xref: /freebsd/crypto/openssl/ssl/statem/extensions_clnt.c (revision f25b8c9fb4f58cf61adb47d7570abe7caa6d385d)
1 /*
2  * Copyright 2016-2025 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 "internal/ssl_unwrap.h"
14 #include "statem_local.h"
15 
tls_construct_ctos_renegotiate(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)16 EXT_RETURN tls_construct_ctos_renegotiate(SSL_CONNECTION *s, WPACKET *pkt,
17     unsigned int context, X509 *x,
18     size_t chainidx)
19 {
20     if (!s->renegotiate) {
21         /* If not renegotiating, send an empty RI extension to indicate support */
22 
23 #if DTLS_MAX_VERSION_INTERNAL != DTLS1_2_VERSION
24 #error Internal DTLS version error
25 #endif
26 
27         if (!SSL_CONNECTION_IS_DTLS(s)
28             && (s->min_proto_version >= TLS1_3_VERSION
29                 || (ssl_security(s, SSL_SECOP_VERSION, 0, TLS1_VERSION, NULL)
30                     && s->min_proto_version <= TLS1_VERSION))) {
31             /*
32              * For TLS <= 1.0 SCSV is used instead, and for TLS 1.3 this
33              * extension isn't used at all.
34              */
35             return EXT_RETURN_NOT_SENT;
36         }
37 
38         if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate)
39             || !WPACKET_start_sub_packet_u16(pkt)
40             || !WPACKET_put_bytes_u8(pkt, 0)
41             || !WPACKET_close(pkt)) {
42             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
43             return EXT_RETURN_FAIL;
44         }
45 
46         return EXT_RETURN_SENT;
47     }
48 
49     /* Add a complete RI extension if renegotiating */
50     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate)
51         || !WPACKET_start_sub_packet_u16(pkt)
52         || !WPACKET_sub_memcpy_u8(pkt, s->s3.previous_client_finished,
53             s->s3.previous_client_finished_len)
54         || !WPACKET_close(pkt)) {
55         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
56         return EXT_RETURN_FAIL;
57     }
58 
59     return EXT_RETURN_SENT;
60 }
61 
tls_construct_ctos_server_name(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)62 EXT_RETURN tls_construct_ctos_server_name(SSL_CONNECTION *s, WPACKET *pkt,
63     unsigned int context, X509 *x,
64     size_t chainidx)
65 {
66     if (s->ext.hostname == NULL)
67         return EXT_RETURN_NOT_SENT;
68 
69     /* Add TLS extension servername to the Client Hello message */
70     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_name)
71         /* Sub-packet for server_name extension */
72         || !WPACKET_start_sub_packet_u16(pkt)
73         /* Sub-packet for servername list (always 1 hostname)*/
74         || !WPACKET_start_sub_packet_u16(pkt)
75         || !WPACKET_put_bytes_u8(pkt, TLSEXT_NAMETYPE_host_name)
76         || !WPACKET_sub_memcpy_u16(pkt, s->ext.hostname,
77             strlen(s->ext.hostname))
78         || !WPACKET_close(pkt)
79         || !WPACKET_close(pkt)) {
80         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
81         return EXT_RETURN_FAIL;
82     }
83 
84     return EXT_RETURN_SENT;
85 }
86 
87 /* Push a Max Fragment Len extension into ClientHello */
tls_construct_ctos_maxfragmentlen(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)88 EXT_RETURN tls_construct_ctos_maxfragmentlen(SSL_CONNECTION *s, WPACKET *pkt,
89     unsigned int context, X509 *x,
90     size_t chainidx)
91 {
92     if (s->ext.max_fragment_len_mode == TLSEXT_max_fragment_length_DISABLED)
93         return EXT_RETURN_NOT_SENT;
94 
95     /* Add Max Fragment Length extension if client enabled it. */
96     /*-
97      * 4 bytes for this extension type and extension length
98      * 1 byte for the Max Fragment Length code value.
99      */
100     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_max_fragment_length)
101         /* Sub-packet for Max Fragment Length extension (1 byte) */
102         || !WPACKET_start_sub_packet_u16(pkt)
103         || !WPACKET_put_bytes_u8(pkt, s->ext.max_fragment_len_mode)
104         || !WPACKET_close(pkt)) {
105         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
106         return EXT_RETURN_FAIL;
107     }
108 
109     return EXT_RETURN_SENT;
110 }
111 
112 #ifndef OPENSSL_NO_SRP
tls_construct_ctos_srp(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)113 EXT_RETURN tls_construct_ctos_srp(SSL_CONNECTION *s, WPACKET *pkt,
114     unsigned int context,
115     X509 *x, size_t chainidx)
116 {
117     /* Add SRP username if there is one */
118     if (s->srp_ctx.login == NULL)
119         return EXT_RETURN_NOT_SENT;
120 
121     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_srp)
122         /* Sub-packet for SRP extension */
123         || !WPACKET_start_sub_packet_u16(pkt)
124         || !WPACKET_start_sub_packet_u8(pkt)
125         /* login must not be zero...internal error if so */
126         || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)
127         || !WPACKET_memcpy(pkt, s->srp_ctx.login,
128             strlen(s->srp_ctx.login))
129         || !WPACKET_close(pkt)
130         || !WPACKET_close(pkt)) {
131         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
132         return EXT_RETURN_FAIL;
133     }
134 
135     return EXT_RETURN_SENT;
136 }
137 #endif
138 
use_ecc(SSL_CONNECTION * s,int min_version,int max_version)139 static int use_ecc(SSL_CONNECTION *s, int min_version, int max_version)
140 {
141     int i, end, ret = 0;
142     unsigned long alg_k, alg_a;
143     STACK_OF(SSL_CIPHER) *cipher_stack = NULL;
144     const uint16_t *pgroups = NULL;
145     size_t num_groups, j;
146     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
147 
148     /* See if we support any ECC ciphersuites */
149     if (s->version == SSL3_VERSION)
150         return 0;
151 
152     cipher_stack = SSL_get1_supported_ciphers(ssl);
153     end = sk_SSL_CIPHER_num(cipher_stack);
154     for (i = 0; i < end; i++) {
155         const SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i);
156 
157         alg_k = c->algorithm_mkey;
158         alg_a = c->algorithm_auth;
159         if ((alg_k & (SSL_kECDHE | SSL_kECDHEPSK))
160             || (alg_a & SSL_aECDSA)
161             || c->min_tls >= TLS1_3_VERSION) {
162             ret = 1;
163             break;
164         }
165     }
166     sk_SSL_CIPHER_free(cipher_stack);
167     if (!ret)
168         return 0;
169 
170     /* Check we have at least one EC supported group */
171     tls1_get_supported_groups(s, &pgroups, &num_groups);
172     for (j = 0; j < num_groups; j++) {
173         uint16_t ctmp = pgroups[j];
174 
175         if (tls_valid_group(s, ctmp, min_version, max_version, 1, NULL)
176             && tls_group_allowed(s, ctmp, SSL_SECOP_CURVE_SUPPORTED))
177             return 1;
178     }
179 
180     return 0;
181 }
182 
tls_construct_ctos_ec_pt_formats(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)183 EXT_RETURN tls_construct_ctos_ec_pt_formats(SSL_CONNECTION *s, WPACKET *pkt,
184     unsigned int context, X509 *x,
185     size_t chainidx)
186 {
187     const unsigned char *pformats;
188     size_t num_formats;
189     int reason, min_version, max_version;
190 
191     reason = ssl_get_min_max_version(s, &min_version, &max_version, NULL);
192     if (reason != 0) {
193         SSLfatal(s, SSL_AD_INTERNAL_ERROR, reason);
194         return EXT_RETURN_FAIL;
195     }
196     if (!use_ecc(s, min_version, max_version))
197         return EXT_RETURN_NOT_SENT;
198 
199     /* Add TLS extension ECPointFormats to the ClientHello message */
200     tls1_get_formatlist(s, &pformats, &num_formats);
201 
202     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_ec_point_formats)
203         /* Sub-packet for formats extension */
204         || !WPACKET_start_sub_packet_u16(pkt)
205         || !WPACKET_sub_memcpy_u8(pkt, pformats, num_formats)
206         || !WPACKET_close(pkt)) {
207         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
208         return EXT_RETURN_FAIL;
209     }
210 
211     return EXT_RETURN_SENT;
212 }
213 
tls_construct_ctos_supported_groups(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)214 EXT_RETURN tls_construct_ctos_supported_groups(SSL_CONNECTION *s, WPACKET *pkt,
215     unsigned int context, X509 *x,
216     size_t chainidx)
217 {
218     const uint16_t *pgroups = NULL;
219     size_t num_groups = 0, i, tls13added = 0, added = 0;
220     int min_version, max_version, reason;
221 
222     reason = ssl_get_min_max_version(s, &min_version, &max_version, NULL);
223     if (reason != 0) {
224         SSLfatal(s, SSL_AD_INTERNAL_ERROR, reason);
225         return EXT_RETURN_FAIL;
226     }
227 
228     /*
229      * We only support EC groups in TLSv1.2 or below, and in DTLS. Therefore
230      * if we don't have EC support then we don't send this extension.
231      */
232     if (!use_ecc(s, min_version, max_version)
233         && (SSL_CONNECTION_IS_DTLS(s) || max_version < TLS1_3_VERSION))
234         return EXT_RETURN_NOT_SENT;
235 
236     /*
237      * Add TLS extension supported_groups to the ClientHello message
238      */
239     tls1_get_supported_groups(s, &pgroups, &num_groups);
240 
241     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_groups)
242         /* Sub-packet for supported_groups extension */
243         || !WPACKET_start_sub_packet_u16(pkt)
244         || !WPACKET_start_sub_packet_u16(pkt)
245         || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH)) {
246         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
247         return EXT_RETURN_FAIL;
248     }
249     /* Copy group ID if supported */
250     for (i = 0; i < num_groups; i++) {
251         uint16_t ctmp = pgroups[i];
252         int okfortls13;
253 
254         if (tls_valid_group(s, ctmp, min_version, max_version, 0, &okfortls13)
255             && tls_group_allowed(s, ctmp, SSL_SECOP_CURVE_SUPPORTED)) {
256             if (!WPACKET_put_bytes_u16(pkt, ctmp)) {
257                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
258                 return EXT_RETURN_FAIL;
259             }
260             if (okfortls13 && max_version == TLS1_3_VERSION)
261                 tls13added++;
262             added++;
263         }
264     }
265     if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
266         if (added == 0)
267             SSLfatal_data(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_GROUPS,
268                 "No groups enabled for max supported SSL/TLS version");
269         else
270             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
271         return EXT_RETURN_FAIL;
272     }
273 
274     if (tls13added == 0 && max_version == TLS1_3_VERSION) {
275         SSLfatal_data(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_GROUPS,
276             "No groups enabled for max supported SSL/TLS version");
277         return EXT_RETURN_FAIL;
278     }
279 
280     return EXT_RETURN_SENT;
281 }
282 
tls_construct_ctos_session_ticket(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)283 EXT_RETURN tls_construct_ctos_session_ticket(SSL_CONNECTION *s, WPACKET *pkt,
284     unsigned int context, X509 *x,
285     size_t chainidx)
286 {
287     size_t ticklen;
288 
289     if (!tls_use_ticket(s))
290         return EXT_RETURN_NOT_SENT;
291 
292     if (!s->new_session && s->session != NULL
293         && s->session->ext.tick != NULL
294         && s->session->ssl_version != TLS1_3_VERSION) {
295         ticklen = s->session->ext.ticklen;
296     } else if (s->session && s->ext.session_ticket != NULL
297         && s->ext.session_ticket->data != NULL) {
298         ticklen = s->ext.session_ticket->length;
299         s->session->ext.tick = OPENSSL_malloc(ticklen);
300         if (s->session->ext.tick == NULL) {
301             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
302             return EXT_RETURN_FAIL;
303         }
304         memcpy(s->session->ext.tick,
305             s->ext.session_ticket->data, ticklen);
306         s->session->ext.ticklen = ticklen;
307     } else {
308         ticklen = 0;
309     }
310 
311     if (ticklen == 0 && s->ext.session_ticket != NULL && s->ext.session_ticket->data == NULL)
312         return EXT_RETURN_NOT_SENT;
313 
314     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_session_ticket)
315         || !WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick, ticklen)) {
316         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
317         return EXT_RETURN_FAIL;
318     }
319 
320     return EXT_RETURN_SENT;
321 }
322 
tls_construct_ctos_sig_algs(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)323 EXT_RETURN tls_construct_ctos_sig_algs(SSL_CONNECTION *s, WPACKET *pkt,
324     unsigned int context, X509 *x,
325     size_t chainidx)
326 {
327     size_t salglen;
328     const uint16_t *salg;
329 
330     /*
331      * This used both in the initial hello and as part of renegotiation,
332      * in the latter case, the client version may be already set and may
333      * be lower than that initially offered in `client_version`.
334      */
335     if (!SSL_CONNECTION_IS_DTLS(s)) {
336         if (s->client_version < TLS1_2_VERSION
337             || (s->ssl.method->version != TLS_ANY_VERSION
338                 && s->version < TLS1_2_VERSION))
339             return EXT_RETURN_NOT_SENT;
340     } else {
341         if (DTLS_VERSION_LT(s->client_version, DTLS1_2_VERSION)
342             || (s->ssl.method->version != DTLS_ANY_VERSION
343                 && DTLS_VERSION_LT(s->version, DTLS1_2_VERSION)))
344             return EXT_RETURN_NOT_SENT;
345     }
346 
347     salglen = tls12_get_psigalgs(s, 1, &salg);
348     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signature_algorithms)
349         /* Sub-packet for sig-algs extension */
350         || !WPACKET_start_sub_packet_u16(pkt)
351         /* Sub-packet for the actual list */
352         || !WPACKET_start_sub_packet_u16(pkt)
353         || !tls12_copy_sigalgs(s, pkt, salg, salglen)
354         || !WPACKET_close(pkt)
355         || !WPACKET_close(pkt)) {
356         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
357         return EXT_RETURN_FAIL;
358     }
359 
360     return EXT_RETURN_SENT;
361 }
362 
363 #ifndef OPENSSL_NO_OCSP
tls_construct_ctos_status_request(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)364 EXT_RETURN tls_construct_ctos_status_request(SSL_CONNECTION *s, WPACKET *pkt,
365     unsigned int context, X509 *x,
366     size_t chainidx)
367 {
368     int i;
369 
370     /* This extension isn't defined for client Certificates */
371     if (x != NULL)
372         return EXT_RETURN_NOT_SENT;
373 
374     if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp)
375         return EXT_RETURN_NOT_SENT;
376 
377     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_status_request)
378         /* Sub-packet for status request extension */
379         || !WPACKET_start_sub_packet_u16(pkt)
380         || !WPACKET_put_bytes_u8(pkt, TLSEXT_STATUSTYPE_ocsp)
381         /* Sub-packet for the ids */
382         || !WPACKET_start_sub_packet_u16(pkt)) {
383         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
384         return EXT_RETURN_FAIL;
385     }
386     for (i = 0; i < sk_OCSP_RESPID_num(s->ext.ocsp.ids); i++) {
387         unsigned char *idbytes;
388         OCSP_RESPID *id = sk_OCSP_RESPID_value(s->ext.ocsp.ids, i);
389         int idlen = i2d_OCSP_RESPID(id, NULL);
390 
391         if (idlen <= 0
392             /* Sub-packet for an individual id */
393             || !WPACKET_sub_allocate_bytes_u16(pkt, idlen, &idbytes)
394             || i2d_OCSP_RESPID(id, &idbytes) != idlen) {
395             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
396             return EXT_RETURN_FAIL;
397         }
398     }
399     if (!WPACKET_close(pkt)
400         || !WPACKET_start_sub_packet_u16(pkt)) {
401         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
402         return EXT_RETURN_FAIL;
403     }
404     if (s->ext.ocsp.exts) {
405         unsigned char *extbytes;
406         int extlen = i2d_X509_EXTENSIONS(s->ext.ocsp.exts, NULL);
407 
408         if (extlen < 0) {
409             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
410             return EXT_RETURN_FAIL;
411         }
412         if (!WPACKET_allocate_bytes(pkt, extlen, &extbytes)
413             || i2d_X509_EXTENSIONS(s->ext.ocsp.exts, &extbytes)
414                 != extlen) {
415             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
416             return EXT_RETURN_FAIL;
417         }
418     }
419     if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
420         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
421         return EXT_RETURN_FAIL;
422     }
423 
424     return EXT_RETURN_SENT;
425 }
426 #endif
427 
428 #ifndef OPENSSL_NO_NEXTPROTONEG
tls_construct_ctos_npn(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)429 EXT_RETURN tls_construct_ctos_npn(SSL_CONNECTION *s, WPACKET *pkt,
430     unsigned int context,
431     X509 *x, size_t chainidx)
432 {
433     if (SSL_CONNECTION_GET_CTX(s)->ext.npn_select_cb == NULL
434         || !SSL_IS_FIRST_HANDSHAKE(s))
435         return EXT_RETURN_NOT_SENT;
436 
437     /*
438      * The client advertises an empty extension to indicate its support
439      * for Next Protocol Negotiation
440      */
441     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_next_proto_neg)
442         || !WPACKET_put_bytes_u16(pkt, 0)) {
443         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
444         return EXT_RETURN_FAIL;
445     }
446 
447     return EXT_RETURN_SENT;
448 }
449 #endif
450 
tls_construct_ctos_alpn(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)451 EXT_RETURN tls_construct_ctos_alpn(SSL_CONNECTION *s, WPACKET *pkt,
452     unsigned int context,
453     X509 *x, size_t chainidx)
454 {
455     s->s3.alpn_sent = 0;
456 
457     if (s->ext.alpn == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
458         return EXT_RETURN_NOT_SENT;
459 
460     if (!WPACKET_put_bytes_u16(pkt,
461             TLSEXT_TYPE_application_layer_protocol_negotiation)
462         /* Sub-packet ALPN extension */
463         || !WPACKET_start_sub_packet_u16(pkt)
464         || !WPACKET_sub_memcpy_u16(pkt, s->ext.alpn, s->ext.alpn_len)
465         || !WPACKET_close(pkt)) {
466         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
467         return EXT_RETURN_FAIL;
468     }
469     s->s3.alpn_sent = 1;
470 
471     return EXT_RETURN_SENT;
472 }
473 
474 #ifndef OPENSSL_NO_SRTP
tls_construct_ctos_use_srtp(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)475 EXT_RETURN tls_construct_ctos_use_srtp(SSL_CONNECTION *s, WPACKET *pkt,
476     unsigned int context, X509 *x,
477     size_t chainidx)
478 {
479     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
480     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = SSL_get_srtp_profiles(ssl);
481     int i, end;
482 
483     if (clnt == NULL)
484         return EXT_RETURN_NOT_SENT;
485 
486     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_use_srtp)
487         /* Sub-packet for SRTP extension */
488         || !WPACKET_start_sub_packet_u16(pkt)
489         /* Sub-packet for the protection profile list */
490         || !WPACKET_start_sub_packet_u16(pkt)) {
491         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
492         return EXT_RETURN_FAIL;
493     }
494 
495     end = sk_SRTP_PROTECTION_PROFILE_num(clnt);
496     for (i = 0; i < end; i++) {
497         const SRTP_PROTECTION_PROFILE *prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
498 
499         if (prof == NULL || !WPACKET_put_bytes_u16(pkt, prof->id)) {
500             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
501             return EXT_RETURN_FAIL;
502         }
503     }
504     if (!WPACKET_close(pkt)
505         /* Add an empty use_mki value */
506         || !WPACKET_put_bytes_u8(pkt, 0)
507         || !WPACKET_close(pkt)) {
508         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
509         return EXT_RETURN_FAIL;
510     }
511 
512     return EXT_RETURN_SENT;
513 }
514 #endif
515 
tls_construct_ctos_etm(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)516 EXT_RETURN tls_construct_ctos_etm(SSL_CONNECTION *s, WPACKET *pkt,
517     unsigned int context,
518     X509 *x, size_t chainidx)
519 {
520     if (s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
521         return EXT_RETURN_NOT_SENT;
522 
523     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_encrypt_then_mac)
524         || !WPACKET_put_bytes_u16(pkt, 0)) {
525         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
526         return EXT_RETURN_FAIL;
527     }
528 
529     return EXT_RETURN_SENT;
530 }
531 
532 #ifndef OPENSSL_NO_CT
tls_construct_ctos_sct(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)533 EXT_RETURN tls_construct_ctos_sct(SSL_CONNECTION *s, WPACKET *pkt,
534     unsigned int context,
535     X509 *x, size_t chainidx)
536 {
537     if (s->ct_validation_callback == NULL)
538         return EXT_RETURN_NOT_SENT;
539 
540     /* Not defined for client Certificates */
541     if (x != NULL)
542         return EXT_RETURN_NOT_SENT;
543 
544     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signed_certificate_timestamp)
545         || !WPACKET_put_bytes_u16(pkt, 0)) {
546         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
547         return EXT_RETURN_FAIL;
548     }
549 
550     return EXT_RETURN_SENT;
551 }
552 #endif
553 
tls_construct_ctos_ems(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)554 EXT_RETURN tls_construct_ctos_ems(SSL_CONNECTION *s, WPACKET *pkt,
555     unsigned int context,
556     X509 *x, size_t chainidx)
557 {
558     if (s->options & SSL_OP_NO_EXTENDED_MASTER_SECRET)
559         return EXT_RETURN_NOT_SENT;
560 
561     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_extended_master_secret)
562         || !WPACKET_put_bytes_u16(pkt, 0)) {
563         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
564         return EXT_RETURN_FAIL;
565     }
566 
567     return EXT_RETURN_SENT;
568 }
569 
tls_construct_ctos_supported_versions(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)570 EXT_RETURN tls_construct_ctos_supported_versions(SSL_CONNECTION *s, WPACKET *pkt,
571     unsigned int context, X509 *x,
572     size_t chainidx)
573 {
574     int currv, min_version, max_version, reason;
575 
576     reason = ssl_get_min_max_version(s, &min_version, &max_version, NULL);
577     if (reason != 0) {
578         SSLfatal(s, SSL_AD_INTERNAL_ERROR, reason);
579         return EXT_RETURN_FAIL;
580     }
581 
582     /*
583      * Don't include this if we can't negotiate TLSv1.3. We can do a straight
584      * comparison here because we will never be called in DTLS.
585      */
586     if (max_version < TLS1_3_VERSION)
587         return EXT_RETURN_NOT_SENT;
588 
589     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_versions)
590         || !WPACKET_start_sub_packet_u16(pkt)
591         || !WPACKET_start_sub_packet_u8(pkt)) {
592         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
593         return EXT_RETURN_FAIL;
594     }
595 
596     for (currv = max_version; currv >= min_version; currv--) {
597         if (!WPACKET_put_bytes_u16(pkt, currv)) {
598             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
599             return EXT_RETURN_FAIL;
600         }
601     }
602     if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
603         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
604         return EXT_RETURN_FAIL;
605     }
606 
607     return EXT_RETURN_SENT;
608 }
609 
610 /*
611  * Construct a psk_kex_modes extension.
612  */
tls_construct_ctos_psk_kex_modes(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)613 EXT_RETURN tls_construct_ctos_psk_kex_modes(SSL_CONNECTION *s, WPACKET *pkt,
614     unsigned int context, X509 *x,
615     size_t chainidx)
616 {
617 #ifndef OPENSSL_NO_TLS1_3
618     int nodhe = s->options & SSL_OP_ALLOW_NO_DHE_KEX;
619 
620     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk_kex_modes)
621         || !WPACKET_start_sub_packet_u16(pkt)
622         || !WPACKET_start_sub_packet_u8(pkt)
623         || !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE_DHE)
624         || (nodhe && !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE))
625         || !WPACKET_close(pkt)
626         || !WPACKET_close(pkt)) {
627         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
628         return EXT_RETURN_FAIL;
629     }
630 
631     s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_KE_DHE;
632     if (nodhe)
633         s->ext.psk_kex_mode |= TLSEXT_KEX_MODE_FLAG_KE;
634 #endif
635 
636     return EXT_RETURN_SENT;
637 }
638 
639 #ifndef OPENSSL_NO_TLS1_3
add_key_share(SSL_CONNECTION * s,WPACKET * pkt,unsigned int group_id,size_t loop_num)640 static int add_key_share(SSL_CONNECTION *s, WPACKET *pkt, unsigned int group_id, size_t loop_num)
641 {
642     unsigned char *encoded_pubkey = NULL;
643     EVP_PKEY *key_share_key = NULL;
644     size_t encodedlen;
645 
646     if (loop_num < s->s3.tmp.num_ks_pkey) {
647         if (!ossl_assert(s->hello_retry_request == SSL_HRR_PENDING)
648             || !ossl_assert(s->s3.tmp.ks_pkey[loop_num] != NULL)) {
649             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
650             return 0;
651         }
652         /*
653          * Could happen if we got an HRR that wasn't requesting a new key_share
654          */
655         key_share_key = s->s3.tmp.ks_pkey[loop_num];
656     } else {
657         key_share_key = ssl_generate_pkey_group(s, group_id);
658         if (key_share_key == NULL) {
659             /* SSLfatal() already called */
660             return 0;
661         }
662     }
663 
664     /* Encode the public key. */
665     encodedlen = EVP_PKEY_get1_encoded_public_key(key_share_key,
666         &encoded_pubkey);
667     if (encodedlen == 0) {
668         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EC_LIB);
669         goto err;
670     }
671 
672     /* Create KeyShareEntry */
673     if (!WPACKET_put_bytes_u16(pkt, group_id)
674         || !WPACKET_sub_memcpy_u16(pkt, encoded_pubkey, encodedlen)) {
675         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
676         goto err;
677     }
678 
679     /* For backward compatibility, we use the first valid group to add a key share */
680     if (loop_num == 0) {
681         s->s3.tmp.pkey = key_share_key;
682         s->s3.group_id = group_id;
683     }
684     /* We ensure in t1_lib.c that the loop number does not exceed OPENSSL_CLIENT_MAX_KEY_SHARES */
685     s->s3.tmp.ks_pkey[loop_num] = key_share_key;
686     s->s3.tmp.ks_group_id[loop_num] = group_id;
687     if (loop_num >= s->s3.tmp.num_ks_pkey)
688         s->s3.tmp.num_ks_pkey++;
689 
690     OPENSSL_free(encoded_pubkey);
691 
692     return 1;
693 err:
694     if (key_share_key != s->s3.tmp.ks_pkey[loop_num])
695         EVP_PKEY_free(key_share_key);
696     OPENSSL_free(encoded_pubkey);
697     return 0;
698 }
699 #endif
700 
tls_construct_ctos_key_share(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)701 EXT_RETURN tls_construct_ctos_key_share(SSL_CONNECTION *s, WPACKET *pkt,
702     unsigned int context, X509 *x,
703     size_t chainidx)
704 {
705 #ifndef OPENSSL_NO_TLS1_3
706     size_t i, num_groups = 0;
707     const uint16_t *pgroups = NULL;
708     uint16_t group_id = 0;
709     int add_only_one = 0;
710     size_t valid_keyshare = 0;
711 
712     /* key_share extension */
713     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_key_share)
714         /* Extension data sub-packet */
715         || !WPACKET_start_sub_packet_u16(pkt)
716         /* KeyShare list sub-packet */
717         || !WPACKET_start_sub_packet_u16(pkt)) {
718         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
719         return EXT_RETURN_FAIL;
720     }
721 
722     tls1_get_requested_keyshare_groups(s, &pgroups, &num_groups);
723     if (num_groups == 1 && pgroups[0] == 0) { /* Indication that no * prefix was used */
724         tls1_get_supported_groups(s, &pgroups, &num_groups);
725         add_only_one = 1;
726     }
727 
728     /* If neither the default nor the keyshares have any entry --> fatal */
729     if (num_groups == 0) {
730         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_KEY_SHARE);
731         return EXT_RETURN_FAIL;
732     }
733 
734     /* Add key shares */
735 
736     if (s->s3.group_id != 0 && s->s3.tmp.pkey == NULL) {
737         /* new, single key share */
738         group_id = s->s3.group_id;
739         s->s3.tmp.num_ks_pkey = 0;
740         if (!add_key_share(s, pkt, group_id, 0)) {
741             /* SSLfatal() already called */
742             return EXT_RETURN_FAIL;
743         }
744         valid_keyshare++;
745     } else {
746         if (s->ext.supportedgroups == NULL) /* use default */
747             add_only_one = 1;
748 
749         for (i = 0; i < num_groups; i++) {
750             if (!tls_group_allowed(s, pgroups[i], SSL_SECOP_CURVE_SUPPORTED))
751                 continue;
752             if (!tls_valid_group(s, pgroups[i], TLS1_3_VERSION, TLS1_3_VERSION,
753                     0, NULL))
754                 continue;
755 
756             group_id = pgroups[i];
757 
758             if (group_id == 0) {
759                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_KEY_SHARE);
760                 return EXT_RETURN_FAIL;
761             }
762             if (!add_key_share(s, pkt, group_id, valid_keyshare)) {
763                 /* SSLfatal() already called */
764                 return EXT_RETURN_FAIL;
765             }
766             valid_keyshare++;
767             if (add_only_one)
768                 break;
769         }
770     }
771 
772     if (valid_keyshare == 0) {
773         /* No key shares were allowed */
774         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_SUITABLE_KEY_SHARE);
775         return EXT_RETURN_FAIL;
776     }
777 
778     if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) {
779         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
780         return EXT_RETURN_FAIL;
781     }
782     return EXT_RETURN_SENT;
783 #else
784     return EXT_RETURN_NOT_SENT;
785 #endif
786 }
787 
tls_construct_ctos_cookie(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)788 EXT_RETURN tls_construct_ctos_cookie(SSL_CONNECTION *s, WPACKET *pkt,
789     unsigned int context,
790     X509 *x, size_t chainidx)
791 {
792     EXT_RETURN ret = EXT_RETURN_FAIL;
793 
794     /* Should only be set if we've had an HRR */
795     if (s->ext.tls13_cookie_len == 0)
796         return EXT_RETURN_NOT_SENT;
797 
798     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_cookie)
799         /* Extension data sub-packet */
800         || !WPACKET_start_sub_packet_u16(pkt)
801         || !WPACKET_sub_memcpy_u16(pkt, s->ext.tls13_cookie,
802             s->ext.tls13_cookie_len)
803         || !WPACKET_close(pkt)) {
804         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
805         goto end;
806     }
807 
808     ret = EXT_RETURN_SENT;
809 end:
810     OPENSSL_free(s->ext.tls13_cookie);
811     s->ext.tls13_cookie = NULL;
812     s->ext.tls13_cookie_len = 0;
813 
814     return ret;
815 }
816 
tls_construct_ctos_early_data(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)817 EXT_RETURN tls_construct_ctos_early_data(SSL_CONNECTION *s, WPACKET *pkt,
818     unsigned int context, X509 *x,
819     size_t chainidx)
820 {
821 #ifndef OPENSSL_NO_PSK
822     char identity[PSK_MAX_IDENTITY_LEN + 1];
823 #endif /* OPENSSL_NO_PSK */
824     const unsigned char *id = NULL;
825     size_t idlen = 0;
826     SSL_SESSION *psksess = NULL;
827     SSL_SESSION *edsess = NULL;
828     const EVP_MD *handmd = NULL;
829     SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s);
830 
831     if (s->hello_retry_request == SSL_HRR_PENDING)
832         handmd = ssl_handshake_md(s);
833 
834     if (s->psk_use_session_cb != NULL
835         && (!s->psk_use_session_cb(ussl, handmd, &id, &idlen, &psksess)
836             || (psksess != NULL
837                 && psksess->ssl_version != TLS1_3_VERSION))) {
838         SSL_SESSION_free(psksess);
839         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
840         return EXT_RETURN_FAIL;
841     }
842 
843 #ifndef OPENSSL_NO_PSK
844     if (psksess == NULL && s->psk_client_callback != NULL) {
845         unsigned char psk[PSK_MAX_PSK_LEN];
846         size_t psklen = 0;
847 
848         memset(identity, 0, sizeof(identity));
849         psklen = s->psk_client_callback(ussl, NULL,
850             identity, sizeof(identity) - 1,
851             psk, sizeof(psk));
852 
853         if (psklen > PSK_MAX_PSK_LEN) {
854             SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, ERR_R_INTERNAL_ERROR);
855             return EXT_RETURN_FAIL;
856         } else if (psklen > 0) {
857             const unsigned char tls13_aes128gcmsha256_id[] = { 0x13, 0x01 };
858             const SSL_CIPHER *cipher;
859 
860             idlen = strlen(identity);
861             if (idlen > PSK_MAX_IDENTITY_LEN) {
862                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
863                 return EXT_RETURN_FAIL;
864             }
865             id = (unsigned char *)identity;
866 
867             /*
868              * We found a PSK using an old style callback. We don't know
869              * the digest so we default to SHA256 as per the TLSv1.3 spec
870              */
871             cipher = SSL_CIPHER_find(SSL_CONNECTION_GET_SSL(s),
872                 tls13_aes128gcmsha256_id);
873             if (cipher == NULL) {
874                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
875                 return EXT_RETURN_FAIL;
876             }
877 
878             psksess = SSL_SESSION_new();
879             if (psksess == NULL
880                 || !SSL_SESSION_set1_master_key(psksess, psk, psklen)
881                 || !SSL_SESSION_set_cipher(psksess, cipher)
882                 || !SSL_SESSION_set_protocol_version(psksess, TLS1_3_VERSION)) {
883                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
884                 OPENSSL_cleanse(psk, psklen);
885                 return EXT_RETURN_FAIL;
886             }
887             OPENSSL_cleanse(psk, psklen);
888         }
889     }
890 #endif /* OPENSSL_NO_PSK */
891 
892     SSL_SESSION_free(s->psksession);
893     s->psksession = psksess;
894     if (psksess != NULL) {
895         OPENSSL_free(s->psksession_id);
896         s->psksession_id = OPENSSL_memdup(id, idlen);
897         if (s->psksession_id == NULL) {
898             s->psksession_id_len = 0;
899             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
900             return EXT_RETURN_FAIL;
901         }
902         s->psksession_id_len = idlen;
903     }
904 
905     if (s->early_data_state != SSL_EARLY_DATA_CONNECTING
906         || (s->session->ext.max_early_data == 0
907             && (psksess == NULL || psksess->ext.max_early_data == 0))) {
908         s->max_early_data = 0;
909         return EXT_RETURN_NOT_SENT;
910     }
911     edsess = s->session->ext.max_early_data != 0 ? s->session : psksess;
912     s->max_early_data = edsess->ext.max_early_data;
913 
914     if (edsess->ext.hostname != NULL) {
915         if (s->ext.hostname == NULL
916             || (s->ext.hostname != NULL
917                 && strcmp(s->ext.hostname, edsess->ext.hostname) != 0)) {
918             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
919                 SSL_R_INCONSISTENT_EARLY_DATA_SNI);
920             return EXT_RETURN_FAIL;
921         }
922     }
923 
924     if ((s->ext.alpn == NULL && edsess->ext.alpn_selected != NULL)) {
925         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
926         return EXT_RETURN_FAIL;
927     }
928 
929     /*
930      * Verify that we are offering an ALPN protocol consistent with the early
931      * data.
932      */
933     if (edsess->ext.alpn_selected != NULL) {
934         PACKET prots, alpnpkt;
935         int found = 0;
936 
937         if (!PACKET_buf_init(&prots, s->ext.alpn, s->ext.alpn_len)) {
938             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
939             return EXT_RETURN_FAIL;
940         }
941         while (PACKET_get_length_prefixed_1(&prots, &alpnpkt)) {
942             if (PACKET_equal(&alpnpkt, edsess->ext.alpn_selected,
943                     edsess->ext.alpn_selected_len)) {
944                 found = 1;
945                 break;
946             }
947         }
948         if (!found) {
949             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
950                 SSL_R_INCONSISTENT_EARLY_DATA_ALPN);
951             return EXT_RETURN_FAIL;
952         }
953     }
954 
955     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_early_data)
956         || !WPACKET_start_sub_packet_u16(pkt)
957         || !WPACKET_close(pkt)) {
958         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
959         return EXT_RETURN_FAIL;
960     }
961 
962     /*
963      * We set this to rejected here. Later, if the server acknowledges the
964      * extension, we set it to accepted.
965      */
966     s->ext.early_data = SSL_EARLY_DATA_REJECTED;
967     s->ext.early_data_ok = 1;
968 
969     return EXT_RETURN_SENT;
970 }
971 
972 #define F5_WORKAROUND_MIN_MSG_LEN 0xff
973 #define F5_WORKAROUND_MAX_MSG_LEN 0x200
974 
975 /*
976  * PSK pre binder overhead =
977  *  2 bytes for TLSEXT_TYPE_psk
978  *  2 bytes for extension length
979  *  2 bytes for identities list length
980  *  2 bytes for identity length
981  *  4 bytes for obfuscated_ticket_age
982  *  2 bytes for binder list length
983  *  1 byte for binder length
984  * The above excludes the number of bytes for the identity itself and the
985  * subsequent binder bytes
986  */
987 #define PSK_PRE_BINDER_OVERHEAD (2 + 2 + 2 + 2 + 4 + 2 + 1)
988 
tls_construct_ctos_padding(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)989 EXT_RETURN tls_construct_ctos_padding(SSL_CONNECTION *s, WPACKET *pkt,
990     unsigned int context, X509 *x,
991     size_t chainidx)
992 {
993     unsigned char *padbytes;
994     size_t hlen;
995 
996     if ((s->options & SSL_OP_TLSEXT_PADDING) == 0)
997         return EXT_RETURN_NOT_SENT;
998 
999     /*
1000      * Add padding to workaround bugs in F5 terminators. See RFC7685.
1001      * This code calculates the length of all extensions added so far but
1002      * excludes the PSK extension (because that MUST be written last). Therefore
1003      * this extension MUST always appear second to last.
1004      */
1005     if (!WPACKET_get_total_written(pkt, &hlen)) {
1006         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1007         return EXT_RETURN_FAIL;
1008     }
1009 
1010     /*
1011      * If we're going to send a PSK then that will be written out after this
1012      * extension, so we need to calculate how long it is going to be.
1013      */
1014     if (s->session->ssl_version == TLS1_3_VERSION
1015         && s->session->ext.ticklen != 0
1016         && s->session->cipher != NULL) {
1017         const EVP_MD *md = ssl_md(SSL_CONNECTION_GET_CTX(s),
1018             s->session->cipher->algorithm2);
1019 
1020         if (md != NULL) {
1021             /*
1022              * Add the fixed PSK overhead, the identity length and the binder
1023              * length.
1024              */
1025             int md_size = EVP_MD_get_size(md);
1026 
1027             if (md_size <= 0)
1028                 return EXT_RETURN_FAIL;
1029             hlen += PSK_PRE_BINDER_OVERHEAD + s->session->ext.ticklen
1030                 + md_size;
1031         }
1032     }
1033 
1034     if (hlen > F5_WORKAROUND_MIN_MSG_LEN && hlen < F5_WORKAROUND_MAX_MSG_LEN) {
1035         /* Calculate the amount of padding we need to add */
1036         hlen = F5_WORKAROUND_MAX_MSG_LEN - hlen;
1037 
1038         /*
1039          * Take off the size of extension header itself (2 bytes for type and
1040          * 2 bytes for length bytes), but ensure that the extension is at least
1041          * 1 byte long so as not to have an empty extension last (WebSphere 7.x,
1042          * 8.x are intolerant of that condition)
1043          */
1044         if (hlen > 4)
1045             hlen -= 4;
1046         else
1047             hlen = 1;
1048 
1049         if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_padding)
1050             || !WPACKET_sub_allocate_bytes_u16(pkt, hlen, &padbytes)) {
1051             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1052             return EXT_RETURN_FAIL;
1053         }
1054         memset(padbytes, 0, hlen);
1055     }
1056 
1057     return EXT_RETURN_SENT;
1058 }
1059 
1060 /*
1061  * Construct the pre_shared_key extension
1062  */
tls_construct_ctos_psk(SSL_CONNECTION * s,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1063 EXT_RETURN tls_construct_ctos_psk(SSL_CONNECTION *s, WPACKET *pkt,
1064     unsigned int context,
1065     X509 *x, size_t chainidx)
1066 {
1067 #ifndef OPENSSL_NO_TLS1_3
1068     uint32_t agesec, agems = 0;
1069     size_t binderoffset, msglen;
1070     int reshashsize = 0, pskhashsize = 0;
1071     unsigned char *resbinder = NULL, *pskbinder = NULL, *msgstart = NULL;
1072     const EVP_MD *handmd = NULL, *mdres = NULL, *mdpsk = NULL;
1073     int dores = 0;
1074     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
1075     OSSL_TIME t;
1076 
1077     s->ext.tick_identity = 0;
1078 
1079     /*
1080      * Note: At this stage of the code we only support adding a single
1081      * resumption PSK. If we add support for multiple PSKs then the length
1082      * calculations in the padding extension will need to be adjusted.
1083      */
1084 
1085     /*
1086      * If this is an incompatible or new session then we have nothing to resume
1087      * so don't add this extension.
1088      */
1089     if (s->session->ssl_version != TLS1_3_VERSION
1090         || (s->session->ext.ticklen == 0 && s->psksession == NULL))
1091         return EXT_RETURN_NOT_SENT;
1092 
1093     if (s->hello_retry_request == SSL_HRR_PENDING)
1094         handmd = ssl_handshake_md(s);
1095 
1096     if (s->session->ext.ticklen != 0) {
1097         /* Get the digest associated with the ciphersuite in the session */
1098         if (s->session->cipher == NULL) {
1099             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1100             return EXT_RETURN_FAIL;
1101         }
1102         mdres = ssl_md(sctx, s->session->cipher->algorithm2);
1103         if (mdres == NULL) {
1104             /*
1105              * Don't recognize this cipher so we can't use the session.
1106              * Ignore it
1107              */
1108             goto dopsksess;
1109         }
1110 
1111         if (s->hello_retry_request == SSL_HRR_PENDING && mdres != handmd) {
1112             /*
1113              * Selected ciphersuite hash does not match the hash for the session
1114              * so we can't use it.
1115              */
1116             goto dopsksess;
1117         }
1118 
1119         /*
1120          * Technically the C standard just says time() returns a time_t and says
1121          * nothing about the encoding of that type. In practice most
1122          * implementations follow POSIX which holds it as an integral type in
1123          * seconds since epoch. We've already made the assumption that we can do
1124          * this in multiple places in the code, so portability shouldn't be an
1125          * issue.
1126          */
1127         t = ossl_time_subtract(ossl_time_now(), s->session->time);
1128         agesec = (uint32_t)ossl_time2seconds(t);
1129         /*
1130          * We calculate the age in seconds but the server may work in ms. Due to
1131          * rounding errors we could overestimate the age by up to 1s. It is
1132          * better to underestimate it. Otherwise, if the RTT is very short, when
1133          * the server calculates the age reported by the client it could be
1134          * bigger than the age calculated on the server - which should never
1135          * happen.
1136          */
1137         if (agesec > 0)
1138             agesec--;
1139 
1140         if (s->session->ext.tick_lifetime_hint < agesec) {
1141             /* Ticket is too old. Ignore it. */
1142             goto dopsksess;
1143         }
1144 
1145         /*
1146          * Calculate age in ms. We're just doing it to nearest second. Should be
1147          * good enough.
1148          */
1149         agems = agesec * (uint32_t)1000;
1150 
1151         if (agesec != 0 && agems / (uint32_t)1000 != agesec) {
1152             /*
1153              * Overflow. Shouldn't happen unless this is a *really* old session.
1154              * If so we just ignore it.
1155              */
1156             goto dopsksess;
1157         }
1158 
1159         /*
1160          * Obfuscate the age. Overflow here is fine, this addition is supposed
1161          * to be mod 2^32.
1162          */
1163         agems += s->session->ext.tick_age_add;
1164 
1165         reshashsize = EVP_MD_get_size(mdres);
1166         if (reshashsize <= 0)
1167             goto dopsksess;
1168         s->ext.tick_identity++;
1169         dores = 1;
1170     }
1171 
1172 dopsksess:
1173     if (!dores && s->psksession == NULL)
1174         return EXT_RETURN_NOT_SENT;
1175 
1176     if (s->psksession != NULL) {
1177         mdpsk = ssl_md(sctx, s->psksession->cipher->algorithm2);
1178         if (mdpsk == NULL) {
1179             /*
1180              * Don't recognize this cipher so we can't use the session.
1181              * If this happens it's an application bug.
1182              */
1183             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1184             return EXT_RETURN_FAIL;
1185         }
1186 
1187         if (s->hello_retry_request == SSL_HRR_PENDING && mdpsk != handmd) {
1188             /*
1189              * Selected ciphersuite hash does not match the hash for the PSK
1190              * session. This is an application bug.
1191              */
1192             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1193             return EXT_RETURN_FAIL;
1194         }
1195 
1196         pskhashsize = EVP_MD_get_size(mdpsk);
1197         if (pskhashsize <= 0) {
1198             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
1199             return EXT_RETURN_FAIL;
1200         }
1201     }
1202 
1203     /* Create the extension, but skip over the binder for now */
1204     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk)
1205         || !WPACKET_start_sub_packet_u16(pkt)
1206         || !WPACKET_start_sub_packet_u16(pkt)) {
1207         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1208         return EXT_RETURN_FAIL;
1209     }
1210 
1211     if (dores) {
1212         if (!WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick,
1213                 s->session->ext.ticklen)
1214             || !WPACKET_put_bytes_u32(pkt, agems)) {
1215             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1216             return EXT_RETURN_FAIL;
1217         }
1218     }
1219 
1220     if (s->psksession != NULL) {
1221         if (!WPACKET_sub_memcpy_u16(pkt, s->psksession_id,
1222                 s->psksession_id_len)
1223             || !WPACKET_put_bytes_u32(pkt, 0)) {
1224             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1225             return EXT_RETURN_FAIL;
1226         }
1227         s->ext.tick_identity++;
1228     }
1229 
1230     if (!WPACKET_close(pkt)
1231         || !WPACKET_get_total_written(pkt, &binderoffset)
1232         || !WPACKET_start_sub_packet_u16(pkt)
1233         || (dores
1234             && !WPACKET_sub_allocate_bytes_u8(pkt, reshashsize, &resbinder))
1235         || (s->psksession != NULL
1236             && !WPACKET_sub_allocate_bytes_u8(pkt, pskhashsize, &pskbinder))
1237         || !WPACKET_close(pkt)
1238         || !WPACKET_close(pkt)
1239         || !WPACKET_get_total_written(pkt, &msglen)
1240         /*
1241          * We need to fill in all the sub-packet lengths now so we can
1242          * calculate the HMAC of the message up to the binders
1243          */
1244         || !WPACKET_fill_lengths(pkt)) {
1245         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1246         return EXT_RETURN_FAIL;
1247     }
1248 
1249     msgstart = WPACKET_get_curr(pkt) - msglen;
1250 
1251     if (dores
1252         && tls_psk_do_binder(s, mdres, msgstart, binderoffset, NULL,
1253                resbinder, s->session, 1, 0)
1254             != 1) {
1255         /* SSLfatal() already called */
1256         return EXT_RETURN_FAIL;
1257     }
1258 
1259     if (s->psksession != NULL
1260         && tls_psk_do_binder(s, mdpsk, msgstart, binderoffset, NULL,
1261                pskbinder, s->psksession, 1, 1)
1262             != 1) {
1263         /* SSLfatal() already called */
1264         return EXT_RETURN_FAIL;
1265     }
1266 
1267     return EXT_RETURN_SENT;
1268 #else
1269     return EXT_RETURN_NOT_SENT;
1270 #endif
1271 }
1272 
tls_construct_ctos_post_handshake_auth(SSL_CONNECTION * s,WPACKET * pkt,ossl_unused unsigned int context,ossl_unused X509 * x,ossl_unused size_t chainidx)1273 EXT_RETURN tls_construct_ctos_post_handshake_auth(SSL_CONNECTION *s, WPACKET *pkt,
1274     ossl_unused unsigned int context,
1275     ossl_unused X509 *x,
1276     ossl_unused size_t chainidx)
1277 {
1278 #ifndef OPENSSL_NO_TLS1_3
1279     if (!s->pha_enabled)
1280         return EXT_RETURN_NOT_SENT;
1281 
1282     /* construct extension - 0 length, no contents */
1283     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_post_handshake_auth)
1284         || !WPACKET_start_sub_packet_u16(pkt)
1285         || !WPACKET_close(pkt)) {
1286         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1287         return EXT_RETURN_FAIL;
1288     }
1289 
1290     s->post_handshake_auth = SSL_PHA_EXT_SENT;
1291 
1292     return EXT_RETURN_SENT;
1293 #else
1294     return EXT_RETURN_NOT_SENT;
1295 #endif
1296 }
1297 
1298 /*
1299  * Parse the server's renegotiation binding and abort if it's not right
1300  */
tls_parse_stoc_renegotiate(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1301 int tls_parse_stoc_renegotiate(SSL_CONNECTION *s, PACKET *pkt,
1302     unsigned int context,
1303     X509 *x, size_t chainidx)
1304 {
1305     size_t expected_len = s->s3.previous_client_finished_len
1306         + s->s3.previous_server_finished_len;
1307     size_t ilen;
1308     const unsigned char *data;
1309 
1310     /* Check for logic errors */
1311     if (!ossl_assert(expected_len == 0
1312             || s->s3.previous_client_finished_len != 0)
1313         || !ossl_assert(expected_len == 0
1314             || s->s3.previous_server_finished_len != 0)) {
1315         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1316         return 0;
1317     }
1318 
1319     /* Parse the length byte */
1320     if (!PACKET_get_1_len(pkt, &ilen)) {
1321         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR);
1322         return 0;
1323     }
1324 
1325     /* Consistency check */
1326     if (PACKET_remaining(pkt) != ilen) {
1327         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_RENEGOTIATION_ENCODING_ERR);
1328         return 0;
1329     }
1330 
1331     /* Check that the extension matches */
1332     if (ilen != expected_len) {
1333         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1334         return 0;
1335     }
1336 
1337     if (!PACKET_get_bytes(pkt, &data, s->s3.previous_client_finished_len)
1338         || memcmp(data, s->s3.previous_client_finished,
1339                s->s3.previous_client_finished_len)
1340             != 0) {
1341         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1342         return 0;
1343     }
1344 
1345     if (!PACKET_get_bytes(pkt, &data, s->s3.previous_server_finished_len)
1346         || memcmp(data, s->s3.previous_server_finished,
1347                s->s3.previous_server_finished_len)
1348             != 0) {
1349         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_RENEGOTIATION_MISMATCH);
1350         return 0;
1351     }
1352     s->s3.send_connection_binding = 1;
1353 
1354     return 1;
1355 }
1356 
1357 /* Parse the server's max fragment len extension packet */
tls_parse_stoc_maxfragmentlen(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1358 int tls_parse_stoc_maxfragmentlen(SSL_CONNECTION *s, PACKET *pkt,
1359     unsigned int context,
1360     X509 *x, size_t chainidx)
1361 {
1362     unsigned int value;
1363 
1364     if (PACKET_remaining(pkt) != 1 || !PACKET_get_1(pkt, &value)) {
1365         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1366         return 0;
1367     }
1368 
1369     /* |value| should contains a valid max-fragment-length code. */
1370     if (!IS_MAX_FRAGMENT_LENGTH_EXT_VALID(value)) {
1371         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1372             SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
1373         return 0;
1374     }
1375 
1376     /* Must be the same value as client-configured one who was sent to server */
1377     /*-
1378      * RFC 6066: if a client receives a maximum fragment length negotiation
1379      * response that differs from the length it requested, ...
1380      * It must abort with SSL_AD_ILLEGAL_PARAMETER alert
1381      */
1382     if (value != s->ext.max_fragment_len_mode) {
1383         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1384             SSL_R_SSL3_EXT_INVALID_MAX_FRAGMENT_LENGTH);
1385         return 0;
1386     }
1387 
1388     /*
1389      * Maximum Fragment Length Negotiation succeeded.
1390      * The negotiated Maximum Fragment Length is binding now.
1391      */
1392     s->session->ext.max_fragment_len_mode = value;
1393 
1394     return 1;
1395 }
1396 
tls_parse_stoc_server_name(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1397 int tls_parse_stoc_server_name(SSL_CONNECTION *s, PACKET *pkt,
1398     unsigned int context,
1399     X509 *x, size_t chainidx)
1400 {
1401     if (s->ext.hostname == NULL) {
1402         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1403         return 0;
1404     }
1405 
1406     if (PACKET_remaining(pkt) > 0) {
1407         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1408         return 0;
1409     }
1410 
1411     if (!s->hit) {
1412         if (s->session->ext.hostname != NULL) {
1413             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1414             return 0;
1415         }
1416         s->session->ext.hostname = OPENSSL_strdup(s->ext.hostname);
1417         if (s->session->ext.hostname == NULL) {
1418             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1419             return 0;
1420         }
1421     }
1422 
1423     return 1;
1424 }
1425 
tls_parse_stoc_ec_pt_formats(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1426 int tls_parse_stoc_ec_pt_formats(SSL_CONNECTION *s, PACKET *pkt,
1427     unsigned int context,
1428     X509 *x, size_t chainidx)
1429 {
1430     size_t ecpointformats_len;
1431     PACKET ecptformatlist;
1432 
1433     if (!PACKET_as_length_prefixed_1(pkt, &ecptformatlist)) {
1434         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1435         return 0;
1436     }
1437     if (!s->hit) {
1438         ecpointformats_len = PACKET_remaining(&ecptformatlist);
1439         if (ecpointformats_len == 0) {
1440             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_LENGTH);
1441             return 0;
1442         }
1443 
1444         s->ext.peer_ecpointformats_len = 0;
1445         OPENSSL_free(s->ext.peer_ecpointformats);
1446         s->ext.peer_ecpointformats = OPENSSL_malloc(ecpointformats_len);
1447         if (s->ext.peer_ecpointformats == NULL) {
1448             s->ext.peer_ecpointformats_len = 0;
1449             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1450             return 0;
1451         }
1452 
1453         s->ext.peer_ecpointformats_len = ecpointformats_len;
1454 
1455         if (!PACKET_copy_bytes(&ecptformatlist,
1456                 s->ext.peer_ecpointformats,
1457                 ecpointformats_len)) {
1458             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1459             return 0;
1460         }
1461     }
1462 
1463     return 1;
1464 }
1465 
tls_parse_stoc_session_ticket(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1466 int tls_parse_stoc_session_ticket(SSL_CONNECTION *s, PACKET *pkt,
1467     unsigned int context,
1468     X509 *x, size_t chainidx)
1469 {
1470     SSL *ssl = SSL_CONNECTION_GET_USER_SSL(s);
1471 
1472     if (s->ext.session_ticket_cb != NULL && !s->ext.session_ticket_cb(ssl, PACKET_data(pkt), PACKET_remaining(pkt), s->ext.session_ticket_cb_arg)) {
1473         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_EXTENSION);
1474         return 0;
1475     }
1476 
1477     if (!tls_use_ticket(s)) {
1478         SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1479         return 0;
1480     }
1481     if (PACKET_remaining(pkt) > 0) {
1482         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1483         return 0;
1484     }
1485 
1486     s->ext.ticket_expected = 1;
1487 
1488     return 1;
1489 }
1490 
1491 #ifndef OPENSSL_NO_OCSP
tls_parse_stoc_status_request(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1492 int tls_parse_stoc_status_request(SSL_CONNECTION *s, PACKET *pkt,
1493     unsigned int context,
1494     X509 *x, size_t chainidx)
1495 {
1496     if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) {
1497         /* We ignore this if the server sends a CertificateRequest */
1498         return 1;
1499     }
1500 
1501     /*
1502      * MUST only be sent if we've requested a status
1503      * request message. In TLS <= 1.2 it must also be empty.
1504      */
1505     if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) {
1506         SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1507         return 0;
1508     }
1509     if (!SSL_CONNECTION_IS_TLS13(s) && PACKET_remaining(pkt) > 0) {
1510         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1511         return 0;
1512     }
1513 
1514     if (SSL_CONNECTION_IS_TLS13(s)) {
1515         /* We only know how to handle this if it's for the first Certificate in
1516          * the chain. We ignore any other responses.
1517          */
1518         if (chainidx != 0)
1519             return 1;
1520 
1521         /* SSLfatal() already called */
1522         return tls_process_cert_status_body(s, pkt);
1523     }
1524 
1525     /* Set flag to expect CertificateStatus message */
1526     s->ext.status_expected = 1;
1527 
1528     return 1;
1529 }
1530 #endif
1531 
1532 #ifndef OPENSSL_NO_CT
tls_parse_stoc_sct(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1533 int tls_parse_stoc_sct(SSL_CONNECTION *s, PACKET *pkt, unsigned int context,
1534     X509 *x, size_t chainidx)
1535 {
1536     if (context == SSL_EXT_TLS1_3_CERTIFICATE_REQUEST) {
1537         /* We ignore this if the server sends it in a CertificateRequest */
1538         return 1;
1539     }
1540 
1541     /*
1542      * Only take it if we asked for it - i.e if there is no CT validation
1543      * callback set, then a custom extension MAY be processing it, so we
1544      * need to let control continue to flow to that.
1545      */
1546     if (s->ct_validation_callback != NULL) {
1547         size_t size = PACKET_remaining(pkt);
1548 
1549         /* Simply copy it off for later processing */
1550         OPENSSL_free(s->ext.scts);
1551         s->ext.scts = NULL;
1552 
1553         s->ext.scts_len = (uint16_t)size;
1554         if (size > 0) {
1555             s->ext.scts = OPENSSL_malloc(size);
1556             if (s->ext.scts == NULL) {
1557                 s->ext.scts_len = 0;
1558                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
1559                 return 0;
1560             }
1561             if (!PACKET_copy_bytes(pkt, s->ext.scts, size)) {
1562                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1563                 return 0;
1564             }
1565         }
1566     } else {
1567         ENDPOINT role = (context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0
1568             ? ENDPOINT_CLIENT
1569             : ENDPOINT_BOTH;
1570 
1571         /*
1572          * If we didn't ask for it then there must be a custom extension,
1573          * otherwise this is unsolicited.
1574          */
1575         if (custom_ext_find(&s->cert->custext, role,
1576                 TLSEXT_TYPE_signed_certificate_timestamp,
1577                 NULL)
1578             == NULL) {
1579             SSLfatal(s, TLS1_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1580             return 0;
1581         }
1582 
1583         if (!custom_ext_parse(s, context,
1584                 TLSEXT_TYPE_signed_certificate_timestamp,
1585                 PACKET_data(pkt), PACKET_remaining(pkt),
1586                 x, chainidx)) {
1587             /* SSLfatal already called */
1588             return 0;
1589         }
1590     }
1591 
1592     return 1;
1593 }
1594 #endif
1595 
1596 #ifndef OPENSSL_NO_NEXTPROTONEG
1597 /*
1598  * ssl_next_proto_validate validates a Next Protocol Negotiation block. No
1599  * elements of zero length are allowed and the set of elements must exactly
1600  * fill the length of the block. Returns 1 on success or 0 on failure.
1601  */
ssl_next_proto_validate(SSL_CONNECTION * s,PACKET * pkt)1602 static int ssl_next_proto_validate(SSL_CONNECTION *s, PACKET *pkt)
1603 {
1604     PACKET tmp_protocol;
1605 
1606     while (PACKET_remaining(pkt)) {
1607         if (!PACKET_get_length_prefixed_1(pkt, &tmp_protocol)
1608             || PACKET_remaining(&tmp_protocol) == 0) {
1609             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1610             return 0;
1611         }
1612     }
1613 
1614     return 1;
1615 }
1616 
tls_parse_stoc_npn(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1617 int tls_parse_stoc_npn(SSL_CONNECTION *s, PACKET *pkt, unsigned int context,
1618     X509 *x, size_t chainidx)
1619 {
1620     unsigned char *selected;
1621     unsigned char selected_len;
1622     PACKET tmppkt;
1623     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
1624 
1625     /* Check if we are in a renegotiation. If so ignore this extension */
1626     if (!SSL_IS_FIRST_HANDSHAKE(s))
1627         return 1;
1628 
1629     /* We must have requested it. */
1630     if (sctx->ext.npn_select_cb == NULL) {
1631         SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1632         return 0;
1633     }
1634 
1635     /* The data must be valid */
1636     tmppkt = *pkt;
1637     if (!ssl_next_proto_validate(s, &tmppkt)) {
1638         /* SSLfatal() already called */
1639         return 0;
1640     }
1641     if (sctx->ext.npn_select_cb(SSL_CONNECTION_GET_USER_SSL(s),
1642             &selected, &selected_len,
1643             PACKET_data(pkt), PACKET_remaining(pkt),
1644             sctx->ext.npn_select_cb_arg)
1645             != SSL_TLSEXT_ERR_OK
1646         || selected_len == 0) {
1647         SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_R_BAD_EXTENSION);
1648         return 0;
1649     }
1650 
1651     /*
1652      * Could be non-NULL if server has sent multiple NPN extensions in
1653      * a single Serverhello
1654      */
1655     OPENSSL_free(s->ext.npn);
1656     s->ext.npn = OPENSSL_malloc(selected_len);
1657     if (s->ext.npn == NULL) {
1658         s->ext.npn_len = 0;
1659         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1660         return 0;
1661     }
1662 
1663     memcpy(s->ext.npn, selected, selected_len);
1664     s->ext.npn_len = selected_len;
1665     s->s3.npn_seen = 1;
1666 
1667     return 1;
1668 }
1669 #endif
1670 
tls_parse_stoc_alpn(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1671 int tls_parse_stoc_alpn(SSL_CONNECTION *s, PACKET *pkt, unsigned int context,
1672     X509 *x, size_t chainidx)
1673 {
1674     size_t len;
1675     PACKET confpkt, protpkt;
1676     int valid = 0;
1677 
1678     /* We must have requested it. */
1679     if (!s->s3.alpn_sent) {
1680         SSLfatal(s, SSL_AD_UNSUPPORTED_EXTENSION, SSL_R_BAD_EXTENSION);
1681         return 0;
1682     }
1683     /*-
1684      * The extension data consists of:
1685      *   uint16 list_length
1686      *   uint8 proto_length;
1687      *   uint8 proto[proto_length];
1688      */
1689     if (!PACKET_get_net_2_len(pkt, &len)
1690         || PACKET_remaining(pkt) != len || !PACKET_get_1_len(pkt, &len)
1691         || PACKET_remaining(pkt) != len) {
1692         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1693         return 0;
1694     }
1695 
1696     /* It must be a protocol that we sent */
1697     if (!PACKET_buf_init(&confpkt, s->ext.alpn, s->ext.alpn_len)) {
1698         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1699         return 0;
1700     }
1701     while (PACKET_get_length_prefixed_1(&confpkt, &protpkt)) {
1702         if (PACKET_remaining(&protpkt) != len)
1703             continue;
1704         if (memcmp(PACKET_data(pkt), PACKET_data(&protpkt), len) == 0) {
1705             /* Valid protocol found */
1706             valid = 1;
1707             break;
1708         }
1709     }
1710 
1711     if (!valid) {
1712         /* The protocol sent from the server does not match one we advertised */
1713         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1714         return 0;
1715     }
1716 
1717     OPENSSL_free(s->s3.alpn_selected);
1718     s->s3.alpn_selected = OPENSSL_malloc(len);
1719     if (s->s3.alpn_selected == NULL) {
1720         s->s3.alpn_selected_len = 0;
1721         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1722         return 0;
1723     }
1724     if (!PACKET_copy_bytes(pkt, s->s3.alpn_selected, len)) {
1725         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
1726         return 0;
1727     }
1728     s->s3.alpn_selected_len = len;
1729 
1730     if (s->session->ext.alpn_selected == NULL
1731         || s->session->ext.alpn_selected_len != len
1732         || memcmp(s->session->ext.alpn_selected, s->s3.alpn_selected, len)
1733             != 0) {
1734         /* ALPN not consistent with the old session so cannot use early_data */
1735         s->ext.early_data_ok = 0;
1736     }
1737     if (!s->hit) {
1738         /*
1739          * This is a new session and so alpn_selected should have been
1740          * initialised to NULL. We should update it with the selected ALPN.
1741          */
1742         if (!ossl_assert(s->session->ext.alpn_selected == NULL)) {
1743             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1744             return 0;
1745         }
1746         s->session->ext.alpn_selected = OPENSSL_memdup(s->s3.alpn_selected, s->s3.alpn_selected_len);
1747         if (s->session->ext.alpn_selected == NULL) {
1748             s->session->ext.alpn_selected_len = 0;
1749             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1750             return 0;
1751         }
1752         s->session->ext.alpn_selected_len = s->s3.alpn_selected_len;
1753     }
1754 
1755     return 1;
1756 }
1757 
1758 #ifndef OPENSSL_NO_SRTP
tls_parse_stoc_use_srtp(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1759 int tls_parse_stoc_use_srtp(SSL_CONNECTION *s, PACKET *pkt,
1760     unsigned int context, X509 *x, size_t chainidx)
1761 {
1762     unsigned int id, ct, mki;
1763     int i;
1764     STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
1765     SRTP_PROTECTION_PROFILE *prof;
1766 
1767     if (!PACKET_get_net_2(pkt, &ct) || ct != 2
1768         || !PACKET_get_net_2(pkt, &id)
1769         || !PACKET_get_1(pkt, &mki)
1770         || PACKET_remaining(pkt) != 0) {
1771         SSLfatal(s, SSL_AD_DECODE_ERROR,
1772             SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
1773         return 0;
1774     }
1775 
1776     if (mki != 0) {
1777         /* Must be no MKI, since we never offer one */
1778         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_SRTP_MKI_VALUE);
1779         return 0;
1780     }
1781 
1782     /* Throw an error if the server gave us an unsolicited extension */
1783     clnt = SSL_get_srtp_profiles(SSL_CONNECTION_GET_SSL(s));
1784     if (clnt == NULL) {
1785         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_NO_SRTP_PROFILES);
1786         return 0;
1787     }
1788 
1789     /*
1790      * Check to see if the server gave us something we support (and
1791      * presumably offered)
1792      */
1793     for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
1794         prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
1795 
1796         if (prof->id == id) {
1797             s->srtp_profile = prof;
1798             return 1;
1799         }
1800     }
1801 
1802     SSLfatal(s, SSL_AD_DECODE_ERROR,
1803         SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
1804     return 0;
1805 }
1806 #endif
1807 
tls_parse_stoc_etm(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1808 int tls_parse_stoc_etm(SSL_CONNECTION *s, PACKET *pkt, unsigned int context,
1809     X509 *x, size_t chainidx)
1810 {
1811     /* Ignore if inappropriate ciphersuite */
1812     if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)
1813         && s->s3.tmp.new_cipher->algorithm_mac != SSL_AEAD
1814         && s->s3.tmp.new_cipher->algorithm_enc != SSL_RC4
1815         && s->s3.tmp.new_cipher->algorithm_enc != SSL_eGOST2814789CNT
1816         && s->s3.tmp.new_cipher->algorithm_enc != SSL_eGOST2814789CNT12
1817         && s->s3.tmp.new_cipher->algorithm_enc != SSL_MAGMA
1818         && s->s3.tmp.new_cipher->algorithm_enc != SSL_KUZNYECHIK)
1819         s->ext.use_etm = 1;
1820 
1821     return 1;
1822 }
1823 
tls_parse_stoc_ems(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1824 int tls_parse_stoc_ems(SSL_CONNECTION *s, PACKET *pkt, unsigned int context,
1825     X509 *x, size_t chainidx)
1826 {
1827     if (s->options & SSL_OP_NO_EXTENDED_MASTER_SECRET)
1828         return 1;
1829     s->s3.flags |= TLS1_FLAGS_RECEIVED_EXTMS;
1830     if (!s->hit)
1831         s->session->flags |= SSL_SESS_FLAG_EXTMS;
1832 
1833     return 1;
1834 }
1835 
tls_parse_stoc_supported_versions(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1836 int tls_parse_stoc_supported_versions(SSL_CONNECTION *s, PACKET *pkt,
1837     unsigned int context,
1838     X509 *x, size_t chainidx)
1839 {
1840     unsigned int version;
1841 
1842     if (!PACKET_get_net_2(pkt, &version)
1843         || PACKET_remaining(pkt) != 0) {
1844         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1845         return 0;
1846     }
1847 
1848     /*
1849      * The only protocol version we support which is valid in this extension in
1850      * a ServerHello is TLSv1.3 therefore we shouldn't be getting anything else.
1851      */
1852     if (version != TLS1_3_VERSION) {
1853         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
1854             SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
1855         return 0;
1856     }
1857 
1858     /* We ignore this extension for HRRs except to sanity check it */
1859     if (context == SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST)
1860         return 1;
1861 
1862     /* We just set it here. We validate it in ssl_choose_client_version */
1863     s->version = version;
1864     if (!ssl_set_record_protocol_version(s, version)) {
1865         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1866         return 0;
1867     }
1868 
1869     return 1;
1870 }
1871 
tls_parse_stoc_key_share(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)1872 int tls_parse_stoc_key_share(SSL_CONNECTION *s, PACKET *pkt,
1873     unsigned int context, X509 *x,
1874     size_t chainidx)
1875 {
1876 #ifndef OPENSSL_NO_TLS1_3
1877     unsigned int group_id;
1878     PACKET encoded_pt;
1879     EVP_PKEY *ckey = s->s3.tmp.pkey, *skey = NULL;
1880     const TLS_GROUP_INFO *ginf = NULL;
1881     uint16_t valid_ks_id = 0;
1882     size_t i;
1883 
1884     /* Sanity check */
1885     if (ckey == NULL || s->s3.peer_tmp != NULL) {
1886         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1887         return 0;
1888     }
1889 
1890     /* Which group ID does the server want -> group_id */
1891     if (!PACKET_get_net_2(pkt, &group_id)) {
1892         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1893         return 0;
1894     }
1895 
1896     if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0) {
1897         const uint16_t *pgroups = NULL;
1898         size_t num_groups;
1899 
1900         if (PACKET_remaining(pkt) != 0) {
1901             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
1902             return 0;
1903         }
1904 
1905         /*
1906          * It is an error if the HelloRetryRequest wants a key_share that we
1907          * already sent in the first ClientHello
1908          */
1909         for (i = 0; i < s->s3.tmp.num_ks_pkey; i++) {
1910             if (s->s3.tmp.ks_group_id[i] == group_id) {
1911                 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1912                 return 0;
1913             }
1914         }
1915 
1916         /* Validate the selected group is one we support */
1917         tls1_get_supported_groups(s, &pgroups, &num_groups);
1918         for (i = 0; i < num_groups; i++) {
1919             if (group_id == pgroups[i])
1920                 break;
1921         }
1922         if (i >= num_groups
1923             || !tls_group_allowed(s, group_id, SSL_SECOP_CURVE_SUPPORTED)
1924             || !tls_valid_group(s, group_id, TLS1_3_VERSION, TLS1_3_VERSION,
1925                 0, NULL)) {
1926             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1927             return 0;
1928         }
1929 
1930         /* Memorize which groupID the server wants */
1931         s->s3.group_id = group_id;
1932 
1933         /* The initial keyshares are obsolete now, hence free memory */
1934         for (i = 0; i < s->s3.tmp.num_ks_pkey; i++) {
1935             if (s->s3.tmp.ks_pkey[i] != NULL) {
1936                 EVP_PKEY_free(s->s3.tmp.ks_pkey[i]);
1937                 s->s3.tmp.ks_pkey[i] = NULL;
1938             }
1939         }
1940         s->s3.tmp.num_ks_pkey = 0;
1941         s->s3.tmp.pkey = NULL;
1942 
1943         return 1;
1944     }
1945 
1946     /*
1947      * check that the group requested by the server is one we've
1948      * sent a key share for, and if so: memorize which one
1949      */
1950     for (i = 0; i < s->s3.tmp.num_ks_pkey; i++) {
1951         if (s->s3.tmp.ks_group_id[i] == group_id) {
1952             valid_ks_id = group_id;
1953             ckey = s->s3.tmp.ks_pkey[i];
1954             s->s3.group_id = group_id;
1955             s->s3.tmp.pkey = ckey;
1956             break;
1957         }
1958     }
1959     if (valid_ks_id == 0) {
1960         /*
1961          * This isn't for the group that we sent in the original
1962          * key_share!
1963          */
1964         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1965         return 0;
1966     }
1967     /* Retain this group in the SSL_SESSION */
1968     if (!s->hit) {
1969         s->session->kex_group = group_id;
1970     } else if (group_id != s->session->kex_group) {
1971         /*
1972          * If this is a resumption but changed what group was used, we need
1973          * to record the new group in the session, but the session is not
1974          * a new session and could be in use by other threads.  So, make
1975          * a copy of the session to record the new information so that it's
1976          * useful for any sessions resumed from tickets issued on this
1977          * connection.
1978          */
1979         SSL_SESSION *new_sess;
1980 
1981         if ((new_sess = ssl_session_dup(s->session, 0)) == NULL) {
1982             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_SSL_LIB);
1983             return 0;
1984         }
1985         SSL_SESSION_free(s->session);
1986         s->session = new_sess;
1987         s->session->kex_group = group_id;
1988     }
1989 
1990     if ((ginf = tls1_group_id_lookup(SSL_CONNECTION_GET_CTX(s),
1991              group_id))
1992         == NULL) {
1993         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_KEY_SHARE);
1994         return 0;
1995     }
1996 
1997     if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt)
1998         || PACKET_remaining(&encoded_pt) == 0) {
1999         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2000         return 0;
2001     }
2002 
2003     if (!ginf->is_kem) {
2004         /* Regular KEX */
2005         skey = EVP_PKEY_new();
2006         if (skey == NULL || EVP_PKEY_copy_parameters(skey, ckey) <= 0) {
2007             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COPY_PARAMETERS_FAILED);
2008             EVP_PKEY_free(skey);
2009             return 0;
2010         }
2011 
2012         if (tls13_set_encoded_pub_key(skey, PACKET_data(&encoded_pt),
2013                 PACKET_remaining(&encoded_pt))
2014             <= 0) {
2015             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_ECPOINT);
2016             EVP_PKEY_free(skey);
2017             return 0;
2018         }
2019 
2020         if (ssl_derive(s, ckey, skey, 1) == 0) {
2021             /* SSLfatal() already called */
2022             EVP_PKEY_free(skey);
2023             return 0;
2024         }
2025         s->s3.peer_tmp = skey;
2026     } else {
2027         /* KEM Mode */
2028         const unsigned char *ct = PACKET_data(&encoded_pt);
2029         size_t ctlen = PACKET_remaining(&encoded_pt);
2030 
2031         if (ssl_decapsulate(s, ckey, ct, ctlen, 1) == 0) {
2032             /* SSLfatal() already called */
2033             return 0;
2034         }
2035     }
2036     s->s3.did_kex = 1;
2037 #endif
2038 
2039     return 1;
2040 }
2041 
tls_parse_stoc_cookie(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2042 int tls_parse_stoc_cookie(SSL_CONNECTION *s, PACKET *pkt, unsigned int context,
2043     X509 *x, size_t chainidx)
2044 {
2045     PACKET cookie;
2046 
2047     if (!PACKET_as_length_prefixed_2(pkt, &cookie)
2048         || !PACKET_memdup(&cookie, &s->ext.tls13_cookie,
2049             &s->ext.tls13_cookie_len)) {
2050         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2051         return 0;
2052     }
2053 
2054     return 1;
2055 }
2056 
tls_parse_stoc_early_data(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2057 int tls_parse_stoc_early_data(SSL_CONNECTION *s, PACKET *pkt,
2058     unsigned int context,
2059     X509 *x, size_t chainidx)
2060 {
2061     if (context == SSL_EXT_TLS1_3_NEW_SESSION_TICKET) {
2062         unsigned long max_early_data;
2063 
2064         if (!PACKET_get_net_4(pkt, &max_early_data)
2065             || PACKET_remaining(pkt) != 0) {
2066             SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_INVALID_MAX_EARLY_DATA);
2067             return 0;
2068         }
2069 
2070         s->session->ext.max_early_data = max_early_data;
2071 
2072         if (SSL_IS_QUIC_HANDSHAKE(s) && max_early_data != 0xffffffff) {
2073             /*
2074              * QUIC allows missing max_early_data, or a max_early_data value
2075              * of 0xffffffff. Missing max_early_data is stored in the session
2076              * as 0. This is indistinguishable in OpenSSL from a present
2077              * max_early_data value that was 0. In order that later checks for
2078              * invalid max_early_data correctly treat as an error the case where
2079              * max_early_data is present and it is 0, we store any invalid
2080              * value in the same (non-zero) way. Otherwise we would have to
2081              * introduce a new flag just for this.
2082              */
2083             s->session->ext.max_early_data = 1;
2084             SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_INVALID_MAX_EARLY_DATA);
2085             return 0;
2086         }
2087 
2088         return 1;
2089     }
2090 
2091     if (PACKET_remaining(pkt) != 0) {
2092         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2093         return 0;
2094     }
2095 
2096     if (!s->ext.early_data_ok
2097         || !s->hit) {
2098         /*
2099          * If we get here then we didn't send early data, or we didn't resume
2100          * using the first identity, or the SNI/ALPN is not consistent so the
2101          * server should not be accepting it.
2102          */
2103         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_EXTENSION);
2104         return 0;
2105     }
2106 
2107     s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
2108 
2109     return 1;
2110 }
2111 
tls_parse_stoc_psk(SSL_CONNECTION * s,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2112 int tls_parse_stoc_psk(SSL_CONNECTION *s, PACKET *pkt,
2113     unsigned int context, X509 *x,
2114     size_t chainidx)
2115 {
2116 #ifndef OPENSSL_NO_TLS1_3
2117     unsigned int identity;
2118 
2119     if (!PACKET_get_net_2(pkt, &identity) || PACKET_remaining(pkt) != 0) {
2120         SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_MISMATCH);
2121         return 0;
2122     }
2123 
2124     if (identity >= (unsigned int)s->ext.tick_identity) {
2125         SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_PSK_IDENTITY);
2126         return 0;
2127     }
2128 
2129     /*
2130      * Session resumption tickets are always sent before PSK tickets. If the
2131      * ticket index is 0 then it must be for a session resumption ticket if we
2132      * sent two tickets, or if we didn't send a PSK ticket.
2133      */
2134     if (identity == 0 && (s->psksession == NULL || s->ext.tick_identity == 2)) {
2135         s->hit = 1;
2136         SSL_SESSION_free(s->psksession);
2137         s->psksession = NULL;
2138         return 1;
2139     }
2140 
2141     if (s->psksession == NULL) {
2142         /* Should never happen */
2143         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2144         return 0;
2145     }
2146 
2147     /*
2148      * If we used the external PSK for sending early_data then s->early_secret
2149      * is already set up, so don't overwrite it. Otherwise we copy the
2150      * early_secret across that we generated earlier.
2151      */
2152     if ((s->early_data_state != SSL_EARLY_DATA_WRITE_RETRY
2153             && s->early_data_state != SSL_EARLY_DATA_FINISHED_WRITING)
2154         || s->session->ext.max_early_data > 0
2155         || s->psksession->ext.max_early_data == 0)
2156         memcpy(s->early_secret, s->psksession->early_secret, EVP_MAX_MD_SIZE);
2157 
2158     SSL_SESSION_free(s->session);
2159     s->session = s->psksession;
2160     s->psksession = NULL;
2161     s->hit = 1;
2162     /* Early data is only allowed if we used the first ticket */
2163     if (identity != 0)
2164         s->ext.early_data_ok = 0;
2165 #endif
2166 
2167     return 1;
2168 }
2169 
tls_construct_ctos_client_cert_type(SSL_CONNECTION * sc,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2170 EXT_RETURN tls_construct_ctos_client_cert_type(SSL_CONNECTION *sc, WPACKET *pkt,
2171     unsigned int context,
2172     X509 *x, size_t chainidx)
2173 {
2174     sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE;
2175     if (sc->client_cert_type == NULL)
2176         return EXT_RETURN_NOT_SENT;
2177 
2178     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_client_cert_type)
2179         || !WPACKET_start_sub_packet_u16(pkt)
2180         || !WPACKET_sub_memcpy_u8(pkt, sc->client_cert_type, sc->client_cert_type_len)
2181         || !WPACKET_close(pkt)) {
2182         SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2183         return EXT_RETURN_FAIL;
2184     }
2185     sc->ext.client_cert_type_ctos = OSSL_CERT_TYPE_CTOS_GOOD;
2186     return EXT_RETURN_SENT;
2187 }
2188 
tls_parse_stoc_client_cert_type(SSL_CONNECTION * sc,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2189 int tls_parse_stoc_client_cert_type(SSL_CONNECTION *sc, PACKET *pkt,
2190     unsigned int context,
2191     X509 *x, size_t chainidx)
2192 {
2193     unsigned int type;
2194 
2195     if (PACKET_remaining(pkt) != 1) {
2196         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2197         return 0;
2198     }
2199     if (!PACKET_get_1(pkt, &type)) {
2200         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2201         return 0;
2202     }
2203     /* We did not send/ask for this */
2204     if (!ossl_assert(sc->ext.client_cert_type_ctos == OSSL_CERT_TYPE_CTOS_GOOD)) {
2205         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2206         return 0;
2207     }
2208     /* We don't have this enabled */
2209     if (sc->client_cert_type == NULL) {
2210         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2211         return 0;
2212     }
2213     /* Given back a value we didn't configure */
2214     if (memchr(sc->client_cert_type, type, sc->client_cert_type_len) == NULL) {
2215         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_VALUE);
2216         return 0;
2217     }
2218     sc->ext.client_cert_type = type;
2219     return 1;
2220 }
2221 
tls_construct_ctos_server_cert_type(SSL_CONNECTION * sc,WPACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2222 EXT_RETURN tls_construct_ctos_server_cert_type(SSL_CONNECTION *sc, WPACKET *pkt,
2223     unsigned int context,
2224     X509 *x, size_t chainidx)
2225 {
2226     sc->ext.server_cert_type_ctos = OSSL_CERT_TYPE_CTOS_NONE;
2227     if (sc->server_cert_type == NULL)
2228         return EXT_RETURN_NOT_SENT;
2229 
2230     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_cert_type)
2231         || !WPACKET_start_sub_packet_u16(pkt)
2232         || !WPACKET_sub_memcpy_u8(pkt, sc->server_cert_type, sc->server_cert_type_len)
2233         || !WPACKET_close(pkt)) {
2234         SSLfatal(sc, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
2235         return EXT_RETURN_FAIL;
2236     }
2237     sc->ext.server_cert_type_ctos = OSSL_CERT_TYPE_CTOS_GOOD;
2238     return EXT_RETURN_SENT;
2239 }
2240 
tls_parse_stoc_server_cert_type(SSL_CONNECTION * sc,PACKET * pkt,unsigned int context,X509 * x,size_t chainidx)2241 int tls_parse_stoc_server_cert_type(SSL_CONNECTION *sc, PACKET *pkt,
2242     unsigned int context,
2243     X509 *x, size_t chainidx)
2244 {
2245     unsigned int type;
2246 
2247     if (PACKET_remaining(pkt) != 1) {
2248         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2249         return 0;
2250     }
2251     if (!PACKET_get_1(pkt, &type)) {
2252         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2253         return 0;
2254     }
2255     /* We did not send/ask for this */
2256     if (!ossl_assert(sc->ext.server_cert_type_ctos == OSSL_CERT_TYPE_CTOS_GOOD)) {
2257         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2258         return 0;
2259     }
2260     /* We don't have this enabled */
2261     if (sc->server_cert_type == NULL) {
2262         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION);
2263         return 0;
2264     }
2265     /* Given back a value we didn't configure */
2266     if (memchr(sc->server_cert_type, type, sc->server_cert_type_len) == NULL) {
2267         SSLfatal(sc, SSL_AD_DECODE_ERROR, SSL_R_BAD_VALUE);
2268         return 0;
2269     }
2270     sc->ext.server_cert_type = type;
2271     return 1;
2272 }
2273