1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <pcap.h>
static void 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;
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)
{
ifprint(d);
}
if ( (s = pcap_lookupdev(errbuf)) == NULL)
{
fprintf(stderr,"Error in pcap_lookupdev: %s\n",errbuf);
}
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);
}
else
{
printf("Preferred device is on network: %s/%s\n",iptos(net), iptos(mask));
}
exit(0);
}
static void ifprint(pcap_if_t *d)
{
pcap_addr_t *a;
#ifdef INET6
char ntop_buf[INET6_ADDRSTRLEN];
#endif
printf("%s\n",d->name);
if (d->description)
printf("\tDescription: %s\n",d->description);
printf("\tLoopback: %s\n",(d->flags & PCAP_IF_LOOPBACK)?"yes":"no");
for(a=d->addresses;a;a=a->next) {
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;
}
}
printf("\n");
}
/* 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];
}
|
