mirror of
https://github.com/ossrs/srs.git
synced 2025-03-09 15:49:59 +00:00
122 lines
3.7 KiB
C
122 lines
3.7 KiB
C
/*
|
|
* key.c
|
|
*
|
|
* key usage limits enforcement
|
|
*
|
|
* David A. Mcgrew
|
|
* 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
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
|
|
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
|
|
* OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include <config.h>
|
|
#endif
|
|
|
|
#include "key.h"
|
|
|
|
#define soft_limit 0x10000
|
|
|
|
srtp_err_status_t srtp_key_limit_set(srtp_key_limit_t key,
|
|
const srtp_xtd_seq_num_t s)
|
|
{
|
|
#ifdef NO_64BIT_MATH
|
|
if (high32(s) == 0 && low32(s) < soft_limit) {
|
|
return srtp_err_status_bad_param;
|
|
}
|
|
#else
|
|
if (s < soft_limit) {
|
|
return srtp_err_status_bad_param;
|
|
}
|
|
#endif
|
|
key->num_left = s;
|
|
key->state = srtp_key_state_normal;
|
|
return srtp_err_status_ok;
|
|
}
|
|
|
|
srtp_err_status_t srtp_key_limit_clone(srtp_key_limit_t original,
|
|
srtp_key_limit_t *new_key)
|
|
{
|
|
if (original == NULL) {
|
|
return srtp_err_status_bad_param;
|
|
}
|
|
*new_key = original;
|
|
return srtp_err_status_ok;
|
|
}
|
|
|
|
srtp_err_status_t srtp_key_limit_check(const srtp_key_limit_t key)
|
|
{
|
|
if (key->state == srtp_key_state_expired) {
|
|
return srtp_err_status_key_expired;
|
|
}
|
|
return srtp_err_status_ok;
|
|
}
|
|
|
|
srtp_key_event_t srtp_key_limit_update(srtp_key_limit_t key)
|
|
{
|
|
#ifdef NO_64BIT_MATH
|
|
if (low32(key->num_left) == 0) {
|
|
// carry
|
|
key->num_left =
|
|
make64(high32(key->num_left) - 1, low32(key->num_left) - 1);
|
|
} else {
|
|
// no carry
|
|
key->num_left = make64(high32(key->num_left), low32(key->num_left) - 1);
|
|
}
|
|
if (high32(key->num_left) != 0 || low32(key->num_left) >= soft_limit) {
|
|
return srtp_key_event_normal; /* we're above the soft limit */
|
|
}
|
|
#else
|
|
key->num_left--;
|
|
if (key->num_left >= soft_limit) {
|
|
return srtp_key_event_normal; /* we're above the soft limit */
|
|
}
|
|
#endif
|
|
if (key->state == srtp_key_state_normal) {
|
|
/* we just passed the soft limit, so change the state */
|
|
key->state = srtp_key_state_past_soft_limit;
|
|
}
|
|
#ifdef NO_64BIT_MATH
|
|
if (low32(key->num_left) == 0 && high32(key->num_left == 0))
|
|
#else
|
|
if (key->num_left < 1)
|
|
#endif
|
|
{ /* we just hit the hard limit */
|
|
key->state = srtp_key_state_expired;
|
|
return srtp_key_event_hard_limit;
|
|
}
|
|
return srtp_key_event_soft_limit;
|
|
}
|