2 * Copyright 2016-2017 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
11 #include "internal/nelem.h"
12 #include "internal/cryptlib.h"
13 #include "../ssl_locl.h"
14 #include "statem_locl.h"
16 static int final_renegotiate(SSL *s, unsigned int context, int sent);
17 static int init_server_name(SSL *s, unsigned int context);
18 static int final_server_name(SSL *s, unsigned int context, int sent);
20 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);
26 #ifndef OPENSSL_NO_NEXTPROTONEG
27 static int init_npn(SSL *s, unsigned int context);
29 static int init_alpn(SSL *s, unsigned int context);
30 static int final_alpn(SSL *s, unsigned int context, int sent);
31 static int init_sig_algs(SSL *s, unsigned int context);
32 static int init_certificate_authorities(SSL *s, unsigned int context);
33 static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
37 static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt,
38 unsigned int context, X509 *x,
40 #ifndef OPENSSL_NO_SRP
41 static int init_srp(SSL *s, unsigned int context);
43 static int init_etm(SSL *s, unsigned int context);
44 static int init_ems(SSL *s, unsigned int context);
45 static int final_ems(SSL *s, unsigned int context, int sent);
46 static int init_psk_kex_modes(SSL *s, unsigned int context);
48 static int final_key_share(SSL *s, unsigned int context, int sent);
50 #ifndef OPENSSL_NO_SRTP
51 static int init_srtp(SSL *s, unsigned int context);
53 static int final_sig_algs(SSL *s, unsigned int context, int sent);
54 static int final_early_data(SSL *s, unsigned int context, int sent);
55 static int final_maxfragmentlen(SSL *s, unsigned int context, int sent);
57 /* Structure to define a built-in extension */
58 typedef struct extensions_definition_st {
59 /* The defined type for the extension */
62 * The context that this extension applies to, e.g. what messages and
67 * Initialise extension before parsing. Always called for relevant contexts
68 * even if extension not present
70 int (*init)(SSL *s, unsigned int context);
71 /* Parse extension sent from client to server */
72 int (*parse_ctos)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
74 /* Parse extension send from server to client */
75 int (*parse_stoc)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
77 /* Construct extension sent from server to client */
78 EXT_RETURN (*construct_stoc)(SSL *s, WPACKET *pkt, unsigned int context,
79 X509 *x, size_t chainidx);
80 /* Construct extension sent from client to server */
81 EXT_RETURN (*construct_ctos)(SSL *s, WPACKET *pkt, unsigned int context,
82 X509 *x, size_t chainidx);
84 * Finalise extension after parsing. Always called where an extensions was
85 * initialised even if the extension was not present. |sent| is set to 1 if
86 * the extension was seen, or 0 otherwise.
88 int (*final)(SSL *s, unsigned int context, int sent);
89 } EXTENSION_DEFINITION;
92 * Definitions of all built-in extensions. NOTE: Changes in the number or order
93 * of these extensions should be mirrored with equivalent changes to the
94 * indexes ( TLSEXT_IDX_* ) defined in ssl_locl.h.
95 * Each extension has an initialiser, a client and
96 * server side parser and a finaliser. The initialiser is called (if the
97 * extension is relevant to the given context) even if we did not see the
98 * extension in the message that we received. The parser functions are only
99 * called if we see the extension in the message. The finalisers are always
100 * called if the initialiser was called.
101 * There are also server and client side constructor functions which are always
102 * called during message construction if the extension is relevant for the
104 * The initialisation, parsing, finalisation and construction functions are
105 * always called in the order defined in this list. Some extensions may depend
106 * on others having been processed first, so the order of this list is
108 * The extension context is defined by a series of flags which specify which
109 * messages the extension is relevant to. These flags also specify whether the
110 * extension is relevant to a particular protocol or protocol version.
112 * TODO(TLS1.3): Make sure we have a test to check the consistency of these
114 * NOTE: WebSphere Application Server 7+ cannot handle empty extensions at
115 * the end, keep these extensions before signature_algorithm.
117 #define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL }
118 static const EXTENSION_DEFINITION ext_defs[] = {
120 TLSEXT_TYPE_renegotiate,
121 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
122 | SSL_EXT_SSL3_ALLOWED | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
123 NULL, tls_parse_ctos_renegotiate, tls_parse_stoc_renegotiate,
124 tls_construct_stoc_renegotiate, tls_construct_ctos_renegotiate,
128 TLSEXT_TYPE_server_name,
129 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
130 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
132 tls_parse_ctos_server_name, tls_parse_stoc_server_name,
133 tls_construct_stoc_server_name, tls_construct_ctos_server_name,
137 TLSEXT_TYPE_max_fragment_length,
138 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
139 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
140 NULL, tls_parse_ctos_maxfragmentlen, tls_parse_stoc_maxfragmentlen,
141 tls_construct_stoc_maxfragmentlen, tls_construct_ctos_maxfragmentlen,
144 #ifndef OPENSSL_NO_SRP
147 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
148 init_srp, tls_parse_ctos_srp, NULL, NULL, tls_construct_ctos_srp, NULL
153 #ifndef OPENSSL_NO_EC
155 TLSEXT_TYPE_ec_point_formats,
156 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
157 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
158 NULL, tls_parse_ctos_ec_pt_formats, tls_parse_stoc_ec_pt_formats,
159 tls_construct_stoc_ec_pt_formats, tls_construct_ctos_ec_pt_formats,
163 TLSEXT_TYPE_supported_groups,
164 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
165 NULL, tls_parse_ctos_supported_groups, NULL,
166 tls_construct_stoc_supported_groups,
167 tls_construct_ctos_supported_groups, NULL
174 TLSEXT_TYPE_session_ticket,
175 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
176 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
177 init_session_ticket, tls_parse_ctos_session_ticket,
178 tls_parse_stoc_session_ticket, tls_construct_stoc_session_ticket,
179 tls_construct_ctos_session_ticket, NULL
181 #ifndef OPENSSL_NO_OCSP
183 TLSEXT_TYPE_status_request,
184 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
185 | SSL_EXT_TLS1_3_CERTIFICATE,
186 init_status_request, tls_parse_ctos_status_request,
187 tls_parse_stoc_status_request, tls_construct_stoc_status_request,
188 tls_construct_ctos_status_request, NULL
193 #ifndef OPENSSL_NO_NEXTPROTONEG
195 TLSEXT_TYPE_next_proto_neg,
196 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
197 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
198 init_npn, tls_parse_ctos_npn, tls_parse_stoc_npn,
199 tls_construct_stoc_next_proto_neg, tls_construct_ctos_npn, NULL
206 * Must appear in this list after server_name so that finalisation
207 * happens after server_name callbacks
209 TLSEXT_TYPE_application_layer_protocol_negotiation,
210 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
211 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
212 init_alpn, tls_parse_ctos_alpn, tls_parse_stoc_alpn,
213 tls_construct_stoc_alpn, tls_construct_ctos_alpn, final_alpn
215 #ifndef OPENSSL_NO_SRTP
217 TLSEXT_TYPE_use_srtp,
218 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
219 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS | SSL_EXT_DTLS_ONLY,
220 init_srtp, tls_parse_ctos_use_srtp, tls_parse_stoc_use_srtp,
221 tls_construct_stoc_use_srtp, tls_construct_ctos_use_srtp, NULL
227 TLSEXT_TYPE_encrypt_then_mac,
228 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
229 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
230 init_etm, tls_parse_ctos_etm, tls_parse_stoc_etm,
231 tls_construct_stoc_etm, tls_construct_ctos_etm, NULL
233 #ifndef OPENSSL_NO_CT
235 TLSEXT_TYPE_signed_certificate_timestamp,
236 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
237 | SSL_EXT_TLS1_3_CERTIFICATE,
240 * No server side support for this, but can be provided by a custom
241 * extension. This is an exception to the rule that custom extensions
242 * cannot override built in ones.
244 NULL, tls_parse_stoc_sct, NULL, tls_construct_ctos_sct, NULL
250 TLSEXT_TYPE_extended_master_secret,
251 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
252 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
253 init_ems, tls_parse_ctos_ems, tls_parse_stoc_ems,
254 tls_construct_stoc_ems, tls_construct_ctos_ems, final_ems
257 TLSEXT_TYPE_signature_algorithms,
258 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
259 init_sig_algs, tls_parse_ctos_sig_algs,
260 tls_parse_ctos_sig_algs, tls_construct_ctos_sig_algs,
261 tls_construct_ctos_sig_algs, final_sig_algs
264 TLSEXT_TYPE_supported_versions,
265 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
266 | SSL_EXT_TLS1_3_SERVER_HELLO | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
267 | SSL_EXT_TLS_IMPLEMENTATION_ONLY,
269 /* Processed inline as part of version selection */
270 NULL, tls_parse_stoc_supported_versions,
271 tls_construct_stoc_supported_versions,
272 tls_construct_ctos_supported_versions, NULL
275 TLSEXT_TYPE_psk_kex_modes,
276 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS_IMPLEMENTATION_ONLY
277 | SSL_EXT_TLS1_3_ONLY,
278 init_psk_kex_modes, tls_parse_ctos_psk_kex_modes, NULL, NULL,
279 tls_construct_ctos_psk_kex_modes, NULL
281 #ifndef OPENSSL_NO_EC
284 * Must be in this list after supported_groups. We need that to have
285 * been parsed before we do this one.
287 TLSEXT_TYPE_key_share,
288 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO
289 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST | SSL_EXT_TLS_IMPLEMENTATION_ONLY
290 | SSL_EXT_TLS1_3_ONLY,
291 NULL, tls_parse_ctos_key_share, tls_parse_stoc_key_share,
292 tls_construct_stoc_key_share, tls_construct_ctos_key_share,
298 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
299 | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
300 NULL, NULL, tls_parse_stoc_cookie, NULL, tls_construct_ctos_cookie,
305 * Special unsolicited ServerHello extension only used when
306 * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set
308 TLSEXT_TYPE_cryptopro_bug,
309 SSL_EXT_TLS1_2_SERVER_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
310 NULL, NULL, NULL, tls_construct_stoc_cryptopro_bug, NULL, NULL
313 TLSEXT_TYPE_early_data,
314 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
315 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
316 NULL, tls_parse_ctos_early_data, tls_parse_stoc_early_data,
317 tls_construct_stoc_early_data, tls_construct_ctos_early_data,
321 TLSEXT_TYPE_certificate_authorities,
322 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
323 | SSL_EXT_TLS1_3_ONLY,
324 init_certificate_authorities,
325 tls_parse_certificate_authorities, tls_parse_certificate_authorities,
326 tls_construct_certificate_authorities,
327 tls_construct_certificate_authorities, NULL,
330 /* Must be immediately before pre_shared_key */
332 SSL_EXT_CLIENT_HELLO,
334 /* We send this, but don't read it */
335 NULL, NULL, NULL, tls_construct_ctos_padding, NULL
338 /* Required by the TLSv1.3 spec to always be the last extension */
340 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO
341 | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
342 NULL, tls_parse_ctos_psk, tls_parse_stoc_psk, tls_construct_stoc_psk,
343 tls_construct_ctos_psk, NULL
347 /* Check whether an extension's context matches the current context */
348 static int validate_context(SSL *s, unsigned int extctx, unsigned int thisctx)
350 /* Check we're allowed to use this extension in this context */
351 if ((thisctx & extctx) == 0)
354 if (SSL_IS_DTLS(s)) {
355 if ((extctx & SSL_EXT_TLS_ONLY) != 0)
357 } else if ((extctx & SSL_EXT_DTLS_ONLY) != 0) {
364 int tls_validate_all_contexts(SSL *s, unsigned int thisctx, RAW_EXTENSION *exts)
366 size_t i, num_exts, builtin_num = OSSL_NELEM(ext_defs), offset;
367 RAW_EXTENSION *thisext;
368 unsigned int context;
369 ENDPOINT role = ENDPOINT_BOTH;
371 if ((thisctx & SSL_EXT_CLIENT_HELLO) != 0)
372 role = ENDPOINT_SERVER;
373 else if ((thisctx & SSL_EXT_TLS1_2_SERVER_HELLO) != 0)
374 role = ENDPOINT_CLIENT;
376 /* Calculate the number of extensions in the extensions list */
377 num_exts = builtin_num + s->cert->custext.meths_count;
379 for (thisext = exts, i = 0; i < num_exts; i++, thisext++) {
380 if (!thisext->present)
383 if (i < builtin_num) {
384 context = ext_defs[i].context;
386 custom_ext_method *meth = NULL;
388 meth = custom_ext_find(&s->cert->custext, role, thisext->type,
390 if (!ossl_assert(meth != NULL))
392 context = meth->context;
395 if (!validate_context(s, context, thisctx))
403 * Verify whether we are allowed to use the extension |type| in the current
404 * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to
405 * indicate the extension is not allowed. If returning 1 then |*found| is set to
406 * the definition for the extension we found.
408 static int verify_extension(SSL *s, unsigned int context, unsigned int type,
409 custom_ext_methods *meths, RAW_EXTENSION *rawexlist,
410 RAW_EXTENSION **found)
413 size_t builtin_num = OSSL_NELEM(ext_defs);
414 const EXTENSION_DEFINITION *thisext;
416 for (i = 0, thisext = ext_defs; i < builtin_num; i++, thisext++) {
417 if (type == thisext->type) {
418 if (!validate_context(s, thisext->context, context))
421 *found = &rawexlist[i];
426 /* Check the custom extensions */
429 ENDPOINT role = ENDPOINT_BOTH;
430 custom_ext_method *meth = NULL;
432 if ((context & SSL_EXT_CLIENT_HELLO) != 0)
433 role = ENDPOINT_SERVER;
434 else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0)
435 role = ENDPOINT_CLIENT;
437 meth = custom_ext_find(meths, role, type, &offset);
439 if (!validate_context(s, meth->context, context))
441 *found = &rawexlist[offset + builtin_num];
446 /* Unknown extension. We allow it */
452 * Check whether the context defined for an extension |extctx| means whether
453 * the extension is relevant for the current context |thisctx| or not. Returns
454 * 1 if the extension is relevant for this context, and 0 otherwise
456 int extension_is_relevant(SSL *s, unsigned int extctx, unsigned int thisctx)
461 * For HRR we haven't selected the version yet but we know it will be
464 if ((thisctx & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0)
467 is_tls13 = SSL_IS_TLS13(s);
470 && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0)
471 || (s->version == SSL3_VERSION
472 && (extctx & SSL_EXT_SSL3_ALLOWED) == 0)
473 || (is_tls13 && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0)
474 || (!is_tls13 && (extctx & SSL_EXT_TLS1_3_ONLY) != 0)
475 || (s->hit && (extctx & SSL_EXT_IGNORE_ON_RESUMPTION) != 0))
482 * Gather a list of all the extensions from the data in |packet]. |context|
483 * tells us which message this extension is for. The raw extension data is
484 * stored in |*res| on success. We don't actually process the content of the
485 * extensions yet, except to check their types. This function also runs the
486 * initialiser functions for all known extensions if |init| is nonzero (whether
487 * we have collected them or not). If successful the caller is responsible for
488 * freeing the contents of |*res|.
490 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
491 * more than one extension of the same type in a ClientHello or ServerHello.
492 * This function returns 1 if all extensions are unique and we have parsed their
493 * types, and 0 if the extensions contain duplicates, could not be successfully
494 * found, or an internal error occurred. We only check duplicates for
495 * extensions that we know about. We ignore others.
497 int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context,
498 RAW_EXTENSION **res, size_t *len, int init)
500 PACKET extensions = *packet;
503 custom_ext_methods *exts = &s->cert->custext;
504 RAW_EXTENSION *raw_extensions = NULL;
505 const EXTENSION_DEFINITION *thisexd;
510 * Initialise server side custom extensions. Client side is done during
511 * construction of extensions for the ClientHello.
513 if ((context & SSL_EXT_CLIENT_HELLO) != 0)
514 custom_ext_init(&s->cert->custext);
516 num_exts = OSSL_NELEM(ext_defs) + (exts != NULL ? exts->meths_count : 0);
517 raw_extensions = OPENSSL_zalloc(num_exts * sizeof(*raw_extensions));
518 if (raw_extensions == NULL) {
519 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_COLLECT_EXTENSIONS,
520 ERR_R_MALLOC_FAILURE);
525 while (PACKET_remaining(&extensions) > 0) {
526 unsigned int type, idx;
528 RAW_EXTENSION *thisex;
530 if (!PACKET_get_net_2(&extensions, &type) ||
531 !PACKET_get_length_prefixed_2(&extensions, &extension)) {
532 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_COLLECT_EXTENSIONS,
533 SSL_R_BAD_EXTENSION);
537 * Verify this extension is allowed. We only check duplicates for
538 * extensions that we recognise. We also have a special case for the
539 * PSK extension, which must be the last one in the ClientHello.
541 if (!verify_extension(s, context, type, exts, raw_extensions, &thisex)
542 || (thisex != NULL && thisex->present == 1)
543 || (type == TLSEXT_TYPE_psk
544 && (context & SSL_EXT_CLIENT_HELLO) != 0
545 && PACKET_remaining(&extensions) != 0)) {
546 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_COLLECT_EXTENSIONS,
547 SSL_R_BAD_EXTENSION);
550 idx = thisex - raw_extensions;
552 * Check that we requested this extension (if appropriate). Requests can
553 * be sent in the ClientHello and CertificateRequest. Unsolicited
554 * extensions can be sent in the NewSessionTicket. We only do this for
555 * the built-in extensions. Custom extensions have a different but
556 * similar check elsewhere.
558 * - The HRR cookie extension is unsolicited
559 * - The renegotiate extension is unsolicited (the client signals
560 * support via an SCSV)
561 * - The signed_certificate_timestamp extension can be provided by a
562 * custom extension or by the built-in version. We let the extension
563 * itself handle unsolicited response checks.
565 if (idx < OSSL_NELEM(ext_defs)
566 && (context & (SSL_EXT_CLIENT_HELLO
567 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
568 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) == 0
569 && type != TLSEXT_TYPE_cookie
570 && type != TLSEXT_TYPE_renegotiate
571 && type != TLSEXT_TYPE_signed_certificate_timestamp
572 && (s->ext.extflags[idx] & SSL_EXT_FLAG_SENT) == 0) {
573 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION,
574 SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_UNSOLICITED_EXTENSION);
577 if (thisex != NULL) {
578 thisex->data = extension;
581 thisex->received_order = i++;
583 s->ext.debug_cb(s, !s->server, thisex->type,
584 PACKET_data(&thisex->data),
585 PACKET_remaining(&thisex->data),
592 * Initialise all known extensions relevant to this context,
593 * whether we have found them or not
595 for (thisexd = ext_defs, i = 0; i < OSSL_NELEM(ext_defs);
597 if (thisexd->init != NULL && (thisexd->context & context) != 0
598 && extension_is_relevant(s, thisexd->context, context)
599 && !thisexd->init(s, context)) {
600 /* SSLfatal() already called */
606 *res = raw_extensions;
612 OPENSSL_free(raw_extensions);
617 * Runs the parser for a given extension with index |idx|. |exts| contains the
618 * list of all parsed extensions previously collected by
619 * tls_collect_extensions(). The parser is only run if it is applicable for the
620 * given |context| and the parser has not already been run. If this is for a
621 * Certificate message, then we also provide the parser with the relevant
622 * Certificate |x| and its position in the |chainidx| with 0 being the first
623 * Certificate. Returns 1 on success or 0 on failure. If an extension is not
624 * present this counted as success.
626 int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context,
627 RAW_EXTENSION *exts, X509 *x, size_t chainidx)
629 RAW_EXTENSION *currext = &exts[idx];
630 int (*parser)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
631 size_t chainidx) = NULL;
633 /* Skip if the extension is not present */
634 if (!currext->present)
637 /* Skip if we've already parsed this extension */
643 if (idx < OSSL_NELEM(ext_defs)) {
644 /* We are handling a built-in extension */
645 const EXTENSION_DEFINITION *extdef = &ext_defs[idx];
647 /* Check if extension is defined for our protocol. If not, skip */
648 if (!extension_is_relevant(s, extdef->context, context))
651 parser = s->server ? extdef->parse_ctos : extdef->parse_stoc;
654 return parser(s, &currext->data, context, x, chainidx);
657 * If the parser is NULL we fall through to the custom extension
662 /* Parse custom extensions */
663 return custom_ext_parse(s, context, currext->type,
664 PACKET_data(&currext->data),
665 PACKET_remaining(&currext->data),
670 * Parse all remaining extensions that have not yet been parsed. Also calls the
671 * finalisation for all extensions at the end if |fin| is nonzero, whether we
672 * collected them or not. Returns 1 for success or 0 for failure. If we are
673 * working on a Certificate message then we also pass the Certificate |x| and
674 * its position in the |chainidx|, with 0 being the first certificate.
676 int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, X509 *x,
677 size_t chainidx, int fin)
679 size_t i, numexts = OSSL_NELEM(ext_defs);
680 const EXTENSION_DEFINITION *thisexd;
682 /* Calculate the number of extensions in the extensions list */
683 numexts += s->cert->custext.meths_count;
685 /* Parse each extension in turn */
686 for (i = 0; i < numexts; i++) {
687 if (!tls_parse_extension(s, i, context, exts, x, chainidx)) {
688 /* SSLfatal() already called */
695 * Finalise all known extensions relevant to this context,
696 * whether we have found them or not
698 for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs);
700 if (thisexd->final != NULL && (thisexd->context & context) != 0
701 && !thisexd->final(s, context, exts[i].present)) {
702 /* SSLfatal() already called */
711 int should_add_extension(SSL *s, unsigned int extctx, unsigned int thisctx,
714 /* Skip if not relevant for our context */
715 if ((extctx & thisctx) == 0)
718 /* Check if this extension is defined for our protocol. If not, skip */
719 if ((SSL_IS_DTLS(s) && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0)
720 || (s->version == SSL3_VERSION
721 && (extctx & SSL_EXT_SSL3_ALLOWED) == 0)
723 && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0)
725 && (extctx & SSL_EXT_TLS1_3_ONLY) != 0
726 && (thisctx & SSL_EXT_CLIENT_HELLO) == 0)
727 || ((extctx & SSL_EXT_TLS1_3_ONLY) != 0
728 && (thisctx & SSL_EXT_CLIENT_HELLO) != 0
729 && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION)))
736 * Construct all the extensions relevant to the current |context| and write
737 * them to |pkt|. If this is an extension for a Certificate in a Certificate
738 * message, then |x| will be set to the Certificate we are handling, and
739 * |chainidx| will indicate the position in the chainidx we are processing (with
740 * 0 being the first in the chain). Returns 1 on success or 0 on failure. On a
741 * failure construction stops at the first extension to fail to construct.
743 int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context,
744 X509 *x, size_t chainidx)
747 int min_version, max_version = 0, reason;
748 const EXTENSION_DEFINITION *thisexd;
750 if (!WPACKET_start_sub_packet_u16(pkt)
752 * If extensions are of zero length then we don't even add the
753 * extensions length bytes to a ClientHello/ServerHello
757 (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) != 0
758 && !WPACKET_set_flags(pkt,
759 WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH))) {
760 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_EXTENSIONS,
761 ERR_R_INTERNAL_ERROR);
765 if ((context & SSL_EXT_CLIENT_HELLO) != 0) {
766 reason = ssl_get_min_max_version(s, &min_version, &max_version);
768 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_EXTENSIONS,
774 /* Add custom extensions first */
775 if ((context & SSL_EXT_CLIENT_HELLO) != 0) {
776 /* On the server side with initialise during ClientHello parsing */
777 custom_ext_init(&s->cert->custext);
779 if (!custom_ext_add(s, context, pkt, x, chainidx, max_version)) {
780 /* SSLfatal() already called */
784 for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) {
785 EXT_RETURN (*construct)(SSL *s, WPACKET *pkt, unsigned int context,
786 X509 *x, size_t chainidx);
789 /* Skip if not relevant for our context */
790 if (!should_add_extension(s, thisexd->context, context, max_version))
793 construct = s->server ? thisexd->construct_stoc
794 : thisexd->construct_ctos;
796 if (construct == NULL)
799 ret = construct(s, pkt, context, x, chainidx);
800 if (ret == EXT_RETURN_FAIL) {
801 /* SSLfatal() already called */
804 if (ret == EXT_RETURN_SENT
805 && (context & (SSL_EXT_CLIENT_HELLO
806 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
807 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) != 0)
808 s->ext.extflags[i] |= SSL_EXT_FLAG_SENT;
811 if (!WPACKET_close(pkt)) {
812 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_EXTENSIONS,
813 ERR_R_INTERNAL_ERROR);
821 * Built in extension finalisation and initialisation functions. All initialise
822 * or finalise the associated extension type for the given |context|. For
823 * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
824 * otherwise. These functions return 1 on success or 0 on failure.
827 static int final_renegotiate(SSL *s, unsigned int context, int sent)
831 * Check if we can connect to a server that doesn't support safe
834 if (!(s->options & SSL_OP_LEGACY_SERVER_CONNECT)
835 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
837 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_FINAL_RENEGOTIATE,
838 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
845 /* Need RI if renegotiating */
847 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
849 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_FINAL_RENEGOTIATE,
850 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
858 static int init_server_name(SSL *s, unsigned int context)
861 s->servername_done = 0;
866 static int final_server_name(SSL *s, unsigned int context, int sent)
868 int ret = SSL_TLSEXT_ERR_NOACK, discard;
869 int altmp = SSL_AD_UNRECOGNIZED_NAME;
870 int was_ticket = (SSL_get_options(s) & SSL_OP_NO_TICKET) == 0;
872 if (s->ctx != NULL && s->ctx->ext.servername_cb != 0)
873 ret = s->ctx->ext.servername_cb(s, &altmp,
874 s->ctx->ext.servername_arg);
875 else if (s->session_ctx != NULL
876 && s->session_ctx->ext.servername_cb != 0)
877 ret = s->session_ctx->ext.servername_cb(s, &altmp,
878 s->session_ctx->ext.servername_arg);
881 OPENSSL_free(s->session->ext.hostname);
882 s->session->ext.hostname = NULL;
886 * If we switched contexts (whether here or in the client_hello callback),
887 * move the sess_accept increment from the session_ctx to the new
888 * context, to avoid the confusing situation of having sess_accept_good
889 * exceed sess_accept (zero) for the new context.
891 if (SSL_IS_FIRST_HANDSHAKE(s) && s->ctx != s->session_ctx) {
892 CRYPTO_atomic_add(&s->ctx->stats.sess_accept, 1, &discard,
894 CRYPTO_atomic_add(&s->session_ctx->stats.sess_accept, -1, &discard,
895 s->session_ctx->lock);
899 * If we're expecting to send a ticket, and tickets were previously enabled,
900 * and now tickets are disabled, then turn off expected ticket.
901 * Also, if this is not a resumption, create a new session ID
903 if (ret == SSL_TLSEXT_ERR_OK && s->ext.ticket_expected
904 && was_ticket && (SSL_get_options(s) & SSL_OP_NO_TICKET) != 0) {
905 s->ext.ticket_expected = 0;
907 SSL_SESSION* ss = SSL_get_session(s);
910 OPENSSL_free(ss->ext.tick);
913 ss->ext.tick_lifetime_hint = 0;
914 ss->ext.tick_age_add = 0;
915 ss->ext.tick_identity = 0;
916 if (!ssl_generate_session_id(s, ss)) {
917 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_SERVER_NAME,
918 ERR_R_INTERNAL_ERROR);
922 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_SERVER_NAME,
923 ERR_R_INTERNAL_ERROR);
930 case SSL_TLSEXT_ERR_ALERT_FATAL:
931 SSLfatal(s, altmp, SSL_F_FINAL_SERVER_NAME, SSL_R_CALLBACK_FAILED);
934 case SSL_TLSEXT_ERR_ALERT_WARNING:
935 ssl3_send_alert(s, SSL3_AL_WARNING, altmp);
938 case SSL_TLSEXT_ERR_NOACK:
939 s->servername_done = 0;
947 #ifndef OPENSSL_NO_EC
948 static int final_ec_pt_formats(SSL *s, unsigned int context, int sent)
950 unsigned long alg_k, alg_a;
955 alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
956 alg_a = s->s3->tmp.new_cipher->algorithm_auth;
959 * If we are client and using an elliptic curve cryptography cipher
960 * suite, then if server returns an EC point formats lists extension it
961 * must contain uncompressed.
963 if (s->ext.ecpointformats != NULL
964 && s->ext.ecpointformats_len > 0
965 && s->session->ext.ecpointformats != NULL
966 && s->session->ext.ecpointformats_len > 0
967 && ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA))) {
968 /* we are using an ECC cipher */
970 unsigned char *list = s->session->ext.ecpointformats;
972 for (i = 0; i < s->session->ext.ecpointformats_len; i++) {
973 if (*list++ == TLSEXT_ECPOINTFORMAT_uncompressed)
976 if (i == s->session->ext.ecpointformats_len) {
977 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_FINAL_EC_PT_FORMATS,
978 SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
987 static int init_session_ticket(SSL *s, unsigned int context)
990 s->ext.ticket_expected = 0;
995 #ifndef OPENSSL_NO_OCSP
996 static int init_status_request(SSL *s, unsigned int context)
999 s->ext.status_type = TLSEXT_STATUSTYPE_nothing;
1002 * Ensure we get sensible values passed to tlsext_status_cb in the event
1003 * that we don't receive a status message
1005 OPENSSL_free(s->ext.ocsp.resp);
1006 s->ext.ocsp.resp = NULL;
1007 s->ext.ocsp.resp_len = 0;
1014 #ifndef OPENSSL_NO_NEXTPROTONEG
1015 static int init_npn(SSL *s, unsigned int context)
1017 s->s3->npn_seen = 0;
1023 static int init_alpn(SSL *s, unsigned int context)
1025 OPENSSL_free(s->s3->alpn_selected);
1026 s->s3->alpn_selected = NULL;
1027 s->s3->alpn_selected_len = 0;
1029 OPENSSL_free(s->s3->alpn_proposed);
1030 s->s3->alpn_proposed = NULL;
1031 s->s3->alpn_proposed_len = 0;
1036 static int final_alpn(SSL *s, unsigned int context, int sent)
1038 if (!s->server && !sent && s->session->ext.alpn_selected != NULL)
1039 s->ext.early_data_ok = 0;
1041 if (!s->server || !SSL_IS_TLS13(s))
1045 * Call alpn_select callback if needed. Has to be done after SNI and
1046 * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
1047 * we also have to do this before we decide whether to accept early_data.
1048 * In TLSv1.3 we've already negotiated our cipher so we do this call now.
1049 * For < TLSv1.3 we defer it until after cipher negotiation.
1051 * On failure SSLfatal() already called.
1053 return tls_handle_alpn(s);
1056 static int init_sig_algs(SSL *s, unsigned int context)
1058 /* Clear any signature algorithms extension received */
1059 OPENSSL_free(s->s3->tmp.peer_sigalgs);
1060 s->s3->tmp.peer_sigalgs = NULL;
1065 #ifndef OPENSSL_NO_SRP
1066 static int init_srp(SSL *s, unsigned int context)
1068 OPENSSL_free(s->srp_ctx.login);
1069 s->srp_ctx.login = NULL;
1075 static int init_etm(SSL *s, unsigned int context)
1082 static int init_ems(SSL *s, unsigned int context)
1085 s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS;
1090 static int final_ems(SSL *s, unsigned int context, int sent)
1092 if (!s->server && s->hit) {
1094 * Check extended master secret extension is consistent with
1097 if (!(s->s3->flags & TLS1_FLAGS_RECEIVED_EXTMS) !=
1098 !(s->session->flags & SSL_SESS_FLAG_EXTMS)) {
1099 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_FINAL_EMS,
1100 SSL_R_INCONSISTENT_EXTMS);
1108 static int init_certificate_authorities(SSL *s, unsigned int context)
1110 sk_X509_NAME_pop_free(s->s3->tmp.peer_ca_names, X509_NAME_free);
1111 s->s3->tmp.peer_ca_names = NULL;
1115 static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
1116 unsigned int context,
1120 const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s);
1122 if (ca_sk == NULL || sk_X509_NAME_num(ca_sk) == 0)
1123 return EXT_RETURN_NOT_SENT;
1125 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_certificate_authorities)
1126 || !WPACKET_start_sub_packet_u16(pkt)) {
1127 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1128 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES,
1129 ERR_R_INTERNAL_ERROR);
1130 return EXT_RETURN_FAIL;
1133 if (!construct_ca_names(s, pkt)) {
1134 /* SSLfatal() already called */
1135 return EXT_RETURN_FAIL;
1138 if (!WPACKET_close(pkt)) {
1139 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1140 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES,
1141 ERR_R_INTERNAL_ERROR);
1142 return EXT_RETURN_FAIL;
1145 return EXT_RETURN_SENT;
1148 static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt,
1149 unsigned int context, X509 *x,
1152 if (!parse_ca_names(s, pkt))
1154 if (PACKET_remaining(pkt) != 0) {
1155 SSLfatal(s, SSL_AD_DECODE_ERROR,
1156 SSL_F_TLS_PARSE_CERTIFICATE_AUTHORITIES, SSL_R_BAD_EXTENSION);
1162 #ifndef OPENSSL_NO_SRTP
1163 static int init_srtp(SSL *s, unsigned int context)
1166 s->srtp_profile = NULL;
1172 static int final_sig_algs(SSL *s, unsigned int context, int sent)
1174 if (!sent && SSL_IS_TLS13(s) && !s->hit) {
1175 SSLfatal(s, TLS13_AD_MISSING_EXTENSION, SSL_F_FINAL_SIG_ALGS,
1176 SSL_R_MISSING_SIGALGS_EXTENSION);
1183 #ifndef OPENSSL_NO_EC
1184 static int final_key_share(SSL *s, unsigned int context, int sent)
1186 if (!SSL_IS_TLS13(s))
1189 /* Nothing to do for key_share in an HRR */
1190 if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0)
1197 * we have no key_share
1199 * (we are not resuming
1200 * OR the kex_mode doesn't allow non key_share resumes)
1207 || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0)) {
1208 /* Nothing left we can do - just fail */
1209 SSLfatal(s, SSL_AD_MISSING_EXTENSION, SSL_F_FINAL_KEY_SHARE,
1210 SSL_R_NO_SUITABLE_KEY_SHARE);
1217 * we have no key_share
1220 * we didn't already send a HelloRetryRequest
1222 * the client sent a key_share extension
1224 * (we are not resuming
1225 * OR the kex_mode allows key_share resumes)
1227 * a shared group exists
1229 * send a HelloRetryRequest
1231 * we are not resuming
1233 * the kex_mode doesn't allow non key_share resumes
1237 if (s->server && s->s3->peer_tmp == NULL) {
1238 /* No suitable share */
1239 if (s->hello_retry_request == SSL_HRR_NONE && sent
1241 || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE)
1243 const uint16_t *pgroups, *clntgroups;
1244 size_t num_groups, clnt_num_groups, i;
1245 unsigned int group_id = 0;
1247 /* Check if a shared group exists */
1249 /* Get the clients list of supported groups. */
1250 tls1_get_peer_groups(s, &clntgroups, &clnt_num_groups);
1251 tls1_get_supported_groups(s, &pgroups, &num_groups);
1253 /* Find the first group we allow that is also in client's list */
1254 for (i = 0; i < num_groups; i++) {
1255 group_id = pgroups[i];
1257 if (check_in_list(s, group_id, clntgroups, clnt_num_groups, 1))
1261 if (i < num_groups) {
1262 /* A shared group exists so send a HelloRetryRequest */
1263 s->s3->group_id = group_id;
1264 s->hello_retry_request = SSL_HRR_PENDING;
1269 || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0) {
1270 /* Nothing left we can do - just fail */
1272 sent ? SSL_AD_HANDSHAKE_FAILURE : SSL_AD_MISSING_EXTENSION,
1273 SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE);
1278 /* We have a key_share so don't send any more HelloRetryRequest messages */
1279 if (s->server && s->hello_retry_request == SSL_HRR_PENDING)
1280 s->hello_retry_request = SSL_HRR_COMPLETE;
1283 * For a client side resumption with no key_share we need to generate
1284 * the handshake secret (otherwise this is done during key_share
1287 if (!sent && !s->server && !tls13_generate_handshake_secret(s, NULL, 0)) {
1288 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_KEY_SHARE,
1289 ERR_R_INTERNAL_ERROR);
1297 static int init_psk_kex_modes(SSL *s, unsigned int context)
1299 s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_NONE;
1303 int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart,
1304 size_t binderoffset, const unsigned char *binderin,
1305 unsigned char *binderout, SSL_SESSION *sess, int sign,
1308 EVP_PKEY *mackey = NULL;
1309 EVP_MD_CTX *mctx = NULL;
1310 unsigned char hash[EVP_MAX_MD_SIZE], binderkey[EVP_MAX_MD_SIZE];
1311 unsigned char finishedkey[EVP_MAX_MD_SIZE], tmpbinder[EVP_MAX_MD_SIZE];
1312 unsigned char tmppsk[EVP_MAX_MD_SIZE];
1313 unsigned char *early_secret, *psk;
1314 const char resumption_label[] = "res binder";
1315 const char external_label[] = "ext binder";
1316 const char nonce_label[] = "resumption";
1318 size_t bindersize, labelsize, hashsize = EVP_MD_size(md);
1320 int usepskfored = 0;
1323 && s->early_data_state == SSL_EARLY_DATA_CONNECTING
1324 && s->session->ext.max_early_data == 0
1325 && sess->ext.max_early_data > 0)
1329 label = external_label;
1330 labelsize = sizeof(external_label) - 1;
1332 label = resumption_label;
1333 labelsize = sizeof(resumption_label) - 1;
1336 if (sess->master_key_length != hashsize) {
1337 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1343 psk = sess->master_key;
1346 if (!tls13_hkdf_expand(s, md, sess->master_key,
1347 (const unsigned char *)nonce_label,
1348 sizeof(nonce_label) - 1, sess->ext.tick_nonce,
1349 sess->ext.tick_nonce_len, psk, hashsize)) {
1350 /* SSLfatal() already called */
1356 * Generate the early_secret. On the server side we've selected a PSK to
1357 * resume with (internal or external) so we always do this. On the client
1358 * side we do this for a non-external (i.e. resumption) PSK or external PSK
1359 * that will be used for early_data so that it is in place for sending early
1360 * data. For client side external PSK not being used for early_data we
1361 * generate it but store it away for later use.
1363 if (s->server || !external || usepskfored)
1364 early_secret = (unsigned char *)s->early_secret;
1366 early_secret = (unsigned char *)sess->early_secret;
1367 if (!tls13_generate_secret(s, md, NULL, psk, hashsize, early_secret)) {
1368 /* SSLfatal() already called */
1373 * Create the handshake hash for the binder key...the messages so far are
1376 mctx = EVP_MD_CTX_new();
1378 || EVP_DigestInit_ex(mctx, md, NULL) <= 0
1379 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
1380 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1381 ERR_R_INTERNAL_ERROR);
1385 /* Generate the binder key */
1386 if (!tls13_hkdf_expand(s, md, early_secret, (unsigned char *)label,
1387 labelsize, hash, hashsize, binderkey, hashsize)) {
1388 /* SSLfatal() already called */
1392 /* Generate the finished key */
1393 if (!tls13_derive_finishedkey(s, md, binderkey, finishedkey, hashsize)) {
1394 /* SSLfatal() already called */
1398 if (EVP_DigestInit_ex(mctx, md, NULL) <= 0) {
1399 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1400 ERR_R_INTERNAL_ERROR);
1405 * Get a hash of the ClientHello up to the start of the binders. If we are
1406 * following a HelloRetryRequest then this includes the hash of the first
1407 * ClientHello and the HelloRetryRequest itself.
1409 if (s->hello_retry_request == SSL_HRR_PENDING) {
1413 hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
1414 if (hdatalen <= 0) {
1415 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1416 SSL_R_BAD_HANDSHAKE_LENGTH);
1421 * For servers the handshake buffer data will include the second
1422 * ClientHello - which we don't want - so we need to take that bit off.
1425 PACKET hashprefix, msg;
1427 /* Find how many bytes are left after the first two messages */
1428 if (!PACKET_buf_init(&hashprefix, hdata, hdatalen)
1429 || !PACKET_forward(&hashprefix, 1)
1430 || !PACKET_get_length_prefixed_3(&hashprefix, &msg)
1431 || !PACKET_forward(&hashprefix, 1)
1432 || !PACKET_get_length_prefixed_3(&hashprefix, &msg)) {
1433 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1434 ERR_R_INTERNAL_ERROR);
1437 hdatalen -= PACKET_remaining(&hashprefix);
1440 if (EVP_DigestUpdate(mctx, hdata, hdatalen) <= 0) {
1441 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1442 ERR_R_INTERNAL_ERROR);
1447 if (EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0
1448 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
1449 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1450 ERR_R_INTERNAL_ERROR);
1454 mackey = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, finishedkey, hashsize);
1455 if (mackey == NULL) {
1456 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1457 ERR_R_INTERNAL_ERROR);
1462 binderout = tmpbinder;
1464 bindersize = hashsize;
1465 if (EVP_DigestSignInit(mctx, NULL, md, NULL, mackey) <= 0
1466 || EVP_DigestSignUpdate(mctx, hash, hashsize) <= 0
1467 || EVP_DigestSignFinal(mctx, binderout, &bindersize) <= 0
1468 || bindersize != hashsize) {
1469 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1470 ERR_R_INTERNAL_ERROR);
1477 /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */
1478 ret = (CRYPTO_memcmp(binderin, binderout, hashsize) == 0);
1480 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PSK_DO_BINDER,
1481 SSL_R_BINDER_DOES_NOT_VERIFY);
1485 OPENSSL_cleanse(binderkey, sizeof(binderkey));
1486 OPENSSL_cleanse(finishedkey, sizeof(finishedkey));
1487 EVP_PKEY_free(mackey);
1488 EVP_MD_CTX_free(mctx);
1493 static int final_early_data(SSL *s, unsigned int context, int sent)
1499 if (context == SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
1501 && !s->ext.early_data_ok) {
1503 * If we get here then the server accepted our early_data but we
1504 * later realised that it shouldn't have done (e.g. inconsistent
1507 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_FINAL_EARLY_DATA,
1508 SSL_R_BAD_EARLY_DATA);
1515 if (s->max_early_data == 0
1517 || s->session->ext.tick_identity != 0
1518 || s->early_data_state != SSL_EARLY_DATA_ACCEPTING
1519 || !s->ext.early_data_ok
1520 || s->hello_retry_request != SSL_HRR_NONE) {
1521 s->ext.early_data = SSL_EARLY_DATA_REJECTED;
1523 s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
1525 if (!tls13_change_cipher_state(s,
1526 SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_SERVER_READ)) {
1527 /* SSLfatal() already called */
1535 static int final_maxfragmentlen(SSL *s, unsigned int context, int sent)
1538 * Session resumption on server-side with MFL extension active
1539 * BUT MFL extension packet was not resent (i.e. sent == 0)
1541 if (s->server && s->hit && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
1543 SSLfatal(s, SSL_AD_MISSING_EXTENSION, SSL_F_FINAL_MAXFRAGMENTLEN,
1544 SSL_R_BAD_EXTENSION);
1548 /* Current SSL buffer is lower than requested MFL */
1549 if (s->session && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
1550 && s->max_send_fragment < GET_MAX_FRAGMENT_LENGTH(s->session))
1551 /* trigger a larger buffer reallocation */
1552 if (!ssl3_setup_buffers(s)) {
1553 /* SSLfatal() already called */