2 * Copyright 2016-2018 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_locl.h"
14 #include "statem_locl.h"
15 #include "internal/cryptlib.h"
17 static int final_renegotiate(SSL
*s
, unsigned int context
, int sent
);
18 static int init_server_name(SSL
*s
, unsigned int context
);
19 static int final_server_name(SSL
*s
, unsigned int context
, int sent
);
21 static int final_ec_pt_formats(SSL
*s
, unsigned int context
, int sent
);
23 static int init_session_ticket(SSL
*s
, unsigned int context
);
24 #ifndef OPENSSL_NO_OCSP
25 static int init_status_request(SSL
*s
, unsigned int context
);
27 #ifndef OPENSSL_NO_NEXTPROTONEG
28 static int init_npn(SSL
*s
, unsigned int context
);
30 static int init_alpn(SSL
*s
, unsigned int context
);
31 static int final_alpn(SSL
*s
, unsigned int context
, int sent
);
32 static int init_sig_algs_cert(SSL
*s
, unsigned int context
);
33 static int init_sig_algs(SSL
*s
, unsigned int context
);
34 static int init_certificate_authorities(SSL
*s
, unsigned int context
);
35 static EXT_RETURN
tls_construct_certificate_authorities(SSL
*s
, WPACKET
*pkt
,
39 static int tls_parse_certificate_authorities(SSL
*s
, PACKET
*pkt
,
40 unsigned int context
, X509
*x
,
42 #ifndef OPENSSL_NO_SRP
43 static int init_srp(SSL
*s
, unsigned int context
);
45 static int init_etm(SSL
*s
, unsigned int context
);
46 static int init_ems(SSL
*s
, unsigned int context
);
47 static int final_ems(SSL
*s
, unsigned int context
, int sent
);
48 static int init_psk_kex_modes(SSL
*s
, unsigned int context
);
50 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_locl.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
,
167 * "supported_groups" is spread across several specifications.
168 * It was originally specified as "elliptic_curves" in RFC 4492,
169 * and broadened to include named FFDH groups by RFC 7919.
170 * Both RFCs 4492 and 7919 do not include a provision for the server
171 * to indicate to the client the complete list of groups supported
172 * by the server, with the server instead just indicating the
173 * selected group for this connection in the ServerKeyExchange
174 * message. TLS 1.3 adds a scheme for the server to indicate
175 * to the client its list of supported groups in the
176 * EncryptedExtensions message, but none of the relevant
177 * specifications permit sending supported_groups in the ServerHello.
178 * Nonetheless (possibly due to the close proximity to the
179 * "ec_point_formats" extension, which is allowed in the ServerHello),
180 * there are several servers that send this extension in the
181 * ServerHello anyway. Up to and including the 1.1.0 release,
182 * we did not check for the presence of nonpermitted extensions,
183 * so to avoid a regression, we must permit this extension in the
184 * TLS 1.2 ServerHello as well.
186 * Note that there is no tls_parse_stoc_supported_groups function,
187 * so we do not perform any additional parsing, validation, or
188 * processing on the server's group list -- this is just a minimal
189 * change to preserve compatibility with these misbehaving servers.
191 TLSEXT_TYPE_supported_groups
,
192 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
193 | SSL_EXT_TLS1_2_SERVER_HELLO
,
194 NULL
, tls_parse_ctos_supported_groups
, NULL
,
195 tls_construct_stoc_supported_groups
,
196 tls_construct_ctos_supported_groups
, NULL
203 TLSEXT_TYPE_session_ticket
,
204 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
205 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
206 init_session_ticket
, tls_parse_ctos_session_ticket
,
207 tls_parse_stoc_session_ticket
, tls_construct_stoc_session_ticket
,
208 tls_construct_ctos_session_ticket
, NULL
210 #ifndef OPENSSL_NO_OCSP
212 TLSEXT_TYPE_status_request
,
213 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
214 | SSL_EXT_TLS1_3_CERTIFICATE
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
215 init_status_request
, tls_parse_ctos_status_request
,
216 tls_parse_stoc_status_request
, tls_construct_stoc_status_request
,
217 tls_construct_ctos_status_request
, NULL
222 #ifndef OPENSSL_NO_NEXTPROTONEG
224 TLSEXT_TYPE_next_proto_neg
,
225 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
226 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
227 init_npn
, tls_parse_ctos_npn
, tls_parse_stoc_npn
,
228 tls_construct_stoc_next_proto_neg
, tls_construct_ctos_npn
, NULL
235 * Must appear in this list after server_name so that finalisation
236 * happens after server_name callbacks
238 TLSEXT_TYPE_application_layer_protocol_negotiation
,
239 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
240 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
,
241 init_alpn
, tls_parse_ctos_alpn
, tls_parse_stoc_alpn
,
242 tls_construct_stoc_alpn
, tls_construct_ctos_alpn
, final_alpn
244 #ifndef OPENSSL_NO_SRTP
246 TLSEXT_TYPE_use_srtp
,
247 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
248 | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
| SSL_EXT_DTLS_ONLY
,
249 init_srtp
, tls_parse_ctos_use_srtp
, tls_parse_stoc_use_srtp
,
250 tls_construct_stoc_use_srtp
, tls_construct_ctos_use_srtp
, NULL
256 TLSEXT_TYPE_encrypt_then_mac
,
257 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
258 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
259 init_etm
, tls_parse_ctos_etm
, tls_parse_stoc_etm
,
260 tls_construct_stoc_etm
, tls_construct_ctos_etm
, NULL
262 #ifndef OPENSSL_NO_CT
264 TLSEXT_TYPE_signed_certificate_timestamp
,
265 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
266 | SSL_EXT_TLS1_3_CERTIFICATE
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
269 * No server side support for this, but can be provided by a custom
270 * extension. This is an exception to the rule that custom extensions
271 * cannot override built in ones.
273 NULL
, tls_parse_stoc_sct
, NULL
, tls_construct_ctos_sct
, NULL
279 TLSEXT_TYPE_extended_master_secret
,
280 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
281 | SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
282 init_ems
, tls_parse_ctos_ems
, tls_parse_stoc_ems
,
283 tls_construct_stoc_ems
, tls_construct_ctos_ems
, final_ems
286 TLSEXT_TYPE_signature_algorithms_cert
,
287 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
288 init_sig_algs_cert
, tls_parse_ctos_sig_algs_cert
,
289 tls_parse_ctos_sig_algs_cert
,
290 /* We do not generate signature_algorithms_cert at present. */
294 TLSEXT_TYPE_post_handshake_auth
,
295 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ONLY
,
296 init_post_handshake_auth
,
297 tls_parse_ctos_post_handshake_auth
, NULL
,
298 NULL
, tls_construct_ctos_post_handshake_auth
,
302 TLSEXT_TYPE_signature_algorithms
,
303 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
,
304 init_sig_algs
, tls_parse_ctos_sig_algs
,
305 tls_parse_ctos_sig_algs
, tls_construct_ctos_sig_algs
,
306 tls_construct_ctos_sig_algs
, final_sig_algs
309 TLSEXT_TYPE_supported_versions
,
310 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
311 | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
,
313 /* Processed inline as part of version selection */
314 NULL
, tls_parse_stoc_supported_versions
,
315 tls_construct_stoc_supported_versions
,
316 tls_construct_ctos_supported_versions
, NULL
319 TLSEXT_TYPE_psk_kex_modes
,
320 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS_IMPLEMENTATION_ONLY
321 | SSL_EXT_TLS1_3_ONLY
,
322 init_psk_kex_modes
, tls_parse_ctos_psk_kex_modes
, NULL
, NULL
,
323 tls_construct_ctos_psk_kex_modes
, NULL
325 #ifndef OPENSSL_NO_EC
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
,
341 /* Must be after key_share */
343 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
344 | SSL_EXT_TLS_IMPLEMENTATION_ONLY
| SSL_EXT_TLS1_3_ONLY
,
345 NULL
, tls_parse_ctos_cookie
, tls_parse_stoc_cookie
,
346 tls_construct_stoc_cookie
, tls_construct_ctos_cookie
, NULL
350 * Special unsolicited ServerHello extension only used when
351 * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set
353 TLSEXT_TYPE_cryptopro_bug
,
354 SSL_EXT_TLS1_2_SERVER_HELLO
| SSL_EXT_TLS1_2_AND_BELOW_ONLY
,
355 NULL
, NULL
, NULL
, tls_construct_stoc_cryptopro_bug
, NULL
, NULL
358 TLSEXT_TYPE_early_data
,
359 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
360 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
| SSL_EXT_TLS1_3_ONLY
,
361 NULL
, tls_parse_ctos_early_data
, tls_parse_stoc_early_data
,
362 tls_construct_stoc_early_data
, tls_construct_ctos_early_data
,
366 TLSEXT_TYPE_certificate_authorities
,
367 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
368 | SSL_EXT_TLS1_3_ONLY
,
369 init_certificate_authorities
,
370 tls_parse_certificate_authorities
, tls_parse_certificate_authorities
,
371 tls_construct_certificate_authorities
,
372 tls_construct_certificate_authorities
, NULL
,
375 /* Must be immediately before pre_shared_key */
377 SSL_EXT_CLIENT_HELLO
,
379 /* We send this, but don't read it */
380 NULL
, NULL
, NULL
, tls_construct_ctos_padding
, NULL
383 /* Required by the TLSv1.3 spec to always be the last extension */
385 SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_3_SERVER_HELLO
386 | SSL_EXT_TLS_IMPLEMENTATION_ONLY
| SSL_EXT_TLS1_3_ONLY
,
387 NULL
, tls_parse_ctos_psk
, tls_parse_stoc_psk
, tls_construct_stoc_psk
,
388 tls_construct_ctos_psk
, NULL
392 /* Check whether an extension's context matches the current context */
393 static int validate_context(SSL
*s
, unsigned int extctx
, unsigned int thisctx
)
395 /* Check we're allowed to use this extension in this context */
396 if ((thisctx
& extctx
) == 0)
399 if (SSL_IS_DTLS(s
)) {
400 if ((extctx
& SSL_EXT_TLS_ONLY
) != 0)
402 } else if ((extctx
& SSL_EXT_DTLS_ONLY
) != 0) {
409 int tls_validate_all_contexts(SSL
*s
, unsigned int thisctx
, RAW_EXTENSION
*exts
)
411 size_t i
, num_exts
, builtin_num
= OSSL_NELEM(ext_defs
), offset
;
412 RAW_EXTENSION
*thisext
;
413 unsigned int context
;
414 ENDPOINT role
= ENDPOINT_BOTH
;
416 if ((thisctx
& SSL_EXT_CLIENT_HELLO
) != 0)
417 role
= ENDPOINT_SERVER
;
418 else if ((thisctx
& SSL_EXT_TLS1_2_SERVER_HELLO
) != 0)
419 role
= ENDPOINT_CLIENT
;
421 /* Calculate the number of extensions in the extensions list */
422 num_exts
= builtin_num
+ s
->cert
->custext
.meths_count
;
424 for (thisext
= exts
, i
= 0; i
< num_exts
; i
++, thisext
++) {
425 if (!thisext
->present
)
428 if (i
< builtin_num
) {
429 context
= ext_defs
[i
].context
;
431 custom_ext_method
*meth
= NULL
;
433 meth
= custom_ext_find(&s
->cert
->custext
, role
, thisext
->type
,
435 if (!ossl_assert(meth
!= NULL
))
437 context
= meth
->context
;
440 if (!validate_context(s
, context
, thisctx
))
448 * Verify whether we are allowed to use the extension |type| in the current
449 * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to
450 * indicate the extension is not allowed. If returning 1 then |*found| is set to
451 * the definition for the extension we found.
453 static int verify_extension(SSL
*s
, unsigned int context
, unsigned int type
,
454 custom_ext_methods
*meths
, RAW_EXTENSION
*rawexlist
,
455 RAW_EXTENSION
**found
)
458 size_t builtin_num
= OSSL_NELEM(ext_defs
);
459 const EXTENSION_DEFINITION
*thisext
;
461 for (i
= 0, thisext
= ext_defs
; i
< builtin_num
; i
++, thisext
++) {
462 if (type
== thisext
->type
) {
463 if (!validate_context(s
, thisext
->context
, context
))
466 *found
= &rawexlist
[i
];
471 /* Check the custom extensions */
474 ENDPOINT role
= ENDPOINT_BOTH
;
475 custom_ext_method
*meth
= NULL
;
477 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0)
478 role
= ENDPOINT_SERVER
;
479 else if ((context
& SSL_EXT_TLS1_2_SERVER_HELLO
) != 0)
480 role
= ENDPOINT_CLIENT
;
482 meth
= custom_ext_find(meths
, role
, type
, &offset
);
484 if (!validate_context(s
, meth
->context
, context
))
486 *found
= &rawexlist
[offset
+ builtin_num
];
491 /* Unknown extension. We allow it */
497 * Check whether the context defined for an extension |extctx| means whether
498 * the extension is relevant for the current context |thisctx| or not. Returns
499 * 1 if the extension is relevant for this context, and 0 otherwise
501 int extension_is_relevant(SSL
*s
, unsigned int extctx
, unsigned int thisctx
)
506 * For HRR we haven't selected the version yet but we know it will be
509 if ((thisctx
& SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
) != 0)
512 is_tls13
= SSL_IS_TLS13(s
);
515 && (extctx
& SSL_EXT_TLS_IMPLEMENTATION_ONLY
) != 0)
516 || (s
->version
== SSL3_VERSION
517 && (extctx
& SSL_EXT_SSL3_ALLOWED
) == 0)
519 * Note that SSL_IS_TLS13() means "TLS 1.3 has been negotiated",
520 * which is never true when generating the ClientHello.
521 * However, version negotiation *has* occurred by the time the
522 * ClientHello extensions are being parsed.
523 * Be careful to allow TLS 1.3-only extensions when generating
526 || (is_tls13
&& (extctx
& SSL_EXT_TLS1_2_AND_BELOW_ONLY
) != 0)
527 || (!is_tls13
&& (extctx
& SSL_EXT_TLS1_3_ONLY
) != 0
528 && (thisctx
& SSL_EXT_CLIENT_HELLO
) == 0)
529 || (s
->server
&& !is_tls13
&& (extctx
& SSL_EXT_TLS1_3_ONLY
) != 0)
530 || (s
->hit
&& (extctx
& SSL_EXT_IGNORE_ON_RESUMPTION
) != 0))
536 * Gather a list of all the extensions from the data in |packet]. |context|
537 * tells us which message this extension is for. The raw extension data is
538 * stored in |*res| on success. We don't actually process the content of the
539 * extensions yet, except to check their types. This function also runs the
540 * initialiser functions for all known extensions if |init| is nonzero (whether
541 * we have collected them or not). If successful the caller is responsible for
542 * freeing the contents of |*res|.
544 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
545 * more than one extension of the same type in a ClientHello or ServerHello.
546 * This function returns 1 if all extensions are unique and we have parsed their
547 * types, and 0 if the extensions contain duplicates, could not be successfully
548 * found, or an internal error occurred. We only check duplicates for
549 * extensions that we know about. We ignore others.
551 int tls_collect_extensions(SSL
*s
, PACKET
*packet
, unsigned int context
,
552 RAW_EXTENSION
**res
, size_t *len
, int init
)
554 PACKET extensions
= *packet
;
557 custom_ext_methods
*exts
= &s
->cert
->custext
;
558 RAW_EXTENSION
*raw_extensions
= NULL
;
559 const EXTENSION_DEFINITION
*thisexd
;
564 * Initialise server side custom extensions. Client side is done during
565 * construction of extensions for the ClientHello.
567 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0)
568 custom_ext_init(&s
->cert
->custext
);
570 num_exts
= OSSL_NELEM(ext_defs
) + (exts
!= NULL
? exts
->meths_count
: 0);
571 raw_extensions
= OPENSSL_zalloc(num_exts
* sizeof(*raw_extensions
));
572 if (raw_extensions
== NULL
) {
573 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_COLLECT_EXTENSIONS
,
574 ERR_R_MALLOC_FAILURE
);
579 while (PACKET_remaining(&extensions
) > 0) {
580 unsigned int type
, idx
;
582 RAW_EXTENSION
*thisex
;
584 if (!PACKET_get_net_2(&extensions
, &type
) ||
585 !PACKET_get_length_prefixed_2(&extensions
, &extension
)) {
586 SSLfatal(s
, SSL_AD_DECODE_ERROR
, SSL_F_TLS_COLLECT_EXTENSIONS
,
587 SSL_R_BAD_EXTENSION
);
591 * Verify this extension is allowed. We only check duplicates for
592 * extensions that we recognise. We also have a special case for the
593 * PSK extension, which must be the last one in the ClientHello.
595 if (!verify_extension(s
, context
, type
, exts
, raw_extensions
, &thisex
)
596 || (thisex
!= NULL
&& thisex
->present
== 1)
597 || (type
== TLSEXT_TYPE_psk
598 && (context
& SSL_EXT_CLIENT_HELLO
) != 0
599 && PACKET_remaining(&extensions
) != 0)) {
600 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_TLS_COLLECT_EXTENSIONS
,
601 SSL_R_BAD_EXTENSION
);
604 idx
= thisex
- raw_extensions
;
606 * Check that we requested this extension (if appropriate). Requests can
607 * be sent in the ClientHello and CertificateRequest. Unsolicited
608 * extensions can be sent in the NewSessionTicket. We only do this for
609 * the built-in extensions. Custom extensions have a different but
610 * similar check elsewhere.
612 * - The HRR cookie extension is unsolicited
613 * - The renegotiate extension is unsolicited (the client signals
614 * support via an SCSV)
615 * - The signed_certificate_timestamp extension can be provided by a
616 * custom extension or by the built-in version. We let the extension
617 * itself handle unsolicited response checks.
619 if (idx
< OSSL_NELEM(ext_defs
)
620 && (context
& (SSL_EXT_CLIENT_HELLO
621 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
622 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
)) == 0
623 && type
!= TLSEXT_TYPE_cookie
624 && type
!= TLSEXT_TYPE_renegotiate
625 && type
!= TLSEXT_TYPE_signed_certificate_timestamp
626 && (s
->ext
.extflags
[idx
] & SSL_EXT_FLAG_SENT
) == 0) {
627 SSLfatal(s
, SSL_AD_UNSUPPORTED_EXTENSION
,
628 SSL_F_TLS_COLLECT_EXTENSIONS
, SSL_R_UNSOLICITED_EXTENSION
);
631 if (thisex
!= NULL
) {
632 thisex
->data
= extension
;
635 thisex
->received_order
= i
++;
637 s
->ext
.debug_cb(s
, !s
->server
, thisex
->type
,
638 PACKET_data(&thisex
->data
),
639 PACKET_remaining(&thisex
->data
),
646 * Initialise all known extensions relevant to this context,
647 * whether we have found them or not
649 for (thisexd
= ext_defs
, i
= 0; i
< OSSL_NELEM(ext_defs
);
651 if (thisexd
->init
!= NULL
&& (thisexd
->context
& context
) != 0
652 && extension_is_relevant(s
, thisexd
->context
, context
)
653 && !thisexd
->init(s
, context
)) {
654 /* SSLfatal() already called */
660 *res
= raw_extensions
;
666 OPENSSL_free(raw_extensions
);
671 * Runs the parser for a given extension with index |idx|. |exts| contains the
672 * list of all parsed extensions previously collected by
673 * tls_collect_extensions(). The parser is only run if it is applicable for the
674 * given |context| and the parser has not already been run. If this is for a
675 * Certificate message, then we also provide the parser with the relevant
676 * Certificate |x| and its position in the |chainidx| with 0 being the first
677 * Certificate. Returns 1 on success or 0 on failure. If an extension is not
678 * present this counted as success.
680 int tls_parse_extension(SSL
*s
, TLSEXT_INDEX idx
, int context
,
681 RAW_EXTENSION
*exts
, X509
*x
, size_t chainidx
)
683 RAW_EXTENSION
*currext
= &exts
[idx
];
684 int (*parser
)(SSL
*s
, PACKET
*pkt
, unsigned int context
, X509
*x
,
685 size_t chainidx
) = NULL
;
687 /* Skip if the extension is not present */
688 if (!currext
->present
)
691 /* Skip if we've already parsed this extension */
697 if (idx
< OSSL_NELEM(ext_defs
)) {
698 /* We are handling a built-in extension */
699 const EXTENSION_DEFINITION
*extdef
= &ext_defs
[idx
];
701 /* Check if extension is defined for our protocol. If not, skip */
702 if (!extension_is_relevant(s
, extdef
->context
, context
))
705 parser
= s
->server
? extdef
->parse_ctos
: extdef
->parse_stoc
;
708 return parser(s
, &currext
->data
, context
, x
, chainidx
);
711 * If the parser is NULL we fall through to the custom extension
716 /* Parse custom extensions */
717 return custom_ext_parse(s
, context
, currext
->type
,
718 PACKET_data(&currext
->data
),
719 PACKET_remaining(&currext
->data
),
724 * Parse all remaining extensions that have not yet been parsed. Also calls the
725 * finalisation for all extensions at the end if |fin| is nonzero, whether we
726 * collected them or not. Returns 1 for success or 0 for failure. If we are
727 * working on a Certificate message then we also pass the Certificate |x| and
728 * its position in the |chainidx|, with 0 being the first certificate.
730 int tls_parse_all_extensions(SSL
*s
, int context
, RAW_EXTENSION
*exts
, X509
*x
,
731 size_t chainidx
, int fin
)
733 size_t i
, numexts
= OSSL_NELEM(ext_defs
);
734 const EXTENSION_DEFINITION
*thisexd
;
736 /* Calculate the number of extensions in the extensions list */
737 numexts
+= s
->cert
->custext
.meths_count
;
739 /* Parse each extension in turn */
740 for (i
= 0; i
< numexts
; i
++) {
741 if (!tls_parse_extension(s
, i
, context
, exts
, x
, chainidx
)) {
742 /* SSLfatal() already called */
749 * Finalise all known extensions relevant to this context,
750 * whether we have found them or not
752 for (i
= 0, thisexd
= ext_defs
; i
< OSSL_NELEM(ext_defs
);
754 if (thisexd
->final
!= NULL
&& (thisexd
->context
& context
) != 0
755 && !thisexd
->final(s
, context
, exts
[i
].present
)) {
756 /* SSLfatal() already called */
765 int should_add_extension(SSL
*s
, unsigned int extctx
, unsigned int thisctx
,
768 /* Skip if not relevant for our context */
769 if ((extctx
& thisctx
) == 0)
772 /* Check if this extension is defined for our protocol. If not, skip */
773 if (!extension_is_relevant(s
, extctx
, thisctx
)
774 || ((extctx
& SSL_EXT_TLS1_3_ONLY
) != 0
775 && (thisctx
& SSL_EXT_CLIENT_HELLO
) != 0
776 && (SSL_IS_DTLS(s
) || max_version
< TLS1_3_VERSION
)))
783 * Construct all the extensions relevant to the current |context| and write
784 * them to |pkt|. If this is an extension for a Certificate in a Certificate
785 * message, then |x| will be set to the Certificate we are handling, and
786 * |chainidx| will indicate the position in the chainidx we are processing (with
787 * 0 being the first in the chain). Returns 1 on success or 0 on failure. On a
788 * failure construction stops at the first extension to fail to construct.
790 int tls_construct_extensions(SSL
*s
, WPACKET
*pkt
, unsigned int context
,
791 X509
*x
, size_t chainidx
)
794 int min_version
, max_version
= 0, reason
;
795 const EXTENSION_DEFINITION
*thisexd
;
797 if (!WPACKET_start_sub_packet_u16(pkt
)
799 * If extensions are of zero length then we don't even add the
800 * extensions length bytes to a ClientHello/ServerHello
804 (SSL_EXT_CLIENT_HELLO
| SSL_EXT_TLS1_2_SERVER_HELLO
)) != 0
805 && !WPACKET_set_flags(pkt
,
806 WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH
))) {
807 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_CONSTRUCT_EXTENSIONS
,
808 ERR_R_INTERNAL_ERROR
);
812 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0) {
813 reason
= ssl_get_min_max_version(s
, &min_version
, &max_version
, NULL
);
815 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_CONSTRUCT_EXTENSIONS
,
821 /* Add custom extensions first */
822 if ((context
& SSL_EXT_CLIENT_HELLO
) != 0) {
823 /* On the server side with initialise during ClientHello parsing */
824 custom_ext_init(&s
->cert
->custext
);
826 if (!custom_ext_add(s
, context
, pkt
, x
, chainidx
, max_version
)) {
827 /* SSLfatal() already called */
831 for (i
= 0, thisexd
= ext_defs
; i
< OSSL_NELEM(ext_defs
); i
++, thisexd
++) {
832 EXT_RETURN (*construct
)(SSL
*s
, WPACKET
*pkt
, unsigned int context
,
833 X509
*x
, size_t chainidx
);
836 /* Skip if not relevant for our context */
837 if (!should_add_extension(s
, thisexd
->context
, context
, max_version
))
840 construct
= s
->server
? thisexd
->construct_stoc
841 : thisexd
->construct_ctos
;
843 if (construct
== NULL
)
846 ret
= construct(s
, pkt
, context
, x
, chainidx
);
847 if (ret
== EXT_RETURN_FAIL
) {
848 /* SSLfatal() already called */
851 if (ret
== EXT_RETURN_SENT
852 && (context
& (SSL_EXT_CLIENT_HELLO
853 | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
854 | SSL_EXT_TLS1_3_NEW_SESSION_TICKET
)) != 0)
855 s
->ext
.extflags
[i
] |= SSL_EXT_FLAG_SENT
;
858 if (!WPACKET_close(pkt
)) {
859 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_CONSTRUCT_EXTENSIONS
,
860 ERR_R_INTERNAL_ERROR
);
868 * Built in extension finalisation and initialisation functions. All initialise
869 * or finalise the associated extension type for the given |context|. For
870 * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
871 * otherwise. These functions return 1 on success or 0 on failure.
874 static int final_renegotiate(SSL
*s
, unsigned int context
, int sent
)
878 * Check if we can connect to a server that doesn't support safe
881 if (!(s
->options
& SSL_OP_LEGACY_SERVER_CONNECT
)
882 && !(s
->options
& SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
)
884 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_RENEGOTIATE
,
885 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED
);
892 /* Need RI if renegotiating */
894 && !(s
->options
& SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
)
896 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_RENEGOTIATE
,
897 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED
);
905 static int init_server_name(SSL
*s
, unsigned int context
)
908 s
->servername_done
= 0;
910 OPENSSL_free(s
->ext
.hostname
);
911 s
->ext
.hostname
= NULL
;
917 static int final_server_name(SSL
*s
, unsigned int context
, int sent
)
919 int ret
= SSL_TLSEXT_ERR_NOACK
;
920 int altmp
= SSL_AD_UNRECOGNIZED_NAME
;
921 int was_ticket
= (SSL_get_options(s
) & SSL_OP_NO_TICKET
) == 0;
923 if (!ossl_assert(s
->ctx
!= NULL
) || !ossl_assert(s
->session_ctx
!= NULL
)) {
924 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
925 ERR_R_INTERNAL_ERROR
);
929 if (s
->ctx
->ext
.servername_cb
!= NULL
)
930 ret
= s
->ctx
->ext
.servername_cb(s
, &altmp
,
931 s
->ctx
->ext
.servername_arg
);
932 else if (s
->session_ctx
->ext
.servername_cb
!= NULL
)
933 ret
= s
->session_ctx
->ext
.servername_cb(s
, &altmp
,
934 s
->session_ctx
->ext
.servername_arg
);
937 * For servers, propagate the SNI hostname from the temporary
938 * storage in the SSL to the persistent SSL_SESSION, now that we
939 * know we accepted it.
940 * Clients make this copy when parsing the server's response to
941 * the extension, which is when they find out that the negotiation
945 /* TODO(OpenSSL1.2) revisit !sent case */
946 if (sent
&& ret
== SSL_TLSEXT_ERR_OK
&& (!s
->hit
|| SSL_IS_TLS13(s
))) {
947 /* Only store the hostname in the session if we accepted it. */
948 OPENSSL_free(s
->session
->ext
.hostname
);
949 s
->session
->ext
.hostname
= OPENSSL_strdup(s
->ext
.hostname
);
950 if (s
->session
->ext
.hostname
== NULL
&& s
->ext
.hostname
!= NULL
) {
951 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
952 ERR_R_INTERNAL_ERROR
);
958 * If we switched contexts (whether here or in the client_hello callback),
959 * move the sess_accept increment from the session_ctx to the new
960 * context, to avoid the confusing situation of having sess_accept_good
961 * exceed sess_accept (zero) for the new context.
963 if (SSL_IS_FIRST_HANDSHAKE(s
) && s
->ctx
!= s
->session_ctx
) {
964 tsan_counter(&s
->ctx
->stats
.sess_accept
);
965 tsan_decr(&s
->session_ctx
->stats
.sess_accept
);
969 * If we're expecting to send a ticket, and tickets were previously enabled,
970 * and now tickets are disabled, then turn off expected ticket.
971 * Also, if this is not a resumption, create a new session ID
973 if (ret
== SSL_TLSEXT_ERR_OK
&& s
->ext
.ticket_expected
974 && was_ticket
&& (SSL_get_options(s
) & SSL_OP_NO_TICKET
) != 0) {
975 s
->ext
.ticket_expected
= 0;
977 SSL_SESSION
* ss
= SSL_get_session(s
);
980 OPENSSL_free(ss
->ext
.tick
);
983 ss
->ext
.tick_lifetime_hint
= 0;
984 ss
->ext
.tick_age_add
= 0;
985 ss
->ext
.tick_identity
= 0;
986 if (!ssl_generate_session_id(s
, ss
)) {
987 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
988 ERR_R_INTERNAL_ERROR
);
992 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_SERVER_NAME
,
993 ERR_R_INTERNAL_ERROR
);
1000 case SSL_TLSEXT_ERR_ALERT_FATAL
:
1001 SSLfatal(s
, altmp
, SSL_F_FINAL_SERVER_NAME
, SSL_R_CALLBACK_FAILED
);
1004 case SSL_TLSEXT_ERR_ALERT_WARNING
:
1005 /* TLSv1.3 doesn't have warning alerts so we suppress this */
1006 if (!SSL_IS_TLS13(s
))
1007 ssl3_send_alert(s
, SSL3_AL_WARNING
, altmp
);
1010 case SSL_TLSEXT_ERR_NOACK
:
1011 s
->servername_done
= 0;
1019 #ifndef OPENSSL_NO_EC
1020 static int final_ec_pt_formats(SSL
*s
, unsigned int context
, int sent
)
1022 unsigned long alg_k
, alg_a
;
1027 alg_k
= s
->s3
->tmp
.new_cipher
->algorithm_mkey
;
1028 alg_a
= s
->s3
->tmp
.new_cipher
->algorithm_auth
;
1031 * If we are client and using an elliptic curve cryptography cipher
1032 * suite, then if server returns an EC point formats lists extension it
1033 * must contain uncompressed.
1035 if (s
->ext
.ecpointformats
!= NULL
1036 && s
->ext
.ecpointformats_len
> 0
1037 && s
->session
->ext
.ecpointformats
!= NULL
1038 && s
->session
->ext
.ecpointformats_len
> 0
1039 && ((alg_k
& SSL_kECDHE
) || (alg_a
& SSL_aECDSA
))) {
1040 /* we are using an ECC cipher */
1042 unsigned char *list
= s
->session
->ext
.ecpointformats
;
1044 for (i
= 0; i
< s
->session
->ext
.ecpointformats_len
; i
++) {
1045 if (*list
++ == TLSEXT_ECPOINTFORMAT_uncompressed
)
1048 if (i
== s
->session
->ext
.ecpointformats_len
) {
1049 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_FINAL_EC_PT_FORMATS
,
1050 SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST
);
1059 static int init_session_ticket(SSL
*s
, unsigned int context
)
1062 s
->ext
.ticket_expected
= 0;
1067 #ifndef OPENSSL_NO_OCSP
1068 static int init_status_request(SSL
*s
, unsigned int context
)
1071 s
->ext
.status_type
= TLSEXT_STATUSTYPE_nothing
;
1074 * Ensure we get sensible values passed to tlsext_status_cb in the event
1075 * that we don't receive a status message
1077 OPENSSL_free(s
->ext
.ocsp
.resp
);
1078 s
->ext
.ocsp
.resp
= NULL
;
1079 s
->ext
.ocsp
.resp_len
= 0;
1086 #ifndef OPENSSL_NO_NEXTPROTONEG
1087 static int init_npn(SSL
*s
, unsigned int context
)
1089 s
->s3
->npn_seen
= 0;
1095 static int init_alpn(SSL
*s
, unsigned int context
)
1097 OPENSSL_free(s
->s3
->alpn_selected
);
1098 s
->s3
->alpn_selected
= NULL
;
1099 s
->s3
->alpn_selected_len
= 0;
1101 OPENSSL_free(s
->s3
->alpn_proposed
);
1102 s
->s3
->alpn_proposed
= NULL
;
1103 s
->s3
->alpn_proposed_len
= 0;
1108 static int final_alpn(SSL
*s
, unsigned int context
, int sent
)
1110 if (!s
->server
&& !sent
&& s
->session
->ext
.alpn_selected
!= NULL
)
1111 s
->ext
.early_data_ok
= 0;
1113 if (!s
->server
|| !SSL_IS_TLS13(s
))
1117 * Call alpn_select callback if needed. Has to be done after SNI and
1118 * cipher negotiation (HTTP/2 restricts permitted ciphers). In TLSv1.3
1119 * we also have to do this before we decide whether to accept early_data.
1120 * In TLSv1.3 we've already negotiated our cipher so we do this call now.
1121 * For < TLSv1.3 we defer it until after cipher negotiation.
1123 * On failure SSLfatal() already called.
1125 return tls_handle_alpn(s
);
1128 static int init_sig_algs(SSL
*s
, unsigned int context
)
1130 /* Clear any signature algorithms extension received */
1131 OPENSSL_free(s
->s3
->tmp
.peer_sigalgs
);
1132 s
->s3
->tmp
.peer_sigalgs
= NULL
;
1137 static int init_sig_algs_cert(SSL
*s
, unsigned int context
)
1139 /* Clear any signature algorithms extension received */
1140 OPENSSL_free(s
->s3
->tmp
.peer_cert_sigalgs
);
1141 s
->s3
->tmp
.peer_cert_sigalgs
= NULL
;
1146 #ifndef OPENSSL_NO_SRP
1147 static int init_srp(SSL
*s
, unsigned int context
)
1149 OPENSSL_free(s
->srp_ctx
.login
);
1150 s
->srp_ctx
.login
= NULL
;
1156 static int init_etm(SSL
*s
, unsigned int context
)
1163 static int init_ems(SSL
*s
, unsigned int context
)
1166 s
->s3
->flags
&= ~TLS1_FLAGS_RECEIVED_EXTMS
;
1171 static int final_ems(SSL
*s
, unsigned int context
, int sent
)
1173 if (!s
->server
&& s
->hit
) {
1175 * Check extended master secret extension is consistent with
1178 if (!(s
->s3
->flags
& TLS1_FLAGS_RECEIVED_EXTMS
) !=
1179 !(s
->session
->flags
& SSL_SESS_FLAG_EXTMS
)) {
1180 SSLfatal(s
, SSL_AD_HANDSHAKE_FAILURE
, SSL_F_FINAL_EMS
,
1181 SSL_R_INCONSISTENT_EXTMS
);
1189 static int init_certificate_authorities(SSL
*s
, unsigned int context
)
1191 sk_X509_NAME_pop_free(s
->s3
->tmp
.peer_ca_names
, X509_NAME_free
);
1192 s
->s3
->tmp
.peer_ca_names
= NULL
;
1196 static EXT_RETURN
tls_construct_certificate_authorities(SSL
*s
, WPACKET
*pkt
,
1197 unsigned int context
,
1201 const STACK_OF(X509_NAME
) *ca_sk
= get_ca_names(s
);
1203 if (ca_sk
== NULL
|| sk_X509_NAME_num(ca_sk
) == 0)
1204 return EXT_RETURN_NOT_SENT
;
1206 if (!WPACKET_put_bytes_u16(pkt
, TLSEXT_TYPE_certificate_authorities
)
1207 || !WPACKET_start_sub_packet_u16(pkt
)) {
1208 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
1209 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES
,
1210 ERR_R_INTERNAL_ERROR
);
1211 return EXT_RETURN_FAIL
;
1214 if (!construct_ca_names(s
, ca_sk
, pkt
)) {
1215 /* SSLfatal() already called */
1216 return EXT_RETURN_FAIL
;
1219 if (!WPACKET_close(pkt
)) {
1220 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
1221 SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES
,
1222 ERR_R_INTERNAL_ERROR
);
1223 return EXT_RETURN_FAIL
;
1226 return EXT_RETURN_SENT
;
1229 static int tls_parse_certificate_authorities(SSL
*s
, PACKET
*pkt
,
1230 unsigned int context
, X509
*x
,
1233 if (!parse_ca_names(s
, pkt
))
1235 if (PACKET_remaining(pkt
) != 0) {
1236 SSLfatal(s
, SSL_AD_DECODE_ERROR
,
1237 SSL_F_TLS_PARSE_CERTIFICATE_AUTHORITIES
, SSL_R_BAD_EXTENSION
);
1243 #ifndef OPENSSL_NO_SRTP
1244 static int init_srtp(SSL
*s
, unsigned int context
)
1247 s
->srtp_profile
= NULL
;
1253 static int final_sig_algs(SSL
*s
, unsigned int context
, int sent
)
1255 if (!sent
&& SSL_IS_TLS13(s
) && !s
->hit
) {
1256 SSLfatal(s
, TLS13_AD_MISSING_EXTENSION
, SSL_F_FINAL_SIG_ALGS
,
1257 SSL_R_MISSING_SIGALGS_EXTENSION
);
1264 #ifndef OPENSSL_NO_EC
1265 static int final_key_share(SSL
*s
, unsigned int context
, int sent
)
1267 if (!SSL_IS_TLS13(s
))
1270 /* Nothing to do for key_share in an HRR */
1271 if ((context
& SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
) != 0)
1278 * we have no key_share
1280 * (we are not resuming
1281 * OR the kex_mode doesn't allow non key_share resumes)
1288 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE
) == 0)) {
1289 /* Nothing left we can do - just fail */
1290 SSLfatal(s
, SSL_AD_MISSING_EXTENSION
, SSL_F_FINAL_KEY_SHARE
,
1291 SSL_R_NO_SUITABLE_KEY_SHARE
);
1299 * we have a suitable key_share
1302 * we are stateless AND we have no cookie
1304 * send a HelloRetryRequest
1307 * we didn't already send a HelloRetryRequest
1309 * the client sent a key_share extension
1311 * (we are not resuming
1312 * OR the kex_mode allows key_share resumes)
1314 * a shared group exists
1316 * send a HelloRetryRequest
1318 * we are not resuming
1320 * the kex_mode doesn't allow non key_share resumes
1324 * we are stateless AND we have no cookie
1326 * send a HelloRetryRequest
1329 if (s
->s3
->peer_tmp
!= NULL
) {
1330 /* We have a suitable key_share */
1331 if ((s
->s3
->flags
& TLS1_FLAGS_STATELESS
) != 0
1332 && !s
->ext
.cookieok
) {
1333 if (!ossl_assert(s
->hello_retry_request
== SSL_HRR_NONE
)) {
1335 * If we are stateless then we wouldn't know about any
1336 * previously sent HRR - so how can this be anything other
1339 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_KEY_SHARE
,
1340 ERR_R_INTERNAL_ERROR
);
1343 s
->hello_retry_request
= SSL_HRR_PENDING
;
1347 /* No suitable key_share */
1348 if (s
->hello_retry_request
== SSL_HRR_NONE
&& sent
1350 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE_DHE
)
1352 const uint16_t *pgroups
, *clntgroups
;
1353 size_t num_groups
, clnt_num_groups
, i
;
1354 unsigned int group_id
= 0;
1356 /* Check if a shared group exists */
1358 /* Get the clients list of supported groups. */
1359 tls1_get_peer_groups(s
, &clntgroups
, &clnt_num_groups
);
1360 tls1_get_supported_groups(s
, &pgroups
, &num_groups
);
1363 * Find the first group we allow that is also in client's list
1365 for (i
= 0; i
< num_groups
; i
++) {
1366 group_id
= pgroups
[i
];
1368 if (check_in_list(s
, group_id
, clntgroups
, clnt_num_groups
,
1373 if (i
< num_groups
) {
1374 /* A shared group exists so send a HelloRetryRequest */
1375 s
->s3
->group_id
= group_id
;
1376 s
->hello_retry_request
= SSL_HRR_PENDING
;
1381 || (s
->ext
.psk_kex_mode
& TLSEXT_KEX_MODE_FLAG_KE
) == 0) {
1382 /* Nothing left we can do - just fail */
1383 SSLfatal(s
, sent
? SSL_AD_HANDSHAKE_FAILURE
1384 : SSL_AD_MISSING_EXTENSION
,
1385 SSL_F_FINAL_KEY_SHARE
, SSL_R_NO_SUITABLE_KEY_SHARE
);
1389 if ((s
->s3
->flags
& TLS1_FLAGS_STATELESS
) != 0
1390 && !s
->ext
.cookieok
) {
1391 if (!ossl_assert(s
->hello_retry_request
== SSL_HRR_NONE
)) {
1393 * If we are stateless then we wouldn't know about any
1394 * previously sent HRR - so how can this be anything other
1397 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_KEY_SHARE
,
1398 ERR_R_INTERNAL_ERROR
);
1401 s
->hello_retry_request
= SSL_HRR_PENDING
;
1407 * We have a key_share so don't send any more HelloRetryRequest
1410 if (s
->hello_retry_request
== SSL_HRR_PENDING
)
1411 s
->hello_retry_request
= SSL_HRR_COMPLETE
;
1414 * For a client side resumption with no key_share we need to generate
1415 * the handshake secret (otherwise this is done during key_share
1418 if (!sent
&& !tls13_generate_handshake_secret(s
, NULL
, 0)) {
1419 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_FINAL_KEY_SHARE
,
1420 ERR_R_INTERNAL_ERROR
);
1429 static int init_psk_kex_modes(SSL
*s
, unsigned int context
)
1431 s
->ext
.psk_kex_mode
= TLSEXT_KEX_MODE_FLAG_NONE
;
1435 int tls_psk_do_binder(SSL
*s
, const EVP_MD
*md
, const unsigned char *msgstart
,
1436 size_t binderoffset
, const unsigned char *binderin
,
1437 unsigned char *binderout
, SSL_SESSION
*sess
, int sign
,
1440 EVP_PKEY
*mackey
= NULL
;
1441 EVP_MD_CTX
*mctx
= NULL
;
1442 unsigned char hash
[EVP_MAX_MD_SIZE
], binderkey
[EVP_MAX_MD_SIZE
];
1443 unsigned char finishedkey
[EVP_MAX_MD_SIZE
], tmpbinder
[EVP_MAX_MD_SIZE
];
1444 unsigned char *early_secret
;
1445 static const unsigned char resumption_label
[] = "res binder";
1446 static const unsigned char external_label
[] = "ext binder";
1447 const unsigned char *label
;
1448 size_t bindersize
, labelsize
, hashsize
;
1449 int hashsizei
= EVP_MD_size(md
);
1451 int usepskfored
= 0;
1453 /* Ensure cast to size_t is safe */
1454 if (!ossl_assert(hashsizei
>= 0)) {
1455 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1456 ERR_R_INTERNAL_ERROR
);
1459 hashsize
= (size_t)hashsizei
;
1462 && s
->early_data_state
== SSL_EARLY_DATA_CONNECTING
1463 && s
->session
->ext
.max_early_data
== 0
1464 && sess
->ext
.max_early_data
> 0)
1468 label
= external_label
;
1469 labelsize
= sizeof(external_label
) - 1;
1471 label
= resumption_label
;
1472 labelsize
= sizeof(resumption_label
) - 1;
1476 * Generate the early_secret. On the server side we've selected a PSK to
1477 * resume with (internal or external) so we always do this. On the client
1478 * side we do this for a non-external (i.e. resumption) PSK or external PSK
1479 * that will be used for early_data so that it is in place for sending early
1480 * data. For client side external PSK not being used for early_data we
1481 * generate it but store it away for later use.
1483 if (s
->server
|| !external
|| usepskfored
)
1484 early_secret
= (unsigned char *)s
->early_secret
;
1486 early_secret
= (unsigned char *)sess
->early_secret
;
1488 if (!tls13_generate_secret(s
, md
, NULL
, sess
->master_key
,
1489 sess
->master_key_length
, early_secret
)) {
1490 /* SSLfatal() already called */
1495 * Create the handshake hash for the binder key...the messages so far are
1498 mctx
= EVP_MD_CTX_new();
1500 || EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0
1501 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
1502 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1503 ERR_R_INTERNAL_ERROR
);
1507 /* Generate the binder key */
1508 if (!tls13_hkdf_expand(s
, md
, early_secret
, label
, labelsize
, hash
,
1509 hashsize
, binderkey
, hashsize
, 1)) {
1510 /* SSLfatal() already called */
1514 /* Generate the finished key */
1515 if (!tls13_derive_finishedkey(s
, md
, binderkey
, finishedkey
, hashsize
)) {
1516 /* SSLfatal() already called */
1520 if (EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0) {
1521 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1522 ERR_R_INTERNAL_ERROR
);
1527 * Get a hash of the ClientHello up to the start of the binders. If we are
1528 * following a HelloRetryRequest then this includes the hash of the first
1529 * ClientHello and the HelloRetryRequest itself.
1531 if (s
->hello_retry_request
== SSL_HRR_PENDING
) {
1536 hdatalen
= hdatalen_l
=
1537 BIO_get_mem_data(s
->s3
->handshake_buffer
, &hdata
);
1538 if (hdatalen_l
<= 0) {
1539 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1540 SSL_R_BAD_HANDSHAKE_LENGTH
);
1545 * For servers the handshake buffer data will include the second
1546 * ClientHello - which we don't want - so we need to take that bit off.
1549 PACKET hashprefix
, msg
;
1551 /* Find how many bytes are left after the first two messages */
1552 if (!PACKET_buf_init(&hashprefix
, hdata
, hdatalen
)
1553 || !PACKET_forward(&hashprefix
, 1)
1554 || !PACKET_get_length_prefixed_3(&hashprefix
, &msg
)
1555 || !PACKET_forward(&hashprefix
, 1)
1556 || !PACKET_get_length_prefixed_3(&hashprefix
, &msg
)) {
1557 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1558 ERR_R_INTERNAL_ERROR
);
1561 hdatalen
-= PACKET_remaining(&hashprefix
);
1564 if (EVP_DigestUpdate(mctx
, hdata
, hdatalen
) <= 0) {
1565 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1566 ERR_R_INTERNAL_ERROR
);
1571 if (EVP_DigestUpdate(mctx
, msgstart
, binderoffset
) <= 0
1572 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
1573 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1574 ERR_R_INTERNAL_ERROR
);
1578 mackey
= EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC
, NULL
, finishedkey
,
1580 if (mackey
== NULL
) {
1581 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1582 ERR_R_INTERNAL_ERROR
);
1587 binderout
= tmpbinder
;
1589 bindersize
= hashsize
;
1590 if (EVP_DigestSignInit(mctx
, NULL
, md
, NULL
, mackey
) <= 0
1591 || EVP_DigestSignUpdate(mctx
, hash
, hashsize
) <= 0
1592 || EVP_DigestSignFinal(mctx
, binderout
, &bindersize
) <= 0
1593 || bindersize
!= hashsize
) {
1594 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS_PSK_DO_BINDER
,
1595 ERR_R_INTERNAL_ERROR
);
1602 /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */
1603 ret
= (CRYPTO_memcmp(binderin
, binderout
, hashsize
) == 0);
1605 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_TLS_PSK_DO_BINDER
,
1606 SSL_R_BINDER_DOES_NOT_VERIFY
);
1610 OPENSSL_cleanse(binderkey
, sizeof(binderkey
));
1611 OPENSSL_cleanse(finishedkey
, sizeof(finishedkey
));
1612 EVP_PKEY_free(mackey
);
1613 EVP_MD_CTX_free(mctx
);
1618 static int final_early_data(SSL
*s
, unsigned int context
, int sent
)
1624 if (context
== SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
1626 && !s
->ext
.early_data_ok
) {
1628 * If we get here then the server accepted our early_data but we
1629 * later realised that it shouldn't have done (e.g. inconsistent
1632 SSLfatal(s
, SSL_AD_ILLEGAL_PARAMETER
, SSL_F_FINAL_EARLY_DATA
,
1633 SSL_R_BAD_EARLY_DATA
);
1640 if (s
->max_early_data
== 0
1642 || s
->session
->ext
.tick_identity
!= 0
1643 || s
->early_data_state
!= SSL_EARLY_DATA_ACCEPTING
1644 || !s
->ext
.early_data_ok
1645 || s
->hello_retry_request
!= SSL_HRR_NONE
1646 || (s
->ctx
->allow_early_data_cb
!= NULL
1647 && !s
->ctx
->allow_early_data_cb(s
,
1648 s
->ctx
->allow_early_data_cb_data
))) {
1649 s
->ext
.early_data
= SSL_EARLY_DATA_REJECTED
;
1651 s
->ext
.early_data
= SSL_EARLY_DATA_ACCEPTED
;
1653 if (!tls13_change_cipher_state(s
,
1654 SSL3_CC_EARLY
| SSL3_CHANGE_CIPHER_SERVER_READ
)) {
1655 /* SSLfatal() already called */
1663 static int final_maxfragmentlen(SSL
*s
, unsigned int context
, int sent
)
1666 * Session resumption on server-side with MFL extension active
1667 * BUT MFL extension packet was not resent (i.e. sent == 0)
1669 if (s
->server
&& s
->hit
&& USE_MAX_FRAGMENT_LENGTH_EXT(s
->session
)
1671 SSLfatal(s
, SSL_AD_MISSING_EXTENSION
, SSL_F_FINAL_MAXFRAGMENTLEN
,
1672 SSL_R_BAD_EXTENSION
);
1676 /* Current SSL buffer is lower than requested MFL */
1677 if (s
->session
&& USE_MAX_FRAGMENT_LENGTH_EXT(s
->session
)
1678 && s
->max_send_fragment
< GET_MAX_FRAGMENT_LENGTH(s
->session
))
1679 /* trigger a larger buffer reallocation */
1680 if (!ssl3_setup_buffers(s
)) {
1681 /* SSLfatal() already called */
1688 static int init_post_handshake_auth(SSL
*s
, unsigned int context
)
1690 s
->post_handshake_auth
= SSL_PHA_NONE
;