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      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 #include <sys/time.h>
     76 #endif
     77 
     78 #ifdef  __cplusplus
     79 extern "C" {
     80 #endif
     81 
     82 #define DTLS1_VERSION			0xFEFF
     83 #define DTLS1_BAD_VER			0x0100
     84 
     85 #if 0
     86 /* this alert description is not specified anywhere... */
     87 #define DTLS1_AD_MISSING_HANDSHAKE_MESSAGE    110
     88 #endif
     89 
     90 /* lengths of messages */
     91 #define DTLS1_COOKIE_LENGTH                     256
     92 
     93 #define DTLS1_RT_HEADER_LENGTH                  13
     94 
     95 #define DTLS1_HM_HEADER_LENGTH                  12
     96 
     97 #define DTLS1_HM_BAD_FRAGMENT                   -2
     98 #define DTLS1_HM_FRAGMENT_RETRY                 -3
     99 
    100 #define DTLS1_CCS_HEADER_LENGTH                  1
    101 
    102 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
    103 #define DTLS1_AL_HEADER_LENGTH                   7
    104 #else
    105 #define DTLS1_AL_HEADER_LENGTH                   2
    106 #endif
    107 
    108 
    109 typedef struct dtls1_bitmap_st
    110 	{
    111 	unsigned long map;		/* track 32 packets on 32-bit systems
    112 					   and 64 - on 64-bit systems */
    113 	unsigned char max_seq_num[8];	/* max record number seen so far,
    114 					   64-bit value in big-endian
    115 					   encoding */
    116 	} DTLS1_BITMAP;
    117 
    118 struct dtls1_retransmit_state
    119 	{
    120 	EVP_CIPHER_CTX *enc_write_ctx;	/* cryptographic state */
    121 	EVP_MD_CTX *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 
    268