incubator-nuttx/net/utils/net_ipv6_payload.c

75 lines
2.5 KiB
C

/****************************************************************************
* net/utils/net_ipv6_payload.c
*
* 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/config.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/ipv6ext.h>
#ifdef CONFIG_NET_IPv6
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: net_ipv6_payload
*
* Description:
* Given a pointer to the IPv6 header, this function will return a pointer
* to the beginning of the L4 payload.
*
* Input Parameters:
* ipv6 - A pointer to the IPv6 header.
* proto - The location to return the protocol number in the IPv6 header.
*
* Returned Value:
* A pointer to the beginning of the payload.
*
****************************************************************************/
FAR void *net_ipv6_payload(FAR struct ipv6_hdr_s *ipv6, FAR uint8_t *proto)
{
FAR struct ipv6_extension_s *exthdr;
FAR uint8_t *payload = (FAR uint8_t *)ipv6 + IPv6_HDRLEN;
uint8_t nxthdr = ipv6->proto;
uint16_t extlen;
while (ipv6_exthdr(nxthdr))
{
/* Just skip over the extension header */
exthdr = (FAR struct ipv6_extension_s *)payload;
extlen = EXTHDR_LEN(exthdr->len);
payload += extlen;
nxthdr = exthdr->nxthdr;
}
*proto = nxthdr;
return payload;
}
#endif /* CONFIG_NET_IPv6 */