/* Process encapsulated map request header: lisp header and the interal IP and
* UDP header */
int
lisp_msg_ecm_decap(lbuf_t *pkt, uint16_t *src_port)
{
uint16_t ipsum = 0;
uint16_t udpsum = 0;
int udp_len = 0;
struct udphdr *udph;
struct ip *iph;
/* this is the new start of the packet */
lisp_msg_pull_ecm_hdr(pkt);
/* Set and extract inner layer 3 packet */
lbuf_reset_l3(pkt);
iph = pkt_pull_ip(pkt);
/* Set and extract inner layer 4 packet */
lbuf_reset_l4(pkt);
udph = pkt_pull_udp(pkt);
/* Set the beginning of the LISP msg*/
lbuf_reset_lisp(pkt);
/* This should overwrite the external port (dst_port in map-reply =
* inner src_port in encap map-request) */
*src_port = ntohs(udph->source);
#ifdef BSD
udp_len = ntohs(udph->uh_ulen);
#else
udp_len = ntohs(udph->len);
#endif
/* Verify the checksums. */
if (iph->ip_v == IPVERSION) {
ipsum = ip_checksum((uint16_t *) iph, sizeof(struct ip));
if (ipsum != 0) {
OOR_LOG(LDBG_2, "IP checksum failed.");
}
}
/* Verify UDP checksum only if different from 0.
* This means we ACCEPT UDP checksum 0! */
if (udph->check != 0) {
udpsum = udp_checksum(udph, udp_len, iph,
ip_version_to_sock_afi(iph->ip_v));
if (udpsum != 0) {
OOR_LOG(LDBG_2, "UDP checksum failed.");
return (BAD);
}
}
OOR_LOG(LDBG_2, "%s, inner IP: %s -> %s, inner UDP: %d -> %d",
lisp_msg_hdr_to_char(pkt),
ip_to_char(&iph->ip_src, ip_version_to_sock_afi(iph->ip_v)),
ip_to_char(&iph->ip_dst, ip_version_to_sock_afi(iph->ip_v)),
ntohs(udph->source), ntohs(udph->dest));
return (GOOD);
}
/* Process a LISP protocol message sitting on
* socket s with address family afi */
int
vpnapi_control_dp_recv_msg(sock_t *sl)
{
uconn_t uc;
lbuf_t *b;
oor_ctrl_t *ctrl;
oor_ctrl_dev_t *dev;
ctrl = sl->arg;
/* Only one device supported for now */
dev = glist_first_data(ctrl->devices);
uc.lp = LISP_CONTROL_PORT;
b = lisp_msg_create_buf();
if (sock_ctrl_recv(sl->fd, b, &uc) != GOOD) {
OOR_LOG(LDBG_1, "Couldn't retrieve socket information"
"for control message! Discarding packet!");
lbuf_del(b);
return (BAD);
}
if (lbuf_size(b) < 4){
OOR_LOG(LDBG_3, "Received a non LISP message in the "
"control port! Discarding packet!");
return (BAD);
}
lbuf_reset_lisp(b);
OOR_LOG(LDBG_1, "Received %s, IP: %s -> %s, UDP: %d -> %d",
lisp_msg_hdr_to_char(b), lisp_addr_to_char(&uc.ra),
lisp_addr_to_char(&uc.la), uc.rp, uc.lp);
/* direct call of ctrl device
* TODO: check type to decide where to send msg*/
ctrl_dev_recv(dev, b, &uc);
lbuf_del(b);
return (GOOD);
}