crypto/openssl/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 #include <stdio.h>
  60 #include "ssl_locl.h"
  61 #include <openssl/buffer.h>
  62 #include <openssl/rand.h>
  63 #include <openssl/objects.h>
  64 #include <openssl/evp.h>
  65
  66 static SSL_METHOD *ssl23_get_client_method(int ver);
  67 static int ssl23_client_hello(SSL *s);
  68 static int ssl23_get_server_hello(SSL *s);
  69 static SSL_METHOD *ssl23_get_client_method(int ver)
  70         {
  71 #ifndef OPENSSL_NO_SSL2
  72         if (ver == SSL2_VERSION)
  73                 return(SSLv2_client_method());
  74 #endif
  75 #ifndef OPENSSL_NO_SSL3
  76         if (ver == SSL3_VERSION)
  77                 return(SSLv3_client_method());
  78 #endif
  79         if (ver == TLS1_VERSION)
  80                 return(TLSv1_client_method());
  81         else
  82                 return(NULL);
  83         }
  84
  85 IMPLEMENT_ssl23_meth_func(SSLv23_client_method,
  86                         ssl_undefined_function,
  87                         ssl23_connect,
  88                         ssl23_get_client_method)
  89
  90 int ssl23_connect(SSL *s)
  91         {
  92         BUF_MEM *buf=NULL;
  93         unsigned long Time=(unsigned long)time(NULL);
  94         void (*cb)(const SSL *ssl,int type,int val)=NULL;
  95         int ret= -1;
  96         int new_state,state;
  97
  98         RAND_add(&Time,sizeof(Time),0);
  99         ERR_clear_error();
 100         clear_sys_error();
 101
 102         if (s->info_callback != NULL)
 103                 cb=s->info_callback;
 104         else if (s->ctx->info_callback != NULL)
 105                 cb=s->ctx->info_callback;
 106
 107         s->in_handshake++;
 108         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 109
 110         for (;;)
 111                 {
 112                 state=s->state;
 113
 114                 switch(s->state)
 115                         {
 116                 case SSL_ST_BEFORE:
 117                 case SSL_ST_CONNECT:
 118                 case SSL_ST_BEFORE|SSL_ST_CONNECT:
 119                 case SSL_ST_OK|SSL_ST_CONNECT:
 120
 121                         if (s->session != NULL)
 122                                 {
 123                                 SSLerr(SSL_F_SSL23_CONNECT,SSL_R_SSL23_DOING_SESSION_ID_REUSE);
 124                                 ret= -1;
 125                                 goto end;
 126                                 }
 127                         s->server=0;
 128                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 129
 130                         /* s->version=TLS1_VERSION; */
 131                         s->type=SSL_ST_CONNECT;
 132
 133                         if (s->init_buf == NULL)
 134                                 {
 135                                 if ((buf=BUF_MEM_new()) == NULL)
 136                                         {
 137                                         ret= -1;
 138                                         goto end;
 139                                         }
 140                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
 141                                         {
 142                                         ret= -1;
 143                                         goto end;
 144                                         }
 145                                 s->init_buf=buf;
 146                                 buf=NULL;
 147                                 }
 148
 149                         if (!ssl3_setup_buffers(s)) { ret= -1; goto end; }
 150
 151                         ssl3_init_finished_mac(s);
 152
 153                         s->state=SSL23_ST_CW_CLNT_HELLO_A;
 154                         s->ctx->stats.sess_connect++;
 155                         s->init_num=0;
 156                         break;
 157
 158                 case SSL23_ST_CW_CLNT_HELLO_A:
 159                 case SSL23_ST_CW_CLNT_HELLO_B:
 160
 161                         s->shutdown=0;
 162                         ret=ssl23_client_hello(s);
 163                         if (ret <= 0) goto end;
 164                         s->state=SSL23_ST_CR_SRVR_HELLO_A;
 165                         s->init_num=0;
 166
 167                         break;
 168
 169                 case SSL23_ST_CR_SRVR_HELLO_A:
 170                 case SSL23_ST_CR_SRVR_HELLO_B:
 171                         ret=ssl23_get_server_hello(s);
 172                         if (ret >= 0) cb=NULL;
 173                         goto end;
 174                         /* break; */
 175
 176                 default:
 177                         SSLerr(SSL_F_SSL23_CONNECT,SSL_R_UNKNOWN_STATE);
 178                         ret= -1;
 179                         goto end;
 180                         /* break; */
 181                         }
 182
 183                 if (s->debug) { (void)BIO_flush(s->wbio); }
 184
 185                 if ((cb != NULL) && (s->state != state))
 186                         {
 187                         new_state=s->state;
 188                         s->state=state;
 189                         cb(s,SSL_CB_CONNECT_LOOP,1);
 190                         s->state=new_state;
 191                         }
 192                 }
 193 end:
 194         s->in_handshake--;
 195         if (buf != NULL)
 196                 BUF_MEM_free(buf);
 197         if (cb != NULL)
 198                 cb(s,SSL_CB_CONNECT_EXIT,ret);
 199         return(ret);
 200         }
 201
 202
 203 static int ssl23_client_hello(SSL *s)
 204         {
 205         unsigned char *buf;
 206         unsigned char *p,*d;
 207         int i,ch_len;
 208         unsigned long Time,l;
 209         int ssl2_compat;
 210         int version = 0, version_major, version_minor;
 211 #ifndef OPENSSL_NO_COMP
 212         int j;
 213         SSL_COMP *comp;
 214 #endif
 215         int ret;
 216
 217         ssl2_compat = (s->options & SSL_OP_NO_SSLv2) ? 0 : 1;
 218
 219         if (!(s->options & SSL_OP_NO_TLSv1))
 220                 {
 221                 version = TLS1_VERSION;
 222                 }
 223         else if (!(s->options & SSL_OP_NO_SSLv3))
 224                 {
 225                 version = SSL3_VERSION;
 226                 }
 227         else if (!(s->options & SSL_OP_NO_SSLv2))
 228                 {
 229                 version = SSL2_VERSION;
 230                 }
 231 #ifndef OPENSSL_NO_TLSEXT
 232         if (version != SSL2_VERSION)
 233                 {
 234                 /* have to disable SSL 2.0 compatibility if we need TLS extensions */
 235
 236                 if (s->tlsext_hostname != NULL)
 237                         ssl2_compat = 0;
 238                 if (s->tlsext_status_type != -1)
 239                         ssl2_compat = 0;
 240                 }
 241 #endif
 242
 243         buf=(unsigned char *)s->init_buf->data;
 244         if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
 245                 {
 246 #if 0
 247                 /* don't reuse session-id's */
 248                 if (!ssl_get_new_session(s,0))
 249                         {
 250                         return(-1);
 251                         }
 252 #endif
 253
 254                 p=s->s3->client_random;
 255                 Time=(unsigned long)time(NULL);         /* Time */
 256                 l2n(Time,p);
 257                 if (RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-4) <= 0)
 258                         return -1;
 259
 260                 if (version == TLS1_VERSION)
 261                         {
 262                         version_major = TLS1_VERSION_MAJOR;
 263                         version_minor = TLS1_VERSION_MINOR;
 264                         }
 265 #ifdef OPENSSL_FIPS
 266                 else if(FIPS_mode())
 267                         {
 268                         SSLerr(SSL_F_SSL23_CLIENT_HELLO,
 269                                         SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
 270                         return -1;
 271                         }
 272 #endif
 273                 else if (version == SSL3_VERSION)
 274                         {
 275                         version_major = SSL3_VERSION_MAJOR;
 276                         version_minor = SSL3_VERSION_MINOR;
 277                         }
 278                 else if (version == SSL2_VERSION)
 279                         {
 280                         version_major = SSL2_VERSION_MAJOR;
 281                         version_minor = SSL2_VERSION_MINOR;
 282                         }
 283                 else
 284                         {
 285                         SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_PROTOCOLS_AVAILABLE);
 286                         return(-1);
 287                         }
 288
 289                 s->client_version = version;
 290
 291                 if (ssl2_compat)
 292                         {
 293                         /* create SSL 2.0 compatible Client Hello */
 294
 295                         /* two byte record header will be written last */
 296                         d = &(buf[2]);
 297                         p = d + 9; /* leave space for message type, version, individual length fields */
 298
 299                         *(d++) = SSL2_MT_CLIENT_HELLO;
 300                         *(d++) = version_major;
 301                         *(d++) = version_minor;
 302
 303                         /* Ciphers supported */
 304                         i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),p,0);
 305                         if (i == 0)
 306                                 {
 307                                 /* no ciphers */
 308                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
 309                                 return -1;
 310                                 }
 311                         s2n(i,d);
 312                         p+=i;
 313
 314                         /* put in the session-id length (zero since there is no reuse) */
 315 #if 0
 316                         s->session->session_id_length=0;
 317 #endif
 318                         s2n(0,d);
 319
 320                         if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
 321                                 ch_len=SSL2_CHALLENGE_LENGTH;
 322                         else
 323                                 ch_len=SSL2_MAX_CHALLENGE_LENGTH;
 324
 325                         /* write out sslv2 challenge */
 326                         if (SSL3_RANDOM_SIZE < ch_len)
 327                                 i=SSL3_RANDOM_SIZE;
 328                         else
 329                                 i=ch_len;
 330                         s2n(i,d);
 331                         memset(&(s->s3->client_random[0]),0,SSL3_RANDOM_SIZE);
 332                         if (RAND_pseudo_bytes(&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i) <= 0)
 333                                 return -1;
 334
 335                         memcpy(p,&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
 336                         p+=i;
 337
 338                         i= p- &(buf[2]);
 339                         buf[0]=((i>>8)&0xff)|0x80;
 340                         buf[1]=(i&0xff);
 341
 342                         /* number of bytes to write */
 343                         s->init_num=i+2;
 344                         s->init_off=0;
 345
 346                         ssl3_finish_mac(s,&(buf[2]),i);
 347                         }
 348                 else
 349                         {
 350                         /* create Client Hello in SSL 3.0/TLS 1.0 format */
 351
 352                         /* do the record header (5 bytes) and handshake message header (4 bytes) last */
 353                         d = p = &(buf[9]);
 354
 355                         *(p++) = version_major;
 356                         *(p++) = version_minor;
 357
 358                         /* Random stuff */
 359                         memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
 360                         p += SSL3_RANDOM_SIZE;
 361
 362                         /* Session ID (zero since there is no reuse) */
 363                         *(p++) = 0;
 364
 365                         /* Ciphers supported (using SSL 3.0/TLS 1.0 format) */
 366                         i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),&(p[2]),ssl3_put_cipher_by_char);
 367                         if (i == 0)
 368                                 {
 369                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
 370                                 return -1;
 371                                 }
 372                         s2n(i,p);
 373                         p+=i;
 374 #ifdef OPENSSL_NO_COMP
 375                         *(p++)=1;
 376 #else
 377                         /* COMPRESSION */
 378                         if (s->ctx->comp_methods == NULL)
 379                                 j=0;
 380                         else
 381                                 j=sk_SSL_COMP_num(s->ctx->comp_methods);
 382                         *(p++)=1+j;
 383                         for (i=0; i<j; i++)
 384                                 {
 385                                 comp=sk_SSL_COMP_value(s->ctx->comp_methods,i);
 386                                 *(p++)=comp->id;
 387                                 }
 388 #endif
 389                         *(p++)=0; /* Add the NULL method */
 390 #ifndef OPENSSL_NO_TLSEXT
 391                         if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
 392                                 {
 393                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 394                                 return -1;
 395                                 }
 396 #endif
 397
 398                         l = p-d;
 399                         *p = 42;
 400
 401                         /* fill in 4-byte handshake header */
 402                         d=&(buf[5]);
 403                         *(d++)=SSL3_MT_CLIENT_HELLO;
 404                         l2n3(l,d);
 405
 406                         l += 4;
 407
 408                         if (l > SSL3_RT_MAX_PLAIN_LENGTH)
 409                                 {
 410                                 SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 411                                 return -1;
 412                                 }
 413
 414                         /* fill in 5-byte record header */
 415                         d=buf;
 416                         *(d++) = SSL3_RT_HANDSHAKE;
 417                         *(d++) = version_major;
 418                         *(d++) = version_minor; /* arguably we should send the *lowest* suported version here
 419                                                  * (indicating, e.g., TLS 1.0 in "SSL 3.0 format") */
 420                         s2n((int)l,d);
 421
 422                         /* number of bytes to write */
 423                         s->init_num=p-buf;
 424                         s->init_off=0;
 425
 426                         ssl3_finish_mac(s,&(buf[5]), s->init_num - 5);
 427                         }
 428
 429                 s->state=SSL23_ST_CW_CLNT_HELLO_B;
 430                 s->init_off=0;
 431                 }
 432
 433         /* SSL3_ST_CW_CLNT_HELLO_B */
 434         ret = ssl23_write_bytes(s);
 435
 436         if ((ret >= 2) && s->msg_callback)
 437                 {
 438                 /* Client Hello has been sent; tell msg_callback */
 439
 440                 if (ssl2_compat)
 441                         s->msg_callback(1, SSL2_VERSION, 0, s->init_buf->data+2, ret-2, s, s->msg_callback_arg);
 442                 else
 443                         s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg);
 444                 }
 445
 446         return ret;
 447         }
 448
 449 static int ssl23_get_server_hello(SSL *s)
 450         {
 451         char buf[8];
 452         unsigned char *p;
 453         int i;
 454         int n;
 455
 456         n=ssl23_read_bytes(s,7);
 457
 458         if (n != 7) return(n);
 459         p=s->packet;
 460
 461         memcpy(buf,p,n);
 462
 463         if ((p[0] & 0x80) && (p[2] == SSL2_MT_SERVER_HELLO) &&
 464                 (p[5] == 0x00) && (p[6] == 0x02))
 465                 {
 466 #ifdef OPENSSL_NO_SSL2
 467                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 468                 goto err;
 469 #else
 470                 /* we are talking sslv2 */
 471                 /* we need to clean up the SSLv3 setup and put in the
 472                  * sslv2 stuff. */
 473                 int ch_len;
 474
 475                 if (s->options & SSL_OP_NO_SSLv2)
 476                         {
 477                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 478                         goto err;
 479                         }
 480                 if (s->s2 == NULL)
 481                         {
 482                         if (!ssl2_new(s))
 483                                 goto err;
 484                         }
 485                 else
 486                         ssl2_clear(s);
 487
 488                 if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
 489                         ch_len=SSL2_CHALLENGE_LENGTH;
 490                 else
 491                         ch_len=SSL2_MAX_CHALLENGE_LENGTH;
 492
 493                 /* write out sslv2 challenge */
 494                 i=(SSL3_RANDOM_SIZE < ch_len)
 495                         ?SSL3_RANDOM_SIZE:ch_len;
 496                 s->s2->challenge_length=i;
 497                 memcpy(s->s2->challenge,
 498                         &(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
 499
 500                 if (s->s3 != NULL) ssl3_free(s);
 501
 502                 if (!BUF_MEM_grow_clean(s->init_buf,
 503                         SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
 504                         {
 505                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,ERR_R_BUF_LIB);
 506                         goto err;
 507                         }
 508
 509                 s->state=SSL2_ST_GET_SERVER_HELLO_A;
 510                 if (!(s->client_version == SSL2_VERSION))
 511                         /* use special padding (SSL 3.0 draft/RFC 2246, App. E.2) */
 512                         s->s2->ssl2_rollback=1;
 513
 514                 /* setup the 7 bytes we have read so we get them from
 515                  * the sslv2 buffer */
 516                 s->rstate=SSL_ST_READ_HEADER;
 517                 s->packet_length=n;
 518                 s->packet= &(s->s2->rbuf[0]);
 519                 memcpy(s->packet,buf,n);
 520                 s->s2->rbuf_left=n;
 521                 s->s2->rbuf_offs=0;
 522
 523                 /* we have already written one */
 524                 s->s2->write_sequence=1;
 525
 526                 s->method=SSLv2_client_method();
 527                 s->handshake_func=s->method->ssl_connect;
 528 #endif
 529                 }
 530         else if (p[1] == SSL3_VERSION_MAJOR &&
 531                  ((p[2] == SSL3_VERSION_MINOR) ||
 532                   (p[2] == TLS1_VERSION_MINOR)) &&
 533                  ((p[0] == SSL3_RT_HANDSHAKE && p[5] == SSL3_MT_SERVER_HELLO) ||
 534                   (p[0] == SSL3_RT_ALERT && p[3] == 0 && p[4] == 2)))
 535                 {
 536                 /* we have sslv3 or tls1 (server hello or alert) */
 537
 538 #ifndef OPENSSL_NO_SSL3
 539                 if ((p[2] == SSL3_VERSION_MINOR) &&
 540                         !(s->options & SSL_OP_NO_SSLv3))
 541                         {
 542 #ifdef OPENSSL_FIPS
 543                         if(FIPS_mode())
 544                                 {
 545                                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,
 546                                         SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
 547                                 goto err;
 548                                 }
 549 #endif
 550                         s->version=SSL3_VERSION;
 551                         s->method=SSLv3_client_method();
 552                         }
 553                 else
 554 #endif
 555                 if ((p[2] == TLS1_VERSION_MINOR) &&
 556                         !(s->options & SSL_OP_NO_TLSv1))
 557                         {
 558                         s->version=TLS1_VERSION;
 559                         s->method=TLSv1_client_method();
 560                         }
 561                 else
 562                         {
 563                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
 564                         goto err;
 565                         }
 566
 567                 /* ensure that TLS_MAX_VERSION is up-to-date */
 568                 OPENSSL_assert(s->version <= TLS_MAX_VERSION);
 569
 570                 if (p[0] == SSL3_RT_ALERT && p[5] != SSL3_AL_WARNING)
 571                         {
 572                         /* fatal alert */
 573
 574                         void (*cb)(const SSL *ssl,int type,int val)=NULL;
 575                         int j;
 576
 577                         if (s->info_callback != NULL)
 578                                 cb=s->info_callback;
 579                         else if (s->ctx->info_callback != NULL)
 580                                 cb=s->ctx->info_callback;
 581
 582                         i=p[5];
 583                         if (cb != NULL)
 584                                 {
 585                                 j=(i<<8)|p[6];
 586                                 cb(s,SSL_CB_READ_ALERT,j);
 587                                 }
 588
 589                         if (s->msg_callback)
 590                                 s->msg_callback(0, s->version, SSL3_RT_ALERT, p+5, 2, s, s->msg_callback_arg);
 591
 592                         s->rwstate=SSL_NOTHING;
 593                         SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_AD_REASON_OFFSET+p[6]);
 594                         goto err;
 595                         }
 596
 597                 if (!ssl_init_wbio_buffer(s,1)) goto err;
 598
 599                 /* we are in this state */
 600                 s->state=SSL3_ST_CR_SRVR_HELLO_A;
 601
 602                 /* put the 7 bytes we have read into the input buffer
 603                  * for SSLv3 */
 604                 s->rstate=SSL_ST_READ_HEADER;
 605                 s->packet_length=n;
 606                 if (s->s3->rbuf.buf == NULL)
 607                         if (!ssl3_setup_buffers(s))
 608                                 goto err;
 609                 s->packet= &(s->s3->rbuf.buf[0]);
 610                 memcpy(s->packet,buf,n);
 611                 s->s3->rbuf.left=n;
 612                 s->s3->rbuf.offset=0;
 613
 614                 s->handshake_func=s->method->ssl_connect;
 615                 }
 616         else
 617                 {
 618                 SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNKNOWN_PROTOCOL);
 619                 goto err;
 620                 }
 621         s->init_num=0;
 622
 623         /* Since, if we are sending a ssl23 client hello, we are not
 624          * reusing a session-id */
 625         if (!ssl_get_new_session(s,0))
 626                 goto err;
 627
 628         return(SSL_connect(s));
 629 err:
 630         return(-1);
 631         }
 632