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 && n > left)
186			n = left;
187		}
188
189	/* if there is enough in the buffer from a previous read, take some */
190	if (left >= n)
191		{
192		s->packet_length+=n;
193		rb->left=left-n;
194		rb->offset+=n;
195		return(n);
196		}
197
198	/* else we need to read more data */
199
200	len = s->packet_length;
201	pkt = rb->buf+align;
202	/* Move any available bytes to front of buffer:
203	 * 'len' bytes already pointed to by 'packet',
204	 * 'left' extra ones at the end */
205	if (s->packet != pkt) /* len > 0 */
206		{
207		memmove(pkt, s->packet, len+left);
208		s->packet = pkt;
209		rb->offset = len + align;
210		}
211
212	if (n > (int)(rb->len - rb->offset)) /* does not happen */
213		{
214		SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
215		return -1;
216		}
217
218	if (!s->read_ahead)
219		/* ignore max parameter */
220		max = n;
221	else
222		{
223		if (max < n)
224			max = n;
225		if (max > (int)(rb->len - rb->offset))
226			max = rb->len - rb->offset;
227		}
228
229	while (left < n)
230		{
231		/* Now we have len+left bytes at the front of s->s3->rbuf.buf
232		 * and need to read in more until we have len+n (up to
233		 * len+max if possible) */
234
235		clear_sys_error();
236		if (s->rbio != NULL)
237			{
238			s->rwstate=SSL_READING;
239			i=BIO_read(s->rbio,pkt+len+left, max-left);
240			}
241		else
242			{
243			SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
244			i = -1;
245			}
246
247		if (i <= 0)
248			{
249			rb->left = left;
250			if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
251			    SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
252				if (len+left == 0)
253					ssl3_release_read_buffer(s);
254			return(i);
255			}
256		left+=i;
257		/* reads should *never* span multiple packets for DTLS because
258		 * the underlying transport protocol is message oriented as opposed
259		 * to byte oriented as in the TLS case. */
260		if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
261			{
262			if (n > left)
263				n = left; /* makes the while condition false */
264			}
265		}
266
267	/* done reading, now the book-keeping */
268	rb->offset += n;
269	rb->left = left - n;
270	s->packet_length += n;
271	s->rwstate=SSL_NOTHING;
272	return(n);
273	}
274
275/* Call this to get a new input record.
276 * It will return <= 0 if more data is needed, normally due to an error
277 * or non-blocking IO.
278 * When it finishes, one packet has been decoded and can be found in
279 * ssl->s3->rrec.type    - is the type of record
280 * ssl->s3->rrec.data, 	 - data
281 * ssl->s3->rrec.length, - number of bytes
282 */
283/* used only by ssl3_read_bytes */
284static int ssl3_get_record(SSL *s)
285	{
286	int ssl_major,ssl_minor,al;
287	int enc_err,n,i,ret= -1;
288	SSL3_RECORD *rr;
289	SSL_SESSION *sess;
290	unsigned char *p;
291	unsigned char md[EVP_MAX_MD_SIZE];
292	short version;
293	int mac_size;
294	int clear=0;
295	size_t extra;
296	int decryption_failed_or_bad_record_mac = 0;
297	unsigned char *mac = NULL;
298#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
299	long align=SSL3_ALIGN_PAYLOAD;
300#else
301	long align=0;
302#endif
303
304	rr= &(s->s3->rrec);
305	sess=s->session;
306
307	if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
308		extra=SSL3_RT_MAX_EXTRA;
309	else
310		extra=0;
311	if (!(SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS) &&
312		extra && !s->s3->init_extra)
313		{
314		/* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
315		 * set after ssl3_setup_buffers() was done */
316		SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
317		return -1;
318		}
319
320again:
321	/* check if we have the header */
322	if (	(s->rstate != SSL_ST_READ_BODY) ||
323		(s->packet_length < SSL3_RT_HEADER_LENGTH))
324		{
325		n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
326		if (n <= 0) return(n); /* error or non-blocking */
327		s->rstate=SSL_ST_READ_BODY;
328
329		p=s->packet;
330
331		/* Pull apart the header into the SSL3_RECORD */
332		rr->type= *(p++);
333		ssl_major= *(p++);
334		ssl_minor= *(p++);
335		version=(ssl_major<<8)|ssl_minor;
336		n2s(p,rr->length);
337#if 0
338fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
339#endif
340
341		/* Lets check version */
342		if (!s->first_packet)
343			{
344			if (version != s->version)
345				{
346				SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
347                                if ((s->version & 0xFF00) == (version & 0xFF00))
348                                	/* Send back error using their minor version number :-) */
349					s->version = (unsigned short)version;
350				al=SSL_AD_PROTOCOL_VERSION;
351				goto f_err;
352				}
353			}
354
355		if ((version>>8) != SSL3_VERSION_MAJOR)
356			{
357			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
358			goto err;
359			}
360
361		/* If we receive a valid record larger than the current buffer size,
362		 * allocate some memory for it.
363		 */
364		if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH - align)
365			{
366			if ((p=OPENSSL_realloc(s->s3->rbuf.buf, rr->length + SSL3_RT_HEADER_LENGTH + align))==NULL)
367				{
368				SSLerr(SSL_F_SSL3_GET_RECORD,ERR_R_MALLOC_FAILURE);
369				goto err;
370				}
371			s->s3->rbuf.buf=p;
372			s->s3->rbuf.len=rr->length + SSL3_RT_HEADER_LENGTH + align;
373			s->packet= &(s->s3->rbuf.buf[0]);
374			}
375
376		if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
377			{
378			al=SSL_AD_RECORD_OVERFLOW;
379			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
380			goto f_err;
381			}
382
383		/* now s->rstate == SSL_ST_READ_BODY */
384		}
385
386	/* s->rstate == SSL_ST_READ_BODY, get and decode the data */
387
388	if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
389		{
390		/* now s->packet_length == SSL3_RT_HEADER_LENGTH */
391		i=rr->length;
392		n=ssl3_read_n(s,i,i,1);
393		if (n <= 0) return(n); /* error or non-blocking io */
394		/* now n == rr->length,
395		 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
396		}
397
398	s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
399
400	/* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
401	 * and we have that many bytes in s->packet
402	 */
403	rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
404
405	/* ok, we can now read from 's->packet' data into 'rr'
406	 * rr->input points at rr->length bytes, which
407	 * need to be copied into rr->data by either
408	 * the decryption or by the decompression
409	 * When the data is 'copied' into the rr->data buffer,
410	 * rr->input will be pointed at the new buffer */
411
412	/* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
413	 * rr->length bytes of encrypted compressed stuff. */
414
415	/* check is not needed I believe */
416	if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
417		{
418		al=SSL_AD_RECORD_OVERFLOW;
419		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
420		goto f_err;
421		}
422
423	/* decrypt in place in 'rr->input' */
424	rr->data=rr->input;
425
426	enc_err = s->method->ssl3_enc->enc(s,0);
427	if (enc_err <= 0)
428		{
429		if (enc_err == 0)
430			/* SSLerr() and ssl3_send_alert() have been called */
431			goto err;
432
433		/* Otherwise enc_err == -1, which indicates bad padding
434		 * (rec->length has not been changed in this case).
435		 * To minimize information leaked via timing, we will perform
436		 * the MAC computation anyway. */
437		decryption_failed_or_bad_record_mac = 1;
438		}
439
440#ifdef TLS_DEBUG
441printf("dec %d\n",rr->length);
442{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
443printf("\n");
444#endif
445
446	/* r->length is now the compressed data plus mac */
447	if (	(sess == NULL) ||
448		(s->enc_read_ctx == NULL) ||
449		(EVP_MD_CTX_md(s->read_hash) == NULL))
450		clear=1;
451
452	if (!clear)
453		{
454		/* !clear => s->read_hash != NULL => mac_size != -1 */
455		mac_size=EVP_MD_CTX_size(s->read_hash);
456		OPENSSL_assert(mac_size >= 0);
457
458		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
459			{
460#if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
461			al=SSL_AD_RECORD_OVERFLOW;
462			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
463			goto f_err;
464#else
465			decryption_failed_or_bad_record_mac = 1;
466#endif
467			}
468		/* check the MAC for rr->input (it's in mac_size bytes at the tail) */
469		if (rr->length >= (unsigned int)mac_size)
470			{
471			rr->length -= mac_size;
472			mac = &rr->data[rr->length];
473			}
474		else
475			{
476			/* record (minus padding) is too short to contain a MAC */
477#if 0 /* OK only for stream ciphers */
478			al=SSL_AD_DECODE_ERROR;
479			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
480			goto f_err;
481#else
482			decryption_failed_or_bad_record_mac = 1;
483			rr->length = 0;
484#endif
485			}
486		i=s->method->ssl3_enc->mac(s,md,0);
487		if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0)
488			{
489			decryption_failed_or_bad_record_mac = 1;
490			}
491		}
492
493	if (decryption_failed_or_bad_record_mac)
494		{
495		/* A separate 'decryption_failed' alert was introduced with TLS 1.0,
496		 * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
497		 * failure is directly visible from the ciphertext anyway,
498		 * we should not reveal which kind of error occured -- this
499		 * might become visible to an attacker (e.g. via a logfile) */
500		al=SSL_AD_BAD_RECORD_MAC;
501		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
502		goto f_err;
503		}
504
505	/* r->length is now just compressed */
506	if (s->expand != NULL)
507		{
508		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
509			{
510			al=SSL_AD_RECORD_OVERFLOW;
511			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
512			goto f_err;
513			}
514		if (!ssl3_do_uncompress(s))
515			{
516			al=SSL_AD_DECOMPRESSION_FAILURE;
517			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
518			goto f_err;
519			}
520		}
521
522	if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
523		{
524		al=SSL_AD_RECORD_OVERFLOW;
525		SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
526		goto f_err;
527		}
528
529	rr->off=0;
530	/* So at this point the following is true
531	 * ssl->s3->rrec.type 	is the type of record
532	 * ssl->s3->rrec.length	== number of bytes in record
533	 * ssl->s3->rrec.off	== offset to first valid byte
534	 * ssl->s3->rrec.data	== where to take bytes from, increment
535	 *			   after use :-).
536	 */
537
538	/* we have pulled in a full packet so zero things */
539	s->packet_length=0;
540
541	/* just read a 0 length packet */
542	if (rr->length == 0) goto again;
543
544#if 0
545fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
546#endif
547
548	return(1);
549
550f_err:
551	ssl3_send_alert(s,SSL3_AL_FATAL,al);
552err:
553	return(ret);
554	}
555
556int ssl3_do_uncompress(SSL *ssl)
557	{
558#ifndef OPENSSL_NO_COMP
559	int i;
560	SSL3_RECORD *rr;
561
562	rr= &(ssl->s3->rrec);
563	i=COMP_expand_block(ssl->expand,rr->comp,
564		SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
565	if (i < 0)
566		return(0);
567	else
568		rr->length=i;
569	rr->data=rr->comp;
570#endif
571	return(1);
572	}
573
574int ssl3_do_compress(SSL *ssl)
575	{
576#ifndef OPENSSL_NO_COMP
577	int i;
578	SSL3_RECORD *wr;
579
580	wr= &(ssl->s3->wrec);
581	i=COMP_compress_block(ssl->compress,wr->data,
582		SSL3_RT_MAX_COMPRESSED_LENGTH,
583		wr->input,(int)wr->length);
584	if (i < 0)
585		return(0);
586	else
587		wr->length=i;
588
589	wr->input=wr->data;
590#endif
591	return(1);
592	}
593
594/* Call this to write data in records of type 'type'
595 * It will return <= 0 if not all data has been sent or non-blocking IO.
596 */
597int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
598	{
599	const unsigned char *buf=buf_;
600	unsigned int tot,n,nw;
601	int i;
602	unsigned int max_plain_length;
603
604	s->rwstate=SSL_NOTHING;
605	tot=s->s3->wnum;
606	s->s3->wnum=0;
607
608	if (SSL_in_init(s) && !s->in_handshake)
609		{
610		i=s->handshake_func(s);
611		if (i < 0) return(i);
612		if (i == 0)
613			{
614			SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
615			return -1;
616			}
617		}
618
619	n=(len-tot);
620	for (;;)
621		{
622		if (type == SSL3_RT_APPLICATION_DATA && (SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS))
623			max_plain_length = SSL3_RT_DEFAULT_PLAIN_LENGTH;
624		else
625			max_plain_length = s->max_send_fragment;
626
627		if (n > max_plain_length)
628			nw = max_plain_length;
629		else
630			nw=n;
631
632		i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
633		if (i <= 0)
634			{
635			s->s3->wnum=tot;
636			return i;
637			}
638
639		if ((i == (int)n) ||
640			(type == SSL3_RT_APPLICATION_DATA &&
641			 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
642			{
643			/* next chunk of data should get another prepended empty fragment
644			 * in ciphersuites with known-IV weakness: */
645			s->s3->empty_fragment_done = 0;
646
647			return tot+i;
648			}
649
650		n-=i;
651		tot+=i;
652		}
653	}
654
655static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
656			 unsigned int len, int create_empty_fragment)
657	{
658	unsigned char *p,*plen;
659	int i,mac_size,clear=0;
660	int prefix_len=0;
661	int eivlen;
662	long align=0;
663	SSL3_RECORD *wr;
664	SSL3_BUFFER *wb=&(s->s3->wbuf);
665	SSL_SESSION *sess;
666
667 	if (wb->buf == NULL)
668		if (!ssl3_setup_write_buffer(s))
669			return -1;
670
671	/* first check if there is a SSL3_BUFFER still being written
672	 * out.  This will happen with non blocking IO */
673	if (wb->left != 0)
674		return(ssl3_write_pending(s,type,buf,len));
675
676	/* If we have an alert to send, lets send it */
677	if (s->s3->alert_dispatch)
678		{
679		i=s->method->ssl_dispatch_alert(s);
680		if (i <= 0)
681			return(i);
682		/* if it went, fall through and send more stuff */
683		}
684
685	if (len == 0 && !create_empty_fragment)
686		return 0;
687
688	wr= &(s->s3->wrec);
689	sess=s->session;
690
691	if (	(sess == NULL) ||
692		(s->enc_write_ctx == NULL) ||
693		(EVP_MD_CTX_md(s->write_hash) == NULL))
694		{
695#if 1
696		clear=s->enc_write_ctx?0:1;	/* must be AEAD cipher */
697#else
698		clear=1;
699#endif
700		mac_size=0;
701		}
702	else
703		{
704		mac_size=EVP_MD_CTX_size(s->write_hash);
705		if (mac_size < 0)
706			goto err;
707		}
708
709	/* 'create_empty_fragment' is true only when this function calls itself */
710	if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
711		{
712		/* countermeasure against known-IV weakness in CBC ciphersuites
713		 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
714
715		if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
716			{
717			/* recursive function call with 'create_empty_fragment' set;
718			 * this prepares and buffers the data for an empty fragment
719			 * (these 'prefix_len' bytes are sent out later
720			 * together with the actual payload) */
721			prefix_len = do_ssl3_write(s, type, buf, 0, 1);
722			if (prefix_len <= 0)
723				goto err;
724
725			if (prefix_len >
726		(SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
727				{
728				/* insufficient space */
729				SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
730				goto err;
731				}
732			}
733
734		s->s3->empty_fragment_done = 1;
735		}
736
737	/* resize if necessary to hold the data. */
738	if (len + SSL3_RT_DEFAULT_WRITE_OVERHEAD > wb->len)
739		{
740		if ((p=OPENSSL_realloc(wb->buf, len + SSL3_RT_DEFAULT_WRITE_OVERHEAD))==NULL)
741			{
742			SSLerr(SSL_F_DO_SSL3_WRITE,ERR_R_MALLOC_FAILURE);
743			goto err;
744			}
745		wb->buf = p;
746		wb->len = len + SSL3_RT_DEFAULT_WRITE_OVERHEAD;
747		}
748
749	if (create_empty_fragment)
750		{
751#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
752		/* extra fragment would be couple of cipher blocks,
753		 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
754		 * if we want to align the real payload, then we can
755		 * just pretent we simply have two headers. */
756		align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
757		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
758#endif
759		p = wb->buf + align;
760		wb->offset  = align;
761		}
762	else if (prefix_len)
763		{
764		p = wb->buf + wb->offset + prefix_len;
765		}
766	else
767		{
768#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
769		align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
770		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
771#endif
772		p = wb->buf + align;
773		wb->offset  = align;
774		}
775
776	/* write the header */
777
778	*(p++)=type&0xff;
779	wr->type=type;
780
781	*(p++)=(s->version>>8);
782	/* Some servers hang if iniatial client hello is larger than 256
783	 * bytes and record version number > TLS 1.0
784	 */
785	if (s->state == SSL3_ST_CW_CLNT_HELLO_B
786				&& TLS1_get_version(s) > TLS1_VERSION)
787		*(p++) = 0x1;
788	else
789		*(p++)=s->version&0xff;
790
791	/* field where we are to write out packet length */
792	plen=p;
793	p+=2;
794	/* Explicit IV length, block ciphers and TLS version 1.1 or later */
795	if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
796		{
797		int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
798		if (mode == EVP_CIPH_CBC_MODE)
799			{
800			eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
801			if (eivlen <= 1)
802				eivlen = 0;
803			}
804		/* Need explicit part of IV for GCM mode */
805		else if (mode == EVP_CIPH_GCM_MODE)
806			eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
807		else
808			eivlen = 0;
809		}
810	else
811		eivlen = 0;
812
813	/* lets setup the record stuff. */
814	wr->data=p + eivlen;
815	wr->length=(int)len;
816	wr->input=(unsigned char *)buf;
817
818	/* we now 'read' from wr->input, wr->length bytes into
819	 * wr->data */
820
821	/* first we compress */
822	if (s->compress != NULL)
823		{
824		if (!ssl3_do_compress(s))
825			{
826			SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
827			goto err;
828			}
829		}
830	else
831		{
832		memcpy(wr->data,wr->input,wr->length);
833		wr->input=wr->data;
834		}
835
836	/* we should still have the output to wr->data and the input
837	 * from wr->input.  Length should be wr->length.
838	 * wr->data still points in the wb->buf */
839
840	if (mac_size != 0)
841		{
842		if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
843			goto err;
844		wr->length+=mac_size;
845		}
846
847	wr->input=p;
848	wr->data=p;
849
850	if (eivlen)
851		{
852	/*	if (RAND_pseudo_bytes(p, eivlen) <= 0)
853			goto err; */
854		wr->length += eivlen;
855		}
856
857	/* ssl3_enc can only have an error on read */
858	s->method->ssl3_enc->enc(s,1);
859
860	/* record length after mac and block padding */
861	s2n(wr->length,plen);
862
863	/* we should now have
864	 * wr->data pointing to the encrypted data, which is
865	 * wr->length long */
866	wr->type=type; /* not needed but helps for debugging */
867	wr->length+=SSL3_RT_HEADER_LENGTH;
868
869	if (create_empty_fragment)
870		{
871		/* we are in a recursive call;
872		 * just return the length, don't write out anything here
873		 */
874		return wr->length;
875		}
876
877	/* now let's set up wb */
878	wb->left = prefix_len + wr->length;
879
880	/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
881	s->s3->wpend_tot=len;
882	s->s3->wpend_buf=buf;
883	s->s3->wpend_type=type;
884	s->s3->wpend_ret=len;
885
886	/* we now just need to write the buffer */
887	return ssl3_write_pending(s,type,buf,len);
888err:
889	return -1;
890	}
891
892/* if s->s3->wbuf.left != 0, we need to call this */
893int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
894	unsigned int len)
895	{
896	int i;
897	SSL3_BUFFER *wb=&(s->s3->wbuf);
898
899/* XXXX */
900	if ((s->s3->wpend_tot > (int)len)
901		|| ((s->s3->wpend_buf != buf) &&
902			!(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
903		|| (s->s3->wpend_type != type))
904		{
905		SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
906		return(-1);
907		}
908
909	for (;;)
910		{
911		clear_sys_error();
912		if (s->wbio != NULL)
913			{
914			s->rwstate=SSL_WRITING;
915			i=BIO_write(s->wbio,
916				(char *)&(wb->buf[wb->offset]),
917				(unsigned int)wb->left);
918			}
919		else
920			{
921			SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
922			i= -1;
923			}
924		if (i == wb->left)
925			{
926			wb->left=0;
927			wb->offset+=i;
928			if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
929			    SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
930				ssl3_release_write_buffer(s);
931			s->rwstate=SSL_NOTHING;
932			return(s->s3->wpend_ret);
933			}
934		else if (i <= 0) {
935			if (s->version == DTLS1_VERSION ||
936			    s->version == DTLS1_BAD_VER) {
937				/* For DTLS, just drop it. That's kind of the whole
938				   point in using a datagram service */
939				wb->left = 0;
940			}
941			return(i);
942		}
943		wb->offset+=i;
944		wb->left-=i;
945		}
946	}
947
948/* Return up to 'len' payload bytes received in 'type' records.
949 * 'type' is one of the following:
950 *
951 *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
952 *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
953 *   -  0 (during a shutdown, no data has to be returned)
954 *
955 * If we don't have stored data to work from, read a SSL/TLS record first
956 * (possibly multiple records if we still don't have anything to return).
957 *
958 * This function must handle any surprises the peer may have for us, such as
959 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
960 * a surprise, but handled as if it were), or renegotiation requests.
961 * Also if record payloads contain fragments too small to process, we store
962 * them until there is enough for the respective protocol (the record protocol
963 * may use arbitrary fragmentation and even interleaving):
964 *     Change cipher spec protocol
965 *             just 1 byte needed, no need for keeping anything stored
966 *     Alert protocol
967 *             2 bytes needed (AlertLevel, AlertDescription)
968 *     Handshake protocol
969 *             4 bytes needed (HandshakeType, uint24 length) -- we just have
970 *             to detect unexpected Client Hello and Hello Request messages
971 *             here, anything else is handled by higher layers
972 *     Application data protocol
973 *             none of our business
974 */
975int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
976	{
977	int al,i,j,ret;
978	unsigned int n;
979	SSL3_RECORD *rr;
980	void (*cb)(const SSL *ssl,int type2,int val)=NULL;
981
982	if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
983		if (!ssl3_setup_read_buffer(s))
984			return(-1);
985
986	if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
987	    (peek && (type != SSL3_RT_APPLICATION_DATA)))
988		{
989		SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
990		return -1;
991		}
992
993	if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
994		/* (partially) satisfy request from storage */
995		{
996		unsigned char *src = s->s3->handshake_fragment;
997		unsigned char *dst = buf;
998		unsigned int k;
999
1000		/* peek == 0 */
1001		n = 0;
1002		while ((len > 0) && (s->s3->handshake_fragment_len > 0))
1003			{
1004			*dst++ = *src++;
1005			len--; s->s3->handshake_fragment_len--;
1006			n++;
1007			}
1008		/* move any remaining fragment bytes: */
1009		for (k = 0; k < s->s3->handshake_fragment_len; k++)
1010			s->s3->handshake_fragment[k] = *src++;
1011		return n;
1012	}
1013
1014	/* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
1015
1016	if (!s->in_handshake && SSL_in_init(s))
1017		{
1018		/* type == SSL3_RT_APPLICATION_DATA */
1019		i=s->handshake_func(s);
1020		if (i < 0) return(i);
1021		if (i == 0)
1022			{
1023			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1024			return(-1);
1025			}
1026		}
1027start:
1028	s->rwstate=SSL_NOTHING;
1029
1030	/* s->s3->rrec.type	    - is the type of record
1031	 * s->s3->rrec.data,    - data
1032	 * s->s3->rrec.off,     - offset into 'data' for next read
1033	 * s->s3->rrec.length,  - number of bytes. */
1034	rr = &(s->s3->rrec);
1035
1036	/* get new packet if necessary */
1037	if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1038		{
1039		ret=ssl3_get_record(s);
1040		if (ret <= 0) return(ret);
1041		}
1042
1043	/* we now have a packet which can be read and processed */
1044
1045	if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1046	                               * reset by ssl3_get_finished */
1047		&& (rr->type != SSL3_RT_HANDSHAKE))
1048		{
1049		al=SSL_AD_UNEXPECTED_MESSAGE;
1050		SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1051		goto f_err;
1052		}
1053
1054	/* If the other end has shut down, throw anything we read away
1055	 * (even in 'peek' mode) */
1056	if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1057		{
1058		rr->length=0;
1059		s->rwstate=SSL_NOTHING;
1060		return(0);
1061		}
1062
1063
1064	if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1065		{
1066		/* make sure that we are not getting application data when we
1067		 * are doing a handshake for the first time */
1068		if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1069			(s->enc_read_ctx == NULL))
1070			{
1071			al=SSL_AD_UNEXPECTED_MESSAGE;
1072			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1073			goto f_err;
1074			}
1075
1076		if (len <= 0) return(len);
1077
1078		if ((unsigned int)len > rr->length)
1079			n = rr->length;
1080		else
1081			n = (unsigned int)len;
1082
1083		memcpy(buf,&(rr->data[rr->off]),n);
1084		if (!peek)
1085			{
1086			rr->length-=n;
1087			rr->off+=n;
1088			if (rr->length == 0)
1089				{
1090				s->rstate=SSL_ST_READ_HEADER;
1091				rr->off=0;
1092				if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1093					ssl3_release_read_buffer(s);
1094				}
1095			}
1096		return(n);
1097		}
1098
1099
1100	/* If we get here, then type != rr->type; if we have a handshake
1101	 * message, then it was unexpected (Hello Request or Client Hello). */
1102
1103	/* In case of record types for which we have 'fragment' storage,
1104	 * fill that so that we can process the data at a fixed place.
1105	 */
1106		{
1107		unsigned int dest_maxlen = 0;
1108		unsigned char *dest = NULL;
1109		unsigned int *dest_len = NULL;
1110
1111		if (rr->type == SSL3_RT_HANDSHAKE)
1112			{
1113			dest_maxlen = sizeof s->s3->handshake_fragment;
1114			dest = s->s3->handshake_fragment;
1115			dest_len = &s->s3->handshake_fragment_len;
1116			}
1117		else if (rr->type == SSL3_RT_ALERT)
1118			{
1119			dest_maxlen = sizeof s->s3->alert_fragment;
1120			dest = s->s3->alert_fragment;
1121			dest_len = &s->s3->alert_fragment_len;
1122			}
1123#ifndef OPENSSL_NO_HEARTBEATS
1124		else if (rr->type == TLS1_RT_HEARTBEAT)
1125			{
1126			tls1_process_heartbeat(s);
1127
1128			/* Exit and notify application to read again */
1129			rr->length = 0;
1130			s->rwstate=SSL_READING;
1131			BIO_clear_retry_flags(SSL_get_rbio(s));
1132			BIO_set_retry_read(SSL_get_rbio(s));
1133			return(-1);
1134			}
1135#endif
1136
1137		if (dest_maxlen > 0)
1138			{
1139			n = dest_maxlen - *dest_len; /* available space in 'dest' */
1140			if (rr->length < n)
1141				n = rr->length; /* available bytes */
1142
1143			/* now move 'n' bytes: */
1144			while (n-- > 0)
1145				{
1146				dest[(*dest_len)++] = rr->data[rr->off++];
1147				rr->length--;
1148				}
1149
1150			if (*dest_len < dest_maxlen)
1151				goto start; /* fragment was too small */
1152			}
1153		}
1154
1155	/* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1156	 * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1157	 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1158
1159	/* If we are a client, check for an incoming 'Hello Request': */
1160	if ((!s->server) &&
1161		(s->s3->handshake_fragment_len >= 4) &&
1162		(s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1163		(s->session != NULL) && (s->session->cipher != NULL))
1164		{
1165		s->s3->handshake_fragment_len = 0;
1166
1167		if ((s->s3->handshake_fragment[1] != 0) ||
1168			(s->s3->handshake_fragment[2] != 0) ||
1169			(s->s3->handshake_fragment[3] != 0))
1170			{
1171			al=SSL_AD_DECODE_ERROR;
1172			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1173			goto f_err;
1174			}
1175
1176		if (s->msg_callback)
1177			s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1178
1179		if (SSL_is_init_finished(s) &&
1180			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1181			!s->s3->renegotiate)
1182			{
1183			ssl3_renegotiate(s);
1184			if (ssl3_renegotiate_check(s))
1185				{
1186				i=s->handshake_func(s);
1187				if (i < 0) return(i);
1188				if (i == 0)
1189					{
1190					SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1191					return(-1);
1192					}
1193
1194				if (!(s->mode & SSL_MODE_AUTO_RETRY))
1195					{
1196					if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1197						{
1198						BIO *bio;
1199						/* In the case where we try to read application data,
1200						 * but we trigger an SSL handshake, we return -1 with
1201						 * the retry option set.  Otherwise renegotiation may
1202						 * cause nasty problems in the blocking world */
1203						s->rwstate=SSL_READING;
1204						bio=SSL_get_rbio(s);
1205						BIO_clear_retry_flags(bio);
1206						BIO_set_retry_read(bio);
1207						return(-1);
1208						}
1209					}
1210				}
1211			}
1212		/* we either finished a handshake or ignored the request,
1213		 * now try again to obtain the (application) data we were asked for */
1214		goto start;
1215		}
1216	/* If we are a server and get a client hello when renegotiation isn't
1217	 * allowed send back a no renegotiation alert and carry on.
1218	 * WARNING: experimental code, needs reviewing (steve)
1219	 */
1220	if (s->server &&
1221		SSL_is_init_finished(s) &&
1222    		!s->s3->send_connection_binding &&
1223		(s->version > SSL3_VERSION) &&
1224		(s->s3->handshake_fragment_len >= 4) &&
1225		(s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1226		(s->session != NULL) && (s->session->cipher != NULL) &&
1227		!(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1228
1229		{
1230		/*s->s3->handshake_fragment_len = 0;*/
1231		rr->length = 0;
1232		ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1233		goto start;
1234		}
1235	if (s->s3->alert_fragment_len >= 2)
1236		{
1237		int alert_level = s->s3->alert_fragment[0];
1238		int alert_descr = s->s3->alert_fragment[1];
1239
1240		s->s3->alert_fragment_len = 0;
1241
1242		if (s->msg_callback)
1243			s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1244
1245		if (s->info_callback != NULL)
1246			cb=s->info_callback;
1247		else if (s->ctx->info_callback != NULL)
1248			cb=s->ctx->info_callback;
1249
1250		if (cb != NULL)
1251			{
1252			j = (alert_level << 8) | alert_descr;
1253			cb(s, SSL_CB_READ_ALERT, j);
1254			}
1255
1256		if (alert_level == 1) /* warning */
1257			{
1258			s->s3->warn_alert = alert_descr;
1259			if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1260				{
1261				s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1262				return(0);
1263				}
1264			/* This is a warning but we receive it if we requested
1265			 * renegotiation and the peer denied it. Terminate with
1266			 * a fatal alert because if application tried to
1267			 * renegotiatie it presumably had a good reason and
1268			 * expects it to succeed.
1269			 *
1270			 * In future we might have a renegotiation where we
1271			 * don't care if the peer refused it where we carry on.
1272			 */
1273			else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1274				{
1275				al = SSL_AD_HANDSHAKE_FAILURE;
1276				SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1277				goto f_err;
1278				}
1279#ifdef SSL_AD_MISSING_SRP_USERNAME
1280			if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1281				return(0);
1282#endif
1283			}
1284		else if (alert_level == 2) /* fatal */
1285			{
1286			char tmp[16];
1287
1288			s->rwstate=SSL_NOTHING;
1289			s->s3->fatal_alert = alert_descr;
1290			SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1291			BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1292			ERR_add_error_data(2,"SSL alert number ",tmp);
1293			s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1294			SSL_CTX_remove_session(s->ctx,s->session);
1295			return(0);
1296			}
1297		else
1298			{
1299			al=SSL_AD_ILLEGAL_PARAMETER;
1300			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1301			goto f_err;
1302			}
1303
1304		goto start;
1305		}
1306
1307	if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1308		{
1309		s->rwstate=SSL_NOTHING;
1310		rr->length=0;
1311		return(0);
1312		}
1313
1314	if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1315		{
1316		/* 'Change Cipher Spec' is just a single byte, so we know
1317		 * exactly what the record payload has to look like */
1318		if (	(rr->length != 1) || (rr->off != 0) ||
1319			(rr->data[0] != SSL3_MT_CCS))
1320			{
1321			al=SSL_AD_ILLEGAL_PARAMETER;
1322			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1323			goto f_err;
1324			}
1325
1326		/* Check we have a cipher to change to */
1327		if (s->s3->tmp.new_cipher == NULL)
1328			{
1329			al=SSL_AD_UNEXPECTED_MESSAGE;
1330			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1331			goto f_err;
1332			}
1333
1334		rr->length=0;
1335
1336		if (s->msg_callback)
1337			s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1338
1339		s->s3->change_cipher_spec=1;
1340		if (!ssl3_do_change_cipher_spec(s))
1341			goto err;
1342		else
1343			goto start;
1344		}
1345
1346	/* Unexpected handshake message (Client Hello, or protocol violation) */
1347	if ((s->s3->handshake_fragment_len >= 4) &&	!s->in_handshake)
1348		{
1349		if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1350			!(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1351			{
1352#if 0 /* worked only because C operator preferences are not as expected (and
1353       * because this is not really needed for clients except for detecting
1354       * protocol violations): */
1355			s->state=SSL_ST_BEFORE|(s->server)
1356				?SSL_ST_ACCEPT
1357				:SSL_ST_CONNECT;
1358#else
1359			s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1360#endif
1361			s->renegotiate=1;
1362			s->new_session=1;
1363			}
1364		i=s->handshake_func(s);
1365		if (i < 0) return(i);
1366		if (i == 0)
1367			{
1368			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1369			return(-1);
1370			}
1371
1372		if (!(s->mode & SSL_MODE_AUTO_RETRY))
1373			{
1374			if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1375				{
1376				BIO *bio;
1377				/* In the case where we try to read application data,
1378				 * but we trigger an SSL handshake, we return -1 with
1379				 * the retry option set.  Otherwise renegotiation may
1380				 * cause nasty problems in the blocking world */
1381				s->rwstate=SSL_READING;
1382				bio=SSL_get_rbio(s);
1383				BIO_clear_retry_flags(bio);
1384				BIO_set_retry_read(bio);
1385				return(-1);
1386				}
1387			}
1388		goto start;
1389		}
1390
1391	switch (rr->type)
1392		{
1393	default:
1394#ifndef OPENSSL_NO_TLS
1395		/* TLS up to v1.1 just ignores unknown message types:
1396		 * TLS v1.2 give an unexpected message alert.
1397		 */
1398		if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1399			{
1400			rr->length = 0;
1401			goto start;
1402			}
1403#endif
1404		al=SSL_AD_UNEXPECTED_MESSAGE;
1405		SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1406		goto f_err;
1407	case SSL3_RT_CHANGE_CIPHER_SPEC:
1408	case SSL3_RT_ALERT:
1409	case SSL3_RT_HANDSHAKE:
1410		/* we already handled all of these, with the possible exception
1411		 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1412		 * should not happen when type != rr->type */
1413		al=SSL_AD_UNEXPECTED_MESSAGE;
1414		SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1415		goto f_err;
1416	case SSL3_RT_APPLICATION_DATA:
1417		/* At this point, we were expecting handshake data,
1418		 * but have application data.  If the library was
1419		 * running inside ssl3_read() (i.e. in_read_app_data
1420		 * is set) and it makes sense to read application data
1421		 * at this point (session renegotiation not yet started),
1422		 * we will indulge it.
1423		 */
1424		if (s->s3->in_read_app_data &&
1425			(s->s3->total_renegotiations != 0) &&
1426			((
1427				(s->state & SSL_ST_CONNECT) &&
1428				(s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1429				(s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1430				) || (
1431					(s->state & SSL_ST_ACCEPT) &&
1432					(s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1433					(s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1434					)
1435				))
1436			{
1437			s->s3->in_read_app_data=2;
1438			return(-1);
1439			}
1440		else
1441			{
1442			al=SSL_AD_UNEXPECTED_MESSAGE;
1443			SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1444			goto f_err;
1445			}
1446		}
1447	/* not reached */
1448
1449f_err:
1450	ssl3_send_alert(s,SSL3_AL_FATAL,al);
1451err:
1452	return(-1);
1453	}
1454
1455int ssl3_do_change_cipher_spec(SSL *s)
1456	{
1457	int i;
1458	const char *sender;
1459	int slen;
1460
1461	if (s->state & SSL_ST_ACCEPT)
1462		i=SSL3_CHANGE_CIPHER_SERVER_READ;
1463	else
1464		i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1465
1466	if (s->s3->tmp.key_block == NULL)
1467		{
1468		if (s->session == NULL)
1469			{
1470			/* might happen if dtls1_read_bytes() calls this */
1471			SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1472			return (0);
1473			}
1474
1475		s->session->cipher=s->s3->tmp.new_cipher;
1476		if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1477		}
1478
1479	if (!s->method->ssl3_enc->change_cipher_state(s,i))
1480		return(0);
1481
1482	/* we have to record the message digest at
1483	 * this point so we can get it before we read
1484	 * the finished message */
1485	if (s->state & SSL_ST_CONNECT)
1486		{
1487		sender=s->method->ssl3_enc->server_finished_label;
1488		slen=s->method->ssl3_enc->server_finished_label_len;
1489		}
1490	else
1491		{
1492		sender=s->method->ssl3_enc->client_finished_label;
1493		slen=s->method->ssl3_enc->client_finished_label_len;
1494		}
1495
1496	s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1497		sender,slen,s->s3->tmp.peer_finish_md);
1498
1499	return(1);
1500	}
1501
1502int ssl3_send_alert(SSL *s, int level, int desc)
1503	{
1504	/* Map tls/ssl alert value to correct one */
1505	desc=s->method->ssl3_enc->alert_value(desc);
1506	if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1507		desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1508	if (desc < 0) return -1;
1509	/* If a fatal one, remove from cache */
1510	if ((level == 2) && (s->session != NULL))
1511		SSL_CTX_remove_session(s->ctx,s->session);
1512
1513	s->s3->alert_dispatch=1;
1514	s->s3->send_alert[0]=level;
1515	s->s3->send_alert[1]=desc;
1516	if (s->s3->wbuf.left == 0) /* data still being written out? */
1517		return s->method->ssl_dispatch_alert(s);
1518	/* else data is still being written out, we will get written
1519	 * some time in the future */
1520	return -1;
1521	}
1522
1523int ssl3_dispatch_alert(SSL *s)
1524	{
1525	int i,j;
1526	void (*cb)(const SSL *ssl,int type,int val)=NULL;
1527
1528	s->s3->alert_dispatch=0;
1529	i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1530	if (i <= 0)
1531		{
1532		s->s3->alert_dispatch=1;
1533		}
1534	else
1535		{
1536		/* Alert sent to BIO.  If it is important, flush it now.
1537		 * If the message does not get sent due to non-blocking IO,
1538		 * we will not worry too much. */
1539		if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1540			(void)BIO_flush(s->wbio);
1541
1542		if (s->msg_callback)
1543			s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1544
1545		if (s->info_callback != NULL)
1546			cb=s->info_callback;
1547		else if (s->ctx->info_callback != NULL)
1548			cb=s->ctx->info_callback;
1549
1550		if (cb != NULL)
1551			{
1552			j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1553			cb(s,SSL_CB_WRITE_ALERT,j);
1554			}
1555		}
1556	return(i);
1557	}
1558