ssl/s2_srvr.c

   1 /* ssl/s2_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 #include "ssl_locl.h"
  60 #ifndef OPENSSL_NO_SSL2
  61 #include <stdio.h>
  62 #include <openssl/bio.h>
  63 #include <openssl/rand.h>
  64 #include <openssl/objects.h>
  65 #include <openssl/evp.h>
  66
  67 static SSL_METHOD *ssl2_get_server_method(int ver);
  68 static int get_client_master_key(SSL *s);
  69 static int get_client_hello(SSL *s);
  70 static int server_hello(SSL *s);
  71 static int get_client_finished(SSL *s);
  72 static int server_verify(SSL *s);
  73 static int server_finish(SSL *s);
  74 static int request_certificate(SSL *s);
  75 static int ssl_rsa_private_decrypt(CERT *c, int len, unsigned char *from,
  76         unsigned char *to,int padding);
  77 #define BREAK   break
  78
  79 static SSL_METHOD *ssl2_get_server_method(int ver)
  80         {
  81         if (ver == SSL2_VERSION)
  82                 return(SSLv2_server_method());
  83         else
  84                 return(NULL);
  85         }
  86
  87 SSL_METHOD *SSLv2_server_method(void)
  88         {
  89         static int init=1;
  90         static SSL_METHOD SSLv2_server_data;
  91
  92         if (init)
  93                 {
  94                 memcpy((char *)&SSLv2_server_data,(char *)sslv2_base_method(),
  95                         sizeof(SSL_METHOD));
  96                 SSLv2_server_data.ssl_accept=ssl2_accept;
  97                 SSLv2_server_data.get_ssl_method=ssl2_get_server_method;
  98                 init=0;
  99                 }
 100         return(&SSLv2_server_data);
 101         }
 102
 103 int ssl2_accept(SSL *s)
 104         {
 105         unsigned long l=time(NULL);
 106         BUF_MEM *buf=NULL;
 107         int ret= -1;
 108         long num1;
 109         void (*cb)()=NULL;
 110         int new_state,state;
 111
 112         RAND_add(&l,sizeof(l),0);
 113         ERR_clear_error();
 114         clear_sys_error();
 115
 116         if (s->info_callback != NULL)
 117                 cb=s->info_callback;
 118         else if (s->ctx->info_callback != NULL)
 119                 cb=s->ctx->info_callback;
 120
 121         /* init things to blank */
 122         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
 123         s->in_handshake++;
 124
 125         if (s->cert == NULL)
 126                 {
 127                 SSLerr(SSL_F_SSL2_ACCEPT,SSL_R_NO_CERTIFICATE_SET);
 128                 return(-1);
 129                 }
 130
 131         clear_sys_error();
 132         for (;;)
 133                 {
 134                 state=s->state;
 135
 136                 switch (s->state)
 137                         {
 138                 case SSL_ST_BEFORE:
 139                 case SSL_ST_ACCEPT:
 140                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
 141                 case SSL_ST_OK|SSL_ST_ACCEPT:
 142
 143                         s->server=1;
 144                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
 145
 146                         s->version=SSL2_VERSION;
 147                         s->type=SSL_ST_ACCEPT;
 148
 149                         buf=s->init_buf;
 150                         if ((buf == NULL) && ((buf=BUF_MEM_new()) == NULL))
 151                                 { ret= -1; goto end; }
 152                         if (!BUF_MEM_grow(buf,(int)
 153                                 SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
 154                                 { ret= -1; goto end; }
 155                         s->init_buf=buf;
 156                         s->init_num=0;
 157                         s->ctx->stats.sess_accept++;
 158                         s->handshake_func=ssl2_accept;
 159                         s->state=SSL2_ST_GET_CLIENT_HELLO_A;
 160                         BREAK;
 161
 162                 case SSL2_ST_GET_CLIENT_HELLO_A:
 163                 case SSL2_ST_GET_CLIENT_HELLO_B:
 164                 case SSL2_ST_GET_CLIENT_HELLO_C:
 165                         s->shutdown=0;
 166                         ret=get_client_hello(s);
 167                         if (ret <= 0) goto end;
 168                         s->init_num=0;
 169                         s->state=SSL2_ST_SEND_SERVER_HELLO_A;
 170                         BREAK;
 171
 172                 case SSL2_ST_SEND_SERVER_HELLO_A:
 173                 case SSL2_ST_SEND_SERVER_HELLO_B:
 174                         ret=server_hello(s);
 175                         if (ret <= 0) goto end;
 176                         s->init_num=0;
 177                         if (!s->hit)
 178                                 {
 179                                 s->state=SSL2_ST_GET_CLIENT_MASTER_KEY_A;
 180                                 BREAK;
 181                                 }
 182                         else
 183                                 {
 184                                 s->state=SSL2_ST_SERVER_START_ENCRYPTION;
 185                                 BREAK;
 186                                 }
 187                 case SSL2_ST_GET_CLIENT_MASTER_KEY_A:
 188                 case SSL2_ST_GET_CLIENT_MASTER_KEY_B:
 189                         ret=get_client_master_key(s);
 190                         if (ret <= 0) goto end;
 191                         s->init_num=0;
 192                         s->state=SSL2_ST_SERVER_START_ENCRYPTION;
 193                         BREAK;
 194
 195                 case SSL2_ST_SERVER_START_ENCRYPTION:
 196                         /* Ok we how have sent all the stuff needed to
 197                          * start encrypting, the next packet back will
 198                          * be encrypted. */
 199                         if (!ssl2_enc_init(s,0))
 200                                 { ret= -1; goto end; }
 201                         s->s2->clear_text=0;
 202                         s->state=SSL2_ST_SEND_SERVER_VERIFY_A;
 203                         BREAK;
 204
 205                 case SSL2_ST_SEND_SERVER_VERIFY_A:
 206                 case SSL2_ST_SEND_SERVER_VERIFY_B:
 207                         ret=server_verify(s);
 208                         if (ret <= 0) goto end;
 209                         s->init_num=0;
 210                         if (s->hit)
 211                                 {
 212                                 /* If we are in here, we have been
 213                                  * buffering the output, so we need to
 214                                  * flush it and remove buffering from
 215                                  * future traffic */
 216                                 s->state=SSL2_ST_SEND_SERVER_VERIFY_C;
 217                                 BREAK;
 218                                 }
 219                         else
 220                                 {
 221                                 s->state=SSL2_ST_GET_CLIENT_FINISHED_A;
 222                                 break;
 223                                 }
 224
 225                 case SSL2_ST_SEND_SERVER_VERIFY_C:
 226                         /* get the number of bytes to write */
 227                         num1=BIO_ctrl(s->wbio,BIO_CTRL_INFO,0,NULL);
 228                         if (num1 != 0)
 229                                 {
 230                                 s->rwstate=SSL_WRITING;
 231                                 num1=BIO_flush(s->wbio);
 232                                 if (num1 <= 0) { ret= -1; goto end; }
 233                                 s->rwstate=SSL_NOTHING;
 234                                 }
 235
 236                         /* flushed and now remove buffering */
 237                         s->wbio=BIO_pop(s->wbio);
 238
 239                         s->state=SSL2_ST_GET_CLIENT_FINISHED_A;
 240                         BREAK;
 241
 242                 case SSL2_ST_GET_CLIENT_FINISHED_A:
 243                 case SSL2_ST_GET_CLIENT_FINISHED_B:
 244                         ret=get_client_finished(s);
 245                         if (ret <= 0)
 246                                 goto end;
 247                         s->init_num=0;
 248                         s->state=SSL2_ST_SEND_REQUEST_CERTIFICATE_A;
 249                         BREAK;
 250
 251                 case SSL2_ST_SEND_REQUEST_CERTIFICATE_A:
 252                 case SSL2_ST_SEND_REQUEST_CERTIFICATE_B:
 253                 case SSL2_ST_SEND_REQUEST_CERTIFICATE_C:
 254                 case SSL2_ST_SEND_REQUEST_CERTIFICATE_D:
 255                         /* don't do a 'request certificate' if we
 256                          * don't want to, or we already have one, and
 257                          * we only want to do it once. */
 258                         if (!(s->verify_mode & SSL_VERIFY_PEER) ||
 259                                 ((s->session->peer != NULL) &&
 260                                 (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)))
 261                                 {
 262                                 s->state=SSL2_ST_SEND_SERVER_FINISHED_A;
 263                                 break;
 264                                 }
 265                         else
 266                                 {
 267                                 ret=request_certificate(s);
 268                                 if (ret <= 0) goto end;
 269                                 s->init_num=0;
 270                                 s->state=SSL2_ST_SEND_SERVER_FINISHED_A;
 271                                 }
 272                         BREAK;
 273
 274                 case SSL2_ST_SEND_SERVER_FINISHED_A:
 275                 case SSL2_ST_SEND_SERVER_FINISHED_B:
 276                         ret=server_finish(s);
 277                         if (ret <= 0) goto end;
 278                         s->init_num=0;
 279                         s->state=SSL_ST_OK;
 280                         break;
 281
 282                 case SSL_ST_OK:
 283                         BUF_MEM_free(s->init_buf);
 284                         ssl_free_wbio_buffer(s);
 285                         s->init_buf=NULL;
 286                         s->init_num=0;
 287                 /*      ERR_clear_error();*/
 288
 289                         ssl_update_cache(s,SSL_SESS_CACHE_SERVER);
 290
 291                         s->ctx->stats.sess_accept_good++;
 292                         /* s->server=1; */
 293                         ret=1;
 294
 295                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
 296
 297                         goto end;
 298                         /* BREAK; */
 299
 300                 default:
 301                         SSLerr(SSL_F_SSL2_ACCEPT,SSL_R_UNKNOWN_STATE);
 302                         ret= -1;
 303                         goto end;
 304                         /* BREAK; */
 305                         }
 306
 307                 if ((cb != NULL) && (s->state != state))
 308                         {
 309                         new_state=s->state;
 310                         s->state=state;
 311                         cb(s,SSL_CB_ACCEPT_LOOP,1);
 312                         s->state=new_state;
 313                         }
 314                 }
 315 end:
 316         s->in_handshake--;
 317         if (cb != NULL)
 318                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
 319         return(ret);
 320         }
 321
 322 static int get_client_master_key(SSL *s)
 323         {
 324         int is_export,i,n,keya,ek;
 325         unsigned char *p;
 326         SSL_CIPHER *cp;
 327         const EVP_CIPHER *c;
 328         const EVP_MD *md;
 329
 330         p=(unsigned char *)s->init_buf->data;
 331         if (s->state == SSL2_ST_GET_CLIENT_MASTER_KEY_A)
 332                 {
 333                 i=ssl2_read(s,(char *)&(p[s->init_num]),10-s->init_num);
 334
 335                 if (i < (10-s->init_num))
 336                         return(ssl2_part_read(s,SSL_F_GET_CLIENT_MASTER_KEY,i));
 337                 if (*(p++) != SSL2_MT_CLIENT_MASTER_KEY)
 338                         {
 339                         if (p[-1] != SSL2_MT_ERROR)
 340                                 {
 341                                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 342                                 SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,SSL_R_READ_WRONG_PACKET_TYPE);
 343                                 }
 344                         else
 345                                 SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,
 346                                         SSL_R_PEER_ERROR);
 347                         return(-1);
 348                         }
 349
 350                 cp=ssl2_get_cipher_by_char(p);
 351                 if (cp == NULL)
 352                         {
 353                         ssl2_return_error(s,SSL2_PE_NO_CIPHER);
 354                         SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,
 355                                 SSL_R_NO_CIPHER_MATCH);
 356                         return(-1);
 357                         }
 358                 s->session->cipher= cp;
 359
 360                 p+=3;
 361                 n2s(p,i); s->s2->tmp.clear=i;
 362                 n2s(p,i); s->s2->tmp.enc=i;
 363                 n2s(p,i); s->session->key_arg_length=i;
 364                 s->state=SSL2_ST_GET_CLIENT_MASTER_KEY_B;
 365                 s->init_num=0;
 366                 }
 367
 368         /* SSL2_ST_GET_CLIENT_MASTER_KEY_B */
 369         p=(unsigned char *)s->init_buf->data;
 370         keya=s->session->key_arg_length;
 371         n=s->s2->tmp.clear+s->s2->tmp.enc+keya - s->init_num;
 372         i=ssl2_read(s,(char *)&(p[s->init_num]),n);
 373         if (i != n) return(ssl2_part_read(s,SSL_F_GET_CLIENT_MASTER_KEY,i));
 374
 375         memcpy(s->session->key_arg,&(p[s->s2->tmp.clear+s->s2->tmp.enc]),
 376                 (unsigned int)keya);
 377
 378         if (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL)
 379                 {
 380                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 381                 SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,SSL_R_NO_PRIVATEKEY);
 382                 return(-1);
 383                 }
 384         i=ssl_rsa_private_decrypt(s->cert,s->s2->tmp.enc,
 385                 &(p[s->s2->tmp.clear]),&(p[s->s2->tmp.clear]),
 386                 (s->s2->ssl2_rollback)?RSA_SSLV23_PADDING:RSA_PKCS1_PADDING);
 387
 388         is_export=SSL_C_IS_EXPORT(s->session->cipher);
 389
 390         if (!ssl_cipher_get_evp(s->session,&c,&md,NULL))
 391                 {
 392                 ssl2_return_error(s,SSL2_PE_NO_CIPHER);
 393                 SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS);
 394                 return(0);
 395                 }
 396
 397         if (s->session->cipher->algorithm2 & SSL2_CF_8_BYTE_ENC)
 398                 {
 399                 is_export=1;
 400                 ek=8;
 401                 }
 402         else
 403                 ek=5;
 404
 405         /* bad decrypt */
 406 #if 1
 407         /* If a bad decrypt, continue with protocol but with a
 408          * dud master secret */
 409         if ((i < 0) ||
 410                 ((!is_export && (i != EVP_CIPHER_key_length(c)))
 411                 || (is_export && ((i != ek) || (s->s2->tmp.clear+i !=
 412                         EVP_CIPHER_key_length(c))))))
 413                 {
 414                 if (is_export)
 415                         i=ek;
 416                 else
 417                         i=EVP_CIPHER_key_length(c);
 418                 RAND_pseudo_bytes(p,i);
 419                 }
 420 #else
 421         if (i < 0)
 422                 {
 423                 error=1;
 424                 SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,SSL_R_BAD_RSA_DECRYPT);
 425                 }
 426         /* incorrect number of key bytes for non export cipher */
 427         else if ((!is_export && (i != EVP_CIPHER_key_length(c)))
 428                 || (is_export && ((i != ek) || (s->s2->tmp.clear+i !=
 429                         EVP_CIPHER_key_length(c)))))
 430                 {
 431                 error=1;
 432                 SSLerr(SSL_F_GET_CLIENT_MASTER_KEY,SSL_R_WRONG_NUMBER_OF_KEY_BITS);
 433                 }
 434         if (error)
 435                 {
 436                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 437                 return(-1);
 438                 }
 439 #endif
 440
 441         if (is_export) i+=s->s2->tmp.clear;
 442         s->session->master_key_length=i;
 443         memcpy(s->session->master_key,p,(unsigned int)i);
 444         return(1);
 445         }
 446
 447 static int get_client_hello(SSL *s)
 448         {
 449         int i,n;
 450         unsigned char *p;
 451         STACK_OF(SSL_CIPHER) *cs; /* a stack of SSL_CIPHERS */
 452         STACK_OF(SSL_CIPHER) *cl; /* the ones we want to use */
 453         STACK_OF(SSL_CIPHER) *prio, *allow;
 454         int z;
 455
 456         /* This is a bit of a hack to check for the correct packet
 457          * type the first time round. */
 458         if (s->state == SSL2_ST_GET_CLIENT_HELLO_A)
 459                 {
 460                 s->first_packet=1;
 461                 s->state=SSL2_ST_GET_CLIENT_HELLO_B;
 462                 }
 463
 464         p=(unsigned char *)s->init_buf->data;
 465         if (s->state == SSL2_ST_GET_CLIENT_HELLO_B)
 466                 {
 467                 i=ssl2_read(s,(char *)&(p[s->init_num]),9-s->init_num);
 468                 if (i < (9-s->init_num))
 469                         return(ssl2_part_read(s,SSL_F_GET_CLIENT_HELLO,i));
 470
 471                 if (*(p++) != SSL2_MT_CLIENT_HELLO)
 472                         {
 473                         if (p[-1] != SSL2_MT_ERROR)
 474                                 {
 475                                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 476                                 SSLerr(SSL_F_GET_CLIENT_HELLO,SSL_R_READ_WRONG_PACKET_TYPE);
 477                                 }
 478                         else
 479                                 SSLerr(SSL_F_GET_CLIENT_HELLO,SSL_R_PEER_ERROR);
 480                         return(-1);
 481                         }
 482                 n2s(p,i);
 483                 if (i < s->version) s->version=i;
 484                 n2s(p,i); s->s2->tmp.cipher_spec_length=i;
 485                 n2s(p,i); s->s2->tmp.session_id_length=i;
 486                 n2s(p,i); s->s2->challenge_length=i;
 487                 if (    (i < SSL2_MIN_CHALLENGE_LENGTH) ||
 488                         (i > SSL2_MAX_CHALLENGE_LENGTH))
 489                         {
 490                         SSLerr(SSL_F_GET_CLIENT_HELLO,SSL_R_INVALID_CHALLENGE_LENGTH);
 491                         return(-1);
 492                         }
 493                 s->state=SSL2_ST_GET_CLIENT_HELLO_C;
 494                 s->init_num=0;
 495                 }
 496
 497         /* SSL2_ST_GET_CLIENT_HELLO_C */
 498         p=(unsigned char *)s->init_buf->data;
 499         n=s->s2->tmp.cipher_spec_length+s->s2->challenge_length+
 500                 s->s2->tmp.session_id_length-s->init_num;
 501         i=ssl2_read(s,(char *)&(p[s->init_num]),n);
 502         if (i != n) return(ssl2_part_read(s,SSL_F_GET_CLIENT_HELLO,i));
 503
 504         /* get session-id before cipher stuff so we can get out session
 505          * structure if it is cached */
 506         /* session-id */
 507         if ((s->s2->tmp.session_id_length != 0) &&
 508                 (s->s2->tmp.session_id_length != SSL2_SSL_SESSION_ID_LENGTH))
 509                 {
 510                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 511                 SSLerr(SSL_F_GET_CLIENT_HELLO,SSL_R_BAD_SSL_SESSION_ID_LENGTH);
 512                 return(-1);
 513                 }
 514
 515         if (s->s2->tmp.session_id_length == 0)
 516                 {
 517                 if (!ssl_get_new_session(s,1))
 518                         {
 519                         ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 520                         return(-1);
 521                         }
 522                 }
 523         else
 524                 {
 525                 i=ssl_get_prev_session(s,&(p[s->s2->tmp.cipher_spec_length]),
 526                         s->s2->tmp.session_id_length);
 527                 if (i == 1)
 528                         { /* previous session */
 529                         s->hit=1;
 530                         }
 531                 else if (i == -1)
 532                         {
 533                         ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 534                         return(-1);
 535                         }
 536                 else
 537                         {
 538                         if (s->cert == NULL)
 539                                 {
 540                                 ssl2_return_error(s,SSL2_PE_NO_CERTIFICATE);
 541                                 SSLerr(SSL_F_GET_CLIENT_HELLO,SSL_R_NO_CERTIFICATE_SET);
 542                                 return(-1);
 543                                 }
 544
 545                         if (!ssl_get_new_session(s,1))
 546                                 {
 547                                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 548                                 return(-1);
 549                                 }
 550                         }
 551                 }
 552
 553         if (!s->hit)
 554                 {
 555                 cs=ssl_bytes_to_cipher_list(s,p,s->s2->tmp.cipher_spec_length,
 556                         &s->session->ciphers);
 557                 if (cs == NULL) goto mem_err;
 558
 559                 cl=SSL_get_ciphers(s);
 560
 561                 if (s->options & SSL_OP_CIPHER_SERVER_PREFERENCE)
 562                     {
 563                     prio=sk_SSL_CIPHER_dup(cl);
 564                     if (prio == NULL) goto mem_err;
 565                     allow = cs;
 566                     }
 567                 else
 568                     {
 569                     prio = cs;
 570                     allow = cl;
 571                     }
 572                 for (z=0; z<sk_SSL_CIPHER_num(prio); z++)
 573                         {
 574                         if (sk_SSL_CIPHER_find(allow,sk_SSL_CIPHER_value(prio,z)) < 0)
 575                                 {
 576                                 sk_SSL_CIPHER_delete(prio,z);
 577                                 z--;
 578                                 }
 579                         }
 580                 if (s->options & SSL_OP_CIPHER_SERVER_PREFERENCE)
 581                     {
 582                     sk_SSL_CIPHER_free(s->session->ciphers);
 583                     s->session->ciphers = prio;
 584                     }
 585                 /* s->session->ciphers should now have a list of
 586                  * ciphers that are on both the client and server.
 587                  * This list is ordered by the order the client sent
 588                  * the ciphers or in the order of the server's preference
 589                  * if SSL_OP_CIPHER_SERVER_PREFERENCE was set.
 590                  */
 591                 }
 592         p+=s->s2->tmp.cipher_spec_length;
 593         /* done cipher selection */
 594
 595         /* session id extracted already */
 596         p+=s->s2->tmp.session_id_length;
 597
 598         /* challenge */
 599         memcpy(s->s2->challenge,p,(unsigned int)s->s2->challenge_length);
 600         return(1);
 601 mem_err:
 602         SSLerr(SSL_F_GET_CLIENT_HELLO,ERR_R_MALLOC_FAILURE);
 603         return(0);
 604         }
 605
 606 static int server_hello(SSL *s)
 607         {
 608         unsigned char *p,*d;
 609         int n,hit;
 610         STACK_OF(SSL_CIPHER) *sk;
 611
 612         p=(unsigned char *)s->init_buf->data;
 613         if (s->state == SSL2_ST_SEND_SERVER_HELLO_A)
 614                 {
 615                 d=p+11;
 616                 *(p++)=SSL2_MT_SERVER_HELLO;            /* type */
 617                 hit=s->hit;
 618                 *(p++)=(unsigned char)hit;
 619 #if 1
 620                 if (!hit)
 621                         {
 622                         if (s->session->sess_cert != NULL)
 623                                 /* This can't really happen because get_client_hello
 624                                  * has called ssl_get_new_session, which does not set
 625                                  * sess_cert. */
 626                                 ssl_sess_cert_free(s->session->sess_cert);
 627                         s->session->sess_cert = ssl_sess_cert_new();
 628                         if (s->session->sess_cert == NULL)
 629                                 {
 630                                 SSLerr(SSL_F_SERVER_HELLO, ERR_R_MALLOC_FAILURE);
 631                                 return(-1);
 632                                 }
 633                         }
 634                 /* If 'hit' is set, then s->sess_cert may be non-NULL or NULL,
 635                  * depending on whether it survived in the internal cache
 636                  * or was retrieved from an external cache.
 637                  * If it is NULL, we cannot put any useful data in it anyway,
 638                  * so we don't touch it.
 639                  */
 640
 641 #else /* That's what used to be done when cert_st and sess_cert_st were
 642            * the same. */
 643                 if (!hit)
 644                         {                       /* else add cert to session */
 645                         CRYPTO_add(&s->cert->references,1,CRYPTO_LOCK_SSL_CERT);
 646                         if (s->session->sess_cert != NULL)
 647                                 ssl_cert_free(s->session->sess_cert);
 648                         s->session->sess_cert=s->cert;
 649                         }
 650                 else    /* We have a session id-cache hit, if the
 651                          * session-id has no certificate listed against
 652                          * the 'cert' structure, grab the 'old' one
 653                          * listed against the SSL connection */
 654                         {
 655                         if (s->session->sess_cert == NULL)
 656                                 {
 657                                 CRYPTO_add(&s->cert->references,1,
 658                                         CRYPTO_LOCK_SSL_CERT);
 659                                 s->session->sess_cert=s->cert;
 660                                 }
 661                         }
 662 #endif
 663
 664                 if (s->cert == NULL)
 665                         {
 666                         ssl2_return_error(s,SSL2_PE_NO_CERTIFICATE);
 667                         SSLerr(SSL_F_SERVER_HELLO,SSL_R_NO_CERTIFICATE_SPECIFIED);
 668                         return(-1);
 669                         }
 670
 671                 if (hit)
 672                         {
 673                         *(p++)=0;               /* no certificate type */
 674                         s2n(s->version,p);      /* version */
 675                         s2n(0,p);               /* cert len */
 676                         s2n(0,p);               /* ciphers len */
 677                         }
 678                 else
 679                         {
 680                         /* EAY EAY */
 681                         /* put certificate type */
 682                         *(p++)=SSL2_CT_X509_CERTIFICATE;
 683                         s2n(s->version,p);      /* version */
 684                         n=i2d_X509(s->cert->pkeys[SSL_PKEY_RSA_ENC].x509,NULL);
 685                         s2n(n,p);               /* certificate length */
 686                         i2d_X509(s->cert->pkeys[SSL_PKEY_RSA_ENC].x509,&d);
 687                         n=0;
 688
 689                         /* lets send out the ciphers we like in the
 690                          * prefered order */
 691                         sk= s->session->ciphers;
 692                         n=ssl_cipher_list_to_bytes(s,s->session->ciphers,d);
 693                         d+=n;
 694                         s2n(n,p);               /* add cipher length */
 695                         }
 696
 697                 /* make and send conn_id */
 698                 s2n(SSL2_CONNECTION_ID_LENGTH,p);       /* add conn_id length */
 699                 s->s2->conn_id_length=SSL2_CONNECTION_ID_LENGTH;
 700                 RAND_pseudo_bytes(s->s2->conn_id,(int)s->s2->conn_id_length);
 701                 memcpy(d,s->s2->conn_id,SSL2_CONNECTION_ID_LENGTH);
 702                 d+=SSL2_CONNECTION_ID_LENGTH;
 703
 704                 s->state=SSL2_ST_SEND_SERVER_HELLO_B;
 705                 s->init_num=d-(unsigned char *)s->init_buf->data;
 706                 s->init_off=0;
 707                 }
 708         /* SSL2_ST_SEND_SERVER_HELLO_B */
 709         /* If we are using TCP/IP, the performance is bad if we do 2
 710          * writes without a read between them.  This occurs when
 711          * Session-id reuse is used, so I will put in a buffering module
 712          */
 713         if (s->hit)
 714                 {
 715                 if (!ssl_init_wbio_buffer(s,1)) return(-1);
 716                 }
 717
 718         return(ssl2_do_write(s));
 719         }
 720
 721 static int get_client_finished(SSL *s)
 722         {
 723         unsigned char *p;
 724         int i;
 725
 726         p=(unsigned char *)s->init_buf->data;
 727         if (s->state == SSL2_ST_GET_CLIENT_FINISHED_A)
 728                 {
 729                 i=ssl2_read(s,(char *)&(p[s->init_num]),1-s->init_num);
 730                 if (i < 1-s->init_num)
 731                         return(ssl2_part_read(s,SSL_F_GET_CLIENT_FINISHED,i));
 732
 733                 if (*p != SSL2_MT_CLIENT_FINISHED)
 734                         {
 735                         if (*p != SSL2_MT_ERROR)
 736                                 {
 737                                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 738                                 SSLerr(SSL_F_GET_CLIENT_FINISHED,SSL_R_READ_WRONG_PACKET_TYPE);
 739                                 }
 740                         else
 741                                 SSLerr(SSL_F_GET_CLIENT_FINISHED,SSL_R_PEER_ERROR);
 742                         return(-1);
 743                         }
 744                 s->init_num=0;
 745                 s->state=SSL2_ST_GET_CLIENT_FINISHED_B;
 746                 }
 747
 748         /* SSL2_ST_GET_CLIENT_FINISHED_B */
 749         i=ssl2_read(s,(char *)&(p[s->init_num]),s->s2->conn_id_length-s->init_num);
 750         if (i < (int)s->s2->conn_id_length-s->init_num)
 751                 {
 752                 return(ssl2_part_read(s,SSL_F_GET_CLIENT_FINISHED,i));
 753                 }
 754         if (memcmp(p,s->s2->conn_id,(unsigned int)s->s2->conn_id_length) != 0)
 755                 {
 756                 ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 757                 SSLerr(SSL_F_GET_CLIENT_FINISHED,SSL_R_CONNECTION_ID_IS_DIFFERENT);
 758                 return(-1);
 759                 }
 760         return(1);
 761         }
 762
 763 static int server_verify(SSL *s)
 764         {
 765         unsigned char *p;
 766
 767         if (s->state == SSL2_ST_SEND_SERVER_VERIFY_A)
 768                 {
 769                 p=(unsigned char *)s->init_buf->data;
 770                 *(p++)=SSL2_MT_SERVER_VERIFY;
 771                 memcpy(p,s->s2->challenge,(unsigned int)s->s2->challenge_length);
 772                 /* p+=s->s2->challenge_length; */
 773
 774                 s->state=SSL2_ST_SEND_SERVER_VERIFY_B;
 775                 s->init_num=s->s2->challenge_length+1;
 776                 s->init_off=0;
 777                 }
 778         return(ssl2_do_write(s));
 779         }
 780
 781 static int server_finish(SSL *s)
 782         {
 783         unsigned char *p;
 784
 785         if (s->state == SSL2_ST_SEND_SERVER_FINISHED_A)
 786                 {
 787                 p=(unsigned char *)s->init_buf->data;
 788                 *(p++)=SSL2_MT_SERVER_FINISHED;
 789
 790                 memcpy(p,s->session->session_id,
 791                         (unsigned int)s->session->session_id_length);
 792                 /* p+=s->session->session_id_length; */
 793
 794                 s->state=SSL2_ST_SEND_SERVER_FINISHED_B;
 795                 s->init_num=s->session->session_id_length+1;
 796                 s->init_off=0;
 797                 }
 798
 799         /* SSL2_ST_SEND_SERVER_FINISHED_B */
 800         return(ssl2_do_write(s));
 801         }
 802
 803 /* send the request and check the response */
 804 static int request_certificate(SSL *s)
 805         {
 806         unsigned char *p,*p2,*buf2;
 807         unsigned char *ccd;
 808         int i,j,ctype,ret= -1;
 809         X509 *x509=NULL;
 810         STACK_OF(X509) *sk=NULL;
 811
 812         ccd=s->s2->tmp.ccl;
 813         if (s->state == SSL2_ST_SEND_REQUEST_CERTIFICATE_A)
 814                 {
 815                 p=(unsigned char *)s->init_buf->data;
 816                 *(p++)=SSL2_MT_REQUEST_CERTIFICATE;
 817                 *(p++)=SSL2_AT_MD5_WITH_RSA_ENCRYPTION;
 818                 RAND_pseudo_bytes(ccd,SSL2_MIN_CERT_CHALLENGE_LENGTH);
 819                 memcpy(p,ccd,SSL2_MIN_CERT_CHALLENGE_LENGTH);
 820
 821                 s->state=SSL2_ST_SEND_REQUEST_CERTIFICATE_B;
 822                 s->init_num=SSL2_MIN_CERT_CHALLENGE_LENGTH+2;
 823                 s->init_off=0;
 824                 }
 825
 826         if (s->state == SSL2_ST_SEND_REQUEST_CERTIFICATE_B)
 827                 {
 828                 i=ssl2_do_write(s);
 829                 if (i <= 0)
 830                         {
 831                         ret=i;
 832                         goto end;
 833                         }
 834
 835                 s->init_num=0;
 836                 s->state=SSL2_ST_SEND_REQUEST_CERTIFICATE_C;
 837                 }
 838
 839         if (s->state == SSL2_ST_SEND_REQUEST_CERTIFICATE_C)
 840                 {
 841                 p=(unsigned char *)s->init_buf->data;
 842                 i=ssl2_read(s,(char *)&(p[s->init_num]),6-s->init_num);
 843                 if (i < 3)
 844                         {
 845                         ret=ssl2_part_read(s,SSL_F_REQUEST_CERTIFICATE,i);
 846                         goto end;
 847                         }
 848
 849                 if ((*p == SSL2_MT_ERROR) && (i >= 3))
 850                         {
 851                         n2s(p,i);
 852                         if (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)
 853                                 {
 854                                 ssl2_return_error(s,SSL2_PE_BAD_CERTIFICATE);
 855                                 SSLerr(SSL_F_REQUEST_CERTIFICATE,SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
 856                                 goto end;
 857                                 }
 858                         ret=1;
 859                         goto end;
 860                         }
 861                 if ((*(p++) != SSL2_MT_CLIENT_CERTIFICATE) || (i < 6))
 862                         {
 863                         ssl2_return_error(s,SSL2_PE_UNDEFINED_ERROR);
 864                         SSLerr(SSL_F_REQUEST_CERTIFICATE,SSL_R_SHORT_READ);
 865                         goto end;
 866                         }
 867                 /* ok we have a response */
 868                 /* certificate type, there is only one right now. */
 869                 ctype= *(p++);
 870                 if (ctype != SSL2_AT_MD5_WITH_RSA_ENCRYPTION)
 871                         {
 872                         ssl2_return_error(s,SSL2_PE_UNSUPPORTED_CERTIFICATE_TYPE);
 873                         SSLerr(SSL_F_REQUEST_CERTIFICATE,SSL_R_BAD_RESPONSE_ARGUMENT);
 874                         goto end;
 875                         }
 876                 n2s(p,i); s->s2->tmp.clen=i;
 877                 n2s(p,i); s->s2->tmp.rlen=i;
 878                 s->state=SSL2_ST_SEND_REQUEST_CERTIFICATE_D;
 879                 s->init_num=0;
 880                 }
 881
 882         /* SSL2_ST_SEND_REQUEST_CERTIFICATE_D */
 883         p=(unsigned char *)s->init_buf->data;
 884         j=s->s2->tmp.clen+s->s2->tmp.rlen-s->init_num;
 885         i=ssl2_read(s,(char *)&(p[s->init_num]),j);
 886         if (i < j)
 887                 {
 888                 ret=ssl2_part_read(s,SSL_F_REQUEST_CERTIFICATE,i);
 889                 goto end;
 890                 }
 891
 892         x509=(X509 *)d2i_X509(NULL,&p,(long)s->s2->tmp.clen);
 893         if (x509 == NULL)
 894                 {
 895                 SSLerr(SSL_F_REQUEST_CERTIFICATE,ERR_R_X509_LIB);
 896                 goto msg_end;
 897                 }
 898
 899         if (((sk=sk_X509_new_null()) == NULL) || (!sk_X509_push(sk,x509)))
 900                 {
 901                 SSLerr(SSL_F_REQUEST_CERTIFICATE,ERR_R_MALLOC_FAILURE);
 902                 goto msg_end;
 903                 }
 904
 905         i=ssl_verify_cert_chain(s,sk);
 906
 907         if (i)  /* we like the packet, now check the chksum */
 908                 {
 909                 EVP_MD_CTX ctx;
 910                 EVP_PKEY *pkey=NULL;
 911
 912                 EVP_VerifyInit(&ctx,s->ctx->rsa_md5);
 913                 EVP_VerifyUpdate(&ctx,s->s2->key_material,
 914                         (unsigned int)s->s2->key_material_length);
 915                 EVP_VerifyUpdate(&ctx,ccd,SSL2_MIN_CERT_CHALLENGE_LENGTH);
 916
 917                 i=i2d_X509(s->cert->pkeys[SSL_PKEY_RSA_ENC].x509,NULL);
 918                 buf2=OPENSSL_malloc((unsigned int)i);
 919                 if (buf2 == NULL)
 920                         {
 921                         SSLerr(SSL_F_REQUEST_CERTIFICATE,ERR_R_MALLOC_FAILURE);
 922                         goto msg_end;
 923                         }
 924                 p2=buf2;
 925                 i=i2d_X509(s->cert->pkeys[SSL_PKEY_RSA_ENC].x509,&p2);
 926                 EVP_VerifyUpdate(&ctx,buf2,(unsigned int)i);
 927                 OPENSSL_free(buf2);
 928
 929                 pkey=X509_get_pubkey(x509);
 930                 if (pkey == NULL) goto end;
 931                 i=EVP_VerifyFinal(&ctx,p,s->s2->tmp.rlen,pkey);
 932                 EVP_PKEY_free(pkey);
 933                 memset(&ctx,0,sizeof(ctx));
 934
 935                 if (i)
 936                         {
 937                         if (s->session->peer != NULL)
 938                                 X509_free(s->session->peer);
 939                         s->session->peer=x509;
 940                         CRYPTO_add(&x509->references,1,CRYPTO_LOCK_X509);
 941                         s->session->verify_result = s->verify_result;
 942                         ret=1;
 943                         goto end;
 944                         }
 945                 else
 946                         {
 947                         SSLerr(SSL_F_REQUEST_CERTIFICATE,SSL_R_BAD_CHECKSUM);
 948                         goto msg_end;
 949                         }
 950                 }
 951         else
 952                 {
 953 msg_end:
 954                 ssl2_return_error(s,SSL2_PE_BAD_CERTIFICATE);
 955                 }
 956 end:
 957         sk_X509_free(sk);
 958         X509_free(x509);
 959         return(ret);
 960         }
 961
 962 static int ssl_rsa_private_decrypt(CERT *c, int len, unsigned char *from,
 963              unsigned char *to, int padding)
 964         {
 965         RSA *rsa;
 966         int i;
 967
 968         if ((c == NULL) || (c->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL))
 969                 {
 970                 SSLerr(SSL_F_SSL_RSA_PRIVATE_DECRYPT,SSL_R_NO_PRIVATEKEY);
 971                 return(-1);
 972                 }
 973         if (c->pkeys[SSL_PKEY_RSA_ENC].privatekey->type != EVP_PKEY_RSA)
 974                 {
 975                 SSLerr(SSL_F_SSL_RSA_PRIVATE_DECRYPT,SSL_R_PUBLIC_KEY_IS_NOT_RSA);
 976                 return(-1);
 977                 }
 978         rsa=c->pkeys[SSL_PKEY_RSA_ENC].privatekey->pkey.rsa;
 979
 980         /* we have the public key */
 981         i=RSA_private_decrypt(len,from,to,rsa,padding);
 982         if (i < 0)
 983                 SSLerr(SSL_F_SSL_RSA_PRIVATE_DECRYPT,ERR_R_RSA_LIB);
 984         return(i);
 985         }
 986 #else /* !OPENSSL_NO_SSL2 */
 987
 988 # if PEDANTIC
 989 static void *dummy=&dummy;
 990 # endif
 991
 992 #endif