3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
6 /* ====================================================================
7 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * openssl-core@openssl.org.
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
35 * 6. Redistributions of any form whatsoever must retain the following
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60 * All rights reserved.
62 * This package is an SSL implementation written
63 * by Eric Young (eay@cryptsoft.com).
64 * The implementation was written so as to conform with Netscapes SSL.
66 * This library is free for commercial and non-commercial use as long as
67 * the following conditions are aheared to. The following conditions
68 * apply to all code found in this distribution, be it the RC4, RSA,
69 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
70 * included with this distribution is covered by the same copyright terms
71 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
73 * Copyright remains Eric Young's, and as such any Copyright notices in
74 * the code are not to be removed.
75 * If this package is used in a product, Eric Young should be given attribution
76 * as the author of the parts of the library used.
77 * This can be in the form of a textual message at program startup or
78 * in documentation (online or textual) provided with the package.
80 * Redistribution and use in source and binary forms, with or without
81 * modification, are permitted provided that the following conditions
83 * 1. Redistributions of source code must retain the copyright
84 * notice, this list of conditions and the following disclaimer.
85 * 2. Redistributions in binary form must reproduce the above copyright
86 * notice, this list of conditions and the following disclaimer in the
87 * documentation and/or other materials provided with the distribution.
88 * 3. All advertising materials mentioning features or use of this software
89 * must display the following acknowledgement:
90 * "This product includes cryptographic software written by
91 * Eric Young (eay@cryptsoft.com)"
92 * The word 'cryptographic' can be left out if the rouines from the library
93 * being used are not cryptographic related :-).
94 * 4. If you include any Windows specific code (or a derivative thereof) from
95 * the apps directory (application code) you must include an acknowledgement:
96 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
98 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
110 * The licence and distribution terms for any publically available version or
111 * derivative of this code cannot be changed. i.e. this code cannot simply be
112 * copied and put under another distribution licence
113 * [including the GNU Public Licence.]
119 #include "ssl_locl.h"
120 #include <openssl/buffer.h>
121 #include <openssl/rand.h>
122 #include <openssl/objects.h>
123 #include <openssl/evp.h>
124 #include <openssl/x509.h>
127 /* XDTLS: figure out the right values */
128 static unsigned int g_probable_mtu
[] = {1500 - 28, 512 - 28, 256 - 28};
130 static unsigned int dtls1_min_mtu(void);
131 static unsigned int dtls1_guess_mtu(unsigned int curr_mtu
);
132 static void dtls1_fix_message_header(SSL
*s
, unsigned long frag_off
,
133 unsigned long frag_len
);
134 static unsigned char *dtls1_write_message_header(SSL
*s
,
136 static void dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
137 unsigned long len
, unsigned short seq_num
, unsigned long frag_off
,
138 unsigned long frag_len
);
139 static int dtls1_retransmit_buffered_messages(SSL
*s
);
140 static long dtls1_get_message_fragment(SSL
*s
, int st1
, int stn
,
142 static void dtls1_process_handshake_fragment(SSL
*s
, int frag_len
);
145 dtls1_hm_fragment_new(unsigned long frag_len
)
147 hm_fragment
*frag
= NULL
;
148 unsigned char *buf
= NULL
;
150 frag
= (hm_fragment
*)OPENSSL_malloc(sizeof(hm_fragment
));
154 buf
= (unsigned char *)OPENSSL_malloc(frag_len
155 + DTLS1_HM_HEADER_LENGTH
);
162 frag
->fragment
= buf
;
168 dtls1_hm_fragment_free(hm_fragment
*frag
)
170 OPENSSL_free(frag
->fragment
);
174 /* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */
175 int dtls1_do_write(SSL
*s
, int type
)
179 unsigned int len
, frag_off
;
181 /* AHA! Figure out the MTU, and stick to the right size */
182 if ( ! (SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
))
185 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_QUERY_MTU
, 0, NULL
);
187 /* I've seen the kernel return bogus numbers when it doesn't know
188 * (initial write), so just make sure we have a reasonable number */
189 if ( s
->d1
->mtu
< dtls1_min_mtu())
192 s
->d1
->mtu
= dtls1_guess_mtu(s
->d1
->mtu
);
193 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SET_MTU
,
200 fprintf(stderr
, "using MTU = %d\n", mtu
);
202 mtu
-= (DTLS1_HM_HEADER_LENGTH
+ DTLS1_RT_HEADER_LENGTH
);
204 curr_mtu
= mtu
- BIO_wpending(SSL_get_wbio(s
));
208 else if ( ( ret
= BIO_flush(SSL_get_wbio(s
))) <= 0)
211 if ( BIO_wpending(SSL_get_wbio(s
)) + s
->init_num
>= mtu
)
213 ret
= BIO_flush(SSL_get_wbio(s
));
216 mtu
= s
->d1
->mtu
- (DTLS1_HM_HEADER_LENGTH
+ DTLS1_RT_HEADER_LENGTH
);
219 OPENSSL_assert(mtu
> 0); /* should have something reasonable now */
223 if ( s
->init_off
== 0 && type
== SSL3_RT_HANDSHAKE
)
224 OPENSSL_assert(s
->init_num
==
225 s
->d1
->w_msg_hdr
.msg_len
+ DTLS1_HM_HEADER_LENGTH
);
230 curr_mtu
= s
->d1
->mtu
- BIO_wpending(SSL_get_wbio(s
)) -
231 DTLS1_RT_HEADER_LENGTH
;
233 if ( curr_mtu
<= DTLS1_HM_HEADER_LENGTH
)
235 /* grr.. we could get an error if MTU picked was wrong */
236 ret
= BIO_flush(SSL_get_wbio(s
));
239 curr_mtu
= s
->d1
->mtu
- DTLS1_RT_HEADER_LENGTH
;
242 if ( s
->init_num
> curr_mtu
)
248 /* XDTLS: this function is too long. split out the CCS part */
249 if ( type
== SSL3_RT_HANDSHAKE
)
251 if ( s
->init_off
!= 0)
253 OPENSSL_assert(s
->init_off
> DTLS1_HM_HEADER_LENGTH
);
254 s
->init_off
-= DTLS1_HM_HEADER_LENGTH
;
255 s
->init_num
+= DTLS1_HM_HEADER_LENGTH
;
257 /* write atleast DTLS1_HM_HEADER_LENGTH bytes */
258 if ( len
<= DTLS1_HM_HEADER_LENGTH
)
259 len
+= DTLS1_HM_HEADER_LENGTH
;
262 dtls1_fix_message_header(s
, frag_off
,
263 len
- DTLS1_HM_HEADER_LENGTH
);
265 dtls1_write_message_header(s
, (unsigned char *)&s
->init_buf
->data
[s
->init_off
]);
267 OPENSSL_assert(len
>= DTLS1_HM_HEADER_LENGTH
);
270 ret
=dtls1_write_bytes(s
,type
,&s
->init_buf
->data
[s
->init_off
],
274 /* might need to update MTU here, but we don't know
275 * which previous packet caused the failure -- so can't
276 * really retransmit anything. continue as if everything
277 * is fine and wait for an alert to handle the
280 if ( BIO_ctrl(SSL_get_wbio(s
),
281 BIO_CTRL_DGRAM_MTU_EXCEEDED
, 0, NULL
))
282 s
->d1
->mtu
= BIO_ctrl(SSL_get_wbio(s
),
283 BIO_CTRL_DGRAM_QUERY_MTU
, 0, NULL
);
290 /* bad if this assert fails, only part of the handshake
291 * message got sent. but why would this happen? */
292 OPENSSL_assert(len
== ret
);
294 if (type
== SSL3_RT_HANDSHAKE
&& ! s
->d1
->retransmitting
)
295 /* should not be done for 'Hello Request's, but in that case
296 * we'll ignore the result anyway */
298 (unsigned char *)&s
->init_buf
->data
[s
->init_off
+
299 DTLS1_HM_HEADER_LENGTH
], ret
- DTLS1_HM_HEADER_LENGTH
);
301 if (ret
== s
->init_num
)
304 s
->msg_callback(1, s
->version
, type
, s
->init_buf
->data
,
305 (size_t)(s
->init_off
+ s
->init_num
), s
,
306 s
->msg_callback_arg
);
308 s
->init_off
= 0; /* done writing this message */
315 frag_off
+= (ret
-= DTLS1_HM_HEADER_LENGTH
);
322 /* Obtain handshake message of message type 'mt' (any if mt == -1),
323 * maximum acceptable body length 'max'.
324 * Read an entire handshake message. Handshake messages arrive in
327 long dtls1_get_message(SSL
*s
, int st1
, int stn
, int mt
, long max
,
332 /* s3->tmp is used to store messages that are unexpected, caused
333 * by the absence of an optional handshake message */
334 if (s
->s3
->tmp
.reuse_message
)
336 s
->s3
->tmp
.reuse_message
=0;
337 if ((mt
>= 0) && (s
->s3
->tmp
.message_type
!= mt
))
339 al
=SSL_AD_UNEXPECTED_MESSAGE
;
340 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_UNEXPECTED_MESSAGE
);
344 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
345 s
->init_num
= (int)s
->s3
->tmp
.message_size
;
351 if ( s
->d1
->r_msg_hdr
.frag_off
== 0)
353 /* s->d1->r_message_header.msg_len = 0; */
354 memset(&(s
->d1
->r_msg_hdr
), 0x00, sizeof(struct hm_header_st
));
357 i
= dtls1_get_message_fragment(s
, st1
, stn
, max
, ok
);
358 if ( i
== DTLS1_HM_BAD_FRAGMENT
||
359 i
== DTLS1_HM_FRAGMENT_RETRY
) /* bad fragment received */
361 else if ( i
<= 0 && !*ok
)
364 if (s
->d1
->r_msg_hdr
.msg_len
== s
->init_num
- DTLS1_HM_HEADER_LENGTH
)
366 memset(&(s
->d1
->r_msg_hdr
), 0x00, sizeof(struct hm_header_st
));
368 s
->d1
->handshake_read_seq
++;
369 /* we just read a handshake message from the other side:
370 * this means that we don't need to retransmit of the
372 * XDTLS: may be able clear out this
373 * buffer a little sooner (i.e if an out-of-order
374 * handshake message/record is received at the record
376 * XDTLS: exception is that the server needs to
377 * know that change cipher spec and finished messages
378 * have been received by the client before clearing this
379 * buffer. this can simply be done by waiting for the
380 * first data segment, but is there a better way? */
381 dtls1_clear_record_buffer(s
);
383 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
384 return s
->init_num
- DTLS1_HM_HEADER_LENGTH
;
387 s
->d1
->r_msg_hdr
.frag_off
= i
;
391 ssl3_send_alert(s
,SSL3_AL_FATAL
,al
);
398 dtls1_retrieve_buffered_fragment(SSL
*s
, unsigned long *copied
)
400 /* (0) check whether the desired fragment is available
402 * (1) copy over the fragment to s->init_buf->data[]
403 * (2) update s->init_num
407 unsigned long overlap
;
410 item
= pqueue_peek(s
->d1
->buffered_messages
);
414 frag
= (hm_fragment
*)item
->data
;
416 if ( s
->d1
->handshake_read_seq
== frag
->msg_header
.seq
&&
417 frag
->msg_header
.frag_off
<= s
->init_num
- DTLS1_HM_HEADER_LENGTH
)
419 pqueue_pop(s
->d1
->buffered_messages
);
420 overlap
= s
->init_num
- DTLS1_HM_HEADER_LENGTH
421 - frag
->msg_header
.frag_off
;
425 memcpy(&s
->init_buf
->data
[s
->init_num
],
426 p
+ DTLS1_HM_HEADER_LENGTH
+ overlap
,
427 frag
->msg_header
.frag_len
- overlap
);
429 OPENSSL_free(frag
->fragment
);
433 *copied
= frag
->msg_header
.frag_len
- overlap
;
442 dtls1_buffer_handshake_fragment(SSL
*s
, struct hm_header_st
* msg_hdr
)
444 hm_fragment
*frag
= NULL
;
447 frag
= dtls1_hm_fragment_new(msg_hdr
->frag_len
);
451 memcpy(frag
->fragment
, &(s
->init_buf
->data
[s
->init_num
]),
452 msg_hdr
->frag_len
+ DTLS1_HM_HEADER_LENGTH
);
454 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
456 item
= pitem_new(msg_hdr
->seq
, frag
);
460 pqueue_insert(s
->d1
->buffered_messages
, item
);
464 if ( frag
!= NULL
) dtls1_hm_fragment_free(frag
);
465 if ( item
!= NULL
) OPENSSL_free(item
);
471 dtls1_process_handshake_fragment(SSL
*s
, int frag_len
)
475 p
= (unsigned char *)s
->init_buf
->data
;
477 ssl3_finish_mac(s
, &p
[s
->init_num
- frag_len
], frag_len
);
482 dtls1_process_out_of_seq_message(SSL
*s
, struct hm_header_st
*msg_hdr
, int *ok
)
487 /* make sure there's enough room to read this fragment */
488 if ( (int)msg_hdr
->frag_len
&& !BUF_MEM_grow_clean(s
->init_buf
,
489 (int)msg_hdr
->frag_len
+ DTLS1_HM_HEADER_LENGTH
+ s
->init_num
))
491 SSLerr(SSL_F_SSL3_GET_MESSAGE
,ERR_R_BUF_LIB
);
495 p
= (unsigned char *)s
->init_buf
->data
;
497 /* read the body of the fragment (header has already been read */
498 if ( msg_hdr
->frag_len
> 0)
500 i
=s
->method
->ssl_read_bytes(s
,SSL3_RT_HANDSHAKE
,
502 msg_hdr
->frag_len
,0);
510 if ( msg_hdr
->seq
> s
->d1
->handshake_read_seq
)
511 dtls1_buffer_handshake_fragment(s
, msg_hdr
);
513 OPENSSL_assert(msg_hdr
->seq
< s
->d1
->handshake_read_seq
);
515 return DTLS1_HM_FRAGMENT_RETRY
;
523 dtls1_get_message_fragment(SSL
*s
, int st1
, int stn
, long max
, int *ok
)
526 unsigned long l
, frag_off
, frag_len
;
528 struct hm_header_st msg_hdr
;
529 unsigned long overlap
;
531 /* see if we have the required fragment already */
532 if (dtls1_retrieve_buffered_fragment(s
, &l
))
534 /* compute MAC, remove fragment headers */
535 dtls1_process_handshake_fragment(s
, l
);
536 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
541 /* get a handshake fragment from the record layer */
542 p
= (unsigned char *)s
->init_buf
->data
;
544 /* read handshake message header */
545 i
=s
->method
->ssl_read_bytes(s
,SSL3_RT_HANDSHAKE
,&p
[s
->init_num
],
546 DTLS1_HM_HEADER_LENGTH
, 0);
547 if (i
<= 0) /* nbio, or an error */
549 s
->rwstate
=SSL_READING
;
554 OPENSSL_assert(i
== DTLS1_HM_HEADER_LENGTH
);
557 /* parse the message fragment header */
559 dtls1_get_message_header(p
, &msg_hdr
);
562 * if this is a future (or stale) message it gets buffered
563 * (or dropped)--no further processing at this time
565 if ( msg_hdr
.seq
!= s
->d1
->handshake_read_seq
)
566 return dtls1_process_out_of_seq_message(s
, &msg_hdr
, ok
);
569 frag_off
= msg_hdr
.frag_off
;
570 frag_len
= msg_hdr
.frag_len
;
572 /* sanity checking */
573 if ( frag_off
+ frag_len
> l
)
575 al
=SSL_AD_ILLEGAL_PARAMETER
;
576 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_EXCESSIVE_MESSAGE_SIZE
);
580 if (!s
->server
&& s
->d1
->r_msg_hdr
.frag_off
== 0 &&
581 p
[0] == SSL3_MT_HELLO_REQUEST
)
583 /* The server may always send 'Hello Request' messages --
584 * we are doing a handshake anyway now, so ignore them
585 * if their format is correct. Does not count for
587 if (p
[1] == 0 && p
[2] == 0 &&p
[3] == 0)
590 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
591 p
, DTLS1_HM_HEADER_LENGTH
, s
,
592 s
->msg_callback_arg
);
595 return dtls1_get_message_fragment(s
, st1
, stn
,
598 else /* Incorrectly formated Hello request */
600 al
=SSL_AD_UNEXPECTED_MESSAGE
;
601 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_UNEXPECTED_MESSAGE
);
606 /* XDTLS: do a sanity check on the fragment */
610 if ( s
->d1
->r_msg_hdr
.frag_off
== 0) /* first fragment */
612 /* BUF_MEM_grow takes an 'int' parameter */
613 if (l
> (INT_MAX
-DTLS1_HM_HEADER_LENGTH
))
615 al
=SSL_AD_ILLEGAL_PARAMETER
;
616 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_EXCESSIVE_MESSAGE_SIZE
);
619 if (l
&& !BUF_MEM_grow_clean(s
->init_buf
,(int)l
620 + DTLS1_HM_HEADER_LENGTH
))
622 SSLerr(SSL_F_SSL3_GET_MESSAGE
,ERR_R_BUF_LIB
);
625 /* Only do this test when we're reading the expected message.
626 * Stale messages will be dropped and future messages will be buffered */
627 if ( l
> (unsigned long)max
)
629 al
=SSL_AD_ILLEGAL_PARAMETER
;
630 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_EXCESSIVE_MESSAGE_SIZE
);
634 s
->s3
->tmp
.message_size
=l
;
637 if ( frag_len
> (unsigned long)max
)
639 al
=SSL_AD_ILLEGAL_PARAMETER
;
640 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_EXCESSIVE_MESSAGE_SIZE
);
643 if ( frag_len
+ s
->init_num
> (INT_MAX
- DTLS1_HM_HEADER_LENGTH
))
645 al
=SSL_AD_ILLEGAL_PARAMETER
;
646 SSLerr(SSL_F_SSL3_GET_MESSAGE
,SSL_R_EXCESSIVE_MESSAGE_SIZE
);
650 if ( frag_len
& !BUF_MEM_grow_clean(s
->init_buf
, (int)frag_len
651 + DTLS1_HM_HEADER_LENGTH
+ s
->init_num
))
653 SSLerr(SSL_F_SSL3_GET_MESSAGE
,ERR_R_BUF_LIB
);
657 if ( s
->d1
->r_msg_hdr
.frag_off
== 0)
659 s
->s3
->tmp
.message_type
= msg_hdr
.type
;
660 s
->d1
->r_msg_hdr
.type
= msg_hdr
.type
;
661 s
->d1
->r_msg_hdr
.msg_len
= l
;
662 /* s->d1->r_msg_hdr.seq = seq_num; */
665 /* XDTLS: ressurect this when restart is in place */
668 /* next state (stn) */
669 p
= (unsigned char *)s
->init_buf
->data
;
673 i
=s
->method
->ssl_read_bytes(s
,SSL3_RT_HANDSHAKE
,
676 /* XDTLS: fix this--message fragments cannot span multiple packets */
679 s
->rwstate
=SSL_READING
;
687 /* XDTLS: an incorrectly formatted fragment should cause the
688 * handshake to fail */
689 OPENSSL_assert(i
== frag_len
);
692 /* Successfully read a fragment.
693 * It may be (1) out of order, or
694 * (2) it's a repeat, in which case we dump it
695 * (3) the one we are expecting next (maybe with overlap)
696 * If it is next one, it may overlap with previously read bytes
699 /* case (1): buffer the future fragment
700 * (we can treat fragments from a future message the same
701 * as future fragments from the message being currently read, since
702 * they are sematically simply out of order.
704 if ( msg_hdr
.seq
> s
->d1
->handshake_read_seq
||
705 frag_off
> s
->init_num
- DTLS1_HM_HEADER_LENGTH
)
707 dtls1_buffer_handshake_fragment(s
, &msg_hdr
);
708 return DTLS1_HM_FRAGMENT_RETRY
;
711 /* case (2): drop the entire fragment, and try again */
712 if ( msg_hdr
.seq
< s
->d1
->handshake_read_seq
||
713 frag_off
+ frag_len
< s
->init_num
- DTLS1_HM_HEADER_LENGTH
)
715 s
->init_num
-= DTLS1_HM_HEADER_LENGTH
;
716 return DTLS1_HM_FRAGMENT_RETRY
;
720 /* case (3): received a immediately useful fragment. Determine the
721 * possible overlap and copy the fragment.
723 overlap
= (s
->init_num
- DTLS1_HM_HEADER_LENGTH
) - frag_off
;
725 /* retain the header for the first fragment */
726 if ( s
->init_num
> DTLS1_HM_HEADER_LENGTH
)
728 memmove(&(s
->init_buf
->data
[s
->init_num
]),
729 &(s
->init_buf
->data
[s
->init_num
+ DTLS1_HM_HEADER_LENGTH
+ overlap
]),
732 s
->init_num
+= frag_len
- overlap
;
735 s
->init_num
+= frag_len
;
737 dtls1_process_handshake_fragment(s
, frag_len
- overlap
);
740 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
, s
->init_buf
->data
,
741 (size_t)s
->init_num
, s
,
742 s
->msg_callback_arg
);
748 ssl3_send_alert(s
,SSL3_AL_FATAL
,al
);
755 int dtls1_send_finished(SSL
*s
, int a
, int b
, const char *sender
, int slen
)
763 d
=(unsigned char *)s
->init_buf
->data
;
764 p
= &(d
[DTLS1_HM_HEADER_LENGTH
]);
766 i
=s
->method
->ssl3_enc
->final_finish_mac(s
,
767 &(s
->s3
->finish_dgst1
),
768 &(s
->s3
->finish_dgst2
),
769 sender
,slen
,s
->s3
->tmp
.finish_md
);
770 s
->s3
->tmp
.finish_md_len
= i
;
771 memcpy(p
, s
->s3
->tmp
.finish_md
, i
);
775 #ifdef OPENSSL_SYS_WIN16
776 /* MSVC 1.5 does not clear the top bytes of the word unless
782 d
= dtls1_set_message_header(s
, d
, SSL3_MT_FINISHED
, l
, 0, l
);
783 s
->init_num
=(int)l
+DTLS1_HM_HEADER_LENGTH
;
786 /* buffer the message to handle re-xmits */
787 dtls1_buffer_message(s
, 0);
792 /* SSL3_ST_SEND_xxxxxx_HELLO_B */
793 return(dtls1_do_write(s
,SSL3_RT_HANDSHAKE
));
796 /* for these 2 messages, we need to
797 * ssl->enc_read_ctx re-init
798 * ssl->s3->read_sequence zero
799 * ssl->s3->read_mac_secret re-init
800 * ssl->session->read_sym_enc assign
801 * ssl->session->read_compression assign
802 * ssl->session->read_hash assign
804 int dtls1_send_change_cipher_spec(SSL
*s
, int a
, int b
)
810 p
=(unsigned char *)s
->init_buf
->data
;
812 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
813 s
->d1
->next_handshake_write_seq
++;
814 s2n(s
->d1
->handshake_write_seq
,p
);
816 s
->init_num
=DTLS1_CCS_HEADER_LENGTH
;
819 dtls1_set_message_header_int(s
, SSL3_MT_CCS
, 0,
820 s
->d1
->handshake_write_seq
, 0, 0);
822 /* buffer the message to handle re-xmits */
823 dtls1_buffer_message(s
, 1);
828 /* SSL3_ST_CW_CHANGE_B */
829 return(dtls1_do_write(s
,SSL3_RT_CHANGE_CIPHER_SPEC
));
832 unsigned long dtls1_output_cert_chain(SSL
*s
, X509
*x
)
836 unsigned long l
= 3 + DTLS1_HM_HEADER_LENGTH
;
838 X509_STORE_CTX xs_ctx
;
841 /* TLSv1 sends a chain with nothing in it, instead of an alert */
843 if (!BUF_MEM_grow_clean(buf
,10))
845 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN
,ERR_R_BUF_LIB
);
850 if(!X509_STORE_CTX_init(&xs_ctx
,s
->ctx
->cert_store
,NULL
,NULL
))
852 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN
,ERR_R_X509_LIB
);
859 if (!BUF_MEM_grow_clean(buf
,(int)(n
+l
+3)))
861 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN
,ERR_R_BUF_LIB
);
864 p
=(unsigned char *)&(buf
->data
[l
]);
868 if (X509_NAME_cmp(X509_get_subject_name(x
),
869 X509_get_issuer_name(x
)) == 0) break;
871 i
=X509_STORE_get_by_subject(&xs_ctx
,X509_LU_X509
,
872 X509_get_issuer_name(x
),&obj
);
875 /* Count is one too high since the X509_STORE_get uped the
880 X509_STORE_CTX_cleanup(&xs_ctx
);
883 /* Thawte special :-) */
884 if (s
->ctx
->extra_certs
!= NULL
)
885 for (i
=0; i
<sk_X509_num(s
->ctx
->extra_certs
); i
++)
887 x
=sk_X509_value(s
->ctx
->extra_certs
,i
);
889 if (!BUF_MEM_grow_clean(buf
,(int)(n
+l
+3)))
891 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN
,ERR_R_BUF_LIB
);
894 p
=(unsigned char *)&(buf
->data
[l
]);
900 l
-= (3 + DTLS1_HM_HEADER_LENGTH
);
902 p
=(unsigned char *)&(buf
->data
[DTLS1_HM_HEADER_LENGTH
]);
905 p
=(unsigned char *)&(buf
->data
[0]);
906 p
= dtls1_set_message_header(s
, p
, SSL3_MT_CERTIFICATE
, l
, 0, l
);
908 l
+=DTLS1_HM_HEADER_LENGTH
;
912 int dtls1_read_failed(SSL
*s
, int code
)
920 fprintf( stderr
, "invalid state reached %s:%d", __FILE__
, __LINE__
);
924 bio
= SSL_get_rbio(s
);
925 if ( ! BIO_dgram_recv_timedout(bio
))
927 /* not a timeout, none of our business,
928 let higher layers handle this. in fact it's probably an error */
932 if ( ! SSL_in_init(s
)) /* done, no need to send a retransmit */
934 BIO_set_flags(SSL_get_rbio(s
), BIO_FLAGS_READ
);
939 state
->timeout
.num_alerts
++;
940 if ( state
->timeout
.num_alerts
> DTLS1_TMO_ALERT_COUNT
)
942 /* fail the connection, enough alerts have been sent */
943 SSLerr(SSL_F_DTLS1_READ_FAILED
,SSL_R_READ_TIMEOUT_EXPIRED
);
947 state
->timeout
.read_timeouts
++;
948 if ( state
->timeout
.read_timeouts
> DTLS1_TMO_READ_COUNT
)
951 state
->timeout
.read_timeouts
= 1;
955 #if 0 /* for now, each alert contains only one record number */
956 item
= pqueue_peek(state
->rcvd_records
);
959 /* send an alert immediately for all the missing records */
964 #if 0 /* no more alert sending, just retransmit the last set of messages */
966 ssl3_send_alert(s
,SSL3_AL_WARNING
,
967 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
);
970 return dtls1_retransmit_buffered_messages(s
) ;
975 dtls1_retransmit_buffered_messages(SSL
*s
)
977 pqueue sent
= s
->d1
->sent_messages
;
983 iter
= pqueue_iterator(sent
);
985 for ( item
= pqueue_next(&iter
); item
!= NULL
; item
= pqueue_next(&iter
))
987 frag
= (hm_fragment
*)item
->data
;
988 if ( dtls1_retransmit_message(s
, frag
->msg_header
.seq
, 0, &found
) <= 0 &&
991 fprintf(stderr
, "dtls1_retransmit_message() failed\n");
1000 static dtls1_message_buffer
*
1001 dtls1_message_buffer_new(unsigned int len
)
1003 dtls1_message_buffer
*msg_buf
;
1005 msg_buf
= (dtls1_message_buffer
*)
1006 OPENSSL_malloc(sizeof(dtls1_message_buffer
));
1007 if ( msg_buf
== NULL
)
1010 memset(msg_buf
, 0x00, sizeof(dtls1_message_buffer
));
1012 msg_buf
->data
= (unsigned char *) OPENSSL_malloc(len
);
1013 if ( msg_buf
->data
== NULL
)
1015 OPENSSL_free(msg_buf
);
1019 memset(msg_buf
->data
, 0x00, len
);
1026 dtls1_message_buffer_free(dtls1_message_buffer
*msg_buf
)
1028 if (msg_buf
!= NULL
)
1030 OPENSSL_free(msg_buf
->data
);
1031 OPENSSL_free(msg_buf
);
1037 dtls1_buffer_message(SSL
*s
, int is_ccs
)
1042 /* this function is called immediately after a message has
1043 * been serialized */
1044 OPENSSL_assert(s
->init_off
== 0);
1046 frag
= dtls1_hm_fragment_new(s
->init_num
);
1048 memcpy(frag
->fragment
, s
->init_buf
->data
, s
->init_num
);
1052 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
1053 DTLS1_CCS_HEADER_LENGTH
== s
->init_num
);
1057 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
1058 DTLS1_HM_HEADER_LENGTH
== s
->init_num
);
1061 frag
->msg_header
.msg_len
= s
->d1
->w_msg_hdr
.msg_len
;
1062 frag
->msg_header
.seq
= s
->d1
->w_msg_hdr
.seq
;
1063 frag
->msg_header
.type
= s
->d1
->w_msg_hdr
.type
;
1064 frag
->msg_header
.frag_off
= 0;
1065 frag
->msg_header
.frag_len
= s
->d1
->w_msg_hdr
.msg_len
;
1066 frag
->msg_header
.is_ccs
= is_ccs
;
1068 item
= pitem_new(frag
->msg_header
.seq
, frag
);
1071 dtls1_hm_fragment_free(frag
);
1076 fprintf( stderr
, "buffered messge: \ttype = %xx\n", msg_buf
->type
);
1077 fprintf( stderr
, "\t\t\t\t\tlen = %d\n", msg_buf
->len
);
1078 fprintf( stderr
, "\t\t\t\t\tseq_num = %d\n", msg_buf
->seq_num
);
1081 pqueue_insert(s
->d1
->sent_messages
, item
);
1086 dtls1_retransmit_message(SSL
*s
, unsigned short seq
, unsigned long frag_off
,
1090 /* XDTLS: for now assuming that read/writes are blocking */
1093 unsigned long header_length
;
1096 OPENSSL_assert(s->init_num == 0);
1097 OPENSSL_assert(s->init_off == 0);
1100 /* XDTLS: the requested message ought to be found, otherwise error */
1101 item
= pqueue_find(s
->d1
->sent_messages
, seq
);
1104 fprintf(stderr
, "retransmit: message %d non-existant\n", seq
);
1110 frag
= (hm_fragment
*)item
->data
;
1112 if ( frag
->msg_header
.is_ccs
)
1113 header_length
= DTLS1_CCS_HEADER_LENGTH
;
1115 header_length
= DTLS1_HM_HEADER_LENGTH
;
1117 memcpy(s
->init_buf
->data
, frag
->fragment
,
1118 frag
->msg_header
.msg_len
+ header_length
);
1119 s
->init_num
= frag
->msg_header
.msg_len
+ header_length
;
1121 dtls1_set_message_header_int(s
, frag
->msg_header
.type
,
1122 frag
->msg_header
.msg_len
, frag
->msg_header
.seq
, 0,
1123 frag
->msg_header
.frag_len
);
1125 s
->d1
->retransmitting
= 1;
1126 ret
= dtls1_do_write(s
, frag
->msg_header
.is_ccs
?
1127 SSL3_RT_CHANGE_CIPHER_SPEC
: SSL3_RT_HANDSHAKE
);
1128 s
->d1
->retransmitting
= 0;
1130 BIO_flush(SSL_get_wbio(s
));
1134 /* call this function when the buffered messages are no longer needed */
1136 dtls1_clear_record_buffer(SSL
*s
)
1140 for(item
= pqueue_pop(s
->d1
->sent_messages
);
1141 item
!= NULL
; item
= pqueue_pop(s
->d1
->sent_messages
))
1143 dtls1_hm_fragment_free((hm_fragment
*)item
->data
);
1150 dtls1_set_message_header(SSL
*s
, unsigned char *p
, unsigned char mt
,
1151 unsigned long len
, unsigned long frag_off
, unsigned long frag_len
)
1155 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
1156 s
->d1
->next_handshake_write_seq
++;
1159 dtls1_set_message_header_int(s
, mt
, len
, s
->d1
->handshake_write_seq
,
1160 frag_off
, frag_len
);
1162 return p
+= DTLS1_HM_HEADER_LENGTH
;
1166 /* don't actually do the writing, wait till the MTU has been retrieved */
1168 dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
1169 unsigned long len
, unsigned short seq_num
, unsigned long frag_off
,
1170 unsigned long frag_len
)
1172 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1175 msg_hdr
->msg_len
= len
;
1176 msg_hdr
->seq
= seq_num
;
1177 msg_hdr
->frag_off
= frag_off
;
1178 msg_hdr
->frag_len
= frag_len
;
1182 dtls1_fix_message_header(SSL
*s
, unsigned long frag_off
,
1183 unsigned long frag_len
)
1185 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1187 msg_hdr
->frag_off
= frag_off
;
1188 msg_hdr
->frag_len
= frag_len
;
1191 static unsigned char *
1192 dtls1_write_message_header(SSL
*s
, unsigned char *p
)
1194 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1196 *p
++ = msg_hdr
->type
;
1197 l2n3(msg_hdr
->msg_len
, p
);
1199 s2n(msg_hdr
->seq
, p
);
1200 l2n3(msg_hdr
->frag_off
, p
);
1201 l2n3(msg_hdr
->frag_len
, p
);
1210 g_probable_mtu
[(sizeof(g_probable_mtu
) /
1211 sizeof(g_probable_mtu
[0])) - 1];
1215 dtls1_guess_mtu(unsigned int curr_mtu
)
1219 if ( curr_mtu
== 0 )
1220 return g_probable_mtu
[0] ;
1222 for ( i
= 0; i
< sizeof(g_probable_mtu
)/sizeof(g_probable_mtu
[0]); i
++)
1223 if ( curr_mtu
> g_probable_mtu
[i
])
1224 return g_probable_mtu
[i
];
1230 dtls1_get_message_header(unsigned char *data
, struct hm_header_st
*msg_hdr
)
1232 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
1233 msg_hdr
->type
= *(data
++);
1234 n2l3(data
, msg_hdr
->msg_len
);
1236 n2s(data
, msg_hdr
->seq
);
1237 n2l3(data
, msg_hdr
->frag_off
);
1238 n2l3(data
, msg_hdr
->frag_len
);
1242 dtls1_get_ccs_header(unsigned char *data
, struct ccs_header_st
*ccs_hdr
)
1244 memset(ccs_hdr
, 0x00, sizeof(struct ccs_header_st
));
1246 ccs_hdr
->type
= *(data
++);
1247 n2s(data
, ccs_hdr
->seq
);