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). */
58 #ifndef HEADER_DTLS1_H
59 #define HEADER_DTLS1_H
61 #include <openssl/base.h>
62 #include <openssl/buf.h>
63 #include <openssl/pqueue.h>
70 #define DTLS1_VERSION 0xFEFF
71 #define DTLS1_2_VERSION 0xFEFD
72 /* Special value for method supporting multiple versions */
73 #define DTLS_ANY_VERSION 0x1FFFF
76 /* this alert description is not specified anywhere... */
77 #define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110
80 /* lengths of messages */
81 #define DTLS1_COOKIE_LENGTH 256
83 #define DTLS1_RT_HEADER_LENGTH 13
85 #define DTLS1_HM_HEADER_LENGTH 12
87 #define DTLS1_HM_BAD_FRAGMENT -2
88 #define DTLS1_HM_FRAGMENT_RETRY -3
90 #define DTLS1_CCS_HEADER_LENGTH 1
92 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
93 #define DTLS1_AL_HEADER_LENGTH 7
95 #define DTLS1_AL_HEADER_LENGTH 2
98 #ifndef OPENSSL_NO_SSL_INTERN
101 #if defined(OPENSSL_WINDOWS)
102 /* Because of Windows header issues, we can't get the normal declaration of
104 typedef struct OPENSSL_timeval_st {
109 #include <sys/time.h>
110 typedef struct timeval OPENSSL_timeval;
113 typedef struct dtls1_bitmap_st
115 unsigned long map; /* track 32 packets on 32-bit systems
116 and 64 - on 64-bit systems */
117 unsigned char max_seq_num[8]; /* max record number seen so far,
118 64-bit value in big-endian
122 struct dtls1_retransmit_state
124 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */
125 EVP_MD_CTX *write_hash; /* used for mac generation */
126 SSL_SESSION *session;
127 unsigned short epoch;
133 unsigned long msg_len;
135 unsigned long frag_off;
136 unsigned long frag_len;
138 struct dtls1_retransmit_state saved_retransmit_state;
147 struct dtls1_timeout_st
149 /* Number of read timeouts so far */
150 unsigned int read_timeouts;
152 /* Number of write timeouts so far */
153 unsigned int write_timeouts;
155 /* Number of alerts received so far */
156 unsigned int num_alerts;
159 typedef struct record_pqueue_st
161 unsigned short epoch;
165 typedef struct hm_fragment_st
167 struct hm_header_st msg_header;
168 unsigned char *fragment;
169 unsigned char *reassembly;
172 typedef struct dtls1_state_st
174 /* send_cookie is true if we are resending the ClientHello
175 * with a cookie from a HelloVerifyRequest. */
176 unsigned int send_cookie;
178 uint8_t cookie[DTLS1_COOKIE_LENGTH];
182 * The current data and handshake epoch. This is initially
183 * undefined, and starts at zero once the initial handshake is
186 unsigned short r_epoch;
187 unsigned short w_epoch;
189 /* records being received in the current epoch */
192 /* renegotiation starts a new set of sequence numbers */
193 DTLS1_BITMAP next_bitmap;
195 /* handshake message numbers */
196 unsigned short handshake_write_seq;
197 unsigned short next_handshake_write_seq;
199 unsigned short handshake_read_seq;
201 /* save last sequence number for retransmissions */
202 unsigned char last_write_sequence[8];
204 /* Received handshake records (processed and unprocessed) */
205 record_pqueue unprocessed_rcds;
206 record_pqueue processed_rcds;
208 /* Buffered handshake messages */
209 pqueue buffered_messages;
211 /* Buffered (sent) handshake records */
212 pqueue sent_messages;
214 /* Buffered application records.
215 * Only for records between CCS and Finished
216 * to prevent either protocol violation or
217 * unnecessary message loss.
219 record_pqueue buffered_app_data;
221 /* Is set when listening for new connections with dtls1_listen() */
224 unsigned int mtu; /* max DTLS packet size */
226 struct hm_header_st w_msg_hdr;
227 struct hm_header_st r_msg_hdr;
229 struct dtls1_timeout_st timeout;
231 /* Indicates when the last handshake msg or heartbeat sent will
232 * timeout. Because of header issues on Windows, this cannot actually
233 * be a struct timeval. */
234 OPENSSL_timeval next_timeout;
236 /* Timeout duration */
237 unsigned short timeout_duration;
239 /* storage for Alert/Handshake protocol data received but not
240 * yet processed by ssl3_read_bytes: */
241 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH];
242 unsigned int alert_fragment_len;
243 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH];
244 unsigned int handshake_fragment_len;
246 unsigned int retransmitting;
247 unsigned int change_cipher_spec_ok;
250 typedef struct dtls1_record_data_st
252 unsigned char *packet;
253 unsigned int packet_length;
260 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
261 #define DTLS1_TMO_READ_COUNT 2
262 #define DTLS1_TMO_WRITE_COUNT 2
264 #define DTLS1_TMO_ALERT_COUNT 12