message_header(uint8_t *data, struct hm_header_st *msg_hdr);
1107 int dtls1_check_timeout_num(SSL *ssl);
1108 int dtls1_set_handshake_header(SSL *ssl, int type, unsigned long len);
1109 int dtls1_handshake_write(SSL *ssl);
1110 
1111 int dtls1_supports_cipher(const SSL_CIPHER *cipher);
1112 void dtls1_start_timer(SSL *ssl);
1113 void dtls1_stop_timer(SSL *ssl);
1114 int dtls1_is_timer_expired(SSL *ssl);
1115 void dtls1_double_timeout(SSL *ssl);
1116 unsigned int dtls1_min_mtu(void);
1117 void dtls1_hm_fragment_free(hm_fragment *frag);
1118 
1119 /* some client-only functions */
1120 int ssl3_send_client_hello(SSL *ssl);
1121 int ssl3_get_server_hello(SSL *ssl);
1122 int ssl3_get_certificate_request(SSL *ssl);
1123 int ssl3_get_new_session_ticket(SSL *ssl);
1124 int ssl3_get_cert_status(SSL *ssl);
1125 int ssl3_get_server_done(SSL *ssl);
1126 int ssl3_send_cert_verify(SSL *ssl);
1127 int ssl3_send_client_certificate(SSL *ssl);
1128 int ssl_do_client_cert_cb(SSL *ssl, X509 **px509, EVP_PKEY **ppkey);
1129 int ssl3_send_client_key_exchange(SSL *ssl);
1130 int ssl3_get_server_key_exchange(SSL *ssl);
1131 int ssl3_get_server_certificate(SSL *ssl);
1132 int ssl3_send_next_proto(SSL *ssl);
1133 int ssl3_send_channel_id(SSL *ssl);
1134 int ssl3_verify_server_cert(SSL *ssl);
1135 
1136 /* some server-only functions */
1137 int ssl3_get_initial_bytes(SSL *ssl);
1138 int ssl3_get_v2_client_hello(SSL *ssl);
1139 int ssl3_get_client_hello(SSL *ssl);
1140 int ssl3_send_server_hello(SSL *ssl);
1141 int ssl3_send_server_key_exchange(SSL *ssl);
1142 int ssl3_send_certificate_request(SSL *ssl);
1143 int ssl3_send_server_done(SSL *ssl);
1144 int ssl3_get_client_certificate(SSL *ssl);
1145 int ssl3_get_client_key_exchange(SSL *ssl);
1146 int ssl3_get_cert_verify(SSL *ssl);
1147 int ssl3_get_next_proto(SSL *ssl);
1148 int ssl3_get_channel_id(SSL *ssl);
1149 
1150 int dtls1_new(SSL *ssl);
1151 int dtls1_accept(SSL *ssl);
1152 int dtls1_connect(SSL *ssl);
1153 void dtls1_free(SSL *ssl);
1154 
1155 long dtls1_get_message(SSL *ssl, int st1, int stn, int mt, long max,
1156                        enum ssl_hash_message_t hash_message, int *ok);
1157 int dtls1_dispatch_alert(SSL *ssl);
1158 
1159 int ssl_init_wbio_buffer(SSL *ssl, int push);
1160 void ssl_free_wbio_buffer(SSL *ssl);
1161 
1162 /* tls1_prf computes the TLS PRF function for |ssl| as described in RFC 5246,
1163  * section 5 and RFC 2246 section 5. It writes |out_len| bytes to |out|, using
1164  * |secret| as the secret and |label| as the label. |seed1| and |seed2| are
1165  * concatenated to form the seed parameter. It returns one on success and zero
1166  * on failure. */
1167 int tls1_prf(SSL *ssl, uint8_t *out, size_t out_len, const uint8_t *secret,
1168              size_t secret_len, const char *label, size_t label_len,
1169              const uint8_t *seed1, size_t seed1_len,
1170              const uint8_t *seed2, size_t seed2_len);
1171 
1172 int tls1_change_cipher_state(SSL *ssl, int which);
1173 int tls1_setup_key_block(SSL *ssl);
1174 int tls1_handshake_digest(SSL *ssl, uint8_t *out, size_t out_len);
1175 int tls1_final_finish_mac(SSL *ssl, const char *str, int slen, uint8_t *p);
1176 int tls1_cert_verify_mac(SSL *ssl, int md_nid, uint8_t *p);
1177 int tls1_generate_master_secret(SSL *ssl, uint8_t *out, const uint8_t *premaster,
1178                                 size_t premaster_len);
1179 int tls1_export_keying_material(SSL *ssl, uint8_t *out, size_t out_len,
1180                                 const char *label, size_t label_len,
1181                                 const uint8_t *context, size_t context_len,
1182                                 int use_context);
1183 int tls1_alert_code(int code);
1184 int ssl3_alert_code(int code);
1185 
1186 char ssl_early_callback_init(struct ssl_early_callback_ctx *ctx);
1187 
1188 /* tls1_check_curve_id returns one if |curve_id| is consistent with both our
1189  * and the peer's curve preferences. Note: if called as the client, only our
1190  * preferences are checked; the peer (the server) does not send preferences. */
1191 int tls1_check_curve_id(SSL *ssl, uint16_t curve_id);
1192 
1193 /* tls1_get_shared_curve sets |*out_curve_id| to the first preferred shared
1194  * curve between client and server preferences and returns one. If none may be
1195  * found, it returns zero. */
1196 int tls1_get_shared_curve(SSL *ssl, uint16_t *out_curve_id);
1197 
1198 /* tls1_set_curves converts the array of |ncurves| NIDs pointed to by |curves|
1199  * into a newly allocated array of TLS curve IDs. On success, the function
1200  * returns one and writes the array to |*out_curve_ids| and its size to
1201  * |*out_curve_ids_len|. Otherwise, it returns zero. */
1202 int tls1_set_curves(uint16_t **out_curve_ids, size_t *out_curve_ids_len,
1203                     const int *curves, size_t ncurves);
1204 
1205 /* tls1_check_ec_cert returns one if |x| is an ECC certificate with curve and
1206  * point format compatible with the client's preferences. Otherwise it returns
1207  * zero. */
1208 int tls1_check_ec_cert(SSL *ssl, X509 *x);
1209 
1210 /* ssl_add_clienthello_tlsext writes ClientHello extensions to |out|. It
1211  * returns one on success and zero on failure. The |header_len| argument is the
1212  * length of the ClientHello written so far and is used to compute the padding
1213  * length. (It does not include the record header.) */
1214 int ssl_add_clienthello_tlsext(SSL *ssl, CBB *out, size_t header_len);
1215 
1216 int ssl_add_serverhello_tlsext(SSL *ssl, CBB *out);
1217 int ssl_parse_clienthello_tlsext(SSL *ssl, CBS *cbs);
1218 int ssl_parse_serverhello_tlsext(SSL *ssl, CBS *cbs);
1219 
1220 #define tlsext_tick_md EVP_sha256
1221 
1222 /* tls_process_ticket processes the session ticket extension. On success, it
1223  * sets |*out_session| to the decrypted session or NULL if the ticket was
1224  * rejected. It sets |*out_send_ticket| to whether a new ticket should be sent
1225  * at the end of the handshake. It returns one on success and zero on fatal
1226  * error. */
1227 int tls_process_ticket(SSL *ssl, SSL_SESSION **out_session,
1228                        int *out_send_ticket, const uint8_t *ticket,
1229                        size_t ticket_len, const uint8_t *session_id,
1230                        size_t session_id_len);
1231 
1232 /* tls12_add_sigandhash assembles the SignatureAndHashAlgorithm corresponding to
1233  * |ssl|'s private key and |md|. The two-byte value is written to |out|. It
1234  * returns one on success and zero on failure. */
1235 int tls12_add_sigandhash(SSL *ssl, CBB *out, const EVP_MD *md);
1236 
1237 int tls12_get_sigid(int pkey_type);
1238 const EVP_MD *tls12_get_hash(uint8_t hash_alg);
1239 
1240 /* tls1_channel_id_hash computes the hash to be signed by Channel ID and writes
1241  * it to |out|, which must contain at least |EVP_MAX_MD_SIZE| bytes. It returns
1242  * one on success and zero on failure. */
1243 int tls1_channel_id_hash(SSL *ssl, uint8_t *out, size_t *out_len);
1244 
1245 int tls1_record_handshake_hashes_for_channel_id(SSL *ssl);
1246 
1247 /* ssl_log_rsa_client_key_exchange logs |premaster|, if logging is enabled for
1248  * |ssl|. It returns one on success and zero on failure. The entry is identified
1249  * by the first 8 bytes of |encrypted_premaster|. */
1250 int ssl_log_rsa_client_key_exchange(const SSL *ssl,
1251                                     const uint8_t *encrypted_premaster,
1252                                     size_t encrypted_premaster_len,
1253                                     const uint8_t *premaster,
1254                                     size_t premaster_len);
1255 
1256 /* ssl_log_master_secret logs |master|, if logging is enabled for |ssl|. It
1257  * returns one on success and zero on failure. The entry is identified by
1258  * |client_random|. */
1259 int ssl_log_master_secret(const SSL *ssl, const uint8_t *client_random,
1260                           size_t client_random_len, const uint8_t *master,
1261                           size_t master_len);
1262 
1263 /* ssl3_can_false_start returns one if |ssl| is allowed to False Start and zero
1264  * otherwise. */
1265 int ssl3_can_false_start(const SSL *ssl);
1266 
1267 /* ssl3_get_enc_method returns the SSL3_ENC_METHOD corresponding to
1268  * |version|. */
1269 const SSL3_ENC_METHOD *ssl3_get_enc_method(uint16_t version);
1270 
1271 /* ssl3_get_max_server_version returns the maximum SSL/TLS version number
1272  * supported by |ssl| as a server, or zero if all versions are disabled. */
1273 uint16_t ssl3_get_max_server_version(const SSL *ssl);
1274 
1275 /* ssl3_get_mutual_version selects the protocol version on |ssl| for a client
1276  * which advertises |client_version|. If no suitable version exists, it returns
1277  * zero. */
1278 uint16_t ssl3_get_mutual_version(SSL *ssl, uint16_t client_version);
1279 
1280 /* ssl3_get_max_client_version returns the maximum protocol version configured
1281  * for the client. It is guaranteed that the set of allowed versions at or below
1282  * this maximum version is contiguous. If all versions are disabled, it returns
1283  * zero. */
1284 uint16_t ssl3_get_max_client_version(SSL *ssl);
1285 
1286 /* ssl3_is_version_enabled returns one if |version| is an enabled protocol
1287  * version for |ssl| and zero otherwise. */
1288 int ssl3_is_version_enabled(SSL *ssl, uint16_t version);
1289 
1290 /* ssl3_version_from_wire maps |wire_version| to a protocol version. For
1291  * SSLv3/TLS, the version is returned as-is. For DTLS, the corresponding TLS
1292  * version is used. Note that this mapping is not injective but preserves
1293  * comparisons.
1294  *
1295  * TODO(davidben): To normalize some DTLS-specific code, move away from using
1296  * the wire version except at API boundaries. */
1297 uint16_t ssl3_version_from_wire(SSL *ssl, uint16_t wire_version);
1298 
1299 uint32_t ssl_get_algorithm_prf(SSL *ssl);
1300 int tls1_parse_peer_sigalgs(SSL *ssl, const CBS *sigalgs);
1301 
1302 /* tls1_choose_signing_digest returns a digest for use with |ssl|'s private key
1303  * based on the peer's preferences the digests supported. */
1304 const EVP_MD *tls1_choose_signing_digest(SSL *ssl);
1305 
1306 size_t tls12_get_psigalgs(SSL *ssl, const uint8_t **psigs);
1307 
1308 /* tls12_check_peer_sigalg checks that |hash| and |signature| are consistent
1309  * with |pkey| and |ssl|'s sent, supported signature algorithms and, if so,
1310  * writes the relevant digest into |*out_md| and returns 1. Otherwise it
1311  * returns 0 and writes an alert into |*out_alert|. */
1312 int tls12_check_peer_sigalg(SSL *ssl, const EVP_MD **out_md, int *out_alert,
1313                             uint8_t hash, uint8_t signature, EVP_PKEY *pkey);
1314 void ssl_set_client_disabled(SSL *ssl);
1315 
1316 #endif /* OPENSSL_HEADER_SSL_INTERNAL_H */
1317