927b01f3c477739fdab61cacea72b3f8ebb090c2
[openssl.git] / ssl / d1_srvr.c
1 /* ssl/d1_srvr.c */
2 /* 
3  * DTLS implementation written by Nagendra Modadugu
4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  
5  */
6 /* ====================================================================
7  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer. 
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    openssl-core@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
57  *
58  */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60  * All rights reserved.
61  *
62  * This package is an SSL implementation written
63  * by Eric Young (eay@cryptsoft.com).
64  * The implementation was written so as to conform with Netscapes SSL.
65  * 
66  * This library is free for commercial and non-commercial use as long as
67  * the following conditions are aheared to.  The following conditions
68  * apply to all code found in this distribution, be it the RC4, RSA,
69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
70  * included with this distribution is covered by the same copyright terms
71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72  * 
73  * Copyright remains Eric Young's, and as such any Copyright notices in
74  * the code are not to be removed.
75  * If this package is used in a product, Eric Young should be given attribution
76  * as the author of the parts of the library used.
77  * This can be in the form of a textual message at program startup or
78  * in documentation (online or textual) provided with the package.
79  * 
80  * Redistribution and use in source and binary forms, with or without
81  * modification, are permitted provided that the following conditions
82  * are met:
83  * 1. Redistributions of source code must retain the copyright
84  *    notice, this list of conditions and the following disclaimer.
85  * 2. Redistributions in binary form must reproduce the above copyright
86  *    notice, this list of conditions and the following disclaimer in the
87  *    documentation and/or other materials provided with the distribution.
88  * 3. All advertising materials mentioning features or use of this software
89  *    must display the following acknowledgement:
90  *    "This product includes cryptographic software written by
91  *     Eric Young (eay@cryptsoft.com)"
92  *    The word 'cryptographic' can be left out if the rouines from the library
93  *    being used are not cryptographic related :-).
94  * 4. If you include any Windows specific code (or a derivative thereof) from 
95  *    the apps directory (application code) you must include an acknowledgement:
96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97  * 
98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108  * SUCH DAMAGE.
109  * 
110  * The licence and distribution terms for any publically available version or
111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
112  * copied and put under another distribution licence
113  * [including the GNU Public Licence.]
114  */
115
116 #include <stdio.h>
117 #include "ssl_locl.h"
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120 #include <openssl/objects.h>
121 #include <openssl/evp.h>
122 #include <openssl/x509.h>
123 #include <openssl/md5.h>
124 #ifndef OPENSSL_NO_DH
125 #include <openssl/dh.h>
126 #endif
127
128 static SSL_METHOD *dtls1_get_server_method(int ver);
129 static int dtls1_send_hello_verify_request(SSL *s);
130
131 static SSL_METHOD *dtls1_get_server_method(int ver)
132         {
133         if (ver == DTLS1_VERSION)
134                 return(DTLSv1_server_method());
135         else
136                 return(NULL);
137         }
138
139 IMPLEMENT_dtls1_meth_func(DTLSv1_server_method,
140                         dtls1_accept,
141                         ssl_undefined_function,
142                         dtls1_get_server_method)
143
144 int dtls1_accept(SSL *s)
145         {
146         BUF_MEM *buf;
147         unsigned long l,Time=(unsigned long)time(NULL);
148         void (*cb)(const SSL *ssl,int type,int val)=NULL;
149         long num1;
150         int ret= -1;
151         int new_state,state,skip=0;
152
153         RAND_add(&Time,sizeof(Time),0);
154         ERR_clear_error();
155         clear_sys_error();
156
157         if (s->info_callback != NULL)
158                 cb=s->info_callback;
159         else if (s->ctx->info_callback != NULL)
160                 cb=s->ctx->info_callback;
161
162         /* init things to blank */
163         s->in_handshake++;
164         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
165
166         if (s->cert == NULL)
167                 {
168                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
169                 return(-1);
170                 }
171
172         for (;;)
173                 {
174                 state=s->state;
175
176                 switch (s->state)
177                         {
178                 case SSL_ST_RENEGOTIATE:
179                         s->new_session=1;
180                         /* s->state=SSL_ST_ACCEPT; */
181
182                 case SSL_ST_BEFORE:
183                 case SSL_ST_ACCEPT:
184                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
185                 case SSL_ST_OK|SSL_ST_ACCEPT:
186
187                         s->server=1;
188                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
189
190                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
191                                 {
192                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
193                                 return -1;
194                                 }
195                         s->type=SSL_ST_ACCEPT;
196
197                         if (s->init_buf == NULL)
198                                 {
199                                 if ((buf=BUF_MEM_new()) == NULL)
200                                         {
201                                         ret= -1;
202                                         goto end;
203                                         }
204                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
205                                         {
206                                         ret= -1;
207                                         goto end;
208                                         }
209                                 s->init_buf=buf;
210                                 }
211
212                         if (!ssl3_setup_buffers(s))
213                                 {
214                                 ret= -1;
215                                 goto end;
216                                 }
217
218                         s->init_num=0;
219
220                         if (s->state != SSL_ST_RENEGOTIATE)
221                                 {
222                                 /* Ok, we now need to push on a buffering BIO so that
223                                  * the output is sent in a way that TCP likes :-)
224                                  */
225                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
226
227                                 ssl3_init_finished_mac(s);
228                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
229                                 s->ctx->stats.sess_accept++;
230                                 }
231                         else
232                                 {
233                                 /* s->state == SSL_ST_RENEGOTIATE,
234                                  * we will just send a HelloRequest */
235                                 s->ctx->stats.sess_accept_renegotiate++;
236                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
237                                 }
238
239             if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
240                 s->d1->send_cookie = 1;
241             else
242                 s->d1->send_cookie = 0;
243
244                         break;
245
246                 case SSL3_ST_SW_HELLO_REQ_A:
247                 case SSL3_ST_SW_HELLO_REQ_B:
248
249                         s->shutdown=0;
250                         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
289                         /* HelloVerifyRequests resets Finished MAC */
290                         if (s->client_version != DTLS1_BAD_VER)
291                                 ssl3_init_finished_mac(s);
292                         break;
293                         
294                 case SSL3_ST_SW_SRVR_HELLO_A:
295                 case SSL3_ST_SW_SRVR_HELLO_B:
296                         ret=dtls1_send_server_hello(s);
297                         if (ret <= 0) goto end;
298
299                         if (s->hit)
300                                 s->state=SSL3_ST_SW_CHANGE_A;
301                         else
302                                 s->state=SSL3_ST_SW_CERT_A;
303                         s->init_num=0;
304                         break;
305
306                 case SSL3_ST_SW_CERT_A:
307                 case SSL3_ST_SW_CERT_B:
308                         /* Check if it is anon DH */
309                         if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
310                                 {
311                                 ret=dtls1_send_server_certificate(s);
312                                 if (ret <= 0) goto end;
313                                 }
314                         else
315                                 skip=1;
316                         s->state=SSL3_ST_SW_KEY_EXCH_A;
317                         s->init_num=0;
318                         break;
319
320                 case SSL3_ST_SW_KEY_EXCH_A:
321                 case SSL3_ST_SW_KEY_EXCH_B:
322                         l=s->s3->tmp.new_cipher->algorithms;
323
324                         /* clear this, it may get reset by
325                          * send_server_key_exchange */
326                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
327 #ifndef OPENSSL_NO_KRB5
328                                 && !(l & SSL_KRB5)
329 #endif /* OPENSSL_NO_KRB5 */
330                                 )
331                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
332                                  * even when forbidden by protocol specs
333                                  * (handshake may fail as clients are not required to
334                                  * be able to handle this) */
335                                 s->s3->tmp.use_rsa_tmp=1;
336                         else
337                                 s->s3->tmp.use_rsa_tmp=0;
338
339                         /* only send if a DH key exchange, fortezza or
340                          * RSA but we have a sign only certificate */
341                         if (s->s3->tmp.use_rsa_tmp
342                             || (l & (SSL_DH|SSL_kFZA))
343                             || ((l & SSL_kRSA)
344                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
345                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
346                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
347                                         )
348                                     )
349                                 )
350                             )
351                                 {
352                                 ret=dtls1_send_server_key_exchange(s);
353                                 if (ret <= 0) goto end;
354                                 }
355                         else
356                                 skip=1;
357
358                         s->state=SSL3_ST_SW_CERT_REQ_A;
359                         s->init_num=0;
360                         break;
361
362                 case SSL3_ST_SW_CERT_REQ_A:
363                 case SSL3_ST_SW_CERT_REQ_B:
364                         if (/* don't request cert unless asked for it: */
365                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
366                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
367                                  * don't request cert during re-negotiation: */
368                                 ((s->session->peer != NULL) &&
369                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
370                                 /* never request cert in anonymous ciphersuites
371                                  * (see section "Certificate request" in SSL 3 drafts
372                                  * and in RFC 2246): */
373                                 ((s->s3->tmp.new_cipher->algorithms & SSL_aNULL) &&
374                                  /* ... except when the application insists on verification
375                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
376                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
377                                  /* never request cert in Kerberos ciphersuites */
378                                 (s->s3->tmp.new_cipher->algorithms & SSL_aKRB5))
379                                 {
380                                 /* no cert request */
381                                 skip=1;
382                                 s->s3->tmp.cert_request=0;
383                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
384                                 }
385                         else
386                                 {
387                                 s->s3->tmp.cert_request=1;
388                                 ret=dtls1_send_certificate_request(s);
389                                 if (ret <= 0) goto end;
390 #ifndef NETSCAPE_HANG_BUG
391                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
392 #else
393                                 s->state=SSL3_ST_SW_FLUSH;
394                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
395 #endif
396                                 s->init_num=0;
397                                 }
398                         break;
399
400                 case SSL3_ST_SW_SRVR_DONE_A:
401                 case SSL3_ST_SW_SRVR_DONE_B:
402                         ret=dtls1_send_server_done(s);
403                         if (ret <= 0) goto end;
404                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
405                         s->state=SSL3_ST_SW_FLUSH;
406                         s->init_num=0;
407                         break;
408                 
409                 case SSL3_ST_SW_FLUSH:
410                         /* number of bytes to be flushed */
411                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
412                         if (num1 > 0)
413                                 {
414                                 s->rwstate=SSL_WRITING;
415                                 num1=BIO_flush(s->wbio);
416                                 if (num1 <= 0) { ret= -1; goto end; }
417                                 s->rwstate=SSL_NOTHING;
418                                 }
419
420                         s->state=s->s3->tmp.next_state;
421                         break;
422
423                 case SSL3_ST_SR_CERT_A:
424                 case SSL3_ST_SR_CERT_B:
425                         /* Check for second client hello (MS SGC) */
426                         ret = ssl3_check_client_hello(s);
427                         if (ret <= 0)
428                                 goto end;
429                         if (ret == 2)
430                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
431                         else {
432                                 /* could be sent for a DH cert, even if we
433                                  * have not asked for it :-) */
434                                 ret=ssl3_get_client_certificate(s);
435                                 if (ret <= 0) goto end;
436                                 s->init_num=0;
437                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
438                         }
439                         break;
440
441                 case SSL3_ST_SR_KEY_EXCH_A:
442                 case SSL3_ST_SR_KEY_EXCH_B:
443                         ret=ssl3_get_client_key_exchange(s);
444                         if (ret <= 0) goto end;
445                         s->state=SSL3_ST_SR_CERT_VRFY_A;
446                         s->init_num=0;
447
448                         /* We need to get hashes here so if there is
449                          * a client cert, it can be verified */ 
450                         s->method->ssl3_enc->cert_verify_mac(s,
451                                 &(s->s3->finish_dgst1),
452                                 &(s->s3->tmp.cert_verify_md[0]));
453                         s->method->ssl3_enc->cert_verify_mac(s,
454                                 &(s->s3->finish_dgst2),
455                                 &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
456
457                         break;
458
459                 case SSL3_ST_SR_CERT_VRFY_A:
460                 case SSL3_ST_SR_CERT_VRFY_B:
461
462                         /* we should decide if we expected this one */
463                         ret=ssl3_get_cert_verify(s);
464                         if (ret <= 0) goto end;
465
466                         s->state=SSL3_ST_SR_FINISHED_A;
467                         s->init_num=0;
468                         break;
469
470                 case SSL3_ST_SR_FINISHED_A:
471                 case SSL3_ST_SR_FINISHED_B:
472                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
473                                 SSL3_ST_SR_FINISHED_B);
474                         if (ret <= 0) goto end;
475                         if (s->hit)
476                                 s->state=SSL_ST_OK;
477                         else
478                                 s->state=SSL3_ST_SW_CHANGE_A;
479                         s->init_num=0;
480                         break;
481
482                 case SSL3_ST_SW_CHANGE_A:
483                 case SSL3_ST_SW_CHANGE_B:
484
485                         s->session->cipher=s->s3->tmp.new_cipher;
486                         if (!s->method->ssl3_enc->setup_key_block(s))
487                                 { ret= -1; goto end; }
488
489                         ret=dtls1_send_change_cipher_spec(s,
490                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
491
492                         if (ret <= 0) goto end;
493                         s->state=SSL3_ST_SW_FINISHED_A;
494                         s->init_num=0;
495
496                         if (!s->method->ssl3_enc->change_cipher_state(s,
497                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
498                                 {
499                                 ret= -1;
500                                 goto end;
501                                 }
502
503                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
504                         break;
505
506                 case SSL3_ST_SW_FINISHED_A:
507                 case SSL3_ST_SW_FINISHED_B:
508                         ret=dtls1_send_finished(s,
509                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
510                                 s->method->ssl3_enc->server_finished_label,
511                                 s->method->ssl3_enc->server_finished_label_len);
512                         if (ret <= 0) goto end;
513                         s->state=SSL3_ST_SW_FLUSH;
514                         if (s->hit)
515                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
516                         else
517                                 s->s3->tmp.next_state=SSL_ST_OK;
518                         s->init_num=0;
519                         break;
520
521                 case SSL_ST_OK:
522                         /* clean a few things up */
523                         ssl3_cleanup_key_block(s);
524
525 #if 0
526                         BUF_MEM_free(s->init_buf);
527                         s->init_buf=NULL;
528 #endif
529
530                         /* remove buffering on output */
531                         ssl_free_wbio_buffer(s);
532
533                         s->init_num=0;
534
535                         if (s->new_session == 2) /* skipped if we just sent a HelloRequest */
536                                 {
537                                 /* actually not necessarily a 'new' session unless
538                                  * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
539                                 
540                                 s->new_session=0;
541                                 
542                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
543                                 
544                                 s->ctx->stats.sess_accept_good++;
545                                 /* s->server=1; */
546                                 s->handshake_func=dtls1_accept;
547
548                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
549                                 }
550                         
551                         ret = 1;
552
553                         /* done handshaking, next message is client hello */
554                         s->d1->handshake_read_seq = 0;
555                         /* next message is server hello */
556                         s->d1->handshake_write_seq = 0;
557                         goto end;
558                         /* break; */
559
560                 default:
561                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
562                         ret= -1;
563                         goto end;
564                         /* break; */
565                         }
566                 
567                 if (!s->s3->tmp.reuse_message && !skip)
568                         {
569                         if (s->debug)
570                                 {
571                                 if ((ret=BIO_flush(s->wbio)) <= 0)
572                                         goto end;
573                                 }
574
575
576                         if ((cb != NULL) && (s->state != state))
577                                 {
578                                 new_state=s->state;
579                                 s->state=state;
580                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
581                                 s->state=new_state;
582                                 }
583                         }
584                 skip=0;
585                 }
586 end:
587         /* BIO_flush(s->wbio); */
588
589         s->in_handshake--;
590         if (cb != NULL)
591                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
592         return(ret);
593         }
594
595 int dtls1_send_hello_request(SSL *s)
596         {
597         unsigned char *p;
598
599         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
600                 {
601                 p=(unsigned char *)s->init_buf->data;
602                 p = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);
603
604                 s->state=SSL3_ST_SW_HELLO_REQ_B;
605                 /* number of bytes to write */
606                 s->init_num=DTLS1_HM_HEADER_LENGTH;
607                 s->init_off=0;
608
609                 /* no need to buffer this message, since there are no retransmit 
610                  * requests for it */
611                 }
612
613         /* SSL3_ST_SW_HELLO_REQ_B */
614         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
615         }
616
617 int dtls1_send_hello_verify_request(SSL *s)
618         {
619         unsigned int msg_len;
620         unsigned char *msg, *buf, *p;
621
622         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
623                 {
624                 buf = (unsigned char *)s->init_buf->data;
625
626                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
627                 if (s->client_version == DTLS1_BAD_VER)
628                         *(p++) = DTLS1_BAD_VER>>8,
629                         *(p++) = DTLS1_BAD_VER&0xff;
630                 else
631                         *(p++) = s->version >> 8,
632                         *(p++) = s->version & 0xFF;
633
634                 if (s->ctx->app_gen_cookie_cb != NULL &&
635                     s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 
636                     &(s->d1->cookie_len)) == 0)
637                         {
638                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
639                         return 0;
640                         }
641                 /* else the cookie is assumed to have 
642                  * been initialized by the application */
643
644                 *(p++) = (unsigned char) s->d1->cookie_len;
645                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
646                 p += s->d1->cookie_len;
647                 msg_len = p - msg;
648
649                 dtls1_set_message_header(s, buf,
650                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
651
652                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
653                 /* number of bytes to write */
654                 s->init_num=p-buf;
655                 s->init_off=0;
656
657                 /* buffer the message to handle re-xmits */
658                 dtls1_buffer_message(s, 0);
659                 }
660
661         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
662         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
663         }
664
665 int dtls1_send_server_hello(SSL *s)
666         {
667         unsigned char *buf;
668         unsigned char *p,*d;
669         int i;
670         unsigned int sl;
671         unsigned long l,Time;
672
673         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
674                 {
675                 buf=(unsigned char *)s->init_buf->data;
676                 p=s->s3->server_random;
677                 Time=(unsigned long)time(NULL);                 /* Time */
678                 l2n(Time,p);
679                 RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));
680                 /* Do the message type and length last */
681                 d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);
682
683                 if (s->client_version == DTLS1_BAD_VER)
684                         *(p++)=DTLS1_BAD_VER>>8,
685                         *(p++)=DTLS1_BAD_VER&0xff;
686                 else
687                         *(p++)=s->version>>8,
688                         *(p++)=s->version&0xff;
689
690                 /* Random stuff */
691                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
692                 p+=SSL3_RANDOM_SIZE;
693
694                 /* now in theory we have 3 options to sending back the
695                  * session id.  If it is a re-use, we send back the
696                  * old session-id, if it is a new session, we send
697                  * back the new session-id or we send back a 0 length
698                  * session-id if we want it to be single use.
699                  * Currently I will not implement the '0' length session-id
700                  * 12-Jan-98 - I'll now support the '0' length stuff.
701                  */
702                 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
703                         s->session->session_id_length=0;
704
705                 sl=s->session->session_id_length;
706                 if (sl > sizeof s->session->session_id)
707                         {
708                         SSLerr(SSL_F_DTLS1_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
709                         return -1;
710                         }
711                 *(p++)=sl;
712                 memcpy(p,s->session->session_id,sl);
713                 p+=sl;
714
715                 /* put the cipher */
716                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
717                 p+=i;
718
719                 /* put the compression method */
720 #ifdef OPENSSL_NO_COMP
721                 *(p++)=0;
722 #else
723                 if (s->s3->tmp.new_compression == NULL)
724                         *(p++)=0;
725                 else
726                         *(p++)=s->s3->tmp.new_compression->id;
727 #endif
728
729                 /* do the header */
730                 l=(p-d);
731                 d=buf;
732
733                 d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);
734
735                 s->state=SSL3_ST_CW_CLNT_HELLO_B;
736                 /* number of bytes to write */
737                 s->init_num=p-buf;
738                 s->init_off=0;
739
740                 /* buffer the message to handle re-xmits */
741                 dtls1_buffer_message(s, 0);
742                 }
743
744         /* SSL3_ST_CW_CLNT_HELLO_B */
745         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
746         }
747
748 int dtls1_send_server_done(SSL *s)
749         {
750         unsigned char *p;
751
752         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
753                 {
754                 p=(unsigned char *)s->init_buf->data;
755
756                 /* do the header */
757                 p = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);
758
759                 s->state=SSL3_ST_SW_SRVR_DONE_B;
760                 /* number of bytes to write */
761                 s->init_num=DTLS1_HM_HEADER_LENGTH;
762                 s->init_off=0;
763
764                 /* buffer the message to handle re-xmits */
765                 dtls1_buffer_message(s, 0);
766                 }
767
768         /* SSL3_ST_CW_CLNT_HELLO_B */
769         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
770         }
771
772 int dtls1_send_server_key_exchange(SSL *s)
773         {
774 #ifndef OPENSSL_NO_RSA
775         unsigned char *q;
776         int j,num;
777         RSA *rsa;
778         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
779         unsigned int u;
780 #endif
781 #ifndef OPENSSL_NO_DH
782         DH *dh=NULL,*dhp;
783 #endif
784         EVP_PKEY *pkey;
785         unsigned char *p,*d;
786         int al,i;
787         unsigned long type;
788         int n;
789         CERT *cert;
790         BIGNUM *r[4];
791         int nr[4],kn;
792         BUF_MEM *buf;
793         EVP_MD_CTX md_ctx;
794
795         EVP_MD_CTX_init(&md_ctx);
796         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
797                 {
798                 type=s->s3->tmp.new_cipher->algorithms & SSL_MKEY_MASK;
799                 cert=s->cert;
800
801                 buf=s->init_buf;
802
803                 r[0]=r[1]=r[2]=r[3]=NULL;
804                 n=0;
805 #ifndef OPENSSL_NO_RSA
806                 if (type & SSL_kRSA)
807                         {
808                         rsa=cert->rsa_tmp;
809                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
810                                 {
811                                 rsa=s->cert->rsa_tmp_cb(s,
812                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
813                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
814                                 if(rsa == NULL)
815                                 {
816                                         al=SSL_AD_HANDSHAKE_FAILURE;
817                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
818                                         goto f_err;
819                                 }
820                                 RSA_up_ref(rsa);
821                                 cert->rsa_tmp=rsa;
822                                 }
823                         if (rsa == NULL)
824                                 {
825                                 al=SSL_AD_HANDSHAKE_FAILURE;
826                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
827                                 goto f_err;
828                                 }
829                         r[0]=rsa->n;
830                         r[1]=rsa->e;
831                         s->s3->tmp.use_rsa_tmp=1;
832                         }
833                 else
834 #endif
835 #ifndef OPENSSL_NO_DH
836                         if (type & SSL_kEDH)
837                         {
838                         dhp=cert->dh_tmp;
839                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
840                                 dhp=s->cert->dh_tmp_cb(s,
841                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
842                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
843                         if (dhp == NULL)
844                                 {
845                                 al=SSL_AD_HANDSHAKE_FAILURE;
846                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
847                                 goto f_err;
848                                 }
849
850                         if (s->s3->tmp.dh != NULL)
851                                 {
852                                 DH_free(dh);
853                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
854                                 goto err;
855                                 }
856
857                         if ((dh=DHparams_dup(dhp)) == NULL)
858                                 {
859                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
860                                 goto err;
861                                 }
862
863                         s->s3->tmp.dh=dh;
864                         if ((dhp->pub_key == NULL ||
865                              dhp->priv_key == NULL ||
866                              (s->options & SSL_OP_SINGLE_DH_USE)))
867                                 {
868                                 if(!DH_generate_key(dh))
869                                     {
870                                     SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,
871                                            ERR_R_DH_LIB);
872                                     goto err;
873                                     }
874                                 }
875                         else
876                                 {
877                                 dh->pub_key=BN_dup(dhp->pub_key);
878                                 dh->priv_key=BN_dup(dhp->priv_key);
879                                 if ((dh->pub_key == NULL) ||
880                                         (dh->priv_key == NULL))
881                                         {
882                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
883                                         goto err;
884                                         }
885                                 }
886                         r[0]=dh->p;
887                         r[1]=dh->g;
888                         r[2]=dh->pub_key;
889                         }
890                 else 
891 #endif
892                         {
893                         al=SSL_AD_HANDSHAKE_FAILURE;
894                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
895                         goto f_err;
896                         }
897                 for (i=0; r[i] != NULL; i++)
898                         {
899                         nr[i]=BN_num_bytes(r[i]);
900                         n+=2+nr[i];
901                         }
902
903                 if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
904                         {
905                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
906                                 == NULL)
907                                 {
908                                 al=SSL_AD_DECODE_ERROR;
909                                 goto f_err;
910                                 }
911                         kn=EVP_PKEY_size(pkey);
912                         }
913                 else
914                         {
915                         pkey=NULL;
916                         kn=0;
917                         }
918
919                 if (!BUF_MEM_grow_clean(buf,n+DTLS1_HM_HEADER_LENGTH+kn))
920                         {
921                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
922                         goto err;
923                         }
924                 d=(unsigned char *)s->init_buf->data;
925                 p= &(d[DTLS1_HM_HEADER_LENGTH]);
926
927                 for (i=0; r[i] != NULL; i++)
928                         {
929                         s2n(nr[i],p);
930                         BN_bn2bin(r[i],p);
931                         p+=nr[i];
932                         }
933
934                 /* not anonymous */
935                 if (pkey != NULL)
936                         {
937                         /* n is the length of the params, they start at
938                          * &(d[DTLS1_HM_HEADER_LENGTH]) and p points to the space
939                          * at the end. */
940 #ifndef OPENSSL_NO_RSA
941                         if (pkey->type == EVP_PKEY_RSA)
942                                 {
943                                 q=md_buf;
944                                 j=0;
945                                 for (num=2; num > 0; num--)
946                                         {
947                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
948                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
949                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
950                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
951                                         EVP_DigestUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
952                                         EVP_DigestFinal_ex(&md_ctx,q,
953                                                 (unsigned int *)&i);
954                                         q+=i;
955                                         j+=i;
956                                         }
957                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
958                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
959                                         {
960                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
961                                         goto err;
962                                         }
963                                 s2n(u,p);
964                                 n+=u+2;
965                                 }
966                         else
967 #endif
968 #if !defined(OPENSSL_NO_DSA)
969                                 if (pkey->type == EVP_PKEY_DSA)
970                                 {
971                                 /* lets do DSS */
972                                 EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
973                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
974                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
975                                 EVP_SignUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
976                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
977                                         (unsigned int *)&i,pkey))
978                                         {
979                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
980                                         goto err;
981                                         }
982                                 s2n(i,p);
983                                 n+=i+2;
984                                 }
985                         else
986 #endif
987                                 {
988                                 /* Is this error check actually needed? */
989                                 al=SSL_AD_HANDSHAKE_FAILURE;
990                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
991                                 goto f_err;
992                                 }
993                         }
994
995                 d = dtls1_set_message_header(s, d,
996                         SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);
997
998                 /* we should now have things packed up, so lets send
999                  * it off */
1000                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1001                 s->init_off=0;
1002
1003                 /* buffer the message to handle re-xmits */
1004                 dtls1_buffer_message(s, 0);
1005                 }
1006
1007         s->state = SSL3_ST_SW_KEY_EXCH_B;
1008         EVP_MD_CTX_cleanup(&md_ctx);
1009         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1010 f_err:
1011         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1012 err:
1013         EVP_MD_CTX_cleanup(&md_ctx);
1014         return(-1);
1015         }
1016
1017 int dtls1_send_certificate_request(SSL *s)
1018         {
1019         unsigned char *p,*d;
1020         int i,j,nl,off,n;
1021         STACK_OF(X509_NAME) *sk=NULL;
1022         X509_NAME *name;
1023         BUF_MEM *buf;
1024         unsigned int msg_len;
1025
1026         if (s->state == SSL3_ST_SW_CERT_REQ_A)
1027                 {
1028                 buf=s->init_buf;
1029
1030                 d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
1031
1032                 /* get the list of acceptable cert types */
1033                 p++;
1034                 n=ssl3_get_req_cert_type(s,p);
1035                 d[0]=n;
1036                 p+=n;
1037                 n++;
1038
1039                 off=n;
1040                 p+=2;
1041                 n+=2;
1042
1043                 sk=SSL_get_client_CA_list(s);
1044                 nl=0;
1045                 if (sk != NULL)
1046                         {
1047                         for (i=0; i<sk_X509_NAME_num(sk); i++)
1048                                 {
1049                                 name=sk_X509_NAME_value(sk,i);
1050                                 j=i2d_X509_NAME(name,NULL);
1051                                 if (!BUF_MEM_grow_clean(buf,DTLS1_HM_HEADER_LENGTH+n+j+2))
1052                                         {
1053                                         SSLerr(SSL_F_DTLS1_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
1054                                         goto err;
1055                                         }
1056                                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+n]);
1057                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
1058                                         {
1059                                         s2n(j,p);
1060                                         i2d_X509_NAME(name,&p);
1061                                         n+=2+j;
1062                                         nl+=2+j;
1063                                         }
1064                                 else
1065                                         {
1066                                         d=p;
1067                                         i2d_X509_NAME(name,&p);
1068                                         j-=2; s2n(j,d); j+=2;
1069                                         n+=j;
1070                                         nl+=j;
1071                                         }
1072                                 }
1073                         }
1074                 /* else no CA names */
1075                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+off]);
1076                 s2n(nl,p);
1077
1078                 d=(unsigned char *)buf->data;
1079                 *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
1080                 l2n3(n,d);
1081                 s2n(s->d1->handshake_write_seq,d);
1082                 s->d1->handshake_write_seq++;
1083
1084                 /* we should now have things packed up, so lets send
1085                  * it off */
1086
1087                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1088                 s->init_off=0;
1089 #ifdef NETSCAPE_HANG_BUG
1090 /* XXX: what to do about this? */
1091                 p=(unsigned char *)s->init_buf->data + s->init_num;
1092
1093                 /* do the header */
1094                 *(p++)=SSL3_MT_SERVER_DONE;
1095                 *(p++)=0;
1096                 *(p++)=0;
1097                 *(p++)=0;
1098                 s->init_num += 4;
1099 #endif
1100
1101                 /* XDTLS:  set message header ? */
1102                 msg_len = s->init_num - DTLS1_HM_HEADER_LENGTH;
1103                 dtls1_set_message_header(s, (void *)s->init_buf->data,
1104                         SSL3_MT_CERTIFICATE_REQUEST, msg_len, 0, msg_len);
1105
1106                 /* buffer the message to handle re-xmits */
1107                 dtls1_buffer_message(s, 0);
1108
1109                 s->state = SSL3_ST_SW_CERT_REQ_B;
1110                 }
1111
1112         /* SSL3_ST_SW_CERT_REQ_B */
1113         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1114 err:
1115         return(-1);
1116         }
1117
1118 int dtls1_send_server_certificate(SSL *s)
1119         {
1120         unsigned long l;
1121         X509 *x;
1122
1123         if (s->state == SSL3_ST_SW_CERT_A)
1124                 {
1125                 x=ssl_get_server_send_cert(s);
1126                 if (x == NULL &&
1127                         /* VRS: allow null cert if auth == KRB5 */
1128                         (s->s3->tmp.new_cipher->algorithms
1129                                 & (SSL_MKEY_MASK|SSL_AUTH_MASK))
1130                         != (SSL_aKRB5|SSL_kKRB5))
1131                         {
1132                         SSLerr(SSL_F_DTLS1_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
1133                         return(0);
1134                         }
1135
1136                 l=dtls1_output_cert_chain(s,x);
1137                 s->state=SSL3_ST_SW_CERT_B;
1138                 s->init_num=(int)l;
1139                 s->init_off=0;
1140
1141                 /* buffer the message to handle re-xmits */
1142                 dtls1_buffer_message(s, 0);
1143                 }
1144
1145         /* SSL3_ST_SW_CERT_B */
1146         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1147         }