+struct arp_eth_header
+{
+ __be16 ar_hrd; /* format of hardware address */
+ __be16 ar_pro; /* format of protocol address */
+ unsigned char ar_hln; /* length of hardware address */
+ unsigned char ar_pln; /* length of protocol address */
+ __be16 ar_op; /* ARP opcode (command) */
+
+ /* Ethernet+IPv4 specific members. */
+ unsigned char ar_sha[ETH_ALEN]; /* sender hardware address */
+ unsigned char ar_sip[4]; /* sender IP address */
+ unsigned char ar_tha[ETH_ALEN]; /* target hardware address */
+ unsigned char ar_tip[4]; /* target IP address */
+} __packed;
+
+int flow_init(void);
+void flow_exit(void);