s23_srvr.c revision 271305
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 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 135IMPLEMENT_ssl23_meth_func(SSLv23_server_method, 136 ssl23_accept, 137 ssl_undefined_function, 138 ssl23_get_server_method) 139 140int ssl23_accept(SSL *s) 141 { 142 BUF_MEM *buf; 143 unsigned long Time=(unsigned long)time(NULL); 144 void (*cb)(const SSL *ssl,int type,int val)=NULL; 145 int ret= -1; 146 int new_state,state; 147 148 RAND_add(&Time,sizeof(Time),0); 149 ERR_clear_error(); 150 clear_sys_error(); 151 152 if (s->info_callback != NULL) 153 cb=s->info_callback; 154 else if (s->ctx->info_callback != NULL) 155 cb=s->ctx->info_callback; 156 157 s->in_handshake++; 158 if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); 159 160 for (;;) 161 { 162 state=s->state; 163 164 switch(s->state) 165 { 166 case SSL_ST_BEFORE: 167 case SSL_ST_ACCEPT: 168 case SSL_ST_BEFORE|SSL_ST_ACCEPT: 169 case SSL_ST_OK|SSL_ST_ACCEPT: 170 171 s->server=1; 172 if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1); 173 174 /* s->version=SSL3_VERSION; */ 175 s->type=SSL_ST_ACCEPT; 176 177 if (s->init_buf == NULL) 178 { 179 if ((buf=BUF_MEM_new()) == NULL) 180 { 181 ret= -1; 182 goto end; 183 } 184 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH)) 185 { 186 ret= -1; 187 goto end; 188 } 189 s->init_buf=buf; 190 } 191 192 ssl3_init_finished_mac(s); 193 194 s->state=SSL23_ST_SR_CLNT_HELLO_A; 195 s->ctx->stats.sess_accept++; 196 s->init_num=0; 197 break; 198 199 case SSL23_ST_SR_CLNT_HELLO_A: 200 case SSL23_ST_SR_CLNT_HELLO_B: 201 202 s->shutdown=0; 203 ret=ssl23_get_client_hello(s); 204 if (ret >= 0) cb=NULL; 205 goto end; 206 /* break; */ 207 208 default: 209 SSLerr(SSL_F_SSL23_ACCEPT,SSL_R_UNKNOWN_STATE); 210 ret= -1; 211 goto end; 212 /* break; */ 213 } 214 215 if ((cb != NULL) && (s->state != state)) 216 { 217 new_state=s->state; 218 s->state=state; 219 cb(s,SSL_CB_ACCEPT_LOOP,1); 220 s->state=new_state; 221 } 222 } 223end: 224 s->in_handshake--; 225 if (cb != NULL) 226 cb(s,SSL_CB_ACCEPT_EXIT,ret); 227 return(ret); 228 } 229 230 231int ssl23_get_client_hello(SSL *s) 232 { 233 char buf_space[11]; /* Request this many bytes in initial read. 234 * We can detect SSL 3.0/TLS 1.0 Client Hellos 235 * ('type == 3') correctly only when the following 236 * is in a single record, which is not guaranteed by 237 * the protocol specification: 238 * Byte Content 239 * 0 type \ 240 * 1/2 version > record header 241 * 3/4 length / 242 * 5 msg_type \ 243 * 6-8 length > Client Hello message 244 * 9/10 client_version / 245 */ 246 char *buf= &(buf_space[0]); 247 unsigned char *p,*d,*d_len,*dd; 248 unsigned int i; 249 unsigned int csl,sil,cl; 250 int n=0,j; 251 int type=0; 252 int v[2]; 253 254 if (s->state == SSL23_ST_SR_CLNT_HELLO_A) 255 { 256 /* read the initial header */ 257 v[0]=v[1]=0; 258 259 if (!ssl3_setup_buffers(s)) goto err; 260 261 n=ssl23_read_bytes(s, sizeof buf_space); 262 if (n != sizeof buf_space) return(n); /* n == -1 || n == 0 */ 263 264 p=s->packet; 265 266 memcpy(buf,p,n); 267 268 if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO)) 269 { 270 /* 271 * SSLv2 header 272 */ 273 if ((p[3] == 0x00) && (p[4] == 0x02)) 274 { 275 v[0]=p[3]; v[1]=p[4]; 276 /* SSLv2 */ 277 if (!(s->options & SSL_OP_NO_SSLv2)) 278 type=1; 279 } 280 else if (p[3] == SSL3_VERSION_MAJOR) 281 { 282 v[0]=p[3]; v[1]=p[4]; 283 /* SSLv3/TLSv1 */ 284 if (p[4] >= TLS1_VERSION_MINOR) 285 { 286 if (!(s->options & SSL_OP_NO_TLSv1)) 287 { 288 s->version=TLS1_VERSION; 289 /* type=2; */ /* done later to survive restarts */ 290 s->state=SSL23_ST_SR_CLNT_HELLO_B; 291 } 292 else if (!(s->options & SSL_OP_NO_SSLv3)) 293 { 294 s->version=SSL3_VERSION; 295 /* type=2; */ 296 s->state=SSL23_ST_SR_CLNT_HELLO_B; 297 } 298 else if (!(s->options & SSL_OP_NO_SSLv2)) 299 { 300 type=1; 301 } 302 } 303 else if (!(s->options & SSL_OP_NO_SSLv3)) 304 { 305 s->version=SSL3_VERSION; 306 /* type=2; */ 307 s->state=SSL23_ST_SR_CLNT_HELLO_B; 308 } 309 else if (!(s->options & SSL_OP_NO_SSLv2)) 310 type=1; 311 312 } 313 } 314 else if ((p[0] == SSL3_RT_HANDSHAKE) && 315 (p[1] == SSL3_VERSION_MAJOR) && 316 (p[5] == SSL3_MT_CLIENT_HELLO) && 317 ((p[3] == 0 && p[4] < 5 /* silly record length? */) 318 || (p[9] >= p[1]))) 319 { 320 /* 321 * SSLv3 or tls1 header 322 */ 323 324 v[0]=p[1]; /* major version (= SSL3_VERSION_MAJOR) */ 325 /* We must look at client_version inside the Client Hello message 326 * to get the correct minor version. 327 * However if we have only a pathologically small fragment of the 328 * Client Hello message, this would be difficult, and we'd have 329 * to read more records to find out. 330 * No known SSL 3.0 client fragments ClientHello like this, 331 * so we simply reject such connections to avoid 332 * protocol version downgrade attacks. */ 333 if (p[3] == 0 && p[4] < 6) 334 { 335 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL); 336 goto err; 337 } 338 /* if major version number > 3 set minor to a value 339 * which will use the highest version 3 we support. 340 * If TLS 2.0 ever appears we will need to revise 341 * this.... 342 */ 343 if (p[9] > SSL3_VERSION_MAJOR) 344 v[1]=0xff; 345 else 346 v[1]=p[10]; /* minor version according to client_version */ 347 if (v[1] >= TLS1_VERSION_MINOR) 348 { 349 if (!(s->options & SSL_OP_NO_TLSv1)) 350 { 351 s->version=TLS1_VERSION; 352 type=3; 353 } 354 else if (!(s->options & SSL_OP_NO_SSLv3)) 355 { 356 s->version=SSL3_VERSION; 357 type=3; 358 } 359 } 360 else 361 { 362 /* client requests SSL 3.0 */ 363 if (!(s->options & SSL_OP_NO_SSLv3)) 364 { 365 s->version=SSL3_VERSION; 366 type=3; 367 } 368 else if (!(s->options & SSL_OP_NO_TLSv1)) 369 { 370 /* we won't be able to use TLS of course, 371 * but this will send an appropriate alert */ 372 s->version=TLS1_VERSION; 373 type=3; 374 } 375 } 376 } 377 else if ((strncmp("GET ", (char *)p,4) == 0) || 378 (strncmp("POST ",(char *)p,5) == 0) || 379 (strncmp("HEAD ",(char *)p,5) == 0) || 380 (strncmp("PUT ", (char *)p,4) == 0)) 381 { 382 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTP_REQUEST); 383 goto err; 384 } 385 else if (strncmp("CONNECT",(char *)p,7) == 0) 386 { 387 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTPS_PROXY_REQUEST); 388 goto err; 389 } 390 } 391 392#ifdef OPENSSL_FIPS 393 if (FIPS_mode() && (s->version < TLS1_VERSION)) 394 { 395 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO, 396 SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE); 397 goto err; 398 } 399#endif 400 401 if (s->state == SSL23_ST_SR_CLNT_HELLO_B) 402 { 403 /* we have SSLv3/TLSv1 in an SSLv2 header 404 * (other cases skip this state) */ 405 406 type=2; 407 p=s->packet; 408 v[0] = p[3]; /* == SSL3_VERSION_MAJOR */ 409 v[1] = p[4]; 410 411 /* An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2 412 * header is sent directly on the wire, not wrapped as a TLS 413 * record. It's format is: 414 * Byte Content 415 * 0-1 msg_length 416 * 2 msg_type 417 * 3-4 version 418 * 5-6 cipher_spec_length 419 * 7-8 session_id_length 420 * 9-10 challenge_length 421 * ... ... 422 */ 423 n=((p[0]&0x7f)<<8)|p[1]; 424 if (n > (1024*4)) 425 { 426 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE); 427 goto err; 428 } 429 if (n < 9) 430 { 431 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH); 432 goto err; 433 } 434 435 j=ssl23_read_bytes(s,n+2); 436 /* We previously read 11 bytes, so if j > 0, we must have 437 * j == n+2 == s->packet_length. We have at least 11 valid 438 * packet bytes. */ 439 if (j <= 0) return(j); 440 441 ssl3_finish_mac(s, s->packet+2, s->packet_length-2); 442 if (s->msg_callback) 443 s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */ 444 445 p=s->packet; 446 p+=5; 447 n2s(p,csl); 448 n2s(p,sil); 449 n2s(p,cl); 450 d=(unsigned char *)s->init_buf->data; 451 if ((csl+sil+cl+11) != s->packet_length) 452 { 453 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH); 454 goto err; 455 } 456 457 /* record header: msg_type ... */ 458 *(d++) = SSL3_MT_CLIENT_HELLO; 459 /* ... and length (actual value will be written later) */ 460 d_len = d; 461 d += 3; 462 463 /* client_version */ 464 *(d++) = SSL3_VERSION_MAJOR; /* == v[0] */ 465 *(d++) = v[1]; 466 467 /* lets populate the random area */ 468 /* get the challenge_length */ 469 i=(cl > SSL3_RANDOM_SIZE)?SSL3_RANDOM_SIZE:cl; 470 memset(d,0,SSL3_RANDOM_SIZE); 471 memcpy(&(d[SSL3_RANDOM_SIZE-i]),&(p[csl+sil]),i); 472 d+=SSL3_RANDOM_SIZE; 473 474 /* no session-id reuse */ 475 *(d++)=0; 476 477 /* ciphers */ 478 j=0; 479 dd=d; 480 d+=2; 481 for (i=0; i<csl; i+=3) 482 { 483 if (p[i] != 0) continue; 484 *(d++)=p[i+1]; 485 *(d++)=p[i+2]; 486 j+=2; 487 } 488 s2n(j,dd); 489 490 /* COMPRESSION */ 491 *(d++)=1; 492 *(d++)=0; 493 494 i = (d-(unsigned char *)s->init_buf->data) - 4; 495 l2n3((long)i, d_len); 496 497 /* get the data reused from the init_buf */ 498 s->s3->tmp.reuse_message=1; 499 s->s3->tmp.message_type=SSL3_MT_CLIENT_HELLO; 500 s->s3->tmp.message_size=i; 501 } 502 503 /* imaginary new state (for program structure): */ 504 /* s->state = SSL23_SR_CLNT_HELLO_C */ 505 506 if (type == 1) 507 { 508#ifdef OPENSSL_NO_SSL2 509 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL); 510 goto err; 511#else 512 /* we are talking sslv2 */ 513 /* we need to clean up the SSLv3/TLSv1 setup and put in the 514 * sslv2 stuff. */ 515 516 if (s->s2 == NULL) 517 { 518 if (!ssl2_new(s)) 519 goto err; 520 } 521 else 522 ssl2_clear(s); 523 524 if (s->s3 != NULL) ssl3_free(s); 525 526 if (!BUF_MEM_grow_clean(s->init_buf, 527 SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER)) 528 { 529 goto err; 530 } 531 532 s->state=SSL2_ST_GET_CLIENT_HELLO_A; 533 if (s->options & SSL_OP_NO_TLSv1 && s->options & SSL_OP_NO_SSLv3) 534 s->s2->ssl2_rollback=0; 535 else 536 /* reject SSL 2.0 session if client supports SSL 3.0 or TLS 1.0 537 * (SSL 3.0 draft/RFC 2246, App. E.2) */ 538 s->s2->ssl2_rollback=1; 539 540 /* setup the n bytes we have read so we get them from 541 * the sslv2 buffer */ 542 s->rstate=SSL_ST_READ_HEADER; 543 s->packet_length=n; 544 s->packet= &(s->s2->rbuf[0]); 545 memcpy(s->packet,buf,n); 546 s->s2->rbuf_left=n; 547 s->s2->rbuf_offs=0; 548 549 s->method=SSLv2_server_method(); 550 s->handshake_func=s->method->ssl_accept; 551#endif 552 } 553 554 if ((type == 2) || (type == 3)) 555 { 556 /* we have SSLv3/TLSv1 (type 2: SSL2 style, type 3: SSL3/TLS style) */ 557 558 if (!ssl_init_wbio_buffer(s,1)) goto err; 559 560 /* we are in this state */ 561 s->state=SSL3_ST_SR_CLNT_HELLO_A; 562 563 if (type == 3) 564 { 565 /* put the 'n' bytes we have read into the input buffer 566 * for SSLv3 */ 567 s->rstate=SSL_ST_READ_HEADER; 568 s->packet_length=n; 569 s->packet= &(s->s3->rbuf.buf[0]); 570 memcpy(s->packet,buf,n); 571 s->s3->rbuf.left=n; 572 s->s3->rbuf.offset=0; 573 } 574 else 575 { 576 s->packet_length=0; 577 s->s3->rbuf.left=0; 578 s->s3->rbuf.offset=0; 579 } 580 581 if (s->version == TLS1_VERSION) 582 s->method = TLSv1_server_method(); 583 else 584 s->method = SSLv3_server_method(); 585#if 0 /* ssl3_get_client_hello does this */ 586 s->client_version=(v[0]<<8)|v[1]; 587#endif 588 s->handshake_func=s->method->ssl_accept; 589 } 590 591 if ((type < 1) || (type > 3)) 592 { 593 /* bad, very bad */ 594 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNKNOWN_PROTOCOL); 595 goto err; 596 } 597 s->init_num=0; 598 599 if (buf != buf_space) OPENSSL_free(buf); 600 return(SSL_accept(s)); 601err: 602 if (buf != buf_space) OPENSSL_free(buf); 603 return(-1); 604 } 605