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1 /* ssl/s3_pkt.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) 1998-2002 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 <errno.h>
114 #define USE_SOCKETS
115 #include "ssl_locl.h"
116 #include <openssl/evp.h>
117 #include <openssl/buffer.h>
118 
119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
120 			 unsigned int len, int create_empty_fragment);
121 static int ssl3_get_record(SSL *s);
122 
ssl3_read_n(SSL * s,int n,int max,int extend)123 int ssl3_read_n(SSL *s, int n, int max, int extend)
124 	{
125 	/* If extend == 0, obtain new n-byte packet; if extend == 1, increase
126 	 * packet by another n bytes.
127 	 * The packet will be in the sub-array of s->s3->rbuf.buf specified
128 	 * by s->packet and s->packet_length.
129 	 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
130 	 * [plus s->packet_length bytes if extend == 1].)
131 	 */
132 	int i,len,left;
133 	long align=0;
134 	unsigned char *pkt;
135 	SSL3_BUFFER *rb;
136 
137 	if (n <= 0) return n;
138 
139 	rb    = &(s->s3->rbuf);
140 	if (rb->buf == NULL)
141 		if (!ssl3_setup_read_buffer(s))
142 			return -1;
143 
144 	left  = rb->left;
145 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
146 	align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
147 	align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
148 #endif
149 
150 	if (!extend)
151 		{
152 		/* start with empty packet ... */
153 		if (left == 0)
154 			rb->offset = align;
155 		else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
156 			{
157 			/* check if next packet length is large
158 			 * enough to justify payload alignment... */
159 			pkt = rb->buf + rb->offset;
160 			if (pkt[0] == SSL3_RT_APPLICATION_DATA
161 			    && (pkt[3]<<8|pkt[4]) >= 128)
162 				{
163 				/* Note that even if packet is corrupted
164 				 * and its length field is insane, we can
165 				 * only be led to wrong decision about
166 				 * whether memmove will occur or not.
167 				 * Header values has no effect on memmove
168 				 * arguments and therefore no buffer
169 				 * overrun can be triggered. */
170 				memmove (rb->buf+align,pkt,left);
171 				rb->offset = align;
172 				}
173 			}
174 		s->packet = rb->buf + rb->offset;
175 		s->packet_length = 0;
176 		/* ... now we can act as if 'extend' was set */
177 		}
178 
179 	/* For DTLS/UDP reads should not span multiple packets
180 	 * because the read operation returns the whole packet
181 	 * at once (as long as it fits into the buffer). */
182 	if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
183 		{
184 		if (left > 0 && n > left)
185 			n = left;
186 		}
187 
188 	/* if there is enough in the buffer from a previous read, take some */
189 	if (left >= n)
190 		{
191 		s->packet_length+=n;
192 		rb->left=left-n;
193 		rb->offset+=n;
194 		return(n);
195 		}
196 
197 	/* else we need to read more data */
198 
199 	len = s->packet_length;
200 	pkt = rb->buf+align;
201 	/* Move any available bytes to front of buffer:
202 	 * 'len' bytes already pointed to by 'packet',
203 	 * 'left' extra ones at the end */
204 	if (s->packet != pkt) /* len > 0 */
205 		{
206 		memmove(pkt, s->packet, len+left);
207 		s->packet = pkt;
208 		rb->offset = len + align;
209 		}
210 
211 	if (n > (int)(rb->len - rb->offset)) /* does not happen */
212 		{
213 		SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
214 		return -1;
215 		}
216 
217 	if (!s->read_ahead)
218 		/* ignore max parameter */
219 		max = n;
220 	else
221 		{
222 		if (max < n)
223 			max = n;
224 		if (max > (int)(rb->len - rb->offset))
225 			max = rb->len - rb->offset;
226 		}
227 
228 	while (left < n)
229 		{
230 		/* Now we have len+left bytes at the front of s->s3->rbuf.buf
231 		 * and need to read in more until we have len+n (up to
232 		 * len+max if possible) */
233 
234 		clear_sys_error();
235 		if (s->rbio != NULL)
236 			{
237 			s->rwstate=SSL_READING;
238 			i=BIO_read(s->rbio,pkt+len+left, max-left);
239 			}
240 		else
241 			{
242 			SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
243 			i = -1;
244 			}
245 
246 		if (i <= 0)
247 			{
248 			rb->left = left;
249 			if (s->mode & SSL_MODE_RELEASE_BUFFERS)
250 				if (len+left == 0)
251 					ssl3_release_read_buffer(s);
252 			return(i);
253 			}
254 		left+=i;
255 		/* reads should *never* span multiple packets for DTLS because
256 		 * the underlying transport protocol is message oriented as opposed
257 		 * to byte oriented as in the TLS case. */
258 		if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
259 			{
260 			if (n > left)
261 				n = left; /* makes the while condition false */
262 			}
263 		}
264 
265 	/* done reading, now the book-keeping */
266 	rb->offset += n;
267 	rb->left = left - n;
268 	s->packet_length += n;
269 	s->rwstate=SSL_NOTHING;
270 	return(n);
271 	}
272 
273 /* Call this to get a new input record.
274  * It will return <= 0 if more data is needed, normally due to an error
275  * or non-blocking IO.
276  * When it finishes, one packet has been decoded and can be found in
277  * ssl->s3->rrec.type    - is the type of record
278  * ssl->s3->rrec.data, 	 - data
279  * ssl->s3->rrec.length, - number of bytes
280  */
281 /* used only by ssl3_read_bytes */
ssl3_get_record(SSL * s)282 static int ssl3_get_record(SSL *s)
283 	{
284 	int ssl_major,ssl_minor,al;
285 	int enc_err,n,i,ret= -1;
286 	SSL3_RECORD *rr;
287 	SSL_SESSION *sess;
288 	unsigned char *p;
289 	unsigned char md[EVP_MAX_MD_SIZE];
290 	short version;
291 	int mac_size;
292 	int clear=0;
293 	size_t extra;
294 	int decryption_failed_or_bad_record_mac = 0;
295 	unsigned char *mac = NULL;
296 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
297 	long align=SSL3_ALIGN_PAYLOAD;
298 #else
299 	long align=0;
300 #endif
301 
302 	rr= &(s->s3->rrec);
303 	sess=s->session;
304 
305 	if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
306 		extra=SSL3_RT_MAX_EXTRA;
307 	else
308 		extra=0;
309 	if (!(SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS) &&
310 		extra && !s->s3->init_extra)
311 		{
312 		/* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
313 		 * set after ssl3_setup_buffers() was done */
314 		SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
315 		return -1;
316 		}
317 
318 again:
319 	/* check if we have the header */
320 	if (	(s->rstate != SSL_ST_READ_BODY) ||
321 		(s->packet_length < SSL3_RT_HEADER_LENGTH))
322 		{
323 		n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
324 		if (n <= 0) return(n); /* error or non-blocking */
325 		s->rstate=SSL_ST_READ_BODY;
326 
327 		p=s->packet;
328 
329 		/* Pull apart the header into the SSL3_RECORD */
330 		rr->type= *(p++);
331 		ssl_major= *(p++);
332 		ssl_minor= *(p++);
333 		version=(ssl_major<<8)|ssl_minor;
334 		n2s(p,rr->length);
335 #if 0
336 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
337 #endif
338 
339 		/* Lets check version */
340 		if (!s->first_packet)
341 			{
342 			if (version != s->version)
343 				{
344 				SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
345                                 if ((s->version & 0xFF00) == (version & 0xFF00))
346                                 	/* Send back error using their minor version number :-) */
347 					s->version = (unsigned short)version;
348 				al=SSL_AD_PROTOCOL_VERSION;
349 				goto f_err;
350 				}
351 			}
352 
353 		if ((version>>8) != SSL3_VERSION_MAJOR)
354 			{
355 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
356 			goto err;
357 			}
358 
359 		/* If we receive a valid record larger than the current buffer size,
360 		 * allocate some memory for it.
361 		 */
362 		if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH - align)
363 			{
364 			if ((p=OPENSSL_realloc(s->s3->rbuf.buf, rr->length + SSL3_RT_HEADER_LENGTH + align))==NULL)
365 				{
366 				SSLerr(SSL_F_SSL3_GET_RECORD,ERR_R_MALLOC_FAILURE);
367 				goto err;
368 				}
369 			s->s3->rbuf.buf=p;
370 			s->s3->rbuf.len=rr->length + SSL3_RT_HEADER_LENGTH + align;
371 			s->packet= &(s->s3->rbuf.buf[0]);
372 			}
373 
374 		if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
375 			{
376 			al=SSL_AD_RECORD_OVERFLOW;
377 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
378 			goto f_err;
379 			}
380 
381 		/* now s->rstate == SSL_ST_READ_BODY */
382 		}
383 
384 	/* s->rstate == SSL_ST_READ_BODY, get and decode the data */
385 
386 	if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
387 		{
388 		/* now s->packet_length == SSL3_RT_HEADER_LENGTH */
389 		i=rr->length;
390 		n=ssl3_read_n(s,i,i,1);
391 		if (n <= 0) return(n); /* error or non-blocking io */
392 		/* now n == rr->length,
393 		 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
394 		}
395 
396 	s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
397 
398 	/* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
399 	 * and we have that many bytes in s->packet
400 	 */
401 	rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
402 
403 	/* ok, we can now read from 's->packet' data into 'rr'
404 	 * rr->input points at rr->length bytes, which
405 	 * need to be copied into rr->data by either
406 	 * the decryption or by the decompression
407 	 * When the data is 'copied' into the rr->data buffer,
408 	 * rr->input will be pointed at the new buffer */
409 
410 	/* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
411 	 * rr->length bytes of encrypted compressed stuff. */
412 
413 	/* check is not needed I believe */
414 	if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
415 		{
416 		al=SSL_AD_RECORD_OVERFLOW;
417 		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
418 		goto f_err;
419 		}
420 
421 	/* decrypt in place in 'rr->input' */
422 	rr->data=rr->input;
423 
424 	enc_err = s->method->ssl3_enc->enc(s,0);
425 	if (enc_err <= 0)
426 		{
427 		if (enc_err == 0)
428 			/* SSLerr() and ssl3_send_alert() have been called */
429 			goto err;
430 
431 		/* Otherwise enc_err == -1, which indicates bad padding
432 		 * (rec->length has not been changed in this case).
433 		 * To minimize information leaked via timing, we will perform
434 		 * the MAC computation anyway. */
435 		decryption_failed_or_bad_record_mac = 1;
436 		}
437 
438 #ifdef TLS_DEBUG
439 printf("dec %d\n",rr->length);
440 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
441 printf("\n");
442 #endif
443 
444 	/* r->length is now the compressed data plus mac */
445 	if (	(sess == NULL) ||
446 		(s->enc_read_ctx == NULL) ||
447 		(EVP_MD_CTX_md(s->read_hash) == NULL))
448 		clear=1;
449 
450 	if (!clear)
451 		{
452 		/* !clear => s->read_hash != NULL => mac_size != -1 */
453 		mac_size=EVP_MD_CTX_size(s->read_hash);
454 		OPENSSL_assert(mac_size >= 0);
455 
456 		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
457 			{
458 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
459 			al=SSL_AD_RECORD_OVERFLOW;
460 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
461 			goto f_err;
462 #else
463 			decryption_failed_or_bad_record_mac = 1;
464 #endif
465 			}
466 		/* check the MAC for rr->input (it's in mac_size bytes at the tail) */
467 		if (rr->length >= (unsigned int)mac_size)
468 			{
469 			rr->length -= mac_size;
470 			mac = &rr->data[rr->length];
471 			}
472 		else
473 			{
474 			/* record (minus padding) is too short to contain a MAC */
475 #if 0 /* OK only for stream ciphers */
476 			al=SSL_AD_DECODE_ERROR;
477 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
478 			goto f_err;
479 #else
480 			decryption_failed_or_bad_record_mac = 1;
481 			rr->length = 0;
482 #endif
483 			}
484 		i=s->method->ssl3_enc->mac(s,md,0);
485 		if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0)
486 			{
487 			decryption_failed_or_bad_record_mac = 1;
488 			}
489 		}
490 
491 	if (decryption_failed_or_bad_record_mac)
492 		{
493 		/* A separate 'decryption_failed' alert was introduced with TLS 1.0,
494 		 * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
495 		 * failure is directly visible from the ciphertext anyway,
496 		 * we should not reveal which kind of error occured -- this
497 		 * might become visible to an attacker (e.g. via a logfile) */
498 		al=SSL_AD_BAD_RECORD_MAC;
499 		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
500 		goto f_err;
501 		}
502 
503 	/* r->length is now just compressed */
504 	if (s->expand != NULL)
505 		{
506 		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
507 			{
508 			al=SSL_AD_RECORD_OVERFLOW;
509 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
510 			goto f_err;
511 			}
512 		if (!ssl3_do_uncompress(s))
513 			{
514 			al=SSL_AD_DECOMPRESSION_FAILURE;
515 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
516 			goto f_err;
517 			}
518 		}
519 
520 	if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
521 		{
522 		al=SSL_AD_RECORD_OVERFLOW;
523 		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
524 		goto f_err;
525 		}
526 
527 	rr->off=0;
528 	/* So at this point the following is true
529 	 * ssl->s3->rrec.type 	is the type of record
530 	 * ssl->s3->rrec.length	== number of bytes in record
531 	 * ssl->s3->rrec.off	== offset to first valid byte
532 	 * ssl->s3->rrec.data	== where to take bytes from, increment
533 	 *			   after use :-).
534 	 */
535 
536 	/* we have pulled in a full packet so zero things */
537 	s->packet_length=0;
538 
539 	/* just read a 0 length packet */
540 	if (rr->length == 0) goto again;
541 
542 #if 0
543 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
544 #endif
545 
546 	return(1);
547 
548 f_err:
549 	ssl3_send_alert(s,SSL3_AL_FATAL,al);
550 err:
551 	return(ret);
552 	}
553 
ssl3_do_uncompress(SSL * ssl)554 int ssl3_do_uncompress(SSL *ssl)
555 	{
556 #ifndef OPENSSL_NO_COMP
557 	int i;
558 	SSL3_RECORD *rr;
559 
560 	rr= &(ssl->s3->rrec);
561 	i=COMP_expand_block(ssl->expand,rr->comp,
562 		SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
563 	if (i < 0)
564 		return(0);
565 	else
566 		rr->length=i;
567 	rr->data=rr->comp;
568 #endif
569 	return(1);
570 	}
571 
ssl3_do_compress(SSL * ssl)572 int ssl3_do_compress(SSL *ssl)
573 	{
574 #ifndef OPENSSL_NO_COMP
575 	int i;
576 	SSL3_RECORD *wr;
577 
578 	wr= &(ssl->s3->wrec);
579 	i=COMP_compress_block(ssl->compress,wr->data,
580 		SSL3_RT_MAX_COMPRESSED_LENGTH,
581 		wr->input,(int)wr->length);
582 	if (i < 0)
583 		return(0);
584 	else
585 		wr->length=i;
586 
587 	wr->input=wr->data;
588 #endif
589 	return(1);
590 	}
591 
592 /* Call this to write data in records of type 'type'
593  * It will return <= 0 if not all data has been sent or non-blocking IO.
594  */
ssl3_write_bytes(SSL * s,int type,const void * buf_,int len)595 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
596 	{
597 	const unsigned char *buf=buf_;
598 	unsigned int tot,n,nw;
599 	int i;
600 	unsigned int max_plain_length;
601 
602 	s->rwstate=SSL_NOTHING;
603 	tot=s->s3->wnum;
604 	s->s3->wnum=0;
605 
606 	if (SSL_in_init(s) && !s->in_handshake)
607 		{
608 		i=s->handshake_func(s);
609 		if (i < 0) return(i);
610 		if (i == 0)
611 			{
612 			SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
613 			return -1;
614 			}
615 		}
616 
617 	n=(len-tot);
618 	for (;;)
619 		{
620 		if (type == SSL3_RT_APPLICATION_DATA && (SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS))
621 			max_plain_length = SSL3_RT_DEFAULT_PLAIN_LENGTH;
622 		else
623 			max_plain_length = s->max_send_fragment;
624 
625 		if (n > max_plain_length)
626 			nw = max_plain_length;
627 		else
628 			nw=n;
629 
630 		i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
631 		if (i <= 0)
632 			{
633 			s->s3->wnum=tot;
634 			return i;
635 			}
636 
637 		if ((i == (int)n) ||
638 			(type == SSL3_RT_APPLICATION_DATA &&
639 			 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
640 			{
641 			/* next chunk of data should get another prepended empty fragment
642 			 * in ciphersuites with known-IV weakness: */
643 			s->s3->empty_fragment_done = 0;
644 
645 			return tot+i;
646 			}
647 
648 		n-=i;
649 		tot+=i;
650 		}
651 	}
652 
do_ssl3_write(SSL * s,int type,const unsigned char * buf,unsigned int len,int create_empty_fragment)653 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
654 			 unsigned int len, int create_empty_fragment)
655 	{
656 	unsigned char *p,*plen;
657 	int i,mac_size,clear=0;
658 	int prefix_len=0;
659 	long align=0;
660 	SSL3_RECORD *wr;
661 	SSL3_BUFFER *wb=&(s->s3->wbuf);
662 	SSL_SESSION *sess;
663 
664  	if (wb->buf == NULL)
665 		if (!ssl3_setup_write_buffer(s))
666 			return -1;
667 
668 	/* first check if there is a SSL3_BUFFER still being written
669 	 * out.  This will happen with non blocking IO */
670 	if (wb->left != 0)
671 		return(ssl3_write_pending(s,type,buf,len));
672 
673 	/* If we have an alert to send, lets send it */
674 	if (s->s3->alert_dispatch)
675 		{
676 		i=s->method->ssl_dispatch_alert(s);
677 		if (i <= 0)
678 			return(i);
679 		/* if it went, fall through and send more stuff */
680 		}
681 
682 	if (len == 0 && !create_empty_fragment)
683 		return 0;
684 
685 	wr= &(s->s3->wrec);
686 	sess=s->session;
687 
688 	if (	(sess == NULL) ||
689 		(s->enc_write_ctx == NULL) ||
690 		(EVP_MD_CTX_md(s->write_hash) == NULL))
691 		clear=1;
692 
693 	if (clear)
694 		mac_size=0;
695 	else
696 		{
697 		mac_size=EVP_MD_CTX_size(s->write_hash);
698 		if (mac_size < 0)
699 			goto err;
700 		}
701 
702 	/* 'create_empty_fragment' is true only when this function calls itself */
703 	if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
704 		{
705 		/* countermeasure against known-IV weakness in CBC ciphersuites
706 		 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
707 
708 		if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
709 			{
710 			/* recursive function call with 'create_empty_fragment' set;
711 			 * this prepares and buffers the data for an empty fragment
712 			 * (these 'prefix_len' bytes are sent out later
713 			 * together with the actual payload) */
714 			prefix_len = do_ssl3_write(s, type, buf, 0, 1);
715 			if (prefix_len <= 0)
716 				goto err;
717 
718 			if (prefix_len >
719 		(SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
720 				{
721 				/* insufficient space */
722 				SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
723 				goto err;
724 				}
725 			}
726 
727 		s->s3->empty_fragment_done = 1;
728 		}
729 
730 	/* resize if necessary to hold the data. */
731 	if (len + SSL3_RT_DEFAULT_WRITE_OVERHEAD > wb->len)
732 		{
733 		if ((p=OPENSSL_realloc(wb->buf, len + SSL3_RT_DEFAULT_WRITE_OVERHEAD))==NULL)
734 			{
735 			SSLerr(SSL_F_DO_SSL3_WRITE,ERR_R_MALLOC_FAILURE);
736 			goto err;
737 			}
738 		wb->buf = p;
739 		wb->len = len + SSL3_RT_DEFAULT_WRITE_OVERHEAD;
740 		}
741 
742 	if (create_empty_fragment)
743 		{
744 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
745 		/* extra fragment would be couple of cipher blocks,
746 		 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
747 		 * if we want to align the real payload, then we can
748 		 * just pretent we simply have two headers. */
749 		align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
750 		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
751 #endif
752 		p = wb->buf + align;
753 		wb->offset  = align;
754 		}
755 	else if (prefix_len)
756 		{
757 		p = wb->buf + wb->offset + prefix_len;
758 		}
759 	else
760 		{
761 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
762 		align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
763 		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
764 #endif
765 		p = wb->buf + align;
766 		wb->offset  = align;
767 		}
768 
769 	/* write the header */
770 
771 	*(p++)=type&0xff;
772 	wr->type=type;
773 
774 	*(p++)=(s->version>>8);
775 	*(p++)=s->version&0xff;
776 
777 	/* field where we are to write out packet length */
778 	plen=p;
779 	p+=2;
780 
781 	/* lets setup the record stuff. */
782 	wr->data=p;
783 	wr->length=(int)len;
784 	wr->input=(unsigned char *)buf;
785 
786 	/* we now 'read' from wr->input, wr->length bytes into
787 	 * wr->data */
788 
789 	/* first we compress */
790 	if (s->compress != NULL)
791 		{
792 		if (!ssl3_do_compress(s))
793 			{
794 			SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
795 			goto err;
796 			}
797 		}
798 	else
799 		{
800 		memcpy(wr->data,wr->input,wr->length);
801 		wr->input=wr->data;
802 		}
803 
804 	/* we should still have the output to wr->data and the input
805 	 * from wr->input.  Length should be wr->length.
806 	 * wr->data still points in the wb->buf */
807 
808 	if (mac_size != 0)
809 		{
810 		if (s->method->ssl3_enc->mac(s,&(p[wr->length]),1) < 0)
811 			goto err;
812 		wr->length+=mac_size;
813 		wr->input=p;
814 		wr->data=p;
815 		}
816 
817 	/* ssl3_enc can only have an error on read */
818 	s->method->ssl3_enc->enc(s,1);
819 
820 	/* record length after mac and block padding */
821 	s2n(wr->length,plen);
822 
823 	/* we should now have
824 	 * wr->data pointing to the encrypted data, which is
825 	 * wr->length long */
826 	wr->type=type; /* not needed but helps for debugging */
827 	wr->length+=SSL3_RT_HEADER_LENGTH;
828 
829 	if (create_empty_fragment)
830 		{
831 		/* we are in a recursive call;
832 		 * just return the length, don't write out anything here
833 		 */
834 		return wr->length;
835 		}
836 
837 	/* now let's set up wb */
838 	wb->left = prefix_len + wr->length;
839 
840 	/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
841 	s->s3->wpend_tot=len;
842 	s->s3->wpend_buf=buf;
843 	s->s3->wpend_type=type;
844 	s->s3->wpend_ret=len;
845 
846 	/* we now just need to write the buffer */
847 	return ssl3_write_pending(s,type,buf,len);
848 err:
849 	return -1;
850 	}
851 
852 /* if s->s3->wbuf.left != 0, we need to call this */
ssl3_write_pending(SSL * s,int type,const unsigned char * buf,unsigned int len)853 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
854 	unsigned int len)
855 	{
856 	int i;
857 	SSL3_BUFFER *wb=&(s->s3->wbuf);
858 
859 /* XXXX */
860 	if ((s->s3->wpend_tot > (int)len)
861 		|| ((s->s3->wpend_buf != buf) &&
862 			!(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
863 		|| (s->s3->wpend_type != type))
864 		{
865 		SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
866 		return(-1);
867 		}
868 
869 	for (;;)
870 		{
871 		clear_sys_error();
872 		if (s->wbio != NULL)
873 			{
874 			s->rwstate=SSL_WRITING;
875 			i=BIO_write(s->wbio,
876 				(char *)&(wb->buf[wb->offset]),
877 				(unsigned int)wb->left);
878 			}
879 		else
880 			{
881 			SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
882 			i= -1;
883 			}
884 		if (i == wb->left)
885 			{
886 			wb->left=0;
887 			wb->offset+=i;
888 			if (s->mode & SSL_MODE_RELEASE_BUFFERS)
889 				ssl3_release_write_buffer(s);
890 			s->rwstate=SSL_NOTHING;
891 			return(s->s3->wpend_ret);
892 			}
893 		else if (i <= 0) {
894 			if (s->version == DTLS1_VERSION ||
895 			    s->version == DTLS1_BAD_VER) {
896 				/* For DTLS, just drop it. That's kind of the whole
897 				   point in using a datagram service */
898 				wb->left = 0;
899 			}
900 			return(i);
901 		}
902 		wb->offset+=i;
903 		wb->left-=i;
904 		}
905 	}
906 
907 /* Return up to 'len' payload bytes received in 'type' records.
908  * 'type' is one of the following:
909  *
910  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
911  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
912  *   -  0 (during a shutdown, no data has to be returned)
913  *
914  * If we don't have stored data to work from, read a SSL/TLS record first
915  * (possibly multiple records if we still don't have anything to return).
916  *
917  * This function must handle any surprises the peer may have for us, such as
918  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
919  * a surprise, but handled as if it were), or renegotiation requests.
920  * Also if record payloads contain fragments too small to process, we store
921  * them until there is enough for the respective protocol (the record protocol
922  * may use arbitrary fragmentation and even interleaving):
923  *     Change cipher spec protocol
924  *             just 1 byte needed, no need for keeping anything stored
925  *     Alert protocol
926  *             2 bytes needed (AlertLevel, AlertDescription)
927  *     Handshake protocol
928  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
929  *             to detect unexpected Client Hello and Hello Request messages
930  *             here, anything else is handled by higher layers
931  *     Application data protocol
932  *             none of our business
933  */
ssl3_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)934 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
935 	{
936 	int al,i,j,ret;
937 	unsigned int n;
938 	SSL3_RECORD *rr;
939 	void (*cb)(const SSL *ssl,int type2,int val)=NULL;
940 
941 	if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
942 		if (!ssl3_setup_read_buffer(s))
943 			return(-1);
944 
945 	if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
946 	    (peek && (type != SSL3_RT_APPLICATION_DATA)))
947 		{
948 		SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
949 		return -1;
950 		}
951 
952 	if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
953 		/* (partially) satisfy request from storage */
954 		{
955 		unsigned char *src = s->s3->handshake_fragment;
956 		unsigned char *dst = buf;
957 		unsigned int k;
958 
959 		/* peek == 0 */
960 		n = 0;
961 		while ((len > 0) && (s->s3->handshake_fragment_len > 0))
962 			{
963 			*dst++ = *src++;
964 			len--; s->s3->handshake_fragment_len--;
965 			n++;
966 			}
967 		/* move any remaining fragment bytes: */
968 		for (k = 0; k < s->s3->handshake_fragment_len; k++)
969 			s->s3->handshake_fragment[k] = *src++;
970 		return n;
971 	}
972 
973 	/* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
974 
975 	if (!s->in_handshake && SSL_in_init(s))
976 		{
977 		/* type == SSL3_RT_APPLICATION_DATA */
978 		i=s->handshake_func(s);
979 		if (i < 0) return(i);
980 		if (i == 0)
981 			{
982 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
983 			return(-1);
984 			}
985 		}
986 start:
987 	s->rwstate=SSL_NOTHING;
988 
989 	/* s->s3->rrec.type	    - is the type of record
990 	 * s->s3->rrec.data,    - data
991 	 * s->s3->rrec.off,     - offset into 'data' for next read
992 	 * s->s3->rrec.length,  - number of bytes. */
993 	rr = &(s->s3->rrec);
994 
995 	/* get new packet if necessary */
996 	if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
997 		{
998 		ret=ssl3_get_record(s);
999 		if (ret <= 0) return(ret);
1000 		}
1001 
1002 	/* we now have a packet which can be read and processed */
1003 
1004 	if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1005 	                               * reset by ssl3_get_finished */
1006 		&& (rr->type != SSL3_RT_HANDSHAKE))
1007 		{
1008 		al=SSL_AD_UNEXPECTED_MESSAGE;
1009 		SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1010 		goto f_err;
1011 		}
1012 
1013 	/* If the other end has shut down, throw anything we read away
1014 	 * (even in 'peek' mode) */
1015 	if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1016 		{
1017 		rr->length=0;
1018 		s->rwstate=SSL_NOTHING;
1019 		return(0);
1020 		}
1021 
1022 
1023 	if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1024 		{
1025 		/* make sure that we are not getting application data when we
1026 		 * are doing a handshake for the first time */
1027 		if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1028 			(s->enc_read_ctx == NULL))
1029 			{
1030 			al=SSL_AD_UNEXPECTED_MESSAGE;
1031 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1032 			goto f_err;
1033 			}
1034 
1035 		if (len <= 0) return(len);
1036 
1037 		if ((unsigned int)len > rr->length)
1038 			n = rr->length;
1039 		else
1040 			n = (unsigned int)len;
1041 
1042 		memcpy(buf,&(rr->data[rr->off]),n);
1043 		if (!peek)
1044 			{
1045 			rr->length-=n;
1046 			rr->off+=n;
1047 			if (rr->length == 0)
1048 				{
1049 				s->rstate=SSL_ST_READ_HEADER;
1050 				rr->off=0;
1051 				if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1052 					ssl3_release_read_buffer(s);
1053 				}
1054 			}
1055 		return(n);
1056 		}
1057 
1058 
1059 	/* If we get here, then type != rr->type; if we have a handshake
1060 	 * message, then it was unexpected (Hello Request or Client Hello). */
1061 
1062 	/* In case of record types for which we have 'fragment' storage,
1063 	 * fill that so that we can process the data at a fixed place.
1064 	 */
1065 		{
1066 		unsigned int dest_maxlen = 0;
1067 		unsigned char *dest = NULL;
1068 		unsigned int *dest_len = NULL;
1069 
1070 		if (rr->type == SSL3_RT_HANDSHAKE)
1071 			{
1072 			dest_maxlen = sizeof s->s3->handshake_fragment;
1073 			dest = s->s3->handshake_fragment;
1074 			dest_len = &s->s3->handshake_fragment_len;
1075 			}
1076 		else if (rr->type == SSL3_RT_ALERT)
1077 			{
1078 			dest_maxlen = sizeof s->s3->alert_fragment;
1079 			dest = s->s3->alert_fragment;
1080 			dest_len = &s->s3->alert_fragment_len;
1081 			}
1082 
1083 		if (dest_maxlen > 0)
1084 			{
1085 			n = dest_maxlen - *dest_len; /* available space in 'dest' */
1086 			if (rr->length < n)
1087 				n = rr->length; /* available bytes */
1088 
1089 			/* now move 'n' bytes: */
1090 			while (n-- > 0)
1091 				{
1092 				dest[(*dest_len)++] = rr->data[rr->off++];
1093 				rr->length--;
1094 				}
1095 
1096 			if (*dest_len < dest_maxlen)
1097 				goto start; /* fragment was too small */
1098 			}
1099 		}
1100 
1101 	/* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1102 	 * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1103 	 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1104 
1105 	/* If we are a client, check for an incoming 'Hello Request': */
1106 	if ((!s->server) &&
1107 		(s->s3->handshake_fragment_len >= 4) &&
1108 		(s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1109 		(s->session != NULL) && (s->session->cipher != NULL))
1110 		{
1111 		s->s3->handshake_fragment_len = 0;
1112 
1113 		if ((s->s3->handshake_fragment[1] != 0) ||
1114 			(s->s3->handshake_fragment[2] != 0) ||
1115 			(s->s3->handshake_fragment[3] != 0))
1116 			{
1117 			al=SSL_AD_DECODE_ERROR;
1118 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1119 			goto f_err;
1120 			}
1121 
1122 		if (s->msg_callback)
1123 			s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1124 
1125 		if (SSL_is_init_finished(s) &&
1126 			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1127 			!s->s3->renegotiate)
1128 			{
1129 			ssl3_renegotiate(s);
1130 			if (ssl3_renegotiate_check(s))
1131 				{
1132 				i=s->handshake_func(s);
1133 				if (i < 0) return(i);
1134 				if (i == 0)
1135 					{
1136 					SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1137 					return(-1);
1138 					}
1139 
1140 				if (!(s->mode & SSL_MODE_AUTO_RETRY))
1141 					{
1142 					if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1143 						{
1144 						BIO *bio;
1145 						/* In the case where we try to read application data,
1146 						 * but we trigger an SSL handshake, we return -1 with
1147 						 * the retry option set.  Otherwise renegotiation may
1148 						 * cause nasty problems in the blocking world */
1149 						s->rwstate=SSL_READING;
1150 						bio=SSL_get_rbio(s);
1151 						BIO_clear_retry_flags(bio);
1152 						BIO_set_retry_read(bio);
1153 						return(-1);
1154 						}
1155 					}
1156 				}
1157 			}
1158 		/* we either finished a handshake or ignored the request,
1159 		 * now try again to obtain the (application) data we were asked for */
1160 		goto start;
1161 		}
1162 	/* If we are a server and get a client hello when renegotiation isn't
1163 	 * allowed send back a no renegotiation alert and carry on.
1164 	 * WARNING: experimental code, needs reviewing (steve)
1165 	 */
1166 	if (s->server &&
1167 		SSL_is_init_finished(s) &&
1168     		!s->s3->send_connection_binding &&
1169 		(s->version > SSL3_VERSION) &&
1170 		(s->s3->handshake_fragment_len >= 4) &&
1171 		(s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1172 		(s->session != NULL) && (s->session->cipher != NULL) &&
1173 		!(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1174 
1175 		{
1176 		/*s->s3->handshake_fragment_len = 0;*/
1177 		rr->length = 0;
1178 		ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1179 		goto start;
1180 		}
1181 	if (s->s3->alert_fragment_len >= 2)
1182 		{
1183 		int alert_level = s->s3->alert_fragment[0];
1184 		int alert_descr = s->s3->alert_fragment[1];
1185 
1186 		s->s3->alert_fragment_len = 0;
1187 
1188 		if (s->msg_callback)
1189 			s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1190 
1191 		if (s->info_callback != NULL)
1192 			cb=s->info_callback;
1193 		else if (s->ctx->info_callback != NULL)
1194 			cb=s->ctx->info_callback;
1195 
1196 		if (cb != NULL)
1197 			{
1198 			j = (alert_level << 8) | alert_descr;
1199 			cb(s, SSL_CB_READ_ALERT, j);
1200 			}
1201 
1202 		if (alert_level == 1) /* warning */
1203 			{
1204 			s->s3->warn_alert = alert_descr;
1205 			if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1206 				{
1207 				s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1208 				return(0);
1209 				}
1210 			/* This is a warning but we receive it if we requested
1211 			 * renegotiation and the peer denied it. Terminate with
1212 			 * a fatal alert because if application tried to
1213 			 * renegotiatie it presumably had a good reason and
1214 			 * expects it to succeed.
1215 			 *
1216 			 * In future we might have a renegotiation where we
1217 			 * don't care if the peer refused it where we carry on.
1218 			 */
1219 			else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1220 				{
1221 				al = SSL_AD_HANDSHAKE_FAILURE;
1222 				SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1223 				goto f_err;
1224 				}
1225 			}
1226 		else if (alert_level == 2) /* fatal */
1227 			{
1228 			char tmp[16];
1229 
1230 			s->rwstate=SSL_NOTHING;
1231 			s->s3->fatal_alert = alert_descr;
1232 			SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1233 			BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1234 			ERR_add_error_data(2,"SSL alert number ",tmp);
1235 			s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1236 			SSL_CTX_remove_session(s->ctx,s->session);
1237 			return(0);
1238 			}
1239 		else
1240 			{
1241 			al=SSL_AD_ILLEGAL_PARAMETER;
1242 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1243 			goto f_err;
1244 			}
1245 
1246 		goto start;
1247 		}
1248 
1249 	if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1250 		{
1251 		s->rwstate=SSL_NOTHING;
1252 		rr->length=0;
1253 		return(0);
1254 		}
1255 
1256 	if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1257 		{
1258 		/* 'Change Cipher Spec' is just a single byte, so we know
1259 		 * exactly what the record payload has to look like */
1260 		if (	(rr->length != 1) || (rr->off != 0) ||
1261 			(rr->data[0] != SSL3_MT_CCS))
1262 			{
1263 			al=SSL_AD_ILLEGAL_PARAMETER;
1264 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1265 			goto f_err;
1266 			}
1267 
1268 		/* Check we have a cipher to change to */
1269 		if (s->s3->tmp.new_cipher == NULL)
1270 			{
1271 			al=SSL_AD_UNEXPECTED_MESSAGE;
1272 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1273 			goto f_err;
1274 			}
1275 
1276 		rr->length=0;
1277 
1278 		if (s->msg_callback)
1279 			s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1280 
1281 		s->s3->change_cipher_spec=1;
1282 		if (!ssl3_do_change_cipher_spec(s))
1283 			goto err;
1284 		else
1285 			goto start;
1286 		}
1287 
1288 	/* Unexpected handshake message (Client Hello, or protocol violation) */
1289 	if ((s->s3->handshake_fragment_len >= 4) &&	!s->in_handshake)
1290 		{
1291 		if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1292 			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1293 			{
1294 #if 0 /* worked only because C operator preferences are not as expected (and
1295        * because this is not really needed for clients except for detecting
1296        * protocol violations): */
1297 			s->state=SSL_ST_BEFORE|(s->server)
1298 				?SSL_ST_ACCEPT
1299 				:SSL_ST_CONNECT;
1300 #else
1301 			s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1302 #endif
1303 			s->new_session=1;
1304 			}
1305 		i=s->handshake_func(s);
1306 		if (i < 0) return(i);
1307 		if (i == 0)
1308 			{
1309 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1310 			return(-1);
1311 			}
1312 
1313 		if (!(s->mode & SSL_MODE_AUTO_RETRY))
1314 			{
1315 			if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1316 				{
1317 				BIO *bio;
1318 				/* In the case where we try to read application data,
1319 				 * but we trigger an SSL handshake, we return -1 with
1320 				 * the retry option set.  Otherwise renegotiation may
1321 				 * cause nasty problems in the blocking world */
1322 				s->rwstate=SSL_READING;
1323 				bio=SSL_get_rbio(s);
1324 				BIO_clear_retry_flags(bio);
1325 				BIO_set_retry_read(bio);
1326 				return(-1);
1327 				}
1328 			}
1329 		goto start;
1330 		}
1331 
1332 	switch (rr->type)
1333 		{
1334 	default:
1335 #ifndef OPENSSL_NO_TLS
1336 		/* TLS just ignores unknown message types */
1337 		if (s->version == TLS1_VERSION)
1338 			{
1339 			rr->length = 0;
1340 			goto start;
1341 			}
1342 #endif
1343 		al=SSL_AD_UNEXPECTED_MESSAGE;
1344 		SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1345 		goto f_err;
1346 	case SSL3_RT_CHANGE_CIPHER_SPEC:
1347 	case SSL3_RT_ALERT:
1348 	case SSL3_RT_HANDSHAKE:
1349 		/* we already handled all of these, with the possible exception
1350 		 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1351 		 * should not happen when type != rr->type */
1352 		al=SSL_AD_UNEXPECTED_MESSAGE;
1353 		SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1354 		goto f_err;
1355 	case SSL3_RT_APPLICATION_DATA:
1356 		/* At this point, we were expecting handshake data,
1357 		 * but have application data.  If the library was
1358 		 * running inside ssl3_read() (i.e. in_read_app_data
1359 		 * is set) and it makes sense to read application data
1360 		 * at this point (session renegotiation not yet started),
1361 		 * we will indulge it.
1362 		 */
1363 		if (s->s3->in_read_app_data &&
1364 			(s->s3->total_renegotiations != 0) &&
1365 			((
1366 				(s->state & SSL_ST_CONNECT) &&
1367 				(s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1368 				(s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1369 				) || (
1370 					(s->state & SSL_ST_ACCEPT) &&
1371 					(s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1372 					(s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1373 					)
1374 				))
1375 			{
1376 			s->s3->in_read_app_data=2;
1377 			return(-1);
1378 			}
1379 		else
1380 			{
1381 			al=SSL_AD_UNEXPECTED_MESSAGE;
1382 			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1383 			goto f_err;
1384 			}
1385 		}
1386 	/* not reached */
1387 
1388 f_err:
1389 	ssl3_send_alert(s,SSL3_AL_FATAL,al);
1390 err:
1391 	return(-1);
1392 	}
1393 
ssl3_do_change_cipher_spec(SSL * s)1394 int ssl3_do_change_cipher_spec(SSL *s)
1395 	{
1396 	int i;
1397 	const char *sender;
1398 	int slen;
1399 
1400 	if (s->state & SSL_ST_ACCEPT)
1401 		i=SSL3_CHANGE_CIPHER_SERVER_READ;
1402 	else
1403 		i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1404 
1405 	if (s->s3->tmp.key_block == NULL)
1406 		{
1407 		if (s->session == NULL)
1408 			{
1409 			/* might happen if dtls1_read_bytes() calls this */
1410 			SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1411 			return (0);
1412 			}
1413 
1414 		s->session->cipher=s->s3->tmp.new_cipher;
1415 		if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1416 		}
1417 
1418 	if (!s->method->ssl3_enc->change_cipher_state(s,i))
1419 		return(0);
1420 
1421 	/* we have to record the message digest at
1422 	 * this point so we can get it before we read
1423 	 * the finished message */
1424 	if (s->state & SSL_ST_CONNECT)
1425 		{
1426 		sender=s->method->ssl3_enc->server_finished_label;
1427 		slen=s->method->ssl3_enc->server_finished_label_len;
1428 		}
1429 	else
1430 		{
1431 		sender=s->method->ssl3_enc->client_finished_label;
1432 		slen=s->method->ssl3_enc->client_finished_label_len;
1433 		}
1434 
1435 	s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1436 		sender,slen,s->s3->tmp.peer_finish_md);
1437 
1438 	return(1);
1439 	}
1440 
ssl3_send_alert(SSL * s,int level,int desc)1441 int ssl3_send_alert(SSL *s, int level, int desc)
1442 	{
1443 	/* Map tls/ssl alert value to correct one */
1444 	desc=s->method->ssl3_enc->alert_value(desc);
1445 	if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1446 		desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1447 	if (desc < 0) return -1;
1448 	/* If a fatal one, remove from cache */
1449 	if ((level == 2) && (s->session != NULL))
1450 		SSL_CTX_remove_session(s->ctx,s->session);
1451 
1452 	s->s3->alert_dispatch=1;
1453 	s->s3->send_alert[0]=level;
1454 	s->s3->send_alert[1]=desc;
1455 	if (s->s3->wbuf.left == 0) /* data still being written out? */
1456 		return s->method->ssl_dispatch_alert(s);
1457 	/* else data is still being written out, we will get written
1458 	 * some time in the future */
1459 	return -1;
1460 	}
1461 
ssl3_dispatch_alert(SSL * s)1462 int ssl3_dispatch_alert(SSL *s)
1463 	{
1464 	int i,j;
1465 	void (*cb)(const SSL *ssl,int type,int val)=NULL;
1466 
1467 	s->s3->alert_dispatch=0;
1468 	i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1469 	if (i <= 0)
1470 		{
1471 		s->s3->alert_dispatch=1;
1472 		}
1473 	else
1474 		{
1475 		/* Alert sent to BIO.  If it is important, flush it now.
1476 		 * If the message does not get sent due to non-blocking IO,
1477 		 * we will not worry too much. */
1478 		if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1479 			(void)BIO_flush(s->wbio);
1480 
1481 		if (s->msg_callback)
1482 			s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1483 
1484 		if (s->info_callback != NULL)
1485 			cb=s->info_callback;
1486 		else if (s->ctx->info_callback != NULL)
1487 			cb=s->ctx->info_callback;
1488 
1489 		if (cb != NULL)
1490 			{
1491 			j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1492 			cb(s,SSL_CB_WRITE_ALERT,j);
1493 			}
1494 		}
1495 	return(i);
1496 	}
1497