2 * Copyright 2016-2020 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (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_local.h"
14 #include "statem_local.h"
15 #include "internal/cryptlib.h"
17 DEFINE_STACK_OF(X509_NAME
)
19 static int final_renegotiate(SSL
*s
, unsigned int context
, int sent
);
20 static int init_server_name(SSL
*s
, unsigned int context
);
21 static int final_server_name(SSL
*s
, unsigned int context
, int sent
);
23 static int final_ec_pt_formats(SSL
*s
, unsigned int context
, int sent
);
25 static int init_session_ticket(SSL
*s
, unsigned int context
);
26 #ifndef OPENSSL_NO_OCSP
27 static int init_status_request(SSL
*s
, unsigned int context
);
29 #ifndef OPENSSL_NO_NEXTPROTONEG
30 static int init_npn(SSL
*s
, unsigned int context
);
32 static int init_alpn(SSL
*s
, unsigned int context
);
33 static int final_alpn(SSL
*s
, unsigned int context
, int sent
);
34 static int init_sig_algs_cert(SSL
*s
, unsigned int context
);
35 static int init_sig_algs(SSL
*s
, unsigned int context
);
36 static int init_certificate_authorities(SSL
*s
, unsigned int context
);
37 static EXT_RETURN
tls_construct_certificate_authorities(SSL
*s
, WPACKET
*pkt
,
41 static int tls_parse_certificate_authorities(SSL
*s
, PACKET
*pkt
,
42 unsigned int context
, X509
*x
,
44 #ifndef OPENSSL_NO_SRP
45 static int init_srp(SSL
*s
, unsigned int context
);
47 static int init_etm(SSL
*s
, unsigned int context
);
48 static int init_ems(SSL
*s
, unsigned int context
);
49 static int final_ems(SSL
*s
, unsigned int context
, int sent
);
50 static int init_psk_kex_modes(SSL
*s
, unsigned int context
);
51 static int final_key_share(SSL
*s
, unsigned int context
, int sent
);
52 #ifndef OPENSSL_NO_SRTP
53 static int init_srtp(SSL
*s
, unsigned int context
);
55 static int final_sig_algs(SSL
*s
, unsigned int context
, int sent
);
56 static int final_early_data(SSL
*s
, unsigned int context
, int sent
);
57 static int final_maxfragmentlen(SSL
*s
, unsigned int context
, int sent
);
58 static int init_post_handshake_auth(SSL
*s
, unsigned int context
);
60 /* Structure to define a built-in extension */
61 typedef struct extensions_definition_st
{
62 /* The defined type for the extension */
65 * The context that this extension applies to, e.g. what messages and
70 * Initialise extension before parsing. Always called for relevant contexts
71 * even if extension not present
73 int (*init
)(SSL
*s
, unsigned int context
);
74 /* Parse extension sent from client to server */
75 int (*parse_ctos
)(SSL
*s
, PACKET
*pkt
, unsigned int context
, X509
*x
,
77 /* Parse extension send from server to client */
78 int (*parse_stoc
)(SSL
*s
, PACKET
*pkt
, unsigned int context
, X509
*x
,
80 /* Construct extension sent from server to client */
81 EXT_RETURN (*construct_stoc
)(SSL
*s
, WPACKET
*pkt
, unsigned int context
,
82 X509
*x
, size_t chainidx
);
83 /* Construct extension sent from client to server */
84 EXT_RETURN (*construct_ctos
)(SSL
*s
, WPACKET
*pkt
, unsigned int context
,
85 X509
*x
, size_t chainidx
);
87 * Finalise extension after parsing. Always called where an extensions was
88 * initialised even if the extension was not present. |sent| is set to 1 if
89 * the extension was seen, or 0 otherwise.
91 int (*final
)(SSL
*s
, unsigned int context
, int sent
);
92 } EXTENSION_DEFINITION
;
95 * Definitions of all built-in extensions. NOTE: Changes in the number or order
96 * of these extensions should be mirrored with equivalent changes to the
97 * indexes ( TLSEXT_IDX_* ) defined in ssl_local.h.
98 * Each extension has an initialiser, a client and
99 * server side parser and a finaliser. The initialiser is called (if the
100 * extension is relevant to the given context) even if we did not see the
101 * extension in the message that we received. The parser functions are only
102 * called if we see the extension in the message. The finalisers are always
103 * called if the initialiser was called.
104 * There are also server and client side constructor functions which are always
105 * called during message construction if the extension is relevant for the
107 * The initialisation, parsing, finalisation and construction functions are
108 * always called in the order defined in this list. Some extensions may depend
109 * on others having been processed first, so the order of this list is
111 * The extension context is defined by a series of flags which specify which
112 * messages the extension is relevant to. These flags also specify whether the
113 * extension is relevant to a particular protocol or protocol version.
115 * TODO(TLS1.3): Make sure we have a test to check the consistency of these
117 * NOTE: WebSphere Application Server 7+ cannot handle empty extensions at
118 * the end, keep these extensions before signature_algorithm.
120 #define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL }
121 static const EXTENSION_DEFINITION ext_defs
[] = {
123 TLSEXT_TYPE_renegotiate
,
124 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
125 | SSL_EXT_SSL3_ALLOWED
| SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
126 NULL
, tls_parse_ctos_renegotiate
, tls_parse_stoc_renegotiate
,
127 tls_construct_stoc_renegotiate
, tls_construct_ctos_renegotiate
,
131 TLSEXT_TYPE_server_name
,
132 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
133 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
135 tls_parse_ctos_server_name
, tls_parse_stoc_server_name
,
136 tls_construct_stoc_server_name
, tls_construct_ctos_server_name
,
140 TLSEXT_TYPE_max_fragment_length
,
141 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
142 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
143 NULL
, tls_parse_ctos_maxfragmentlen
, tls_parse_stoc_maxfragmentlen
,
144 tls_construct_stoc_maxfragmentlen
, tls_construct_ctos_maxfragmentlen
,
147 #ifndef OPENSSL_NO_SRP
150 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
151 init_srp
, tls_parse_ctos_srp
, NULL
, NULL
, tls_construct_ctos_srp
, NULL
156 #ifndef OPENSSL_NO_EC
158 TLSEXT_TYPE_ec_point_formats
,
159 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
160 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
161 NULL
, tls_parse_ctos_ec_pt_formats
, tls_parse_stoc_ec_pt_formats
,
162 tls_construct_stoc_ec_pt_formats
, tls_construct_ctos_ec_pt_formats
,
168 #if !defined(OPENSSL_NO_EC) || !defined(OPENSSL_NO_DH)
171 * "supported_groups" is spread across several specifications.
172 * It was originally specified as "elliptic_curves" in RFC 4492,
173 * and broadened to include named FFDH groups by RFC 7919.
174 * Both RFCs 4492 and 7919 do not include a provision for the server
175 * to indicate to the client the complete list of groups supported
176 * by the server, with the server instead just indicating the
177 * selected group for this connection in the ServerKeyExchange
178 * message. TLS 1.3 adds a scheme for the server to indicate
179 * to the client its list of supported groups in the
180 * EncryptedExtensions message, but none of the relevant
181 * specifications permit sending supported_groups in the ServerHello.
182 * Nonetheless (possibly due to the close proximity to the
183 * "ec_point_formats" extension, which is allowed in the ServerHello),
184 * there are several servers that send this extension in the
185 * ServerHello anyway. Up to and including the 1.1.0 release,
186 * we did not check for the presence of nonpermitted extensions,
187 * so to avoid a regression, we must permit this extension in the
188 * TLS 1.2 ServerHello as well.
190 * Note that there is no tls_parse_stoc_supported_groups function,
191 * so we do not perform any additional parsing, validation, or
192 * processing on the server's group list -- this is just a minimal
193 * change to preserve compatibility with these misbehaving servers.
195 TLSEXT_TYPE_supported_groups
,
196 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
197 | SSL_EXT_TLS1_2_SERVER_HELLO
,
198 NULL
, tls_parse_ctos_supported_groups
, NULL
,
199 tls_construct_stoc_supported_groups
,
200 tls_construct_ctos_supported_groups
, NULL
206 TLSEXT_TYPE_session_ticket
,
207 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
208 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
209 init_session_ticket
, tls_parse_ctos_session_ticket
,
210 tls_parse_stoc_session_ticket
, tls_construct_stoc_session_ticket
,
211 tls_construct_ctos_session_ticket
, NULL
213 #ifndef OPENSSL_NO_OCSP
215 TLSEXT_TYPE_status_request
,
216 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
217 | SSL_EXT_TLS1_3_CERTIFICATE
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
218 init_status_request
, tls_parse_ctos_status_request
,
219 tls_parse_stoc_status_request
, tls_construct_stoc_status_request
,
220 tls_construct_ctos_status_request
, NULL
225 #ifndef OPENSSL_NO_NEXTPROTONEG
227 TLSEXT_TYPE_next_proto_neg
,
228 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
229 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
230 init_npn
, tls_parse_ctos_npn
, tls_parse_stoc_npn
,
231 tls_construct_stoc_next_proto_neg
, tls_construct_ctos_npn
, NULL
238 * Must appear in this list after server_name so that finalisation
239 * happens after server_name callbacks
241 TLSEXT_TYPE_application_layer_protocol_negotiation
,
242 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
243 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
244 init_alpn
, tls_parse_ctos_alpn
, tls_parse_stoc_alpn
,
245 tls_construct_stoc_alpn
, tls_construct_ctos_alpn
, final_alpn
247 #ifndef OPENSSL_NO_SRTP
249 TLSEXT_TYPE_use_srtp
,
250 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
251 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
| SSL_EXT_DTLS_ONLY
,
252 init_srtp
, tls_parse_ctos_use_srtp
, tls_parse_stoc_use_srtp
,
253 tls_construct_stoc_use_srtp
, tls_construct_ctos_use_srtp
, NULL
259 TLSEXT_TYPE_encrypt_then_mac
,
260 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
261 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
262 init_etm
, tls_parse_ctos_etm
, tls_parse_stoc_etm
,
263 tls_construct_stoc_etm
, tls_construct_ctos_etm
, NULL
265 #ifndef OPENSSL_NO_CT
267 TLSEXT_TYPE_signed_certificate_timestamp
,
268 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
269 | SSL_EXT_TLS1_3_CERTIFICATE
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
272 * No server side support for this, but can be provided by a custom
273 * extension. This is an exception to the rule that custom extensions
274 * cannot override built in ones.
276 NULL
, tls_parse_stoc_sct
, NULL
, tls_construct_ctos_sct
, NULL
282 TLSEXT_TYPE_extended_master_secret
,
283 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
284 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
285 init_ems
, tls_parse_ctos_ems
, tls_parse_stoc_ems
,
286 tls_construct_stoc_ems
, tls_construct_ctos_ems
, final_ems
289 TLSEXT_TYPE_signature_algorithms_cert
,
290 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
291 init_sig_algs_cert
, tls_parse_ctos_sig_algs_cert
,
292 tls_parse_ctos_sig_algs_cert
,
293 /* We do not generate signature_algorithms_cert at present. */
297 TLSEXT_TYPE_post_handshake_auth
,
298 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ONLY
,
299 init_post_handshake_auth
,
300 tls_parse_ctos_post_handshake_auth
, NULL
,
301 NULL
, tls_construct_ctos_post_handshake_auth
,
305 TLSEXT_TYPE_signature_algorithms
,
306 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
307 init_sig_algs
, tls_parse_ctos_sig_algs
,
308 tls_parse_ctos_sig_algs
, tls_construct_ctos_sig_algs
,
309 tls_construct_ctos_sig_algs
, final_sig_algs
312 TLSEXT_TYPE_supported_versions
,
313 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
314 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
,
316 /* Processed inline as part of version selection */
317 NULL
, tls_parse_stoc_supported_versions
,
318 tls_construct_stoc_supported_versions
,
319 tls_construct_ctos_supported_versions
, NULL
322 TLSEXT_TYPE_psk_kex_modes
,
323 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
324 | SSL_EXT_TLS1_3_ONLY
,
325 init_psk_kex_modes
, tls_parse_ctos_psk_kex_modes
, NULL
, NULL
,
326 tls_construct_ctos_psk_kex_modes
, NULL
330 * Must be in this list after supported_groups. We need that to have
331 * been parsed before we do this one.
333 TLSEXT_TYPE_key_share
,
334 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
335 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
336 | SSL_EXT_TLS1_3_ONLY
,
337 NULL
, tls_parse_ctos_key_share
, tls_parse_stoc_key_share
,
338 tls_construct_stoc_key_share
, tls_construct_ctos_key_share
,
342 /* Must be after key_share */
344 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
345 | SSL_EXT_TLS_IMPLEMENTATION_ONLY
| SSL_EXT_TLS1_3_ONLY
,
346 NULL
, tls_parse_ctos_cookie
, tls_parse_stoc_cookie
,
347 tls_construct_stoc_cookie
, tls_construct_ctos_cookie
, NULL
351 * Special unsolicited ServerHello extension only used when
352 * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set. We allow it in a ClientHello but
355 TLSEXT_TYPE_cryptopro_bug
,
356 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
357 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
358 NULL
, NULL
, NULL
, tls_construct_stoc_cryptopro_bug
, NULL
, NULL
361 TLSEXT_TYPE_early_data
,
362 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
363 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
| SSL_EXT_TLS1_3_ONLY
,
364 NULL
, tls_parse_ctos_early_data
, tls_parse_stoc_early_data
,
365 tls_construct_stoc_early_data
, tls_construct_ctos_early_data
,
369 TLSEXT_TYPE_certificate_authorities
,
370 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
371 | SSL_EXT_TLS1_3_ONLY
,
372 init_certificate_authorities
,
373 tls_parse_certificate_authorities
, tls_parse_certificate_authorities
,
374 tls_construct_certificate_authorities
,
375 tls_construct_certificate_authorities
, NULL
,
378 /* Must be immediately before pre_shared_key */
380 SSL_EXT_CLIENT_HELLO
,
382 /* We send this, but don't read it */
383 NULL
, NULL
, NULL
, tls_construct_ctos_padding
, NULL
386 /* Required by the TLSv1.3 spec to always be the last extension */
388 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
389 | SSL_EXT_TLS_IMPLEMENTATION_ONLY
| SSL_EXT_TLS1_3_ONLY
,
390 NULL
, tls_parse_ctos_psk
, tls_parse_stoc_psk
, tls_construct_stoc_psk
,
391 tls_construct_ctos_psk
, NULL
395 /* Check whether an extension's context matches the current context */
396 static int validate_context(SSL
*s
, unsigned int extctx
, unsigned int thisctx
)
398 /* Check we're allowed to use this extension in this context */
399 if ((thisctx
& extctx
) == 0)
402 if (SSL_IS_DTLS(s
)) {
403 if ((extctx
& SSL_EXT_TLS_ONLY
) != 0)
405 } else if ((extctx
& SSL_EXT_DTLS_ONLY
) != 0) {
412 int tls_validate_all_contexts(SSL
*s
, unsigned int thisctx
, RAW_EXTENSION
*exts
)
414 size_t i
, num_exts
, builtin_num
= OSSL_NELEM(ext_defs
), offset
;
415 RAW_EXTENSION
*thisext
;
416 unsigned int context
;
417 ENDPOINT role
= ENDPOINT_BOTH
;
419 if ((thisctx
& SSL_EXT_CLIENT_HELLO
) != 0)
420 role
= ENDPOINT_SERVER
;
421 else if ((thisctx
& SSL_EXT_TLS1_2_SERVER_HELLO
) != 0)
422 role
= ENDPOINT_CLIENT
;
424 /* Calculate the number of extensions in the extensions list */
425 num_exts
= builtin_num
+ s
->cert
->custext
.meths_count
;
427 for (thisext
= exts
, i
= 0; i
< num_exts
; i
++, thisext
++) {
428 if (!thisext
->present
)
431 if (i
< builtin_num
) {
432 context
= ext_defs
[i
].context
;
434 custom_ext_method
*meth
= NULL
;
436 meth
= custom_ext_find(&s
->cert
->custext
, role
, thisext
->type
,
438 if (!ossl_assert(meth
!= NULL
))
440 context
= meth
->context
;
443 if (!validate_context(s
, context
, thisctx
))
451 * Verify whether we are allowed to use the extension |type| in the current
452 * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to
453 * indicate the extension is not allowed. If returning 1 then |*found| is set to
454 * the definition for the extension we found.
456 static int verify_extension(SSL
*s
, unsigned int context
, unsigned int type
,
457 custom_ext_methods
*meths
, RAW_EXTENSION
*rawexlist
,
458 RAW_EXTENSION
**found
)
461 size_t builtin_num
= OSSL_NELEM(ext_defs
);
462 const EXTENSION_DEFINITION
*thisext
;
464 for (i
= 0, thisext
= ext_defs
; i
< builtin_num
; i
++, thisext
++) {
465 if (type
== thisext
->type
) {
466 if (!validate_context(s
, thisext
->context
, context
))
469 *found
= &rawexlist
[i
];
474 /* Check the custom extensions */
477 ENDPOINT role
= ENDPOINT_BOTH
;
478 custom_ext_method
*meth
= NULL
;
480 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0)
481 role
= ENDPOINT_SERVER
;
482 else if ((context
& SSL_EXT_TLS1_2_SERVER_HELLO
) != 0)
483 role
= ENDPOINT_CLIENT
;
485 meth
= custom_ext_find(meths
, role
, type
, &offset
);
487 if (!validate_context(s
, meth
->context
, context
))
489 *found
= &rawexlist
[offset
+ builtin_num
];
494 /* Unknown extension. We allow it */
500 * Check whether the context defined for an extension |extctx| means whether
501 * the extension is relevant for the current context |thisctx| or not. Returns
502 * 1 if the extension is relevant for this context, and 0 otherwise
504 int extension_is_relevant(SSL
*s
, unsigned int extctx
, unsigned int thisctx
)
509 * For HRR we haven't selected the version yet but we know it will be
512 if ((thisctx
& SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
) != 0)
515 is_tls13
= SSL_IS_TLS13(s
);
518 && (extctx
& SSL_EXT_TLS_IMPLEMENTATION_ONLY
) != 0)
519 || (s
->version
== SSL3_VERSION
520 && (extctx
& SSL_EXT_SSL3_ALLOWED
) == 0)
522 * Note that SSL_IS_TLS13() means "TLS 1.3 has been negotiated",
523 * which is never true when generating the ClientHello.
524 * However, version negotiation *has* occurred by the time the
525 * ClientHello extensions are being parsed.
526 * Be careful to allow TLS 1.3-only extensions when generating
529 || (is_tls13
&& (extctx
& SSL_EXT_TLS1_2_AND_BELOW_ONLY
) != 0)
530 || (!is_tls13
&& (extctx
& SSL_EXT_TLS1_3_ONLY
) != 0
531 && (thisctx
& SSL_EXT_CLIENT_HELLO
) == 0)
532 || (s
->server
&& !is_tls13
&& (extctx
& SSL_EXT_TLS1_3_ONLY
) != 0)
533 || (s
->hit
&& (extctx
& SSL_EXT_IGNORE_ON_RESUMPTION
) != 0))
539 * Gather a list of all the extensions from the data in |packet]. |context|
540 * tells us which message this extension is for. The raw extension data is
541 * stored in |*res| on success. We don't actually process the content of the
542 * extensions yet, except to check their types. This function also runs the
543 * initialiser functions for all known extensions if |init| is nonzero (whether
544 * we have collected them or not). If successful the caller is responsible for
545 * freeing the contents of |*res|.
547 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
548 * more than one extension of the same type in a ClientHello or ServerHello.
549 * This function returns 1 if all extensions are unique and we have parsed their
550 * types, and 0 if the extensions contain duplicates, could not be successfully
551 * found, or an internal error occurred. We only check duplicates for
552 * extensions that we know about. We ignore others.
554 int tls_collect_extensions(SSL
*s
, PACKET
*packet
, unsigned int context
,
555 RAW_EXTENSION
**res
, size_t *len
, int init
)
557 PACKET extensions
= *packet
;
560 custom_ext_methods
*exts
= &s
->cert
->custext
;
561 RAW_EXTENSION
*raw_extensions
= NULL
;
562 const EXTENSION_DEFINITION
*thisexd
;
567 * Initialise server side custom extensions. Client side is done during
568 * construction of extensions for the ClientHello.
570 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0)
571 custom_ext_init(&s
->cert
->custext
);
573 num_exts
= OSSL_NELEM(ext_defs
) + (exts
!= NULL
? exts
->meths_count
: 0);
574 raw_extensions
= OPENSSL_zalloc(num_exts
* sizeof(*raw_extensions
));
575 if (raw_extensions
== NULL
) {
576 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_COLLECT_EXTENSIONS
,
577 ERR_R_MALLOC_FAILURE
);
582 while (PACKET_remaining(&extensions
) > 0) {
583 unsigned int type
, idx
;
585 RAW_EXTENSION
*thisex
;
587 if (!PACKET_get_net_2(&extensions
, &type
) ||
588 !PACKET_get_length_prefixed_2(&extensions
, &extension
)) {
589 SSLfatal(s
, SSL_AD_DECODE_ERROR
, SSL_F_TLS_COLLECT_EXTENSIONS
,
590 SSL_R_BAD_EXTENSION
);
594 * Verify this extension is allowed. We only check duplicates for
595 * extensions that we recognise. We also have a special case for the
596 * PSK extension, which must be the last one in the ClientHello.
598 if (!verify_extension(s
, context
, type
, exts
, raw_extensions
, &thisex
)
599 || (thisex
!= NULL
&& thisex
->present
== 1)
600 || (type
== TLSEXT_TYPE_psk
601 && (context
& SSL_EXT_CLIENT_HELLO
) != 0
602 && PACKET_remaining(&extensions
) != 0)) {
603 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_TLS_COLLECT_EXTENSIONS
,
604 SSL_R_BAD_EXTENSION
);
607 idx
= thisex
- raw_extensions
;
609 * Check that we requested this extension (if appropriate). Requests can
610 * be sent in the ClientHello and CertificateRequest. Unsolicited
611 * extensions can be sent in the NewSessionTicket. We only do this for
612 * the built-in extensions. Custom extensions have a different but
613 * similar check elsewhere.
615 * - The HRR cookie extension is unsolicited
616 * - The renegotiate extension is unsolicited (the client signals
617 * support via an SCSV)
618 * - The signed_certificate_timestamp extension can be provided by a
619 * custom extension or by the built-in version. We let the extension
620 * itself handle unsolicited response checks.
622 if (idx
< OSSL_NELEM(ext_defs
)
623 && (context
& (SSL_EXT_CLIENT_HELLO
624 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
625 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
)) == 0
626 && type
!= TLSEXT_TYPE_cookie
627 && type
!= TLSEXT_TYPE_renegotiate
628 && type
!= TLSEXT_TYPE_signed_certificate_timestamp
629 && (s
->ext
.extflags
[idx
] & SSL_EXT_FLAG_SENT
) == 0
630 #ifndef OPENSSL_NO_GOST
631 && !((context
& SSL_EXT_TLS1_2_SERVER_HELLO
) != 0
632 && type
== TLSEXT_TYPE_cryptopro_bug
)
635 SSLfatal(s
, SSL_AD_UNSUPPORTED_EXTENSION
,
636 SSL_F_TLS_COLLECT_EXTENSIONS
, SSL_R_UNSOLICITED_EXTENSION
);
639 if (thisex
!= NULL
) {
640 thisex
->data
= extension
;
643 thisex
->received_order
= i
++;
645 s
->ext
.debug_cb(s
, !s
->server
, thisex
->type
,
646 PACKET_data(&thisex
->data
),
647 PACKET_remaining(&thisex
->data
),
654 * Initialise all known extensions relevant to this context,
655 * whether we have found them or not
657 for (thisexd
= ext_defs
, i
= 0; i
< OSSL_NELEM(ext_defs
);
659 if (thisexd
->init
!= NULL
&& (thisexd
->context
& context
) != 0
660 && extension_is_relevant(s
, thisexd
->context
, context
)
661 && !thisexd
->init(s
, context
)) {
662 /* SSLfatal() already called */
668 *res
= raw_extensions
;
674 OPENSSL_free(raw_extensions
);
679 * Runs the parser for a given extension with index |idx|. |exts| contains the
680 * list of all parsed extensions previously collected by
681 * tls_collect_extensions(). The parser is only run if it is applicable for the
682 * given |context| and the parser has not already been run. If this is for a
683 * Certificate message, then we also provide the parser with the relevant
684 * Certificate |x| and its position in the |chainidx| with 0 being the first
685 * Certificate. Returns 1 on success or 0 on failure. If an extension is not
686 * present this counted as success.
688 int tls_parse_extension(SSL
*s
, TLSEXT_INDEX idx
, int context
,
689 RAW_EXTENSION
*exts
, X509
*x
, size_t chainidx
)
691 RAW_EXTENSION
*currext
= &exts
[idx
];
692 int (*parser
)(SSL
*s
, PACKET
*pkt
, unsigned int context
, X509
*x
,
693 size_t chainidx
) = NULL
;
695 /* Skip if the extension is not present */
696 if (!currext
->present
)
699 /* Skip if we've already parsed this extension */
705 if (idx
< OSSL_NELEM(ext_defs
)) {
706 /* We are handling a built-in extension */
707 const EXTENSION_DEFINITION
*extdef
= &ext_defs
[idx
];
709 /* Check if extension is defined for our protocol. If not, skip */
710 if (!extension_is_relevant(s
, extdef
->context
, context
))
713 parser
= s
->server
? extdef
->parse_ctos
: extdef
->parse_stoc
;
716 return parser(s
, &currext
->data
, context
, x
, chainidx
);
719 * If the parser is NULL we fall through to the custom extension
724 /* Parse custom extensions */
725 return custom_ext_parse(s
, context
, currext
->type
,
726 PACKET_data(&currext
->data
),
727 PACKET_remaining(&currext
->data
),
732 * Parse all remaining extensions that have not yet been parsed. Also calls the
733 * finalisation for all extensions at the end if |fin| is nonzero, whether we
734 * collected them or not. Returns 1 for success or 0 for failure. If we are
735 * working on a Certificate message then we also pass the Certificate |x| and
736 * its position in the |chainidx|, with 0 being the first certificate.
738 int tls_parse_all_extensions(SSL
*s
, int context
, RAW_EXTENSION
*exts
, X509
*x
,
739 size_t chainidx
, int fin
)
741 size_t i
, numexts
= OSSL_NELEM(ext_defs
);
742 const EXTENSION_DEFINITION
*thisexd
;
744 /* Calculate the number of extensions in the extensions list */
745 numexts
+= s
->cert
->custext
.meths_count
;
747 /* Parse each extension in turn */
748 for (i
= 0; i
< numexts
; i
++) {
749 if (!tls_parse_extension(s
, i
, context
, exts
, x
, chainidx
)) {
750 /* SSLfatal() already called */
757 * Finalise all known extensions relevant to this context,
758 * whether we have found them or not
760 for (i
= 0, thisexd
= ext_defs
; i
< OSSL_NELEM(ext_defs
);
762 if (thisexd
->final
!= NULL
&& (thisexd
->context
& context
) != 0
763 && !thisexd
->final(s
, context
, exts
[i
].present
)) {
764 /* SSLfatal() already called */
773 int should_add_extension(SSL
*s
, unsigned int extctx
, unsigned int thisctx
,
776 /* Skip if not relevant for our context */
777 if ((extctx
& thisctx
) == 0)
780 /* Check if this extension is defined for our protocol. If not, skip */
781 if (!extension_is_relevant(s
, extctx
, thisctx
)
782 || ((extctx
& SSL_EXT_TLS1_3_ONLY
) != 0
783 && (thisctx
& SSL_EXT_CLIENT_HELLO
) != 0
784 && (SSL_IS_DTLS(s
) || max_version
< TLS1_3_VERSION
)))
791 * Construct all the extensions relevant to the current |context| and write
792 * them to |pkt|. If this is an extension for a Certificate in a Certificate
793 * message, then |x| will be set to the Certificate we are handling, and
794 * |chainidx| will indicate the position in the chainidx we are processing (with
795 * 0 being the first in the chain). Returns 1 on success or 0 on failure. On a
796 * failure construction stops at the first extension to fail to construct.
798 int tls_construct_extensions(SSL
*s
, WPACKET
*pkt
, unsigned int context
,
799 X509
*x
, size_t chainidx
)
802 int min_version
, max_version
= 0, reason
;
803 const EXTENSION_DEFINITION
*thisexd
;
805 if (!WPACKET_start_sub_packet_u16(pkt
)
807 * If extensions are of zero length then we don't even add the
808 * extensions length bytes to a ClientHello/ServerHello
812 (SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
)) != 0
813 && !WPACKET_set_flags(pkt
,
814 WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH
))) {
815 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_CONSTRUCT_EXTENSIONS
,
816 ERR_R_INTERNAL_ERROR
);
820 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0) {
821 reason
= ssl_get_min_max_version(s
, &min_version
, &max_version
, NULL
);
823 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_CONSTRUCT_EXTENSIONS
,
829 /* Add custom extensions first */
830 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0) {
831 /* On the server side with initialise during ClientHello parsing */
832 custom_ext_init(&s
->cert
->custext
);
834 if (!custom_ext_add(s
, context
, pkt
, x
, chainidx
, max_version
)) {
835 /* SSLfatal() already called */
839 for (i
= 0, thisexd
= ext_defs
; i
< OSSL_NELEM(ext_defs
); i
++, thisexd
++) {
840 EXT_RETURN (*construct
)(SSL
*s
, WPACKET
*pkt
, unsigned int context
,
841 X509
*x
, size_t chainidx
);
844 /* Skip if not relevant for our context */
845 if (!should_add_extension(s
, thisexd
->context
, context
, max_version
))
848 construct
= s
->server
? thisexd
->construct_stoc
849 : thisexd
->construct_ctos
;
851 if (construct
== NULL
)
854 ret
= construct(s
, pkt
, context
, x
, chainidx
);
855 if (ret
== EXT_RETURN_FAIL
) {
856 /* SSLfatal() already called */
859 if (ret
== EXT_RETURN_SENT
860 && (context
& (SSL_EXT_CLIENT_HELLO
861 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
862 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
)) != 0)
863 s
->ext
.extflags
[i
] |= SSL_EXT_FLAG_SENT
;
866 if (!WPACKET_close(pkt
)) {
867 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_CONSTRUCT_EXTENSIONS
,
868 ERR_R_INTERNAL_ERROR
);
876 * Built in extension finalisation and initialisation functions. All initialise
877 * or finalise the associated extension type for the given |context|. For
878 * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
879 * otherwise. These functions return 1 on success or 0 on failure.
882 static int final_renegotiate(SSL
*s
, unsigned int context
, int sent
)
886 * Check if we can connect to a server that doesn't support safe
889 if (!(s
->options
& SSL_OP_LEGACY_SERVER_CONNECT
)
890 && !(s
->options
& SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
)
892 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_RENEGOTIATE
,
893 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED
);
900 /* Need RI if renegotiating */
902 && !(s
->options
& SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
)
904 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_RENEGOTIATE
,
905 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED
);
913 static int init_server_name(SSL
*s
, unsigned int context
)
916 s
->servername_done
= 0;
918 OPENSSL_free(s
->ext
.hostname
);
919 s
->ext
.hostname
= NULL
;
925 static int final_server_name(SSL
*s
, unsigned int context
, int sent
)
927 int ret
= SSL_TLSEXT_ERR_NOACK
;
928 int altmp
= SSL_AD_UNRECOGNIZED_NAME
;
929 int was_ticket
= (SSL_get_options(s
) & SSL_OP_NO_TICKET
) == 0;
931 if (!ossl_assert(s
->ctx
!= NULL
) || !ossl_assert(s
->session_ctx
!= NULL
)) {
932 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
933 ERR_R_INTERNAL_ERROR
);
937 if (s
->ctx
->ext
.servername_cb
!= NULL
)
938 ret
= s
->ctx
->ext
.servername_cb(s
, &altmp
,
939 s
->ctx
->ext
.servername_arg
);
940 else if (s
->session_ctx
->ext
.servername_cb
!= NULL
)
941 ret
= s
->session_ctx
->ext
.servername_cb(s
, &altmp
,
942 s
->session_ctx
->ext
.servername_arg
);
945 * For servers, propagate the SNI hostname from the temporary
946 * storage in the SSL to the persistent SSL_SESSION, now that we
947 * know we accepted it.
948 * Clients make this copy when parsing the server's response to
949 * the extension, which is when they find out that the negotiation
953 if (sent
&& ret
== SSL_TLSEXT_ERR_OK
&& !s
->hit
) {
954 /* Only store the hostname in the session if we accepted it. */
955 OPENSSL_free(s
->session
->ext
.hostname
);
956 s
->session
->ext
.hostname
= OPENSSL_strdup(s
->ext
.hostname
);
957 if (s
->session
->ext
.hostname
== NULL
&& s
->ext
.hostname
!= NULL
) {
958 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
959 ERR_R_INTERNAL_ERROR
);
965 * If we switched contexts (whether here or in the client_hello callback),
966 * move the sess_accept increment from the session_ctx to the new
967 * context, to avoid the confusing situation of having sess_accept_good
968 * exceed sess_accept (zero) for the new context.
970 if (SSL_IS_FIRST_HANDSHAKE(s
) && s
->ctx
!= s
->session_ctx
) {
971 tsan_counter(&s
->ctx
->stats
.sess_accept
);
972 tsan_decr(&s
->session_ctx
->stats
.sess_accept
);
976 * If we're expecting to send a ticket, and tickets were previously enabled,
977 * and now tickets are disabled, then turn off expected ticket.
978 * Also, if this is not a resumption, create a new session ID
980 if (ret
== SSL_TLSEXT_ERR_OK
&& s
->ext
.ticket_expected
981 && was_ticket
&& (SSL_get_options(s
) & SSL_OP_NO_TICKET
) != 0) {
982 s
->ext
.ticket_expected
= 0;
984 SSL_SESSION
* ss
= SSL_get_session(s
);
987 OPENSSL_free(ss
->ext
.tick
);
990 ss
->ext
.tick_lifetime_hint
= 0;
991 ss
->ext
.tick_age_add
= 0;
992 if (!ssl_generate_session_id(s
, ss
)) {
993 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
994 ERR_R_INTERNAL_ERROR
);
998 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
999 ERR_R_INTERNAL_ERROR
);
1006 case SSL_TLSEXT_ERR_ALERT_FATAL
:
1007 SSLfatal(s
, altmp
, SSL_F_FINAL_SERVER_NAME
, SSL_R_CALLBACK_FAILED
);
1010 case SSL_TLSEXT_ERR_ALERT_WARNING
:
1011 /* TLSv1.3 doesn't have warning alerts so we suppress this */
1012 if (!SSL_IS_TLS13(s
))
1013 ssl3_send_alert(s
, SSL3_AL_WARNING
, altmp
);
1014 s
->servername_done
= 0;
1017 case SSL_TLSEXT_ERR_NOACK
:
1018 s
->servername_done
= 0;
1026 #ifndef OPENSSL_NO_EC
1027 static int final_ec_pt_formats(SSL
*s
, unsigned int context
, int sent
)
1029 unsigned long alg_k
, alg_a
;
1034 alg_k
= s
->s3
.tmp
.new_cipher
->algorithm_mkey
;
1035 alg_a
= s
->s3
.tmp
.new_cipher
->algorithm_auth
;
1038 * If we are client and using an elliptic curve cryptography cipher
1039 * suite, then if server returns an EC point formats lists extension it
1040 * must contain uncompressed.
1042 if (s
->ext
.ecpointformats
!= NULL
1043 && s
->ext
.ecpointformats_len
> 0
1044 && s
->ext
.peer_ecpointformats
!= NULL
1045 && s
->ext
.peer_ecpointformats_len
> 0
1046 && ((alg_k
& SSL_kECDHE
) || (alg_a
& SSL_aECDSA
))) {
1047 /* we are using an ECC cipher */
1049 unsigned char *list
= s
->ext
.peer_ecpointformats
;
1051 for (i
= 0; i
< s
->ext
.peer_ecpointformats_len
; i
++) {
1052 if (*list
++ == TLSEXT_ECPOINTFORMAT_uncompressed
)
1055 if (i
== s
->ext
.peer_ecpointformats_len
) {
1056 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_FINAL_EC_PT_FORMATS
,
1057 SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST
);
1066 static int init_session_ticket(SSL
*s
, unsigned int context
)
1069 s
->ext
.ticket_expected
= 0;
1074 #ifndef OPENSSL_NO_OCSP
1075 static int init_status_request(SSL
*s
, unsigned int context
)
1078 s
->ext
.status_type
= TLSEXT_STATUSTYPE_nothing
;
1081 * Ensure we get sensible values passed to tlsext_status_cb in the event
1082 * that we don't receive a status message
1084 OPENSSL_free(s
->ext
.ocsp
.resp
);
1085 s
->ext
.ocsp
.resp
= NULL
;
1086 s
->ext
.ocsp
.resp_len
= 0;
1093 #ifndef OPENSSL_NO_NEXTPROTONEG
1094 static int init_npn(SSL
*s
, unsigned int context
)
1102 static int init_alpn(SSL
*s
, unsigned int context
)
1104 OPENSSL_free(s
->s3
.alpn_selected
);
1105 s
->s3
.alpn_selected
= NULL
;
1106 s
->s3
.alpn_selected_len
= 0;
1108 OPENSSL_free(s
->s3
.alpn_proposed
);
1109 s
->s3
.alpn_proposed
= NULL
;
1110 s
->s3
.alpn_proposed_len
= 0;
1115 static int final_alpn(SSL
*s
, unsigned int context
, int sent
)
1117 if (!s
->server
&& !sent
&& s
->session
->ext
.alpn_selected
!= NULL
)
1118 s
->ext
.early_data_ok
= 0;
1120 if (!s
->server
|| !SSL_IS_TLS13(s
))
1124 * Call alpn_select callback if needed. Has to be done after SNI and
1125 * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
1126 * we also have to do this before we decide whether to accept early_data.
1127 * In TLSv1.3 we've already negotiated our cipher so we do this call now.
1128 * For < TLSv1.3 we defer it until after cipher negotiation.
1130 * On failure SSLfatal() already called.
1132 return tls_handle_alpn(s
);
1135 static int init_sig_algs(SSL
*s
, unsigned int context
)
1137 /* Clear any signature algorithms extension received */
1138 OPENSSL_free(s
->s3
.tmp
.peer_sigalgs
);
1139 s
->s3
.tmp
.peer_sigalgs
= NULL
;
1144 static int init_sig_algs_cert(SSL
*s
, unsigned int context
)
1146 /* Clear any signature algorithms extension received */
1147 OPENSSL_free(s
->s3
.tmp
.peer_cert_sigalgs
);
1148 s
->s3
.tmp
.peer_cert_sigalgs
= NULL
;
1153 #ifndef OPENSSL_NO_SRP
1154 static int init_srp(SSL
*s
, unsigned int context
)
1156 OPENSSL_free(s
->srp_ctx
.login
);
1157 s
->srp_ctx
.login
= NULL
;
1163 static int init_etm(SSL
*s
, unsigned int context
)
1170 static int init_ems(SSL
*s
, unsigned int context
)
1172 if (s
->s3
.flags
& TLS1_FLAGS_RECEIVED_EXTMS
) {
1173 s
->s3
.flags
&= ~TLS1_FLAGS_RECEIVED_EXTMS
;
1174 s
->s3
.flags
|= TLS1_FLAGS_REQUIRED_EXTMS
;
1180 static int final_ems(SSL
*s
, unsigned int context
, int sent
)
1183 * Check extended master secret extension is not dropped on
1186 if (!(s
->s3
.flags
& TLS1_FLAGS_RECEIVED_EXTMS
)
1187 && (s
->s3
.flags
& TLS1_FLAGS_REQUIRED_EXTMS
)) {
1188 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_EMS
,
1189 SSL_R_INCONSISTENT_EXTMS
);
1192 if (!s
->server
&& s
->hit
) {
1194 * Check extended master secret extension is consistent with
1197 if (!(s
->s3
.flags
& TLS1_FLAGS_RECEIVED_EXTMS
) !=
1198 !(s
->session
->flags
& SSL_SESS_FLAG_EXTMS
)) {
1199 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_EMS
,
1200 SSL_R_INCONSISTENT_EXTMS
);
1208 static int init_certificate_authorities(SSL
*s
, unsigned int context
)
1210 sk_X509_NAME_pop_free(s
->s3
.tmp
.peer_ca_names
, X509_NAME_free
);
1211 s
->s3
.tmp
.peer_ca_names
= NULL
;
1215 static EXT_RETURN
tls_construct_certificate_authorities(SSL
*s
, WPACKET
*pkt
,
1216 unsigned int context
,
1220 const STACK_OF(X509_NAME
) *ca_sk
= get_ca_names(s
);
1222 if (ca_sk
== NULL
|| sk_X509_NAME_num(ca_sk
) == 0)
1223 return EXT_RETURN_NOT_SENT
;
1225 if (!WPACKET_put_bytes_u16(pkt
, TLSEXT_TYPE_certificate_authorities
)
1226 || !WPACKET_start_sub_packet_u16(pkt
)) {
1227 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
1228 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES
,
1229 ERR_R_INTERNAL_ERROR
);
1230 return EXT_RETURN_FAIL
;
1233 if (!construct_ca_names(s
, ca_sk
, pkt
)) {
1234 /* SSLfatal() already called */
1235 return EXT_RETURN_FAIL
;
1238 if (!WPACKET_close(pkt
)) {
1239 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
1240 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES
,
1241 ERR_R_INTERNAL_ERROR
);
1242 return EXT_RETURN_FAIL
;
1245 return EXT_RETURN_SENT
;
1248 static int tls_parse_certificate_authorities(SSL
*s
, PACKET
*pkt
,
1249 unsigned int context
, X509
*x
,
1252 if (!parse_ca_names(s
, pkt
))
1254 if (PACKET_remaining(pkt
) != 0) {
1255 SSLfatal(s
, SSL_AD_DECODE_ERROR
,
1256 SSL_F_TLS_PARSE_CERTIFICATE_AUTHORITIES
, SSL_R_BAD_EXTENSION
);
1262 #ifndef OPENSSL_NO_SRTP
1263 static int init_srtp(SSL
*s
, unsigned int context
)
1266 s
->srtp_profile
= NULL
;
1272 static int final_sig_algs(SSL
*s
, unsigned int context
, int sent
)
1274 if (!sent
&& SSL_IS_TLS13(s
) && !s
->hit
) {
1275 SSLfatal(s
, TLS13_AD_MISSING_EXTENSION
, SSL_F_FINAL_SIG_ALGS
,
1276 SSL_R_MISSING_SIGALGS_EXTENSION
);
1283 static int final_key_share(SSL
*s
, unsigned int context
, int sent
)
1285 #if !defined(OPENSSL_NO_TLS1_3)
1286 if (!SSL_IS_TLS13(s
))
1289 /* Nothing to do for key_share in an HRR */
1290 if ((context
& SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
) != 0)
1297 * we have no key_share
1299 * (we are not resuming
1300 * OR the kex_mode doesn't allow non key_share resumes)
1307 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE
) == 0)) {
1308 /* Nothing left we can do - just fail */
1309 SSLfatal(s
, SSL_AD_MISSING_EXTENSION
, SSL_F_FINAL_KEY_SHARE
,
1310 SSL_R_NO_SUITABLE_KEY_SHARE
);
1318 * we have a suitable key_share
1321 * we are stateless AND we have no cookie
1323 * send a HelloRetryRequest
1326 * we didn't already send a HelloRetryRequest
1328 * the client sent a key_share extension
1330 * (we are not resuming
1331 * OR the kex_mode allows key_share resumes)
1333 * a shared group exists
1335 * send a HelloRetryRequest
1337 * we are not resuming
1339 * the kex_mode doesn't allow non key_share resumes
1343 * we are stateless AND we have no cookie
1345 * send a HelloRetryRequest
1348 if (s
->s3
.peer_tmp
!= NULL
) {
1349 /* We have a suitable key_share */
1350 if ((s
->s3
.flags
& TLS1_FLAGS_STATELESS
) != 0
1351 && !s
->ext
.cookieok
) {
1352 if (!ossl_assert(s
->hello_retry_request
== SSL_HRR_NONE
)) {
1354 * If we are stateless then we wouldn't know about any
1355 * previously sent HRR - so how can this be anything other
1358 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_KEY_SHARE
,
1359 ERR_R_INTERNAL_ERROR
);
1362 s
->hello_retry_request
= SSL_HRR_PENDING
;
1366 /* No suitable key_share */
1367 if (s
->hello_retry_request
== SSL_HRR_NONE
&& sent
1369 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE_DHE
)
1371 const uint16_t *pgroups
, *clntgroups
;
1372 size_t num_groups
, clnt_num_groups
, i
;
1373 unsigned int group_id
= 0;
1375 /* Check if a shared group exists */
1377 /* Get the clients list of supported groups. */
1378 tls1_get_peer_groups(s
, &clntgroups
, &clnt_num_groups
);
1379 tls1_get_supported_groups(s
, &pgroups
, &num_groups
);
1382 * Find the first group we allow that is also in client's list
1384 for (i
= 0; i
< num_groups
; i
++) {
1385 group_id
= pgroups
[i
];
1387 if (check_in_list(s
, group_id
, clntgroups
, clnt_num_groups
,
1392 if (i
< num_groups
) {
1393 /* A shared group exists so send a HelloRetryRequest */
1394 s
->s3
.group_id
= group_id
;
1395 s
->hello_retry_request
= SSL_HRR_PENDING
;
1400 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE
) == 0) {
1401 /* Nothing left we can do - just fail */
1402 SSLfatal(s
, sent
? SSL_AD_HANDSHAKE_FAILURE
1403 : SSL_AD_MISSING_EXTENSION
,
1404 SSL_F_FINAL_KEY_SHARE
, SSL_R_NO_SUITABLE_KEY_SHARE
);
1408 if ((s
->s3
.flags
& TLS1_FLAGS_STATELESS
) != 0
1409 && !s
->ext
.cookieok
) {
1410 if (!ossl_assert(s
->hello_retry_request
== SSL_HRR_NONE
)) {
1412 * If we are stateless then we wouldn't know about any
1413 * previously sent HRR - so how can this be anything other
1416 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_KEY_SHARE
,
1417 ERR_R_INTERNAL_ERROR
);
1420 s
->hello_retry_request
= SSL_HRR_PENDING
;
1426 * We have a key_share so don't send any more HelloRetryRequest
1429 if (s
->hello_retry_request
== SSL_HRR_PENDING
)
1430 s
->hello_retry_request
= SSL_HRR_COMPLETE
;
1433 * For a client side resumption with no key_share we need to generate
1434 * the handshake secret (otherwise this is done during key_share
1437 if (!sent
&& !tls13_generate_handshake_secret(s
, NULL
, 0)) {
1438 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_KEY_SHARE
,
1439 ERR_R_INTERNAL_ERROR
);
1443 #endif /* !defined(OPENSSL_NO_TLS1_3) */
1447 static int init_psk_kex_modes(SSL
*s
, unsigned int context
)
1449 s
->ext
.psk_kex_mode
= TLSEXT_KEX_MODE_FLAG_NONE
;
1453 int tls_psk_do_binder(SSL
*s
, const EVP_MD
*md
, const unsigned char *msgstart
,
1454 size_t binderoffset
, const unsigned char *binderin
,
1455 unsigned char *binderout
, SSL_SESSION
*sess
, int sign
,
1458 EVP_PKEY
*mackey
= NULL
;
1459 EVP_MD_CTX
*mctx
= NULL
;
1460 unsigned char hash
[EVP_MAX_MD_SIZE
], binderkey
[EVP_MAX_MD_SIZE
];
1461 unsigned char finishedkey
[EVP_MAX_MD_SIZE
], tmpbinder
[EVP_MAX_MD_SIZE
];
1462 unsigned char *early_secret
;
1463 #ifdef CHARSET_EBCDIC
1464 static const unsigned char resumption_label
[] = { 0x72, 0x65, 0x73, 0x20, 0x62, 0x69, 0x6E, 0x64, 0x65, 0x72, 0x00 };
1465 static const unsigned char external_label
[] = { 0x65, 0x78, 0x74, 0x20, 0x62, 0x69, 0x6E, 0x64, 0x65, 0x72, 0x00 };
1467 static const unsigned char resumption_label
[] = "res binder";
1468 static const unsigned char external_label
[] = "ext binder";
1470 const unsigned char *label
;
1471 size_t bindersize
, labelsize
, hashsize
;
1472 int hashsizei
= EVP_MD_size(md
);
1474 int usepskfored
= 0;
1476 /* Ensure cast to size_t is safe */
1477 if (!ossl_assert(hashsizei
>= 0)) {
1478 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1479 ERR_R_INTERNAL_ERROR
);
1482 hashsize
= (size_t)hashsizei
;
1485 && s
->early_data_state
== SSL_EARLY_DATA_CONNECTING
1486 && s
->session
->ext
.max_early_data
== 0
1487 && sess
->ext
.max_early_data
> 0)
1491 label
= external_label
;
1492 labelsize
= sizeof(external_label
) - 1;
1494 label
= resumption_label
;
1495 labelsize
= sizeof(resumption_label
) - 1;
1499 * Generate the early_secret. On the server side we've selected a PSK to
1500 * resume with (internal or external) so we always do this. On the client
1501 * side we do this for a non-external (i.e. resumption) PSK or external PSK
1502 * that will be used for early_data so that it is in place for sending early
1503 * data. For client side external PSK not being used for early_data we
1504 * generate it but store it away for later use.
1506 if (s
->server
|| !external
|| usepskfored
)
1507 early_secret
= (unsigned char *)s
->early_secret
;
1509 early_secret
= (unsigned char *)sess
->early_secret
;
1511 if (!tls13_generate_secret(s
, md
, NULL
, sess
->master_key
,
1512 sess
->master_key_length
, early_secret
)) {
1513 /* SSLfatal() already called */
1518 * Create the handshake hash for the binder key...the messages so far are
1521 mctx
= EVP_MD_CTX_new();
1523 || EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0
1524 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
1525 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1526 ERR_R_INTERNAL_ERROR
);
1530 /* Generate the binder key */
1531 if (!tls13_hkdf_expand(s
, md
, early_secret
, label
, labelsize
, hash
,
1532 hashsize
, binderkey
, hashsize
, 1)) {
1533 /* SSLfatal() already called */
1537 /* Generate the finished key */
1538 if (!tls13_derive_finishedkey(s
, md
, binderkey
, finishedkey
, hashsize
)) {
1539 /* SSLfatal() already called */
1543 if (EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0) {
1544 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1545 ERR_R_INTERNAL_ERROR
);
1550 * Get a hash of the ClientHello up to the start of the binders. If we are
1551 * following a HelloRetryRequest then this includes the hash of the first
1552 * ClientHello and the HelloRetryRequest itself.
1554 if (s
->hello_retry_request
== SSL_HRR_PENDING
) {
1559 hdatalen
= hdatalen_l
=
1560 BIO_get_mem_data(s
->s3
.handshake_buffer
, &hdata
);
1561 if (hdatalen_l
<= 0) {
1562 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1563 SSL_R_BAD_HANDSHAKE_LENGTH
);
1568 * For servers the handshake buffer data will include the second
1569 * ClientHello - which we don't want - so we need to take that bit off.
1572 PACKET hashprefix
, msg
;
1574 /* Find how many bytes are left after the first two messages */
1575 if (!PACKET_buf_init(&hashprefix
, hdata
, hdatalen
)
1576 || !PACKET_forward(&hashprefix
, 1)
1577 || !PACKET_get_length_prefixed_3(&hashprefix
, &msg
)
1578 || !PACKET_forward(&hashprefix
, 1)
1579 || !PACKET_get_length_prefixed_3(&hashprefix
, &msg
)) {
1580 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1581 ERR_R_INTERNAL_ERROR
);
1584 hdatalen
-= PACKET_remaining(&hashprefix
);
1587 if (EVP_DigestUpdate(mctx
, hdata
, hdatalen
) <= 0) {
1588 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1589 ERR_R_INTERNAL_ERROR
);
1594 if (EVP_DigestUpdate(mctx
, msgstart
, binderoffset
) <= 0
1595 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
1596 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1597 ERR_R_INTERNAL_ERROR
);
1601 mackey
= EVP_PKEY_new_raw_private_key_with_libctx(s
->ctx
->libctx
, "HMAC",
1605 if (mackey
== NULL
) {
1606 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1607 ERR_R_INTERNAL_ERROR
);
1612 binderout
= tmpbinder
;
1614 bindersize
= hashsize
;
1615 if (EVP_DigestSignInit_with_libctx(mctx
, NULL
, EVP_MD_name(md
),
1616 s
->ctx
->libctx
, s
->ctx
->propq
,
1618 || EVP_DigestSignUpdate(mctx
, hash
, hashsize
) <= 0
1619 || EVP_DigestSignFinal(mctx
, binderout
, &bindersize
) <= 0
1620 || bindersize
!= hashsize
) {
1621 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1622 ERR_R_INTERNAL_ERROR
);
1629 /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */
1630 ret
= (CRYPTO_memcmp(binderin
, binderout
, hashsize
) == 0);
1632 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_TLS_PSK_DO_BINDER
,
1633 SSL_R_BINDER_DOES_NOT_VERIFY
);
1637 OPENSSL_cleanse(binderkey
, sizeof(binderkey
));
1638 OPENSSL_cleanse(finishedkey
, sizeof(finishedkey
));
1639 EVP_PKEY_free(mackey
);
1640 EVP_MD_CTX_free(mctx
);
1645 static int final_early_data(SSL
*s
, unsigned int context
, int sent
)
1651 if (context
== SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
1653 && !s
->ext
.early_data_ok
) {
1655 * If we get here then the server accepted our early_data but we
1656 * later realised that it shouldn't have done (e.g. inconsistent
1659 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_FINAL_EARLY_DATA
,
1660 SSL_R_BAD_EARLY_DATA
);
1667 if (s
->max_early_data
== 0
1669 || s
->early_data_state
!= SSL_EARLY_DATA_ACCEPTING
1670 || !s
->ext
.early_data_ok
1671 || s
->hello_retry_request
!= SSL_HRR_NONE
1672 || (s
->allow_early_data_cb
!= NULL
1673 && !s
->allow_early_data_cb(s
,
1674 s
->allow_early_data_cb_data
))) {
1675 s
->ext
.early_data
= SSL_EARLY_DATA_REJECTED
;
1677 s
->ext
.early_data
= SSL_EARLY_DATA_ACCEPTED
;
1679 if (!tls13_change_cipher_state(s
,
1680 SSL3_CC_EARLY
| SSL3_CHANGE_CIPHER_SERVER_READ
)) {
1681 /* SSLfatal() already called */
1689 static int final_maxfragmentlen(SSL
*s
, unsigned int context
, int sent
)
1692 * Session resumption on server-side with MFL extension active
1693 * BUT MFL extension packet was not resent (i.e. sent == 0)
1695 if (s
->server
&& s
->hit
&& USE_MAX_FRAGMENT_LENGTH_EXT(s
->session
)
1697 SSLfatal(s
, SSL_AD_MISSING_EXTENSION
, SSL_F_FINAL_MAXFRAGMENTLEN
,
1698 SSL_R_BAD_EXTENSION
);
1702 /* Current SSL buffer is lower than requested MFL */
1703 if (s
->session
&& USE_MAX_FRAGMENT_LENGTH_EXT(s
->session
)
1704 && s
->max_send_fragment
< GET_MAX_FRAGMENT_LENGTH(s
->session
))
1705 /* trigger a larger buffer reallocation */
1706 if (!ssl3_setup_buffers(s
)) {
1707 /* SSLfatal() already called */
1714 static int init_post_handshake_auth(SSL
*s
, unsigned int context
)
1716 s
->post_handshake_auth
= SSL_PHA_NONE
;