headers.h

#ifndef HEADERS_H_
#include <netinet/in.h>
#define HEADERS_H_
#define ETHER_ADDR_LEN	6

#define DEF_DEV "wlan0"
#define DEF_F "icap"
/* Ethernet header */
struct ethernet_hdr {
	unsigned char ether_dhost[ETHER_ADDR_LEN]; /* Destination host address */
	unsigned char ether_shost[ETHER_ADDR_LEN]; /* Source host address */
	unsigned short ether_type; /* IP? ARP? RARP? etc */
};

	/* IP header */
struct ip_hdr {
	unsigned char ip_vhl;		/* version << 4 | header length >> 2 */
	unsigned char ip_tos;		/* type of service */
	unsigned short ip_len;		/* total length */
	unsigned short ip_id;		/* identification */
	unsigned short ip_off;		/* fragment offset field */
#define IP_RF 0x8000		/* reserved fragment flag */
#define IP_DF 0x4000		/* dont fragment flag */
#define IP_MF 0x2000		/* more fragments flag */
#define IP_OFFMASK 0x1fff	/* mask for fragmenting bits */
	unsigned char ip_ttl;		/* time to live */
	unsigned char ip_p;		/* protocol */
	unsigned short ip_sum;		/* checksum */
	unsigned int ip_src;
	unsigned int ip_dst; /* source and dest address */
};
#define IP_HL(ip)		(((ip)->ip_vhl) & 0x0f)
#define IP_V(ip)		(((ip)->ip_vhl) >> 4)

/* UDP header */
struct udp_hdr {
 unsigned short int uh_sport;
 unsigned short int uh_dport;
 unsigned short int uh_len;
 unsigned short int uh_chksum;
};

/* TCP header */
typedef unsigned int tcp_seq;

struct tcp_hdr {
	unsigned short th_sport;	/* source port */
	unsigned short th_dport;	/* destination port */
	tcp_seq th_seq;		/* sequence number */
	tcp_seq th_ack;		/* acknowledgement number */
	unsigned char th_offx2;	/* data offset, rsvd */
#define TH_OFF(th)	(((th)->th_offx2 & 0xf0) >> 4)
	unsigned char th_flags;
#define TH_FIN 0x01
#define TH_SYN 0x02
#define TH_RST 0x04
#define TH_PUSH 0x08
#define TH_ACK 0x10
#define TH_URG 0x20
#define TH_ECE 0x40
#define TH_CWR 0x80
#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG|TH_ECE|TH_CWR)
	unsigned short th_win;		/* window */
	unsigned short th_sum;		/* checksum */
	unsigned short th_urp;		/* urgent pointer */
};

/* CR: Use typedef here (And use _t in the name) */
typedef struct portlist
{
	unsigned short port;
	int cnt;
	struct portlist *next;
} portlist_t;
#endif