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_clear_record_buffer(s);
 298                         dtls1_start_timer(s);
 299                         ret=ssl3_send_hello_request(s);
 300                         if (ret <= 0) goto end;
 301                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
 302                         s->state=SSL3_ST_SW_FLUSH;
 303                         s->init_num=0;
 304
 305                         ssl3_init_finished_mac(s);
 306                         break;
 307
 308                 case SSL3_ST_SW_HELLO_REQ_C:
 309                         s->state=SSL_ST_OK;
 310                         break;
 311
 312                 case SSL3_ST_SR_CLNT_HELLO_A:
 313                 case SSL3_ST_SR_CLNT_HELLO_B:
 314                 case SSL3_ST_SR_CLNT_HELLO_C:
 315
 316                         s->shutdown=0;
 317                         ret=ssl3_get_client_hello(s);
 318                         if (ret <= 0) goto end;
 319                         dtls1_stop_timer(s);
 320
 321                         if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
 322                                 s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
 323                         else
 324                                 s->state = SSL3_ST_SW_SRVR_HELLO_A;
 325
 326                         s->init_num=0;
 327
 328                         /* Reflect ClientHello sequence to remain stateless while listening */
 329                         if (listen)
 330                                 {
 331                                 memcpy(s->s3->write_sequence, s->s3->read_sequence, sizeof(s->s3->write_sequence));
 332                                 }
 333
 334                         /* If we're just listening, stop here */
 335                         if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A)
 336                                 {
 337                                 ret = 2;
 338                                 s->d1->listen = 0;
 339                                 /* Set expected sequence numbers
 340                                  * to continue the handshake.
 341                                  */
 342                                 s->d1->handshake_read_seq = 2;
 343                                 s->d1->handshake_write_seq = 1;
 344                                 s->d1->next_handshake_write_seq = 1;
 345                                 goto end;
 346                                 }
 347
 348                         break;
 349
 350                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
 351                 case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
 352
 353                         ret = dtls1_send_hello_verify_request(s);
 354                         if ( ret <= 0) goto end;
 355                         s->state=SSL3_ST_SW_FLUSH;
 356                         s->s3->tmp.next_state=SSL3_ST_SR_CLNT_HELLO_A;
 357
 358                         /* HelloVerifyRequest resets Finished MAC */
 359                         if (s->version != DTLS1_BAD_VER)
 360                                 ssl3_init_finished_mac(s);
 361                         break;
 362
 363 #ifndef OPENSSL_NO_SCTP
 364                 case DTLS1_SCTP_ST_SR_READ_SOCK:
 365
 366                         if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 367                                 {
 368                                 s->s3->in_read_app_data=2;
 369                                 s->rwstate=SSL_READING;
 370                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 371                                 BIO_set_retry_read(SSL_get_rbio(s));
 372                                 ret = -1;
 373                                 goto end;
 374                                 }
 375
 376                         s->state=SSL3_ST_SR_FINISHED_A;
 377                         break;
 378
 379                 case DTLS1_SCTP_ST_SW_WRITE_SOCK:
 380                         ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
 381                         if (ret < 0) goto end;
 382
 383                         if (ret == 0)
 384                                 {
 385                                 if (s->d1->next_state != SSL_ST_OK)
 386                                         {
 387                                         s->s3->in_read_app_data=2;
 388                                         s->rwstate=SSL_READING;
 389                                         BIO_clear_retry_flags(SSL_get_rbio(s));
 390                                         BIO_set_retry_read(SSL_get_rbio(s));
 391                                         ret = -1;
 392                                         goto end;
 393                                         }
 394                                 }
 395
 396                         s->state=s->d1->next_state;
 397                         break;
 398 #endif
 399
 400                 case SSL3_ST_SW_SRVR_HELLO_A:
 401                 case SSL3_ST_SW_SRVR_HELLO_B:
 402                         s->renegotiate = 2;
 403                         dtls1_start_timer(s);
 404                         ret=ssl3_send_server_hello(s);
 405                         if (ret <= 0) goto end;
 406
 407                         if (s->hit)
 408                                 {
 409 #ifndef OPENSSL_NO_SCTP
 410                                 /* Add new shared key for SCTP-Auth,
 411                                  * will be ignored if no SCTP used.
 412                                  */
 413                                 snprintf((char*) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 414                                          DTLS1_SCTP_AUTH_LABEL);
 415
 416                                 SSL_export_keying_material(s, sctpauthkey,
 417                                                            sizeof(sctpauthkey), labelbuffer,
 418                                                            sizeof(labelbuffer), NULL, 0, 0);
 419
 420                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 421                          sizeof(sctpauthkey), sctpauthkey);
 422 #endif
 423 #ifndef OPENSSL_NO_TLSEXT
 424                                 if (s->tlsext_ticket_expected)
 425                                         s->state=SSL3_ST_SW_SESSION_TICKET_A;
 426                                 else
 427                                         s->state=SSL3_ST_SW_CHANGE_A;
 428 #else
 429                                 s->state=SSL3_ST_SW_CHANGE_A;
 430 #endif
 431                                 }
 432                         else
 433                                 s->state=SSL3_ST_SW_CERT_A;
 434                         s->init_num=0;
 435                         break;
 436
 437                 case SSL3_ST_SW_CERT_A:
 438                 case SSL3_ST_SW_CERT_B:
 439                         /* Check if it is anon DH or normal PSK */
 440                         if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
 441                                 && !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 442                                 {
 443                                 dtls1_start_timer(s);
 444                                 ret=ssl3_send_server_certificate(s);
 445                                 if (ret <= 0) goto end;
 446 #ifndef OPENSSL_NO_TLSEXT
 447                                 if (s->tlsext_status_expected)
 448                                         s->state=SSL3_ST_SW_CERT_STATUS_A;
 449                                 else
 450                                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 451                                 }
 452                         else
 453                                 {
 454                                 skip = 1;
 455                                 s->state=SSL3_ST_SW_KEY_EXCH_A;
 456                                 }
 457 #else
 458                                 }
 459                         else
 460                                 skip=1;
 461
 462                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 463 #endif
 464                         s->init_num=0;
 465                         break;
 466
 467                 case SSL3_ST_SW_KEY_EXCH_A:
 468                 case SSL3_ST_SW_KEY_EXCH_B:
 469                         alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
 470
 471                         /* clear this, it may get reset by
 472                          * send_server_key_exchange */
 473                         if ((s->options & SSL_OP_EPHEMERAL_RSA)
 474 #ifndef OPENSSL_NO_KRB5
 475                                 && !(alg_k & SSL_kKRB5)
 476 #endif /* OPENSSL_NO_KRB5 */
 477                                 )
 478                                 /* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
 479                                  * even when forbidden by protocol specs
 480                                  * (handshake may fail as clients are not required to
 481                                  * be able to handle this) */
 482                                 s->s3->tmp.use_rsa_tmp=1;
 483                         else
 484                                 s->s3->tmp.use_rsa_tmp=0;
 485
 486                         /* only send if a DH key exchange or
 487                          * RSA but we have a sign only certificate */
 488                         if (s->s3->tmp.use_rsa_tmp
 489                         /* PSK: send ServerKeyExchange if PSK identity
 490                          * hint if provided */
 491 #ifndef OPENSSL_NO_PSK
 492                             || ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
 493 #endif
 494                             || (alg_k & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
 495                             || (alg_k & SSL_kEECDH)
 496                             || ((alg_k & SSL_kRSA)
 497                                 && (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
 498                                     || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
 499                                         && EVP_PKEY_size(s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey)*8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
 500                                         )
 501                                     )
 502                                 )
 503                             )
 504                                 {
 505                                 dtls1_start_timer(s);
 506                                 ret=ssl3_send_server_key_exchange(s);
 507                                 if (ret <= 0) goto end;
 508                                 }
 509                         else
 510                                 skip=1;
 511
 512                         s->state=SSL3_ST_SW_CERT_REQ_A;
 513                         s->init_num=0;
 514                         break;
 515
 516                 case SSL3_ST_SW_CERT_REQ_A:
 517                 case SSL3_ST_SW_CERT_REQ_B:
 518                         if (/* don't request cert unless asked for it: */
 519                                 !(s->verify_mode & SSL_VERIFY_PEER) ||
 520                                 /* if SSL_VERIFY_CLIENT_ONCE is set,
 521                                  * don't request cert during re-negotiation: */
 522                                 ((s->session->peer != NULL) &&
 523                                  (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
 524                                 /* never request cert in anonymous ciphersuites
 525                                  * (see section "Certificate request" in SSL 3 drafts
 526                                  * and in RFC 2246): */
 527                                 ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
 528                                  /* ... except when the application insists on verification
 529                                   * (against the specs, but s3_clnt.c accepts this for SSL 3) */
 530                                  !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) ||
 531                                  /* never request cert in Kerberos ciphersuites */
 532                                 (s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
 533                                 /* With normal PSK Certificates and
 534                                  * Certificate Requests are omitted */
 535                                 || (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
 536                                 {
 537                                 /* no cert request */
 538                                 skip=1;
 539                                 s->s3->tmp.cert_request=0;
 540                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 541 #ifndef OPENSSL_NO_SCTP
 542                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 543                                         {
 544                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 545                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 546                                         }
 547 #endif
 548                                 }
 549                         else
 550                                 {
 551                                 s->s3->tmp.cert_request=1;
 552                                 dtls1_start_timer(s);
 553                                 ret=ssl3_send_certificate_request(s);
 554                                 if (ret <= 0) goto end;
 555 #ifndef NETSCAPE_HANG_BUG
 556                                 s->state=SSL3_ST_SW_SRVR_DONE_A;
 557 #ifndef OPENSSL_NO_SCTP
 558                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 559                                         {
 560                                         s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
 561                                         s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
 562                                         }
 563 #endif
 564 #else
 565                                 s->state=SSL3_ST_SW_FLUSH;
 566                                 s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 567 #ifndef OPENSSL_NO_SCTP
 568                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 569                                         {
 570                                         s->d1->next_state = s->s3->tmp.next_state;
 571                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 572                                         }
 573 #endif
 574 #endif
 575                                 s->init_num=0;
 576                                 }
 577                         break;
 578
 579                 case SSL3_ST_SW_SRVR_DONE_A:
 580                 case SSL3_ST_SW_SRVR_DONE_B:
 581                         dtls1_start_timer(s);
 582                         ret=ssl3_send_server_done(s);
 583                         if (ret <= 0) goto end;
 584                         s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
 585                         s->state=SSL3_ST_SW_FLUSH;
 586                         s->init_num=0;
 587                         break;
 588
 589                 case SSL3_ST_SW_FLUSH:
 590                         s->rwstate=SSL_WRITING;
 591                         if (BIO_flush(s->wbio) <= 0)
 592                                 {
 593                                 /* If the write error was fatal, stop trying */
 594                                 if (!BIO_should_retry(s->wbio))
 595                                         {
 596                                         s->rwstate=SSL_NOTHING;
 597                                         s->state=s->s3->tmp.next_state;
 598                                         }
 599
 600                                 ret= -1;
 601                                 goto end;
 602                                 }
 603                         s->rwstate=SSL_NOTHING;
 604                         s->state=s->s3->tmp.next_state;
 605                         break;
 606
 607                 case SSL3_ST_SR_CERT_A:
 608                 case SSL3_ST_SR_CERT_B:
 609                         /* Check for second client hello (MS SGC) */
 610                         ret = ssl3_check_client_hello(s);
 611                         if (ret <= 0)
 612                                 goto end;
 613                         if (ret == 2)
 614                                 {
 615                                 dtls1_stop_timer(s);
 616                                 s->state = SSL3_ST_SR_CLNT_HELLO_C;
 617                                 }
 618                         else {
 619                                 /* could be sent for a DH cert, even if we
 620                                  * have not asked for it :-) */
 621                                 ret=ssl3_get_client_certificate(s);
 622                                 if (ret <= 0) goto end;
 623                                 s->init_num=0;
 624                                 s->state=SSL3_ST_SR_KEY_EXCH_A;
 625                         }
 626                         break;
 627
 628                 case SSL3_ST_SR_KEY_EXCH_A:
 629                 case SSL3_ST_SR_KEY_EXCH_B:
 630                         ret=ssl3_get_client_key_exchange(s);
 631                         if (ret <= 0) goto end;
 632 #ifndef OPENSSL_NO_SCTP
 633                         /* Add new shared key for SCTP-Auth,
 634                          * will be ignored if no SCTP used.
 635                          */
 636                         snprintf((char *) labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
 637                                  DTLS1_SCTP_AUTH_LABEL);
 638
 639                         SSL_export_keying_material(s, sctpauthkey,
 640                                                    sizeof(sctpauthkey), labelbuffer,
 641                                                    sizeof(labelbuffer), NULL, 0, 0);
 642
 643                         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
 644                                  sizeof(sctpauthkey), sctpauthkey);
 645 #endif
 646
 647                         s->state=SSL3_ST_SR_CERT_VRFY_A;
 648                         s->init_num=0;
 649
 650                         if (ret == 2)
 651                                 {
 652                                 /* For the ECDH ciphersuites when
 653                                  * the client sends its ECDH pub key in
 654                                  * a certificate, the CertificateVerify
 655                                  * message is not sent.
 656                                  */
 657                                 s->state=SSL3_ST_SR_FINISHED_A;
 658                                 s->init_num = 0;
 659                                 }
 660                         else if (SSL_USE_SIGALGS(s))
 661                                 {
 662                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
 663                                 s->init_num=0;
 664                                 if (!s->session->peer)
 665                                         break;
 666                                 /* For sigalgs freeze the handshake buffer
 667                                  * at this point and digest cached records.
 668                                  */
 669                                 if (!s->s3->handshake_buffer)
 670                                         {
 671                                         SSLerr(SSL_F_DTLS1_ACCEPT,ERR_R_INTERNAL_ERROR);
 672                                         return -1;
 673                                         }
 674                                 s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
 675                                 if (!ssl3_digest_cached_records(s))
 676                                         return -1;
 677                                 }
 678                         else
 679                                 {
 680                                 s->state=SSL3_ST_SR_CERT_VRFY_A;
 681                                 s->init_num=0;
 682
 683                                 /* We need to get hashes here so if there is
 684                                  * a client cert, it can be verified */
 685                                 s->method->ssl3_enc->cert_verify_mac(s,
 686                                         NID_md5,
 687                                         &(s->s3->tmp.cert_verify_md[0]));
 688                                 s->method->ssl3_enc->cert_verify_mac(s,
 689                                         NID_sha1,
 690                                         &(s->s3->tmp.cert_verify_md[MD5_DIGEST_LENGTH]));
 691                                 }
 692                         break;
 693
 694                 case SSL3_ST_SR_CERT_VRFY_A:
 695                 case SSL3_ST_SR_CERT_VRFY_B:
 696
 697                         s->d1->change_cipher_spec_ok = 1;
 698                         /* we should decide if we expected this one */
 699                         ret=ssl3_get_cert_verify(s);
 700                         if (ret <= 0) goto end;
 701 #ifndef OPENSSL_NO_SCTP
 702                         if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
 703                             state == SSL_ST_RENEGOTIATE)
 704                                 s->state=DTLS1_SCTP_ST_SR_READ_SOCK;
 705                         else
 706 #endif
 707                                 s->state=SSL3_ST_SR_FINISHED_A;
 708                         s->init_num=0;
 709                         break;
 710
 711                 case SSL3_ST_SR_FINISHED_A:
 712                 case SSL3_ST_SR_FINISHED_B:
 713                         s->d1->change_cipher_spec_ok = 1;
 714                         ret=ssl3_get_finished(s,SSL3_ST_SR_FINISHED_A,
 715                                 SSL3_ST_SR_FINISHED_B);
 716                         if (ret <= 0) goto end;
 717                         dtls1_stop_timer(s);
 718                         if (s->hit)
 719                                 s->state=SSL_ST_OK;
 720 #ifndef OPENSSL_NO_TLSEXT
 721                         else if (s->tlsext_ticket_expected)
 722                                 s->state=SSL3_ST_SW_SESSION_TICKET_A;
 723 #endif
 724                         else
 725                                 s->state=SSL3_ST_SW_CHANGE_A;
 726                         s->init_num=0;
 727                         break;
 728
 729 #ifndef OPENSSL_NO_TLSEXT
 730                 case SSL3_ST_SW_SESSION_TICKET_A:
 731                 case SSL3_ST_SW_SESSION_TICKET_B:
 732                         ret=ssl3_send_newsession_ticket(s);
 733                         if (ret <= 0) goto end;
 734                         s->state=SSL3_ST_SW_CHANGE_A;
 735                         s->init_num=0;
 736                         break;
 737
 738                 case SSL3_ST_SW_CERT_STATUS_A:
 739                 case SSL3_ST_SW_CERT_STATUS_B:
 740                         ret=ssl3_send_cert_status(s);
 741                         if (ret <= 0) goto end;
 742                         s->state=SSL3_ST_SW_KEY_EXCH_A;
 743                         s->init_num=0;
 744                         break;
 745
 746 #endif
 747
 748                 case SSL3_ST_SW_CHANGE_A:
 749                 case SSL3_ST_SW_CHANGE_B:
 750
 751                         s->session->cipher=s->s3->tmp.new_cipher;
 752                         if (!s->method->ssl3_enc->setup_key_block(s))
 753                                 { ret= -1; goto end; }
 754
 755                         ret=dtls1_send_change_cipher_spec(s,
 756                                 SSL3_ST_SW_CHANGE_A,SSL3_ST_SW_CHANGE_B);
 757
 758                         if (ret <= 0) goto end;
 759
 760 #ifndef OPENSSL_NO_SCTP
 761                         if (!s->hit)
 762                                 {
 763                                 /* Change to new shared key of SCTP-Auth,
 764                                  * will be ignored if no SCTP used.
 765                                  */
 766                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
 767                                 }
 768 #endif
 769
 770                         s->state=SSL3_ST_SW_FINISHED_A;
 771                         s->init_num=0;
 772
 773                         if (!s->method->ssl3_enc->change_cipher_state(s,
 774                                 SSL3_CHANGE_CIPHER_SERVER_WRITE))
 775                                 {
 776                                 ret= -1;
 777                                 goto end;
 778                                 }
 779
 780                         dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
 781                         break;
 782
 783                 case SSL3_ST_SW_FINISHED_A:
 784                 case SSL3_ST_SW_FINISHED_B:
 785                         ret=ssl3_send_finished(s,
 786                                 SSL3_ST_SW_FINISHED_A,SSL3_ST_SW_FINISHED_B,
 787                                 s->method->ssl3_enc->server_finished_label,
 788                                 s->method->ssl3_enc->server_finished_label_len);
 789                         if (ret <= 0) goto end;
 790                         s->state=SSL3_ST_SW_FLUSH;
 791                         if (s->hit)
 792                                 {
 793                                 s->s3->tmp.next_state=SSL3_ST_SR_FINISHED_A;
 794
 795 #ifndef OPENSSL_NO_SCTP
 796                                 /* Change to new shared key of SCTP-Auth,
 797                                  * will be ignored if no SCTP used.
 798                                  */
 799                                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY, 0, NULL);
 800 #endif
 801                                 }
 802                         else
 803                                 {
 804                                 s->s3->tmp.next_state=SSL_ST_OK;
 805 #ifndef OPENSSL_NO_SCTP
 806                                 if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
 807                                         {
 808                                         s->d1->next_state = s->s3->tmp.next_state;
 809                                         s->s3->tmp.next_state=DTLS1_SCTP_ST_SW_WRITE_SOCK;
 810                                         }
 811 #endif
 812                                 }
 813                         s->init_num=0;
 814                         break;
 815
 816                 case SSL_ST_OK:
 817                         /* clean a few things up */
 818                         ssl3_cleanup_key_block(s);
 819
 820 #if 0
 821                         BUF_MEM_free(s->init_buf);
 822                         s->init_buf=NULL;
 823 #endif
 824
 825                         /* remove buffering on output */
 826                         ssl_free_wbio_buffer(s);
 827
 828                         s->init_num=0;
 829
 830                         if (s->renegotiate == 2) /* skipped if we just sent a HelloRequest */
 831                                 {
 832                                 s->renegotiate=0;
 833                                 s->new_session=0;
 834
 835                                 ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
 836
 837                                 s->ctx->stats.sess_accept_good++;
 838                                 /* s->server=1; */
 839                                 s->handshake_func=dtls1_accept;
 840
 841                                 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
 842                                 }
 843
 844                         ret = 1;
 845
 846                         /* done handshaking, next message is client hello */
 847                         s->d1->handshake_read_seq = 0;
 848                         /* next message is server hello */
 849                         s->d1->handshake_write_seq = 0;
 850                         s->d1->next_handshake_write_seq = 0;
 851                         goto end;
 852                         /* break; */
 853
 854                 default:
 855                         SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
 856                         ret= -1;
 857                         goto end;
 858                         /* break; */
 859                         }
 860
 861                 if (!s->s3->tmp.reuse_message && !skip)
 862                         {
 863                         if (s->debug)
 864                                 {
 865                                 if ((ret=BIO_flush(s->wbio)) <= 0)
 866                                         goto end;
 867                                 }
 868
 869
 870                         if ((cb != NULL) && (s->state != state))
 871                                 {
 872                                 new_state=s->state;
 873                                 s->state=state;
 874                                 cb(s,SSL_CB_ACCEPT_LOOP,1);
 875                                 s->state=new_state;
 876                                 }
 877                         }
 878                 skip=0;
 879                 }
 880 end:
 881         /* BIO_flush(s->wbio); */
 882
 883         s->in_handshake--;
 884 #ifndef OPENSSL_NO_SCTP
 885                 /* Notify SCTP BIO socket to leave handshake
 886                  * mode and prevent stream identifier other
 887                  * than 0. Will be ignored if no SCTP is used.
 888                  */
 889                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE, s->in_handshake, NULL);
 890 #endif
 891
 892         if (cb != NULL)
 893                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
 894         return(ret);
 895         }
 896
 897 int dtls1_send_hello_verify_request(SSL *s)
 898         {
 899         unsigned int msg_len;
 900         unsigned char *msg, *buf, *p;
 901
 902         if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A)
 903                 {
 904                 buf = (unsigned char *)s->init_buf->data;
 905
 906                 msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
 907                 /* Always use DTLS 1.0 version: see RFC 6347 */
 908                 *(p++) = DTLS1_VERSION >> 8;
 909                 *(p++) = DTLS1_VERSION & 0xFF;
 910
 911                 if (s->ctx->app_gen_cookie_cb == NULL ||
 912                      s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
 913                          &(s->d1->cookie_len)) == 0)
 914                         {
 915                         SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,ERR_R_INTERNAL_ERROR);
 916                         return 0;
 917                         }
 918
 919                 *(p++) = (unsigned char) s->d1->cookie_len;
 920                 memcpy(p, s->d1->cookie, s->d1->cookie_len);
 921                 p += s->d1->cookie_len;
 922                 msg_len = p - msg;
 923
 924                 dtls1_set_message_header(s, buf,
 925                         DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0, msg_len);
 926
 927                 s->state=DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
 928                 /* number of bytes to write */
 929                 s->init_num=p-buf;
 930                 s->init_off=0;
 931                 }
 932
 933         /* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
 934         return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
 935         }