1 /*
2 * Copyright 2016-2021 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 curve_id = pgroups[i];
683 break;
684 }
685 }
686
687 if (curve_id == 0) {
688 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_KEY_SHARE);
689 return EXT_RETURN_FAIL;
690 }
691
692 if (!add_key_share(s, pkt, curve_id)) {
693 /* SSLfatal() already called */
694 return EXT_RETURN_FAIL;
695 }
696
697 if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
698 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
699 return EXT_RETURN_FAIL;
700 }
701 return EXT_RETURN_SENT;
702 #else
703 return EXT_RETURN_NOT_SENT;
704 #endif
705 }
706
tls_construct_ctos_cookie(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)707 EXT_RETURN tls_construct_ctos_cookie(SSL *s, WPACKET *pkt, unsigned int context,
708 X509 *x, size_t chainidx)
709 {
710 EXT_RETURN ret = EXT_RETURN_FAIL;
711
712 /* Should only be set if we've had an HRR */
713 if (s->ext.tls13_cookie_len == 0)
714 return EXT_RETURN_NOT_SENT;
715
716 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_cookie)
717 /* Extension data sub-packet */
718 || !WPACKET_start_sub_packet_u16(pkt)
719 || !WPACKET_sub_memcpy_u16(pkt, s->ext.tls13_cookie,
720 s->ext.tls13_cookie_len)
721 || !WPACKET_close(pkt)) {
722 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
723 goto end;
724 }
725
726 ret = EXT_RETURN_SENT;
727 end:
728 OPENSSL_free(s->ext.tls13_cookie);
729 s->ext.tls13_cookie = NULL;
730 s->ext.tls13_cookie_len = 0;
731
732 return ret;
733 }
734
tls_construct_ctos_early_data(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)735 EXT_RETURN tls_construct_ctos_early_data(SSL *s, WPACKET *pkt,
736 unsigned int context, X509 *x,
737 size_t chainidx)
738 {
739 #ifndef OPENSSL_NO_PSK
740 char identity[PSK_MAX_IDENTITY_LEN + 1];
741 #endif /* OPENSSL_NO_PSK */
742 const unsigned char *id = NULL;
743 size_t idlen = 0;
744 SSL_SESSION *psksess = NULL;
745 SSL_SESSION *edsess = NULL;
746 const EVP_MD *handmd = NULL;
747
748 if (s->hello_retry_request == SSL_HRR_PENDING)
749 handmd = ssl_handshake_md(s);
750
751 if (s->psk_use_session_cb != NULL
752 && (!s->psk_use_session_cb(s, handmd, &id, &idlen, &psksess)
753 || (psksess != NULL
754 && psksess->ssl_version != TLS1_3_VERSION))) {
755 SSL_SESSION_free(psksess);
756 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
757 return EXT_RETURN_FAIL;
758 }
759
760 #ifndef OPENSSL_NO_PSK
761 if (psksess == NULL && s->psk_client_callback != NULL) {
762 unsigned char psk[PSK_MAX_PSK_LEN];
763 size_t psklen = 0;
764
765 memset(identity, 0, sizeof(identity));
766 psklen = s->psk_client_callback(s, NULL, identity, sizeof(identity) - 1,
767 psk, sizeof(psk));
768
769 if (psklen > PSK_MAX_PSK_LEN) {
770 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, ERR_R_INTERNAL_ERROR);
771 return EXT_RETURN_FAIL;
772 } else if (psklen > 0) {
773 const unsigned char tls13_aes128gcmsha256_id[] = { 0x13, 0x01 };
774 const SSL_CIPHER *cipher;
775
776 idlen = strlen(identity);
777 if (idlen > PSK_MAX_IDENTITY_LEN) {
778 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
779 return EXT_RETURN_FAIL;
780 }
781 id = (unsigned char *)identity;
782
783 /*
784 * We found a PSK using an old style callback. We don't know
785 * the digest so we default to SHA256 as per the TLSv1.3 spec
786 */
787 cipher = SSL_CIPHER_find(s, tls13_aes128gcmsha256_id);
788 if (cipher == NULL) {
789 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
790 return EXT_RETURN_FAIL;
791 }
792
793 psksess = SSL_SESSION_new();
794 if (psksess == NULL
795 || !SSL_SESSION_set1_master_key(psksess, psk, psklen)
796 || !SSL_SESSION_set_cipher(psksess, cipher)
797 || !SSL_SESSION_set_protocol_version(psksess, TLS1_3_VERSION)) {
798 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
799 OPENSSL_cleanse(psk, psklen);
800 return EXT_RETURN_FAIL;
801 }
802 OPENSSL_cleanse(psk, psklen);
803 }
804 }
805 #endif /* OPENSSL_NO_PSK */
806
807 SSL_SESSION_free(s->psksession);
808 s->psksession = psksess;
809 if (psksess != NULL) {
810 OPENSSL_free(s->psksession_id);
811 s->psksession_id = OPENSSL_memdup(id, idlen);
812 if (s->psksession_id == NULL) {
813 s->psksession_id_len = 0;
814 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
815 return EXT_RETURN_FAIL;
816 }
817 s->psksession_id_len = idlen;
818 }
819
820 if (s->early_data_state != SSL_EARLY_DATA_CONNECTING
821 || (s->session->ext.max_early_data == 0
822 && (psksess == NULL || psksess->ext.max_early_data == 0))) {
823 s->max_early_data = 0;
824 return EXT_RETURN_NOT_SENT;
825 }
826 edsess = s->session->ext.max_early_data != 0 ? s->session : psksess;
827 s->max_early_data = edsess->ext.max_early_data;
828
829 if (edsess->ext.hostname != NULL) {
830 if (s->ext.hostname == NULL
831 || (s->ext.hostname != NULL
832 && strcmp(s->ext.hostname, edsess->ext.hostname) != 0)) {
833 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
834 SSL_R_INCONSISTENT_EARLY_DATA_SNI);
835 return EXT_RETURN_FAIL;
836 }
837 }
838
839 if ((s->ext.alpn == NULL && edsess->ext.alpn_selected != NULL)) {
840 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
841 return EXT_RETURN_FAIL;
842 }
843
844 /*
845 * Verify that we are offering an ALPN protocol consistent with the early
846 * data.
847 */
848 if (edsess->ext.alpn_selected != NULL) {
849 PACKET prots, alpnpkt;
850 int found = 0;
851
852 if (!PACKET_buf_init(&prots, s->ext.alpn, s->ext.alpn_len)) {
853 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
854 return EXT_RETURN_FAIL;
855 }
856 while (PACKET_get_length_prefixed_1(&prots, &alpnpkt)) {
857 if (PACKET_equal(&alpnpkt, edsess->ext.alpn_selected,
858 edsess->ext.alpn_selected_len)) {
859 found = 1;
860 break;
861 }
862 }
863 if (!found) {
864 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
865 SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
866 return EXT_RETURN_FAIL;
867 }
868 }
869
870 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_early_data)
871 || !WPACKET_start_sub_packet_u16(pkt)
872 || !WPACKET_close(pkt)) {
873 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
874 return EXT_RETURN_FAIL;
875 }
876
877 /*
878 * We set this to rejected here. Later, if the server acknowledges the
879 * extension, we set it to accepted.
880 */
881 s->ext.early_data = SSL_EARLY_DATA_REJECTED;
882 s->ext.early_data_ok = 1;
883
884 return EXT_RETURN_SENT;
885 }
886
887 #define F5_WORKAROUND_MIN_MSG_LEN 0xff
888 #define F5_WORKAROUND_MAX_MSG_LEN 0x200
889
890 /*
891 * PSK pre binder overhead =
892 * 2 bytes for TLSEXT_TYPE_psk
893 * 2 bytes for extension length
894 * 2 bytes for identities list length
895 * 2 bytes for identity length
896 * 4 bytes for obfuscated_ticket_age
897 * 2 bytes for binder list length
898 * 1 byte for binder length
899 * The above excludes the number of bytes for the identity itself and the
900 * subsequent binder bytes
901 */
902 #define PSK_PRE_BINDER_OVERHEAD (2 + 2 + 2 + 2 + 4 + 2 + 1)
903
tls_construct_ctos_padding(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)904 EXT_RETURN tls_construct_ctos_padding(SSL *s, WPACKET *pkt,
905 unsigned int context, X509 *x,
906 size_t chainidx)
907 {
908 unsigned char *padbytes;
909 size_t hlen;
910
911 if ((s->options & SSL_OP_TLSEXT_PADDING) == 0)
912 return EXT_RETURN_NOT_SENT;
913
914 /*
915 * Add padding to workaround bugs in F5 terminators. See RFC7685.
916 * This code calculates the length of all extensions added so far but
917 * excludes the PSK extension (because that MUST be written last). Therefore
918 * this extension MUST always appear second to last.
919 */
920 if (!WPACKET_get_total_written(pkt, &hlen)) {
921 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
922 return EXT_RETURN_FAIL;
923 }
924
925 /*
926 * If we're going to send a PSK then that will be written out after this
927 * extension, so we need to calculate how long it is going to be.
928 */
929 if (s->session->ssl_version == TLS1_3_VERSION
930 && s->session->ext.ticklen != 0
931 && s->session->cipher != NULL) {
932 const EVP_MD *md = ssl_md(s->ctx, s->session->cipher->algorithm2);
933
934 if (md != NULL) {
935 /*
936 * Add the fixed PSK overhead, the identity length and the binder
937 * length.
938 */
939 hlen += PSK_PRE_BINDER_OVERHEAD + s->session->ext.ticklen
940 + EVP_MD_get_size(md);
941 }
942 }
943
944 if (hlen > F5_WORKAROUND_MIN_MSG_LEN && hlen < F5_WORKAROUND_MAX_MSG_LEN) {
945 /* Calculate the amount of padding we need to add */
946 hlen = F5_WORKAROUND_MAX_MSG_LEN - hlen;
947
948 /*
949 * Take off the size of extension header itself (2 bytes for type and
950 * 2 bytes for length bytes), but ensure that the extension is at least
951 * 1 byte long so as not to have an empty extension last (WebSphere 7.x,
952 * 8.x are intolerant of that condition)
953 */
954 if (hlen > 4)
955 hlen -= 4;
956 else
957 hlen = 1;
958
959 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_padding)
960 || !WPACKET_sub_allocate_bytes_u16(pkt, hlen, &padbytes)) {
961 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
962 return EXT_RETURN_FAIL;
963 }
964 memset(padbytes, 0, hlen);
965 }
966
967 return EXT_RETURN_SENT;
968 }
969
970 /*
971 * Construct the pre_shared_key extension
972 */
tls_construct_ctos_psk(SSL * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)973 EXT_RETURN tls_construct_ctos_psk(SSL *s, WPACKET *pkt, unsigned int context,
974 X509 *x, size_t chainidx)
975 {
976 #ifndef OPENSSL_NO_TLS1_3
977 uint32_t now, agesec, agems = 0;
978 size_t reshashsize = 0, pskhashsize = 0, binderoffset, msglen;
979 unsigned char *resbinder = NULL, *pskbinder = NULL, *msgstart = NULL;
980 const EVP_MD *handmd = NULL, *mdres = NULL, *mdpsk = NULL;
981 int dores = 0;
982
983 s->ext.tick_identity = 0;
984
985 /*
986 * Note: At this stage of the code we only support adding a single
987 * resumption PSK. If we add support for multiple PSKs then the length
988 * calculations in the padding extension will need to be adjusted.
989 */
990
991 /*
992 * If this is an incompatible or new session then we have nothing to resume
993 * so don't add this extension.
994 */
995 if (s->session->ssl_version != TLS1_3_VERSION
996 || (s->session->ext.ticklen == 0 && s->psksession == NULL))
997 return EXT_RETURN_NOT_SENT;
998
999 if (s->hello_retry_request == SSL_HRR_PENDING)
1000 handmd = ssl_handshake_md(s);
1001
1002 if (s->session->ext.ticklen != 0) {
1003 /* Get the digest associated with the ciphersuite in the session */
1004 if (s->session->cipher == NULL) {
1005 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1006 return EXT_RETURN_FAIL;
1007 }
1008 mdres = ssl_md(s->ctx, s->session->cipher->algorithm2);
1009 if (mdres == NULL) {
1010 /*
1011 * Don't recognize this cipher so we can't use the session.
1012 * Ignore it
1013 */
1014 goto dopsksess;
1015 }
1016
1017 if (s->hello_retry_request == SSL_HRR_PENDING && mdres != handmd) {
1018 /*
1019 * Selected ciphersuite hash does not match the hash for the session
1020 * so we can't use it.
1021 */
1022 goto dopsksess;
1023 }
1024
1025 /*
1026 * Technically the C standard just says time() returns a time_t and says
1027 * nothing about the encoding of that type. In practice most
1028 * implementations follow POSIX which holds it as an integral type in
1029 * seconds since epoch. We've already made the assumption that we can do
1030 * this in multiple places in the code, so portability shouldn't be an
1031 * issue.
1032 */
1033 now = (uint32_t)time(NULL);
1034 agesec = now - (uint32_t)s->session->time;
1035 /*
1036 * We calculate the age in seconds but the server may work in ms. Due to
1037 * rounding errors we could overestimate the age by up to 1s. It is
1038 * better to underestimate it. Otherwise, if the RTT is very short, when
1039 * the server calculates the age reported by the client it could be
1040 * bigger than the age calculated on the server - which should never
1041 * happen.
1042 */
1043 if (agesec > 0)
1044 agesec--;
1045
1046 if (s->session->ext.tick_lifetime_hint < agesec) {
1047 /* Ticket is too old. Ignore it. */
1048 goto dopsksess;
1049 }
1050
1051 /*
1052 * Calculate age in ms. We're just doing it to nearest second. Should be
1053 * good enough.
1054 */
1055 agems = agesec * (uint32_t)1000;
1056
1057 if (agesec != 0 && agems / (uint32_t)1000 != agesec) {
1058 /*
1059 * Overflow. Shouldn't happen unless this is a *really* old session.
1060 * If so we just ignore it.
1061 */
1062 goto dopsksess;
1063 }
1064
1065 /*
1066 * Obfuscate the age. Overflow here is fine, this addition is supposed
1067 * to be mod 2^32.
1068 */
1069 agems += s->session->ext.tick_age_add;
1070
1071 reshashsize = EVP_MD_get_size(mdres);
1072 s->ext.tick_identity++;
1073 dores = 1;
1074 }
1075
1076 dopsksess:
1077 if (!dores && s->psksession == NULL)
1078 return EXT_RETURN_NOT_SENT;
1079
1080 if (s->psksession != NULL) {
1081 mdpsk = ssl_md(s->ctx, s->psksession->cipher->algorithm2);
1082 if (mdpsk == NULL) {
1083 /*
1084 * Don't recognize this cipher so we can't use the session.
1085 * If this happens it's an application bug.
1086 */
1087 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1088 return EXT_RETURN_FAIL;
1089 }
1090
1091 if (s->hello_retry_request == SSL_HRR_PENDING && mdpsk != handmd) {
1092 /*
1093 * Selected ciphersuite hash does not match the hash for the PSK
1094 * session. This is an application bug.
1095 */
1096 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1097 return EXT_RETURN_FAIL;
1098 }
1099
1100 pskhashsize = EVP_MD_get_size(mdpsk);
1101 }
1102
1103 /* Create the extension, but skip over the binder for now */
1104 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk)
1105 || !WPACKET_start_sub_packet_u16(pkt)
1106 || !WPACKET_start_sub_packet_u16(pkt)) {
1107 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1108 return EXT_RETURN_FAIL;
1109 }
1110
1111 if (dores) {
1112 if (!WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick,
1113 s->session->ext.ticklen)
1114 || !WPACKET_put_bytes_u32(pkt, agems)) {
1115 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1116 return EXT_RETURN_FAIL;
1117 }
1118 }
1119
1120 if (s->psksession != NULL) {
1121 if (!WPACKET_sub_memcpy_u16(pkt, s->psksession_id,
1122 s->psksession_id_len)
1123 || !WPACKET_put_bytes_u32(pkt, 0)) {
1124 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1125 return EXT_RETURN_FAIL;
1126 }
1127 s->ext.tick_identity++;
1128 }
1129
1130 if (!WPACKET_close(pkt)
1131 || !WPACKET_get_total_written(pkt, &binderoffset)
1132 || !WPACKET_start_sub_packet_u16(pkt)
1133 || (dores
1134 && !WPACKET_sub_allocate_bytes_u8(pkt, reshashsize, &resbinder))
1135 || (s->psksession != NULL
1136 && !WPACKET_sub_allocate_bytes_u8(pkt, pskhashsize, &pskbinder))
1137 || !WPACKET_close(pkt)
1138 || !WPACKET_close(pkt)
1139 || !WPACKET_get_total_written(pkt, &msglen)
1140 /*
1141 * We need to fill in all the sub-packet lengths now so we can
1142 * calculate the HMAC of the message up to the binders
1143 */
1144 || !WPACKET_fill_lengths(pkt)) {
1145 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1146 return EXT_RETURN_FAIL;
1147 }
1148
1149 msgstart = WPACKET_get_curr(pkt) - msglen;
1150
1151 if (dores
1152 && tls_psk_do_binder(s, mdres, msgstart, binderoffset, NULL,
1153 resbinder, s->session, 1, 0) != 1) {
1154 /* SSLfatal() already called */
1155 return EXT_RETURN_FAIL;
1156 }
1157
1158 if (s->psksession != NULL
1159 && tls_psk_do_binder(s, mdpsk, msgstart, binderoffset, NULL,
1160 pskbinder, s->psksession, 1, 1) != 1) {
1161 /* SSLfatal() already called */
1162 return EXT_RETURN_FAIL;
1163 }
1164
1165 return EXT_RETURN_SENT;
1166 #else
1167 return EXT_RETURN_NOT_SENT;
1168 #endif
1169 }
1170
tls_construct_ctos_post_handshake_auth(SSL * s,WPACKET * pkt,ossl_unused unsigned int context,ossl_unused X509 * x,ossl_unused size_t chainidx)1171 EXT_RETURN tls_construct_ctos_post_handshake_auth(SSL *s, WPACKET *pkt,
1172 ossl_unused unsigned int context,
1173 ossl_unused X509 *x,
1174 ossl_unused size_t chainidx)
1175 {
1176 #ifndef OPENSSL_NO_TLS1_3
1177 if (!s->pha_enabled)
1178 return EXT_RETURN_NOT_SENT;
1179
1180 /* construct extension - 0 length, no contents */
1181 if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_post_handshake_auth)
1182 || !WPACKET_start_sub_packet_u16(pkt)
1183 || !WPACKET_close(pkt)) {
1184 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1185 return EXT_RETURN_FAIL;
1186 }
1187
1188 s->post_handshake_auth = SSL_PHA_EXT_SENT;
1189
1190 return EXT_RETURN_SENT;
1191 #else
1192 return EXT_RETURN_NOT_SENT;
1193 #endif
1194 }
1195
1196
1197 /*
1198 * Parse the server's renegotiation binding and abort if it's not right
1199 */
tls_parse_stoc_renegotiate(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1200 int tls_parse_stoc_renegotiate(SSL *s, PACKET *pkt, unsigned int context,
1201 X509 *x, size_t chainidx)
1202 {
1203 size_t expected_len = s->s3.previous_client_finished_len
1204 + s->s3.previous_server_finished_len;
1205 size_t ilen;
1206 const unsigned char *data;
1207
1208 /* Check for logic errors */
1209 if (!ossl_assert(expected_len == 0
1210 || s->s3.previous_client_finished_len != 0)
1211 || !ossl_assert(expected_len == 0
1212 || s->s3.previous_server_finished_len != 0)) {
1213 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1214 return 0;
1215 }
1216
1217 /* Parse the length byte */
1218 if (!PACKET_get_1_len(pkt, &ilen)) {
1219 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR);
1220 return 0;
1221 }
1222
1223 /* Consistency check */
1224 if (PACKET_remaining(pkt) != ilen) {
1225 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR);
1226 return 0;
1227 }
1228
1229 /* Check that the extension matches */
1230 if (ilen != expected_len) {
1231 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1232 return 0;
1233 }
1234
1235 if (!PACKET_get_bytes(pkt, &data, s->s3.previous_client_finished_len)
1236 || memcmp(data, s->s3.previous_client_finished,
1237 s->s3.previous_client_finished_len) != 0) {
1238 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1239 return 0;
1240 }
1241
1242 if (!PACKET_get_bytes(pkt, &data, s->s3.previous_server_finished_len)
1243 || memcmp(data, s->s3.previous_server_finished,
1244 s->s3.previous_server_finished_len) != 0) {
1245 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1246 return 0;
1247 }
1248 s->s3.send_connection_binding = 1;
1249
1250 return 1;
1251 }
1252
1253 /* 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)1254 int tls_parse_stoc_maxfragmentlen(SSL *s, PACKET *pkt, unsigned int context,
1255 X509 *x, size_t chainidx)
1256 {
1257 unsigned int value;
1258
1259 if (PACKET_remaining(pkt) != 1 || !PACKET_get_1(pkt, &value)) {
1260 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1261 return 0;
1262 }
1263
1264 /* |value| should contains a valid max-fragment-length code. */
1265 if (!IS_MAX_FRAGMENT_LENGTH_EXT_VALID(value)) {
1266 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1267 SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
1268 return 0;
1269 }
1270
1271 /* Must be the same value as client-configured one who was sent to server */
1272 /*-
1273 * RFC 6066: if a client receives a maximum fragment length negotiation
1274 * response that differs from the length it requested, ...
1275 * It must abort with SSL_AD_ILLEGAL_PARAMETER alert
1276 */
1277 if (value != s->ext.max_fragment_len_mode) {
1278 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1279 SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
1280 return 0;
1281 }
1282
1283 /*
1284 * Maximum Fragment Length Negotiation succeeded.
1285 * The negotiated Maximum Fragment Length is binding now.
1286 */
1287 s->session->ext.max_fragment_len_mode = value;
1288
1289 return 1;
1290 }
1291
tls_parse_stoc_server_name(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1292 int tls_parse_stoc_server_name(SSL *s, PACKET *pkt, unsigned int context,
1293 X509 *x, size_t chainidx)
1294 {
1295 if (s->ext.hostname == NULL) {
1296 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1297 return 0;
1298 }
1299
1300 if (PACKET_remaining(pkt) > 0) {
1301 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1302 return 0;
1303 }
1304
1305 if (!s->hit) {
1306 if (s->session->ext.hostname != NULL) {
1307 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1308 return 0;
1309 }
1310 s->session->ext.hostname = OPENSSL_strdup(s->ext.hostname);
1311 if (s->session->ext.hostname == NULL) {
1312 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1313 return 0;
1314 }
1315 }
1316
1317 return 1;
1318 }
1319
tls_parse_stoc_ec_pt_formats(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1320 int tls_parse_stoc_ec_pt_formats(SSL *s, PACKET *pkt, unsigned int context,
1321 X509 *x, size_t chainidx)
1322 {
1323 size_t ecpointformats_len;
1324 PACKET ecptformatlist;
1325
1326 if (!PACKET_as_length_prefixed_1(pkt, &ecptformatlist)) {
1327 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1328 return 0;
1329 }
1330 if (!s->hit) {
1331 ecpointformats_len = PACKET_remaining(&ecptformatlist);
1332 if (ecpointformats_len == 0) {
1333 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
1334 return 0;
1335 }
1336
1337 s->ext.peer_ecpointformats_len = 0;
1338 OPENSSL_free(s->ext.peer_ecpointformats);
1339 s->ext.peer_ecpointformats = OPENSSL_malloc(ecpointformats_len);
1340 if (s->ext.peer_ecpointformats == NULL) {
1341 s->ext.peer_ecpointformats_len = 0;
1342 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1343 return 0;
1344 }
1345
1346 s->ext.peer_ecpointformats_len = ecpointformats_len;
1347
1348 if (!PACKET_copy_bytes(&ecptformatlist,
1349 s->ext.peer_ecpointformats,
1350 ecpointformats_len)) {
1351 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1352 return 0;
1353 }
1354 }
1355
1356 return 1;
1357 }
1358
tls_parse_stoc_session_ticket(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1359 int tls_parse_stoc_session_ticket(SSL *s, PACKET *pkt, unsigned int context,
1360 X509 *x, size_t chainidx)
1361 {
1362 if (s->ext.session_ticket_cb != NULL &&
1363 !s->ext.session_ticket_cb(s, PACKET_data(pkt),
1364 PACKET_remaining(pkt),
1365 s->ext.session_ticket_cb_arg)) {
1366 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_EXTENSION);
1367 return 0;
1368 }
1369
1370 if (!tls_use_ticket(s)) {
1371 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1372 return 0;
1373 }
1374 if (PACKET_remaining(pkt) > 0) {
1375 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1376 return 0;
1377 }
1378
1379 s->ext.ticket_expected = 1;
1380
1381 return 1;
1382 }
1383
1384 #ifndef OPENSSL_NO_OCSP
tls_parse_stoc_status_request(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1385 int tls_parse_stoc_status_request(SSL *s, PACKET *pkt, unsigned int context,
1386 X509 *x, size_t chainidx)
1387 {
1388 if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) {
1389 /* We ignore this if the server sends a CertificateRequest */
1390 return 1;
1391 }
1392
1393 /*
1394 * MUST only be sent if we've requested a status
1395 * request message. In TLS <= 1.2 it must also be empty.
1396 */
1397 if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) {
1398 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1399 return 0;
1400 }
1401 if (!SSL_IS_TLS13(s) && PACKET_remaining(pkt) > 0) {
1402 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1403 return 0;
1404 }
1405
1406 if (SSL_IS_TLS13(s)) {
1407 /* We only know how to handle this if it's for the first Certificate in
1408 * the chain. We ignore any other responses.
1409 */
1410 if (chainidx != 0)
1411 return 1;
1412
1413 /* SSLfatal() already called */
1414 return tls_process_cert_status_body(s, pkt);
1415 }
1416
1417 /* Set flag to expect CertificateStatus message */
1418 s->ext.status_expected = 1;
1419
1420 return 1;
1421 }
1422 #endif
1423
1424
1425 #ifndef OPENSSL_NO_CT
tls_parse_stoc_sct(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1426 int tls_parse_stoc_sct(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1427 size_t chainidx)
1428 {
1429 if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) {
1430 /* We ignore this if the server sends it in a CertificateRequest */
1431 return 1;
1432 }
1433
1434 /*
1435 * Only take it if we asked for it - i.e if there is no CT validation
1436 * callback set, then a custom extension MAY be processing it, so we
1437 * need to let control continue to flow to that.
1438 */
1439 if (s->ct_validation_callback != NULL) {
1440 size_t size = PACKET_remaining(pkt);
1441
1442 /* Simply copy it off for later processing */
1443 OPENSSL_free(s->ext.scts);
1444 s->ext.scts = NULL;
1445
1446 s->ext.scts_len = (uint16_t)size;
1447 if (size > 0) {
1448 s->ext.scts = OPENSSL_malloc(size);
1449 if (s->ext.scts == NULL) {
1450 s->ext.scts_len = 0;
1451 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
1452 return 0;
1453 }
1454 if (!PACKET_copy_bytes(pkt, s->ext.scts, size)) {
1455 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1456 return 0;
1457 }
1458 }
1459 } else {
1460 ENDPOINT role = (context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0
1461 ? ENDPOINT_CLIENT : ENDPOINT_BOTH;
1462
1463 /*
1464 * If we didn't ask for it then there must be a custom extension,
1465 * otherwise this is unsolicited.
1466 */
1467 if (custom_ext_find(&s->cert->custext, role,
1468 TLSEXT_TYPE_signed_certificate_timestamp,
1469 NULL) == NULL) {
1470 SSLfatal(s, TLS1_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1471 return 0;
1472 }
1473
1474 if (!custom_ext_parse(s, context,
1475 TLSEXT_TYPE_signed_certificate_timestamp,
1476 PACKET_data(pkt), PACKET_remaining(pkt),
1477 x, chainidx)) {
1478 /* SSLfatal already called */
1479 return 0;
1480 }
1481 }
1482
1483 return 1;
1484 }
1485 #endif
1486
1487
1488 #ifndef OPENSSL_NO_NEXTPROTONEG
1489 /*
1490 * ssl_next_proto_validate validates a Next Protocol Negotiation block. No
1491 * elements of zero length are allowed and the set of elements must exactly
1492 * fill the length of the block. Returns 1 on success or 0 on failure.
1493 */
ssl_next_proto_validate(SSL * s,PACKET * pkt)1494 static int ssl_next_proto_validate(SSL *s, PACKET *pkt)
1495 {
1496 PACKET tmp_protocol;
1497
1498 while (PACKET_remaining(pkt)) {
1499 if (!PACKET_get_length_prefixed_1(pkt, &tmp_protocol)
1500 || PACKET_remaining(&tmp_protocol) == 0) {
1501 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1502 return 0;
1503 }
1504 }
1505
1506 return 1;
1507 }
1508
tls_parse_stoc_npn(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1509 int tls_parse_stoc_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1510 size_t chainidx)
1511 {
1512 unsigned char *selected;
1513 unsigned char selected_len;
1514 PACKET tmppkt;
1515
1516 /* Check if we are in a renegotiation. If so ignore this extension */
1517 if (!SSL_IS_FIRST_HANDSHAKE(s))
1518 return 1;
1519
1520 /* We must have requested it. */
1521 if (s->ctx->ext.npn_select_cb == NULL) {
1522 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1523 return 0;
1524 }
1525
1526 /* The data must be valid */
1527 tmppkt = *pkt;
1528 if (!ssl_next_proto_validate(s, &tmppkt)) {
1529 /* SSLfatal() already called */
1530 return 0;
1531 }
1532 if (s->ctx->ext.npn_select_cb(s, &selected, &selected_len,
1533 PACKET_data(pkt),
1534 PACKET_remaining(pkt),
1535 s->ctx->ext.npn_select_cb_arg) !=
1536 SSL_TLSEXT_ERR_OK) {
1537 SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_EXTENSION);
1538 return 0;
1539 }
1540
1541 /*
1542 * Could be non-NULL if server has sent multiple NPN extensions in
1543 * a single Serverhello
1544 */
1545 OPENSSL_free(s->ext.npn);
1546 s->ext.npn = OPENSSL_malloc(selected_len);
1547 if (s->ext.npn == NULL) {
1548 s->ext.npn_len = 0;
1549 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1550 return 0;
1551 }
1552
1553 memcpy(s->ext.npn, selected, selected_len);
1554 s->ext.npn_len = selected_len;
1555 s->s3.npn_seen = 1;
1556
1557 return 1;
1558 }
1559 #endif
1560
tls_parse_stoc_alpn(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1561 int tls_parse_stoc_alpn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1562 size_t chainidx)
1563 {
1564 size_t len;
1565
1566 /* We must have requested it. */
1567 if (!s->s3.alpn_sent) {
1568 SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1569 return 0;
1570 }
1571 /*-
1572 * The extension data consists of:
1573 * uint16 list_length
1574 * uint8 proto_length;
1575 * uint8 proto[proto_length];
1576 */
1577 if (!PACKET_get_net_2_len(pkt, &len)
1578 || PACKET_remaining(pkt) != len || !PACKET_get_1_len(pkt, &len)
1579 || PACKET_remaining(pkt) != len) {
1580 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1581 return 0;
1582 }
1583 OPENSSL_free(s->s3.alpn_selected);
1584 s->s3.alpn_selected = OPENSSL_malloc(len);
1585 if (s->s3.alpn_selected == NULL) {
1586 s->s3.alpn_selected_len = 0;
1587 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1588 return 0;
1589 }
1590 if (!PACKET_copy_bytes(pkt, s->s3.alpn_selected, len)) {
1591 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1592 return 0;
1593 }
1594 s->s3.alpn_selected_len = len;
1595
1596 if (s->session->ext.alpn_selected == NULL
1597 || s->session->ext.alpn_selected_len != len
1598 || memcmp(s->session->ext.alpn_selected, s->s3.alpn_selected, len)
1599 != 0) {
1600 /* ALPN not consistent with the old session so cannot use early_data */
1601 s->ext.early_data_ok = 0;
1602 }
1603 if (!s->hit) {
1604 /*
1605 * This is a new session and so alpn_selected should have been
1606 * initialised to NULL. We should update it with the selected ALPN.
1607 */
1608 if (!ossl_assert(s->session->ext.alpn_selected == NULL)) {
1609 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1610 return 0;
1611 }
1612 s->session->ext.alpn_selected =
1613 OPENSSL_memdup(s->s3.alpn_selected, s->s3.alpn_selected_len);
1614 if (s->session->ext.alpn_selected == NULL) {
1615 s->session->ext.alpn_selected_len = 0;
1616 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1617 return 0;
1618 }
1619 s->session->ext.alpn_selected_len = s->s3.alpn_selected_len;
1620 }
1621
1622 return 1;
1623 }
1624
1625 #ifndef OPENSSL_NO_SRTP
tls_parse_stoc_use_srtp(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1626 int tls_parse_stoc_use_srtp(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1627 size_t chainidx)
1628 {
1629 unsigned int id, ct, mki;
1630 int i;
1631 STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
1632 SRTP_PROTECTION_PROFILE *prof;
1633
1634 if (!PACKET_get_net_2(pkt, &ct) || ct != 2
1635 || !PACKET_get_net_2(pkt, &id)
1636 || !PACKET_get_1(pkt, &mki)
1637 || PACKET_remaining(pkt) != 0) {
1638 SSLfatal(s, SSL_AD_DECODE_ERROR,
1639 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
1640 return 0;
1641 }
1642
1643 if (mki != 0) {
1644 /* Must be no MKI, since we never offer one */
1645 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_SRTP_MKI_VALUE);
1646 return 0;
1647 }
1648
1649 /* Throw an error if the server gave us an unsolicited extension */
1650 clnt = SSL_get_srtp_profiles(s);
1651 if (clnt == NULL) {
1652 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_NO_SRTP_PROFILES);
1653 return 0;
1654 }
1655
1656 /*
1657 * Check to see if the server gave us something we support (and
1658 * presumably offered)
1659 */
1660 for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
1661 prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
1662
1663 if (prof->id == id) {
1664 s->srtp_profile = prof;
1665 return 1;
1666 }
1667 }
1668
1669 SSLfatal(s, SSL_AD_DECODE_ERROR,
1670 SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
1671 return 0;
1672 }
1673 #endif
1674
tls_parse_stoc_etm(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1675 int tls_parse_stoc_etm(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1676 size_t chainidx)
1677 {
1678 /* Ignore if inappropriate ciphersuite */
1679 if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
1680 && s->s3.tmp.new_cipher->algorithm_mac != SSL_AEAD
1681 && s->s3.tmp.new_cipher->algorithm_enc != SSL_RC4)
1682 s->ext.use_etm = 1;
1683
1684 return 1;
1685 }
1686
tls_parse_stoc_ems(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1687 int tls_parse_stoc_ems(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1688 size_t chainidx)
1689 {
1690 if (s->options & SSL_OP_NO_EXTENDED_MASTER_SECRET)
1691 return 1;
1692 s->s3.flags |= TLS1_FLAGS_RECEIVED_EXTMS;
1693 if (!s->hit)
1694 s->session->flags |= SSL_SESS_FLAG_EXTMS;
1695
1696 return 1;
1697 }
1698
tls_parse_stoc_supported_versions(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1699 int tls_parse_stoc_supported_versions(SSL *s, PACKET *pkt, unsigned int context,
1700 X509 *x, size_t chainidx)
1701 {
1702 unsigned int version;
1703
1704 if (!PACKET_get_net_2(pkt, &version)
1705 || PACKET_remaining(pkt) != 0) {
1706 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1707 return 0;
1708 }
1709
1710 /*
1711 * The only protocol version we support which is valid in this extension in
1712 * a ServerHello is TLSv1.3 therefore we shouldn't be getting anything else.
1713 */
1714 if (version != TLS1_3_VERSION) {
1715 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1716 SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
1717 return 0;
1718 }
1719
1720 /* We ignore this extension for HRRs except to sanity check it */
1721 if (context == SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST)
1722 return 1;
1723
1724 /* We just set it here. We validate it in ssl_choose_client_version */
1725 s->version = version;
1726
1727 return 1;
1728 }
1729
tls_parse_stoc_key_share(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1730 int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1731 size_t chainidx)
1732 {
1733 #ifndef OPENSSL_NO_TLS1_3
1734 unsigned int group_id;
1735 PACKET encoded_pt;
1736 EVP_PKEY *ckey = s->s3.tmp.pkey, *skey = NULL;
1737 const TLS_GROUP_INFO *ginf = NULL;
1738
1739 /* Sanity check */
1740 if (ckey == NULL || s->s3.peer_tmp != NULL) {
1741 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1742 return 0;
1743 }
1744
1745 if (!PACKET_get_net_2(pkt, &group_id)) {
1746 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1747 return 0;
1748 }
1749
1750 if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0) {
1751 const uint16_t *pgroups = NULL;
1752 size_t i, num_groups;
1753
1754 if (PACKET_remaining(pkt) != 0) {
1755 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1756 return 0;
1757 }
1758
1759 /*
1760 * It is an error if the HelloRetryRequest wants a key_share that we
1761 * already sent in the first ClientHello
1762 */
1763 if (group_id == s->s3.group_id) {
1764 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1765 return 0;
1766 }
1767
1768 /* Validate the selected group is one we support */
1769 tls1_get_supported_groups(s, &pgroups, &num_groups);
1770 for (i = 0; i < num_groups; i++) {
1771 if (group_id == pgroups[i])
1772 break;
1773 }
1774 if (i >= num_groups
1775 || !tls_group_allowed(s, group_id, SSL_SECOP_CURVE_SUPPORTED)) {
1776 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1777 return 0;
1778 }
1779
1780 s->s3.group_id = group_id;
1781 EVP_PKEY_free(s->s3.tmp.pkey);
1782 s->s3.tmp.pkey = NULL;
1783 return 1;
1784 }
1785
1786 if (group_id != s->s3.group_id) {
1787 /*
1788 * This isn't for the group that we sent in the original
1789 * key_share!
1790 */
1791 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1792 return 0;
1793 }
1794 /* Retain this group in the SSL_SESSION */
1795 if (!s->hit) {
1796 s->session->kex_group = group_id;
1797 } else if (group_id != s->session->kex_group) {
1798 /*
1799 * If this is a resumption but changed what group was used, we need
1800 * to record the new group in the session, but the session is not
1801 * a new session and could be in use by other threads. So, make
1802 * a copy of the session to record the new information so that it's
1803 * useful for any sessions resumed from tickets issued on this
1804 * connection.
1805 */
1806 SSL_SESSION *new_sess;
1807
1808 if ((new_sess = ssl_session_dup(s->session, 0)) == NULL) {
1809 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
1810 return 0;
1811 }
1812 SSL_SESSION_free(s->session);
1813 s->session = new_sess;
1814 s->session->kex_group = group_id;
1815 }
1816
1817 if ((ginf = tls1_group_id_lookup(s->ctx, group_id)) == NULL) {
1818 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1819 return 0;
1820 }
1821
1822 if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt)
1823 || PACKET_remaining(&encoded_pt) == 0) {
1824 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1825 return 0;
1826 }
1827
1828 if (!ginf->is_kem) {
1829 /* Regular KEX */
1830 skey = EVP_PKEY_new();
1831 if (skey == NULL || EVP_PKEY_copy_parameters(skey, ckey) <= 0) {
1832 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
1833 return 0;
1834 }
1835
1836 if (EVP_PKEY_set1_encoded_public_key(skey, PACKET_data(&encoded_pt),
1837 PACKET_remaining(&encoded_pt)) <= 0) {
1838 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_ECPOINT);
1839 EVP_PKEY_free(skey);
1840 return 0;
1841 }
1842
1843 if (ssl_derive(s, ckey, skey, 1) == 0) {
1844 /* SSLfatal() already called */
1845 EVP_PKEY_free(skey);
1846 return 0;
1847 }
1848 s->s3.peer_tmp = skey;
1849 } else {
1850 /* KEM Mode */
1851 const unsigned char *ct = PACKET_data(&encoded_pt);
1852 size_t ctlen = PACKET_remaining(&encoded_pt);
1853
1854 if (ssl_decapsulate(s, ckey, ct, ctlen, 1) == 0) {
1855 /* SSLfatal() already called */
1856 return 0;
1857 }
1858 }
1859 s->s3.did_kex = 1;
1860 #endif
1861
1862 return 1;
1863 }
1864
tls_parse_stoc_cookie(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1865 int tls_parse_stoc_cookie(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1866 size_t chainidx)
1867 {
1868 PACKET cookie;
1869
1870 if (!PACKET_as_length_prefixed_2(pkt, &cookie)
1871 || !PACKET_memdup(&cookie, &s->ext.tls13_cookie,
1872 &s->ext.tls13_cookie_len)) {
1873 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1874 return 0;
1875 }
1876
1877 return 1;
1878 }
1879
tls_parse_stoc_early_data(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1880 int tls_parse_stoc_early_data(SSL *s, PACKET *pkt, unsigned int context,
1881 X509 *x, size_t chainidx)
1882 {
1883 if (context == SSL_EXT_TLS1_3_NEW_SESSION_TICKET) {
1884 unsigned long max_early_data;
1885
1886 if (!PACKET_get_net_4(pkt, &max_early_data)
1887 || PACKET_remaining(pkt) != 0) {
1888 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_INVALID_MAX_EARLY_DATA);
1889 return 0;
1890 }
1891
1892 s->session->ext.max_early_data = max_early_data;
1893
1894 return 1;
1895 }
1896
1897 if (PACKET_remaining(pkt) != 0) {
1898 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1899 return 0;
1900 }
1901
1902 if (!s->ext.early_data_ok
1903 || !s->hit) {
1904 /*
1905 * If we get here then we didn't send early data, or we didn't resume
1906 * using the first identity, or the SNI/ALPN is not consistent so the
1907 * server should not be accepting it.
1908 */
1909 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_EXTENSION);
1910 return 0;
1911 }
1912
1913 s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
1914
1915 return 1;
1916 }
1917
tls_parse_stoc_psk(SSL * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1918 int tls_parse_stoc_psk(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
1919 size_t chainidx)
1920 {
1921 #ifndef OPENSSL_NO_TLS1_3
1922 unsigned int identity;
1923
1924 if (!PACKET_get_net_2(pkt, &identity) || PACKET_remaining(pkt) != 0) {
1925 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1926 return 0;
1927 }
1928
1929 if (identity >= (unsigned int)s->ext.tick_identity) {
1930 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_PSK_IDENTITY);
1931 return 0;
1932 }
1933
1934 /*
1935 * Session resumption tickets are always sent before PSK tickets. If the
1936 * ticket index is 0 then it must be for a session resumption ticket if we
1937 * sent two tickets, or if we didn't send a PSK ticket.
1938 */
1939 if (identity == 0 && (s->psksession == NULL || s->ext.tick_identity == 2)) {
1940 s->hit = 1;
1941 SSL_SESSION_free(s->psksession);
1942 s->psksession = NULL;
1943 return 1;
1944 }
1945
1946 if (s->psksession == NULL) {
1947 /* Should never happen */
1948 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1949 return 0;
1950 }
1951
1952 /*
1953 * If we used the external PSK for sending early_data then s->early_secret
1954 * is already set up, so don't overwrite it. Otherwise we copy the
1955 * early_secret across that we generated earlier.
1956 */
1957 if ((s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
1958 && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
1959 || s->session->ext.max_early_data > 0
1960 || s->psksession->ext.max_early_data == 0)
1961 memcpy(s->early_secret, s->psksession->early_secret, EVP_MAX_MD_SIZE);
1962
1963 SSL_SESSION_free(s->session);
1964 s->session = s->psksession;
1965 s->psksession = NULL;
1966 s->hit = 1;
1967 /* Early data is only allowed if we used the first ticket */
1968 if (identity != 0)
1969 s->ext.early_data_ok = 0;
1970 #endif
1971
1972 return 1;
1973 }
1974