s23_srvr.c revision 277195
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 119static SSL_METHOD *ssl23_get_server_method(int ver); 120int ssl23_get_client_hello(SSL *s); 121static 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#ifndef OPENSSL_NO_SSL3 128 if (ver == SSL3_VERSION) 129 return(SSLv3_server_method()); 130#endif 131 if (ver == TLS1_VERSION) 132 return(TLSv1_server_method()); 133 else 134 return(NULL); 135 } 136 137IMPLEMENT_ssl23_meth_func(SSLv23_server_method, 138 ssl23_accept, 139 ssl_undefined_function, 140 ssl23_get_server_method) 141 142int ssl23_accept(SSL *s) 143 { 144 BUF_MEM *buf; 145 unsigned long Time=(unsigned long)time(NULL); 146 void (*cb)(const SSL *ssl,int type,int val)=NULL; 147 int ret= -1; 148 int new_state,state; 149 150 RAND_add(&Time,sizeof(Time),0); 151 ERR_clear_error(); 152 clear_sys_error(); 153 154 if (s->info_callback != NULL) 155 cb=s->info_callback; 156 else if (s->ctx->info_callback != NULL) 157 cb=s->ctx->info_callback; 158 159 s->in_handshake++; 160 if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); 161 162 for (;;) 163 { 164 state=s->state; 165 166 switch(s->state) 167 { 168 case SSL_ST_BEFORE: 169 case SSL_ST_ACCEPT: 170 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 171 case SSL_ST_OK|SSL_ST_ACCEPT: 172 173 s->server=1; 174 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1); 175 176 /* s->version=SSL3_VERSION; */ 177 s->type=SSL_ST_ACCEPT; 178 179 if (s->init_buf == NULL) 180 { 181 if ((buf=BUF_MEM_new()) == NULL) 182 { 183 ret= -1; 184 goto end; 185 } 186 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH)) 187 { 188 ret= -1; 189 goto end; 190 } 191 s->init_buf=buf; 192 } 193 194 ssl3_init_finished_mac(s); 195 196 s->state=SSL23_ST_SR_CLNT_HELLO_A; 197 s->ctx->stats.sess_accept++; 198 s->init_num=0; 199 break; 200 201 case SSL23_ST_SR_CLNT_HELLO_A: 202 case SSL23_ST_SR_CLNT_HELLO_B: 203 204 s->shutdown=0; 205 ret=ssl23_get_client_hello(s); 206 if (ret >= 0) cb=NULL; 207 goto end; 208 /* break; */ 209 210 default: 211 SSLerr(SSL_F_SSL23_ACCEPT,SSL_R_UNKNOWN_STATE); 212 ret= -1; 213 goto end; 214 /* break; */ 215 } 216 217 if ((cb != NULL) && (s->state != state)) 218 { 219 new_state=s->state; 220 s->state=state; 221 cb(s,SSL_CB_ACCEPT_LOOP,1); 222 s->state=new_state; 223 } 224 } 225end: 226 s->in_handshake--; 227 if (cb != NULL) 228 cb(s,SSL_CB_ACCEPT_EXIT,ret); 229 return(ret); 230 } 231 232 233int ssl23_get_client_hello(SSL *s) 234 { 235 char buf_space[11]; /* Request this many bytes in initial read. 236 * We can detect SSL 3.0/TLS 1.0 Client Hellos 237 * ('type == 3') correctly only when the following 238 * is in a single record, which is not guaranteed by 239 * the protocol specification: 240 * Byte Content 241 * 0 type \ 242 * 1/2 version > record header 243 * 3/4 length / 244 * 5 msg_type \ 245 * 6-8 length > Client Hello message 246 * 9/10 client_version / 247 */ 248 char *buf= &(buf_space[0]); 249 unsigned char *p,*d,*d_len,*dd; 250 unsigned int i; 251 unsigned int csl,sil,cl; 252 int n=0,j; 253 int type=0; 254 int v[2]; 255 256 if (s->state == SSL23_ST_SR_CLNT_HELLO_A) 257 { 258 /* read the initial header */ 259 v[0]=v[1]=0; 260 261 if (!ssl3_setup_buffers(s)) goto err; 262 263 n=ssl23_read_bytes(s, sizeof buf_space); 264 if (n != sizeof buf_space) return(n); /* n == -1 || n == 0 */ 265 266 p=s->packet; 267 268 memcpy(buf,p,n); 269 270 if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO)) 271 { 272 /* 273 * SSLv2 header 274 */ 275 if ((p[3] == 0x00) && (p[4] == 0x02)) 276 { 277 v[0]=p[3]; v[1]=p[4]; 278 /* SSLv2 */ 279 if (!(s->options & SSL_OP_NO_SSLv2)) 280 type=1; 281 } 282 else if (p[3] == SSL3_VERSION_MAJOR) 283 { 284 v[0]=p[3]; v[1]=p[4]; 285 /* SSLv3/TLSv1 */ 286 if (p[4] >= TLS1_VERSION_MINOR) 287 { 288 if (!(s->options & SSL_OP_NO_TLSv1)) 289 { 290 s->version=TLS1_VERSION; 291 /* type=2; */ /* done later to survive restarts */ 292 s->state=SSL23_ST_SR_CLNT_HELLO_B; 293 } 294 else if (!(s->options & SSL_OP_NO_SSLv3)) 295 { 296 s->version=SSL3_VERSION; 297 /* type=2; */ 298 s->state=SSL23_ST_SR_CLNT_HELLO_B; 299 } 300 else if (!(s->options & SSL_OP_NO_SSLv2)) 301 { 302 type=1; 303 } 304 } 305 else if (!(s->options & SSL_OP_NO_SSLv3)) 306 { 307 s->version=SSL3_VERSION; 308 /* type=2; */ 309 s->state=SSL23_ST_SR_CLNT_HELLO_B; 310 } 311 else if (!(s->options & SSL_OP_NO_SSLv2)) 312 type=1; 313 314 } 315 } 316 else if ((p[0] == SSL3_RT_HANDSHAKE) && 317 (p[1] == SSL3_VERSION_MAJOR) && 318 (p[5] == SSL3_MT_CLIENT_HELLO) && 319 ((p[3] == 0 && p[4] < 5 /* silly record length? */) 320 || (p[9] >= p[1]))) 321 { 322 /* 323 * SSLv3 or tls1 header 324 */ 325 326 v[0]=p[1]; /* major version (= SSL3_VERSION_MAJOR) */ 327 /* We must look at client_version inside the Client Hello message 328 * to get the correct minor version. 329 * However if we have only a pathologically small fragment of the 330 * Client Hello message, this would be difficult, and we'd have 331 * to read more records to find out. 332 * No known SSL 3.0 client fragments ClientHello like this, 333 * so we simply reject such connections to avoid 334 * protocol version downgrade attacks. */ 335 if (p[3] == 0 && p[4] < 6) 336 { 337 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL); 338 goto err; 339 } 340 /* if major version number > 3 set minor to a value 341 * which will use the highest version 3 we support. 342 * If TLS 2.0 ever appears we will need to revise 343 * this.... 344 */ 345 if (p[9] > SSL3_VERSION_MAJOR) 346 v[1]=0xff; 347 else 348 v[1]=p[10]; /* minor version according to client_version */ 349 if (v[1] >= TLS1_VERSION_MINOR) 350 { 351 if (!(s->options & SSL_OP_NO_TLSv1)) 352 { 353 s->version=TLS1_VERSION; 354 type=3; 355 } 356 else if (!(s->options & SSL_OP_NO_SSLv3)) 357 { 358 s->version=SSL3_VERSION; 359 type=3; 360 } 361 } 362 else 363 { 364 /* client requests SSL 3.0 */ 365 if (!(s->options & SSL_OP_NO_SSLv3)) 366 { 367 s->version=SSL3_VERSION; 368 type=3; 369 } 370 else if (!(s->options & SSL_OP_NO_TLSv1)) 371 { 372 /* we won't be able to use TLS of course, 373 * but this will send an appropriate alert */ 374 s->version=TLS1_VERSION; 375 type=3; 376 } 377 } 378 } 379 else if ((strncmp("GET ", (char *)p,4) == 0) || 380 (strncmp("POST ",(char *)p,5) == 0) || 381 (strncmp("HEAD ",(char *)p,5) == 0) || 382 (strncmp("PUT ", (char *)p,4) == 0)) 383 { 384 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTP_REQUEST); 385 goto err; 386 } 387 else if (strncmp("CONNECT",(char *)p,7) == 0) 388 { 389 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTPS_PROXY_REQUEST); 390 goto err; 391 } 392 } 393 394#ifdef OPENSSL_FIPS 395 if (FIPS_mode() && (s->version < TLS1_VERSION)) 396 { 397 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO, 398 SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE); 399 goto err; 400 } 401#endif 402 403 /* ensure that TLS_MAX_VERSION is up-to-date */ 404 OPENSSL_assert(s->version <= TLS_MAX_VERSION); 405 406 if (s->state == SSL23_ST_SR_CLNT_HELLO_B) 407 { 408 /* we have SSLv3/TLSv1 in an SSLv2 header 409 * (other cases skip this state) */ 410 411 type=2; 412 p=s->packet; 413 v[0] = p[3]; /* == SSL3_VERSION_MAJOR */ 414 v[1] = p[4]; 415 416 /* An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2 417 * header is sent directly on the wire, not wrapped as a TLS 418 * record. It's format is: 419 * Byte Content 420 * 0-1 msg_length 421 * 2 msg_type 422 * 3-4 version 423 * 5-6 cipher_spec_length 424 * 7-8 session_id_length 425 * 9-10 challenge_length 426 * ... ... 427 */ 428 n=((p[0]&0x7f)<<8)|p[1]; 429 if (n > (1024*4)) 430 { 431 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE); 432 goto err; 433 } 434 if (n < 9) 435 { 436 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH); 437 goto err; 438 } 439 440 j=ssl23_read_bytes(s,n+2); 441 /* We previously read 11 bytes, so if j > 0, we must have 442 * j == n+2 == s->packet_length. We have at least 11 valid 443 * packet bytes. */ 444 if (j <= 0) return(j); 445 446 ssl3_finish_mac(s, s->packet+2, s->packet_length-2); 447 if (s->msg_callback) 448 s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */ 449 450 p=s->packet; 451 p+=5; 452 n2s(p,csl); 453 n2s(p,sil); 454 n2s(p,cl); 455 d=(unsigned char *)s->init_buf->data; 456 if ((csl+sil+cl+11) != s->packet_length) 457 { 458 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH); 459 goto err; 460 } 461 462 /* record header: msg_type ... */ 463 *(d++) = SSL3_MT_CLIENT_HELLO; 464 /* ... and length (actual value will be written later) */ 465 d_len = d; 466 d += 3; 467 468 /* client_version */ 469 *(d++) = SSL3_VERSION_MAJOR; /* == v[0] */ 470 *(d++) = v[1]; 471 472 /* lets populate the random area */ 473 /* get the challenge_length */ 474 i=(cl > SSL3_RANDOM_SIZE)?SSL3_RANDOM_SIZE:cl; 475 memset(d,0,SSL3_RANDOM_SIZE); 476 memcpy(&(d[SSL3_RANDOM_SIZE-i]),&(p[csl+sil]),i); 477 d+=SSL3_RANDOM_SIZE; 478 479 /* no session-id reuse */ 480 *(d++)=0; 481 482 /* ciphers */ 483 j=0; 484 dd=d; 485 d+=2; 486 for (i=0; i<csl; i+=3) 487 { 488 if (p[i] != 0) continue; 489 *(d++)=p[i+1]; 490 *(d++)=p[i+2]; 491 j+=2; 492 } 493 s2n(j,dd); 494 495 /* COMPRESSION */ 496 *(d++)=1; 497 *(d++)=0; 498 499 i = (d-(unsigned char *)s->init_buf->data) - 4; 500 l2n3((long)i, d_len); 501 502 /* get the data reused from the init_buf */ 503 s->s3->tmp.reuse_message=1; 504 s->s3->tmp.message_type=SSL3_MT_CLIENT_HELLO; 505 s->s3->tmp.message_size=i; 506 } 507 508 /* imaginary new state (for program structure): */ 509 /* s->state = SSL23_SR_CLNT_HELLO_C */ 510 511 if (type == 1) 512 { 513#ifdef OPENSSL_NO_SSL2 514 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL); 515 goto err; 516#else 517 /* we are talking sslv2 */ 518 /* we need to clean up the SSLv3/TLSv1 setup and put in the 519 * sslv2 stuff. */ 520 521 if (s->s2 == NULL) 522 { 523 if (!ssl2_new(s)) 524 goto err; 525 } 526 else 527 ssl2_clear(s); 528 529 if (s->s3 != NULL) ssl3_free(s); 530 531 if (!BUF_MEM_grow_clean(s->init_buf, 532 SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER)) 533 { 534 goto err; 535 } 536 537 s->state=SSL2_ST_GET_CLIENT_HELLO_A; 538 if (s->options & SSL_OP_NO_TLSv1 && s->options & SSL_OP_NO_SSLv3) 539 s->s2->ssl2_rollback=0; 540 else 541 /* reject SSL 2.0 session if client supports SSL 3.0 or TLS 1.0 542 * (SSL 3.0 draft/RFC 2246, App. E.2) */ 543 s->s2->ssl2_rollback=1; 544 545 /* setup the n bytes we have read so we get them from 546 * the sslv2 buffer */ 547 s->rstate=SSL_ST_READ_HEADER; 548 s->packet_length=n; 549 s->packet= &(s->s2->rbuf[0]); 550 memcpy(s->packet,buf,n); 551 s->s2->rbuf_left=n; 552 s->s2->rbuf_offs=0; 553 554 s->method=SSLv2_server_method(); 555 s->handshake_func=s->method->ssl_accept; 556#endif 557 } 558 559 if ((type == 2) || (type == 3)) 560 { 561 /* we have SSLv3/TLSv1 (type 2: SSL2 style, type 3: SSL3/TLS style) */ 562 SSL_METHOD *new_method; 563 new_method = ssl23_get_server_method(s->version); 564 if (new_method == NULL) 565 { 566 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL); 567 goto err; 568 } 569 s->method = new_method; 570 571 if (!ssl_init_wbio_buffer(s,1)) goto err; 572 573 /* we are in this state */ 574 s->state=SSL3_ST_SR_CLNT_HELLO_A; 575 576 if (type == 3) 577 { 578 /* put the 'n' bytes we have read into the input buffer 579 * for SSLv3 */ 580 s->rstate=SSL_ST_READ_HEADER; 581 s->packet_length=n; 582 s->packet= &(s->s3->rbuf.buf[0]); 583 memcpy(s->packet,buf,n); 584 s->s3->rbuf.left=n; 585 s->s3->rbuf.offset=0; 586 } 587 else 588 { 589 s->packet_length=0; 590 s->s3->rbuf.left=0; 591 s->s3->rbuf.offset=0; 592 } 593#if 0 /* ssl3_get_client_hello does this */ 594 s->client_version=(v[0]<<8)|v[1]; 595#endif 596 s->handshake_func=s->method->ssl_accept; 597 } 598 599 if ((type < 1) || (type > 3)) 600 { 601 /* bad, very bad */ 602 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNKNOWN_PROTOCOL); 603 goto err; 604 } 605 s->init_num=0; 606 607 if (buf != buf_space) OPENSSL_free(buf); 608 return(SSL_accept(s)); 609err: 610 if (buf != buf_space) OPENSSL_free(buf); 611 return(-1); 612 } 613