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 /* Unless _XOPEN_SOURCE_EXTENDED is defined, struct timeval will not be
64 properly defined with DEC C, at least on VMS */
65 #if defined(__DECC) || defined(__DECCXX)
66 #define _XOPEN_SOURCE_EXTENDED
69 #include <openssl/buffer.h>
70 #include <openssl/pqueue.h>
71 #ifdef OPENSSL_SYS_VMS
73 #include <sys/timeb.h>
75 #ifdef OPENSSL_SYS_WIN32
76 /* Needed for struct timeval */
78 #elif defined(OPENSSL_SYS_NETWARE) && !defined(_WINSOCK2API_)
79 #include <sys/timeval.h>
88 #define DTLS1_VERSION 0xFEFF
89 #define DTLS1_BAD_VER 0x0100
92 /* this alert description is not specified anywhere... */
93 #define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110
96 /* lengths of messages */
97 #define DTLS1_COOKIE_LENGTH 256
99 #define DTLS1_RT_HEADER_LENGTH 13
101 #define DTLS1_HM_HEADER_LENGTH 12
103 #define DTLS1_HM_BAD_FRAGMENT -2
104 #define DTLS1_HM_FRAGMENT_RETRY -3
106 #define DTLS1_CCS_HEADER_LENGTH 1
108 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
109 #define DTLS1_AL_HEADER_LENGTH 7
111 #define DTLS1_AL_HEADER_LENGTH 2
115 typedef struct dtls1_bitmap_st
117 unsigned long map; /* track 32 packets on 32-bit systems
118 and 64 - on 64-bit systems */
119 unsigned char max_seq_num[8]; /* max record number seen so far,
120 64-bit value in big-endian
124 struct dtls1_retransmit_state
126 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */
127 EVP_MD_CTX *write_hash; /* used for mac generation */
128 #ifndef OPENSSL_NO_COMP
129 COMP_CTX *compress; /* compression */
133 SSL_SESSION *session;
134 unsigned short epoch;
140 unsigned long msg_len;
142 unsigned long frag_off;
143 unsigned long frag_len;
145 struct dtls1_retransmit_state saved_retransmit_state;
154 struct dtls1_timeout_st
156 /* Number of read timeouts so far */
157 unsigned int read_timeouts;
159 /* Number of write timeouts so far */
160 unsigned int write_timeouts;
162 /* Number of alerts received so far */
163 unsigned int num_alerts;
166 typedef struct record_pqueue_st
168 unsigned short epoch;
172 typedef struct hm_fragment_st
174 struct hm_header_st msg_header;
175 unsigned char *fragment;
176 unsigned char *reassembly;
179 typedef struct dtls1_state_st
181 unsigned int send_cookie;
182 unsigned char cookie[DTLS1_COOKIE_LENGTH];
183 unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH];
184 unsigned int cookie_len;
187 * The current data and handshake epoch. This is initially
188 * undefined, and starts at zero once the initial handshake is
191 unsigned short r_epoch;
192 unsigned short w_epoch;
194 /* records being received in the current epoch */
197 /* renegotiation starts a new set of sequence numbers */
198 DTLS1_BITMAP next_bitmap;
200 /* handshake message numbers */
201 unsigned short handshake_write_seq;
202 unsigned short next_handshake_write_seq;
204 unsigned short handshake_read_seq;
206 /* save last sequence number for retransmissions */
207 unsigned char last_write_sequence[8];
209 /* Received handshake records (processed and unprocessed) */
210 record_pqueue unprocessed_rcds;
211 record_pqueue processed_rcds;
213 /* Buffered handshake messages */
214 pqueue buffered_messages;
216 /* Buffered (sent) handshake records */
217 pqueue sent_messages;
219 /* Buffered application records.
220 * Only for records between CCS and Finished
221 * to prevent either protocol violation or
222 * unnecessary message loss.
224 record_pqueue buffered_app_data;
226 /* Is set when listening for new connections with dtls1_listen() */
229 unsigned int mtu; /* max DTLS packet size */
231 struct hm_header_st w_msg_hdr;
232 struct hm_header_st r_msg_hdr;
234 struct dtls1_timeout_st timeout;
236 /* Indicates when the last handshake msg sent will timeout */
237 struct timeval next_timeout;
239 /* Timeout duration */
240 unsigned short timeout_duration;
242 /* storage for Alert/Handshake protocol data received but not
243 * yet processed by ssl3_read_bytes: */
244 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH];
245 unsigned int alert_fragment_len;
246 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH];
247 unsigned int handshake_fragment_len;
249 unsigned int retransmitting;
250 unsigned int change_cipher_spec_ok;
254 typedef struct dtls1_record_data_st
256 unsigned char *packet;
257 unsigned int packet_length;
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