• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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);
ssl23_get_server_method(int ver)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 
IMPLEMENT_ssl23_meth_func(SSLv23_server_method,ssl23_accept,ssl_undefined_function,ssl23_get_server_method)135 IMPLEMENT_ssl23_meth_func(SSLv23_server_method,
136 			ssl23_accept,
137 			ssl_undefined_function,
138 			ssl23_get_server_method)
139 
140 int 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 		}
223 end:
224 	s->in_handshake--;
225 	if (cb != NULL)
226 		cb(s,SSL_CB_ACCEPT_EXIT,ret);
227 	return(ret);
228 	}
229 
230 
ssl23_get_client_hello(SSL * s)231 int 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 assume TLS 1.0 to avoid protocol version downgrade
332 			 * attacks. */
333 			if (p[3] == 0 && p[4] < 6)
334 				{
335 #if 0
336 				SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL);
337 				goto err;
338 #else
339 				v[1] = TLS1_VERSION_MINOR;
340 #endif
341 				}
342 			else
343 				v[1]=p[10]; /* minor version according to client_version */
344 			if (v[1] >= TLS1_VERSION_MINOR)
345 				{
346 				if (!(s->options & SSL_OP_NO_TLSv1))
347 					{
348 					s->version=TLS1_VERSION;
349 					type=3;
350 					}
351 				else if (!(s->options & SSL_OP_NO_SSLv3))
352 					{
353 					s->version=SSL3_VERSION;
354 					type=3;
355 					}
356 				}
357 			else
358 				{
359 				/* client requests SSL 3.0 */
360 				if (!(s->options & SSL_OP_NO_SSLv3))
361 					{
362 					s->version=SSL3_VERSION;
363 					type=3;
364 					}
365 				else if (!(s->options & SSL_OP_NO_TLSv1))
366 					{
367 					/* we won't be able to use TLS of course,
368 					 * but this will send an appropriate alert */
369 					s->version=TLS1_VERSION;
370 					type=3;
371 					}
372 				}
373 			}
374 		else if ((strncmp("GET ", (char *)p,4) == 0) ||
375 			 (strncmp("POST ",(char *)p,5) == 0) ||
376 			 (strncmp("HEAD ",(char *)p,5) == 0) ||
377 			 (strncmp("PUT ", (char *)p,4) == 0))
378 			{
379 			SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTP_REQUEST);
380 			goto err;
381 			}
382 		else if (strncmp("CONNECT",(char *)p,7) == 0)
383 			{
384 			SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTPS_PROXY_REQUEST);
385 			goto err;
386 			}
387 		}
388 
389 	if (s->state == SSL23_ST_SR_CLNT_HELLO_B)
390 		{
391 		/* we have SSLv3/TLSv1 in an SSLv2 header
392 		 * (other cases skip this state) */
393 
394 		type=2;
395 		p=s->packet;
396 		v[0] = p[3]; /* == SSL3_VERSION_MAJOR */
397 		v[1] = p[4];
398 
399 		n=((p[0]&0x7f)<<8)|p[1];
400 		if (n > (1024*4))
401 			{
402 			SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE);
403 			goto err;
404 			}
405 
406 		j=ssl23_read_bytes(s,n+2);
407 		if (j <= 0) return(j);
408 
409 		ssl3_finish_mac(s, s->packet+2, s->packet_length-2);
410 		if (s->msg_callback)
411 			s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */
412 
413 		p=s->packet;
414 		p+=5;
415 		n2s(p,csl);
416 		n2s(p,sil);
417 		n2s(p,cl);
418 		d=(unsigned char *)s->init_buf->data;
419 		if ((csl+sil+cl+11) != s->packet_length)
420 			{
421 			SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH);
422 			goto err;
423 			}
424 
425 		/* record header: msg_type ... */
426 		*(d++) = SSL3_MT_CLIENT_HELLO;
427 		/* ... and length (actual value will be written later) */
428 		d_len = d;
429 		d += 3;
430 
431 		/* client_version */
432 		*(d++) = SSL3_VERSION_MAJOR; /* == v[0] */
433 		*(d++) = v[1];
434 
435 		/* lets populate the random area */
436 		/* get the challenge_length */
437 		i=(cl > SSL3_RANDOM_SIZE)?SSL3_RANDOM_SIZE:cl;
438 		memset(d,0,SSL3_RANDOM_SIZE);
439 		memcpy(&(d[SSL3_RANDOM_SIZE-i]),&(p[csl+sil]),i);
440 		d+=SSL3_RANDOM_SIZE;
441 
442 		/* no session-id reuse */
443 		*(d++)=0;
444 
445 		/* ciphers */
446 		j=0;
447 		dd=d;
448 		d+=2;
449 		for (i=0; i<csl; i+=3)
450 			{
451 			if (p[i] != 0) continue;
452 			*(d++)=p[i+1];
453 			*(d++)=p[i+2];
454 			j+=2;
455 			}
456 		s2n(j,dd);
457 
458 		/* COMPRESSION */
459 		*(d++)=1;
460 		*(d++)=0;
461 
462 		i = (d-(unsigned char *)s->init_buf->data) - 4;
463 		l2n3((long)i, d_len);
464 
465 		/* get the data reused from the init_buf */
466 		s->s3->tmp.reuse_message=1;
467 		s->s3->tmp.message_type=SSL3_MT_CLIENT_HELLO;
468 		s->s3->tmp.message_size=i;
469 		}
470 
471 	/* imaginary new state (for program structure): */
472 	/* s->state = SSL23_SR_CLNT_HELLO_C */
473 
474 	if (type == 1)
475 		{
476 #ifdef OPENSSL_NO_SSL2
477 		SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
478 		goto err;
479 #else
480 		/* we are talking sslv2 */
481 		/* we need to clean up the SSLv3/TLSv1 setup and put in the
482 		 * sslv2 stuff. */
483 
484 		if (s->s2 == NULL)
485 			{
486 			if (!ssl2_new(s))
487 				goto err;
488 			}
489 		else
490 			ssl2_clear(s);
491 
492 		if (s->s3 != NULL) ssl3_free(s);
493 
494 		if (!BUF_MEM_grow_clean(s->init_buf,
495 			SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
496 			{
497 			goto err;
498 			}
499 
500 		s->state=SSL2_ST_GET_CLIENT_HELLO_A;
501 		if (s->options & SSL_OP_NO_TLSv1 && s->options & SSL_OP_NO_SSLv3)
502 			s->s2->ssl2_rollback=0;
503 		else
504 			/* reject SSL 2.0 session if client supports SSL 3.0 or TLS 1.0
505 			 * (SSL 3.0 draft/RFC 2246, App. E.2) */
506 			s->s2->ssl2_rollback=1;
507 
508 		/* setup the n bytes we have read so we get them from
509 		 * the sslv2 buffer */
510 		s->rstate=SSL_ST_READ_HEADER;
511 		s->packet_length=n;
512 		s->packet= &(s->s2->rbuf[0]);
513 		memcpy(s->packet,buf,n);
514 		s->s2->rbuf_left=n;
515 		s->s2->rbuf_offs=0;
516 
517 		s->method=SSLv2_server_method();
518 		s->handshake_func=s->method->ssl_accept;
519 #endif
520 		}
521 
522 	if ((type == 2) || (type == 3))
523 		{
524 		/* we have SSLv3/TLSv1 (type 2: SSL2 style, type 3: SSL3/TLS style) */
525 
526 		if (!ssl_init_wbio_buffer(s,1)) goto err;
527 
528 		/* we are in this state */
529 		s->state=SSL3_ST_SR_CLNT_HELLO_A;
530 
531 		if (type == 3)
532 			{
533 			/* put the 'n' bytes we have read into the input buffer
534 			 * for SSLv3 */
535 			s->rstate=SSL_ST_READ_HEADER;
536 			s->packet_length=n;
537 			s->packet= &(s->s3->rbuf.buf[0]);
538 			memcpy(s->packet,buf,n);
539 			s->s3->rbuf.left=n;
540 			s->s3->rbuf.offset=0;
541 			}
542 		else
543 			{
544 			s->packet_length=0;
545 			s->s3->rbuf.left=0;
546 			s->s3->rbuf.offset=0;
547 			}
548 
549 		if (s->version == TLS1_VERSION)
550 			s->method = TLSv1_server_method();
551 		else
552 			s->method = SSLv3_server_method();
553 #if 0 /* ssl3_get_client_hello does this */
554 		s->client_version=(v[0]<<8)|v[1];
555 #endif
556 		s->handshake_func=s->method->ssl_accept;
557 		}
558 
559 	if ((type < 1) || (type > 3))
560 		{
561 		/* bad, very bad */
562 		SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNKNOWN_PROTOCOL);
563 		goto err;
564 		}
565 	s->init_num=0;
566 
567 	if (buf != buf_space) OPENSSL_free(buf);
568 	return(SSL_accept(s));
569 err:
570 	if (buf != buf_space) OPENSSL_free(buf);
571 	return(-1);
572 	}
573