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
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>
86 #define DTLS1_VERSION 0xFEFF
87 #define DTLS1_BAD_VER 0x0100
88 #define DTLS1_2_VERSION 0xFEFD
91 /* this alert description is not specified anywhere... */
92 #define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110
95 /* lengths of messages */
96 #define DTLS1_COOKIE_LENGTH 256
98 #define DTLS1_RT_HEADER_LENGTH 13
100 #define DTLS1_HM_HEADER_LENGTH 12
102 #define DTLS1_HM_BAD_FRAGMENT -2
103 #define DTLS1_HM_FRAGMENT_RETRY -3
105 #define DTLS1_CCS_HEADER_LENGTH 1
107 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
108 #define DTLS1_AL_HEADER_LENGTH 7
110 #define DTLS1_AL_HEADER_LENGTH 2
113 #ifndef OPENSSL_NO_SSL_INTERN
115 #ifndef OPENSSL_NO_SCTP
116 #define DTLS1_SCTP_AUTH_LABEL "EXPORTER_DTLS_OVER_SCTP"
119 typedef struct dtls1_bitmap_st
121 unsigned long map; /* track 32 packets on 32-bit systems
122 and 64 - on 64-bit systems */
123 unsigned char max_seq_num[8]; /* max record number seen so far,
124 64-bit value in big-endian
128 struct dtls1_retransmit_state
130 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */
131 EVP_MD_CTX *write_hash; /* used for mac generation */
132 #ifndef OPENSSL_NO_COMP
133 COMP_CTX *compress; /* compression */
137 SSL_SESSION *session;
138 unsigned short epoch;
144 unsigned long msg_len;
146 unsigned long frag_off;
147 unsigned long frag_len;
149 struct dtls1_retransmit_state saved_retransmit_state;
158 struct dtls1_timeout_st
160 /* Number of read timeouts so far */
161 unsigned int read_timeouts;
163 /* Number of write timeouts so far */
164 unsigned int write_timeouts;
166 /* Number of alerts received so far */
167 unsigned int num_alerts;
170 typedef struct record_pqueue_st
172 unsigned short epoch;
176 typedef struct hm_fragment_st
178 struct hm_header_st msg_header;
179 unsigned char *fragment;
180 unsigned char *reassembly;
183 typedef struct dtls1_state_st
185 unsigned int send_cookie;
186 unsigned char cookie[DTLS1_COOKIE_LENGTH];
187 unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH];
188 unsigned int cookie_len;
191 * The current data and handshake epoch. This is initially
192 * undefined, and starts at zero once the initial handshake is
195 unsigned short r_epoch;
196 unsigned short w_epoch;
198 /* records being received in the current epoch */
201 /* renegotiation starts a new set of sequence numbers */
202 DTLS1_BITMAP next_bitmap;
204 /* handshake message numbers */
205 unsigned short handshake_write_seq;
206 unsigned short next_handshake_write_seq;
208 unsigned short handshake_read_seq;
210 /* save last sequence number for retransmissions */
211 unsigned char last_write_sequence[8];
213 /* Received handshake records (processed and unprocessed) */
214 record_pqueue unprocessed_rcds;
215 record_pqueue processed_rcds;
217 /* Buffered handshake messages */
218 pqueue buffered_messages;
220 /* Buffered (sent) handshake records */
221 pqueue sent_messages;
223 /* Buffered application records.
224 * Only for records between CCS and Finished
225 * to prevent either protocol violation or
226 * unnecessary message loss.
228 record_pqueue buffered_app_data;
230 /* Is set when listening for new connections with dtls1_listen() */
233 unsigned int mtu; /* max DTLS packet size */
235 struct hm_header_st w_msg_hdr;
236 struct hm_header_st r_msg_hdr;
238 struct dtls1_timeout_st timeout;
240 /* Indicates when the last handshake msg or heartbeat sent will timeout */
241 struct timeval next_timeout;
243 /* Timeout duration */
244 unsigned short timeout_duration;
246 /* storage for Alert/Handshake protocol data received but not
247 * yet processed by ssl3_read_bytes: */
248 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH];
249 unsigned int alert_fragment_len;
250 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH];
251 unsigned int handshake_fragment_len;
253 unsigned int retransmitting;
254 unsigned int change_cipher_spec_ok;
256 #ifndef OPENSSL_NO_SCTP
257 /* used when SSL_ST_XX_FLUSH is entered */
260 int shutdown_received;
265 typedef struct dtls1_record_data_st
267 unsigned char *packet;
268 unsigned int packet_length;
271 #ifndef OPENSSL_NO_SCTP
272 struct bio_dgram_sctp_rcvinfo recordinfo;
278 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
279 #define DTLS1_TMO_READ_COUNT 2
280 #define DTLS1_TMO_WRITE_COUNT 2
282 #define DTLS1_TMO_ALERT_COUNT 12