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                 else if (version == SSL3_VERSION)
 360                         {
 361                         version_major = SSL3_VERSION_MAJOR;
 362                         version_minor = SSL3_VERSION_MINOR;
 363                         }
 364                 else if (version == SSL2_VERSION)
 365                         {
 366                         version_major = SSL2_VERSION_MAJOR;
 367                         version_minor = SSL2_VERSION_MINOR;
 368                         }
 369                 else
 370                         {
 371                         SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_PROTOCOLS_AVAILABLE);
 372                         return(-1);
 373                         }
 374
 375                 s->client_version = version;
 376
 377                 if (ssl2_compat)
 378                         {
 379                         /* create SSL 2.0 compatible Client Hello */
 380
 381                         /* two byte record header will be written last */
 382                         d = &(buf[2]);
 383                         p = d + 9; /* leave space for message type, version, individual length fields */
 384
 385                         *(d++) = SSL2_MT_CLIENT_HELLO;
 386                         *(d++) = version_major;
 387                         *(d++) = version_minor;
 388
 389                         /* Ciphers supported */
 390                         i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),p,0);
 391                         if (i == 0)
 392                                 {
 393                                 /* no ciphers */
 394                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
 395                                 return -1;
 396                                 }
 397                         s2n(i,d);
 398                         p+=i;
 399
 400                         /* put in the session-id length (zero since there is no reuse) */
 401 #if 0
 402                         s->session->session_id_length=0;
 403 #endif
 404                         s2n(0,d);
 405
 406                         if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
 407                                 ch_len=SSL2_CHALLENGE_LENGTH;
 408                         else
 409                                 ch_len=SSL2_MAX_CHALLENGE_LENGTH;
 410
 411                         /* write out sslv2 challenge */
 412                         /* Note that ch_len must be <= SSL3_RANDOM_SIZE (32),
 413                            because it is one of SSL2_MAX_CHALLENGE_LENGTH (32)
 414                            or SSL2_MAX_CHALLENGE_LENGTH (16), but leave the
 415                            check in for futurproofing */
 416                         if (SSL3_RANDOM_SIZE < ch_len)
 417                                 i=SSL3_RANDOM_SIZE;
 418                         else
 419                                 i=ch_len;
 420                         s2n(i,d);
 421                         memset(&(s->s3->client_random[0]),0,SSL3_RANDOM_SIZE);
 422                         if (RAND_pseudo_bytes(&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i) <= 0)
 423                                 return -1;
 424
 425                         memcpy(p,&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
 426                         p+=i;
 427
 428                         i= p- &(buf[2]);
 429                         buf[0]=((i>>8)&0xff)|0x80;
 430                         buf[1]=(i&0xff);
 431
 432                         /* number of bytes to write */
 433                         s->init_num=i+2;
 434                         s->init_off=0;
 435
 436                         ssl3_finish_mac(s,&(buf[2]),i);
 437                         }
 438                 else
 439                         {
 440                         /* create Client Hello in SSL 3.0/TLS 1.0 format */
 441
 442                         /* do the record header (5 bytes) and handshake message header (4 bytes) last */
 443                         d = p = &(buf[9]);
 444
 445                         *(p++) = version_major;
 446                         *(p++) = version_minor;
 447
 448                         /* Random stuff */
 449                         memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
 450                         p += SSL3_RANDOM_SIZE;
 451
 452                         /* Session ID (zero since there is no reuse) */
 453                         *(p++) = 0;
 454
 455                         /* Ciphers supported (using SSL 3.0/TLS 1.0 format) */
 456                         i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),&(p[2]),ssl3_put_cipher_by_char);
 457                         if (i == 0)
 458                                 {
 459                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
 460                                 return -1;
 461                                 }
 462                         s2n(i,p);
 463                         p+=i;
 464
 465                         /* COMPRESSION */
 466 #ifdef OPENSSL_NO_COMP
 467                         *(p++)=1;
 468 #else
 469                         if ((s->options & SSL_OP_NO_COMPRESSION)
 470                                                 || !s->ctx->comp_methods)
 471                                 j=0;
 472                         else
 473                                 j=sk_SSL_COMP_num(s->ctx->comp_methods);
 474                         *(p++)=1+j;
 475                         for (i=0; i<j; i++)
 476                                 {
 477                                 comp=sk_SSL_COMP_value(s->ctx->comp_methods,i);
 478                                 *(p++)=comp->id;
 479                                 }
 480 #endif
 481                         *(p++)=0; /* Add the NULL method */
 482
 483 #ifndef OPENSSL_NO_TLSEXT
 484                         /* TLS extensions*/
 485                         if (ssl_prepare_clienthello_tlsext(s) <= 0)
 486                                 {
 487                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
 488                                 return -1;
 489                                 }
 490                         if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
 491                                 {
 492                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 493                                 return -1;
 494                                 }
 495 #endif
 496
 497                         l = p-d;
 498
 499                         /* fill in 4-byte handshake header */
 500                         d=&(buf[5]);
 501                         *(d++)=SSL3_MT_CLIENT_HELLO;
 502                         l2n3(l,d);
 503
 504                         l += 4;
 505
 506                         if (l > SSL3_RT_MAX_PLAIN_LENGTH)
 507                                 {
 508                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 509                                 return -1;
 510                                 }
 511
 512                         /* fill in 5-byte record header */
 513                         d=buf;
 514                         *(d++) = SSL3_RT_HANDSHAKE;
 515                         *(d++) = version_major;
 516                         *(d++) = version_minor; /* arguably we should send the *lowest* suported version here
 517                                                  * (indicating, e.g., TLS 1.0 in "SSL 3.0 format") */
 518                         s2n((int)l,d);
 519
 520                         /* number of bytes to write */
 521                         s->init_num=p-buf;
 522                         s->init_off=0;
 523
 524                         ssl3_finish_mac(s,&(buf[5]), s->init_num - 5);
 525                         }
 526
 527                 s->state=SSL23_ST_CW_CLNT_HELLO_B;
 528                 s->init_off=0;
 529                 }
 530
 531         /* SSL3_ST_CW_CLNT_HELLO_B */
 532         ret = ssl23_write_bytes(s);
 533
 534         if ((ret >= 2) && s->msg_callback)
 535                 {
 536                 /* Client Hello has been sent; tell msg_callback */
 537
 538                 if (ssl2_compat)
 539                         s->msg_callback(1, SSL2_VERSION, 0, s->init_buf->data+2, ret-2, s, s->msg_callback_arg);
 540                 else
 541                         s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg);
 542                 }
 543
 544         return ret;
 545         }
 546
 547 static int ssl23_get_server_hello(SSL *s)
 548         {
 549         char buf[8];
 550         unsigned char *p;
 551         int i;
 552         int n;
 553
 554         n=ssl23_read_bytes(s,7);
 555
 556         if (n != 7) return(n);
 557         p=s->packet;
 558
 559         memcpy(buf,p,n);
 560
 561         if ((p[0] & 0x80) && (p[2] == SSL2_MT_SERVER_HELLO) &&
 562                 (p[5] == 0x00) && (p[6] == 0x02))
 563                 {
 564 #ifdef OPENSSL_NO_SSL2
 565                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 566                 goto err;
 567 #else
 568                 /* we are talking sslv2 */
 569                 /* we need to clean up the SSLv3 setup and put in the
 570                  * sslv2 stuff. */
 571                 int ch_len;
 572
 573                 if (s->options & SSL_OP_NO_SSLv2)
 574                         {
 575                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 576                         goto err;
 577                         }
 578                 if (s->s2 == NULL)
 579                         {
 580                         if (!ssl2_new(s))
 581                                 goto err;
 582                         }
 583                 else
 584                         ssl2_clear(s);
 585
 586                 if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
 587                         ch_len=SSL2_CHALLENGE_LENGTH;
 588                 else
 589                         ch_len=SSL2_MAX_CHALLENGE_LENGTH;
 590
 591                 /* write out sslv2 challenge */
 592                 /* Note that ch_len must be <= SSL3_RANDOM_SIZE (32), because
 593                    it is one of SSL2_MAX_CHALLENGE_LENGTH (32) or
 594                    SSL2_MAX_CHALLENGE_LENGTH (16), but leave the check in for
 595                    futurproofing */
 596                 i=(SSL3_RANDOM_SIZE < ch_len)
 597                         ?SSL3_RANDOM_SIZE:ch_len;
 598                 s->s2->challenge_length=i;
 599                 memcpy(s->s2->challenge,
 600                         &(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
 601
 602                 if (s->s3 != NULL) ssl3_free(s);
 603
 604                 if (!BUF_MEM_grow_clean(s->init_buf,
 605                         SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
 606                         {
 607                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,ERR_R_BUF_LIB);
 608                         goto err;
 609                         }
 610
 611                 s->state=SSL2_ST_GET_SERVER_HELLO_A;
 612                 if (!(s->client_version == SSL2_VERSION))
 613                         /* use special padding (SSL 3.0 draft/RFC 2246, App. E.2) */
 614                         s->s2->ssl2_rollback=1;
 615
 616                 /* setup the 7 bytes we have read so we get them from
 617                  * the sslv2 buffer */
 618                 s->rstate=SSL_ST_READ_HEADER;
 619                 s->packet_length=n;
 620                 s->packet= &(s->s2->rbuf[0]);
 621                 memcpy(s->packet,buf,n);
 622                 s->s2->rbuf_left=n;
 623                 s->s2->rbuf_offs=0;
 624
 625                 /* we have already written one */
 626                 s->s2->write_sequence=1;
 627
 628                 s->method=SSLv2_client_method();
 629                 s->handshake_func=s->method->ssl_connect;
 630 #endif
 631                 }
 632         else if (p[1] == SSL3_VERSION_MAJOR &&
 633                  p[2] <= TLS1_2_VERSION_MINOR &&
 634                  ((p[0] == SSL3_RT_HANDSHAKE && p[5] == SSL3_MT_SERVER_HELLO) ||
 635                   (p[0] == SSL3_RT_ALERT && p[3] == 0 && p[4] == 2)))
 636                 {
 637                 /* we have sslv3 or tls1 (server hello or alert) */
 638
 639                 if ((p[2] == SSL3_VERSION_MINOR) &&
 640                         !(s->options & SSL_OP_NO_SSLv3))
 641                         {
 642                         s->version=SSL3_VERSION;
 643                         s->method=SSLv3_client_method();
 644                         }
 645                 else if ((p[2] == TLS1_VERSION_MINOR) &&
 646                         !(s->options & SSL_OP_NO_TLSv1))
 647                         {
 648                         s->version=TLS1_VERSION;
 649                         s->method=TLSv1_client_method();
 650                         }
 651                 else if ((p[2] == TLS1_1_VERSION_MINOR) &&
 652                         !(s->options & SSL_OP_NO_TLSv1_1))
 653                         {
 654                         s->version=TLS1_1_VERSION;
 655                         s->method=TLSv1_1_client_method();
 656                         }
 657                 else if ((p[2] == TLS1_2_VERSION_MINOR) &&
 658                         !(s->options & SSL_OP_NO_TLSv1_2))
 659                         {
 660                         s->version=TLS1_2_VERSION;
 661                         s->method=TLSv1_2_client_method();
 662                         }
 663                 else
 664                         {
 665                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 666                         goto err;
 667                         }
 668
 669                 if (p[0] == SSL3_RT_ALERT && p[5] != SSL3_AL_WARNING)
 670                         {
 671                         /* fatal alert */
 672
 673                         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 674                         int j;
 675
 676                         if (s->info_callback != NULL)
 677                                 cb=s->info_callback;
 678                         else if (s->ctx->info_callback != NULL)
 679                                 cb=s->ctx->info_callback;
 680
 681                         i=p[5];
 682                         if (cb != NULL)
 683                                 {
 684                                 j=(i<<8)|p[6];
 685                                 cb(s,SSL_CB_READ_ALERT,j);
 686                                 }
 687
 688                         if (s->msg_callback)
 689                                 s->msg_callback(0, s->version, SSL3_RT_ALERT, p+5, 2, s, s->msg_callback_arg);
 690
 691                         s->rwstate=SSL_NOTHING;
 692                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_AD_REASON_OFFSET+p[6]);
 693                         goto err;
 694                         }
 695
 696                 if (!ssl_init_wbio_buffer(s,1)) goto err;
 697
 698                 /* we are in this state */
 699                 s->state=SSL3_ST_CR_SRVR_HELLO_A;
 700
 701                 /* put the 7 bytes we have read into the input buffer
 702                  * for SSLv3 */
 703                 s->rstate=SSL_ST_READ_HEADER;
 704                 s->packet_length=n;
 705                 if (s->s3->rbuf.buf == NULL)
 706                         if (!ssl3_setup_read_buffer(s))
 707                                 goto err;
 708                 s->packet= &(s->s3->rbuf.buf[0]);
 709                 memcpy(s->packet,buf,n);
 710                 s->s3->rbuf.left=n;
 711                 s->s3->rbuf.offset=0;
 712
 713                 s->handshake_func=s->method->ssl_connect;
 714                 }
 715         else
 716                 {
 717                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNKNOWN_PROTOCOL);
 718                 goto err;
 719                 }
 720         s->init_num=0;
 721
 722         /* Since, if we are sending a ssl23 client hello, we are not
 723          * reusing a session-id */
 724         if (!ssl_get_new_session(s,0))
 725                 goto err;
 726
 727         return(SSL_connect(s));
 728 err:
 729         return(-1);
 730         }