{Open-source interface} libpcap interface for obtaining data packets in Linux/Windows

# Include <stdio. h>

# Include <pcap. h>

Typedef struct mac_header

{

Unsigned char d [6];

Unsigned char s [6];

Unsigned short type;

} Mac_header;

Void packet_handler (u_char * Param, const struct pcap_pkthdr * Header, const u_char * pkt_data );

Int main (INT argc, char * argv [])

{

Char * device;

Char errbuf [pcap_errbuf_size];

Pcap_t * P;

Device = pcap_lookupdev (errbuf );

P = pcap_open_live (device, 65536,1, 1000, errbuf );

Pcap_loop (p, 0, packet_handler, null );

Return (0 );

}

Void packet_handler (u_char * Param, const struct pcap_pkthdr * Header, const u_char * pkt_data)

{

Int I;

Mac_header * mac_header;

Mac_header = (mac_header *) pkt_data;

If (mac_header-> type = 0x0608)

{

Printf ("pppoe ARP \ n ");

For (I = 0; I <6; I ++)

Printf ("% 02x", pkt_data [I]);

Putchar ('\ n ');

For (I = 6; I <12; I ++)

Printf ("% 02x", pkt_data [I]);

Putchar ('\ n ');

}

}