dtls1.h revision 273415
1/* ssl/dtls1.h */
2/*
3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
5 */
6/* ====================================================================
7 * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 *
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
19 *    distribution.
20 *
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/)"
25 *
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.
30 *
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.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 *    acknowledgment:
37 *    "This product includes software developed by the OpenSSL Project
38 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 *
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 * ====================================================================
53 *
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).
57 *
58 */
59
60#ifndef HEADER_DTLS1_H
61#define HEADER_DTLS1_H
62
63#include <openssl/buffer.h>
64#include <openssl/pqueue.h>
65#ifdef OPENSSL_SYS_VMS
66#include <resource.h>
67#include <sys/timeb.h>
68#endif
69#ifdef OPENSSL_SYS_WIN32
70/* Needed for struct timeval */
71#include <winsock.h>
72#elif defined(OPENSSL_SYS_NETWARE) && !defined(_WINSOCK2API_)
73#include <sys/timeval.h>
74#else
75#include <sys/time.h>
76#endif
77
78#ifdef  __cplusplus
79extern "C" {
80#endif
81
82#define DTLS1_VERSION			0xFEFF
83#define DTLS_MAX_VERSION		DTLS1_VERSION
84
85#define DTLS1_BAD_VER			0x0100
86
87#if 0
88/* this alert description is not specified anywhere... */
89#define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE    110
90#endif
91
92/* lengths of messages */
93#define DTLS1_COOKIE_LENGTH                     256
94
95#define DTLS1_RT_HEADER_LENGTH                  13
96
97#define DTLS1_HM_HEADER_LENGTH                  12
98
99#define DTLS1_HM_BAD_FRAGMENT                   -2
100#define DTLS1_HM_FRAGMENT_RETRY                 -3
101
102#define DTLS1_CCS_HEADER_LENGTH                  1
103
104#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
105#define DTLS1_AL_HEADER_LENGTH                   7
106#else
107#define DTLS1_AL_HEADER_LENGTH                   2
108#endif
109
110
111typedef struct dtls1_bitmap_st
112	{
113	PQ_64BIT map;
114	unsigned long length;     /* sizeof the bitmap in bits */
115	PQ_64BIT max_seq_num;  /* max record number seen so far */
116	} DTLS1_BITMAP;
117
118struct dtls1_retransmit_state
119	{
120	EVP_CIPHER_CTX *enc_write_ctx;	/* cryptographic state */
121	const EVP_MD *write_hash;		/* used for mac generation */
122#ifndef OPENSSL_NO_COMP
123	COMP_CTX *compress;				/* compression */
124#else
125	char *compress;
126#endif
127	SSL_SESSION *session;
128	unsigned short epoch;
129	};
130
131struct hm_header_st
132	{
133	unsigned char type;
134	unsigned long msg_len;
135	unsigned short seq;
136	unsigned long frag_off;
137	unsigned long frag_len;
138	unsigned int is_ccs;
139	struct dtls1_retransmit_state saved_retransmit_state;
140	};
141
142struct ccs_header_st
143	{
144	unsigned char type;
145	unsigned short seq;
146	};
147
148struct dtls1_timeout_st
149	{
150	/* Number of read timeouts so far */
151	unsigned int read_timeouts;
152
153	/* Number of write timeouts so far */
154	unsigned int write_timeouts;
155
156	/* Number of alerts received so far */
157	unsigned int num_alerts;
158	};
159
160typedef struct record_pqueue_st
161	{
162	unsigned short epoch;
163	pqueue q;
164	} record_pqueue;
165
166typedef struct hm_fragment_st
167	{
168	struct hm_header_st msg_header;
169	unsigned char *fragment;
170	unsigned char *reassembly;
171	} hm_fragment;
172
173typedef struct dtls1_state_st
174	{
175	unsigned int send_cookie;
176	unsigned char cookie[DTLS1_COOKIE_LENGTH];
177	unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH];
178	unsigned int cookie_len;
179
180	/*
181	 * The current data and handshake epoch.  This is initially
182	 * undefined, and starts at zero once the initial handshake is
183	 * completed
184	 */
185	unsigned short r_epoch;
186	unsigned short w_epoch;
187
188	/* records being received in the current epoch */
189	DTLS1_BITMAP bitmap;
190
191	/* renegotiation starts a new set of sequence numbers */
192	DTLS1_BITMAP next_bitmap;
193
194	/* handshake message numbers */
195	unsigned short handshake_write_seq;
196	unsigned short next_handshake_write_seq;
197
198	unsigned short handshake_read_seq;
199
200	/* save last sequence number for retransmissions */
201	unsigned char last_write_sequence[8];
202
203	/* Received handshake records (processed and unprocessed) */
204	record_pqueue unprocessed_rcds;
205	record_pqueue processed_rcds;
206
207	/* Buffered handshake messages */
208	pqueue buffered_messages;
209
210	/* Buffered (sent) handshake records */
211	pqueue sent_messages;
212
213	/* Buffered application records.
214	 * Only for records between CCS and Finished
215	 * to prevent either protocol violation or
216	 * unnecessary message loss.
217	 */
218	record_pqueue buffered_app_data;
219
220	/* Is set when listening for new connections with dtls1_listen() */
221	unsigned int listen;
222
223	unsigned int mtu; /* max DTLS packet size */
224
225	struct hm_header_st w_msg_hdr;
226	struct hm_header_st r_msg_hdr;
227
228	struct dtls1_timeout_st timeout;
229
230	/* Indicates when the last handshake msg sent will timeout */
231	struct timeval next_timeout;
232
233	/* Timeout duration */
234	unsigned short timeout_duration;
235
236	/* storage for Alert/Handshake protocol data received but not
237	 * yet processed by ssl3_read_bytes: */
238	unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH];
239	unsigned int alert_fragment_len;
240	unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH];
241	unsigned int handshake_fragment_len;
242
243	unsigned int retransmitting;
244	unsigned int change_cipher_spec_ok;
245
246	} DTLS1_STATE;
247
248typedef struct dtls1_record_data_st
249	{
250	unsigned char *packet;
251	unsigned int   packet_length;
252	SSL3_BUFFER    rbuf;
253	SSL3_RECORD    rrec;
254	} DTLS1_RECORD_DATA;
255
256
257/* Timeout multipliers (timeout slice is defined in apps/timeouts.h */
258#define DTLS1_TMO_READ_COUNT                      2
259#define DTLS1_TMO_WRITE_COUNT                     2
260
261#define DTLS1_TMO_ALERT_COUNT                     12
262
263#ifdef  __cplusplus
264}
265#endif
266#endif
267