180fc6e646665a7fe9e776203a170d6be71c7b6a
[openssl.git] / ssl / d1_srvr.c
1 /* ssl/d1_srvr.c */
2 /* 
3  * DTLS implementation written by Nagendra Modadugu
4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  
5  */
6 /* ====================================================================
7  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer. 
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    openssl-core@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
57  *
58  */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60  * All rights reserved.
61  *
62  * This package is an SSL implementation written
63  * by Eric Young (eay@cryptsoft.com).
64  * The implementation was written so as to conform with Netscapes SSL.
65  * 
66  * This library is free for commercial and non-commercial use as long as
67  * the following conditions are aheared to.  The following conditions
68  * apply to all code found in this distribution, be it the RC4, RSA,
69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
70  * included with this distribution is covered by the same copyright terms
71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72  * 
73  * Copyright remains Eric Young's, and as such any Copyright notices in
74  * the code are not to be removed.
75  * If this package is used in a product, Eric Young should be given attribution
76  * as the author of the parts of the library used.
77  * This can be in the form of a textual message at program startup or
78  * in documentation (online or textual) provided with the package.
79  * 
80  * Redistribution and use in source and binary forms, with or without
81  * modification, are permitted provided that the following conditions
82  * are met:
83  * 1. Redistributions of source code must retain the copyright
84  *    notice, this list of conditions and the following disclaimer.
85  * 2. Redistributions in binary form must reproduce the above copyright
86  *    notice, this list of conditions and the following disclaimer in the
87  *    documentation and/or other materials provided with the distribution.
88  * 3. All advertising materials mentioning features or use of this software
89  *    must display the following acknowledgement:
90  *    "This product includes cryptographic software written by
91  *     Eric Young (eay@cryptsoft.com)"
92  *    The word 'cryptographic' can be left out if the rouines from the library
93  *    being used are not cryptographic related :-).
94  * 4. If you include any Windows specific code (or a derivative thereof) from 
95  *    the apps directory (application code) you must include an acknowledgement:
96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97  * 
98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108  * SUCH DAMAGE.
109  * 
110  * The licence and distribution terms for any publically available version or
111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
112  * copied and put under another distribution licence
113  * [including the GNU Public Licence.]
114  */
115
116 #include <stdio.h>
117 #include "ssl_locl.h"
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120 #include <openssl/objects.h>
121 #include <openssl/evp.h>
122 #include <openssl/x509.h>
123 #include <openssl/md5.h>
124 #ifndef OPENSSL_NO_DH
125 #include <openssl/dh.h>
126 #endif
127
128 static SSL_METHOD *dtls1_get_server_method(int ver);
129 static int dtls1_send_hello_verify_request(SSL *s);
130
131 static SSL_METHOD *dtls1_get_server_method(int ver)
132         {
133         if (ver == DTLS1_VERSION)
134                 return(DTLSv1_server_method());
135         else
136                 return(NULL);
137         }
138
139 IMPLEMENT_dtls1_meth_func(DTLSv1_server_method,
140                         dtls1_accept,
141                         ssl_undefined_function,
142                         dtls1_get_server_method)
143
144 int dtls1_accept(SSL *s)
145         {
146         BUF_MEM *buf;
147         unsigned long l,Time=time(NULL);
148         void (*cb)(const SSL *ssl,int type,int val)=NULL;
149         long num1;
150         int ret= -1;
151         int new_state,state,skip=0;
152
153         RAND_add(&Time,sizeof(Time),0);
154         ERR_clear_error();
155         clear_sys_error();
156
157         if (s->info_callback != NULL)
158                 cb=s->info_callback;
159         else if (s->ctx->info_callback != NULL)
160                 cb=s->ctx->info_callback;
161
162         /* init things to blank */
163         s->in_handshake++;
164         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
165
166         if (s->cert == NULL)
167                 {
168                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
169                 return(-1);
170                 }
171
172         for (;;)
173                 {
174                 state=s->state;
175
176                 switch (s->state)
177                         {
178                 case SSL_ST_RENEGOTIATE:
179                         s->new_session=1;
180                         /* s->state=SSL_ST_ACCEPT; */
181
182                 case SSL_ST_BEFORE:
183                 case SSL_ST_ACCEPT:
184                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
185                 case SSL_ST_OK|SSL_ST_ACCEPT:
186
187                         s->server=1;
188                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
189
190                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
191                                 {
192                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
193                                 return -1;
194                                 }
195                         s->type=SSL_ST_ACCEPT;
196
197                         if (s->init_buf == NULL)
198                                 {
199                                 if ((buf=BUF_MEM_new()) == NULL)
200                                         {
201                                         ret= -1;
202                                         goto end;
203                                         }
204                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
205                                         {
206                                         ret= -1;
207                                         goto end;
208                                         }
209                                 s->init_buf=buf;
210                                 }
211
212                         if (!ssl3_setup_buffers(s))
213                                 {
214                                 ret= -1;
215                                 goto end;
216                                 }
217
218                         s->init_num=0;
219
220                         if (s->state != SSL_ST_RENEGOTIATE)
221                                 {
222                                 /* Ok, we now need to push on a buffering BIO so that
223                                  * the output is sent in a way that TCP likes :-)
224                                  */
225                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
226
227                                 ssl3_init_finished_mac(s);
228                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
229                                 s->ctx->stats.sess_accept++;
230                                 }
231                         else
232                                 {
233                                 /* s->state == SSL_ST_RENEGOTIATE,
234                                  * we will just send a HelloRequest */
235                                 s->ctx->stats.sess_accept_renegotiate++;
236                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
237                                 }
238
239             if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
240                 s->d1->send_cookie = 1;
241             else
242                 s->d1->send_cookie = 0;
243
244                         break;
245
246                 case SSL3_ST_SW_HELLO_REQ_A:
247                 case SSL3_ST_SW_HELLO_REQ_B:
248
249                         s->shutdown=0;
250                         ret=dtls1_send_hello_request(s);
251                         if (ret <= 0) goto end;
252                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
253                         s->state=SSL3_ST_SW_FLUSH;
254                         s->init_num=0;
255
256                         ssl3_init_finished_mac(s);
257                         break;
258
259                 case SSL3_ST_SW_HELLO_REQ_C:
260                         s->state=SSL_ST_OK;
261                         break;
262
263                 case SSL3_ST_SR_CLNT_HELLO_A:
264                 case SSL3_ST_SR_CLNT_HELLO_B:
265                 case SSL3_ST_SR_CLNT_HELLO_C:
266
267                         s->shutdown=0;
268                         ret=ssl3_get_client_hello(s);
269                         if (ret <= 0) goto end;
270                         s->new_session = 2;
271
272                         if ( s->d1->send_cookie)
273                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
274                         else
275                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
276
277                         s->init_num=0;
278                         break;
279                         
280                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
281                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
282
283                         ret = dtls1_send_hello_verify_request(s);
284                         if ( ret <= 0) goto end;
285                         s->d1->send_cookie = 0;
286                         s->state=SSL3_ST_SW_FLUSH;
287                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
288                         break;
289                         
290                 case SSL3_ST_SW_SRVR_HELLO_A:
291                 case SSL3_ST_SW_SRVR_HELLO_B:
292                         ret=dtls1_send_server_hello(s);
293                         if (ret <= 0) goto end;
294
295                         if (s->hit)
296                                 s->state=SSL3_ST_SW_CHANGE_A;
297                         else
298                                 s->state=SSL3_ST_SW_CERT_A;
299                         s->init_num=0;
300                         break;
301
302                 case SSL3_ST_SW_CERT_A:
303                 case SSL3_ST_SW_CERT_B:
304                         /* Check if it is anon DH */
305                         if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
306                                 {
307                                 ret=dtls1_send_server_certificate(s);
308                                 if (ret <= 0) goto end;
309                                 }
310                         else
311                                 skip=1;
312                         s->state=SSL3_ST_SW_KEY_EXCH_A;
313                         s->init_num=0;
314                         break;
315
316                 case SSL3_ST_SW_KEY_EXCH_A:
317                 case SSL3_ST_SW_KEY_EXCH_B:
318                         l=s->s3->tmp.new_cipher->algorithms;
319
320                         /* clear this, it may get reset by
321                          * send_server_key_exchange */
322                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
323 #ifndef OPENSSL_NO_KRB5
324                                 && !(l & SSL_KRB5)
325 #endif /* OPENSSL_NO_KRB5 */
326                                 )
327                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
328                                  * even when forbidden by protocol specs
329                                  * (handshake may fail as clients are not required to
330                                  * be able to handle this) */
331                                 s->s3->tmp.use_rsa_tmp=1;
332                         else
333                                 s->s3->tmp.use_rsa_tmp=0;
334
335                         /* only send if a DH key exchange, fortezza or
336                          * RSA but we have a sign only certificate */
337                         if (s->s3->tmp.use_rsa_tmp
338                             || (l & (SSL_DH|SSL_kFZA))
339                             || ((l & SSL_kRSA)
340                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
341                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
342                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
343                                         )
344                                     )
345                                 )
346                             )
347                                 {
348                                 ret=dtls1_send_server_key_exchange(s);
349                                 if (ret <= 0) goto end;
350                                 }
351                         else
352                                 skip=1;
353
354                         s->state=SSL3_ST_SW_CERT_REQ_A;
355                         s->init_num=0;
356                         break;
357
358                 case SSL3_ST_SW_CERT_REQ_A:
359                 case SSL3_ST_SW_CERT_REQ_B:
360                         if (/* don't request cert unless asked for it: */
361                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
362                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
363                                  * don't request cert during re-negotiation: */
364                                 ((s->session->peer != NULL) &&
365                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
366                                 /* never request cert in anonymous ciphersuites
367                                  * (see section "Certificate request" in SSL 3 drafts
368                                  * and in RFC 2246): */
369                                 ((s->s3->tmp.new_cipher->algorithms & SSL_aNULL) &&
370                                  /* ... except when the application insists on verification
371                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
372                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
373                                  /* never request cert in Kerberos ciphersuites */
374                                 (s->s3->tmp.new_cipher->algorithms & SSL_aKRB5))
375                                 {
376                                 /* no cert request */
377                                 skip=1;
378                                 s->s3->tmp.cert_request=0;
379                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
380                                 }
381                         else
382                                 {
383                                 s->s3->tmp.cert_request=1;
384                                 ret=dtls1_send_certificate_request(s);
385                                 if (ret <= 0) goto end;
386 #ifndef NETSCAPE_HANG_BUG
387                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
388 #else
389                                 s->state=SSL3_ST_SW_FLUSH;
390                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
391 #endif
392                                 s->init_num=0;
393                                 }
394                         break;
395
396                 case SSL3_ST_SW_SRVR_DONE_A:
397                 case SSL3_ST_SW_SRVR_DONE_B:
398                         ret=dtls1_send_server_done(s);
399                         if (ret <= 0) goto end;
400                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
401                         s->state=SSL3_ST_SW_FLUSH;
402                         s->init_num=0;
403                         break;
404                 
405                 case SSL3_ST_SW_FLUSH:
406                         /* number of bytes to be flushed */
407                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
408                         if (num1 > 0)
409                                 {
410                                 s->rwstate=SSL_WRITING;
411                                 num1=BIO_flush(s->wbio);
412                                 if (num1 <= 0) { ret= -1; goto end; }
413                                 s->rwstate=SSL_NOTHING;
414                                 }
415
416                         s->state=s->s3->tmp.next_state;
417                         break;
418
419                 case SSL3_ST_SR_CERT_A:
420                 case SSL3_ST_SR_CERT_B:
421                         /* Check for second client hello (MS SGC) */
422                         ret = ssl3_check_client_hello(s);
423                         if (ret <= 0)
424                                 goto end;
425                         if (ret == 2)
426                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
427                         else {
428                                 /* could be sent for a DH cert, even if we
429                                  * have not asked for it :-) */
430                                 ret=ssl3_get_client_certificate(s);
431                                 if (ret <= 0) goto end;
432                                 s->init_num=0;
433                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
434                         }
435                         break;
436
437                 case SSL3_ST_SR_KEY_EXCH_A:
438                 case SSL3_ST_SR_KEY_EXCH_B:
439                         ret=ssl3_get_client_key_exchange(s);
440                         if (ret <= 0) goto end;
441                         s->state=SSL3_ST_SR_CERT_VRFY_A;
442                         s->init_num=0;
443
444                         /* We need to get hashes here so if there is
445                          * a client cert, it can be verified */ 
446                         s->method->ssl3_enc->cert_verify_mac(s,
447                                 &(s->s3->finish_dgst1),
448                                 &(s->s3->tmp.cert_verify_md[0]));
449                         s->method->ssl3_enc->cert_verify_mac(s,
450                                 &(s->s3->finish_dgst2),
451                                 &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
452
453                         break;
454
455                 case SSL3_ST_SR_CERT_VRFY_A:
456                 case SSL3_ST_SR_CERT_VRFY_B:
457
458                         /* we should decide if we expected this one */
459                         ret=ssl3_get_cert_verify(s);
460                         if (ret <= 0) goto end;
461
462                         s->state=SSL3_ST_SR_FINISHED_A;
463                         s->init_num=0;
464                         break;
465
466                 case SSL3_ST_SR_FINISHED_A:
467                 case SSL3_ST_SR_FINISHED_B:
468                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
469                                 SSL3_ST_SR_FINISHED_B);
470                         if (ret <= 0) goto end;
471                         if (s->hit)
472                                 s->state=SSL_ST_OK;
473                         else
474                                 s->state=SSL3_ST_SW_CHANGE_A;
475                         s->init_num=0;
476                         break;
477
478                 case SSL3_ST_SW_CHANGE_A:
479                 case SSL3_ST_SW_CHANGE_B:
480
481                         s->session->cipher=s->s3->tmp.new_cipher;
482                         if (!s->method->ssl3_enc->setup_key_block(s))
483                                 { ret= -1; goto end; }
484
485                         ret=dtls1_send_change_cipher_spec(s,
486                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
487
488                         if (ret <= 0) goto end;
489                         s->state=SSL3_ST_SW_FINISHED_A;
490                         s->init_num=0;
491
492                         if (!s->method->ssl3_enc->change_cipher_state(s,
493                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
494                                 {
495                                 ret= -1;
496                                 goto end;
497                                 }
498
499                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
500                         break;
501
502                 case SSL3_ST_SW_FINISHED_A:
503                 case SSL3_ST_SW_FINISHED_B:
504                         ret=dtls1_send_finished(s,
505                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
506                                 s->method->ssl3_enc->server_finished_label,
507                                 s->method->ssl3_enc->server_finished_label_len);
508                         if (ret <= 0) goto end;
509                         s->state=SSL3_ST_SW_FLUSH;
510                         if (s->hit)
511                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
512                         else
513                                 s->s3->tmp.next_state=SSL_ST_OK;
514                         s->init_num=0;
515                         break;
516
517                 case SSL_ST_OK:
518                         /* clean a few things up */
519                         ssl3_cleanup_key_block(s);
520
521 #if 0
522                         BUF_MEM_free(s->init_buf);
523                         s->init_buf=NULL;
524 #endif
525
526                         /* remove buffering on output */
527                         ssl_free_wbio_buffer(s);
528
529                         s->init_num=0;
530
531                         if (s->new_session == 2) /* skipped if we just sent a HelloRequest */
532                                 {
533                                 /* actually not necessarily a 'new' session unless
534                                  * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
535                                 
536                                 s->new_session=0;
537                                 
538                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
539                                 
540                                 s->ctx->stats.sess_accept_good++;
541                                 /* s->server=1; */
542                                 s->handshake_func=dtls1_accept;
543
544                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
545                                 }
546                         
547                         ret = 1;
548
549                         /* done handshaking, next message is client hello */
550                         s->d1->handshake_read_seq = 0;
551                         /* next message is server hello */
552                         s->d1->handshake_write_seq = 0;
553                         goto end;
554                         /* break; */
555
556                 default:
557                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
558                         ret= -1;
559                         goto end;
560                         /* break; */
561                         }
562                 
563                 if (!s->s3->tmp.reuse_message && !skip)
564                         {
565                         if (s->debug)
566                                 {
567                                 if ((ret=BIO_flush(s->wbio)) <= 0)
568                                         goto end;
569                                 }
570
571
572                         if ((cb != NULL) && (s->state != state))
573                                 {
574                                 new_state=s->state;
575                                 s->state=state;
576                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
577                                 s->state=new_state;
578                                 }
579                         }
580                 skip=0;
581                 }
582 end:
583         /* BIO_flush(s->wbio); */
584
585         s->in_handshake--;
586         if (cb != NULL)
587                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
588         return(ret);
589         }
590
591 int dtls1_send_hello_request(SSL *s)
592         {
593         unsigned char *p;
594
595         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
596                 {
597                 p=(unsigned char *)s->init_buf->data;
598                 p = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);
599
600                 s->state=SSL3_ST_SW_HELLO_REQ_B;
601                 /* number of bytes to write */
602                 s->init_num=DTLS1_HM_HEADER_LENGTH;
603                 s->init_off=0;
604
605                 /* no need to buffer this message, since there are no retransmit 
606                  * requests for it */
607                 }
608
609         /* SSL3_ST_SW_HELLO_REQ_B */
610         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
611         }
612
613 int dtls1_send_hello_verify_request(SSL *s)
614         {
615         unsigned int msg_len;
616         unsigned char *msg, *buf, *p;
617
618         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
619                 {
620                 buf = (unsigned char *)s->init_buf->data;
621
622                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
623                 *(p++) = s->version >> 8;
624                 *(p++) = s->version & 0xFF;
625
626                 *(p++) = (unsigned char) s->d1->cookie_len;
627         if ( s->ctx->app_gen_cookie_cb != NULL &&
628             s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 
629                 &(s->d1->cookie_len)) == 0)
630             {
631                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
632             return 0;
633             }
634         /* else the cookie is assumed to have 
635          * been initialized by the application */
636
637                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
638                 p += s->d1->cookie_len;
639                 msg_len = p - msg;
640
641                 dtls1_set_message_header(s, buf,
642                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
643
644                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
645                 /* number of bytes to write */
646                 s->init_num=p-buf;
647                 s->init_off=0;
648
649                 /* buffer the message to handle re-xmits */
650                 dtls1_buffer_message(s, 0);
651                 }
652
653         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
654         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
655         }
656
657 int dtls1_send_server_hello(SSL *s)
658         {
659         unsigned char *buf;
660         unsigned char *p,*d;
661         int i;
662         unsigned int sl;
663         unsigned long l,Time;
664
665         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
666                 {
667                 buf=(unsigned char *)s->init_buf->data;
668                 p=s->s3->server_random;
669                 Time=time(NULL);                        /* Time */
670                 l2n(Time,p);
671                 RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));
672                 /* Do the message type and length last */
673                 d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);
674
675                 *(p++)=s->version>>8;
676                 *(p++)=s->version&0xff;
677
678                 /* Random stuff */
679                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
680                 p+=SSL3_RANDOM_SIZE;
681
682                 /* now in theory we have 3 options to sending back the
683                  * session id.  If it is a re-use, we send back the
684                  * old session-id, if it is a new session, we send
685                  * back the new session-id or we send back a 0 length
686                  * session-id if we want it to be single use.
687                  * Currently I will not implement the '0' length session-id
688                  * 12-Jan-98 - I'll now support the '0' length stuff.
689                  */
690                 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
691                         s->session->session_id_length=0;
692
693                 sl=s->session->session_id_length;
694                 if (sl > sizeof s->session->session_id)
695                         {
696                         SSLerr(SSL_F_DTLS1_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
697                         return -1;
698                         }
699                 *(p++)=sl;
700                 memcpy(p,s->session->session_id,sl);
701                 p+=sl;
702
703                 /* put the cipher */
704                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
705                 p+=i;
706
707                 /* put the compression method */
708 #ifdef OPENSSL_NO_COMP
709                 *(p++)=0;
710 #else
711                 if (s->s3->tmp.new_compression == NULL)
712                         *(p++)=0;
713                 else
714                         *(p++)=s->s3->tmp.new_compression->id;
715 #endif
716
717                 /* do the header */
718                 l=(p-d);
719                 d=buf;
720
721                 d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);
722
723                 s->state=SSL3_ST_CW_CLNT_HELLO_B;
724                 /* number of bytes to write */
725                 s->init_num=p-buf;
726                 s->init_off=0;
727
728                 /* buffer the message to handle re-xmits */
729                 dtls1_buffer_message(s, 0);
730                 }
731
732         /* SSL3_ST_CW_CLNT_HELLO_B */
733         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
734         }
735
736 int dtls1_send_server_done(SSL *s)
737         {
738         unsigned char *p;
739
740         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
741                 {
742                 p=(unsigned char *)s->init_buf->data;
743
744                 /* do the header */
745                 p = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);
746
747                 s->state=SSL3_ST_SW_SRVR_DONE_B;
748                 /* number of bytes to write */
749                 s->init_num=DTLS1_HM_HEADER_LENGTH;
750                 s->init_off=0;
751
752                 /* buffer the message to handle re-xmits */
753                 dtls1_buffer_message(s, 0);
754                 }
755
756         /* SSL3_ST_CW_CLNT_HELLO_B */
757         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
758         }
759
760 int dtls1_send_server_key_exchange(SSL *s)
761         {
762 #ifndef OPENSSL_NO_RSA
763         unsigned char *q;
764         int j,num;
765         RSA *rsa;
766         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
767         unsigned int u;
768 #endif
769 #ifndef OPENSSL_NO_DH
770         DH *dh=NULL,*dhp;
771 #endif
772         EVP_PKEY *pkey;
773         unsigned char *p,*d;
774         int al,i;
775         unsigned long type;
776         int n;
777         CERT *cert;
778         BIGNUM *r[4];
779         int nr[4],kn;
780         BUF_MEM *buf;
781         EVP_MD_CTX md_ctx;
782
783         EVP_MD_CTX_init(&md_ctx);
784         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
785                 {
786                 type=s->s3->tmp.new_cipher->algorithms & SSL_MKEY_MASK;
787                 cert=s->cert;
788
789                 buf=s->init_buf;
790
791                 r[0]=r[1]=r[2]=r[3]=NULL;
792                 n=0;
793 #ifndef OPENSSL_NO_RSA
794                 if (type & SSL_kRSA)
795                         {
796                         rsa=cert->rsa_tmp;
797                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
798                                 {
799                                 rsa=s->cert->rsa_tmp_cb(s,
800                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
801                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
802                                 if(rsa == NULL)
803                                 {
804                                         al=SSL_AD_HANDSHAKE_FAILURE;
805                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
806                                         goto f_err;
807                                 }
808                                 RSA_up_ref(rsa);
809                                 cert->rsa_tmp=rsa;
810                                 }
811                         if (rsa == NULL)
812                                 {
813                                 al=SSL_AD_HANDSHAKE_FAILURE;
814                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
815                                 goto f_err;
816                                 }
817                         r[0]=rsa->n;
818                         r[1]=rsa->e;
819                         s->s3->tmp.use_rsa_tmp=1;
820                         }
821                 else
822 #endif
823 #ifndef OPENSSL_NO_DH
824                         if (type & SSL_kEDH)
825                         {
826                         dhp=cert->dh_tmp;
827                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
828                                 dhp=s->cert->dh_tmp_cb(s,
829                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
830                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
831                         if (dhp == NULL)
832                                 {
833                                 al=SSL_AD_HANDSHAKE_FAILURE;
834                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
835                                 goto f_err;
836                                 }
837
838                         if (s->s3->tmp.dh != NULL)
839                                 {
840                                 DH_free(dh);
841                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
842                                 goto err;
843                                 }
844
845                         if ((dh=DHparams_dup(dhp)) == NULL)
846                                 {
847                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
848                                 goto err;
849                                 }
850
851                         s->s3->tmp.dh=dh;
852                         if ((dhp->pub_key == NULL ||
853                              dhp->priv_key == NULL ||
854                              (s->options & SSL_OP_SINGLE_DH_USE)))
855                                 {
856                                 if(!DH_generate_key(dh))
857                                     {
858                                     SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,
859                                            ERR_R_DH_LIB);
860                                     goto err;
861                                     }
862                                 }
863                         else
864                                 {
865                                 dh->pub_key=BN_dup(dhp->pub_key);
866                                 dh->priv_key=BN_dup(dhp->priv_key);
867                                 if ((dh->pub_key == NULL) ||
868                                         (dh->priv_key == NULL))
869                                         {
870                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
871                                         goto err;
872                                         }
873                                 }
874                         r[0]=dh->p;
875                         r[1]=dh->g;
876                         r[2]=dh->pub_key;
877                         }
878                 else 
879 #endif
880                         {
881                         al=SSL_AD_HANDSHAKE_FAILURE;
882                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
883                         goto f_err;
884                         }
885                 for (i=0; r[i] != NULL; i++)
886                         {
887                         nr[i]=BN_num_bytes(r[i]);
888                         n+=2+nr[i];
889                         }
890
891                 if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
892                         {
893                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
894                                 == NULL)
895                                 {
896                                 al=SSL_AD_DECODE_ERROR;
897                                 goto f_err;
898                                 }
899                         kn=EVP_PKEY_size(pkey);
900                         }
901                 else
902                         {
903                         pkey=NULL;
904                         kn=0;
905                         }
906
907                 if (!BUF_MEM_grow_clean(buf,n+DTLS1_HM_HEADER_LENGTH+kn))
908                         {
909                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
910                         goto err;
911                         }
912                 d=(unsigned char *)s->init_buf->data;
913                 p= &(d[DTLS1_HM_HEADER_LENGTH]);
914
915                 for (i=0; r[i] != NULL; i++)
916                         {
917                         s2n(nr[i],p);
918                         BN_bn2bin(r[i],p);
919                         p+=nr[i];
920                         }
921
922                 /* not anonymous */
923                 if (pkey != NULL)
924                         {
925                         /* n is the length of the params, they start at
926                          * &(d[DTLS1_HM_HEADER_LENGTH]) and p points to the space
927                          * at the end. */
928 #ifndef OPENSSL_NO_RSA
929                         if (pkey->type == EVP_PKEY_RSA)
930                                 {
931                                 q=md_buf;
932                                 j=0;
933                                 for (num=2; num > 0; num--)
934                                         {
935                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
936                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
937                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
938                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
939                                         EVP_DigestUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
940                                         EVP_DigestFinal_ex(&md_ctx,q,
941                                                 (unsigned int *)&i);
942                                         q+=i;
943                                         j+=i;
944                                         }
945                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
946                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
947                                         {
948                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
949                                         goto err;
950                                         }
951                                 s2n(u,p);
952                                 n+=u+2;
953                                 }
954                         else
955 #endif
956 #if !defined(OPENSSL_NO_DSA)
957                                 if (pkey->type == EVP_PKEY_DSA)
958                                 {
959                                 /* lets do DSS */
960                                 EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
961                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
962                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
963                                 EVP_SignUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
964                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
965                                         (unsigned int *)&i,pkey))
966                                         {
967                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
968                                         goto err;
969                                         }
970                                 s2n(i,p);
971                                 n+=i+2;
972                                 }
973                         else
974 #endif
975                                 {
976                                 /* Is this error check actually needed? */
977                                 al=SSL_AD_HANDSHAKE_FAILURE;
978                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
979                                 goto f_err;
980                                 }
981                         }
982
983                 d = dtls1_set_message_header(s, d,
984                         SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);
985
986                 /* we should now have things packed up, so lets send
987                  * it off */
988                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
989                 s->init_off=0;
990
991                 /* buffer the message to handle re-xmits */
992                 dtls1_buffer_message(s, 0);
993                 }
994
995         s->state = SSL3_ST_SW_KEY_EXCH_B;
996         EVP_MD_CTX_cleanup(&md_ctx);
997         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
998 f_err:
999         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1000 err:
1001         EVP_MD_CTX_cleanup(&md_ctx);
1002         return(-1);
1003         }
1004
1005 int dtls1_send_certificate_request(SSL *s)
1006         {
1007         unsigned char *p,*d;
1008         int i,j,nl,off,n;
1009         STACK_OF(X509_NAME) *sk=NULL;
1010         X509_NAME *name;
1011         BUF_MEM *buf;
1012
1013         if (s->state == SSL3_ST_SW_CERT_REQ_A)
1014                 {
1015                 buf=s->init_buf;
1016
1017                 d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
1018
1019                 /* get the list of acceptable cert types */
1020                 p++;
1021                 n=ssl3_get_req_cert_type(s,p);
1022                 d[0]=n;
1023                 p+=n;
1024                 n++;
1025
1026                 off=n;
1027                 p+=2;
1028                 n+=2;
1029
1030                 sk=SSL_get_client_CA_list(s);
1031                 nl=0;
1032                 if (sk != NULL)
1033                         {
1034                         for (i=0; i<sk_X509_NAME_num(sk); i++)
1035                                 {
1036                                 name=sk_X509_NAME_value(sk,i);
1037                                 j=i2d_X509_NAME(name,NULL);
1038                                 if (!BUF_MEM_grow_clean(buf,DTLS1_HM_HEADER_LENGTH+n+j+2))
1039                                         {
1040                                         SSLerr(SSL_F_DTLS1_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
1041                                         goto err;
1042                                         }
1043                                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+n]);
1044                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
1045                                         {
1046                                         s2n(j,p);
1047                                         i2d_X509_NAME(name,&p);
1048                                         n+=2+j;
1049                                         nl+=2+j;
1050                                         }
1051                                 else
1052                                         {
1053                                         d=p;
1054                                         i2d_X509_NAME(name,&p);
1055                                         j-=2; s2n(j,d); j+=2;
1056                                         n+=j;
1057                                         nl+=j;
1058                                         }
1059                                 }
1060                         }
1061                 /* else no CA names */
1062                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+off]);
1063                 s2n(nl,p);
1064
1065                 d=(unsigned char *)buf->data;
1066                 *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
1067                 l2n3(n,d);
1068                 s2n(s->d1->handshake_write_seq,d);
1069                 s->d1->handshake_write_seq++;
1070
1071                 /* we should now have things packed up, so lets send
1072                  * it off */
1073
1074                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1075                 s->init_off=0;
1076 #ifdef NETSCAPE_HANG_BUG
1077 /* XXX: what to do about this? */
1078                 p=(unsigned char *)s->init_buf->data + s->init_num;
1079
1080                 /* do the header */
1081                 *(p++)=SSL3_MT_SERVER_DONE;
1082                 *(p++)=0;
1083                 *(p++)=0;
1084                 *(p++)=0;
1085                 s->init_num += 4;
1086 #endif
1087
1088                 /* XDTLS:  set message header ? */
1089                 /* buffer the message to handle re-xmits */
1090                 dtls1_buffer_message(s, 0);
1091
1092                 s->state = SSL3_ST_SW_CERT_REQ_B;
1093                 }
1094
1095         /* SSL3_ST_SW_CERT_REQ_B */
1096         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1097 err:
1098         return(-1);
1099         }
1100
1101 int dtls1_send_server_certificate(SSL *s)
1102         {
1103         unsigned long l;
1104         X509 *x;
1105
1106         if (s->state == SSL3_ST_SW_CERT_A)
1107                 {
1108                 x=ssl_get_server_send_cert(s);
1109                 if (x == NULL &&
1110                         /* VRS: allow null cert if auth == KRB5 */
1111                         (s->s3->tmp.new_cipher->algorithms
1112                                 & (SSL_MKEY_MASK|SSL_AUTH_MASK))
1113                         != (SSL_aKRB5|SSL_kKRB5))
1114                         {
1115                         SSLerr(SSL_F_DTLS1_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
1116                         return(0);
1117                         }
1118
1119                 l=dtls1_output_cert_chain(s,x);
1120                 s->state=SSL3_ST_SW_CERT_B;
1121                 s->init_num=(int)l;
1122                 s->init_off=0;
1123
1124                 /* buffer the message to handle re-xmits */
1125                 dtls1_buffer_message(s, 0);
1126                 }
1127
1128         /* SSL3_ST_SW_CERT_B */
1129         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1130         }