FreeBSD/sys/netinet/ip_ipsec.c
/*
 * Compute the MTU for a forwarded packet that gets IPSEC encapsulated.
 * Called from ip_forward().
 * Returns MTU suggestion for ICMP needfrag reply.
 */
Compute the MTU for a forwarded packet that gets IPSEC encapsulated.
Compute the MTU for a forwarded packet that gets IPSEC encapsulated .
int
ip_ipsec_mtu(struct mbuf *m, int mtu)
{
	return (mtu - ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL));
}
int ip_ipsec_mtu ( struct mbuf * m , int mtu ) { return ( mtu - ipsec_hdrsiz ( m , IPSEC_DIR_OUTBOUND , NULL ) ) ; }
Compute the MTU for a forwarded packet that gets IPSEC encapsulated.
Compute the MTU for a forwarded packet that gets IPSEC encapsulated .
/*
	 * If the packet is routed over IPsec tunnel, tell the
	 * originator the tunnel MTU.
	 *	tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
	 * XXX quickhack!!!
	 */