ssl/s23_srvr.c

   1 /* ssl/s23_srvr.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 #ifdef OPENSSL_FIPS
 119 #include <openssl/fips.h>
 120 #endif
 121
 122 static const SSL_METHOD *ssl23_get_server_method(int ver);
 123 int ssl23_get_client_hello(SSL *s);
 124 static const SSL_METHOD *ssl23_get_server_method(int ver)
 125         {
 126 #ifndef OPENSSL_NO_SSL2
 127         if (ver == SSL2_VERSION)
 128                 return(SSLv2_server_method());
 129 #endif
 130 #ifndef OPENSSL_NO_SSL3
 131         if (ver == SSL3_VERSION)
 132                 return(SSLv3_server_method());
 133 #endif
 134         if (ver == TLS1_VERSION)
 135                 return(TLSv1_server_method());
 136         else if (ver == TLS1_1_VERSION)
 137                 return(TLSv1_1_server_method());
 138         else if (ver == TLS1_2_VERSION)
 139                 return(TLSv1_2_server_method());
 140         else
 141                 return(NULL);
 142         }
 143
 144 IMPLEMENT_ssl23_meth_func(SSLv23_server_method,
 145                         ssl23_accept,
 146                         ssl_undefined_function,
 147                         ssl23_get_server_method)
 148
 149 int ssl23_accept(SSL *s)
 150         {
 151         BUF_MEM *buf;
 152         unsigned long Time=(unsigned long)time(NULL);
 153         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 154         int ret= -1;
 155         int new_state,state;
 156
 157         RAND_add(&Time,sizeof(Time),0);
 158         ERR_clear_error();
 159         clear_sys_error();
 160
 161         if (s->info_callback != NULL)
 162                 cb=s->info_callback;
 163         else if (s->ctx->info_callback != NULL)
 164                 cb=s->ctx->info_callback;
 165
 166         s->in_handshake++;
 167         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 168
 169         for (;;)
 170                 {
 171                 state=s->state;
 172
 173                 switch(s->state)
 174                         {
 175                 case SSL_ST_BEFORE:
 176                 case SSL_ST_ACCEPT:
 177                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
 178                 case SSL_ST_OK|SSL_ST_ACCEPT:
 179
 180                         s->server=1;
 181                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 182
 183                         /* s->version=SSL3_VERSION; */
 184                         s->type=SSL_ST_ACCEPT;
 185
 186                         if (s->init_buf == NULL)
 187                                 {
 188                                 if ((buf=BUF_MEM_new()) == NULL)
 189                                         {
 190                                         ret= -1;
 191                                         goto end;
 192                                         }
 193                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 194                                         {
 195                                         BUF_MEM_free(buf);
 196                                         ret= -1;
 197                                         goto end;
 198                                         }
 199                                 s->init_buf=buf;
 200                                 }
 201
 202                         ssl3_init_finished_mac(s);
 203
 204                         s->state=SSL23_ST_SR_CLNT_HELLO_A;
 205                         s->ctx->stats.sess_accept++;
 206                         s->init_num=0;
 207                         break;
 208
 209                 case SSL23_ST_SR_CLNT_HELLO_A:
 210                 case SSL23_ST_SR_CLNT_HELLO_B:
 211
 212                         s->shutdown=0;
 213                         ret=ssl23_get_client_hello(s);
 214                         if (ret >= 0) cb=NULL;
 215                         goto end;
 216                         /* break; */
 217
 218                 default:
 219                         SSLerr(SSL_F_SSL23_ACCEPT,SSL_R_UNKNOWN_STATE);
 220                         ret= -1;
 221                         goto end;
 222                         /* break; */
 223                         }
 224
 225                 if ((cb != NULL) && (s->state != state))
 226                         {
 227                         new_state=s->state;
 228                         s->state=state;
 229                         cb(s,SSL_CB_ACCEPT_LOOP,1);
 230                         s->state=new_state;
 231                         }
 232                 }
 233 end:
 234         s->in_handshake--;
 235         if (cb != NULL)
 236                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
 237         return(ret);
 238         }
 239
 240
 241 int ssl23_get_client_hello(SSL *s)
 242         {
 243         char buf_space[11]; /* Request this many bytes in initial read.
 244                              * We can detect SSL 3.0/TLS 1.0 Client Hellos
 245                              * ('type == 3') correctly only when the following
 246                              * is in a single record, which is not guaranteed by
 247                              * the protocol specification:
 248                              * Byte  Content
 249                              *  0     type            \
 250                              *  1/2   version          > record header
 251                              *  3/4   length          /
 252                              *  5     msg_type        \
 253                              *  6-8   length           > Client Hello message
 254                              *  9/10  client_version  /
 255                              */
 256         char *buf= &(buf_space[0]);
 257         unsigned char *p,*d,*d_len,*dd;
 258         unsigned int i;
 259         unsigned int csl,sil,cl;
 260         int n=0,j;
 261         int type=0;
 262         int v[2];
 263
 264         if (s->state == SSL23_ST_SR_CLNT_HELLO_A)
 265                 {
 266                 /* read the initial header */
 267                 v[0]=v[1]=0;
 268
 269                 if (!ssl3_setup_buffers(s)) goto err;
 270
 271                 n=ssl23_read_bytes(s, sizeof buf_space);
 272                 if (n != sizeof buf_space) return(n); /* n == -1 || n == 0 */
 273
 274                 p=s->packet;
 275
 276                 memcpy(buf,p,n);
 277
 278                 if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO))
 279                         {
 280                         /*
 281                          * SSLv2 header
 282                          */
 283                         if ((p[3] == 0x00) && (p[4] == 0x02))
 284                                 {
 285                                 v[0]=p[3]; v[1]=p[4];
 286                                 /* SSLv2 */
 287                                 if (!(s->options & SSL_OP_NO_SSLv2))
 288                                         type=1;
 289                                 }
 290                         else if (p[3] == SSL3_VERSION_MAJOR)
 291                                 {
 292                                 v[0]=p[3]; v[1]=p[4];
 293                                 /* SSLv3/TLSv1 */
 294                                 if (p[4] >= TLS1_VERSION_MINOR)
 295                                         {
 296                                         if (p[4] >= TLS1_2_VERSION_MINOR &&
 297                                            !(s->options & SSL_OP_NO_TLSv1_2))
 298                                                 {
 299                                                 s->version=TLS1_2_VERSION;
 300                                                 s->state=SSL23_ST_SR_CLNT_HELLO_B;
 301                                                 }
 302                                         else if (p[4] >= TLS1_1_VERSION_MINOR &&
 303                                            !(s->options & SSL_OP_NO_TLSv1_1))
 304                                                 {
 305                                                 s->version=TLS1_1_VERSION;
 306                                                 /* type=2; */ /* done later to survive restarts */
 307                                                 s->state=SSL23_ST_SR_CLNT_HELLO_B;
 308                                                 }
 309                                         else if (!(s->options & SSL_OP_NO_TLSv1))
 310                                                 {
 311                                                 s->version=TLS1_VERSION;
 312                                                 /* type=2; */ /* done later to survive restarts */
 313                                                 s->state=SSL23_ST_SR_CLNT_HELLO_B;
 314                                                 }
 315                                         else if (!(s->options & SSL_OP_NO_SSLv3))
 316                                                 {
 317                                                 s->version=SSL3_VERSION;
 318                                                 /* type=2; */
 319                                                 s->state=SSL23_ST_SR_CLNT_HELLO_B;
 320                                                 }
 321                                         else if (!(s->options & SSL_OP_NO_SSLv2))
 322                                                 {
 323                                                 type=1;
 324                                                 }
 325                                         }
 326                                 else if (!(s->options & SSL_OP_NO_SSLv3))
 327                                         {
 328                                         s->version=SSL3_VERSION;
 329                                         /* type=2; */
 330                                         s->state=SSL23_ST_SR_CLNT_HELLO_B;
 331                                         }
 332                                 else if (!(s->options & SSL_OP_NO_SSLv2))
 333                                         type=1;
 334
 335                                 }
 336                         }
 337                 /* p[4] < 5 ... silly record length? */
 338                 else if ((p[0] == SSL3_RT_HANDSHAKE) &&
 339                          (p[1] == SSL3_VERSION_MAJOR) &&
 340                          (p[5] == SSL3_MT_CLIENT_HELLO) &&
 341                          ((p[3] == 0 && p[4] < 5)
 342                                 || (p[9] >= p[1])))
 343                         {
 344                         /*
 345                          * SSLv3 or tls1 header
 346                          */
 347
 348                         v[0]=p[1]; /* major version (= SSL3_VERSION_MAJOR) */
 349                         /* We must look at client_version inside the Client Hello message
 350                          * to get the correct minor version.
 351                          * However if we have only a pathologically small fragment of the
 352                          * Client Hello message, this would be difficult, and we'd have
 353                          * to read more records to find out.
 354                          * No known SSL 3.0 client fragments ClientHello like this,
 355                          * so we simply reject such connections to avoid
 356                          * protocol version downgrade attacks. */
 357                         if (p[3] == 0 && p[4] < 6)
 358                                 {
 359                                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL);
 360                                 goto err;
 361                                 }
 362                         /* if major version number > 3 set minor to a value
 363                          * which will use the highest version 3 we support.
 364                          * If TLS 2.0 ever appears we will need to revise
 365                          * this....
 366                          */
 367                         if (p[9] > SSL3_VERSION_MAJOR)
 368                                 v[1]=0xff;
 369                         else
 370                                 v[1]=p[10]; /* minor version according to client_version */
 371                         if (v[1] >= TLS1_VERSION_MINOR)
 372                                 {
 373                                 if (v[1] >= TLS1_2_VERSION_MINOR &&
 374                                         !(s->options & SSL_OP_NO_TLSv1_2))
 375                                         {
 376                                         s->version=TLS1_2_VERSION;
 377                                         type=3;
 378                                         }
 379                                 else if (v[1] >= TLS1_1_VERSION_MINOR &&
 380                                         !(s->options & SSL_OP_NO_TLSv1_1))
 381                                         {
 382                                         s->version=TLS1_1_VERSION;
 383                                         type=3;
 384                                         }
 385                                 else if (!(s->options & SSL_OP_NO_TLSv1))
 386                                         {
 387                                         s->version=TLS1_VERSION;
 388                                         type=3;
 389                                         }
 390                                 else if (!(s->options & SSL_OP_NO_SSLv3))
 391                                         {
 392                                         s->version=SSL3_VERSION;
 393                                         type=3;
 394                                         }
 395                                 }
 396                         else
 397                                 {
 398                                 /* client requests SSL 3.0 */
 399                                 if (!(s->options & SSL_OP_NO_SSLv3))
 400                                         {
 401                                         s->version=SSL3_VERSION;
 402                                         type=3;
 403                                         }
 404                                 else if (!(s->options & SSL_OP_NO_TLSv1))
 405                                         {
 406                                         /* we won't be able to use TLS of course,
 407                                          * but this will send an appropriate alert */
 408                                         s->version=TLS1_VERSION;
 409                                         type=3;
 410                                         }
 411                                 }
 412                         }
 413                 else if ((strncmp("GET ", (char *)p,4) == 0) ||
 414                          (strncmp("POST ",(char *)p,5) == 0) ||
 415                          (strncmp("HEAD ",(char *)p,5) == 0) ||
 416                          (strncmp("PUT ", (char *)p,4) == 0))
 417                         {
 418                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTP_REQUEST);
 419                         goto err;
 420                         }
 421                 else if (strncmp("CONNECT",(char *)p,7) == 0)
 422                         {
 423                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTPS_PROXY_REQUEST);
 424                         goto err;
 425                         }
 426                 }
 427
 428         /* ensure that TLS_MAX_VERSION is up-to-date */
 429         OPENSSL_assert(s->version <= TLS_MAX_VERSION);
 430
 431         if (s->version < TLS1_2_VERSION && tls1_suiteb(s))
 432                 {
 433                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,
 434                                 SSL_R_ONLY_TLS_1_2_ALLOWED_IN_SUITEB_MODE);
 435                 goto err;
 436                 }
 437
 438 #ifdef OPENSSL_FIPS
 439         if (FIPS_mode() && (s->version < TLS1_VERSION))
 440                 {
 441                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,
 442                                         SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
 443                 goto err;
 444                 }
 445 #endif
 446
 447         if (s->state == SSL23_ST_SR_CLNT_HELLO_B)
 448                 {
 449                 /* we have SSLv3/TLSv1 in an SSLv2 header
 450                  * (other cases skip this state) */
 451
 452                 type=2;
 453                 p=s->packet;
 454                 v[0] = p[3]; /* == SSL3_VERSION_MAJOR */
 455                 v[1] = p[4];
 456
 457                 /*-
 458                  * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
 459                  * header is sent directly on the wire, not wrapped as a TLS
 460                  * record. It's format is:
 461                  * Byte  Content
 462                  * 0-1   msg_length
 463                  * 2     msg_type
 464                  * 3-4   version
 465                  * 5-6   cipher_spec_length
 466                  * 7-8   session_id_length
 467                  * 9-10  challenge_length
 468                  * ...   ...
 469                  */
 470                 n=((p[0]&0x7f)<<8)|p[1];
 471                 if (n > (1024*4))
 472                         {
 473                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE);
 474                         goto err;
 475                         }
 476                 if (n < 9)
 477                         {
 478                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH);
 479                         goto err;
 480                         }
 481
 482                 j=ssl23_read_bytes(s,n+2);
 483                 /* We previously read 11 bytes, so if j > 0, we must have
 484                  * j == n+2 == s->packet_length. We have at least 11 valid
 485                  * packet bytes. */
 486                 if (j <= 0) return(j);
 487
 488                 ssl3_finish_mac(s, s->packet+2, s->packet_length-2);
 489
 490                 /* CLIENT-HELLO */
 491                 if (s->msg_callback)
 492                         s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg);
 493
 494                 p=s->packet;
 495                 p+=5;
 496                 n2s(p,csl);
 497                 n2s(p,sil);
 498                 n2s(p,cl);
 499                 d=(unsigned char *)s->init_buf->data;
 500                 if ((csl+sil+cl+11) != s->packet_length) /* We can't have TLS extensions in SSL 2.0 format
 501                                                           * Client Hello, can we? Error condition should be
 502                                                           * '>' otherweise */
 503                         {
 504                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH);
 505                         goto err;
 506                         }
 507
 508                 /* record header: msg_type ... */
 509                 *(d++) = SSL3_MT_CLIENT_HELLO;
 510                 /* ... and length (actual value will be written later) */
 511                 d_len = d;
 512                 d += 3;
 513
 514                 /* client_version */
 515                 *(d++) = SSL3_VERSION_MAJOR; /* == v[0] */
 516                 *(d++) = v[1];
 517
 518                 /* lets populate the random area */
 519                 /* get the challenge_length */
 520                 i=(cl > SSL3_RANDOM_SIZE)?SSL3_RANDOM_SIZE:cl;
 521                 memset(d,0,SSL3_RANDOM_SIZE);
 522                 memcpy(&(d[SSL3_RANDOM_SIZE-i]),&(p[csl+sil]),i);
 523                 d+=SSL3_RANDOM_SIZE;
 524
 525                 /* no session-id reuse */
 526                 *(d++)=0;
 527
 528                 /* ciphers */
 529                 j=0;
 530                 dd=d;
 531                 d+=2;
 532                 for (i=0; i<csl; i+=3)
 533                         {
 534                         if (p[i] != 0) continue;
 535                         *(d++)=p[i+1];
 536                         *(d++)=p[i+2];
 537                         j+=2;
 538                         }
 539                 s2n(j,dd);
 540
 541                 /* COMPRESSION */
 542                 *(d++)=1;
 543                 *(d++)=0;
 544
 545 #if 0
 546                 /* copy any remaining data with may be extensions */
 547                 p = p+csl+sil+cl;
 548                 while (p <  s->packet+s->packet_length)
 549                         {
 550                         *(d++)=*(p++);
 551                         }
 552 #endif
 553
 554                 i = (d-(unsigned char *)s->init_buf->data) - 4;
 555                 l2n3((long)i, d_len);
 556
 557                 /* get the data reused from the init_buf */
 558                 s->s3->tmp.reuse_message=1;
 559                 s->s3->tmp.message_type=SSL3_MT_CLIENT_HELLO;
 560                 s->s3->tmp.message_size=i;
 561                 }
 562
 563         /* imaginary new state (for program structure): */
 564         /* s->state = SSL23_SR_CLNT_HELLO_C */
 565
 566         if (type == 1)
 567                 {
 568 #ifdef OPENSSL_NO_SSL2
 569                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 570                 goto err;
 571 #else
 572                 /* we are talking sslv2 */
 573                 /* we need to clean up the SSLv3/TLSv1 setup and put in the
 574                  * sslv2 stuff. */
 575
 576                 if (s->s2 == NULL)
 577                         {
 578                         if (!ssl2_new(s))
 579                                 goto err;
 580                         }
 581                 else
 582                         ssl2_clear(s);
 583
 584                 if (s->s3 != NULL) ssl3_free(s);
 585
 586                 if (!BUF_MEM_grow_clean(s->init_buf,
 587                         SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
 588                         {
 589                         goto err;
 590                         }
 591
 592                 s->state=SSL2_ST_GET_CLIENT_HELLO_A;
 593                 if (s->options & SSL_OP_NO_TLSv1 && s->options & SSL_OP_NO_SSLv3)
 594                         s->s2->ssl2_rollback=0;
 595                 else
 596                         /* reject SSL 2.0 session if client supports SSL 3.0 or TLS 1.0
 597                          * (SSL 3.0 draft/RFC 2246, App. E.2) */
 598                         s->s2->ssl2_rollback=1;
 599
 600                 /* setup the n bytes we have read so we get them from
 601                  * the sslv2 buffer */
 602                 s->rstate=SSL_ST_READ_HEADER;
 603                 s->packet_length=n;
 604                 s->packet= &(s->s2->rbuf[0]);
 605                 memcpy(s->packet,buf,n);
 606                 s->s2->rbuf_left=n;
 607                 s->s2->rbuf_offs=0;
 608
 609                 s->method=SSLv2_server_method();
 610                 s->handshake_func=s->method->ssl_accept;
 611 #endif
 612                 }
 613
 614         if ((type == 2) || (type == 3))
 615                 {
 616                 /* we have SSLv3/TLSv1 (type 2: SSL2 style, type 3: SSL3/TLS style) */
 617                 const SSL_METHOD *new_method;
 618                 new_method = ssl23_get_server_method(s->version);
 619                 if (new_method == NULL)
 620                         {
 621                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 622                         goto err;
 623                         }
 624                 s->method = new_method;
 625
 626                 if (!ssl_init_wbio_buffer(s,1)) goto err;
 627
 628                 /* we are in this state */
 629                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
 630
 631                 if (type == 3)
 632                         {
 633                         /* put the 'n' bytes we have read into the input buffer
 634                          * for SSLv3 */
 635                         s->rstate=SSL_ST_READ_HEADER;
 636                         s->packet_length=n;
 637                         if (s->s3->rbuf.buf == NULL)
 638                                 if (!ssl3_setup_read_buffer(s))
 639                                         goto err;
 640
 641                         s->packet= &(s->s3->rbuf.buf[0]);
 642                         memcpy(s->packet,buf,n);
 643                         s->s3->rbuf.left=n;
 644                         s->s3->rbuf.offset=0;
 645                         }
 646                 else
 647                         {
 648                         s->packet_length=0;
 649                         s->s3->rbuf.left=0;
 650                         s->s3->rbuf.offset=0;
 651                         }
 652 #if 0 /* ssl3_get_client_hello does this */
 653                 s->client_version=(v[0]<<8)|v[1];
 654 #endif
 655                 s->handshake_func=s->method->ssl_accept;
 656                 }
 657
 658         if ((type < 1) || (type > 3))
 659                 {
 660                 /* bad, very bad */
 661                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNKNOWN_PROTOCOL);
 662                 goto err;
 663                 }
 664         s->init_num=0;
 665
 666         if (buf != buf_space) OPENSSL_free(buf);
 667         return(SSL_accept(s));
 668 err:
 669         if (buf != buf_space) OPENSSL_free(buf);
 670         return(-1);
 671         }