diff options
Diffstat (limited to 'crypto/replay/rdb.c')
| -rw-r--r-- | crypto/replay/rdb.c | 134 |
1 files changed, 67 insertions, 67 deletions
diff --git a/crypto/replay/rdb.c b/crypto/replay/rdb.c index 19eca79..ab1c7b5 100644 --- a/crypto/replay/rdb.c +++ b/crypto/replay/rdb.c @@ -8,26 +8,26 @@ */ /* - * - * Copyright (c) 2001-2005, Cisco Systems, Inc. + * + * Copyright (c) 2001-2017, Cisco Systems, Inc. * All rights reserved. - * + * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: - * + * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. - * + * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. - * + * * Neither the name of the Cisco Systems, Inc. nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. - * + * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS @@ -43,95 +43,95 @@ * */ +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif #include "rdb.h" - /* * this implementation of a replay database works as follows: - * + * * window_start is the index of the first packet in the window * bitmask a bit-buffer, containing the most recently entered - * index as the leftmost bit + * index as the leftmost bit * */ -/* rdb_init initalizes rdb */ - -err_status_t -rdb_init(rdb_t *rdb) { - v128_set_to_zero(&rdb->bitmask); - rdb->window_start = 0; - return err_status_ok; +/* srtp_rdb_init initalizes rdb */ +srtp_err_status_t srtp_rdb_init(srtp_rdb_t *rdb) +{ + v128_set_to_zero(&rdb->bitmask); + rdb->window_start = 0; + return srtp_err_status_ok; } /* - * rdb_check checks to see if index appears in rdb + * srtp_rdb_check checks to see if index appears in rdb */ - -err_status_t -rdb_check(const rdb_t *rdb, uint32_t index) { - - /* if the index appears after (or at very end of) the window, its good */ - if (index > rdb->window_start + rdb_bits_in_bitmask) - return err_status_ok; - - /* if the index appears before the window, its bad */ - if (index < rdb->window_start) - return err_status_fail; - - /* otherwise, the index appears within the window, so check the bitmask */ - if (v128_get_bit(&rdb->bitmask, (index - rdb->window_start)) == 1) - return err_status_fail; - - /* otherwise, the index is okay */ - return err_status_ok; +srtp_err_status_t srtp_rdb_check(const srtp_rdb_t *rdb, uint32_t p_index) +{ + /* if the index appears after (or at very end of) the window, its good */ + if (p_index >= rdb->window_start + rdb_bits_in_bitmask) { + return srtp_err_status_ok; + } + + /* if the index appears before the window, its bad */ + if (p_index < rdb->window_start) { + return srtp_err_status_replay_old; + } + + /* otherwise, the index appears within the window, so check the bitmask */ + if (v128_get_bit(&rdb->bitmask, (p_index - rdb->window_start)) == 1) { + return srtp_err_status_replay_fail; + } + + /* otherwise, the index is okay */ + return srtp_err_status_ok; } /* - * rdb_add_index adds index to rdb_t (and does *not* check if + * srtp_rdb_add_index adds index to srtp_rdb_t (and does *not* check if * index appears in db) * - * this function should be called only after rdb_check has + * this function should be called only after srtp_rdb_check has * indicated that the index does not appear in the rdb, e.g., a mutex * should protect the rdb between these calls */ +srtp_err_status_t srtp_rdb_add_index(srtp_rdb_t *rdb, uint32_t p_index) +{ + unsigned int delta; -err_status_t -rdb_add_index(rdb_t *rdb, uint32_t index) { - int delta; - - /* here we *assume* that index > rdb->window_start */ + if (p_index < rdb->window_start) + return srtp_err_status_replay_fail; - delta = (index - rdb->window_start); - if (delta < rdb_bits_in_bitmask) { + delta = (p_index - rdb->window_start); + if (delta < rdb_bits_in_bitmask) { + /* if the p_index is within the window, set the appropriate bit */ + v128_set_bit(&rdb->bitmask, delta); - /* if the index is within the window, set the appropriate bit */ - v128_set_bit(&rdb->bitmask, delta); + } else { + delta -= rdb_bits_in_bitmask - 1; - } else { - - delta -= rdb_bits_in_bitmask; + /* shift the window forward by delta bits*/ + v128_left_shift(&rdb->bitmask, delta); + v128_set_bit(&rdb->bitmask, rdb_bits_in_bitmask - 1); + rdb->window_start += delta; + } - /* shift the window forward by delta bits*/ - v128_left_shift(&rdb->bitmask, delta); - v128_set_bit(&rdb->bitmask, rdb_bits_in_bitmask-delta); - rdb->window_start += delta; - - } - - return err_status_ok; + return srtp_err_status_ok; } -err_status_t -rdb_increment(rdb_t *rdb) { - - if (rdb->window_start++ > 0x7fffffff) - return err_status_key_expired; - return err_status_ok; +srtp_err_status_t srtp_rdb_increment(srtp_rdb_t *rdb) +{ + if (rdb->window_start >= 0x7fffffff) { + return srtp_err_status_key_expired; + } + ++rdb->window_start; + return srtp_err_status_ok; } -uint32_t -rdb_get_value(const rdb_t *rdb) { - return rdb->window_start; +uint32_t srtp_rdb_get_value(const srtp_rdb_t *rdb) +{ + return rdb->window_start; } |
