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 79 extern "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 109 110 111 typedef 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; 117 118 struct 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 }; 130 131 struct 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 }; 141 142 struct ccs_header_st 143 { 144 unsigned char type; 145 unsigned short seq; 146 }; 147 148 struct 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 }; 159 160 typedef struct record_pqueue_st 161 { 162 unsigned short epoch; 163 pqueue q; 164 } record_pqueue; 165 166 typedef struct hm_fragment_st 167 { 168 struct hm_header_st msg_header; 169 unsigned char *fragment; 170 unsigned char *reassembly; 171 } hm_fragment; 172 173 typedef 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; 247 248 typedef 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