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