8a5c5a1cd2204884685cf81c6c1ad57a4a65f761
[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,
147                         DTLSv1_enc_data)
148
149 IMPLEMENT_dtls1_meth_func(DTLS1_2_VERSION,
150                         DTLSv1_2_server_method,
151                         dtls1_accept,
152                         ssl_undefined_function,
153                         dtls1_get_server_method,
154                         DTLSv1_2_enc_data)
155
156 IMPLEMENT_dtls1_meth_func(DTLS_ANY_VERSION,
157                         DTLS_server_method,
158                         dtls1_accept,
159                         ssl_undefined_function,
160                         dtls1_get_server_method,
161                         DTLSv1_2_enc_data)
162
163 int dtls1_accept(SSL *s)
164         {
165         BUF_MEM *buf;
166         unsigned long Time=(unsigned long)time(NULL);
167         void (*cb)(const SSL *ssl,int type,int val)=NULL;
168         unsigned long alg_k;
169         int ret= -1;
170         int new_state,state,skip=0;
171         int listen;
172 #ifndef OPENSSL_NO_SCTP
173         unsigned char sctpauthkey[64];
174         char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
175 #endif
176
177         RAND_add(&Time,sizeof(Time),0);
178         ERR_clear_error();
179         clear_sys_error();
180
181         if (s->info_callback != NULL)
182                 cb=s->info_callback;
183         else if (s->ctx->info_callback != NULL)
184                 cb=s->ctx->info_callback;
185         
186         listen = s->d1->listen;
187
188         /* init things to blank */
189         s->in_handshake++;
190         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
191
192         s->d1->listen = listen;
193 #ifndef OPENSSL_NO_SCTP
194         /* Notify SCTP BIO socket to enter handshake
195          * mode and prevent stream identifier other
196          * 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, s->in_handshake, NULL);
199 #endif
200
201         if (s->cert == NULL)
202                 {
203                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
204                 return(-1);
205                 }
206
207 #ifndef OPENSSL_NO_HEARTBEATS
208         /* If we're awaiting a HeartbeatResponse, pretend we
209          * already got and don't await it anymore, because
210          * Heartbeats don't make sense during handshakes anyway.
211          */
212         if (s->tlsext_hb_pending)
213                 {
214                 dtls1_stop_timer(s);
215                 s->tlsext_hb_pending = 0;
216                 s->tlsext_hb_seq++;
217                 }
218 #endif
219
220         for (;;)
221                 {
222                 state=s->state;
223
224                 switch (s->state)
225                         {
226                 case SSL_ST_RENEGOTIATE:
227                         s->renegotiate=1;
228                         /* s->state=SSL_ST_ACCEPT; */
229
230                 case SSL_ST_BEFORE:
231                 case SSL_ST_ACCEPT:
232                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
233                 case SSL_ST_OK|SSL_ST_ACCEPT:
234
235                         s->server=1;
236                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
237
238                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
239                                 {
240                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
241                                 return -1;
242                                 }
243                         s->type=SSL_ST_ACCEPT;
244
245                         if (s->init_buf == NULL)
246                                 {
247                                 if ((buf=BUF_MEM_new()) == NULL)
248                                         {
249                                         ret= -1;
250                                         goto end;
251                                         }
252                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
253                                         {
254                                         BUF_MEM_free(buf);
255                                         ret= -1;
256                                         goto end;
257                                         }
258                                 s->init_buf=buf;
259                                 }
260
261                         if (!ssl3_setup_buffers(s))
262                                 {
263                                 ret= -1;
264                                 goto end;
265                                 }
266
267                         s->init_num=0;
268                         s->d1->change_cipher_spec_ok = 0;
269                         /* Should have been reset by ssl3_get_finished, too. */
270                         s->s3->change_cipher_spec = 0;
271
272                         if (s->state != SSL_ST_RENEGOTIATE)
273                                 {
274                                 /* Ok, we now need to push on a buffering BIO so that
275                                  * the output is sent in a way that TCP likes :-)
276                                  * ...but not with SCTP :-)
277                                  */
278 #ifndef OPENSSL_NO_SCTP
279                                 if (!BIO_dgram_is_sctp(SSL_get_wbio(s)))
280 #endif
281                                         if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
282
283                                 ssl3_init_finished_mac(s);
284                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
285                                 s->ctx->stats.sess_accept++;
286                                 }
287                         else
288                                 {
289                                 /* s->state == SSL_ST_RENEGOTIATE,
290                                  * we will just send a HelloRequest */
291                                 s->ctx->stats.sess_accept_renegotiate++;
292                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
293                                 }
294
295                         break;
296
297                 case SSL3_ST_SW_HELLO_REQ_A:
298                 case SSL3_ST_SW_HELLO_REQ_B:
299
300                         s->shutdown=0;
301                         dtls1_clear_record_buffer(s);
302                         dtls1_start_timer(s);
303                         ret=ssl3_send_hello_request(s);
304                         if (ret <= 0) goto end;
305                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
306                         s->state=SSL3_ST_SW_FLUSH;
307                         s->init_num=0;
308
309                         ssl3_init_finished_mac(s);
310                         break;
311
312                 case SSL3_ST_SW_HELLO_REQ_C:
313                         s->state=SSL_ST_OK;
314                         break;
315
316                 case SSL3_ST_SR_CLNT_HELLO_A:
317                 case SSL3_ST_SR_CLNT_HELLO_B:
318                 case SSL3_ST_SR_CLNT_HELLO_C:
319
320                         s->shutdown=0;
321                         ret=ssl3_get_client_hello(s);
322                         if (ret <= 0) goto end;
323                         dtls1_stop_timer(s);
324
325                         if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
326                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
327                         else
328                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
329
330                         s->init_num=0;
331
332                         /* Reflect ClientHello sequence to remain stateless while listening */
333                         if (listen)
334                                 {
335                                 memcpy(s->s3->write_sequence, s->s3->read_sequence, sizeof(s->s3->write_sequence));
336                                 }
337
338                         /* If we're just listening, stop here */
339                         if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A)
340                                 {
341                                 ret = 2;
342                                 s->d1->listen = 0;
343                                 /* Set expected sequence numbers
344                                  * to continue the handshake.
345                                  */
346                                 s->d1->handshake_read_seq = 2;
347                                 s->d1->handshake_write_seq = 1;
348                                 s->d1->next_handshake_write_seq = 1;
349                                 goto end;
350                                 }
351                         
352                         break;
353                         
354                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
355                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
356
357                         ret = dtls1_send_hello_verify_request(s);
358                         if ( ret <= 0) goto end;
359                         s->state=SSL3_ST_SW_FLUSH;
360                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
361
362                         /* HelloVerifyRequest resets Finished MAC */
363                         if (s->version != DTLS1_BAD_VER)
364                                 ssl3_init_finished_mac(s);
365                         break;
366                         
367 #ifndef OPENSSL_NO_SCTP
368                 case DTLS1_SCTP_ST_SR_READ_SOCK:
369                         
370                         if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))                
371                                 {
372                                 s->s3->in_read_app_data=2;
373                                 s->rwstate=SSL_READING;
374                                 BIO_clear_retry_flags(SSL_get_rbio(s));
375                                 BIO_set_retry_read(SSL_get_rbio(s));
376                                 ret = -1;
377                                 goto end;
378                                 }
379                         
380                         s->state=SSL3_ST_SR_FINISHED_A;
381                         break;
382                         
383                 case DTLS1_SCTP_ST_SW_WRITE_SOCK:
384                         ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
385                         if (ret < 0) goto end;
386                         
387                         if (ret == 0)
388                                 {
389                                 if (s->d1->next_state != SSL_ST_OK)
390                                         {
391                                         s->s3->in_read_app_data=2;
392                                         s->rwstate=SSL_READING;
393                                         BIO_clear_retry_flags(SSL_get_rbio(s));
394                                         BIO_set_retry_read(SSL_get_rbio(s));
395                                         ret = -1;
396                                         goto end;
397                                         }
398                                 }
399
400                         s->state=s->d1->next_state;
401                         break;
402 #endif
403
404                 case SSL3_ST_SW_SRVR_HELLO_A:
405                 case SSL3_ST_SW_SRVR_HELLO_B:
406                         s->renegotiate = 2;
407                         dtls1_start_timer(s);
408                         ret=ssl3_send_server_hello(s);
409                         if (ret <= 0) goto end;
410
411                         if (s->hit)
412                                 {
413 #ifndef OPENSSL_NO_SCTP
414                                 /* Add new shared key for SCTP-Auth,
415                                  * will be ignored if no SCTP used.
416                                  */
417                                 snprintf((char*) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
418                                          DTLS1_SCTP_AUTH_LABEL);
419
420                                 SSL_export_keying_material(s, sctpauthkey,
421                                                            sizeof(sctpauthkey), labelbuffer,
422                                                            sizeof(labelbuffer), NULL, 0, 0);
423                                 
424                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
425                          sizeof(sctpauthkey), sctpauthkey);
426 #endif
427 #ifndef OPENSSL_NO_TLSEXT
428                                 if (s->tlsext_ticket_expected)
429                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
430                                 else
431                                         s->state=SSL3_ST_SW_CHANGE_A;
432 #else
433                                 s->state=SSL3_ST_SW_CHANGE_A;
434 #endif
435                                 }
436                         else
437                                 s->state=SSL3_ST_SW_CERT_A;
438                         s->init_num=0;
439                         break;
440
441                 case SSL3_ST_SW_CERT_A:
442                 case SSL3_ST_SW_CERT_B:
443                         /* Check if it is anon DH or normal PSK */
444                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
445                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
446                                 {
447                                 dtls1_start_timer(s);
448                                 ret=ssl3_send_server_certificate(s);
449                                 if (ret <= 0) goto end;
450 #ifndef OPENSSL_NO_TLSEXT
451                                 if (s->tlsext_status_expected)
452                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
453                                 else
454                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
455                                 }
456                         else
457                                 {
458                                 skip = 1;
459                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
460                                 }
461 #else
462                                 }
463                         else
464                                 skip=1;
465
466                         s->state=SSL3_ST_SW_KEY_EXCH_A;
467 #endif
468                         s->init_num=0;
469                         break;
470
471                 case SSL3_ST_SW_KEY_EXCH_A:
472                 case SSL3_ST_SW_KEY_EXCH_B:
473                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
474
475                         /*
476                          * clear this, it may get reset by
477                          * send_server_key_exchange
478                          */
479                         s->s3->tmp.use_rsa_tmp=0;
480
481                         /* only send if a DH key exchange or
482                          * RSA but we have a sign only certificate */
483                         if (
484                         /* PSK: send ServerKeyExchange if PSK identity
485                          * hint if provided */
486 #ifndef OPENSSL_NO_PSK
487                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
488 #endif
489                             || (alg_k & (SSL_kDHE|SSL_kDHr|SSL_kDHd))
490                             || (alg_k & SSL_kECDHE)
491                             || ((alg_k & SSL_kRSA)
492                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
493                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
494                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
495                                         )
496                                     )
497                                 )
498                             )
499                                 {
500                                 dtls1_start_timer(s);
501                                 ret=ssl3_send_server_key_exchange(s);
502                                 if (ret <= 0) goto end;
503                                 }
504                         else
505                                 skip=1;
506
507                         s->state=SSL3_ST_SW_CERT_REQ_A;
508                         s->init_num=0;
509                         break;
510
511                 case SSL3_ST_SW_CERT_REQ_A:
512                 case SSL3_ST_SW_CERT_REQ_B:
513                         if (/* don't request cert unless asked for it: */
514                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
515                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
516                                  * don't request cert during re-negotiation: */
517                                 ((s->session->peer != NULL) &&
518                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
519                                 /* never request cert in anonymous ciphersuites
520                                  * (see section "Certificate request" in SSL 3 drafts
521                                  * and in RFC 2246): */
522                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
523                                  /* ... except when the application insists on verification
524                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
525                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
526                                  /* never request cert in Kerberos ciphersuites */
527                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
528                                 /* With normal PSK Certificates and
529                                  * Certificate Requests are omitted */
530                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
531                                 {
532                                 /* no cert request */
533                                 skip=1;
534                                 s->s3->tmp.cert_request=0;
535                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
536 #ifndef OPENSSL_NO_SCTP
537                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
538                                         {
539                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
540                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
541                                         }
542 #endif
543                                 }
544                         else
545                                 {
546                                 s->s3->tmp.cert_request=1;
547                                 dtls1_start_timer(s);
548                                 ret=ssl3_send_certificate_request(s);
549                                 if (ret <= 0) goto end;
550 #ifndef NETSCAPE_HANG_BUG
551                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
552 #ifndef OPENSSL_NO_SCTP
553                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
554                                         {
555                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
556                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
557                                         }
558 #endif
559 #else
560                                 s->state=SSL3_ST_SW_FLUSH;
561                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
562 #ifndef OPENSSL_NO_SCTP
563                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
564                                         {
565                                         s->d1->next_state = s->s3->tmp.next_state;
566                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
567                                         }
568 #endif
569 #endif
570                                 s->init_num=0;
571                                 }
572                         break;
573
574                 case SSL3_ST_SW_SRVR_DONE_A:
575                 case SSL3_ST_SW_SRVR_DONE_B:
576                         dtls1_start_timer(s);
577                         ret=ssl3_send_server_done(s);
578                         if (ret <= 0) goto end;
579                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
580                         s->state=SSL3_ST_SW_FLUSH;
581                         s->init_num=0;
582                         break;
583                 
584                 case SSL3_ST_SW_FLUSH:
585                         s->rwstate=SSL_WRITING;
586                         if (BIO_flush(s->wbio) <= 0)
587                                 {
588                                 /* If the write error was fatal, stop trying */
589                                 if (!BIO_should_retry(s->wbio))
590                                         {
591                                         s->rwstate=SSL_NOTHING;
592                                         s->state=s->s3->tmp.next_state;
593                                         }
594                                 
595                                 ret= -1;
596                                 goto end;
597                                 }
598                         s->rwstate=SSL_NOTHING;
599                         s->state=s->s3->tmp.next_state;
600                         break;
601
602                 case SSL3_ST_SR_CERT_A:
603                 case SSL3_ST_SR_CERT_B:
604                         if (s->s3->tmp.cert_request)
605                                 {
606                                 ret=ssl3_get_client_certificate(s);
607                                 if (ret <= 0) goto end;
608                                 }
609                         s->init_num=0;
610                         s->state=SSL3_ST_SR_KEY_EXCH_A;
611                         break;
612
613                 case SSL3_ST_SR_KEY_EXCH_A:
614                 case SSL3_ST_SR_KEY_EXCH_B:
615                         ret=ssl3_get_client_key_exchange(s);
616                         if (ret <= 0) goto end;
617 #ifndef OPENSSL_NO_SCTP
618                         /* Add new shared key for SCTP-Auth,
619                          * will be ignored if no SCTP used.
620                          */
621                         snprintf((char *) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
622                                  DTLS1_SCTP_AUTH_LABEL);
623
624                         SSL_export_keying_material(s, sctpauthkey,
625                                                    sizeof(sctpauthkey), labelbuffer,
626                                                    sizeof(labelbuffer), NULL, 0, 0);
627
628                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
629                                  sizeof(sctpauthkey), sctpauthkey);
630 #endif
631
632                         s->state=SSL3_ST_SR_CERT_VRFY_A;
633                         s->init_num=0;
634
635                         if (ret == 2)
636                                 {
637                                 /* For the ECDH ciphersuites when
638                                  * the client sends its ECDH pub key in
639                                  * a certificate, the CertificateVerify
640                                  * message is not sent.
641                                  */
642                                 s->state=SSL3_ST_SR_FINISHED_A;
643                                 s->init_num = 0;
644                                 }
645                         else if (SSL_USE_SIGALGS(s))
646                                 {
647                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
648                                 s->init_num=0;
649                                 if (!s->session->peer)
650                                         break;
651                                 /* For sigalgs freeze the handshake buffer
652                                  * at this point and digest cached records.
653                                  */
654                                 if (!s->s3->handshake_buffer)
655                                         {
656                                         SSLerr(SSL_F_DTLS1_ACCEPT,ERR_R_INTERNAL_ERROR);
657                                         return -1;
658                                         }
659                                 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
660                                 if (!ssl3_digest_cached_records(s))
661                                         return -1;
662                                 }
663                         else
664                                 {
665                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
666                                 s->init_num=0;
667
668                                 /* We need to get hashes here so if there is
669                                  * a client cert, it can be verified */ 
670                                 s->method->ssl3_enc->cert_verify_mac(s,
671                                         NID_md5,
672                                         &(s->s3->tmp.cert_verify_md[0]));
673                                 s->method->ssl3_enc->cert_verify_mac(s,
674                                         NID_sha1,
675                                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
676                                 }
677                         break;
678
679                 case SSL3_ST_SR_CERT_VRFY_A:
680                 case SSL3_ST_SR_CERT_VRFY_B:
681                         /*
682                          * This *should* be the first time we enable CCS, but be
683                          * extra careful about surrounding code changes. We need
684                          * to set this here because we don't know if we're
685                          * expecting a CertificateVerify or not.
686                          */
687                         if (!s->s3->change_cipher_spec)
688                                 s->d1->change_cipher_spec_ok = 1;
689                         /* we should decide if we expected this one */
690                         ret=ssl3_get_cert_verify(s);
691                         if (ret <= 0) 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) 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) goto end;
736                         s->state=SSL3_ST_SW_CHANGE_A;
737                         s->init_num=0;
738                         break;
739
740                 case SSL3_ST_SW_CERT_STATUS_A:
741                 case SSL3_ST_SW_CERT_STATUS_B:
742                         ret=ssl3_send_cert_status(s);
743                         if (ret <= 0) goto end;
744                         s->state=SSL3_ST_SW_KEY_EXCH_A;
745                         s->init_num=0;
746                         break;
747
748 #endif
749
750                 case SSL3_ST_SW_CHANGE_A:
751                 case SSL3_ST_SW_CHANGE_B:
752
753                         s->session->cipher=s->s3->tmp.new_cipher;
754                         if (!s->method->ssl3_enc->setup_key_block(s))
755                                 { ret= -1; goto end; }
756
757                         ret=dtls1_send_change_cipher_spec(s,
758                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
759
760                         if (ret <= 0) goto end;
761
762 #ifndef OPENSSL_NO_SCTP
763                         if (!s->hit)
764                                 {
765                                 /* Change to new shared key of SCTP-Auth,
766                                  * will be ignored if no SCTP used.
767                                  */
768                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
769                                 }
770 #endif
771
772                         s->state=SSL3_ST_SW_FINISHED_A;
773                         s->init_num=0;
774
775                         if (!s->method->ssl3_enc->change_cipher_state(s,
776                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
777                                 {
778                                 ret= -1;
779                                 goto end;
780                                 }
781
782                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
783                         break;
784
785                 case SSL3_ST_SW_FINISHED_A:
786                 case SSL3_ST_SW_FINISHED_B:
787                         ret=ssl3_send_finished(s,
788                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
789                                 s->method->ssl3_enc->server_finished_label,
790                                 s->method->ssl3_enc->server_finished_label_len);
791                         if (ret <= 0) goto end;
792                         s->state=SSL3_ST_SW_FLUSH;
793                         if (s->hit)
794                                 {
795                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
796
797 #ifndef OPENSSL_NO_SCTP
798                                 /* Change to new shared key of SCTP-Auth,
799                                  * will be ignored if no SCTP used.
800                                  */
801                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
802 #endif
803                                 }
804                         else
805                                 {
806                                 s->s3->tmp.next_state=SSL_ST_OK;
807 #ifndef OPENSSL_NO_SCTP
808                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
809                                         {
810                                         s->d1->next_state = s->s3->tmp.next_state;
811                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
812                                         }
813 #endif
814                                 }
815                         s->init_num=0;
816                         break;
817
818                 case SSL_ST_OK:
819                         /* clean a few things up */
820                         ssl3_cleanup_key_block(s);
821
822 #if 0
823                         BUF_MEM_free(s->init_buf);
824                         s->init_buf=NULL;
825 #endif
826
827                         /* remove buffering on output */
828                         ssl_free_wbio_buffer(s);
829
830                         s->init_num=0;
831
832                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
833                                 {
834                                 s->renegotiate=0;
835                                 s->new_session=0;
836                                 
837                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
838                                 
839                                 s->ctx->stats.sess_accept_good++;
840                                 /* s->server=1; */
841                                 s->handshake_func=dtls1_accept;
842
843                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
844                                 }
845                         
846                         ret = 1;
847
848                         /* done handshaking, next message is client hello */
849                         s->d1->handshake_read_seq = 0;
850                         /* next message is server hello */
851                         s->d1->handshake_write_seq = 0;
852                         s->d1->next_handshake_write_seq = 0;
853                         goto end;
854                         /* break; */
855
856                 default:
857                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
858                         ret= -1;
859                         goto end;
860                         /* break; */
861                         }
862                 
863                 if (!s->s3->tmp.reuse_message && !skip)
864                         {
865                         if (s->debug)
866                                 {
867                                 if ((ret=BIO_flush(s->wbio)) <= 0)
868                                         goto end;
869                                 }
870
871
872                         if ((cb != NULL) && (s->state != state))
873                                 {
874                                 new_state=s->state;
875                                 s->state=state;
876                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
877                                 s->state=new_state;
878                                 }
879                         }
880                 skip=0;
881                 }
882 end:
883         /* BIO_flush(s->wbio); */
884
885         s->in_handshake--;
886 #ifndef OPENSSL_NO_SCTP
887                 /* Notify SCTP BIO socket to leave handshake
888                  * mode and prevent stream identifier other
889                  * than 0. Will be ignored if no SCTP is used.
890                  */
891                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
892 #endif
893
894         if (cb != NULL)
895                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
896         return(ret);
897         }
898
899 int dtls1_send_hello_verify_request(SSL *s)
900         {
901         unsigned int msg_len;
902         unsigned char *msg, *buf, *p;
903
904         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
905                 {
906                 buf = (unsigned char *)s->init_buf->data;
907
908                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
909                 /* Always use DTLS 1.0 version: see RFC 6347 */
910                 *(p++) = DTLS1_VERSION >> 8;
911                 *(p++) = DTLS1_VERSION & 0xFF;
912
913                 if (s->ctx->app_gen_cookie_cb == NULL ||
914                      s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
915                          &(s->d1->cookie_len)) == 0)
916                         {
917                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
918                         return 0;
919                         }
920
921                 *(p++) = (unsigned char) s->d1->cookie_len;
922                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
923                 p += s->d1->cookie_len;
924                 msg_len = p - msg;
925
926                 dtls1_set_message_header(s, buf,
927                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
928
929                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
930                 /* number of bytes to write */
931                 s->init_num=p-buf;
932                 s->init_off=0;
933                 }
934
935         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
936         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
937         }