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 83 extern "C" { 84 #endif 85 86 # define DTLS1_VERSION 0xFEFF 87 # define DTLS_MAX_VERSION DTLS1_VERSION 88 # define DTLS1_VERSION_MAJOR 0xFE 89 90 # define DTLS1_BAD_VER 0x0100 91 92 # if 0 93 /* this alert description is not specified anywhere... */ 94 # define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110 95 # endif 96 97 /* lengths of messages */ 98 # define DTLS1_COOKIE_LENGTH 256 99 100 # define DTLS1_RT_HEADER_LENGTH 13 101 102 # define DTLS1_HM_HEADER_LENGTH 12 103 104 # define DTLS1_HM_BAD_FRAGMENT -2 105 # define DTLS1_HM_FRAGMENT_RETRY -3 106 107 # define DTLS1_CCS_HEADER_LENGTH 1 108 109 # ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110 # define DTLS1_AL_HEADER_LENGTH 7 111 # else 112 # define DTLS1_AL_HEADER_LENGTH 2 113 # endif 114 115 # ifndef OPENSSL_NO_SSL_INTERN 116 117 # ifndef OPENSSL_NO_SCTP 118 # define DTLS1_SCTP_AUTH_LABEL "EXPORTER_DTLS_OVER_SCTP" 119 # endif 120 121 /* Max MTU overhead we know about so far is 40 for IPv6 + 8 for UDP */ 122 # define DTLS1_MAX_MTU_OVERHEAD 48 123 124 typedef struct dtls1_bitmap_st { 125 unsigned long map; /* track 32 packets on 32-bit systems and 64 126 * - on 64-bit systems */ 127 unsigned char max_seq_num[8]; /* max record number seen so far, 64-bit 128 * value in big-endian encoding */ 129 } DTLS1_BITMAP; 130 131 struct dtls1_retransmit_state { 132 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */ 133 EVP_MD_CTX *write_hash; /* used for mac generation */ 134 # ifndef OPENSSL_NO_COMP 135 COMP_CTX *compress; /* compression */ 136 # else 137 char *compress; 138 # endif 139 SSL_SESSION *session; 140 unsigned short epoch; 141 }; 142 143 struct hm_header_st { 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 unsigned char type; 155 unsigned short seq; 156 }; 157 158 struct dtls1_timeout_st { 159 /* Number of read timeouts so far */ 160 unsigned int read_timeouts; 161 /* Number of write timeouts so far */ 162 unsigned int write_timeouts; 163 /* Number of alerts received so far */ 164 unsigned int num_alerts; 165 }; 166 167 typedef struct record_pqueue_st { 168 unsigned short epoch; 169 pqueue q; 170 } record_pqueue; 171 172 typedef struct hm_fragment_st { 173 struct hm_header_st msg_header; 174 unsigned char *fragment; 175 unsigned char *reassembly; 176 } hm_fragment; 177 178 typedef struct dtls1_state_st { 179 unsigned int send_cookie; 180 unsigned char cookie[DTLS1_COOKIE_LENGTH]; 181 unsigned char rcvd_cookie[DTLS1_COOKIE_LENGTH]; 182 unsigned int cookie_len; 183 /* 184 * The current data and handshake epoch. This is initially 185 * undefined, and starts at zero once the initial handshake is 186 * completed 187 */ 188 unsigned short r_epoch; 189 unsigned short w_epoch; 190 /* records being received in the current epoch */ 191 DTLS1_BITMAP bitmap; 192 /* renegotiation starts a new set of sequence numbers */ 193 DTLS1_BITMAP next_bitmap; 194 /* handshake message numbers */ 195 unsigned short handshake_write_seq; 196 unsigned short next_handshake_write_seq; 197 unsigned short handshake_read_seq; 198 /* save last sequence number for retransmissions */ 199 unsigned char last_write_sequence[8]; 200 /* Received handshake records (processed and unprocessed) */ 201 record_pqueue unprocessed_rcds; 202 record_pqueue processed_rcds; 203 /* Buffered handshake messages */ 204 pqueue buffered_messages; 205 /* Buffered (sent) handshake records */ 206 pqueue sent_messages; 207 /* 208 * Buffered application records. Only for records between CCS and 209 * Finished to prevent either protocol violation or unnecessary message 210 * loss. 211 */ 212 record_pqueue buffered_app_data; 213 /* Is set when listening for new connections with dtls1_listen() */ 214 unsigned int listen; 215 unsigned int link_mtu; /* max on-the-wire DTLS packet size */ 216 unsigned int mtu; /* max DTLS packet size */ 217 struct hm_header_st w_msg_hdr; 218 struct hm_header_st r_msg_hdr; 219 struct dtls1_timeout_st timeout; 220 /* 221 * Indicates when the last handshake msg or heartbeat sent will timeout 222 */ 223 struct timeval next_timeout; 224 /* Timeout duration */ 225 unsigned short timeout_duration; 226 /* 227 * storage for Alert/Handshake protocol data received but not yet 228 * processed by ssl3_read_bytes: 229 */ 230 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH]; 231 unsigned int alert_fragment_len; 232 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH]; 233 unsigned int handshake_fragment_len; 234 unsigned int retransmitting; 235 /* 236 * Set when the handshake is ready to process peer's ChangeCipherSpec message. 237 * Cleared after the message has been processed. 238 */ 239 unsigned int change_cipher_spec_ok; 240 # ifndef OPENSSL_NO_SCTP 241 /* used when SSL_ST_XX_FLUSH is entered */ 242 int next_state; 243 int shutdown_received; 244 # endif 245 } DTLS1_STATE; 246 247 typedef struct dtls1_record_data_st { 248 unsigned char *packet; 249 unsigned int packet_length; 250 SSL3_BUFFER rbuf; 251 SSL3_RECORD rrec; 252 # ifndef OPENSSL_NO_SCTP 253 struct bio_dgram_sctp_rcvinfo recordinfo; 254 # endif 255 } DTLS1_RECORD_DATA; 256 257 # endif 258 259 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */ 260 # define DTLS1_TMO_READ_COUNT 2 261 # define DTLS1_TMO_WRITE_COUNT 2 262 263 # define DTLS1_TMO_ALERT_COUNT 12 264 265 #ifdef __cplusplus 266 } 267 #endif 268 #endif 269