busybox/ping.c
Erik Andersen 5cbdd712f5 mount and umount could leak loop device allocations causing the system to
quickly run out.  Also disable init's SIGHUP handler during shutdown.
 -Erik
2000-01-26 20:06:48 +00:00

455 lines
13 KiB
C

/*
* $Id: ping.c,v 1.7 2000/01/26 20:06:48 erik Exp $
* Mini ping implementation for busybox
*
* Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This version of ping is adapted from the ping in netkit-base 0.10,
* which is:
*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Mike Muuss.
*
* Original copyright notice is retained at the end of this file.
*/
#include "internal.h"
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/times.h>
#include <sys/signal.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#define DEFDATALEN 56
#define MAXIPLEN 60
#define MAXICMPLEN 76
#define MAXPACKET 65468
#define MAX_DUP_CHK (8 * 128)
#define MAXWAIT 10
#define PINGINTERVAL 1 /* second */
#define O_QUIET (1 << 0)
#define A(bit) rcvd_tbl[(bit)>>3] /* identify byte in array */
#define B(bit) (1 << ((bit) & 0x07)) /* identify bit in byte */
#define SET(bit) (A(bit) |= B(bit))
#define CLR(bit) (A(bit) &= (~B(bit)))
#define TST(bit) (A(bit) & B(bit))
/* common routines */
static int in_cksum(unsigned short *buf, int sz)
{
int nleft = sz;
int sum = 0;
unsigned short *w = buf;
unsigned short ans = 0;
while (nleft > 1) {
sum += *w++;
nleft -= 2;
}
if (nleft == 1) {
*(unsigned char *)(&ans) = *(unsigned char *)w;
sum += ans;
}
sum = (sum >> 16) + (sum & 0xFFFF);
sum += (sum >> 16);
ans = ~sum;
return(ans);
}
/* simple version */
#ifdef BB_SIMPLE_PING
static const char* ping_usage = "ping host\n\n";
static char* hostname = NULL;
static void noresp(int ign)
{
printf("No response from %s\n", hostname);
exit(0);
}
static int ping(const char *host)
{
struct hostent *h;
struct sockaddr_in pingaddr;
struct icmp *pkt;
int pingsock, c;
char packet[DEFDATALEN + MAXIPLEN + MAXICMPLEN];
if ((pingsock = socket(AF_INET, SOCK_RAW, 1)) < 0) { /* 1 == ICMP */
perror("ping");
exit(1);
}
/* drop root privs if running setuid */
setuid(getuid());
memset(&pingaddr, 0, sizeof(struct sockaddr_in));
pingaddr.sin_family = AF_INET;
if (!(h = gethostbyname(host))) {
fprintf(stderr, "ping: unknown host %s\n", host);
exit(1);
}
memcpy(&pingaddr.sin_addr, h->h_addr, sizeof(pingaddr.sin_addr));
hostname = h->h_name;
pkt = (struct icmp *)packet;
memset(pkt, 0, sizeof(packet));
pkt->icmp_type = ICMP_ECHO;
pkt->icmp_cksum = in_cksum((unsigned short *)pkt, sizeof(packet));
c = sendto(pingsock, packet, sizeof(packet), 0,
(struct sockaddr *)&pingaddr, sizeof(struct sockaddr_in));
if (c < 0 || c != sizeof(packet)) {
if (c < 0) perror("ping");
fprintf(stderr, "ping: write incomplete\n");
exit(1);
}
signal(SIGALRM, noresp);
alarm(5); /* give the host 5000ms to respond */
/* listen for replies */
while (1) {
struct sockaddr_in from;
size_t fromlen = sizeof(from);
if ((c = recvfrom(pingsock, packet, sizeof(packet), 0,
(struct sockaddr *)&from, &fromlen)) < 0) {
if (errno == EINTR) continue;
perror("ping");
continue;
}
if (c >= 76) { /* ip + icmp */
struct iphdr *iphdr = (struct iphdr *)packet;
pkt = (struct icmp *)(packet + (iphdr->ihl << 2)); /* skip ip hdr */
if (pkt->icmp_type == ICMP_ECHOREPLY) break;
}
}
printf("%s is alive!\n", hostname);
return(TRUE);
}
extern int ping_main(int argc, char **argv)
{
argc--;
argv++;
if (argc < 1) usage(ping_usage);
ping(*argv);
exit(TRUE);
}
#else
/* full(er) version */
static const char* ping_usage = "ping [OPTION]... host\n\n"
"Send ICMP ECHO_REQUEST packets to network hosts.\n\n"
"Options:\n"
"\t-q\t\tQuiet mode, only displays output at start and when finished.\n"
"\t-c COUNT\tSend only COUNT pings.\n";
static char *hostname = NULL;
static struct sockaddr_in pingaddr;
static int pingsock = -1;
static long ntransmitted = 0, nreceived = 0, nrepeats = 0, pingcount = 0;
static int myid = 0, options = 0;
static unsigned long tmin = ULONG_MAX, tmax = 0, tsum = 0;
static char rcvd_tbl[MAX_DUP_CHK / 8];
static void sendping(int);
static void pingstats(int);
static void unpack(char *, int, struct sockaddr_in *);
static void ping(char *);
/**************************************************************************/
static void pingstats(int ign) {
signal(SIGINT, SIG_IGN);
printf("\n--- %s ping statistics ---\n", hostname);
printf("%ld packets transmitted, ", ntransmitted);
printf("%ld packets received, ", nreceived);
if (nrepeats)
printf("%ld duplicates, ", nrepeats);
if (ntransmitted)
printf("%ld%% packet loss\n",
(ntransmitted - nreceived)*100/ntransmitted);
if (nreceived)
printf("round-trip min/avg/max = %lu.%lu/%lu.%lu/%lu.%lu ms\n",
tmin/10, tmin%10,
(tsum/(nreceived+nrepeats))/10,
(tsum/(nreceived+nrepeats))%10,
tmax/10, tmax%10);
exit(0);
}
static void sendping(int ign)
{
struct icmp *pkt;
int i;
char packet[DEFDATALEN + 8];
pkt = (struct icmp *)packet;
pkt->icmp_type = ICMP_ECHO;
pkt->icmp_code = 0;
pkt->icmp_cksum = 0;
pkt->icmp_seq = ntransmitted++;
pkt->icmp_id = myid;
CLR(pkt->icmp_seq % MAX_DUP_CHK);
gettimeofday((struct timeval *)&packet[8], NULL);
pkt->icmp_cksum = in_cksum((unsigned short *)pkt, sizeof(packet));
i = sendto(pingsock, packet, sizeof(packet), 0,
(struct sockaddr *)&pingaddr, sizeof(struct sockaddr_in));
if (i < 0 || i != sizeof(packet)) {
if (i < 0) perror("ping");
fprintf(stderr, "ping wrote %d chars; %d expected\n", i, sizeof(packet));
exit(1);
}
signal(SIGALRM, sendping);
if (pingcount == 0 || ntransmitted < pingcount) { /* schedule next in 1s */
alarm(PINGINTERVAL);
} else { /* done, wait for the last ping to come back */
/* todo, don't necessarily need to wait so long... */
signal(SIGALRM, pingstats);
alarm(MAXWAIT);
}
}
static void unpack(char *buf, int sz, struct sockaddr_in *from)
{
struct icmp *icmppkt;
struct iphdr *iphdr;
struct timeval tv, *tp;
int hlen, dupflag;
unsigned long triptime;
gettimeofday(&tv, NULL);
/* check IP header */
iphdr = (struct iphdr *)buf;
hlen = iphdr->ihl << 2;
/* discard if too short */
if (sz < (DEFDATALEN + ICMP_MINLEN)) return;
sz -= hlen;
icmppkt = (struct icmp *)(buf + hlen);
if (icmppkt->icmp_type == ICMP_ECHOREPLY) {
if (icmppkt->icmp_id != myid) return; /* not our ping */
++nreceived;
tp = (struct timeval *)icmppkt->icmp_data;
if ((tv.tv_usec -= tp->tv_usec) < 0) {
--tv.tv_sec;
tv.tv_usec += 1000000;
}
tv.tv_sec -= tp->tv_sec;
triptime = tv.tv_sec * 10000 + (tv.tv_usec / 100);
tsum += triptime;
if (triptime < tmin) tmin = triptime;
if (triptime > tmax) tmax = triptime;
if (TST(icmppkt->icmp_seq % MAX_DUP_CHK)) {
++nrepeats;
--nreceived;
dupflag = 1;
} else {
SET(icmppkt->icmp_seq % MAX_DUP_CHK);
dupflag = 0;
}
if (options & O_QUIET) return;
printf("%d bytes from %s: icmp_seq=%u", sz,
inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr),
icmppkt->icmp_seq);
printf(" ttl=%d", iphdr->ttl);
printf(" time=%lu.%lu ms", triptime/10, triptime%10);
if (dupflag) printf(" (DUP!)");
printf("\n");
} else {
fprintf(stderr, "Warning: unknown ICMP packet received (not echo-reply)\n");
}
}
static void ping(char *host)
{
struct protoent *proto;
struct hostent *h;
char buf[MAXHOSTNAMELEN];
char packet[DEFDATALEN + MAXIPLEN + MAXICMPLEN];
int sockopt;
if (!(proto = getprotobyname("icmp"))) {
/* getprotobyname failed, so just silently force
* proto->p_proto to have the correct value for "icmp" */
proto->p_proto = 1;
}
if ((pingsock = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0) { /* 1 == ICMP */
if (errno == EPERM) {
fprintf(stderr, "ping: permission denied. (are you root?)\n");
} else {
perror("ping");
}
exit(1);
}
/* drop root privs if running setuid */
setuid(getuid());
memset(&pingaddr, 0, sizeof(struct sockaddr_in));
pingaddr.sin_family = AF_INET;
if (!(h = gethostbyname(host))) {
fprintf(stderr, "ping: unknown host %s\n", host);
exit(1);
}
if (h->h_addrtype != AF_INET) {
fprintf(stderr, "ping: unknown address type; only AF_INET is currently supported.\n");
exit(1);
}
pingaddr.sin_family = AF_INET; /* h->h_addrtype */
memcpy(&pingaddr.sin_addr, h->h_addr, sizeof(pingaddr.sin_addr));
strncpy(buf, h->h_name, sizeof(buf)-1);
hostname = buf;
/* enable broadcast pings */
sockopt = 1;
setsockopt(pingsock, SOL_SOCKET, SO_BROADCAST, (char *)&sockopt, sizeof(sockopt));
/* set recv buf for broadcast pings */
sockopt = 48 * 1024;
setsockopt(pingsock, SOL_SOCKET, SO_RCVBUF, (char *)&sockopt, sizeof(sockopt));
printf("PING %s (%s): %d data bytes\n",
hostname, inet_ntoa(*(struct in_addr *)&pingaddr.sin_addr.s_addr),
DEFDATALEN);
signal(SIGINT, pingstats);
/* start the ping's going ... */
sendping(0);
/* listen for replies */
while (1) {
struct sockaddr_in from;
size_t fromlen = sizeof(from);
int c;
if ((c = recvfrom(pingsock, packet, sizeof(packet), 0,
(struct sockaddr *)&from, &fromlen)) < 0) {
if (errno == EINTR) continue;
perror("ping");
continue;
}
unpack(packet, c, &from);
if (pingcount > 0 && nreceived >= pingcount) break;
}
pingstats(0);
}
extern int ping_main(int argc, char **argv)
{
char *thisarg;
argc--;
argv++;
options = 0;
/* Parse any options */
while (argc > 1) {
if (**argv != '-') usage(ping_usage);
thisarg = *argv; thisarg++;
switch (*thisarg) {
case 'q': options |= O_QUIET; break;
case 'c':
argc--; argv++;
pingcount = atoi(*argv);
break;
default:
usage(ping_usage);
}
argc--; argv++;
}
if (argc < 1) usage(ping_usage);
myid = getpid() & 0xFFFF;
ping(*argv);
exit(TRUE);
}
#endif
/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Mike Muuss.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/