2 * Copyright 2016-2022 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
10 #if defined(__TANDEM) && defined(_SPT_MODEL_)
11 # include <spthread.h>
12 # include <spt_extensions.h> /* timeval */
16 #include "internal/nelem.h"
17 #include "internal/cryptlib.h"
18 #include "../ssl_local.h"
19 #include "statem_local.h"
21 static int final_renegotiate(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
22 static int init_server_name(SSL_CONNECTION
*s
, unsigned int context
);
23 static int final_server_name(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
24 static int final_ec_pt_formats(SSL_CONNECTION
*s
, unsigned int context
,
26 static int init_session_ticket(SSL_CONNECTION
*s
, unsigned int context
);
27 #ifndef OPENSSL_NO_OCSP
28 static int init_status_request(SSL_CONNECTION
*s
, unsigned int context
);
30 #ifndef OPENSSL_NO_NEXTPROTONEG
31 static int init_npn(SSL_CONNECTION
*s
, unsigned int context
);
33 static int init_alpn(SSL_CONNECTION
*s
, unsigned int context
);
34 static int final_alpn(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
35 static int init_sig_algs_cert(SSL_CONNECTION
*s
, unsigned int context
);
36 static int init_sig_algs(SSL_CONNECTION
*s
, unsigned int context
);
37 static int init_certificate_authorities(SSL_CONNECTION
*s
,
38 unsigned int context
);
39 static EXT_RETURN
tls_construct_certificate_authorities(SSL_CONNECTION
*s
,
44 static int tls_parse_certificate_authorities(SSL_CONNECTION
*s
, PACKET
*pkt
,
45 unsigned int context
, X509
*x
,
47 #ifndef OPENSSL_NO_SRP
48 static int init_srp(SSL_CONNECTION
*s
, unsigned int context
);
50 static int init_ec_point_formats(SSL_CONNECTION
*s
, unsigned int context
);
51 static int init_etm(SSL_CONNECTION
*s
, unsigned int context
);
52 static int init_ems(SSL_CONNECTION
*s
, unsigned int context
);
53 static int final_ems(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
54 static int init_psk_kex_modes(SSL_CONNECTION
*s
, unsigned int context
);
55 static int final_key_share(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
56 #ifndef OPENSSL_NO_SRTP
57 static int init_srtp(SSL_CONNECTION
*s
, unsigned int context
);
59 static int final_sig_algs(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
60 static int final_early_data(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
61 static int final_maxfragmentlen(SSL_CONNECTION
*s
, unsigned int context
,
63 static int init_post_handshake_auth(SSL_CONNECTION
*s
, unsigned int context
);
64 static int final_psk(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
66 /* Structure to define a built-in extension */
67 typedef struct extensions_definition_st
{
68 /* The defined type for the extension */
71 * The context that this extension applies to, e.g. what messages and
76 * Initialise extension before parsing. Always called for relevant contexts
77 * even if extension not present
79 int (*init
)(SSL_CONNECTION
*s
, unsigned int context
);
80 /* Parse extension sent from client to server */
81 int (*parse_ctos
)(SSL_CONNECTION
*s
, PACKET
*pkt
, unsigned int context
,
82 X509
*x
, size_t chainidx
);
83 /* Parse extension send from server to client */
84 int (*parse_stoc
)(SSL_CONNECTION
*s
, PACKET
*pkt
, unsigned int context
,
85 X509
*x
, size_t chainidx
);
86 /* Construct extension sent from server to client */
87 EXT_RETURN (*construct_stoc
)(SSL_CONNECTION
*s
, WPACKET
*pkt
,
89 X509
*x
, size_t chainidx
);
90 /* Construct extension sent from client to server */
91 EXT_RETURN (*construct_ctos
)(SSL_CONNECTION
*s
, WPACKET
*pkt
,
93 X509
*x
, size_t chainidx
);
95 * Finalise extension after parsing. Always called where an extensions was
96 * initialised even if the extension was not present. |sent| is set to 1 if
97 * the extension was seen, or 0 otherwise.
99 int (*final
)(SSL_CONNECTION
*s
, unsigned int context
, int sent
);
100 } EXTENSION_DEFINITION
;
103 * Definitions of all built-in extensions. NOTE: Changes in the number or order
104 * of these extensions should be mirrored with equivalent changes to the
105 * indexes ( TLSEXT_IDX_* ) defined in ssl_local.h.
106 * Each extension has an initialiser, a client and
107 * server side parser and a finaliser. The initialiser is called (if the
108 * extension is relevant to the given context) even if we did not see the
109 * extension in the message that we received. The parser functions are only
110 * called if we see the extension in the message. The finalisers are always
111 * called if the initialiser was called.
112 * There are also server and client side constructor functions which are always
113 * called during message construction if the extension is relevant for the
115 * The initialisation, parsing, finalisation and construction functions are
116 * always called in the order defined in this list. Some extensions may depend
117 * on others having been processed first, so the order of this list is
119 * The extension context is defined by a series of flags which specify which
120 * messages the extension is relevant to. These flags also specify whether the
121 * extension is relevant to a particular protocol or protocol version.
123 * NOTE: WebSphere Application Server 7+ cannot handle empty extensions at
124 * the end, keep these extensions before signature_algorithm.
126 #define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL }
127 static const EXTENSION_DEFINITION ext_defs
[] = {
129 TLSEXT_TYPE_renegotiate
,
130 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
131 | SSL_EXT_SSL3_ALLOWED
| SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
132 NULL
, tls_parse_ctos_renegotiate
, tls_parse_stoc_renegotiate
,
133 tls_construct_stoc_renegotiate
, tls_construct_ctos_renegotiate
,
137 TLSEXT_TYPE_server_name
,
138 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
139 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
141 tls_parse_ctos_server_name
, tls_parse_stoc_server_name
,
142 tls_construct_stoc_server_name
, tls_construct_ctos_server_name
,
146 TLSEXT_TYPE_max_fragment_length
,
147 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
148 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
149 NULL
, tls_parse_ctos_maxfragmentlen
, tls_parse_stoc_maxfragmentlen
,
150 tls_construct_stoc_maxfragmentlen
, tls_construct_ctos_maxfragmentlen
,
153 #ifndef OPENSSL_NO_SRP
156 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
157 init_srp
, tls_parse_ctos_srp
, NULL
, NULL
, tls_construct_ctos_srp
, NULL
163 TLSEXT_TYPE_ec_point_formats
,
164 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
165 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
166 init_ec_point_formats
, tls_parse_ctos_ec_pt_formats
, tls_parse_stoc_ec_pt_formats
,
167 tls_construct_stoc_ec_pt_formats
, tls_construct_ctos_ec_pt_formats
,
172 * "supported_groups" is spread across several specifications.
173 * It was originally specified as "elliptic_curves" in RFC 4492,
174 * and broadened to include named FFDH groups by RFC 7919.
175 * Both RFCs 4492 and 7919 do not include a provision for the server
176 * to indicate to the client the complete list of groups supported
177 * by the server, with the server instead just indicating the
178 * selected group for this connection in the ServerKeyExchange
179 * message. TLS 1.3 adds a scheme for the server to indicate
180 * to the client its list of supported groups in the
181 * EncryptedExtensions message, but none of the relevant
182 * specifications permit sending supported_groups in the ServerHello.
183 * Nonetheless (possibly due to the close proximity to the
184 * "ec_point_formats" extension, which is allowed in the ServerHello),
185 * there are several servers that send this extension in the
186 * ServerHello anyway. Up to and including the 1.1.0 release,
187 * we did not check for the presence of nonpermitted extensions,
188 * so to avoid a regression, we must permit this extension in the
189 * TLS 1.2 ServerHello as well.
191 * Note that there is no tls_parse_stoc_supported_groups function,
192 * so we do not perform any additional parsing, validation, or
193 * processing on the server's group list -- this is just a minimal
194 * change to preserve compatibility with these misbehaving servers.
196 TLSEXT_TYPE_supported_groups
,
197 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
198 | SSL_EXT_TLS1_2_SERVER_HELLO
,
199 NULL
, tls_parse_ctos_supported_groups
, NULL
,
200 tls_construct_stoc_supported_groups
,
201 tls_construct_ctos_supported_groups
, NULL
204 TLSEXT_TYPE_session_ticket
,
205 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
206 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
207 init_session_ticket
, tls_parse_ctos_session_ticket
,
208 tls_parse_stoc_session_ticket
, tls_construct_stoc_session_ticket
,
209 tls_construct_ctos_session_ticket
, NULL
211 #ifndef OPENSSL_NO_OCSP
213 TLSEXT_TYPE_status_request
,
214 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
215 | SSL_EXT_TLS1_3_CERTIFICATE
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
216 init_status_request
, tls_parse_ctos_status_request
,
217 tls_parse_stoc_status_request
, tls_construct_stoc_status_request
,
218 tls_construct_ctos_status_request
, NULL
223 #ifndef OPENSSL_NO_NEXTPROTONEG
225 TLSEXT_TYPE_next_proto_neg
,
226 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
227 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
228 init_npn
, tls_parse_ctos_npn
, tls_parse_stoc_npn
,
229 tls_construct_stoc_next_proto_neg
, tls_construct_ctos_npn
, NULL
236 * Must appear in this list after server_name so that finalisation
237 * happens after server_name callbacks
239 TLSEXT_TYPE_application_layer_protocol_negotiation
,
240 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
241 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
242 init_alpn
, tls_parse_ctos_alpn
, tls_parse_stoc_alpn
,
243 tls_construct_stoc_alpn
, tls_construct_ctos_alpn
, final_alpn
245 #ifndef OPENSSL_NO_SRTP
247 TLSEXT_TYPE_use_srtp
,
248 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
249 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
| SSL_EXT_DTLS_ONLY
,
250 init_srtp
, tls_parse_ctos_use_srtp
, tls_parse_stoc_use_srtp
,
251 tls_construct_stoc_use_srtp
, tls_construct_ctos_use_srtp
, NULL
257 TLSEXT_TYPE_encrypt_then_mac
,
258 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
259 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
260 init_etm
, tls_parse_ctos_etm
, tls_parse_stoc_etm
,
261 tls_construct_stoc_etm
, tls_construct_ctos_etm
, NULL
263 #ifndef OPENSSL_NO_CT
265 TLSEXT_TYPE_signed_certificate_timestamp
,
266 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
267 | SSL_EXT_TLS1_3_CERTIFICATE
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
270 * No server side support for this, but can be provided by a custom
271 * extension. This is an exception to the rule that custom extensions
272 * cannot override built in ones.
274 NULL
, tls_parse_stoc_sct
, NULL
, tls_construct_ctos_sct
, NULL
280 TLSEXT_TYPE_extended_master_secret
,
281 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
282 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
283 init_ems
, tls_parse_ctos_ems
, tls_parse_stoc_ems
,
284 tls_construct_stoc_ems
, tls_construct_ctos_ems
, final_ems
287 TLSEXT_TYPE_signature_algorithms_cert
,
288 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
289 init_sig_algs_cert
, tls_parse_ctos_sig_algs_cert
,
290 tls_parse_ctos_sig_algs_cert
,
291 /* We do not generate signature_algorithms_cert at present. */
295 TLSEXT_TYPE_post_handshake_auth
,
296 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ONLY
,
297 init_post_handshake_auth
,
298 tls_parse_ctos_post_handshake_auth
, NULL
,
299 NULL
, tls_construct_ctos_post_handshake_auth
,
303 TLSEXT_TYPE_signature_algorithms
,
304 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
305 init_sig_algs
, tls_parse_ctos_sig_algs
,
306 tls_parse_ctos_sig_algs
, tls_construct_ctos_sig_algs
,
307 tls_construct_ctos_sig_algs
, final_sig_algs
310 TLSEXT_TYPE_supported_versions
,
311 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
312 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
,
314 /* Processed inline as part of version selection */
315 NULL
, tls_parse_stoc_supported_versions
,
316 tls_construct_stoc_supported_versions
,
317 tls_construct_ctos_supported_versions
, NULL
320 TLSEXT_TYPE_psk_kex_modes
,
321 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
322 | SSL_EXT_TLS1_3_ONLY
,
323 init_psk_kex_modes
, tls_parse_ctos_psk_kex_modes
, NULL
, NULL
,
324 tls_construct_ctos_psk_kex_modes
, NULL
328 * Must be in this list after supported_groups. We need that to have
329 * been parsed before we do this one.
331 TLSEXT_TYPE_key_share
,
332 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
333 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
334 | SSL_EXT_TLS1_3_ONLY
,
335 NULL
, tls_parse_ctos_key_share
, tls_parse_stoc_key_share
,
336 tls_construct_stoc_key_share
, tls_construct_ctos_key_share
,
340 /* Must be after key_share */
342 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
343 | SSL_EXT_TLS_IMPLEMENTATION_ONLY
| SSL_EXT_TLS1_3_ONLY
,
344 NULL
, tls_parse_ctos_cookie
, tls_parse_stoc_cookie
,
345 tls_construct_stoc_cookie
, tls_construct_ctos_cookie
, NULL
349 * Special unsolicited ServerHello extension only used when
350 * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set. We allow it in a ClientHello but
353 TLSEXT_TYPE_cryptopro_bug
,
354 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
355 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
356 NULL
, NULL
, NULL
, tls_construct_stoc_cryptopro_bug
, NULL
, NULL
359 TLSEXT_TYPE_early_data
,
360 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
361 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
| SSL_EXT_TLS1_3_ONLY
,
362 NULL
, tls_parse_ctos_early_data
, tls_parse_stoc_early_data
,
363 tls_construct_stoc_early_data
, tls_construct_ctos_early_data
,
367 TLSEXT_TYPE_certificate_authorities
,
368 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
369 | SSL_EXT_TLS1_3_ONLY
,
370 init_certificate_authorities
,
371 tls_parse_certificate_authorities
, tls_parse_certificate_authorities
,
372 tls_construct_certificate_authorities
,
373 tls_construct_certificate_authorities
, NULL
,
376 /* Must be immediately before pre_shared_key */
378 SSL_EXT_CLIENT_HELLO
,
380 /* We send this, but don't read it */
381 NULL
, NULL
, NULL
, tls_construct_ctos_padding
, NULL
384 /* Required by the TLSv1.3 spec to always be the last extension */
386 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
387 | SSL_EXT_TLS_IMPLEMENTATION_ONLY
| SSL_EXT_TLS1_3_ONLY
,
388 NULL
, tls_parse_ctos_psk
, tls_parse_stoc_psk
, tls_construct_stoc_psk
,
389 tls_construct_ctos_psk
, final_psk
393 /* Check whether an extension's context matches the current context */
394 static int validate_context(SSL_CONNECTION
*s
, unsigned int extctx
,
395 unsigned int thisctx
)
397 /* Check we're allowed to use this extension in this context */
398 if ((thisctx
& extctx
) == 0)
401 if (SSL_CONNECTION_IS_DTLS(s
)) {
402 if ((extctx
& SSL_EXT_TLS_ONLY
) != 0)
404 } else if ((extctx
& SSL_EXT_DTLS_ONLY
) != 0) {
411 int tls_validate_all_contexts(SSL_CONNECTION
*s
, unsigned int thisctx
,
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_CONNECTION
*s
, unsigned int context
,
457 unsigned int type
, custom_ext_methods
*meths
,
458 RAW_EXTENSION
*rawexlist
, 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_CONNECTION
*s
, unsigned int extctx
,
505 unsigned int thisctx
)
510 * For HRR we haven't selected the version yet but we know it will be
513 if ((thisctx
& SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
) != 0)
516 is_tls13
= SSL_CONNECTION_IS_TLS13(s
);
518 if ((SSL_CONNECTION_IS_DTLS(s
)
519 && (extctx
& SSL_EXT_TLS_IMPLEMENTATION_ONLY
) != 0)
520 || (s
->version
== SSL3_VERSION
521 && (extctx
& SSL_EXT_SSL3_ALLOWED
) == 0)
523 * Note that SSL_IS_TLS13() means "TLS 1.3 has been negotiated",
524 * which is never true when generating the ClientHello.
525 * However, version negotiation *has* occurred by the time the
526 * ClientHello extensions are being parsed.
527 * Be careful to allow TLS 1.3-only extensions when generating
530 || (is_tls13
&& (extctx
& SSL_EXT_TLS1_2_AND_BELOW_ONLY
) != 0)
531 || (!is_tls13
&& (extctx
& SSL_EXT_TLS1_3_ONLY
) != 0
532 && (thisctx
& SSL_EXT_CLIENT_HELLO
) == 0)
533 || (s
->server
&& !is_tls13
&& (extctx
& SSL_EXT_TLS1_3_ONLY
) != 0)
534 || (s
->hit
&& (extctx
& SSL_EXT_IGNORE_ON_RESUMPTION
) != 0))
540 * Gather a list of all the extensions from the data in |packet]. |context|
541 * tells us which message this extension is for. The raw extension data is
542 * stored in |*res| on success. We don't actually process the content of the
543 * extensions yet, except to check their types. This function also runs the
544 * initialiser functions for all known extensions if |init| is nonzero (whether
545 * we have collected them or not). If successful the caller is responsible for
546 * freeing the contents of |*res|.
548 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
549 * more than one extension of the same type in a ClientHello or ServerHello.
550 * This function returns 1 if all extensions are unique and we have parsed their
551 * types, and 0 if the extensions contain duplicates, could not be successfully
552 * found, or an internal error occurred. We only check duplicates for
553 * extensions that we know about. We ignore others.
555 int tls_collect_extensions(SSL_CONNECTION
*s
, PACKET
*packet
,
556 unsigned int context
,
557 RAW_EXTENSION
**res
, size_t *len
, int init
)
559 PACKET extensions
= *packet
;
562 custom_ext_methods
*exts
= &s
->cert
->custext
;
563 RAW_EXTENSION
*raw_extensions
= NULL
;
564 const EXTENSION_DEFINITION
*thisexd
;
569 * Initialise server side custom extensions. Client side is done during
570 * construction of extensions for the ClientHello.
572 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0)
573 custom_ext_init(&s
->cert
->custext
);
575 num_exts
= OSSL_NELEM(ext_defs
) + (exts
!= NULL
? exts
->meths_count
: 0);
576 raw_extensions
= OPENSSL_zalloc(num_exts
* sizeof(*raw_extensions
));
577 if (raw_extensions
== NULL
) {
578 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_MALLOC_FAILURE
);
583 while (PACKET_remaining(&extensions
) > 0) {
584 unsigned int type
, idx
;
586 RAW_EXTENSION
*thisex
;
588 if (!PACKET_get_net_2(&extensions
, &type
) ||
589 !PACKET_get_length_prefixed_2(&extensions
, &extension
)) {
590 SSLfatal(s
, SSL_AD_DECODE_ERROR
, 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_R_BAD_EXTENSION
);
606 idx
= thisex
- raw_extensions
;
608 * Check that we requested this extension (if appropriate). Requests can
609 * be sent in the ClientHello and CertificateRequest. Unsolicited
610 * extensions can be sent in the NewSessionTicket. We only do this for
611 * the built-in extensions. Custom extensions have a different but
612 * similar check elsewhere.
614 * - The HRR cookie extension is unsolicited
615 * - The renegotiate extension is unsolicited (the client signals
616 * support via an SCSV)
617 * - The signed_certificate_timestamp extension can be provided by a
618 * custom extension or by the built-in version. We let the extension
619 * itself handle unsolicited response checks.
621 if (idx
< OSSL_NELEM(ext_defs
)
622 && (context
& (SSL_EXT_CLIENT_HELLO
623 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
624 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
)) == 0
625 && type
!= TLSEXT_TYPE_cookie
626 && type
!= TLSEXT_TYPE_renegotiate
627 && type
!= TLSEXT_TYPE_signed_certificate_timestamp
628 && (s
->ext
.extflags
[idx
] & SSL_EXT_FLAG_SENT
) == 0
629 #ifndef OPENSSL_NO_GOST
630 && !((context
& SSL_EXT_TLS1_2_SERVER_HELLO
) != 0
631 && type
== TLSEXT_TYPE_cryptopro_bug
)
634 SSLfatal(s
, SSL_AD_UNSUPPORTED_EXTENSION
,
635 SSL_R_UNSOLICITED_EXTENSION
);
638 if (thisex
!= NULL
) {
639 thisex
->data
= extension
;
642 thisex
->received_order
= i
++;
644 s
->ext
.debug_cb(SSL_CONNECTION_GET_SSL(s
), !s
->server
,
645 thisex
->type
, PACKET_data(&thisex
->data
),
646 PACKET_remaining(&thisex
->data
),
653 * Initialise all known extensions relevant to this context,
654 * whether we have found them or not
656 for (thisexd
= ext_defs
, i
= 0; i
< OSSL_NELEM(ext_defs
);
658 if (thisexd
->init
!= NULL
&& (thisexd
->context
& context
) != 0
659 && extension_is_relevant(s
, thisexd
->context
, context
)
660 && !thisexd
->init(s
, context
)) {
661 /* SSLfatal() already called */
667 *res
= raw_extensions
;
673 OPENSSL_free(raw_extensions
);
678 * Runs the parser for a given extension with index |idx|. |exts| contains the
679 * list of all parsed extensions previously collected by
680 * tls_collect_extensions(). The parser is only run if it is applicable for the
681 * given |context| and the parser has not already been run. If this is for a
682 * Certificate message, then we also provide the parser with the relevant
683 * Certificate |x| and its position in the |chainidx| with 0 being the first
684 * Certificate. Returns 1 on success or 0 on failure. If an extension is not
685 * present this counted as success.
687 int tls_parse_extension(SSL_CONNECTION
*s
, TLSEXT_INDEX idx
, int context
,
688 RAW_EXTENSION
*exts
, X509
*x
, size_t chainidx
)
690 RAW_EXTENSION
*currext
= &exts
[idx
];
691 int (*parser
)(SSL_CONNECTION
*s
, PACKET
*pkt
, unsigned int context
, X509
*x
,
692 size_t chainidx
) = NULL
;
694 /* Skip if the extension is not present */
695 if (!currext
->present
)
698 /* Skip if we've already parsed this extension */
704 if (idx
< OSSL_NELEM(ext_defs
)) {
705 /* We are handling a built-in extension */
706 const EXTENSION_DEFINITION
*extdef
= &ext_defs
[idx
];
708 /* Check if extension is defined for our protocol. If not, skip */
709 if (!extension_is_relevant(s
, extdef
->context
, context
))
712 parser
= s
->server
? extdef
->parse_ctos
: extdef
->parse_stoc
;
715 return parser(s
, &currext
->data
, context
, x
, chainidx
);
718 * If the parser is NULL we fall through to the custom extension
723 /* Parse custom extensions */
724 return custom_ext_parse(s
, context
, currext
->type
,
725 PACKET_data(&currext
->data
),
726 PACKET_remaining(&currext
->data
),
731 * Parse all remaining extensions that have not yet been parsed. Also calls the
732 * finalisation for all extensions at the end if |fin| is nonzero, whether we
733 * collected them or not. Returns 1 for success or 0 for failure. If we are
734 * working on a Certificate message then we also pass the Certificate |x| and
735 * its position in the |chainidx|, with 0 being the first certificate.
737 int tls_parse_all_extensions(SSL_CONNECTION
*s
, int context
,
738 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_CONNECTION
*s
, unsigned int extctx
,
774 unsigned int thisctx
, int max_version
)
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_CONNECTION_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_CONNECTION
*s
, WPACKET
*pkt
,
799 unsigned int context
,
800 X509
*x
, size_t chainidx
)
803 int min_version
, max_version
= 0, reason
;
804 const EXTENSION_DEFINITION
*thisexd
;
806 if (!WPACKET_start_sub_packet_u16(pkt
)
808 * If extensions are of zero length then we don't even add the
809 * extensions length bytes to a ClientHello/ServerHello
813 (SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
)) != 0
814 && !WPACKET_set_flags(pkt
,
815 WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH
))) {
816 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, 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
, reason
);
828 /* Add custom extensions first */
829 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0) {
830 /* On the server side with initialise during ClientHello parsing */
831 custom_ext_init(&s
->cert
->custext
);
833 if (!custom_ext_add(s
, context
, pkt
, x
, chainidx
, max_version
)) {
834 /* SSLfatal() already called */
838 for (i
= 0, thisexd
= ext_defs
; i
< OSSL_NELEM(ext_defs
); i
++, thisexd
++) {
839 EXT_RETURN (*construct
)(SSL_CONNECTION
*s
, WPACKET
*pkt
,
840 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
, ERR_R_INTERNAL_ERROR
);
875 * Built in extension finalisation and initialisation functions. All initialise
876 * or finalise the associated extension type for the given |context|. For
877 * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
878 * otherwise. These functions return 1 on success or 0 on failure.
881 static int final_renegotiate(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
885 * Check if we can connect to a server that doesn't support safe
888 if (!(s
->options
& SSL_OP_LEGACY_SERVER_CONNECT
)
889 && !(s
->options
& SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
)
891 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
,
892 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED
);
899 /* Need RI if renegotiating */
901 && !(s
->options
& SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
)
903 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
,
904 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED
);
912 static ossl_inline
void ssl_tsan_decr(const SSL_CTX
*ctx
,
913 TSAN_QUALIFIER
int *stat
)
915 if (ssl_tsan_lock(ctx
)) {
917 ssl_tsan_unlock(ctx
);
921 static int init_server_name(SSL_CONNECTION
*s
, unsigned int context
)
924 s
->servername_done
= 0;
926 OPENSSL_free(s
->ext
.hostname
);
927 s
->ext
.hostname
= NULL
;
933 static int final_server_name(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
935 int ret
= SSL_TLSEXT_ERR_NOACK
;
936 int altmp
= SSL_AD_UNRECOGNIZED_NAME
;
937 SSL
*ssl
= SSL_CONNECTION_GET_SSL(s
);
938 SSL_CTX
*sctx
= SSL_CONNECTION_GET_CTX(s
);
939 int was_ticket
= (SSL_get_options(ssl
) & SSL_OP_NO_TICKET
) == 0;
941 if (!ossl_assert(sctx
!= NULL
) || !ossl_assert(s
->session_ctx
!= NULL
)) {
942 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
946 if (sctx
->ext
.servername_cb
!= NULL
)
947 ret
= sctx
->ext
.servername_cb(ssl
, &altmp
,
948 sctx
->ext
.servername_arg
);
949 else if (s
->session_ctx
->ext
.servername_cb
!= NULL
)
950 ret
= s
->session_ctx
->ext
.servername_cb(ssl
, &altmp
,
951 s
->session_ctx
->ext
.servername_arg
);
954 * For servers, propagate the SNI hostname from the temporary
955 * storage in the SSL to the persistent SSL_SESSION, now that we
956 * know we accepted it.
957 * Clients make this copy when parsing the server's response to
958 * the extension, which is when they find out that the negotiation
962 if (sent
&& ret
== SSL_TLSEXT_ERR_OK
&& !s
->hit
) {
963 /* Only store the hostname in the session if we accepted it. */
964 OPENSSL_free(s
->session
->ext
.hostname
);
965 s
->session
->ext
.hostname
= OPENSSL_strdup(s
->ext
.hostname
);
966 if (s
->session
->ext
.hostname
== NULL
&& s
->ext
.hostname
!= NULL
) {
967 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
973 * If we switched contexts (whether here or in the client_hello callback),
974 * move the sess_accept increment from the session_ctx to the new
975 * context, to avoid the confusing situation of having sess_accept_good
976 * exceed sess_accept (zero) for the new context.
978 if (SSL_IS_FIRST_HANDSHAKE(s
) && sctx
!= s
->session_ctx
979 && s
->hello_retry_request
== SSL_HRR_NONE
) {
980 ssl_tsan_counter(sctx
, &sctx
->stats
.sess_accept
);
981 ssl_tsan_decr(s
->session_ctx
, &s
->session_ctx
->stats
.sess_accept
);
985 * If we're expecting to send a ticket, and tickets were previously enabled,
986 * and now tickets are disabled, then turn off expected ticket.
987 * Also, if this is not a resumption, create a new session ID
989 if (ret
== SSL_TLSEXT_ERR_OK
&& s
->ext
.ticket_expected
990 && was_ticket
&& (SSL_get_options(ssl
) & SSL_OP_NO_TICKET
) != 0) {
991 s
->ext
.ticket_expected
= 0;
993 SSL_SESSION
* ss
= SSL_get_session(ssl
);
996 OPENSSL_free(ss
->ext
.tick
);
999 ss
->ext
.tick_lifetime_hint
= 0;
1000 ss
->ext
.tick_age_add
= 0;
1001 if (!ssl_generate_session_id(s
, ss
)) {
1002 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1006 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1013 case SSL_TLSEXT_ERR_ALERT_FATAL
:
1014 SSLfatal(s
, altmp
, SSL_R_CALLBACK_FAILED
);
1017 case SSL_TLSEXT_ERR_ALERT_WARNING
:
1018 /* TLSv1.3 doesn't have warning alerts so we suppress this */
1019 if (!SSL_CONNECTION_IS_TLS13(s
))
1020 ssl3_send_alert(s
, SSL3_AL_WARNING
, altmp
);
1021 s
->servername_done
= 0;
1024 case SSL_TLSEXT_ERR_NOACK
:
1025 s
->servername_done
= 0;
1033 static int final_ec_pt_formats(SSL_CONNECTION
*s
, unsigned int context
,
1036 unsigned long alg_k
, alg_a
;
1041 alg_k
= s
->s3
.tmp
.new_cipher
->algorithm_mkey
;
1042 alg_a
= s
->s3
.tmp
.new_cipher
->algorithm_auth
;
1045 * If we are client and using an elliptic curve cryptography cipher
1046 * suite, then if server returns an EC point formats lists extension it
1047 * must contain uncompressed.
1049 if (s
->ext
.ecpointformats
!= NULL
1050 && s
->ext
.ecpointformats_len
> 0
1051 && s
->ext
.peer_ecpointformats
!= NULL
1052 && s
->ext
.peer_ecpointformats_len
> 0
1053 && ((alg_k
& SSL_kECDHE
) || (alg_a
& SSL_aECDSA
))) {
1054 /* we are using an ECC cipher */
1056 unsigned char *list
= s
->ext
.peer_ecpointformats
;
1058 for (i
= 0; i
< s
->ext
.peer_ecpointformats_len
; i
++) {
1059 if (*list
++ == TLSEXT_ECPOINTFORMAT_uncompressed
)
1062 if (i
== s
->ext
.peer_ecpointformats_len
) {
1063 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
,
1064 SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST
);
1072 static int init_session_ticket(SSL_CONNECTION
*s
, unsigned int context
)
1075 s
->ext
.ticket_expected
= 0;
1080 #ifndef OPENSSL_NO_OCSP
1081 static int init_status_request(SSL_CONNECTION
*s
, unsigned int context
)
1084 s
->ext
.status_type
= TLSEXT_STATUSTYPE_nothing
;
1087 * Ensure we get sensible values passed to tlsext_status_cb in the event
1088 * that we don't receive a status message
1090 OPENSSL_free(s
->ext
.ocsp
.resp
);
1091 s
->ext
.ocsp
.resp
= NULL
;
1092 s
->ext
.ocsp
.resp_len
= 0;
1099 #ifndef OPENSSL_NO_NEXTPROTONEG
1100 static int init_npn(SSL_CONNECTION
*s
, unsigned int context
)
1108 static int init_alpn(SSL_CONNECTION
*s
, unsigned int context
)
1110 OPENSSL_free(s
->s3
.alpn_selected
);
1111 s
->s3
.alpn_selected
= NULL
;
1112 s
->s3
.alpn_selected_len
= 0;
1114 OPENSSL_free(s
->s3
.alpn_proposed
);
1115 s
->s3
.alpn_proposed
= NULL
;
1116 s
->s3
.alpn_proposed_len
= 0;
1121 static int final_alpn(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
1123 if (!s
->server
&& !sent
&& s
->session
->ext
.alpn_selected
!= NULL
)
1124 s
->ext
.early_data_ok
= 0;
1126 if (!s
->server
|| !SSL_CONNECTION_IS_TLS13(s
))
1130 * Call alpn_select callback if needed. Has to be done after SNI and
1131 * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
1132 * we also have to do this before we decide whether to accept early_data.
1133 * In TLSv1.3 we've already negotiated our cipher so we do this call now.
1134 * For < TLSv1.3 we defer it until after cipher negotiation.
1136 * On failure SSLfatal() already called.
1138 return tls_handle_alpn(s
);
1141 static int init_sig_algs(SSL_CONNECTION
*s
, unsigned int context
)
1143 /* Clear any signature algorithms extension received */
1144 OPENSSL_free(s
->s3
.tmp
.peer_sigalgs
);
1145 s
->s3
.tmp
.peer_sigalgs
= NULL
;
1146 s
->s3
.tmp
.peer_sigalgslen
= 0;
1151 static int init_sig_algs_cert(SSL_CONNECTION
*s
,
1152 ossl_unused
unsigned int context
)
1154 /* Clear any signature algorithms extension received */
1155 OPENSSL_free(s
->s3
.tmp
.peer_cert_sigalgs
);
1156 s
->s3
.tmp
.peer_cert_sigalgs
= NULL
;
1157 s
->s3
.tmp
.peer_cert_sigalgslen
= 0;
1162 #ifndef OPENSSL_NO_SRP
1163 static int init_srp(SSL_CONNECTION
*s
, unsigned int context
)
1165 OPENSSL_free(s
->srp_ctx
.login
);
1166 s
->srp_ctx
.login
= NULL
;
1172 static int init_ec_point_formats(SSL_CONNECTION
*s
, unsigned int context
)
1174 OPENSSL_free(s
->ext
.peer_ecpointformats
);
1175 s
->ext
.peer_ecpointformats
= NULL
;
1176 s
->ext
.peer_ecpointformats_len
= 0;
1181 static int init_etm(SSL_CONNECTION
*s
, unsigned int context
)
1188 static int init_ems(SSL_CONNECTION
*s
, unsigned int context
)
1190 if (s
->s3
.flags
& TLS1_FLAGS_RECEIVED_EXTMS
) {
1191 s
->s3
.flags
&= ~TLS1_FLAGS_RECEIVED_EXTMS
;
1192 s
->s3
.flags
|= TLS1_FLAGS_REQUIRED_EXTMS
;
1198 static int final_ems(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
1201 * Check extended master secret extension is not dropped on
1204 if (!(s
->s3
.flags
& TLS1_FLAGS_RECEIVED_EXTMS
)
1205 && (s
->s3
.flags
& TLS1_FLAGS_REQUIRED_EXTMS
)) {
1206 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_R_INCONSISTENT_EXTMS
);
1209 if (!s
->server
&& s
->hit
) {
1211 * Check extended master secret extension is consistent with
1214 if (!(s
->s3
.flags
& TLS1_FLAGS_RECEIVED_EXTMS
) !=
1215 !(s
->session
->flags
& SSL_SESS_FLAG_EXTMS
)) {
1216 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_R_INCONSISTENT_EXTMS
);
1224 static int init_certificate_authorities(SSL_CONNECTION
*s
, unsigned int context
)
1226 sk_X509_NAME_pop_free(s
->s3
.tmp
.peer_ca_names
, X509_NAME_free
);
1227 s
->s3
.tmp
.peer_ca_names
= NULL
;
1231 static EXT_RETURN
tls_construct_certificate_authorities(SSL_CONNECTION
*s
,
1233 unsigned int context
,
1237 const STACK_OF(X509_NAME
) *ca_sk
= get_ca_names(s
);
1239 if (ca_sk
== NULL
|| sk_X509_NAME_num(ca_sk
) == 0)
1240 return EXT_RETURN_NOT_SENT
;
1242 if (!WPACKET_put_bytes_u16(pkt
, TLSEXT_TYPE_certificate_authorities
)
1243 || !WPACKET_start_sub_packet_u16(pkt
)) {
1244 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1245 return EXT_RETURN_FAIL
;
1248 if (!construct_ca_names(s
, ca_sk
, pkt
)) {
1249 /* SSLfatal() already called */
1250 return EXT_RETURN_FAIL
;
1253 if (!WPACKET_close(pkt
)) {
1254 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1255 return EXT_RETURN_FAIL
;
1258 return EXT_RETURN_SENT
;
1261 static int tls_parse_certificate_authorities(SSL_CONNECTION
*s
, PACKET
*pkt
,
1262 unsigned int context
, X509
*x
,
1265 if (!parse_ca_names(s
, pkt
))
1267 if (PACKET_remaining(pkt
) != 0) {
1268 SSLfatal(s
, SSL_AD_DECODE_ERROR
, SSL_R_BAD_EXTENSION
);
1274 #ifndef OPENSSL_NO_SRTP
1275 static int init_srtp(SSL_CONNECTION
*s
, unsigned int context
)
1278 s
->srtp_profile
= NULL
;
1284 static int final_sig_algs(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
1286 if (!sent
&& SSL_CONNECTION_IS_TLS13(s
) && !s
->hit
) {
1287 SSLfatal(s
, TLS13_AD_MISSING_EXTENSION
,
1288 SSL_R_MISSING_SIGALGS_EXTENSION
);
1295 static int final_key_share(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
1297 #if !defined(OPENSSL_NO_TLS1_3)
1298 if (!SSL_CONNECTION_IS_TLS13(s
))
1301 /* Nothing to do for key_share in an HRR */
1302 if ((context
& SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
) != 0)
1309 * we have no key_share
1311 * (we are not resuming
1312 * OR the kex_mode doesn't allow non key_share resumes)
1319 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE
) == 0)) {
1320 /* Nothing left we can do - just fail */
1321 SSLfatal(s
, SSL_AD_MISSING_EXTENSION
, SSL_R_NO_SUITABLE_KEY_SHARE
);
1329 * we have a suitable key_share
1332 * we are stateless AND we have no cookie
1334 * send a HelloRetryRequest
1337 * we didn't already send a HelloRetryRequest
1339 * the client sent a key_share extension
1341 * (we are not resuming
1342 * OR the kex_mode allows key_share resumes)
1344 * a shared group exists
1346 * send a HelloRetryRequest
1348 * we are not resuming
1350 * the kex_mode doesn't allow non key_share resumes
1354 * we are stateless AND we have no cookie
1356 * send a HelloRetryRequest
1359 if (s
->s3
.peer_tmp
!= NULL
) {
1360 /* We have a suitable key_share */
1361 if ((s
->s3
.flags
& TLS1_FLAGS_STATELESS
) != 0
1362 && !s
->ext
.cookieok
) {
1363 if (!ossl_assert(s
->hello_retry_request
== SSL_HRR_NONE
)) {
1365 * If we are stateless then we wouldn't know about any
1366 * previously sent HRR - so how can this be anything other
1369 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1372 s
->hello_retry_request
= SSL_HRR_PENDING
;
1376 /* No suitable key_share */
1377 if (s
->hello_retry_request
== SSL_HRR_NONE
&& sent
1379 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE_DHE
)
1381 const uint16_t *pgroups
, *clntgroups
;
1382 size_t num_groups
, clnt_num_groups
, i
;
1383 unsigned int group_id
= 0;
1385 /* Check if a shared group exists */
1387 /* Get the clients list of supported groups. */
1388 tls1_get_peer_groups(s
, &clntgroups
, &clnt_num_groups
);
1389 tls1_get_supported_groups(s
, &pgroups
, &num_groups
);
1392 * Find the first group we allow that is also in client's list
1394 for (i
= 0; i
< num_groups
; i
++) {
1395 group_id
= pgroups
[i
];
1397 if (check_in_list(s
, group_id
, clntgroups
, clnt_num_groups
,
1402 if (i
< num_groups
) {
1403 /* A shared group exists so send a HelloRetryRequest */
1404 s
->s3
.group_id
= group_id
;
1405 s
->hello_retry_request
= SSL_HRR_PENDING
;
1410 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE
) == 0) {
1411 /* Nothing left we can do - just fail */
1412 SSLfatal(s
, sent
? SSL_AD_HANDSHAKE_FAILURE
1413 : SSL_AD_MISSING_EXTENSION
,
1414 SSL_R_NO_SUITABLE_KEY_SHARE
);
1418 if ((s
->s3
.flags
& TLS1_FLAGS_STATELESS
) != 0
1419 && !s
->ext
.cookieok
) {
1420 if (!ossl_assert(s
->hello_retry_request
== SSL_HRR_NONE
)) {
1422 * If we are stateless then we wouldn't know about any
1423 * previously sent HRR - so how can this be anything other
1426 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1429 s
->hello_retry_request
= SSL_HRR_PENDING
;
1435 * We have a key_share so don't send any more HelloRetryRequest
1438 if (s
->hello_retry_request
== SSL_HRR_PENDING
)
1439 s
->hello_retry_request
= SSL_HRR_COMPLETE
;
1442 * For a client side resumption with no key_share we need to generate
1443 * the handshake secret (otherwise this is done during key_share
1446 if (!sent
&& !tls13_generate_handshake_secret(s
, NULL
, 0)) {
1447 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1451 #endif /* !defined(OPENSSL_NO_TLS1_3) */
1455 static int init_psk_kex_modes(SSL_CONNECTION
*s
, unsigned int context
)
1457 s
->ext
.psk_kex_mode
= TLSEXT_KEX_MODE_FLAG_NONE
;
1461 int tls_psk_do_binder(SSL_CONNECTION
*s
, const EVP_MD
*md
,
1462 const unsigned char *msgstart
,
1463 size_t binderoffset
, const unsigned char *binderin
,
1464 unsigned char *binderout
, SSL_SESSION
*sess
, int sign
,
1467 EVP_PKEY
*mackey
= NULL
;
1468 EVP_MD_CTX
*mctx
= NULL
;
1469 unsigned char hash
[EVP_MAX_MD_SIZE
], binderkey
[EVP_MAX_MD_SIZE
];
1470 unsigned char finishedkey
[EVP_MAX_MD_SIZE
], tmpbinder
[EVP_MAX_MD_SIZE
];
1471 unsigned char *early_secret
;
1472 #ifdef CHARSET_EBCDIC
1473 static const unsigned char resumption_label
[] = { 0x72, 0x65, 0x73, 0x20, 0x62, 0x69, 0x6E, 0x64, 0x65, 0x72, 0x00 };
1474 static const unsigned char external_label
[] = { 0x65, 0x78, 0x74, 0x20, 0x62, 0x69, 0x6E, 0x64, 0x65, 0x72, 0x00 };
1476 static const unsigned char resumption_label
[] = "res binder";
1477 static const unsigned char external_label
[] = "ext binder";
1479 const unsigned char *label
;
1480 size_t bindersize
, labelsize
, hashsize
;
1481 int hashsizei
= EVP_MD_get_size(md
);
1483 int usepskfored
= 0;
1484 SSL_CTX
*sctx
= SSL_CONNECTION_GET_CTX(s
);
1486 /* Ensure cast to size_t is safe */
1487 if (!ossl_assert(hashsizei
>= 0)) {
1488 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1491 hashsize
= (size_t)hashsizei
;
1494 && s
->early_data_state
== SSL_EARLY_DATA_CONNECTING
1495 && s
->session
->ext
.max_early_data
== 0
1496 && sess
->ext
.max_early_data
> 0)
1500 label
= external_label
;
1501 labelsize
= sizeof(external_label
) - 1;
1503 label
= resumption_label
;
1504 labelsize
= sizeof(resumption_label
) - 1;
1508 * Generate the early_secret. On the server side we've selected a PSK to
1509 * resume with (internal or external) so we always do this. On the client
1510 * side we do this for a non-external (i.e. resumption) PSK or external PSK
1511 * that will be used for early_data so that it is in place for sending early
1512 * data. For client side external PSK not being used for early_data we
1513 * generate it but store it away for later use.
1515 if (s
->server
|| !external
|| usepskfored
)
1516 early_secret
= (unsigned char *)s
->early_secret
;
1518 early_secret
= (unsigned char *)sess
->early_secret
;
1520 if (!tls13_generate_secret(s
, md
, NULL
, sess
->master_key
,
1521 sess
->master_key_length
, early_secret
)) {
1522 /* SSLfatal() already called */
1527 * Create the handshake hash for the binder key...the messages so far are
1530 mctx
= EVP_MD_CTX_new();
1532 || EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0
1533 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
1534 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1538 /* Generate the binder key */
1539 if (!tls13_hkdf_expand(s
, md
, early_secret
, label
, labelsize
, hash
,
1540 hashsize
, binderkey
, hashsize
, 1)) {
1541 /* SSLfatal() already called */
1545 /* Generate the finished key */
1546 if (!tls13_derive_finishedkey(s
, md
, binderkey
, finishedkey
, hashsize
)) {
1547 /* SSLfatal() already called */
1551 if (EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0) {
1552 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1557 * Get a hash of the ClientHello up to the start of the binders. If we are
1558 * following a HelloRetryRequest then this includes the hash of the first
1559 * ClientHello and the HelloRetryRequest itself.
1561 if (s
->hello_retry_request
== SSL_HRR_PENDING
) {
1566 hdatalen
= hdatalen_l
=
1567 BIO_get_mem_data(s
->s3
.handshake_buffer
, &hdata
);
1568 if (hdatalen_l
<= 0) {
1569 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_R_BAD_HANDSHAKE_LENGTH
);
1574 * For servers the handshake buffer data will include the second
1575 * ClientHello - which we don't want - so we need to take that bit off.
1578 PACKET hashprefix
, msg
;
1580 /* Find how many bytes are left after the first two messages */
1581 if (!PACKET_buf_init(&hashprefix
, hdata
, hdatalen
)
1582 || !PACKET_forward(&hashprefix
, 1)
1583 || !PACKET_get_length_prefixed_3(&hashprefix
, &msg
)
1584 || !PACKET_forward(&hashprefix
, 1)
1585 || !PACKET_get_length_prefixed_3(&hashprefix
, &msg
)) {
1586 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1589 hdatalen
-= PACKET_remaining(&hashprefix
);
1592 if (EVP_DigestUpdate(mctx
, hdata
, hdatalen
) <= 0) {
1593 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1598 if (EVP_DigestUpdate(mctx
, msgstart
, binderoffset
) <= 0
1599 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
1600 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1604 mackey
= EVP_PKEY_new_raw_private_key_ex(sctx
->libctx
, "HMAC",
1605 sctx
->propq
, finishedkey
,
1607 if (mackey
== NULL
) {
1608 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1613 binderout
= tmpbinder
;
1615 bindersize
= hashsize
;
1616 if (EVP_DigestSignInit_ex(mctx
, NULL
, EVP_MD_get0_name(md
), sctx
->libctx
,
1617 sctx
->propq
, mackey
, NULL
) <= 0
1618 || EVP_DigestSignUpdate(mctx
, hash
, hashsize
) <= 0
1619 || EVP_DigestSignFinal(mctx
, binderout
, &bindersize
) <= 0
1620 || bindersize
!= hashsize
) {
1621 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, ERR_R_INTERNAL_ERROR
);
1628 /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */
1629 ret
= (CRYPTO_memcmp(binderin
, binderout
, hashsize
) == 0);
1631 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_R_BINDER_DOES_NOT_VERIFY
);
1635 OPENSSL_cleanse(binderkey
, sizeof(binderkey
));
1636 OPENSSL_cleanse(finishedkey
, sizeof(finishedkey
));
1637 EVP_PKEY_free(mackey
);
1638 EVP_MD_CTX_free(mctx
);
1643 static int final_early_data(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
1649 if (context
== SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
1651 && !s
->ext
.early_data_ok
) {
1653 * If we get here then the server accepted our early_data but we
1654 * later realised that it shouldn't have done (e.g. inconsistent
1657 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_R_BAD_EARLY_DATA
);
1664 if (s
->max_early_data
== 0
1666 || s
->early_data_state
!= SSL_EARLY_DATA_ACCEPTING
1667 || !s
->ext
.early_data_ok
1668 || s
->hello_retry_request
!= SSL_HRR_NONE
1669 || (s
->allow_early_data_cb
!= NULL
1670 && !s
->allow_early_data_cb(SSL_CONNECTION_GET_SSL(s
),
1671 s
->allow_early_data_cb_data
))) {
1672 s
->ext
.early_data
= SSL_EARLY_DATA_REJECTED
;
1674 s
->ext
.early_data
= SSL_EARLY_DATA_ACCEPTED
;
1676 if (!tls13_change_cipher_state(s
,
1677 SSL3_CC_EARLY
| SSL3_CHANGE_CIPHER_SERVER_READ
)) {
1678 /* SSLfatal() already called */
1686 static int final_maxfragmentlen(SSL_CONNECTION
*s
, unsigned int context
,
1690 * Session resumption on server-side with MFL extension active
1691 * BUT MFL extension packet was not resent (i.e. sent == 0)
1693 if (s
->server
&& s
->hit
&& USE_MAX_FRAGMENT_LENGTH_EXT(s
->session
)
1695 SSLfatal(s
, SSL_AD_MISSING_EXTENSION
, SSL_R_BAD_EXTENSION
);
1699 /* Current SSL buffer is lower than requested MFL */
1700 if (s
->session
&& USE_MAX_FRAGMENT_LENGTH_EXT(s
->session
)
1701 && s
->max_send_fragment
< GET_MAX_FRAGMENT_LENGTH(s
->session
))
1702 /* trigger a larger buffer reallocation */
1703 if (!ssl3_setup_buffers(s
)) {
1704 /* SSLfatal() already called */
1711 static int init_post_handshake_auth(SSL_CONNECTION
*s
,
1712 ossl_unused
unsigned int context
)
1714 s
->post_handshake_auth
= SSL_PHA_NONE
;
1720 * If clients offer "pre_shared_key" without a "psk_key_exchange_modes"
1721 * extension, servers MUST abort the handshake.
1723 static int final_psk(SSL_CONNECTION
*s
, unsigned int context
, int sent
)
1725 if (s
->server
&& sent
&& s
->clienthello
!= NULL
1726 && !s
->clienthello
->pre_proc_exts
[TLSEXT_IDX_psk_kex_modes
].present
) {
1727 SSLfatal(s
, TLS13_AD_MISSING_EXTENSION
,
1728 SSL_R_MISSING_PSK_KEX_MODES_EXTENSION
);