ssl/s23_clnt.c

   1 /* ssl/s23_clnt.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58 /* ====================================================================
  59  * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
  60  *
  61  * Redistribution and use in source and binary forms, with or without
  62  * modification, are permitted provided that the following conditions
  63  * are met:
  64  *
  65  * 1. Redistributions of source code must retain the above copyright
  66  *    notice, this list of conditions and the following disclaimer.
  67  *
  68  * 2. Redistributions in binary form must reproduce the above copyright
  69  *    notice, this list of conditions and the following disclaimer in
  70  *    the documentation and/or other materials provided with the
  71  *    distribution.
  72  *
  73  * 3. All advertising materials mentioning features or use of this
  74  *    software must display the following acknowledgment:
  75  *    "This product includes software developed by the OpenSSL Project
  76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  77  *
  78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  79  *    endorse or promote products derived from this software without
  80  *    prior written permission. For written permission, please contact
  81  *    openssl-core@openssl.org.
  82  *
  83  * 5. Products derived from this software may not be called "OpenSSL"
  84  *    nor may "OpenSSL" appear in their names without prior written
  85  *    permission of the OpenSSL Project.
  86  *
  87  * 6. Redistributions of any form whatsoever must retain the following
  88  *    acknowledgment:
  89  *    "This product includes software developed by the OpenSSL Project
  90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  91  *
  92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 103  * OF THE POSSIBILITY OF SUCH DAMAGE.
 104  * ====================================================================
 105  *
 106  * This product includes cryptographic software written by Eric Young
 107  * (eay@cryptsoft.com).  This product includes software written by Tim
 108  * Hudson (tjh@cryptsoft.com).
 109  *
 110  */
 111
 112 #include <stdio.h>
 113 #include "ssl_locl.h"
 114 #include <openssl/buffer.h>
 115 #include <openssl/rand.h>
 116 #include <openssl/objects.h>
 117 #include <openssl/evp.h>
 118
 119 static const SSL_METHOD *ssl23_get_client_method(int ver);
 120 static int ssl23_client_hello(SSL *s);
 121 static int ssl23_get_server_hello(SSL *s);
 122 static const SSL_METHOD *ssl23_get_client_method(int ver)
 123         {
 124 #ifndef OPENSSL_NO_SSL2
 125         if (ver == SSL2_VERSION)
 126                 return(SSLv2_client_method());
 127 #endif
 128         if (ver == SSL3_VERSION)
 129                 return(SSLv3_client_method());
 130         else if (ver == TLS1_VERSION)
 131                 return(TLSv1_client_method());
 132         else if (ver == TLS1_1_VERSION)
 133                 return(TLSv1_1_client_method());
 134         else if (ver == TLS1_2_VERSION)
 135                 return(TLSv1_2_client_method());
 136         else
 137                 return(NULL);
 138         }
 139
 140 IMPLEMENT_ssl23_meth_func(SSLv23_client_method,
 141                         ssl_undefined_function,
 142                         ssl23_connect,
 143                         ssl23_get_client_method)
 144
 145 int ssl23_connect(SSL *s)
 146         {
 147         BUF_MEM *buf=NULL;
 148         unsigned long Time=(unsigned long)time(NULL);
 149         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 150         int ret= -1;
 151         int new_state,state;
 152
 153         RAND_add(&Time,sizeof(Time),0);
 154         ERR_clear_error();
 155         clear_sys_error();
 156
 157         if (s->info_callback != NULL)
 158                 cb=s->info_callback;
 159         else if (s->ctx->info_callback != NULL)
 160                 cb=s->ctx->info_callback;
 161
 162         s->in_handshake++;
 163         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 164
 165         for (;;)
 166                 {
 167                 state=s->state;
 168
 169                 switch(s->state)
 170                         {
 171                 case SSL_ST_BEFORE:
 172                 case SSL_ST_CONNECT:
 173                 case SSL_ST_BEFORE|SSL_ST_CONNECT:
 174                 case SSL_ST_OK|SSL_ST_CONNECT:
 175
 176                         if (s->session != NULL)
 177                                 {
 178                                 SSLerr(SSL_F_SSL23_CONNECT,SSL_R_SSL23_DOING_SESSION_ID_REUSE);
 179                                 ret= -1;
 180                                 goto end;
 181                                 }
 182                         s->server=0;
 183                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 184
 185                         /* s->version=TLS1_VERSION; */
 186                         s->type=SSL_ST_CONNECT;
 187
 188                         if (s->init_buf == NULL)
 189                                 {
 190                                 if ((buf=BUF_MEM_new()) == NULL)
 191                                         {
 192                                         ret= -1;
 193                                         goto end;
 194                                         }
 195                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 196                                         {
 197                                         ret= -1;
 198                                         goto end;
 199                                         }
 200                                 s->init_buf=buf;
 201                                 buf=NULL;
 202                                 }
 203
 204                         if (!ssl3_setup_buffers(s)) { ret= -1; goto end; }
 205
 206                         ssl3_init_finished_mac(s);
 207
 208                         s->state=SSL23_ST_CW_CLNT_HELLO_A;
 209                         s->ctx->stats.sess_connect++;
 210                         s->init_num=0;
 211                         break;
 212
 213                 case SSL23_ST_CW_CLNT_HELLO_A:
 214                 case SSL23_ST_CW_CLNT_HELLO_B:
 215
 216                         s->shutdown=0;
 217                         ret=ssl23_client_hello(s);
 218                         if (ret <= 0) goto end;
 219                         s->state=SSL23_ST_CR_SRVR_HELLO_A;
 220                         s->init_num=0;
 221
 222                         break;
 223
 224                 case SSL23_ST_CR_SRVR_HELLO_A:
 225                 case SSL23_ST_CR_SRVR_HELLO_B:
 226                         ret=ssl23_get_server_hello(s);
 227                         if (ret >= 0) cb=NULL;
 228                         goto end;
 229                         /* break; */
 230
 231                 default:
 232                         SSLerr(SSL_F_SSL23_CONNECT,SSL_R_UNKNOWN_STATE);
 233                         ret= -1;
 234                         goto end;
 235                         /* break; */
 236                         }
 237
 238                 if (s->debug) { (void)BIO_flush(s->wbio); }
 239
 240                 if ((cb != NULL) && (s->state != state))
 241                         {
 242                         new_state=s->state;
 243                         s->state=state;
 244                         cb(s,SSL_CB_CONNECT_LOOP,1);
 245                         s->state=new_state;
 246                         }
 247                 }
 248 end:
 249         s->in_handshake--;
 250         if (buf != NULL)
 251                 BUF_MEM_free(buf);
 252         if (cb != NULL)
 253                 cb(s,SSL_CB_CONNECT_EXIT,ret);
 254         return(ret);
 255         }
 256
 257 static int ssl23_no_ssl2_ciphers(SSL *s)
 258         {
 259         SSL_CIPHER *cipher;
 260         STACK_OF(SSL_CIPHER) *ciphers;
 261         int i;
 262         ciphers = SSL_get_ciphers(s);
 263         for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++)
 264                 {
 265                 cipher = sk_SSL_CIPHER_value(ciphers, i);
 266                 if (cipher->algorithm_ssl == SSL_SSLV2)
 267                         return 0;
 268                 }
 269         return 1;
 270         }
 271
 272 static int ssl23_client_hello(SSL *s)
 273         {
 274         unsigned char *buf;
 275         unsigned char *p,*d;
 276         int i,ch_len;
 277         unsigned long Time,l;
 278         int ssl2_compat;
 279         int version = 0, version_major, version_minor;
 280 #ifndef OPENSSL_NO_COMP
 281         int j;
 282         SSL_COMP *comp;
 283 #endif
 284         int ret;
 285
 286         ssl2_compat = (s->options & SSL_OP_NO_SSLv2) ? 0 : 1;
 287
 288         if (ssl2_compat && ssl23_no_ssl2_ciphers(s))
 289                 ssl2_compat = 0;
 290
 291         if (!(s->options & SSL_OP_NO_TLSv1_2))
 292                 {
 293                 version = TLS1_2_VERSION;
 294                 }
 295         else if (!(s->options & SSL_OP_NO_TLSv1_1))
 296                 {
 297                 version = TLS1_1_VERSION;
 298                 }
 299         else if (!(s->options & SSL_OP_NO_TLSv1))
 300                 {
 301                 version = TLS1_VERSION;
 302                 }
 303         else if (!(s->options & SSL_OP_NO_SSLv3))
 304                 {
 305                 version = SSL3_VERSION;
 306                 }
 307         else if (!(s->options & SSL_OP_NO_SSLv2))
 308                 {
 309                 version = SSL2_VERSION;
 310                 }
 311 #ifndef OPENSSL_NO_TLSEXT
 312         if (version != SSL2_VERSION)
 313                 {
 314                 /* have to disable SSL 2.0 compatibility if we need TLS extensions */
 315
 316                 if (s->tlsext_hostname != NULL)
 317                         ssl2_compat = 0;
 318                 if (s->tlsext_status_type != -1)
 319                         ssl2_compat = 0;
 320 #ifdef TLSEXT_TYPE_opaque_prf_input
 321                 if (s->ctx->tlsext_opaque_prf_input_callback != 0 || s->tlsext_opaque_prf_input != NULL)
 322                         ssl2_compat = 0;
 323 #endif
 324                 }
 325 #endif
 326
 327         buf=(unsigned char *)s->init_buf->data;
 328         if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
 329                 {
 330 #if 0
 331                 /* don't reuse session-id's */
 332                 if (!ssl_get_new_session(s,0))
 333                         {
 334                         return(-1);
 335                         }
 336 #endif
 337
 338                 p=s->s3->client_random;
 339                 Time=(unsigned long)time(NULL);         /* Time */
 340                 l2n(Time,p);
 341                 if (RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-4) <= 0)
 342                         return -1;
 343
 344                 if (version == TLS1_2_VERSION)
 345                         {
 346                         version_major = TLS1_2_VERSION_MAJOR;
 347                         version_minor = TLS1_2_VERSION_MINOR;
 348                         }
 349                 else if (version == TLS1_1_VERSION)
 350                         {
 351                         version_major = TLS1_1_VERSION_MAJOR;
 352                         version_minor = TLS1_1_VERSION_MINOR;
 353                         }
 354                 else if (version == TLS1_VERSION)
 355                         {
 356                         version_major = TLS1_VERSION_MAJOR;
 357                         version_minor = TLS1_VERSION_MINOR;
 358                         }
 359 #ifdef OPENSSL_FIPS
 360                 else if(FIPS_mode())
 361                         {
 362                         SSLerr(SSL_F_SSL23_CLIENT_HELLO,
 363                                         SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
 364                         return -1;
 365                         }
 366 #endif
 367                 else if (version == SSL3_VERSION)
 368                         {
 369                         version_major = SSL3_VERSION_MAJOR;
 370                         version_minor = SSL3_VERSION_MINOR;
 371                         }
 372                 else if (version == SSL2_VERSION)
 373                         {
 374                         version_major = SSL2_VERSION_MAJOR;
 375                         version_minor = SSL2_VERSION_MINOR;
 376                         }
 377                 else
 378                         {
 379                         SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_PROTOCOLS_AVAILABLE);
 380                         return(-1);
 381                         }
 382
 383                 s->client_version = version;
 384
 385                 if (ssl2_compat)
 386                         {
 387                         /* create SSL 2.0 compatible Client Hello */
 388
 389                         /* two byte record header will be written last */
 390                         d = &(buf[2]);
 391                         p = d + 9; /* leave space for message type, version, individual length fields */
 392
 393                         *(d++) = SSL2_MT_CLIENT_HELLO;
 394                         *(d++) = version_major;
 395                         *(d++) = version_minor;
 396
 397                         /* Ciphers supported */
 398                         i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),p,0);
 399                         if (i == 0)
 400                                 {
 401                                 /* no ciphers */
 402                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
 403                                 return -1;
 404                                 }
 405                         s2n(i,d);
 406                         p+=i;
 407
 408                         /* put in the session-id length (zero since there is no reuse) */
 409 #if 0
 410                         s->session->session_id_length=0;
 411 #endif
 412                         s2n(0,d);
 413
 414                         if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
 415                                 ch_len=SSL2_CHALLENGE_LENGTH;
 416                         else
 417                                 ch_len=SSL2_MAX_CHALLENGE_LENGTH;
 418
 419                         /* write out sslv2 challenge */
 420                         /* Note that ch_len must be <= SSL3_RANDOM_SIZE (32),
 421                            because it is one of SSL2_MAX_CHALLENGE_LENGTH (32)
 422                            or SSL2_MAX_CHALLENGE_LENGTH (16), but leave the
 423                            check in for futurproofing */
 424                         if (SSL3_RANDOM_SIZE < ch_len)
 425                                 i=SSL3_RANDOM_SIZE;
 426                         else
 427                                 i=ch_len;
 428                         s2n(i,d);
 429                         memset(&(s->s3->client_random[0]),0,SSL3_RANDOM_SIZE);
 430                         if (RAND_pseudo_bytes(&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i) <= 0)
 431                                 return -1;
 432
 433                         memcpy(p,&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
 434                         p+=i;
 435
 436                         i= p- &(buf[2]);
 437                         buf[0]=((i>>8)&0xff)|0x80;
 438                         buf[1]=(i&0xff);
 439
 440                         /* number of bytes to write */
 441                         s->init_num=i+2;
 442                         s->init_off=0;
 443
 444                         ssl3_finish_mac(s,&(buf[2]),i);
 445                         }
 446                 else
 447                         {
 448                         /* create Client Hello in SSL 3.0/TLS 1.0 format */
 449
 450                         /* do the record header (5 bytes) and handshake message header (4 bytes) last */
 451                         d = p = &(buf[9]);
 452
 453                         *(p++) = version_major;
 454                         *(p++) = version_minor;
 455
 456                         /* Random stuff */
 457                         memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
 458                         p += SSL3_RANDOM_SIZE;
 459
 460                         /* Session ID (zero since there is no reuse) */
 461                         *(p++) = 0;
 462
 463                         /* Ciphers supported (using SSL 3.0/TLS 1.0 format) */
 464                         i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),&(p[2]),ssl3_put_cipher_by_char);
 465                         if (i == 0)
 466                                 {
 467                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
 468                                 return -1;
 469                                 }
 470 #ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH
 471                         /* Some servers hang if client hello > 256 bytes
 472                          * as hack workaround chop number of supported ciphers
 473                          * to keep it well below this if we use TLS v1.2
 474                          */
 475                         if (TLS1_get_version(s) >= TLS1_2_VERSION
 476                                 && i > OPENSSL_MAX_TLS1_2_CIPHER_LENGTH)
 477                                 i = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1;
 478 #endif
 479                         s2n(i,p);
 480                         p+=i;
 481
 482                         /* COMPRESSION */
 483 #ifdef OPENSSL_NO_COMP
 484                         *(p++)=1;
 485 #else
 486                         if ((s->options & SSL_OP_NO_COMPRESSION)
 487                                                 || !s->ctx->comp_methods)
 488                                 j=0;
 489                         else
 490                                 j=sk_SSL_COMP_num(s->ctx->comp_methods);
 491                         *(p++)=1+j;
 492                         for (i=0; i<j; i++)
 493                                 {
 494                                 comp=sk_SSL_COMP_value(s->ctx->comp_methods,i);
 495                                 *(p++)=comp->id;
 496                                 }
 497 #endif
 498                         *(p++)=0; /* Add the NULL method */
 499
 500 #ifndef OPENSSL_NO_TLSEXT
 501                         /* TLS extensions*/
 502                         if (ssl_prepare_clienthello_tlsext(s) <= 0)
 503                                 {
 504                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
 505                                 return -1;
 506                                 }
 507                         if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
 508                                 {
 509                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 510                                 return -1;
 511                                 }
 512 #endif
 513
 514                         l = p-d;
 515
 516                         /* fill in 4-byte handshake header */
 517                         d=&(buf[5]);
 518                         *(d++)=SSL3_MT_CLIENT_HELLO;
 519                         l2n3(l,d);
 520
 521                         l += 4;
 522
 523                         if (l > SSL3_RT_MAX_PLAIN_LENGTH)
 524                                 {
 525                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 526                                 return -1;
 527                                 }
 528
 529                         /* fill in 5-byte record header */
 530                         d=buf;
 531                         *(d++) = SSL3_RT_HANDSHAKE;
 532                         *(d++) = version_major;
 533                         /* Some servers hang if we use long client hellos
 534                          * and a record number > TLS 1.0.
 535                          */
 536                         if (TLS1_get_client_version(s) > TLS1_VERSION)
 537                                 *(d++) = 1;
 538                         else
 539                                 *(d++) = version_minor;
 540                         s2n((int)l,d);
 541
 542                         /* number of bytes to write */
 543                         s->init_num=p-buf;
 544                         s->init_off=0;
 545
 546                         ssl3_finish_mac(s,&(buf[5]), s->init_num - 5);
 547                         }
 548
 549                 s->state=SSL23_ST_CW_CLNT_HELLO_B;
 550                 s->init_off=0;
 551                 }
 552
 553         /* SSL3_ST_CW_CLNT_HELLO_B */
 554         ret = ssl23_write_bytes(s);
 555
 556         if ((ret >= 2) && s->msg_callback)
 557                 {
 558                 /* Client Hello has been sent; tell msg_callback */
 559
 560                 if (ssl2_compat)
 561                         s->msg_callback(1, SSL2_VERSION, 0, s->init_buf->data+2, ret-2, s, s->msg_callback_arg);
 562                 else
 563                         s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg);
 564                 }
 565
 566         return ret;
 567         }
 568
 569 static int ssl23_get_server_hello(SSL *s)
 570         {
 571         char buf[8];
 572         unsigned char *p;
 573         int i;
 574         int n;
 575
 576         n=ssl23_read_bytes(s,7);
 577
 578         if (n != 7) return(n);
 579         p=s->packet;
 580
 581         memcpy(buf,p,n);
 582
 583         if ((p[0] & 0x80) && (p[2] == SSL2_MT_SERVER_HELLO) &&
 584                 (p[5] == 0x00) && (p[6] == 0x02))
 585                 {
 586 #ifdef OPENSSL_NO_SSL2
 587                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 588                 goto err;
 589 #else
 590                 /* we are talking sslv2 */
 591                 /* we need to clean up the SSLv3 setup and put in the
 592                  * sslv2 stuff. */
 593                 int ch_len;
 594
 595                 if (s->options & SSL_OP_NO_SSLv2)
 596                         {
 597                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 598                         goto err;
 599                         }
 600                 if (s->s2 == NULL)
 601                         {
 602                         if (!ssl2_new(s))
 603                                 goto err;
 604                         }
 605                 else
 606                         ssl2_clear(s);
 607
 608                 if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
 609                         ch_len=SSL2_CHALLENGE_LENGTH;
 610                 else
 611                         ch_len=SSL2_MAX_CHALLENGE_LENGTH;
 612
 613                 /* write out sslv2 challenge */
 614                 /* Note that ch_len must be <= SSL3_RANDOM_SIZE (32), because
 615                    it is one of SSL2_MAX_CHALLENGE_LENGTH (32) or
 616                    SSL2_MAX_CHALLENGE_LENGTH (16), but leave the check in for
 617                    futurproofing */
 618                 i=(SSL3_RANDOM_SIZE < ch_len)
 619                         ?SSL3_RANDOM_SIZE:ch_len;
 620                 s->s2->challenge_length=i;
 621                 memcpy(s->s2->challenge,
 622                         &(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
 623
 624                 if (s->s3 != NULL) ssl3_free(s);
 625
 626                 if (!BUF_MEM_grow_clean(s->init_buf,
 627                         SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
 628                         {
 629                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,ERR_R_BUF_LIB);
 630                         goto err;
 631                         }
 632
 633                 s->state=SSL2_ST_GET_SERVER_HELLO_A;
 634                 if (!(s->client_version == SSL2_VERSION))
 635                         /* use special padding (SSL 3.0 draft/RFC 2246, App. E.2) */
 636                         s->s2->ssl2_rollback=1;
 637
 638                 /* setup the 7 bytes we have read so we get them from
 639                  * the sslv2 buffer */
 640                 s->rstate=SSL_ST_READ_HEADER;
 641                 s->packet_length=n;
 642                 s->packet= &(s->s2->rbuf[0]);
 643                 memcpy(s->packet,buf,n);
 644                 s->s2->rbuf_left=n;
 645                 s->s2->rbuf_offs=0;
 646
 647                 /* we have already written one */
 648                 s->s2->write_sequence=1;
 649
 650                 s->method=SSLv2_client_method();
 651                 s->handshake_func=s->method->ssl_connect;
 652 #endif
 653                 }
 654         else if (p[1] == SSL3_VERSION_MAJOR &&
 655                  p[2] <= TLS1_2_VERSION_MINOR &&
 656                  ((p[0] == SSL3_RT_HANDSHAKE && p[5] == SSL3_MT_SERVER_HELLO) ||
 657                   (p[0] == SSL3_RT_ALERT && p[3] == 0 && p[4] == 2)))
 658                 {
 659                 /* we have sslv3 or tls1 (server hello or alert) */
 660
 661                 if ((p[2] == SSL3_VERSION_MINOR) &&
 662                         !(s->options & SSL_OP_NO_SSLv3))
 663                         {
 664 #ifdef OPENSSL_FIPS
 665                         if(FIPS_mode())
 666                                 {
 667                                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,
 668                                         SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
 669                                 goto err;
 670                                 }
 671 #endif
 672                         s->version=SSL3_VERSION;
 673                         s->method=SSLv3_client_method();
 674                         }
 675                 else if ((p[2] == TLS1_VERSION_MINOR) &&
 676                         !(s->options & SSL_OP_NO_TLSv1))
 677                         {
 678                         s->version=TLS1_VERSION;
 679                         s->method=TLSv1_client_method();
 680                         }
 681                 else if ((p[2] == TLS1_1_VERSION_MINOR) &&
 682                         !(s->options & SSL_OP_NO_TLSv1_1))
 683                         {
 684                         s->version=TLS1_1_VERSION;
 685                         s->method=TLSv1_1_client_method();
 686                         }
 687                 else if ((p[2] == TLS1_2_VERSION_MINOR) &&
 688                         !(s->options & SSL_OP_NO_TLSv1_2))
 689                         {
 690                         s->version=TLS1_2_VERSION;
 691                         s->method=TLSv1_2_client_method();
 692                         }
 693                 else
 694                         {
 695                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 696                         goto err;
 697                         }
 698
 699                 if (p[0] == SSL3_RT_ALERT && p[5] != SSL3_AL_WARNING)
 700                         {
 701                         /* fatal alert */
 702
 703                         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 704                         int j;
 705
 706                         if (s->info_callback != NULL)
 707                                 cb=s->info_callback;
 708                         else if (s->ctx->info_callback != NULL)
 709                                 cb=s->ctx->info_callback;
 710
 711                         i=p[5];
 712                         if (cb != NULL)
 713                                 {
 714                                 j=(i<<8)|p[6];
 715                                 cb(s,SSL_CB_READ_ALERT,j);
 716                                 }
 717
 718                         if (s->msg_callback)
 719                                 s->msg_callback(0, s->version, SSL3_RT_ALERT, p+5, 2, s, s->msg_callback_arg);
 720
 721                         s->rwstate=SSL_NOTHING;
 722                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_AD_REASON_OFFSET+p[6]);
 723                         goto err;
 724                         }
 725
 726                 if (!ssl_init_wbio_buffer(s,1)) goto err;
 727
 728                 /* we are in this state */
 729                 s->state=SSL3_ST_CR_SRVR_HELLO_A;
 730
 731                 /* put the 7 bytes we have read into the input buffer
 732                  * for SSLv3 */
 733                 s->rstate=SSL_ST_READ_HEADER;
 734                 s->packet_length=n;
 735                 if (s->s3->rbuf.buf == NULL)
 736                         if (!ssl3_setup_read_buffer(s))
 737                                 goto err;
 738                 s->packet= &(s->s3->rbuf.buf[0]);
 739                 memcpy(s->packet,buf,n);
 740                 s->s3->rbuf.left=n;
 741                 s->s3->rbuf.offset=0;
 742
 743                 s->handshake_func=s->method->ssl_connect;
 744                 }
 745         else
 746                 {
 747                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNKNOWN_PROTOCOL);
 748                 goto err;
 749                 }
 750         s->init_num=0;
 751
 752         /* Since, if we are sending a ssl23 client hello, we are not
 753          * reusing a session-id */
 754         if (!ssl_get_new_session(s,0))
 755                 goto err;
 756
 757         return(SSL_connect(s));
 758 err:
 759         return(-1);
 760         }