1 /* ssl/dtls1.h */ 2 /* 3 * DTLS implementation written by Nagendra Modadugu 4 * (nagendra (at) 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 (at) 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 (at) cryptsoft.com). This product includes software written by Tim 56 * Hudson (tjh (at) 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 83 extern "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 typedef struct dtls1_bitmap_st 121 { 122 unsigned long map; /* track 32 packets on 32-bit systems 123 and 64 - on 64-bit systems */ 124 unsigned char max_seq_num[8]; /* max record number seen so far, 125 64-bit value in big-endian 126 encoding */ 127 } DTLS1_BITMAP; 128 129 struct dtls1_retransmit_state 130 { 131 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */ 132 EVP_MD_CTX *write_hash; /* used for mac generation */ 133 #ifndef OPENSSL_NO_COMP 134 COMP_CTX *compress; /* compression */ 135 #else 136 char *compress; 137 #endif 138 SSL_SESSION *session; 139 unsigned short epoch; 140 }; 141 142 struct hm_header_st 143 { 144 unsigned char type; 145 unsigned long msg_len; 146 unsigned short seq; 147 unsigned long frag_off; 148 unsigned long frag_len; 149 unsigned int is_ccs; 150 struct dtls1_retransmit_state saved_retransmit_state; 151 }; 152 153 struct ccs_header_st 154 { 155 unsigned char type; 156 unsigned short seq; 157 }; 158 159 struct dtls1_timeout_st 160 { 161 /* Number of read timeouts so far */ 162 unsigned int read_timeouts; 163 164 /* Number of write timeouts so far */ 165 unsigned int write_timeouts; 166 167 /* Number of alerts received so far */ 168 unsigned int num_alerts; 169 }; 170 171 typedef struct record_pqueue_st 172 { 173 unsigned short epoch; 174 pqueue q; 175 } record_pqueue; 176 177 typedef struct hm_fragment_st 178 { 179 struct hm_header_st msg_header; 180 unsigned char *fragment; 181 unsigned char *reassembly; 182 } hm_fragment; 183 184 typedef struct dtls1_state_st 185 { 186 unsigned int send_cookie; 187 unsigned char cookie[DTLS1_COOKIE_LENGTH]; 188 unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH]; 189 unsigned int cookie_len; 190 191 /* 192 * The current data and handshake epoch. This is initially 193 * undefined, and starts at zero once the initial handshake is 194 * completed 195 */ 196 unsigned short r_epoch; 197 unsigned short w_epoch; 198 199 /* records being received in the current epoch */ 200 DTLS1_BITMAP bitmap; 201 202 /* renegotiation starts a new set of sequence numbers */ 203 DTLS1_BITMAP next_bitmap; 204 205 /* handshake message numbers */ 206 unsigned short handshake_write_seq; 207 unsigned short next_handshake_write_seq; 208 209 unsigned short handshake_read_seq; 210 211 /* save last sequence number for retransmissions */ 212 unsigned char last_write_sequence[8]; 213 214 /* Received handshake records (processed and unprocessed) */ 215 record_pqueue unprocessed_rcds; 216 record_pqueue processed_rcds; 217 218 /* Buffered handshake messages */ 219 pqueue buffered_messages; 220 221 /* Buffered (sent) handshake records */ 222 pqueue sent_messages; 223 224 /* Buffered application records. 225 * Only for records between CCS and Finished 226 * to prevent either protocol violation or 227 * unnecessary message loss. 228 */ 229 record_pqueue buffered_app_data; 230 231 /* Is set when listening for new connections with dtls1_listen() */ 232 unsigned int listen; 233 234 unsigned int mtu; /* max DTLS packet size */ 235 236 struct hm_header_st w_msg_hdr; 237 struct hm_header_st r_msg_hdr; 238 239 struct dtls1_timeout_st timeout; 240 241 /* Indicates when the last handshake msg or heartbeat sent will timeout */ 242 struct timeval next_timeout; 243 244 /* Timeout duration */ 245 unsigned short timeout_duration; 246 247 /* storage for Alert/Handshake protocol data received but not 248 * yet processed by ssl3_read_bytes: */ 249 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH]; 250 unsigned int alert_fragment_len; 251 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH]; 252 unsigned int handshake_fragment_len; 253 254 unsigned int retransmitting; 255 unsigned int change_cipher_spec_ok; 256 257 #ifndef OPENSSL_NO_SCTP 258 /* used when SSL_ST_XX_FLUSH is entered */ 259 int next_state; 260 261 int shutdown_received; 262 #endif 263 264 } DTLS1_STATE; 265 266 typedef struct dtls1_record_data_st 267 { 268 unsigned char *packet; 269 unsigned int packet_length; 270 SSL3_BUFFER rbuf; 271 SSL3_RECORD rrec; 272 #ifndef OPENSSL_NO_SCTP 273 struct bio_dgram_sctp_rcvinfo recordinfo; 274 #endif 275 } DTLS1_RECORD_DATA; 276 277 #endif 278 279 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */ 280 #define DTLS1_TMO_READ_COUNT 2 281 #define DTLS1_TMO_WRITE_COUNT 2 282 283 #define DTLS1_TMO_ALERT_COUNT 12 284 285 #ifdef __cplusplus 286 } 287 #endif 288 #endif 289