1ded18df507d9db886232ed583b9cb26bcf31669
[openssl.git] / ssl / d1_srvr.c
1 /* ssl/d1_srvr.c */
2 /* 
3  * DTLS implementation written by Nagendra Modadugu
4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  
5  */
6 /* ====================================================================
7  * Copyright (c) 1999-2007 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer. 
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    openssl-core@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
57  *
58  */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60  * All rights reserved.
61  *
62  * This package is an SSL implementation written
63  * by Eric Young (eay@cryptsoft.com).
64  * The implementation was written so as to conform with Netscapes SSL.
65  * 
66  * This library is free for commercial and non-commercial use as long as
67  * the following conditions are aheared to.  The following conditions
68  * apply to all code found in this distribution, be it the RC4, RSA,
69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
70  * included with this distribution is covered by the same copyright terms
71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72  * 
73  * Copyright remains Eric Young's, and as such any Copyright notices in
74  * the code are not to be removed.
75  * If this package is used in a product, Eric Young should be given attribution
76  * as the author of the parts of the library used.
77  * This can be in the form of a textual message at program startup or
78  * in documentation (online or textual) provided with the package.
79  * 
80  * Redistribution and use in source and binary forms, with or without
81  * modification, are permitted provided that the following conditions
82  * are met:
83  * 1. Redistributions of source code must retain the copyright
84  *    notice, this list of conditions and the following disclaimer.
85  * 2. Redistributions in binary form must reproduce the above copyright
86  *    notice, this list of conditions and the following disclaimer in the
87  *    documentation and/or other materials provided with the distribution.
88  * 3. All advertising materials mentioning features or use of this software
89  *    must display the following acknowledgement:
90  *    "This product includes cryptographic software written by
91  *     Eric Young (eay@cryptsoft.com)"
92  *    The word 'cryptographic' can be left out if the rouines from the library
93  *    being used are not cryptographic related :-).
94  * 4. If you include any Windows specific code (or a derivative thereof) from 
95  *    the apps directory (application code) you must include an acknowledgement:
96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97  * 
98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108  * SUCH DAMAGE.
109  * 
110  * The licence and distribution terms for any publically available version or
111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
112  * copied and put under another distribution licence
113  * [including the GNU Public Licence.]
114  */
115
116 #include <stdio.h>
117 #include "ssl_locl.h"
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120 #include <openssl/objects.h>
121 #include <openssl/evp.h>
122 #include <openssl/x509.h>
123 #include <openssl/md5.h>
124 #include <openssl/bn.h>
125 #ifndef OPENSSL_NO_DH
126 #include <openssl/dh.h>
127 #endif
128
129 static const SSL_METHOD *dtls1_get_server_method(int ver);
130 static int dtls1_send_hello_verify_request(SSL *s);
131
132 static const SSL_METHOD *dtls1_get_server_method(int ver)
133         {
134         if (ver == DTLS1_VERSION)
135                 return(DTLSv1_server_method());
136         else
137                 return(NULL);
138         }
139
140 IMPLEMENT_dtls1_meth_func(DTLSv1_server_method,
141                         dtls1_accept,
142                         ssl_undefined_function,
143                         dtls1_get_server_method)
144
145 int dtls1_accept(SSL *s)
146         {
147         BUF_MEM *buf;
148         unsigned long Time=(unsigned long)time(NULL);
149         void (*cb)(const SSL *ssl,int type,int val)=NULL;
150         long num1;
151         unsigned long alg_k;
152         int ret= -1;
153         int new_state,state,skip=0;
154
155         RAND_add(&Time,sizeof(Time),0);
156         ERR_clear_error();
157         clear_sys_error();
158
159         if (s->info_callback != NULL)
160                 cb=s->info_callback;
161         else if (s->ctx->info_callback != NULL)
162                 cb=s->ctx->info_callback;
163
164         /* init things to blank */
165         s->in_handshake++;
166         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
167
168         if (s->cert == NULL)
169                 {
170                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
171                 return(-1);
172                 }
173
174         for (;;)
175                 {
176                 state=s->state;
177
178                 switch (s->state)
179                         {
180                 case SSL_ST_RENEGOTIATE:
181                         s->new_session=1;
182                         /* s->state=SSL_ST_ACCEPT; */
183
184                 case SSL_ST_BEFORE:
185                 case SSL_ST_ACCEPT:
186                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
187                 case SSL_ST_OK|SSL_ST_ACCEPT:
188
189                         s->server=1;
190                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
191
192                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
193                                 {
194                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
195                                 return -1;
196                                 }
197                         s->type=SSL_ST_ACCEPT;
198
199                         if (s->init_buf == NULL)
200                                 {
201                                 if ((buf=BUF_MEM_new()) == NULL)
202                                         {
203                                         ret= -1;
204                                         goto end;
205                                         }
206                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
207                                         {
208                                         ret= -1;
209                                         goto end;
210                                         }
211                                 s->init_buf=buf;
212                                 }
213
214                         if (!ssl3_setup_buffers(s))
215                                 {
216                                 ret= -1;
217                                 goto end;
218                                 }
219
220                         s->init_num=0;
221
222                         if (s->state != SSL_ST_RENEGOTIATE)
223                                 {
224                                 /* Ok, we now need to push on a buffering BIO so that
225                                  * the output is sent in a way that TCP likes :-)
226                                  */
227                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
228
229                                 ssl3_init_finished_mac(s);
230                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
231                                 s->ctx->stats.sess_accept++;
232                                 }
233                         else
234                                 {
235                                 /* s->state == SSL_ST_RENEGOTIATE,
236                                  * we will just send a HelloRequest */
237                                 s->ctx->stats.sess_accept_renegotiate++;
238                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
239                                 }
240
241                         if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
242                                 s->d1->send_cookie = 1;
243                         else
244                                 s->d1->send_cookie = 0;
245                         
246                         break;
247
248                 case SSL3_ST_SW_HELLO_REQ_A:
249                 case SSL3_ST_SW_HELLO_REQ_B:
250
251                         s->shutdown=0;
252                         ret=dtls1_send_hello_request(s);
253                         if (ret <= 0) goto end;
254                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
255                         s->state=SSL3_ST_SW_FLUSH;
256                         s->init_num=0;
257
258                         ssl3_init_finished_mac(s);
259                         break;
260
261                 case SSL3_ST_SW_HELLO_REQ_C:
262                         s->state=SSL_ST_OK;
263                         break;
264
265                 case SSL3_ST_SR_CLNT_HELLO_A:
266                 case SSL3_ST_SR_CLNT_HELLO_B:
267                 case SSL3_ST_SR_CLNT_HELLO_C:
268
269                         s->shutdown=0;
270                         ret=ssl3_get_client_hello(s);
271                         if (ret <= 0) goto end;
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                         ret = dtls1_send_hello_verify_request(s);
286                         if ( ret <= 0) goto end;
287                         s->d1->send_cookie = 0;
288                         s->state=SSL3_ST_SW_FLUSH;
289                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
290
291                         /* HelloVerifyRequest resets Finished MAC */
292                         ssl3_init_finished_mac(s);
293                         break;
294                         
295                 case SSL3_ST_SW_SRVR_HELLO_A:
296                 case SSL3_ST_SW_SRVR_HELLO_B:
297                         ret=dtls1_send_server_hello(s);
298                         if (ret <= 0) goto end;
299
300                         if (s->hit)
301                                 s->state=SSL3_ST_SW_CHANGE_A;
302                         else
303                                 s->state=SSL3_ST_SW_CERT_A;
304                         s->init_num=0;
305                         break;
306
307                 case SSL3_ST_SW_CERT_A:
308                 case SSL3_ST_SW_CERT_B:
309                         /* Check if it is anon DH */
310                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL))
311                                 {
312                                 ret=dtls1_send_server_certificate(s);
313                                 if (ret <= 0) goto end;
314                                 }
315                         else
316                                 skip=1;
317                         s->state=SSL3_ST_SW_KEY_EXCH_A;
318                         s->init_num=0;
319                         break;
320
321                 case SSL3_ST_SW_KEY_EXCH_A:
322                 case SSL3_ST_SW_KEY_EXCH_B:
323                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
324
325                         /* clear this, it may get reset by
326                          * send_server_key_exchange */
327                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
328 #ifndef OPENSSL_NO_KRB5
329                                 && !(alg_k & SSL_kKRB5)
330 #endif /* OPENSSL_NO_KRB5 */
331                                 )
332                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
333                                  * even when forbidden by protocol specs
334                                  * (handshake may fail as clients are not required to
335                                  * be able to handle this) */
336                                 s->s3->tmp.use_rsa_tmp=1;
337                         else
338                                 s->s3->tmp.use_rsa_tmp=0;
339
340                         /* only send if a DH key exchange or
341                          * RSA but we have a sign only certificate */
342                         if (s->s3->tmp.use_rsa_tmp
343                             || (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
344                             || ((alg_k & SSL_kRSA)
345                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
346                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
347                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
348                                         )
349                                     )
350                                 )
351                             )
352                                 {
353                                 ret=dtls1_send_server_key_exchange(s);
354                                 if (ret <= 0) goto end;
355                                 }
356                         else
357                                 skip=1;
358
359                         s->state=SSL3_ST_SW_CERT_REQ_A;
360                         s->init_num=0;
361                         break;
362
363                 case SSL3_ST_SW_CERT_REQ_A:
364                 case SSL3_ST_SW_CERT_REQ_B:
365                         if (/* don't request cert unless asked for it: */
366                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
367                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
368                                  * don't request cert during re-negotiation: */
369                                 ((s->session->peer != NULL) &&
370                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
371                                 /* never request cert in anonymous ciphersuites
372                                  * (see section "Certificate request" in SSL 3 drafts
373                                  * and in RFC 2246): */
374                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
375                                  /* ... except when the application insists on verification
376                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
377                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
378                                  /* never request cert in Kerberos ciphersuites */
379                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5))
380                                 {
381                                 /* no cert request */
382                                 skip=1;
383                                 s->s3->tmp.cert_request=0;
384                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
385                                 }
386                         else
387                                 {
388                                 s->s3->tmp.cert_request=1;
389                                 ret=dtls1_send_certificate_request(s);
390                                 if (ret <= 0) goto end;
391 #ifndef NETSCAPE_HANG_BUG
392                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
393 #else
394                                 s->state=SSL3_ST_SW_FLUSH;
395                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
396 #endif
397                                 s->init_num=0;
398                                 }
399                         break;
400
401                 case SSL3_ST_SW_SRVR_DONE_A:
402                 case SSL3_ST_SW_SRVR_DONE_B:
403                         ret=dtls1_send_server_done(s);
404                         if (ret <= 0) goto end;
405                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
406                         s->state=SSL3_ST_SW_FLUSH;
407                         s->init_num=0;
408                         break;
409                 
410                 case SSL3_ST_SW_FLUSH:
411                         /* number of bytes to be flushed */
412                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
413                         if (num1 > 0)
414                                 {
415                                 s->rwstate=SSL_WRITING;
416                                 num1=BIO_flush(s->wbio);
417                                 if (num1 <= 0) { ret= -1; goto end; }
418                                 s->rwstate=SSL_NOTHING;
419                                 }
420
421                         s->state=s->s3->tmp.next_state;
422                         break;
423
424                 case SSL3_ST_SR_CERT_A:
425                 case SSL3_ST_SR_CERT_B:
426                         /* Check for second client hello (MS SGC) */
427                         ret = ssl3_check_client_hello(s);
428                         if (ret <= 0)
429                                 goto end;
430                         if (ret == 2)
431                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
432                         else {
433                                 /* could be sent for a DH cert, even if we
434                                  * have not asked for it :-) */
435                                 ret=ssl3_get_client_certificate(s);
436                                 if (ret <= 0) goto end;
437                                 s->init_num=0;
438                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
439                         }
440                         break;
441
442                 case SSL3_ST_SR_KEY_EXCH_A:
443                 case SSL3_ST_SR_KEY_EXCH_B:
444                         ret=ssl3_get_client_key_exchange(s);
445                         if (ret <= 0) goto end;
446                         s->state=SSL3_ST_SR_CERT_VRFY_A;
447                         s->init_num=0;
448
449                         /* We need to get hashes here so if there is
450                          * a client cert, it can be verified */ 
451                         s->method->ssl3_enc->cert_verify_mac(s,
452                                 NID_md5,
453                                 &(s->s3->tmp.cert_verify_md[0]));
454                         s->method->ssl3_enc->cert_verify_mac(s,
455                                 NID_sha1,
456                                 &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
457
458                         break;
459
460                 case SSL3_ST_SR_CERT_VRFY_A:
461                 case SSL3_ST_SR_CERT_VRFY_B:
462
463                         /* we should decide if we expected this one */
464                         ret=ssl3_get_cert_verify(s);
465                         if (ret <= 0) goto end;
466
467                         s->state=SSL3_ST_SR_FINISHED_A;
468                         s->init_num=0;
469                         break;
470
471                 case SSL3_ST_SR_FINISHED_A:
472                 case SSL3_ST_SR_FINISHED_B:
473                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
474                                 SSL3_ST_SR_FINISHED_B);
475                         if (ret <= 0) goto end;
476                         if (s->hit)
477                                 s->state=SSL_ST_OK;
478                         else
479                                 s->state=SSL3_ST_SW_CHANGE_A;
480                         s->init_num=0;
481                         break;
482
483                 case SSL3_ST_SW_CHANGE_A:
484                 case SSL3_ST_SW_CHANGE_B:
485
486                         s->session->cipher=s->s3->tmp.new_cipher;
487                         if (!s->method->ssl3_enc->setup_key_block(s))
488                                 { ret= -1; goto end; }
489
490                         ret=dtls1_send_change_cipher_spec(s,
491                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
492
493                         if (ret <= 0) goto end;
494                         s->state=SSL3_ST_SW_FINISHED_A;
495                         s->init_num=0;
496
497                         if (!s->method->ssl3_enc->change_cipher_state(s,
498                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
499                                 {
500                                 ret= -1;
501                                 goto end;
502                                 }
503
504                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
505                         break;
506
507                 case SSL3_ST_SW_FINISHED_A:
508                 case SSL3_ST_SW_FINISHED_B:
509                         ret=dtls1_send_finished(s,
510                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
511                                 s->method->ssl3_enc->server_finished_label,
512                                 s->method->ssl3_enc->server_finished_label_len);
513                         if (ret <= 0) goto end;
514                         s->state=SSL3_ST_SW_FLUSH;
515                         if (s->hit)
516                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
517                         else
518                                 s->s3->tmp.next_state=SSL_ST_OK;
519                         s->init_num=0;
520                         break;
521
522                 case SSL_ST_OK:
523                         /* clean a few things up */
524                         ssl3_cleanup_key_block(s);
525
526 #if 0
527                         BUF_MEM_free(s->init_buf);
528                         s->init_buf=NULL;
529 #endif
530
531                         /* remove buffering on output */
532                         ssl_free_wbio_buffer(s);
533
534                         s->init_num=0;
535
536                         if (s->new_session == 2) /* skipped if we just sent a HelloRequest */
537                                 {
538                                 /* actually not necessarily a 'new' session unless
539                                  * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
540                                 
541                                 s->new_session=0;
542                                 
543                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
544                                 
545                                 s->ctx->stats.sess_accept_good++;
546                                 /* s->server=1; */
547                                 s->handshake_func=dtls1_accept;
548
549                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
550                                 }
551                         
552                         ret = 1;
553
554                         /* done handshaking, next message is client hello */
555                         s->d1->handshake_read_seq = 0;
556                         /* next message is server hello */
557                         s->d1->handshake_write_seq = 0;
558                         goto end;
559                         /* break; */
560
561                 default:
562                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
563                         ret= -1;
564                         goto end;
565                         /* break; */
566                         }
567                 
568                 if (!s->s3->tmp.reuse_message && !skip)
569                         {
570                         if (s->debug)
571                                 {
572                                 if ((ret=BIO_flush(s->wbio)) <= 0)
573                                         goto end;
574                                 }
575
576
577                         if ((cb != NULL) && (s->state != state))
578                                 {
579                                 new_state=s->state;
580                                 s->state=state;
581                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
582                                 s->state=new_state;
583                                 }
584                         }
585                 skip=0;
586                 }
587 end:
588         /* BIO_flush(s->wbio); */
589
590         s->in_handshake--;
591         if (cb != NULL)
592                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
593         return(ret);
594         }
595
596 int dtls1_send_hello_request(SSL *s)
597         {
598         unsigned char *p;
599
600         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
601                 {
602                 p=(unsigned char *)s->init_buf->data;
603                 p = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);
604
605                 s->state=SSL3_ST_SW_HELLO_REQ_B;
606                 /* number of bytes to write */
607                 s->init_num=DTLS1_HM_HEADER_LENGTH;
608                 s->init_off=0;
609
610                 /* no need to buffer this message, since there are no retransmit 
611                  * requests for it */
612                 }
613
614         /* SSL3_ST_SW_HELLO_REQ_B */
615         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
616         }
617
618 int dtls1_send_hello_verify_request(SSL *s)
619         {
620         unsigned int msg_len;
621         unsigned char *msg, *buf, *p;
622
623         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
624                 {
625                 buf = (unsigned char *)s->init_buf->data;
626
627                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
628                 *(p++) = s->version >> 8;
629                 *(p++) = s->version & 0xFF;
630
631                 if (s->ctx->app_gen_cookie_cb != NULL &&
632                     s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 
633                         &(s->d1->cookie_len)) == 0)
634                         {
635                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
636                         return 0;
637                         }
638                 /* else the cookie is assumed to have 
639                  * been initialized by the application */
640
641                 *(p++) = (unsigned char) s->d1->cookie_len;
642                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
643                 p += s->d1->cookie_len;
644                 msg_len = p - msg;
645
646                 dtls1_set_message_header(s, buf,
647                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
648
649                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
650                 /* number of bytes to write */
651                 s->init_num=p-buf;
652                 s->init_off=0;
653
654                 /* buffer the message to handle re-xmits */
655                 dtls1_buffer_message(s, 0);
656                 }
657
658         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
659         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
660         }
661
662 int dtls1_send_server_hello(SSL *s)
663         {
664         unsigned char *buf;
665         unsigned char *p,*d;
666         int i;
667         unsigned int sl;
668         unsigned long l,Time;
669
670         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
671                 {
672                 buf=(unsigned char *)s->init_buf->data;
673                 p=s->s3->server_random;
674                 Time=(unsigned long)time(NULL);                 /* Time */
675                 l2n(Time,p);
676                 RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));
677                 /* Do the message type and length last */
678                 d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);
679
680                 *(p++)=s->version>>8;
681                 *(p++)=s->version&0xff;
682
683                 /* Random stuff */
684                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
685                 p+=SSL3_RANDOM_SIZE;
686
687                 /* now in theory we have 3 options to sending back the
688                  * session id.  If it is a re-use, we send back the
689                  * old session-id, if it is a new session, we send
690                  * back the new session-id or we send back a 0 length
691                  * session-id if we want it to be single use.
692                  * Currently I will not implement the '0' length session-id
693                  * 12-Jan-98 - I'll now support the '0' length stuff.
694                  */
695                 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
696                         s->session->session_id_length=0;
697
698                 sl=s->session->session_id_length;
699                 if (sl > sizeof s->session->session_id)
700                         {
701                         SSLerr(SSL_F_DTLS1_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
702                         return -1;
703                         }
704                 *(p++)=sl;
705                 memcpy(p,s->session->session_id,sl);
706                 p+=sl;
707
708                 /* put the cipher */
709                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
710                 p+=i;
711
712                 /* put the compression method */
713 #ifdef OPENSSL_NO_COMP
714                 *(p++)=0;
715 #else
716                 if (s->s3->tmp.new_compression == NULL)
717                         *(p++)=0;
718                 else
719                         *(p++)=s->s3->tmp.new_compression->id;
720 #endif
721
722                 /* do the header */
723                 l=(p-d);
724                 d=buf;
725
726                 d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);
727
728                 s->state=SSL3_ST_SW_SRVR_HELLO_B;
729                 /* number of bytes to write */
730                 s->init_num=p-buf;
731                 s->init_off=0;
732
733                 /* buffer the message to handle re-xmits */
734                 dtls1_buffer_message(s, 0);
735                 }
736
737         /* SSL3_ST_SW_SRVR_HELLO_B */
738         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
739         }
740
741 int dtls1_send_server_done(SSL *s)
742         {
743         unsigned char *p;
744
745         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
746                 {
747                 p=(unsigned char *)s->init_buf->data;
748
749                 /* do the header */
750                 p = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);
751
752                 s->state=SSL3_ST_SW_SRVR_DONE_B;
753                 /* number of bytes to write */
754                 s->init_num=DTLS1_HM_HEADER_LENGTH;
755                 s->init_off=0;
756
757                 /* buffer the message to handle re-xmits */
758                 dtls1_buffer_message(s, 0);
759                 }
760
761         /* SSL3_ST_SW_SRVR_DONE_B */
762         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
763         }
764
765 int dtls1_send_server_key_exchange(SSL *s)
766         {
767 #ifndef OPENSSL_NO_RSA
768         unsigned char *q;
769         int j,num;
770         RSA *rsa;
771         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
772         unsigned int u;
773 #endif
774 #ifndef OPENSSL_NO_DH
775         DH *dh=NULL,*dhp;
776 #endif
777         EVP_PKEY *pkey;
778         unsigned char *p,*d;
779         int al,i;
780         unsigned long type;
781         int n;
782         CERT *cert;
783         BIGNUM *r[4];
784         int nr[4],kn;
785         BUF_MEM *buf;
786         EVP_MD_CTX md_ctx;
787
788         EVP_MD_CTX_init(&md_ctx);
789         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
790                 {
791                 type=s->s3->tmp.new_cipher->algorithm_mkey;
792                 cert=s->cert;
793
794                 buf=s->init_buf;
795
796                 r[0]=r[1]=r[2]=r[3]=NULL;
797                 n=0;
798 #ifndef OPENSSL_NO_RSA
799                 if (type & SSL_kRSA)
800                         {
801                         rsa=cert->rsa_tmp;
802                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
803                                 {
804                                 rsa=s->cert->rsa_tmp_cb(s,
805                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
806                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
807                                 if(rsa == NULL)
808                                 {
809                                         al=SSL_AD_HANDSHAKE_FAILURE;
810                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
811                                         goto f_err;
812                                 }
813                                 RSA_up_ref(rsa);
814                                 cert->rsa_tmp=rsa;
815                                 }
816                         if (rsa == NULL)
817                                 {
818                                 al=SSL_AD_HANDSHAKE_FAILURE;
819                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
820                                 goto f_err;
821                                 }
822                         r[0]=rsa->n;
823                         r[1]=rsa->e;
824                         s->s3->tmp.use_rsa_tmp=1;
825                         }
826                 else
827 #endif
828 #ifndef OPENSSL_NO_DH
829                         if (type & SSL_kEDH)
830                         {
831                         dhp=cert->dh_tmp;
832                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
833                                 dhp=s->cert->dh_tmp_cb(s,
834                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
835                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
836                         if (dhp == NULL)
837                                 {
838                                 al=SSL_AD_HANDSHAKE_FAILURE;
839                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
840                                 goto f_err;
841                                 }
842
843                         if (s->s3->tmp.dh != NULL)
844                                 {
845                                 DH_free(dh);
846                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
847                                 goto err;
848                                 }
849
850                         if ((dh=DHparams_dup(dhp)) == NULL)
851                                 {
852                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
853                                 goto err;
854                                 }
855
856                         s->s3->tmp.dh=dh;
857                         if ((dhp->pub_key == NULL ||
858                              dhp->priv_key == NULL ||
859                              (s->options & SSL_OP_SINGLE_DH_USE)))
860                                 {
861                                 if(!DH_generate_key(dh))
862                                     {
863                                     SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,
864                                            ERR_R_DH_LIB);
865                                     goto err;
866                                     }
867                                 }
868                         else
869                                 {
870                                 dh->pub_key=BN_dup(dhp->pub_key);
871                                 dh->priv_key=BN_dup(dhp->priv_key);
872                                 if ((dh->pub_key == NULL) ||
873                                         (dh->priv_key == NULL))
874                                         {
875                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
876                                         goto err;
877                                         }
878                                 }
879                         r[0]=dh->p;
880                         r[1]=dh->g;
881                         r[2]=dh->pub_key;
882                         }
883                 else 
884 #endif
885                         {
886                         al=SSL_AD_HANDSHAKE_FAILURE;
887                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
888                         goto f_err;
889                         }
890                 for (i=0; r[i] != NULL; i++)
891                         {
892                         nr[i]=BN_num_bytes(r[i]);
893                         n+=2+nr[i];
894                         }
895
896                 if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL))
897                         {
898                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
899                                 == NULL)
900                                 {
901                                 al=SSL_AD_DECODE_ERROR;
902                                 goto f_err;
903                                 }
904                         kn=EVP_PKEY_size(pkey);
905                         }
906                 else
907                         {
908                         pkey=NULL;
909                         kn=0;
910                         }
911
912                 if (!BUF_MEM_grow_clean(buf,n+DTLS1_HM_HEADER_LENGTH+kn))
913                         {
914                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
915                         goto err;
916                         }
917                 d=(unsigned char *)s->init_buf->data;
918                 p= &(d[DTLS1_HM_HEADER_LENGTH]);
919
920                 for (i=0; r[i] != NULL; i++)
921                         {
922                         s2n(nr[i],p);
923                         BN_bn2bin(r[i],p);
924                         p+=nr[i];
925                         }
926
927                 /* not anonymous */
928                 if (pkey != NULL)
929                         {
930                         /* n is the length of the params, they start at
931                          * &(d[DTLS1_HM_HEADER_LENGTH]) and p points to the space
932                          * at the end. */
933 #ifndef OPENSSL_NO_RSA
934                         if (pkey->type == EVP_PKEY_RSA)
935                                 {
936                                 q=md_buf;
937                                 j=0;
938                                 for (num=2; num > 0; num--)
939                                         {
940                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
941                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
942                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
943                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
944                                         EVP_DigestUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
945                                         EVP_DigestFinal_ex(&md_ctx,q,
946                                                 (unsigned int *)&i);
947                                         q+=i;
948                                         j+=i;
949                                         }
950                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
951                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
952                                         {
953                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
954                                         goto err;
955                                         }
956                                 s2n(u,p);
957                                 n+=u+2;
958                                 }
959                         else
960 #endif
961 #if !defined(OPENSSL_NO_DSA)
962                                 if (pkey->type == EVP_PKEY_DSA)
963                                 {
964                                 /* lets do DSS */
965                                 EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
966                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
967                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
968                                 EVP_SignUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
969                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
970                                         (unsigned int *)&i,pkey))
971                                         {
972                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
973                                         goto err;
974                                         }
975                                 s2n(i,p);
976                                 n+=i+2;
977                                 }
978                         else
979 #endif
980                                 {
981                                 /* Is this error check actually needed? */
982                                 al=SSL_AD_HANDSHAKE_FAILURE;
983                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
984                                 goto f_err;
985                                 }
986                         }
987
988                 d = dtls1_set_message_header(s, d,
989                         SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);
990
991                 /* we should now have things packed up, so lets send
992                  * it off */
993                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
994                 s->init_off=0;
995
996                 /* buffer the message to handle re-xmits */
997                 dtls1_buffer_message(s, 0);
998                 }
999
1000         s->state = SSL3_ST_SW_KEY_EXCH_B;
1001         EVP_MD_CTX_cleanup(&md_ctx);
1002         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1003 f_err:
1004         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1005 err:
1006         EVP_MD_CTX_cleanup(&md_ctx);
1007         return(-1);
1008         }
1009
1010 int dtls1_send_certificate_request(SSL *s)
1011         {
1012         unsigned char *p,*d;
1013         int i,j,nl,off,n;
1014         STACK_OF(X509_NAME) *sk=NULL;
1015         X509_NAME *name;
1016         BUF_MEM *buf;
1017         unsigned int msg_len;
1018
1019         if (s->state == SSL3_ST_SW_CERT_REQ_A)
1020                 {
1021                 buf=s->init_buf;
1022
1023                 d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
1024
1025                 /* get the list of acceptable cert types */
1026                 p++;
1027                 n=ssl3_get_req_cert_type(s,p);
1028                 d[0]=n;
1029                 p+=n;
1030                 n++;
1031
1032                 off=n;
1033                 p+=2;
1034                 n+=2;
1035
1036                 sk=SSL_get_client_CA_list(s);
1037                 nl=0;
1038                 if (sk != NULL)
1039                         {
1040                         for (i=0; i<sk_X509_NAME_num(sk); i++)
1041                                 {
1042                                 name=sk_X509_NAME_value(sk,i);
1043                                 j=i2d_X509_NAME(name,NULL);
1044                                 if (!BUF_MEM_grow_clean(buf,DTLS1_HM_HEADER_LENGTH+n+j+2))
1045                                         {
1046                                         SSLerr(SSL_F_DTLS1_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
1047                                         goto err;
1048                                         }
1049                                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+n]);
1050                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
1051                                         {
1052                                         s2n(j,p);
1053                                         i2d_X509_NAME(name,&p);
1054                                         n+=2+j;
1055                                         nl+=2+j;
1056                                         }
1057                                 else
1058                                         {
1059                                         d=p;
1060                                         i2d_X509_NAME(name,&p);
1061                                         j-=2; s2n(j,d); j+=2;
1062                                         n+=j;
1063                                         nl+=j;
1064                                         }
1065                                 }
1066                         }
1067                 /* else no CA names */
1068                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+off]);
1069                 s2n(nl,p);
1070
1071                 d=(unsigned char *)buf->data;
1072                 *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
1073                 l2n3(n,d);
1074                 s2n(s->d1->handshake_write_seq,d);
1075                 s->d1->handshake_write_seq++;
1076
1077                 /* we should now have things packed up, so lets send
1078                  * it off */
1079
1080                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1081                 s->init_off=0;
1082 #ifdef NETSCAPE_HANG_BUG
1083 /* XXX: what to do about this? */
1084                 p=(unsigned char *)s->init_buf->data + s->init_num;
1085
1086                 /* do the header */
1087                 *(p++)=SSL3_MT_SERVER_DONE;
1088                 *(p++)=0;
1089                 *(p++)=0;
1090                 *(p++)=0;
1091                 s->init_num += 4;
1092 #endif
1093
1094                 /* XDTLS:  set message header ? */
1095                 msg_len = s->init_num - DTLS1_HM_HEADER_LENGTH;
1096                 dtls1_set_message_header(s, (void *)s->init_buf->data,
1097                         SSL3_MT_CERTIFICATE_REQUEST, msg_len, 0, msg_len);
1098
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                         {
1121                         /* VRS: allow null cert if auth == KRB5 */
1122                         if ((s->s3->tmp.new_cipher->algorithm_mkey != SSL_kKRB5) ||
1123                             (s->s3->tmp.new_cipher->algorithm_auth != SSL_aKRB5))
1124                                 {
1125                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
1126                                 return(0);
1127                                 }
1128                         }
1129
1130                 l=dtls1_output_cert_chain(s,x);
1131                 s->state=SSL3_ST_SW_CERT_B;
1132                 s->init_num=(int)l;
1133                 s->init_off=0;
1134
1135                 /* buffer the message to handle re-xmits */
1136                 dtls1_buffer_message(s, 0);
1137                 }
1138
1139         /* SSL3_ST_SW_CERT_B */
1140         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1141         }