void process_packet(int socket) {
unsigned char *buffer;
int size = 0;
struct sockaddr_in recv_addr;
struct iphdr *ipheader;
struct ospfhdr *ospfheader;
unsigned int iphdr_len, recv_addr_len;
struct ospf_interface *oiface;
buffer = malloc(sizeof(*buffer)*REPLAY_PACKET_BUFFER);
memset(&recv_addr,0,sizeof(recv_addr));
recv_addr_len = sizeof(recv_addr);
size = recvfrom(socket, buffer, REPLAY_PACKET_BUFFER, 0, (struct sockaddr *)&recv_addr, &recv_addr_len);
if(size>0) {
oiface = find_oiface_by_socket(socket);
if(recv_addr.sin_addr.s_addr != oiface->iface->ip.s_addr) {
ipheader = (struct iphdr *)buffer;
iphdr_len = ipheader->ihl*4;
ospfheader = (struct ospfhdr *)(buffer+iphdr_len);
switch(ospfheader->mesg_type) {
case OSPF_MESG_HELLO:
process_hello(buffer+iphdr_len,ipheader->saddr,ipheader->daddr,((unsigned int)ntohs(ospfheader->packet_length)),oiface);
break;
case OSPF_MESG_DBDESC:
process_dbdesc(buffer+iphdr_len,ipheader->saddr,ipheader->daddr,((unsigned int)ntohs(ospfheader->packet_length)),oiface);
break;
case OSPF_MESG_LSR:
process_lsr(buffer+iphdr_len,ipheader->saddr,ipheader->daddr,((unsigned int)ntohs(ospfheader->packet_length)),oiface);
break;
case OSPF_MESG_LSU:
process_lsu(buffer+iphdr_len,ipheader->saddr,ipheader->daddr,((unsigned int)ntohs(ospfheader->packet_length)),oiface);
break;
case OSPF_MESG_LSACK:
process_lsack(buffer+iphdr_len,ipheader->saddr,ipheader->daddr,((unsigned int)ntohs(ospfheader->packet_length)),oiface);
break;
}
}
} else {
//error reading in packet
}
free(buffer);
}
void *recv_loop(void *p) {
uint8_t buf[BUFFER_SIZE];
interface *iface;
ospf_header *ospfhdr;
neighbor *nbr;
in_addr_t src;
while (*(int *)p) {
iface = recv_ospf(sock, buf, BUFFER_SIZE, &src);
ospfhdr = (ospf_header *)(buf + sizeof(struct iphdr));
/* check if the packet is from myself */
if (ospfhdr->router_id == myid) continue;
for (nbr = iface->nbrs; nbr; nbr = nbr->next)
if (ospfhdr->router_id == nbr->router_id) break;
switch (ospfhdr->type) {
case OSPF_TYPE_HELLO: process_hello(iface, nbr, ospfhdr, src); break;
case OSPF_TYPE_DD: process_dd(iface, nbr, ospfhdr); break;
case OSPF_TYPE_LSR: process_lsr(nbr, ospfhdr);break;
case OSPF_TYPE_LSU: process_lsu(iface->a, nbr, ospfhdr);break;
case OSPF_TYPE_LSACK: process_ack(nbr, ospfhdr);break;
default: break;
}
}
return NULL;
}