dtls1.h revision 279264
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#if defined(OPENSSL_SYS_VXWORKS) 76#include <sys/times.h> 77#else 78#include <sys/time.h> 79#endif 80#endif 81 82#ifdef __cplusplus 83extern "C" { 84#endif 85 86#define DTLS1_VERSION 0xFEFF 87#define DTLS_MAX_VERSION DTLS1_VERSION 88 89#define DTLS1_BAD_VER 0x0100 90 91#if 0 92/* this alert description is not specified anywhere... */ 93#define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110 94#endif 95 96/* lengths of messages */ 97#define DTLS1_COOKIE_LENGTH 256 98 99#define DTLS1_RT_HEADER_LENGTH 13 100 101#define DTLS1_HM_HEADER_LENGTH 12 102 103#define DTLS1_HM_BAD_FRAGMENT -2 104#define DTLS1_HM_FRAGMENT_RETRY -3 105 106#define DTLS1_CCS_HEADER_LENGTH 1 107 108#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 109#define DTLS1_AL_HEADER_LENGTH 7 110#else 111#define DTLS1_AL_HEADER_LENGTH 2 112#endif 113 114#ifndef OPENSSL_NO_SSL_INTERN 115 116#ifndef OPENSSL_NO_SCTP 117#define DTLS1_SCTP_AUTH_LABEL "EXPORTER_DTLS_OVER_SCTP" 118#endif 119 120/* Max MTU overhead we know about so far is 40 for IPv6 + 8 for UDP */ 121#define DTLS1_MAX_MTU_OVERHEAD 48 122 123typedef struct dtls1_bitmap_st 124 { 125 unsigned long map; /* track 32 packets on 32-bit systems 126 and 64 - on 64-bit systems */ 127 unsigned char max_seq_num[8]; /* max record number seen so far, 128 64-bit value in big-endian 129 encoding */ 130 } DTLS1_BITMAP; 131 132struct dtls1_retransmit_state 133 { 134 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */ 135 EVP_MD_CTX *write_hash; /* used for mac generation */ 136#ifndef OPENSSL_NO_COMP 137 COMP_CTX *compress; /* compression */ 138#else 139 char *compress; 140#endif 141 SSL_SESSION *session; 142 unsigned short epoch; 143 }; 144 145struct hm_header_st 146 { 147 unsigned char type; 148 unsigned long msg_len; 149 unsigned short seq; 150 unsigned long frag_off; 151 unsigned long frag_len; 152 unsigned int is_ccs; 153 struct dtls1_retransmit_state saved_retransmit_state; 154 }; 155 156struct ccs_header_st 157 { 158 unsigned char type; 159 unsigned short seq; 160 }; 161 162struct dtls1_timeout_st 163 { 164 /* Number of read timeouts so far */ 165 unsigned int read_timeouts; 166 167 /* Number of write timeouts so far */ 168 unsigned int write_timeouts; 169 170 /* Number of alerts received so far */ 171 unsigned int num_alerts; 172 }; 173 174typedef struct record_pqueue_st 175 { 176 unsigned short epoch; 177 pqueue q; 178 } record_pqueue; 179 180typedef struct hm_fragment_st 181 { 182 struct hm_header_st msg_header; 183 unsigned char *fragment; 184 unsigned char *reassembly; 185 } hm_fragment; 186 187typedef struct dtls1_state_st 188 { 189 unsigned int send_cookie; 190 unsigned char cookie[DTLS1_COOKIE_LENGTH]; 191 unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH]; 192 unsigned int cookie_len; 193 194 /* 195 * The current data and handshake epoch. This is initially 196 * undefined, and starts at zero once the initial handshake is 197 * completed 198 */ 199 unsigned short r_epoch; 200 unsigned short w_epoch; 201 202 /* records being received in the current epoch */ 203 DTLS1_BITMAP bitmap; 204 205 /* renegotiation starts a new set of sequence numbers */ 206 DTLS1_BITMAP next_bitmap; 207 208 /* handshake message numbers */ 209 unsigned short handshake_write_seq; 210 unsigned short next_handshake_write_seq; 211 212 unsigned short handshake_read_seq; 213 214 /* save last sequence number for retransmissions */ 215 unsigned char last_write_sequence[8]; 216 217 /* Received handshake records (processed and unprocessed) */ 218 record_pqueue unprocessed_rcds; 219 record_pqueue processed_rcds; 220 221 /* Buffered handshake messages */ 222 pqueue buffered_messages; 223 224 /* Buffered (sent) handshake records */ 225 pqueue sent_messages; 226 227 /* Buffered application records. 228 * Only for records between CCS and Finished 229 * to prevent either protocol violation or 230 * unnecessary message loss. 231 */ 232 record_pqueue buffered_app_data; 233 234 /* Is set when listening for new connections with dtls1_listen() */ 235 unsigned int listen; 236 237 unsigned int link_mtu; /* max on-the-wire DTLS packet size */ 238 unsigned int mtu; /* max DTLS packet size */ 239 240 struct hm_header_st w_msg_hdr; 241 struct hm_header_st r_msg_hdr; 242 243 struct dtls1_timeout_st timeout; 244 245 /* Indicates when the last handshake msg or heartbeat sent will timeout */ 246 struct timeval next_timeout; 247 248 /* Timeout duration */ 249 unsigned short timeout_duration; 250 251 /* storage for Alert/Handshake protocol data received but not 252 * yet processed by ssl3_read_bytes: */ 253 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH]; 254 unsigned int alert_fragment_len; 255 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH]; 256 unsigned int handshake_fragment_len; 257 258 unsigned int retransmitting; 259 /* 260 * Set when the handshake is ready to process peer's ChangeCipherSpec message. 261 * Cleared after the message has been processed. 262 */ 263 unsigned int change_cipher_spec_ok; 264 265#ifndef OPENSSL_NO_SCTP 266 /* used when SSL_ST_XX_FLUSH is entered */ 267 int next_state; 268 269 int shutdown_received; 270#endif 271 272 } DTLS1_STATE; 273 274typedef struct dtls1_record_data_st 275 { 276 unsigned char *packet; 277 unsigned int packet_length; 278 SSL3_BUFFER rbuf; 279 SSL3_RECORD rrec; 280#ifndef OPENSSL_NO_SCTP 281 struct bio_dgram_sctp_rcvinfo recordinfo; 282#endif 283 } DTLS1_RECORD_DATA; 284 285#endif 286 287/* Timeout multipliers (timeout slice is defined in apps/timeouts.h */ 288#define DTLS1_TMO_READ_COUNT 2 289#define DTLS1_TMO_WRITE_COUNT 2 290 291#define DTLS1_TMO_ALERT_COUNT 12 292 293#ifdef __cplusplus 294} 295#endif 296#endif 297