2 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 #include "../ssl_locl.h"
11 #include "statem_locl.h"
13 static int final_renegotiate(SSL *s, unsigned int context, int sent,
15 static int init_server_name(SSL *s, unsigned int context);
16 static int final_server_name(SSL *s, unsigned int context, int sent,
19 static int final_ec_pt_formats(SSL *s, unsigned int context, int sent,
22 static int init_session_ticket(SSL *s, unsigned int context);
23 #ifndef OPENSSL_NO_OCSP
24 static int init_status_request(SSL *s, unsigned int context);
25 static int final_status_request(SSL *s, unsigned int context, int sent,
28 #ifndef OPENSSL_NO_NEXTPROTONEG
29 static int init_npn(SSL *s, unsigned int context);
31 static int init_alpn(SSL *s, unsigned int context);
32 static int final_alpn(SSL *s, unsigned int context, int sent, int *al);
33 static int init_sig_algs(SSL *s, unsigned int context);
34 #ifndef OPENSSL_NO_SRP
35 static int init_srp(SSL *s, unsigned int context);
37 static int init_etm(SSL *s, unsigned int context);
38 static int init_ems(SSL *s, unsigned int context);
39 static int final_ems(SSL *s, unsigned int context, int sent, int *al);
40 #ifndef OPENSSL_NO_SRTP
41 static int init_srtp(SSL *s, unsigned int context);
44 /* Structure to define a built-in extension */
45 typedef struct extensions_definition_st {
46 /* The defined type for the extension */
49 * The context that this extension applies to, e.g. what messages and
54 * Initialise extension before parsing. Always called for relevant contexts
55 * even if extension not present
57 int (*init)(SSL *s, unsigned int context);
58 /* Parse extension sent from client to server */
59 int (*parse_ctos)(SSL *s, PACKET *pkt, int *al);
60 /* Parse extension send from server to client */
61 int (*parse_stoc)(SSL *s, PACKET *pkt, int *al);
62 /* Construct extension sent from server to client */
63 int (*construct_stoc)(SSL *s, WPACKET *pkt, int *al);
64 /* Construct extension sent from client to server */
65 int (*construct_ctos)(SSL *s, WPACKET *pkt, int *al);
67 * Finalise extension after parsing. Always called where an extensions was
68 * initialised even if the extension was not present. |sent| is set to 1 if
69 * the extension was seen, or 0 otherwise.
71 int (*final)(SSL *s, unsigned int context, int sent, int *al);
72 } EXTENSION_DEFINITION;
75 * Definitions of all built-in extensions. NOTE: Changes in the number or order
76 * of these extensions should be mirrored with equivalent changes to the indexes
77 * defined in statem_locl.h.
78 * Each extension has an initialiser, a client and
79 * server side parser and a finaliser. The initialiser is called (if the
80 * extension is relevant to the given context) even if we did not see the
81 * extension in the message that we received. The parser functions are only
82 * called if we see the extension in the message. The finalisers are always
83 * called if the initialiser was called.
84 * There are also server and client side constructor functions which are always
85 * called during message construction if the extension is relevant for the
87 * The initialisation, parsing, finalisation and construction functions are
88 * always called in the order defined in this list. Some extensions may depend
89 * on others having been processed first, so the order of this list is
91 * The extension context is defined by a series of flags which specify which
92 * messages the extension is relevant to. These flags also specify whether the
93 * extension is relevant to a paricular protocol or protocol version.
95 * TODO(TLS1.3): Make sure we have a test to check the consistency of these
97 #define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL }
98 static const EXTENSION_DEFINITION ext_defs[] = {
100 TLSEXT_TYPE_renegotiate,
101 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_SSL3_ALLOWED
102 | EXT_TLS1_2_AND_BELOW_ONLY,
103 NULL, tls_parse_ctos_renegotiate, tls_parse_stoc_renegotiate,
104 tls_construct_stoc_renegotiate, tls_construct_ctos_renegotiate,
108 TLSEXT_TYPE_server_name,
109 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
110 | EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
112 tls_parse_ctos_server_name, tls_parse_stoc_server_name,
113 tls_construct_stoc_server_name, tls_construct_ctos_server_name,
116 #ifndef OPENSSL_NO_SRP
119 EXT_CLIENT_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
120 init_srp, tls_parse_ctos_srp, NULL, NULL, tls_construct_ctos_srp, NULL
125 #ifndef OPENSSL_NO_EC
127 TLSEXT_TYPE_ec_point_formats,
128 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
129 NULL, tls_parse_ctos_ec_pt_formats, tls_parse_stoc_ec_pt_formats,
130 tls_construct_stoc_ec_pt_formats, tls_construct_ctos_ec_pt_formats,
134 TLSEXT_TYPE_supported_groups,
135 EXT_CLIENT_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
136 NULL, tls_parse_ctos_supported_groups, NULL,
137 NULL /* TODO(TLS1.3): Need to add this */,
138 tls_construct_ctos_supported_groups, NULL
145 TLSEXT_TYPE_session_ticket,
146 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
147 init_session_ticket, tls_parse_ctos_session_ticket,
148 tls_parse_stoc_session_ticket, tls_construct_stoc_session_ticket,
149 tls_construct_ctos_session_ticket, NULL
152 TLSEXT_TYPE_signature_algorithms,
154 init_sig_algs, tls_parse_ctos_sig_algs, NULL, NULL,
155 tls_construct_ctos_sig_algs, NULL
157 #ifndef OPENSSL_NO_OCSP
159 TLSEXT_TYPE_status_request,
160 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
161 | EXT_TLS1_3_CERTIFICATE,
162 init_status_request, tls_parse_ctos_status_request,
163 tls_parse_stoc_status_request, tls_construct_stoc_status_request,
164 tls_construct_ctos_status_request, final_status_request
169 #ifndef OPENSSL_NO_NEXTPROTONEG
171 TLSEXT_TYPE_next_proto_neg,
172 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
173 init_npn, tls_parse_ctos_npn, tls_parse_stoc_npn,
174 tls_construct_stoc_next_proto_neg, tls_construct_ctos_npn, NULL
181 * Must appear in this list after server_name so that finalisation
182 * happens after server_name callbacks
184 TLSEXT_TYPE_application_layer_protocol_negotiation,
185 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
186 | EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
187 init_alpn, tls_parse_ctos_alpn, tls_parse_stoc_alpn,
188 tls_construct_stoc_alpn, tls_construct_ctos_alpn, final_alpn
190 #ifndef OPENSSL_NO_SRTP
192 TLSEXT_TYPE_use_srtp,
193 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
194 | EXT_TLS1_3_ENCRYPTED_EXTENSIONS | EXT_DTLS_ONLY,
195 init_srtp, tls_parse_ctos_use_srtp, tls_parse_stoc_use_srtp,
196 tls_construct_stoc_use_srtp, tls_construct_ctos_use_srtp, NULL
202 TLSEXT_TYPE_encrypt_then_mac,
203 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
204 init_etm, tls_parse_ctos_etm, tls_parse_stoc_etm,
205 tls_construct_stoc_etm, tls_construct_ctos_etm, NULL
207 #ifndef OPENSSL_NO_CT
209 TLSEXT_TYPE_signed_certificate_timestamp,
210 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
211 | EXT_TLS1_3_CERTIFICATE,
214 * No server side support for this, but can be provided by a custom
215 * extension. This is an exception to the rule that custom extensions
216 * cannot override built in ones.
218 NULL, tls_parse_stoc_sct, NULL, tls_construct_ctos_sct, NULL
224 TLSEXT_TYPE_extended_master_secret,
225 EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
226 init_ems, tls_parse_ctos_ems, tls_parse_stoc_ems,
227 tls_construct_stoc_ems, tls_construct_ctos_ems, final_ems
230 TLSEXT_TYPE_supported_versions,
231 EXT_CLIENT_HELLO | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY,
233 /* Processed inline as part of version selection */
234 NULL, NULL, NULL, tls_construct_ctos_supported_versions, NULL
238 * Must be in this list after supported_groups. We need that to have
239 * been parsed before we do this one.
241 TLSEXT_TYPE_key_share,
242 EXT_CLIENT_HELLO | EXT_TLS1_3_SERVER_HELLO
243 | EXT_TLS1_3_HELLO_RETRY_REQUEST | EXT_TLS_IMPLEMENTATION_ONLY
245 NULL, tls_parse_ctos_key_share, tls_parse_stoc_key_share,
246 tls_construct_stoc_key_share, tls_construct_ctos_key_share, NULL
250 * Special unsolicited ServerHello extension only used when
251 * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set
253 TLSEXT_TYPE_cryptopro_bug,
254 EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY,
255 NULL, NULL, NULL, tls_construct_stoc_cryptopro_bug, NULL, NULL
258 /* Last in the list because it must be added as the last extension */
262 /* We send this, but don't read it */
263 NULL, NULL, NULL, tls_construct_ctos_padding, NULL
268 * Verify whether we are allowed to use the extension |type| in the current
269 * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to
270 * indicate the extension is not allowed. If returning 1 then |*found| is set to
271 * 1 if we found a definition for the extension, and |*idx| is set to its index
273 static int verify_extension(SSL *s, unsigned int context, unsigned int type,
274 custom_ext_methods *meths, RAW_EXTENSION *rawexlist,
275 RAW_EXTENSION **found)
278 size_t builtin_num = OSSL_NELEM(ext_defs);
279 const EXTENSION_DEFINITION *thisext;
281 for (i = 0, thisext = ext_defs; i < builtin_num; i++, thisext++) {
282 if (type == thisext->type) {
283 /* Check we're allowed to use this extension in this context */
284 if ((context & thisext->context) == 0)
287 if (SSL_IS_DTLS(s)) {
288 if ((thisext->context & EXT_TLS_ONLY) != 0)
290 } else if ((thisext->context & EXT_DTLS_ONLY) != 0) {
294 *found = &rawexlist[i];
299 if ((context & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) == 0) {
301 * Custom extensions only apply to <=TLS1.2. This extension is unknown
302 * in this context - we allow it
308 /* Check the custom extensions */
310 for (i = builtin_num; i < builtin_num + meths->meths_count; i++) {
311 if (meths->meths[i - builtin_num].ext_type == type) {
312 *found = &rawexlist[i];
318 /* Unknown extension. We allow it */
324 * Check whether the context defined for an extension |extctx| means whether
325 * the extension is relevant for the current context |thisctx| or not. Returns
326 * 1 if the extension is relevant for this context, and 0 otherwise
328 static int extension_is_relevant(SSL *s, unsigned int extctx,
329 unsigned int thisctx)
332 && (extctx & EXT_TLS_IMPLEMENTATION_ONLY) != 0)
333 || (s->version == SSL3_VERSION
334 && (extctx & EXT_SSL3_ALLOWED) == 0)
336 && (extctx & EXT_TLS1_2_AND_BELOW_ONLY) != 0)
337 || (!SSL_IS_TLS13(s) && (extctx & EXT_TLS1_3_ONLY) != 0))
344 * Gather a list of all the extensions from the data in |packet]. |context|
345 * tells us which message this extension is for. The raw extension data is
346 * stored in |*res| on success. In the event of an error the alert type to use
347 * is stored in |*al|. We don't actually process the content of the extensions
348 * yet, except to check their types. This function also runs the initialiser
349 * functions for all known extensions (whether we have collected them or not).
350 * If successful the caller is responsible for freeing the contents of |*res|.
352 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
353 * more than one extension of the same type in a ClientHello or ServerHello.
354 * This function returns 1 if all extensions are unique and we have parsed their
355 * types, and 0 if the extensions contain duplicates, could not be successfully
356 * found, or an internal error occurred. We only check duplicates for
357 * extensions that we know about. We ignore others.
359 int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context,
360 RAW_EXTENSION **res, int *al)
362 PACKET extensions = *packet;
364 custom_ext_methods *exts = NULL;
365 RAW_EXTENSION *raw_extensions = NULL;
366 const EXTENSION_DEFINITION *thisexd;
371 * Initialise server side custom extensions. Client side is done during
372 * construction of extensions for the ClientHello.
374 if ((context & EXT_CLIENT_HELLO) != 0) {
375 exts = &s->cert->srv_ext;
376 custom_ext_init(&s->cert->srv_ext);
377 } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) {
378 exts = &s->cert->cli_ext;
381 raw_extensions = OPENSSL_zalloc((OSSL_NELEM(ext_defs)
382 + (exts != NULL ? exts->meths_count : 0))
383 * sizeof(*raw_extensions));
384 if (raw_extensions == NULL) {
385 *al = SSL_AD_INTERNAL_ERROR;
386 SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE);
390 while (PACKET_remaining(&extensions) > 0) {
393 RAW_EXTENSION *thisex;
395 if (!PACKET_get_net_2(&extensions, &type) ||
396 !PACKET_get_length_prefixed_2(&extensions, &extension)) {
397 SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION);
398 *al = SSL_AD_DECODE_ERROR;
402 * Verify this extension is allowed. We only check duplicates for
403 * extensions that we recognise.
405 if (!verify_extension(s, context, type, exts, raw_extensions, &thisex)
406 || (thisex != NULL && thisex->present == 1)) {
407 SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION);
408 *al = SSL_AD_ILLEGAL_PARAMETER;
411 if (thisex != NULL) {
412 thisex->data = extension;
419 * Initialise all known extensions relevant to this context, whether we have
422 for (thisexd = ext_defs, i = 0; i < OSSL_NELEM(ext_defs); i++, thisexd++) {
423 if(thisexd->init != NULL && (thisexd->context & context) != 0
424 && extension_is_relevant(s, thisexd->context, context)
425 && !thisexd->init(s, context)) {
426 *al = SSL_AD_INTERNAL_ERROR;
431 *res = raw_extensions;
435 OPENSSL_free(raw_extensions);
440 * Runs the parser for a given extension with index |idx|. |exts| contains the
441 * list of all parsed extensions previously collected by
442 * tls_collect_extensions(). The parser is only run if it is applicable for the
443 * given |context| and the parser has not already been run. Returns 1 on success
444 * or 0 on failure. In the event of a failure |*al| is populated with a suitable
445 * alert code. If an extension is not present this counted as success.
447 int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context,
448 RAW_EXTENSION *exts, int *al)
450 RAW_EXTENSION *currext = &exts[idx];
451 int (*parser)(SSL *s, PACKET *pkt, int *al) = NULL;
453 /* Skip if the extension is not present */
454 if (!currext->present)
457 if (s->tlsext_debug_cb)
458 s->tlsext_debug_cb(s, !s->server, currext->type,
459 PACKET_data(&currext->data),
460 PACKET_remaining(&currext->data),
461 s->tlsext_debug_arg);
463 /* Skip if we've already parsed this extension */
469 if (idx < OSSL_NELEM(ext_defs)) {
470 /* We are handling a built-in extension */
471 const EXTENSION_DEFINITION *extdef = &ext_defs[idx];
473 /* Check if extension is defined for our protocol. If not, skip */
474 if (!extension_is_relevant(s, extdef->context, context))
477 parser = s->server ? extdef->parse_ctos : extdef->parse_stoc;
480 return parser(s, &currext->data, al);
483 * If the parser is NULL we fall through to the custom extension
489 * This is a custom extension. We only allow this if it is a non
490 * resumed session on the server side.
492 * TODO(TLS1.3): We only allow old style <=TLS1.2 custom extensions.
493 * We're going to need a new mechanism for TLS1.3 to specify which
494 * messages to add the custom extensions to.
496 if ((!s->hit || !s->server)
498 & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) != 0
499 && custom_ext_parse(s, s->server, currext->type,
500 PACKET_data(&currext->data),
501 PACKET_remaining(&currext->data),
509 * Parse all remaining extensions that have not yet been parsed. Also calls the
510 * finalisation for all extensions at the end, whether we collected them or not.
511 * Returns 1 for success or 0 for failure. On failure, |*al| is populated with a
512 * suitable alert code.
514 int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, int *al)
516 size_t i, numexts = OSSL_NELEM(ext_defs);
517 const EXTENSION_DEFINITION *thisexd;
519 /* Calculate the number of extensions in the extensions list */
520 if ((context & EXT_CLIENT_HELLO) != 0) {
521 numexts += s->cert->srv_ext.meths_count;
522 } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) {
523 numexts += s->cert->cli_ext.meths_count;
526 /* Parse each extension in turn */
527 for (i = 0; i < numexts; i++) {
528 if (!tls_parse_extension(s, i, context, exts, al))
533 * Finalise all known extensions relevant to this context, whether we have
536 for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) {
537 if(thisexd->final != NULL
538 && (thisexd->context & context) != 0
539 && !thisexd->final(s, context, exts[i].present, al))
547 * Construct all the extensions relevant to the current |context| and write
548 * them to |pkt|. Returns 1 on success or 0 on failure. If a failure occurs then
549 * |al| is populated with a suitable alert code. On a failure construction stops
550 * at the first extension to fail to construct.
552 int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context,
556 int addcustom = 0, min_version, max_version = 0, reason, tmpal;
557 const EXTENSION_DEFINITION *thisexd;
560 * Normally if something goes wrong during construction it's an internal
561 * error. We can always override this later.
563 tmpal = SSL_AD_INTERNAL_ERROR;
565 if (!WPACKET_start_sub_packet_u16(pkt)
567 * If extensions are of zero length then we don't even add the
568 * extensions length bytes to a ClientHello/ServerHello in SSLv3
570 || ((context & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) != 0
571 && s->version == SSL3_VERSION
572 && !WPACKET_set_flags(pkt,
573 WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH))) {
574 SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
578 if ((context & EXT_CLIENT_HELLO) != 0) {
579 reason = ssl_get_client_min_max_version(s, &min_version, &max_version);
581 SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, reason);
586 /* Add custom extensions first */
587 if ((context & EXT_CLIENT_HELLO) != 0) {
588 custom_ext_init(&s->cert->cli_ext);
590 } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) {
592 * We already initialised the custom extensions during ClientHello
595 * TODO(TLS1.3): We're going to need a new custom extension mechanism
596 * for TLS1.3, so that custom extensions can specify which of the
597 * multiple message they wish to add themselves to.
602 if (addcustom && !custom_ext_add(s, s->server, pkt, &tmpal)) {
603 SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
607 for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) {
608 int (*construct)(SSL *s, WPACKET *pkt, int *al);
610 /* Skip if not relevant for our context */
611 if ((thisexd->context & context) == 0)
614 construct = s->server ? thisexd->construct_stoc
615 : thisexd->construct_ctos;
617 /* Check if this extension is defined for our protocol. If not, skip */
619 && (thisexd->context & EXT_TLS_IMPLEMENTATION_ONLY)
621 || (s->version == SSL3_VERSION
622 && (thisexd->context & EXT_SSL3_ALLOWED) == 0)
624 && (thisexd->context & EXT_TLS1_2_AND_BELOW_ONLY)
627 && (thisexd->context & EXT_TLS1_3_ONLY) != 0
628 && (context & EXT_CLIENT_HELLO) == 0)
629 || ((thisexd->context & EXT_TLS1_3_ONLY) != 0
630 && (context & EXT_CLIENT_HELLO) != 0
631 && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION))
632 || construct == NULL)
635 if (!construct(s, pkt, &tmpal))
639 if (!WPACKET_close(pkt)) {
640 SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
652 * Built in extension finalisation and initialisation functions. All initialise
653 * or finalise the associated extension type for the given |context|. For
654 * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
655 * otherwise. These functions return 1 on success or 0 on failure. In the event
656 * of a failure then |*al| is populated with a suitable error code.
659 static int final_renegotiate(SSL *s, unsigned int context, int sent,
664 * Check if we can connect to a server that doesn't support safe
667 if (!(s->options & SSL_OP_LEGACY_SERVER_CONNECT)
668 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
670 *al = SSL_AD_HANDSHAKE_FAILURE;
671 SSLerr(SSL_F_FINAL_RENEGOTIATE,
672 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
679 /* Need RI if renegotiating */
681 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
683 *al = SSL_AD_HANDSHAKE_FAILURE;
684 SSLerr(SSL_F_FINAL_RENEGOTIATE,
685 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
693 static int init_server_name(SSL *s, unsigned int context)
696 s->servername_done = 0;
701 static int final_server_name(SSL *s, unsigned int context, int sent,
704 int ret = SSL_TLSEXT_ERR_NOACK;
705 int altmp = SSL_AD_UNRECOGNIZED_NAME;
707 if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0)
708 ret = s->ctx->tlsext_servername_callback(s, &altmp,
709 s->ctx->tlsext_servername_arg);
710 else if (s->initial_ctx != NULL
711 && s->initial_ctx->tlsext_servername_callback != 0)
712 ret = s->initial_ctx->tlsext_servername_callback(s, &altmp,
713 s->initial_ctx->tlsext_servername_arg);
716 case SSL_TLSEXT_ERR_ALERT_FATAL:
720 case SSL_TLSEXT_ERR_ALERT_WARNING:
724 case SSL_TLSEXT_ERR_NOACK:
725 s->servername_done = 0;
733 #ifndef OPENSSL_NO_EC
734 static int final_ec_pt_formats(SSL *s, unsigned int context, int sent,
737 unsigned long alg_k, alg_a;
742 alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
743 alg_a = s->s3->tmp.new_cipher->algorithm_auth;
746 * If we are client and using an elliptic curve cryptography cipher
747 * suite, then if server returns an EC point formats lists extension it
748 * must contain uncompressed.
750 if (s->tlsext_ecpointformatlist != NULL
751 && s->tlsext_ecpointformatlist_length > 0
752 && s->session->tlsext_ecpointformatlist != NULL
753 && s->session->tlsext_ecpointformatlist_length > 0
754 && ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA))) {
755 /* we are using an ECC cipher */
757 unsigned char *list = s->session->tlsext_ecpointformatlist;
759 for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++) {
760 if (*list++ == TLSEXT_ECPOINTFORMAT_uncompressed)
763 if (i == s->session->tlsext_ecpointformatlist_length) {
764 SSLerr(SSL_F_FINAL_EC_PT_FORMATS,
765 SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
774 static int init_session_ticket(SSL *s, unsigned int context)
777 s->tlsext_ticket_expected = 0;
782 #ifndef OPENSSL_NO_OCSP
783 static int init_status_request(SSL *s, unsigned int context)
786 s->tlsext_status_type = TLSEXT_STATUSTYPE_nothing;
791 static int final_status_request(SSL *s, unsigned int context, int sent,
798 * Ensure we get sensible values passed to tlsext_status_cb in the event
799 * that we don't receive a status message
801 OPENSSL_free(s->tlsext_ocsp_resp);
802 s->tlsext_ocsp_resp = NULL;
803 s->tlsext_ocsp_resplen = 0;
809 #ifndef OPENSSL_NO_NEXTPROTONEG
810 static int init_npn(SSL *s, unsigned int context)
812 s->s3->next_proto_neg_seen = 0;
818 static int init_alpn(SSL *s, unsigned int context)
820 OPENSSL_free(s->s3->alpn_selected);
821 s->s3->alpn_selected = NULL;
823 s->s3->alpn_selected_len = 0;
824 OPENSSL_free(s->s3->alpn_proposed);
825 s->s3->alpn_proposed = NULL;
826 s->s3->alpn_proposed_len = 0;
831 static int final_alpn(SSL *s, unsigned int context, int sent, int *al)
833 const unsigned char *selected = NULL;
834 unsigned char selected_len = 0;
839 if (s->ctx->alpn_select_cb != NULL && s->s3->alpn_proposed != NULL) {
840 int r = s->ctx->alpn_select_cb(s, &selected, &selected_len,
841 s->s3->alpn_proposed,
842 (unsigned int)s->s3->alpn_proposed_len,
843 s->ctx->alpn_select_cb_arg);
845 if (r == SSL_TLSEXT_ERR_OK) {
846 OPENSSL_free(s->s3->alpn_selected);
847 s->s3->alpn_selected = OPENSSL_memdup(selected, selected_len);
848 if (s->s3->alpn_selected == NULL) {
849 *al = SSL_AD_INTERNAL_ERROR;
852 s->s3->alpn_selected_len = selected_len;
853 #ifndef OPENSSL_NO_NEXTPROTONEG
854 /* ALPN takes precedence over NPN. */
855 s->s3->next_proto_neg_seen = 0;
858 *al = SSL_AD_NO_APPLICATION_PROTOCOL;
866 static int init_sig_algs(SSL *s, unsigned int context)
868 /* Clear any signature algorithms extension received */
869 OPENSSL_free(s->s3->tmp.peer_sigalgs);
870 s->s3->tmp.peer_sigalgs = NULL;
875 #ifndef OPENSSL_NO_SRP
876 static int init_srp(SSL *s, unsigned int context)
878 OPENSSL_free(s->srp_ctx.login);
879 s->srp_ctx.login = NULL;
885 static int init_etm(SSL *s, unsigned int context)
887 s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC;
892 static int init_ems(SSL *s, unsigned int context)
895 s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS;
900 static int final_ems(SSL *s, unsigned int context, int sent, int *al)
902 if (!s->server && s->hit) {
904 * Check extended master secret extension is consistent with
907 if (!(s->s3->flags & TLS1_FLAGS_RECEIVED_EXTMS) !=
908 !(s->session->flags & SSL_SESS_FLAG_EXTMS)) {
909 *al = SSL_AD_HANDSHAKE_FAILURE;
910 SSLerr(SSL_F_FINAL_EMS, SSL_R_INCONSISTENT_EXTMS);
918 #ifndef OPENSSL_NO_SRTP
919 static int init_srtp(SSL *s, unsigned int context)
922 s->srtp_profile = NULL;