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_2_VERSION 0xFEFD
88 #define DTLS_MAX_VERSION DTLS1_2_VERSION
90 #define DTLS1_BAD_VER 0x0100
92 /* Special value for method supporting multiple versions */
93 #define DTLS_ANY_VERSION 0x1FFFF
96 /* this alert description is not specified anywhere... */
97 #define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110
100 /* lengths of messages */
101 #define DTLS1_COOKIE_LENGTH 256
103 #define DTLS1_RT_HEADER_LENGTH 13
105 #define DTLS1_HM_HEADER_LENGTH 12
107 #define DTLS1_HM_BAD_FRAGMENT -2
108 #define DTLS1_HM_FRAGMENT_RETRY -3
110 #define DTLS1_CCS_HEADER_LENGTH 1
112 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
113 #define DTLS1_AL_HEADER_LENGTH 7
115 #define DTLS1_AL_HEADER_LENGTH 2
118 #ifndef OPENSSL_NO_SSL_INTERN
120 #ifndef OPENSSL_NO_SCTP
121 #define DTLS1_SCTP_AUTH_LABEL "EXPORTER_DTLS_OVER_SCTP"
124 /* Max MTU overhead we know about so far is 40 for IPv6 + 8 for UDP */
125 #define DTLS1_MAX_MTU_OVERHEAD 48
127 typedef struct dtls1_bitmap_st
129 unsigned long map; /* track 32 packets on 32-bit systems
130 and 64 - on 64-bit systems */
131 unsigned char max_seq_num[8]; /* max record number seen so far,
132 64-bit value in big-endian
136 struct dtls1_retransmit_state
138 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */
139 EVP_MD_CTX *write_hash; /* used for mac generation */
140 #ifndef OPENSSL_NO_COMP
141 COMP_CTX *compress; /* compression */
145 SSL_SESSION *session;
146 unsigned short epoch;
152 unsigned long msg_len;
154 unsigned long frag_off;
155 unsigned long frag_len;
157 struct dtls1_retransmit_state saved_retransmit_state;
166 struct dtls1_timeout_st
168 /* Number of read timeouts so far */
169 unsigned int read_timeouts;
171 /* Number of write timeouts so far */
172 unsigned int write_timeouts;
174 /* Number of alerts received so far */
175 unsigned int num_alerts;
178 typedef struct record_pqueue_st
180 unsigned short epoch;
184 typedef struct hm_fragment_st
186 struct hm_header_st msg_header;
187 unsigned char *fragment;
188 unsigned char *reassembly;
191 typedef struct dtls1_state_st
193 unsigned int send_cookie;
194 unsigned char cookie[DTLS1_COOKIE_LENGTH];
195 unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH];
196 unsigned int cookie_len;
199 * The current data and handshake epoch. This is initially
200 * undefined, and starts at zero once the initial handshake is
203 unsigned short r_epoch;
204 unsigned short w_epoch;
206 /* records being received in the current epoch */
209 /* renegotiation starts a new set of sequence numbers */
210 DTLS1_BITMAP next_bitmap;
212 /* handshake message numbers */
213 unsigned short handshake_write_seq;
214 unsigned short next_handshake_write_seq;
216 unsigned short handshake_read_seq;
218 /* save last sequence number for retransmissions */
219 unsigned char last_write_sequence[8];
221 /* Received handshake records (processed and unprocessed) */
222 record_pqueue unprocessed_rcds;
223 record_pqueue processed_rcds;
225 /* Buffered handshake messages */
226 pqueue buffered_messages;
228 /* Buffered (sent) handshake records */
229 pqueue sent_messages;
231 /* Buffered application records.
232 * Only for records between CCS and Finished
233 * to prevent either protocol violation or
234 * unnecessary message loss.
236 record_pqueue buffered_app_data;
238 /* Is set when listening for new connections with dtls1_listen() */
241 unsigned int link_mtu; /* max on-the-wire DTLS packet size */
242 unsigned int mtu; /* max DTLS packet size */
244 struct hm_header_st w_msg_hdr;
245 struct hm_header_st r_msg_hdr;
247 struct dtls1_timeout_st timeout;
249 /* Indicates when the last handshake msg or heartbeat sent will timeout */
250 struct timeval next_timeout;
252 /* Timeout duration */
253 unsigned short timeout_duration;
255 /* storage for Alert/Handshake protocol data received but not
256 * yet processed by ssl3_read_bytes: */
257 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH];
258 unsigned int alert_fragment_len;
259 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH];
260 unsigned int handshake_fragment_len;
262 unsigned int retransmitting;
264 * Set when the handshake is ready to process peer's ChangeCipherSpec message.
265 * Cleared after the message has been processed.
267 unsigned int change_cipher_spec_ok;
269 #ifndef OPENSSL_NO_SCTP
270 /* used when SSL_ST_XX_FLUSH is entered */
273 int shutdown_received;
278 typedef struct dtls1_record_data_st
280 unsigned char *packet;
281 unsigned int packet_length;
284 #ifndef OPENSSL_NO_SCTP
285 struct bio_dgram_sctp_rcvinfo recordinfo;
291 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
292 #define DTLS1_TMO_READ_COUNT 2
293 #define DTLS1_TMO_WRITE_COUNT 2
295 #define DTLS1_TMO_ALERT_COUNT 12