s3_pkt.c revision 277195
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#include <openssl/rand.h>
119
120static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
121			 unsigned int len, int create_empty_fragment);
122static int ssl3_get_record(SSL *s);
123
124int ssl3_read_n(SSL *s, int n, int max, int extend)
125	{
126	/* If extend == 0, obtain new n-byte packet; if extend == 1, increase
127	 * packet by another n bytes.
128	 * The packet will be in the sub-array of s->s3->rbuf.buf specified
129	 * by s->packet and s->packet_length.
130	 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
131	 * [plus s->packet_length bytes if extend == 1].)
132	 */
133	int i,len,left;
134	long align=0;
135	unsigned char *pkt;
136	SSL3_BUFFER *rb;
137
138	if (n <= 0) return n;
139
140	rb    = &(s->s3->rbuf);
141	if (rb->buf == NULL)
142		if (!ssl3_setup_read_buffer(s))
143			return -1;
144
145	left  = rb->left;
146#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
147	align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
148	align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
149#endif
150
151	if (!extend)
152		{
153		/* start with empty packet ... */
154		if (left == 0)
155			rb->offset = align;
156		else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
157			{
158			/* check if next packet length is large
159			 * enough to justify payload alignment... */
160			pkt = rb->buf + rb->offset;
161			if (pkt[0] == SSL3_RT_APPLICATION_DATA
162			    && (pkt[3]<<8|pkt[4]) >= 128)
163				{
164				/* Note that even if packet is corrupted
165				 * and its length field is insane, we can
166				 * only be led to wrong decision about
167				 * whether memmove will occur or not.
168				 * Header values has no effect on memmove
169				 * arguments and therefore no buffer
170				 * overrun can be triggered. */
171				memmove (rb->buf+align,pkt,left);
172				rb->offset = align;
173				}
174			}
175		s->packet = rb->buf + rb->offset;
176		s->packet_length = 0;
177		/* ... now we can act as if 'extend' was set */
178		}
179
180	/* For DTLS/UDP reads should not span multiple packets
181	 * because the read operation returns the whole packet
182	 * at once (as long as it fits into the buffer). */
183	if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
184		{
185		if (left == 0 && extend)
186			return 0;
187		if (left > 0 && n > left)
188			n = left;
189		}
190
191	/* if there is enough in the buffer from a previous read, take some */
192	if (left >= n)
193		{
194		s->packet_length+=n;
195		rb->left=left-n;
196		rb->offset+=n;
197		return(n);
198		}
199
200	/* else we need to read more data */
201
202	len = s->packet_length;
203	pkt = rb->buf+align;
204	/* Move any available bytes to front of buffer:
205	 * 'len' bytes already pointed to by 'packet',
206	 * 'left' extra ones at the end */
207	if (s->packet != pkt) /* len > 0 */
208		{
209		memmove(pkt, s->packet, len+left);
210		s->packet = pkt;
211		rb->offset = len + align;
212		}
213
214	if (n > (int)(rb->len - rb->offset)) /* does not happen */
215		{
216		SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
217		return -1;
218		}
219
220	if (!s->read_ahead)
221		/* ignore max parameter */
222		max = n;
223	else
224		{
225		if (max < n)
226			max = n;
227		if (max > (int)(rb->len - rb->offset))
228			max = rb->len - rb->offset;
229		}
230
231	while (left < n)
232		{
233		/* Now we have len+left bytes at the front of s->s3->rbuf.buf
234		 * and need to read in more until we have len+n (up to
235		 * len+max if possible) */
236
237		clear_sys_error();
238		if (s->rbio != NULL)
239			{
240			s->rwstate=SSL_READING;
241			i=BIO_read(s->rbio,pkt+len+left, max-left);
242			}
243		else
244			{
245			SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
246			i = -1;
247			}
248
249		if (i <= 0)
250			{
251			rb->left = left;
252			if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
253			    SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
254				if (len+left == 0)
255					ssl3_release_read_buffer(s);
256			return(i);
257			}
258		left+=i;
259		/* reads should *never* span multiple packets for DTLS because
260		 * the underlying transport protocol is message oriented as opposed
261		 * to byte oriented as in the TLS case. */
262		if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
263			{
264			if (n > left)
265				n = left; /* makes the while condition false */
266			}
267		}
268
269	/* done reading, now the book-keeping */
270	rb->offset += n;
271	rb->left = left - n;
272	s->packet_length += n;
273	s->rwstate=SSL_NOTHING;
274	return(n);
275	}
276
277/* Call this to get a new input record.
278 * It will return <= 0 if more data is needed, normally due to an error
279 * or non-blocking IO.
280 * When it finishes, one packet has been decoded and can be found in
281 * ssl->s3->rrec.type    - is the type of record
282 * ssl->s3->rrec.data, 	 - data
283 * ssl->s3->rrec.length, - number of bytes
284 */
285/* used only by ssl3_read_bytes */
286static int ssl3_get_record(SSL *s)
287	{
288	int ssl_major,ssl_minor,al;
289	int enc_err,n,i,ret= -1;
290	SSL3_RECORD *rr;
291	SSL_SESSION *sess;
292	unsigned char *p;
293	unsigned char md[EVP_MAX_MD_SIZE];
294	short version;
295	unsigned mac_size, orig_len;
296	size_t extra;
297
298	rr= &(s->s3->rrec);
299	sess=s->session;
300
301	if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
302		extra=SSL3_RT_MAX_EXTRA;
303	else
304		extra=0;
305	if (extra && !s->s3->init_extra)
306		{
307		/* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
308		 * set after ssl3_setup_buffers() was done */
309		SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
310		return -1;
311		}
312
313again:
314	/* check if we have the header */
315	if (	(s->rstate != SSL_ST_READ_BODY) ||
316		(s->packet_length < SSL3_RT_HEADER_LENGTH))
317		{
318		n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
319		if (n <= 0) return(n); /* error or non-blocking */
320		s->rstate=SSL_ST_READ_BODY;
321
322		p=s->packet;
323
324		/* Pull apart the header into the SSL3_RECORD */
325		rr->type= *(p++);
326		ssl_major= *(p++);
327		ssl_minor= *(p++);
328		version=(ssl_major<<8)|ssl_minor;
329		n2s(p,rr->length);
330#if 0
331fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
332#endif
333
334		/* Lets check version */
335		if (!s->first_packet)
336			{
337			if (version != s->version)
338				{
339				SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
340                                if ((s->version & 0xFF00) == (version & 0xFF00))
341                                	/* Send back error using their minor version number :-) */
342					s->version = (unsigned short)version;
343				al=SSL_AD_PROTOCOL_VERSION;
344				goto f_err;
345				}
346			}
347
348		if ((version>>8) != SSL3_VERSION_MAJOR)
349			{
350			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
351			goto err;
352			}
353
354		if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
355			{
356			al=SSL_AD_RECORD_OVERFLOW;
357			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
358			goto f_err;
359			}
360
361		/* now s->rstate == SSL_ST_READ_BODY */
362		}
363
364	/* s->rstate == SSL_ST_READ_BODY, get and decode the data */
365
366	if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
367		{
368		/* now s->packet_length == SSL3_RT_HEADER_LENGTH */
369		i=rr->length;
370		n=ssl3_read_n(s,i,i,1);
371		if (n <= 0) return(n); /* error or non-blocking io */
372		/* now n == rr->length,
373		 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
374		}
375
376	s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
377
378	/* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
379	 * and we have that many bytes in s->packet
380	 */
381	rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
382
383	/* ok, we can now read from 's->packet' data into 'rr'
384	 * rr->input points at rr->length bytes, which
385	 * need to be copied into rr->data by either
386	 * the decryption or by the decompression
387	 * When the data is 'copied' into the rr->data buffer,
388	 * rr->input will be pointed at the new buffer */
389
390	/* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
391	 * rr->length bytes of encrypted compressed stuff. */
392
393	/* check is not needed I believe */
394	if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
395		{
396		al=SSL_AD_RECORD_OVERFLOW;
397		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
398		goto f_err;
399		}
400
401	/* decrypt in place in 'rr->input' */
402	rr->data=rr->input;
403
404	enc_err = s->method->ssl3_enc->enc(s,0);
405	/* enc_err is:
406	 *    0: (in non-constant time) if the record is publically invalid.
407	 *    1: if the padding is valid
408	 *    -1: if the padding is invalid */
409	if (enc_err == 0)
410		{
411		al=SSL_AD_DECRYPTION_FAILED;
412		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
413		goto f_err;
414		}
415
416#ifdef TLS_DEBUG
417printf("dec %d\n",rr->length);
418{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
419printf("\n");
420#endif
421
422	/* r->length is now the compressed data plus mac */
423	if ((sess != NULL) &&
424	    (s->enc_read_ctx != NULL) &&
425	    (EVP_MD_CTX_md(s->read_hash) != NULL))
426		{
427		/* s->read_hash != NULL => mac_size != -1 */
428		unsigned char *mac = NULL;
429		unsigned char mac_tmp[EVP_MAX_MD_SIZE];
430		mac_size=EVP_MD_CTX_size(s->read_hash);
431		OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
432
433		/* kludge: *_cbc_remove_padding passes padding length in rr->type */
434		orig_len = rr->length+((unsigned int)rr->type>>8);
435
436		/* orig_len is the length of the record before any padding was
437		 * removed. This is public information, as is the MAC in use,
438		 * therefore we can safely process the record in a different
439		 * amount of time if it's too short to possibly contain a MAC.
440		 */
441		if (orig_len < mac_size ||
442		    /* CBC records must have a padding length byte too. */
443		    (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
444		     orig_len < mac_size+1))
445			{
446			al=SSL_AD_DECODE_ERROR;
447			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
448			goto f_err;
449			}
450
451		if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
452			{
453			/* We update the length so that the TLS header bytes
454			 * can be constructed correctly but we need to extract
455			 * the MAC in constant time from within the record,
456			 * without leaking the contents of the padding bytes.
457			 * */
458			mac = mac_tmp;
459			ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
460			rr->length -= mac_size;
461			}
462		else
463			{
464			/* In this case there's no padding, so |orig_len|
465			 * equals |rec->length| and we checked that there's
466			 * enough bytes for |mac_size| above. */
467			rr->length -= mac_size;
468			mac = &rr->data[rr->length];
469			}
470
471		i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
472		if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
473			enc_err = -1;
474		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
475			enc_err = -1;
476		}
477
478	if (enc_err < 0)
479		{
480		/* A separate 'decryption_failed' alert was introduced with TLS 1.0,
481		 * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
482		 * failure is directly visible from the ciphertext anyway,
483		 * we should not reveal which kind of error occured -- this
484		 * might become visible to an attacker (e.g. via a logfile) */
485		al=SSL_AD_BAD_RECORD_MAC;
486		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
487		goto f_err;
488		}
489
490	/* r->length is now just compressed */
491	if (s->expand != NULL)
492		{
493		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
494			{
495			al=SSL_AD_RECORD_OVERFLOW;
496			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
497			goto f_err;
498			}
499		if (!ssl3_do_uncompress(s))
500			{
501			al=SSL_AD_DECOMPRESSION_FAILURE;
502			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
503			goto f_err;
504			}
505		}
506
507	if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
508		{
509		al=SSL_AD_RECORD_OVERFLOW;
510		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
511		goto f_err;
512		}
513
514	rr->off=0;
515	/* So at this point the following is true
516	 * ssl->s3->rrec.type 	is the type of record
517	 * ssl->s3->rrec.length	== number of bytes in record
518	 * ssl->s3->rrec.off	== offset to first valid byte
519	 * ssl->s3->rrec.data	== where to take bytes from, increment
520	 *			   after use :-).
521	 */
522
523	/* we have pulled in a full packet so zero things */
524	s->packet_length=0;
525
526	/* just read a 0 length packet */
527	if (rr->length == 0) goto again;
528
529#if 0
530fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
531#endif
532
533	return(1);
534
535f_err:
536	ssl3_send_alert(s,SSL3_AL_FATAL,al);
537err:
538	return(ret);
539	}
540
541int ssl3_do_uncompress(SSL *ssl)
542	{
543#ifndef OPENSSL_NO_COMP
544	int i;
545	SSL3_RECORD *rr;
546
547	rr= &(ssl->s3->rrec);
548	i=COMP_expand_block(ssl->expand,rr->comp,
549		SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
550	if (i < 0)
551		return(0);
552	else
553		rr->length=i;
554	rr->data=rr->comp;
555#endif
556	return(1);
557	}
558
559int ssl3_do_compress(SSL *ssl)
560	{
561#ifndef OPENSSL_NO_COMP
562	int i;
563	SSL3_RECORD *wr;
564
565	wr= &(ssl->s3->wrec);
566	i=COMP_compress_block(ssl->compress,wr->data,
567		SSL3_RT_MAX_COMPRESSED_LENGTH,
568		wr->input,(int)wr->length);
569	if (i < 0)
570		return(0);
571	else
572		wr->length=i;
573
574	wr->input=wr->data;
575#endif
576	return(1);
577	}
578
579/* Call this to write data in records of type 'type'
580 * It will return <= 0 if not all data has been sent or non-blocking IO.
581 */
582int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
583	{
584	const unsigned char *buf=buf_;
585	unsigned int tot,n,nw;
586	int i;
587
588	s->rwstate=SSL_NOTHING;
589	tot=s->s3->wnum;
590	s->s3->wnum=0;
591
592	if (SSL_in_init(s) && !s->in_handshake)
593		{
594		i=s->handshake_func(s);
595		if (i < 0) return(i);
596		if (i == 0)
597			{
598			SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
599			return -1;
600			}
601		}
602
603	n=(len-tot);
604	for (;;)
605		{
606		if (n > s->max_send_fragment)
607			nw=s->max_send_fragment;
608		else
609			nw=n;
610
611		i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
612		if (i <= 0)
613			{
614			s->s3->wnum=tot;
615			return i;
616			}
617
618		if ((i == (int)n) ||
619			(type == SSL3_RT_APPLICATION_DATA &&
620			 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
621			{
622			/* next chunk of data should get another prepended empty fragment
623			 * in ciphersuites with known-IV weakness: */
624			s->s3->empty_fragment_done = 0;
625
626			return tot+i;
627			}
628
629		n-=i;
630		tot+=i;
631		}
632	}
633
634static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
635			 unsigned int len, int create_empty_fragment)
636	{
637	unsigned char *p,*plen;
638	int i,mac_size,clear=0;
639	int prefix_len=0;
640	int eivlen;
641	long align=0;
642	SSL3_RECORD *wr;
643	SSL3_BUFFER *wb=&(s->s3->wbuf);
644	SSL_SESSION *sess;
645
646 	if (wb->buf == NULL)
647		if (!ssl3_setup_write_buffer(s))
648			return -1;
649
650	/* first check if there is a SSL3_BUFFER still being written
651	 * out.  This will happen with non blocking IO */
652	if (wb->left != 0)
653		return(ssl3_write_pending(s,type,buf,len));
654
655	/* If we have an alert to send, lets send it */
656	if (s->s3->alert_dispatch)
657		{
658		i=s->method->ssl_dispatch_alert(s);
659		if (i <= 0)
660			return(i);
661		/* if it went, fall through and send more stuff */
662		/* we may have released our buffer, so get it again */
663		if (wb->buf == NULL)
664			if (!ssl3_setup_write_buffer(s))
665				return -1;
666		}
667
668	if (len == 0 && !create_empty_fragment)
669		return 0;
670
671	wr= &(s->s3->wrec);
672	sess=s->session;
673
674	if (	(sess == NULL) ||
675		(s->enc_write_ctx == NULL) ||
676		(EVP_MD_CTX_md(s->write_hash) == NULL))
677		{
678#if 1
679		clear=s->enc_write_ctx?0:1;	/* must be AEAD cipher */
680#else
681		clear=1;
682#endif
683		mac_size=0;
684		}
685	else
686		{
687		mac_size=EVP_MD_CTX_size(s->write_hash);
688		if (mac_size < 0)
689			goto err;
690		}
691
692	/* 'create_empty_fragment' is true only when this function calls itself */
693	if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
694		{
695		/* countermeasure against known-IV weakness in CBC ciphersuites
696		 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
697
698		if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
699			{
700			/* recursive function call with 'create_empty_fragment' set;
701			 * this prepares and buffers the data for an empty fragment
702			 * (these 'prefix_len' bytes are sent out later
703			 * together with the actual payload) */
704			prefix_len = do_ssl3_write(s, type, buf, 0, 1);
705			if (prefix_len <= 0)
706				goto err;
707
708			if (prefix_len >
709		(SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
710				{
711				/* insufficient space */
712				SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
713				goto err;
714				}
715			}
716
717		s->s3->empty_fragment_done = 1;
718		}
719
720	if (create_empty_fragment)
721		{
722#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
723		/* extra fragment would be couple of cipher blocks,
724		 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
725		 * if we want to align the real payload, then we can
726		 * just pretent we simply have two headers. */
727		align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
728		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
729#endif
730		p = wb->buf + align;
731		wb->offset  = align;
732		}
733	else if (prefix_len)
734		{
735		p = wb->buf + wb->offset + prefix_len;
736		}
737	else
738		{
739#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
740		align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
741		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
742#endif
743		p = wb->buf + align;
744		wb->offset  = align;
745		}
746
747	/* write the header */
748
749	*(p++)=type&0xff;
750	wr->type=type;
751
752	*(p++)=(s->version>>8);
753	/* Some servers hang if iniatial client hello is larger than 256
754	 * bytes and record version number > TLS 1.0
755	 */
756	if (s->state == SSL3_ST_CW_CLNT_HELLO_B
757				&& !s->renegotiate
758				&& TLS1_get_version(s) > TLS1_VERSION)
759		*(p++) = 0x1;
760	else
761		*(p++)=s->version&0xff;
762
763	/* field where we are to write out packet length */
764	plen=p;
765	p+=2;
766	/* Explicit IV length, block ciphers and TLS version 1.1 or later */
767	if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
768		{
769		int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
770		if (mode == EVP_CIPH_CBC_MODE)
771			{
772			eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
773			if (eivlen <= 1)
774				eivlen = 0;
775			}
776		/* Need explicit part of IV for GCM mode */
777		else if (mode == EVP_CIPH_GCM_MODE)
778			eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
779		else
780			eivlen = 0;
781		}
782	else
783		eivlen = 0;
784
785	/* lets setup the record stuff. */
786	wr->data=p + eivlen;
787	wr->length=(int)len;
788	wr->input=(unsigned char *)buf;
789
790	/* we now 'read' from wr->input, wr->length bytes into
791	 * wr->data */
792
793	/* first we compress */
794	if (s->compress != NULL)
795		{
796		if (!ssl3_do_compress(s))
797			{
798			SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
799			goto err;
800			}
801		}
802	else
803		{
804		memcpy(wr->data,wr->input,wr->length);
805		wr->input=wr->data;
806		}
807
808	/* we should still have the output to wr->data and the input
809	 * from wr->input.  Length should be wr->length.
810	 * wr->data still points in the wb->buf */
811
812	if (mac_size != 0)
813		{
814		if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
815			goto err;
816		wr->length+=mac_size;
817		}
818
819	wr->input=p;
820	wr->data=p;
821
822	if (eivlen)
823		{
824	/*	if (RAND_pseudo_bytes(p, eivlen) <= 0)
825			goto err; */
826		wr->length += eivlen;
827		}
828
829	/* ssl3_enc can only have an error on read */
830	s->method->ssl3_enc->enc(s,1);
831
832	/* record length after mac and block padding */
833	s2n(wr->length,plen);
834
835	/* we should now have
836	 * wr->data pointing to the encrypted data, which is
837	 * wr->length long */
838	wr->type=type; /* not needed but helps for debugging */
839	wr->length+=SSL3_RT_HEADER_LENGTH;
840
841	if (create_empty_fragment)
842		{
843		/* we are in a recursive call;
844		 * just return the length, don't write out anything here
845		 */
846		return wr->length;
847		}
848
849	/* now let's set up wb */
850	wb->left = prefix_len + wr->length;
851
852	/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
853	s->s3->wpend_tot=len;
854	s->s3->wpend_buf=buf;
855	s->s3->wpend_type=type;
856	s->s3->wpend_ret=len;
857
858	/* we now just need to write the buffer */
859	return ssl3_write_pending(s,type,buf,len);
860err:
861	return -1;
862	}
863
864/* if s->s3->wbuf.left != 0, we need to call this */
865int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
866	unsigned int len)
867	{
868	int i;
869	SSL3_BUFFER *wb=&(s->s3->wbuf);
870
871/* XXXX */
872	if ((s->s3->wpend_tot > (int)len)
873		|| ((s->s3->wpend_buf != buf) &&
874			!(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
875		|| (s->s3->wpend_type != type))
876		{
877		SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
878		return(-1);
879		}
880
881	for (;;)
882		{
883		clear_sys_error();
884		if (s->wbio != NULL)
885			{
886			s->rwstate=SSL_WRITING;
887			i=BIO_write(s->wbio,
888				(char *)&(wb->buf[wb->offset]),
889				(unsigned int)wb->left);
890			}
891		else
892			{
893			SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
894			i= -1;
895			}
896		if (i == wb->left)
897			{
898			wb->left=0;
899			wb->offset+=i;
900			if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
901			    SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
902				ssl3_release_write_buffer(s);
903			s->rwstate=SSL_NOTHING;
904			return(s->s3->wpend_ret);
905			}
906		else if (i <= 0) {
907			if (s->version == DTLS1_VERSION ||
908			    s->version == DTLS1_BAD_VER) {
909				/* For DTLS, just drop it. That's kind of the whole
910				   point in using a datagram service */
911				wb->left = 0;
912			}
913			return(i);
914		}
915		wb->offset+=i;
916		wb->left-=i;
917		}
918	}
919
920/* Return up to 'len' payload bytes received in 'type' records.
921 * 'type' is one of the following:
922 *
923 *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
924 *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
925 *   -  0 (during a shutdown, no data has to be returned)
926 *
927 * If we don't have stored data to work from, read a SSL/TLS record first
928 * (possibly multiple records if we still don't have anything to return).
929 *
930 * This function must handle any surprises the peer may have for us, such as
931 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
932 * a surprise, but handled as if it were), or renegotiation requests.
933 * Also if record payloads contain fragments too small to process, we store
934 * them until there is enough for the respective protocol (the record protocol
935 * may use arbitrary fragmentation and even interleaving):
936 *     Change cipher spec protocol
937 *             just 1 byte needed, no need for keeping anything stored
938 *     Alert protocol
939 *             2 bytes needed (AlertLevel, AlertDescription)
940 *     Handshake protocol
941 *             4 bytes needed (HandshakeType, uint24 length) -- we just have
942 *             to detect unexpected Client Hello and Hello Request messages
943 *             here, anything else is handled by higher layers
944 *     Application data protocol
945 *             none of our business
946 */
947int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
948	{
949	int al,i,j,ret;
950	unsigned int n;
951	SSL3_RECORD *rr;
952	void (*cb)(const SSL *ssl,int type2,int val)=NULL;
953
954	if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
955		if (!ssl3_setup_read_buffer(s))
956			return(-1);
957
958	if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
959	    (peek && (type != SSL3_RT_APPLICATION_DATA)))
960		{
961		SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
962		return -1;
963		}
964
965	if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
966		/* (partially) satisfy request from storage */
967		{
968		unsigned char *src = s->s3->handshake_fragment;
969		unsigned char *dst = buf;
970		unsigned int k;
971
972		/* peek == 0 */
973		n = 0;
974		while ((len > 0) && (s->s3->handshake_fragment_len > 0))
975			{
976			*dst++ = *src++;
977			len--; s->s3->handshake_fragment_len--;
978			n++;
979			}
980		/* move any remaining fragment bytes: */
981		for (k = 0; k < s->s3->handshake_fragment_len; k++)
982			s->s3->handshake_fragment[k] = *src++;
983		return n;
984	}
985
986	/* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
987
988	if (!s->in_handshake && SSL_in_init(s))
989		{
990		/* type == SSL3_RT_APPLICATION_DATA */
991		i=s->handshake_func(s);
992		if (i < 0) return(i);
993		if (i == 0)
994			{
995			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
996			return(-1);
997			}
998		}
999start:
1000	s->rwstate=SSL_NOTHING;
1001
1002	/* s->s3->rrec.type	    - is the type of record
1003	 * s->s3->rrec.data,    - data
1004	 * s->s3->rrec.off,     - offset into 'data' for next read
1005	 * s->s3->rrec.length,  - number of bytes. */
1006	rr = &(s->s3->rrec);
1007
1008	/* get new packet if necessary */
1009	if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1010		{
1011		ret=ssl3_get_record(s);
1012		if (ret <= 0) return(ret);
1013		}
1014
1015	/* we now have a packet which can be read and processed */
1016
1017	if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1018	                               * reset by ssl3_get_finished */
1019		&& (rr->type != SSL3_RT_HANDSHAKE))
1020		{
1021		al=SSL_AD_UNEXPECTED_MESSAGE;
1022		SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1023		goto f_err;
1024		}
1025
1026	/* If the other end has shut down, throw anything we read away
1027	 * (even in 'peek' mode) */
1028	if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1029		{
1030		rr->length=0;
1031		s->rwstate=SSL_NOTHING;
1032		return(0);
1033		}
1034
1035
1036	if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1037		{
1038		/* make sure that we are not getting application data when we
1039		 * are doing a handshake for the first time */
1040		if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1041			(s->enc_read_ctx == NULL))
1042			{
1043			al=SSL_AD_UNEXPECTED_MESSAGE;
1044			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1045			goto f_err;
1046			}
1047
1048		if (len <= 0) return(len);
1049
1050		if ((unsigned int)len > rr->length)
1051			n = rr->length;
1052		else
1053			n = (unsigned int)len;
1054
1055		memcpy(buf,&(rr->data[rr->off]),n);
1056		if (!peek)
1057			{
1058			rr->length-=n;
1059			rr->off+=n;
1060			if (rr->length == 0)
1061				{
1062				s->rstate=SSL_ST_READ_HEADER;
1063				rr->off=0;
1064				if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0)
1065					ssl3_release_read_buffer(s);
1066				}
1067			}
1068		return(n);
1069		}
1070
1071
1072	/* If we get here, then type != rr->type; if we have a handshake
1073	 * message, then it was unexpected (Hello Request or Client Hello). */
1074
1075	/* In case of record types for which we have 'fragment' storage,
1076	 * fill that so that we can process the data at a fixed place.
1077	 */
1078		{
1079		unsigned int dest_maxlen = 0;
1080		unsigned char *dest = NULL;
1081		unsigned int *dest_len = NULL;
1082
1083		if (rr->type == SSL3_RT_HANDSHAKE)
1084			{
1085			dest_maxlen = sizeof s->s3->handshake_fragment;
1086			dest = s->s3->handshake_fragment;
1087			dest_len = &s->s3->handshake_fragment_len;
1088			}
1089		else if (rr->type == SSL3_RT_ALERT)
1090			{
1091			dest_maxlen = sizeof s->s3->alert_fragment;
1092			dest = s->s3->alert_fragment;
1093			dest_len = &s->s3->alert_fragment_len;
1094			}
1095#ifndef OPENSSL_NO_HEARTBEATS
1096		else if (rr->type == TLS1_RT_HEARTBEAT)
1097			{
1098			tls1_process_heartbeat(s);
1099
1100			/* Exit and notify application to read again */
1101			rr->length = 0;
1102			s->rwstate=SSL_READING;
1103			BIO_clear_retry_flags(SSL_get_rbio(s));
1104			BIO_set_retry_read(SSL_get_rbio(s));
1105			return(-1);
1106			}
1107#endif
1108
1109		if (dest_maxlen > 0)
1110			{
1111			n = dest_maxlen - *dest_len; /* available space in 'dest' */
1112			if (rr->length < n)
1113				n = rr->length; /* available bytes */
1114
1115			/* now move 'n' bytes: */
1116			while (n-- > 0)
1117				{
1118				dest[(*dest_len)++] = rr->data[rr->off++];
1119				rr->length--;
1120				}
1121
1122			if (*dest_len < dest_maxlen)
1123				goto start; /* fragment was too small */
1124			}
1125		}
1126
1127	/* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1128	 * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1129	 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1130
1131	/* If we are a client, check for an incoming 'Hello Request': */
1132	if ((!s->server) &&
1133		(s->s3->handshake_fragment_len >= 4) &&
1134		(s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1135		(s->session != NULL) && (s->session->cipher != NULL))
1136		{
1137		s->s3->handshake_fragment_len = 0;
1138
1139		if ((s->s3->handshake_fragment[1] != 0) ||
1140			(s->s3->handshake_fragment[2] != 0) ||
1141			(s->s3->handshake_fragment[3] != 0))
1142			{
1143			al=SSL_AD_DECODE_ERROR;
1144			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1145			goto f_err;
1146			}
1147
1148		if (s->msg_callback)
1149			s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1150
1151		if (SSL_is_init_finished(s) &&
1152			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1153			!s->s3->renegotiate)
1154			{
1155			ssl3_renegotiate(s);
1156			if (ssl3_renegotiate_check(s))
1157				{
1158				i=s->handshake_func(s);
1159				if (i < 0) return(i);
1160				if (i == 0)
1161					{
1162					SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1163					return(-1);
1164					}
1165
1166				if (!(s->mode & SSL_MODE_AUTO_RETRY))
1167					{
1168					if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1169						{
1170						BIO *bio;
1171						/* In the case where we try to read application data,
1172						 * but we trigger an SSL handshake, we return -1 with
1173						 * the retry option set.  Otherwise renegotiation may
1174						 * cause nasty problems in the blocking world */
1175						s->rwstate=SSL_READING;
1176						bio=SSL_get_rbio(s);
1177						BIO_clear_retry_flags(bio);
1178						BIO_set_retry_read(bio);
1179						return(-1);
1180						}
1181					}
1182				}
1183			}
1184		/* we either finished a handshake or ignored the request,
1185		 * now try again to obtain the (application) data we were asked for */
1186		goto start;
1187		}
1188	/* If we are a server and get a client hello when renegotiation isn't
1189	 * allowed send back a no renegotiation alert and carry on.
1190	 * WARNING: experimental code, needs reviewing (steve)
1191	 */
1192	if (s->server &&
1193		SSL_is_init_finished(s) &&
1194    		!s->s3->send_connection_binding &&
1195		(s->version > SSL3_VERSION) &&
1196		(s->s3->handshake_fragment_len >= 4) &&
1197		(s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1198		(s->session != NULL) && (s->session->cipher != NULL) &&
1199		!(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1200
1201		{
1202		/*s->s3->handshake_fragment_len = 0;*/
1203		rr->length = 0;
1204		ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1205		goto start;
1206		}
1207	if (s->s3->alert_fragment_len >= 2)
1208		{
1209		int alert_level = s->s3->alert_fragment[0];
1210		int alert_descr = s->s3->alert_fragment[1];
1211
1212		s->s3->alert_fragment_len = 0;
1213
1214		if (s->msg_callback)
1215			s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1216
1217		if (s->info_callback != NULL)
1218			cb=s->info_callback;
1219		else if (s->ctx->info_callback != NULL)
1220			cb=s->ctx->info_callback;
1221
1222		if (cb != NULL)
1223			{
1224			j = (alert_level << 8) | alert_descr;
1225			cb(s, SSL_CB_READ_ALERT, j);
1226			}
1227
1228		if (alert_level == 1) /* warning */
1229			{
1230			s->s3->warn_alert = alert_descr;
1231			if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1232				{
1233				s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1234				return(0);
1235				}
1236			/* This is a warning but we receive it if we requested
1237			 * renegotiation and the peer denied it. Terminate with
1238			 * a fatal alert because if application tried to
1239			 * renegotiatie it presumably had a good reason and
1240			 * expects it to succeed.
1241			 *
1242			 * In future we might have a renegotiation where we
1243			 * don't care if the peer refused it where we carry on.
1244			 */
1245			else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1246				{
1247				al = SSL_AD_HANDSHAKE_FAILURE;
1248				SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1249				goto f_err;
1250				}
1251#ifdef SSL_AD_MISSING_SRP_USERNAME
1252			else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1253				return(0);
1254#endif
1255			}
1256		else if (alert_level == 2) /* fatal */
1257			{
1258			char tmp[16];
1259
1260			s->rwstate=SSL_NOTHING;
1261			s->s3->fatal_alert = alert_descr;
1262			SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1263			BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1264			ERR_add_error_data(2,"SSL alert number ",tmp);
1265			s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1266			SSL_CTX_remove_session(s->ctx,s->session);
1267			return(0);
1268			}
1269		else
1270			{
1271			al=SSL_AD_ILLEGAL_PARAMETER;
1272			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1273			goto f_err;
1274			}
1275
1276		goto start;
1277		}
1278
1279	if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1280		{
1281		s->rwstate=SSL_NOTHING;
1282		rr->length=0;
1283		return(0);
1284		}
1285
1286	if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1287		{
1288		/* 'Change Cipher Spec' is just a single byte, so we know
1289		 * exactly what the record payload has to look like */
1290		if (	(rr->length != 1) || (rr->off != 0) ||
1291			(rr->data[0] != SSL3_MT_CCS))
1292			{
1293			al=SSL_AD_ILLEGAL_PARAMETER;
1294			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1295			goto f_err;
1296			}
1297
1298		/* Check we have a cipher to change to */
1299		if (s->s3->tmp.new_cipher == NULL)
1300			{
1301			al=SSL_AD_UNEXPECTED_MESSAGE;
1302			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1303			goto f_err;
1304			}
1305
1306		if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1307			{
1308			al=SSL_AD_UNEXPECTED_MESSAGE;
1309			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1310			goto f_err;
1311			}
1312
1313		s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1314
1315		rr->length=0;
1316
1317		if (s->msg_callback)
1318			s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1319
1320		s->s3->change_cipher_spec=1;
1321		if (!ssl3_do_change_cipher_spec(s))
1322			goto err;
1323		else
1324			goto start;
1325		}
1326
1327	/* Unexpected handshake message (Client Hello, or protocol violation) */
1328	if ((s->s3->handshake_fragment_len >= 4) &&	!s->in_handshake)
1329		{
1330		if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1331			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1332			{
1333#if 0 /* worked only because C operator preferences are not as expected (and
1334       * because this is not really needed for clients except for detecting
1335       * protocol violations): */
1336			s->state=SSL_ST_BEFORE|(s->server)
1337				?SSL_ST_ACCEPT
1338				:SSL_ST_CONNECT;
1339#else
1340			s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1341#endif
1342			s->renegotiate=1;
1343			s->new_session=1;
1344			}
1345		i=s->handshake_func(s);
1346		if (i < 0) return(i);
1347		if (i == 0)
1348			{
1349			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1350			return(-1);
1351			}
1352
1353		if (!(s->mode & SSL_MODE_AUTO_RETRY))
1354			{
1355			if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1356				{
1357				BIO *bio;
1358				/* In the case where we try to read application data,
1359				 * but we trigger an SSL handshake, we return -1 with
1360				 * the retry option set.  Otherwise renegotiation may
1361				 * cause nasty problems in the blocking world */
1362				s->rwstate=SSL_READING;
1363				bio=SSL_get_rbio(s);
1364				BIO_clear_retry_flags(bio);
1365				BIO_set_retry_read(bio);
1366				return(-1);
1367				}
1368			}
1369		goto start;
1370		}
1371
1372	switch (rr->type)
1373		{
1374	default:
1375#ifndef OPENSSL_NO_TLS
1376		/* TLS up to v1.1 just ignores unknown message types:
1377		 * TLS v1.2 give an unexpected message alert.
1378		 */
1379		if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1380			{
1381			rr->length = 0;
1382			goto start;
1383			}
1384#endif
1385		al=SSL_AD_UNEXPECTED_MESSAGE;
1386		SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1387		goto f_err;
1388	case SSL3_RT_CHANGE_CIPHER_SPEC:
1389	case SSL3_RT_ALERT:
1390	case SSL3_RT_HANDSHAKE:
1391		/* we already handled all of these, with the possible exception
1392		 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1393		 * should not happen when type != rr->type */
1394		al=SSL_AD_UNEXPECTED_MESSAGE;
1395		SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1396		goto f_err;
1397	case SSL3_RT_APPLICATION_DATA:
1398		/* At this point, we were expecting handshake data,
1399		 * but have application data.  If the library was
1400		 * running inside ssl3_read() (i.e. in_read_app_data
1401		 * is set) and it makes sense to read application data
1402		 * at this point (session renegotiation not yet started),
1403		 * we will indulge it.
1404		 */
1405		if (s->s3->in_read_app_data &&
1406			(s->s3->total_renegotiations != 0) &&
1407			((
1408				(s->state & SSL_ST_CONNECT) &&
1409				(s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1410				(s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1411				) || (
1412					(s->state & SSL_ST_ACCEPT) &&
1413					(s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1414					(s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1415					)
1416				))
1417			{
1418			s->s3->in_read_app_data=2;
1419			return(-1);
1420			}
1421		else
1422			{
1423			al=SSL_AD_UNEXPECTED_MESSAGE;
1424			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1425			goto f_err;
1426			}
1427		}
1428	/* not reached */
1429
1430f_err:
1431	ssl3_send_alert(s,SSL3_AL_FATAL,al);
1432err:
1433	return(-1);
1434	}
1435
1436int ssl3_do_change_cipher_spec(SSL *s)
1437	{
1438	int i;
1439	const char *sender;
1440	int slen;
1441
1442	if (s->state & SSL_ST_ACCEPT)
1443		i=SSL3_CHANGE_CIPHER_SERVER_READ;
1444	else
1445		i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1446
1447	if (s->s3->tmp.key_block == NULL)
1448		{
1449		if (s->session == NULL || s->session->master_key_length == 0)
1450			{
1451			/* might happen if dtls1_read_bytes() calls this */
1452			SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1453			return (0);
1454			}
1455
1456		s->session->cipher=s->s3->tmp.new_cipher;
1457		if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1458		}
1459
1460	if (!s->method->ssl3_enc->change_cipher_state(s,i))
1461		return(0);
1462
1463	/* we have to record the message digest at
1464	 * this point so we can get it before we read
1465	 * the finished message */
1466	if (s->state & SSL_ST_CONNECT)
1467		{
1468		sender=s->method->ssl3_enc->server_finished_label;
1469		slen=s->method->ssl3_enc->server_finished_label_len;
1470		}
1471	else
1472		{
1473		sender=s->method->ssl3_enc->client_finished_label;
1474		slen=s->method->ssl3_enc->client_finished_label_len;
1475		}
1476
1477	s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1478		sender,slen,s->s3->tmp.peer_finish_md);
1479
1480	return(1);
1481	}
1482
1483int ssl3_send_alert(SSL *s, int level, int desc)
1484	{
1485	/* Map tls/ssl alert value to correct one */
1486	desc=s->method->ssl3_enc->alert_value(desc);
1487	if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1488		desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1489	if (desc < 0) return -1;
1490	/* If a fatal one, remove from cache */
1491	if ((level == 2) && (s->session != NULL))
1492		SSL_CTX_remove_session(s->ctx,s->session);
1493
1494	s->s3->alert_dispatch=1;
1495	s->s3->send_alert[0]=level;
1496	s->s3->send_alert[1]=desc;
1497	if (s->s3->wbuf.left == 0) /* data still being written out? */
1498		return s->method->ssl_dispatch_alert(s);
1499	/* else data is still being written out, we will get written
1500	 * some time in the future */
1501	return -1;
1502	}
1503
1504int ssl3_dispatch_alert(SSL *s)
1505	{
1506	int i,j;
1507	void (*cb)(const SSL *ssl,int type,int val)=NULL;
1508
1509	s->s3->alert_dispatch=0;
1510	i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1511	if (i <= 0)
1512		{
1513		s->s3->alert_dispatch=1;
1514		}
1515	else
1516		{
1517		/* Alert sent to BIO.  If it is important, flush it now.
1518		 * If the message does not get sent due to non-blocking IO,
1519		 * we will not worry too much. */
1520		if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1521			(void)BIO_flush(s->wbio);
1522
1523		if (s->msg_callback)
1524			s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1525
1526		if (s->info_callback != NULL)
1527			cb=s->info_callback;
1528		else if (s->ctx->info_callback != NULL)
1529			cb=s->ctx->info_callback;
1530
1531		if (cb != NULL)
1532			{
1533			j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1534			cb(s,SSL_CB_WRITE_ALERT,j);
1535			}
1536		}
1537	return(i);
1538	}
1539