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         unsigned long alg_k;
 151         int ret= -1;
 152         int new_state,state,skip=0;
 153         int listen;
 154 #ifndef OPENSSL_NO_SCTP
 155         unsigned char sctpauthkey[64];
 156         char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
 157 #endif
 158
 159         RAND_add(&Time,sizeof(Time),0);
 160         ERR_clear_error();
 161         clear_sys_error();
 162
 163         if (s->info_callback != NULL)
 164                 cb=s->info_callback;
 165         else if (s->ctx->info_callback != NULL)
 166                 cb=s->ctx->info_callback;
 167
 168         listen = s->d1->listen;
 169
 170         /* init things to blank */
 171         s->in_handshake++;
 172         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 173
 174         s->d1->listen = listen;
 175 #ifndef OPENSSL_NO_SCTP
 176         /* Notify SCTP BIO socket to enter handshake
 177          * mode and prevent stream identifier other
 178          * than 0. Will be ignored if no SCTP is used.
 179          */
 180         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 181 #endif
 182
 183         if (s->cert == NULL)
 184                 {
 185                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
 186                 return(-1);
 187                 }
 188
 189 #ifndef OPENSSL_NO_HEARTBEATS
 190         /* If we're awaiting a HeartbeatResponse, pretend we
 191          * already got and don't await it anymore, because
 192          * Heartbeats don't make sense during handshakes anyway.
 193          */
 194         if (s->tlsext_hb_pending)
 195                 {
 196                 dtls1_stop_timer(s);
 197                 s->tlsext_hb_pending = 0;
 198                 s->tlsext_hb_seq++;
 199                 }
 200 #endif
 201
 202         for (;;)
 203                 {
 204                 state=s->state;
 205
 206                 switch (s->state)
 207                         {
 208                 case SSL_ST_RENEGOTIATE:
 209                         s->renegotiate=1;
 210                         /* s->state=SSL_ST_ACCEPT; */
 211
 212                 case SSL_ST_BEFORE:
 213                 case SSL_ST_ACCEPT:
 214                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
 215                 case SSL_ST_OK|SSL_ST_ACCEPT:
 216
 217                         s->server=1;
 218                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 219
 220                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
 221                                 {
 222                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
 223                                 return -1;
 224                                 }
 225                         s->type=SSL_ST_ACCEPT;
 226
 227                         if (s->init_buf == NULL)
 228                                 {
 229                                 if ((buf=BUF_MEM_new()) == NULL)
 230                                         {
 231                                         ret= -1;
 232                                         goto end;
 233                                         }
 234                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 235                                         {
 236                                         ret= -1;
 237                                         goto end;
 238                                         }
 239                                 s->init_buf=buf;
 240                                 }
 241
 242                         if (!ssl3_setup_buffers(s))
 243                                 {
 244                                 ret= -1;
 245                                 goto end;
 246                                 }
 247
 248                         s->init_num=0;
 249
 250                         if (s->state != SSL_ST_RENEGOTIATE)
 251                                 {
 252                                 /* Ok, we now need to push on a buffering BIO so that
 253                                  * the output is sent in a way that TCP likes :-)
 254                                  * ...but not with SCTP :-)
 255                                  */
 256 #ifndef OPENSSL_NO_SCTP
 257                                 if (!BIO_dgram_is_sctp(SSL_get_wbio(s)))
 258 #endif
 259                                         if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
 260
 261                                 ssl3_init_finished_mac(s);
 262                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
 263                                 s->ctx->stats.sess_accept++;
 264                                 }
 265                         else
 266                                 {
 267                                 /* s->state == SSL_ST_RENEGOTIATE,
 268                                  * we will just send a HelloRequest */
 269                                 s->ctx->stats.sess_accept_renegotiate++;
 270                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
 271                                 }
 272
 273                         break;
 274
 275                 case SSL3_ST_SW_HELLO_REQ_A:
 276                 case SSL3_ST_SW_HELLO_REQ_B:
 277
 278                         s->shutdown=0;
 279                         dtls1_start_timer(s);
 280                         ret=ssl3_send_hello_request(s);
 281                         if (ret <= 0) goto end;
 282                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
 283                         s->state=SSL3_ST_SW_FLUSH;
 284                         s->init_num=0;
 285
 286                         ssl3_init_finished_mac(s);
 287                         break;
 288
 289                 case SSL3_ST_SW_HELLO_REQ_C:
 290                         s->state=SSL_ST_OK;
 291                         break;
 292
 293                 case SSL3_ST_SR_CLNT_HELLO_A:
 294                 case SSL3_ST_SR_CLNT_HELLO_B:
 295                 case SSL3_ST_SR_CLNT_HELLO_C:
 296
 297                         s->shutdown=0;
 298                         ret=ssl3_get_client_hello(s);
 299                         if (ret <= 0) goto end;
 300                         dtls1_stop_timer(s);
 301
 302                         if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
 303                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
 304                         else
 305                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
 306
 307                         s->init_num=0;
 308
 309                         /* Reflect ClientHello sequence to remain stateless while listening */
 310                         if (listen)
 311                                 {
 312                                 memcpy(s->s3->write_sequence, s->s3->read_sequence, sizeof(s->s3->write_sequence));
 313                                 }
 314
 315                         /* If we're just listening, stop here */
 316                         if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A)
 317                                 {
 318                                 ret = 2;
 319                                 s->d1->listen = 0;
 320                                 /* Set expected sequence numbers
 321                                  * to continue the handshake.
 322                                  */
 323                                 s->d1->handshake_read_seq = 2;
 324                                 s->d1->handshake_write_seq = 1;
 325                                 s->d1->next_handshake_write_seq = 1;
 326                                 goto end;
 327                                 }
 328
 329                         break;
 330
 331                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
 332                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
 333
 334                         ret = dtls1_send_hello_verify_request(s);
 335                         if ( ret <= 0) goto end;
 336                         s->state=SSL3_ST_SW_FLUSH;
 337                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
 338
 339                         /* HelloVerifyRequest resets Finished MAC */
 340                         if (s->version != DTLS1_BAD_VER)
 341                                 ssl3_init_finished_mac(s);
 342                         break;
 343
 344 #ifndef OPENSSL_NO_SCTP
 345                 case DTLS1_SCTP_ST_SR_READ_SOCK:
 346
 347                         if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 348                                 {
 349                                 s->s3->in_read_app_data=2;
 350                                 s->rwstate=SSL_READING;
 351                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 352                                 BIO_set_retry_read(SSL_get_rbio(s));
 353                                 ret = -1;
 354                                 goto end;
 355                                 }
 356
 357                         s->state=SSL3_ST_SR_FINISHED_A;
 358                         break;
 359
 360                 case DTLS1_SCTP_ST_SW_WRITE_SOCK:
 361                         ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
 362                         if (ret < 0) goto end;
 363
 364                         if (ret == 0)
 365                                 {
 366                                 if (s->d1->next_state != SSL_ST_OK)
 367                                         {
 368                                         s->s3->in_read_app_data=2;
 369                                         s->rwstate=SSL_READING;
 370                                         BIO_clear_retry_flags(SSL_get_rbio(s));
 371                                         BIO_set_retry_read(SSL_get_rbio(s));
 372                                         ret = -1;
 373                                         goto end;
 374                                         }
 375                                 }
 376
 377                         s->state=s->d1->next_state;
 378                         break;
 379 #endif
 380
 381                 case SSL3_ST_SW_SRVR_HELLO_A:
 382                 case SSL3_ST_SW_SRVR_HELLO_B:
 383                         s->renegotiate = 2;
 384                         dtls1_start_timer(s);
 385                         ret=ssl3_send_server_hello(s);
 386                         if (ret <= 0) goto end;
 387
 388                         if (s->hit)
 389                                 {
 390 #ifndef OPENSSL_NO_SCTP
 391                                 /* Add new shared key for SCTP-Auth,
 392                                  * will be ignored if no SCTP used.
 393                                  */
 394                                 snprintf((char*) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 395                                          DTLS1_SCTP_AUTH_LABEL);
 396
 397                                 SSL_export_keying_material(s, sctpauthkey,
 398                                                            sizeof(sctpauthkey), labelbuffer,
 399                                                            sizeof(labelbuffer), NULL, 0, 0);
 400
 401                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 402                          sizeof(sctpauthkey), sctpauthkey);
 403 #endif
 404 #ifndef OPENSSL_NO_TLSEXT
 405                                 if (s->tlsext_ticket_expected)
 406                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
 407                                 else
 408                                         s->state=SSL3_ST_SW_CHANGE_A;
 409 #else
 410                                 s->state=SSL3_ST_SW_CHANGE_A;
 411 #endif
 412                                 }
 413                         else
 414                                 s->state=SSL3_ST_SW_CERT_A;
 415                         s->init_num=0;
 416                         break;
 417
 418                 case SSL3_ST_SW_CERT_A:
 419                 case SSL3_ST_SW_CERT_B:
 420                         /* Check if it is anon DH or normal PSK */
 421                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
 422                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 423                                 {
 424                                 dtls1_start_timer(s);
 425                                 ret=ssl3_send_server_certificate(s);
 426                                 if (ret <= 0) goto end;
 427 #ifndef OPENSSL_NO_TLSEXT
 428                                 if (s->tlsext_status_expected)
 429                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
 430                                 else
 431                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 432                                 }
 433                         else
 434                                 {
 435                                 skip = 1;
 436                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
 437                                 }
 438 #else
 439                                 }
 440                         else
 441                                 skip=1;
 442
 443                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 444 #endif
 445                         s->init_num=0;
 446                         break;
 447
 448                 case SSL3_ST_SW_KEY_EXCH_A:
 449                 case SSL3_ST_SW_KEY_EXCH_B:
 450                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
 451
 452                         /* clear this, it may get reset by
 453                          * send_server_key_exchange */
 454                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
 455 #ifndef OPENSSL_NO_KRB5
 456                                 && !(alg_k & SSL_kKRB5)
 457 #endif /* OPENSSL_NO_KRB5 */
 458                                 )
 459                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
 460                                  * even when forbidden by protocol specs
 461                                  * (handshake may fail as clients are not required to
 462                                  * be able to handle this) */
 463                                 s->s3->tmp.use_rsa_tmp=1;
 464                         else
 465                                 s->s3->tmp.use_rsa_tmp=0;
 466
 467                         /* only send if a DH key exchange or
 468                          * RSA but we have a sign only certificate */
 469                         if (s->s3->tmp.use_rsa_tmp
 470                         /* PSK: send ServerKeyExchange if PSK identity
 471                          * hint if provided */
 472 #ifndef OPENSSL_NO_PSK
 473                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
 474 #endif
 475                             || (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
 476                             || (alg_k & SSL_kEECDH)
 477                             || ((alg_k & SSL_kRSA)
 478                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
 479                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
 480                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
 481                                         )
 482                                     )
 483                                 )
 484                             )
 485                                 {
 486                                 dtls1_start_timer(s);
 487                                 ret=ssl3_send_server_key_exchange(s);
 488                                 if (ret <= 0) goto end;
 489                                 }
 490                         else
 491                                 skip=1;
 492
 493                         s->state=SSL3_ST_SW_CERT_REQ_A;
 494                         s->init_num=0;
 495                         break;
 496
 497                 case SSL3_ST_SW_CERT_REQ_A:
 498                 case SSL3_ST_SW_CERT_REQ_B:
 499                         if (/* don't request cert unless asked for it: */
 500                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
 501                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
 502                                  * don't request cert during re-negotiation: */
 503                                 ((s->session->peer != NULL) &&
 504                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
 505                                 /* never request cert in anonymous ciphersuites
 506                                  * (see section "Certificate request" in SSL 3 drafts
 507                                  * and in RFC 2246): */
 508                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
 509                                  /* ... except when the application insists on verification
 510                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
 511                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
 512                                  /* never request cert in Kerberos ciphersuites */
 513                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
 514                                 /* With normal PSK Certificates and
 515                                  * Certificate Requests are omitted */
 516                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 517                                 {
 518                                 /* no cert request */
 519                                 skip=1;
 520                                 s->s3->tmp.cert_request=0;
 521                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 522 #ifndef OPENSSL_NO_SCTP
 523                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 524                                         {
 525                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 526                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 527                                         }
 528 #endif
 529                                 }
 530                         else
 531                                 {
 532                                 s->s3->tmp.cert_request=1;
 533                                 dtls1_start_timer(s);
 534                                 ret=ssl3_send_certificate_request(s);
 535                                 if (ret <= 0) goto end;
 536 #ifndef NETSCAPE_HANG_BUG
 537                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 538 #ifndef OPENSSL_NO_SCTP
 539                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 540                                         {
 541                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 542                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 543                                         }
 544 #endif
 545 #else
 546                                 s->state=SSL3_ST_SW_FLUSH;
 547                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 548 #ifndef OPENSSL_NO_SCTP
 549                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 550                                         {
 551                                         s->d1->next_state = s->s3->tmp.next_state;
 552                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 553                                         }
 554 #endif
 555 #endif
 556                                 s->init_num=0;
 557                                 }
 558                         break;
 559
 560                 case SSL3_ST_SW_SRVR_DONE_A:
 561                 case SSL3_ST_SW_SRVR_DONE_B:
 562                         dtls1_start_timer(s);
 563                         ret=ssl3_send_server_done(s);
 564                         if (ret <= 0) goto end;
 565                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 566                         s->state=SSL3_ST_SW_FLUSH;
 567                         s->init_num=0;
 568                         break;
 569
 570                 case SSL3_ST_SW_FLUSH:
 571                         s->rwstate=SSL_WRITING;
 572                         if (BIO_flush(s->wbio) <= 0)
 573                                 {
 574                                 /* If the write error was fatal, stop trying */
 575                                 if (!BIO_should_retry(s->wbio))
 576                                         {
 577                                         s->rwstate=SSL_NOTHING;
 578                                         s->state=s->s3->tmp.next_state;
 579                                         }
 580
 581                                 ret= -1;
 582                                 goto end;
 583                                 }
 584                         s->rwstate=SSL_NOTHING;
 585                         s->state=s->s3->tmp.next_state;
 586                         break;
 587
 588                 case SSL3_ST_SR_CERT_A:
 589                 case SSL3_ST_SR_CERT_B:
 590                         /* Check for second client hello (MS SGC) */
 591                         ret = ssl3_check_client_hello(s);
 592                         if (ret <= 0)
 593                                 goto end;
 594                         if (ret == 2)
 595                                 {
 596                                 dtls1_stop_timer(s);
 597                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
 598                                 }
 599                         else {
 600                                 /* could be sent for a DH cert, even if we
 601                                  * have not asked for it :-) */
 602                                 ret=ssl3_get_client_certificate(s);
 603                                 if (ret <= 0) goto end;
 604                                 s->init_num=0;
 605                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
 606                         }
 607                         break;
 608
 609                 case SSL3_ST_SR_KEY_EXCH_A:
 610                 case SSL3_ST_SR_KEY_EXCH_B:
 611                         ret=ssl3_get_client_key_exchange(s);
 612                         if (ret <= 0) goto end;
 613 #ifndef OPENSSL_NO_SCTP
 614                         /* Add new shared key for SCTP-Auth,
 615                          * will be ignored if no SCTP used.
 616                          */
 617                         snprintf((char *) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 618                                  DTLS1_SCTP_AUTH_LABEL);
 619
 620                         SSL_export_keying_material(s, sctpauthkey,
 621                                                    sizeof(sctpauthkey), labelbuffer,
 622                                                    sizeof(labelbuffer), NULL, 0, 0);
 623
 624                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 625                                  sizeof(sctpauthkey), sctpauthkey);
 626 #endif
 627
 628                         s->state=SSL3_ST_SR_CERT_VRFY_A;
 629                         s->init_num=0;
 630
 631                         if (ret == 2)
 632                                 {
 633                                 /* For the ECDH ciphersuites when
 634                                  * the client sends its ECDH pub key in
 635                                  * a certificate, the CertificateVerify
 636                                  * message is not sent.
 637                                  */
 638                                 s->state=SSL3_ST_SR_FINISHED_A;
 639                                 s->init_num = 0;
 640                                 }
 641                         else
 642                                 {
 643                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
 644                                 s->init_num=0;
 645
 646                                 /* We need to get hashes here so if there is
 647                                  * a client cert, it can be verified */
 648                                 s->method->ssl3_enc->cert_verify_mac(s,
 649                                         NID_md5,
 650                                         &(s->s3->tmp.cert_verify_md[0]));
 651                                 s->method->ssl3_enc->cert_verify_mac(s,
 652                                         NID_sha1,
 653                                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
 654                                 }
 655                         break;
 656
 657                 case SSL3_ST_SR_CERT_VRFY_A:
 658                 case SSL3_ST_SR_CERT_VRFY_B:
 659
 660                         s->d1->change_cipher_spec_ok = 1;
 661                         /* we should decide if we expected this one */
 662                         ret=ssl3_get_cert_verify(s);
 663                         if (ret <= 0) goto end;
 664 #ifndef OPENSSL_NO_SCTP
 665                         if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
 666                             state == SSL_ST_RENEGOTIATE)
 667                                 s->state=DTLS1_SCTP_ST_SR_READ_SOCK;
 668                         else
 669 #endif
 670                                 s->state=SSL3_ST_SR_FINISHED_A;
 671                         s->init_num=0;
 672                         break;
 673
 674                 case SSL3_ST_SR_FINISHED_A:
 675                 case SSL3_ST_SR_FINISHED_B:
 676                         s->d1->change_cipher_spec_ok = 1;
 677                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
 678                                 SSL3_ST_SR_FINISHED_B);
 679                         if (ret <= 0) goto end;
 680                         dtls1_stop_timer(s);
 681                         if (s->hit)
 682                                 s->state=SSL_ST_OK;
 683 #ifndef OPENSSL_NO_TLSEXT
 684                         else if (s->tlsext_ticket_expected)
 685                                 s->state=SSL3_ST_SW_SESSION_TICKET_A;
 686 #endif
 687                         else
 688                                 s->state=SSL3_ST_SW_CHANGE_A;
 689                         s->init_num=0;
 690                         break;
 691
 692 #ifndef OPENSSL_NO_TLSEXT
 693                 case SSL3_ST_SW_SESSION_TICKET_A:
 694                 case SSL3_ST_SW_SESSION_TICKET_B:
 695                         ret=ssl3_send_newsession_ticket(s);
 696                         if (ret <= 0) goto end;
 697                         s->state=SSL3_ST_SW_CHANGE_A;
 698                         s->init_num=0;
 699                         break;
 700
 701                 case SSL3_ST_SW_CERT_STATUS_A:
 702                 case SSL3_ST_SW_CERT_STATUS_B:
 703                         ret=ssl3_send_cert_status(s);
 704                         if (ret <= 0) goto end;
 705                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 706                         s->init_num=0;
 707                         break;
 708
 709 #endif
 710
 711                 case SSL3_ST_SW_CHANGE_A:
 712                 case SSL3_ST_SW_CHANGE_B:
 713
 714                         s->session->cipher=s->s3->tmp.new_cipher;
 715                         if (!s->method->ssl3_enc->setup_key_block(s))
 716                                 { ret= -1; goto end; }
 717
 718                         ret=dtls1_send_change_cipher_spec(s,
 719                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
 720
 721                         if (ret <= 0) goto end;
 722
 723 #ifndef OPENSSL_NO_SCTP
 724                         /* Change to new shared key of SCTP-Auth,
 725                          * will be ignored if no SCTP used.
 726                          */
 727                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
 728 #endif
 729
 730                         s->state=SSL3_ST_SW_FINISHED_A;
 731                         s->init_num=0;
 732
 733                         if (!s->method->ssl3_enc->change_cipher_state(s,
 734                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
 735                                 {
 736                                 ret= -1;
 737                                 goto end;
 738                                 }
 739
 740                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
 741                         break;
 742
 743                 case SSL3_ST_SW_FINISHED_A:
 744                 case SSL3_ST_SW_FINISHED_B:
 745                         ret=ssl3_send_finished(s,
 746                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
 747                                 s->method->ssl3_enc->server_finished_label,
 748                                 s->method->ssl3_enc->server_finished_label_len);
 749                         if (ret <= 0) goto end;
 750                         s->state=SSL3_ST_SW_FLUSH;
 751                         if (s->hit)
 752                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
 753                         else
 754                                 {
 755                                 s->s3->tmp.next_state=SSL_ST_OK;
 756 #ifndef OPENSSL_NO_SCTP
 757                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 758                                         {
 759                                         s->d1->next_state = s->s3->tmp.next_state;
 760                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 761                                         }
 762 #endif
 763                                 }
 764                         s->init_num=0;
 765                         break;
 766
 767                 case SSL_ST_OK:
 768                         /* clean a few things up */
 769                         ssl3_cleanup_key_block(s);
 770
 771 #if 0
 772                         BUF_MEM_free(s->init_buf);
 773                         s->init_buf=NULL;
 774 #endif
 775
 776                         /* remove buffering on output */
 777                         ssl_free_wbio_buffer(s);
 778
 779                         s->init_num=0;
 780
 781                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
 782                                 {
 783                                 s->renegotiate=0;
 784                                 s->new_session=0;
 785
 786                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
 787
 788                                 s->ctx->stats.sess_accept_good++;
 789                                 /* s->server=1; */
 790                                 s->handshake_func=dtls1_accept;
 791
 792                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
 793                                 }
 794
 795                         ret = 1;
 796
 797                         /* done handshaking, next message is client hello */
 798                         s->d1->handshake_read_seq = 0;
 799                         /* next message is server hello */
 800                         s->d1->handshake_write_seq = 0;
 801                         s->d1->next_handshake_write_seq = 0;
 802                         goto end;
 803                         /* break; */
 804
 805                 default:
 806                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
 807                         ret= -1;
 808                         goto end;
 809                         /* break; */
 810                         }
 811
 812                 if (!s->s3->tmp.reuse_message && !skip)
 813                         {
 814                         if (s->debug)
 815                                 {
 816                                 if ((ret=BIO_flush(s->wbio)) <= 0)
 817                                         goto end;
 818                                 }
 819
 820
 821                         if ((cb != NULL) && (s->state != state))
 822                                 {
 823                                 new_state=s->state;
 824                                 s->state=state;
 825                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
 826                                 s->state=new_state;
 827                                 }
 828                         }
 829                 skip=0;
 830                 }
 831 end:
 832         /* BIO_flush(s->wbio); */
 833
 834         s->in_handshake--;
 835 #ifndef OPENSSL_NO_SCTP
 836                 /* Notify SCTP BIO socket to leave handshake
 837                  * mode and prevent stream identifier other
 838                  * than 0. Will be ignored if no SCTP is used.
 839                  */
 840                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 841 #endif
 842
 843         if (cb != NULL)
 844                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
 845         return(ret);
 846         }
 847
 848 int dtls1_send_hello_verify_request(SSL *s)
 849         {
 850         unsigned int msg_len;
 851         unsigned char *msg, *buf, *p;
 852
 853         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
 854                 {
 855                 buf = (unsigned char *)s->init_buf->data;
 856
 857                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
 858                 *(p++) = s->version >> 8;
 859                 *(p++) = s->version & 0xFF;
 860
 861                 if (s->ctx->app_gen_cookie_cb == NULL ||
 862                      s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
 863                          &(s->d1->cookie_len)) == 0)
 864                         {
 865                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
 866                         return 0;
 867                         }
 868
 869                 *(p++) = (unsigned char) s->d1->cookie_len;
 870                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
 871                 p += s->d1->cookie_len;
 872                 msg_len = p - msg;
 873
 874                 dtls1_set_message_header(s, buf,
 875                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
 876
 877                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
 878                 /* number of bytes to write */
 879                 s->init_num=p-buf;
 880                 s->init_off=0;
 881                 }
 882
 883         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
 884         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
 885         }