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 if (ver == DTLS1_2_VERSION)
 137                 return(DTLSv1_2_server_method());
 138         else
 139                 return(NULL);
 140         }
 141
 142 IMPLEMENT_dtls1_meth_func(DTLS1_VERSION,
 143                         DTLSv1_server_method,
 144                         dtls1_accept,
 145                         ssl_undefined_function,
 146                         dtls1_get_server_method,
 147                         DTLSv1_enc_data)
 148
 149 IMPLEMENT_dtls1_meth_func(DTLS1_2_VERSION,
 150                         DTLSv1_2_server_method,
 151                         dtls1_accept,
 152                         ssl_undefined_function,
 153                         dtls1_get_server_method,
 154                         DTLSv1_2_enc_data)
 155
 156 int dtls1_accept(SSL *s)
 157         {
 158         BUF_MEM *buf;
 159         unsigned long Time=(unsigned long)time(NULL);
 160         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 161         unsigned long alg_k;
 162         int ret= -1;
 163         int new_state,state,skip=0;
 164         int listen;
 165 #ifndef OPENSSL_NO_SCTP
 166         unsigned char sctpauthkey[64];
 167         char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
 168 #endif
 169
 170         RAND_add(&Time,sizeof(Time),0);
 171         ERR_clear_error();
 172         clear_sys_error();
 173
 174         if (s->info_callback != NULL)
 175                 cb=s->info_callback;
 176         else if (s->ctx->info_callback != NULL)
 177                 cb=s->ctx->info_callback;
 178
 179         listen = s->d1->listen;
 180
 181         /* init things to blank */
 182         s->in_handshake++;
 183         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 184
 185         s->d1->listen = listen;
 186 #ifndef OPENSSL_NO_SCTP
 187         /* Notify SCTP BIO socket to enter handshake
 188          * mode and prevent stream identifier other
 189          * than 0. Will be ignored if no SCTP is used.
 190          */
 191         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 192 #endif
 193
 194         if (s->cert == NULL)
 195                 {
 196                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
 197                 return(-1);
 198                 }
 199
 200 #ifndef OPENSSL_NO_HEARTBEATS
 201         /* If we're awaiting a HeartbeatResponse, pretend we
 202          * already got and don't await it anymore, because
 203          * Heartbeats don't make sense during handshakes anyway.
 204          */
 205         if (s->tlsext_hb_pending)
 206                 {
 207                 dtls1_stop_timer(s);
 208                 s->tlsext_hb_pending = 0;
 209                 s->tlsext_hb_seq++;
 210                 }
 211 #endif
 212
 213         for (;;)
 214                 {
 215                 state=s->state;
 216
 217                 switch (s->state)
 218                         {
 219                 case SSL_ST_RENEGOTIATE:
 220                         s->renegotiate=1;
 221                         /* s->state=SSL_ST_ACCEPT; */
 222
 223                 case SSL_ST_BEFORE:
 224                 case SSL_ST_ACCEPT:
 225                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
 226                 case SSL_ST_OK|SSL_ST_ACCEPT:
 227
 228                         s->server=1;
 229                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 230
 231                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
 232                                 {
 233                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
 234                                 return -1;
 235                                 }
 236                         s->type=SSL_ST_ACCEPT;
 237
 238                         if (s->init_buf == NULL)
 239                                 {
 240                                 if ((buf=BUF_MEM_new()) == NULL)
 241                                         {
 242                                         ret= -1;
 243                                         goto end;
 244                                         }
 245                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 246                                         {
 247                                         ret= -1;
 248                                         goto end;
 249                                         }
 250                                 s->init_buf=buf;
 251                                 }
 252
 253                         if (!ssl3_setup_buffers(s))
 254                                 {
 255                                 ret= -1;
 256                                 goto end;
 257                                 }
 258
 259                         s->init_num=0;
 260
 261                         if (s->state != SSL_ST_RENEGOTIATE)
 262                                 {
 263                                 /* Ok, we now need to push on a buffering BIO so that
 264                                  * the output is sent in a way that TCP likes :-)
 265                                  * ...but not with SCTP :-)
 266                                  */
 267 #ifndef OPENSSL_NO_SCTP
 268                                 if (!BIO_dgram_is_sctp(SSL_get_wbio(s)))
 269 #endif
 270                                         if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
 271
 272                                 ssl3_init_finished_mac(s);
 273                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
 274                                 s->ctx->stats.sess_accept++;
 275                                 }
 276                         else
 277                                 {
 278                                 /* s->state == SSL_ST_RENEGOTIATE,
 279                                  * we will just send a HelloRequest */
 280                                 s->ctx->stats.sess_accept_renegotiate++;
 281                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
 282                                 }
 283
 284                         break;
 285
 286                 case SSL3_ST_SW_HELLO_REQ_A:
 287                 case SSL3_ST_SW_HELLO_REQ_B:
 288
 289                         s->shutdown=0;
 290                         dtls1_clear_record_buffer(s);
 291                         dtls1_start_timer(s);
 292                         ret=ssl3_send_hello_request(s);
 293                         if (ret <= 0) goto end;
 294                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
 295                         s->state=SSL3_ST_SW_FLUSH;
 296                         s->init_num=0;
 297
 298                         ssl3_init_finished_mac(s);
 299                         break;
 300
 301                 case SSL3_ST_SW_HELLO_REQ_C:
 302                         s->state=SSL_ST_OK;
 303                         break;
 304
 305                 case SSL3_ST_SR_CLNT_HELLO_A:
 306                 case SSL3_ST_SR_CLNT_HELLO_B:
 307                 case SSL3_ST_SR_CLNT_HELLO_C:
 308
 309                         s->shutdown=0;
 310                         ret=ssl3_get_client_hello(s);
 311                         if (ret <= 0) goto end;
 312                         dtls1_stop_timer(s);
 313
 314                         if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
 315                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
 316                         else
 317                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
 318
 319                         s->init_num=0;
 320
 321                         /* Reflect ClientHello sequence to remain stateless while listening */
 322                         if (listen)
 323                                 {
 324                                 memcpy(s->s3->write_sequence, s->s3->read_sequence, sizeof(s->s3->write_sequence));
 325                                 }
 326
 327                         /* If we're just listening, stop here */
 328                         if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A)
 329                                 {
 330                                 ret = 2;
 331                                 s->d1->listen = 0;
 332                                 /* Set expected sequence numbers
 333                                  * to continue the handshake.
 334                                  */
 335                                 s->d1->handshake_read_seq = 2;
 336                                 s->d1->handshake_write_seq = 1;
 337                                 s->d1->next_handshake_write_seq = 1;
 338                                 goto end;
 339                                 }
 340
 341                         break;
 342
 343                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
 344                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
 345
 346                         ret = dtls1_send_hello_verify_request(s);
 347                         if ( ret <= 0) goto end;
 348                         s->state=SSL3_ST_SW_FLUSH;
 349                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
 350
 351                         /* HelloVerifyRequest resets Finished MAC */
 352                         if (s->version != DTLS1_BAD_VER)
 353                                 ssl3_init_finished_mac(s);
 354                         break;
 355
 356 #ifndef OPENSSL_NO_SCTP
 357                 case DTLS1_SCTP_ST_SR_READ_SOCK:
 358
 359                         if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 360                                 {
 361                                 s->s3->in_read_app_data=2;
 362                                 s->rwstate=SSL_READING;
 363                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 364                                 BIO_set_retry_read(SSL_get_rbio(s));
 365                                 ret = -1;
 366                                 goto end;
 367                                 }
 368
 369                         s->state=SSL3_ST_SR_FINISHED_A;
 370                         break;
 371
 372                 case DTLS1_SCTP_ST_SW_WRITE_SOCK:
 373                         ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
 374                         if (ret < 0) goto end;
 375
 376                         if (ret == 0)
 377                                 {
 378                                 if (s->d1->next_state != SSL_ST_OK)
 379                                         {
 380                                         s->s3->in_read_app_data=2;
 381                                         s->rwstate=SSL_READING;
 382                                         BIO_clear_retry_flags(SSL_get_rbio(s));
 383                                         BIO_set_retry_read(SSL_get_rbio(s));
 384                                         ret = -1;
 385                                         goto end;
 386                                         }
 387                                 }
 388
 389                         s->state=s->d1->next_state;
 390                         break;
 391 #endif
 392
 393                 case SSL3_ST_SW_SRVR_HELLO_A:
 394                 case SSL3_ST_SW_SRVR_HELLO_B:
 395                         s->renegotiate = 2;
 396                         dtls1_start_timer(s);
 397                         ret=ssl3_send_server_hello(s);
 398                         if (ret <= 0) goto end;
 399
 400                         if (s->hit)
 401                                 {
 402 #ifndef OPENSSL_NO_SCTP
 403                                 /* Add new shared key for SCTP-Auth,
 404                                  * will be ignored if no SCTP used.
 405                                  */
 406                                 snprintf((char*) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 407                                          DTLS1_SCTP_AUTH_LABEL);
 408
 409                                 SSL_export_keying_material(s, sctpauthkey,
 410                                                            sizeof(sctpauthkey), labelbuffer,
 411                                                            sizeof(labelbuffer), NULL, 0, 0);
 412
 413                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 414                          sizeof(sctpauthkey), sctpauthkey);
 415 #endif
 416 #ifndef OPENSSL_NO_TLSEXT
 417                                 if (s->tlsext_ticket_expected)
 418                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
 419                                 else
 420                                         s->state=SSL3_ST_SW_CHANGE_A;
 421 #else
 422                                 s->state=SSL3_ST_SW_CHANGE_A;
 423 #endif
 424                                 }
 425                         else
 426                                 s->state=SSL3_ST_SW_CERT_A;
 427                         s->init_num=0;
 428                         break;
 429
 430                 case SSL3_ST_SW_CERT_A:
 431                 case SSL3_ST_SW_CERT_B:
 432                         /* Check if it is anon DH or normal PSK */
 433                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
 434                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 435                                 {
 436                                 dtls1_start_timer(s);
 437                                 ret=ssl3_send_server_certificate(s);
 438                                 if (ret <= 0) goto end;
 439 #ifndef OPENSSL_NO_TLSEXT
 440                                 if (s->tlsext_status_expected)
 441                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
 442                                 else
 443                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 444                                 }
 445                         else
 446                                 {
 447                                 skip = 1;
 448                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
 449                                 }
 450 #else
 451                                 }
 452                         else
 453                                 skip=1;
 454
 455                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 456 #endif
 457                         s->init_num=0;
 458                         break;
 459
 460                 case SSL3_ST_SW_KEY_EXCH_A:
 461                 case SSL3_ST_SW_KEY_EXCH_B:
 462                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
 463
 464                         /* clear this, it may get reset by
 465                          * send_server_key_exchange */
 466                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
 467 #ifndef OPENSSL_NO_KRB5
 468                                 && !(alg_k & SSL_kKRB5)
 469 #endif /* OPENSSL_NO_KRB5 */
 470                                 )
 471                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
 472                                  * even when forbidden by protocol specs
 473                                  * (handshake may fail as clients are not required to
 474                                  * be able to handle this) */
 475                                 s->s3->tmp.use_rsa_tmp=1;
 476                         else
 477                                 s->s3->tmp.use_rsa_tmp=0;
 478
 479                         /* only send if a DH key exchange or
 480                          * RSA but we have a sign only certificate */
 481                         if (s->s3->tmp.use_rsa_tmp
 482                         /* PSK: send ServerKeyExchange if PSK identity
 483                          * hint if provided */
 484 #ifndef OPENSSL_NO_PSK
 485                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
 486 #endif
 487                             || (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
 488                             || (alg_k & SSL_kEECDH)
 489                             || ((alg_k & SSL_kRSA)
 490                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
 491                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
 492                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
 493                                         )
 494                                     )
 495                                 )
 496                             )
 497                                 {
 498                                 dtls1_start_timer(s);
 499                                 ret=ssl3_send_server_key_exchange(s);
 500                                 if (ret <= 0) goto end;
 501                                 }
 502                         else
 503                                 skip=1;
 504
 505                         s->state=SSL3_ST_SW_CERT_REQ_A;
 506                         s->init_num=0;
 507                         break;
 508
 509                 case SSL3_ST_SW_CERT_REQ_A:
 510                 case SSL3_ST_SW_CERT_REQ_B:
 511                         if (/* don't request cert unless asked for it: */
 512                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
 513                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
 514                                  * don't request cert during re-negotiation: */
 515                                 ((s->session->peer != NULL) &&
 516                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
 517                                 /* never request cert in anonymous ciphersuites
 518                                  * (see section "Certificate request" in SSL 3 drafts
 519                                  * and in RFC 2246): */
 520                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
 521                                  /* ... except when the application insists on verification
 522                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
 523                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
 524                                  /* never request cert in Kerberos ciphersuites */
 525                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
 526                                 /* With normal PSK Certificates and
 527                                  * Certificate Requests are omitted */
 528                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 529                                 {
 530                                 /* no cert request */
 531                                 skip=1;
 532                                 s->s3->tmp.cert_request=0;
 533                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 534 #ifndef OPENSSL_NO_SCTP
 535                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 536                                         {
 537                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 538                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 539                                         }
 540 #endif
 541                                 }
 542                         else
 543                                 {
 544                                 s->s3->tmp.cert_request=1;
 545                                 dtls1_start_timer(s);
 546                                 ret=ssl3_send_certificate_request(s);
 547                                 if (ret <= 0) goto end;
 548 #ifndef NETSCAPE_HANG_BUG
 549                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 550 #ifndef OPENSSL_NO_SCTP
 551                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 552                                         {
 553                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 554                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 555                                         }
 556 #endif
 557 #else
 558                                 s->state=SSL3_ST_SW_FLUSH;
 559                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 560 #ifndef OPENSSL_NO_SCTP
 561                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 562                                         {
 563                                         s->d1->next_state = s->s3->tmp.next_state;
 564                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 565                                         }
 566 #endif
 567 #endif
 568                                 s->init_num=0;
 569                                 }
 570                         break;
 571
 572                 case SSL3_ST_SW_SRVR_DONE_A:
 573                 case SSL3_ST_SW_SRVR_DONE_B:
 574                         dtls1_start_timer(s);
 575                         ret=ssl3_send_server_done(s);
 576                         if (ret <= 0) goto end;
 577                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 578                         s->state=SSL3_ST_SW_FLUSH;
 579                         s->init_num=0;
 580                         break;
 581
 582                 case SSL3_ST_SW_FLUSH:
 583                         s->rwstate=SSL_WRITING;
 584                         if (BIO_flush(s->wbio) <= 0)
 585                                 {
 586                                 /* If the write error was fatal, stop trying */
 587                                 if (!BIO_should_retry(s->wbio))
 588                                         {
 589                                         s->rwstate=SSL_NOTHING;
 590                                         s->state=s->s3->tmp.next_state;
 591                                         }
 592
 593                                 ret= -1;
 594                                 goto end;
 595                                 }
 596                         s->rwstate=SSL_NOTHING;
 597                         s->state=s->s3->tmp.next_state;
 598                         break;
 599
 600                 case SSL3_ST_SR_CERT_A:
 601                 case SSL3_ST_SR_CERT_B:
 602                         /* Check for second client hello (MS SGC) */
 603                         ret = ssl3_check_client_hello(s);
 604                         if (ret <= 0)
 605                                 goto end;
 606                         if (ret == 2)
 607                                 {
 608                                 dtls1_stop_timer(s);
 609                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
 610                                 }
 611                         else {
 612                                 /* could be sent for a DH cert, even if we
 613                                  * have not asked for it :-) */
 614                                 ret=ssl3_get_client_certificate(s);
 615                                 if (ret <= 0) goto end;
 616                                 s->init_num=0;
 617                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
 618                         }
 619                         break;
 620
 621                 case SSL3_ST_SR_KEY_EXCH_A:
 622                 case SSL3_ST_SR_KEY_EXCH_B:
 623                         ret=ssl3_get_client_key_exchange(s);
 624                         if (ret <= 0) goto end;
 625 #ifndef OPENSSL_NO_SCTP
 626                         /* Add new shared key for SCTP-Auth,
 627                          * will be ignored if no SCTP used.
 628                          */
 629                         snprintf((char *) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 630                                  DTLS1_SCTP_AUTH_LABEL);
 631
 632                         SSL_export_keying_material(s, sctpauthkey,
 633                                                    sizeof(sctpauthkey), labelbuffer,
 634                                                    sizeof(labelbuffer), NULL, 0, 0);
 635
 636                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 637                                  sizeof(sctpauthkey), sctpauthkey);
 638 #endif
 639
 640                         s->state=SSL3_ST_SR_CERT_VRFY_A;
 641                         s->init_num=0;
 642
 643                         if (ret == 2)
 644                                 {
 645                                 /* For the ECDH ciphersuites when
 646                                  * the client sends its ECDH pub key in
 647                                  * a certificate, the CertificateVerify
 648                                  * message is not sent.
 649                                  */
 650                                 s->state=SSL3_ST_SR_FINISHED_A;
 651                                 s->init_num = 0;
 652                                 }
 653                         else
 654                                 {
 655                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
 656                                 s->init_num=0;
 657
 658                                 /* We need to get hashes here so if there is
 659                                  * a client cert, it can be verified */
 660                                 s->method->ssl3_enc->cert_verify_mac(s,
 661                                         NID_md5,
 662                                         &(s->s3->tmp.cert_verify_md[0]));
 663                                 s->method->ssl3_enc->cert_verify_mac(s,
 664                                         NID_sha1,
 665                                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
 666                                 }
 667                         break;
 668
 669                 case SSL3_ST_SR_CERT_VRFY_A:
 670                 case SSL3_ST_SR_CERT_VRFY_B:
 671
 672                         s->d1->change_cipher_spec_ok = 1;
 673                         /* we should decide if we expected this one */
 674                         ret=ssl3_get_cert_verify(s);
 675                         if (ret <= 0) goto end;
 676 #ifndef OPENSSL_NO_SCTP
 677                         if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
 678                             state == SSL_ST_RENEGOTIATE)
 679                                 s->state=DTLS1_SCTP_ST_SR_READ_SOCK;
 680                         else
 681 #endif
 682                                 s->state=SSL3_ST_SR_FINISHED_A;
 683                         s->init_num=0;
 684                         break;
 685
 686                 case SSL3_ST_SR_FINISHED_A:
 687                 case SSL3_ST_SR_FINISHED_B:
 688                         s->d1->change_cipher_spec_ok = 1;
 689                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
 690                                 SSL3_ST_SR_FINISHED_B);
 691                         if (ret <= 0) goto end;
 692                         dtls1_stop_timer(s);
 693                         if (s->hit)
 694                                 s->state=SSL_ST_OK;
 695 #ifndef OPENSSL_NO_TLSEXT
 696                         else if (s->tlsext_ticket_expected)
 697                                 s->state=SSL3_ST_SW_SESSION_TICKET_A;
 698 #endif
 699                         else
 700                                 s->state=SSL3_ST_SW_CHANGE_A;
 701                         s->init_num=0;
 702                         break;
 703
 704 #ifndef OPENSSL_NO_TLSEXT
 705                 case SSL3_ST_SW_SESSION_TICKET_A:
 706                 case SSL3_ST_SW_SESSION_TICKET_B:
 707                         ret=ssl3_send_newsession_ticket(s);
 708                         if (ret <= 0) goto end;
 709                         s->state=SSL3_ST_SW_CHANGE_A;
 710                         s->init_num=0;
 711                         break;
 712
 713                 case SSL3_ST_SW_CERT_STATUS_A:
 714                 case SSL3_ST_SW_CERT_STATUS_B:
 715                         ret=ssl3_send_cert_status(s);
 716                         if (ret <= 0) goto end;
 717                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 718                         s->init_num=0;
 719                         break;
 720
 721 #endif
 722
 723                 case SSL3_ST_SW_CHANGE_A:
 724                 case SSL3_ST_SW_CHANGE_B:
 725
 726                         s->session->cipher=s->s3->tmp.new_cipher;
 727                         if (!s->method->ssl3_enc->setup_key_block(s))
 728                                 { ret= -1; goto end; }
 729
 730                         ret=dtls1_send_change_cipher_spec(s,
 731                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
 732
 733                         if (ret <= 0) goto end;
 734
 735 #ifndef OPENSSL_NO_SCTP
 736                         /* Change to new shared key of SCTP-Auth,
 737                          * will be ignored if no SCTP used.
 738                          */
 739                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
 740 #endif
 741
 742                         s->state=SSL3_ST_SW_FINISHED_A;
 743                         s->init_num=0;
 744
 745                         if (!s->method->ssl3_enc->change_cipher_state(s,
 746                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
 747                                 {
 748                                 ret= -1;
 749                                 goto end;
 750                                 }
 751
 752                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
 753                         break;
 754
 755                 case SSL3_ST_SW_FINISHED_A:
 756                 case SSL3_ST_SW_FINISHED_B:
 757                         ret=ssl3_send_finished(s,
 758                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
 759                                 s->method->ssl3_enc->server_finished_label,
 760                                 s->method->ssl3_enc->server_finished_label_len);
 761                         if (ret <= 0) goto end;
 762                         s->state=SSL3_ST_SW_FLUSH;
 763                         if (s->hit)
 764                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
 765                         else
 766                                 {
 767                                 s->s3->tmp.next_state=SSL_ST_OK;
 768 #ifndef OPENSSL_NO_SCTP
 769                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 770                                         {
 771                                         s->d1->next_state = s->s3->tmp.next_state;
 772                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 773                                         }
 774 #endif
 775                                 }
 776                         s->init_num=0;
 777                         break;
 778
 779                 case SSL_ST_OK:
 780                         /* clean a few things up */
 781                         ssl3_cleanup_key_block(s);
 782
 783 #if 0
 784                         BUF_MEM_free(s->init_buf);
 785                         s->init_buf=NULL;
 786 #endif
 787
 788                         /* remove buffering on output */
 789                         ssl_free_wbio_buffer(s);
 790
 791                         s->init_num=0;
 792
 793                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
 794                                 {
 795                                 s->renegotiate=0;
 796                                 s->new_session=0;
 797
 798                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
 799
 800                                 s->ctx->stats.sess_accept_good++;
 801                                 /* s->server=1; */
 802                                 s->handshake_func=dtls1_accept;
 803
 804                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
 805                                 }
 806
 807                         ret = 1;
 808
 809                         /* done handshaking, next message is client hello */
 810                         s->d1->handshake_read_seq = 0;
 811                         /* next message is server hello */
 812                         s->d1->handshake_write_seq = 0;
 813                         s->d1->next_handshake_write_seq = 0;
 814                         goto end;
 815                         /* break; */
 816
 817                 default:
 818                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
 819                         ret= -1;
 820                         goto end;
 821                         /* break; */
 822                         }
 823
 824                 if (!s->s3->tmp.reuse_message && !skip)
 825                         {
 826                         if (s->debug)
 827                                 {
 828                                 if ((ret=BIO_flush(s->wbio)) <= 0)
 829                                         goto end;
 830                                 }
 831
 832
 833                         if ((cb != NULL) && (s->state != state))
 834                                 {
 835                                 new_state=s->state;
 836                                 s->state=state;
 837                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
 838                                 s->state=new_state;
 839                                 }
 840                         }
 841                 skip=0;
 842                 }
 843 end:
 844         /* BIO_flush(s->wbio); */
 845
 846         s->in_handshake--;
 847 #ifndef OPENSSL_NO_SCTP
 848                 /* Notify SCTP BIO socket to leave handshake
 849                  * mode and prevent stream identifier other
 850                  * than 0. Will be ignored if no SCTP is used.
 851                  */
 852                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 853 #endif
 854
 855         if (cb != NULL)
 856                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
 857         return(ret);
 858         }
 859
 860 int dtls1_send_hello_verify_request(SSL *s)
 861         {
 862         unsigned int msg_len;
 863         unsigned char *msg, *buf, *p;
 864
 865         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
 866                 {
 867                 buf = (unsigned char *)s->init_buf->data;
 868
 869                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
 870                 *(p++) = s->version >> 8;
 871                 *(p++) = s->version & 0xFF;
 872
 873                 if (s->ctx->app_gen_cookie_cb == NULL ||
 874                      s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
 875                          &(s->d1->cookie_len)) == 0)
 876                         {
 877                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
 878                         return 0;
 879                         }
 880
 881                 *(p++) = (unsigned char) s->d1->cookie_len;
 882                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
 883                 p += s->d1->cookie_len;
 884                 msg_len = p - msg;
 885
 886                 dtls1_set_message_header(s, buf,
 887                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
 888
 889                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
 890                 /* number of bytes to write */
 891                 s->init_num=p-buf;
 892                 s->init_off=0;
 893                 }
 894
 895         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
 896         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
 897         }