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 #ifndef HEADER_DTLS1_H 59 #define HEADER_DTLS1_H 60 61 #include <openssl/base.h> 62 #include <openssl/buf.h> 63 #include <openssl/pqueue.h> 64 65 #ifdef __cplusplus 66 extern "C" { 67 #endif 68 69 70 #define DTLS1_VERSION 0xFEFF 71 #define DTLS1_2_VERSION 0xFEFD 72 /* Special value for method supporting multiple versions */ 73 #define DTLS_ANY_VERSION 0x1FFFF 74 75 #if 0 76 /* this alert description is not specified anywhere... */ 77 #define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 110 78 #endif 79 80 /* lengths of messages */ 81 #define DTLS1_COOKIE_LENGTH 256 82 83 #define DTLS1_RT_HEADER_LENGTH 13 84 85 #define DTLS1_HM_HEADER_LENGTH 12 86 87 #define DTLS1_HM_BAD_FRAGMENT -2 88 #define DTLS1_HM_FRAGMENT_RETRY -3 89 90 #define DTLS1_CCS_HEADER_LENGTH 1 91 92 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 93 #define DTLS1_AL_HEADER_LENGTH 7 94 #else 95 #define DTLS1_AL_HEADER_LENGTH 2 96 #endif 97 98 #ifndef OPENSSL_NO_SSL_INTERN 99 100 101 #if defined(OPENSSL_WINDOWS) 102 /* Because of Windows header issues, we can't get the normal declaration of 103 * timeval. */ 104 typedef struct OPENSSL_timeval_st { 105 long tv_sec; 106 long tv_usec; 107 } OPENSSL_timeval; 108 #else 109 #include <sys/time.h> 110 typedef struct timeval OPENSSL_timeval; 111 #endif 112 113 typedef struct dtls1_bitmap_st 114 { 115 unsigned long map; /* track 32 packets on 32-bit systems 116 and 64 - on 64-bit systems */ 117 unsigned char max_seq_num[8]; /* max record number seen so far, 118 64-bit value in big-endian 119 encoding */ 120 } DTLS1_BITMAP; 121 122 struct dtls1_retransmit_state 123 { 124 EVP_CIPHER_CTX *enc_write_ctx; /* cryptographic state */ 125 EVP_MD_CTX *write_hash; /* used for mac generation */ 126 SSL_SESSION *session; 127 unsigned short epoch; 128 }; 129 130 struct hm_header_st 131 { 132 unsigned char type; 133 unsigned long msg_len; 134 unsigned short seq; 135 unsigned long frag_off; 136 unsigned long frag_len; 137 unsigned int is_ccs; 138 struct dtls1_retransmit_state saved_retransmit_state; 139 }; 140 141 struct ccs_header_st 142 { 143 unsigned char type; 144 unsigned short seq; 145 }; 146 147 struct dtls1_timeout_st 148 { 149 /* Number of read timeouts so far */ 150 unsigned int read_timeouts; 151 152 /* Number of write timeouts so far */ 153 unsigned int write_timeouts; 154 155 /* Number of alerts received so far */ 156 unsigned int num_alerts; 157 }; 158 159 typedef struct record_pqueue_st 160 { 161 unsigned short epoch; 162 pqueue q; 163 } record_pqueue; 164 165 typedef struct hm_fragment_st 166 { 167 struct hm_header_st msg_header; 168 unsigned char *fragment; 169 unsigned char *reassembly; 170 } hm_fragment; 171 172 typedef struct dtls1_state_st 173 { 174 /* send_cookie is true if we are resending the ClientHello 175 * with a cookie from a HelloVerifyRequest. */ 176 unsigned int send_cookie; 177 178 uint8_t cookie[DTLS1_COOKIE_LENGTH]; 179 size_t cookie_len; 180 181 /* 182 * The current data and handshake epoch. This is initially 183 * undefined, and starts at zero once the initial handshake is 184 * completed 185 */ 186 unsigned short r_epoch; 187 unsigned short w_epoch; 188 189 /* records being received in the current epoch */ 190 DTLS1_BITMAP bitmap; 191 192 /* renegotiation starts a new set of sequence numbers */ 193 DTLS1_BITMAP next_bitmap; 194 195 /* handshake message numbers */ 196 unsigned short handshake_write_seq; 197 unsigned short next_handshake_write_seq; 198 199 unsigned short handshake_read_seq; 200 201 /* save last sequence number for retransmissions */ 202 unsigned char last_write_sequence[8]; 203 204 /* Received handshake records (processed and unprocessed) */ 205 record_pqueue unprocessed_rcds; 206 record_pqueue processed_rcds; 207 208 /* Buffered handshake messages */ 209 pqueue buffered_messages; 210 211 /* Buffered (sent) handshake records */ 212 pqueue sent_messages; 213 214 /* Buffered application records. 215 * Only for records between CCS and Finished 216 * to prevent either protocol violation or 217 * unnecessary message loss. 218 */ 219 record_pqueue buffered_app_data; 220 221 /* Is set when listening for new connections with dtls1_listen() */ 222 unsigned int listen; 223 224 unsigned int mtu; /* max DTLS packet size */ 225 226 struct hm_header_st w_msg_hdr; 227 struct hm_header_st r_msg_hdr; 228 229 struct dtls1_timeout_st timeout; 230 231 /* Indicates when the last handshake msg or heartbeat sent will 232 * timeout. Because of header issues on Windows, this cannot actually 233 * be a struct timeval. */ 234 OPENSSL_timeval next_timeout; 235 236 /* Timeout duration */ 237 unsigned short timeout_duration; 238 239 /* storage for Alert/Handshake protocol data received but not 240 * yet processed by ssl3_read_bytes: */ 241 unsigned char alert_fragment[DTLS1_AL_HEADER_LENGTH]; 242 unsigned int alert_fragment_len; 243 unsigned char handshake_fragment[DTLS1_HM_HEADER_LENGTH]; 244 unsigned int handshake_fragment_len; 245 246 unsigned int retransmitting; 247 unsigned int change_cipher_spec_ok; 248 } DTLS1_STATE; 249 250 typedef struct dtls1_record_data_st 251 { 252 unsigned char *packet; 253 unsigned int packet_length; 254 SSL3_BUFFER rbuf; 255 SSL3_RECORD rrec; 256 } DTLS1_RECORD_DATA; 257 258 #endif 259 260 /* Timeout multipliers (timeout slice is defined in apps/timeouts.h */ 261 #define DTLS1_TMO_READ_COUNT 2 262 #define DTLS1_TMO_WRITE_COUNT 2 263 264 #define DTLS1_TMO_ALERT_COUNT 12 265 266 #ifdef __cplusplus 267 } 268 #endif 269 #endif 270 271
