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 DTLS1_2_VERSION 0xFEFD
88 # define DTLS_MAX_VERSION DTLS1_2_VERSION
89 # define DTLS1_VERSION_MAJOR 0xFE
91 # define DTLS1_BAD_VER 0x0100
93 /* Special value for method supporting multiple versions */
94 # define DTLS_ANY_VERSION 0x1FFFF
97 /* this alert description is not specified anywhere... */
98 # define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110
101 /* lengths of messages */
102 # define DTLS1_COOKIE_LENGTH 256
104 # define DTLS1_RT_HEADER_LENGTH 13
106 # define DTLS1_HM_HEADER_LENGTH 12
108 # define DTLS1_HM_BAD_FRAGMENT -2
109 # define DTLS1_HM_FRAGMENT_RETRY -3
111 # define DTLS1_CCS_HEADER_LENGTH 1
113 # ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
114 # define DTLS1_AL_HEADER_LENGTH 7
116 # define DTLS1_AL_HEADER_LENGTH 2
119 # ifndef OPENSSL_NO_SSL_INTERN
121 # ifndef OPENSSL_NO_SCTP
122 # define DTLS1_SCTP_AUTH_LABEL "EXPORTER_DTLS_OVER_SCTP"
125 /* Max MTU overhead we know about so far is 40 for IPv6 + 8 for UDP */
126 # define DTLS1_MAX_MTU_OVERHEAD 48
128 typedef struct dtls1_bitmap_st
{
129 unsigned long map
; /* track 32 packets on 32-bit systems and 64
130 * - on 64-bit systems */
131 unsigned char max_seq_num
[8]; /* max record number seen so far, 64-bit
132 * value in big-endian encoding */
135 struct dtls1_retransmit_state
{
136 EVP_CIPHER_CTX
*enc_write_ctx
; /* cryptographic state */
137 EVP_MD_CTX
*write_hash
; /* used for mac generation */
138 # ifndef OPENSSL_NO_COMP
139 COMP_CTX
*compress
; /* compression */
143 SSL_SESSION
*session
;
144 unsigned short epoch
;
147 struct hm_header_st
{
149 unsigned long msg_len
;
151 unsigned long frag_off
;
152 unsigned long frag_len
;
154 struct dtls1_retransmit_state saved_retransmit_state
;
157 struct ccs_header_st
{
162 struct dtls1_timeout_st
{
163 /* Number of read timeouts so far */
164 unsigned int read_timeouts
;
165 /* Number of write timeouts so far */
166 unsigned int write_timeouts
;
167 /* Number of alerts received so far */
168 unsigned int num_alerts
;
171 typedef struct record_pqueue_st
{
172 unsigned short epoch
;
176 typedef struct hm_fragment_st
{
177 struct hm_header_st msg_header
;
178 unsigned char *fragment
;
179 unsigned char *reassembly
;
182 typedef struct dtls1_state_st
{
183 unsigned int send_cookie
;
184 unsigned char cookie
[DTLS1_COOKIE_LENGTH
];
185 unsigned char rcvd_cookie
[DTLS1_COOKIE_LENGTH
];
186 unsigned int cookie_len
;
188 * The current data and handshake epoch. This is initially
189 * undefined, and starts at zero once the initial handshake is
192 unsigned short r_epoch
;
193 unsigned short w_epoch
;
194 /* records being received in the current epoch */
196 /* renegotiation starts a new set of sequence numbers */
197 DTLS1_BITMAP next_bitmap
;
198 /* handshake message numbers */
199 unsigned short handshake_write_seq
;
200 unsigned short next_handshake_write_seq
;
201 unsigned short handshake_read_seq
;
202 /* save last sequence number for retransmissions */
203 unsigned char last_write_sequence
[8];
204 /* Received handshake records (processed and unprocessed) */
205 record_pqueue unprocessed_rcds
;
206 record_pqueue processed_rcds
;
207 /* Buffered handshake messages */
208 pqueue buffered_messages
;
209 /* Buffered (sent) handshake records */
210 pqueue sent_messages
;
212 * Buffered application records. Only for records between CCS and
213 * Finished to prevent either protocol violation or unnecessary message
216 record_pqueue buffered_app_data
;
217 /* Is set when listening for new connections with dtls1_listen() */
219 unsigned int link_mtu
; /* max on-the-wire DTLS packet size */
220 unsigned int mtu
; /* max DTLS packet size */
221 struct hm_header_st w_msg_hdr
;
222 struct hm_header_st r_msg_hdr
;
223 struct dtls1_timeout_st timeout
;
225 * Indicates when the last handshake msg or heartbeat sent will timeout
227 struct timeval next_timeout
;
228 /* Timeout duration */
229 unsigned short timeout_duration
;
231 * storage for Alert/Handshake protocol data received but not yet
232 * processed by ssl3_read_bytes:
234 unsigned char alert_fragment
[DTLS1_AL_HEADER_LENGTH
];
235 unsigned int alert_fragment_len
;
236 unsigned char handshake_fragment
[DTLS1_HM_HEADER_LENGTH
];
237 unsigned int handshake_fragment_len
;
238 unsigned int retransmitting
;
240 * Set when the handshake is ready to process peer's ChangeCipherSpec message.
241 * Cleared after the message has been processed.
243 unsigned int change_cipher_spec_ok
;
244 # ifndef OPENSSL_NO_SCTP
245 /* used when SSL_ST_XX_FLUSH is entered */
247 int shutdown_received
;
251 typedef struct dtls1_record_data_st
{
252 unsigned char *packet
;
253 unsigned int packet_length
;
256 # ifndef OPENSSL_NO_SCTP
257 struct bio_dgram_sctp_rcvinfo recordinfo
;
263 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
264 # define DTLS1_TMO_READ_COUNT 2
265 # define DTLS1_TMO_WRITE_COUNT 2
267 # define DTLS1_TMO_ALERT_COUNT 12