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 IMPLEMENT_dtls1_meth_func(DTLS_ANY_VERSION,
 157                         DTLS_server_method,
 158                         dtls1_accept,
 159                         ssl_undefined_function,
 160                         dtls1_get_server_method,
 161                         DTLSv1_2_enc_data)
 162
 163 int dtls1_accept(SSL *s)
 164         {
 165         BUF_MEM *buf;
 166         unsigned long Time=(unsigned long)time(NULL);
 167         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 168         unsigned long alg_k;
 169         int ret= -1;
 170         int new_state,state,skip=0;
 171         int listen;
 172 #ifndef OPENSSL_NO_SCTP
 173         unsigned char sctpauthkey[64];
 174         char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
 175 #endif
 176
 177         RAND_add(&Time,sizeof(Time),0);
 178         ERR_clear_error();
 179         clear_sys_error();
 180
 181         if (s->info_callback != NULL)
 182                 cb=s->info_callback;
 183         else if (s->ctx->info_callback != NULL)
 184                 cb=s->ctx->info_callback;
 185
 186         listen = s->d1->listen;
 187
 188         /* init things to blank */
 189         s->in_handshake++;
 190         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 191
 192         s->d1->listen = listen;
 193 #ifndef OPENSSL_NO_SCTP
 194         /* Notify SCTP BIO socket to enter handshake
 195          * mode and prevent stream identifier other
 196          * than 0. Will be ignored if no SCTP is used.
 197          */
 198         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 199 #endif
 200
 201         if (s->cert == NULL)
 202                 {
 203                 SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
 204                 return(-1);
 205                 }
 206
 207 #ifndef OPENSSL_NO_HEARTBEATS
 208         /* If we're awaiting a HeartbeatResponse, pretend we
 209          * already got and don't await it anymore, because
 210          * Heartbeats don't make sense during handshakes anyway.
 211          */
 212         if (s->tlsext_hb_pending)
 213                 {
 214                 dtls1_stop_timer(s);
 215                 s->tlsext_hb_pending = 0;
 216                 s->tlsext_hb_seq++;
 217                 }
 218 #endif
 219
 220         for (;;)
 221                 {
 222                 state=s->state;
 223
 224                 switch (s->state)
 225                         {
 226                 case SSL_ST_RENEGOTIATE:
 227                         s->renegotiate=1;
 228                         /* s->state=SSL_ST_ACCEPT; */
 229
 230                 case SSL_ST_BEFORE:
 231                 case SSL_ST_ACCEPT:
 232                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
 233                 case SSL_ST_OK|SSL_ST_ACCEPT:
 234
 235                         s->server=1;
 236                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 237
 238                         if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00))
 239                                 {
 240                                 SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
 241                                 return -1;
 242                                 }
 243                         s->type=SSL_ST_ACCEPT;
 244
 245                         if (s->init_buf == NULL)
 246                                 {
 247                                 if ((buf=BUF_MEM_new()) == NULL)
 248                                         {
 249                                         ret= -1;
 250                                         goto end;
 251                                         }
 252                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 253                                         {
 254                                         ret= -1;
 255                                         goto end;
 256                                         }
 257                                 s->init_buf=buf;
 258                                 }
 259
 260                         if (!ssl3_setup_buffers(s))
 261                                 {
 262                                 ret= -1;
 263                                 goto end;
 264                                 }
 265
 266                         s->init_num=0;
 267
 268                         if (s->state != SSL_ST_RENEGOTIATE)
 269                                 {
 270                                 /* Ok, we now need to push on a buffering BIO so that
 271                                  * the output is sent in a way that TCP likes :-)
 272                                  * ...but not with SCTP :-)
 273                                  */
 274 #ifndef OPENSSL_NO_SCTP
 275                                 if (!BIO_dgram_is_sctp(SSL_get_wbio(s)))
 276 #endif
 277                                         if (!ssl_init_wbio_buffer(s,1)) { ret= -1; goto end; }
 278
 279                                 ssl3_init_finished_mac(s);
 280                                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
 281                                 s->ctx->stats.sess_accept++;
 282                                 }
 283                         else
 284                                 {
 285                                 /* s->state == SSL_ST_RENEGOTIATE,
 286                                  * we will just send a HelloRequest */
 287                                 s->ctx->stats.sess_accept_renegotiate++;
 288                                 s->state=SSL3_ST_SW_HELLO_REQ_A;
 289                                 }
 290
 291                         break;
 292
 293                 case SSL3_ST_SW_HELLO_REQ_A:
 294                 case SSL3_ST_SW_HELLO_REQ_B:
 295
 296                         s->shutdown=0;
 297                         dtls1_start_timer(s);
 298                         ret=ssl3_send_hello_request(s);
 299                         if (ret <= 0) goto end;
 300                         s->s3->tmp.next_state=SSL3_ST_SW_HELLO_REQ_C;
 301                         s->state=SSL3_ST_SW_FLUSH;
 302                         s->init_num=0;
 303
 304                         ssl3_init_finished_mac(s);
 305                         break;
 306
 307                 case SSL3_ST_SW_HELLO_REQ_C:
 308                         s->state=SSL_ST_OK;
 309                         break;
 310
 311                 case SSL3_ST_SR_CLNT_HELLO_A:
 312                 case SSL3_ST_SR_CLNT_HELLO_B:
 313                 case SSL3_ST_SR_CLNT_HELLO_C:
 314
 315                         s->shutdown=0;
 316                         ret=ssl3_get_client_hello(s);
 317                         if (ret <= 0) goto end;
 318                         dtls1_stop_timer(s);
 319
 320                         if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
 321                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
 322                         else
 323                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
 324
 325                         s->init_num=0;
 326
 327                         /* Reflect ClientHello sequence to remain stateless while listening */
 328                         if (listen)
 329                                 {
 330                                 memcpy(s->s3->write_sequence, s->s3->read_sequence, sizeof(s->s3->write_sequence));
 331                                 }
 332
 333                         /* If we're just listening, stop here */
 334                         if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A)
 335                                 {
 336                                 ret = 2;
 337                                 s->d1->listen = 0;
 338                                 /* Set expected sequence numbers
 339                                  * to continue the handshake.
 340                                  */
 341                                 s->d1->handshake_read_seq = 2;
 342                                 s->d1->handshake_write_seq = 1;
 343                                 s->d1->next_handshake_write_seq = 1;
 344                                 goto end;
 345                                 }
 346
 347                         break;
 348
 349                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
 350                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
 351
 352                         ret = dtls1_send_hello_verify_request(s);
 353                         if ( ret <= 0) goto end;
 354                         s->state=SSL3_ST_SW_FLUSH;
 355                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
 356
 357                         /* HelloVerifyRequest resets Finished MAC */
 358                         if (s->version != DTLS1_BAD_VER)
 359                                 ssl3_init_finished_mac(s);
 360                         break;
 361
 362 #ifndef OPENSSL_NO_SCTP
 363                 case DTLS1_SCTP_ST_SR_READ_SOCK:
 364
 365                         if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 366                                 {
 367                                 s->s3->in_read_app_data=2;
 368                                 s->rwstate=SSL_READING;
 369                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 370                                 BIO_set_retry_read(SSL_get_rbio(s));
 371                                 ret = -1;
 372                                 goto end;
 373                                 }
 374
 375                         s->state=SSL3_ST_SR_FINISHED_A;
 376                         break;
 377
 378                 case DTLS1_SCTP_ST_SW_WRITE_SOCK:
 379                         ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
 380                         if (ret < 0) goto end;
 381
 382                         if (ret == 0)
 383                                 {
 384                                 if (s->d1->next_state != SSL_ST_OK)
 385                                         {
 386                                         s->s3->in_read_app_data=2;
 387                                         s->rwstate=SSL_READING;
 388                                         BIO_clear_retry_flags(SSL_get_rbio(s));
 389                                         BIO_set_retry_read(SSL_get_rbio(s));
 390                                         ret = -1;
 391                                         goto end;
 392                                         }
 393                                 }
 394
 395                         s->state=s->d1->next_state;
 396                         break;
 397 #endif
 398
 399                 case SSL3_ST_SW_SRVR_HELLO_A:
 400                 case SSL3_ST_SW_SRVR_HELLO_B:
 401                         s->renegotiate = 2;
 402                         dtls1_start_timer(s);
 403                         ret=ssl3_send_server_hello(s);
 404                         if (ret <= 0) goto end;
 405
 406                         if (s->hit)
 407                                 {
 408 #ifndef OPENSSL_NO_SCTP
 409                                 /* Add new shared key for SCTP-Auth,
 410                                  * will be ignored if no SCTP used.
 411                                  */
 412                                 snprintf((char*) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 413                                          DTLS1_SCTP_AUTH_LABEL);
 414
 415                                 SSL_export_keying_material(s, sctpauthkey,
 416                                                            sizeof(sctpauthkey), labelbuffer,
 417                                                            sizeof(labelbuffer), NULL, 0, 0);
 418
 419                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 420                          sizeof(sctpauthkey), sctpauthkey);
 421 #endif
 422 #ifndef OPENSSL_NO_TLSEXT
 423                                 if (s->tlsext_ticket_expected)
 424                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
 425                                 else
 426                                         s->state=SSL3_ST_SW_CHANGE_A;
 427 #else
 428                                 s->state=SSL3_ST_SW_CHANGE_A;
 429 #endif
 430                                 }
 431                         else
 432                                 s->state=SSL3_ST_SW_CERT_A;
 433                         s->init_num=0;
 434                         break;
 435
 436                 case SSL3_ST_SW_CERT_A:
 437                 case SSL3_ST_SW_CERT_B:
 438                         /* Check if it is anon DH or normal PSK */
 439                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
 440                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 441                                 {
 442                                 dtls1_start_timer(s);
 443                                 ret=ssl3_send_server_certificate(s);
 444                                 if (ret <= 0) goto end;
 445 #ifndef OPENSSL_NO_TLSEXT
 446                                 if (s->tlsext_status_expected)
 447                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
 448                                 else
 449                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 450                                 }
 451                         else
 452                                 {
 453                                 skip = 1;
 454                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
 455                                 }
 456 #else
 457                                 }
 458                         else
 459                                 skip=1;
 460
 461                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 462 #endif
 463                         s->init_num=0;
 464                         break;
 465
 466                 case SSL3_ST_SW_KEY_EXCH_A:
 467                 case SSL3_ST_SW_KEY_EXCH_B:
 468                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
 469
 470                         /* clear this, it may get reset by
 471                          * send_server_key_exchange */
 472                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
 473 #ifndef OPENSSL_NO_KRB5
 474                                 && !(alg_k & SSL_kKRB5)
 475 #endif /* OPENSSL_NO_KRB5 */
 476                                 )
 477                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
 478                                  * even when forbidden by protocol specs
 479                                  * (handshake may fail as clients are not required to
 480                                  * be able to handle this) */
 481                                 s->s3->tmp.use_rsa_tmp=1;
 482                         else
 483                                 s->s3->tmp.use_rsa_tmp=0;
 484
 485                         /* only send if a DH key exchange or
 486                          * RSA but we have a sign only certificate */
 487                         if (s->s3->tmp.use_rsa_tmp
 488                         /* PSK: send ServerKeyExchange if PSK identity
 489                          * hint if provided */
 490 #ifndef OPENSSL_NO_PSK
 491                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
 492 #endif
 493                             || (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
 494                             || (alg_k & SSL_kEECDH)
 495                             || ((alg_k & SSL_kRSA)
 496                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
 497                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
 498                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
 499                                         )
 500                                     )
 501                                 )
 502                             )
 503                                 {
 504                                 dtls1_start_timer(s);
 505                                 ret=ssl3_send_server_key_exchange(s);
 506                                 if (ret <= 0) goto end;
 507                                 }
 508                         else
 509                                 skip=1;
 510
 511                         s->state=SSL3_ST_SW_CERT_REQ_A;
 512                         s->init_num=0;
 513                         break;
 514
 515                 case SSL3_ST_SW_CERT_REQ_A:
 516                 case SSL3_ST_SW_CERT_REQ_B:
 517                         if (/* don't request cert unless asked for it: */
 518                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
 519                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
 520                                  * don't request cert during re-negotiation: */
 521                                 ((s->session->peer != NULL) &&
 522                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
 523                                 /* never request cert in anonymous ciphersuites
 524                                  * (see section "Certificate request" in SSL 3 drafts
 525                                  * and in RFC 2246): */
 526                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
 527                                  /* ... except when the application insists on verification
 528                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
 529                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
 530                                  /* never request cert in Kerberos ciphersuites */
 531                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
 532                                 /* With normal PSK Certificates and
 533                                  * Certificate Requests are omitted */
 534                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 535                                 {
 536                                 /* no cert request */
 537                                 skip=1;
 538                                 s->s3->tmp.cert_request=0;
 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                                 }
 548                         else
 549                                 {
 550                                 s->s3->tmp.cert_request=1;
 551                                 dtls1_start_timer(s);
 552                                 ret=ssl3_send_certificate_request(s);
 553                                 if (ret <= 0) goto end;
 554 #ifndef NETSCAPE_HANG_BUG
 555                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 556 #ifndef OPENSSL_NO_SCTP
 557                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 558                                         {
 559                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 560                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 561                                         }
 562 #endif
 563 #else
 564                                 s->state=SSL3_ST_SW_FLUSH;
 565                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 566 #ifndef OPENSSL_NO_SCTP
 567                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 568                                         {
 569                                         s->d1->next_state = s->s3->tmp.next_state;
 570                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 571                                         }
 572 #endif
 573 #endif
 574                                 s->init_num=0;
 575                                 }
 576                         break;
 577
 578                 case SSL3_ST_SW_SRVR_DONE_A:
 579                 case SSL3_ST_SW_SRVR_DONE_B:
 580                         dtls1_start_timer(s);
 581                         ret=ssl3_send_server_done(s);
 582                         if (ret <= 0) goto end;
 583                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 584                         s->state=SSL3_ST_SW_FLUSH;
 585                         s->init_num=0;
 586                         break;
 587
 588                 case SSL3_ST_SW_FLUSH:
 589                         s->rwstate=SSL_WRITING;
 590                         if (BIO_flush(s->wbio) <= 0)
 591                                 {
 592                                 /* If the write error was fatal, stop trying */
 593                                 if (!BIO_should_retry(s->wbio))
 594                                         {
 595                                         s->rwstate=SSL_NOTHING;
 596                                         s->state=s->s3->tmp.next_state;
 597                                         }
 598
 599                                 ret= -1;
 600                                 goto end;
 601                                 }
 602                         s->rwstate=SSL_NOTHING;
 603                         s->state=s->s3->tmp.next_state;
 604                         break;
 605
 606                 case SSL3_ST_SR_CERT_A:
 607                 case SSL3_ST_SR_CERT_B:
 608                         /* Check for second client hello (MS SGC) */
 609                         ret = ssl3_check_client_hello(s);
 610                         if (ret <= 0)
 611                                 goto end;
 612                         if (ret == 2)
 613                                 {
 614                                 dtls1_stop_timer(s);
 615                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
 616                                 }
 617                         else {
 618                                 /* could be sent for a DH cert, even if we
 619                                  * have not asked for it :-) */
 620                                 ret=ssl3_get_client_certificate(s);
 621                                 if (ret <= 0) goto end;
 622                                 s->init_num=0;
 623                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
 624                         }
 625                         break;
 626
 627                 case SSL3_ST_SR_KEY_EXCH_A:
 628                 case SSL3_ST_SR_KEY_EXCH_B:
 629                         ret=ssl3_get_client_key_exchange(s);
 630                         if (ret <= 0) goto end;
 631 #ifndef OPENSSL_NO_SCTP
 632                         /* Add new shared key for SCTP-Auth,
 633                          * will be ignored if no SCTP used.
 634                          */
 635                         snprintf((char *) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 636                                  DTLS1_SCTP_AUTH_LABEL);
 637
 638                         SSL_export_keying_material(s, sctpauthkey,
 639                                                    sizeof(sctpauthkey), labelbuffer,
 640                                                    sizeof(labelbuffer), NULL, 0, 0);
 641
 642                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 643                                  sizeof(sctpauthkey), sctpauthkey);
 644 #endif
 645
 646                         s->state=SSL3_ST_SR_CERT_VRFY_A;
 647                         s->init_num=0;
 648
 649                         if (ret == 2)
 650                                 {
 651                                 /* For the ECDH ciphersuites when
 652                                  * the client sends its ECDH pub key in
 653                                  * a certificate, the CertificateVerify
 654                                  * message is not sent.
 655                                  */
 656                                 s->state=SSL3_ST_SR_FINISHED_A;
 657                                 s->init_num = 0;
 658                                 }
 659                         else if (SSL_USE_SIGALGS(s))
 660                                 {
 661                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
 662                                 s->init_num=0;
 663                                 if (!s->session->peer)
 664                                         break;
 665                                 /* For sigalgs freeze the handshake buffer
 666                                  * at this point and digest cached records.
 667                                  */
 668                                 if (!s->s3->handshake_buffer)
 669                                         {
 670                                         SSLerr(SSL_F_DTLS1_ACCEPT,ERR_R_INTERNAL_ERROR);
 671                                         return -1;
 672                                         }
 673                                 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
 674                                 if (!ssl3_digest_cached_records(s))
 675                                         return -1;
 676                                 }
 677                         else
 678                                 {
 679                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
 680                                 s->init_num=0;
 681
 682                                 /* We need to get hashes here so if there is
 683                                  * a client cert, it can be verified */
 684                                 s->method->ssl3_enc->cert_verify_mac(s,
 685                                         NID_md5,
 686                                         &(s->s3->tmp.cert_verify_md[0]));
 687                                 s->method->ssl3_enc->cert_verify_mac(s,
 688                                         NID_sha1,
 689                                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
 690                                 }
 691                         break;
 692
 693                 case SSL3_ST_SR_CERT_VRFY_A:
 694                 case SSL3_ST_SR_CERT_VRFY_B:
 695
 696                         s->d1->change_cipher_spec_ok = 1;
 697                         /* we should decide if we expected this one */
 698                         ret=ssl3_get_cert_verify(s);
 699                         if (ret <= 0) goto end;
 700 #ifndef OPENSSL_NO_SCTP
 701                         if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
 702                             state == SSL_ST_RENEGOTIATE)
 703                                 s->state=DTLS1_SCTP_ST_SR_READ_SOCK;
 704                         else
 705 #endif
 706                                 s->state=SSL3_ST_SR_FINISHED_A;
 707                         s->init_num=0;
 708                         break;
 709
 710                 case SSL3_ST_SR_FINISHED_A:
 711                 case SSL3_ST_SR_FINISHED_B:
 712                         s->d1->change_cipher_spec_ok = 1;
 713                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
 714                                 SSL3_ST_SR_FINISHED_B);
 715                         if (ret <= 0) goto end;
 716                         dtls1_stop_timer(s);
 717                         if (s->hit)
 718                                 s->state=SSL_ST_OK;
 719 #ifndef OPENSSL_NO_TLSEXT
 720                         else if (s->tlsext_ticket_expected)
 721                                 s->state=SSL3_ST_SW_SESSION_TICKET_A;
 722 #endif
 723                         else
 724                                 s->state=SSL3_ST_SW_CHANGE_A;
 725                         s->init_num=0;
 726                         break;
 727
 728 #ifndef OPENSSL_NO_TLSEXT
 729                 case SSL3_ST_SW_SESSION_TICKET_A:
 730                 case SSL3_ST_SW_SESSION_TICKET_B:
 731                         ret=ssl3_send_newsession_ticket(s);
 732                         if (ret <= 0) goto end;
 733                         s->state=SSL3_ST_SW_CHANGE_A;
 734                         s->init_num=0;
 735                         break;
 736
 737                 case SSL3_ST_SW_CERT_STATUS_A:
 738                 case SSL3_ST_SW_CERT_STATUS_B:
 739                         ret=ssl3_send_cert_status(s);
 740                         if (ret <= 0) goto end;
 741                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 742                         s->init_num=0;
 743                         break;
 744
 745 #endif
 746
 747                 case SSL3_ST_SW_CHANGE_A:
 748                 case SSL3_ST_SW_CHANGE_B:
 749
 750                         s->session->cipher=s->s3->tmp.new_cipher;
 751                         if (!s->method->ssl3_enc->setup_key_block(s))
 752                                 { ret= -1; goto end; }
 753
 754                         ret=dtls1_send_change_cipher_spec(s,
 755                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
 756
 757                         if (ret <= 0) goto end;
 758
 759 #ifndef OPENSSL_NO_SCTP
 760                         /* Change to new shared key of SCTP-Auth,
 761                          * will be ignored if no SCTP used.
 762                          */
 763                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
 764 #endif
 765
 766                         s->state=SSL3_ST_SW_FINISHED_A;
 767                         s->init_num=0;
 768
 769                         if (!s->method->ssl3_enc->change_cipher_state(s,
 770                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
 771                                 {
 772                                 ret= -1;
 773                                 goto end;
 774                                 }
 775
 776                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
 777                         break;
 778
 779                 case SSL3_ST_SW_FINISHED_A:
 780                 case SSL3_ST_SW_FINISHED_B:
 781                         ret=ssl3_send_finished(s,
 782                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
 783                                 s->method->ssl3_enc->server_finished_label,
 784                                 s->method->ssl3_enc->server_finished_label_len);
 785                         if (ret <= 0) goto end;
 786                         s->state=SSL3_ST_SW_FLUSH;
 787                         if (s->hit)
 788                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
 789                         else
 790                                 {
 791                                 s->s3->tmp.next_state=SSL_ST_OK;
 792 #ifndef OPENSSL_NO_SCTP
 793                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 794                                         {
 795                                         s->d1->next_state = s->s3->tmp.next_state;
 796                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 797                                         }
 798 #endif
 799                                 }
 800                         s->init_num=0;
 801                         break;
 802
 803                 case SSL_ST_OK:
 804                         /* clean a few things up */
 805                         ssl3_cleanup_key_block(s);
 806
 807 #if 0
 808                         BUF_MEM_free(s->init_buf);
 809                         s->init_buf=NULL;
 810 #endif
 811
 812                         /* remove buffering on output */
 813                         ssl_free_wbio_buffer(s);
 814
 815                         s->init_num=0;
 816
 817                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
 818                                 {
 819                                 s->renegotiate=0;
 820                                 s->new_session=0;
 821
 822                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
 823
 824                                 s->ctx->stats.sess_accept_good++;
 825                                 /* s->server=1; */
 826                                 s->handshake_func=dtls1_accept;
 827
 828                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
 829                                 }
 830
 831                         ret = 1;
 832
 833                         /* done handshaking, next message is client hello */
 834                         s->d1->handshake_read_seq = 0;
 835                         /* next message is server hello */
 836                         s->d1->handshake_write_seq = 0;
 837                         s->d1->next_handshake_write_seq = 0;
 838                         goto end;
 839                         /* break; */
 840
 841                 default:
 842                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
 843                         ret= -1;
 844                         goto end;
 845                         /* break; */
 846                         }
 847
 848                 if (!s->s3->tmp.reuse_message && !skip)
 849                         {
 850                         if (s->debug)
 851                                 {
 852                                 if ((ret=BIO_flush(s->wbio)) <= 0)
 853                                         goto end;
 854                                 }
 855
 856
 857                         if ((cb != NULL) && (s->state != state))
 858                                 {
 859                                 new_state=s->state;
 860                                 s->state=state;
 861                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
 862                                 s->state=new_state;
 863                                 }
 864                         }
 865                 skip=0;
 866                 }
 867 end:
 868         /* BIO_flush(s->wbio); */
 869
 870         s->in_handshake--;
 871 #ifndef OPENSSL_NO_SCTP
 872                 /* Notify SCTP BIO socket to leave handshake
 873                  * mode and prevent stream identifier other
 874                  * than 0. Will be ignored if no SCTP is used.
 875                  */
 876                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 877 #endif
 878
 879         if (cb != NULL)
 880                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
 881         return(ret);
 882         }
 883
 884 int dtls1_send_hello_verify_request(SSL *s)
 885         {
 886         unsigned int msg_len;
 887         unsigned char *msg, *buf, *p;
 888
 889         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
 890                 {
 891                 buf = (unsigned char *)s->init_buf->data;
 892
 893                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
 894                 /* Always use DTLS 1.0 version: see RFC 6347 */
 895                 *(p++) = DTLS1_VERSION >> 8;
 896                 *(p++) = DTLS1_VERSION & 0xFF;
 897
 898                 if (s->ctx->app_gen_cookie_cb == NULL ||
 899                      s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
 900                          &(s->d1->cookie_len)) == 0)
 901                         {
 902                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
 903                         return 0;
 904                         }
 905
 906                 *(p++) = (unsigned char) s->d1->cookie_len;
 907                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
 908                 p += s->d1->cookie_len;
 909                 msg_len = p - msg;
 910
 911                 dtls1_set_message_header(s, buf,
 912                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
 913
 914                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
 915                 /* number of bytes to write */
 916                 s->init_num=p-buf;
 917                 s->init_off=0;
 918                 }
 919
 920         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
 921         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
 922         }