1 /* ssl/s23_srvr.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 /* ==================================================================== 59 * Copyright (c) 1998-2001 The OpenSSL Project. All rights reserved. 60 * 61 * Redistribution and use in source and binary forms, with or without 62 * modification, are permitted provided that the following conditions 63 * are met: 64 * 65 * 1. Redistributions of source code must retain the above copyright 66 * notice, this list of conditions and the following disclaimer. 67 * 68 * 2. Redistributions in binary form must reproduce the above copyright 69 * notice, this list of conditions and the following disclaimer in 70 * the documentation and/or other materials provided with the 71 * distribution. 72 * 73 * 3. All advertising materials mentioning features or use of this 74 * software must display the following acknowledgment: 75 * "This product includes software developed by the OpenSSL Project 76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 77 * 78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 79 * endorse or promote products derived from this software without 80 * prior written permission. For written permission, please contact 81 * openssl-core@openssl.org. 82 * 83 * 5. Products derived from this software may not be called "OpenSSL" 84 * nor may "OpenSSL" appear in their names without prior written 85 * permission of the OpenSSL Project. 86 * 87 * 6. Redistributions of any form whatsoever must retain the following 88 * acknowledgment: 89 * "This product includes software developed by the OpenSSL Project 90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 91 * 92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 103 * OF THE POSSIBILITY OF SUCH DAMAGE. 104 * ==================================================================== 105 * 106 * This product includes cryptographic software written by Eric Young 107 * (eay@cryptsoft.com). This product includes software written by Tim 108 * Hudson (tjh@cryptsoft.com). 109 * 110 */ 111 112 #include <stdio.h> 113 #include "ssl_locl.h" 114 #include <openssl/buffer.h> 115 #include <openssl/rand.h> 116 #include <openssl/objects.h> 117 #include <openssl/evp.h> 118 119 static SSL_METHOD *ssl23_get_server_method(int ver); 120 int ssl23_get_client_hello(SSL *s); 121 static SSL_METHOD *ssl23_get_server_method(int ver) 122 { 123 #ifndef OPENSSL_NO_SSL2 124 if (ver == SSL2_VERSION) 125 return(SSLv2_server_method()); 126 #endif 127 if (ver == SSL3_VERSION) 128 return(SSLv3_server_method()); 129 else if (ver == TLS1_VERSION) 130 return(TLSv1_server_method()); 131 else 132 return(NULL); 133 } 134 135 SSL_METHOD *SSLv23_server_method(void) 136 { 137 static int init=1; 138 static SSL_METHOD SSLv23_server_data; 139 140 if (init) 141 { 142 CRYPTO_w_lock(CRYPTO_LOCK_SSL_METHOD); 143 144 if (init) 145 { 146 memcpy((char *)&SSLv23_server_data, 147 (char *)sslv23_base_method(),sizeof(SSL_METHOD)); 148 SSLv23_server_data.ssl_accept=ssl23_accept; 149 SSLv23_server_data.get_ssl_method=ssl23_get_server_method; 150 init=0; 151 } 152 153 CRYPTO_w_unlock(CRYPTO_LOCK_SSL_METHOD); 154 } 155 return(&SSLv23_server_data); 156 } 157 158 int ssl23_accept(SSL *s) 159 { 160 BUF_MEM *buf; 161 unsigned long Time=time(NULL); 162 void (*cb)(const SSL *ssl,int type,int val)=NULL; 163 int ret= -1; 164 int new_state,state; 165 166 RAND_add(&Time,sizeof(Time),0); 167 ERR_clear_error(); 168 clear_sys_error(); 169 170 if (s->info_callback != NULL) 171 cb=s->info_callback; 172 else if (s->ctx->info_callback != NULL) 173 cb=s->ctx->info_callback; 174 175 s->in_handshake++; 176 if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); 177 178 for (;;) 179 { 180 state=s->state; 181 182 switch(s->state) 183 { 184 case SSL_ST_BEFORE: 185 case SSL_ST_ACCEPT: 186 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 187 case SSL_ST_OK|SSL_ST_ACCEPT: 188 189 s->server=1; 190 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1); 191 192 /* s->version=SSL3_VERSION; */ 193 s->type=SSL_ST_ACCEPT; 194 195 if (s->init_buf == NULL) 196 { 197 if ((buf=BUF_MEM_new()) == NULL) 198 { 199 ret= -1; 200 goto end; 201 } 202 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH)) 203 { 204 ret= -1; 205 goto end; 206 } 207 s->init_buf=buf; 208 } 209 210 ssl3_init_finished_mac(s); 211 212 s->state=SSL23_ST_SR_CLNT_HELLO_A; 213 s->ctx->stats.sess_accept++; 214 s->init_num=0; 215 break; 216 217 case SSL23_ST_SR_CLNT_HELLO_A: 218 case SSL23_ST_SR_CLNT_HELLO_B: 219 220 s->shutdown=0; 221 ret=ssl23_get_client_hello(s); 222 if (ret >= 0) cb=NULL; 223 goto end; 224 /* break; */ 225 226 default: 227 SSLerr(SSL_F_SSL23_ACCEPT,SSL_R_UNKNOWN_STATE); 228 ret= -1; 229 goto end; 230 /* break; */ 231 } 232 233 if ((cb != NULL) && (s->state != state)) 234 { 235 new_state=s->state; 236 s->state=state; 237 cb(s,SSL_CB_ACCEPT_LOOP,1); 238 s->state=new_state; 239 } 240 } 241 end: 242 s->in_handshake--; 243 if (cb != NULL) 244 cb(s,SSL_CB_ACCEPT_EXIT,ret); 245 return(ret); 246 } 247 248 249 int ssl23_get_client_hello(SSL *s) 250 { 251 char buf_space[11]; /* Request this many bytes in initial read. 252 * We can detect SSL 3.0/TLS 1.0 Client Hellos 253 * ('type == 3') correctly only when the following 254 * is in a single record, which is not guaranteed by 255 * the protocol specification: 256 * Byte Content 257 * 0 type \ 258 * 1/2 version > record header 259 * 3/4 length / 260 * 5 msg_type \ 261 * 6-8 length > Client Hello message 262 * 9/10 client_version / 263 */ 264 char *buf= &(buf_space[0]); 265 unsigned char *p,*d,*d_len,*dd; 266 unsigned int i; 267 unsigned int csl,sil,cl; 268 int n=0,j; 269 int type=0; 270 int v[2]; 271 272 if (s->state == SSL23_ST_SR_CLNT_HELLO_A) 273 { 274 /* read the initial header */ 275 v[0]=v[1]=0; 276 277 if (!ssl3_setup_buffers(s)) goto err; 278 279 n=ssl23_read_bytes(s, sizeof buf_space); 280 if (n != sizeof buf_space) return(n); /* n == -1 || n == 0 */ 281 282 p=s->packet; 283 284 memcpy(buf,p,n); 285 286 if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO)) 287 { 288 /* 289 * SSLv2 header 290 */ 291 if ((p[3] == 0x00) && (p[4] == 0x02)) 292 { 293 v[0]=p[3]; v[1]=p[4]; 294 /* SSLv2 */ 295 if (!(s->options & SSL_OP_NO_SSLv2)) 296 type=1; 297 } 298 else if (p[3] == SSL3_VERSION_MAJOR) 299 { 300 v[0]=p[3]; v[1]=p[4]; 301 /* SSLv3/TLSv1 */ 302 if (p[4] >= TLS1_VERSION_MINOR) 303 { 304 if (!(s->options & SSL_OP_NO_TLSv1)) 305 { 306 s->version=TLS1_VERSION; 307 /* type=2; */ /* done later to survive restarts */ 308 s->state=SSL23_ST_SR_CLNT_HELLO_B; 309 } 310 else if (!(s->options & SSL_OP_NO_SSLv3)) 311 { 312 s->version=SSL3_VERSION; 313 /* type=2; */ 314 s->state=SSL23_ST_SR_CLNT_HELLO_B; 315 } 316 else if (!(s->options & SSL_OP_NO_SSLv2)) 317 { 318 type=1; 319 } 320 } 321 else if (!(s->options & SSL_OP_NO_SSLv3)) 322 { 323 s->version=SSL3_VERSION; 324 /* type=2; */ 325 s->state=SSL23_ST_SR_CLNT_HELLO_B; 326 } 327 else if (!(s->options & SSL_OP_NO_SSLv2)) 328 type=1; 329 330 } 331 } 332 else if ((p[0] == SSL3_RT_HANDSHAKE) && 333 (p[1] == SSL3_VERSION_MAJOR) && 334 (p[5] == SSL3_MT_CLIENT_HELLO) && 335 ((p[3] == 0 && p[4] < 5 /* silly record length? */) 336 || (p[9] == p[1]))) 337 { 338 /* 339 * SSLv3 or tls1 header 340 */ 341 342 v[0]=p[1]; /* major version (= SSL3_VERSION_MAJOR) */ 343 /* We must look at client_version inside the Client Hello message 344 * to get the correct minor version. 345 * However if we have only a pathologically small fragment of the 346 * Client Hello message, this would be difficult, and we'd have 347 * to read more records to find out. 348 * No known SSL 3.0 client fragments ClientHello like this, 349 * so we simply assume TLS 1.0 to avoid protocol version downgrade 350 * attacks. */ 351 if (p[3] == 0 && p[4] < 6) 352 { 353 #if 0 354 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL); 355 goto err; 356 #else 357 v[1] = TLS1_VERSION_MINOR; 358 #endif 359 } 360 else 361 v[1]=p[10]; /* minor version according to client_version */ 362 if (v[1] >= TLS1_VERSION_MINOR) 363 { 364 if (!(s->options & SSL_OP_NO_TLSv1)) 365 { 366 s->version=TLS1_VERSION; 367 type=3; 368 } 369 else if (!(s->options & SSL_OP_NO_SSLv3)) 370 { 371 s->version=SSL3_VERSION; 372 type=3; 373 } 374 } 375 else 376 { 377 /* client requests SSL 3.0 */ 378 if (!(s->options & SSL_OP_NO_SSLv3)) 379 { 380 s->version=SSL3_VERSION; 381 type=3; 382 } 383 else if (!(s->options & SSL_OP_NO_TLSv1)) 384 { 385 /* we won't be able to use TLS of course, 386 * but this will send an appropriate alert */ 387 s->version=TLS1_VERSION; 388 type=3; 389 } 390 } 391 } 392 else if ((strncmp("GET ", (char *)p,4) == 0) || 393 (strncmp("POST ",(char *)p,5) == 0) || 394 (strncmp("HEAD ",(char *)p,5) == 0) || 395 (strncmp("PUT ", (char *)p,4) == 0)) 396 { 397 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTP_REQUEST); 398 goto err; 399 } 400 else if (strncmp("CONNECT",(char *)p,7) == 0) 401 { 402 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTPS_PROXY_REQUEST); 403 goto err; 404 } 405 } 406 407 if (s->state == SSL23_ST_SR_CLNT_HELLO_B) 408 { 409 /* we have SSLv3/TLSv1 in an SSLv2 header 410 * (other cases skip this state) */ 411 412 type=2; 413 p=s->packet; 414 v[0] = p[3]; /* == SSL3_VERSION_MAJOR */ 415 v[1] = p[4]; 416 417 n=((p[0]&0x7f)<<8)|p[1]; 418 if (n > (1024*4)) 419 { 420 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE); 421 goto err; 422 } 423 424 j=ssl23_read_bytes(s,n+2); 425 if (j <= 0) return(j); 426 427 ssl3_finish_mac(s, s->packet+2, s->packet_length-2); 428 if (s->msg_callback) 429 s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */ 430 431 p=s->packet; 432 p+=5; 433 n2s(p,csl); 434 n2s(p,sil); 435 n2s(p,cl); 436 d=(unsigned char *)s->init_buf->data; 437 if ((csl+sil+cl+11) != s->packet_length) 438 { 439 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH); 440 goto err; 441 } 442 443 /* record header: msg_type ... */ 444 *(d++) = SSL3_MT_CLIENT_HELLO; 445 /* ... and length (actual value will be written later) */ 446 d_len = d; 447 d += 3; 448 449 /* client_version */ 450 *(d++) = SSL3_VERSION_MAJOR; /* == v[0] */ 451 *(d++) = v[1]; 452 453 /* lets populate the random area */ 454 /* get the challenge_length */ 455 i=(cl > SSL3_RANDOM_SIZE)?SSL3_RANDOM_SIZE:cl; 456 memset(d,0,SSL3_RANDOM_SIZE); 457 memcpy(&(d[SSL3_RANDOM_SIZE-i]),&(p[csl+sil]),i); 458 d+=SSL3_RANDOM_SIZE; 459 460 /* no session-id reuse */ 461 *(d++)=0; 462 463 /* ciphers */ 464 j=0; 465 dd=d; 466 d+=2; 467 for (i=0; i<csl; i+=3) 468 { 469 if (p[i] != 0) continue; 470 *(d++)=p[i+1]; 471 *(d++)=p[i+2]; 472 j+=2; 473 } 474 s2n(j,dd); 475 476 /* COMPRESSION */ 477 *(d++)=1; 478 *(d++)=0; 479 480 i = (d-(unsigned char *)s->init_buf->data) - 4; 481 l2n3((long)i, d_len); 482 483 /* get the data reused from the init_buf */ 484 s->s3->tmp.reuse_message=1; 485 s->s3->tmp.message_type=SSL3_MT_CLIENT_HELLO; 486 s->s3->tmp.message_size=i; 487 } 488 489 /* imaginary new state (for program structure): */ 490 /* s->state = SSL23_SR_CLNT_HELLO_C */ 491 492 if (type == 1) 493 { 494 #ifdef OPENSSL_NO_SSL2 495 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL); 496 goto err; 497 #else 498 /* we are talking sslv2 */ 499 /* we need to clean up the SSLv3/TLSv1 setup and put in the 500 * sslv2 stuff. */ 501 502 if (s->s2 == NULL) 503 { 504 if (!ssl2_new(s)) 505 goto err; 506 } 507 else 508 ssl2_clear(s); 509 510 if (s->s3 != NULL) ssl3_free(s); 511 512 if (!BUF_MEM_grow_clean(s->init_buf, 513 SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER)) 514 { 515 goto err; 516 } 517 518 s->state=SSL2_ST_GET_CLIENT_HELLO_A; 519 if (s->options & SSL_OP_NO_TLSv1 && s->options & SSL_OP_NO_SSLv3) 520 s->s2->ssl2_rollback=0; 521 else 522 /* reject SSL 2.0 session if client supports SSL 3.0 or TLS 1.0 523 * (SSL 3.0 draft/RFC 2246, App. E.2) */ 524 s->s2->ssl2_rollback=1; 525 526 /* setup the n bytes we have read so we get them from 527 * the sslv2 buffer */ 528 s->rstate=SSL_ST_READ_HEADER; 529 s->packet_length=n; 530 s->packet= &(s->s2->rbuf[0]); 531 memcpy(s->packet,buf,n); 532 s->s2->rbuf_left=n; 533 s->s2->rbuf_offs=0; 534 535 s->method=SSLv2_server_method(); 536 s->handshake_func=s->method->ssl_accept; 537 #endif 538 } 539 540 if ((type == 2) || (type == 3)) 541 { 542 /* we have SSLv3/TLSv1 (type 2: SSL2 style, type 3: SSL3/TLS style) */ 543 544 if (!ssl_init_wbio_buffer(s,1)) goto err; 545 546 /* we are in this state */ 547 s->state=SSL3_ST_SR_CLNT_HELLO_A; 548 549 if (type == 3) 550 { 551 /* put the 'n' bytes we have read into the input buffer 552 * for SSLv3 */ 553 s->rstate=SSL_ST_READ_HEADER; 554 s->packet_length=n; 555 s->packet= &(s->s3->rbuf.buf[0]); 556 memcpy(s->packet,buf,n); 557 s->s3->rbuf.left=n; 558 s->s3->rbuf.offset=0; 559 } 560 else 561 { 562 s->packet_length=0; 563 s->s3->rbuf.left=0; 564 s->s3->rbuf.offset=0; 565 } 566 567 if (s->version == TLS1_VERSION) 568 s->method = TLSv1_server_method(); 569 else 570 s->method = SSLv3_server_method(); 571 #if 0 /* ssl3_get_client_hello does this */ 572 s->client_version=(v[0]<<8)|v[1]; 573 #endif 574 s->handshake_func=s->method->ssl_accept; 575 } 576 577 if ((type < 1) || (type > 3)) 578 { 579 /* bad, very bad */ 580 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNKNOWN_PROTOCOL); 581 goto err; 582 } 583 s->init_num=0; 584 585 if (buf != buf_space) OPENSSL_free(buf); 586 s->first_packet=1; 587 return(SSL_accept(s)); 588 err: 589 if (buf != buf_space) OPENSSL_free(buf); 590 return(-1); 591 } 592