2 * Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
13 #include "../ssl_locl.h"
14 #include "statem_locl.h"
15 #include <openssl/buffer.h>
16 #include <openssl/objects.h>
17 #include <openssl/evp.h>
18 #include <openssl/x509.h>
20 #define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8)
22 #define RSMBLY_BITMASK_MARK(bitmask, start, end) { \
23 if ((end) - (start) <= 8) { \
25 for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \
28 bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \
29 for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \
30 bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \
33 #define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \
35 OPENSSL_assert((msg_len) > 0); \
37 if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \
38 if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \
39 if (bitmask[ii] != 0xff) { is_complete = 0; break; } }
41 static unsigned char bitmask_start_values
[] =
42 { 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 };
43 static unsigned char bitmask_end_values
[] =
44 { 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f };
46 static void dtls1_fix_message_header(SSL
*s
, size_t frag_off
,
48 static unsigned char *dtls1_write_message_header(SSL
*s
, unsigned char *p
);
49 static void dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
51 unsigned short seq_num
,
54 static int dtls_get_reassembled_message(SSL
*s
, int *errtype
, size_t *len
);
56 static hm_fragment
*dtls1_hm_fragment_new(size_t frag_len
, int reassembly
)
58 hm_fragment
*frag
= NULL
;
59 unsigned char *buf
= NULL
;
60 unsigned char *bitmask
= NULL
;
62 frag
= OPENSSL_malloc(sizeof(*frag
));
67 buf
= OPENSSL_malloc(frag_len
);
74 /* zero length fragment gets zero frag->fragment */
77 /* Initialize reassembly bitmask if necessary */
79 bitmask
= OPENSSL_zalloc(RSMBLY_BITMASK_SIZE(frag_len
));
80 if (bitmask
== NULL
) {
87 frag
->reassembly
= bitmask
;
92 void dtls1_hm_fragment_free(hm_fragment
*frag
)
96 if (frag
->msg_header
.is_ccs
) {
97 EVP_CIPHER_CTX_free(frag
->msg_header
.
98 saved_retransmit_state
.enc_write_ctx
);
99 EVP_MD_CTX_free(frag
->msg_header
.saved_retransmit_state
.write_hash
);
101 OPENSSL_free(frag
->fragment
);
102 OPENSSL_free(frag
->reassembly
);
107 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or
108 * SSL3_RT_CHANGE_CIPHER_SPEC)
110 int dtls1_do_write(SSL
*s
, int type
)
116 size_t len
, frag_off
, mac_size
, blocksize
, used_len
;
118 if (!dtls1_query_mtu(s
))
121 if (s
->d1
->mtu
< dtls1_min_mtu(s
))
122 /* should have something reasonable now */
125 if (s
->init_off
== 0 && type
== SSL3_RT_HANDSHAKE
)
126 OPENSSL_assert(s
->init_num
==
127 s
->d1
->w_msg_hdr
.msg_len
+ DTLS1_HM_HEADER_LENGTH
);
131 && (EVP_CIPHER_flags(EVP_CIPHER_CTX_cipher(s
->enc_write_ctx
)) &
132 EVP_CIPH_FLAG_AEAD_CIPHER
) != 0)
135 mac_size
= EVP_MD_CTX_size(s
->write_hash
);
139 if (s
->enc_write_ctx
&&
140 (EVP_CIPHER_CTX_mode(s
->enc_write_ctx
) == EVP_CIPH_CBC_MODE
))
141 blocksize
= 2 * EVP_CIPHER_CTX_block_size(s
->enc_write_ctx
);
146 s
->rwstate
= SSL_NOTHING
;
148 /* s->init_num shouldn't ever be < 0...but just in case */
149 while (s
->init_num
> 0) {
150 if (type
== SSL3_RT_HANDSHAKE
&& s
->init_off
!= 0) {
151 /* We must be writing a fragment other than the first one */
154 /* This is the first attempt at writing out this fragment */
156 if (s
->init_off
<= DTLS1_HM_HEADER_LENGTH
) {
158 * Each fragment that was already sent must at least have
159 * contained the message header plus one other byte.
160 * Therefore |init_off| must have progressed by at least
161 * |DTLS1_HM_HEADER_LENGTH + 1| bytes. If not something went
168 * Adjust |init_off| and |init_num| to allow room for a new
169 * message header for this fragment.
171 s
->init_off
-= DTLS1_HM_HEADER_LENGTH
;
172 s
->init_num
+= DTLS1_HM_HEADER_LENGTH
;
175 * We must have been called again after a retry so use the
176 * fragment offset from our last attempt. We do not need
177 * to adjust |init_off| and |init_num| as above, because
178 * that should already have been done before the retry.
180 frag_off
= s
->d1
->w_msg_hdr
.frag_off
;
184 used_len
= BIO_wpending(s
->wbio
) + DTLS1_RT_HEADER_LENGTH
185 + mac_size
+ blocksize
;
186 if (s
->d1
->mtu
> used_len
)
187 curr_mtu
= s
->d1
->mtu
- used_len
;
191 if (curr_mtu
<= DTLS1_HM_HEADER_LENGTH
) {
193 * grr.. we could get an error if MTU picked was wrong
195 ret
= BIO_flush(s
->wbio
);
197 s
->rwstate
= SSL_WRITING
;
200 used_len
= DTLS1_RT_HEADER_LENGTH
+ mac_size
+ blocksize
;
201 if (s
->d1
->mtu
> used_len
+ DTLS1_HM_HEADER_LENGTH
) {
202 curr_mtu
= s
->d1
->mtu
- used_len
;
204 /* Shouldn't happen */
210 * We just checked that s->init_num > 0 so this cast should be safe
212 if (((unsigned int)s
->init_num
) > curr_mtu
)
218 * XDTLS: this function is too long. split out the CCS part
220 if (type
== SSL3_RT_HANDSHAKE
) {
221 if (len
< DTLS1_HM_HEADER_LENGTH
) {
223 * len is so small that we really can't do anything sensible
228 dtls1_fix_message_header(s
, frag_off
, len
- DTLS1_HM_HEADER_LENGTH
);
230 dtls1_write_message_header(s
,
231 (unsigned char *)&s
->init_buf
->
235 ret
= dtls1_write_bytes(s
, type
, &s
->init_buf
->data
[s
->init_off
], len
,
239 * might need to update MTU here, but we don't know which
240 * previous packet caused the failure -- so can't really
241 * retransmit anything. continue as if everything is fine and
242 * wait for an alert to handle the retransmit
244 if (retry
&& BIO_ctrl(SSL_get_wbio(s
),
245 BIO_CTRL_DGRAM_MTU_EXCEEDED
, 0, NULL
) > 0) {
246 if (!(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
247 if (!dtls1_query_mtu(s
))
249 /* Have one more go */
259 * bad if this assert fails, only part of the handshake message
260 * got sent. but why would this happen?
262 OPENSSL_assert(len
== written
);
264 if (type
== SSL3_RT_HANDSHAKE
&& !s
->d1
->retransmitting
) {
266 * should not be done for 'Hello Request's, but in that case
267 * we'll ignore the result anyway
270 (unsigned char *)&s
->init_buf
->data
[s
->init_off
];
271 const struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
274 if (frag_off
== 0 && s
->version
!= DTLS1_BAD_VER
) {
276 * reconstruct message header is if it is being sent in
279 *p
++ = msg_hdr
->type
;
280 l2n3(msg_hdr
->msg_len
, p
);
281 s2n(msg_hdr
->seq
, p
);
283 l2n3(msg_hdr
->msg_len
, p
);
284 p
-= DTLS1_HM_HEADER_LENGTH
;
287 p
+= DTLS1_HM_HEADER_LENGTH
;
288 xlen
= written
- DTLS1_HM_HEADER_LENGTH
;
291 if (!ssl3_finish_mac(s
, p
, xlen
))
295 if (written
== s
->init_num
) {
297 s
->msg_callback(1, s
->version
, type
, s
->init_buf
->data
,
298 (size_t)(s
->init_off
+ s
->init_num
), s
,
299 s
->msg_callback_arg
);
301 s
->init_off
= 0; /* done writing this message */
306 s
->init_off
+= written
;
307 s
->init_num
-= written
;
308 written
-= DTLS1_HM_HEADER_LENGTH
;
312 * We save the fragment offset for the next fragment so we have it
313 * available in case of an IO retry. We don't know the length of the
314 * next fragment yet so just set that to 0 for now. It will be
315 * updated again later.
317 dtls1_fix_message_header(s
, frag_off
, 0);
323 int dtls_get_message(SSL
*s
, int *mt
, size_t *len
)
325 struct hm_header_st
*msg_hdr
;
331 msg_hdr
= &s
->d1
->r_msg_hdr
;
332 memset(msg_hdr
, 0, sizeof(*msg_hdr
));
335 if (!dtls_get_reassembled_message(s
, &errtype
, &tmplen
)) {
336 if (errtype
== DTLS1_HM_BAD_FRAGMENT
337 || errtype
== DTLS1_HM_FRAGMENT_RETRY
) {
338 /* bad fragment received */
344 *mt
= s
->s3
->tmp
.message_type
;
346 p
= (unsigned char *)s
->init_buf
->data
;
349 if (*mt
== SSL3_MT_CHANGE_CIPHER_SPEC
) {
350 if (s
->msg_callback
) {
351 s
->msg_callback(0, s
->version
, SSL3_RT_CHANGE_CIPHER_SPEC
,
352 p
, 1, s
, s
->msg_callback_arg
);
355 * This isn't a real handshake message so skip the processing below.
360 msg_len
= msg_hdr
->msg_len
;
362 /* reconstruct message header */
363 *(p
++) = msg_hdr
->type
;
365 s2n(msg_hdr
->seq
, p
);
368 if (s
->version
!= DTLS1_BAD_VER
) {
369 p
-= DTLS1_HM_HEADER_LENGTH
;
370 msg_len
+= DTLS1_HM_HEADER_LENGTH
;
373 if (!ssl3_finish_mac(s
, p
, msg_len
))
376 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
377 p
, msg_len
, s
, s
->msg_callback_arg
);
379 memset(msg_hdr
, 0, sizeof(*msg_hdr
));
381 s
->d1
->handshake_read_seq
++;
383 s
->init_msg
= s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
389 * dtls1_max_handshake_message_len returns the maximum number of bytes
390 * permitted in a DTLS handshake message for |s|. The minimum is 16KB, but
391 * may be greater if the maximum certificate list size requires it.
393 static size_t dtls1_max_handshake_message_len(const SSL
*s
)
395 size_t max_len
= DTLS1_HM_HEADER_LENGTH
+ SSL3_RT_MAX_ENCRYPTED_LENGTH
;
396 if (max_len
< s
->max_cert_list
)
397 return s
->max_cert_list
;
401 static int dtls1_preprocess_fragment(SSL
*s
, struct hm_header_st
*msg_hdr
)
403 size_t frag_off
, frag_len
, msg_len
;
405 msg_len
= msg_hdr
->msg_len
;
406 frag_off
= msg_hdr
->frag_off
;
407 frag_len
= msg_hdr
->frag_len
;
409 /* sanity checking */
410 if ((frag_off
+ frag_len
) > msg_len
411 || msg_len
> dtls1_max_handshake_message_len(s
)) {
412 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
413 return SSL_AD_ILLEGAL_PARAMETER
;
416 if (s
->d1
->r_msg_hdr
.frag_off
== 0) { /* first fragment */
418 * msg_len is limited to 2^24, but is effectively checked against
419 * dtls_max_handshake_message_len(s) above
421 if (!BUF_MEM_grow_clean(s
->init_buf
, msg_len
+ DTLS1_HM_HEADER_LENGTH
)) {
422 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, ERR_R_BUF_LIB
);
423 return SSL_AD_INTERNAL_ERROR
;
426 s
->s3
->tmp
.message_size
= msg_len
;
427 s
->d1
->r_msg_hdr
.msg_len
= msg_len
;
428 s
->s3
->tmp
.message_type
= msg_hdr
->type
;
429 s
->d1
->r_msg_hdr
.type
= msg_hdr
->type
;
430 s
->d1
->r_msg_hdr
.seq
= msg_hdr
->seq
;
431 } else if (msg_len
!= s
->d1
->r_msg_hdr
.msg_len
) {
433 * They must be playing with us! BTW, failure to enforce upper limit
434 * would open possibility for buffer overrun.
436 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT
, SSL_R_EXCESSIVE_MESSAGE_SIZE
);
437 return SSL_AD_ILLEGAL_PARAMETER
;
440 return 0; /* no error */
443 static int dtls1_retrieve_buffered_fragment(SSL
*s
, size_t *len
)
446 * (0) check whether the desired fragment is available
448 * (1) copy over the fragment to s->init_buf->data[]
449 * (2) update s->init_num
456 item
= pqueue_peek(s
->d1
->buffered_messages
);
460 frag
= (hm_fragment
*)item
->data
;
462 if (frag
->msg_header
.seq
< s
->d1
->handshake_read_seq
) {
463 /* This is a stale message that has been buffered so clear it */
464 pqueue_pop(s
->d1
->buffered_messages
);
465 dtls1_hm_fragment_free(frag
);
470 } while (item
== NULL
);
472 /* Don't return if reassembly still in progress */
473 if (frag
->reassembly
!= NULL
)
476 if (s
->d1
->handshake_read_seq
== frag
->msg_header
.seq
) {
477 size_t frag_len
= frag
->msg_header
.frag_len
;
478 pqueue_pop(s
->d1
->buffered_messages
);
480 al
= dtls1_preprocess_fragment(s
, &frag
->msg_header
);
482 if (al
== 0) { /* no alert */
484 (unsigned char *)s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
485 memcpy(&p
[frag
->msg_header
.frag_off
], frag
->fragment
,
486 frag
->msg_header
.frag_len
);
489 dtls1_hm_fragment_free(frag
);
497 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
506 dtls1_reassemble_fragment(SSL
*s
, const struct hm_header_st
*msg_hdr
)
508 hm_fragment
*frag
= NULL
;
510 int i
= -1, is_complete
;
511 unsigned char seq64be
[8];
512 size_t frag_len
= msg_hdr
->frag_len
;
515 if ((msg_hdr
->frag_off
+ frag_len
) > msg_hdr
->msg_len
||
516 msg_hdr
->msg_len
> dtls1_max_handshake_message_len(s
))
520 return DTLS1_HM_FRAGMENT_RETRY
;
523 /* Try to find item in queue */
524 memset(seq64be
, 0, sizeof(seq64be
));
525 seq64be
[6] = (unsigned char)(msg_hdr
->seq
>> 8);
526 seq64be
[7] = (unsigned char)msg_hdr
->seq
;
527 item
= pqueue_find(s
->d1
->buffered_messages
, seq64be
);
530 frag
= dtls1_hm_fragment_new(msg_hdr
->msg_len
, 1);
533 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
534 frag
->msg_header
.frag_len
= frag
->msg_header
.msg_len
;
535 frag
->msg_header
.frag_off
= 0;
537 frag
= (hm_fragment
*)item
->data
;
538 if (frag
->msg_header
.msg_len
!= msg_hdr
->msg_len
) {
546 * If message is already reassembled, this must be a retransmit and can
547 * be dropped. In this case item != NULL and so frag does not need to be
550 if (frag
->reassembly
== NULL
) {
551 unsigned char devnull
[256];
554 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, NULL
,
557 sizeof(devnull
) ? sizeof(devnull
) :
558 frag_len
, 0, &readbytes
);
561 frag_len
-= readbytes
;
563 return DTLS1_HM_FRAGMENT_RETRY
;
566 /* read the body of the fragment (header has already been read */
567 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, NULL
,
568 frag
->fragment
+ msg_hdr
->frag_off
,
569 frag_len
, 0, &readbytes
);
570 if (i
<= 0 || readbytes
!= frag_len
)
575 RSMBLY_BITMASK_MARK(frag
->reassembly
, (long)msg_hdr
->frag_off
,
576 (long)(msg_hdr
->frag_off
+ frag_len
));
578 RSMBLY_BITMASK_IS_COMPLETE(frag
->reassembly
, (long)msg_hdr
->msg_len
,
582 OPENSSL_free(frag
->reassembly
);
583 frag
->reassembly
= NULL
;
587 item
= pitem_new(seq64be
, frag
);
593 item
= pqueue_insert(s
->d1
->buffered_messages
, item
);
595 * pqueue_insert fails iff a duplicate item is inserted. However,
596 * |item| cannot be a duplicate. If it were, |pqueue_find|, above,
597 * would have returned it and control would never have reached this
600 OPENSSL_assert(item
!= NULL
);
603 return DTLS1_HM_FRAGMENT_RETRY
;
607 dtls1_hm_fragment_free(frag
);
612 dtls1_process_out_of_seq_message(SSL
*s
, const struct hm_header_st
*msg_hdr
)
615 hm_fragment
*frag
= NULL
;
617 unsigned char seq64be
[8];
618 size_t frag_len
= msg_hdr
->frag_len
;
621 if ((msg_hdr
->frag_off
+ frag_len
) > msg_hdr
->msg_len
)
624 /* Try to find item in queue, to prevent duplicate entries */
625 memset(seq64be
, 0, sizeof(seq64be
));
626 seq64be
[6] = (unsigned char)(msg_hdr
->seq
>> 8);
627 seq64be
[7] = (unsigned char)msg_hdr
->seq
;
628 item
= pqueue_find(s
->d1
->buffered_messages
, seq64be
);
631 * If we already have an entry and this one is a fragment, don't discard
632 * it and rather try to reassemble it.
634 if (item
!= NULL
&& frag_len
!= msg_hdr
->msg_len
)
638 * Discard the message if sequence number was already there, is too far
639 * in the future, already in the queue or if we received a FINISHED
640 * before the SERVER_HELLO, which then must be a stale retransmit.
642 if (msg_hdr
->seq
<= s
->d1
->handshake_read_seq
||
643 msg_hdr
->seq
> s
->d1
->handshake_read_seq
+ 10 || item
!= NULL
||
644 (s
->d1
->handshake_read_seq
== 0 && msg_hdr
->type
== SSL3_MT_FINISHED
)) {
645 unsigned char devnull
[256];
648 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, NULL
,
651 sizeof(devnull
) ? sizeof(devnull
) :
652 frag_len
, 0, &readbytes
);
655 frag_len
-= readbytes
;
658 if (frag_len
!= msg_hdr
->msg_len
) {
659 return dtls1_reassemble_fragment(s
, msg_hdr
);;
662 if (frag_len
> dtls1_max_handshake_message_len(s
))
665 frag
= dtls1_hm_fragment_new(frag_len
, 0);
669 memcpy(&(frag
->msg_header
), msg_hdr
, sizeof(*msg_hdr
));
673 * read the body of the fragment (header has already been read
675 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, NULL
,
676 frag
->fragment
, frag_len
, 0,
678 if (i
<=0 || readbytes
!= frag_len
)
684 item
= pitem_new(seq64be
, frag
);
688 item
= pqueue_insert(s
->d1
->buffered_messages
, item
);
690 * pqueue_insert fails iff a duplicate item is inserted. However,
691 * |item| cannot be a duplicate. If it were, |pqueue_find|, above,
692 * would have returned it. Then, either |frag_len| !=
693 * |msg_hdr->msg_len| in which case |item| is set to NULL and it will
694 * have been processed with |dtls1_reassemble_fragment|, above, or
695 * the record will have been discarded.
697 OPENSSL_assert(item
!= NULL
);
700 return DTLS1_HM_FRAGMENT_RETRY
;
704 dtls1_hm_fragment_free(frag
);
708 static int dtls_get_reassembled_message(SSL
*s
, int *errtype
, size_t *len
)
710 unsigned char wire
[DTLS1_HM_HEADER_LENGTH
];
711 size_t mlen
, frag_off
, frag_len
;
712 int i
, al
, recvd_type
;
713 struct hm_header_st msg_hdr
;
719 /* see if we have the required fragment already */
720 if (dtls1_retrieve_buffered_fragment(s
, &frag_len
)) {
721 s
->init_num
= frag_len
;
726 /* read handshake message header */
727 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, &recvd_type
, wire
,
728 DTLS1_HM_HEADER_LENGTH
, 0, &readbytes
);
729 if (i
<= 0) { /* nbio, or an error */
730 s
->rwstate
= SSL_READING
;
734 if (recvd_type
== SSL3_RT_CHANGE_CIPHER_SPEC
) {
735 if (wire
[0] != SSL3_MT_CCS
) {
736 al
= SSL_AD_UNEXPECTED_MESSAGE
;
737 SSLerr(SSL_F_DTLS_GET_REASSEMBLED_MESSAGE
,
738 SSL_R_BAD_CHANGE_CIPHER_SPEC
);
742 memcpy(s
->init_buf
->data
, wire
, readbytes
);
743 s
->init_num
= readbytes
- 1;
744 s
->init_msg
= s
->init_buf
->data
+ 1;
745 s
->s3
->tmp
.message_type
= SSL3_MT_CHANGE_CIPHER_SPEC
;
746 s
->s3
->tmp
.message_size
= readbytes
- 1;
747 *len
= readbytes
- 1;
751 /* Handshake fails if message header is incomplete */
752 if (readbytes
!= DTLS1_HM_HEADER_LENGTH
) {
753 al
= SSL_AD_UNEXPECTED_MESSAGE
;
754 SSLerr(SSL_F_DTLS_GET_REASSEMBLED_MESSAGE
, SSL_R_UNEXPECTED_MESSAGE
);
758 /* parse the message fragment header */
759 dtls1_get_message_header(wire
, &msg_hdr
);
761 mlen
= msg_hdr
.msg_len
;
762 frag_off
= msg_hdr
.frag_off
;
763 frag_len
= msg_hdr
.frag_len
;
766 * We must have at least frag_len bytes left in the record to be read.
767 * Fragments must not span records.
769 if (frag_len
> RECORD_LAYER_get_rrec_length(&s
->rlayer
)) {
770 al
= SSL3_AD_ILLEGAL_PARAMETER
;
771 SSLerr(SSL_F_DTLS_GET_REASSEMBLED_MESSAGE
, SSL_R_BAD_LENGTH
);
776 * if this is a future (or stale) message it gets buffered
777 * (or dropped)--no further processing at this time
778 * While listening, we accept seq 1 (ClientHello with cookie)
779 * although we're still expecting seq 0 (ClientHello)
781 if (msg_hdr
.seq
!= s
->d1
->handshake_read_seq
) {
782 *errtype
= dtls1_process_out_of_seq_message(s
, &msg_hdr
);
786 if (frag_len
&& frag_len
< mlen
) {
787 *errtype
= dtls1_reassemble_fragment(s
, &msg_hdr
);
791 if (!s
->server
&& s
->d1
->r_msg_hdr
.frag_off
== 0 &&
792 wire
[0] == SSL3_MT_HELLO_REQUEST
) {
794 * The server may always send 'Hello Request' messages -- we are
795 * doing a handshake anyway now, so ignore them if their format is
796 * correct. Does not count for 'Finished' MAC.
798 if (wire
[1] == 0 && wire
[2] == 0 && wire
[3] == 0) {
800 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
,
801 wire
, DTLS1_HM_HEADER_LENGTH
, s
,
802 s
->msg_callback_arg
);
806 } else { /* Incorrectly formatted Hello request */
808 al
= SSL_AD_UNEXPECTED_MESSAGE
;
809 SSLerr(SSL_F_DTLS_GET_REASSEMBLED_MESSAGE
,
810 SSL_R_UNEXPECTED_MESSAGE
);
815 if ((al
= dtls1_preprocess_fragment(s
, &msg_hdr
)))
820 (unsigned char *)s
->init_buf
->data
+ DTLS1_HM_HEADER_LENGTH
;
822 i
= s
->method
->ssl_read_bytes(s
, SSL3_RT_HANDSHAKE
, NULL
,
823 &p
[frag_off
], frag_len
, 0, &readbytes
);
826 * This shouldn't ever fail due to NBIO because we already checked
827 * that we have enough data in the record
830 s
->rwstate
= SSL_READING
;
839 * XDTLS: an incorrectly formatted fragment should cause the handshake
842 if (readbytes
!= frag_len
) {
843 al
= SSL3_AD_ILLEGAL_PARAMETER
;
844 SSLerr(SSL_F_DTLS_GET_REASSEMBLED_MESSAGE
, SSL3_AD_ILLEGAL_PARAMETER
);
849 * Note that s->init_num is *not* used as current offset in
850 * s->init_buf->data, but as a counter summing up fragments' lengths: as
851 * soon as they sum up to handshake packet length, we assume we have got
854 *len
= s
->init_num
= frag_len
;
858 ssl3_send_alert(s
, SSL3_AL_FATAL
, al
);
865 * for these 2 messages, we need to
866 * ssl->enc_read_ctx re-init
867 * ssl->rlayer.read_sequence zero
868 * ssl->s3->read_mac_secret re-init
869 * ssl->session->read_sym_enc assign
870 * ssl->session->read_compression assign
871 * ssl->session->read_hash assign
873 int dtls_construct_change_cipher_spec(SSL
*s
, WPACKET
*pkt
)
875 if (s
->version
== DTLS1_BAD_VER
) {
876 s
->d1
->next_handshake_write_seq
++;
878 if (!WPACKET_put_bytes_u16(pkt
, s
->d1
->handshake_write_seq
)) {
879 SSLerr(SSL_F_DTLS_CONSTRUCT_CHANGE_CIPHER_SPEC
, ERR_R_INTERNAL_ERROR
);
880 ssl3_send_alert(s
, SSL3_AL_FATAL
, SSL_AD_INTERNAL_ERROR
);
887 #ifndef OPENSSL_NO_SCTP
888 WORK_STATE
dtls_wait_for_dry(SSL
*s
)
892 /* read app data until dry event */
893 ret
= BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s
));
898 s
->s3
->in_read_app_data
= 2;
899 s
->rwstate
= SSL_READING
;
900 BIO_clear_retry_flags(SSL_get_rbio(s
));
901 BIO_set_retry_read(SSL_get_rbio(s
));
904 return WORK_FINISHED_CONTINUE
;
908 int dtls1_read_failed(SSL
*s
, int code
)
911 SSLerr(SSL_F_DTLS1_READ_FAILED
, ERR_R_INTERNAL_ERROR
);
915 if (!dtls1_is_timer_expired(s
)) {
917 * not a timeout, none of our business, let higher layers handle
918 * this. in fact it's probably an error
922 /* done, no need to send a retransmit */
925 BIO_set_flags(SSL_get_rbio(s
), BIO_FLAGS_READ
);
929 return dtls1_handle_timeout(s
);
932 int dtls1_get_queue_priority(unsigned short seq
, int is_ccs
)
935 * The index of the retransmission queue actually is the message sequence
936 * number, since the queue only contains messages of a single handshake.
937 * However, the ChangeCipherSpec has no message sequence number and so
938 * using only the sequence will result in the CCS and Finished having the
939 * same index. To prevent this, the sequence number is multiplied by 2.
940 * In case of a CCS 1 is subtracted. This does not only differ CSS and
941 * Finished, it also maintains the order of the index (important for
942 * priority queues) and fits in the unsigned short variable.
944 return seq
* 2 - is_ccs
;
947 int dtls1_retransmit_buffered_messages(SSL
*s
)
949 pqueue
*sent
= s
->d1
->sent_messages
;
955 iter
= pqueue_iterator(sent
);
957 for (item
= pqueue_next(&iter
); item
!= NULL
; item
= pqueue_next(&iter
)) {
958 frag
= (hm_fragment
*)item
->data
;
959 if (dtls1_retransmit_message(s
, (unsigned short)
960 dtls1_get_queue_priority
961 (frag
->msg_header
.seq
,
962 frag
->msg_header
.is_ccs
), &found
) <= 0)
969 int dtls1_buffer_message(SSL
*s
, int is_ccs
)
973 unsigned char seq64be
[8];
976 * this function is called immediately after a message has been
979 OPENSSL_assert(s
->init_off
== 0);
981 frag
= dtls1_hm_fragment_new(s
->init_num
, 0);
985 memcpy(frag
->fragment
, s
->init_buf
->data
, s
->init_num
);
988 /* For DTLS1_BAD_VER the header length is non-standard */
989 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
991 DTLS1_BAD_VER
) ? 3 : DTLS1_CCS_HEADER_LENGTH
)
992 == (unsigned int)s
->init_num
);
994 OPENSSL_assert(s
->d1
->w_msg_hdr
.msg_len
+
995 DTLS1_HM_HEADER_LENGTH
== (unsigned int)s
->init_num
);
998 frag
->msg_header
.msg_len
= s
->d1
->w_msg_hdr
.msg_len
;
999 frag
->msg_header
.seq
= s
->d1
->w_msg_hdr
.seq
;
1000 frag
->msg_header
.type
= s
->d1
->w_msg_hdr
.type
;
1001 frag
->msg_header
.frag_off
= 0;
1002 frag
->msg_header
.frag_len
= s
->d1
->w_msg_hdr
.msg_len
;
1003 frag
->msg_header
.is_ccs
= is_ccs
;
1005 /* save current state */
1006 frag
->msg_header
.saved_retransmit_state
.enc_write_ctx
= s
->enc_write_ctx
;
1007 frag
->msg_header
.saved_retransmit_state
.write_hash
= s
->write_hash
;
1008 frag
->msg_header
.saved_retransmit_state
.compress
= s
->compress
;
1009 frag
->msg_header
.saved_retransmit_state
.session
= s
->session
;
1010 frag
->msg_header
.saved_retransmit_state
.epoch
=
1011 DTLS_RECORD_LAYER_get_w_epoch(&s
->rlayer
);
1013 memset(seq64be
, 0, sizeof(seq64be
));
1016 char)(dtls1_get_queue_priority(frag
->msg_header
.seq
,
1017 frag
->msg_header
.is_ccs
) >> 8);
1020 char)(dtls1_get_queue_priority(frag
->msg_header
.seq
,
1021 frag
->msg_header
.is_ccs
));
1023 item
= pitem_new(seq64be
, frag
);
1025 dtls1_hm_fragment_free(frag
);
1029 pqueue_insert(s
->d1
->sent_messages
, item
);
1033 int dtls1_retransmit_message(SSL
*s
, unsigned short seq
, int *found
)
1036 /* XDTLS: for now assuming that read/writes are blocking */
1039 unsigned long header_length
;
1040 unsigned char seq64be
[8];
1041 struct dtls1_retransmit_state saved_state
;
1044 OPENSSL_assert(s->init_num == 0);
1045 OPENSSL_assert(s->init_off == 0);
1048 /* XDTLS: the requested message ought to be found, otherwise error */
1049 memset(seq64be
, 0, sizeof(seq64be
));
1050 seq64be
[6] = (unsigned char)(seq
>> 8);
1051 seq64be
[7] = (unsigned char)seq
;
1053 item
= pqueue_find(s
->d1
->sent_messages
, seq64be
);
1055 SSLerr(SSL_F_DTLS1_RETRANSMIT_MESSAGE
, ERR_R_INTERNAL_ERROR
);
1061 frag
= (hm_fragment
*)item
->data
;
1063 if (frag
->msg_header
.is_ccs
)
1064 header_length
= DTLS1_CCS_HEADER_LENGTH
;
1066 header_length
= DTLS1_HM_HEADER_LENGTH
;
1068 memcpy(s
->init_buf
->data
, frag
->fragment
,
1069 frag
->msg_header
.msg_len
+ header_length
);
1070 s
->init_num
= frag
->msg_header
.msg_len
+ header_length
;
1072 dtls1_set_message_header_int(s
, frag
->msg_header
.type
,
1073 frag
->msg_header
.msg_len
,
1074 frag
->msg_header
.seq
, 0,
1075 frag
->msg_header
.frag_len
);
1077 /* save current state */
1078 saved_state
.enc_write_ctx
= s
->enc_write_ctx
;
1079 saved_state
.write_hash
= s
->write_hash
;
1080 saved_state
.compress
= s
->compress
;
1081 saved_state
.session
= s
->session
;
1082 saved_state
.epoch
= DTLS_RECORD_LAYER_get_w_epoch(&s
->rlayer
);
1084 s
->d1
->retransmitting
= 1;
1086 /* restore state in which the message was originally sent */
1087 s
->enc_write_ctx
= frag
->msg_header
.saved_retransmit_state
.enc_write_ctx
;
1088 s
->write_hash
= frag
->msg_header
.saved_retransmit_state
.write_hash
;
1089 s
->compress
= frag
->msg_header
.saved_retransmit_state
.compress
;
1090 s
->session
= frag
->msg_header
.saved_retransmit_state
.session
;
1091 DTLS_RECORD_LAYER_set_saved_w_epoch(&s
->rlayer
,
1093 saved_retransmit_state
.epoch
);
1095 ret
= dtls1_do_write(s
, frag
->msg_header
.is_ccs
?
1096 SSL3_RT_CHANGE_CIPHER_SPEC
: SSL3_RT_HANDSHAKE
);
1098 /* restore current state */
1099 s
->enc_write_ctx
= saved_state
.enc_write_ctx
;
1100 s
->write_hash
= saved_state
.write_hash
;
1101 s
->compress
= saved_state
.compress
;
1102 s
->session
= saved_state
.session
;
1103 DTLS_RECORD_LAYER_set_saved_w_epoch(&s
->rlayer
, saved_state
.epoch
);
1105 s
->d1
->retransmitting
= 0;
1107 (void)BIO_flush(s
->wbio
);
1111 void dtls1_set_message_header(SSL
*s
,
1112 unsigned char mt
, size_t len
,
1113 size_t frag_off
, size_t frag_len
)
1115 if (frag_off
== 0) {
1116 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
1117 s
->d1
->next_handshake_write_seq
++;
1120 dtls1_set_message_header_int(s
, mt
, len
, s
->d1
->handshake_write_seq
,
1121 frag_off
, frag_len
);
1124 /* don't actually do the writing, wait till the MTU has been retrieved */
1126 dtls1_set_message_header_int(SSL
*s
, unsigned char mt
,
1127 size_t len
, unsigned short seq_num
,
1128 size_t frag_off
, size_t frag_len
)
1130 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1133 msg_hdr
->msg_len
= len
;
1134 msg_hdr
->seq
= seq_num
;
1135 msg_hdr
->frag_off
= frag_off
;
1136 msg_hdr
->frag_len
= frag_len
;
1140 dtls1_fix_message_header(SSL
*s
, size_t frag_off
, size_t frag_len
)
1142 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1144 msg_hdr
->frag_off
= frag_off
;
1145 msg_hdr
->frag_len
= frag_len
;
1148 static unsigned char *dtls1_write_message_header(SSL
*s
, unsigned char *p
)
1150 struct hm_header_st
*msg_hdr
= &s
->d1
->w_msg_hdr
;
1152 *p
++ = msg_hdr
->type
;
1153 l2n3(msg_hdr
->msg_len
, p
);
1155 s2n(msg_hdr
->seq
, p
);
1156 l2n3(msg_hdr
->frag_off
, p
);
1157 l2n3(msg_hdr
->frag_len
, p
);
1162 void dtls1_get_message_header(unsigned char *data
, struct hm_header_st
*msg_hdr
)
1164 memset(msg_hdr
, 0, sizeof(*msg_hdr
));
1165 msg_hdr
->type
= *(data
++);
1166 n2l3(data
, msg_hdr
->msg_len
);
1168 n2s(data
, msg_hdr
->seq
);
1169 n2l3(data
, msg_hdr
->frag_off
);
1170 n2l3(data
, msg_hdr
->frag_len
);
1173 int dtls1_set_handshake_header(SSL
*s
, WPACKET
*pkt
, int htype
)
1175 unsigned char *header
;
1177 if (htype
== SSL3_MT_CHANGE_CIPHER_SPEC
) {
1178 s
->d1
->handshake_write_seq
= s
->d1
->next_handshake_write_seq
;
1179 dtls1_set_message_header_int(s
, SSL3_MT_CCS
, 0,
1180 s
->d1
->handshake_write_seq
, 0, 0);
1181 if (!WPACKET_put_bytes_u8(pkt
, SSL3_MT_CCS
))
1184 dtls1_set_message_header(s
, htype
, 0, 0, 0);
1186 * We allocate space at the start for the message header. This gets
1189 if (!WPACKET_allocate_bytes(pkt
, DTLS1_HM_HEADER_LENGTH
, &header
)
1190 || !WPACKET_start_sub_packet(pkt
))
1197 int dtls1_close_construct_packet(SSL
*s
, WPACKET
*pkt
, int htype
)
1201 if ((htype
!= SSL3_MT_CHANGE_CIPHER_SPEC
&& !WPACKET_close(pkt
))
1202 || !WPACKET_get_length(pkt
, &msglen
)
1203 || msglen
> INT_MAX
)
1206 if (htype
!= SSL3_MT_CHANGE_CIPHER_SPEC
) {
1207 s
->d1
->w_msg_hdr
.msg_len
= msglen
- DTLS1_HM_HEADER_LENGTH
;
1208 s
->d1
->w_msg_hdr
.frag_len
= msglen
- DTLS1_HM_HEADER_LENGTH
;
1210 s
->init_num
= (int)msglen
;
1213 if (htype
!= DTLS1_MT_HELLO_VERIFY_REQUEST
) {
1214 /* Buffer the message to handle re-xmits */
1215 if (!dtls1_buffer_message(s
, htype
== SSL3_MT_CHANGE_CIPHER_SPEC