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 /* mod 128 saturating subtract of two 64-bit values in big-endian order */
126 static int satsub64be(const unsigned char *v1,const unsigned char *v2)
129 if (sizeof(long) == 8) do
130 { const union { long one; char little; } is_endian = {1};
133 if (is_endian.little) break;
134 /* not reached on little-endians */
135 /* following test is redundant, because input is
136 * always aligned, but I take no chances... */
137 if (((size_t)v1|(size_t)v2)&0x7) break;
141 if (l>128) return 128;
142 else if (l<-128) return -128;
146 ret = (int)v1[7]-(int)v2[7];
148 brw = ret>>8; /* brw is either 0 or -1 */
151 { brw += (int)v1[i]-(int)v2[i];
158 { brw += (int)v1[i]-(int)v2[i];
163 brw <<= 8; /* brw is either 0 or -256 */
165 if (sat&0xff) return brw | 0x80;
166 else return brw + (ret&0xFF);
169 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
171 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
172 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
173 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
174 unsigned int *is_next_epoch);
176 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
177 unsigned short *priority, unsigned long *offset);
179 static int dtls1_buffer_record(SSL *s, record_pqueue *q,
180 unsigned char *priority);
181 static int dtls1_process_record(SSL *s);
183 /* copy buffered record into SSL structure */
185 dtls1_copy_record(SSL *s, pitem *item)
187 DTLS1_RECORD_DATA *rdata;
189 rdata = (DTLS1_RECORD_DATA *)item->data;
191 if (s->s3->rbuf.buf != NULL)
192 OPENSSL_free(s->s3->rbuf.buf);
194 s->packet = rdata->packet;
195 s->packet_length = rdata->packet_length;
196 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
197 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
199 /* Set proper sequence number for mac calculation */
200 memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6);
207 dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
209 DTLS1_RECORD_DATA *rdata;
212 /* Limit the size of the queue to prevent DOS attacks */
213 if (pqueue_size(queue->q) >= 100)
216 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
217 item = pitem_new(priority, rdata);
218 if (rdata == NULL || item == NULL)
220 if (rdata != NULL) OPENSSL_free(rdata);
221 if (item != NULL) pitem_free(item);
223 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
227 rdata->packet = s->packet;
228 rdata->packet_length = s->packet_length;
229 memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
230 memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
234 #ifndef OPENSSL_NO_SCTP
235 /* Store bio_dgram_sctp_rcvinfo struct */
236 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
237 (s->state == SSL3_ST_SR_FINISHED_A || s->state == SSL3_ST_CR_FINISHED_A)) {
238 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
243 s->packet_length = 0;
244 memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
245 memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
247 if (!ssl3_setup_buffers(s))
249 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
250 if (rdata->rbuf.buf != NULL)
251 OPENSSL_free(rdata->rbuf.buf);
257 /* insert should not fail, since duplicates are dropped */
258 if (pqueue_insert(queue->q, item) == NULL)
260 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
261 if (rdata->rbuf.buf != NULL)
262 OPENSSL_free(rdata->rbuf.buf);
273 dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
277 item = pqueue_pop(queue->q);
280 dtls1_copy_record(s, item);
282 OPENSSL_free(item->data);
292 /* retrieve a buffered record that belongs to the new epoch, i.e., not processed
294 #define dtls1_get_unprocessed_record(s) \
295 dtls1_retrieve_buffered_record((s), \
296 &((s)->d1->unprocessed_rcds))
298 /* retrieve a buffered record that belongs to the current epoch, ie, processed */
299 #define dtls1_get_processed_record(s) \
300 dtls1_retrieve_buffered_record((s), \
301 &((s)->d1->processed_rcds))
304 dtls1_process_buffered_records(SSL *s)
308 item = pqueue_peek(s->d1->unprocessed_rcds.q);
311 /* Check if epoch is current. */
312 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
313 return(1); /* Nothing to do. */
315 /* Process all the records. */
316 while (pqueue_peek(s->d1->unprocessed_rcds.q))
318 dtls1_get_unprocessed_record(s);
319 if ( ! dtls1_process_record(s))
321 if(dtls1_buffer_record(s, &(s->d1->processed_rcds),
322 s->s3->rrec.seq_num)<0)
327 /* sync epoch numbers once all the unprocessed records
328 * have been processed */
329 s->d1->processed_rcds.epoch = s->d1->r_epoch;
330 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
339 dtls1_get_buffered_record(SSL *s)
343 (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
344 ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
346 if ( ! SSL_in_init(s)) /* if we're not (re)negotiating,
351 item = pqueue_peek(s->d1->rcvd_records);
352 if (item && item->priority == priority)
354 /* Check if we've received the record of interest. It must be
355 * a handshake record, since data records as passed up without
357 DTLS1_RECORD_DATA *rdata;
358 item = pqueue_pop(s->d1->rcvd_records);
359 rdata = (DTLS1_RECORD_DATA *)item->data;
361 if (s->s3->rbuf.buf != NULL)
362 OPENSSL_free(s->s3->rbuf.buf);
364 s->packet = rdata->packet;
365 s->packet_length = rdata->packet_length;
366 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
367 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
369 OPENSSL_free(item->data);
372 /* s->d1->next_expected_seq_num++; */
382 dtls1_process_record(SSL *s)
388 unsigned int mac_size;
389 unsigned char md[EVP_MAX_MD_SIZE];
394 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
395 * and we have that many bytes in s->packet
397 rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
399 /* ok, we can now read from 's->packet' data into 'rr'
400 * rr->input points at rr->length bytes, which
401 * need to be copied into rr->data by either
402 * the decryption or by the decompression
403 * When the data is 'copied' into the rr->data buffer,
404 * rr->input will be pointed at the new buffer */
406 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
407 * rr->length bytes of encrypted compressed stuff. */
409 /* check is not needed I believe */
410 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
412 al=SSL_AD_RECORD_OVERFLOW;
413 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
417 /* decrypt in place in 'rr->input' */
419 rr->orig_len=rr->length;
421 enc_err = s->method->ssl3_enc->enc(s,0);
423 * 0: (in non-constant time) if the record is publically invalid.
424 * 1: if the padding is valid
425 * -1: if the padding is invalid */
428 /* For DTLS we simply ignore bad packets. */
430 s->packet_length = 0;
435 printf("dec %d\n",rr->length);
436 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
440 /* r->length is now the compressed data plus mac */
441 if ((sess != NULL) &&
442 (s->enc_read_ctx != NULL) &&
443 (EVP_MD_CTX_md(s->read_hash) != NULL))
445 /* s->read_hash != NULL => mac_size != -1 */
446 unsigned char *mac = NULL;
447 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
448 mac_size=EVP_MD_CTX_size(s->read_hash);
449 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
451 /* orig_len is the length of the record before any padding was
452 * removed. This is public information, as is the MAC in use,
453 * therefore we can safely process the record in a different
454 * amount of time if it's too short to possibly contain a MAC.
456 if (rr->orig_len < mac_size ||
457 /* CBC records must have a padding length byte too. */
458 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
459 rr->orig_len < mac_size+1))
461 al=SSL_AD_DECODE_ERROR;
462 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
466 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
468 /* We update the length so that the TLS header bytes
469 * can be constructed correctly but we need to extract
470 * the MAC in constant time from within the record,
471 * without leaking the contents of the padding bytes.
474 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);
475 rr->length -= mac_size;
479 /* In this case there's no padding, so |rec->orig_len|
480 * equals |rec->length| and we checked that there's
481 * enough bytes for |mac_size| above. */
482 rr->length -= mac_size;
483 mac = &rr->data[rr->length];
486 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
487 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
489 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
495 /* decryption failed, silently discard message */
497 s->packet_length = 0;
501 /* r->length is now just compressed */
502 if (s->expand != NULL)
504 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
506 al=SSL_AD_RECORD_OVERFLOW;
507 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
510 if (!ssl3_do_uncompress(s))
512 al=SSL_AD_DECOMPRESSION_FAILURE;
513 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
518 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
520 al=SSL_AD_RECORD_OVERFLOW;
521 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
527 * So at this point the following is true
528 * ssl->s3->rrec.type is the type of record
529 * ssl->s3->rrec.length == number of bytes in record
530 * ssl->s3->rrec.off == offset to first valid byte
531 * ssl->s3->rrec.data == where to take bytes from, increment
535 /* we have pulled in a full packet so zero things */
540 ssl3_send_alert(s,SSL3_AL_FATAL,al);
547 * Call this to get a new input record.
548 * It will return <= 0 if more data is needed, normally due to an error
549 * or non-blocking IO.
550 * When it finishes, one packet has been decoded and can be found in
551 * ssl->s3->rrec.type - is the type of record
552 * ssl->s3->rrec.data, - data
553 * ssl->s3->rrec.length, - number of bytes
555 /* used only by dtls1_read_bytes */
556 int dtls1_get_record(SSL *s)
558 int ssl_major,ssl_minor;
561 unsigned char *p = NULL;
562 unsigned short version;
563 DTLS1_BITMAP *bitmap;
564 unsigned int is_next_epoch;
568 /* The epoch may have changed. If so, process all the
569 * pending records. This is a non-blocking operation. */
570 if(dtls1_process_buffered_records(s)<0)
573 /* if we're renegotiating, then there may be buffered records */
574 if (dtls1_get_processed_record(s))
577 /* get something from the wire */
579 /* check if we have the header */
580 if ( (s->rstate != SSL_ST_READ_BODY) ||
581 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
583 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
584 /* read timeout is handled by dtls1_read_bytes */
585 if (n <= 0) return(n); /* error or non-blocking */
587 /* this packet contained a partial record, dump it */
588 if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
590 s->packet_length = 0;
594 s->rstate=SSL_ST_READ_BODY;
599 s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
601 /* Pull apart the header into the DTLS1_RECORD */
605 version=(ssl_major<<8)|ssl_minor;
607 /* sequence number is 64 bits, with top 2 bytes = epoch */
610 memcpy(&(s->s3->read_sequence[2]), p, 6);
615 /* Lets check version */
616 if (!s->first_packet)
618 if (version != s->version)
620 /* unexpected version, silently discard */
622 s->packet_length = 0;
627 if ((version & 0xff00) != (s->version & 0xff00))
629 /* wrong version, silently discard record */
631 s->packet_length = 0;
635 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
637 /* record too long, silently discard it */
639 s->packet_length = 0;
643 /* now s->rstate == SSL_ST_READ_BODY */
646 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
648 if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
650 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
652 n=ssl3_read_n(s,i,i,1);
653 /* this packet contained a partial record, dump it */
657 s->packet_length = 0;
661 /* now n == rr->length,
662 * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
664 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
666 /* match epochs. NULL means the packet is dropped on the floor */
667 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
671 s->packet_length = 0; /* dump this record */
672 goto again; /* get another record */
675 #ifndef OPENSSL_NO_SCTP
676 /* Only do replay check if no SCTP bio */
677 if (!BIO_dgram_is_sctp(SSL_get_rbio(s)))
680 /* Check whether this is a repeat, or aged record.
681 * Don't check if we're listening and this message is
682 * a ClientHello. They can look as if they're replayed,
683 * since they arrive from different connections and
684 * would be dropped unnecessarily.
686 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
687 s->packet_length > DTLS1_RT_HEADER_LENGTH &&
688 s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
689 !dtls1_record_replay_check(s, bitmap))
692 s->packet_length=0; /* dump this record */
693 goto again; /* get another record */
695 #ifndef OPENSSL_NO_SCTP
699 /* just read a 0 length packet */
700 if (rr->length == 0) goto again;
702 /* If this record is from the next epoch (either HM or ALERT),
703 * and a handshake is currently in progress, buffer it since it
704 * cannot be processed at this time. However, do not buffer
705 * anything while listening.
709 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen)
711 if(dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num)<0)
713 dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
716 s->packet_length = 0;
720 if (!dtls1_process_record(s))
723 s->packet_length = 0; /* dump this record */
724 goto again; /* get another record */
726 dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
733 * Return up to 'len' payload bytes received in 'type' records.
734 * 'type' is one of the following:
736 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
737 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
738 * - 0 (during a shutdown, no data has to be returned)
740 * If we don't have stored data to work from, read a SSL/TLS record first
741 * (possibly multiple records if we still don't have anything to return).
743 * This function must handle any surprises the peer may have for us, such as
744 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
745 * a surprise, but handled as if it were), or renegotiation requests.
746 * Also if record payloads contain fragments too small to process, we store
747 * them until there is enough for the respective protocol (the record protocol
748 * may use arbitrary fragmentation and even interleaving):
749 * Change cipher spec protocol
750 * just 1 byte needed, no need for keeping anything stored
752 * 2 bytes needed (AlertLevel, AlertDescription)
754 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
755 * to detect unexpected Client Hello and Hello Request messages
756 * here, anything else is handled by higher layers
757 * Application data protocol
758 * none of our business
760 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
765 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
767 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
768 if (!ssl3_setup_buffers(s))
771 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
772 (type != SSL3_RT_HANDSHAKE)) ||
773 (peek && (type != SSL3_RT_APPLICATION_DATA)))
775 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
779 /* check whether there's a handshake message (client hello?) waiting */
780 if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
783 /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
785 #ifndef OPENSSL_NO_SCTP
786 /* Continue handshake if it had to be interrupted to read
787 * app data with SCTP.
789 if ((!s->in_handshake && SSL_in_init(s)) ||
790 (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
791 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) &&
792 s->s3->in_read_app_data != 2))
794 if (!s->in_handshake && SSL_in_init(s))
797 /* type == SSL3_RT_APPLICATION_DATA */
798 i=s->handshake_func(s);
799 if (i < 0) return(i);
802 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
808 s->rwstate=SSL_NOTHING;
811 * s->s3->rrec.type - is the type of record
812 * s->s3->rrec.data, - data
813 * s->s3->rrec.off, - offset into 'data' for next read
814 * s->s3->rrec.length, - number of bytes.
818 /* We are not handshaking and have no data yet,
819 * so process data buffered during the last handshake
820 * in advance, if any.
822 if (s->state == SSL_ST_OK && rr->length == 0)
825 item = pqueue_pop(s->d1->buffered_app_data.q);
828 #ifndef OPENSSL_NO_SCTP
829 /* Restore bio_dgram_sctp_rcvinfo struct */
830 if (BIO_dgram_is_sctp(SSL_get_rbio(s)))
832 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *) item->data;
833 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
837 dtls1_copy_record(s, item);
839 OPENSSL_free(item->data);
844 /* Check for timeout */
845 if (dtls1_handle_timeout(s) > 0)
848 /* get new packet if necessary */
849 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
851 ret=dtls1_get_record(s);
854 ret = dtls1_read_failed(s, ret);
855 /* anything other than a timeout is an error */
863 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE)
869 /* we now have a packet which can be read and processed */
871 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
872 * reset by ssl3_get_finished */
873 && (rr->type != SSL3_RT_HANDSHAKE))
875 /* We now have application data between CCS and Finished.
876 * Most likely the packets were reordered on their way, so
877 * buffer the application data for later processing rather
878 * than dropping the connection.
880 if(dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num)<0)
882 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
889 /* If the other end has shut down, throw anything we read away
890 * (even in 'peek' mode) */
891 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
894 s->rwstate=SSL_NOTHING;
899 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
901 /* make sure that we are not getting application data when we
902 * are doing a handshake for the first time */
903 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
904 (s->enc_read_ctx == NULL))
906 al=SSL_AD_UNEXPECTED_MESSAGE;
907 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
911 if (len <= 0) return(len);
913 if ((unsigned int)len > rr->length)
916 n = (unsigned int)len;
918 memcpy(buf,&(rr->data[rr->off]),n);
925 s->rstate=SSL_ST_READ_HEADER;
930 #ifndef OPENSSL_NO_SCTP
931 /* We were about to renegotiate but had to read
932 * belated application data first, so retry.
934 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
935 rr->type == SSL3_RT_APPLICATION_DATA &&
936 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))
938 s->rwstate=SSL_READING;
939 BIO_clear_retry_flags(SSL_get_rbio(s));
940 BIO_set_retry_read(SSL_get_rbio(s));
943 /* We might had to delay a close_notify alert because
944 * of reordered app data. If there was an alert and there
945 * is no message to read anymore, finally set shutdown.
947 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
948 s->d1->shutdown_received && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
950 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
958 /* If we get here, then type != rr->type; if we have a handshake
959 * message, then it was unexpected (Hello Request or Client Hello). */
961 /* In case of record types for which we have 'fragment' storage,
962 * fill that so that we can process the data at a fixed place.
965 unsigned int k, dest_maxlen = 0;
966 unsigned char *dest = NULL;
967 unsigned int *dest_len = NULL;
969 if (rr->type == SSL3_RT_HANDSHAKE)
971 dest_maxlen = sizeof s->d1->handshake_fragment;
972 dest = s->d1->handshake_fragment;
973 dest_len = &s->d1->handshake_fragment_len;
975 else if (rr->type == SSL3_RT_ALERT)
977 dest_maxlen = sizeof(s->d1->alert_fragment);
978 dest = s->d1->alert_fragment;
979 dest_len = &s->d1->alert_fragment_len;
981 #ifndef OPENSSL_NO_HEARTBEATS
982 else if (rr->type == TLS1_RT_HEARTBEAT)
984 dtls1_process_heartbeat(s);
986 /* Exit and notify application to read again */
988 s->rwstate=SSL_READING;
989 BIO_clear_retry_flags(SSL_get_rbio(s));
990 BIO_set_retry_read(SSL_get_rbio(s));
994 /* else it's a CCS message, or application data or wrong */
995 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
997 /* Application data while renegotiating
998 * is allowed. Try again reading.
1000 if (rr->type == SSL3_RT_APPLICATION_DATA)
1003 s->s3->in_read_app_data=2;
1004 bio=SSL_get_rbio(s);
1005 s->rwstate=SSL_READING;
1006 BIO_clear_retry_flags(bio);
1007 BIO_set_retry_read(bio);
1011 /* Not certain if this is the right error handling */
1012 al=SSL_AD_UNEXPECTED_MESSAGE;
1013 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1017 if (dest_maxlen > 0)
1019 /* XDTLS: In a pathalogical case, the Client Hello
1020 * may be fragmented--don't always expect dest_maxlen bytes */
1021 if ( rr->length < dest_maxlen)
1023 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1025 * for normal alerts rr->length is 2, while
1026 * dest_maxlen is 7 if we were to handle this
1027 * non-existing alert...
1031 s->rstate=SSL_ST_READ_HEADER;
1036 /* now move 'n' bytes: */
1037 for ( k = 0; k < dest_maxlen; k++)
1039 dest[k] = rr->data[rr->off++];
1042 *dest_len = dest_maxlen;
1046 /* s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
1047 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
1048 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1050 /* If we are a client, check for an incoming 'Hello Request': */
1052 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1053 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1054 (s->session != NULL) && (s->session->cipher != NULL))
1056 s->d1->handshake_fragment_len = 0;
1058 if ((s->d1->handshake_fragment[1] != 0) ||
1059 (s->d1->handshake_fragment[2] != 0) ||
1060 (s->d1->handshake_fragment[3] != 0))
1062 al=SSL_AD_DECODE_ERROR;
1063 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1067 /* no need to check sequence number on HELLO REQUEST messages */
1069 if (s->msg_callback)
1070 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1071 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
1073 if (SSL_is_init_finished(s) &&
1074 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1075 !s->s3->renegotiate)
1077 s->d1->handshake_read_seq++;
1079 ssl3_renegotiate(s);
1080 if (ssl3_renegotiate_check(s))
1082 i=s->handshake_func(s);
1083 if (i < 0) return(i);
1086 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1090 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1092 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1095 /* In the case where we try to read application data,
1096 * but we trigger an SSL handshake, we return -1 with
1097 * the retry option set. Otherwise renegotiation may
1098 * cause nasty problems in the blocking world */
1099 s->rwstate=SSL_READING;
1100 bio=SSL_get_rbio(s);
1101 BIO_clear_retry_flags(bio);
1102 BIO_set_retry_read(bio);
1108 /* we either finished a handshake or ignored the request,
1109 * now try again to obtain the (application) data we were asked for */
1113 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
1115 int alert_level = s->d1->alert_fragment[0];
1116 int alert_descr = s->d1->alert_fragment[1];
1118 s->d1->alert_fragment_len = 0;
1120 if (s->msg_callback)
1121 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1122 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1124 if (s->info_callback != NULL)
1125 cb=s->info_callback;
1126 else if (s->ctx->info_callback != NULL)
1127 cb=s->ctx->info_callback;
1131 j = (alert_level << 8) | alert_descr;
1132 cb(s, SSL_CB_READ_ALERT, j);
1135 if (alert_level == 1) /* warning */
1137 s->s3->warn_alert = alert_descr;
1138 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1140 #ifndef OPENSSL_NO_SCTP
1141 /* With SCTP and streams the socket may deliver app data
1142 * after a close_notify alert. We have to check this
1143 * first so that nothing gets discarded.
1145 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1146 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
1148 s->d1->shutdown_received = 1;
1149 s->rwstate=SSL_READING;
1150 BIO_clear_retry_flags(SSL_get_rbio(s));
1151 BIO_set_retry_read(SSL_get_rbio(s));
1155 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1159 /* XXX: this is a possible improvement in the future */
1160 /* now check if it's a missing record */
1161 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1164 unsigned int frag_off;
1165 unsigned char *p = &(s->d1->alert_fragment[2]);
1170 dtls1_retransmit_message(s,
1171 dtls1_get_queue_priority(frag->msg_header.seq, 0),
1173 if ( ! found && SSL_in_init(s))
1175 /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
1176 /* requested a message not yet sent,
1177 send an alert ourselves */
1178 ssl3_send_alert(s,SSL3_AL_WARNING,
1179 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1184 else if (alert_level == 2) /* fatal */
1188 s->rwstate=SSL_NOTHING;
1189 s->s3->fatal_alert = alert_descr;
1190 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1191 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1192 ERR_add_error_data(2,"SSL alert number ",tmp);
1193 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1194 SSL_CTX_remove_session(s->ctx,s->session);
1199 al=SSL_AD_ILLEGAL_PARAMETER;
1200 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1207 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1209 s->rwstate=SSL_NOTHING;
1214 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1216 struct ccs_header_st ccs_hdr;
1217 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1219 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1221 if (s->version == DTLS1_BAD_VER)
1224 /* 'Change Cipher Spec' is just a single byte, so we know
1225 * exactly what the record payload has to look like */
1226 /* XDTLS: check that epoch is consistent */
1227 if ( (rr->length != ccs_hdr_len) ||
1228 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
1230 i=SSL_AD_ILLEGAL_PARAMETER;
1231 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1237 if (s->msg_callback)
1238 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1239 rr->data, 1, s, s->msg_callback_arg);
1241 /* We can't process a CCS now, because previous handshake
1242 * messages are still missing, so just drop it.
1244 if (!s->d1->change_cipher_spec_ok)
1249 s->d1->change_cipher_spec_ok = 0;
1251 s->s3->change_cipher_spec=1;
1252 if (!ssl3_do_change_cipher_spec(s))
1255 /* do this whenever CCS is processed */
1256 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1258 if (s->version == DTLS1_BAD_VER)
1259 s->d1->handshake_read_seq++;
1261 #ifndef OPENSSL_NO_SCTP
1262 /* Remember that a CCS has been received,
1263 * so that an old key of SCTP-Auth can be
1264 * deleted when a CCS is sent. Will be ignored
1265 * if no SCTP is used
1267 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
1273 /* Unexpected handshake message (Client Hello, or protocol violation) */
1274 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1277 struct hm_header_st msg_hdr;
1279 /* this may just be a stale retransmit */
1280 dtls1_get_message_header(rr->data, &msg_hdr);
1281 if( rr->epoch != s->d1->r_epoch)
1287 /* If we are server, we may have a repeated FINISHED of the
1288 * client here, then retransmit our CCS and FINISHED.
1290 if (msg_hdr.type == SSL3_MT_FINISHED)
1292 if (dtls1_check_timeout_num(s) < 0)
1295 dtls1_retransmit_buffered_messages(s);
1300 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1301 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1303 #if 0 /* worked only because C operator preferences are not as expected (and
1304 * because this is not really needed for clients except for detecting
1305 * protocol violations): */
1306 s->state=SSL_ST_BEFORE|(s->server)
1310 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1315 i=s->handshake_func(s);
1316 if (i < 0) return(i);
1319 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1323 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1325 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1328 /* In the case where we try to read application data,
1329 * but we trigger an SSL handshake, we return -1 with
1330 * the retry option set. Otherwise renegotiation may
1331 * cause nasty problems in the blocking world */
1332 s->rwstate=SSL_READING;
1333 bio=SSL_get_rbio(s);
1334 BIO_clear_retry_flags(bio);
1335 BIO_set_retry_read(bio);
1345 #ifndef OPENSSL_NO_TLS
1346 /* TLS just ignores unknown message types */
1347 if (s->version == TLS1_VERSION)
1353 al=SSL_AD_UNEXPECTED_MESSAGE;
1354 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1356 case SSL3_RT_CHANGE_CIPHER_SPEC:
1358 case SSL3_RT_HANDSHAKE:
1359 /* we already handled all of these, with the possible exception
1360 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1361 * should not happen when type != rr->type */
1362 al=SSL_AD_UNEXPECTED_MESSAGE;
1363 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1365 case SSL3_RT_APPLICATION_DATA:
1366 /* At this point, we were expecting handshake data,
1367 * but have application data. If the library was
1368 * running inside ssl3_read() (i.e. in_read_app_data
1369 * is set) and it makes sense to read application data
1370 * at this point (session renegotiation not yet started),
1371 * we will indulge it.
1373 if (s->s3->in_read_app_data &&
1374 (s->s3->total_renegotiations != 0) &&
1376 (s->state & SSL_ST_CONNECT) &&
1377 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1378 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1380 (s->state & SSL_ST_ACCEPT) &&
1381 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1382 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1386 s->s3->in_read_app_data=2;
1391 al=SSL_AD_UNEXPECTED_MESSAGE;
1392 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1399 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1405 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1409 #ifndef OPENSSL_NO_SCTP
1410 /* Check if we have to continue an interrupted handshake
1411 * for reading belated app data with SCTP.
1413 if ((SSL_in_init(s) && !s->in_handshake) ||
1414 (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
1415 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
1417 if (SSL_in_init(s) && !s->in_handshake)
1420 i=s->handshake_func(s);
1421 if (i < 0) return(i);
1424 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1429 if (len > SSL3_RT_MAX_PLAIN_LENGTH)
1431 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
1435 i = dtls1_write_bytes(s, type, buf_, len);
1440 /* this only happens when a client hello is received and a handshake
1443 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1447 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1448 /* (partially) satisfy request from storage */
1450 unsigned char *src = s->d1->handshake_fragment;
1451 unsigned char *dst = buf;
1456 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1459 len--; s->d1->handshake_fragment_len--;
1462 /* move any remaining fragment bytes: */
1463 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1464 s->d1->handshake_fragment[k] = *src++;
1474 /* Call this to write data in records of type 'type'
1475 * It will return <= 0 if not all data has been sent or non-blocking IO.
1477 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1481 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1482 s->rwstate=SSL_NOTHING;
1483 i=do_dtls1_write(s, type, buf, len, 0);
1487 int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1489 unsigned char *p,*pseq;
1490 int i,mac_size,clear=0;
1497 /* first check if there is a SSL3_BUFFER still being written
1498 * out. This will happen with non blocking IO */
1499 if (s->s3->wbuf.left != 0)
1501 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1502 return(ssl3_write_pending(s,type,buf,len));
1505 /* If we have an alert to send, lets send it */
1506 if (s->s3->alert_dispatch)
1508 i=s->method->ssl_dispatch_alert(s);
1511 /* if it went, fall through and send more stuff */
1514 if (len == 0 && !create_empty_fragment)
1521 if ( (sess == NULL) ||
1522 (s->enc_write_ctx == NULL) ||
1523 (EVP_MD_CTX_md(s->write_hash) == NULL))
1530 mac_size=EVP_MD_CTX_size(s->write_hash);
1535 /* DTLS implements explicit IV, so no need for empty fragments */
1537 /* 'create_empty_fragment' is true only when this function calls itself */
1538 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1539 && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1541 /* countermeasure against known-IV weakness in CBC ciphersuites
1542 * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1545 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1547 /* recursive function call with 'create_empty_fragment' set;
1548 * this prepares and buffers the data for an empty fragment
1549 * (these 'prefix_len' bytes are sent out later
1550 * together with the actual payload) */
1551 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1552 if (prefix_len <= 0)
1555 if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1557 /* insufficient space */
1558 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1563 s->s3->empty_fragment_done = 1;
1566 p = wb->buf + prefix_len;
1568 /* write the header */
1572 /* Special case: for hello verify request, client version 1.0 and
1573 * we haven't decided which version to use yet send back using
1574 * version 1.0 header: otherwise some clients will ignore it.
1576 if (s->method->version == DTLS_ANY_VERSION)
1578 *(p++)=DTLS1_VERSION>>8;
1579 *(p++)=DTLS1_VERSION&0xff;
1583 *(p++)=s->version>>8;
1584 *(p++)=s->version&0xff;
1587 /* field where we are to write out packet epoch, seq num and len */
1591 /* Explicit IV length, block ciphers appropriate version flag */
1592 if (s->enc_write_ctx)
1594 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1595 if (mode == EVP_CIPH_CBC_MODE)
1597 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1601 /* Need explicit part of IV for GCM mode */
1602 else if (mode == EVP_CIPH_GCM_MODE)
1603 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1610 /* lets setup the record stuff. */
1611 wr->data=p + eivlen; /* make room for IV in case of CBC */
1612 wr->length=(int)len;
1613 wr->input=(unsigned char *)buf;
1615 /* we now 'read' from wr->input, wr->length bytes into
1618 /* first we compress */
1619 if (s->compress != NULL)
1621 if (!ssl3_do_compress(s))
1623 SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1629 memcpy(wr->data,wr->input,wr->length);
1633 /* we should still have the output to wr->data and the input
1634 * from wr->input. Length should be wr->length.
1635 * wr->data still points in the wb->buf */
1639 if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1641 wr->length+=mac_size;
1644 /* this is true regardless of mac size */
1649 wr->length += eivlen;
1651 if(s->method->ssl3_enc->enc(s,1) < 1) goto err;
1653 /* record length after mac and block padding */
1654 /* if (type == SSL3_RT_APPLICATION_DATA ||
1655 (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1657 /* there's only one epoch between handshake and app data */
1659 s2n(s->d1->w_epoch, pseq);
1663 s2n(s->d1->handshake_epoch, pseq); */
1665 memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1667 s2n(wr->length,pseq);
1669 if (s->msg_callback)
1670 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1672 /* we should now have
1673 * wr->data pointing to the encrypted data, which is
1674 * wr->length long */
1675 wr->type=type; /* not needed but helps for debugging */
1676 wr->length+=DTLS1_RT_HEADER_LENGTH;
1678 #if 0 /* this is now done at the message layer */
1679 /* buffer the record, making it easy to handle retransmits */
1680 if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1681 dtls1_buffer_record(s, wr->data, wr->length,
1682 *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1685 ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1687 if (create_empty_fragment)
1689 /* we are in a recursive call;
1690 * just return the length, don't write out anything here
1695 /* now let's set up wb */
1696 wb->left = prefix_len + wr->length;
1699 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1700 s->s3->wpend_tot=len;
1701 s->s3->wpend_buf=buf;
1702 s->s3->wpend_type=type;
1703 s->s3->wpend_ret=len;
1705 /* we now just need to write the buffer */
1706 return ssl3_write_pending(s,type,buf,len);
1713 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1717 const unsigned char *seq = s->s3->read_sequence;
1719 cmp = satsub64be(seq,bitmap->max_seq_num);
1722 memcpy (s->s3->rrec.seq_num,seq,8);
1723 return 1; /* this record in new */
1726 if (shift >= sizeof(bitmap->map)*8)
1727 return 0; /* stale, outside the window */
1728 else if (bitmap->map & (1UL<<shift))
1729 return 0; /* record previously received */
1731 memcpy (s->s3->rrec.seq_num,seq,8);
1736 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1740 const unsigned char *seq = s->s3->read_sequence;
1742 cmp = satsub64be(seq,bitmap->max_seq_num);
1746 if (shift < sizeof(bitmap->map)*8)
1747 bitmap->map <<= shift, bitmap->map |= 1UL;
1750 memcpy(bitmap->max_seq_num,seq,8);
1754 if (shift < sizeof(bitmap->map)*8)
1755 bitmap->map |= 1UL<<shift;
1760 int dtls1_dispatch_alert(SSL *s)
1763 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1764 unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1765 unsigned char *ptr = &buf[0];
1767 s->s3->alert_dispatch=0;
1769 memset(buf, 0x00, sizeof(buf));
1770 *ptr++ = s->s3->send_alert[0];
1771 *ptr++ = s->s3->send_alert[1];
1773 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1774 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1776 s2n(s->d1->handshake_read_seq, ptr);
1778 if ( s->d1->r_msg_hdr.frag_off == 0) /* waiting for a new msg */
1781 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1785 fprintf(stderr, "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",s->d1->handshake_read_seq,s->d1->r_msg_hdr.seq);
1787 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1791 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1794 s->s3->alert_dispatch=1;
1795 /* fprintf( stderr, "not done with alert\n" ); */
1799 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1800 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1801 || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1804 (void)BIO_flush(s->wbio);
1806 if (s->msg_callback)
1807 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1808 2, s, s->msg_callback_arg);
1810 if (s->info_callback != NULL)
1811 cb=s->info_callback;
1812 else if (s->ctx->info_callback != NULL)
1813 cb=s->ctx->info_callback;
1817 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1818 cb(s,SSL_CB_WRITE_ALERT,j);
1825 static DTLS1_BITMAP *
1826 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1831 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1832 if (rr->epoch == s->d1->r_epoch)
1833 return &s->d1->bitmap;
1835 /* Only HM and ALERT messages can be from the next epoch */
1836 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1837 (rr->type == SSL3_RT_HANDSHAKE ||
1838 rr->type == SSL3_RT_ALERT))
1841 return &s->d1->next_bitmap;
1849 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1850 unsigned long *offset)
1853 /* alerts are passed up immediately */
1854 if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1855 rr->type == SSL3_RT_ALERT)
1858 /* Only need to buffer if a handshake is underway.
1859 * (this implies that Hello Request and Client Hello are passed up
1861 if ( SSL_in_init(s))
1863 unsigned char *data = rr->data;
1864 /* need to extract the HM/CCS sequence number here */
1865 if ( rr->type == SSL3_RT_HANDSHAKE ||
1866 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1868 unsigned short seq_num;
1869 struct hm_header_st msg_hdr;
1870 struct ccs_header_st ccs_hdr;
1872 if ( rr->type == SSL3_RT_HANDSHAKE)
1874 dtls1_get_message_header(data, &msg_hdr);
1875 seq_num = msg_hdr.seq;
1876 *offset = msg_hdr.frag_off;
1880 dtls1_get_ccs_header(data, &ccs_hdr);
1881 seq_num = ccs_hdr.seq;
1885 /* this is either a record we're waiting for, or a
1886 * retransmit of something we happened to previously
1887 * receive (higher layers will drop the repeat silently */
1888 if ( seq_num < s->d1->handshake_read_seq)
1890 if (rr->type == SSL3_RT_HANDSHAKE &&
1891 seq_num == s->d1->handshake_read_seq &&
1892 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1894 else if ( seq_num == s->d1->handshake_read_seq &&
1895 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1896 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1900 *priority = seq_num;
1904 else /* unknown record type */
1913 dtls1_reset_seq_numbers(SSL *s, int rw)
1916 unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1918 if ( rw & SSL3_CC_READ)
1920 seq = s->s3->read_sequence;
1922 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1923 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1927 seq = s->s3->write_sequence;
1928 memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
1932 memset(seq, 0x00, seq_bytes);