Ubuntu 10.10 Pcap

[eba]

Hi ,
I have problems with pcap.h. I have installed the libpcap ... but the problems are still there.
Can anyone help me thank you
Here is my code :

#define _BSD_SOURCE 1

#include <pcap.h>

#include <stdio.h>

#include <ctype.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include <net/if.h>

#include <netinet/if_ether.h>

#include "/home/moi/headers.h"

#define SNAP_LEN 1518

#define NB_PAQUETS 5

void callback(u_char *args, const struct _pkthdr *header,const u_char *packet)

{

static int count = 1;

const struct ethernet *ethernet; /* entete ethernet */

const struct ip *ip; /* entete IP */

const struct tcp *tcp; /* entete TCP */

const char *payload; /* payload */

int size_ethernet = 14;

int size_ip;

int size_tcp;

int size_payload;

printf("\nNombre de paquets captures [%d]\n", count);

count++;

ethernet = (struct ethernet*) (packet) ;

//Parametres de l'entete IP

ip = (struct ip*) (packet + size_ethernet);

size_ip = ip->ip_hlen*4;

printf ("IP source: [%s] --> IP Destination :[%s] ",inet_ntoa(ip->ip_source),inet_ntoa(ip->ip_dest));

//Parametres de l'entete TCP

tcp = (struct tcp*) (packet + size_ethernet + size_ip);

size_tcp = tcp->tcp_hlen*4;

printf("Port Source: [%d] --> Port Destination: [%d]\n", ntohs(tcp-> tcp_sourceport), ntohs(tcp->tcp_destport));

printf ("Drapaux : [FIN=%d] [SYN=%d] [RST=%d] [PSH=%d] [ACK=%d] [URG=%d] \n" , tcp->

tcp_fin,tcp->tcp_syn, tcp->tcp_rst, tcp->tcp_psh,tcp->tcp_ack,tcp->tcp_urg);

//Affichage de la partie donnee d'un paquet

payload = (u_char *) (packet + size_ethernet + size_ip + size_tcp);

size_payload = ntohs(ip->ip_total_length) - (size_ip + size_tcp);

printf ("Payload [%d bytes] [%s] ", size_payload, payload);

}

int main ()

{

char *dev = NULL; /* interface reseau */

char errbuf[PCAP_ERRBUF_SIZE]; /* buffer d'erreurs */

pcap_t *descr; /* descripteur de paquets */

struct bpf_program fp;

//char *packet=NULL;

bpf_u_int32 maskp; /* masque reseau */

bpf_u_int32 netp; /* adresse ip */

char filter_app[]= "tcp"; /* filtre * /





/* Etape 1 : detecter l'interface reseau */

dev = "wlan0"; //pcap_lookupdev(errbuf);



/* Etape 2 : recuperer les informations reseau */

pcap_lookupnet(dev, &netp, &maskp, errbuf);



/* Etape 3 : obtenir un descripteur de capture de paquets */

descr = pcap_open_live(dev, SNAP_LEN, 1, 0, errbuf);



/* Etape 4: compiler la configuration de capture choisie */

pcap_compile(descr, &fp, filter_app, 0, maskp);



/* Etape 5 : appliquer Ie filtre */

pcap_setfilter(descr, &fp);



/*Etape 6 : lancer la capture de paquets --> declenchement de la fonction a chaque

paquet recu */

pcap_loop(descr, NB_PAQUETS,callback, NULL);



/* Etape 7 : fermeture du descripteur de paquets */

pcap_close(descr) ;

return 0;

}

and here are the problems when i compile

main.c:12: warning: 'struct _pkthdr' declared inside parameter list
main.c: In function 'main':
main.c:70: warning: passing argument 3 of 'pcap_loop' from incompatible pointer type
/usr/include/pcap/pcap.h:297: note: expected 'pcap_handler' but argument is of type 'void (*)(u_char *, const struct _pkthdr *, const u_char *)'
/tmp/ccZcy8p7.o: In function `main':
main.c:(.text+0x225): undefined reference to `pcap_lookupnet'
main.c:(.text+0x251): undefined reference to `pcap_open_live'
main.c:(.text+0x281): undefined reference to `pcap_compile'
main.c:(.text+0x295): undefined reference to `pcap_setfilter'
main.c:(.text+0x2ba): undefined reference to `pcap_loop'
main.c:(.text+0x2c6): undefined reference to `pcap_close'
collect2: ld returned 1 exit status
}

Thank you very much for your help.
I'm waiting for you

[Rubberman]

Most of your errors are linkage errors. The rest are pretty much self-explanatory.

In your compilation output:
1. First line is a warning - you haven't defined or included the definition/declaration of "struck _pkthdr" before using it as an argument to a function definition.
2. Line 3 is a warning also - your use of pcap_loop() is inconsistent with the definition of the function in /usr/include/pcap.h.

Since these are only warnings, you might be able to build a functional program, but you haven't told your Makefile where to find the libraries and which libraries contain the implementation of pcap_lookupnet() et al.