incubator-nuttx/net/inet/ipv6_build_header.c

82 lines
3.0 KiB
C

/****************************************************************************
* net/inet/ipv6_build_header.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 <debug.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/netconfig.h>
#include "inet.h"
#ifdef CONFIG_NET_IPv6
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ipv6_build_header
*
* Description:
* build IPv6 header
*
* Input Parameters:
* ipv6 Pointer to IPv6 header's buffer
* payload_len Length of the IPv6 payload(without IPv6 header length)
* prot Type of header immediately following the IPv6 header
* src_ip Source IPv6 address
* dst_ip Destination IPv6 address
* ttl Time to live(IPv4) hop limit(IPv6)
*
* Returned Value:
* length of IPv6 header
*
****************************************************************************/
uint16_t ipv6_build_header(FAR struct ipv6_hdr_s *ipv6, uint16_t payload_len,
uint16_t prot, const net_ipv6addr_t src_ip,
const net_ipv6addr_t dst_ip, uint8_t ttl)
{
/* Set up the IPv6 header */
ipv6->vtc = 0x60; /* Version/traffic class (MS) */
ipv6->tcf = 0; /* Traffic class(LS)/Flow label(MS) */
ipv6->flow = 0; /* Flow label (LS) */
ipv6->len[0] = (payload_len >> 8); /* Length excludes the IPv6 header */
ipv6->len[1] = (payload_len & 0xff);
ipv6->proto = prot; /* Next header */
ipv6->ttl = ttl;
/* It's possible to use srcip to initialize destip */
net_ipv6addr_hdrcopy(ipv6->destipaddr, dst_ip);
net_ipv6addr_hdrcopy(ipv6->srcipaddr, src_ip);
ninfo("IPv6 Payload length: %d\n", payload_len);
return IPv6_HDRLEN;
}
#endif /* CONFIG_NET_IPv6 */