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>
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; } }
147 static unsigned char bitmask_start_values
[] =
148 { 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 };
149 static unsigned char bitmask_end_values
[] =
150 { 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f };
152 /* XDTLS: figure out the right values */
153 static const unsigned int g_probable_mtu
[] = { 1500, 512, 256 };
155 static void dtls1_fix_message_header(SSL
*s
, unsigned long frag_off
,
156 unsigned long frag_len
);
157 static unsigned char *dtls1_write_message_header(SSL
*s
, unsigned char *p
);
158 static void dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
160 unsigned short seq_num
,
161 unsigned long frag_off
,
162 unsigned long frag_len
);
163 static long dtls1_get_message_fragment(SSL
*s
, int st1
, int stn
, long max
,
166 static hm_fragment
*dtls1_hm_fragment_new(unsigned long frag_len
,
169 hm_fragment
*frag
= NULL
;
170 unsigned char *buf
= NULL
;
171 unsigned char *bitmask
= NULL
;
173 frag
= OPENSSL_malloc(sizeof(*frag
));
178 buf
= OPENSSL_malloc(frag_len
);
185 /* zero length fragment gets zero frag->fragment */
186 frag
->fragment
= buf
;
188 /* Initialize reassembly bitmask if necessary */
190 bitmask
= OPENSSL_malloc(RSMBLY_BITMASK_SIZE(frag_len
));
191 if (bitmask
== NULL
) {
196 memset(bitmask
, 0, RSMBLY_BITMASK_SIZE(frag_len
));
199 frag
->reassembly
= bitmask
;
204 void dtls1_hm_fragment_free(hm_fragment
*frag
)
208 if (frag
->msg_header
.is_ccs
) {
209 EVP_CIPHER_CTX_free(frag
->msg_header
.
210 saved_retransmit_state
.enc_write_ctx
);
211 EVP_MD_CTX_destroy(frag
->msg_header
.
212 saved_retransmit_state
.write_hash
);
214 OPENSSL_free(frag
->fragment
);
215 OPENSSL_free(frag
->reassembly
);
219 static int dtls1_query_mtu(SSL
*s
)
221 if (s
->d1
->link_mtu
) {
223 s
->d1
->link_mtu
- BIO_dgram_get_mtu_overhead(SSL_get_wbio(s
));
227 /* AHA! Figure out the MTU, and stick to the right size */
228 if (s
->d1
->mtu
< dtls1_min_mtu(s
)) {
229 if (!(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
231 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_QUERY_MTU
, 0, NULL
);
234 * I've seen the kernel return bogus numbers when it doesn't know
235 * (initial write), so just make sure we have a reasonable number
237 if (s
->d1
->mtu
< dtls1_min_mtu(s
)) {
239 s
->d1
->mtu
= dtls1_min_mtu(s
);
240 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SET_MTU
,
250 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or
251 * SSL3_RT_CHANGE_CIPHER_SPEC)
253 int dtls1_do_write(SSL
*s
, int type
)
256 unsigned int curr_mtu
;
258 unsigned int len
, frag_off
, mac_size
, blocksize
, used_len
;
260 if (!dtls1_query_mtu(s
))
263 OPENSSL_assert(s
->d1
->mtu
>= dtls1_min_mtu(s
)); /* should have something
266 if (s
->init_off
== 0 && type
== SSL3_RT_HANDSHAKE
)
267 OPENSSL_assert(s
->init_num
==
268 (int)s
->d1
->w_msg_hdr
.msg_len
+
269 DTLS1_HM_HEADER_LENGTH
);
273 && EVP_CIPHER_CTX_mode(s
->enc_write_ctx
) == EVP_CIPH_GCM_MODE
)
276 mac_size
= EVP_MD_CTX_size(s
->write_hash
);
280 if (s
->enc_write_ctx
&&
281 (EVP_CIPHER_CTX_mode(s
->enc_write_ctx
) == EVP_CIPH_CBC_MODE
))
282 blocksize
= 2 * EVP_CIPHER_block_size(s
->enc_write_ctx
->cipher
);
287 /* s->init_num shouldn't ever be < 0...but just in case */
288 while (s
->init_num
> 0) {
289 used_len
= BIO_wpending(SSL_get_wbio(s
)) + DTLS1_RT_HEADER_LENGTH
290 + mac_size
+ blocksize
;
291 if (s
->d1
->mtu
> used_len
)
292 curr_mtu
= s
->d1
->mtu
- used_len
;
296 if (curr_mtu
<= DTLS1_HM_HEADER_LENGTH
) {
298 * grr.. we could get an error if MTU picked was wrong
300 ret
= BIO_flush(SSL_get_wbio(s
));
303 used_len
= DTLS1_RT_HEADER_LENGTH
+ mac_size
+ blocksize
;
304 if (s
->d1
->mtu
> used_len
+ DTLS1_HM_HEADER_LENGTH
) {
305 curr_mtu
= s
->d1
->mtu
- used_len
;
307 /* Shouldn't happen */
313 * We just checked that s->init_num > 0 so this cast should be safe
315 if (((unsigned int)s
->init_num
) > curr_mtu
)
320 /* Shouldn't ever happen */
325 * XDTLS: this function is too long. split out the CCS part
327 if (type
== SSL3_RT_HANDSHAKE
) {
328 if (s
->init_off
!= 0) {
329 OPENSSL_assert(s
->init_off
> DTLS1_HM_HEADER_LENGTH
);
330 s
->init_off
-= DTLS1_HM_HEADER_LENGTH
;
331 s
->init_num
+= DTLS1_HM_HEADER_LENGTH
;
334 * We just checked that s->init_num > 0 so this cast should
337 if (((unsigned int)s
->init_num
) > curr_mtu
)
343 /* Shouldn't ever happen */
347 if (len
< DTLS1_HM_HEADER_LENGTH
) {
349 * len is so small that we really can't do anything sensible
354 dtls1_fix_message_header(s
, frag_off
,
355 len
- DTLS1_HM_HEADER_LENGTH
);
357 dtls1_write_message_header(s
,
358 (unsigned char *)&s
->init_buf
->
362 ret
= dtls1_write_bytes(s
, type
, &s
->init_buf
->data
[s
->init_off
],
366 * might need to update MTU here, but we don't know which
367 * previous packet caused the failure -- so can't really
368 * retransmit anything. continue as if everything is fine and
369 * wait for an alert to handle the retransmit
371 if (retry
&& BIO_ctrl(SSL_get_wbio(s
),
372 BIO_CTRL_DGRAM_MTU_EXCEEDED
, 0, NULL
) > 0) {
373 if (!(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
374 if (!dtls1_query_mtu(s
))
376 /* Have one more go */
386 * bad if this assert fails, only part of the handshake message
387 * got sent. but why would this happen?
389 OPENSSL_assert(len
== (unsigned int)ret
);
391 if (type
== SSL3_RT_HANDSHAKE
&& !s
->d1
->retransmitting
) {
393 * should not be done for 'Hello Request's, but in that case
394 * we'll ignore the result anyway
397 (unsigned char *)&s
->init_buf
->data
[s
->init_off
];
398 const struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
401 if (frag_off
== 0 && s
->version
!= DTLS1_BAD_VER
) {
403 * reconstruct message header is if it is being sent in
406 *p
++ = msg_hdr
->type
;
407 l2n3(msg_hdr
->msg_len
, p
);
408 s2n(msg_hdr
->seq
, p
);
410 l2n3(msg_hdr
->msg_len
, p
);
411 p
-= DTLS1_HM_HEADER_LENGTH
;
414 p
+= DTLS1_HM_HEADER_LENGTH
;
415 xlen
= ret
- DTLS1_HM_HEADER_LENGTH
;
418 ssl3_finish_mac(s
, p
, xlen
);
421 if (ret
== s
->init_num
) {
423 s
->msg_callback(1, s
->version
, type
, s
->init_buf
->data
,
424 (size_t)(s
->init_off
+ s
->init_num
), s
,
425 s
->msg_callback_arg
);
427 s
->init_off
= 0; /* done writing this message */
434 frag_off
+= (ret
-= DTLS1_HM_HEADER_LENGTH
);
441 * Obtain handshake message of message type 'mt' (any if mt == -1), maximum
442 * acceptable body length 'max'. Read an entire handshake message. Handshake
443 * messages arrive in fragments.
445 long dtls1_get_message(SSL
*s
, int st1
, int stn
, int mt
, long max
, int *ok
)
448 struct hm_header_st
*msg_hdr
;
450 unsigned long msg_len
;
453 * s3->tmp is used to store messages that are unexpected, caused by the
454 * absence of an optional handshake message
456 if (s
->s3
->tmp
.reuse_message
) {
457 s
->s3
->tmp
.reuse_message
= 0;
458 if ((mt
>= 0) && (s
->s3
->tmp
.message_type
!= mt
)) {
459 al
= SSL_AD_UNEXPECTED_MESSAGE
;
460 SSLerr(SSL_F_DTLS1_GET_MESSAGE
, SSL_R_UNEXPECTED_MESSAGE
);
464 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
465 s
->init_num
= (int)s
->s3
->tmp
.message_size
;
469 msg_hdr
= &s
->d1
->r_msg_hdr
;
470 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
473 i
= dtls1_get_message_fragment(s
, st1
, stn
, max
, ok
);
474 if (i
== DTLS1_HM_BAD_FRAGMENT
|| i
== DTLS1_HM_FRAGMENT_RETRY
) {
475 /* bad fragment received */
477 } else if (i
<= 0 && !*ok
) {
481 p
= (unsigned char *)s
->init_buf
->data
;
482 msg_len
= msg_hdr
->msg_len
;
484 /* reconstruct message header */
485 *(p
++) = msg_hdr
->type
;
487 s2n(msg_hdr
->seq
, p
);
490 if (s
->version
!= DTLS1_BAD_VER
) {
491 p
-= DTLS1_HM_HEADER_LENGTH
;
492 msg_len
+= DTLS1_HM_HEADER_LENGTH
;
495 ssl3_finish_mac(s
, p
, msg_len
);
497 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
498 p
, msg_len
, s
, s
->msg_callback_arg
);
500 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
502 /* Don't change sequence numbers while listening */
504 s
->d1
->handshake_read_seq
++;
506 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
510 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
515 static int dtls1_preprocess_fragment(SSL
*s
, struct hm_header_st
*msg_hdr
,
518 size_t frag_off
, frag_len
, msg_len
;
520 msg_len
= msg_hdr
->msg_len
;
521 frag_off
= msg_hdr
->frag_off
;
522 frag_len
= msg_hdr
->frag_len
;
524 /* sanity checking */
525 if ((frag_off
+ frag_len
) > msg_len
) {
526 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
527 return SSL_AD_ILLEGAL_PARAMETER
;
530 if ((frag_off
+ frag_len
) > (unsigned long)max
) {
531 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
532 return SSL_AD_ILLEGAL_PARAMETER
;
535 if (s
->d1
->r_msg_hdr
.frag_off
== 0) { /* first fragment */
537 * msg_len is limited to 2^24, but is effectively checked against max
540 if (!BUF_MEM_grow_clean
541 (s
->init_buf
, msg_len
+ DTLS1_HM_HEADER_LENGTH
)) {
542 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, ERR_R_BUF_LIB
);
543 return SSL_AD_INTERNAL_ERROR
;
546 s
->s3
->tmp
.message_size
= msg_len
;
547 s
->d1
->r_msg_hdr
.msg_len
= msg_len
;
548 s
->s3
->tmp
.message_type
= msg_hdr
->type
;
549 s
->d1
->r_msg_hdr
.type
= msg_hdr
->type
;
550 s
->d1
->r_msg_hdr
.seq
= msg_hdr
->seq
;
551 } else if (msg_len
!= s
->d1
->r_msg_hdr
.msg_len
) {
553 * They must be playing with us! BTW, failure to enforce upper limit
554 * would open possibility for buffer overrun.
556 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
557 return SSL_AD_ILLEGAL_PARAMETER
;
560 return 0; /* no error */
563 static int dtls1_retrieve_buffered_fragment(SSL
*s
, long max
, int *ok
)
566 * (0) check whether the desired fragment is available
568 * (1) copy over the fragment to s->init_buf->data[]
569 * (2) update s->init_num
576 item
= pqueue_peek(s
->d1
->buffered_messages
);
580 frag
= (hm_fragment
*)item
->data
;
582 /* Don't return if reassembly still in progress */
583 if (frag
->reassembly
!= NULL
)
586 if (s
->d1
->handshake_read_seq
== frag
->msg_header
.seq
) {
587 unsigned long frag_len
= frag
->msg_header
.frag_len
;
588 pqueue_pop(s
->d1
->buffered_messages
);
590 al
= dtls1_preprocess_fragment(s
, &frag
->msg_header
, max
);
592 if (al
== 0) { /* no alert */
594 (unsigned char *)s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
595 memcpy(&p
[frag
->msg_header
.frag_off
], frag
->fragment
,
596 frag
->msg_header
.frag_len
);
599 dtls1_hm_fragment_free(frag
);
607 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
616 * dtls1_max_handshake_message_len returns the maximum number of bytes
617 * permitted in a DTLS handshake message for |s|. The minimum is 16KB, but
618 * may be greater if the maximum certificate list size requires it.
620 static unsigned long dtls1_max_handshake_message_len(const SSL
*s
)
622 unsigned long max_len
=
623 DTLS1_HM_HEADER_LENGTH
+ SSL3_RT_MAX_ENCRYPTED_LENGTH
;
624 if (max_len
< (unsigned long)s
->max_cert_list
)
625 return s
->max_cert_list
;
630 dtls1_reassemble_fragment(SSL
*s
, const struct hm_header_st
*msg_hdr
, int *ok
)
632 hm_fragment
*frag
= NULL
;
634 int i
= -1, is_complete
;
635 unsigned char seq64be
[8];
636 unsigned long frag_len
= msg_hdr
->frag_len
;
638 if ((msg_hdr
->frag_off
+ frag_len
) > msg_hdr
->msg_len
||
639 msg_hdr
->msg_len
> dtls1_max_handshake_message_len(s
))
643 return DTLS1_HM_FRAGMENT_RETRY
;
645 /* Try to find item in queue */
646 memset(seq64be
, 0, sizeof(seq64be
));
647 seq64be
[6] = (unsigned char)(msg_hdr
->seq
>> 8);
648 seq64be
[7] = (unsigned char)msg_hdr
->seq
;
649 item
= pqueue_find(s
->d1
->buffered_messages
, seq64be
);
652 frag
= dtls1_hm_fragment_new(msg_hdr
->msg_len
, 1);
655 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
656 frag
->msg_header
.frag_len
= frag
->msg_header
.msg_len
;
657 frag
->msg_header
.frag_off
= 0;
659 frag
= (hm_fragment
*)item
->data
;
660 if (frag
->msg_header
.msg_len
!= msg_hdr
->msg_len
) {
668 * If message is already reassembled, this must be a retransmit and can
669 * be dropped. In this case item != NULL and so frag does not need to be
672 if (frag
->reassembly
== NULL
) {
673 unsigned char devnull
[256];
676 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
679 sizeof(devnull
) ? sizeof(devnull
) :
685 return DTLS1_HM_FRAGMENT_RETRY
;
688 /* read the body of the fragment (header has already been read */
689 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
690 frag
->fragment
+ msg_hdr
->frag_off
,
692 if ((unsigned long)i
!= frag_len
)
697 RSMBLY_BITMASK_MARK(frag
->reassembly
, (long)msg_hdr
->frag_off
,
698 (long)(msg_hdr
->frag_off
+ frag_len
));
700 RSMBLY_BITMASK_IS_COMPLETE(frag
->reassembly
, (long)msg_hdr
->msg_len
,
704 OPENSSL_free(frag
->reassembly
);
705 frag
->reassembly
= NULL
;
709 item
= pitem_new(seq64be
, frag
);
715 item
= pqueue_insert(s
->d1
->buffered_messages
, item
);
717 * pqueue_insert fails iff a duplicate item is inserted. However,
718 * |item| cannot be a duplicate. If it were, |pqueue_find|, above,
719 * would have returned it and control would never have reached this
722 OPENSSL_assert(item
!= NULL
);
725 return DTLS1_HM_FRAGMENT_RETRY
;
729 dtls1_hm_fragment_free(frag
);
735 dtls1_process_out_of_seq_message(SSL
*s
, const struct hm_header_st
*msg_hdr
,
739 hm_fragment
*frag
= NULL
;
741 unsigned char seq64be
[8];
742 unsigned long frag_len
= msg_hdr
->frag_len
;
744 if ((msg_hdr
->frag_off
+ frag_len
) > msg_hdr
->msg_len
)
747 /* Try to find item in queue, to prevent duplicate entries */
748 memset(seq64be
, 0, sizeof(seq64be
));
749 seq64be
[6] = (unsigned char)(msg_hdr
->seq
>> 8);
750 seq64be
[7] = (unsigned char)msg_hdr
->seq
;
751 item
= pqueue_find(s
->d1
->buffered_messages
, seq64be
);
754 * If we already have an entry and this one is a fragment, don't discard
755 * it and rather try to reassemble it.
757 if (item
!= NULL
&& frag_len
!= msg_hdr
->msg_len
)
761 * Discard the message if sequence number was already there, is too far
762 * in the future, already in the queue or if we received a FINISHED
763 * before the SERVER_HELLO, which then must be a stale retransmit.
765 if (msg_hdr
->seq
<= s
->d1
->handshake_read_seq
||
766 msg_hdr
->seq
> s
->d1
->handshake_read_seq
+ 10 || item
!= NULL
||
767 (s
->d1
->handshake_read_seq
== 0 && msg_hdr
->type
== SSL3_MT_FINISHED
))
769 unsigned char devnull
[256];
772 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
775 sizeof(devnull
) ? sizeof(devnull
) :
782 if (frag_len
!= msg_hdr
->msg_len
)
783 return dtls1_reassemble_fragment(s
, msg_hdr
, ok
);
785 if (frag_len
> dtls1_max_handshake_message_len(s
))
788 frag
= dtls1_hm_fragment_new(frag_len
, 0);
792 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
796 * read the body of the fragment (header has already been read
798 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
799 frag
->fragment
, frag_len
, 0);
800 if ((unsigned long)i
!= frag_len
)
806 item
= pitem_new(seq64be
, frag
);
810 item
= pqueue_insert(s
->d1
->buffered_messages
, item
);
812 * pqueue_insert fails iff a duplicate item is inserted. However,
813 * |item| cannot be a duplicate. If it were, |pqueue_find|, above,
814 * would have returned it. Then, either |frag_len| !=
815 * |msg_hdr->msg_len| in which case |item| is set to NULL and it will
816 * have been processed with |dtls1_reassemble_fragment|, above, or
817 * the record will have been discarded.
819 OPENSSL_assert(item
!= NULL
);
822 return DTLS1_HM_FRAGMENT_RETRY
;
826 dtls1_hm_fragment_free(frag
);
832 dtls1_get_message_fragment(SSL
*s
, int st1
, int stn
, long max
, int *ok
)
834 unsigned char wire
[DTLS1_HM_HEADER_LENGTH
];
835 unsigned long len
, frag_off
, frag_len
;
837 struct hm_header_st msg_hdr
;
840 /* see if we have the required fragment already */
841 if ((frag_len
= dtls1_retrieve_buffered_fragment(s
, max
, ok
)) || *ok
) {
843 s
->init_num
= frag_len
;
847 /* read handshake message header */
848 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, wire
,
849 DTLS1_HM_HEADER_LENGTH
, 0);
850 if (i
<= 0) { /* nbio, or an error */
851 s
->rwstate
= SSL_READING
;
855 /* Handshake fails if message header is incomplete */
856 if (i
!= DTLS1_HM_HEADER_LENGTH
) {
857 al
= SSL_AD_UNEXPECTED_MESSAGE
;
858 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
, SSL_R_UNEXPECTED_MESSAGE
);
862 /* parse the message fragment header */
863 dtls1_get_message_header(wire
, &msg_hdr
);
866 * if this is a future (or stale) message it gets buffered
867 * (or dropped)--no further processing at this time
868 * While listening, we accept seq 1 (ClientHello with cookie)
869 * although we're still expecting seq 0 (ClientHello)
871 if (msg_hdr
.seq
!= s
->d1
->handshake_read_seq
872 && !(s
->d1
->listen
&& msg_hdr
.seq
== 1))
873 return dtls1_process_out_of_seq_message(s
, &msg_hdr
, ok
);
875 len
= msg_hdr
.msg_len
;
876 frag_off
= msg_hdr
.frag_off
;
877 frag_len
= msg_hdr
.frag_len
;
879 if (frag_len
&& frag_len
< len
)
880 return dtls1_reassemble_fragment(s
, &msg_hdr
, ok
);
882 if (!s
->server
&& s
->d1
->r_msg_hdr
.frag_off
== 0 &&
883 wire
[0] == SSL3_MT_HELLO_REQUEST
) {
885 * The server may always send 'Hello Request' messages -- we are
886 * doing a handshake anyway now, so ignore them if their format is
887 * correct. Does not count for 'Finished' MAC.
889 if (wire
[1] == 0 && wire
[2] == 0 && wire
[3] == 0) {
891 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
892 wire
, DTLS1_HM_HEADER_LENGTH
, s
,
893 s
->msg_callback_arg
);
897 } else { /* Incorrectly formated Hello request */
899 al
= SSL_AD_UNEXPECTED_MESSAGE
;
900 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
,
901 SSL_R_UNEXPECTED_MESSAGE
);
906 if ((al
= dtls1_preprocess_fragment(s
, &msg_hdr
, max
)))
909 /* XDTLS: ressurect this when restart is in place */
914 (unsigned char *)s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
916 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
,
917 &p
[frag_off
], frag_len
, 0);
919 * XDTLS: fix this--message fragments cannot span multiple packets
922 s
->rwstate
= SSL_READING
;
930 * XDTLS: an incorrectly formatted fragment should cause the handshake
933 if (i
!= (int)frag_len
) {
934 al
= SSL3_AD_ILLEGAL_PARAMETER
;
935 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT
, SSL3_AD_ILLEGAL_PARAMETER
);
942 * Note that s->init_num is *not* used as current offset in
943 * s->init_buf->data, but as a counter summing up fragments' lengths: as
944 * soon as they sum up to handshake packet length, we assume we have got
947 s
->init_num
= frag_len
;
951 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
959 * for these 2 messages, we need to
960 * ssl->enc_read_ctx re-init
961 * ssl->rlayer.read_sequence zero
962 * ssl->s3->read_mac_secret re-init
963 * ssl->session->read_sym_enc assign
964 * ssl->session->read_compression assign
965 * ssl->session->read_hash assign
967 int dtls1_send_change_cipher_spec(SSL
*s
, int a
, int b
)
972 p
= (unsigned char *)s
->init_buf
->data
;
974 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
975 s
->init_num
= DTLS1_CCS_HEADER_LENGTH
;
977 if (s
->version
== DTLS1_BAD_VER
) {
978 s
->d1
->next_handshake_write_seq
++;
979 s2n(s
->d1
->handshake_write_seq
, p
);
985 dtls1_set_message_header_int(s
, SSL3_MT_CCS
, 0,
986 s
->d1
->handshake_write_seq
, 0, 0);
988 /* buffer the message to handle re-xmits */
989 if (!dtls1_buffer_message(s
, 1)) {
990 SSLerr(SSL_F_DTLS1_SEND_CHANGE_CIPHER_SPEC
, ERR_R_INTERNAL_ERROR
);
997 /* SSL3_ST_CW_CHANGE_B */
998 return (dtls1_do_write(s
, SSL3_RT_CHANGE_CIPHER_SPEC
));
1001 int dtls1_read_failed(SSL
*s
, int code
)
1004 fprintf(stderr
, "invalid state reached %s:%d", __FILE__
, __LINE__
);
1008 if (!dtls1_is_timer_expired(s
)) {
1010 * not a timeout, none of our business, let higher layers handle
1011 * this. in fact it's probably an error
1015 #ifndef OPENSSL_NO_HEARTBEATS
1016 /* done, no need to send a retransmit */
1017 if (!SSL_in_init(s
) && !s
->tlsext_hb_pending
)
1019 /* done, no need to send a retransmit */
1020 if (!SSL_in_init(s
))
1023 BIO_set_flags(SSL_get_rbio(s
), BIO_FLAGS_READ
);
1027 return dtls1_handle_timeout(s
);
1030 int dtls1_get_queue_priority(unsigned short seq
, int is_ccs
)
1033 * The index of the retransmission queue actually is the message sequence
1034 * number, since the queue only contains messages of a single handshake.
1035 * However, the ChangeCipherSpec has no message sequence number and so
1036 * using only the sequence will result in the CCS and Finished having the
1037 * same index. To prevent this, the sequence number is multiplied by 2.
1038 * In case of a CCS 1 is subtracted. This does not only differ CSS and
1039 * Finished, it also maintains the order of the index (important for
1040 * priority queues) and fits in the unsigned short variable.
1042 return seq
* 2 - is_ccs
;
1045 int dtls1_retransmit_buffered_messages(SSL
*s
)
1047 pqueue sent
= s
->d1
->sent_messages
;
1053 iter
= pqueue_iterator(sent
);
1055 for (item
= pqueue_next(&iter
); item
!= NULL
; item
= pqueue_next(&iter
)) {
1056 frag
= (hm_fragment
*)item
->data
;
1057 if (dtls1_retransmit_message(s
, (unsigned short)
1058 dtls1_get_queue_priority
1059 (frag
->msg_header
.seq
,
1060 frag
->msg_header
.is_ccs
), 0,
1061 &found
) <= 0 && found
) {
1062 fprintf(stderr
, "dtls1_retransmit_message() failed\n");
1070 int dtls1_buffer_message(SSL
*s
, int is_ccs
)
1074 unsigned char seq64be
[8];
1077 * this function is called immediately after a message has been
1080 OPENSSL_assert(s
->init_off
== 0);
1082 frag
= dtls1_hm_fragment_new(s
->init_num
, 0);
1086 memcpy(frag
->fragment
, s
->init_buf
->data
, s
->init_num
);
1089 /* For DTLS1_BAD_VER the header length is non-standard */
1090 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
1091 ((s
->version
==DTLS1_BAD_VER
)?3:DTLS1_CCS_HEADER_LENGTH
)
1092 == (unsigned int)s
->init_num
);
1094 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
1095 DTLS1_HM_HEADER_LENGTH
== (unsigned int)s
->init_num
);
1098 frag
->msg_header
.msg_len
= s
->d1
->w_msg_hdr
.msg_len
;
1099 frag
->msg_header
.seq
= s
->d1
->w_msg_hdr
.seq
;
1100 frag
->msg_header
.type
= s
->d1
->w_msg_hdr
.type
;
1101 frag
->msg_header
.frag_off
= 0;
1102 frag
->msg_header
.frag_len
= s
->d1
->w_msg_hdr
.msg_len
;
1103 frag
->msg_header
.is_ccs
= is_ccs
;
1105 /* save current state */
1106 frag
->msg_header
.saved_retransmit_state
.enc_write_ctx
= s
->enc_write_ctx
;
1107 frag
->msg_header
.saved_retransmit_state
.write_hash
= s
->write_hash
;
1108 frag
->msg_header
.saved_retransmit_state
.compress
= s
->compress
;
1109 frag
->msg_header
.saved_retransmit_state
.session
= s
->session
;
1110 frag
->msg_header
.saved_retransmit_state
.epoch
=
1111 DTLS_RECORD_LAYER_get_w_epoch(&s
->rlayer
);
1113 memset(seq64be
, 0, sizeof(seq64be
));
1116 char)(dtls1_get_queue_priority(frag
->msg_header
.seq
,
1117 frag
->msg_header
.is_ccs
) >> 8);
1120 char)(dtls1_get_queue_priority(frag
->msg_header
.seq
,
1121 frag
->msg_header
.is_ccs
));
1123 item
= pitem_new(seq64be
, frag
);
1125 dtls1_hm_fragment_free(frag
);
1129 pqueue_insert(s
->d1
->sent_messages
, item
);
1134 dtls1_retransmit_message(SSL
*s
, unsigned short seq
, unsigned long frag_off
,
1138 /* XDTLS: for now assuming that read/writes are blocking */
1141 unsigned long header_length
;
1142 unsigned char seq64be
[8];
1143 struct dtls1_retransmit_state saved_state
;
1146 OPENSSL_assert(s->init_num == 0);
1147 OPENSSL_assert(s->init_off == 0);
1150 /* XDTLS: the requested message ought to be found, otherwise error */
1151 memset(seq64be
, 0, sizeof(seq64be
));
1152 seq64be
[6] = (unsigned char)(seq
>> 8);
1153 seq64be
[7] = (unsigned char)seq
;
1155 item
= pqueue_find(s
->d1
->sent_messages
, seq64be
);
1157 fprintf(stderr
, "retransmit: message %d non-existant\n", seq
);
1163 frag
= (hm_fragment
*)item
->data
;
1165 if (frag
->msg_header
.is_ccs
)
1166 header_length
= DTLS1_CCS_HEADER_LENGTH
;
1168 header_length
= DTLS1_HM_HEADER_LENGTH
;
1170 memcpy(s
->init_buf
->data
, frag
->fragment
,
1171 frag
->msg_header
.msg_len
+ header_length
);
1172 s
->init_num
= frag
->msg_header
.msg_len
+ header_length
;
1174 dtls1_set_message_header_int(s
, frag
->msg_header
.type
,
1175 frag
->msg_header
.msg_len
,
1176 frag
->msg_header
.seq
, 0,
1177 frag
->msg_header
.frag_len
);
1179 /* save current state */
1180 saved_state
.enc_write_ctx
= s
->enc_write_ctx
;
1181 saved_state
.write_hash
= s
->write_hash
;
1182 saved_state
.compress
= s
->compress
;
1183 saved_state
.session
= s
->session
;
1184 saved_state
.epoch
= DTLS_RECORD_LAYER_get_w_epoch(&s
->rlayer
);
1186 s
->d1
->retransmitting
= 1;
1188 /* restore state in which the message was originally sent */
1189 s
->enc_write_ctx
= frag
->msg_header
.saved_retransmit_state
.enc_write_ctx
;
1190 s
->write_hash
= frag
->msg_header
.saved_retransmit_state
.write_hash
;
1191 s
->compress
= frag
->msg_header
.saved_retransmit_state
.compress
;
1192 s
->session
= frag
->msg_header
.saved_retransmit_state
.session
;
1193 DTLS_RECORD_LAYER_set_saved_w_epoch(&s
->rlayer
,
1194 frag
->msg_header
.saved_retransmit_state
.epoch
);
1196 ret
= dtls1_do_write(s
, frag
->msg_header
.is_ccs
?
1197 SSL3_RT_CHANGE_CIPHER_SPEC
: SSL3_RT_HANDSHAKE
);
1199 /* restore current state */
1200 s
->enc_write_ctx
= saved_state
.enc_write_ctx
;
1201 s
->write_hash
= saved_state
.write_hash
;
1202 s
->compress
= saved_state
.compress
;
1203 s
->session
= saved_state
.session
;
1204 DTLS_RECORD_LAYER_set_saved_w_epoch(&s
->rlayer
, saved_state
.epoch
);
1206 s
->d1
->retransmitting
= 0;
1208 (void)BIO_flush(SSL_get_wbio(s
));
1212 /* call this function when the buffered messages are no longer needed */
1213 void dtls1_clear_record_buffer(SSL
*s
)
1217 for (item
= pqueue_pop(s
->d1
->sent_messages
);
1218 item
!= NULL
; item
= pqueue_pop(s
->d1
->sent_messages
)) {
1219 dtls1_hm_fragment_free((hm_fragment
*)item
->data
);
1224 void dtls1_set_message_header(SSL
*s
, unsigned char *p
,
1225 unsigned char mt
, unsigned long len
,
1226 unsigned long frag_off
,
1227 unsigned long frag_len
)
1229 /* Don't change sequence numbers while listening */
1230 if (frag_off
== 0 && !s
->d1
->listen
) {
1231 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
1232 s
->d1
->next_handshake_write_seq
++;
1235 dtls1_set_message_header_int(s
, mt
, len
, s
->d1
->handshake_write_seq
,
1236 frag_off
, frag_len
);
1239 /* don't actually do the writing, wait till the MTU has been retrieved */
1241 dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
1242 unsigned long len
, unsigned short seq_num
,
1243 unsigned long frag_off
, unsigned long frag_len
)
1245 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1248 msg_hdr
->msg_len
= len
;
1249 msg_hdr
->seq
= seq_num
;
1250 msg_hdr
->frag_off
= frag_off
;
1251 msg_hdr
->frag_len
= frag_len
;
1255 dtls1_fix_message_header(SSL
*s
, unsigned long frag_off
,
1256 unsigned long frag_len
)
1258 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1260 msg_hdr
->frag_off
= frag_off
;
1261 msg_hdr
->frag_len
= frag_len
;
1264 static unsigned char *dtls1_write_message_header(SSL
*s
, unsigned char *p
)
1266 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1268 *p
++ = msg_hdr
->type
;
1269 l2n3(msg_hdr
->msg_len
, p
);
1271 s2n(msg_hdr
->seq
, p
);
1272 l2n3(msg_hdr
->frag_off
, p
);
1273 l2n3(msg_hdr
->frag_len
, p
);
1278 unsigned int dtls1_link_min_mtu(void)
1280 return (g_probable_mtu
[(sizeof(g_probable_mtu
) /
1281 sizeof(g_probable_mtu
[0])) - 1]);
1284 unsigned int dtls1_min_mtu(SSL
*s
)
1286 return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s
));
1290 dtls1_get_message_header(unsigned char *data
, struct hm_header_st
*msg_hdr
)
1292 memset(msg_hdr
, 0x00, sizeof(struct hm_header_st
));
1293 msg_hdr
->type
= *(data
++);
1294 n2l3(data
, msg_hdr
->msg_len
);
1296 n2s(data
, msg_hdr
->seq
);
1297 n2l3(data
, msg_hdr
->frag_off
);
1298 n2l3(data
, msg_hdr
->frag_len
);
1301 void dtls1_get_ccs_header(unsigned char *data
, struct ccs_header_st
*ccs_hdr
)
1303 memset(ccs_hdr
, 0x00, sizeof(struct ccs_header_st
));
1305 ccs_hdr
->type
= *(data
++);
1308 int dtls1_shutdown(SSL
*s
)
1311 #ifndef OPENSSL_NO_SCTP
1312 if (BIO_dgram_is_sctp(SSL_get_wbio(s
)) &&
1313 !(s
->shutdown
& SSL_SENT_SHUTDOWN
)) {
1314 ret
= BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s
));
1319 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN
, 1,
1323 ret
= ssl3_shutdown(s
);
1324 #ifndef OPENSSL_NO_SCTP
1325 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN
, 0, NULL
);
1330 #ifndef OPENSSL_NO_HEARTBEATS
1331 int dtls1_process_heartbeat(SSL
*s
, unsigned char *p
, unsigned int length
)
1334 unsigned short hbtype
;
1335 unsigned int payload
;
1336 unsigned int padding
= 16; /* Use minimum padding */
1338 if (s
->msg_callback
)
1339 s
->msg_callback(0, s
->version
, TLS1_RT_HEARTBEAT
,
1340 p
, length
, s
, s
->msg_callback_arg
);
1342 /* Read type and payload length first */
1343 if (1 + 2 + 16 > length
)
1344 return 0; /* silently discard */
1345 if (length
> SSL3_RT_MAX_PLAIN_LENGTH
)
1346 return 0; /* silently discard per RFC 6520 sec. 4 */
1350 if (1 + 2 + payload
+ 16 > length
)
1351 return 0; /* silently discard per RFC 6520 sec. 4 */
1354 if (hbtype
== TLS1_HB_REQUEST
) {
1355 unsigned char *buffer
, *bp
;
1356 unsigned int write_length
= 1 /* heartbeat type */ +
1357 2 /* heartbeat length */ +
1361 if (write_length
> SSL3_RT_MAX_PLAIN_LENGTH
)
1365 * Allocate memory for the response, size is 1 byte message type,
1366 * plus 2 bytes payload length, plus payload, plus padding
1368 buffer
= OPENSSL_malloc(write_length
);
1373 /* Enter response type, length and copy payload */
1374 *bp
++ = TLS1_HB_RESPONSE
;
1376 memcpy(bp
, pl
, payload
);
1378 /* Random padding */
1379 if (RAND_bytes(bp
, padding
) <= 0) {
1380 OPENSSL_free(buffer
);
1384 r
= dtls1_write_bytes(s
, TLS1_RT_HEARTBEAT
, buffer
, write_length
);
1386 if (r
>= 0 && s
->msg_callback
)
1387 s
->msg_callback(1, s
->version
, TLS1_RT_HEARTBEAT
,
1388 buffer
, write_length
, s
, s
->msg_callback_arg
);
1390 OPENSSL_free(buffer
);
1394 } else if (hbtype
== TLS1_HB_RESPONSE
) {
1398 * We only send sequence numbers (2 bytes unsigned int), and 16
1399 * random bytes, so we just try to read the sequence number
1403 if (payload
== 18 && seq
== s
->tlsext_hb_seq
) {
1404 dtls1_stop_timer(s
);
1406 s
->tlsext_hb_pending
= 0;
1413 int dtls1_heartbeat(SSL
*s
)
1415 unsigned char *buf
, *p
;
1417 unsigned int payload
= 18; /* Sequence number + random bytes */
1418 unsigned int padding
= 16; /* Use minimum padding */
1420 /* Only send if peer supports and accepts HB requests... */
1421 if (!(s
->tlsext_heartbeat
& SSL_TLSEXT_HB_ENABLED
) ||
1422 s
->tlsext_heartbeat
& SSL_TLSEXT_HB_DONT_SEND_REQUESTS
) {
1423 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT
);
1427 /* ...and there is none in flight yet... */
1428 if (s
->tlsext_hb_pending
) {
1429 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_TLS_HEARTBEAT_PENDING
);
1433 /* ...and no handshake in progress. */
1434 if (SSL_in_init(s
) || s
->in_handshake
) {
1435 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_UNEXPECTED_MESSAGE
);
1440 * Check if padding is too long, payload and padding must not exceed 2^14
1441 * - 3 = 16381 bytes in total.
1443 OPENSSL_assert(payload
+ padding
<= 16381);
1446 * Create HeartBeat message, we just use a sequence number
1447 * as payload to distuingish different messages and add
1448 * some random stuff.
1449 * - Message Type, 1 byte
1450 * - Payload Length, 2 bytes (unsigned int)
1451 * - Payload, the sequence number (2 bytes uint)
1452 * - Payload, random bytes (16 bytes uint)
1455 buf
= OPENSSL_malloc(1 + 2 + payload
+ padding
);
1457 SSLerr(SSL_F_DTLS1_HEARTBEAT
, ERR_R_MALLOC_FAILURE
);
1462 *p
++ = TLS1_HB_REQUEST
;
1463 /* Payload length (18 bytes here) */
1465 /* Sequence number */
1466 s2n(s
->tlsext_hb_seq
, p
);
1467 /* 16 random bytes */
1468 if (RAND_bytes(p
, 16) <= 0) {
1469 SSLerr(SSL_F_DTLS1_HEARTBEAT
, ERR_R_INTERNAL_ERROR
);
1473 /* Random padding */
1474 if (RAND_bytes(p
, padding
) <= 0) {
1475 SSLerr(SSL_F_DTLS1_HEARTBEAT
, ERR_R_INTERNAL_ERROR
);
1479 ret
= dtls1_write_bytes(s
, TLS1_RT_HEARTBEAT
, buf
, 3 + payload
+ padding
);
1481 if (s
->msg_callback
)
1482 s
->msg_callback(1, s
->version
, TLS1_RT_HEARTBEAT
,
1483 buf
, 3 + payload
+ padding
,
1484 s
, s
->msg_callback_arg
);
1486 dtls1_start_timer(s
);
1487 s
->tlsext_hb_pending
= 1;