Reorganise header files
[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                 DTLS_RECORD_LAYER_resync_write(&s->rlayer);
334             }
335
336             /* If we're just listening, stop here */
337             if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A) {
338                 ret = 2;
339                 s->d1->listen = 0;
340                 /*
341                  * Set expected sequence numbers to continue the handshake.
342                  */
343                 s->d1->handshake_read_seq = 2;
344                 s->d1->handshake_write_seq = 1;
345                 s->d1->next_handshake_write_seq = 1;
346                 goto end;
347             }
348
349             break;
350
351         case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
352         case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
353
354             ret = dtls1_send_hello_verify_request(s);
355             if (ret <= 0)
356                 goto end;
357             s->state = SSL3_ST_SW_FLUSH;
358             s->s3->tmp.next_state = SSL3_ST_SR_CLNT_HELLO_A;
359
360             /* HelloVerifyRequest resets Finished MAC */
361             if (s->version != DTLS1_BAD_VER)
362                 ssl3_init_finished_mac(s);
363             break;
364
365 #ifndef OPENSSL_NO_SCTP
366         case DTLS1_SCTP_ST_SR_READ_SOCK:
367
368             if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
369                 s->s3->in_read_app_data = 2;
370                 s->rwstate = SSL_READING;
371                 BIO_clear_retry_flags(SSL_get_rbio(s));
372                 BIO_set_retry_read(SSL_get_rbio(s));
373                 ret = -1;
374                 goto end;
375             }
376
377             s->state = SSL3_ST_SR_FINISHED_A;
378             break;
379
380         case DTLS1_SCTP_ST_SW_WRITE_SOCK:
381             ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
382             if (ret < 0)
383                 goto end;
384
385             if (ret == 0) {
386                 if (s->d1->next_state != SSL_ST_OK) {
387                     s->s3->in_read_app_data = 2;
388                     s->rwstate = SSL_READING;
389                     BIO_clear_retry_flags(SSL_get_rbio(s));
390                     BIO_set_retry_read(SSL_get_rbio(s));
391                     ret = -1;
392                     goto end;
393                 }
394             }
395
396             s->state = s->d1->next_state;
397             break;
398 #endif
399
400         case SSL3_ST_SW_SRVR_HELLO_A:
401         case SSL3_ST_SW_SRVR_HELLO_B:
402             s->renegotiate = 2;
403             dtls1_start_timer(s);
404             ret = ssl3_send_server_hello(s);
405             if (ret <= 0)
406                 goto end;
407
408             if (s->hit) {
409 #ifndef OPENSSL_NO_SCTP
410                 /*
411                  * Add new shared key for SCTP-Auth, will be ignored if no
412                  * SCTP used.
413                  */
414                 snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
415                          DTLS1_SCTP_AUTH_LABEL);
416
417                 SSL_export_keying_material(s, sctpauthkey,
418                                            sizeof(sctpauthkey), labelbuffer,
419                                            sizeof(labelbuffer), NULL, 0, 0);
420
421                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
422                          sizeof(sctpauthkey), sctpauthkey);
423 #endif
424 #ifndef OPENSSL_NO_TLSEXT
425                 if (s->tlsext_ticket_expected)
426                     s->state = SSL3_ST_SW_SESSION_TICKET_A;
427                 else
428                     s->state = SSL3_ST_SW_CHANGE_A;
429 #else
430                 s->state = SSL3_ST_SW_CHANGE_A;
431 #endif
432             } else
433                 s->state = SSL3_ST_SW_CERT_A;
434             s->init_num = 0;
435             break;
436
437         case SSL3_ST_SW_CERT_A:
438         case SSL3_ST_SW_CERT_B:
439             /* Check if it is anon DH or normal PSK */
440             if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
441                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
442                 dtls1_start_timer(s);
443                 ret = ssl3_send_server_certificate(s);
444                 if (ret <= 0)
445                     goto end;
446 #ifndef OPENSSL_NO_TLSEXT
447                 if (s->tlsext_status_expected)
448                     s->state = SSL3_ST_SW_CERT_STATUS_A;
449                 else
450                     s->state = SSL3_ST_SW_KEY_EXCH_A;
451             } else {
452                 skip = 1;
453                 s->state = SSL3_ST_SW_KEY_EXCH_A;
454             }
455 #else
456             } else
457                 skip = 1;
458
459             s->state = SSL3_ST_SW_KEY_EXCH_A;
460 #endif
461             s->init_num = 0;
462             break;
463
464         case SSL3_ST_SW_KEY_EXCH_A:
465         case SSL3_ST_SW_KEY_EXCH_B:
466             alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
467
468             /*
469              * clear this, it may get reset by
470              * send_server_key_exchange
471              */
472             s->s3->tmp.use_rsa_tmp = 0;
473
474             /*
475              * only send if a DH key exchange or RSA but we have a sign only
476              * certificate
477              */
478             if (0
479                 /*
480                  * PSK: send ServerKeyExchange if PSK identity hint if
481                  * provided
482                  */
483 #ifndef OPENSSL_NO_PSK
484                 || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
485 #endif
486                 || (alg_k & SSL_kDHE)
487                 || (alg_k & SSL_kECDHE)
488                 || ((alg_k & SSL_kRSA)
489                     && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
490                         || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
491                             && EVP_PKEY_size(s->cert->pkeys
492                                              [SSL_PKEY_RSA_ENC].privatekey) *
493                             8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
494                         )
495                     )
496                 )
497                 ) {
498                 dtls1_start_timer(s);
499                 ret = ssl3_send_server_key_exchange(s);
500                 if (ret <= 0)
501                     goto end;
502             } else
503                 skip = 1;
504
505             s->state = SSL3_ST_SW_CERT_REQ_A;
506             s->init_num = 0;
507             break;
508
509         case SSL3_ST_SW_CERT_REQ_A:
510         case SSL3_ST_SW_CERT_REQ_B:
511             if (                /* don't request cert unless asked for it: */
512                    !(s->verify_mode & SSL_VERIFY_PEER) ||
513                    /*
514                     * if SSL_VERIFY_CLIENT_ONCE is set, don't request cert
515                     * during re-negotiation:
516                     */
517                    ((s->session->peer != NULL) &&
518                     (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
519                    /*
520                     * never request cert in anonymous ciphersuites (see
521                     * section "Certificate request" in SSL 3 drafts and in
522                     * RFC 2246):
523                     */
524                    ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
525                     /*
526                      * ... except when the application insists on
527                      * verification (against the specs, but s3_clnt.c accepts
528                      * this for SSL 3)
529                      */
530                     !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
531                    /*
532                     * never request cert in Kerberos ciphersuites
533                     */
534                    (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
535                    /*
536                     * With normal PSK Certificates and Certificate Requests
537                     * are omitted
538                     */
539                    || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
540                 /* no cert request */
541                 skip = 1;
542                 s->s3->tmp.cert_request = 0;
543                 s->state = SSL3_ST_SW_SRVR_DONE_A;
544 #ifndef OPENSSL_NO_SCTP
545                 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
546                     s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
547                     s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
548                 }
549 #endif
550             } else {
551                 s->s3->tmp.cert_request = 1;
552                 dtls1_start_timer(s);
553                 ret = ssl3_send_certificate_request(s);
554                 if (ret <= 0)
555                     goto end;
556                 s->state = SSL3_ST_SW_SRVR_DONE_A;
557 # ifndef OPENSSL_NO_SCTP
558                 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
559                     s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
560                     s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
561                 }
562 # endif
563                 s->init_num = 0;
564             }
565             break;
566
567         case SSL3_ST_SW_SRVR_DONE_A:
568         case SSL3_ST_SW_SRVR_DONE_B:
569             dtls1_start_timer(s);
570             ret = ssl3_send_server_done(s);
571             if (ret <= 0)
572                 goto end;
573             s->s3->tmp.next_state = SSL3_ST_SR_CERT_A;
574             s->state = SSL3_ST_SW_FLUSH;
575             s->init_num = 0;
576             break;
577
578         case SSL3_ST_SW_FLUSH:
579             s->rwstate = SSL_WRITING;
580             if (BIO_flush(s->wbio) <= 0) {
581                 /*
582                  * If the write error was fatal, stop trying
583                  */
584                 if (!BIO_should_retry(s->wbio)) {
585                     s->rwstate = SSL_NOTHING;
586                     s->state = s->s3->tmp.next_state;
587                 }
588
589                 ret = -1;
590                 goto end;
591             }
592             s->rwstate = SSL_NOTHING;
593             s->state = s->s3->tmp.next_state;
594             break;
595
596         case SSL3_ST_SR_CERT_A:
597         case SSL3_ST_SR_CERT_B:
598             if (s->s3->tmp.cert_request) {
599                 ret = ssl3_get_client_certificate(s);
600                 if (ret <= 0)
601                     goto end;
602             }
603             s->init_num = 0;
604             s->state = SSL3_ST_SR_KEY_EXCH_A;
605             break;
606
607         case SSL3_ST_SR_KEY_EXCH_A:
608         case SSL3_ST_SR_KEY_EXCH_B:
609             ret = ssl3_get_client_key_exchange(s);
610             if (ret <= 0)
611                 goto end;
612 #ifndef OPENSSL_NO_SCTP
613             /*
614              * Add new shared key for SCTP-Auth, will be ignored if no SCTP
615              * used.
616              */
617             snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
618                      DTLS1_SCTP_AUTH_LABEL);
619
620             SSL_export_keying_material(s, sctpauthkey,
621                                        sizeof(sctpauthkey), labelbuffer,
622                                        sizeof(labelbuffer), NULL, 0, 0);
623
624             BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
625                      sizeof(sctpauthkey), sctpauthkey);
626 #endif
627
628             s->state = SSL3_ST_SR_CERT_VRFY_A;
629             s->init_num = 0;
630
631             if (ret == 2) {
632                 /*
633                  * For the ECDH ciphersuites when the client sends its ECDH
634                  * pub key in a certificate, the CertificateVerify message is
635                  * not sent.
636                  */
637                 s->state = SSL3_ST_SR_FINISHED_A;
638                 s->init_num = 0;
639             } else if (SSL_USE_SIGALGS(s)) {
640                 s->state = SSL3_ST_SR_CERT_VRFY_A;
641                 s->init_num = 0;
642                 if (!s->session->peer)
643                     break;
644                 if (!s->s3->handshake_buffer) {
645                     SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
646                     return -1;
647                 }
648                 /*
649                  * For sigalgs freeze the handshake buffer. If we support
650                  * extms we've done this already.
651                  */
652                 if (!(s->s3->flags & SSL_SESS_FLAG_EXTMS)) {
653                     s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
654                     if (!ssl3_digest_cached_records(s))
655                         return -1;
656                 }
657             } else {
658                 s->state = SSL3_ST_SR_CERT_VRFY_A;
659                 s->init_num = 0;
660
661                 /*
662                  * We need to get hashes here so if there is a client cert,
663                  * it can be verified
664                  */
665                 s->method->ssl3_enc->cert_verify_mac(s,
666                                                      NID_md5,
667                                                      &(s->s3->
668                                                        tmp.cert_verify_md
669                                                        [0]));
670                 s->method->ssl3_enc->cert_verify_mac(s, NID_sha1,
671                                                      &(s->s3->
672                                                        tmp.cert_verify_md
673                                                        [MD5_DIGEST_LENGTH]));
674             }
675             break;
676
677         case SSL3_ST_SR_CERT_VRFY_A:
678         case SSL3_ST_SR_CERT_VRFY_B:
679             /*
680              * This *should* be the first time we enable CCS, but be
681              * extra careful about surrounding code changes. We need
682              * to set this here because we don't know if we're
683              * expecting a CertificateVerify or not.
684              */
685             if (!s->s3->change_cipher_spec)
686                 s->d1->change_cipher_spec_ok = 1;
687             /* we should decide if we expected this one */
688             ret = ssl3_get_cert_verify(s);
689             if (ret <= 0)
690                 goto end;
691 #ifndef OPENSSL_NO_SCTP
692             if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
693                 state == SSL_ST_RENEGOTIATE)
694                 s->state = DTLS1_SCTP_ST_SR_READ_SOCK;
695             else
696 #endif
697                 s->state = SSL3_ST_SR_FINISHED_A;
698             s->init_num = 0;
699             break;
700
701         case SSL3_ST_SR_FINISHED_A:
702         case SSL3_ST_SR_FINISHED_B:
703             /*
704              * Enable CCS for resumed handshakes.
705              * In a full handshake, we end up here through
706              * SSL3_ST_SR_CERT_VRFY_B, so change_cipher_spec_ok was
707              * already set. Receiving a CCS clears the flag, so make
708              * sure not to re-enable it to ban duplicates.
709              * s->s3->change_cipher_spec is set when a CCS is
710              * processed in d1_pkt.c, and remains set until
711              * the client's Finished message is read.
712              */
713             if (!s->s3->change_cipher_spec)
714                 s->d1->change_cipher_spec_ok = 1;
715             ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A,
716                                     SSL3_ST_SR_FINISHED_B);
717             if (ret <= 0)
718                 goto end;
719             dtls1_stop_timer(s);
720             if (s->hit)
721                 s->state = SSL_ST_OK;
722 #ifndef OPENSSL_NO_TLSEXT
723             else if (s->tlsext_ticket_expected)
724                 s->state = SSL3_ST_SW_SESSION_TICKET_A;
725 #endif
726             else
727                 s->state = SSL3_ST_SW_CHANGE_A;
728             s->init_num = 0;
729             break;
730
731 #ifndef OPENSSL_NO_TLSEXT
732         case SSL3_ST_SW_SESSION_TICKET_A:
733         case SSL3_ST_SW_SESSION_TICKET_B:
734             ret = ssl3_send_newsession_ticket(s);
735             if (ret <= 0)
736                 goto end;
737             s->state = SSL3_ST_SW_CHANGE_A;
738             s->init_num = 0;
739             break;
740
741         case SSL3_ST_SW_CERT_STATUS_A:
742         case SSL3_ST_SW_CERT_STATUS_B:
743             ret = ssl3_send_cert_status(s);
744             if (ret <= 0)
745                 goto end;
746             s->state = SSL3_ST_SW_KEY_EXCH_A;
747             s->init_num = 0;
748             break;
749
750 #endif
751
752         case SSL3_ST_SW_CHANGE_A:
753         case SSL3_ST_SW_CHANGE_B:
754
755             s->session->cipher = s->s3->tmp.new_cipher;
756             if (!s->method->ssl3_enc->setup_key_block(s)) {
757                 ret = -1;
758                 goto end;
759             }
760
761             ret = dtls1_send_change_cipher_spec(s,
762                                                 SSL3_ST_SW_CHANGE_A,
763                                                 SSL3_ST_SW_CHANGE_B);
764
765             if (ret <= 0)
766                 goto end;
767
768 #ifndef OPENSSL_NO_SCTP
769             if (!s->hit) {
770                 /*
771                  * Change to new shared key of SCTP-Auth, will be ignored if
772                  * no SCTP used.
773                  */
774                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
775                          0, NULL);
776             }
777 #endif
778
779             s->state = SSL3_ST_SW_FINISHED_A;
780             s->init_num = 0;
781
782             if (!s->method->ssl3_enc->change_cipher_state(s,
783                                                           SSL3_CHANGE_CIPHER_SERVER_WRITE))
784             {
785                 ret = -1;
786                 goto end;
787             }
788
789             dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
790             break;
791
792         case SSL3_ST_SW_FINISHED_A:
793         case SSL3_ST_SW_FINISHED_B:
794             ret = ssl3_send_finished(s,
795                                      SSL3_ST_SW_FINISHED_A,
796                                      SSL3_ST_SW_FINISHED_B,
797                                      s->method->
798                                      ssl3_enc->server_finished_label,
799                                      s->method->
800                                      ssl3_enc->server_finished_label_len);
801             if (ret <= 0)
802                 goto end;
803             s->state = SSL3_ST_SW_FLUSH;
804             if (s->hit) {
805                 s->s3->tmp.next_state = SSL3_ST_SR_FINISHED_A;
806
807 #ifndef OPENSSL_NO_SCTP
808                 /*
809                  * Change to new shared key of SCTP-Auth, will be ignored if
810                  * no SCTP used.
811                  */
812                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
813                          0, NULL);
814 #endif
815             } else {
816                 s->s3->tmp.next_state = SSL_ST_OK;
817 #ifndef OPENSSL_NO_SCTP
818                 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
819                     s->d1->next_state = s->s3->tmp.next_state;
820                     s->s3->tmp.next_state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
821                 }
822 #endif
823             }
824             s->init_num = 0;
825             break;
826
827         case SSL_ST_OK:
828             /* clean a few things up */
829             ssl3_cleanup_key_block(s);
830
831             /* remove buffering on output */
832             ssl_free_wbio_buffer(s);
833
834             s->init_num = 0;
835
836             if (s->renegotiate == 2) { /* skipped if we just sent a
837                                         * HelloRequest */
838                 s->renegotiate = 0;
839                 s->new_session = 0;
840
841                 ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
842
843                 s->ctx->stats.sess_accept_good++;
844                 /* s->server=1; */
845                 s->handshake_func = dtls1_accept;
846
847                 if (cb != NULL)
848                     cb(s, SSL_CB_HANDSHAKE_DONE, 1);
849             }
850
851             ret = 1;
852
853             /* done handshaking, next message is client hello */
854             s->d1->handshake_read_seq = 0;
855             /* next message is server hello */
856             s->d1->handshake_write_seq = 0;
857             s->d1->next_handshake_write_seq = 0;
858             goto end;
859             /* break; */
860
861         default:
862             SSLerr(SSL_F_DTLS1_ACCEPT, SSL_R_UNKNOWN_STATE);
863             ret = -1;
864             goto end;
865             /* break; */
866         }
867
868         if (!s->s3->tmp.reuse_message && !skip) {
869             if (s->debug) {
870                 if ((ret = BIO_flush(s->wbio)) <= 0)
871                     goto end;
872             }
873
874             if ((cb != NULL) && (s->state != state)) {
875                 new_state = s->state;
876                 s->state = state;
877                 cb(s, SSL_CB_ACCEPT_LOOP, 1);
878                 s->state = new_state;
879             }
880         }
881         skip = 0;
882     }
883  end:
884     /* BIO_flush(s->wbio); */
885
886     s->in_handshake--;
887 #ifndef OPENSSL_NO_SCTP
888     /*
889      * Notify SCTP BIO socket to leave handshake mode and prevent stream
890      * identifier other than 0. Will be ignored if no SCTP is used.
891      */
892     BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
893              s->in_handshake, NULL);
894 #endif
895
896     if (cb != NULL)
897         cb(s, SSL_CB_ACCEPT_EXIT, ret);
898     return (ret);
899 }
900
901 int dtls1_send_hello_verify_request(SSL *s)
902 {
903     unsigned int msg_len;
904     unsigned char *msg, *buf, *p;
905
906     if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) {
907         buf = (unsigned char *)s->init_buf->data;
908
909         msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
910         /* Always use DTLS 1.0 version: see RFC 6347 */
911         *(p++) = DTLS1_VERSION >> 8;
912         *(p++) = DTLS1_VERSION & 0xFF;
913
914         if (s->ctx->app_gen_cookie_cb == NULL ||
915             s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
916                                       &(s->d1->cookie_len)) == 0) {
917             SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,
918                    ERR_R_INTERNAL_ERROR);
919             return 0;
920         }
921
922         *(p++) = (unsigned char)s->d1->cookie_len;
923         memcpy(p, s->d1->cookie, s->d1->cookie_len);
924         p += s->d1->cookie_len;
925         msg_len = p - msg;
926
927         dtls1_set_message_header(s, buf,
928                                  DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0,
929                                  msg_len);
930
931         s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
932         /* number of bytes to write */
933         s->init_num = p - buf;
934         s->init_off = 0;
935     }
936
937     /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
938     return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
939 }