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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <sys/types.h>
#ifdef _WIN32
#include <winsock2.h>
#else
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#endif
#include <pcap.h>
static int ifprint(pcap_if_t *d);
static char *iptos(bpf_u_int32 in);
int main(int argc, char **argv)
{
pcap_if_t *alldevs;
pcap_if_t *d;
char *s;
bpf_u_int32 net, mask;
int exit_status = 0;
char errbuf[PCAP_ERRBUF_SIZE+1];
if (pcap_findalldevs(&alldevs, errbuf) == -1)
{
fprintf(stderr,"Error in pcap_findalldevs: %s\n",errbuf);
exit(1);
}
for(d=alldevs;d;d=d->next)
{
if (!ifprint(d))
exit_status = 2;
}
if ( (s = pcap_lookupdev(errbuf)) == NULL)
{
fprintf(stderr,"Error in pcap_lookupdev: %s\n",errbuf);
exit_status = 2;
}
else
{
printf("Preferred device name: %s\n",s);
}
if (pcap_lookupnet(s, &net, &mask, errbuf) < 0)
{
fprintf(stderr,"Error in pcap_lookupnet: %s\n",errbuf);
exit_status = 2;
}
else
{
printf("Preferred device is on network: %s/%s\n",iptos(net), iptos(mask));
}
exit(exit_status);
}
static int ifprint(pcap_if_t *d)
{
pcap_addr_t *a;
#ifdef INET6
char ntop_buf[INET6_ADDRSTRLEN];
#endif
const char *sep;
int status = 1; /* success */
printf("%s\n",d->name);
if (d->description)
printf("\tDescription: %s\n",d->description);
printf("\tFlags: ");
sep = "";
if (d->flags & PCAP_IF_UP) {
printf("%sUP", sep);
sep = ", ";
}
if (d->flags & PCAP_IF_RUNNING) {
printf("%sRUNNING", sep);
sep = ", ";
}
if (d->flags & PCAP_IF_LOOPBACK) {
printf("%sLOOPBACK", sep);
sep = ", ";
}
printf("\n");
for(a=d->addresses;a;a=a->next) {
if (a->addr != NULL)
switch(a->addr->sa_family) {
case AF_INET:
printf("\tAddress Family: AF_INET\n");
if (a->addr)
printf("\t\tAddress: %s\n",
inet_ntoa(((struct sockaddr_in *)(a->addr))->sin_addr));
if (a->netmask)
printf("\t\tNetmask: %s\n",
inet_ntoa(((struct sockaddr_in *)(a->netmask))->sin_addr));
if (a->broadaddr)
printf("\t\tBroadcast Address: %s\n",
inet_ntoa(((struct sockaddr_in *)(a->broadaddr))->sin_addr));
if (a->dstaddr)
printf("\t\tDestination Address: %s\n",
inet_ntoa(((struct sockaddr_in *)(a->dstaddr))->sin_addr));
break;
#ifdef INET6
case AF_INET6:
printf("\tAddress Family: AF_INET6\n");
if (a->addr)
printf("\t\tAddress: %s\n",
inet_ntop(AF_INET6,
((struct sockaddr_in6 *)(a->addr))->sin6_addr.s6_addr,
ntop_buf, sizeof ntop_buf));
if (a->netmask)
printf("\t\tNetmask: %s\n",
inet_ntop(AF_INET6,
((struct sockaddr_in6 *)(a->netmask))->sin6_addr.s6_addr,
ntop_buf, sizeof ntop_buf));
if (a->broadaddr)
printf("\t\tBroadcast Address: %s\n",
inet_ntop(AF_INET6,
((struct sockaddr_in6 *)(a->broadaddr))->sin6_addr.s6_addr,
ntop_buf, sizeof ntop_buf));
if (a->dstaddr)
printf("\t\tDestination Address: %s\n",
inet_ntop(AF_INET6,
((struct sockaddr_in6 *)(a->dstaddr))->sin6_addr.s6_addr,
ntop_buf, sizeof ntop_buf));
break;
#endif
default:
printf("\tAddress Family: Unknown (%d)\n", a->addr->sa_family);
break;
}
else
{
fprintf(stderr, "\tWarning: a->addr is NULL, skipping this address.\n");
status = 0;
}
}
printf("\n");
return status;
}
/* From tcptraceroute */
#define IPTOSBUFFERS 12
static char *iptos(bpf_u_int32 in)
{
static char output[IPTOSBUFFERS][3*4+3+1];
static short which;
u_char *p;
p = (u_char *)∈
which = (which + 1 == IPTOSBUFFERS ? 0 : which + 1);
sprintf(output[which], "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
return output[which];
}
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