1 #ifdef HAVE_CONFIG_H
2 #include "config.h"
3 #endif
4
5 #include <stdlib.h>
6 #include <sys/types.h>
7 #include <sys/socket.h>
8 #include <netinet/in.h>
9 #include <arpa/inet.h>
10 #include <netdb.h>
11
12 #include <pcap.h>
13
14 static int ifprint(pcap_if_t *d);
15 static char *iptos(bpf_u_int32 in);
16
main(int argc,char ** argv)17 int main(int argc, char **argv)
18 {
19 pcap_if_t *alldevs;
20 pcap_if_t *d;
21 char *s;
22 bpf_u_int32 net, mask;
23 int exit_status = 0;
24
25 char errbuf[PCAP_ERRBUF_SIZE+1];
26 if (pcap_findalldevs(&alldevs, errbuf) == -1)
27 {
28 fprintf(stderr,"Error in pcap_findalldevs: %s\n",errbuf);
29 exit(1);
30 }
31 for(d=alldevs;d;d=d->next)
32 {
33 if (!ifprint(d))
34 exit_status = 2;
35 }
36
37 if ( (s = pcap_lookupdev(errbuf)) == NULL)
38 {
39 fprintf(stderr,"Error in pcap_lookupdev: %s\n",errbuf);
40 exit_status = 2;
41 }
42 else
43 {
44 printf("Preferred device name: %s\n",s);
45 }
46
47 if (pcap_lookupnet(s, &net, &mask, errbuf) < 0)
48 {
49 fprintf(stderr,"Error in pcap_lookupnet: %s\n",errbuf);
50 exit_status = 2;
51 }
52 else
53 {
54 printf("Preferred device is on network: %s/%s\n",iptos(net), iptos(mask));
55 }
56
57 exit(exit_status);
58 }
59
ifprint(pcap_if_t * d)60 static int ifprint(pcap_if_t *d)
61 {
62 pcap_addr_t *a;
63 #ifdef INET6
64 char ntop_buf[INET6_ADDRSTRLEN];
65 #endif
66 int status = 1; /* success */
67
68 printf("%s\n",d->name);
69 if (d->description)
70 printf("\tDescription: %s\n",d->description);
71 printf("\tLoopback: %s\n",(d->flags & PCAP_IF_LOOPBACK)?"yes":"no");
72
73 for(a=d->addresses;a;a=a->next) {
74 if (a->addr != NULL)
75 switch(a->addr->sa_family) {
76 case AF_INET:
77 printf("\tAddress Family: AF_INET\n");
78 if (a->addr)
79 printf("\t\tAddress: %s\n",
80 inet_ntoa(((struct sockaddr_in *)(a->addr))->sin_addr));
81 if (a->netmask)
82 printf("\t\tNetmask: %s\n",
83 inet_ntoa(((struct sockaddr_in *)(a->netmask))->sin_addr));
84 if (a->broadaddr)
85 printf("\t\tBroadcast Address: %s\n",
86 inet_ntoa(((struct sockaddr_in *)(a->broadaddr))->sin_addr));
87 if (a->dstaddr)
88 printf("\t\tDestination Address: %s\n",
89 inet_ntoa(((struct sockaddr_in *)(a->dstaddr))->sin_addr));
90 break;
91 #ifdef INET6
92 case AF_INET6:
93 printf("\tAddress Family: AF_INET6\n");
94 if (a->addr)
95 printf("\t\tAddress: %s\n",
96 inet_ntop(AF_INET6,
97 ((struct sockaddr_in6 *)(a->addr))->sin6_addr.s6_addr,
98 ntop_buf, sizeof ntop_buf));
99 if (a->netmask)
100 printf("\t\tNetmask: %s\n",
101 inet_ntop(AF_INET6,
102 ((struct sockaddr_in6 *)(a->netmask))->sin6_addr.s6_addr,
103 ntop_buf, sizeof ntop_buf));
104 if (a->broadaddr)
105 printf("\t\tBroadcast Address: %s\n",
106 inet_ntop(AF_INET6,
107 ((struct sockaddr_in6 *)(a->broadaddr))->sin6_addr.s6_addr,
108 ntop_buf, sizeof ntop_buf));
109 if (a->dstaddr)
110 printf("\t\tDestination Address: %s\n",
111 inet_ntop(AF_INET6,
112 ((struct sockaddr_in6 *)(a->dstaddr))->sin6_addr.s6_addr,
113 ntop_buf, sizeof ntop_buf));
114 break;
115 #endif
116 default:
117 printf("\tAddress Family: Unknown (%d)\n", a->addr->sa_family);
118 break;
119 }
120 else
121 {
122 fprintf(stderr, "\tWarning: a->addr is NULL, skipping this address.\n");
123 status = 0;
124 }
125 }
126 printf("\n");
127 return status;
128 }
129
130 /* From tcptraceroute */
131 #define IPTOSBUFFERS 12
iptos(bpf_u_int32 in)132 static char *iptos(bpf_u_int32 in)
133 {
134 static char output[IPTOSBUFFERS][3*4+3+1];
135 static short which;
136 u_char *p;
137
138 p = (u_char *)∈
139 which = (which + 1 == IPTOSBUFFERS ? 0 : which + 1);
140 sprintf(output[which], "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
141 return output[which];
142 }
143