minix3/commands/arp/arp.c

474 lines
9.1 KiB
C

/*
arp.c
Created: Jan 2001 by Philip Homburg <philip@f-mnx.phicoh.com>
Manipulate ARP table
*/
#define _POSIX_C_SOURCE 2
#define _NETBSD_SOURCE 1
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <net/netlib.h>
#include <net/gen/ether.h>
#include <net/gen/if_ether.h>
#include <net/gen/in.h>
#include <net/gen/inet.h>
#include <net/gen/ip_io.h>
#include <netdb.h>
#include <net/gen/socket.h>
#include <net/gen/arp_io.h>
char *progname;
static int ipfd= -1;
static int do_setuid= 0;
static void do_open(char *devname);
static void show_one(char *hostname, int do_num);
static void show_all(int do_num);
static void print_one(ipaddr_t ipaddr, nwio_arp_t *arpp, int do_num);
static void delete_all(void);
static void delete(char *hostname);
static void do_set(char *hostname, char *ethername, int temp, int pub,
int optdelete);
static ipaddr_t nametoipaddr(char *hostname);
static void fatal(const char *fmt, ...);
static void usage(void);
int main(int argc, char *argv[])
{
int c;
char *hostname, *ethername;
int do_temp, do_pub;
int a_flag, d_flag, n_flag, s_flag, S_flag;
char *I_arg;
(progname=strrchr(argv[0],'/')) ? progname++ : (progname=argv[0]);
a_flag= d_flag= n_flag= s_flag= S_flag= 0;
I_arg= NULL;
while(c= getopt(argc, argv, "adnsS?I:"), c != -1)
{
switch(c)
{
case '?': usage();
case 'a': a_flag= 1; break;
case 'd': d_flag= 1; break;
case 'n': n_flag= 1; break;
case 's': s_flag= 1; break;
case 'S': S_flag= 1; break;
case 'I': I_arg= optarg; break;
default: fatal("getopt failed: '%c'", c);
}
}
hostname= NULL; /* lint */
ethername= NULL; /* lint */
do_temp= do_pub= 0; /* lint */
if (n_flag + d_flag + s_flag + S_flag > 1)
usage();
if (s_flag || S_flag)
{
if (optind >= argc) usage();
hostname= argv[optind++];
if (optind >= argc) usage();
ethername= argv[optind++];
do_temp= do_pub= 0;
while (optind < argc)
{
if (strcasecmp(argv[optind], "temp") == 0)
{
do_temp= 1;
optind++;
continue;
}
if (strcasecmp(argv[optind], "pub") == 0)
{
do_pub= 1;
optind++;
continue;
}
usage();
}
}
else if (d_flag)
{
if (!a_flag)
{
if (optind >= argc)
usage();
hostname= argv[optind++];
if (optind != argc)
usage();
}
}
else if (a_flag)
{
if (optind != argc)
usage();
do_setuid= 1;
}
else
{
if (optind >= argc)
usage();
hostname= argv[optind++];
if (optind != argc)
usage();
do_setuid= 1;
}
do_open(I_arg);
if (d_flag)
{
if (a_flag)
delete_all();
else
delete(hostname);
}
else if (s_flag || S_flag)
do_set(hostname, ethername, do_temp, do_pub, S_flag);
else if (a_flag)
show_all(n_flag);
else
show_one(hostname, n_flag);
exit(0);
}
static void do_open(char *devname)
{
size_t l;
char *check;
if (do_setuid && devname)
{
/* Only strings that consist of IP_DEVICE optionally
* followed by a number are allowed.
*/
l= strlen(IP_DEVICE);
if (strncmp(devname, IP_DEVICE, l) != 0)
do_setuid= 0;
else if (strlen(devname) == l)
; /* OK */
else
{
strtoul(devname+l, &check, 10);
if (check[0] != '\0')
do_setuid= 0;
}
}
if (!devname)
devname= IP_DEVICE;
if (!do_setuid)
{
setuid(getuid());
setgid(getgid());
}
ipfd= open(devname, O_RDWR);
if (ipfd == -1)
fatal("unable to open '%s': %s", devname, strerror(errno));
}
static void show_one(char *hostname, int do_num)
{
int r;
ipaddr_t ipaddr;
nwio_arp_t arp;
ipaddr= nametoipaddr(hostname);
arp.nwa_ipaddr= ipaddr;
r= ioctl(ipfd, NWIOARPGIP, &arp);
if (r == -1 && errno == ENOENT)
{
print_one(ipaddr, NULL, do_num);
exit(1);
}
if (r == -1)
fatal("NWIOARPGIP failed: %s", strerror(errno));
print_one(ipaddr, &arp, do_num);
}
static void show_all(int do_num)
{
int ind, max, i, r;
nwio_arp_t *arptab;
nwio_arp_t arp;
/* First get all entries */
max= 10;
ind= 0;
arptab= malloc(max * sizeof(*arptab));
if (arptab == NULL)
{
fatal("out of memory, can't get %d bytes",
max*sizeof(*arptab));
}
arp.nwa_entno= 0;
for (;;)
{
if (ind == max)
{
max *= 2;
arptab= realloc(arptab, max * sizeof(*arptab));
if (!arptab)
{
fatal("out of memory, can't get %d bytes",
max*sizeof(*arptab));
}
}
r= ioctl(ipfd, NWIOARPGNEXT, &arp);
if (r == -1 && errno == ENOENT)
break;
if (r == -1)
fatal("NWIOARPGNEXT failed: %s", strerror(errno));
arptab[ind]= arp;
ind++;
}
for (i= 0; i<ind; i++)
print_one(0, &arptab[i], do_num);
}
static void print_one(ipaddr_t ipaddr, nwio_arp_t *arpp, int do_num)
{
u32_t flags;
struct hostent *he;
if (arpp)
ipaddr= arpp->nwa_ipaddr;
if (!do_num)
he= gethostbyaddr((char *)&ipaddr, sizeof(ipaddr), AF_INET);
else
he= NULL;
if (he)
printf("%s (%s)", he->h_name, inet_ntoa(ipaddr));
else
printf("%s", inet_ntoa(ipaddr));
if (!arpp)
{
printf(" -- no entry\n");
return;
}
flags= arpp->nwa_flags;
if (flags & NWAF_INCOMPLETE)
printf(" is incomplete");
else if (flags & NWAF_DEAD)
printf(" is dead");
else
{
printf(" is at %s", ether_ntoa(&arpp->nwa_ethaddr));
if (flags & NWAF_PERM)
printf(" permanent");
if (flags & NWAF_PUB)
printf(" published");
}
printf("\n");
}
static void delete_all(void)
{
int ind, max, i, r;
nwio_arp_t *arptab;
nwio_arp_t arp;
/* First get all entries */
max= 10;
ind= 0;
arptab= malloc(max * sizeof(*arptab));
if (arptab == NULL)
{
fatal("out of memory, can't get %d bytes",
max*sizeof(*arptab));
}
arp.nwa_entno= 0;
for (;;)
{
if (ind == max)
{
max *= 2;
arptab= realloc(arptab, max * sizeof(*arptab));
if (arptab == NULL)
{
fatal("out of memory, can't get %d bytes",
max*sizeof(*arptab));
}
}
r= ioctl(ipfd, NWIOARPGNEXT, &arp);
if (r == -1 && errno == ENOENT)
break;
if (r == -1)
fatal("NWIOARPGNEXT failed: %s", strerror(errno));
arptab[ind]= arp;
ind++;
}
for (i= 0; i<ind; i++)
{
r= ioctl(ipfd, NWIOARPDIP, &arptab[i]);
if (r == 0)
continue;
if (errno == EINVAL || errno == ENOENT)
{
/* Entry is incomplete of entry is already deleted */
continue;
}
fatal("unable to delete host %s: %s",
inet_ntoa(arptab[i].nwa_ipaddr), strerror(errno));
}
}
static void delete(char *hostname)
{
int r;
ipaddr_t ipaddr;
nwio_arp_t arp;
ipaddr= nametoipaddr(hostname);
arp.nwa_ipaddr= ipaddr;
r= ioctl(ipfd, NWIOARPDIP, &arp);
if (r == 0)
return;
if (errno == ENOENT)
{
print_one(ipaddr, NULL, 0);
exit(1);
}
fatal("unable to delete host %s: %s", inet_ntoa(ipaddr),
errno == EINVAL ? "entry is incomplete" : strerror(errno));
}
static void do_set(char *hostname, char *ethername, int temp, int pub,
int optdelete)
{
int r;
ipaddr_t ipaddr;
ether_addr_t *eap;
ether_addr_t ethaddr;
nwio_arp_t arp;
nwio_ipconf_t ipconf;
ipaddr= nametoipaddr(hostname);
if (pub && strcasecmp(ethername, "auto") == 0)
{
r= ioctl(ipfd, NWIOGIPCONF, &ipconf);
if (r == -1)
fatal("NWIOGIPCONF failed: %s", strerror(errno));
arp.nwa_ipaddr= ipconf.nwic_ipaddr;
r= ioctl(ipfd, NWIOARPGIP, &arp);
if (r == -1)
fatal("NWIOARPGIP failed: %s", strerror(errno));
ethaddr= arp.nwa_ethaddr;
}
else if (eap= ether_aton(ethername), eap != NULL)
ethaddr= *eap;
else if (ether_hostton(ethername, &ethaddr) != 0)
{
fatal("unable to parse ethernet address '%s'",
ethername);
}
if (optdelete)
{
arp.nwa_ipaddr= ipaddr;
r= ioctl(ipfd, NWIOARPDIP, &arp);
if (r == -1 && errno != ENOENT)
{
fatal("unable to delete entry for host %s: %s",
inet_ntoa(ipaddr),
errno == EINVAL ? "incomplete entry" :
strerror(errno));
}
}
arp.nwa_ipaddr= ipaddr;
arp.nwa_ethaddr= ethaddr;
arp.nwa_flags= 0;
if (pub)
arp.nwa_flags |= NWAF_PUB;
if (!temp)
arp.nwa_flags |= NWAF_PERM;
r= ioctl(ipfd, NWIOARPSIP, &arp);
if (r == -1)
{
fatal("unable to set arp entry: %s",
errno == EEXIST ? "entry exists" : strerror(errno));
}
}
static ipaddr_t nametoipaddr(char *hostname)
{
ipaddr_t ipaddr;
struct hostent *he;
if (inet_aton(hostname, &ipaddr) == 0)
{
he= gethostbyname(hostname);
if (!he)
fatal("unknown hostname '%s'", hostname);
if (he->h_addrtype != AF_INET ||
he->h_length != sizeof(ipaddr))
{
fatal("strange host '%s': addrtype %d, length %d",
he->h_addrtype, he->h_length);
}
memcpy(&ipaddr, he->h_addr, sizeof(ipaddr));
}
return ipaddr;
}
#if 0
static char *ether_ntoa(struct ether_addr *eap)
{
static char buf[]= "xx:xx:xx:xx:xx:xx";
sprintf(buf, "%02x:%02x:%02x:%02x:%02x:%02x",
eap->ea_addr[0], eap->ea_addr[1],
eap->ea_addr[2], eap->ea_addr[3],
eap->ea_addr[4], eap->ea_addr[5]);
return buf;
}
#endif
static void fatal(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
fprintf(stderr, "%s: ", progname);
vfprintf(stderr, fmt, ap);
fprintf(stderr, "\n");
va_end(ap);
exit(1);
}
static void usage(void)
{
fprintf(stderr, "Usage:\tarp [-I ip-dev] [-n] hostname\n"
"\tarp [-I ip-dev] [-n] -a\n"
"\tarp [-I ip-dev] -d hostname\n"
"\tarp [-I ip-dev] -d -a\n"
"\tarp [-I ip-dev] -s hostname ether-addr [temp] [pub]\n"
"\tarp [-I ip-dev] -S hostname ether-addr [temp] [pub]\n");
exit(1);
}
/*
* $PchId: arp.c,v 1.3 2005/01/31 22:31:45 philip Exp $
*/