3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
6 /* ====================================================================
7 * Copyright (c) 1999-2005 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).
60 #ifndef HEADER_DTLS1_H
61 # define HEADER_DTLS1_H
63 # include <openssl/buffer.h>
64 # include <openssl/pqueue.h>
65 # ifdef OPENSSL_SYS_VMS
66 # include <resource.h>
67 # include <sys/timeb.h>
69 # ifdef OPENSSL_SYS_WIN32
70 /* Needed for struct timeval */
72 # elif defined(OPENSSL_SYS_NETWARE) && !defined(_WINSOCK2API_)
73 # include <sys/timeval.h>
75 # if defined(OPENSSL_SYS_VXWORKS)
76 # include <sys/times.h>
78 # include <sys/time.h>
86 # define DTLS1_VERSION 0xFEFF
87 # define DTLS_MAX_VERSION DTLS1_VERSION
88 # define DTLS1_VERSION_MAJOR 0xFE
90 # define DTLS1_BAD_VER 0x0100
93 /* this alert description is not specified anywhere... */
94 # define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110
97 /* lengths of messages */
98 # define DTLS1_COOKIE_LENGTH 256
100 # define DTLS1_RT_HEADER_LENGTH 13
102 # define DTLS1_HM_HEADER_LENGTH 12
104 # define DTLS1_HM_BAD_FRAGMENT -2
105 # define DTLS1_HM_FRAGMENT_RETRY -3
107 # define DTLS1_CCS_HEADER_LENGTH 1
109 # ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
110 # define DTLS1_AL_HEADER_LENGTH 7
112 # define DTLS1_AL_HEADER_LENGTH 2
115 # ifndef OPENSSL_NO_SSL_INTERN
117 # ifndef OPENSSL_NO_SCTP
118 # define DTLS1_SCTP_AUTH_LABEL "EXPORTER_DTLS_OVER_SCTP"
121 /* Max MTU overhead we know about so far is 40 for IPv6 + 8 for UDP */
122 # define DTLS1_MAX_MTU_OVERHEAD 48
124 typedef struct dtls1_bitmap_st
{
125 unsigned long map
; /* track 32 packets on 32-bit systems and 64
126 * - on 64-bit systems */
127 unsigned char max_seq_num
[8]; /* max record number seen so far, 64-bit
128 * value in big-endian encoding */
131 struct dtls1_retransmit_state
{
132 EVP_CIPHER_CTX
*enc_write_ctx
; /* cryptographic state */
133 EVP_MD_CTX
*write_hash
; /* used for mac generation */
134 # ifndef OPENSSL_NO_COMP
135 COMP_CTX
*compress
; /* compression */
139 SSL_SESSION
*session
;
140 unsigned short epoch
;
143 struct hm_header_st
{
145 unsigned long msg_len
;
147 unsigned long frag_off
;
148 unsigned long frag_len
;
150 struct dtls1_retransmit_state saved_retransmit_state
;
153 struct ccs_header_st
{
158 struct dtls1_timeout_st
{
159 /* Number of read timeouts so far */
160 unsigned int read_timeouts
;
161 /* Number of write timeouts so far */
162 unsigned int write_timeouts
;
163 /* Number of alerts received so far */
164 unsigned int num_alerts
;
167 typedef struct record_pqueue_st
{
168 unsigned short epoch
;
172 typedef struct hm_fragment_st
{
173 struct hm_header_st msg_header
;
174 unsigned char *fragment
;
175 unsigned char *reassembly
;
178 typedef struct dtls1_state_st
{
179 unsigned int send_cookie
;
180 unsigned char cookie
[DTLS1_COOKIE_LENGTH
];
181 unsigned char rcvd_cookie
[DTLS1_COOKIE_LENGTH
];
182 unsigned int cookie_len
;
184 * The current data and handshake epoch. This is initially
185 * undefined, and starts at zero once the initial handshake is
188 unsigned short r_epoch
;
189 unsigned short w_epoch
;
190 /* records being received in the current epoch */
192 /* renegotiation starts a new set of sequence numbers */
193 DTLS1_BITMAP next_bitmap
;
194 /* handshake message numbers */
195 unsigned short handshake_write_seq
;
196 unsigned short next_handshake_write_seq
;
197 unsigned short handshake_read_seq
;
198 /* save last sequence number for retransmissions */
199 unsigned char last_write_sequence
[8];
200 /* Received handshake records (processed and unprocessed) */
201 record_pqueue unprocessed_rcds
;
202 record_pqueue processed_rcds
;
203 /* Buffered handshake messages */
204 pqueue buffered_messages
;
205 /* Buffered (sent) handshake records */
206 pqueue sent_messages
;
208 * Buffered application records. Only for records between CCS and
209 * Finished to prevent either protocol violation or unnecessary message
212 record_pqueue buffered_app_data
;
213 /* Is set when listening for new connections with dtls1_listen() */
215 unsigned int link_mtu
; /* max on-the-wire DTLS packet size */
216 unsigned int mtu
; /* max DTLS packet size */
217 struct hm_header_st w_msg_hdr
;
218 struct hm_header_st r_msg_hdr
;
219 struct dtls1_timeout_st timeout
;
221 * Indicates when the last handshake msg or heartbeat sent will timeout
223 struct timeval next_timeout
;
224 /* Timeout duration */
225 unsigned short timeout_duration
;
227 * storage for Alert/Handshake protocol data received but not yet
228 * processed by ssl3_read_bytes:
230 unsigned char alert_fragment
[DTLS1_AL_HEADER_LENGTH
];
231 unsigned int alert_fragment_len
;
232 unsigned char handshake_fragment
[DTLS1_HM_HEADER_LENGTH
];
233 unsigned int handshake_fragment_len
;
234 unsigned int retransmitting
;
236 * Set when the handshake is ready to process peer's ChangeCipherSpec message.
237 * Cleared after the message has been processed.
239 unsigned int change_cipher_spec_ok
;
240 # ifndef OPENSSL_NO_SCTP
241 /* used when SSL_ST_XX_FLUSH is entered */
243 int shutdown_received
;
247 typedef struct dtls1_record_data_st
{
248 unsigned char *packet
;
249 unsigned int packet_length
;
252 # ifndef OPENSSL_NO_SCTP
253 struct bio_dgram_sctp_rcvinfo recordinfo
;
259 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
260 # define DTLS1_TMO_READ_COUNT 2
261 # define DTLS1_TMO_WRITE_COUNT 2
263 # define DTLS1_TMO_ALERT_COUNT 12