3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
6 /* ====================================================================
7 * Copyright (c) 1998-2018 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>
126 #define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8)
128 #define RSMBLY_BITMASK_MARK(bitmask, start, end) { \
129 if ((end) - (start) <= 8) { \
131 for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \
134 bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \
135 for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \
136 bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \
139 #define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \
141 OPENSSL_assert((msg_len) > 0); \
143 if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \
144 if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \
145 if (bitmask[ii] != 0xff) { is_complete = 0; break; } }
148 # define RSMBLY_BITMASK_PRINT(bitmask, msg_len) { \
150 printf("bitmask: "); for (ii = 0; ii < (msg_len); ii++) \
151 printf("%d ", (bitmask[ii >> 3] & (1 << (ii & 7))) >> (ii & 7)); \
155 static unsigned char bitmask_start_values
[] =
156 { 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 };
157 static unsigned char bitmask_end_values
[] =
158 { 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f };
160 /* XDTLS: figure out the right values */
161 static const unsigned int g_probable_mtu
[] = { 1500, 512, 256 };
163 static void dtls1_fix_message_header(SSL
*s
, unsigned long frag_off
,
164 unsigned long frag_len
);
165 static unsigned char *dtls1_write_message_header(SSL
*s
, unsigned char *p
);
166 static void dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
168 unsigned short seq_num
,
169 unsigned long frag_off
,
170 unsigned long frag_len
);
171 static long dtls1_get_message_fragment(SSL
*s
, int st1
, int stn
, long max
,
174 static hm_fragment
*dtls1_hm_fragment_new(unsigned long frag_len
,
177 hm_fragment
*frag
= NULL
;
178 unsigned char *buf
= NULL
;
179 unsigned char *bitmask
= NULL
;
181 frag
= (hm_fragment
*)OPENSSL_malloc(sizeof(hm_fragment
));
186 buf
= (unsigned char *)OPENSSL_malloc(frag_len
);
193 /* zero length fragment gets zero frag->fragment */
194 frag
->fragment
= buf
;
196 /* Initialize reassembly bitmask if necessary */
199 (unsigned char *)OPENSSL_malloc(RSMBLY_BITMASK_SIZE(frag_len
));
200 if (bitmask
== NULL
) {
206 memset(bitmask
, 0, RSMBLY_BITMASK_SIZE(frag_len
));
209 frag
->reassembly
= bitmask
;
214 void dtls1_hm_fragment_free(hm_fragment
*frag
)
217 if (frag
->msg_header
.is_ccs
) {
218 EVP_CIPHER_CTX_free(frag
->msg_header
.
219 saved_retransmit_state
.enc_write_ctx
);
220 EVP_MD_CTX_destroy(frag
->msg_header
.
221 saved_retransmit_state
.write_hash
);
224 OPENSSL_free(frag
->fragment
);
225 if (frag
->reassembly
)
226 OPENSSL_free(frag
->reassembly
);
230 static int dtls1_query_mtu(SSL
*s
)
232 if (s
->d1
->link_mtu
) {
234 s
->d1
->link_mtu
- BIO_dgram_get_mtu_overhead(SSL_get_wbio(s
));
238 /* AHA! Figure out the MTU, and stick to the right size */
239 if (s
->d1
->mtu
< dtls1_min_mtu(s
)) {
240 if (!(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
242 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_QUERY_MTU
, 0, NULL
);
245 * I've seen the kernel return bogus numbers when it doesn't know
246 * (initial write), so just make sure we have a reasonable number
248 if (s
->d1
->mtu
< dtls1_min_mtu(s
)) {
250 s
->d1
->mtu
= dtls1_min_mtu(s
);
251 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SET_MTU
,
261 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or
262 * SSL3_RT_CHANGE_CIPHER_SPEC)
264 int dtls1_do_write(SSL
*s
, int type
)
267 unsigned int curr_mtu
;
269 unsigned int len
, frag_off
, mac_size
, blocksize
, used_len
;
271 if (!dtls1_query_mtu(s
))
274 OPENSSL_assert(s
->d1
->mtu
>= dtls1_min_mtu(s
)); /* should have something
277 if (s
->init_off
== 0 && type
== SSL3_RT_HANDSHAKE
)
278 OPENSSL_assert(s
->init_num
==
279 (int)s
->d1
->w_msg_hdr
.msg_len
+
280 DTLS1_HM_HEADER_LENGTH
);
284 && EVP_CIPHER_CTX_mode(s
->enc_write_ctx
) == EVP_CIPH_GCM_MODE
)
287 mac_size
= EVP_MD_CTX_size(s
->write_hash
);
291 if (s
->enc_write_ctx
&&
292 (EVP_CIPHER_CTX_mode(s
->enc_write_ctx
) == EVP_CIPH_CBC_MODE
))
293 blocksize
= 2 * EVP_CIPHER_block_size(s
->enc_write_ctx
->cipher
);
298 s
->rwstate
= SSL_NOTHING
;
300 /* s->init_num shouldn't ever be < 0...but just in case */
301 while (s
->init_num
> 0) {
302 if (type
== SSL3_RT_HANDSHAKE
&& s
->init_off
!= 0) {
303 /* We must be writing a fragment other than the first one */
306 /* This is the first attempt at writing out this fragment */
308 if (s
->init_off
<= DTLS1_HM_HEADER_LENGTH
) {
310 * Each fragment that was already sent must at least have
311 * contained the message header plus one other byte.
312 * Therefore |init_off| must have progressed by at least
313 * |DTLS1_HM_HEADER_LENGTH + 1| bytes. If not something went
320 * Adjust |init_off| and |init_num| to allow room for a new
321 * message header for this fragment.
323 s
->init_off
-= DTLS1_HM_HEADER_LENGTH
;
324 s
->init_num
+= DTLS1_HM_HEADER_LENGTH
;
327 * We must have been called again after a retry so use the
328 * fragment offset from our last attempt. We do not need
329 * to adjust |init_off| and |init_num| as above, because
330 * that should already have been done before the retry.
332 frag_off
= s
->d1
->w_msg_hdr
.frag_off
;
336 used_len
= BIO_wpending(SSL_get_wbio(s
)) + DTLS1_RT_HEADER_LENGTH
337 + mac_size
+ blocksize
;
338 if (s
->d1
->mtu
> used_len
)
339 curr_mtu
= s
->d1
->mtu
- used_len
;
343 if (curr_mtu
<= DTLS1_HM_HEADER_LENGTH
) {
345 * grr.. we could get an error if MTU picked was wrong
347 ret
= BIO_flush(SSL_get_wbio(s
));
349 s
->rwstate
= SSL_WRITING
;
352 used_len
= DTLS1_RT_HEADER_LENGTH
+ mac_size
+ blocksize
;
353 if (s
->d1
->mtu
> used_len
+ DTLS1_HM_HEADER_LENGTH
) {
354 curr_mtu
= s
->d1
->mtu
- used_len
;
356 /* Shouldn't happen */
362 * We just checked that s->init_num > 0 so this cast should be safe
364 if (((unsigned int)s
->init_num
) > curr_mtu
)
369 /* Shouldn't ever happen */
374 * XDTLS: this function is too long. split out the CCS part
376 if (type
== SSL3_RT_HANDSHAKE
) {
377 if (len
< DTLS1_HM_HEADER_LENGTH
) {
379 * len is so small that we really can't do anything sensible
384 dtls1_fix_message_header(s
, frag_off
,
385 len
- DTLS1_HM_HEADER_LENGTH
);
387 dtls1_write_message_header(s
,
388 (unsigned char *)&s
->init_buf
->
392 ret
= dtls1_write_bytes(s
, type
, &s
->init_buf
->data
[s
->init_off
],
396 * might need to update MTU here, but we don't know which
397 * previous packet caused the failure -- so can't really
398 * retransmit anything. continue as if everything is fine and
399 * wait for an alert to handle the retransmit
401 if (retry
&& BIO_ctrl(SSL_get_wbio(s
),
402 BIO_CTRL_DGRAM_MTU_EXCEEDED
, 0, NULL
) > 0) {
403 if (!(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
404 if (!dtls1_query_mtu(s
))
406 /* Have one more go */
416 * bad if this assert fails, only part of the handshake message
417 * got sent. but why would this happen?
419 OPENSSL_assert(len
== (unsigned int)ret
);
421 if (type
== SSL3_RT_HANDSHAKE
&& !s
->d1
->retransmitting
) {
423 * should not be done for 'Hello Request's, but in that case
424 * we'll ignore the result anyway
427 (unsigned char *)&s
->init_buf
->data
[s
->init_off
];
428 const struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
431 if (frag_off
== 0 && s
->version
!= DTLS1_BAD_VER
) {
433 * reconstruct message header is if it is being sent in
436 *p
++ = msg_hdr
->type
;
437 l2n3(msg_hdr
->msg_len
, p
);
438 s2n(msg_hdr
->seq
, p
);
440 l2n3(msg_hdr
->msg_len
, p
);
441 p
-= DTLS1_HM_HEADER_LENGTH
;
444 p
+= DTLS1_HM_HEADER_LENGTH
;
445 xlen
= ret
- DTLS1_HM_HEADER_LENGTH
;
448 ssl3_finish_mac(s
, p
, xlen
);
451 if (ret
== s
->init_num
) {
453 s
->msg_callback(1, s
->version
, type
, s
->init_buf
->data
,
454 (size_t)(s
->init_off
+ s
->init_num
), s
,
455 s
->msg_callback_arg
);
457 s
->init_off
= 0; /* done writing this message */
464 ret
-= DTLS1_HM_HEADER_LENGTH
;
468 * We save the fragment offset for the next fragment so we have it
469 * available in case of an IO retry. We don't know the length of the
470 * next fragment yet so just set that to 0 for now. It will be
471 * updated again later.
473 dtls1_fix_message_header(s
, frag_off
, 0);
480 * Obtain handshake message of message type 'mt' (any if mt == -1), maximum
481 * acceptable body length 'max'. Read an entire handshake message. Handshake
482 * messages arrive in fragments.
484 long dtls1_get_message(SSL
*s
, int st1
, int stn
, int mt
, long max
, int *ok
)
487 struct hm_header_st
*msg_hdr
;
489 unsigned long msg_len
;
492 * s3->tmp is used to store messages that are unexpected, caused by the
493 * absence of an optional handshake message
495 if (s
->s3
->tmp
.reuse_message
) {
496 s
->s3
->tmp
.reuse_message
= 0;
497 if ((mt
>= 0) && (s
->s3
->tmp
.message_type
!= mt
)) {
498 al
= SSL_AD_UNEXPECTED_MESSAGE
;
499 SSLerr(SSL_F_DTLS1_GET_MESSAGE
, SSL_R_UNEXPECTED_MESSAGE
);
503 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
504 s
->init_num
= (int)s
->s3
->tmp
.message_size
;
508 msg_hdr
= &s
->d1
->r_msg_hdr
;
509 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
512 i
= dtls1_get_message_fragment(s
, st1
, stn
, max
, ok
);
513 if (i
== DTLS1_HM_BAD_FRAGMENT
|| i
== DTLS1_HM_FRAGMENT_RETRY
) {
514 /* bad fragment received */
516 } else if (i
<= 0 && !*ok
) {
521 * Don't change the *message* read sequence number while listening. For
522 * the *record* write sequence we reflect the ClientHello sequence number
526 memcpy(s
->s3
->write_sequence
, s
->s3
->read_sequence
,
527 sizeof(s
->s3
->write_sequence
));
529 s
->d1
->handshake_read_seq
++;
531 if (mt
>= 0 && s
->s3
->tmp
.message_type
!= mt
) {
532 al
= SSL_AD_UNEXPECTED_MESSAGE
;
533 SSLerr(SSL_F_DTLS1_GET_MESSAGE
, SSL_R_UNEXPECTED_MESSAGE
);
537 p
= (unsigned char *)s
->init_buf
->data
;
538 msg_len
= msg_hdr
->msg_len
;
540 /* reconstruct message header */
541 *(p
++) = msg_hdr
->type
;
543 s2n(msg_hdr
->seq
, p
);
546 if (s
->version
!= DTLS1_BAD_VER
) {
547 p
-= DTLS1_HM_HEADER_LENGTH
;
548 msg_len
+= DTLS1_HM_HEADER_LENGTH
;
551 ssl3_finish_mac(s
, p
, msg_len
);
553 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
554 p
, msg_len
, s
, s
->msg_callback_arg
);
556 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
558 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
562 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
567 static int dtls1_preprocess_fragment(SSL
*s
, struct hm_header_st
*msg_hdr
,
570 size_t frag_off
, frag_len
, msg_len
;
572 msg_len
= msg_hdr
->msg_len
;
573 frag_off
= msg_hdr
->frag_off
;
574 frag_len
= msg_hdr
->frag_len
;
576 /* sanity checking */
577 if ((frag_off
+ frag_len
) > msg_len
) {
578 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
579 return SSL_AD_ILLEGAL_PARAMETER
;
582 if ((frag_off
+ frag_len
) > (unsigned long)max
) {
583 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
584 return SSL_AD_ILLEGAL_PARAMETER
;
587 if (s
->d1
->r_msg_hdr
.frag_off
== 0) { /* first fragment */
589 * msg_len is limited to 2^24, but is effectively checked against max
592 * Make buffer slightly larger than message length as a precaution
593 * against small OOB reads e.g. CVE-2016-6306
595 if (!BUF_MEM_grow_clean
596 (s
->init_buf
, msg_len
+ DTLS1_HM_HEADER_LENGTH
+ 16)) {
597 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, ERR_R_BUF_LIB
);
598 return SSL_AD_INTERNAL_ERROR
;
601 s
->s3
->tmp
.message_size
= msg_len
;
602 s
->d1
->r_msg_hdr
.msg_len
= msg_len
;
603 s
->s3
->tmp
.message_type
= msg_hdr
->type
;
604 s
->d1
->r_msg_hdr
.type
= msg_hdr
->type
;
605 s
->d1
->r_msg_hdr
.seq
= msg_hdr
->seq
;
606 } else if (msg_len
!= s
->d1
->r_msg_hdr
.msg_len
) {
608 * They must be playing with us! BTW, failure to enforce upper limit
609 * would open possibility for buffer overrun.
611 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
612 return SSL_AD_ILLEGAL_PARAMETER
;
615 return 0; /* no error */
618 static int dtls1_retrieve_buffered_fragment(SSL
*s
, long max
, int *ok
)
621 * (0) check whether the desired fragment is available
623 * (1) copy over the fragment to s->init_buf->data[]
624 * (2) update s->init_num
632 item
= pqueue_peek(s
->d1
->buffered_messages
);
636 frag
= (hm_fragment
*)item
->data
;
638 if (frag
->msg_header
.seq
< s
->d1
->handshake_read_seq
) {
639 /* This is a stale message that has been buffered so clear it */
640 pqueue_pop(s
->d1
->buffered_messages
);
641 dtls1_hm_fragment_free(frag
);
646 } while (item
== NULL
);
649 /* Don't return if reassembly still in progress */
650 if (frag
->reassembly
!= NULL
)
653 if (s
->d1
->handshake_read_seq
== frag
->msg_header
.seq
) {
654 unsigned long frag_len
= frag
->msg_header
.frag_len
;
655 pqueue_pop(s
->d1
->buffered_messages
);
657 al
= dtls1_preprocess_fragment(s
, &frag
->msg_header
, max
);
659 /* al will be 0 if no alert */
660 if (al
== 0 && frag
->msg_header
.frag_len
> 0) {
662 (unsigned char *)s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
663 memcpy(&p
[frag
->msg_header
.frag_off
], frag
->fragment
,
664 frag
->msg_header
.frag_len
);
667 dtls1_hm_fragment_free(frag
);
675 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
684 * dtls1_max_handshake_message_len returns the maximum number of bytes
685 * permitted in a DTLS handshake message for |s|. The minimum is 16KB, but
686 * may be greater if the maximum certificate list size requires it.
688 static unsigned long dtls1_max_handshake_message_len(const SSL
*s
)
690 unsigned long max_len
=
691 DTLS1_HM_HEADER_LENGTH
+ SSL3_RT_MAX_ENCRYPTED_LENGTH
;
692 if (max_len
< (unsigned long)s
->max_cert_list
)
693 return s
->max_cert_list
;
698 dtls1_reassemble_fragment(SSL
*s
, const struct hm_header_st
*msg_hdr
, int *ok
)
700 hm_fragment
*frag
= NULL
;
702 int i
= -1, is_complete
;
703 unsigned char seq64be
[8];
704 unsigned long frag_len
= msg_hdr
->frag_len
;
706 if ((msg_hdr
->frag_off
+ frag_len
) > msg_hdr
->msg_len
||
707 msg_hdr
->msg_len
> dtls1_max_handshake_message_len(s
))
711 return DTLS1_HM_FRAGMENT_RETRY
;
713 /* Try to find item in queue */
714 memset(seq64be
, 0, sizeof(seq64be
));
715 seq64be
[6] = (unsigned char)(msg_hdr
->seq
>> 8);
716 seq64be
[7] = (unsigned char)msg_hdr
->seq
;
717 item
= pqueue_find(s
->d1
->buffered_messages
, seq64be
);
720 frag
= dtls1_hm_fragment_new(msg_hdr
->msg_len
, 1);
723 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
724 frag
->msg_header
.frag_len
= frag
->msg_header
.msg_len
;
725 frag
->msg_header
.frag_off
= 0;
727 frag
= (hm_fragment
*)item
->data
;
728 if (frag
->msg_header
.msg_len
!= msg_hdr
->msg_len
) {
736 * If message is already reassembled, this must be a retransmit and can
737 * be dropped. In this case item != NULL and so frag does not need to be
740 if (frag
->reassembly
== NULL
) {
741 unsigned char devnull
[256];
744 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
747 sizeof(devnull
) ? sizeof(devnull
) :
753 return DTLS1_HM_FRAGMENT_RETRY
;
756 /* read the body of the fragment (header has already been read */
757 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
758 frag
->fragment
+ msg_hdr
->frag_off
,
760 if ((unsigned long)i
!= frag_len
)
765 RSMBLY_BITMASK_MARK(frag
->reassembly
, (long)msg_hdr
->frag_off
,
766 (long)(msg_hdr
->frag_off
+ frag_len
));
768 RSMBLY_BITMASK_IS_COMPLETE(frag
->reassembly
, (long)msg_hdr
->msg_len
,
772 OPENSSL_free(frag
->reassembly
);
773 frag
->reassembly
= NULL
;
777 item
= pitem_new(seq64be
, frag
);
783 item
= pqueue_insert(s
->d1
->buffered_messages
, item
);
785 * pqueue_insert fails iff a duplicate item is inserted. However,
786 * |item| cannot be a duplicate. If it were, |pqueue_find|, above,
787 * would have returned it and control would never have reached this
790 OPENSSL_assert(item
!= NULL
);
793 return DTLS1_HM_FRAGMENT_RETRY
;
796 if (frag
!= NULL
&& item
== NULL
)
797 dtls1_hm_fragment_free(frag
);
803 dtls1_process_out_of_seq_message(SSL
*s
, const struct hm_header_st
*msg_hdr
,
807 hm_fragment
*frag
= NULL
;
809 unsigned char seq64be
[8];
810 unsigned long frag_len
= msg_hdr
->frag_len
;
812 if ((msg_hdr
->frag_off
+ frag_len
) > msg_hdr
->msg_len
)
815 /* Try to find item in queue, to prevent duplicate entries */
816 memset(seq64be
, 0, sizeof(seq64be
));
817 seq64be
[6] = (unsigned char)(msg_hdr
->seq
>> 8);
818 seq64be
[7] = (unsigned char)msg_hdr
->seq
;
819 item
= pqueue_find(s
->d1
->buffered_messages
, seq64be
);
822 * If we already have an entry and this one is a fragment, don't discard
823 * it and rather try to reassemble it.
825 if (item
!= NULL
&& frag_len
!= msg_hdr
->msg_len
)
829 * Discard the message if sequence number was already there, is too far
830 * in the future, already in the queue or if we received a FINISHED
831 * before the SERVER_HELLO, which then must be a stale retransmit.
833 if (msg_hdr
->seq
<= s
->d1
->handshake_read_seq
||
834 msg_hdr
->seq
> s
->d1
->handshake_read_seq
+ 10 || item
!= NULL
||
835 (s
->d1
->handshake_read_seq
== 0 && msg_hdr
->type
== SSL3_MT_FINISHED
))
837 unsigned char devnull
[256];
840 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
843 sizeof(devnull
) ? sizeof(devnull
) :
850 if (frag_len
!= msg_hdr
->msg_len
)
851 return dtls1_reassemble_fragment(s
, msg_hdr
, ok
);
853 if (frag_len
> dtls1_max_handshake_message_len(s
))
856 frag
= dtls1_hm_fragment_new(frag_len
, 0);
860 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
864 * read the body of the fragment (header has already been read
866 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
867 frag
->fragment
, frag_len
, 0);
868 if ((unsigned long)i
!= frag_len
)
874 item
= pitem_new(seq64be
, frag
);
878 item
= pqueue_insert(s
->d1
->buffered_messages
, item
);
880 * pqueue_insert fails iff a duplicate item is inserted. However,
881 * |item| cannot be a duplicate. If it were, |pqueue_find|, above,
882 * would have returned it. Then, either |frag_len| !=
883 * |msg_hdr->msg_len| in which case |item| is set to NULL and it will
884 * have been processed with |dtls1_reassemble_fragment|, above, or
885 * the record will have been discarded.
887 OPENSSL_assert(item
!= NULL
);
890 return DTLS1_HM_FRAGMENT_RETRY
;
893 if (frag
!= NULL
&& item
== NULL
)
894 dtls1_hm_fragment_free(frag
);
900 dtls1_get_message_fragment(SSL
*s
, int st1
, int stn
, long max
, int *ok
)
902 unsigned char wire
[DTLS1_HM_HEADER_LENGTH
];
903 unsigned long len
, frag_off
, frag_len
;
905 struct hm_header_st msg_hdr
;
908 /* see if we have the required fragment already */
909 if ((frag_len
= dtls1_retrieve_buffered_fragment(s
, max
, ok
)) || *ok
) {
911 s
->init_num
= frag_len
;
915 /* read handshake message header */
916 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, wire
,
917 DTLS1_HM_HEADER_LENGTH
, 0);
918 if (i
<= 0) { /* nbio, or an error */
919 s
->rwstate
= SSL_READING
;
923 /* Handshake fails if message header is incomplete */
924 if (i
!= DTLS1_HM_HEADER_LENGTH
) {
925 al
= SSL_AD_UNEXPECTED_MESSAGE
;
926 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
, SSL_R_UNEXPECTED_MESSAGE
);
930 /* parse the message fragment header */
931 dtls1_get_message_header(wire
, &msg_hdr
);
933 len
= msg_hdr
.msg_len
;
934 frag_off
= msg_hdr
.frag_off
;
935 frag_len
= msg_hdr
.frag_len
;
938 * We must have at least frag_len bytes left in the record to be read.
939 * Fragments must not span records.
941 if (frag_len
> s
->s3
->rrec
.length
) {
942 al
= SSL3_AD_ILLEGAL_PARAMETER
;
943 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
, SSL_R_BAD_LENGTH
);
948 * if this is a future (or stale) message it gets buffered
949 * (or dropped)--no further processing at this time
950 * While listening, we accept seq 1 (ClientHello with cookie)
951 * although we're still expecting seq 0 (ClientHello)
953 if (msg_hdr
.seq
!= s
->d1
->handshake_read_seq
954 && !(s
->d1
->listen
&& msg_hdr
.seq
== 1))
955 return dtls1_process_out_of_seq_message(s
, &msg_hdr
, ok
);
957 if (frag_len
&& frag_len
< len
)
958 return dtls1_reassemble_fragment(s
, &msg_hdr
, ok
);
960 if (!s
->server
&& s
->d1
->r_msg_hdr
.frag_off
== 0 &&
961 wire
[0] == SSL3_MT_HELLO_REQUEST
) {
963 * The server may always send 'Hello Request' messages -- we are
964 * doing a handshake anyway now, so ignore them if their format is
965 * correct. Does not count for 'Finished' MAC.
967 if (wire
[1] == 0 && wire
[2] == 0 && wire
[3] == 0) {
969 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
970 wire
, DTLS1_HM_HEADER_LENGTH
, s
,
971 s
->msg_callback_arg
);
975 } else { /* Incorrectly formated Hello request */
977 al
= SSL_AD_UNEXPECTED_MESSAGE
;
978 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
,
979 SSL_R_UNEXPECTED_MESSAGE
);
984 if ((al
= dtls1_preprocess_fragment(s
, &msg_hdr
, max
)))
989 (unsigned char *)s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
991 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
992 &p
[frag_off
], frag_len
, 0);
995 * This shouldn't ever fail due to NBIO because we already checked
996 * that we have enough data in the record
999 s
->rwstate
= SSL_READING
;
1007 * XDTLS: an incorrectly formatted fragment should cause the handshake
1010 if (i
!= (int)frag_len
) {
1011 al
= SSL3_AD_ILLEGAL_PARAMETER
;
1012 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
, SSL3_AD_ILLEGAL_PARAMETER
);
1020 * Note that s->init_num is *not* used as current offset in
1021 * s->init_buf->data, but as a counter summing up fragments' lengths: as
1022 * soon as they sum up to handshake packet length, we assume we have got
1023 * all the fragments.
1025 s
->init_num
= frag_len
;
1029 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
1037 * for these 2 messages, we need to
1038 * ssl->enc_read_ctx re-init
1039 * ssl->s3->read_sequence zero
1040 * ssl->s3->read_mac_secret re-init
1041 * ssl->session->read_sym_enc assign
1042 * ssl->session->read_compression assign
1043 * ssl->session->read_hash assign
1045 int dtls1_send_change_cipher_spec(SSL
*s
, int a
, int b
)
1049 if (s
->state
== a
) {
1050 p
= (unsigned char *)s
->init_buf
->data
;
1052 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
1053 s
->init_num
= DTLS1_CCS_HEADER_LENGTH
;
1055 if (s
->version
== DTLS1_BAD_VER
) {
1056 s
->d1
->next_handshake_write_seq
++;
1057 s2n(s
->d1
->handshake_write_seq
, p
);
1063 dtls1_set_message_header_int(s
, SSL3_MT_CCS
, 0,
1064 s
->d1
->handshake_write_seq
, 0, 0);
1066 /* buffer the message to handle re-xmits */
1067 dtls1_buffer_message(s
, 1);
1072 /* SSL3_ST_CW_CHANGE_B */
1073 return (dtls1_do_write(s
, SSL3_RT_CHANGE_CIPHER_SPEC
));
1076 int dtls1_read_failed(SSL
*s
, int code
)
1080 fprintf(stderr
, "invalid state reached %s:%d", __FILE__
, __LINE__
);
1085 if (!dtls1_is_timer_expired(s
)) {
1087 * not a timeout, none of our business, let higher layers handle
1088 * this. in fact it's probably an error
1092 #ifndef OPENSSL_NO_HEARTBEATS
1093 /* done, no need to send a retransmit */
1094 if (!SSL_in_init(s
) && !s
->tlsext_hb_pending
)
1096 /* done, no need to send a retransmit */
1097 if (!SSL_in_init(s
))
1100 BIO_set_flags(SSL_get_rbio(s
), BIO_FLAGS_READ
);
1103 #if 0 /* for now, each alert contains only one
1105 item
= pqueue_peek(state
->rcvd_records
);
1107 /* send an alert immediately for all the missing records */
1111 #if 0 /* no more alert sending, just retransmit the
1112 * last set of messages */
1113 if (state
->timeout
.read_timeouts
>= DTLS1_TMO_READ_COUNT
)
1114 ssl3_send_alert(s
, SSL3_AL_WARNING
,
1115 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
);
1118 return dtls1_handle_timeout(s
);
1121 int dtls1_get_queue_priority(unsigned short seq
, int is_ccs
)
1124 * The index of the retransmission queue actually is the message sequence
1125 * number, since the queue only contains messages of a single handshake.
1126 * However, the ChangeCipherSpec has no message sequence number and so
1127 * using only the sequence will result in the CCS and Finished having the
1128 * same index. To prevent this, the sequence number is multiplied by 2.
1129 * In case of a CCS 1 is subtracted. This does not only differ CSS and
1130 * Finished, it also maintains the order of the index (important for
1131 * priority queues) and fits in the unsigned short variable.
1133 return seq
* 2 - is_ccs
;
1136 int dtls1_retransmit_buffered_messages(SSL
*s
)
1138 pqueue sent
= s
->d1
->sent_messages
;
1144 iter
= pqueue_iterator(sent
);
1146 for (item
= pqueue_next(&iter
); item
!= NULL
; item
= pqueue_next(&iter
)) {
1147 frag
= (hm_fragment
*)item
->data
;
1148 if (dtls1_retransmit_message(s
, (unsigned short)
1149 dtls1_get_queue_priority
1150 (frag
->msg_header
.seq
,
1151 frag
->msg_header
.is_ccs
), 0,
1152 &found
) <= 0 && found
) {
1154 fprintf(stderr
, "dtls1_retransmit_message() failed\n");
1163 int dtls1_buffer_message(SSL
*s
, int is_ccs
)
1167 unsigned char seq64be
[8];
1170 * this function is called immediately after a message has been
1173 OPENSSL_assert(s
->init_off
== 0);
1175 frag
= dtls1_hm_fragment_new(s
->init_num
, 0);
1179 memcpy(frag
->fragment
, s
->init_buf
->data
, s
->init_num
);
1182 /* For DTLS1_BAD_VER the header length is non-standard */
1183 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
1184 ((s
->version
==DTLS1_BAD_VER
)?3:DTLS1_CCS_HEADER_LENGTH
)
1185 == (unsigned int)s
->init_num
);
1187 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
1188 DTLS1_HM_HEADER_LENGTH
== (unsigned int)s
->init_num
);
1191 frag
->msg_header
.msg_len
= s
->d1
->w_msg_hdr
.msg_len
;
1192 frag
->msg_header
.seq
= s
->d1
->w_msg_hdr
.seq
;
1193 frag
->msg_header
.type
= s
->d1
->w_msg_hdr
.type
;
1194 frag
->msg_header
.frag_off
= 0;
1195 frag
->msg_header
.frag_len
= s
->d1
->w_msg_hdr
.msg_len
;
1196 frag
->msg_header
.is_ccs
= is_ccs
;
1198 /* save current state */
1199 frag
->msg_header
.saved_retransmit_state
.enc_write_ctx
= s
->enc_write_ctx
;
1200 frag
->msg_header
.saved_retransmit_state
.write_hash
= s
->write_hash
;
1201 frag
->msg_header
.saved_retransmit_state
.compress
= s
->compress
;
1202 frag
->msg_header
.saved_retransmit_state
.session
= s
->session
;
1203 frag
->msg_header
.saved_retransmit_state
.epoch
= s
->d1
->w_epoch
;
1205 memset(seq64be
, 0, sizeof(seq64be
));
1208 char)(dtls1_get_queue_priority(frag
->msg_header
.seq
,
1209 frag
->msg_header
.is_ccs
) >> 8);
1212 char)(dtls1_get_queue_priority(frag
->msg_header
.seq
,
1213 frag
->msg_header
.is_ccs
));
1215 item
= pitem_new(seq64be
, frag
);
1217 dtls1_hm_fragment_free(frag
);
1221 fprintf(stderr
, "buffered messge: \ttype = %xx\n", msg_buf
->type
);
1222 fprintf(stderr
, "\t\t\t\t\tlen = %d\n", msg_buf
->len
);
1223 fprintf(stderr
, "\t\t\t\t\tseq_num = %d\n", msg_buf
->seq_num
);
1226 pqueue_insert(s
->d1
->sent_messages
, item
);
1231 dtls1_retransmit_message(SSL
*s
, unsigned short seq
, unsigned long frag_off
,
1235 /* XDTLS: for now assuming that read/writes are blocking */
1238 unsigned long header_length
;
1239 unsigned char seq64be
[8];
1240 struct dtls1_retransmit_state saved_state
;
1241 unsigned char save_write_sequence
[8] = {0, 0, 0, 0, 0, 0, 0, 0};
1244 OPENSSL_assert(s->init_num == 0);
1245 OPENSSL_assert(s->init_off == 0);
1248 /* XDTLS: the requested message ought to be found, otherwise error */
1249 memset(seq64be
, 0, sizeof(seq64be
));
1250 seq64be
[6] = (unsigned char)(seq
>> 8);
1251 seq64be
[7] = (unsigned char)seq
;
1253 item
= pqueue_find(s
->d1
->sent_messages
, seq64be
);
1256 fprintf(stderr
, "retransmit: message %d non-existant\n", seq
);
1263 frag
= (hm_fragment
*)item
->data
;
1265 if (frag
->msg_header
.is_ccs
)
1266 header_length
= DTLS1_CCS_HEADER_LENGTH
;
1268 header_length
= DTLS1_HM_HEADER_LENGTH
;
1270 memcpy(s
->init_buf
->data
, frag
->fragment
,
1271 frag
->msg_header
.msg_len
+ header_length
);
1272 s
->init_num
= frag
->msg_header
.msg_len
+ header_length
;
1274 dtls1_set_message_header_int(s
, frag
->msg_header
.type
,
1275 frag
->msg_header
.msg_len
,
1276 frag
->msg_header
.seq
, 0,
1277 frag
->msg_header
.frag_len
);
1279 /* save current state */
1280 saved_state
.enc_write_ctx
= s
->enc_write_ctx
;
1281 saved_state
.write_hash
= s
->write_hash
;
1282 saved_state
.compress
= s
->compress
;
1283 saved_state
.session
= s
->session
;
1284 saved_state
.epoch
= s
->d1
->w_epoch
;
1285 saved_state
.epoch
= s
->d1
->w_epoch
;
1287 s
->d1
->retransmitting
= 1;
1289 /* restore state in which the message was originally sent */
1290 s
->enc_write_ctx
= frag
->msg_header
.saved_retransmit_state
.enc_write_ctx
;
1291 s
->write_hash
= frag
->msg_header
.saved_retransmit_state
.write_hash
;
1292 s
->compress
= frag
->msg_header
.saved_retransmit_state
.compress
;
1293 s
->session
= frag
->msg_header
.saved_retransmit_state
.session
;
1294 s
->d1
->w_epoch
= frag
->msg_header
.saved_retransmit_state
.epoch
;
1296 if (frag
->msg_header
.saved_retransmit_state
.epoch
==
1297 saved_state
.epoch
- 1) {
1298 memcpy(save_write_sequence
, s
->s3
->write_sequence
,
1299 sizeof(s
->s3
->write_sequence
));
1300 memcpy(s
->s3
->write_sequence
, s
->d1
->last_write_sequence
,
1301 sizeof(s
->s3
->write_sequence
));
1304 ret
= dtls1_do_write(s
, frag
->msg_header
.is_ccs
?
1305 SSL3_RT_CHANGE_CIPHER_SPEC
: SSL3_RT_HANDSHAKE
);
1307 /* restore current state */
1308 s
->enc_write_ctx
= saved_state
.enc_write_ctx
;
1309 s
->write_hash
= saved_state
.write_hash
;
1310 s
->compress
= saved_state
.compress
;
1311 s
->session
= saved_state
.session
;
1312 s
->d1
->w_epoch
= saved_state
.epoch
;
1314 if (frag
->msg_header
.saved_retransmit_state
.epoch
==
1315 saved_state
.epoch
- 1) {
1316 memcpy(s
->d1
->last_write_sequence
, s
->s3
->write_sequence
,
1317 sizeof(s
->s3
->write_sequence
));
1318 memcpy(s
->s3
->write_sequence
, save_write_sequence
,
1319 sizeof(s
->s3
->write_sequence
));
1322 s
->d1
->retransmitting
= 0;
1324 (void)BIO_flush(SSL_get_wbio(s
));
1328 unsigned char *dtls1_set_message_header(SSL
*s
, unsigned char *p
,
1329 unsigned char mt
, unsigned long len
,
1330 unsigned long frag_off
,
1331 unsigned long frag_len
)
1333 /* Don't change sequence numbers while listening */
1334 if (frag_off
== 0 && !s
->d1
->listen
) {
1335 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
1336 s
->d1
->next_handshake_write_seq
++;
1339 dtls1_set_message_header_int(s
, mt
, len
, s
->d1
->handshake_write_seq
,
1340 frag_off
, frag_len
);
1342 return p
+= DTLS1_HM_HEADER_LENGTH
;
1345 /* don't actually do the writing, wait till the MTU has been retrieved */
1347 dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
1348 unsigned long len
, unsigned short seq_num
,
1349 unsigned long frag_off
, unsigned long frag_len
)
1351 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1354 msg_hdr
->msg_len
= len
;
1355 msg_hdr
->seq
= seq_num
;
1356 msg_hdr
->frag_off
= frag_off
;
1357 msg_hdr
->frag_len
= frag_len
;
1361 dtls1_fix_message_header(SSL
*s
, unsigned long frag_off
,
1362 unsigned long frag_len
)
1364 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1366 msg_hdr
->frag_off
= frag_off
;
1367 msg_hdr
->frag_len
= frag_len
;
1370 static unsigned char *dtls1_write_message_header(SSL
*s
, unsigned char *p
)
1372 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1374 *p
++ = msg_hdr
->type
;
1375 l2n3(msg_hdr
->msg_len
, p
);
1377 s2n(msg_hdr
->seq
, p
);
1378 l2n3(msg_hdr
->frag_off
, p
);
1379 l2n3(msg_hdr
->frag_len
, p
);
1384 unsigned int dtls1_link_min_mtu(void)
1386 return (g_probable_mtu
[(sizeof(g_probable_mtu
) /
1387 sizeof(g_probable_mtu
[0])) - 1]);
1390 unsigned int dtls1_min_mtu(SSL
*s
)
1392 return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s
));
1396 dtls1_get_message_header(unsigned char *data
, struct hm_header_st
*msg_hdr
)
1398 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
1399 msg_hdr
->type
= *(data
++);
1400 n2l3(data
, msg_hdr
->msg_len
);
1402 n2s(data
, msg_hdr
->seq
);
1403 n2l3(data
, msg_hdr
->frag_off
);
1404 n2l3(data
, msg_hdr
->frag_len
);
1407 void dtls1_get_ccs_header(unsigned char *data
, struct ccs_header_st
*ccs_hdr
)
1409 memset(ccs_hdr
, 0x00, sizeof(struct ccs_header_st
));
1411 ccs_hdr
->type
= *(data
++);
1414 int dtls1_shutdown(SSL
*s
)
1417 #ifndef OPENSSL_NO_SCTP
1420 wbio
= SSL_get_wbio(s
);
1421 if (wbio
!= NULL
&& BIO_dgram_is_sctp(wbio
) &&
1422 !(s
->shutdown
& SSL_SENT_SHUTDOWN
)) {
1423 ret
= BIO_dgram_sctp_wait_for_dry(wbio
);
1428 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN
, 1,
1432 ret
= ssl3_shutdown(s
);
1433 #ifndef OPENSSL_NO_SCTP
1434 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN
, 0, NULL
);
1439 #ifndef OPENSSL_NO_HEARTBEATS
1440 int dtls1_process_heartbeat(SSL
*s
)
1442 unsigned char *p
= &s
->s3
->rrec
.data
[0], *pl
;
1443 unsigned short hbtype
;
1444 unsigned int payload
;
1445 unsigned int padding
= 16; /* Use minimum padding */
1447 if (s
->msg_callback
)
1448 s
->msg_callback(0, s
->version
, TLS1_RT_HEARTBEAT
,
1449 &s
->s3
->rrec
.data
[0], s
->s3
->rrec
.length
,
1450 s
, s
->msg_callback_arg
);
1452 /* Read type and payload length first */
1453 if (1 + 2 + 16 > s
->s3
->rrec
.length
)
1454 return 0; /* silently discard */
1455 if (s
->s3
->rrec
.length
> SSL3_RT_MAX_PLAIN_LENGTH
)
1456 return 0; /* silently discard per RFC 6520 sec. 4 */
1460 if (1 + 2 + payload
+ 16 > s
->s3
->rrec
.length
)
1461 return 0; /* silently discard per RFC 6520 sec. 4 */
1464 if (hbtype
== TLS1_HB_REQUEST
) {
1465 unsigned char *buffer
, *bp
;
1466 unsigned int write_length
= 1 /* heartbeat type */ +
1467 2 /* heartbeat length */ +
1471 if (write_length
> SSL3_RT_MAX_PLAIN_LENGTH
)
1475 * Allocate memory for the response, size is 1 byte message type,
1476 * plus 2 bytes payload length, plus payload, plus padding
1478 buffer
= OPENSSL_malloc(write_length
);
1483 /* Enter response type, length and copy payload */
1484 *bp
++ = TLS1_HB_RESPONSE
;
1486 memcpy(bp
, pl
, payload
);
1488 /* Random padding */
1489 if (RAND_bytes(bp
, padding
) <= 0) {
1490 OPENSSL_free(buffer
);
1494 r
= dtls1_write_bytes(s
, TLS1_RT_HEARTBEAT
, buffer
, write_length
);
1496 if (r
>= 0 && s
->msg_callback
)
1497 s
->msg_callback(1, s
->version
, TLS1_RT_HEARTBEAT
,
1498 buffer
, write_length
, s
, s
->msg_callback_arg
);
1500 OPENSSL_free(buffer
);
1504 } else if (hbtype
== TLS1_HB_RESPONSE
) {
1508 * We only send sequence numbers (2 bytes unsigned int), and 16
1509 * random bytes, so we just try to read the sequence number
1513 if (payload
== 18 && seq
== s
->tlsext_hb_seq
) {
1514 dtls1_stop_timer(s
);
1516 s
->tlsext_hb_pending
= 0;
1523 int dtls1_heartbeat(SSL
*s
)
1525 unsigned char *buf
, *p
;
1527 unsigned int payload
= 18; /* Sequence number + random bytes */
1528 unsigned int padding
= 16; /* Use minimum padding */
1530 /* Only send if peer supports and accepts HB requests... */
1531 if (!(s
->tlsext_heartbeat
& SSL_TLSEXT_HB_ENABLED
) ||
1532 s
->tlsext_heartbeat
& SSL_TLSEXT_HB_DONT_SEND_REQUESTS
) {
1533 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT
);
1537 /* ...and there is none in flight yet... */
1538 if (s
->tlsext_hb_pending
) {
1539 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_TLS_HEARTBEAT_PENDING
);
1543 /* ...and no handshake in progress. */
1544 if (SSL_in_init(s
) || s
->in_handshake
) {
1545 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_UNEXPECTED_MESSAGE
);
1550 * Check if padding is too long, payload and padding must not exceed 2^14
1551 * - 3 = 16381 bytes in total.
1553 OPENSSL_assert(payload
+ padding
<= 16381);
1556 * Create HeartBeat message, we just use a sequence number
1557 * as payload to distuingish different messages and add
1558 * some random stuff.
1559 * - Message Type, 1 byte
1560 * - Payload Length, 2 bytes (unsigned int)
1561 * - Payload, the sequence number (2 bytes uint)
1562 * - Payload, random bytes (16 bytes uint)
1565 buf
= OPENSSL_malloc(1 + 2 + payload
+ padding
);
1570 *p
++ = TLS1_HB_REQUEST
;
1571 /* Payload length (18 bytes here) */
1573 /* Sequence number */
1574 s2n(s
->tlsext_hb_seq
, p
);
1575 /* 16 random bytes */
1576 if (RAND_bytes(p
, 16) <= 0)
1579 /* Random padding */
1580 if (RAND_bytes(p
, padding
) <= 0)
1583 ret
= dtls1_write_bytes(s
, TLS1_RT_HEARTBEAT
, buf
, 3 + payload
+ padding
);
1585 if (s
->msg_callback
)
1586 s
->msg_callback(1, s
->version
, TLS1_RT_HEARTBEAT
,
1587 buf
, 3 + payload
+ padding
,
1588 s
, s
->msg_callback_arg
);
1590 dtls1_start_timer(s
);
1591 s
->tlsext_hb_pending
= 1;