// IPv6 パケットのビルド
BUF *BuildIPv6(IPV6_ADDR *dest_ip, IPV6_ADDR *src_ip, UINT id, UCHAR protocol, UCHAR hop_limit, void *data,
UINT size)
{
IPV6_HEADER_PACKET_INFO info;
IPV6_HEADER ip_header;
BUF *buf;
UINT size_for_headers;
// 引数チェック
if (dest_ip == NULL || src_ip == NULL || data == NULL)
{
return NULL;
}
if (hop_limit == 0)
{
hop_limit = 255;
}
// IPv6 ヘッダ
Zero(&ip_header, sizeof(ip_header));
IPV6_SET_VERSION(&ip_header, 6);
ip_header.HopLimit = hop_limit;
Copy(&ip_header.SrcAddress, src_ip, sizeof(IPV6_ADDR));
Copy(&ip_header.DestAddress, dest_ip, sizeof(IPV6_ADDR));
// ヘッダパケット情報の整理
Zero(&info, sizeof(info));
info.IPv6Header = &ip_header;
info.Protocol = protocol;
info.Payload = data;
info.PayloadSize = size;
buf = BuildIPv6PacketHeader(&info, &size_for_headers);
if (buf == NULL)
{
return NULL;
}
return buf;
}
void add_ip_header (
char *position,
char *original_packet_position,
int ip_payload_length,
lisp_addr_t *src_addr,
lisp_addr_t *dst_addr)
{
struct iphdr *iph = NULL;
struct iphdr *inner_iph = NULL;
struct ip6_hdr *ip6h = NULL;
struct ip6_hdr *inner_ip6h = NULL;
uint8_t tos = 0;
uint8_t ttl = 0;
inner_iph = (struct iphdr *) original_packet_position;
/* We SHOULD copy ttl and tos fields from the inner packet to the encapsulated one */
if (inner_iph->version == 4 ) {
tos = inner_iph->tos;
ttl = inner_iph->ttl;
} else {
inner_ip6h = (struct ip6_hdr *) original_packet_position;
ttl = inner_ip6h->ip6_hops; /* ttl = Hops limit in IPv6 */
//tos = (inner_ip6h->ip6_flow & 0x0ff00000) >> 20; /* 4 bits version, 8 bits Traffic Class, 20 bits flow-ID */
tos = IPV6_GET_TC(*inner_ip6h); /* tos = Traffic class field in IPv6 */
}
/*
* Construct and add the outer ip header
*/
switch (dst_addr->afi){
case AF_INET:
iph = (struct iphdr *) position;
iph->version = 4;
//iph->ihl = sizeof ( struct iphdr ) >>2;
iph->ihl = 5; /* Minimal IPv4 header */ /*XXX Beware, hardcoded. Supposing no IP options */
iph->tos = tos;
iph->tot_len = htons(ip_payload_length);
iph->frag_off = htons(IP_DF); /* Do not fragment flag. See 5.4.1 in LISP RFC (6830) */
iph->ttl = ttl;
iph->protocol = IPPROTO_UDP;
iph->check = 0; //Computed by the NIC (checksum offloading)
iph->daddr = dst_addr->address.ip.s_addr;
iph->saddr = src_addr->address.ip.s_addr;
break;
case AF_INET6:
ip6h = ( struct ip6_hdr *) position;
IPV6_SET_VERSION(ip6h, 6);
IPV6_SET_TC(ip6h,tos);
IPV6_SET_FLOW_LABEL(ip6h,0);
ip6h->ip6_plen = htons(ip_payload_length);
ip6h->ip6_nxt = IPPROTO_UDP;
ip6h->ip6_hops = ttl;
memcopy_lisp_addr(&(ip6h->ip6_dst),dst_addr);
memcopy_lisp_addr(&(ip6h->ip6_src),src_addr);
break;
default:
break;
}
}
