1 /*
2 * Copyright 2016-2024 The OpenSSL Project Authors. All Rights Reserved.
3 *
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
8 */
9
10 #include <openssl/ocsp.h>
11 #include "../ssl_local.h"
12 #include "internal/cryptlib.h"
13 #include "statem_local.h"
14
tls_construct_ctos_renegotiate(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)15 EXT_RETURN tls_construct_ctos_renegotiate(SSL *s, WPACKET *pkt,
16 unsigned int context, X509 *x,
17 size_t chainidx)
18 {
19 /* Add RI if renegotiating */
20 if (!s->renegotiate)
21 return EXT_RETURN_NOT_SENT;
22
23 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate)
24 || !WPACKET_start_sub_packet_u16(pkt)
25 || !WPACKET_sub_memcpy_u8(pkt, s->s3.previous_client_finished,
26 s->s3.previous_client_finished_len)
27 || !WPACKET_close(pkt)) {
28 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
29 return EXT_RETURN_FAIL;
30 }
31
32 return EXT_RETURN_SENT;
33 }
34
tls_construct_ctos_server_name(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)35 EXT_RETURN tls_construct_ctos_server_name(SSL *s, WPACKET *pkt,
36 unsigned int context, X509 *x,
37 size_t chainidx)
38 {
39 if (s->ext.hostname == NULL)
40 return EXT_RETURN_NOT_SENT;
41
42 /* Add TLS extension servername to the Client Hello message */
43 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_name)
44 /* Sub-packet for server_name extension */
45 || !WPACKET_start_sub_packet_u16(pkt)
46 /* Sub-packet for servername list (always 1 hostname)*/
47 || !WPACKET_start_sub_packet_u16(pkt)
48 || !WPACKET_put_bytes_u8(pkt, TLSEXT_NAMETYPE_host_name)
49 || !WPACKET_sub_memcpy_u16(pkt, s->ext.hostname,
50 strlen(s->ext.hostname))
51 || !WPACKET_close(pkt)
52 || !WPACKET_close(pkt)) {
53 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
54 return EXT_RETURN_FAIL;
55 }
56
57 return EXT_RETURN_SENT;
58 }
59
60 /* Push a Max Fragment Len extension into ClientHello */
tls_construct_ctos_maxfragmentlen(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)61 EXT_RETURN tls_construct_ctos_maxfragmentlen(SSL *s, WPACKET *pkt,
62 unsigned int context, X509 *x,
63 size_t chainidx)
64 {
65 if (s->ext.max_fragment_len_mode == TLSEXT_max_fragment_length_DISABLED)
66 return EXT_RETURN_NOT_SENT;
67
68 /* Add Max Fragment Length extension if client enabled it. */
69 /*-
70 * 4 bytes for this extension type and extension length
71 * 1 byte for the Max Fragment Length code value.
72 */
73 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_max_fragment_length)
74 /* Sub-packet for Max Fragment Length extension (1 byte) */
75 || !WPACKET_start_sub_packet_u16(pkt)
76 || !WPACKET_put_bytes_u8(pkt, s->ext.max_fragment_len_mode)
77 || !WPACKET_close(pkt)) {
78 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
79 return EXT_RETURN_FAIL;
80 }
81
82 return EXT_RETURN_SENT;
83 }
84
85 #ifndef OPENSSL_NO_SRP
tls_construct_ctos_srp(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)86 EXT_RETURN tls_construct_ctos_srp(SSL *s, WPACKET *pkt, unsigned int context,
87 X509 *x, size_t chainidx)
88 {
89 /* Add SRP username if there is one */
90 if (s->srp_ctx.login == NULL)
91 return EXT_RETURN_NOT_SENT;
92
93 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_srp)
94 /* Sub-packet for SRP extension */
95 || !WPACKET_start_sub_packet_u16(pkt)
96 || !WPACKET_start_sub_packet_u8(pkt)
97 /* login must not be zero...internal error if so */
98 || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)
99 || !WPACKET_memcpy(pkt, s->srp_ctx.login,
100 strlen(s->srp_ctx.login))
101 || !WPACKET_close(pkt)
102 || !WPACKET_close(pkt)) {
103 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
104 return EXT_RETURN_FAIL;
105 }
106
107 return EXT_RETURN_SENT;
108 }
109 #endif
110
use_ecc(SSL * s,int min_version,int max_version)111 static int use_ecc(SSL *s, int min_version, int max_version)
112 {
113 int i, end, ret = 0;
114 unsigned long alg_k, alg_a;
115 STACK_OF(SSL_CIPHER) *cipher_stack = NULL;
116 const uint16_t *pgroups = NULL;
117 size_t num_groups, j;
118
119 /* See if we support any ECC ciphersuites */
120 if (s->version == SSL3_VERSION)
121 return 0;
122
123 cipher_stack = SSL_get1_supported_ciphers(s);
124 end = sk_SSL_CIPHER_num(cipher_stack);
125 for (i = 0; i < end; i++) {
126 const SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i);
127
128 alg_k = c->algorithm_mkey;
129 alg_a = c->algorithm_auth;
130 if ((alg_k & (SSL_kECDHE | SSL_kECDHEPSK))
131 || (alg_a & SSL_aECDSA)
132 || c->min_tls >= TLS1_3_VERSION) {
133 ret = 1;
134 break;
135 }
136 }
137 sk_SSL_CIPHER_free(cipher_stack);
138 if (!ret)
139 return 0;
140
141 /* Check we have at least one EC supported group */
142 tls1_get_supported_groups(s, &pgroups, &num_groups);
143 for (j = 0; j < num_groups; j++) {
144 uint16_t ctmp = pgroups[j];
145
146 if (tls_valid_group(s, ctmp, min_version, max_version, 1, NULL)
147 && tls_group_allowed(s, ctmp, SSL_SECOP_CURVE_SUPPORTED))
148 return 1;
149 }
150
151 return 0;
152 }
153
tls_construct_ctos_ec_pt_formats(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)154 EXT_RETURN tls_construct_ctos_ec_pt_formats(SSL *s, WPACKET *pkt,
155 unsigned int context, X509 *x,
156 size_t chainidx)
157 {
158 const unsigned char *pformats;
159 size_t num_formats;
160 int reason, min_version, max_version;
161
162 reason = ssl_get_min_max_version(s, &min_version, &max_version, NULL);
163 if (reason != 0) {
164 SSLfatal(s, SSL_AD_INTERNAL_ERROR, reason);
165 return EXT_RETURN_FAIL;
166 }
167 if (!use_ecc(s, min_version, max_version))
168 return EXT_RETURN_NOT_SENT;
169
170 /* Add TLS extension ECPointFormats to the ClientHello message */
171 tls1_get_formatlist(s, &pformats, &num_formats);
172
173 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_ec_point_formats)
174 /* Sub-packet for formats extension */
175 || !WPACKET_start_sub_packet_u16(pkt)
176 || !WPACKET_sub_memcpy_u8(pkt, pformats, num_formats)
177 || !WPACKET_close(pkt)) {
178 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
179 return EXT_RETURN_FAIL;
180 }
181
182 return EXT_RETURN_SENT;
183 }
184
tls_construct_ctos_supported_groups(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)185 EXT_RETURN tls_construct_ctos_supported_groups(SSL *s, WPACKET *pkt,
186 unsigned int context, X509 *x,
187 size_t chainidx)
188 {
189 const uint16_t *pgroups = NULL;
190 size_t num_groups = 0, i, tls13added = 0, added = 0;
191 int min_version, max_version, reason;
192
193 reason = ssl_get_min_max_version(s, &min_version, &max_version, NULL);
194 if (reason != 0) {
195 SSLfatal(s, SSL_AD_INTERNAL_ERROR, reason);
196 return EXT_RETURN_FAIL;
197 }
198
199 /*
200 * We only support EC groups in TLSv1.2 or below, and in DTLS. Therefore
201 * if we don't have EC support then we don't send this extension.
202 */
203 if (!use_ecc(s, min_version, max_version)
204 && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION))
205 return EXT_RETURN_NOT_SENT;
206
207 /*
208 * Add TLS extension supported_groups to the ClientHello message
209 */
210 tls1_get_supported_groups(s, &pgroups, &num_groups);
211
212 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_groups)
213 /* Sub-packet for supported_groups extension */
214 || !WPACKET_start_sub_packet_u16(pkt)
215 || !WPACKET_start_sub_packet_u16(pkt)
216 || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)) {
217 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
218 return EXT_RETURN_FAIL;
219 }
220 /* Copy group ID if supported */
221 for (i = 0; i < num_groups; i++) {
222 uint16_t ctmp = pgroups[i];
223 int okfortls13;
224
225 if (tls_valid_group(s, ctmp, min_version, max_version, 0, &okfortls13)
226 && tls_group_allowed(s, ctmp, SSL_SECOP_CURVE_SUPPORTED)) {
227 if (!WPACKET_put_bytes_u16(pkt, ctmp)) {
228 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
229 return EXT_RETURN_FAIL;
230 }
231 if (okfortls13 && max_version == TLS1_3_VERSION)
232 tls13added++;
233 added++;
234 }
235 }
236 if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
237 if (added == 0)
238 SSLfatal_data(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_GROUPS,
239 "No groups enabled for max supported SSL/TLS version");
240 else
241 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
242 return EXT_RETURN_FAIL;
243 }
244
245 if (tls13added == 0 && max_version == TLS1_3_VERSION) {
246 SSLfatal_data(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_GROUPS,
247 "No groups enabled for max supported SSL/TLS version");
248 return EXT_RETURN_FAIL;
249 }
250
251 return EXT_RETURN_SENT;
252 }
253
tls_construct_ctos_session_ticket(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)254 EXT_RETURN tls_construct_ctos_session_ticket(SSL *s, WPACKET *pkt,
255 unsigned int context, X509 *x,
256 size_t chainidx)
257 {
258 size_t ticklen;
259
260 if (!tls_use_ticket(s))
261 return EXT_RETURN_NOT_SENT;
262
263 if (!s->new_session && s->session != NULL
264 && s->session->ext.tick != NULL
265 && s->session->ssl_version != TLS1_3_VERSION) {
266 ticklen = s->session->ext.ticklen;
267 } else if (s->session && s->ext.session_ticket != NULL
268 && s->ext.session_ticket->data != NULL) {
269 ticklen = s->ext.session_ticket->length;
270 s->session->ext.tick = OPENSSL_malloc(ticklen);
271 if (s->session->ext.tick == NULL) {
272 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
273 return EXT_RETURN_FAIL;
274 }
275 memcpy(s->session->ext.tick,
276 s->ext.session_ticket->data, ticklen);
277 s->session->ext.ticklen = ticklen;
278 } else {
279 ticklen = 0;
280 }
281
282 if (ticklen == 0 && s->ext.session_ticket != NULL &&
283 s->ext.session_ticket->data == NULL)
284 return EXT_RETURN_NOT_SENT;
285
286 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_session_ticket)
287 || !WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick, ticklen)) {
288 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
289 return EXT_RETURN_FAIL;
290 }
291
292 return EXT_RETURN_SENT;
293 }
294
tls_construct_ctos_sig_algs(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)295 EXT_RETURN tls_construct_ctos_sig_algs(SSL *s, WPACKET *pkt,
296 unsigned int context, X509 *x,
297 size_t chainidx)
298 {
299 size_t salglen;
300 const uint16_t *salg;
301
302 if (!SSL_CLIENT_USE_SIGALGS(s))
303 return EXT_RETURN_NOT_SENT;
304
305 salglen = tls12_get_psigalgs(s, 1, &salg);
306 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signature_algorithms)
307 /* Sub-packet for sig-algs extension */
308 || !WPACKET_start_sub_packet_u16(pkt)
309 /* Sub-packet for the actual list */
310 || !WPACKET_start_sub_packet_u16(pkt)
311 || !tls12_copy_sigalgs(s, pkt, salg, salglen)
312 || !WPACKET_close(pkt)
313 || !WPACKET_close(pkt)) {
314 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
315 return EXT_RETURN_FAIL;
316 }
317
318 return EXT_RETURN_SENT;
319 }
320
321 #ifndef OPENSSL_NO_OCSP
tls_construct_ctos_status_request(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)322 EXT_RETURN tls_construct_ctos_status_request(SSL *s, WPACKET *pkt,
323 unsigned int context, X509 *x,
324 size_t chainidx)
325 {
326 int i;
327
328 /* This extension isn't defined for client Certificates */
329 if (x != NULL)
330 return EXT_RETURN_NOT_SENT;
331
332 if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp)
333 return EXT_RETURN_NOT_SENT;
334
335 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_status_request)
336 /* Sub-packet for status request extension */
337 || !WPACKET_start_sub_packet_u16(pkt)
338 || !WPACKET_put_bytes_u8(pkt, TLSEXT_STATUSTYPE_ocsp)
339 /* Sub-packet for the ids */
340 || !WPACKET_start_sub_packet_u16(pkt)) {
341 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
342 return EXT_RETURN_FAIL;
343 }
344 for (i = 0; i < sk_OCSP_RESPID_num(s->ext.ocsp.ids); i++) {
345 unsigned char *idbytes;
346 OCSP_RESPID *id = sk_OCSP_RESPID_value(s->ext.ocsp.ids, i);
347 int idlen = i2d_OCSP_RESPID(id, NULL);
348
349 if (idlen <= 0
350 /* Sub-packet for an individual id */
351 || !WPACKET_sub_allocate_bytes_u16(pkt, idlen, &idbytes)
352 || i2d_OCSP_RESPID(id, &idbytes) != idlen) {
353 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
354 return EXT_RETURN_FAIL;
355 }
356 }
357 if (!WPACKET_close(pkt)
358 || !WPACKET_start_sub_packet_u16(pkt)) {
359 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
360 return EXT_RETURN_FAIL;
361 }
362 if (s->ext.ocsp.exts) {
363 unsigned char *extbytes;
364 int extlen = i2d_X509_EXTENSIONS(s->ext.ocsp.exts, NULL);
365
366 if (extlen < 0) {
367 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
368 return EXT_RETURN_FAIL;
369 }
370 if (!WPACKET_allocate_bytes(pkt, extlen, &extbytes)
371 || i2d_X509_EXTENSIONS(s->ext.ocsp.exts, &extbytes)
372 != extlen) {
373 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
374 return EXT_RETURN_FAIL;
375 }
376 }
377 if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
378 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
379 return EXT_RETURN_FAIL;
380 }
381
382 return EXT_RETURN_SENT;
383 }
384 #endif
385
386 #ifndef OPENSSL_NO_NEXTPROTONEG
tls_construct_ctos_npn(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)387 EXT_RETURN tls_construct_ctos_npn(SSL *s, WPACKET *pkt, unsigned int context,
388 X509 *x, size_t chainidx)
389 {
390 if (s->ctx->ext.npn_select_cb == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
391 return EXT_RETURN_NOT_SENT;
392
393 /*
394 * The client advertises an empty extension to indicate its support
395 * for Next Protocol Negotiation
396 */
397 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_next_proto_neg)
398 || !WPACKET_put_bytes_u16(pkt, 0)) {
399 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
400 return EXT_RETURN_FAIL;
401 }
402
403 return EXT_RETURN_SENT;
404 }
405 #endif
406
tls_construct_ctos_alpn(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)407 EXT_RETURN tls_construct_ctos_alpn(SSL *s, WPACKET *pkt, unsigned int context,
408 X509 *x, size_t chainidx)
409 {
410 s->s3.alpn_sent = 0;
411
412 if (s->ext.alpn == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
413 return EXT_RETURN_NOT_SENT;
414
415 if (!WPACKET_put_bytes_u16(pkt,
416 TLSEXT_TYPE_application_layer_protocol_negotiation)
417 /* Sub-packet ALPN extension */
418 || !WPACKET_start_sub_packet_u16(pkt)
419 || !WPACKET_sub_memcpy_u16(pkt, s->ext.alpn, s->ext.alpn_len)
420 || !WPACKET_close(pkt)) {
421 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
422 return EXT_RETURN_FAIL;
423 }
424 s->s3.alpn_sent = 1;
425
426 return EXT_RETURN_SENT;
427 }
428
429
430 #ifndef OPENSSL_NO_SRTP
tls_construct_ctos_use_srtp(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)431 EXT_RETURN tls_construct_ctos_use_srtp(SSL *s, WPACKET *pkt,
432 unsigned int context, X509 *x,
433 size_t chainidx)
434 {
435 STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = SSL_get_srtp_profiles(s);
436 int i, end;
437
438 if (clnt == NULL)
439 return EXT_RETURN_NOT_SENT;
440
441 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_use_srtp)
442 /* Sub-packet for SRTP extension */
443 || !WPACKET_start_sub_packet_u16(pkt)
444 /* Sub-packet for the protection profile list */
445 || !WPACKET_start_sub_packet_u16(pkt)) {
446 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
447 return EXT_RETURN_FAIL;
448 }
449
450 end = sk_SRTP_PROTECTION_PROFILE_num(clnt);
451 for (i = 0; i < end; i++) {
452 const SRTP_PROTECTION_PROFILE *prof =
453 sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
454
455 if (prof == NULL || !WPACKET_put_bytes_u16(pkt, prof->id)) {
456 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
457 return EXT_RETURN_FAIL;
458 }
459 }
460 if (!WPACKET_close(pkt)
461 /* Add an empty use_mki value */
462 || !WPACKET_put_bytes_u8(pkt, 0)
463 || !WPACKET_close(pkt)) {
464 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
465 return EXT_RETURN_FAIL;
466 }
467
468 return EXT_RETURN_SENT;
469 }
470 #endif
471
tls_construct_ctos_etm(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)472 EXT_RETURN tls_construct_ctos_etm(SSL *s, WPACKET *pkt, unsigned int context,
473 X509 *x, size_t chainidx)
474 {
475 if (s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
476 return EXT_RETURN_NOT_SENT;
477
478 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_encrypt_then_mac)
479 || !WPACKET_put_bytes_u16(pkt, 0)) {
480 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
481 return EXT_RETURN_FAIL;
482 }
483
484 return EXT_RETURN_SENT;
485 }
486
487 #ifndef OPENSSL_NO_CT
tls_construct_ctos_sct(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)488 EXT_RETURN tls_construct_ctos_sct(SSL *s, WPACKET *pkt, unsigned int context,
489 X509 *x, size_t chainidx)
490 {
491 if (s->ct_validation_callback == NULL)
492 return EXT_RETURN_NOT_SENT;
493
494 /* Not defined for client Certificates */
495 if (x != NULL)
496 return EXT_RETURN_NOT_SENT;
497
498 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signed_certificate_timestamp)
499 || !WPACKET_put_bytes_u16(pkt, 0)) {
500 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
501 return EXT_RETURN_FAIL;
502 }
503
504 return EXT_RETURN_SENT;
505 }
506 #endif
507
tls_construct_ctos_ems(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)508 EXT_RETURN tls_construct_ctos_ems(SSL *s, WPACKET *pkt, unsigned int context,
509 X509 *x, size_t chainidx)
510 {
511 if (s->options & SSL_OP_NO_EXTENDED_MASTER_SECRET)
512 return EXT_RETURN_NOT_SENT;
513
514 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_extended_master_secret)
515 || !WPACKET_put_bytes_u16(pkt, 0)) {
516 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
517 return EXT_RETURN_FAIL;
518 }
519
520 return EXT_RETURN_SENT;
521 }
522
tls_construct_ctos_supported_versions(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)523 EXT_RETURN tls_construct_ctos_supported_versions(SSL *s, WPACKET *pkt,
524 unsigned int context, X509 *x,
525 size_t chainidx)
526 {
527 int currv, min_version, max_version, reason;
528
529 reason = ssl_get_min_max_version(s, &min_version, &max_version, NULL);
530 if (reason != 0) {
531 SSLfatal(s, SSL_AD_INTERNAL_ERROR, reason);
532 return EXT_RETURN_FAIL;
533 }
534
535 /*
536 * Don't include this if we can't negotiate TLSv1.3. We can do a straight
537 * comparison here because we will never be called in DTLS.
538 */
539 if (max_version < TLS1_3_VERSION)
540 return EXT_RETURN_NOT_SENT;
541
542 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_versions)
543 || !WPACKET_start_sub_packet_u16(pkt)
544 || !WPACKET_start_sub_packet_u8(pkt)) {
545 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
546 return EXT_RETURN_FAIL;
547 }
548
549 for (currv = max_version; currv >= min_version; currv--) {
550 if (!WPACKET_put_bytes_u16(pkt, currv)) {
551 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
552 return EXT_RETURN_FAIL;
553 }
554 }
555 if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
556 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
557 return EXT_RETURN_FAIL;
558 }
559
560 return EXT_RETURN_SENT;
561 }
562
563 /*
564 * Construct a psk_kex_modes extension.
565 */
tls_construct_ctos_psk_kex_modes(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)566 EXT_RETURN tls_construct_ctos_psk_kex_modes(SSL *s, WPACKET *pkt,
567 unsigned int context, X509 *x,
568 size_t chainidx)
569 {
570 #ifndef OPENSSL_NO_TLS1_3
571 int nodhe = s->options & SSL_OP_ALLOW_NO_DHE_KEX;
572
573 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk_kex_modes)
574 || !WPACKET_start_sub_packet_u16(pkt)
575 || !WPACKET_start_sub_packet_u8(pkt)
576 || !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE_DHE)
577 || (nodhe && !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE))
578 || !WPACKET_close(pkt)
579 || !WPACKET_close(pkt)) {
580 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
581 return EXT_RETURN_FAIL;
582 }
583
584 s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_KE_DHE;
585 if (nodhe)
586 s->ext.psk_kex_mode |= TLSEXT_KEX_MODE_FLAG_KE;
587 #endif
588
589 return EXT_RETURN_SENT;
590 }
591
592 #ifndef OPENSSL_NO_TLS1_3
add_key_share(SSL * s,WPACKET * pkt,unsigned int curve_id)593 static int add_key_share(SSL *s, WPACKET *pkt, unsigned int curve_id)
594 {
595 unsigned char *encoded_point = NULL;
596 EVP_PKEY *key_share_key = NULL;
597 size_t encodedlen;
598
599 if (s->s3.tmp.pkey != NULL) {
600 if (!ossl_assert(s->hello_retry_request == SSL_HRR_PENDING)) {
601 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
602 return 0;
603 }
604 /*
605 * Could happen if we got an HRR that wasn't requesting a new key_share
606 */
607 key_share_key = s->s3.tmp.pkey;
608 } else {
609 key_share_key = ssl_generate_pkey_group(s, curve_id);
610 if (key_share_key == NULL) {
611 /* SSLfatal() already called */
612 return 0;
613 }
614 }
615
616 /* Encode the public key. */
617 encodedlen = EVP_PKEY_get1_encoded_public_key(key_share_key,
618 &encoded_point);
619 if (encodedlen == 0) {
620 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
621 goto err;
622 }
623
624 /* Create KeyShareEntry */
625 if (!WPACKET_put_bytes_u16(pkt, curve_id)
626 || !WPACKET_sub_memcpy_u16(pkt, encoded_point, encodedlen)) {
627 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
628 goto err;
629 }
630
631 /*
632 * When changing to send more than one key_share we're
633 * going to need to be able to save more than one EVP_PKEY. For now
634 * we reuse the existing tmp.pkey
635 */
636 s->s3.tmp.pkey = key_share_key;
637 s->s3.group_id = curve_id;
638 OPENSSL_free(encoded_point);
639
640 return 1;
641 err:
642 if (s->s3.tmp.pkey == NULL)
643 EVP_PKEY_free(key_share_key);
644 OPENSSL_free(encoded_point);
645 return 0;
646 }
647 #endif
648
tls_construct_ctos_key_share(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)649 EXT_RETURN tls_construct_ctos_key_share(SSL *s, WPACKET *pkt,
650 unsigned int context, X509 *x,
651 size_t chainidx)
652 {
653 #ifndef OPENSSL_NO_TLS1_3
654 size_t i, num_groups = 0;
655 const uint16_t *pgroups = NULL;
656 uint16_t curve_id = 0;
657
658 /* key_share extension */
659 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_key_share)
660 /* Extension data sub-packet */
661 || !WPACKET_start_sub_packet_u16(pkt)
662 /* KeyShare list sub-packet */
663 || !WPACKET_start_sub_packet_u16(pkt)) {
664 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
665 return EXT_RETURN_FAIL;
666 }
667
668 tls1_get_supported_groups(s, &pgroups, &num_groups);
669
670 /*
671 * Make the number of key_shares sent configurable. For
672 * now, we just send one
673 */
674 if (s->s3.group_id != 0) {
675 curve_id = s->s3.group_id;
676 } else {
677 for (i = 0; i < num_groups; i++) {
678
679 if (!tls_group_allowed(s, pgroups[i], SSL_SECOP_CURVE_SUPPORTED))
680 continue;
681
682 if (!tls_valid_group(s, pgroups[i], TLS1_3_VERSION, TLS1_3_VERSION,
683 0, NULL))
684 continue;
685
686 curve_id = pgroups[i];
687 break;
688 }
689 }
690
691 if (curve_id == 0) {
692 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_KEY_SHARE);
693 return EXT_RETURN_FAIL;
694 }
695
696 if (!add_key_share(s, pkt, curve_id)) {
697 /* SSLfatal() already called */
698 return EXT_RETURN_FAIL;
699 }
700
701 if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
702 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
703 return EXT_RETURN_FAIL;
704 }
705 return EXT_RETURN_SENT;
706 #else
707 return EXT_RETURN_NOT_SENT;
708 #endif
709 }
710
tls_construct_ctos_cookie(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)711 EXT_RETURN tls_construct_ctos_cookie(SSL *s, WPACKET *pkt, unsigned int context,
712 X509 *x, size_t chainidx)
713 {
714 EXT_RETURN ret = EXT_RETURN_FAIL;
715
716 /* Should only be set if we've had an HRR */
717 if (s->ext.tls13_cookie_len == 0)
718 return EXT_RETURN_NOT_SENT;
719
720 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_cookie)
721 /* Extension data sub-packet */
722 || !WPACKET_start_sub_packet_u16(pkt)
723 || !WPACKET_sub_memcpy_u16(pkt, s->ext.tls13_cookie,
724 s->ext.tls13_cookie_len)
725 || !WPACKET_close(pkt)) {
726 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
727 goto end;
728 }
729
730 ret = EXT_RETURN_SENT;
731 end:
732 OPENSSL_free(s->ext.tls13_cookie);
733 s->ext.tls13_cookie = NULL;
734 s->ext.tls13_cookie_len = 0;
735
736 return ret;
737 }
738
tls_construct_ctos_early_data(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)739 EXT_RETURN tls_construct_ctos_early_data(SSL *s, WPACKET *pkt,
740 unsigned int context, X509 *x,
741 size_t chainidx)
742 {
743 #ifndef OPENSSL_NO_PSK
744 char identity[PSK_MAX_IDENTITY_LEN + 1];
745 #endif /* OPENSSL_NO_PSK */
746 const unsigned char *id = NULL;
747 size_t idlen = 0;
748 SSL_SESSION *psksess = NULL;
749 SSL_SESSION *edsess = NULL;
750 const EVP_MD *handmd = NULL;
751
752 if (s->hello_retry_request == SSL_HRR_PENDING)
753 handmd = ssl_handshake_md(s);
754
755 if (s->psk_use_session_cb != NULL
756 && (!s->psk_use_session_cb(s, handmd, &id, &idlen, &psksess)
757 || (psksess != NULL
758 && psksess->ssl_version != TLS1_3_VERSION))) {
759 SSL_SESSION_free(psksess);
760 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
761 return EXT_RETURN_FAIL;
762 }
763
764 #ifndef OPENSSL_NO_PSK
765 if (psksess == NULL && s->psk_client_callback != NULL) {
766 unsigned char psk[PSK_MAX_PSK_LEN];
767 size_t psklen = 0;
768
769 memset(identity, 0, sizeof(identity));
770 psklen = s->psk_client_callback(s, NULL, identity, sizeof(identity) - 1,
771 psk, sizeof(psk));
772
773 if (psklen > PSK_MAX_PSK_LEN) {
774 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, ERR_R_INTERNAL_ERROR);
775 return EXT_RETURN_FAIL;
776 } else if (psklen > 0) {
777 const unsigned char tls13_aes128gcmsha256_id[] = { 0x13, 0x01 };
778 const SSL_CIPHER *cipher;
779
780 idlen = strlen(identity);
781 if (idlen > PSK_MAX_IDENTITY_LEN) {
782 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
783 return EXT_RETURN_FAIL;
784 }
785 id = (unsigned char *)identity;
786
787 /*
788 * We found a PSK using an old style callback. We don't know
789 * the digest so we default to SHA256 as per the TLSv1.3 spec
790 */
791 cipher = SSL_CIPHER_find(s, tls13_aes128gcmsha256_id);
792 if (cipher == NULL) {
793 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
794 return EXT_RETURN_FAIL;
795 }
796
797 psksess = SSL_SESSION_new();
798 if (psksess == NULL
799 || !SSL_SESSION_set1_master_key(psksess, psk, psklen)
800 || !SSL_SESSION_set_cipher(psksess, cipher)
801 || !SSL_SESSION_set_protocol_version(psksess, TLS1_3_VERSION)) {
802 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
803 OPENSSL_cleanse(psk, psklen);
804 return EXT_RETURN_FAIL;
805 }
806 OPENSSL_cleanse(psk, psklen);
807 }
808 }
809 #endif /* OPENSSL_NO_PSK */
810
811 SSL_SESSION_free(s->psksession);
812 s->psksession = psksess;
813 if (psksess != NULL) {
814 OPENSSL_free(s->psksession_id);
815 s->psksession_id = OPENSSL_memdup(id, idlen);
816 if (s->psksession_id == NULL) {
817 s->psksession_id_len = 0;
818 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
819 return EXT_RETURN_FAIL;
820 }
821 s->psksession_id_len = idlen;
822 }
823
824 if (s->early_data_state != SSL_EARLY_DATA_CONNECTING
825 || (s->session->ext.max_early_data == 0
826 && (psksess == NULL || psksess->ext.max_early_data == 0))) {
827 s->max_early_data = 0;
828 return EXT_RETURN_NOT_SENT;
829 }
830 edsess = s->session->ext.max_early_data != 0 ? s->session : psksess;
831 s->max_early_data = edsess->ext.max_early_data;
832
833 if (edsess->ext.hostname != NULL) {
834 if (s->ext.hostname == NULL
835 || (s->ext.hostname != NULL
836 && strcmp(s->ext.hostname, edsess->ext.hostname) != 0)) {
837 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
838 SSL_R_INCONSISTENT_EARLY_DATA_SNI);
839 return EXT_RETURN_FAIL;
840 }
841 }
842
843 if ((s->ext.alpn == NULL && edsess->ext.alpn_selected != NULL)) {
844 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
845 return EXT_RETURN_FAIL;
846 }
847
848 /*
849 * Verify that we are offering an ALPN protocol consistent with the early
850 * data.
851 */
852 if (edsess->ext.alpn_selected != NULL) {
853 PACKET prots, alpnpkt;
854 int found = 0;
855
856 if (!PACKET_buf_init(&prots, s->ext.alpn, s->ext.alpn_len)) {
857 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
858 return EXT_RETURN_FAIL;
859 }
860 while (PACKET_get_length_prefixed_1(&prots, &alpnpkt)) {
861 if (PACKET_equal(&alpnpkt, edsess->ext.alpn_selected,
862 edsess->ext.alpn_selected_len)) {
863 found = 1;
864 break;
865 }
866 }
867 if (!found) {
868 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
869 SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
870 return EXT_RETURN_FAIL;
871 }
872 }
873
874 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_early_data)
875 || !WPACKET_start_sub_packet_u16(pkt)
876 || !WPACKET_close(pkt)) {
877 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
878 return EXT_RETURN_FAIL;
879 }
880
881 /*
882 * We set this to rejected here. Later, if the server acknowledges the
883 * extension, we set it to accepted.
884 */
885 s->ext.early_data = SSL_EARLY_DATA_REJECTED;
886 s->ext.early_data_ok = 1;
887
888 return EXT_RETURN_SENT;
889 }
890
891 #define F5_WORKAROUND_MIN_MSG_LEN 0xff
892 #define F5_WORKAROUND_MAX_MSG_LEN 0x200
893
894 /*
895 * PSK pre binder overhead =
896 * 2 bytes for TLSEXT_TYPE_psk
897 * 2 bytes for extension length
898 * 2 bytes for identities list length
899 * 2 bytes for identity length
900 * 4 bytes for obfuscated_ticket_age
901 * 2 bytes for binder list length
902 * 1 byte for binder length
903 * The above excludes the number of bytes for the identity itself and the
904 * subsequent binder bytes
905 */
906 #define PSK_PRE_BINDER_OVERHEAD (2 + 2 + 2 + 2 + 4 + 2 + 1)
907
tls_construct_ctos_padding(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)908 EXT_RETURN tls_construct_ctos_padding(SSL *s, WPACKET *pkt,
909 unsigned int context, X509 *x,
910 size_t chainidx)
911 {
912 unsigned char *padbytes;
913 size_t hlen;
914
915 if ((s->options & SSL_OP_TLSEXT_PADDING) == 0)
916 return EXT_RETURN_NOT_SENT;
917
918 /*
919 * Add padding to workaround bugs in F5 terminators. See RFC7685.
920 * This code calculates the length of all extensions added so far but
921 * excludes the PSK extension (because that MUST be written last). Therefore
922 * this extension MUST always appear second to last.
923 */
924 if (!WPACKET_get_total_written(pkt, &hlen)) {
925 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
926 return EXT_RETURN_FAIL;
927 }
928
929 /*
930 * If we're going to send a PSK then that will be written out after this
931 * extension, so we need to calculate how long it is going to be.
932 */
933 if (s->session->ssl_version == TLS1_3_VERSION
934 && s->session->ext.ticklen != 0
935 && s->session->cipher != NULL) {
936 const EVP_MD *md = ssl_md(s->ctx, s->session->cipher->algorithm2);
937
938 if (md != NULL) {
939 /*
940 * Add the fixed PSK overhead, the identity length and the binder
941 * length.
942 */
943 hlen += PSK_PRE_BINDER_OVERHEAD + s->session->ext.ticklen
944 + EVP_MD_get_size(md);
945 }
946 }
947
948 if (hlen > F5_WORKAROUND_MIN_MSG_LEN && hlen < F5_WORKAROUND_MAX_MSG_LEN) {
949 /* Calculate the amount of padding we need to add */
950 hlen = F5_WORKAROUND_MAX_MSG_LEN - hlen;
951
952 /*
953 * Take off the size of extension header itself (2 bytes for type and
954 * 2 bytes for length bytes), but ensure that the extension is at least
955 * 1 byte long so as not to have an empty extension last (WebSphere 7.x,
956 * 8.x are intolerant of that condition)
957 */
958 if (hlen > 4)
959 hlen -= 4;
960 else
961 hlen = 1;
962
963 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_padding)
964 || !WPACKET_sub_allocate_bytes_u16(pkt, hlen, &padbytes)) {
965 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
966 return EXT_RETURN_FAIL;
967 }
968 memset(padbytes, 0, hlen);
969 }
970
971 return EXT_RETURN_SENT;
972 }
973
974 /*
975 * Construct the pre_shared_key extension
976 */
tls_construct_ctos_psk(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)977 EXT_RETURN tls_construct_ctos_psk(SSL *s, WPACKET *pkt, unsigned int context,
978 X509 *x, size_t chainidx)
979 {
980 #ifndef OPENSSL_NO_TLS1_3
981 uint32_t agesec, agems = 0;
982 size_t reshashsize = 0, pskhashsize = 0, binderoffset, msglen;
983 unsigned char *resbinder = NULL, *pskbinder = NULL, *msgstart = NULL;
984 const EVP_MD *handmd = NULL, *mdres = NULL, *mdpsk = NULL;
985 int dores = 0;
986
987 s->ext.tick_identity = 0;
988
989 /*
990 * Note: At this stage of the code we only support adding a single
991 * resumption PSK. If we add support for multiple PSKs then the length
992 * calculations in the padding extension will need to be adjusted.
993 */
994
995 /*
996 * If this is an incompatible or new session then we have nothing to resume
997 * so don't add this extension.
998 */
999 if (s->session->ssl_version != TLS1_3_VERSION
1000 || (s->session->ext.ticklen == 0 && s->psksession == NULL))
1001 return EXT_RETURN_NOT_SENT;
1002
1003 if (s->hello_retry_request == SSL_HRR_PENDING)
1004 handmd = ssl_handshake_md(s);
1005
1006 if (s->session->ext.ticklen != 0) {
1007 /* Get the digest associated with the ciphersuite in the session */
1008 if (s->session->cipher == NULL) {
1009 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1010 return EXT_RETURN_FAIL;
1011 }
1012 mdres = ssl_md(s->ctx, s->session->cipher->algorithm2);
1013 if (mdres == NULL) {
1014 /*
1015 * Don't recognize this cipher so we can't use the session.
1016 * Ignore it
1017 */
1018 goto dopsksess;
1019 }
1020
1021 if (s->hello_retry_request == SSL_HRR_PENDING && mdres != handmd) {
1022 /*
1023 * Selected ciphersuite hash does not match the hash for the session
1024 * so we can't use it.
1025 */
1026 goto dopsksess;
1027 }
1028
1029 /*
1030 * Technically the C standard just says time() returns a time_t and says
1031 * nothing about the encoding of that type. In practice most
1032 * implementations follow POSIX which holds it as an integral type in
1033 * seconds since epoch. We've already made the assumption that we can do
1034 * this in multiple places in the code, so portability shouldn't be an
1035 * issue.
1036 */
1037 agesec = (uint32_t)(time(NULL) - s->session->time);
1038 /*
1039 * We calculate the age in seconds but the server may work in ms. Due to
1040 * rounding errors we could overestimate the age by up to 1s. It is
1041 * better to underestimate it. Otherwise, if the RTT is very short, when
1042 * the server calculates the age reported by the client it could be
1043 * bigger than the age calculated on the server - which should never
1044 * happen.
1045 */
1046 if (agesec > 0)
1047 agesec--;
1048
1049 if (s->session->ext.tick_lifetime_hint < agesec) {
1050 /* Ticket is too old. Ignore it. */
1051 goto dopsksess;
1052 }
1053
1054 /*
1055 * Calculate age in ms. We're just doing it to nearest second. Should be
1056 * good enough.
1057 */
1058 agems = agesec * (uint32_t)1000;
1059
1060 if (agesec != 0 && agems / (uint32_t)1000 != agesec) {
1061 /*
1062 * Overflow. Shouldn't happen unless this is a *really* old session.
1063 * If so we just ignore it.
1064 */
1065 goto dopsksess;
1066 }
1067
1068 /*
1069 * Obfuscate the age. Overflow here is fine, this addition is supposed
1070 * to be mod 2^32.
1071 */
1072 agems += s->session->ext.tick_age_add;
1073
1074 reshashsize = EVP_MD_get_size(mdres);
1075 s->ext.tick_identity++;
1076 dores = 1;
1077 }
1078
1079 dopsksess:
1080 if (!dores && s->psksession == NULL)
1081 return EXT_RETURN_NOT_SENT;
1082
1083 if (s->psksession != NULL) {
1084 mdpsk = ssl_md(s->ctx, s->psksession->cipher->algorithm2);
1085 if (mdpsk == NULL) {
1086 /*
1087 * Don't recognize this cipher so we can't use the session.
1088 * If this happens it's an application bug.
1089 */
1090 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1091 return EXT_RETURN_FAIL;
1092 }
1093
1094 if (s->hello_retry_request == SSL_HRR_PENDING && mdpsk != handmd) {
1095 /*
1096 * Selected ciphersuite hash does not match the hash for the PSK
1097 * session. This is an application bug.
1098 */
1099 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1100 return EXT_RETURN_FAIL;
1101 }
1102
1103 pskhashsize = EVP_MD_get_size(mdpsk);
1104 }
1105
1106 /* Create the extension, but skip over the binder for now */
1107 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk)
1108 || !WPACKET_start_sub_packet_u16(pkt)
1109 || !WPACKET_start_sub_packet_u16(pkt)) {
1110 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1111 return EXT_RETURN_FAIL;
1112 }
1113
1114 if (dores) {
1115 if (!WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick,
1116 s->session->ext.ticklen)
1117 || !WPACKET_put_bytes_u32(pkt, agems)) {
1118 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1119 return EXT_RETURN_FAIL;
1120 }
1121 }
1122
1123 if (s->psksession != NULL) {
1124 if (!WPACKET_sub_memcpy_u16(pkt, s->psksession_id,
1125 s->psksession_id_len)
1126 || !WPACKET_put_bytes_u32(pkt, 0)) {
1127 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1128 return EXT_RETURN_FAIL;
1129 }
1130 s->ext.tick_identity++;
1131 }
1132
1133 if (!WPACKET_close(pkt)
1134 || !WPACKET_get_total_written(pkt, &binderoffset)
1135 || !WPACKET_start_sub_packet_u16(pkt)
1136 || (dores
1137 && !WPACKET_sub_allocate_bytes_u8(pkt, reshashsize, &resbinder))
1138 || (s->psksession != NULL
1139 && !WPACKET_sub_allocate_bytes_u8(pkt, pskhashsize, &pskbinder))
1140 || !WPACKET_close(pkt)
1141 || !WPACKET_close(pkt)
1142 || !WPACKET_get_total_written(pkt, &msglen)
1143 /*
1144 * We need to fill in all the sub-packet lengths now so we can
1145 * calculate the HMAC of the message up to the binders
1146 */
1147 || !WPACKET_fill_lengths(pkt)) {
1148 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1149 return EXT_RETURN_FAIL;
1150 }
1151
1152 msgstart = WPACKET_get_curr(pkt) - msglen;
1153
1154 if (dores
1155 && tls_psk_do_binder(s, mdres, msgstart, binderoffset, NULL,
1156 resbinder, s->session, 1, 0) != 1) {
1157 /* SSLfatal() already called */
1158 return EXT_RETURN_FAIL;
1159 }
1160
1161 if (s->psksession != NULL
1162 && tls_psk_do_binder(s, mdpsk, msgstart, binderoffset, NULL,
1163 pskbinder, s->psksession, 1, 1) != 1) {
1164 /* SSLfatal() already called */
1165 return EXT_RETURN_FAIL;
1166 }
1167
1168 return EXT_RETURN_SENT;
1169 #else
1170 return EXT_RETURN_NOT_SENT;
1171 #endif
1172 }
1173
tls_construct_ctos_post_handshake_auth(SSL * s,WPACKET * pkt,ossl_unused unsigned int context,ossl_unused X509 * x,ossl_unused size_t chainidx)1174 EXT_RETURN tls_construct_ctos_post_handshake_auth(SSL *s, WPACKET *pkt,
1175 ossl_unused unsigned int context,
1176 ossl_unused X509 *x,
1177 ossl_unused size_t chainidx)
1178 {
1179 #ifndef OPENSSL_NO_TLS1_3
1180 if (!s->pha_enabled)
1181 return EXT_RETURN_NOT_SENT;
1182
1183 /* construct extension - 0 length, no contents */
1184 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_post_handshake_auth)
1185 || !WPACKET_start_sub_packet_u16(pkt)
1186 || !WPACKET_close(pkt)) {
1187 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1188 return EXT_RETURN_FAIL;
1189 }
1190
1191 s->post_handshake_auth = SSL_PHA_EXT_SENT;
1192
1193 return EXT_RETURN_SENT;
1194 #else
1195 return EXT_RETURN_NOT_SENT;
1196 #endif
1197 }
1198
1199
1200 /*
1201 * Parse the server's renegotiation binding and abort if it's not right
1202 */
tls_parse_stoc_renegotiate(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1203 int tls_parse_stoc_renegotiate(SSL *s, PACKET *pkt, unsigned int context,
1204 X509 *x, size_t chainidx)
1205 {
1206 size_t expected_len = s->s3.previous_client_finished_len
1207 + s->s3.previous_server_finished_len;
1208 size_t ilen;
1209 const unsigned char *data;
1210
1211 /* Check for logic errors */
1212 if (!ossl_assert(expected_len == 0
1213 || s->s3.previous_client_finished_len != 0)
1214 || !ossl_assert(expected_len == 0
1215 || s->s3.previous_server_finished_len != 0)) {
1216 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1217 return 0;
1218 }
1219
1220 /* Parse the length byte */
1221 if (!PACKET_get_1_len(pkt, &ilen)) {
1222 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR);
1223 return 0;
1224 }
1225
1226 /* Consistency check */
1227 if (PACKET_remaining(pkt) != ilen) {
1228 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR);
1229 return 0;
1230 }
1231
1232 /* Check that the extension matches */
1233 if (ilen != expected_len) {
1234 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1235 return 0;
1236 }
1237
1238 if (!PACKET_get_bytes(pkt, &data, s->s3.previous_client_finished_len)
1239 || memcmp(data, s->s3.previous_client_finished,
1240 s->s3.previous_client_finished_len) != 0) {
1241 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1242 return 0;
1243 }
1244
1245 if (!PACKET_get_bytes(pkt, &data, s->s3.previous_server_finished_len)
1246 || memcmp(data, s->s3.previous_server_finished,
1247 s->s3.previous_server_finished_len) != 0) {
1248 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1249 return 0;
1250 }
1251 s->s3.send_connection_binding = 1;
1252
1253 return 1;
1254 }
1255
1256 /* Parse the server's max fragment len extension packet */
tls_parse_stoc_maxfragmentlen(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1257 int tls_parse_stoc_maxfragmentlen(SSL *s, PACKET *pkt, unsigned int context,
1258 X509 *x, size_t chainidx)
1259 {
1260 unsigned int value;
1261
1262 if (PACKET_remaining(pkt) != 1 || !PACKET_get_1(pkt, &value)) {
1263 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1264 return 0;
1265 }
1266
1267 /* |value| should contains a valid max-fragment-length code. */
1268 if (!IS_MAX_FRAGMENT_LENGTH_EXT_VALID(value)) {
1269 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1270 SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
1271 return 0;
1272 }
1273
1274 /* Must be the same value as client-configured one who was sent to server */
1275 /*-
1276 * RFC 6066: if a client receives a maximum fragment length negotiation
1277 * response that differs from the length it requested, ...
1278 * It must abort with SSL_AD_ILLEGAL_PARAMETER alert
1279 */
1280 if (value != s->ext.max_fragment_len_mode) {
1281 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1282 SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
1283 return 0;
1284 }
1285
1286 /*
1287 * Maximum Fragment Length Negotiation succeeded.
1288 * The negotiated Maximum Fragment Length is binding now.
1289 */
1290 s->session->ext.max_fragment_len_mode = value;
1291
1292 return 1;
1293 }
1294
tls_parse_stoc_server_name(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1295 int tls_parse_stoc_server_name(SSL *s, PACKET *pkt, unsigned int context,
1296 X509 *x, size_t chainidx)
1297 {
1298 if (s->ext.hostname == NULL) {
1299 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1300 return 0;
1301 }
1302
1303 if (PACKET_remaining(pkt) > 0) {
1304 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1305 return 0;
1306 }
1307
1308 if (!s->hit) {
1309 if (s->session->ext.hostname != NULL) {
1310 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1311 return 0;
1312 }
1313 s->session->ext.hostname = OPENSSL_strdup(s->ext.hostname);
1314 if (s->session->ext.hostname == NULL) {
1315 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1316 return 0;
1317 }
1318 }
1319
1320 return 1;
1321 }
1322
tls_parse_stoc_ec_pt_formats(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1323 int tls_parse_stoc_ec_pt_formats(SSL *s, PACKET *pkt, unsigned int context,
1324 X509 *x, size_t chainidx)
1325 {
1326 size_t ecpointformats_len;
1327 PACKET ecptformatlist;
1328
1329 if (!PACKET_as_length_prefixed_1(pkt, &ecptformatlist)) {
1330 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1331 return 0;
1332 }
1333 if (!s->hit) {
1334 ecpointformats_len = PACKET_remaining(&ecptformatlist);
1335 if (ecpointformats_len == 0) {
1336 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
1337 return 0;
1338 }
1339
1340 s->ext.peer_ecpointformats_len = 0;
1341 OPENSSL_free(s->ext.peer_ecpointformats);
1342 s->ext.peer_ecpointformats = OPENSSL_malloc(ecpointformats_len);
1343 if (s->ext.peer_ecpointformats == NULL) {
1344 s->ext.peer_ecpointformats_len = 0;
1345 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1346 return 0;
1347 }
1348
1349 s->ext.peer_ecpointformats_len = ecpointformats_len;
1350
1351 if (!PACKET_copy_bytes(&ecptformatlist,
1352 s->ext.peer_ecpointformats,
1353 ecpointformats_len)) {
1354 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1355 return 0;
1356 }
1357 }
1358
1359 return 1;
1360 }
1361
tls_parse_stoc_session_ticket(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1362 int tls_parse_stoc_session_ticket(SSL *s, PACKET *pkt, unsigned int context,
1363 X509 *x, size_t chainidx)
1364 {
1365 if (s->ext.session_ticket_cb != NULL &&
1366 !s->ext.session_ticket_cb(s, PACKET_data(pkt),
1367 PACKET_remaining(pkt),
1368 s->ext.session_ticket_cb_arg)) {
1369 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_EXTENSION);
1370 return 0;
1371 }
1372
1373 if (!tls_use_ticket(s)) {
1374 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1375 return 0;
1376 }
1377 if (PACKET_remaining(pkt) > 0) {
1378 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1379 return 0;
1380 }
1381
1382 s->ext.ticket_expected = 1;
1383
1384 return 1;
1385 }
1386
1387 #ifndef OPENSSL_NO_OCSP
tls_parse_stoc_status_request(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1388 int tls_parse_stoc_status_request(SSL *s, PACKET *pkt, unsigned int context,
1389 X509 *x, size_t chainidx)
1390 {
1391 if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) {
1392 /* We ignore this if the server sends a CertificateRequest */
1393 return 1;
1394 }
1395
1396 /*
1397 * MUST only be sent if we've requested a status
1398 * request message. In TLS <= 1.2 it must also be empty.
1399 */
1400 if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) {
1401 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1402 return 0;
1403 }
1404 if (!SSL_IS_TLS13(s) && PACKET_remaining(pkt) > 0) {
1405 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1406 return 0;
1407 }
1408
1409 if (SSL_IS_TLS13(s)) {
1410 /* We only know how to handle this if it's for the first Certificate in
1411 * the chain. We ignore any other responses.
1412 */
1413 if (chainidx != 0)
1414 return 1;
1415
1416 /* SSLfatal() already called */
1417 return tls_process_cert_status_body(s, pkt);
1418 }
1419
1420 /* Set flag to expect CertificateStatus message */
1421 s->ext.status_expected = 1;
1422
1423 return 1;
1424 }
1425 #endif
1426
1427
1428 #ifndef OPENSSL_NO_CT
tls_parse_stoc_sct(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1429 int tls_parse_stoc_sct(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1430 size_t chainidx)
1431 {
1432 if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) {
1433 /* We ignore this if the server sends it in a CertificateRequest */
1434 return 1;
1435 }
1436
1437 /*
1438 * Only take it if we asked for it - i.e if there is no CT validation
1439 * callback set, then a custom extension MAY be processing it, so we
1440 * need to let control continue to flow to that.
1441 */
1442 if (s->ct_validation_callback != NULL) {
1443 size_t size = PACKET_remaining(pkt);
1444
1445 /* Simply copy it off for later processing */
1446 OPENSSL_free(s->ext.scts);
1447 s->ext.scts = NULL;
1448
1449 s->ext.scts_len = (uint16_t)size;
1450 if (size > 0) {
1451 s->ext.scts = OPENSSL_malloc(size);
1452 if (s->ext.scts == NULL) {
1453 s->ext.scts_len = 0;
1454 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
1455 return 0;
1456 }
1457 if (!PACKET_copy_bytes(pkt, s->ext.scts, size)) {
1458 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1459 return 0;
1460 }
1461 }
1462 } else {
1463 ENDPOINT role = (context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0
1464 ? ENDPOINT_CLIENT : ENDPOINT_BOTH;
1465
1466 /*
1467 * If we didn't ask for it then there must be a custom extension,
1468 * otherwise this is unsolicited.
1469 */
1470 if (custom_ext_find(&s->cert->custext, role,
1471 TLSEXT_TYPE_signed_certificate_timestamp,
1472 NULL) == NULL) {
1473 SSLfatal(s, TLS1_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1474 return 0;
1475 }
1476
1477 if (!custom_ext_parse(s, context,
1478 TLSEXT_TYPE_signed_certificate_timestamp,
1479 PACKET_data(pkt), PACKET_remaining(pkt),
1480 x, chainidx)) {
1481 /* SSLfatal already called */
1482 return 0;
1483 }
1484 }
1485
1486 return 1;
1487 }
1488 #endif
1489
1490
1491 #ifndef OPENSSL_NO_NEXTPROTONEG
1492 /*
1493 * ssl_next_proto_validate validates a Next Protocol Negotiation block. No
1494 * elements of zero length are allowed and the set of elements must exactly
1495 * fill the length of the block. Returns 1 on success or 0 on failure.
1496 */
ssl_next_proto_validate(SSL * s,PACKET * pkt)1497 static int ssl_next_proto_validate(SSL *s, PACKET *pkt)
1498 {
1499 PACKET tmp_protocol;
1500
1501 while (PACKET_remaining(pkt)) {
1502 if (!PACKET_get_length_prefixed_1(pkt, &tmp_protocol)
1503 || PACKET_remaining(&tmp_protocol) == 0) {
1504 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1505 return 0;
1506 }
1507 }
1508
1509 return 1;
1510 }
1511
tls_parse_stoc_npn(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1512 int tls_parse_stoc_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1513 size_t chainidx)
1514 {
1515 unsigned char *selected;
1516 unsigned char selected_len;
1517 PACKET tmppkt;
1518
1519 /* Check if we are in a renegotiation. If so ignore this extension */
1520 if (!SSL_IS_FIRST_HANDSHAKE(s))
1521 return 1;
1522
1523 /* We must have requested it. */
1524 if (s->ctx->ext.npn_select_cb == NULL) {
1525 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1526 return 0;
1527 }
1528
1529 /* The data must be valid */
1530 tmppkt = *pkt;
1531 if (!ssl_next_proto_validate(s, &tmppkt)) {
1532 /* SSLfatal() already called */
1533 return 0;
1534 }
1535 if (s->ctx->ext.npn_select_cb(s, &selected, &selected_len,
1536 PACKET_data(pkt),
1537 PACKET_remaining(pkt),
1538 s->ctx->ext.npn_select_cb_arg) !=
1539 SSL_TLSEXT_ERR_OK
1540 || selected_len == 0) {
1541 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_EXTENSION);
1542 return 0;
1543 }
1544
1545 /*
1546 * Could be non-NULL if server has sent multiple NPN extensions in
1547 * a single Serverhello
1548 */
1549 OPENSSL_free(s->ext.npn);
1550 s->ext.npn = OPENSSL_malloc(selected_len);
1551 if (s->ext.npn == NULL) {
1552 s->ext.npn_len = 0;
1553 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1554 return 0;
1555 }
1556
1557 memcpy(s->ext.npn, selected, selected_len);
1558 s->ext.npn_len = selected_len;
1559 s->s3.npn_seen = 1;
1560
1561 return 1;
1562 }
1563 #endif
1564
tls_parse_stoc_alpn(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1565 int tls_parse_stoc_alpn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1566 size_t chainidx)
1567 {
1568 size_t len;
1569 PACKET confpkt, protpkt;
1570 int valid = 0;
1571
1572 /* We must have requested it. */
1573 if (!s->s3.alpn_sent) {
1574 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1575 return 0;
1576 }
1577 /*-
1578 * The extension data consists of:
1579 * uint16 list_length
1580 * uint8 proto_length;
1581 * uint8 proto[proto_length];
1582 */
1583 if (!PACKET_get_net_2_len(pkt, &len)
1584 || PACKET_remaining(pkt) != len || !PACKET_get_1_len(pkt, &len)
1585 || PACKET_remaining(pkt) != len) {
1586 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1587 return 0;
1588 }
1589
1590 /* It must be a protocol that we sent */
1591 if (!PACKET_buf_init(&confpkt, s->ext.alpn, s->ext.alpn_len)) {
1592 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1593 return 0;
1594 }
1595 while (PACKET_get_length_prefixed_1(&confpkt, &protpkt)) {
1596 if (PACKET_remaining(&protpkt) != len)
1597 continue;
1598 if (memcmp(PACKET_data(pkt), PACKET_data(&protpkt), len) == 0) {
1599 /* Valid protocol found */
1600 valid = 1;
1601 break;
1602 }
1603 }
1604
1605 if (!valid) {
1606 /* The protocol sent from the server does not match one we advertised */
1607 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1608 return 0;
1609 }
1610
1611 OPENSSL_free(s->s3.alpn_selected);
1612 s->s3.alpn_selected = OPENSSL_malloc(len);
1613 if (s->s3.alpn_selected == NULL) {
1614 s->s3.alpn_selected_len = 0;
1615 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1616 return 0;
1617 }
1618 if (!PACKET_copy_bytes(pkt, s->s3.alpn_selected, len)) {
1619 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1620 return 0;
1621 }
1622 s->s3.alpn_selected_len = len;
1623
1624 if (s->session->ext.alpn_selected == NULL
1625 || s->session->ext.alpn_selected_len != len
1626 || memcmp(s->session->ext.alpn_selected, s->s3.alpn_selected, len)
1627 != 0) {
1628 /* ALPN not consistent with the old session so cannot use early_data */
1629 s->ext.early_data_ok = 0;
1630 }
1631 if (!s->hit) {
1632 /*
1633 * This is a new session and so alpn_selected should have been
1634 * initialised to NULL. We should update it with the selected ALPN.
1635 */
1636 if (!ossl_assert(s->session->ext.alpn_selected == NULL)) {
1637 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1638 return 0;
1639 }
1640 s->session->ext.alpn_selected =
1641 OPENSSL_memdup(s->s3.alpn_selected, s->s3.alpn_selected_len);
1642 if (s->session->ext.alpn_selected == NULL) {
1643 s->session->ext.alpn_selected_len = 0;
1644 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1645 return 0;
1646 }
1647 s->session->ext.alpn_selected_len = s->s3.alpn_selected_len;
1648 }
1649
1650 return 1;
1651 }
1652
1653 #ifndef OPENSSL_NO_SRTP
tls_parse_stoc_use_srtp(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1654 int tls_parse_stoc_use_srtp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1655 size_t chainidx)
1656 {
1657 unsigned int id, ct, mki;
1658 int i;
1659 STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
1660 SRTP_PROTECTION_PROFILE *prof;
1661
1662 if (!PACKET_get_net_2(pkt, &ct) || ct != 2
1663 || !PACKET_get_net_2(pkt, &id)
1664 || !PACKET_get_1(pkt, &mki)
1665 || PACKET_remaining(pkt) != 0) {
1666 SSLfatal(s, SSL_AD_DECODE_ERROR,
1667 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
1668 return 0;
1669 }
1670
1671 if (mki != 0) {
1672 /* Must be no MKI, since we never offer one */
1673 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_SRTP_MKI_VALUE);
1674 return 0;
1675 }
1676
1677 /* Throw an error if the server gave us an unsolicited extension */
1678 clnt = SSL_get_srtp_profiles(s);
1679 if (clnt == NULL) {
1680 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_NO_SRTP_PROFILES);
1681 return 0;
1682 }
1683
1684 /*
1685 * Check to see if the server gave us something we support (and
1686 * presumably offered)
1687 */
1688 for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
1689 prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
1690
1691 if (prof->id == id) {
1692 s->srtp_profile = prof;
1693 return 1;
1694 }
1695 }
1696
1697 SSLfatal(s, SSL_AD_DECODE_ERROR,
1698 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
1699 return 0;
1700 }
1701 #endif
1702
tls_parse_stoc_etm(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1703 int tls_parse_stoc_etm(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1704 size_t chainidx)
1705 {
1706 /* Ignore if inappropriate ciphersuite */
1707 if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
1708 && s->s3.tmp.new_cipher->algorithm_mac != SSL_AEAD
1709 && s->s3.tmp.new_cipher->algorithm_enc != SSL_RC4
1710 && s->s3.tmp.new_cipher->algorithm_enc != SSL_eGOST2814789CNT
1711 && s->s3.tmp.new_cipher->algorithm_enc != SSL_eGOST2814789CNT12
1712 && s->s3.tmp.new_cipher->algorithm_enc != SSL_MAGMA
1713 && s->s3.tmp.new_cipher->algorithm_enc != SSL_KUZNYECHIK)
1714 s->ext.use_etm = 1;
1715
1716 return 1;
1717 }
1718
tls_parse_stoc_ems(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1719 int tls_parse_stoc_ems(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1720 size_t chainidx)
1721 {
1722 if (s->options & SSL_OP_NO_EXTENDED_MASTER_SECRET)
1723 return 1;
1724 s->s3.flags |= TLS1_FLAGS_RECEIVED_EXTMS;
1725 if (!s->hit)
1726 s->session->flags |= SSL_SESS_FLAG_EXTMS;
1727
1728 return 1;
1729 }
1730
tls_parse_stoc_supported_versions(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1731 int tls_parse_stoc_supported_versions(SSL *s, PACKET *pkt, unsigned int context,
1732 X509 *x, size_t chainidx)
1733 {
1734 unsigned int version;
1735
1736 if (!PACKET_get_net_2(pkt, &version)
1737 || PACKET_remaining(pkt) != 0) {
1738 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1739 return 0;
1740 }
1741
1742 /*
1743 * The only protocol version we support which is valid in this extension in
1744 * a ServerHello is TLSv1.3 therefore we shouldn't be getting anything else.
1745 */
1746 if (version != TLS1_3_VERSION) {
1747 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1748 SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
1749 return 0;
1750 }
1751
1752 /* We ignore this extension for HRRs except to sanity check it */
1753 if (context == SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST)
1754 return 1;
1755
1756 /* We just set it here. We validate it in ssl_choose_client_version */
1757 s->version = version;
1758
1759 return 1;
1760 }
1761
tls_parse_stoc_key_share(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1762 int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1763 size_t chainidx)
1764 {
1765 #ifndef OPENSSL_NO_TLS1_3
1766 unsigned int group_id;
1767 PACKET encoded_pt;
1768 EVP_PKEY *ckey = s->s3.tmp.pkey, *skey = NULL;
1769 const TLS_GROUP_INFO *ginf = NULL;
1770
1771 /* Sanity check */
1772 if (ckey == NULL || s->s3.peer_tmp != NULL) {
1773 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1774 return 0;
1775 }
1776
1777 if (!PACKET_get_net_2(pkt, &group_id)) {
1778 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1779 return 0;
1780 }
1781
1782 if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0) {
1783 const uint16_t *pgroups = NULL;
1784 size_t i, num_groups;
1785
1786 if (PACKET_remaining(pkt) != 0) {
1787 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1788 return 0;
1789 }
1790
1791 /*
1792 * It is an error if the HelloRetryRequest wants a key_share that we
1793 * already sent in the first ClientHello
1794 */
1795 if (group_id == s->s3.group_id) {
1796 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1797 return 0;
1798 }
1799
1800 /* Validate the selected group is one we support */
1801 tls1_get_supported_groups(s, &pgroups, &num_groups);
1802 for (i = 0; i < num_groups; i++) {
1803 if (group_id == pgroups[i])
1804 break;
1805 }
1806 if (i >= num_groups
1807 || !tls_group_allowed(s, group_id, SSL_SECOP_CURVE_SUPPORTED)
1808 || !tls_valid_group(s, group_id, TLS1_3_VERSION, TLS1_3_VERSION,
1809 0, NULL)) {
1810 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1811 return 0;
1812 }
1813
1814 s->s3.group_id = group_id;
1815 EVP_PKEY_free(s->s3.tmp.pkey);
1816 s->s3.tmp.pkey = NULL;
1817 return 1;
1818 }
1819
1820 if (group_id != s->s3.group_id) {
1821 /*
1822 * This isn't for the group that we sent in the original
1823 * key_share!
1824 */
1825 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1826 return 0;
1827 }
1828 /* Retain this group in the SSL_SESSION */
1829 if (!s->hit) {
1830 s->session->kex_group = group_id;
1831 } else if (group_id != s->session->kex_group) {
1832 /*
1833 * If this is a resumption but changed what group was used, we need
1834 * to record the new group in the session, but the session is not
1835 * a new session and could be in use by other threads. So, make
1836 * a copy of the session to record the new information so that it's
1837 * useful for any sessions resumed from tickets issued on this
1838 * connection.
1839 */
1840 SSL_SESSION *new_sess;
1841
1842 if ((new_sess = ssl_session_dup(s->session, 0)) == NULL) {
1843 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
1844 return 0;
1845 }
1846 SSL_SESSION_free(s->session);
1847 s->session = new_sess;
1848 s->session->kex_group = group_id;
1849 }
1850
1851 if ((ginf = tls1_group_id_lookup(s->ctx, group_id)) == NULL) {
1852 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1853 return 0;
1854 }
1855
1856 if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt)
1857 || PACKET_remaining(&encoded_pt) == 0) {
1858 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1859 return 0;
1860 }
1861
1862 if (!ginf->is_kem) {
1863 /* Regular KEX */
1864 skey = EVP_PKEY_new();
1865 if (skey == NULL || EVP_PKEY_copy_parameters(skey, ckey) <= 0) {
1866 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
1867 EVP_PKEY_free(skey);
1868 return 0;
1869 }
1870
1871 if (tls13_set_encoded_pub_key(skey, PACKET_data(&encoded_pt),
1872 PACKET_remaining(&encoded_pt)) <= 0) {
1873 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_ECPOINT);
1874 EVP_PKEY_free(skey);
1875 return 0;
1876 }
1877
1878 if (ssl_derive(s, ckey, skey, 1) == 0) {
1879 /* SSLfatal() already called */
1880 EVP_PKEY_free(skey);
1881 return 0;
1882 }
1883 s->s3.peer_tmp = skey;
1884 } else {
1885 /* KEM Mode */
1886 const unsigned char *ct = PACKET_data(&encoded_pt);
1887 size_t ctlen = PACKET_remaining(&encoded_pt);
1888
1889 if (ssl_decapsulate(s, ckey, ct, ctlen, 1) == 0) {
1890 /* SSLfatal() already called */
1891 return 0;
1892 }
1893 }
1894 s->s3.did_kex = 1;
1895 #endif
1896
1897 return 1;
1898 }
1899
tls_parse_stoc_cookie(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1900 int tls_parse_stoc_cookie(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1901 size_t chainidx)
1902 {
1903 PACKET cookie;
1904
1905 if (!PACKET_as_length_prefixed_2(pkt, &cookie)
1906 || !PACKET_memdup(&cookie, &s->ext.tls13_cookie,
1907 &s->ext.tls13_cookie_len)) {
1908 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1909 return 0;
1910 }
1911
1912 return 1;
1913 }
1914
tls_parse_stoc_early_data(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1915 int tls_parse_stoc_early_data(SSL *s, PACKET *pkt, unsigned int context,
1916 X509 *x, size_t chainidx)
1917 {
1918 if (context == SSL_EXT_TLS1_3_NEW_SESSION_TICKET) {
1919 unsigned long max_early_data;
1920
1921 if (!PACKET_get_net_4(pkt, &max_early_data)
1922 || PACKET_remaining(pkt) != 0) {
1923 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_INVALID_MAX_EARLY_DATA);
1924 return 0;
1925 }
1926
1927 s->session->ext.max_early_data = max_early_data;
1928
1929 return 1;
1930 }
1931
1932 if (PACKET_remaining(pkt) != 0) {
1933 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1934 return 0;
1935 }
1936
1937 if (!s->ext.early_data_ok
1938 || !s->hit) {
1939 /*
1940 * If we get here then we didn't send early data, or we didn't resume
1941 * using the first identity, or the SNI/ALPN is not consistent so the
1942 * server should not be accepting it.
1943 */
1944 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_EXTENSION);
1945 return 0;
1946 }
1947
1948 s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
1949
1950 return 1;
1951 }
1952
tls_parse_stoc_psk(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1953 int tls_parse_stoc_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1954 size_t chainidx)
1955 {
1956 #ifndef OPENSSL_NO_TLS1_3
1957 unsigned int identity;
1958
1959 if (!PACKET_get_net_2(pkt, &identity) || PACKET_remaining(pkt) != 0) {
1960 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1961 return 0;
1962 }
1963
1964 if (identity >= (unsigned int)s->ext.tick_identity) {
1965 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_PSK_IDENTITY);
1966 return 0;
1967 }
1968
1969 /*
1970 * Session resumption tickets are always sent before PSK tickets. If the
1971 * ticket index is 0 then it must be for a session resumption ticket if we
1972 * sent two tickets, or if we didn't send a PSK ticket.
1973 */
1974 if (identity == 0 && (s->psksession == NULL || s->ext.tick_identity == 2)) {
1975 s->hit = 1;
1976 SSL_SESSION_free(s->psksession);
1977 s->psksession = NULL;
1978 return 1;
1979 }
1980
1981 if (s->psksession == NULL) {
1982 /* Should never happen */
1983 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1984 return 0;
1985 }
1986
1987 /*
1988 * If we used the external PSK for sending early_data then s->early_secret
1989 * is already set up, so don't overwrite it. Otherwise we copy the
1990 * early_secret across that we generated earlier.
1991 */
1992 if ((s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
1993 && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
1994 || s->session->ext.max_early_data > 0
1995 || s->psksession->ext.max_early_data == 0)
1996 memcpy(s->early_secret, s->psksession->early_secret, EVP_MAX_MD_SIZE);
1997
1998 SSL_SESSION_free(s->session);
1999 s->session = s->psksession;
2000 s->psksession = NULL;
2001 s->hit = 1;
2002 /* Early data is only allowed if we used the first ticket */
2003 if (identity != 0)
2004 s->ext.early_data_ok = 0;
2005 #endif
2006
2007 return 1;
2008 }
2009