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- Committer: Bazaar Package Importer
- Author(s): Noah Meyerhans
- Date: 2002-04-21 02:07:55 UTC
- Revision ID: james.westby@ubuntu.com-20020421020755-ttbj5lnh9l137vct
Tags: upstream-20020124
Import upstream version 20020124
- files added:
- Modules
- debian
- doc
- include-glibc
- include-glibc/bits
- include-glibc/bits/socket.h
- include-glibc/netinet
added
removed
arping.c
1
/*
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* arping.c
3
*
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* This program is free software; you can redistribute it and/or
5
* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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*/
11
12
#include <stdlib.h>
13
#include <sys/param.h>
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#include <sys/socket.h>
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#include <linux/sockios.h>
16
#include <sys/file.h>
17
#include <sys/time.h>
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#include <sys/signal.h>
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#include <sys/ioctl.h>
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#include <linux/if.h>
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#include <linux/if_arp.h>
22
#include <sys/uio.h>
23
24
#include <netdb.h>
25
#include <unistd.h>
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#include <stdio.h>
27
#include <ctype.h>
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#include <errno.h>
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#include <string.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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33
#include "SNAPSHOT.h"
34
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static void usage(void) __attribute__((noreturn));
36
37
int quit_on_reply=0;
38
char *device="eth0";
39
int ifindex;
40
char *source;
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struct in_addr src, dst;
42
char *target;
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int dad, unsolicited, advert;
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int quiet;
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int count=-1;
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int timeout;
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int unicasting;
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int s;
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int broadcast_only;
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struct sockaddr_ll me;
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struct sockaddr_ll he;
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struct timeval start, last;
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int sent, brd_sent;
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int received, brd_recv, req_recv;
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#define MS_TDIFF(tv1,tv2) ( ((tv1).tv_sec-(tv2).tv_sec)*1000 + \
60
((tv1).tv_usec-(tv2).tv_usec)/1000 )
61
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void usage(void)
63
{
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fprintf(stderr,
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"Usage: arping [-fqbDUAV] [-c count] [-w timeout] [-I device] [-s source] destination\n"
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" -f : quit on first reply\n"
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" -q : be quiet\n"
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" -b : keep broadcasting, don't go unicast\n"
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" -D : duplicate address detection mode\n"
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" -U : Unsolicited ARP mode, update your neighbours\n"
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" -A : ARP answer mode, update your neighbours\n"
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" -V : print version and exit\n"
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" -c count : how many packets to send\n"
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" -w timeout : how long to wait for a reply\n"
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" -I device : which ethernet device to use (eth0)\n"
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" -s source : source ip address\n"
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" destination : ask for what ip address\n"
78
);
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exit(2);
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}
81
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void set_signal(int signo, void (*handler)(void))
83
{
84
struct sigaction sa;
85
86
memset(&sa, 0, sizeof(sa));
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sa.sa_handler = (void (*)(int))handler;
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sa.sa_flags = SA_RESTART;
89
sigaction(signo, &sa, NULL);
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}
91
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int send_pack(int s, struct in_addr src, struct in_addr dst,
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struct sockaddr_ll *ME, struct sockaddr_ll *HE)
94
{
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int err;
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struct timeval now;
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unsigned char buf[256];
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struct arphdr *ah = (struct arphdr*)buf;
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unsigned char *p = (unsigned char *)(ah+1);
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ah->ar_hrd = htons(ME->sll_hatype);
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if (ah->ar_hrd == htons(ARPHRD_FDDI))
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ah->ar_hrd = htons(ARPHRD_ETHER);
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ah->ar_pro = htons(ETH_P_IP);
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ah->ar_hln = ME->sll_halen;
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ah->ar_pln = 4;
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ah->ar_op = advert ? htons(ARPOP_REPLY) : htons(ARPOP_REQUEST);
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memcpy(p, &ME->sll_addr, ah->ar_hln);
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p+=ME->sll_halen;
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memcpy(p, &src, 4);
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p+=4;
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if (advert)
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memcpy(p, &ME->sll_addr, ah->ar_hln);
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else
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memcpy(p, &HE->sll_addr, ah->ar_hln);
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p+=ah->ar_hln;
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121
memcpy(p, &dst, 4);
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p+=4;
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124
gettimeofday(&now, NULL);
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err = sendto(s, buf, p-buf, 0, (struct sockaddr*)HE, sizeof(*HE));
126
if (err == p-buf) {
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last = now;
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sent++;
129
if (!unicasting)
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brd_sent++;
131
}
132
return err;
133
}
134
135
void finish(void)
136
{
137
if (!quiet) {
138
printf("Sent %d probes (%d broadcast(s))\n", sent, brd_sent);
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printf("Received %d response(s)", received);
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if (brd_recv || req_recv) {
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printf(" (");
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if (req_recv)
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printf("%d request(s)", req_recv);
144
if (brd_recv)
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printf("%s%d broadcast(s)",
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req_recv ? ", " : "",
147
brd_recv);
148
printf(")");
149
}
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printf("\n");
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fflush(stdout);
152
}
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if (dad)
154
exit(!!received);
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if (unsolicited)
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exit(0);
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exit(!received);
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}
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void catcher(void)
161
{
162
struct timeval tv;
163
164
gettimeofday(&tv, NULL);
165
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if (start.tv_sec==0)
167
start = tv;
168
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if (count-- == 0 || (timeout && MS_TDIFF(tv,start) > timeout*1000 + 500))
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finish();
171
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if (last.tv_sec==0 || MS_TDIFF(tv,last) > 500) {
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send_pack(s, src, dst, &me, &he);
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if (count == 0 && unsolicited)
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finish();
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}
177
alarm(1);
178
}
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void print_hex(unsigned char *p, int len)
181
{
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int i;
183
for (i=0; i<len; i++) {
184
printf("%02X", p[i]);
185
if (i != len-1)
186
printf(":");
187
}
188
}
189
190
int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
191
{
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struct timeval tv;
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struct arphdr *ah = (struct arphdr*)buf;
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unsigned char *p = (unsigned char *)(ah+1);
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struct in_addr src_ip, dst_ip;
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gettimeofday(&tv, NULL);
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/* Filter out wild packets */
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if (FROM->sll_pkttype != PACKET_HOST &&
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FROM->sll_pkttype != PACKET_BROADCAST &&
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FROM->sll_pkttype != PACKET_MULTICAST)
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return 0;
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/* Only these types are recognised */
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if (ah->ar_op != htons(ARPOP_REQUEST) &&
207
ah->ar_op != htons(ARPOP_REPLY))
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return 0;
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/* ARPHRD check and this darned FDDI hack here :-( */
211
if (ah->ar_hrd != htons(FROM->sll_hatype) &&
212
(FROM->sll_hatype != ARPHRD_FDDI || ah->ar_hrd != htons(ARPHRD_ETHER)))
213
return 0;
214
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/* Protocol must be IP. */
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if (ah->ar_pro != htons(ETH_P_IP))
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return 0;
218
if (ah->ar_pln != 4)
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return 0;
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if (ah->ar_hln != me.sll_halen)
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return 0;
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if (len < sizeof(*ah) + 2*(4 + ah->ar_hln))
223
return 0;
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memcpy(&src_ip, p+ah->ar_hln, 4);
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memcpy(&dst_ip, p+ah->ar_hln+4+ah->ar_hln, 4);
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if (!dad) {
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if (src_ip.s_addr != dst.s_addr)
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return 0;
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if (src.s_addr != dst_ip.s_addr)
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return 0;
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if (memcmp(p+ah->ar_hln+4, &me.sll_addr, ah->ar_hln))
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return 0;
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} else {
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/* DAD packet was:
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src_ip = 0 (or some src)
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src_hw = ME
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dst_ip = tested address
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dst_hw = <unspec>
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We fail, if receive request/reply with:
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src_ip = tested_address
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src_hw != ME
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if src_ip in request was not zero, check
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also that it matches to dst_ip, otherwise
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dst_ip/dst_hw do not matter.
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*/
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if (src_ip.s_addr != dst.s_addr)
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return 0;
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if (memcmp(p, &me.sll_addr, me.sll_halen) == 0)
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return 0;
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if (src.s_addr && src.s_addr != dst_ip.s_addr)
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return 0;
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}
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if (!quiet) {
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int s_printed = 0;
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printf("%s ", FROM->sll_pkttype==PACKET_HOST ? "Unicast" : "Broadcast");
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printf("%s from ", ah->ar_op == htons(ARPOP_REPLY) ? "reply" : "request");
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printf("%s [", inet_ntoa(src_ip));
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print_hex(p, ah->ar_hln);
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printf("] ");
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if (dst_ip.s_addr != src.s_addr) {
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printf("for %s ", inet_ntoa(dst_ip));
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s_printed = 1;
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}
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if (memcmp(p+ah->ar_hln+4, me.sll_addr, ah->ar_hln)) {
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if (!s_printed)
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printf("for ");
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printf("[");
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print_hex(p+ah->ar_hln+4, ah->ar_hln);
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printf("]");
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}
272
if (last.tv_sec) {
273
long usecs = (tv.tv_sec-last.tv_sec) * 1000000 +
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tv.tv_usec-last.tv_usec;
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long msecs = (usecs+500)/1000;
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usecs -= msecs*1000 - 500;
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printf(" %ld.%03ldms\n", msecs, usecs);
278
} else {
279
printf(" UNSOLICITED?\n");
280
}
281
fflush(stdout);
282
}
283
received++;
284
if (FROM->sll_pkttype != PACKET_HOST)
285
brd_recv++;
286
if (ah->ar_op == htons(ARPOP_REQUEST))
287
req_recv++;
288
if (quit_on_reply)
289
finish();
290
if(!broadcast_only) {
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memcpy(he.sll_addr, p, me.sll_halen);
292
unicasting=1;
293
}
294
return 1;
295
}
296
297
int
298
main(int argc, char **argv)
299
{
300
int socket_errno;
301
int ch;
302
uid_t uid = getuid();
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s = socket(PF_PACKET, SOCK_DGRAM, 0);
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socket_errno = errno;
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307
setuid(uid);
308
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while ((ch = getopt(argc, argv, "h?bfDUAqc:w:s:I:V")) != EOF) {
310
switch(ch) {
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case 'b':
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broadcast_only=1;
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break;
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case 'D':
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dad++;
316
quit_on_reply=1;
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break;
318
case 'U':
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unsolicited++;
320
break;
321
case 'A':
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advert++;
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unsolicited++;
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break;
325
case 'q':
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quiet++;
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break;
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case 'c':
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count = atoi(optarg);
330
break;
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case 'w':
332
timeout = atoi(optarg);
333
break;
334
case 'I':
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device = optarg;
336
break;
337
case 'f':
338
quit_on_reply=1;
339
break;
340
case 's':
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source = optarg;
342
break;
343
case 'V':
344
printf("arping utility, iputils-ss%s\n", SNAPSHOT);
345
exit(0);
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case 'h':
347
case '?':
348
default:
349
usage();
350
}
351
}
352
argc -= optind;
353
argv += optind;
354
355
if (argc != 1)
356
usage();
357
358
target = *argv;
359
360
if (device == NULL) {
361
fprintf(stderr, "arping: device (option -I) is required\n");
362
usage();
363
}
364
365
if (s < 0) {
366
errno = socket_errno;
367
perror("arping: socket");
368
exit(2);
369
}
370
371
if (1) {
372
struct ifreq ifr;
373
memset(&ifr, 0, sizeof(ifr));
374
strncpy(ifr.ifr_name, device, IFNAMSIZ-1);
375
if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
376
fprintf(stderr, "arping: unknown iface %s\n", device);
377
exit(2);
378
}
379
ifindex = ifr.ifr_ifindex;
380
381
if (ioctl(s, SIOCGIFFLAGS, (char*)&ifr)) {
382
perror("ioctl(SIOCGIFFLAGS)");
383
exit(2);
384
}
385
if (!(ifr.ifr_flags&IFF_UP)) {
386
if (!quiet)
387
printf("Interface \"%s\" is down\n", device);
388
exit(2);
389
}
390
if (ifr.ifr_flags&(IFF_NOARP|IFF_LOOPBACK)) {
391
if (!quiet)
392
printf("Interface \"%s\" is not ARPable\n", device);
393
exit(dad?0:2);
394
}
395
}
396
397
if (inet_aton(target, &dst) != 1) {
398
struct hostent *hp;
399
hp = gethostbyname2(target, AF_INET);
400
if (!hp) {
401
fprintf(stderr, "arping: unknown host %s\n", target);
402
exit(2);
403
}
404
memcpy(&dst, hp->h_addr, 4);
405
}
406
407
if (source && inet_aton(source, &src) != 1) {
408
fprintf(stderr, "arping: invalid source %s\n", source);
409
exit(2);
410
}
411
412
if (!dad && unsolicited && src.s_addr == 0)
413
src = dst;
414
415
if (!dad || src.s_addr) {
416
struct sockaddr_in saddr;
417
int probe_fd = socket(AF_INET, SOCK_DGRAM, 0);
418
419
if (probe_fd < 0) {
420
perror("socket");
421
exit(2);
422
}
423
if (device) {
424
if (setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device)+1) == -1)
425
perror("WARNING: interface is ignored");
426
}
427
memset(&saddr, 0, sizeof(saddr));
428
saddr.sin_family = AF_INET;
429
if (src.s_addr) {
430
saddr.sin_addr = src;
431
if (bind(probe_fd, (struct sockaddr*)&saddr, sizeof(saddr)) == -1) {
432
perror("bind");
433
exit(2);
434
}
435
} else if (!dad) {
436
int on = 1;
437
int alen = sizeof(saddr);
438
439
saddr.sin_port = htons(1025);
440
saddr.sin_addr = dst;
441
442
if (setsockopt(probe_fd, SOL_SOCKET, SO_DONTROUTE, (char*)&on, sizeof(on)) == -1)
443
perror("WARNING: setsockopt(SO_DONTROUTE)");
444
if (connect(probe_fd, (struct sockaddr*)&saddr, sizeof(saddr)) == -1) {
445
perror("connect");
446
exit(2);
447
}
448
if (getsockname(probe_fd, (struct sockaddr*)&saddr, &alen) == -1) {
449
perror("getsockname");
450
exit(2);
451
}
452
src = saddr.sin_addr;
453
}
454
close(probe_fd);
455
};
456
457
me.sll_family = AF_PACKET;
458
me.sll_ifindex = ifindex;
459
me.sll_protocol = htons(ETH_P_ARP);
460
if (bind(s, (struct sockaddr*)&me, sizeof(me)) == -1) {
461
perror("bind");
462
exit(2);
463
}
464
465
if (1) {
466
int alen = sizeof(me);
467
if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
468
perror("getsockname");
469
exit(2);
470
}
471
}
472
if (me.sll_halen == 0) {
473
if (!quiet)
474
printf("Interface \"%s\" is not ARPable (no ll address)\n", device);
475
exit(dad?0:2);
476
}
477
478
he = me;
479
memset(he.sll_addr, -1, he.sll_halen);
480
481
if (!quiet) {
482
printf("ARPING %s ", inet_ntoa(dst));
483
printf("from %s %s\n", inet_ntoa(src), device ? : "");
484
}
485
486
if (!src.s_addr && !dad) {
487
fprintf(stderr, "arping: no source address in not-DAD mode\n");
488
exit(2);
489
}
490
491
set_signal(SIGINT, finish);
492
set_signal(SIGALRM, catcher);
493
494
catcher();
495
496
while(1) {
497
sigset_t sset, osset;
498
char packet[4096];
499
struct sockaddr_ll from;
500
int alen = sizeof(from);
501
int cc;
502
503
if ((cc = recvfrom(s, packet, sizeof(packet), 0,
504
(struct sockaddr *)&from, &alen)) < 0) {
505
perror("arping: recvfrom");
506
continue;
507
}
508
sigemptyset(&sset);
509
sigaddset(&sset, SIGALRM);
510
sigaddset(&sset, SIGINT);
511
sigprocmask(SIG_BLOCK, &sset, &osset);
512
recv_pack(packet, cc, &from);
513
sigprocmask(SIG_SETMASK, &osset, NULL);
514
}
515
}
516
517
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