src/third_party/boringssl/src/ssl/s23_clnt.c

   1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   2  * All rights reserved.
   3  *
   4  * This package is an SSL implementation written
   5  * by Eric Young (eay@cryptsoft.com).
   6  * The implementation was written so as to conform with Netscapes SSL.
   7  *
   8  * This library is free for commercial and non-commercial use as long as
   9  * the following conditions are aheared to.  The following conditions
  10  * apply to all code found in this distribution, be it the RC4, RSA,
  11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  12  * included with this distribution is covered by the same copyright terms
  13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  14  *
  15  * Copyright remains Eric Young's, and as such any Copyright notices in
  16  * the code are not to be removed.
  17  * If this package is used in a product, Eric Young should be given attribution
  18  * as the author of the parts of the library used.
  19  * This can be in the form of a textual message at program startup or
  20  * in documentation (online or textual) provided with the package.
  21  *
  22  * Redistribution and use in source and binary forms, with or without
  23  * modification, are permitted provided that the following conditions
  24  * are met:
  25  * 1. Redistributions of source code must retain the copyright
  26  *    notice, this list of conditions and the following disclaimer.
  27  * 2. Redistributions in binary form must reproduce the above copyright
  28  *    notice, this list of conditions and the following disclaimer in the
  29  *    documentation and/or other materials provided with the distribution.
  30  * 3. All advertising materials mentioning features or use of this software
  31  *    must display the following acknowledgement:
  32  *    "This product includes cryptographic software written by
  33  *     Eric Young (eay@cryptsoft.com)"
  34  *    The word 'cryptographic' can be left out if the rouines from the library
  35  *    being used are not cryptographic related :-).
  36  * 4. If you include any Windows specific code (or a derivative thereof) from
  37  *    the apps directory (application code) you must include an acknowledgement:
  38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  50  * SUCH DAMAGE.
  51  *
  52  * The licence and distribution terms for any publically available version or
  53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  54  * copied and put under another distribution licence
  55  * [including the GNU Public Licence.]
  56  */
  57 /* ====================================================================
  58  * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
  59  *
  60  * Redistribution and use in source and binary forms, with or without
  61  * modification, are permitted provided that the following conditions
  62  * are met:
  63  *
  64  * 1. Redistributions of source code must retain the above copyright
  65  *    notice, this list of conditions and the following disclaimer.
  66  *
  67  * 2. Redistributions in binary form must reproduce the above copyright
  68  *    notice, this list of conditions and the following disclaimer in
  69  *    the documentation and/or other materials provided with the
  70  *    distribution.
  71  *
  72  * 3. All advertising materials mentioning features or use of this
  73  *    software must display the following acknowledgment:
  74  *    "This product includes software developed by the OpenSSL Project
  75  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  76  *
  77  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  78  *    endorse or promote products derived from this software without
  79  *    prior written permission. For written permission, please contact
  80  *    openssl-core@openssl.org.
  81  *
  82  * 5. Products derived from this software may not be called "OpenSSL"
  83  *    nor may "OpenSSL" appear in their names without prior written
  84  *    permission of the OpenSSL Project.
  85  *
  86  * 6. Redistributions of any form whatsoever must retain the following
  87  *    acknowledgment:
  88  *    "This product includes software developed by the OpenSSL Project
  89  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  90  *
  91  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  92  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  93  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  94  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  95  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  96  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  97  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  98  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  99  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 100  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 101  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 102  * OF THE POSSIBILITY OF SUCH DAMAGE.
 103  * ====================================================================
 104  *
 105  * This product includes cryptographic software written by Eric Young
 106  * (eay@cryptsoft.com).  This product includes software written by Tim
 107  * Hudson (tjh@cryptsoft.com). */
 108
 109 #include <stdio.h>
 110
 111 #include <openssl/buf.h>
 112 #include <openssl/err.h>
 113 #include <openssl/evp.h>
 114 #include <openssl/obj.h>
 115 #include <openssl/rand.h>
 116
 117 #include "ssl_locl.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         if (ver == SSL3_VERSION)
 125                 return(SSLv3_client_method());
 126         else if (ver == TLS1_VERSION)
 127                 return(TLSv1_client_method());
 128         else if (ver == TLS1_1_VERSION)
 129                 return(TLSv1_1_client_method());
 130         else if (ver == TLS1_2_VERSION)
 131                 return(TLSv1_2_client_method());
 132         else
 133                 return(NULL);
 134         }
 135
 136 IMPLEMENT_ssl23_meth_func(SSLv23_client_method,
 137                         ssl_undefined_function,
 138                         ssl23_connect,
 139                         ssl23_get_client_method)
 140
 141 int ssl23_connect(SSL *s)
 142         {
 143         BUF_MEM *buf=NULL;
 144         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 145         int ret= -1;
 146         int new_state,state;
 147
 148         ERR_clear_error();
 149         ERR_clear_system_error();
 150
 151         if (s->info_callback != NULL)
 152                 cb=s->info_callback;
 153         else if (s->ctx->info_callback != NULL)
 154                 cb=s->ctx->info_callback;
 155
 156         s->in_handshake++;
 157         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 158
 159         for (;;)
 160                 {
 161                 state=s->state;
 162
 163                 switch(s->state)
 164                         {
 165                 case SSL_ST_BEFORE:
 166                 case SSL_ST_CONNECT:
 167                 case SSL_ST_BEFORE|SSL_ST_CONNECT:
 168                 case SSL_ST_OK|SSL_ST_CONNECT:
 169
 170                         if (s->session != NULL)
 171                                 {
 172                                 OPENSSL_PUT_ERROR(SSL, ssl23_connect, SSL_R_SSL23_DOING_SESSION_ID_REUSE);
 173                                 ret= -1;
 174                                 goto end;
 175                                 }
 176                         s->server=0;
 177                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 178
 179                         /* s->version=TLS1_VERSION; */
 180                         s->type=SSL_ST_CONNECT;
 181
 182                         if (s->init_buf == NULL)
 183                                 {
 184                                 if ((buf=BUF_MEM_new()) == NULL)
 185                                         {
 186                                         ret= -1;
 187                                         goto end;
 188                                         }
 189                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 190                                         {
 191                                         ret= -1;
 192                                         goto end;
 193                                         }
 194                                 s->init_buf=buf;
 195                                 buf=NULL;
 196                                 }
 197
 198                         if (!ssl3_setup_buffers(s)) { ret= -1; goto end; }
 199
 200                         ssl3_init_finished_mac(s);
 201
 202                         s->state=SSL23_ST_CW_CLNT_HELLO_A;
 203                         s->ctx->stats.sess_connect++;
 204                         s->init_num=0;
 205                         break;
 206
 207                 case SSL23_ST_CW_CLNT_HELLO_A:
 208                 case SSL23_ST_CW_CLNT_HELLO_B:
 209
 210                         s->shutdown=0;
 211                         ret=ssl23_client_hello(s);
 212                         if (ret <= 0) goto end;
 213                         s->state=SSL23_ST_CR_SRVR_HELLO_A;
 214                         s->init_num=0;
 215
 216                         break;
 217
 218                 case SSL23_ST_CR_SRVR_HELLO_A:
 219                 case SSL23_ST_CR_SRVR_HELLO_B:
 220                         ret=ssl23_get_server_hello(s);
 221                         if (ret >= 0) cb=NULL;
 222                         goto end;
 223                         /* break; */
 224
 225                 default:
 226                         OPENSSL_PUT_ERROR(SSL, ssl23_connect, SSL_R_UNKNOWN_STATE);
 227                         ret= -1;
 228                         goto end;
 229                         /* break; */
 230                         }
 231
 232                 if (s->debug) { (void)BIO_flush(s->wbio); }
 233
 234                 if ((cb != NULL) && (s->state != state))
 235                         {
 236                         new_state=s->state;
 237                         s->state=state;
 238                         cb(s,SSL_CB_CONNECT_LOOP,1);
 239                         s->state=new_state;
 240                         }
 241                 }
 242 end:
 243         s->in_handshake--;
 244         if (buf != NULL)
 245                 BUF_MEM_free(buf);
 246         if (cb != NULL)
 247                 cb(s,SSL_CB_CONNECT_EXIT,ret);
 248         return(ret);
 249         }
 250
 251 /* Fill a ClientRandom or ServerRandom field of length len. Returns <= 0
 252  * on failure, 1 on success. */
 253 int ssl_fill_hello_random(SSL *s, int server, unsigned char *result, int len)
 254         {
 255                 int send_time = 0;
 256                 if (len < 4)
 257                         return 0;
 258                 if (server)
 259                         send_time = (s->mode & SSL_MODE_SEND_SERVERHELLO_TIME) != 0;
 260                 else
 261                         send_time = (s->mode & SSL_MODE_SEND_CLIENTHELLO_TIME) != 0;
 262                 if (send_time)
 263                         {
 264                         unsigned long Time = (unsigned long)time(NULL);
 265                         unsigned char *p = result;
 266                         l2n(Time, p);
 267                         return RAND_pseudo_bytes(p, len-4);
 268                         }
 269                 else
 270                         return RAND_pseudo_bytes(result, len);
 271         }
 272
 273 static int ssl23_client_hello(SSL *s)
 274         {
 275         unsigned char *buf;
 276         unsigned char *p,*d;
 277         int i;
 278         unsigned long l;
 279         int version = 0, version_major, version_minor;
 280         int ret;
 281         unsigned long mask, options = s->options;
 282
 283         /*
 284          * SSL_OP_NO_X disables all protocols above X *if* there are
 285          * some protocols below X enabled. This is required in order
 286          * to maintain "version capability" vector contiguous. So
 287          * that if application wants to disable TLS1.0 in favour of
 288          * TLS1>=1, it would be insufficient to pass SSL_NO_TLSv1, the
 289          * answer is SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2.
 290          */
 291         mask =  SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1
 292 #if !defined(OPENSSL_NO_SSL3)
 293                 |SSL_OP_NO_SSLv3
 294 #endif
 295                 ;
 296 #if !defined(OPENSSL_NO_TLS1_2_CLIENT)
 297         version = TLS1_2_VERSION;
 298
 299         if ((options & SSL_OP_NO_TLSv1_2) && (options & mask) != mask)
 300                 version = TLS1_1_VERSION;
 301 #else
 302         version = TLS1_1_VERSION;
 303 #endif
 304         mask &= ~SSL_OP_NO_TLSv1_1;
 305         if ((options & SSL_OP_NO_TLSv1_1) && (options & mask) != mask)
 306                 version = TLS1_VERSION;
 307         mask &= ~SSL_OP_NO_TLSv1;
 308 #if !defined(OPENSSL_NO_SSL3)
 309         if ((options & SSL_OP_NO_TLSv1) && (options & mask) != mask)
 310                 version = SSL3_VERSION;
 311         mask &= ~SSL_OP_NO_SSLv3;
 312 #endif
 313
 314         buf=(unsigned char *)s->init_buf->data;
 315         if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
 316                 {
 317 #if 0
 318                 /* don't reuse session-id's */
 319                 if (!ssl_get_new_session(s,0))
 320                         {
 321                         return(-1);
 322                         }
 323 #endif
 324
 325                 p=s->s3->client_random;
 326                 if (ssl_fill_hello_random(s, 0, p, SSL3_RANDOM_SIZE) <= 0)
 327                         return -1;
 328
 329                 if (version == TLS1_2_VERSION)
 330                         {
 331                         version_major = TLS1_2_VERSION_MAJOR;
 332                         version_minor = TLS1_2_VERSION_MINOR;
 333                         }
 334                 else if (tls1_suiteb(s))
 335                         {
 336                         OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_ONLY_TLS_1_2_ALLOWED_IN_SUITEB_MODE);
 337                         return -1;
 338                         }
 339                 else if (version == TLS1_1_VERSION)
 340                         {
 341                         version_major = TLS1_1_VERSION_MAJOR;
 342                         version_minor = TLS1_1_VERSION_MINOR;
 343                         }
 344                 else if (version == TLS1_VERSION)
 345                         {
 346                         version_major = TLS1_VERSION_MAJOR;
 347                         version_minor = TLS1_VERSION_MINOR;
 348                         }
 349                 else if (version == SSL3_VERSION)
 350                         {
 351                         version_major = SSL3_VERSION_MAJOR;
 352                         version_minor = SSL3_VERSION_MINOR;
 353                         }
 354                 else if (version == SSL2_VERSION)
 355                         {
 356                         version_major = SSL2_VERSION_MAJOR;
 357                         version_minor = SSL2_VERSION_MINOR;
 358                         }
 359                 else
 360                         {
 361                         OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_NO_PROTOCOLS_AVAILABLE);
 362                         return(-1);
 363                         }
 364
 365                 s->client_version = version;
 366
 367                 /* create Client Hello in SSL 3.0/TLS 1.0 format */
 368
 369                 /* do the record header (5 bytes) and handshake message
 370                  * header (4 bytes) last. Note: the final argument to
 371                  * ssl_add_clienthello_tlsext below depends on the size
 372                  * of this prefix. */
 373                 d = p = &(buf[9]);
 374
 375                 *(p++) = version_major;
 376                 *(p++) = version_minor;
 377
 378                 /* Random stuff */
 379                 memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
 380                 p += SSL3_RANDOM_SIZE;
 381
 382                 /* Session ID (zero since there is no reuse) */
 383                 *(p++) = 0;
 384
 385                 /* Ciphers supported (using SSL 3.0/TLS 1.0 format) */
 386                 i = ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), &p[2]);
 387                 if (i == 0)
 388                         {
 389                         OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_NO_CIPHERS_AVAILABLE);
 390                         return -1;
 391                         }
 392                 s2n(i,p);
 393                 p+=i;
 394
 395                 /* COMPRESSION */
 396                 *(p++)=1;
 397                 *(p++)=0; /* Add the NULL method */
 398
 399                 /* TLS extensions*/
 400                 if (ssl_prepare_clienthello_tlsext(s) <= 0)
 401                         {
 402                         OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_CLIENTHELLO_TLSEXT);
 403                         return -1;
 404                         }
 405
 406                 /* The buffer includes the 5 byte record header, so
 407                  * subtract it to compute hlen for
 408                  * ssl_add_clienthello_tlsext. */
 409                 if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, p-buf-5)) == NULL)
 410                         {
 411                         OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, ERR_R_INTERNAL_ERROR);
 412                         return -1;
 413                         }
 414
 415                 l = p-d;
 416
 417                 /* fill in 4-byte handshake header */
 418                 d=&(buf[5]);
 419                 *(d++)=SSL3_MT_CLIENT_HELLO;
 420                 l2n3(l,d);
 421
 422                 l += 4;
 423
 424                 if (l > SSL3_RT_MAX_PLAIN_LENGTH)
 425                         {
 426                         OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, ERR_R_INTERNAL_ERROR);
 427                         return -1;
 428                         }
 429
 430                 /* fill in 5-byte record header */
 431                 d=buf;
 432                 *(d++) = SSL3_RT_HANDSHAKE;
 433                 *(d++) = version_major;
 434                 /* Some servers hang if we use long client hellos
 435                  * and a record number > TLS 1.0.
 436                  */
 437                 if (TLS1_get_client_version(s) > TLS1_VERSION)
 438                         *(d++) = 1;
 439                 else
 440                         *(d++) = version_minor;
 441                 s2n((int)l,d);
 442
 443                 /* number of bytes to write */
 444                 s->init_num=p-buf;
 445                 s->init_off=0;
 446
 447                 ssl3_finish_mac(s,&(buf[5]), s->init_num - 5);
 448
 449                 s->state=SSL23_ST_CW_CLNT_HELLO_B;
 450                 s->init_off=0;
 451                 }
 452
 453         /* SSL3_ST_CW_CLNT_HELLO_B */
 454         ret = ssl23_write_bytes(s);
 455
 456         if ((ret >= 2) && s->msg_callback)
 457                 {
 458                 /* Client Hello has been sent; tell msg_callback */
 459
 460                 s->msg_callback(1, version, SSL3_RT_HEADER, s->init_buf->data, 5, s, s->msg_callback_arg);
 461                 s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg);
 462                 }
 463
 464         return ret;
 465         }
 466
 467 static int ssl23_get_server_hello(SSL *s)
 468         {
 469         char buf[8];
 470         unsigned char *p;
 471         int i;
 472         int n;
 473
 474         n=ssl23_read_bytes(s,7);
 475
 476         if (n != 7) return(n);
 477         p=s->packet;
 478
 479         memcpy(buf,p,n);
 480
 481         if ((p[0] & 0x80) && (p[2] == SSL2_MT_SERVER_HELLO) &&
 482                 (p[5] == 0x00) && (p[6] == 0x02))
 483                 {
 484                 OPENSSL_PUT_ERROR(SSL, ssl23_get_server_hello, SSL_R_UNSUPPORTED_PROTOCOL);
 485                 goto err;
 486                 }
 487         else if (p[1] == SSL3_VERSION_MAJOR &&
 488                  p[2] <= TLS1_2_VERSION_MINOR &&
 489                  ((p[0] == SSL3_RT_HANDSHAKE && p[5] == SSL3_MT_SERVER_HELLO) ||
 490                   (p[0] == SSL3_RT_ALERT && p[3] == 0 && p[4] == 2)))
 491                 {
 492                 /* we have sslv3 or tls1 (server hello or alert) */
 493
 494                 if ((p[2] == SSL3_VERSION_MINOR) &&
 495                         !(s->options & SSL_OP_NO_SSLv3))
 496                         {
 497                         s->version=SSL3_VERSION;
 498                         s->method=SSLv3_client_method();
 499                         }
 500                 else if ((p[2] == TLS1_VERSION_MINOR) &&
 501                         !(s->options & SSL_OP_NO_TLSv1))
 502                         {
 503                         s->version=TLS1_VERSION;
 504                         s->method=TLSv1_client_method();
 505                         }
 506                 else if ((p[2] == TLS1_1_VERSION_MINOR) &&
 507                         !(s->options & SSL_OP_NO_TLSv1_1))
 508                         {
 509                         s->version=TLS1_1_VERSION;
 510                         s->method=TLSv1_1_client_method();
 511                         }
 512                 else if ((p[2] == TLS1_2_VERSION_MINOR) &&
 513                         !(s->options & SSL_OP_NO_TLSv1_2))
 514                         {
 515                         s->version=TLS1_2_VERSION;
 516                         s->method=TLSv1_2_client_method();
 517                         }
 518                 else
 519                         {
 520                         OPENSSL_PUT_ERROR(SSL, ssl23_get_server_hello, SSL_R_UNSUPPORTED_PROTOCOL);
 521                         goto err;
 522                         }
 523
 524                 if (p[0] == SSL3_RT_ALERT && p[5] != SSL3_AL_WARNING)
 525                         {
 526                         /* fatal alert */
 527
 528                         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 529                         int j;
 530
 531                         if (s->info_callback != NULL)
 532                                 cb=s->info_callback;
 533                         else if (s->ctx->info_callback != NULL)
 534                                 cb=s->ctx->info_callback;
 535
 536                         i=p[5];
 537                         if (cb != NULL)
 538                                 {
 539                                 j=(i<<8)|p[6];
 540                                 cb(s,SSL_CB_READ_ALERT,j);
 541                                 }
 542
 543                         if (s->msg_callback)
 544                                 {
 545                                 s->msg_callback(0, s->version, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
 546                                 s->msg_callback(0, s->version, SSL3_RT_ALERT, p+5, 2, s, s->msg_callback_arg);
 547                                 }
 548
 549                         s->rwstate=SSL_NOTHING;
 550                         OPENSSL_PUT_ERROR(SSL, ssl23_get_server_hello, SSL_AD_REASON_OFFSET + p[6]);
 551                         goto err;
 552                         }
 553
 554                 if (!ssl_init_wbio_buffer(s,1)) goto err;
 555
 556                 /* we are in this state */
 557                 s->state=SSL3_ST_CR_SRVR_HELLO_A;
 558
 559                 /* put the 7 bytes we have read into the input buffer
 560                  * for SSLv3 */
 561                 s->rstate=SSL_ST_READ_HEADER;
 562                 s->packet_length=n;
 563                 if (s->s3->rbuf.buf == NULL)
 564                         if (!ssl3_setup_read_buffer(s))
 565                                 goto err;
 566                 s->packet= &(s->s3->rbuf.buf[0]);
 567                 memcpy(s->packet,buf,n);
 568                 s->s3->rbuf.left=n;
 569                 s->s3->rbuf.offset=0;
 570
 571                 s->handshake_func=s->method->ssl_connect;
 572                 }
 573         else
 574                 {
 575                 OPENSSL_PUT_ERROR(SSL, ssl23_get_server_hello, SSL_R_UNKNOWN_PROTOCOL);
 576                 goto err;
 577                 }
 578         s->init_num=0;
 579
 580         /* Since, if we are sending a ssl23 client hello, we are not
 581          * reusing a session-id */
 582         if (!ssl_get_new_session(s,0))
 583                 goto err;
 584
 585         return(SSL_connect(s));
 586 err:
 587         return(-1);
 588         }