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