Add DTLS support.
[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
125 static SSL_METHOD *dtls1_get_server_method(int ver);
126 static int dtls1_send_hello_verify_request(SSL *s);
127
128 static SSL_METHOD *dtls1_get_server_method(int ver)
129         {
130         if (ver == DTLS1_VERSION)
131                 return(DTLSv1_server_method());
132         else
133                 return(NULL);
134         }
135
136 SSL_METHOD *DTLSv1_server_method(void)
137         {
138         static int init=1;
139         static SSL_METHOD DTLSv1_server_data;
140
141         if (init)
142                 {
143                 CRYPTO_w_lock(CRYPTO_LOCK_SSL_METHOD);
144
145                 if (init)
146                         {
147                         memcpy((char *)&DTLSv1_server_data,(char *)dtlsv1_base_method(),
148                                 sizeof(SSL_METHOD));
149                         DTLSv1_server_data.ssl_accept=dtls1_accept;
150                         DTLSv1_server_data.get_ssl_method=dtls1_get_server_method;
151                         init=0;
152                         }
153                         
154                 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_METHOD);
155                 }
156         return(&DTLSv1_server_data);
157         }
158
159 int dtls1_accept(SSL *s)
160         {
161         BUF_MEM *buf;
162         unsigned long l,Time=time(NULL);
163         void (*cb)(const SSL *ssl,int type,int val)=NULL;
164         long num1;
165         int ret= -1;
166         int new_state,state,skip=0;
167
168         RAND_add(&Time,sizeof(Time),0);
169         ERR_clear_error();
170         clear_sys_error();
171
172         if (s->info_callback != NULL)
173                 cb=s->info_callback;
174         else if (s->ctx->info_callback != NULL)
175                 cb=s->ctx->info_callback;
176
177         /* init things to blank */
178         s->in_handshake++;
179         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
180
181         if (s->cert == NULL)
182                 {
183                 SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
184                 return(-1);
185                 }
186
187         for (;;)
188                 {
189                 state=s->state;
190
191                 switch (s->state)
192                         {
193                 case SSL_ST_RENEGOTIATE:
194                         s->new_session=1;
195                         /* s->state=SSL_ST_ACCEPT; */
196
197                 case SSL_ST_BEFORE:
198                 case SSL_ST_ACCEPT:
199                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
200                 case SSL_ST_OK|SSL_ST_ACCEPT:
201
202                         s->server=1;
203                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
204
205                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
206                                 {
207                                 SSLerr(SSL_F_SSL3_ACCEPT, ERR_R_INTERNAL_ERROR);
208                                 return -1;
209                                 }
210                         s->type=SSL_ST_ACCEPT;
211
212                         if (s->init_buf == NULL)
213                                 {
214                                 if ((buf=BUF_MEM_new()) == NULL)
215                                         {
216                                         ret= -1;
217                                         goto end;
218                                         }
219                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
220                                         {
221                                         ret= -1;
222                                         goto end;
223                                         }
224                                 s->init_buf=buf;
225                                 }
226
227                         if (!ssl3_setup_buffers(s))
228                                 {
229                                 ret= -1;
230                                 goto end;
231                                 }
232
233                         s->init_num=0;
234
235                         if (s->state != SSL_ST_RENEGOTIATE)
236                                 {
237                                 /* Ok, we now need to push on a buffering BIO so that
238                                  * the output is sent in a way that TCP likes :-)
239                                  */
240                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
241
242                                 ssl3_init_finished_mac(s);
243                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
244                                 s->ctx->stats.sess_accept++;
245                                 }
246                         else
247                                 {
248                                 /* s->state == SSL_ST_RENEGOTIATE,
249                                  * we will just send a HelloRequest */
250                                 s->ctx->stats.sess_accept_renegotiate++;
251                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
252                                 }
253
254             if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
255                 s->d1->send_cookie = 1;
256             else
257                 s->d1->send_cookie = 0;
258
259                         break;
260
261                 case SSL3_ST_SW_HELLO_REQ_A:
262                 case SSL3_ST_SW_HELLO_REQ_B:
263
264                         s->shutdown=0;
265                         ret=dtls1_send_hello_request(s);
266                         if (ret <= 0) goto end;
267                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
268                         s->state=SSL3_ST_SW_FLUSH;
269                         s->init_num=0;
270
271                         ssl3_init_finished_mac(s);
272                         break;
273
274                 case SSL3_ST_SW_HELLO_REQ_C:
275                         s->state=SSL_ST_OK;
276                         break;
277
278                 case SSL3_ST_SR_CLNT_HELLO_A:
279                 case SSL3_ST_SR_CLNT_HELLO_B:
280                 case SSL3_ST_SR_CLNT_HELLO_C:
281
282                         s->shutdown=0;
283                         ret=ssl3_get_client_hello(s);
284                         if (ret <= 0) goto end;
285                         s->new_session = 2;
286
287                         if ( s->d1->send_cookie)
288                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
289                         else
290                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
291
292                         s->init_num=0;
293                         break;
294                         
295                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
296                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
297
298                         ret = dtls1_send_hello_verify_request(s);
299                         if ( ret <= 0) goto end;
300                         s->d1->send_cookie = 0;
301                         s->state=SSL3_ST_SW_FLUSH;
302                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
303                         break;
304                         
305                 case SSL3_ST_SW_SRVR_HELLO_A:
306                 case SSL3_ST_SW_SRVR_HELLO_B:
307                         ret=dtls1_send_server_hello(s);
308                         if (ret <= 0) goto end;
309
310                         if (s->hit)
311                                 s->state=SSL3_ST_SW_CHANGE_A;
312                         else
313                                 s->state=SSL3_ST_SW_CERT_A;
314                         s->init_num=0;
315                         break;
316
317                 case SSL3_ST_SW_CERT_A:
318                 case SSL3_ST_SW_CERT_B:
319                         /* Check if it is anon DH */
320                         if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
321                                 {
322                                 ret=dtls1_send_server_certificate(s);
323                                 if (ret <= 0) goto end;
324                                 }
325                         else
326                                 skip=1;
327                         s->state=SSL3_ST_SW_KEY_EXCH_A;
328                         s->init_num=0;
329                         break;
330
331                 case SSL3_ST_SW_KEY_EXCH_A:
332                 case SSL3_ST_SW_KEY_EXCH_B:
333                         l=s->s3->tmp.new_cipher->algorithms;
334
335                         /* clear this, it may get reset by
336                          * send_server_key_exchange */
337                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
338 #ifndef OPENSSL_NO_KRB5
339                                 && !(l & SSL_KRB5)
340 #endif /* OPENSSL_NO_KRB5 */
341                                 )
342                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
343                                  * even when forbidden by protocol specs
344                                  * (handshake may fail as clients are not required to
345                                  * be able to handle this) */
346                                 s->s3->tmp.use_rsa_tmp=1;
347                         else
348                                 s->s3->tmp.use_rsa_tmp=0;
349
350                         /* only send if a DH key exchange, fortezza or
351                          * RSA but we have a sign only certificate */
352                         if (s->s3->tmp.use_rsa_tmp
353                             || (l & (SSL_DH|SSL_kFZA))
354                             || ((l & SSL_kRSA)
355                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
356                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
357                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
358                                         )
359                                     )
360                                 )
361                             )
362                                 {
363                                 ret=dtls1_send_server_key_exchange(s);
364                                 if (ret <= 0) goto end;
365                                 }
366                         else
367                                 skip=1;
368
369                         s->state=SSL3_ST_SW_CERT_REQ_A;
370                         s->init_num=0;
371                         break;
372
373                 case SSL3_ST_SW_CERT_REQ_A:
374                 case SSL3_ST_SW_CERT_REQ_B:
375                         if (/* don't request cert unless asked for it: */
376                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
377                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
378                                  * don't request cert during re-negotiation: */
379                                 ((s->session->peer != NULL) &&
380                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
381                                 /* never request cert in anonymous ciphersuites
382                                  * (see section "Certificate request" in SSL 3 drafts
383                                  * and in RFC 2246): */
384                                 ((s->s3->tmp.new_cipher->algorithms & SSL_aNULL) &&
385                                  /* ... except when the application insists on verification
386                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
387                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
388                                  /* never request cert in Kerberos ciphersuites */
389                                 (s->s3->tmp.new_cipher->algorithms & SSL_aKRB5))
390                                 {
391                                 /* no cert request */
392                                 skip=1;
393                                 s->s3->tmp.cert_request=0;
394                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
395                                 }
396                         else
397                                 {
398                                 s->s3->tmp.cert_request=1;
399                                 ret=dtls1_send_certificate_request(s);
400                                 if (ret <= 0) goto end;
401 #ifndef NETSCAPE_HANG_BUG
402                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
403 #else
404                                 s->state=SSL3_ST_SW_FLUSH;
405                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
406 #endif
407                                 s->init_num=0;
408                                 }
409                         break;
410
411                 case SSL3_ST_SW_SRVR_DONE_A:
412                 case SSL3_ST_SW_SRVR_DONE_B:
413                         ret=dtls1_send_server_done(s);
414                         if (ret <= 0) goto end;
415                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
416                         s->state=SSL3_ST_SW_FLUSH;
417                         s->init_num=0;
418                         break;
419                 
420                 case SSL3_ST_SW_FLUSH:
421                         /* number of bytes to be flushed */
422                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
423                         if (num1 > 0)
424                                 {
425                                 s->rwstate=SSL_WRITING;
426                                 num1=BIO_flush(s->wbio);
427                                 if (num1 <= 0) { ret= -1; goto end; }
428                                 s->rwstate=SSL_NOTHING;
429                                 }
430
431                         s->state=s->s3->tmp.next_state;
432                         break;
433
434                 case SSL3_ST_SR_CERT_A:
435                 case SSL3_ST_SR_CERT_B:
436                         /* Check for second client hello (MS SGC) */
437                         ret = ssl3_check_client_hello(s);
438                         if (ret <= 0)
439                                 goto end;
440                         if (ret == 2)
441                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
442                         else {
443                                 /* could be sent for a DH cert, even if we
444                                  * have not asked for it :-) */
445                                 ret=ssl3_get_client_certificate(s);
446                                 if (ret <= 0) goto end;
447                                 s->init_num=0;
448                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
449                         }
450                         break;
451
452                 case SSL3_ST_SR_KEY_EXCH_A:
453                 case SSL3_ST_SR_KEY_EXCH_B:
454                         ret=ssl3_get_client_key_exchange(s);
455                         if (ret <= 0) goto end;
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
477                         s->state=SSL3_ST_SR_FINISHED_A;
478                         s->init_num=0;
479                         break;
480
481                 case SSL3_ST_SR_FINISHED_A:
482                 case SSL3_ST_SR_FINISHED_B:
483                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
484                                 SSL3_ST_SR_FINISHED_B);
485                         if (ret <= 0) goto end;
486                         if (s->hit)
487                                 s->state=SSL_ST_OK;
488                         else
489                                 s->state=SSL3_ST_SW_CHANGE_A;
490                         s->init_num=0;
491                         break;
492
493                 case SSL3_ST_SW_CHANGE_A:
494                 case SSL3_ST_SW_CHANGE_B:
495
496                         s->session->cipher=s->s3->tmp.new_cipher;
497                         if (!s->method->ssl3_enc->setup_key_block(s))
498                                 { ret= -1; goto end; }
499
500                         ret=dtls1_send_change_cipher_spec(s,
501                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
502
503                         if (ret <= 0) goto end;
504                         s->state=SSL3_ST_SW_FINISHED_A;
505                         s->init_num=0;
506
507                         if (!s->method->ssl3_enc->change_cipher_state(s,
508                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
509                                 {
510                                 ret= -1;
511                                 goto end;
512                                 }
513
514                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
515                         break;
516
517                 case SSL3_ST_SW_FINISHED_A:
518                 case SSL3_ST_SW_FINISHED_B:
519                         ret=dtls1_send_finished(s,
520                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
521                                 s->method->ssl3_enc->server_finished_label,
522                                 s->method->ssl3_enc->server_finished_label_len);
523                         if (ret <= 0) goto end;
524                         s->state=SSL3_ST_SW_FLUSH;
525                         if (s->hit)
526                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
527                         else
528                                 s->s3->tmp.next_state=SSL_ST_OK;
529                         s->init_num=0;
530                         break;
531
532                 case SSL_ST_OK:
533                         /* clean a few things up */
534                         ssl3_cleanup_key_block(s);
535
536 #if 0
537                         BUF_MEM_free(s->init_buf);
538                         s->init_buf=NULL;
539 #endif
540
541                         /* remove buffering on output */
542                         ssl_free_wbio_buffer(s);
543
544                         s->init_num=0;
545
546                         if (s->new_session == 2) /* skipped if we just sent a HelloRequest */
547                                 {
548                                 /* actually not necessarily a 'new' session unless
549                                  * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
550                                 
551                                 s->new_session=0;
552                                 
553                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
554                                 
555                                 s->ctx->stats.sess_accept_good++;
556                                 /* s->server=1; */
557                                 s->handshake_func=dtls1_accept;
558
559                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
560                                 }
561                         
562                         ret = 1;
563
564                         /* done handshaking, next message is client hello */
565                         s->d1->handshake_read_seq = 0;
566                         /* next message is server hello */
567                         s->d1->handshake_write_seq = 0;
568                         goto end;
569                         /* break; */
570
571                 default:
572                         SSLerr(SSL_F_SSL3_ACCEPT,SSL_R_UNKNOWN_STATE);
573                         ret= -1;
574                         goto end;
575                         /* break; */
576                         }
577                 
578                 if (!s->s3->tmp.reuse_message && !skip)
579                         {
580                         if (s->debug)
581                                 {
582                                 if ((ret=BIO_flush(s->wbio)) <= 0)
583                                         goto end;
584                                 }
585
586
587                         if ((cb != NULL) && (s->state != state))
588                                 {
589                                 new_state=s->state;
590                                 s->state=state;
591                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
592                                 s->state=new_state;
593                                 }
594                         }
595                 skip=0;
596                 }
597 end:
598         /* BIO_flush(s->wbio); */
599
600         s->in_handshake--;
601         if (cb != NULL)
602                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
603         return(ret);
604         }
605
606 int dtls1_send_hello_request(SSL *s)
607         {
608         unsigned char *p;
609
610         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
611                 {
612                 p=(unsigned char *)s->init_buf->data;
613                 p = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);
614
615                 s->state=SSL3_ST_SW_HELLO_REQ_B;
616                 /* number of bytes to write */
617                 s->init_num=DTLS1_HM_HEADER_LENGTH;
618                 s->init_off=0;
619
620                 /* no need to buffer this message, since there are no retransmit 
621                  * requests for it */
622                 }
623
624         /* SSL3_ST_SW_HELLO_REQ_B */
625         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
626         }
627
628 int dtls1_send_hello_verify_request(SSL *s)
629         {
630         unsigned int msg_len;
631         unsigned char *msg, *buf, *p;
632
633         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
634                 {
635                 buf = (unsigned char *)s->init_buf->data;
636
637                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
638                 *(p++) = s->version >> 8;
639                 *(p++) = s->version & 0xFF;
640
641                 *(p++) = (unsigned char) s->d1->cookie_len;
642         if ( s->ctx->app_gen_cookie_cb != NULL &&
643             s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 
644                 &(s->d1->cookie_len)) == 0)
645             {
646                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
647             return 0;
648             }
649         /* else the cookie is assumed to have 
650          * been initialized by the application */
651
652                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
653                 p += s->d1->cookie_len;
654                 msg_len = p - msg;
655
656                 dtls1_set_message_header(s, buf,
657                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
658
659                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
660                 /* number of bytes to write */
661                 s->init_num=p-buf;
662                 s->init_off=0;
663
664                 /* buffer the message to handle re-xmits */
665                 dtls1_buffer_message(s, 0);
666                 }
667
668         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
669         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
670         }
671
672 int dtls1_send_server_hello(SSL *s)
673         {
674         unsigned char *buf;
675         unsigned char *p,*d;
676         int i,sl;
677         unsigned long l,Time;
678
679         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
680                 {
681                 buf=(unsigned char *)s->init_buf->data;
682                 p=s->s3->server_random;
683                 Time=time(NULL);                        /* Time */
684                 l2n(Time,p);
685                 RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));
686                 /* Do the message type and length last */
687                 d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);
688
689                 *(p++)=s->version>>8;
690                 *(p++)=s->version&0xff;
691
692                 /* Random stuff */
693                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
694                 p+=SSL3_RANDOM_SIZE;
695
696                 /* now in theory we have 3 options to sending back the
697                  * session id.  If it is a re-use, we send back the
698                  * old session-id, if it is a new session, we send
699                  * back the new session-id or we send back a 0 length
700                  * session-id if we want it to be single use.
701                  * Currently I will not implement the '0' length session-id
702                  * 12-Jan-98 - I'll now support the '0' length stuff.
703                  */
704                 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
705                         s->session->session_id_length=0;
706
707                 sl=s->session->session_id_length;
708                 if (sl > sizeof s->session->session_id)
709                         {
710                         SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
711                         return -1;
712                         }
713                 *(p++)=sl;
714                 memcpy(p,s->session->session_id,sl);
715                 p+=sl;
716
717                 /* put the cipher */
718                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
719                 p+=i;
720
721                 /* put the compression method */
722                 if (s->s3->tmp.new_compression == NULL)
723                         *(p++)=0;
724                 else
725                         *(p++)=s->s3->tmp.new_compression->id;
726
727                 /* do the header */
728                 l=(p-d);
729                 d=buf;
730
731                 d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);
732
733                 s->state=SSL3_ST_CW_CLNT_HELLO_B;
734                 /* number of bytes to write */
735                 s->init_num=p-buf;
736                 s->init_off=0;
737
738                 /* buffer the message to handle re-xmits */
739                 dtls1_buffer_message(s, 0);
740                 }
741
742         /* SSL3_ST_CW_CLNT_HELLO_B */
743         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
744         }
745
746 int dtls1_send_server_done(SSL *s)
747         {
748         unsigned char *p;
749
750         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
751                 {
752                 p=(unsigned char *)s->init_buf->data;
753
754                 /* do the header */
755                 p = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);
756
757                 s->state=SSL3_ST_SW_SRVR_DONE_B;
758                 /* number of bytes to write */
759                 s->init_num=DTLS1_HM_HEADER_LENGTH;
760                 s->init_off=0;
761
762                 /* buffer the message to handle re-xmits */
763                 dtls1_buffer_message(s, 0);
764                 }
765
766         /* SSL3_ST_CW_CLNT_HELLO_B */
767         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
768         }
769
770 int dtls1_send_server_key_exchange(SSL *s)
771         {
772 #ifndef OPENSSL_NO_RSA
773         unsigned char *q;
774         int j,num;
775         RSA *rsa;
776         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
777         unsigned int u;
778 #endif
779 #ifndef OPENSSL_NO_DH
780         DH *dh=NULL,*dhp;
781 #endif
782         EVP_PKEY *pkey;
783         unsigned char *p,*d;
784         int al,i;
785         unsigned long type;
786         int n;
787         CERT *cert;
788         BIGNUM *r[4];
789         int nr[4],kn;
790         BUF_MEM *buf;
791         EVP_MD_CTX md_ctx;
792
793         EVP_MD_CTX_init(&md_ctx);
794         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
795                 {
796                 type=s->s3->tmp.new_cipher->algorithms & SSL_MKEY_MASK;
797                 cert=s->cert;
798
799                 buf=s->init_buf;
800
801                 r[0]=r[1]=r[2]=r[3]=NULL;
802                 n=0;
803 #ifndef OPENSSL_NO_RSA
804                 if (type & SSL_kRSA)
805                         {
806                         rsa=cert->rsa_tmp;
807                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
808                                 {
809                                 rsa=s->cert->rsa_tmp_cb(s,
810                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
811                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
812                                 if(rsa == NULL)
813                                 {
814                                         al=SSL_AD_HANDSHAKE_FAILURE;
815                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
816                                         goto f_err;
817                                 }
818                                 RSA_up_ref(rsa);
819                                 cert->rsa_tmp=rsa;
820                                 }
821                         if (rsa == NULL)
822                                 {
823                                 al=SSL_AD_HANDSHAKE_FAILURE;
824                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
825                                 goto f_err;
826                                 }
827                         r[0]=rsa->n;
828                         r[1]=rsa->e;
829                         s->s3->tmp.use_rsa_tmp=1;
830                         }
831                 else
832 #endif
833 #ifndef OPENSSL_NO_DH
834                         if (type & SSL_kEDH)
835                         {
836                         dhp=cert->dh_tmp;
837                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
838                                 dhp=s->cert->dh_tmp_cb(s,
839                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
840                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
841                         if (dhp == NULL)
842                                 {
843                                 al=SSL_AD_HANDSHAKE_FAILURE;
844                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
845                                 goto f_err;
846                                 }
847
848                         if (s->s3->tmp.dh != NULL)
849                                 {
850                                 DH_free(dh);
851                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
852                                 goto err;
853                                 }
854
855                         if ((dh=DHparams_dup(dhp)) == NULL)
856                                 {
857                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
858                                 goto err;
859                                 }
860
861                         s->s3->tmp.dh=dh;
862                         if ((dhp->pub_key == NULL ||
863                              dhp->priv_key == NULL ||
864                              (s->options & SSL_OP_SINGLE_DH_USE)))
865                                 {
866                                 if(!DH_generate_key(dh))
867                                     {
868                                     SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
869                                            ERR_R_DH_LIB);
870                                     goto err;
871                                     }
872                                 }
873                         else
874                                 {
875                                 dh->pub_key=BN_dup(dhp->pub_key);
876                                 dh->priv_key=BN_dup(dhp->priv_key);
877                                 if ((dh->pub_key == NULL) ||
878                                         (dh->priv_key == NULL))
879                                         {
880                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
881                                         goto err;
882                                         }
883                                 }
884                         r[0]=dh->p;
885                         r[1]=dh->g;
886                         r[2]=dh->pub_key;
887                         }
888                 else 
889 #endif
890                         {
891                         al=SSL_AD_HANDSHAKE_FAILURE;
892                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
893                         goto f_err;
894                         }
895                 for (i=0; r[i] != NULL; i++)
896                         {
897                         nr[i]=BN_num_bytes(r[i]);
898                         n+=2+nr[i];
899                         }
900
901                 if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
902                         {
903                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
904                                 == NULL)
905                                 {
906                                 al=SSL_AD_DECODE_ERROR;
907                                 goto f_err;
908                                 }
909                         kn=EVP_PKEY_size(pkey);
910                         }
911                 else
912                         {
913                         pkey=NULL;
914                         kn=0;
915                         }
916
917                 if (!BUF_MEM_grow_clean(buf,n+DTLS1_HM_HEADER_LENGTH+kn))
918                         {
919                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
920                         goto err;
921                         }
922                 d=(unsigned char *)s->init_buf->data;
923                 p= &(d[DTLS1_HM_HEADER_LENGTH]);
924
925                 for (i=0; r[i] != NULL; i++)
926                         {
927                         s2n(nr[i],p);
928                         BN_bn2bin(r[i],p);
929                         p+=nr[i];
930                         }
931
932                 /* not anonymous */
933                 if (pkey != NULL)
934                         {
935                         /* n is the length of the params, they start at
936                          * &(d[DTLS1_HM_HEADER_LENGTH]) and p points to the space
937                          * at the end. */
938 #ifndef OPENSSL_NO_RSA
939                         if (pkey->type == EVP_PKEY_RSA)
940                                 {
941                                 q=md_buf;
942                                 j=0;
943                                 for (num=2; num > 0; num--)
944                                         {
945                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
946                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
947                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
948                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
949                                         EVP_DigestUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
950                                         EVP_DigestFinal_ex(&md_ctx,q,
951                                                 (unsigned int *)&i);
952                                         q+=i;
953                                         j+=i;
954                                         }
955                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
956                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
957                                         {
958                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
959                                         goto err;
960                                         }
961                                 s2n(u,p);
962                                 n+=u+2;
963                                 }
964                         else
965 #endif
966 #if !defined(OPENSSL_NO_DSA)
967                                 if (pkey->type == EVP_PKEY_DSA)
968                                 {
969                                 /* lets do DSS */
970                                 EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
971                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
972                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
973                                 EVP_SignUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
974                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
975                                         (unsigned int *)&i,pkey))
976                                         {
977                                         SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
978                                         goto err;
979                                         }
980                                 s2n(i,p);
981                                 n+=i+2;
982                                 }
983                         else
984 #endif
985                                 {
986                                 /* Is this error check actually needed? */
987                                 al=SSL_AD_HANDSHAKE_FAILURE;
988                                 SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
989                                 goto f_err;
990                                 }
991                         }
992
993                 d = dtls1_set_message_header(s, d,
994                         SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);
995
996                 /* we should now have things packed up, so lets send
997                  * it off */
998                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
999                 s->init_off=0;
1000
1001                 /* buffer the message to handle re-xmits */
1002                 dtls1_buffer_message(s, 0);
1003                 }
1004
1005         s->state = SSL3_ST_SW_KEY_EXCH_B;
1006         EVP_MD_CTX_cleanup(&md_ctx);
1007         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1008 f_err:
1009         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1010 err:
1011         EVP_MD_CTX_cleanup(&md_ctx);
1012         return(-1);
1013         }
1014
1015 int dtls1_send_certificate_request(SSL *s)
1016         {
1017         unsigned char *p,*d;
1018         int i,j,nl,off,n;
1019         STACK_OF(X509_NAME) *sk=NULL;
1020         X509_NAME *name;
1021         BUF_MEM *buf;
1022
1023         if (s->state == SSL3_ST_SW_CERT_REQ_A)
1024                 {
1025                 buf=s->init_buf;
1026
1027                 d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
1028
1029                 /* get the list of acceptable cert types */
1030                 p++;
1031                 n=ssl3_get_req_cert_type(s,p);
1032                 d[0]=n;
1033                 p+=n;
1034                 n++;
1035
1036                 off=n;
1037                 p+=2;
1038                 n+=2;
1039
1040                 sk=SSL_get_client_CA_list(s);
1041                 nl=0;
1042                 if (sk != NULL)
1043                         {
1044                         for (i=0; i<sk_X509_NAME_num(sk); i++)
1045                                 {
1046                                 name=sk_X509_NAME_value(sk,i);
1047                                 j=i2d_X509_NAME(name,NULL);
1048                                 if (!BUF_MEM_grow_clean(buf,DTLS1_HM_HEADER_LENGTH+n+j+2))
1049                                         {
1050                                         SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
1051                                         goto err;
1052                                         }
1053                                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+n]);
1054                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
1055                                         {
1056                                         s2n(j,p);
1057                                         i2d_X509_NAME(name,&p);
1058                                         n+=2+j;
1059                                         nl+=2+j;
1060                                         }
1061                                 else
1062                                         {
1063                                         d=p;
1064                                         i2d_X509_NAME(name,&p);
1065                                         j-=2; s2n(j,d); j+=2;
1066                                         n+=j;
1067                                         nl+=j;
1068                                         }
1069                                 }
1070                         }
1071                 /* else no CA names */
1072                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+off]);
1073                 s2n(nl,p);
1074
1075                 d=(unsigned char *)buf->data;
1076                 *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
1077                 l2n3(n,d);
1078                 l2n(s->d1->handshake_write_seq,d);
1079                 s->d1->handshake_write_seq++;
1080
1081                 /* we should now have things packed up, so lets send
1082                  * it off */
1083
1084                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1085                 s->init_off=0;
1086 #ifdef NETSCAPE_HANG_BUG
1087 /* XXX: what to do about this? */
1088                 p=(unsigned char *)s->init_buf->data + s->init_num;
1089
1090                 /* do the header */
1091                 *(p++)=SSL3_MT_SERVER_DONE;
1092                 *(p++)=0;
1093                 *(p++)=0;
1094                 *(p++)=0;
1095                 s->init_num += 4;
1096 #endif
1097
1098                 /* XDTLS:  set message header ? */
1099                 /* buffer the message to handle re-xmits */
1100                 dtls1_buffer_message(s, 0);
1101
1102                 s->state = SSL3_ST_SW_CERT_REQ_B;
1103                 }
1104
1105         /* SSL3_ST_SW_CERT_REQ_B */
1106         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1107 err:
1108         return(-1);
1109         }
1110
1111 int dtls1_send_server_certificate(SSL *s)
1112         {
1113         unsigned long l;
1114         X509 *x;
1115
1116         if (s->state == SSL3_ST_SW_CERT_A)
1117                 {
1118                 x=ssl_get_server_send_cert(s);
1119                 if (x == NULL &&
1120                         /* VRS: allow null cert if auth == KRB5 */
1121                         (s->s3->tmp.new_cipher->algorithms
1122                                 & (SSL_MKEY_MASK|SSL_AUTH_MASK))
1123                         != (SSL_aKRB5|SSL_kKRB5))
1124                         {
1125                         SSLerr(SSL_F_SSL3_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
1126                         return(0);
1127                         }
1128
1129                 l=dtls1_output_cert_chain(s,x);
1130                 s->state=SSL3_ST_SW_CERT_B;
1131                 s->init_num=(int)l;
1132                 s->init_off=0;
1133
1134                 /* buffer the message to handle re-xmits */
1135                 dtls1_buffer_message(s, 0);
1136                 }
1137
1138         /* SSL3_ST_SW_CERT_B */
1139         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1140         }