packet.h

#ifndef PACKET_H
#define PACKET_H

#include<stdlib.h>
#include "tcp/http.h"
#include<netinet/in.h>
#include<pcap/pcap.h>
#include<arpa/inet.h>

/* Ethernet addresses are 6 bytes */
#define ETHER_ADDR_LEN  6
#define SIZE_ETHERNET 14

/* Ethernet header */ 
struct sniff_ethernet { 
  u_char  ether_dhost[ETHER_ADDR_LEN];    /* destination host address */ 
  u_char  ether_shost[ETHER_ADDR_LEN];    /* source host address */ 
  u_short ether_type;                     /* IP? ARP? RARP? etc */ 
}; 

/* IP header */ 
struct sniff_ip { 
  u_char  ip_vhl;                 /* version << 4 | header length >> 2 */ 
  u_char  ip_tos;                 /* type of service */ 
  u_short ip_len;                 /* total length */ 
  u_short ip_id;                  /* identification */ 
  u_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 */ 
  u_char  ip_ttl;                 /* time to live */ 
  u_char  ip_p;                   /* protocol */ 
  u_short ip_sum;                 /* checksum */ 
  struct  in_addr ip_src,ip_dst;  /* source and dest address */ 
}; 
#define IP_HL(ip)               (((ip)->ip_vhl) & 0x0f) 
#define IP_V(ip)                (((ip)->ip_vhl) >> 4) 

/* TCP header */ 
typedef u_int tcp_seq; 

struct sniff_tcp { 
  u_short th_sport;               /* source port */ 
  u_short th_dport;               /* destination port */ 
  tcp_seq th_seq;                 /* sequence number */ 
  tcp_seq th_ack;                 /* acknowledgement number */ 
  u_char  th_offx2;               /* data offset, rsvd */ 
  #define TH_OFF(th)      (((th)->th_offx2 & 0xf0) >> 4) 
  u_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) 
  u_short th_win;                 /* window */ 
  u_short th_sum;                 /* checksum */ 
  u_short th_urp;                 /* urgent pointer */ 
}; 

void got_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *packet);

#endif