michael@0: /*
michael@0:  * replay-database.h
michael@0:  *
michael@0:  * interface for a replay database for packet security
michael@0:  *
michael@0:  * David A. McGrew
michael@0:  * Cisco Systems, Inc.
michael@0:  */
michael@0: /*
michael@0:  *	
michael@0:  * Copyright (c) 2001-2006, Cisco Systems, Inc.
michael@0:  * All rights reserved.
michael@0:  * 
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 
michael@0:  *   Redistributions of source code must retain the above copyright
michael@0:  *   notice, this list of conditions and the following disclaimer.
michael@0:  * 
michael@0:  *   Redistributions in binary form must reproduce the above
michael@0:  *   copyright notice, this list of conditions and the following
michael@0:  *   disclaimer in the documentation and/or other materials provided
michael@0:  *   with the distribution.
michael@0:  * 
michael@0:  *   Neither the name of the Cisco Systems, Inc. nor the names of its
michael@0:  *   contributors may be used to endorse or promote products derived
michael@0:  *   from this software without specific prior written permission.
michael@0:  * 
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
michael@0:  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
michael@0:  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
michael@0:  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
michael@0:  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
michael@0:  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
michael@0:  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
michael@0:  * OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: 
michael@0: #ifndef REPLAY_DB_H
michael@0: #define REPLAY_DB_H
michael@0: 
michael@0: #include "integers.h"         /* for uint32_t     */
michael@0: #include "datatypes.h"        /* for v128_t       */
michael@0: #include "err.h"              /* for err_status_t */
michael@0: 
michael@0: /*
michael@0:  * if the ith least significant bit is one, then the packet index
michael@0:  * window_end-i is in the database
michael@0:  */
michael@0: 
michael@0: typedef struct {
michael@0:   uint32_t window_start;   /* packet index of the first bit in bitmask */
michael@0:   v128_t bitmask;  
michael@0: } rdb_t;
michael@0: 
michael@0: #define rdb_bits_in_bitmask (8*sizeof(v128_t))   
michael@0: 
michael@0: /*
michael@0:  * rdb init
michael@0:  *
michael@0:  * initalizes rdb
michael@0:  *
michael@0:  * returns err_status_ok on success, err_status_t_fail otherwise
michael@0:  */
michael@0: 
michael@0: err_status_t
michael@0: rdb_init(rdb_t *rdb);
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * rdb_check
michael@0:  *
michael@0:  * checks to see if index appears in rdb
michael@0:  *
michael@0:  * returns err_status_fail if the index already appears in rdb,
michael@0:  * returns err_status_ok otherwise
michael@0:  */
michael@0: 
michael@0: err_status_t
michael@0: rdb_check(const rdb_t *rdb, uint32_t rdb_index);  
michael@0: 
michael@0: /*
michael@0:  * rdb_add_index
michael@0:  *
michael@0:  * adds index to rdb_t (and does *not* check if index appears in db)
michael@0:  *
michael@0:  * returns err_status_ok on success, err_status_fail otherwise
michael@0:  *
michael@0:  */
michael@0: 
michael@0: err_status_t
michael@0: rdb_add_index(rdb_t *rdb, uint32_t rdb_index);
michael@0: 
michael@0: /*
michael@0:  * the functions rdb_increment() and rdb_get_value() are for use by 
michael@0:  * senders, not receivers - DO NOT use these functions on the same
michael@0:  * rdb_t upon which rdb_add_index is used!
michael@0:  */
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * rdb_increment(db) increments the sequence number in db, if it is 
michael@0:  * not too high
michael@0:  *
michael@0:  * return values:
michael@0:  * 
michael@0:  *    err_status_ok            no problem
michael@0:  *    err_status_key_expired   sequence number too high
michael@0:  *
michael@0:  */
michael@0: err_status_t
michael@0: rdb_increment(rdb_t *rdb);
michael@0: 
michael@0: /*
michael@0:  * rdb_get_value(db) returns the current sequence number of db
michael@0:  */
michael@0: 
michael@0: uint32_t
michael@0: rdb_get_value(const rdb_t *rdb);
michael@0: 
michael@0: 
michael@0: #endif /* REPLAY_DB_H */