1 /* 2 * replay-database.h 3 * 4 * interface for a replay database for packet security 5 * 6 * David A. McGrew 7 * Cisco Systems, Inc. 8 */ 9 /* 10 * 11 * Copyright (c) 2001-2006, Cisco Systems, Inc. 12 * All rights reserved. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 18 * Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 21 * Redistributions in binary form must reproduce the above 22 * copyright notice, this list of conditions and the following 23 * disclaimer in the documentation and/or other materials provided 24 * with the distribution. 25 * 26 * Neither the name of the Cisco Systems, Inc. nor the names of its 27 * contributors may be used to endorse or promote products derived 28 * from this software without specific prior written permission. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 31 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 32 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 33 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 34 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 35 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 36 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 37 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 41 * OF THE POSSIBILITY OF SUCH DAMAGE. 42 * 43 */ 44 45 46 #ifndef REPLAY_DB_H 47 #define REPLAY_DB_H 48 49 #include "integers.h" /* for uint32_t */ 50 #include "datatypes.h" /* for v128_t */ 51 #include "err.h" /* for err_status_t */ 52 53 /* 54 * if the ith least significant bit is one, then the packet index 55 * window_end-i is in the database 56 */ 57 58 typedef struct { 59 uint32_t window_start; /* packet index of the first bit in bitmask */ 60 v128_t bitmask; 61 } rdb_t; 62 63 #define rdb_bits_in_bitmask (8*sizeof(v128_t)) 64 65 /* 66 * rdb init 67 * 68 * initalizes rdb 69 * 70 * returns err_status_ok on success, err_status_t_fail otherwise 71 */ 72 73 err_status_t 74 rdb_init(rdb_t *rdb); 75 76 77 /* 78 * rdb_check 79 * 80 * checks to see if index appears in rdb 81 * 82 * returns err_status_fail if the index already appears in rdb, 83 * returns err_status_ok otherwise 84 */ 85 86 err_status_t 87 rdb_check(const rdb_t *rdb, uint32_t rdb_index); 88 89 /* 90 * rdb_add_index 91 * 92 * adds index to rdb_t (and does *not* check if index appears in db) 93 * 94 * returns err_status_ok on success, err_status_fail otherwise 95 * 96 */ 97 98 err_status_t 99 rdb_add_index(rdb_t *rdb, uint32_t rdb_index); 100 101 /* 102 * the functions rdb_increment() and rdb_get_value() are for use by 103 * senders, not receivers - DO NOT use these functions on the same 104 * rdb_t upon which rdb_add_index is used! 105 */ 106 107 108 /* 109 * rdb_increment(db) increments the sequence number in db, if it is 110 * not too high 111 * 112 * return values: 113 * 114 * err_status_ok no problem 115 * err_status_key_expired sequence number too high 116 * 117 */ 118 err_status_t 119 rdb_increment(rdb_t *rdb); 120 121 /* 122 * rdb_get_value(db) returns the current sequence number of db 123 */ 124 125 uint32_t 126 rdb_get_value(const rdb_t *rdb); 127 128 129 #endif /* REPLAY_DB_H */ 130