PR: 1829
[oweals/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) 1999-2005 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 #ifndef OPENSSL_NO_DH
125 #include <openssl/dh.h>
126 #endif
127
128 static SSL_METHOD *dtls1_get_server_method(int ver);
129 static int dtls1_send_hello_verify_request(SSL *s);
130
131 static SSL_METHOD *dtls1_get_server_method(int ver)
132         {
133         if (ver == DTLS1_VERSION)
134                 return(DTLSv1_server_method());
135         else
136                 return(NULL);
137         }
138
139 IMPLEMENT_dtls1_meth_func(DTLSv1_server_method,
140                         dtls1_accept,
141                         ssl_undefined_function,
142                         dtls1_get_server_method)
143
144 int dtls1_accept(SSL *s)
145         {
146         BUF_MEM *buf;
147         unsigned long l,Time=(unsigned long)time(NULL);
148         void (*cb)(const SSL *ssl,int type,int val)=NULL;
149         long num1;
150         int ret= -1;
151         int new_state,state,skip=0;
152
153         RAND_add(&Time,sizeof(Time),0);
154         ERR_clear_error();
155         clear_sys_error();
156
157         if (s->info_callback != NULL)
158                 cb=s->info_callback;
159         else if (s->ctx->info_callback != NULL)
160                 cb=s->ctx->info_callback;
161
162         /* init things to blank */
163         s->in_handshake++;
164         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
165
166         if (s->cert == NULL)
167                 {
168                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
169                 return(-1);
170                 }
171
172         for (;;)
173                 {
174                 state=s->state;
175
176                 switch (s->state)
177                         {
178                 case SSL_ST_RENEGOTIATE:
179                         s->new_session=1;
180                         /* s->state=SSL_ST_ACCEPT; */
181
182                 case SSL_ST_BEFORE:
183                 case SSL_ST_ACCEPT:
184                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
185                 case SSL_ST_OK|SSL_ST_ACCEPT:
186
187                         s->server=1;
188                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
189
190                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
191                                 {
192                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
193                                 return -1;
194                                 }
195                         s->type=SSL_ST_ACCEPT;
196
197                         if (s->init_buf == NULL)
198                                 {
199                                 if ((buf=BUF_MEM_new()) == NULL)
200                                         {
201                                         ret= -1;
202                                         goto end;
203                                         }
204                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
205                                         {
206                                         ret= -1;
207                                         goto end;
208                                         }
209                                 s->init_buf=buf;
210                                 }
211
212                         if (!ssl3_setup_buffers(s))
213                                 {
214                                 ret= -1;
215                                 goto end;
216                                 }
217
218                         s->init_num=0;
219
220                         if (s->state != SSL_ST_RENEGOTIATE)
221                                 {
222                                 /* Ok, we now need to push on a buffering BIO so that
223                                  * the output is sent in a way that TCP likes :-)
224                                  */
225                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
226
227                                 ssl3_init_finished_mac(s);
228                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
229                                 s->ctx->stats.sess_accept++;
230                                 }
231                         else
232                                 {
233                                 /* s->state == SSL_ST_RENEGOTIATE,
234                                  * we will just send a HelloRequest */
235                                 s->ctx->stats.sess_accept_renegotiate++;
236                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
237                                 }
238
239             if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
240                 s->d1->send_cookie = 1;
241             else
242                 s->d1->send_cookie = 0;
243
244                         break;
245
246                 case SSL3_ST_SW_HELLO_REQ_A:
247                 case SSL3_ST_SW_HELLO_REQ_B:
248
249                         s->shutdown=0;
250                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
251                         ret=dtls1_send_hello_request(s);
252                         if (ret <= 0) goto end;
253                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
254                         s->state=SSL3_ST_SW_FLUSH;
255                         s->init_num=0;
256
257                         ssl3_init_finished_mac(s);
258                         break;
259
260                 case SSL3_ST_SW_HELLO_REQ_C:
261                         s->state=SSL_ST_OK;
262                         break;
263
264                 case SSL3_ST_SR_CLNT_HELLO_A:
265                 case SSL3_ST_SR_CLNT_HELLO_B:
266                 case SSL3_ST_SR_CLNT_HELLO_C:
267
268                         s->shutdown=0;
269                         ret=ssl3_get_client_hello(s);
270                         if (ret <= 0) goto end;
271                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 0, NULL);
272                         s->new_session = 2;
273
274                         if ( s->d1->send_cookie)
275                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
276                         else
277                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
278
279                         s->init_num=0;
280                         break;
281                         
282                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
283                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
284
285                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
286                         ret = dtls1_send_hello_verify_request(s);
287                         if ( ret <= 0) goto end;
288                         s->d1->send_cookie = 0;
289                         s->state=SSL3_ST_SW_FLUSH;
290                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
291
292                         /* HelloVerifyRequests resets Finished MAC */
293                         if (s->client_version != DTLS1_BAD_VER)
294                                 ssl3_init_finished_mac(s);
295                         break;
296                         
297                 case SSL3_ST_SW_SRVR_HELLO_A:
298                 case SSL3_ST_SW_SRVR_HELLO_B:
299                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
300                         ret=dtls1_send_server_hello(s);
301                         if (ret <= 0) goto end;
302
303                         if (s->hit)
304                                 s->state=SSL3_ST_SW_CHANGE_A;
305                         else
306                                 s->state=SSL3_ST_SW_CERT_A;
307                         s->init_num=0;
308                         break;
309
310                 case SSL3_ST_SW_CERT_A:
311                 case SSL3_ST_SW_CERT_B:
312                         /* Check if it is anon DH */
313                         if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
314                                 {
315                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
316                                 ret=dtls1_send_server_certificate(s);
317                                 if (ret <= 0) goto end;
318                                 }
319                         else
320                                 skip=1;
321                         s->state=SSL3_ST_SW_KEY_EXCH_A;
322                         s->init_num=0;
323                         break;
324
325                 case SSL3_ST_SW_KEY_EXCH_A:
326                 case SSL3_ST_SW_KEY_EXCH_B:
327                         l=s->s3->tmp.new_cipher->algorithms;
328
329                         /* clear this, it may get reset by
330                          * send_server_key_exchange */
331                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
332 #ifndef OPENSSL_NO_KRB5
333                                 && !(l & SSL_KRB5)
334 #endif /* OPENSSL_NO_KRB5 */
335                                 )
336                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
337                                  * even when forbidden by protocol specs
338                                  * (handshake may fail as clients are not required to
339                                  * be able to handle this) */
340                                 s->s3->tmp.use_rsa_tmp=1;
341                         else
342                                 s->s3->tmp.use_rsa_tmp=0;
343
344                         /* only send if a DH key exchange, fortezza or
345                          * RSA but we have a sign only certificate */
346                         if (s->s3->tmp.use_rsa_tmp
347                             || (l & (SSL_DH|SSL_kFZA))
348                             || ((l & SSL_kRSA)
349                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
350                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
351                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
352                                         )
353                                     )
354                                 )
355                             )
356                                 {
357                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
358                                 ret=dtls1_send_server_key_exchange(s);
359                                 if (ret <= 0) goto end;
360                                 }
361                         else
362                                 skip=1;
363
364                         s->state=SSL3_ST_SW_CERT_REQ_A;
365                         s->init_num=0;
366                         break;
367
368                 case SSL3_ST_SW_CERT_REQ_A:
369                 case SSL3_ST_SW_CERT_REQ_B:
370                         if (/* don't request cert unless asked for it: */
371                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
372                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
373                                  * don't request cert during re-negotiation: */
374                                 ((s->session->peer != NULL) &&
375                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
376                                 /* never request cert in anonymous ciphersuites
377                                  * (see section "Certificate request" in SSL 3 drafts
378                                  * and in RFC 2246): */
379                                 ((s->s3->tmp.new_cipher->algorithms & SSL_aNULL) &&
380                                  /* ... except when the application insists on verification
381                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
382                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
383                                  /* never request cert in Kerberos ciphersuites */
384                                 (s->s3->tmp.new_cipher->algorithms & SSL_aKRB5))
385                                 {
386                                 /* no cert request */
387                                 skip=1;
388                                 s->s3->tmp.cert_request=0;
389                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
390                                 }
391                         else
392                                 {
393                                 s->s3->tmp.cert_request=1;
394                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
395                                 ret=dtls1_send_certificate_request(s);
396                                 if (ret <= 0) goto end;
397 #ifndef NETSCAPE_HANG_BUG
398                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
399 #else
400                                 s->state=SSL3_ST_SW_FLUSH;
401                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
402 #endif
403                                 s->init_num=0;
404                                 }
405                         break;
406
407                 case SSL3_ST_SW_SRVR_DONE_A:
408                 case SSL3_ST_SW_SRVR_DONE_B:
409                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 1, NULL);
410                         ret=dtls1_send_server_done(s);
411                         if (ret <= 0) goto end;
412                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
413                         s->state=SSL3_ST_SW_FLUSH;
414                         s->init_num=0;
415                         break;
416                 
417                 case SSL3_ST_SW_FLUSH:
418                         /* number of bytes to be flushed */
419                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
420                         if (num1 > 0)
421                                 {
422                                 s->rwstate=SSL_WRITING;
423                                 num1=BIO_flush(s->wbio);
424                                 if (num1 <= 0) { ret= -1; goto end; }
425                                 s->rwstate=SSL_NOTHING;
426                                 }
427
428                         s->state=s->s3->tmp.next_state;
429                         break;
430
431                 case SSL3_ST_SR_CERT_A:
432                 case SSL3_ST_SR_CERT_B:
433                         /* Check for second client hello (MS SGC) */
434                         ret = ssl3_check_client_hello(s);
435                         if (ret <= 0)
436                                 goto end;
437                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 0, NULL);
438                         if (ret == 2)
439                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
440                         else {
441                                 /* could be sent for a DH cert, even if we
442                                  * have not asked for it :-) */
443                                 ret=ssl3_get_client_certificate(s);
444                                 if (ret <= 0) goto end;
445                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 0, NULL);
446                                 s->init_num=0;
447                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
448                         }
449                         break;
450
451                 case SSL3_ST_SR_KEY_EXCH_A:
452                 case SSL3_ST_SR_KEY_EXCH_B:
453                         ret=ssl3_get_client_key_exchange(s);
454                         if (ret <= 0) goto end;
455                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 0, NULL);
456                         s->state=SSL3_ST_SR_CERT_VRFY_A;
457                         s->init_num=0;
458
459                         /* We need to get hashes here so if there is
460                          * a client cert, it can be verified */ 
461                         s->method->ssl3_enc->cert_verify_mac(s,
462                                 &(s->s3->finish_dgst1),
463                                 &(s->s3->tmp.cert_verify_md[0]));
464                         s->method->ssl3_enc->cert_verify_mac(s,
465                                 &(s->s3->finish_dgst2),
466                                 &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
467
468                         break;
469
470                 case SSL3_ST_SR_CERT_VRFY_A:
471                 case SSL3_ST_SR_CERT_VRFY_B:
472
473                         /* we should decide if we expected this one */
474                         ret=ssl3_get_cert_verify(s);
475                         if (ret <= 0) goto end;
476                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 0, NULL);
477
478                         s->state=SSL3_ST_SR_FINISHED_A;
479                         s->init_num=0;
480                         break;
481
482                 case SSL3_ST_SR_FINISHED_A:
483                 case SSL3_ST_SR_FINISHED_B:
484                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
485                                 SSL3_ST_SR_FINISHED_B);
486                         if (ret <= 0) goto end;
487                         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_TIMEOUT, 0, NULL);
488                         if (s->hit)
489                                 s->state=SSL_ST_OK;
490                         else
491                                 s->state=SSL3_ST_SW_CHANGE_A;
492                         s->init_num=0;
493                         break;
494
495                 case SSL3_ST_SW_CHANGE_A:
496                 case SSL3_ST_SW_CHANGE_B:
497
498                         s->session->cipher=s->s3->tmp.new_cipher;
499                         if (!s->method->ssl3_enc->setup_key_block(s))
500                                 { ret= -1; goto end; }
501
502                         ret=dtls1_send_change_cipher_spec(s,
503                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
504
505                         if (ret <= 0) goto end;
506                         s->state=SSL3_ST_SW_FINISHED_A;
507                         s->init_num=0;
508
509                         if (!s->method->ssl3_enc->change_cipher_state(s,
510                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
511                                 {
512                                 ret= -1;
513                                 goto end;
514                                 }
515
516                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
517                         break;
518
519                 case SSL3_ST_SW_FINISHED_A:
520                 case SSL3_ST_SW_FINISHED_B:
521                         ret=dtls1_send_finished(s,
522                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
523                                 s->method->ssl3_enc->server_finished_label,
524                                 s->method->ssl3_enc->server_finished_label_len);
525                         if (ret <= 0) goto end;
526                         s->state=SSL3_ST_SW_FLUSH;
527                         if (s->hit)
528                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
529                         else
530                                 s->s3->tmp.next_state=SSL_ST_OK;
531                         s->init_num=0;
532                         break;
533
534                 case SSL_ST_OK:
535                         /* clean a few things up */
536                         ssl3_cleanup_key_block(s);
537
538 #if 0
539                         BUF_MEM_free(s->init_buf);
540                         s->init_buf=NULL;
541 #endif
542
543                         /* remove buffering on output */
544                         ssl_free_wbio_buffer(s);
545
546                         s->init_num=0;
547
548                         if (s->new_session == 2) /* skipped if we just sent a HelloRequest */
549                                 {
550                                 /* actually not necessarily a 'new' session unless
551                                  * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
552                                 
553                                 s->new_session=0;
554                                 
555                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
556                                 
557                                 s->ctx->stats.sess_accept_good++;
558                                 /* s->server=1; */
559                                 s->handshake_func=dtls1_accept;
560
561                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
562                                 }
563                         
564                         ret = 1;
565
566                         /* done handshaking, next message is client hello */
567                         s->d1->handshake_read_seq = 0;
568                         /* next message is server hello */
569                         s->d1->handshake_write_seq = 0;
570                         goto end;
571                         /* break; */
572
573                 default:
574                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
575                         ret= -1;
576                         goto end;
577                         /* break; */
578                         }
579                 
580                 if (!s->s3->tmp.reuse_message && !skip)
581                         {
582                         if (s->debug)
583                                 {
584                                 if ((ret=BIO_flush(s->wbio)) <= 0)
585                                         goto end;
586                                 }
587
588
589                         if ((cb != NULL) && (s->state != state))
590                                 {
591                                 new_state=s->state;
592                                 s->state=state;
593                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
594                                 s->state=new_state;
595                                 }
596                         }
597                 skip=0;
598                 }
599 end:
600         /* BIO_flush(s->wbio); */
601
602         s->in_handshake--;
603         if (cb != NULL)
604                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
605         return(ret);
606         }
607
608 int dtls1_send_hello_request(SSL *s)
609         {
610         unsigned char *p;
611
612         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
613                 {
614                 p=(unsigned char *)s->init_buf->data;
615                 p = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);
616
617                 s->state=SSL3_ST_SW_HELLO_REQ_B;
618                 /* number of bytes to write */
619                 s->init_num=DTLS1_HM_HEADER_LENGTH;
620                 s->init_off=0;
621
622                 /* no need to buffer this message, since there are no retransmit 
623                  * requests for it */
624                 }
625
626         /* SSL3_ST_SW_HELLO_REQ_B */
627         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
628         }
629
630 int dtls1_send_hello_verify_request(SSL *s)
631         {
632         unsigned int msg_len;
633         unsigned char *msg, *buf, *p;
634
635         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
636                 {
637                 buf = (unsigned char *)s->init_buf->data;
638
639                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
640                 if (s->client_version == DTLS1_BAD_VER)
641                         *(p++) = DTLS1_BAD_VER>>8,
642                         *(p++) = DTLS1_BAD_VER&0xff;
643                 else
644                         *(p++) = s->version >> 8,
645                         *(p++) = s->version & 0xFF;
646
647                 if (s->ctx->app_gen_cookie_cb != NULL &&
648                     s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 
649                     &(s->d1->cookie_len)) == 0)
650                         {
651                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
652                         return 0;
653                         }
654                 /* else the cookie is assumed to have 
655                  * been initialized by the application */
656
657                 *(p++) = (unsigned char) s->d1->cookie_len;
658                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
659                 p += s->d1->cookie_len;
660                 msg_len = p - msg;
661
662                 dtls1_set_message_header(s, buf,
663                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
664
665                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
666                 /* number of bytes to write */
667                 s->init_num=p-buf;
668                 s->init_off=0;
669
670                 /* buffer the message to handle re-xmits */
671                 dtls1_buffer_message(s, 0);
672                 }
673
674         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
675         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
676         }
677
678 int dtls1_send_server_hello(SSL *s)
679         {
680         unsigned char *buf;
681         unsigned char *p,*d;
682         int i;
683         unsigned int sl;
684         unsigned long l,Time;
685
686         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
687                 {
688                 buf=(unsigned char *)s->init_buf->data;
689                 p=s->s3->server_random;
690                 Time=(unsigned long)time(NULL);                 /* Time */
691                 l2n(Time,p);
692                 RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));
693                 /* Do the message type and length last */
694                 d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);
695
696                 if (s->client_version == DTLS1_BAD_VER)
697                         *(p++)=DTLS1_BAD_VER>>8,
698                         *(p++)=DTLS1_BAD_VER&0xff;
699                 else
700                         *(p++)=s->version>>8,
701                         *(p++)=s->version&0xff;
702
703                 /* Random stuff */
704                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
705                 p+=SSL3_RANDOM_SIZE;
706
707                 /* now in theory we have 3 options to sending back the
708                  * session id.  If it is a re-use, we send back the
709                  * old session-id, if it is a new session, we send
710                  * back the new session-id or we send back a 0 length
711                  * session-id if we want it to be single use.
712                  * Currently I will not implement the '0' length session-id
713                  * 12-Jan-98 - I'll now support the '0' length stuff.
714                  */
715                 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
716                         s->session->session_id_length=0;
717
718                 sl=s->session->session_id_length;
719                 if (sl > sizeof s->session->session_id)
720                         {
721                         SSLerr(SSL_F_DTLS1_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
722                         return -1;
723                         }
724                 *(p++)=sl;
725                 memcpy(p,s->session->session_id,sl);
726                 p+=sl;
727
728                 /* put the cipher */
729                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
730                 p+=i;
731
732                 /* put the compression method */
733 #ifdef OPENSSL_NO_COMP
734                 *(p++)=0;
735 #else
736                 if (s->s3->tmp.new_compression == NULL)
737                         *(p++)=0;
738                 else
739                         *(p++)=s->s3->tmp.new_compression->id;
740 #endif
741
742                 /* do the header */
743                 l=(p-d);
744                 d=buf;
745
746                 d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);
747
748                 s->state=SSL3_ST_SW_SRVR_HELLO_B;
749                 /* number of bytes to write */
750                 s->init_num=p-buf;
751                 s->init_off=0;
752
753                 /* buffer the message to handle re-xmits */
754                 dtls1_buffer_message(s, 0);
755                 }
756
757         /* SSL3_ST_SW_SRVR_HELLO_B */
758         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
759         }
760
761 int dtls1_send_server_done(SSL *s)
762         {
763         unsigned char *p;
764
765         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
766                 {
767                 p=(unsigned char *)s->init_buf->data;
768
769                 /* do the header */
770                 p = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);
771
772                 s->state=SSL3_ST_SW_SRVR_DONE_B;
773                 /* number of bytes to write */
774                 s->init_num=DTLS1_HM_HEADER_LENGTH;
775                 s->init_off=0;
776
777                 /* buffer the message to handle re-xmits */
778                 dtls1_buffer_message(s, 0);
779                 }
780
781         /* SSL3_ST_SW_SRVR_DONE_B */
782         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
783         }
784
785 int dtls1_send_server_key_exchange(SSL *s)
786         {
787 #ifndef OPENSSL_NO_RSA
788         unsigned char *q;
789         int j,num;
790         RSA *rsa;
791         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
792         unsigned int u;
793 #endif
794 #ifndef OPENSSL_NO_DH
795         DH *dh=NULL,*dhp;
796 #endif
797         EVP_PKEY *pkey;
798         unsigned char *p,*d;
799         int al,i;
800         unsigned long type;
801         int n;
802         CERT *cert;
803         BIGNUM *r[4];
804         int nr[4],kn;
805         BUF_MEM *buf;
806         EVP_MD_CTX md_ctx;
807
808         EVP_MD_CTX_init(&md_ctx);
809         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
810                 {
811                 type=s->s3->tmp.new_cipher->algorithms & SSL_MKEY_MASK;
812                 cert=s->cert;
813
814                 buf=s->init_buf;
815
816                 r[0]=r[1]=r[2]=r[3]=NULL;
817                 n=0;
818 #ifndef OPENSSL_NO_RSA
819                 if (type & SSL_kRSA)
820                         {
821                         rsa=cert->rsa_tmp;
822                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
823                                 {
824                                 rsa=s->cert->rsa_tmp_cb(s,
825                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
826                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
827                                 if(rsa == NULL)
828                                 {
829                                         al=SSL_AD_HANDSHAKE_FAILURE;
830                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
831                                         goto f_err;
832                                 }
833                                 RSA_up_ref(rsa);
834                                 cert->rsa_tmp=rsa;
835                                 }
836                         if (rsa == NULL)
837                                 {
838                                 al=SSL_AD_HANDSHAKE_FAILURE;
839                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
840                                 goto f_err;
841                                 }
842                         r[0]=rsa->n;
843                         r[1]=rsa->e;
844                         s->s3->tmp.use_rsa_tmp=1;
845                         }
846                 else
847 #endif
848 #ifndef OPENSSL_NO_DH
849                         if (type & SSL_kEDH)
850                         {
851                         dhp=cert->dh_tmp;
852                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
853                                 dhp=s->cert->dh_tmp_cb(s,
854                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
855                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
856                         if (dhp == NULL)
857                                 {
858                                 al=SSL_AD_HANDSHAKE_FAILURE;
859                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
860                                 goto f_err;
861                                 }
862
863                         if (s->s3->tmp.dh != NULL)
864                                 {
865                                 DH_free(dh);
866                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
867                                 goto err;
868                                 }
869
870                         if ((dh=DHparams_dup(dhp)) == NULL)
871                                 {
872                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
873                                 goto err;
874                                 }
875
876                         s->s3->tmp.dh=dh;
877                         if ((dhp->pub_key == NULL ||
878                              dhp->priv_key == NULL ||
879                              (s->options & SSL_OP_SINGLE_DH_USE)))
880                                 {
881                                 if(!DH_generate_key(dh))
882                                     {
883                                     SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,
884                                            ERR_R_DH_LIB);
885                                     goto err;
886                                     }
887                                 }
888                         else
889                                 {
890                                 dh->pub_key=BN_dup(dhp->pub_key);
891                                 dh->priv_key=BN_dup(dhp->priv_key);
892                                 if ((dh->pub_key == NULL) ||
893                                         (dh->priv_key == NULL))
894                                         {
895                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
896                                         goto err;
897                                         }
898                                 }
899                         r[0]=dh->p;
900                         r[1]=dh->g;
901                         r[2]=dh->pub_key;
902                         }
903                 else 
904 #endif
905                         {
906                         al=SSL_AD_HANDSHAKE_FAILURE;
907                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
908                         goto f_err;
909                         }
910                 for (i=0; r[i] != NULL; i++)
911                         {
912                         nr[i]=BN_num_bytes(r[i]);
913                         n+=2+nr[i];
914                         }
915
916                 if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
917                         {
918                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
919                                 == NULL)
920                                 {
921                                 al=SSL_AD_DECODE_ERROR;
922                                 goto f_err;
923                                 }
924                         kn=EVP_PKEY_size(pkey);
925                         }
926                 else
927                         {
928                         pkey=NULL;
929                         kn=0;
930                         }
931
932                 if (!BUF_MEM_grow_clean(buf,n+DTLS1_HM_HEADER_LENGTH+kn))
933                         {
934                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
935                         goto err;
936                         }
937                 d=(unsigned char *)s->init_buf->data;
938                 p= &(d[DTLS1_HM_HEADER_LENGTH]);
939
940                 for (i=0; r[i] != NULL; i++)
941                         {
942                         s2n(nr[i],p);
943                         BN_bn2bin(r[i],p);
944                         p+=nr[i];
945                         }
946
947                 /* not anonymous */
948                 if (pkey != NULL)
949                         {
950                         /* n is the length of the params, they start at
951                          * &(d[DTLS1_HM_HEADER_LENGTH]) and p points to the space
952                          * at the end. */
953 #ifndef OPENSSL_NO_RSA
954                         if (pkey->type == EVP_PKEY_RSA)
955                                 {
956                                 q=md_buf;
957                                 j=0;
958                                 for (num=2; num > 0; num--)
959                                         {
960                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
961                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
962                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
963                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
964                                         EVP_DigestUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
965                                         EVP_DigestFinal_ex(&md_ctx,q,
966                                                 (unsigned int *)&i);
967                                         q+=i;
968                                         j+=i;
969                                         }
970                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
971                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
972                                         {
973                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
974                                         goto err;
975                                         }
976                                 s2n(u,p);
977                                 n+=u+2;
978                                 }
979                         else
980 #endif
981 #if !defined(OPENSSL_NO_DSA)
982                                 if (pkey->type == EVP_PKEY_DSA)
983                                 {
984                                 /* lets do DSS */
985                                 EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
986                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
987                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
988                                 EVP_SignUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
989                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
990                                         (unsigned int *)&i,pkey))
991                                         {
992                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
993                                         goto err;
994                                         }
995                                 s2n(i,p);
996                                 n+=i+2;
997                                 }
998                         else
999 #endif
1000                                 {
1001                                 /* Is this error check actually needed? */
1002                                 al=SSL_AD_HANDSHAKE_FAILURE;
1003                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
1004                                 goto f_err;
1005                                 }
1006                         }
1007
1008                 d = dtls1_set_message_header(s, d,
1009                         SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);
1010
1011                 /* we should now have things packed up, so lets send
1012                  * it off */
1013                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1014                 s->init_off=0;
1015
1016                 /* buffer the message to handle re-xmits */
1017                 dtls1_buffer_message(s, 0);
1018                 }
1019
1020         s->state = SSL3_ST_SW_KEY_EXCH_B;
1021         EVP_MD_CTX_cleanup(&md_ctx);
1022         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1023 f_err:
1024         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1025 err:
1026         EVP_MD_CTX_cleanup(&md_ctx);
1027         return(-1);
1028         }
1029
1030 int dtls1_send_certificate_request(SSL *s)
1031         {
1032         unsigned char *p,*d;
1033         int i,j,nl,off,n;
1034         STACK_OF(X509_NAME) *sk=NULL;
1035         X509_NAME *name;
1036         BUF_MEM *buf;
1037         unsigned int msg_len;
1038
1039         if (s->state == SSL3_ST_SW_CERT_REQ_A)
1040                 {
1041                 buf=s->init_buf;
1042
1043                 d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
1044
1045                 /* get the list of acceptable cert types */
1046                 p++;
1047                 n=ssl3_get_req_cert_type(s,p);
1048                 d[0]=n;
1049                 p+=n;
1050                 n++;
1051
1052                 off=n;
1053                 p+=2;
1054                 n+=2;
1055
1056                 sk=SSL_get_client_CA_list(s);
1057                 nl=0;
1058                 if (sk != NULL)
1059                         {
1060                         for (i=0; i<sk_X509_NAME_num(sk); i++)
1061                                 {
1062                                 name=sk_X509_NAME_value(sk,i);
1063                                 j=i2d_X509_NAME(name,NULL);
1064                                 if (!BUF_MEM_grow_clean(buf,DTLS1_HM_HEADER_LENGTH+n+j+2))
1065                                         {
1066                                         SSLerr(SSL_F_DTLS1_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
1067                                         goto err;
1068                                         }
1069                                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+n]);
1070                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
1071                                         {
1072                                         s2n(j,p);
1073                                         i2d_X509_NAME(name,&p);
1074                                         n+=2+j;
1075                                         nl+=2+j;
1076                                         }
1077                                 else
1078                                         {
1079                                         d=p;
1080                                         i2d_X509_NAME(name,&p);
1081                                         j-=2; s2n(j,d); j+=2;
1082                                         n+=j;
1083                                         nl+=j;
1084                                         }
1085                                 }
1086                         }
1087                 /* else no CA names */
1088                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+off]);
1089                 s2n(nl,p);
1090
1091                 d=(unsigned char *)buf->data;
1092                 *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
1093                 l2n3(n,d);
1094                 s2n(s->d1->handshake_write_seq,d);
1095                 s->d1->handshake_write_seq++;
1096
1097                 /* we should now have things packed up, so lets send
1098                  * it off */
1099
1100                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1101                 s->init_off=0;
1102 #ifdef NETSCAPE_HANG_BUG
1103 /* XXX: what to do about this? */
1104                 p=(unsigned char *)s->init_buf->data + s->init_num;
1105
1106                 /* do the header */
1107                 *(p++)=SSL3_MT_SERVER_DONE;
1108                 *(p++)=0;
1109                 *(p++)=0;
1110                 *(p++)=0;
1111                 s->init_num += 4;
1112 #endif
1113
1114                 /* XDTLS:  set message header ? */
1115                 msg_len = s->init_num - DTLS1_HM_HEADER_LENGTH;
1116                 dtls1_set_message_header(s, (void *)s->init_buf->data,
1117                         SSL3_MT_CERTIFICATE_REQUEST, msg_len, 0, msg_len);
1118
1119                 /* buffer the message to handle re-xmits */
1120                 dtls1_buffer_message(s, 0);
1121
1122                 s->state = SSL3_ST_SW_CERT_REQ_B;
1123                 }
1124
1125         /* SSL3_ST_SW_CERT_REQ_B */
1126         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1127 err:
1128         return(-1);
1129         }
1130
1131 int dtls1_send_server_certificate(SSL *s)
1132         {
1133         unsigned long l;
1134         X509 *x;
1135
1136         if (s->state == SSL3_ST_SW_CERT_A)
1137                 {
1138                 x=ssl_get_server_send_cert(s);
1139                 if (x == NULL &&
1140                         /* VRS: allow null cert if auth == KRB5 */
1141                         (s->s3->tmp.new_cipher->algorithms
1142                                 & (SSL_MKEY_MASK|SSL_AUTH_MASK))
1143                         != (SSL_aKRB5|SSL_kKRB5))
1144                         {
1145                         SSLerr(SSL_F_DTLS1_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
1146                         return(0);
1147                         }
1148
1149                 l=dtls1_output_cert_chain(s,x);
1150                 s->state=SSL3_ST_SW_CERT_B;
1151                 s->init_num=(int)l;
1152                 s->init_off=0;
1153
1154                 /* buffer the message to handle re-xmits */
1155                 dtls1_buffer_message(s, 0);
1156                 }
1157
1158         /* SSL3_ST_SW_CERT_B */
1159         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1160         }