2 * Copyright 2016-2018 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"
15 #include "internal/cryptlib.h"
17 static int final_renegotiate(SSL *s, unsigned int context, int sent);
18 static int init_server_name(SSL *s, unsigned int context);
19 static int final_server_name(SSL *s, unsigned int context, int sent);
21 static int final_ec_pt_formats(SSL *s, unsigned int context, int sent);
23 static int init_session_ticket(SSL *s, unsigned int context);
24 #ifndef OPENSSL_NO_OCSP
25 static int init_status_request(SSL *s, unsigned int context);
27 #ifndef OPENSSL_NO_NEXTPROTONEG
28 static int init_npn(SSL *s, unsigned int context);
30 static int init_alpn(SSL *s, unsigned int context);
31 static int final_alpn(SSL *s, unsigned int context, int sent);
32 static int init_sig_algs(SSL *s, unsigned int context);
33 static int init_certificate_authorities(SSL *s, unsigned int context);
34 static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
38 static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt,
39 unsigned int context, X509 *x,
41 #ifndef OPENSSL_NO_SRP
42 static int init_srp(SSL *s, unsigned int context);
44 static int init_etm(SSL *s, unsigned int context);
45 static int init_ems(SSL *s, unsigned int context);
46 static int final_ems(SSL *s, unsigned int context, int sent);
47 static int init_psk_kex_modes(SSL *s, unsigned int context);
49 static int final_key_share(SSL *s, unsigned int context, int sent);
51 #ifndef OPENSSL_NO_SRTP
52 static int init_srtp(SSL *s, unsigned int context);
54 static int final_sig_algs(SSL *s, unsigned int context, int sent);
55 static int final_early_data(SSL *s, unsigned int context, int sent);
56 static int final_maxfragmentlen(SSL *s, unsigned int context, int sent);
58 /* Structure to define a built-in extension */
59 typedef struct extensions_definition_st {
60 /* The defined type for the extension */
63 * The context that this extension applies to, e.g. what messages and
68 * Initialise extension before parsing. Always called for relevant contexts
69 * even if extension not present
71 int (*init)(SSL *s, unsigned int context);
72 /* Parse extension sent from client to server */
73 int (*parse_ctos)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
75 /* Parse extension send from server to client */
76 int (*parse_stoc)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
78 /* Construct extension sent from server to client */
79 EXT_RETURN (*construct_stoc)(SSL *s, WPACKET *pkt, unsigned int context,
80 X509 *x, size_t chainidx);
81 /* Construct extension sent from client to server */
82 EXT_RETURN (*construct_ctos)(SSL *s, WPACKET *pkt, unsigned int context,
83 X509 *x, size_t chainidx);
85 * Finalise extension after parsing. Always called where an extensions was
86 * initialised even if the extension was not present. |sent| is set to 1 if
87 * the extension was seen, or 0 otherwise.
89 int (*final)(SSL *s, unsigned int context, int sent);
90 } EXTENSION_DEFINITION;
93 * Definitions of all built-in extensions. NOTE: Changes in the number or order
94 * of these extensions should be mirrored with equivalent changes to the
95 * indexes ( TLSEXT_IDX_* ) defined in ssl_locl.h.
96 * Each extension has an initialiser, a client and
97 * server side parser and a finaliser. The initialiser is called (if the
98 * extension is relevant to the given context) even if we did not see the
99 * extension in the message that we received. The parser functions are only
100 * called if we see the extension in the message. The finalisers are always
101 * called if the initialiser was called.
102 * There are also server and client side constructor functions which are always
103 * called during message construction if the extension is relevant for the
105 * The initialisation, parsing, finalisation and construction functions are
106 * always called in the order defined in this list. Some extensions may depend
107 * on others having been processed first, so the order of this list is
109 * The extension context is defined by a series of flags which specify which
110 * messages the extension is relevant to. These flags also specify whether the
111 * extension is relevant to a particular protocol or protocol version.
113 * TODO(TLS1.3): Make sure we have a test to check the consistency of these
115 * NOTE: WebSphere Application Server 7+ cannot handle empty extensions at
116 * the end, keep these extensions before signature_algorithm.
118 #define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL }
119 static const EXTENSION_DEFINITION ext_defs[] = {
121 TLSEXT_TYPE_renegotiate,
122 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
123 | SSL_EXT_SSL3_ALLOWED | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
124 NULL, tls_parse_ctos_renegotiate, tls_parse_stoc_renegotiate,
125 tls_construct_stoc_renegotiate, tls_construct_ctos_renegotiate,
129 TLSEXT_TYPE_server_name,
130 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
131 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
133 tls_parse_ctos_server_name, tls_parse_stoc_server_name,
134 tls_construct_stoc_server_name, tls_construct_ctos_server_name,
138 TLSEXT_TYPE_max_fragment_length,
139 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
140 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
141 NULL, tls_parse_ctos_maxfragmentlen, tls_parse_stoc_maxfragmentlen,
142 tls_construct_stoc_maxfragmentlen, tls_construct_ctos_maxfragmentlen,
145 #ifndef OPENSSL_NO_SRP
148 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
149 init_srp, tls_parse_ctos_srp, NULL, NULL, tls_construct_ctos_srp, NULL
154 #ifndef OPENSSL_NO_EC
156 TLSEXT_TYPE_ec_point_formats,
157 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
158 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
159 NULL, tls_parse_ctos_ec_pt_formats, tls_parse_stoc_ec_pt_formats,
160 tls_construct_stoc_ec_pt_formats, tls_construct_ctos_ec_pt_formats,
165 * "supported_groups" is spread across several specifications.
166 * It was originally specified as "elliptic_curves" in RFC 4492,
167 * and broadened to include named FFDH groups by RFC 7919.
168 * Both RFCs 4492 and 7919 do not include a provision for the server
169 * to indicate to the client the complete list of groups supported
170 * by the server, with the server instead just indicating the
171 * selected group for this connection in the ServerKeyExchange
172 * message. TLS 1.3 adds a scheme for the server to indicate
173 * to the client its list of supported groups in the
174 * EncryptedExtensions message, but none of the relevant
175 * specifications permit sending supported_groups in the ServerHello.
176 * Nonetheless (possibly due to the close proximity to the
177 * "ec_point_formats" extension, which is allowed in the ServerHello),
178 * there are several servers that send this extension in the
179 * ServerHello anyway. Up to and including the 1.1.0 release,
180 * we did not check for the presence of nonpermitted extensions,
181 * so to avoid a regression, we must permit this extension in the
182 * TLS 1.2 ServerHello as well.
184 * Note that there is no tls_parse_stoc_supported_groups function,
185 * so we do not perform any additional parsing, validation, or
186 * processing on the server's group list -- this is just a minimal
187 * change to preserve compatibility with these misbehaving servers.
189 TLSEXT_TYPE_supported_groups,
190 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
191 | SSL_EXT_TLS1_2_SERVER_HELLO,
192 NULL, tls_parse_ctos_supported_groups, NULL,
193 tls_construct_stoc_supported_groups,
194 tls_construct_ctos_supported_groups, NULL
201 TLSEXT_TYPE_session_ticket,
202 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
203 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
204 init_session_ticket, tls_parse_ctos_session_ticket,
205 tls_parse_stoc_session_ticket, tls_construct_stoc_session_ticket,
206 tls_construct_ctos_session_ticket, NULL
208 #ifndef OPENSSL_NO_OCSP
210 TLSEXT_TYPE_status_request,
211 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
212 | SSL_EXT_TLS1_3_CERTIFICATE,
213 init_status_request, tls_parse_ctos_status_request,
214 tls_parse_stoc_status_request, tls_construct_stoc_status_request,
215 tls_construct_ctos_status_request, NULL
220 #ifndef OPENSSL_NO_NEXTPROTONEG
222 TLSEXT_TYPE_next_proto_neg,
223 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
224 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
225 init_npn, tls_parse_ctos_npn, tls_parse_stoc_npn,
226 tls_construct_stoc_next_proto_neg, tls_construct_ctos_npn, NULL
233 * Must appear in this list after server_name so that finalisation
234 * happens after server_name callbacks
236 TLSEXT_TYPE_application_layer_protocol_negotiation,
237 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
238 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
239 init_alpn, tls_parse_ctos_alpn, tls_parse_stoc_alpn,
240 tls_construct_stoc_alpn, tls_construct_ctos_alpn, final_alpn
242 #ifndef OPENSSL_NO_SRTP
244 TLSEXT_TYPE_use_srtp,
245 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
246 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS | SSL_EXT_DTLS_ONLY,
247 init_srtp, tls_parse_ctos_use_srtp, tls_parse_stoc_use_srtp,
248 tls_construct_stoc_use_srtp, tls_construct_ctos_use_srtp, NULL
254 TLSEXT_TYPE_encrypt_then_mac,
255 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
256 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
257 init_etm, tls_parse_ctos_etm, tls_parse_stoc_etm,
258 tls_construct_stoc_etm, tls_construct_ctos_etm, NULL
260 #ifndef OPENSSL_NO_CT
262 TLSEXT_TYPE_signed_certificate_timestamp,
263 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
264 | SSL_EXT_TLS1_3_CERTIFICATE,
267 * No server side support for this, but can be provided by a custom
268 * extension. This is an exception to the rule that custom extensions
269 * cannot override built in ones.
271 NULL, tls_parse_stoc_sct, NULL, tls_construct_ctos_sct, NULL
277 TLSEXT_TYPE_extended_master_secret,
278 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
279 | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
280 init_ems, tls_parse_ctos_ems, tls_parse_stoc_ems,
281 tls_construct_stoc_ems, tls_construct_ctos_ems, final_ems
284 TLSEXT_TYPE_signature_algorithms,
285 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
286 init_sig_algs, tls_parse_ctos_sig_algs,
287 tls_parse_ctos_sig_algs, tls_construct_ctos_sig_algs,
288 tls_construct_ctos_sig_algs, final_sig_algs
291 TLSEXT_TYPE_supported_versions,
292 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
293 | SSL_EXT_TLS1_3_SERVER_HELLO | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
294 | SSL_EXT_TLS_IMPLEMENTATION_ONLY,
296 /* Processed inline as part of version selection */
297 NULL, tls_parse_stoc_supported_versions,
298 tls_construct_stoc_supported_versions,
299 tls_construct_ctos_supported_versions, NULL
302 TLSEXT_TYPE_psk_kex_modes,
303 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS_IMPLEMENTATION_ONLY
304 | SSL_EXT_TLS1_3_ONLY,
305 init_psk_kex_modes, tls_parse_ctos_psk_kex_modes, NULL, NULL,
306 tls_construct_ctos_psk_kex_modes, NULL
308 #ifndef OPENSSL_NO_EC
311 * Must be in this list after supported_groups. We need that to have
312 * been parsed before we do this one.
314 TLSEXT_TYPE_key_share,
315 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO
316 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST | SSL_EXT_TLS_IMPLEMENTATION_ONLY
317 | SSL_EXT_TLS1_3_ONLY,
318 NULL, tls_parse_ctos_key_share, tls_parse_stoc_key_share,
319 tls_construct_stoc_key_share, tls_construct_ctos_key_share,
324 /* Must be after key_share */
326 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
327 | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
328 NULL, tls_parse_ctos_cookie, tls_parse_stoc_cookie,
329 tls_construct_stoc_cookie, tls_construct_ctos_cookie, NULL
333 * Special unsolicited ServerHello extension only used when
334 * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set
336 TLSEXT_TYPE_cryptopro_bug,
337 SSL_EXT_TLS1_2_SERVER_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
338 NULL, NULL, NULL, tls_construct_stoc_cryptopro_bug, NULL, NULL
341 TLSEXT_TYPE_early_data,
342 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
343 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
344 NULL, tls_parse_ctos_early_data, tls_parse_stoc_early_data,
345 tls_construct_stoc_early_data, tls_construct_ctos_early_data,
349 TLSEXT_TYPE_certificate_authorities,
350 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
351 | SSL_EXT_TLS1_3_ONLY,
352 init_certificate_authorities,
353 tls_parse_certificate_authorities, tls_parse_certificate_authorities,
354 tls_construct_certificate_authorities,
355 tls_construct_certificate_authorities, NULL,
358 /* Must be immediately before pre_shared_key */
360 SSL_EXT_CLIENT_HELLO,
362 /* We send this, but don't read it */
363 NULL, NULL, NULL, tls_construct_ctos_padding, NULL
366 /* Required by the TLSv1.3 spec to always be the last extension */
368 SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO
369 | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
370 NULL, tls_parse_ctos_psk, tls_parse_stoc_psk, tls_construct_stoc_psk,
371 tls_construct_ctos_psk, NULL
375 /* Check whether an extension's context matches the current context */
376 static int validate_context(SSL *s, unsigned int extctx, unsigned int thisctx)
378 /* Check we're allowed to use this extension in this context */
379 if ((thisctx & extctx) == 0)
382 if (SSL_IS_DTLS(s)) {
383 if ((extctx & SSL_EXT_TLS_ONLY) != 0)
385 } else if ((extctx & SSL_EXT_DTLS_ONLY) != 0) {
392 int tls_validate_all_contexts(SSL *s, unsigned int thisctx, RAW_EXTENSION *exts)
394 size_t i, num_exts, builtin_num = OSSL_NELEM(ext_defs), offset;
395 RAW_EXTENSION *thisext;
396 unsigned int context;
397 ENDPOINT role = ENDPOINT_BOTH;
399 if ((thisctx & SSL_EXT_CLIENT_HELLO) != 0)
400 role = ENDPOINT_SERVER;
401 else if ((thisctx & SSL_EXT_TLS1_2_SERVER_HELLO) != 0)
402 role = ENDPOINT_CLIENT;
404 /* Calculate the number of extensions in the extensions list */
405 num_exts = builtin_num + s->cert->custext.meths_count;
407 for (thisext = exts, i = 0; i < num_exts; i++, thisext++) {
408 if (!thisext->present)
411 if (i < builtin_num) {
412 context = ext_defs[i].context;
414 custom_ext_method *meth = NULL;
416 meth = custom_ext_find(&s->cert->custext, role, thisext->type,
418 if (!ossl_assert(meth != NULL))
420 context = meth->context;
423 if (!validate_context(s, context, thisctx))
431 * Verify whether we are allowed to use the extension |type| in the current
432 * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to
433 * indicate the extension is not allowed. If returning 1 then |*found| is set to
434 * the definition for the extension we found.
436 static int verify_extension(SSL *s, unsigned int context, unsigned int type,
437 custom_ext_methods *meths, RAW_EXTENSION *rawexlist,
438 RAW_EXTENSION **found)
441 size_t builtin_num = OSSL_NELEM(ext_defs);
442 const EXTENSION_DEFINITION *thisext;
444 for (i = 0, thisext = ext_defs; i < builtin_num; i++, thisext++) {
445 if (type == thisext->type) {
446 if (!validate_context(s, thisext->context, context))
449 *found = &rawexlist[i];
454 /* Check the custom extensions */
457 ENDPOINT role = ENDPOINT_BOTH;
458 custom_ext_method *meth = NULL;
460 if ((context & SSL_EXT_CLIENT_HELLO) != 0)
461 role = ENDPOINT_SERVER;
462 else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0)
463 role = ENDPOINT_CLIENT;
465 meth = custom_ext_find(meths, role, type, &offset);
467 if (!validate_context(s, meth->context, context))
469 *found = &rawexlist[offset + builtin_num];
474 /* Unknown extension. We allow it */
480 * Check whether the context defined for an extension |extctx| means whether
481 * the extension is relevant for the current context |thisctx| or not. Returns
482 * 1 if the extension is relevant for this context, and 0 otherwise
484 int extension_is_relevant(SSL *s, unsigned int extctx, unsigned int thisctx)
489 * For HRR we haven't selected the version yet but we know it will be
492 if ((thisctx & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0)
495 is_tls13 = SSL_IS_TLS13(s);
498 && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0)
499 || (s->version == SSL3_VERSION
500 && (extctx & SSL_EXT_SSL3_ALLOWED) == 0)
501 || (is_tls13 && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0)
502 || (!is_tls13 && (extctx & SSL_EXT_TLS1_3_ONLY) != 0)
503 || (s->hit && (extctx & SSL_EXT_IGNORE_ON_RESUMPTION) != 0))
510 * Gather a list of all the extensions from the data in |packet]. |context|
511 * tells us which message this extension is for. The raw extension data is
512 * stored in |*res| on success. We don't actually process the content of the
513 * extensions yet, except to check their types. This function also runs the
514 * initialiser functions for all known extensions if |init| is nonzero (whether
515 * we have collected them or not). If successful the caller is responsible for
516 * freeing the contents of |*res|.
518 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
519 * more than one extension of the same type in a ClientHello or ServerHello.
520 * This function returns 1 if all extensions are unique and we have parsed their
521 * types, and 0 if the extensions contain duplicates, could not be successfully
522 * found, or an internal error occurred. We only check duplicates for
523 * extensions that we know about. We ignore others.
525 int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context,
526 RAW_EXTENSION **res, size_t *len, int init)
528 PACKET extensions = *packet;
531 custom_ext_methods *exts = &s->cert->custext;
532 RAW_EXTENSION *raw_extensions = NULL;
533 const EXTENSION_DEFINITION *thisexd;
538 * Initialise server side custom extensions. Client side is done during
539 * construction of extensions for the ClientHello.
541 if ((context & SSL_EXT_CLIENT_HELLO) != 0)
542 custom_ext_init(&s->cert->custext);
544 num_exts = OSSL_NELEM(ext_defs) + (exts != NULL ? exts->meths_count : 0);
545 raw_extensions = OPENSSL_zalloc(num_exts * sizeof(*raw_extensions));
546 if (raw_extensions == NULL) {
547 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_COLLECT_EXTENSIONS,
548 ERR_R_MALLOC_FAILURE);
553 while (PACKET_remaining(&extensions) > 0) {
554 unsigned int type, idx;
556 RAW_EXTENSION *thisex;
558 if (!PACKET_get_net_2(&extensions, &type) ||
559 !PACKET_get_length_prefixed_2(&extensions, &extension)) {
560 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_COLLECT_EXTENSIONS,
561 SSL_R_BAD_EXTENSION);
565 * Verify this extension is allowed. We only check duplicates for
566 * extensions that we recognise. We also have a special case for the
567 * PSK extension, which must be the last one in the ClientHello.
569 if (!verify_extension(s, context, type, exts, raw_extensions, &thisex)
570 || (thisex != NULL && thisex->present == 1)
571 || (type == TLSEXT_TYPE_psk
572 && (context & SSL_EXT_CLIENT_HELLO) != 0
573 && PACKET_remaining(&extensions) != 0)) {
574 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_COLLECT_EXTENSIONS,
575 SSL_R_BAD_EXTENSION);
578 idx = thisex - raw_extensions;
580 * Check that we requested this extension (if appropriate). Requests can
581 * be sent in the ClientHello and CertificateRequest. Unsolicited
582 * extensions can be sent in the NewSessionTicket. We only do this for
583 * the built-in extensions. Custom extensions have a different but
584 * similar check elsewhere.
586 * - The HRR cookie extension is unsolicited
587 * - The renegotiate extension is unsolicited (the client signals
588 * support via an SCSV)
589 * - The signed_certificate_timestamp extension can be provided by a
590 * custom extension or by the built-in version. We let the extension
591 * itself handle unsolicited response checks.
593 if (idx < OSSL_NELEM(ext_defs)
594 && (context & (SSL_EXT_CLIENT_HELLO
595 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
596 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) == 0
597 && type != TLSEXT_TYPE_cookie
598 && type != TLSEXT_TYPE_renegotiate
599 && type != TLSEXT_TYPE_signed_certificate_timestamp
600 && (s->ext.extflags[idx] & SSL_EXT_FLAG_SENT) == 0) {
601 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION,
602 SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_UNSOLICITED_EXTENSION);
605 if (thisex != NULL) {
606 thisex->data = extension;
609 thisex->received_order = i++;
611 s->ext.debug_cb(s, !s->server, thisex->type,
612 PACKET_data(&thisex->data),
613 PACKET_remaining(&thisex->data),
620 * Initialise all known extensions relevant to this context,
621 * whether we have found them or not
623 for (thisexd = ext_defs, i = 0; i < OSSL_NELEM(ext_defs);
625 if (thisexd->init != NULL && (thisexd->context & context) != 0
626 && extension_is_relevant(s, thisexd->context, context)
627 && !thisexd->init(s, context)) {
628 /* SSLfatal() already called */
634 *res = raw_extensions;
640 OPENSSL_free(raw_extensions);
645 * Runs the parser for a given extension with index |idx|. |exts| contains the
646 * list of all parsed extensions previously collected by
647 * tls_collect_extensions(). The parser is only run if it is applicable for the
648 * given |context| and the parser has not already been run. If this is for a
649 * Certificate message, then we also provide the parser with the relevant
650 * Certificate |x| and its position in the |chainidx| with 0 being the first
651 * Certificate. Returns 1 on success or 0 on failure. If an extension is not
652 * present this counted as success.
654 int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context,
655 RAW_EXTENSION *exts, X509 *x, size_t chainidx)
657 RAW_EXTENSION *currext = &exts[idx];
658 int (*parser)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
659 size_t chainidx) = NULL;
661 /* Skip if the extension is not present */
662 if (!currext->present)
665 /* Skip if we've already parsed this extension */
671 if (idx < OSSL_NELEM(ext_defs)) {
672 /* We are handling a built-in extension */
673 const EXTENSION_DEFINITION *extdef = &ext_defs[idx];
675 /* Check if extension is defined for our protocol. If not, skip */
676 if (!extension_is_relevant(s, extdef->context, context))
679 parser = s->server ? extdef->parse_ctos : extdef->parse_stoc;
682 return parser(s, &currext->data, context, x, chainidx);
685 * If the parser is NULL we fall through to the custom extension
690 /* Parse custom extensions */
691 return custom_ext_parse(s, context, currext->type,
692 PACKET_data(&currext->data),
693 PACKET_remaining(&currext->data),
698 * Parse all remaining extensions that have not yet been parsed. Also calls the
699 * finalisation for all extensions at the end if |fin| is nonzero, whether we
700 * collected them or not. Returns 1 for success or 0 for failure. If we are
701 * working on a Certificate message then we also pass the Certificate |x| and
702 * its position in the |chainidx|, with 0 being the first certificate.
704 int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, X509 *x,
705 size_t chainidx, int fin)
707 size_t i, numexts = OSSL_NELEM(ext_defs);
708 const EXTENSION_DEFINITION *thisexd;
710 /* Calculate the number of extensions in the extensions list */
711 numexts += s->cert->custext.meths_count;
713 /* Parse each extension in turn */
714 for (i = 0; i < numexts; i++) {
715 if (!tls_parse_extension(s, i, context, exts, x, chainidx)) {
716 /* SSLfatal() already called */
723 * Finalise all known extensions relevant to this context,
724 * whether we have found them or not
726 for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs);
728 if (thisexd->final != NULL && (thisexd->context & context) != 0
729 && !thisexd->final(s, context, exts[i].present)) {
730 /* SSLfatal() already called */
739 int should_add_extension(SSL *s, unsigned int extctx, unsigned int thisctx,
742 /* Skip if not relevant for our context */
743 if ((extctx & thisctx) == 0)
746 /* Check if this extension is defined for our protocol. If not, skip */
747 if ((SSL_IS_DTLS(s) && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0)
748 || (s->version == SSL3_VERSION
749 && (extctx & SSL_EXT_SSL3_ALLOWED) == 0)
751 && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0)
753 && (extctx & SSL_EXT_TLS1_3_ONLY) != 0
754 && (thisctx & SSL_EXT_CLIENT_HELLO) == 0)
755 || ((extctx & SSL_EXT_TLS1_3_ONLY) != 0
756 && (thisctx & SSL_EXT_CLIENT_HELLO) != 0
757 && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION)))
764 * Construct all the extensions relevant to the current |context| and write
765 * them to |pkt|. If this is an extension for a Certificate in a Certificate
766 * message, then |x| will be set to the Certificate we are handling, and
767 * |chainidx| will indicate the position in the chainidx we are processing (with
768 * 0 being the first in the chain). Returns 1 on success or 0 on failure. On a
769 * failure construction stops at the first extension to fail to construct.
771 int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context,
772 X509 *x, size_t chainidx)
775 int min_version, max_version = 0, reason;
776 const EXTENSION_DEFINITION *thisexd;
778 if (!WPACKET_start_sub_packet_u16(pkt)
780 * If extensions are of zero length then we don't even add the
781 * extensions length bytes to a ClientHello/ServerHello
785 (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) != 0
786 && !WPACKET_set_flags(pkt,
787 WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH))) {
788 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_EXTENSIONS,
789 ERR_R_INTERNAL_ERROR);
793 if ((context & SSL_EXT_CLIENT_HELLO) != 0) {
794 reason = ssl_get_min_max_version(s, &min_version, &max_version);
796 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_EXTENSIONS,
802 /* Add custom extensions first */
803 if ((context & SSL_EXT_CLIENT_HELLO) != 0) {
804 /* On the server side with initialise during ClientHello parsing */
805 custom_ext_init(&s->cert->custext);
807 if (!custom_ext_add(s, context, pkt, x, chainidx, max_version)) {
808 /* SSLfatal() already called */
812 for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) {
813 EXT_RETURN (*construct)(SSL *s, WPACKET *pkt, unsigned int context,
814 X509 *x, size_t chainidx);
817 /* Skip if not relevant for our context */
818 if (!should_add_extension(s, thisexd->context, context, max_version))
821 construct = s->server ? thisexd->construct_stoc
822 : thisexd->construct_ctos;
824 if (construct == NULL)
827 ret = construct(s, pkt, context, x, chainidx);
828 if (ret == EXT_RETURN_FAIL) {
829 /* SSLfatal() already called */
832 if (ret == EXT_RETURN_SENT
833 && (context & (SSL_EXT_CLIENT_HELLO
834 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
835 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) != 0)
836 s->ext.extflags[i] |= SSL_EXT_FLAG_SENT;
839 if (!WPACKET_close(pkt)) {
840 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_CONSTRUCT_EXTENSIONS,
841 ERR_R_INTERNAL_ERROR);
849 * Built in extension finalisation and initialisation functions. All initialise
850 * or finalise the associated extension type for the given |context|. For
851 * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
852 * otherwise. These functions return 1 on success or 0 on failure.
855 static int final_renegotiate(SSL *s, unsigned int context, int sent)
859 * Check if we can connect to a server that doesn't support safe
862 if (!(s->options & SSL_OP_LEGACY_SERVER_CONNECT)
863 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
865 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_FINAL_RENEGOTIATE,
866 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
873 /* Need RI if renegotiating */
875 && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
877 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_FINAL_RENEGOTIATE,
878 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
886 static int init_server_name(SSL *s, unsigned int context)
889 s->servername_done = 0;
894 static int final_server_name(SSL *s, unsigned int context, int sent)
896 int ret = SSL_TLSEXT_ERR_NOACK, discard;
897 int altmp = SSL_AD_UNRECOGNIZED_NAME;
898 int was_ticket = (SSL_get_options(s) & SSL_OP_NO_TICKET) == 0;
900 if (s->ctx != NULL && s->ctx->ext.servername_cb != 0)
901 ret = s->ctx->ext.servername_cb(s, &altmp,
902 s->ctx->ext.servername_arg);
903 else if (s->session_ctx != NULL
904 && s->session_ctx->ext.servername_cb != 0)
905 ret = s->session_ctx->ext.servername_cb(s, &altmp,
906 s->session_ctx->ext.servername_arg);
909 OPENSSL_free(s->session->ext.hostname);
910 s->session->ext.hostname = NULL;
914 * If we switched contexts (whether here or in the client_hello callback),
915 * move the sess_accept increment from the session_ctx to the new
916 * context, to avoid the confusing situation of having sess_accept_good
917 * exceed sess_accept (zero) for the new context.
919 if (SSL_IS_FIRST_HANDSHAKE(s) && s->ctx != s->session_ctx) {
920 CRYPTO_atomic_add(&s->ctx->stats.sess_accept, 1, &discard,
922 CRYPTO_atomic_add(&s->session_ctx->stats.sess_accept, -1, &discard,
923 s->session_ctx->lock);
927 * If we're expecting to send a ticket, and tickets were previously enabled,
928 * and now tickets are disabled, then turn off expected ticket.
929 * Also, if this is not a resumption, create a new session ID
931 if (ret == SSL_TLSEXT_ERR_OK && s->ext.ticket_expected
932 && was_ticket && (SSL_get_options(s) & SSL_OP_NO_TICKET) != 0) {
933 s->ext.ticket_expected = 0;
935 SSL_SESSION* ss = SSL_get_session(s);
938 OPENSSL_free(ss->ext.tick);
941 ss->ext.tick_lifetime_hint = 0;
942 ss->ext.tick_age_add = 0;
943 ss->ext.tick_identity = 0;
944 if (!ssl_generate_session_id(s, ss)) {
945 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_SERVER_NAME,
946 ERR_R_INTERNAL_ERROR);
950 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_SERVER_NAME,
951 ERR_R_INTERNAL_ERROR);
958 case SSL_TLSEXT_ERR_ALERT_FATAL:
959 SSLfatal(s, altmp, SSL_F_FINAL_SERVER_NAME, SSL_R_CALLBACK_FAILED);
962 case SSL_TLSEXT_ERR_ALERT_WARNING:
963 ssl3_send_alert(s, SSL3_AL_WARNING, altmp);
966 case SSL_TLSEXT_ERR_NOACK:
967 s->servername_done = 0;
975 #ifndef OPENSSL_NO_EC
976 static int final_ec_pt_formats(SSL *s, unsigned int context, int sent)
978 unsigned long alg_k, alg_a;
983 alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
984 alg_a = s->s3->tmp.new_cipher->algorithm_auth;
987 * If we are client and using an elliptic curve cryptography cipher
988 * suite, then if server returns an EC point formats lists extension it
989 * must contain uncompressed.
991 if (s->ext.ecpointformats != NULL
992 && s->ext.ecpointformats_len > 0
993 && s->session->ext.ecpointformats != NULL
994 && s->session->ext.ecpointformats_len > 0
995 && ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA))) {
996 /* we are using an ECC cipher */
998 unsigned char *list = s->session->ext.ecpointformats;
1000 for (i = 0; i < s->session->ext.ecpointformats_len; i++) {
1001 if (*list++ == TLSEXT_ECPOINTFORMAT_uncompressed)
1004 if (i == s->session->ext.ecpointformats_len) {
1005 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_FINAL_EC_PT_FORMATS,
1006 SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
1015 static int init_session_ticket(SSL *s, unsigned int context)
1018 s->ext.ticket_expected = 0;
1023 #ifndef OPENSSL_NO_OCSP
1024 static int init_status_request(SSL *s, unsigned int context)
1027 s->ext.status_type = TLSEXT_STATUSTYPE_nothing;
1030 * Ensure we get sensible values passed to tlsext_status_cb in the event
1031 * that we don't receive a status message
1033 OPENSSL_free(s->ext.ocsp.resp);
1034 s->ext.ocsp.resp = NULL;
1035 s->ext.ocsp.resp_len = 0;
1042 #ifndef OPENSSL_NO_NEXTPROTONEG
1043 static int init_npn(SSL *s, unsigned int context)
1045 s->s3->npn_seen = 0;
1051 static int init_alpn(SSL *s, unsigned int context)
1053 OPENSSL_free(s->s3->alpn_selected);
1054 s->s3->alpn_selected = NULL;
1055 s->s3->alpn_selected_len = 0;
1057 OPENSSL_free(s->s3->alpn_proposed);
1058 s->s3->alpn_proposed = NULL;
1059 s->s3->alpn_proposed_len = 0;
1064 static int final_alpn(SSL *s, unsigned int context, int sent)
1066 if (!s->server && !sent && s->session->ext.alpn_selected != NULL)
1067 s->ext.early_data_ok = 0;
1069 if (!s->server || !SSL_IS_TLS13(s))
1073 * Call alpn_select callback if needed. Has to be done after SNI and
1074 * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
1075 * we also have to do this before we decide whether to accept early_data.
1076 * In TLSv1.3 we've already negotiated our cipher so we do this call now.
1077 * For < TLSv1.3 we defer it until after cipher negotiation.
1079 * On failure SSLfatal() already called.
1081 return tls_handle_alpn(s);
1084 static int init_sig_algs(SSL *s, unsigned int context)
1086 /* Clear any signature algorithms extension received */
1087 OPENSSL_free(s->s3->tmp.peer_sigalgs);
1088 s->s3->tmp.peer_sigalgs = NULL;
1093 #ifndef OPENSSL_NO_SRP
1094 static int init_srp(SSL *s, unsigned int context)
1096 OPENSSL_free(s->srp_ctx.login);
1097 s->srp_ctx.login = NULL;
1103 static int init_etm(SSL *s, unsigned int context)
1110 static int init_ems(SSL *s, unsigned int context)
1113 s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS;
1118 static int final_ems(SSL *s, unsigned int context, int sent)
1120 if (!s->server && s->hit) {
1122 * Check extended master secret extension is consistent with
1125 if (!(s->s3->flags & TLS1_FLAGS_RECEIVED_EXTMS) !=
1126 !(s->session->flags & SSL_SESS_FLAG_EXTMS)) {
1127 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_FINAL_EMS,
1128 SSL_R_INCONSISTENT_EXTMS);
1136 static int init_certificate_authorities(SSL *s, unsigned int context)
1138 sk_X509_NAME_pop_free(s->s3->tmp.peer_ca_names, X509_NAME_free);
1139 s->s3->tmp.peer_ca_names = NULL;
1143 static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
1144 unsigned int context,
1148 const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s);
1150 if (ca_sk == NULL || sk_X509_NAME_num(ca_sk) == 0)
1151 return EXT_RETURN_NOT_SENT;
1153 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_certificate_authorities)
1154 || !WPACKET_start_sub_packet_u16(pkt)) {
1155 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1156 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES,
1157 ERR_R_INTERNAL_ERROR);
1158 return EXT_RETURN_FAIL;
1161 if (!construct_ca_names(s, pkt)) {
1162 /* SSLfatal() already called */
1163 return EXT_RETURN_FAIL;
1166 if (!WPACKET_close(pkt)) {
1167 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1168 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES,
1169 ERR_R_INTERNAL_ERROR);
1170 return EXT_RETURN_FAIL;
1173 return EXT_RETURN_SENT;
1176 static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt,
1177 unsigned int context, X509 *x,
1180 if (!parse_ca_names(s, pkt))
1182 if (PACKET_remaining(pkt) != 0) {
1183 SSLfatal(s, SSL_AD_DECODE_ERROR,
1184 SSL_F_TLS_PARSE_CERTIFICATE_AUTHORITIES, SSL_R_BAD_EXTENSION);
1190 #ifndef OPENSSL_NO_SRTP
1191 static int init_srtp(SSL *s, unsigned int context)
1194 s->srtp_profile = NULL;
1200 static int final_sig_algs(SSL *s, unsigned int context, int sent)
1202 if (!sent && SSL_IS_TLS13(s) && !s->hit) {
1203 SSLfatal(s, TLS13_AD_MISSING_EXTENSION, SSL_F_FINAL_SIG_ALGS,
1204 SSL_R_MISSING_SIGALGS_EXTENSION);
1211 #ifndef OPENSSL_NO_EC
1212 static int final_key_share(SSL *s, unsigned int context, int sent)
1214 if (!SSL_IS_TLS13(s))
1217 /* Nothing to do for key_share in an HRR */
1218 if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0)
1225 * we have no key_share
1227 * (we are not resuming
1228 * OR the kex_mode doesn't allow non key_share resumes)
1235 || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0)) {
1236 /* Nothing left we can do - just fail */
1237 SSLfatal(s, SSL_AD_MISSING_EXTENSION, SSL_F_FINAL_KEY_SHARE,
1238 SSL_R_NO_SUITABLE_KEY_SHARE);
1246 * we have a suitable key_share
1249 * we are stateless AND we have no cookie
1251 * send a HelloRetryRequest
1254 * we didn't already send a HelloRetryRequest
1256 * the client sent a key_share extension
1258 * (we are not resuming
1259 * OR the kex_mode allows key_share resumes)
1261 * a shared group exists
1263 * send a HelloRetryRequest
1265 * we are not resuming
1267 * the kex_mode doesn't allow non key_share resumes
1271 * we are stateless AND we have no cookie
1273 * send a HelloRetryRequest
1276 if (s->s3->peer_tmp != NULL) {
1277 /* We have a suitable key_share */
1278 if ((s->s3->flags & TLS1_FLAGS_STATELESS) != 0
1279 && !s->ext.cookieok) {
1280 if (!ossl_assert(s->hello_retry_request == SSL_HRR_NONE)) {
1282 * If we are stateless then we wouldn't know about any
1283 * previously sent HRR - so how can this be anything other
1286 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_KEY_SHARE,
1287 ERR_R_INTERNAL_ERROR);
1290 s->hello_retry_request = SSL_HRR_PENDING;
1294 /* No suitable key_share */
1295 if (s->hello_retry_request == SSL_HRR_NONE && sent
1297 || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE)
1299 const uint16_t *pgroups, *clntgroups;
1300 size_t num_groups, clnt_num_groups, i;
1301 unsigned int group_id = 0;
1303 /* Check if a shared group exists */
1305 /* Get the clients list of supported groups. */
1306 tls1_get_peer_groups(s, &clntgroups, &clnt_num_groups);
1307 tls1_get_supported_groups(s, &pgroups, &num_groups);
1310 * Find the first group we allow that is also in client's list
1312 for (i = 0; i < num_groups; i++) {
1313 group_id = pgroups[i];
1315 if (check_in_list(s, group_id, clntgroups, clnt_num_groups,
1320 if (i < num_groups) {
1321 /* A shared group exists so send a HelloRetryRequest */
1322 s->s3->group_id = group_id;
1323 s->hello_retry_request = SSL_HRR_PENDING;
1328 || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0) {
1329 /* Nothing left we can do - just fail */
1330 SSLfatal(s, sent ? SSL_AD_HANDSHAKE_FAILURE
1331 : SSL_AD_MISSING_EXTENSION,
1332 SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE);
1336 if ((s->s3->flags & TLS1_FLAGS_STATELESS) != 0
1337 && !s->ext.cookieok) {
1338 if (!ossl_assert(s->hello_retry_request == SSL_HRR_NONE)) {
1340 * If we are stateless then we wouldn't know about any
1341 * previously sent HRR - so how can this be anything other
1344 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_KEY_SHARE,
1345 ERR_R_INTERNAL_ERROR);
1348 s->hello_retry_request = SSL_HRR_PENDING;
1354 * We have a key_share so don't send any more HelloRetryRequest
1357 if (s->hello_retry_request == SSL_HRR_PENDING)
1358 s->hello_retry_request = SSL_HRR_COMPLETE;
1361 * For a client side resumption with no key_share we need to generate
1362 * the handshake secret (otherwise this is done during key_share
1365 if (!sent && !tls13_generate_handshake_secret(s, NULL, 0)) {
1366 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_FINAL_KEY_SHARE,
1367 ERR_R_INTERNAL_ERROR);
1376 static int init_psk_kex_modes(SSL *s, unsigned int context)
1378 s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_NONE;
1382 int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart,
1383 size_t binderoffset, const unsigned char *binderin,
1384 unsigned char *binderout, SSL_SESSION *sess, int sign,
1387 EVP_PKEY *mackey = NULL;
1388 EVP_MD_CTX *mctx = NULL;
1389 unsigned char hash[EVP_MAX_MD_SIZE], binderkey[EVP_MAX_MD_SIZE];
1390 unsigned char finishedkey[EVP_MAX_MD_SIZE], tmpbinder[EVP_MAX_MD_SIZE];
1391 unsigned char tmppsk[EVP_MAX_MD_SIZE];
1392 unsigned char *early_secret, *psk;
1393 const char resumption_label[] = "res binder";
1394 const char external_label[] = "ext binder";
1395 const char nonce_label[] = "resumption";
1397 size_t bindersize, labelsize, hashsize = EVP_MD_size(md);
1399 int usepskfored = 0;
1402 && s->early_data_state == SSL_EARLY_DATA_CONNECTING
1403 && s->session->ext.max_early_data == 0
1404 && sess->ext.max_early_data > 0)
1408 label = external_label;
1409 labelsize = sizeof(external_label) - 1;
1411 label = resumption_label;
1412 labelsize = sizeof(resumption_label) - 1;
1415 if (sess->master_key_length != hashsize) {
1416 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1422 psk = sess->master_key;
1425 if (!tls13_hkdf_expand(s, md, sess->master_key,
1426 (const unsigned char *)nonce_label,
1427 sizeof(nonce_label) - 1, sess->ext.tick_nonce,
1428 sess->ext.tick_nonce_len, psk, hashsize)) {
1429 /* SSLfatal() already called */
1435 * Generate the early_secret. On the server side we've selected a PSK to
1436 * resume with (internal or external) so we always do this. On the client
1437 * side we do this for a non-external (i.e. resumption) PSK or external PSK
1438 * that will be used for early_data so that it is in place for sending early
1439 * data. For client side external PSK not being used for early_data we
1440 * generate it but store it away for later use.
1442 if (s->server || !external || usepskfored)
1443 early_secret = (unsigned char *)s->early_secret;
1445 early_secret = (unsigned char *)sess->early_secret;
1446 if (!tls13_generate_secret(s, md, NULL, psk, hashsize, early_secret)) {
1447 /* SSLfatal() already called */
1452 * Create the handshake hash for the binder key...the messages so far are
1455 mctx = EVP_MD_CTX_new();
1457 || EVP_DigestInit_ex(mctx, md, NULL) <= 0
1458 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
1459 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1460 ERR_R_INTERNAL_ERROR);
1464 /* Generate the binder key */
1465 if (!tls13_hkdf_expand(s, md, early_secret, (unsigned char *)label,
1466 labelsize, hash, hashsize, binderkey, hashsize)) {
1467 /* SSLfatal() already called */
1471 /* Generate the finished key */
1472 if (!tls13_derive_finishedkey(s, md, binderkey, finishedkey, hashsize)) {
1473 /* SSLfatal() already called */
1477 if (EVP_DigestInit_ex(mctx, md, NULL) <= 0) {
1478 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1479 ERR_R_INTERNAL_ERROR);
1484 * Get a hash of the ClientHello up to the start of the binders. If we are
1485 * following a HelloRetryRequest then this includes the hash of the first
1486 * ClientHello and the HelloRetryRequest itself.
1488 if (s->hello_retry_request == SSL_HRR_PENDING) {
1492 hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
1493 if (hdatalen <= 0) {
1494 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1495 SSL_R_BAD_HANDSHAKE_LENGTH);
1500 * For servers the handshake buffer data will include the second
1501 * ClientHello - which we don't want - so we need to take that bit off.
1504 PACKET hashprefix, msg;
1506 /* Find how many bytes are left after the first two messages */
1507 if (!PACKET_buf_init(&hashprefix, hdata, hdatalen)
1508 || !PACKET_forward(&hashprefix, 1)
1509 || !PACKET_get_length_prefixed_3(&hashprefix, &msg)
1510 || !PACKET_forward(&hashprefix, 1)
1511 || !PACKET_get_length_prefixed_3(&hashprefix, &msg)) {
1512 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1513 ERR_R_INTERNAL_ERROR);
1516 hdatalen -= PACKET_remaining(&hashprefix);
1519 if (EVP_DigestUpdate(mctx, hdata, hdatalen) <= 0) {
1520 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1521 ERR_R_INTERNAL_ERROR);
1526 if (EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0
1527 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
1528 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1529 ERR_R_INTERNAL_ERROR);
1533 mackey = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, finishedkey, hashsize);
1534 if (mackey == NULL) {
1535 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1536 ERR_R_INTERNAL_ERROR);
1541 binderout = tmpbinder;
1543 bindersize = hashsize;
1544 if (EVP_DigestSignInit(mctx, NULL, md, NULL, mackey) <= 0
1545 || EVP_DigestSignUpdate(mctx, hash, hashsize) <= 0
1546 || EVP_DigestSignFinal(mctx, binderout, &bindersize) <= 0
1547 || bindersize != hashsize) {
1548 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PSK_DO_BINDER,
1549 ERR_R_INTERNAL_ERROR);
1556 /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */
1557 ret = (CRYPTO_memcmp(binderin, binderout, hashsize) == 0);
1559 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_TLS_PSK_DO_BINDER,
1560 SSL_R_BINDER_DOES_NOT_VERIFY);
1564 OPENSSL_cleanse(binderkey, sizeof(binderkey));
1565 OPENSSL_cleanse(finishedkey, sizeof(finishedkey));
1566 EVP_PKEY_free(mackey);
1567 EVP_MD_CTX_free(mctx);
1572 static int final_early_data(SSL *s, unsigned int context, int sent)
1578 if (context == SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
1580 && !s->ext.early_data_ok) {
1582 * If we get here then the server accepted our early_data but we
1583 * later realised that it shouldn't have done (e.g. inconsistent
1586 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_FINAL_EARLY_DATA,
1587 SSL_R_BAD_EARLY_DATA);
1594 if (s->max_early_data == 0
1596 || s->session->ext.tick_identity != 0
1597 || s->early_data_state != SSL_EARLY_DATA_ACCEPTING
1598 || !s->ext.early_data_ok
1599 || s->hello_retry_request != SSL_HRR_NONE) {
1600 s->ext.early_data = SSL_EARLY_DATA_REJECTED;
1602 s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
1604 if (!tls13_change_cipher_state(s,
1605 SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_SERVER_READ)) {
1606 /* SSLfatal() already called */
1614 static int final_maxfragmentlen(SSL *s, unsigned int context, int sent)
1617 * Session resumption on server-side with MFL extension active
1618 * BUT MFL extension packet was not resent (i.e. sent == 0)
1620 if (s->server && s->hit && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
1622 SSLfatal(s, SSL_AD_MISSING_EXTENSION, SSL_F_FINAL_MAXFRAGMENTLEN,
1623 SSL_R_BAD_EXTENSION);
1627 /* Current SSL buffer is lower than requested MFL */
1628 if (s->session && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
1629 && s->max_send_fragment < GET_MAX_FRAGMENT_LENGTH(s->session))
1630 /* trigger a larger buffer reallocation */
1631 if (!ssl3_setup_buffers(s)) {
1632 /* SSLfatal() already called */