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/evp.h>
121 #include <openssl/buffer.h>
122 #include <openssl/pqueue.h>
123 #include <openssl/rand.h>
125 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
127 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
128 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
129 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
130 unsigned int *is_next_epoch);
132 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
133 unsigned short *priority,
134 unsigned long *offset);
136 static int dtls1_buffer_record(SSL *s, record_pqueue *q, PQ_64BIT * priority);
137 static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap);
138 #if PQ_64BIT_IS_INTEGER
139 static PQ_64BIT bytes_to_long_long(unsigned char *bytes, PQ_64BIT * num);
142 /* copy buffered record into SSL structure */
143 static int dtls1_copy_record(SSL *s, pitem *item)
145 DTLS1_RECORD_DATA *rdata;
147 rdata = (DTLS1_RECORD_DATA *)item->data;
149 if (s->s3->rbuf.buf != NULL)
150 OPENSSL_free(s->s3->rbuf.buf);
152 s->packet = rdata->packet;
153 s->packet_length = rdata->packet_length;
154 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
155 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
157 /* Set proper sequence number for mac calculation */
158 memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6);
164 dtls1_buffer_record(SSL *s, record_pqueue *queue, PQ_64BIT * priority)
166 DTLS1_RECORD_DATA *rdata;
169 /* Limit the size of the queue to prevent DOS attacks */
170 if (pqueue_size(queue->q) >= 100)
173 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
174 item = pitem_new(*priority, rdata);
175 if (rdata == NULL || item == NULL) {
181 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
185 rdata->packet = s->packet;
186 rdata->packet_length = s->packet_length;
187 memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
188 memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
192 /* insert should not fail, since duplicates are dropped */
193 if (pqueue_insert(queue->q, item) == NULL) {
200 s->packet_length = 0;
201 memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
202 memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
204 if (!ssl3_setup_buffers(s)) {
205 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
214 static int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
218 item = pqueue_pop(queue->q);
220 dtls1_copy_record(s, item);
222 OPENSSL_free(item->data);
232 * retrieve a buffered record that belongs to the new epoch, i.e., not
235 #define dtls1_get_unprocessed_record(s) \
236 dtls1_retrieve_buffered_record((s), \
237 &((s)->d1->unprocessed_rcds))
240 * retrieve a buffered record that belongs to the current epoch, ie,
243 #define dtls1_get_processed_record(s) \
244 dtls1_retrieve_buffered_record((s), \
245 &((s)->d1->processed_rcds))
247 static int dtls1_process_buffered_records(SSL *s)
252 DTLS1_BITMAP *bitmap;
253 unsigned int is_next_epoch;
256 item = pqueue_peek(s->d1->unprocessed_rcds.q);
258 /* Check if epoch is current. */
259 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
260 return 1; /* Nothing to do. */
267 * We've still got data from the current packet to read. There could
268 * be a record from the new epoch in it - so don't overwrite it
269 * with the unprocessed records yet (we'll do it when we've
270 * finished reading the current packet).
276 /* Process all the records. */
277 while (pqueue_peek(s->d1->unprocessed_rcds.q)) {
278 dtls1_get_unprocessed_record(s);
279 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
280 if (bitmap == NULL) {
282 * Should not happen. This will only ever be NULL when the
283 * current record is from a different epoch. But that cannot
284 * be the case because we already checked the epoch above
286 SSLerr(SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS,
287 ERR_R_INTERNAL_ERROR);
292 * Check whether this is a repeat, or aged record. We did this
293 * check once already when we first received the record - but
294 * we might have updated the window since then due to
295 * records we subsequently processed.
297 replayok = dtls1_record_replay_check(s, bitmap);
300 if (!replayok || !dtls1_process_record(s, bitmap)) {
301 /* dump this record */
303 s->packet_length = 0;
307 if (dtls1_buffer_record(s, &(s->d1->processed_rcds),
308 &s->s3->rrec.seq_num) < 0)
314 * sync epoch numbers once all the unprocessed records have been
317 s->d1->processed_rcds.epoch = s->d1->r_epoch;
318 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
325 static int dtls1_get_buffered_record(SSL *s)
329 (((PQ_64BIT) s->d1->handshake_read_seq) << 32) |
330 ((PQ_64BIT) s->d1->r_msg_hdr.frag_off);
332 /* if we're not (re)negotiating, nothing buffered */
336 item = pqueue_peek(s->d1->rcvd_records);
337 if (item && item->priority == priority) {
339 * Check if we've received the record of interest. It must be a
340 * handshake record, since data records as passed up without
343 DTLS1_RECORD_DATA *rdata;
344 item = pqueue_pop(s->d1->rcvd_records);
345 rdata = (DTLS1_RECORD_DATA *)item->data;
347 if (s->s3->rbuf.buf != NULL)
348 OPENSSL_free(s->s3->rbuf.buf);
350 s->packet = rdata->packet;
351 s->packet_length = rdata->packet_length;
352 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
353 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
355 OPENSSL_free(item->data);
358 /* s->d1->next_expected_seq_num++; */
367 static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap)
373 unsigned int mac_size, orig_len;
374 unsigned char md[EVP_MAX_MD_SIZE];
380 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
381 * and we have that many bytes in s->packet
383 rr->input = &(s->packet[DTLS1_RT_HEADER_LENGTH]);
386 * ok, we can now read from 's->packet' data into 'rr' rr->input points
387 * at rr->length bytes, which need to be copied into rr->data by either
388 * the decryption or by the decompression When the data is 'copied' into
389 * the rr->data buffer, rr->input will be pointed at the new buffer
393 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
394 * bytes of encrypted compressed stuff.
397 /* check is not needed I believe */
398 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
399 al = SSL_AD_RECORD_OVERFLOW;
400 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
404 /* decrypt in place in 'rr->input' */
405 rr->data = rr->input;
407 enc_err = s->method->ssl3_enc->enc(s, 0);
410 * 0: (in non-constant time) if the record is publically invalid.
411 * 1: if the padding is valid
412 * -1: if the padding is invalid
415 /* For DTLS we simply ignore bad packets. */
417 s->packet_length = 0;
421 printf("dec %d\n", rr->length);
424 for (z = 0; z < rr->length; z++)
425 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
430 /* r->length is now the compressed data plus mac */
431 if ((sess != NULL) && (s->enc_read_ctx != NULL) && (s->read_hash != NULL)) {
432 /* s->read_hash != NULL => mac_size != -1 */
433 unsigned char *mac = NULL;
434 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
435 mac_size = EVP_MD_size(s->read_hash);
436 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
439 * kludge: *_cbc_remove_padding passes padding length in rr->type
441 orig_len = rr->length + ((unsigned int)rr->type >> 8);
444 * orig_len is the length of the record before any padding was
445 * removed. This is public information, as is the MAC in use,
446 * therefore we can safely process the record in a different amount
447 * of time if it's too short to possibly contain a MAC.
449 if (orig_len < mac_size ||
450 /* CBC records must have a padding length byte too. */
451 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
452 orig_len < mac_size + 1)) {
453 al = SSL_AD_DECODE_ERROR;
454 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT);
458 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
460 * We update the length so that the TLS header bytes can be
461 * constructed correctly but we need to extract the MAC in
462 * constant time from within the record, without leaking the
463 * contents of the padding bytes.
466 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
467 rr->length -= mac_size;
470 * In this case there's no padding, so |orig_len| equals
471 * |rec->length| and we checked that there's enough bytes for
474 rr->length -= mac_size;
475 mac = &rr->data[rr->length];
478 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
479 if (i < 0 || mac == NULL
480 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
482 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
487 /* decryption failed, silently discard message */
489 s->packet_length = 0;
493 /* r->length is now just compressed */
494 if (s->expand != NULL) {
495 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
496 al = SSL_AD_RECORD_OVERFLOW;
497 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,
498 SSL_R_COMPRESSED_LENGTH_TOO_LONG);
501 if (!ssl3_do_uncompress(s)) {
502 al = SSL_AD_DECOMPRESSION_FAILURE;
503 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION);
508 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) {
509 al = SSL_AD_RECORD_OVERFLOW;
510 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
516 * So at this point the following is true
517 * ssl->s3->rrec.type is the type of record
518 * ssl->s3->rrec.length == number of bytes in record
519 * ssl->s3->rrec.off == offset to first valid byte
520 * ssl->s3->rrec.data == where to take bytes from, increment
524 /* we have pulled in a full packet so zero things */
525 s->packet_length = 0;
527 /* Mark receipt of record. */
528 dtls1_record_bitmap_update(s, bitmap);
533 ssl3_send_alert(s, SSL3_AL_FATAL, al);
539 * Call this to get a new input record.
540 * It will return <= 0 if more data is needed, normally due to an error
541 * or non-blocking IO.
542 * When it finishes, one packet has been decoded and can be found in
543 * ssl->s3->rrec.type - is the type of record
544 * ssl->s3->rrec.data, - data
545 * ssl->s3->rrec.length, - number of bytes
547 /* used only by dtls1_read_bytes */
548 int dtls1_get_record(SSL *s)
550 int ssl_major, ssl_minor;
553 unsigned char *p = NULL;
554 unsigned short version;
555 DTLS1_BITMAP *bitmap;
556 unsigned int is_next_epoch;
562 * The epoch may have changed. If so, process all the pending records.
563 * This is a non-blocking operation.
565 dtls1_process_buffered_records(s);
567 /* if we're renegotiating, then there may be buffered records */
568 if (dtls1_get_processed_record(s))
571 /* get something from the wire */
572 /* check if we have the header */
573 if ((s->rstate != SSL_ST_READ_BODY) ||
574 (s->packet_length < DTLS1_RT_HEADER_LENGTH)) {
575 n = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
576 /* read timeout is handled by dtls1_read_bytes */
578 return (n); /* error or non-blocking */
580 /* this packet contained a partial record, dump it */
581 if (s->packet_length != DTLS1_RT_HEADER_LENGTH) {
582 s->packet_length = 0;
586 s->rstate = SSL_ST_READ_BODY;
590 /* Pull apart the header into the DTLS1_RECORD */
594 version = (ssl_major << 8) | ssl_minor;
596 /* sequence number is 64 bits, with top 2 bytes = epoch */
599 memcpy(&(s->s3->read_sequence[2]), p, 6);
604 /* Lets check version */
605 if (!s->first_packet) {
606 if (version != s->version && version != DTLS1_BAD_VER) {
607 /* unexpected version, silently discard */
609 s->packet_length = 0;
614 if ((version & 0xff00) != (DTLS1_VERSION & 0xff00) &&
615 (version & 0xff00) != (DTLS1_BAD_VER & 0xff00)) {
616 /* wrong version, silently discard record */
618 s->packet_length = 0;
622 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
623 /* record too long, silently discard it */
625 s->packet_length = 0;
629 s->client_version = version;
630 /* now s->rstate == SSL_ST_READ_BODY */
633 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
635 if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) {
636 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
638 n = ssl3_read_n(s, i, i, 1);
639 /* this packet contained a partial record, dump it */
642 s->packet_length = 0;
647 * now n == rr->length, and s->packet_length ==
648 * DTLS1_RT_HEADER_LENGTH + rr->length
651 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
653 /* match epochs. NULL means the packet is dropped on the floor */
654 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
655 if (bitmap == NULL) {
657 s->packet_length = 0; /* dump this record */
658 goto again; /* get another record */
662 * Check whether this is a repeat, or aged record. Don't check if we're
663 * listening and this message is a ClientHello. They can look as if
664 * they're replayed, since they arrive from different connections and
665 * would be dropped unnecessarily.
667 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
668 s->packet_length > DTLS1_RT_HEADER_LENGTH &&
669 s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
670 !dtls1_record_replay_check(s, bitmap)) {
672 s->packet_length = 0; /* dump this record */
673 goto again; /* get another record */
676 /* just read a 0 length packet */
681 * If this record is from the next epoch (either HM or ALERT), and a
682 * handshake is currently in progress, buffer it since it cannot be
683 * processed at this time. However, do not buffer anything while
687 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) {
688 if (dtls1_buffer_record
689 (s, &(s->d1->unprocessed_rcds), &rr->seq_num) < 0)
693 s->packet_length = 0;
697 if (!dtls1_process_record(s, bitmap)) {
699 s->packet_length = 0; /* dump this record */
700 goto again; /* get another record */
708 * Return up to 'len' payload bytes received in 'type' records.
709 * 'type' is one of the following:
711 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
712 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
713 * - 0 (during a shutdown, no data has to be returned)
715 * If we don't have stored data to work from, read a SSL/TLS record first
716 * (possibly multiple records if we still don't have anything to return).
718 * This function must handle any surprises the peer may have for us, such as
719 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
720 * a surprise, but handled as if it were), or renegotiation requests.
721 * Also if record payloads contain fragments too small to process, we store
722 * them until there is enough for the respective protocol (the record protocol
723 * may use arbitrary fragmentation and even interleaving):
724 * Change cipher spec protocol
725 * just 1 byte needed, no need for keeping anything stored
727 * 2 bytes needed (AlertLevel, AlertDescription)
729 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
730 * to detect unexpected Client Hello and Hello Request messages
731 * here, anything else is handled by higher layers
732 * Application data protocol
733 * none of our business
735 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
740 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
742 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
743 if (!ssl3_setup_buffers(s))
746 /* XXX: check what the second '&& type' is about */
747 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
748 (type != SSL3_RT_HANDSHAKE) && type) ||
749 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
750 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
755 * check whether there's a handshake message (client hello?) waiting
757 if ((ret = have_handshake_fragment(s, type, buf, len, peek)))
761 * Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
764 if (!s->in_handshake && SSL_in_init(s)) {
765 /* type == SSL3_RT_APPLICATION_DATA */
766 i = s->handshake_func(s);
770 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
776 s->rwstate = SSL_NOTHING;
779 * s->s3->rrec.type - is the type of record
780 * s->s3->rrec.data, - data
781 * s->s3->rrec.off, - offset into 'data' for next read
782 * s->s3->rrec.length, - number of bytes.
787 * We are not handshaking and have no data yet, so process data buffered
788 * during the last handshake in advance, if any.
790 if (s->state == SSL_ST_OK && rr->length == 0) {
792 item = pqueue_pop(s->d1->buffered_app_data.q);
794 dtls1_copy_record(s, item);
796 OPENSSL_free(item->data);
801 /* Check for timeout */
802 if (dtls1_handle_timeout(s) > 0)
805 /* get new packet if necessary */
806 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
807 ret = dtls1_get_record(s);
809 ret = dtls1_read_failed(s, ret);
810 /* anything other than a timeout is an error */
818 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) {
824 * Reset the count of consecutive warning alerts if we've got a non-empty
825 * record that isn't an alert.
827 if (rr->type != SSL3_RT_ALERT && rr->length != 0)
828 s->s3->alert_count = 0;
830 /* we now have a packet which can be read and processed */
832 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
833 * reset by ssl3_get_finished */
834 && (rr->type != SSL3_RT_HANDSHAKE)) {
836 * We now have application data between CCS and Finished. Most likely
837 * the packets were reordered on their way, so buffer the application
838 * data for later processing rather than dropping the connection.
840 dtls1_buffer_record(s, &(s->d1->buffered_app_data), &rr->seq_num);
846 * If the other end has shut down, throw anything we read away (even in
849 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
851 s->rwstate = SSL_NOTHING;
855 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
856 * SSL3_RT_HANDSHAKE */
858 * make sure that we are not getting application data when we are
859 * doing a handshake for the first time
861 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
862 (s->enc_read_ctx == NULL)) {
863 al = SSL_AD_UNEXPECTED_MESSAGE;
864 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
871 if ((unsigned int)len > rr->length)
874 n = (unsigned int)len;
876 memcpy(buf, &(rr->data[rr->off]), n);
880 if (rr->length == 0) {
881 s->rstate = SSL_ST_READ_HEADER;
889 * If we get here, then type != rr->type; if we have a handshake message,
890 * then it was unexpected (Hello Request or Client Hello).
894 * In case of record types for which we have 'fragment' storage, fill
895 * that so that we can process the data at a fixed place.
898 unsigned int k, dest_maxlen = 0;
899 unsigned char *dest = NULL;
900 unsigned int *dest_len = NULL;
902 if (rr->type == SSL3_RT_HANDSHAKE) {
903 dest_maxlen = sizeof s->d1->handshake_fragment;
904 dest = s->d1->handshake_fragment;
905 dest_len = &s->d1->handshake_fragment_len;
906 } else if (rr->type == SSL3_RT_ALERT) {
907 dest_maxlen = sizeof(s->d1->alert_fragment);
908 dest = s->d1->alert_fragment;
909 dest_len = &s->d1->alert_fragment_len;
911 /* else it's a CCS message, or application data or wrong */
912 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) {
914 * Application data while renegotiating is allowed. Try again
917 if (rr->type == SSL3_RT_APPLICATION_DATA) {
919 s->s3->in_read_app_data = 2;
920 bio = SSL_get_rbio(s);
921 s->rwstate = SSL_READING;
922 BIO_clear_retry_flags(bio);
923 BIO_set_retry_read(bio);
927 /* Not certain if this is the right error handling */
928 al = SSL_AD_UNEXPECTED_MESSAGE;
929 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
933 if (dest_maxlen > 0) {
935 * XDTLS: In a pathalogical case, the Client Hello may be
936 * fragmented--don't always expect dest_maxlen bytes
938 if (rr->length < dest_maxlen) {
939 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
941 * for normal alerts rr->length is 2, while
942 * dest_maxlen is 7 if we were to handle this
943 * non-existing alert...
947 s->rstate = SSL_ST_READ_HEADER;
952 /* now move 'n' bytes: */
953 for (k = 0; k < dest_maxlen; k++) {
954 dest[k] = rr->data[rr->off++];
957 *dest_len = dest_maxlen;
962 * s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
963 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
964 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
967 /* If we are a client, check for an incoming 'Hello Request': */
969 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
970 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
971 (s->session != NULL) && (s->session->cipher != NULL)) {
972 s->d1->handshake_fragment_len = 0;
974 if ((s->d1->handshake_fragment[1] != 0) ||
975 (s->d1->handshake_fragment[2] != 0) ||
976 (s->d1->handshake_fragment[3] != 0)) {
977 al = SSL_AD_DECODE_ERROR;
978 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
983 * no need to check sequence number on HELLO REQUEST messages
987 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
988 s->d1->handshake_fragment, 4, s,
989 s->msg_callback_arg);
991 if (SSL_is_init_finished(s) &&
992 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
993 !s->s3->renegotiate) {
994 s->d1->handshake_read_seq++;
996 if (ssl3_renegotiate_check(s)) {
997 i = s->handshake_func(s);
1001 SSLerr(SSL_F_DTLS1_READ_BYTES,
1002 SSL_R_SSL_HANDSHAKE_FAILURE);
1006 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1007 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1010 * In the case where we try to read application data,
1011 * but we trigger an SSL handshake, we return -1 with
1012 * the retry option set. Otherwise renegotiation may
1013 * cause nasty problems in the blocking world
1015 s->rwstate = SSL_READING;
1016 bio = SSL_get_rbio(s);
1017 BIO_clear_retry_flags(bio);
1018 BIO_set_retry_read(bio);
1025 * we either finished a handshake or ignored the request, now try
1026 * again to obtain the (application) data we were asked for
1031 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
1032 int alert_level = s->d1->alert_fragment[0];
1033 int alert_descr = s->d1->alert_fragment[1];
1035 s->d1->alert_fragment_len = 0;
1037 if (s->msg_callback)
1038 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1039 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1041 if (s->info_callback != NULL)
1042 cb = s->info_callback;
1043 else if (s->ctx->info_callback != NULL)
1044 cb = s->ctx->info_callback;
1047 j = (alert_level << 8) | alert_descr;
1048 cb(s, SSL_CB_READ_ALERT, j);
1051 if (alert_level == 1) { /* warning */
1052 s->s3->warn_alert = alert_descr;
1054 s->s3->alert_count++;
1055 if (s->s3->alert_count == MAX_WARN_ALERT_COUNT) {
1056 al = SSL_AD_UNEXPECTED_MESSAGE;
1057 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS);
1061 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1062 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1066 /* XXX: this is a possible improvement in the future */
1067 /* now check if it's a missing record */
1068 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
1070 unsigned int frag_off;
1071 unsigned char *p = &(s->d1->alert_fragment[2]);
1076 dtls1_retransmit_message(s,
1077 dtls1_get_queue_priority
1078 (frag->msg_header.seq, 0), frag_off,
1080 if (!found && SSL_in_init(s)) {
1082 * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
1085 * requested a message not yet sent, send an alert
1088 ssl3_send_alert(s, SSL3_AL_WARNING,
1089 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1093 } else if (alert_level == 2) { /* fatal */
1096 s->rwstate = SSL_NOTHING;
1097 s->s3->fatal_alert = alert_descr;
1098 SSLerr(SSL_F_DTLS1_READ_BYTES,
1099 SSL_AD_REASON_OFFSET + alert_descr);
1100 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1101 ERR_add_error_data(2, "SSL alert number ", tmp);
1102 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1103 SSL_CTX_remove_session(s->ctx, s->session);
1106 al = SSL_AD_ILLEGAL_PARAMETER;
1107 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
1114 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
1116 s->rwstate = SSL_NOTHING;
1121 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1122 struct ccs_header_st ccs_hdr;
1123 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1125 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1128 * 'Change Cipher Spec' is just a single byte, so we know exactly
1129 * what the record payload has to look like
1131 /* XDTLS: check that epoch is consistent */
1132 if (s->client_version == DTLS1_BAD_VER || s->version == DTLS1_BAD_VER)
1135 if ((rr->length != ccs_hdr_len) || (rr->off != 0)
1136 || (rr->data[0] != SSL3_MT_CCS)) {
1137 i = SSL_AD_ILLEGAL_PARAMETER;
1138 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1144 if (s->msg_callback)
1145 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1146 rr->data, 1, s, s->msg_callback_arg);
1149 * We can't process a CCS now, because previous handshake messages
1150 * are still missing, so just drop it.
1152 if (!s->d1->change_cipher_spec_ok) {
1156 s->d1->change_cipher_spec_ok = 0;
1158 s->s3->change_cipher_spec = 1;
1159 if (!ssl3_do_change_cipher_spec(s))
1162 /* do this whenever CCS is processed */
1163 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1165 if (s->client_version == DTLS1_BAD_VER)
1166 s->d1->handshake_read_seq++;
1172 * Unexpected handshake message (Client Hello, or protocol violation)
1174 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1176 struct hm_header_st msg_hdr;
1178 /* this may just be a stale retransmit */
1179 dtls1_get_message_header(rr->data, &msg_hdr);
1180 if (rr->epoch != s->d1->r_epoch) {
1186 * If we are server, we may have a repeated FINISHED of the client
1187 * here, then retransmit our CCS and FINISHED.
1189 if (msg_hdr.type == SSL3_MT_FINISHED) {
1190 if (dtls1_check_timeout_num(s) < 0)
1193 dtls1_retransmit_buffered_messages(s);
1198 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1199 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1200 #if 0 /* worked only because C operator preferences
1201 * are not as expected (and because this is
1202 * not really needed for clients except for
1203 * detecting protocol violations): */
1204 s->state = SSL_ST_BEFORE | (s->server)
1205 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1207 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1211 i = s->handshake_func(s);
1215 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1219 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1220 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1223 * In the case where we try to read application data, but we
1224 * trigger an SSL handshake, we return -1 with the retry
1225 * option set. Otherwise renegotiation may cause nasty
1226 * problems in the blocking world
1228 s->rwstate = SSL_READING;
1229 bio = SSL_get_rbio(s);
1230 BIO_clear_retry_flags(bio);
1231 BIO_set_retry_read(bio);
1240 #ifndef OPENSSL_NO_TLS
1241 /* TLS just ignores unknown message types */
1242 if (s->version == TLS1_VERSION) {
1247 al = SSL_AD_UNEXPECTED_MESSAGE;
1248 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1250 case SSL3_RT_CHANGE_CIPHER_SPEC:
1252 case SSL3_RT_HANDSHAKE:
1254 * we already handled all of these, with the possible exception of
1255 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1256 * happen when type != rr->type
1258 al = SSL_AD_UNEXPECTED_MESSAGE;
1259 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
1261 case SSL3_RT_APPLICATION_DATA:
1263 * At this point, we were expecting handshake data, but have
1264 * application data. If the library was running inside ssl3_read()
1265 * (i.e. in_read_app_data is set) and it makes sense to read
1266 * application data at this point (session renegotiation not yet
1267 * started), we will indulge it.
1269 if (s->s3->in_read_app_data &&
1270 (s->s3->total_renegotiations != 0) &&
1271 (((s->state & SSL_ST_CONNECT) &&
1272 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1273 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1274 ) || ((s->state & SSL_ST_ACCEPT) &&
1275 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1276 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1279 s->s3->in_read_app_data = 2;
1282 al = SSL_AD_UNEXPECTED_MESSAGE;
1283 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1290 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1295 int dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1299 if (SSL_in_init(s) && !s->in_handshake) {
1300 i = s->handshake_func(s);
1304 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,
1305 SSL_R_SSL_HANDSHAKE_FAILURE);
1310 if (len > SSL3_RT_MAX_PLAIN_LENGTH) {
1311 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, SSL_R_DTLS_MESSAGE_TOO_BIG);
1315 i = dtls1_write_bytes(s, type, buf_, len);
1320 * this only happens when a client hello is received and a handshake
1324 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1328 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1329 /* (partially) satisfy request from storage */
1331 unsigned char *src = s->d1->handshake_fragment;
1332 unsigned char *dst = buf;
1337 while ((len > 0) && (s->d1->handshake_fragment_len > 0)) {
1340 s->d1->handshake_fragment_len--;
1343 /* move any remaining fragment bytes: */
1344 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1345 s->d1->handshake_fragment[k] = *src++;
1353 * Call this to write data in records of type 'type' It will return <= 0 if
1354 * not all data has been sent or non-blocking IO.
1356 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1360 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1361 s->rwstate = SSL_NOTHING;
1362 i = do_dtls1_write(s, type, buf, len, 0);
1366 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
1367 unsigned int len, int create_empty_fragment)
1369 unsigned char *p, *pseq;
1370 int i, mac_size, clear = 0;
1378 * first check if there is a SSL3_BUFFER still being written out. This
1379 * will happen with non blocking IO
1381 if (s->s3->wbuf.left != 0) {
1382 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1383 return (ssl3_write_pending(s, type, buf, len));
1386 /* If we have an alert to send, lets send it */
1387 if (s->s3->alert_dispatch) {
1388 i = s->method->ssl_dispatch_alert(s);
1391 /* if it went, fall through and send more stuff */
1394 if (len == 0 && !create_empty_fragment)
1397 wr = &(s->s3->wrec);
1398 wb = &(s->s3->wbuf);
1401 if ((sess == NULL) ||
1402 (s->enc_write_ctx == NULL) || (s->write_hash == NULL))
1408 mac_size = EVP_MD_size(s->write_hash);
1410 /* DTLS implements explicit IV, so no need for empty fragments */
1413 * 'create_empty_fragment' is true only when this function calls itself
1415 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1416 && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1419 * countermeasure against known-IV weakness in CBC ciphersuites (see
1420 * http://www.openssl.org/~bodo/tls-cbc.txt)
1423 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
1425 * recursive function call with 'create_empty_fragment' set; this
1426 * prepares and buffers the data for an empty fragment (these
1427 * 'prefix_len' bytes are sent out later together with the actual
1430 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1431 if (prefix_len <= 0)
1434 if (s->s3->wbuf.len <
1435 (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) {
1436 /* insufficient space */
1437 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1442 s->s3->empty_fragment_done = 1;
1446 p = wb->buf + prefix_len;
1448 /* write the header */
1450 *(p++) = type & 0xff;
1453 if (s->client_version == DTLS1_BAD_VER)
1454 *(p++) = DTLS1_BAD_VER >> 8, *(p++) = DTLS1_BAD_VER & 0xff;
1456 *(p++) = (s->version >> 8), *(p++) = s->version & 0xff;
1458 /* field where we are to write out packet epoch, seq num and len */
1462 /* lets setup the record stuff. */
1465 * Make space for the explicit IV in case of CBC. (this is a bit of a
1466 * boundary violation, but what the heck).
1468 if (s->enc_write_ctx &&
1469 (EVP_CIPHER_mode(s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE))
1470 bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
1474 wr->data = p + bs; /* make room for IV in case of CBC */
1475 wr->length = (int)len;
1476 wr->input = (unsigned char *)buf;
1479 * we now 'read' from wr->input, wr->length bytes into wr->data
1482 /* first we compress */
1483 if (s->compress != NULL) {
1484 if (!ssl3_do_compress(s)) {
1485 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE);
1489 memcpy(wr->data, wr->input, wr->length);
1490 wr->input = wr->data;
1494 * we should still have the output to wr->data and the input from
1495 * wr->input. Length should be wr->length. wr->data still points in the
1499 if (mac_size != 0) {
1500 s->method->ssl3_enc->mac(s, &(p[wr->length + bs]), 1);
1501 wr->length += mac_size;
1504 /* this is true regardless of mac size */
1508 /* ssl3_enc can only have an error on read */
1509 if (bs) { /* bs != 0 in case of CBC */
1510 RAND_pseudo_bytes(p, bs);
1512 * master IV and last CBC residue stand for the rest of randomness
1517 s->method->ssl3_enc->enc(s, 1);
1519 /* record length after mac and block padding */
1521 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
1525 /* there's only one epoch between handshake and app data */
1527 s2n(s->d1->w_epoch, pseq);
1531 * else s2n(s->d1->handshake_epoch, pseq);
1534 memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1536 s2n(wr->length, pseq);
1539 * we should now have wr->data pointing to the encrypted data, which is
1542 wr->type = type; /* not needed but helps for debugging */
1543 wr->length += DTLS1_RT_HEADER_LENGTH;
1545 #if 0 /* this is now done at the message layer */
1546 /* buffer the record, making it easy to handle retransmits */
1547 if (type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1548 dtls1_buffer_record(s, wr->data, wr->length,
1549 *((PQ_64BIT *) & (s->s3->write_sequence[0])));
1552 ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1554 if (create_empty_fragment) {
1556 * we are in a recursive call; just return the length, don't write
1562 /* now let's set up wb */
1563 wb->left = prefix_len + wr->length;
1567 * memorize arguments so that ssl3_write_pending can detect bad write
1570 s->s3->wpend_tot = len;
1571 s->s3->wpend_buf = buf;
1572 s->s3->wpend_type = type;
1573 s->s3->wpend_ret = len;
1575 /* we now just need to write the buffer */
1576 return ssl3_write_pending(s, type, buf, len);
1581 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1583 #if PQ_64BIT_IS_INTEGER
1584 PQ_64BIT mask = 0x0000000000000001L;
1586 PQ_64BIT rcd_num, tmp;
1588 pq_64bit_init(&rcd_num);
1589 pq_64bit_init(&tmp);
1591 /* this is the sequence number for the record just read */
1592 pq_64bit_bin2num(&rcd_num, s->s3->read_sequence, 8);
1594 if (pq_64bit_gt(&rcd_num, &(bitmap->max_seq_num)) ||
1595 pq_64bit_eq(&rcd_num, &(bitmap->max_seq_num))) {
1596 pq_64bit_assign(&s->s3->rrec.seq_num, &rcd_num);
1597 pq_64bit_free(&rcd_num);
1598 pq_64bit_free(&tmp);
1599 return 1; /* this record is new */
1602 pq_64bit_sub(&tmp, &(bitmap->max_seq_num), &rcd_num);
1604 if (pq_64bit_get_word(&tmp) > bitmap->length) {
1605 pq_64bit_free(&rcd_num);
1606 pq_64bit_free(&tmp);
1607 return 0; /* stale, outside the window */
1609 #if PQ_64BIT_IS_BIGNUM
1612 pq_64bit_sub(&tmp, &(bitmap->max_seq_num), &rcd_num);
1613 pq_64bit_sub_word(&tmp, 1);
1614 offset = pq_64bit_get_word(&tmp);
1615 if (pq_64bit_is_bit_set(&(bitmap->map), offset)) {
1616 pq_64bit_free(&rcd_num);
1617 pq_64bit_free(&tmp);
1622 mask <<= (bitmap->max_seq_num - rcd_num - 1);
1623 if (bitmap->map & mask)
1624 return 0; /* record previously received */
1627 pq_64bit_assign(&s->s3->rrec.seq_num, &rcd_num);
1628 pq_64bit_free(&rcd_num);
1629 pq_64bit_free(&tmp);
1633 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1640 pq_64bit_init(&rcd_num);
1641 pq_64bit_init(&tmp);
1643 pq_64bit_bin2num(&rcd_num, s->s3->read_sequence, 8);
1646 * unfortunate code complexity due to 64-bit manipulation support on
1649 if (pq_64bit_gt(&rcd_num, &(bitmap->max_seq_num)) ||
1650 pq_64bit_eq(&rcd_num, &(bitmap->max_seq_num))) {
1651 pq_64bit_sub(&tmp, &rcd_num, &(bitmap->max_seq_num));
1652 pq_64bit_add_word(&tmp, 1);
1654 shift = (unsigned int)pq_64bit_get_word(&tmp);
1656 pq_64bit_lshift(&(tmp), &(bitmap->map), shift);
1657 pq_64bit_assign(&(bitmap->map), &tmp);
1659 pq_64bit_set_bit(&(bitmap->map), 0);
1660 pq_64bit_add_word(&rcd_num, 1);
1661 pq_64bit_assign(&(bitmap->max_seq_num), &rcd_num);
1663 pq_64bit_assign_word(&tmp, 1);
1664 pq_64bit_lshift(&tmp, &tmp, bitmap->length);
1665 ctx = pq_64bit_ctx_new(&ctx);
1666 pq_64bit_mod(&(bitmap->map), &(bitmap->map), &tmp, ctx);
1667 pq_64bit_ctx_free(ctx);
1669 pq_64bit_sub(&tmp, &(bitmap->max_seq_num), &rcd_num);
1670 pq_64bit_sub_word(&tmp, 1);
1671 shift = (unsigned int)pq_64bit_get_word(&tmp);
1673 pq_64bit_set_bit(&(bitmap->map), shift);
1676 pq_64bit_free(&rcd_num);
1677 pq_64bit_free(&tmp);
1680 int dtls1_dispatch_alert(SSL *s)
1683 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1684 unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1685 unsigned char *ptr = &buf[0];
1687 s->s3->alert_dispatch = 0;
1689 memset(buf, 0x00, sizeof(buf));
1690 *ptr++ = s->s3->send_alert[0];
1691 *ptr++ = s->s3->send_alert[1];
1693 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1694 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
1695 s2n(s->d1->handshake_read_seq, ptr);
1697 if (s->d1->r_msg_hdr.frag_off == 0)
1699 * waiting for a new msg
1702 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1707 "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",
1708 s->d1->handshake_read_seq, s->d1->r_msg_hdr.seq);
1710 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1714 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1716 s->s3->alert_dispatch = 1;
1717 /* fprintf( stderr, "not done with alert\n" ); */
1719 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1720 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1721 || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1724 (void)BIO_flush(s->wbio);
1726 if (s->msg_callback)
1727 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1728 2, s, s->msg_callback_arg);
1730 if (s->info_callback != NULL)
1731 cb = s->info_callback;
1732 else if (s->ctx->info_callback != NULL)
1733 cb = s->ctx->info_callback;
1736 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1737 cb(s, SSL_CB_WRITE_ALERT, j);
1743 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1744 unsigned int *is_next_epoch)
1749 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1750 if (rr->epoch == s->d1->r_epoch)
1751 return &s->d1->bitmap;
1754 * Only HM and ALERT messages can be from the next epoch and only if we
1755 * have already processed all of the unprocessed records from the last
1758 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1759 s->d1->unprocessed_rcds.epoch != s->d1->r_epoch &&
1760 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1762 return &s->d1->next_bitmap;
1770 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
1771 unsigned short *priority, unsigned long *offset)
1774 /* alerts are passed up immediately */
1775 if (rr->type == SSL3_RT_APPLICATION_DATA || rr->type == SSL3_RT_ALERT)
1779 * Only need to buffer if a handshake is underway. (this implies that
1780 * Hello Request and Client Hello are passed up immediately)
1782 if (SSL_in_init(s)) {
1783 unsigned char *data = rr->data;
1784 /* need to extract the HM/CCS sequence number here */
1785 if (rr->type == SSL3_RT_HANDSHAKE ||
1786 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1787 unsigned short seq_num;
1788 struct hm_header_st msg_hdr;
1789 struct ccs_header_st ccs_hdr;
1791 if (rr->type == SSL3_RT_HANDSHAKE) {
1792 dtls1_get_message_header(data, &msg_hdr);
1793 seq_num = msg_hdr.seq;
1794 *offset = msg_hdr.frag_off;
1796 dtls1_get_ccs_header(data, &ccs_hdr);
1797 seq_num = ccs_hdr.seq;
1802 * this is either a record we're waiting for, or a retransmit of
1803 * something we happened to previously receive (higher layers
1804 * will drop the repeat silently
1806 if (seq_num < s->d1->handshake_read_seq)
1808 if (rr->type == SSL3_RT_HANDSHAKE &&
1809 seq_num == s->d1->handshake_read_seq &&
1810 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1812 else if (seq_num == s->d1->handshake_read_seq &&
1813 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1814 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1817 *priority = seq_num;
1820 } else /* unknown record type */
1828 void dtls1_reset_seq_numbers(SSL *s, int rw)
1831 unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1833 if (rw & SSL3_CC_READ) {
1834 seq = s->s3->read_sequence;
1837 pq_64bit_assign(&(s->d1->bitmap.map), &(s->d1->next_bitmap.map));
1838 s->d1->bitmap.length = s->d1->next_bitmap.length;
1839 pq_64bit_assign(&(s->d1->bitmap.max_seq_num),
1840 &(s->d1->next_bitmap.max_seq_num));
1842 pq_64bit_free(&(s->d1->next_bitmap.map));
1843 pq_64bit_free(&(s->d1->next_bitmap.max_seq_num));
1844 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1845 pq_64bit_init(&(s->d1->next_bitmap.map));
1846 pq_64bit_init(&(s->d1->next_bitmap.max_seq_num));
1849 * We must not use any buffered messages received from the previous
1852 dtls1_clear_received_buffer(s);
1854 seq = s->s3->write_sequence;
1855 memcpy(s->d1->last_write_sequence, seq,
1856 sizeof(s->s3->write_sequence));
1860 memset(seq, 0x00, seq_bytes);
1863 #if PQ_64BIT_IS_INTEGER
1864 static PQ_64BIT bytes_to_long_long(unsigned char *bytes, PQ_64BIT * num)
1868 _num = (((PQ_64BIT) bytes[0]) << 56) |
1869 (((PQ_64BIT) bytes[1]) << 48) |
1870 (((PQ_64BIT) bytes[2]) << 40) |
1871 (((PQ_64BIT) bytes[3]) << 32) |
1872 (((PQ_64BIT) bytes[4]) << 24) |
1873 (((PQ_64BIT) bytes[5]) << 16) |
1874 (((PQ_64BIT) bytes[6]) << 8) | (((PQ_64BIT) bytes[7]));