incubator-nuttx/net/icmpv6/icmpv6_pmtu.c

120 lines
3.6 KiB
C

/****************************************************************************
* net/icmpv6/icmpv6_pmtu.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/clock.h>
#include "icmpv6/icmpv6.h"
/****************************************************************************
* Private Data
****************************************************************************/
static struct icmpv6_pmtu_entry
g_icmpv6_pmtu_entry[CONFIG_NET_ICMPv6_PMTU_ENTRIES];
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: icmpv6_find_pmtu_entry
*
* Description:
* Search for a ipv6 pmtu entry
*
* Parameters:
* destipaddr the IPv6 address of the destination
*
* Return:
* not null is success; null is failure
****************************************************************************/
FAR struct icmpv6_pmtu_entry *
icmpv6_find_pmtu_entry(net_ipv6addr_t destipaddr)
{
clock_t now = clock_systime_ticks();
int i;
for (i = 0; i < CONFIG_NET_ICMPv6_PMTU_ENTRIES; i++)
{
if (g_icmpv6_pmtu_entry[i].pmtu == 0)
{
continue;
}
if (net_ipv6addr_cmp(destipaddr, g_icmpv6_pmtu_entry[i].daddr))
{
g_icmpv6_pmtu_entry[i].time = now;
return &g_icmpv6_pmtu_entry[i];
}
}
return NULL;
}
/****************************************************************************
* Name: icmpv6_add_pmtu_entry
*
* Description:
* Create a new ipv6 destination cache entry. If no unused entry is found,
* will recycle oldest entry
*
* Parameters:
* destipaddr the IPv6 address of the destination
* mtu MTU
*
* Return:
* void
****************************************************************************/
void icmpv6_add_pmtu_entry(net_ipv6addr_t destipaddr, int mtu)
{
clock_t now = clock_systime_ticks();
int j = 0;
int i;
for (i = 0; i < CONFIG_NET_ICMPv6_PMTU_ENTRIES; i++)
{
if (g_icmpv6_pmtu_entry[i].pmtu == 0 ||
(sclock_t)(now - g_icmpv6_pmtu_entry[i].time) >=
SEC2TICK(CONFIG_NET_ICMPv6_PMTU_TIMEOUT * 60))
{
j = i;
break;
}
if ((sclock_t)(g_icmpv6_pmtu_entry[i].time -
g_icmpv6_pmtu_entry[j].time) < 0)
{
j = i;
}
}
net_ipv6addr_copy(g_icmpv6_pmtu_entry[j].daddr, destipaddr);
g_icmpv6_pmtu_entry[j].pmtu = mtu;
g_icmpv6_pmtu_entry[j].time = now;
}