1
2 /*
3 * Based upon 4.4BSD's /usr/sbin/arp
4 */
5 #include <sys/param.h>
6 #include <sys/file.h>
7 #include <sys/socket.h>
8 #include <sys/sysctl.h>
9 #include <net/if.h>
10 #include <net/if_dl.h>
11 #include <net/if_types.h>
12 # include <net/route.h>
13 #include <netinet/in.h>
14 #include <netinet/if_ether.h>
15 #include <arpa/inet.h>
16 #include <netinet/in.h>
17 #include <netinet/in_systm.h>
18 #include <netinet/ip.h>
19 #include <netinet/ip_var.h>
20 #include <netinet/tcp.h>
21 #include <unistd.h>
22 #include <string.h>
23 #include <stdlib.h>
24 #include <netdb.h>
25 #include <errno.h>
26 #include <nlist.h>
27 #include <stdio.h>
28 #include "ipsend.h"
29 #include "iplang/iplang.h"
30
31
32 /*
33 * lookup host and return
34 * its IP address in address
35 * (4 bytes)
36 */
resolve(char * host,char * address)37 int resolve(char *host, char *address)
38 {
39 struct hostent *hp;
40 u_long add;
41
42 add = inet_addr(host);
43 if (add == -1)
44 {
45 if (!(hp = gethostbyname(host)))
46 {
47 fprintf(stderr, "unknown host: %s\n", host);
48 return (-1);
49 }
50 bcopy((char *)hp->h_addr, (char *)address, 4);
51 return (0);
52 }
53 bcopy((char*)&add, address, 4);
54 return (0);
55 }
56
57
arp(char * addr,char * eaddr)58 int arp(char *addr, char *eaddr)
59 {
60 int mib[6];
61 size_t needed;
62 char *lim, *buf, *next;
63 struct rt_msghdr *rtm;
64 struct sockaddr_in *sin;
65 struct sockaddr_dl *sdl;
66
67 #ifdef IPSEND
68 if (arp_getipv4(addr, ether) == 0)
69 return (0);
70 #endif
71
72 if (!addr)
73 return (-1);
74
75 mib[0] = CTL_NET;
76 mib[1] = PF_ROUTE;
77 mib[2] = 0;
78 mib[3] = AF_INET;
79 mib[4] = NET_RT_FLAGS;
80 #ifdef RTF_LLINFO
81 mib[5] = RTF_LLINFO;
82 #else
83 mib[5] = 0;
84 #endif
85
86 if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
87 {
88 perror("route-sysctl-estimate");
89 exit(-1);
90 }
91 if ((buf = malloc(needed)) == NULL)
92 {
93 perror("malloc");
94 exit(-1);
95 }
96 if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1)
97 {
98 perror("actual retrieval of routing table");
99 exit(-1);
100 }
101 lim = buf + needed;
102 for (next = buf; next < lim; next += rtm->rtm_msglen)
103 {
104 rtm = (struct rt_msghdr *)next;
105 sin = (struct sockaddr_in *)(rtm + 1);
106 sdl = (struct sockaddr_dl *)(sin + 1);
107 if (!bcmp(addr, (char *)&sin->sin_addr,
108 sizeof(struct in_addr)))
109 {
110 bcopy(LLADDR(sdl), eaddr, sdl->sdl_alen);
111 return (0);
112 }
113 }
114 return (-1);
115 }
116