fix warning
[openssl.git] / ssl / d1_srvr.c
1 /* ssl/d1_srvr.c */
2 /* 
3  * DTLS implementation written by Nagendra Modadugu
4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  
5  */
6 /* ====================================================================
7  * Copyright (c) 1999-2007 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer. 
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    openssl-core@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
57  *
58  */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60  * All rights reserved.
61  *
62  * This package is an SSL implementation written
63  * by Eric Young (eay@cryptsoft.com).
64  * The implementation was written so as to conform with Netscapes SSL.
65  * 
66  * This library is free for commercial and non-commercial use as long as
67  * the following conditions are aheared to.  The following conditions
68  * apply to all code found in this distribution, be it the RC4, RSA,
69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
70  * included with this distribution is covered by the same copyright terms
71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72  * 
73  * Copyright remains Eric Young's, and as such any Copyright notices in
74  * the code are not to be removed.
75  * If this package is used in a product, Eric Young should be given attribution
76  * as the author of the parts of the library used.
77  * This can be in the form of a textual message at program startup or
78  * in documentation (online or textual) provided with the package.
79  * 
80  * Redistribution and use in source and binary forms, with or without
81  * modification, are permitted provided that the following conditions
82  * are met:
83  * 1. Redistributions of source code must retain the copyright
84  *    notice, this list of conditions and the following disclaimer.
85  * 2. Redistributions in binary form must reproduce the above copyright
86  *    notice, this list of conditions and the following disclaimer in the
87  *    documentation and/or other materials provided with the distribution.
88  * 3. All advertising materials mentioning features or use of this software
89  *    must display the following acknowledgement:
90  *    "This product includes cryptographic software written by
91  *     Eric Young (eay@cryptsoft.com)"
92  *    The word 'cryptographic' can be left out if the rouines from the library
93  *    being used are not cryptographic related :-).
94  * 4. If you include any Windows specific code (or a derivative thereof) from 
95  *    the apps directory (application code) you must include an acknowledgement:
96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97  * 
98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108  * SUCH DAMAGE.
109  * 
110  * The licence and distribution terms for any publically available version or
111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
112  * copied and put under another distribution licence
113  * [including the GNU Public Licence.]
114  */
115
116 #include <stdio.h>
117 #include "ssl_locl.h"
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120 #include <openssl/objects.h>
121 #include <openssl/evp.h>
122 #include <openssl/x509.h>
123 #include <openssl/md5.h>
124 #include <openssl/bn.h>
125 #ifndef OPENSSL_NO_DH
126 #include <openssl/dh.h>
127 #endif
128
129 static const SSL_METHOD *dtls1_get_server_method(int ver);
130 static int dtls1_send_hello_verify_request(SSL *s);
131
132 static const SSL_METHOD *dtls1_get_server_method(int ver)
133         {
134         if (ver == DTLS1_VERSION)
135                 return(DTLSv1_server_method());
136         else
137                 return(NULL);
138         }
139
140 IMPLEMENT_dtls1_meth_func(DTLSv1_server_method,
141                         dtls1_accept,
142                         ssl_undefined_function,
143                         dtls1_get_server_method)
144
145 int dtls1_accept(SSL *s)
146         {
147         BUF_MEM *buf;
148         unsigned long Time=(unsigned long)time(NULL);
149         void (*cb)(const SSL *ssl,int type,int val)=NULL;
150         long num1;
151         unsigned long alg_k;
152         int ret= -1;
153         int new_state,state,skip=0;
154
155         RAND_add(&Time,sizeof(Time),0);
156         ERR_clear_error();
157         clear_sys_error();
158
159         if (s->info_callback != NULL)
160                 cb=s->info_callback;
161         else if (s->ctx->info_callback != NULL)
162                 cb=s->ctx->info_callback;
163
164         /* init things to blank */
165         s->in_handshake++;
166         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
167
168         if (s->cert == NULL)
169                 {
170                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
171                 return(-1);
172                 }
173
174         for (;;)
175                 {
176                 state=s->state;
177
178                 switch (s->state)
179                         {
180                 case SSL_ST_RENEGOTIATE:
181                         s->new_session=1;
182                         /* s->state=SSL_ST_ACCEPT; */
183
184                 case SSL_ST_BEFORE:
185                 case SSL_ST_ACCEPT:
186                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
187                 case SSL_ST_OK|SSL_ST_ACCEPT:
188
189                         s->server=1;
190                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
191
192                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
193                                 {
194                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
195                                 return -1;
196                                 }
197                         s->type=SSL_ST_ACCEPT;
198
199                         if (s->init_buf == NULL)
200                                 {
201                                 if ((buf=BUF_MEM_new()) == NULL)
202                                         {
203                                         ret= -1;
204                                         goto end;
205                                         }
206                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
207                                         {
208                                         ret= -1;
209                                         goto end;
210                                         }
211                                 s->init_buf=buf;
212                                 }
213
214                         if (!ssl3_setup_buffers(s))
215                                 {
216                                 ret= -1;
217                                 goto end;
218                                 }
219
220                         s->init_num=0;
221
222                         if (s->state != SSL_ST_RENEGOTIATE)
223                                 {
224                                 /* Ok, we now need to push on a buffering BIO so that
225                                  * the output is sent in a way that TCP likes :-)
226                                  */
227                                 if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
228
229                                 ssl3_init_finished_mac(s);
230                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
231                                 s->ctx->stats.sess_accept++;
232                                 }
233                         else
234                                 {
235                                 /* s->state == SSL_ST_RENEGOTIATE,
236                                  * we will just send a HelloRequest */
237                                 s->ctx->stats.sess_accept_renegotiate++;
238                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
239                                 }
240
241                         if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
242                                 s->d1->send_cookie = 1;
243                         else
244                                 s->d1->send_cookie = 0;
245                         
246                         break;
247
248                 case SSL3_ST_SW_HELLO_REQ_A:
249                 case SSL3_ST_SW_HELLO_REQ_B:
250
251                         s->shutdown=0;
252                         ret=dtls1_send_hello_request(s);
253                         if (ret <= 0) goto end;
254                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
255                         s->state=SSL3_ST_SW_FLUSH;
256                         s->init_num=0;
257
258                         ssl3_init_finished_mac(s);
259                         break;
260
261                 case SSL3_ST_SW_HELLO_REQ_C:
262                         s->state=SSL_ST_OK;
263                         break;
264
265                 case SSL3_ST_SR_CLNT_HELLO_A:
266                 case SSL3_ST_SR_CLNT_HELLO_B:
267                 case SSL3_ST_SR_CLNT_HELLO_C:
268
269                         s->shutdown=0;
270                         ret=ssl3_get_client_hello(s);
271                         if (ret <= 0) goto end;
272                         s->new_session = 2;
273
274                         if (s->d1->send_cookie)
275                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
276                         else
277                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
278
279                         s->init_num=0;
280                         break;
281                         
282                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
283                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
284
285                         ret = dtls1_send_hello_verify_request(s);
286                         if ( ret <= 0) goto end;
287                         s->d1->send_cookie = 0;
288                         s->state=SSL3_ST_SW_FLUSH;
289                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
290                         break;
291                         
292                 case SSL3_ST_SW_SRVR_HELLO_A:
293                 case SSL3_ST_SW_SRVR_HELLO_B:
294                         ret=dtls1_send_server_hello(s);
295                         if (ret <= 0) goto end;
296
297                         if (s->hit)
298                                 s->state=SSL3_ST_SW_CHANGE_A;
299                         else
300                                 s->state=SSL3_ST_SW_CERT_A;
301                         s->init_num=0;
302                         break;
303
304                 case SSL3_ST_SW_CERT_A:
305                 case SSL3_ST_SW_CERT_B:
306                         /* Check if it is anon DH */
307                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL))
308                                 {
309                                 ret=dtls1_send_server_certificate(s);
310                                 if (ret <= 0) goto end;
311                                 }
312                         else
313                                 skip=1;
314                         s->state=SSL3_ST_SW_KEY_EXCH_A;
315                         s->init_num=0;
316                         break;
317
318                 case SSL3_ST_SW_KEY_EXCH_A:
319                 case SSL3_ST_SW_KEY_EXCH_B:
320                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
321
322                         /* clear this, it may get reset by
323                          * send_server_key_exchange */
324                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
325 #ifndef OPENSSL_NO_KRB5
326                                 && !(alg_k & SSL_kKRB5)
327 #endif /* OPENSSL_NO_KRB5 */
328                                 )
329                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
330                                  * even when forbidden by protocol specs
331                                  * (handshake may fail as clients are not required to
332                                  * be able to handle this) */
333                                 s->s3->tmp.use_rsa_tmp=1;
334                         else
335                                 s->s3->tmp.use_rsa_tmp=0;
336
337                         /* only send if a DH key exchange or
338                          * RSA but we have a sign only certificate */
339                         if (s->s3->tmp.use_rsa_tmp
340                             || (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
341                             || ((alg_k & SSL_kRSA)
342                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
343                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
344                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
345                                         )
346                                     )
347                                 )
348                             )
349                                 {
350                                 ret=dtls1_send_server_key_exchange(s);
351                                 if (ret <= 0) goto end;
352                                 }
353                         else
354                                 skip=1;
355
356                         s->state=SSL3_ST_SW_CERT_REQ_A;
357                         s->init_num=0;
358                         break;
359
360                 case SSL3_ST_SW_CERT_REQ_A:
361                 case SSL3_ST_SW_CERT_REQ_B:
362                         if (/* don't request cert unless asked for it: */
363                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
364                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
365                                  * don't request cert during re-negotiation: */
366                                 ((s->session->peer != NULL) &&
367                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
368                                 /* never request cert in anonymous ciphersuites
369                                  * (see section "Certificate request" in SSL 3 drafts
370                                  * and in RFC 2246): */
371                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
372                                  /* ... except when the application insists on verification
373                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
374                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
375                                  /* never request cert in Kerberos ciphersuites */
376                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5))
377                                 {
378                                 /* no cert request */
379                                 skip=1;
380                                 s->s3->tmp.cert_request=0;
381                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
382                                 }
383                         else
384                                 {
385                                 s->s3->tmp.cert_request=1;
386                                 ret=dtls1_send_certificate_request(s);
387                                 if (ret <= 0) goto end;
388 #ifndef NETSCAPE_HANG_BUG
389                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
390 #else
391                                 s->state=SSL3_ST_SW_FLUSH;
392                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
393 #endif
394                                 s->init_num=0;
395                                 }
396                         break;
397
398                 case SSL3_ST_SW_SRVR_DONE_A:
399                 case SSL3_ST_SW_SRVR_DONE_B:
400                         ret=dtls1_send_server_done(s);
401                         if (ret <= 0) goto end;
402                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
403                         s->state=SSL3_ST_SW_FLUSH;
404                         s->init_num=0;
405                         break;
406                 
407                 case SSL3_ST_SW_FLUSH:
408                         /* number of bytes to be flushed */
409                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
410                         if (num1 > 0)
411                                 {
412                                 s->rwstate=SSL_WRITING;
413                                 num1=BIO_flush(s->wbio);
414                                 if (num1 <= 0) { ret= -1; goto end; }
415                                 s->rwstate=SSL_NOTHING;
416                                 }
417
418                         s->state=s->s3->tmp.next_state;
419                         break;
420
421                 case SSL3_ST_SR_CERT_A:
422                 case SSL3_ST_SR_CERT_B:
423                         /* Check for second client hello (MS SGC) */
424                         ret = ssl3_check_client_hello(s);
425                         if (ret <= 0)
426                                 goto end;
427                         if (ret == 2)
428                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
429                         else {
430                                 /* could be sent for a DH cert, even if we
431                                  * have not asked for it :-) */
432                                 ret=ssl3_get_client_certificate(s);
433                                 if (ret <= 0) goto end;
434                                 s->init_num=0;
435                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
436                         }
437                         break;
438
439                 case SSL3_ST_SR_KEY_EXCH_A:
440                 case SSL3_ST_SR_KEY_EXCH_B:
441                         ret=ssl3_get_client_key_exchange(s);
442                         if (ret <= 0) goto end;
443                         s->state=SSL3_ST_SR_CERT_VRFY_A;
444                         s->init_num=0;
445
446                         /* We need to get hashes here so if there is
447                          * a client cert, it can be verified */ 
448                         s->method->ssl3_enc->cert_verify_mac(s,
449                                 NID_md5,
450                                 &(s->s3->tmp.cert_verify_md[0]));
451                         s->method->ssl3_enc->cert_verify_mac(s,
452                                 NID_sha1,
453                                 &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
454
455                         break;
456
457                 case SSL3_ST_SR_CERT_VRFY_A:
458                 case SSL3_ST_SR_CERT_VRFY_B:
459
460                         /* we should decide if we expected this one */
461                         ret=ssl3_get_cert_verify(s);
462                         if (ret <= 0) goto end;
463
464                         s->state=SSL3_ST_SR_FINISHED_A;
465                         s->init_num=0;
466                         break;
467
468                 case SSL3_ST_SR_FINISHED_A:
469                 case SSL3_ST_SR_FINISHED_B:
470                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
471                                 SSL3_ST_SR_FINISHED_B);
472                         if (ret <= 0) goto end;
473                         if (s->hit)
474                                 s->state=SSL_ST_OK;
475                         else
476                                 s->state=SSL3_ST_SW_CHANGE_A;
477                         s->init_num=0;
478                         break;
479
480                 case SSL3_ST_SW_CHANGE_A:
481                 case SSL3_ST_SW_CHANGE_B:
482
483                         s->session->cipher=s->s3->tmp.new_cipher;
484                         if (!s->method->ssl3_enc->setup_key_block(s))
485                                 { ret= -1; goto end; }
486
487                         ret=dtls1_send_change_cipher_spec(s,
488                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
489
490                         if (ret <= 0) goto end;
491                         s->state=SSL3_ST_SW_FINISHED_A;
492                         s->init_num=0;
493
494                         if (!s->method->ssl3_enc->change_cipher_state(s,
495                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
496                                 {
497                                 ret= -1;
498                                 goto end;
499                                 }
500
501                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
502                         break;
503
504                 case SSL3_ST_SW_FINISHED_A:
505                 case SSL3_ST_SW_FINISHED_B:
506                         ret=dtls1_send_finished(s,
507                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
508                                 s->method->ssl3_enc->server_finished_label,
509                                 s->method->ssl3_enc->server_finished_label_len);
510                         if (ret <= 0) goto end;
511                         s->state=SSL3_ST_SW_FLUSH;
512                         if (s->hit)
513                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
514                         else
515                                 s->s3->tmp.next_state=SSL_ST_OK;
516                         s->init_num=0;
517                         break;
518
519                 case SSL_ST_OK:
520                         /* clean a few things up */
521                         ssl3_cleanup_key_block(s);
522
523 #if 0
524                         BUF_MEM_free(s->init_buf);
525                         s->init_buf=NULL;
526 #endif
527
528                         /* remove buffering on output */
529                         ssl_free_wbio_buffer(s);
530
531                         s->init_num=0;
532
533                         if (s->new_session == 2) /* skipped if we just sent a HelloRequest */
534                                 {
535                                 /* actually not necessarily a 'new' session unless
536                                  * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION is set */
537                                 
538                                 s->new_session=0;
539                                 
540                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
541                                 
542                                 s->ctx->stats.sess_accept_good++;
543                                 /* s->server=1; */
544                                 s->handshake_func=dtls1_accept;
545
546                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
547                                 }
548                         
549                         ret = 1;
550
551                         /* done handshaking, next message is client hello */
552                         s->d1->handshake_read_seq = 0;
553                         /* next message is server hello */
554                         s->d1->handshake_write_seq = 0;
555                         goto end;
556                         /* break; */
557
558                 default:
559                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
560                         ret= -1;
561                         goto end;
562                         /* break; */
563                         }
564                 
565                 if (!s->s3->tmp.reuse_message && !skip)
566                         {
567                         if (s->debug)
568                                 {
569                                 if ((ret=BIO_flush(s->wbio)) <= 0)
570                                         goto end;
571                                 }
572
573
574                         if ((cb != NULL) && (s->state != state))
575                                 {
576                                 new_state=s->state;
577                                 s->state=state;
578                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
579                                 s->state=new_state;
580                                 }
581                         }
582                 skip=0;
583                 }
584 end:
585         /* BIO_flush(s->wbio); */
586
587         s->in_handshake--;
588         if (cb != NULL)
589                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
590         return(ret);
591         }
592
593 int dtls1_send_hello_request(SSL *s)
594         {
595         unsigned char *p;
596
597         if (s->state == SSL3_ST_SW_HELLO_REQ_A)
598                 {
599                 p=(unsigned char *)s->init_buf->data;
600                 p = dtls1_set_message_header(s, p, SSL3_MT_HELLO_REQUEST, 0, 0, 0);
601
602                 s->state=SSL3_ST_SW_HELLO_REQ_B;
603                 /* number of bytes to write */
604                 s->init_num=DTLS1_HM_HEADER_LENGTH;
605                 s->init_off=0;
606
607                 /* no need to buffer this message, since there are no retransmit 
608                  * requests for it */
609                 }
610
611         /* SSL3_ST_SW_HELLO_REQ_B */
612         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
613         }
614
615 int dtls1_send_hello_verify_request(SSL *s)
616         {
617         unsigned int msg_len;
618         unsigned char *msg, *buf, *p;
619
620         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
621                 {
622                 buf = (unsigned char *)s->init_buf->data;
623
624                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
625                 *(p++) = s->version >> 8;
626                 *(p++) = s->version & 0xFF;
627
628                 *(p++) = (unsigned char) s->d1->cookie_len;
629         if (s->ctx->app_gen_cookie_cb != NULL &&
630             s->ctx->app_gen_cookie_cb(s, s->d1->cookie, 
631                 &(s->d1->cookie_len)) == 0)
632                 {
633                 SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
634                 return 0;
635                 }
636         /* else the cookie is assumed to have 
637          * been initialized by the application */
638
639                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
640                 p += s->d1->cookie_len;
641                 msg_len = p - msg;
642
643                 dtls1_set_message_header(s, buf,
644                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
645
646                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
647                 /* number of bytes to write */
648                 s->init_num=p-buf;
649                 s->init_off=0;
650
651                 /* buffer the message to handle re-xmits */
652                 dtls1_buffer_message(s, 0);
653                 }
654
655         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
656         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
657         }
658
659 int dtls1_send_server_hello(SSL *s)
660         {
661         unsigned char *buf;
662         unsigned char *p,*d;
663         int i;
664         unsigned int sl;
665         unsigned long l,Time;
666
667         if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
668                 {
669                 buf=(unsigned char *)s->init_buf->data;
670                 p=s->s3->server_random;
671                 Time=(unsigned long)time(NULL);                 /* Time */
672                 l2n(Time,p);
673                 RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-sizeof(Time));
674                 /* Do the message type and length last */
675                 d=p= &(buf[DTLS1_HM_HEADER_LENGTH]);
676
677                 *(p++)=s->version>>8;
678                 *(p++)=s->version&0xff;
679
680                 /* Random stuff */
681                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
682                 p+=SSL3_RANDOM_SIZE;
683
684                 /* now in theory we have 3 options to sending back the
685                  * session id.  If it is a re-use, we send back the
686                  * old session-id, if it is a new session, we send
687                  * back the new session-id or we send back a 0 length
688                  * session-id if we want it to be single use.
689                  * Currently I will not implement the '0' length session-id
690                  * 12-Jan-98 - I'll now support the '0' length stuff.
691                  */
692                 if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
693                         s->session->session_id_length=0;
694
695                 sl=s->session->session_id_length;
696                 if (sl > sizeof s->session->session_id)
697                         {
698                         SSLerr(SSL_F_DTLS1_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
699                         return -1;
700                         }
701                 *(p++)=sl;
702                 memcpy(p,s->session->session_id,sl);
703                 p+=sl;
704
705                 /* put the cipher */
706                 i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
707                 p+=i;
708
709                 /* put the compression method */
710 #ifdef OPENSSL_NO_COMP
711                 *(p++)=0;
712 #else
713                 if (s->s3->tmp.new_compression == NULL)
714                         *(p++)=0;
715                 else
716                         *(p++)=s->s3->tmp.new_compression->id;
717 #endif
718
719                 /* do the header */
720                 l=(p-d);
721                 d=buf;
722
723                 d = dtls1_set_message_header(s, d, SSL3_MT_SERVER_HELLO, l, 0, l);
724
725                 s->state=SSL3_ST_CW_CLNT_HELLO_B;
726                 /* number of bytes to write */
727                 s->init_num=p-buf;
728                 s->init_off=0;
729
730                 /* buffer the message to handle re-xmits */
731                 dtls1_buffer_message(s, 0);
732                 }
733
734         /* SSL3_ST_CW_CLNT_HELLO_B */
735         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
736         }
737
738 int dtls1_send_server_done(SSL *s)
739         {
740         unsigned char *p;
741
742         if (s->state == SSL3_ST_SW_SRVR_DONE_A)
743                 {
744                 p=(unsigned char *)s->init_buf->data;
745
746                 /* do the header */
747                 p = dtls1_set_message_header(s, p, SSL3_MT_SERVER_DONE, 0, 0, 0);
748
749                 s->state=SSL3_ST_SW_SRVR_DONE_B;
750                 /* number of bytes to write */
751                 s->init_num=DTLS1_HM_HEADER_LENGTH;
752                 s->init_off=0;
753
754                 /* buffer the message to handle re-xmits */
755                 dtls1_buffer_message(s, 0);
756                 }
757
758         /* SSL3_ST_CW_CLNT_HELLO_B */
759         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
760         }
761
762 int dtls1_send_server_key_exchange(SSL *s)
763         {
764 #ifndef OPENSSL_NO_RSA
765         unsigned char *q;
766         int j,num;
767         RSA *rsa;
768         unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
769         unsigned int u;
770 #endif
771 #ifndef OPENSSL_NO_DH
772         DH *dh=NULL,*dhp;
773 #endif
774         EVP_PKEY *pkey;
775         unsigned char *p,*d;
776         int al,i;
777         unsigned long type;
778         int n;
779         CERT *cert;
780         BIGNUM *r[4];
781         int nr[4],kn;
782         BUF_MEM *buf;
783         EVP_MD_CTX md_ctx;
784
785         EVP_MD_CTX_init(&md_ctx);
786         if (s->state == SSL3_ST_SW_KEY_EXCH_A)
787                 {
788                 type=s->s3->tmp.new_cipher->algorithm_mkey;
789                 cert=s->cert;
790
791                 buf=s->init_buf;
792
793                 r[0]=r[1]=r[2]=r[3]=NULL;
794                 n=0;
795 #ifndef OPENSSL_NO_RSA
796                 if (type & SSL_kRSA)
797                         {
798                         rsa=cert->rsa_tmp;
799                         if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
800                                 {
801                                 rsa=s->cert->rsa_tmp_cb(s,
802                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
803                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
804                                 if(rsa == NULL)
805                                 {
806                                         al=SSL_AD_HANDSHAKE_FAILURE;
807                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
808                                         goto f_err;
809                                 }
810                                 RSA_up_ref(rsa);
811                                 cert->rsa_tmp=rsa;
812                                 }
813                         if (rsa == NULL)
814                                 {
815                                 al=SSL_AD_HANDSHAKE_FAILURE;
816                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
817                                 goto f_err;
818                                 }
819                         r[0]=rsa->n;
820                         r[1]=rsa->e;
821                         s->s3->tmp.use_rsa_tmp=1;
822                         }
823                 else
824 #endif
825 #ifndef OPENSSL_NO_DH
826                         if (type & SSL_kEDH)
827                         {
828                         dhp=cert->dh_tmp;
829                         if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
830                                 dhp=s->cert->dh_tmp_cb(s,
831                                       SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
832                                       SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
833                         if (dhp == NULL)
834                                 {
835                                 al=SSL_AD_HANDSHAKE_FAILURE;
836                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
837                                 goto f_err;
838                                 }
839
840                         if (s->s3->tmp.dh != NULL)
841                                 {
842                                 DH_free(dh);
843                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
844                                 goto err;
845                                 }
846
847                         if ((dh=DHparams_dup(dhp)) == NULL)
848                                 {
849                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
850                                 goto err;
851                                 }
852
853                         s->s3->tmp.dh=dh;
854                         if ((dhp->pub_key == NULL ||
855                              dhp->priv_key == NULL ||
856                              (s->options & SSL_OP_SINGLE_DH_USE)))
857                                 {
858                                 if(!DH_generate_key(dh))
859                                     {
860                                     SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,
861                                            ERR_R_DH_LIB);
862                                     goto err;
863                                     }
864                                 }
865                         else
866                                 {
867                                 dh->pub_key=BN_dup(dhp->pub_key);
868                                 dh->priv_key=BN_dup(dhp->priv_key);
869                                 if ((dh->pub_key == NULL) ||
870                                         (dh->priv_key == NULL))
871                                         {
872                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
873                                         goto err;
874                                         }
875                                 }
876                         r[0]=dh->p;
877                         r[1]=dh->g;
878                         r[2]=dh->pub_key;
879                         }
880                 else 
881 #endif
882                         {
883                         al=SSL_AD_HANDSHAKE_FAILURE;
884                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
885                         goto f_err;
886                         }
887                 for (i=0; r[i] != NULL; i++)
888                         {
889                         nr[i]=BN_num_bytes(r[i]);
890                         n+=2+nr[i];
891                         }
892
893                 if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL))
894                         {
895                         if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
896                                 == NULL)
897                                 {
898                                 al=SSL_AD_DECODE_ERROR;
899                                 goto f_err;
900                                 }
901                         kn=EVP_PKEY_size(pkey);
902                         }
903                 else
904                         {
905                         pkey=NULL;
906                         kn=0;
907                         }
908
909                 if (!BUF_MEM_grow_clean(buf,n+DTLS1_HM_HEADER_LENGTH+kn))
910                         {
911                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
912                         goto err;
913                         }
914                 d=(unsigned char *)s->init_buf->data;
915                 p= &(d[DTLS1_HM_HEADER_LENGTH]);
916
917                 for (i=0; r[i] != NULL; i++)
918                         {
919                         s2n(nr[i],p);
920                         BN_bn2bin(r[i],p);
921                         p+=nr[i];
922                         }
923
924                 /* not anonymous */
925                 if (pkey != NULL)
926                         {
927                         /* n is the length of the params, they start at
928                          * &(d[DTLS1_HM_HEADER_LENGTH]) and p points to the space
929                          * at the end. */
930 #ifndef OPENSSL_NO_RSA
931                         if (pkey->type == EVP_PKEY_RSA)
932                                 {
933                                 q=md_buf;
934                                 j=0;
935                                 for (num=2; num > 0; num--)
936                                         {
937                                         EVP_DigestInit_ex(&md_ctx,(num == 2)
938                                                 ?s->ctx->md5:s->ctx->sha1, NULL);
939                                         EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
940                                         EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
941                                         EVP_DigestUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
942                                         EVP_DigestFinal_ex(&md_ctx,q,
943                                                 (unsigned int *)&i);
944                                         q+=i;
945                                         j+=i;
946                                         }
947                                 if (RSA_sign(NID_md5_sha1, md_buf, j,
948                                         &(p[2]), &u, pkey->pkey.rsa) <= 0)
949                                         {
950                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
951                                         goto err;
952                                         }
953                                 s2n(u,p);
954                                 n+=u+2;
955                                 }
956                         else
957 #endif
958 #if !defined(OPENSSL_NO_DSA)
959                                 if (pkey->type == EVP_PKEY_DSA)
960                                 {
961                                 /* lets do DSS */
962                                 EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
963                                 EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
964                                 EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
965                                 EVP_SignUpdate(&md_ctx,&(d[DTLS1_HM_HEADER_LENGTH]),n);
966                                 if (!EVP_SignFinal(&md_ctx,&(p[2]),
967                                         (unsigned int *)&i,pkey))
968                                         {
969                                         SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
970                                         goto err;
971                                         }
972                                 s2n(i,p);
973                                 n+=i+2;
974                                 }
975                         else
976 #endif
977                                 {
978                                 /* Is this error check actually needed? */
979                                 al=SSL_AD_HANDSHAKE_FAILURE;
980                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
981                                 goto f_err;
982                                 }
983                         }
984
985                 d = dtls1_set_message_header(s, d,
986                         SSL3_MT_SERVER_KEY_EXCHANGE, n, 0, n);
987
988                 /* we should now have things packed up, so lets send
989                  * it off */
990                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
991                 s->init_off=0;
992
993                 /* buffer the message to handle re-xmits */
994                 dtls1_buffer_message(s, 0);
995                 }
996
997         s->state = SSL3_ST_SW_KEY_EXCH_B;
998         EVP_MD_CTX_cleanup(&md_ctx);
999         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1000 f_err:
1001         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1002 err:
1003         EVP_MD_CTX_cleanup(&md_ctx);
1004         return(-1);
1005         }
1006
1007 int dtls1_send_certificate_request(SSL *s)
1008         {
1009         unsigned char *p,*d;
1010         int i,j,nl,off,n;
1011         STACK_OF(X509_NAME) *sk=NULL;
1012         X509_NAME *name;
1013         BUF_MEM *buf;
1014         unsigned int msg_len;
1015
1016         if (s->state == SSL3_ST_SW_CERT_REQ_A)
1017                 {
1018                 buf=s->init_buf;
1019
1020                 d=p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
1021
1022                 /* get the list of acceptable cert types */
1023                 p++;
1024                 n=ssl3_get_req_cert_type(s,p);
1025                 d[0]=n;
1026                 p+=n;
1027                 n++;
1028
1029                 off=n;
1030                 p+=2;
1031                 n+=2;
1032
1033                 sk=SSL_get_client_CA_list(s);
1034                 nl=0;
1035                 if (sk != NULL)
1036                         {
1037                         for (i=0; i<sk_X509_NAME_num(sk); i++)
1038                                 {
1039                                 name=sk_X509_NAME_value(sk,i);
1040                                 j=i2d_X509_NAME(name,NULL);
1041                                 if (!BUF_MEM_grow_clean(buf,DTLS1_HM_HEADER_LENGTH+n+j+2))
1042                                         {
1043                                         SSLerr(SSL_F_DTLS1_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
1044                                         goto err;
1045                                         }
1046                                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+n]);
1047                                 if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
1048                                         {
1049                                         s2n(j,p);
1050                                         i2d_X509_NAME(name,&p);
1051                                         n+=2+j;
1052                                         nl+=2+j;
1053                                         }
1054                                 else
1055                                         {
1056                                         d=p;
1057                                         i2d_X509_NAME(name,&p);
1058                                         j-=2; s2n(j,d); j+=2;
1059                                         n+=j;
1060                                         nl+=j;
1061                                         }
1062                                 }
1063                         }
1064                 /* else no CA names */
1065                 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH+off]);
1066                 s2n(nl,p);
1067
1068                 d=(unsigned char *)buf->data;
1069                 *(d++)=SSL3_MT_CERTIFICATE_REQUEST;
1070                 l2n3(n,d);
1071                 s2n(s->d1->handshake_write_seq,d);
1072                 s->d1->handshake_write_seq++;
1073
1074                 /* we should now have things packed up, so lets send
1075                  * it off */
1076
1077                 s->init_num=n+DTLS1_HM_HEADER_LENGTH;
1078                 s->init_off=0;
1079 #ifdef NETSCAPE_HANG_BUG
1080 /* XXX: what to do about this? */
1081                 p=(unsigned char *)s->init_buf->data + s->init_num;
1082
1083                 /* do the header */
1084                 *(p++)=SSL3_MT_SERVER_DONE;
1085                 *(p++)=0;
1086                 *(p++)=0;
1087                 *(p++)=0;
1088                 s->init_num += 4;
1089 #endif
1090
1091                 /* XDTLS:  set message header ? */
1092                 msg_len = s->init_num - DTLS1_HM_HEADER_LENGTH;
1093                 dtls1_set_message_header(s, (void *)s->init_buf->data,
1094                         SSL3_MT_CERTIFICATE_REQUEST, msg_len, 0, msg_len);
1095
1096                 /* buffer the message to handle re-xmits */
1097                 dtls1_buffer_message(s, 0);
1098
1099                 s->state = SSL3_ST_SW_CERT_REQ_B;
1100                 }
1101
1102         /* SSL3_ST_SW_CERT_REQ_B */
1103         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1104 err:
1105         return(-1);
1106         }
1107
1108 int dtls1_send_server_certificate(SSL *s)
1109         {
1110         unsigned long l;
1111         X509 *x;
1112
1113         if (s->state == SSL3_ST_SW_CERT_A)
1114                 {
1115                 x=ssl_get_server_send_cert(s);
1116                 if (x == NULL)
1117                         {
1118                         /* VRS: allow null cert if auth == KRB5 */
1119                         if ((s->s3->tmp.new_cipher->algorithm_mkey != SSL_kKRB5) ||
1120                             (s->s3->tmp.new_cipher->algorithm_auth != SSL_aKRB5))
1121                                 {
1122                                 SSLerr(SSL_F_DTLS1_SEND_SERVER_CERTIFICATE,ERR_R_INTERNAL_ERROR);
1123                                 return(0);
1124                                 }
1125                         }
1126
1127                 l=dtls1_output_cert_chain(s,x);
1128                 s->state=SSL3_ST_SW_CERT_B;
1129                 s->init_num=(int)l;
1130                 s->init_off=0;
1131
1132                 /* buffer the message to handle re-xmits */
1133                 dtls1_buffer_message(s, 0);
1134                 }
1135
1136         /* SSL3_ST_SW_CERT_B */
1137         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
1138         }