Move s->packet and s->packet_length into s->rlayer
[openssl.git] / ssl / d1_srvr.c
1 /* ssl/d1_srvr.c */
2 /*
3  * DTLS implementation written by Nagendra Modadugu
4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
5  */
6 /* ====================================================================
7  * Copyright (c) 1999-2007 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    openssl-core@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
57  *
58  */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60  * All rights reserved.
61  *
62  * This package is an SSL implementation written
63  * by Eric Young (eay@cryptsoft.com).
64  * The implementation was written so as to conform with Netscapes SSL.
65  *
66  * This library is free for commercial and non-commercial use as long as
67  * the following conditions are aheared to.  The following conditions
68  * apply to all code found in this distribution, be it the RC4, RSA,
69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
70  * included with this distribution is covered by the same copyright terms
71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72  *
73  * Copyright remains Eric Young's, and as such any Copyright notices in
74  * the code are not to be removed.
75  * If this package is used in a product, Eric Young should be given attribution
76  * as the author of the parts of the library used.
77  * This can be in the form of a textual message at program startup or
78  * in documentation (online or textual) provided with the package.
79  *
80  * Redistribution and use in source and binary forms, with or without
81  * modification, are permitted provided that the following conditions
82  * are met:
83  * 1. Redistributions of source code must retain the copyright
84  *    notice, this list of conditions and the following disclaimer.
85  * 2. Redistributions in binary form must reproduce the above copyright
86  *    notice, this list of conditions and the following disclaimer in the
87  *    documentation and/or other materials provided with the distribution.
88  * 3. All advertising materials mentioning features or use of this software
89  *    must display the following acknowledgement:
90  *    "This product includes cryptographic software written by
91  *     Eric Young (eay@cryptsoft.com)"
92  *    The word 'cryptographic' can be left out if the rouines from the library
93  *    being used are not cryptographic related :-).
94  * 4. If you include any Windows specific code (or a derivative thereof) from
95  *    the apps directory (application code) you must include an acknowledgement:
96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97  *
98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108  * SUCH DAMAGE.
109  *
110  * The licence and distribution terms for any publically available version or
111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
112  * copied and put under another distribution licence
113  * [including the GNU Public Licence.]
114  */
115
116 #include <stdio.h>
117 #include "ssl_locl.h"
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120 #include <openssl/objects.h>
121 #include <openssl/evp.h>
122 #include <openssl/x509.h>
123 #include <openssl/md5.h>
124 #include <openssl/bn.h>
125 #ifndef OPENSSL_NO_DH
126 # include <openssl/dh.h>
127 #endif
128
129 static const SSL_METHOD *dtls1_get_server_method(int ver);
130 static int dtls1_send_hello_verify_request(SSL *s);
131
132 static const SSL_METHOD *dtls1_get_server_method(int ver)
133 {
134     if (ver == DTLS1_VERSION)
135         return (DTLSv1_server_method());
136     else if (ver == DTLS1_2_VERSION)
137         return (DTLSv1_2_server_method());
138     else
139         return (NULL);
140 }
141
142 IMPLEMENT_dtls1_meth_func(DTLS1_VERSION,
143                           DTLSv1_server_method,
144                           dtls1_accept,
145                           ssl_undefined_function,
146                           dtls1_get_server_method, DTLSv1_enc_data)
147
148     IMPLEMENT_dtls1_meth_func(DTLS1_2_VERSION,
149                           DTLSv1_2_server_method,
150                           dtls1_accept,
151                           ssl_undefined_function,
152                           dtls1_get_server_method, DTLSv1_2_enc_data)
153
154     IMPLEMENT_dtls1_meth_func(DTLS_ANY_VERSION,
155                           DTLS_server_method,
156                           dtls1_accept,
157                           ssl_undefined_function,
158                           dtls1_get_server_method, DTLSv1_2_enc_data)
159
160 int dtls1_accept(SSL *s)
161 {
162     BUF_MEM *buf;
163     unsigned long Time = (unsigned long)time(NULL);
164     void (*cb) (const SSL *ssl, int type, int val) = NULL;
165     unsigned long alg_k;
166     int ret = -1;
167     int new_state, state, skip = 0;
168     int listen;
169 #ifndef OPENSSL_NO_SCTP
170     unsigned char sctpauthkey[64];
171     char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
172 #endif
173
174     RAND_add(&Time, sizeof(Time), 0);
175     ERR_clear_error();
176     clear_sys_error();
177
178     if (s->info_callback != NULL)
179         cb = s->info_callback;
180     else if (s->ctx->info_callback != NULL)
181         cb = s->ctx->info_callback;
182
183     listen = s->d1->listen;
184
185     /* init things to blank */
186     s->in_handshake++;
187     if (!SSL_in_init(s) || SSL_in_before(s)) {
188         if(!SSL_clear(s))
189             return -1;
190     }
191
192     s->d1->listen = listen;
193 #ifndef OPENSSL_NO_SCTP
194     /*
195      * Notify SCTP BIO socket to enter handshake mode and prevent stream
196      * identifier other than 0. Will be ignored if no SCTP is used.
197      */
198     BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
199              s->in_handshake, NULL);
200 #endif
201
202 #ifndef OPENSSL_NO_HEARTBEATS
203     /*
204      * If we're awaiting a HeartbeatResponse, pretend we already got and
205      * don't await it anymore, because Heartbeats don't make sense during
206      * handshakes anyway.
207      */
208     if (s->tlsext_hb_pending) {
209         dtls1_stop_timer(s);
210         s->tlsext_hb_pending = 0;
211         s->tlsext_hb_seq++;
212     }
213 #endif
214
215     for (;;) {
216         state = s->state;
217
218         switch (s->state) {
219         case SSL_ST_RENEGOTIATE:
220             s->renegotiate = 1;
221             /* s->state=SSL_ST_ACCEPT; */
222
223         case SSL_ST_BEFORE:
224         case SSL_ST_ACCEPT:
225         case SSL_ST_BEFORE | SSL_ST_ACCEPT:
226         case SSL_ST_OK | SSL_ST_ACCEPT:
227
228             s->server = 1;
229             if (cb != NULL)
230                 cb(s, SSL_CB_HANDSHAKE_START, 1);
231
232             if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00)) {
233                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
234                 return -1;
235             }
236             s->type = SSL_ST_ACCEPT;
237
238             if (s->init_buf == NULL) {
239                 if ((buf = BUF_MEM_new()) == NULL) {
240                     ret = -1;
241                     goto end;
242                 }
243                 if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
244                     BUF_MEM_free(buf);
245                     ret = -1;
246                     goto end;
247                 }
248                 s->init_buf = buf;
249             }
250
251             if (!ssl3_setup_buffers(s)) {
252                 ret = -1;
253                 goto end;
254             }
255
256             s->init_num = 0;
257             s->d1->change_cipher_spec_ok = 0;
258             /*
259              * Should have been reset by ssl3_get_finished, too.
260              */
261             s->s3->change_cipher_spec = 0;
262
263             if (s->state != SSL_ST_RENEGOTIATE) {
264                 /*
265                  * Ok, we now need to push on a buffering BIO so that the
266                  * output is sent in a way that TCP likes :-) ...but not with
267                  * SCTP :-)
268                  */
269 #ifndef OPENSSL_NO_SCTP
270                 if (!BIO_dgram_is_sctp(SSL_get_wbio(s)))
271 #endif
272                     if (!ssl_init_wbio_buffer(s, 1)) {
273                         ret = -1;
274                         goto end;
275                     }
276
277                 ssl3_init_finished_mac(s);
278                 s->state = SSL3_ST_SR_CLNT_HELLO_A;
279                 s->ctx->stats.sess_accept++;
280             } else {
281                 /*
282                  * s->state == SSL_ST_RENEGOTIATE, we will just send a
283                  * HelloRequest
284                  */
285                 s->ctx->stats.sess_accept_renegotiate++;
286                 s->state = SSL3_ST_SW_HELLO_REQ_A;
287             }
288
289             break;
290
291         case SSL3_ST_SW_HELLO_REQ_A:
292         case SSL3_ST_SW_HELLO_REQ_B:
293
294             s->shutdown = 0;
295             dtls1_clear_record_buffer(s);
296             dtls1_start_timer(s);
297             ret = ssl3_send_hello_request(s);
298             if (ret <= 0)
299                 goto end;
300             s->s3->tmp.next_state = SSL3_ST_SR_CLNT_HELLO_A;
301             s->state = SSL3_ST_SW_FLUSH;
302             s->init_num = 0;
303
304             ssl3_init_finished_mac(s);
305             break;
306
307         case SSL3_ST_SW_HELLO_REQ_C:
308             s->state = SSL_ST_OK;
309             break;
310
311         case SSL3_ST_SR_CLNT_HELLO_A:
312         case SSL3_ST_SR_CLNT_HELLO_B:
313         case SSL3_ST_SR_CLNT_HELLO_C:
314
315             s->shutdown = 0;
316             ret = ssl3_get_client_hello(s);
317             if (ret <= 0)
318                 goto end;
319             dtls1_stop_timer(s);
320
321             if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
322                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
323             else
324                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
325
326             s->init_num = 0;
327
328             /*
329              * Reflect ClientHello sequence to remain stateless while
330              * listening
331              */
332             if (listen) {
333                 memcpy(s->s3->write_sequence, s->s3->read_sequence,
334                        sizeof(s->s3->write_sequence));
335             }
336
337             /* If we're just listening, stop here */
338             if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A) {
339                 ret = 2;
340                 s->d1->listen = 0;
341                 /*
342                  * Set expected sequence numbers to continue the handshake.
343                  */
344                 s->d1->handshake_read_seq = 2;
345                 s->d1->handshake_write_seq = 1;
346                 s->d1->next_handshake_write_seq = 1;
347                 goto end;
348             }
349
350             break;
351
352         case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
353         case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
354
355             ret = dtls1_send_hello_verify_request(s);
356             if (ret <= 0)
357                 goto end;
358             s->state = SSL3_ST_SW_FLUSH;
359             s->s3->tmp.next_state = SSL3_ST_SR_CLNT_HELLO_A;
360
361             /* HelloVerifyRequest resets Finished MAC */
362             if (s->version != DTLS1_BAD_VER)
363                 ssl3_init_finished_mac(s);
364             break;
365
366 #ifndef OPENSSL_NO_SCTP
367         case DTLS1_SCTP_ST_SR_READ_SOCK:
368
369             if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
370                 s->s3->in_read_app_data = 2;
371                 s->rwstate = SSL_READING;
372                 BIO_clear_retry_flags(SSL_get_rbio(s));
373                 BIO_set_retry_read(SSL_get_rbio(s));
374                 ret = -1;
375                 goto end;
376             }
377
378             s->state = SSL3_ST_SR_FINISHED_A;
379             break;
380
381         case DTLS1_SCTP_ST_SW_WRITE_SOCK:
382             ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
383             if (ret < 0)
384                 goto end;
385
386             if (ret == 0) {
387                 if (s->d1->next_state != SSL_ST_OK) {
388                     s->s3->in_read_app_data = 2;
389                     s->rwstate = SSL_READING;
390                     BIO_clear_retry_flags(SSL_get_rbio(s));
391                     BIO_set_retry_read(SSL_get_rbio(s));
392                     ret = -1;
393                     goto end;
394                 }
395             }
396
397             s->state = s->d1->next_state;
398             break;
399 #endif
400
401         case SSL3_ST_SW_SRVR_HELLO_A:
402         case SSL3_ST_SW_SRVR_HELLO_B:
403             s->renegotiate = 2;
404             dtls1_start_timer(s);
405             ret = ssl3_send_server_hello(s);
406             if (ret <= 0)
407                 goto end;
408
409             if (s->hit) {
410 #ifndef OPENSSL_NO_SCTP
411                 /*
412                  * Add new shared key for SCTP-Auth, will be ignored if no
413                  * SCTP used.
414                  */
415                 snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
416                          DTLS1_SCTP_AUTH_LABEL);
417
418                 SSL_export_keying_material(s, sctpauthkey,
419                                            sizeof(sctpauthkey), labelbuffer,
420                                            sizeof(labelbuffer), NULL, 0, 0);
421
422                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
423                          sizeof(sctpauthkey), sctpauthkey);
424 #endif
425 #ifndef OPENSSL_NO_TLSEXT
426                 if (s->tlsext_ticket_expected)
427                     s->state = SSL3_ST_SW_SESSION_TICKET_A;
428                 else
429                     s->state = SSL3_ST_SW_CHANGE_A;
430 #else
431                 s->state = SSL3_ST_SW_CHANGE_A;
432 #endif
433             } else
434                 s->state = SSL3_ST_SW_CERT_A;
435             s->init_num = 0;
436             break;
437
438         case SSL3_ST_SW_CERT_A:
439         case SSL3_ST_SW_CERT_B:
440             /* Check if it is anon DH or normal PSK */
441             if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
442                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
443                 dtls1_start_timer(s);
444                 ret = ssl3_send_server_certificate(s);
445                 if (ret <= 0)
446                     goto end;
447 #ifndef OPENSSL_NO_TLSEXT
448                 if (s->tlsext_status_expected)
449                     s->state = SSL3_ST_SW_CERT_STATUS_A;
450                 else
451                     s->state = SSL3_ST_SW_KEY_EXCH_A;
452             } else {
453                 skip = 1;
454                 s->state = SSL3_ST_SW_KEY_EXCH_A;
455             }
456 #else
457             } else
458                 skip = 1;
459
460             s->state = SSL3_ST_SW_KEY_EXCH_A;
461 #endif
462             s->init_num = 0;
463             break;
464
465         case SSL3_ST_SW_KEY_EXCH_A:
466         case SSL3_ST_SW_KEY_EXCH_B:
467             alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
468
469             /*
470              * clear this, it may get reset by
471              * send_server_key_exchange
472              */
473             s->s3->tmp.use_rsa_tmp = 0;
474
475             /*
476              * only send if a DH key exchange or RSA but we have a sign only
477              * certificate
478              */
479             if (0
480                 /*
481                  * PSK: send ServerKeyExchange if PSK identity hint if
482                  * provided
483                  */
484 #ifndef OPENSSL_NO_PSK
485                 || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
486 #endif
487                 || (alg_k & SSL_kDHE)
488                 || (alg_k & SSL_kECDHE)
489                 || ((alg_k & SSL_kRSA)
490                     && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
491                         || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
492                             && EVP_PKEY_size(s->cert->pkeys
493                                              [SSL_PKEY_RSA_ENC].privatekey) *
494                             8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
495                         )
496                     )
497                 )
498                 ) {
499                 dtls1_start_timer(s);
500                 ret = ssl3_send_server_key_exchange(s);
501                 if (ret <= 0)
502                     goto end;
503             } else
504                 skip = 1;
505
506             s->state = SSL3_ST_SW_CERT_REQ_A;
507             s->init_num = 0;
508             break;
509
510         case SSL3_ST_SW_CERT_REQ_A:
511         case SSL3_ST_SW_CERT_REQ_B:
512             if (                /* don't request cert unless asked for it: */
513                    !(s->verify_mode & SSL_VERIFY_PEER) ||
514                    /*
515                     * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
516                     * during re-negotiation:
517                     */
518                    ((s->session->peer != NULL) &&
519                     (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
520                    /*
521                     * never request cert in anonymous ciphersuites (see
522                     * section "Certificate request" in SSL 3 drafts and in
523                     * RFC 2246):
524                     */
525                    ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
526                     /*
527                      * ... except when the application insists on
528                      * verification (against the specs, but s3_clnt.c accepts
529                      * this for SSL 3)
530                      */
531                     !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
532                    /*
533                     * never request cert in Kerberos ciphersuites
534                     */
535                    (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
536                    /*
537                     * With normal PSK Certificates and Certificate Requests
538                     * are omitted
539                     */
540                    || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
541                 /* no cert request */
542                 skip = 1;
543                 s->s3->tmp.cert_request = 0;
544                 s->state = SSL3_ST_SW_SRVR_DONE_A;
545 #ifndef OPENSSL_NO_SCTP
546                 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
547                     s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
548                     s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
549                 }
550 #endif
551             } else {
552                 s->s3->tmp.cert_request = 1;
553                 dtls1_start_timer(s);
554                 ret = ssl3_send_certificate_request(s);
555                 if (ret <= 0)
556                     goto end;
557                 s->state = SSL3_ST_SW_SRVR_DONE_A;
558 # ifndef OPENSSL_NO_SCTP
559                 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
560                     s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
561                     s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
562                 }
563 # endif
564                 s->init_num = 0;
565             }
566             break;
567
568         case SSL3_ST_SW_SRVR_DONE_A:
569         case SSL3_ST_SW_SRVR_DONE_B:
570             dtls1_start_timer(s);
571             ret = ssl3_send_server_done(s);
572             if (ret <= 0)
573                 goto end;
574             s->s3->tmp.next_state = SSL3_ST_SR_CERT_A;
575             s->state = SSL3_ST_SW_FLUSH;
576             s->init_num = 0;
577             break;
578
579         case SSL3_ST_SW_FLUSH:
580             s->rwstate = SSL_WRITING;
581             if (BIO_flush(s->wbio) <= 0) {
582                 /*
583                  * If the write error was fatal, stop trying
584                  */
585                 if (!BIO_should_retry(s->wbio)) {
586                     s->rwstate = SSL_NOTHING;
587                     s->state = s->s3->tmp.next_state;
588                 }
589
590                 ret = -1;
591                 goto end;
592             }
593             s->rwstate = SSL_NOTHING;
594             s->state = s->s3->tmp.next_state;
595             break;
596
597         case SSL3_ST_SR_CERT_A:
598         case SSL3_ST_SR_CERT_B:
599             if (s->s3->tmp.cert_request) {
600                 ret = ssl3_get_client_certificate(s);
601                 if (ret <= 0)
602                     goto end;
603             }
604             s->init_num = 0;
605             s->state = SSL3_ST_SR_KEY_EXCH_A;
606             break;
607
608         case SSL3_ST_SR_KEY_EXCH_A:
609         case SSL3_ST_SR_KEY_EXCH_B:
610             ret = ssl3_get_client_key_exchange(s);
611             if (ret <= 0)
612                 goto end;
613 #ifndef OPENSSL_NO_SCTP
614             /*
615              * Add new shared key for SCTP-Auth, will be ignored if no SCTP
616              * used.
617              */
618             snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
619                      DTLS1_SCTP_AUTH_LABEL);
620
621             SSL_export_keying_material(s, sctpauthkey,
622                                        sizeof(sctpauthkey), labelbuffer,
623                                        sizeof(labelbuffer), NULL, 0, 0);
624
625             BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
626                      sizeof(sctpauthkey), sctpauthkey);
627 #endif
628
629             s->state = SSL3_ST_SR_CERT_VRFY_A;
630             s->init_num = 0;
631
632             if (ret == 2) {
633                 /*
634                  * For the ECDH ciphersuites when the client sends its ECDH
635                  * pub key in a certificate, the CertificateVerify message is
636                  * not sent.
637                  */
638                 s->state = SSL3_ST_SR_FINISHED_A;
639                 s->init_num = 0;
640             } else if (SSL_USE_SIGALGS(s)) {
641                 s->state = SSL3_ST_SR_CERT_VRFY_A;
642                 s->init_num = 0;
643                 if (!s->session->peer)
644                     break;
645                 if (!s->s3->handshake_buffer) {
646                     SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
647                     return -1;
648                 }
649                 /*
650                  * For sigalgs freeze the handshake buffer. If we support
651                  * extms we've done this already.
652                  */
653                 if (!(s->s3->flags & SSL_SESS_FLAG_EXTMS)) {
654                     s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
655                     if (!ssl3_digest_cached_records(s))
656                         return -1;
657                 }
658             } else {
659                 s->state = SSL3_ST_SR_CERT_VRFY_A;
660                 s->init_num = 0;
661
662                 /*
663                  * We need to get hashes here so if there is a client cert,
664                  * it can be verified
665                  */
666                 s->method->ssl3_enc->cert_verify_mac(s,
667                                                      NID_md5,
668                                                      &(s->s3->
669                                                        tmp.cert_verify_md
670                                                        [0]));
671                 s->method->ssl3_enc->cert_verify_mac(s, NID_sha1,
672                                                      &(s->s3->
673                                                        tmp.cert_verify_md
674                                                        [MD5_DIGEST_LENGTH]));
675             }
676             break;
677
678         case SSL3_ST_SR_CERT_VRFY_A:
679         case SSL3_ST_SR_CERT_VRFY_B:
680             /*
681              * This *should* be the first time we enable CCS, but be
682              * extra careful about surrounding code changes. We need
683              * to set this here because we don't know if we're
684              * expecting a CertificateVerify or not.
685              */
686             if (!s->s3->change_cipher_spec)
687                 s->d1->change_cipher_spec_ok = 1;
688             /* we should decide if we expected this one */
689             ret = ssl3_get_cert_verify(s);
690             if (ret <= 0)
691                 goto end;
692 #ifndef OPENSSL_NO_SCTP
693             if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
694                 state == SSL_ST_RENEGOTIATE)
695                 s->state = DTLS1_SCTP_ST_SR_READ_SOCK;
696             else
697 #endif
698                 s->state = SSL3_ST_SR_FINISHED_A;
699             s->init_num = 0;
700             break;
701
702         case SSL3_ST_SR_FINISHED_A:
703         case SSL3_ST_SR_FINISHED_B:
704             /*
705              * Enable CCS for resumed handshakes.
706              * In a full handshake, we end up here through
707              * SSL3_ST_SR_CERT_VRFY_B, so change_cipher_spec_ok was
708              * already set. Receiving a CCS clears the flag, so make
709              * sure not to re-enable it to ban duplicates.
710              * s->s3->change_cipher_spec is set when a CCS is
711              * processed in d1_pkt.c, and remains set until
712              * the client's Finished message is read.
713              */
714             if (!s->s3->change_cipher_spec)
715                 s->d1->change_cipher_spec_ok = 1;
716             ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A,
717                                     SSL3_ST_SR_FINISHED_B);
718             if (ret <= 0)
719                 goto end;
720             dtls1_stop_timer(s);
721             if (s->hit)
722                 s->state = SSL_ST_OK;
723 #ifndef OPENSSL_NO_TLSEXT
724             else if (s->tlsext_ticket_expected)
725                 s->state = SSL3_ST_SW_SESSION_TICKET_A;
726 #endif
727             else
728                 s->state = SSL3_ST_SW_CHANGE_A;
729             s->init_num = 0;
730             break;
731
732 #ifndef OPENSSL_NO_TLSEXT
733         case SSL3_ST_SW_SESSION_TICKET_A:
734         case SSL3_ST_SW_SESSION_TICKET_B:
735             ret = ssl3_send_newsession_ticket(s);
736             if (ret <= 0)
737                 goto end;
738             s->state = SSL3_ST_SW_CHANGE_A;
739             s->init_num = 0;
740             break;
741
742         case SSL3_ST_SW_CERT_STATUS_A:
743         case SSL3_ST_SW_CERT_STATUS_B:
744             ret = ssl3_send_cert_status(s);
745             if (ret <= 0)
746                 goto end;
747             s->state = SSL3_ST_SW_KEY_EXCH_A;
748             s->init_num = 0;
749             break;
750
751 #endif
752
753         case SSL3_ST_SW_CHANGE_A:
754         case SSL3_ST_SW_CHANGE_B:
755
756             s->session->cipher = s->s3->tmp.new_cipher;
757             if (!s->method->ssl3_enc->setup_key_block(s)) {
758                 ret = -1;
759                 goto end;
760             }
761
762             ret = dtls1_send_change_cipher_spec(s,
763                                                 SSL3_ST_SW_CHANGE_A,
764                                                 SSL3_ST_SW_CHANGE_B);
765
766             if (ret <= 0)
767                 goto end;
768
769 #ifndef OPENSSL_NO_SCTP
770             if (!s->hit) {
771                 /*
772                  * Change to new shared key of SCTP-Auth, will be ignored if
773                  * no SCTP used.
774                  */
775                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
776                          0, NULL);
777             }
778 #endif
779
780             s->state = SSL3_ST_SW_FINISHED_A;
781             s->init_num = 0;
782
783             if (!s->method->ssl3_enc->change_cipher_state(s,
784                                                           SSL3_CHANGE_CIPHER_SERVER_WRITE))
785             {
786                 ret = -1;
787                 goto end;
788             }
789
790             dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
791             break;
792
793         case SSL3_ST_SW_FINISHED_A:
794         case SSL3_ST_SW_FINISHED_B:
795             ret = ssl3_send_finished(s,
796                                      SSL3_ST_SW_FINISHED_A,
797                                      SSL3_ST_SW_FINISHED_B,
798                                      s->method->
799                                      ssl3_enc->server_finished_label,
800                                      s->method->
801                                      ssl3_enc->server_finished_label_len);
802             if (ret <= 0)
803                 goto end;
804             s->state = SSL3_ST_SW_FLUSH;
805             if (s->hit) {
806                 s->s3->tmp.next_state = SSL3_ST_SR_FINISHED_A;
807
808 #ifndef OPENSSL_NO_SCTP
809                 /*
810                  * Change to new shared key of SCTP-Auth, will be ignored if
811                  * no SCTP used.
812                  */
813                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
814                          0, NULL);
815 #endif
816             } else {
817                 s->s3->tmp.next_state = SSL_ST_OK;
818 #ifndef OPENSSL_NO_SCTP
819                 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
820                     s->d1->next_state = s->s3->tmp.next_state;
821                     s->s3->tmp.next_state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
822                 }
823 #endif
824             }
825             s->init_num = 0;
826             break;
827
828         case SSL_ST_OK:
829             /* clean a few things up */
830             ssl3_cleanup_key_block(s);
831
832             /* remove buffering on output */
833             ssl_free_wbio_buffer(s);
834
835             s->init_num = 0;
836
837             if (s->renegotiate == 2) { /* skipped if we just sent a
838                                         * HelloRequest */
839                 s->renegotiate = 0;
840                 s->new_session = 0;
841
842                 ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
843
844                 s->ctx->stats.sess_accept_good++;
845                 /* s->server=1; */
846                 s->handshake_func = dtls1_accept;
847
848                 if (cb != NULL)
849                     cb(s, SSL_CB_HANDSHAKE_DONE, 1);
850             }
851
852             ret = 1;
853
854             /* done handshaking, next message is client hello */
855             s->d1->handshake_read_seq = 0;
856             /* next message is server hello */
857             s->d1->handshake_write_seq = 0;
858             s->d1->next_handshake_write_seq = 0;
859             goto end;
860             /* break; */
861
862         default:
863             SSLerr(SSL_F_DTLS1_ACCEPT, SSL_R_UNKNOWN_STATE);
864             ret = -1;
865             goto end;
866             /* break; */
867         }
868
869         if (!s->s3->tmp.reuse_message && !skip) {
870             if (s->debug) {
871                 if ((ret = BIO_flush(s->wbio)) <= 0)
872                     goto end;
873             }
874
875             if ((cb != NULL) && (s->state != state)) {
876                 new_state = s->state;
877                 s->state = state;
878                 cb(s, SSL_CB_ACCEPT_LOOP, 1);
879                 s->state = new_state;
880             }
881         }
882         skip = 0;
883     }
884  end:
885     /* BIO_flush(s->wbio); */
886
887     s->in_handshake--;
888 #ifndef OPENSSL_NO_SCTP
889     /*
890      * Notify SCTP BIO socket to leave handshake mode and prevent stream
891      * identifier other than 0. Will be ignored if no SCTP is used.
892      */
893     BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
894              s->in_handshake, NULL);
895 #endif
896
897     if (cb != NULL)
898         cb(s, SSL_CB_ACCEPT_EXIT, ret);
899     return (ret);
900 }
901
902 int dtls1_send_hello_verify_request(SSL *s)
903 {
904     unsigned int msg_len;
905     unsigned char *msg, *buf, *p;
906
907     if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) {
908         buf = (unsigned char *)s->init_buf->data;
909
910         msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
911         /* Always use DTLS 1.0 version: see RFC 6347 */
912         *(p++) = DTLS1_VERSION >> 8;
913         *(p++) = DTLS1_VERSION & 0xFF;
914
915         if (s->ctx->app_gen_cookie_cb == NULL ||
916             s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
917                                       &(s->d1->cookie_len)) == 0) {
918             SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,
919                    ERR_R_INTERNAL_ERROR);
920             return 0;
921         }
922
923         *(p++) = (unsigned char)s->d1->cookie_len;
924         memcpy(p, s->d1->cookie, s->d1->cookie_len);
925         p += s->d1->cookie_len;
926         msg_len = p - msg;
927
928         dtls1_set_message_header(s, buf,
929                                  DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0,
930                                  msg_len);
931
932         s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
933         /* number of bytes to write */
934         s->init_num = p - buf;
935         s->init_off = 0;
936     }
937
938     /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
939     return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
940 }