1/* $NetBSD: 44arp.c,v 1.2 2016/04/04 07:37:07 ozaki-r Exp $ */
2
3/*
4 * Based upon 4.4BSD's /usr/sbin/arp
5 */
6#include <sys/param.h>
7#include <sys/file.h>
8#include <sys/socket.h>
9#include <sys/sysctl.h>
10#include <net/if.h>
11#if __FreeBSD_version >= 300000
12# include <net/if_var.h>
13#endif
14#include <net/if_dl.h>
15#include <net/if_types.h>
16#ifndef __osf__
17# include <net/route.h>
18#endif
19#include <netinet/in.h>
20#include <netinet/if_ether.h>
21#include <arpa/inet.h>
22#include <netinet/in.h>
23#include <netinet/in_systm.h>
24#include <netinet/ip.h>
25#include <netinet/ip_var.h>
26#include <netinet/tcp.h>
27#include <unistd.h>
28#include <string.h>
29#include <stdlib.h>
30#include <netdb.h>
31#include <errno.h>
32#include <nlist.h>
33#include <stdio.h>
34#include "ipsend.h"
35#include "iplang/iplang.h"
36
37
38/*
39 * lookup host and return
40 * its IP address in address
41 * (4 bytes)
42 */
43int resolve(host, address)
44 char *host, *address;
45{
46 struct hostent *hp;
47 u_long add;
48
49 add = inet_addr(host);
50 if (add == -1)
51 {
52 if (!(hp = gethostbyname(host)))
53 {
54 fprintf(stderr, "unknown host: %s\n", host);
55 return -1;
56 }
57 bcopy((char *)hp->h_addr, (char *)address, 4);
58 return 0;
59 }
60 bcopy((char*)&add, address, 4);
61 return 0;
62}
63
64
65int arp(addr, eaddr)
66 char *addr, *eaddr;
67{
68 int mib[6];
69 size_t needed;
70 char *lim, *buf, *next;
71 struct rt_msghdr *rtm;
72 struct sockaddr_inarp *sin;
73 struct sockaddr_dl *sdl;
74
75#ifdef IPSEND
76 if (arp_getipv4(addr, ether) == 0)
77 return 0;
78#endif
79
80 if (!addr)
81 return -1;
82
83 mib[0] = CTL_NET;
84 mib[1] = PF_ROUTE;
85 mib[2] = 0;
86 mib[3] = AF_INET;
87 mib[4] = NET_RT_FLAGS;
88#ifdef RTF_LLINFO
89 mib[5] = RTF_LLINFO;
90#else
91 mib[5] = 0;
92#endif
93 if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
94 {
95 perror("route-sysctl-estimate");
96 exit(-1);
97 }
98 if ((buf = malloc(needed)) == NULL)
99 {
100 perror("malloc");
101 exit(-1);
102 }
103 if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1)
104 {
105 perror("actual retrieval of routing table");
106 exit(-1);
107 }
108 lim = buf + needed;
109 for (next = buf; next < lim; next += rtm->rtm_msglen)
110 {
111 rtm = (struct rt_msghdr *)next;
112 sin = (struct sockaddr_inarp *)(rtm + 1);
113 sdl = (struct sockaddr_dl *)(sin + 1);
114 if (!bcmp(addr, (char *)&sin->sin_addr,
115 sizeof(struct in_addr)))
116 {
117 bcopy(LLADDR(sdl), eaddr, sdl->sdl_alen);
118 return 0;
119 }
120 }
121 return -1;
122}
123