summaryrefslogtreecommitdiffstats
path: root/usr.sbin/arp
diff options
context:
space:
mode:
authorphk <phk@FreeBSD.org>1996-02-08 21:05:52 +0000
committerphk <phk@FreeBSD.org>1996-02-08 21:05:52 +0000
commit329ca3c57c33c4266ee9b221159b11e9980fd242 (patch)
treeebe2bef9cf8996f80af250458b9dfe3ba69141b4 /usr.sbin/arp
parenta5442098738be2631eb0fbc49414a100ba9f894f (diff)
downloadFreeBSD-src-329ca3c57c33c4266ee9b221159b11e9980fd242.zip
FreeBSD-src-329ca3c57c33c4266ee9b221159b11e9980fd242.tar.gz
Clean up warnings.
fix return/exit codes in some cases. Add -S which will delete any old entry first. Add "auto" in proxy case, so it finds the right interface automatically.
Diffstat (limited to 'usr.sbin/arp')
-rw-r--r--usr.sbin/arp/arp.812
-rw-r--r--usr.sbin/arp/arp.c201
2 files changed, 178 insertions, 35 deletions
diff --git a/usr.sbin/arp/arp.8 b/usr.sbin/arp/arp.8
index 51fa68c..19bafed 100644
--- a/usr.sbin/arp/arp.8
+++ b/usr.sbin/arp/arp.8
@@ -49,6 +49,10 @@
.Op Ar temp
.Op Ar pub
.Nm arp
+.Fl S Ar hostname ether_addr
+.Op Ar temp
+.Op Ar pub
+.Nm arp
.Fl f Ar filename
.Sh DESCRIPTION
The
@@ -95,6 +99,14 @@ server,
responding to requests for
.Ar hostname
even though the host address is not its own.
+In this case the ether_addr can be given as `auto''
+in which case the interfaces on this host will be examined,
+and if one of them is found to occupy the same subnet, its
+ether_addr will be used.
+.It Fl S Ar hostname ether_addr
+Is just like
+.Fl s
+except any existing arp entry for this host will be deleted first.
.It Fl f
Causes the file
.Ar filename
diff --git a/usr.sbin/arp/arp.c b/usr.sbin/arp/arp.c
index 1eb718a..218f43a 100644
--- a/usr.sbin/arp/arp.c
+++ b/usr.sbin/arp/arp.c
@@ -35,13 +35,14 @@
*/
#ifndef lint
-static char copyright[] =
+static char const copyright[] =
"@(#) Copyright (c) 1984, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
-static char sccsid[] = "@(#)arp.c 8.2 (Berkeley) 1/2/94";
+static char const sccsid[] = "@(#)from: arp.c 8.2 (Berkeley) 1/2/94";
+static char const freebsdid[] = "$Id$";
#endif /* not lint */
/*
@@ -52,7 +53,9 @@ static char sccsid[] = "@(#)arp.c 8.2 (Berkeley) 1/2/94";
#include <sys/param.h>
#include <sys/file.h>
#include <sys/socket.h>
+#include <sys/sockio.h>
#include <sys/sysctl.h>
+#include <sys/ioctl.h>
#include <net/if.h>
#include <net/if_dl.h>
@@ -68,14 +71,30 @@ static char sccsid[] = "@(#)arp.c 8.2 (Berkeley) 1/2/94";
#include <errno.h>
#include <nlist.h>
#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <strings.h>
#include <paths.h>
+void dump(u_long addr);
+int delete(char *host, char *info);
+void ether_print(u_char *cp);
+void usage(void);
+int set(int argc, char **argv);
+void get(char *host);
+int file(char *name);
+void getsocket(void);
+int ether_aton(char *a, u_char *n);
+int rtmsg(int cmd);
+void quit(char *msg);
+int get_ether_addr(u_long ipaddr, u_char *hwaddr);
+
extern int errno;
static int pid;
-static int kflag;
static int nflag;
static int s = -1;
+int
main(argc, argv)
int argc;
char **argv;
@@ -83,7 +102,7 @@ main(argc, argv)
int ch;
pid = getpid();
- while ((ch = getopt(argc, argv, "andfs")) != EOF)
+ while ((ch = getopt(argc, argv, "andfsS")) != EOF)
switch((char)ch) {
case 'a':
dump(0);
@@ -96,6 +115,9 @@ main(argc, argv)
case 'n':
nflag = 1;
continue;
+ case 'S':
+ delete(argv[2], NULL);
+ /* FALL THROUGH */
case 's':
if (argc < 4 || argc > 7)
usage();
@@ -103,8 +125,7 @@ main(argc, argv)
case 'f' :
if (argc != 3)
usage();
- file(argv[2]);
- exit(0);
+ return (file(argv[2]));
case '?':
default:
usage();
@@ -118,8 +139,8 @@ main(argc, argv)
/*
* Process a file to set standard arp entries
*/
-file(name)
- char *name;
+int
+file(char *name)
{
FILE *fp;
int i, retval;
@@ -150,7 +171,9 @@ file(name)
return (retval);
}
-getsocket() {
+void
+getsocket(void)
+{
if (s < 0) {
s = socket(PF_ROUTE, SOCK_RAW, 0);
if (s < 0) {
@@ -172,9 +195,8 @@ struct {
/*
* Set an individual arp entry
*/
-set(argc, argv)
- int argc;
- char **argv;
+int
+set(int argc, char **argv)
{
struct hostent *hp;
register struct sockaddr_inarp *sin = &sin_m;
@@ -198,9 +220,6 @@ set(argc, argv)
bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
sizeof sin->sin_addr);
}
- ea = (u_char *)LLADDR(&sdl_m);
- if (ether_aton(eaddr, ea) == 0)
- sdl_m.sdl_alen = 6;
doing_proxy = flags = export_only = expire_time = 0;
while (argc-- > 0) {
if (strncmp(argv[0], "temp", 4) == 0) {
@@ -217,6 +236,16 @@ set(argc, argv)
}
argv++;
}
+ ea = (u_char *)LLADDR(&sdl_m);
+ if (doing_proxy && !strcmp(eaddr, "auto")) {
+ if (!get_ether_addr(sin->sin_addr.s_addr, ea)) {
+ return (1);
+ }
+ sdl_m.sdl_alen = 6;
+ } else {
+ if (ether_aton(eaddr, ea) == 0)
+ sdl_m.sdl_alen = 6;
+ }
tryagain:
if (rtmsg(RTM_GET) < 0) {
perror(host);
@@ -257,12 +286,11 @@ overwrite:
/*
* Display an individual arp entry
*/
-get(host)
- char *host;
+void
+get(char *host)
{
struct hostent *hp;
struct sockaddr_inarp *sin = &sin_m;
- u_char *ea;
sin_m = blank_sin;
sin->sin_addr.s_addr = inet_addr(host);
@@ -286,16 +314,13 @@ get(host)
/*
* Delete an arp entry
*/
-delete(host, info)
- char *host;
- char *info;
+int
+delete(char *host, char *info)
{
struct hostent *hp;
register struct sockaddr_inarp *sin = &sin_m;
register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
struct sockaddr_dl *sdl;
- u_char *ea;
- char *eaddr;
if (info && strncmp(info, "pro", 3) )
export_only = 1;
@@ -339,15 +364,18 @@ delete:
printf("cannot locate %s\n", host);
return (1);
}
- if (rtmsg(RTM_DELETE) == 0)
+ if (rtmsg(RTM_DELETE) == 0) {
printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr));
+ return (0);
+ }
+ return (1);
}
/*
* Dump the entire arp table
*/
-dump(addr)
-u_long addr;
+void
+dump(u_long addr)
{
int mib[6];
size_t needed;
@@ -413,15 +441,14 @@ u_long addr;
}
}
-ether_print(cp)
- u_char *cp;
+void
+ether_print(u_char *cp)
{
printf("%x:%x:%x:%x:%x:%x", cp[0], cp[1], cp[2], cp[3], cp[4], cp[5]);
}
-ether_aton(a, n)
- char *a;
- u_char *n;
+int
+ether_aton(char *a, u_char *n)
{
int i, o[6];
@@ -436,17 +463,20 @@ ether_aton(a, n)
return (0);
}
-usage()
+void
+usage(void)
{
printf("usage: arp hostname\n");
printf(" arp -a [kernel] [kernel_memory]\n");
printf(" arp -d hostname\n");
printf(" arp -s hostname ether_addr [temp] [pub]\n");
+ printf(" arp -S hostname ether_addr [temp] [pub]\n");
printf(" arp -f filename\n");
exit(1);
}
-rtmsg(cmd)
+int
+rtmsg(int cmd)
{
static int seq;
int rlen;
@@ -511,9 +541,110 @@ doit:
return (0);
}
-quit(msg)
-char *msg;
+void
+quit(char *msg)
{
fprintf(stderr, "%s\n", msg);
exit(1);
}
+
+/*
+ * get_ether_addr - get the hardware address of an interface on the
+ * the same subnet as ipaddr.
+ */
+#define MAX_IFS 32
+
+int
+get_ether_addr(u_long ipaddr, u_char *hwaddr)
+{
+ struct ifreq *ifr, *ifend, *ifp;
+ u_long ina, mask;
+ struct sockaddr_dl *dla;
+ struct ifreq ifreq;
+ struct ifconf ifc;
+ struct ifreq ifs[MAX_IFS];
+ int s;
+
+ s = socket(AF_INET, SOCK_DGRAM, 0);
+ if (s < 0) {
+ perror("socket");
+ exit(1);
+ }
+
+ ifc.ifc_len = sizeof(ifs);
+ ifc.ifc_req = ifs;
+ if (ioctl(s, SIOCGIFCONF, &ifc) < 0) {
+ fprintf(stderr, "ioctl(SIOCGIFCONF): \n");
+ close(s);
+ return 0;
+ }
+
+ /*
+ * Scan through looking for an interface with an Internet
+ * address on the same subnet as `ipaddr'.
+ */
+ ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
+ for (ifr = ifc.ifc_req; ifr < ifend; ) {
+ if (ifr->ifr_addr.sa_family == AF_INET) {
+ ina = ((struct sockaddr_in *)
+ &ifr->ifr_addr)->sin_addr.s_addr;
+ strncpy(ifreq.ifr_name, ifr->ifr_name,
+ sizeof(ifreq.ifr_name));
+ /*
+ * Check that the interface is up,
+ * and not point-to-point or loopback.
+ */
+ if (ioctl(s, SIOCGIFFLAGS, &ifreq) < 0)
+ continue;
+ if ((ifreq.ifr_flags &
+ (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|
+ IFF_LOOPBACK|IFF_NOARP))
+ != (IFF_UP|IFF_BROADCAST))
+ goto nextif;
+ /*
+ * Get its netmask and check that it's on
+ * the right subnet.
+ */
+ if (ioctl(s, SIOCGIFNETMASK, &ifreq) < 0)
+ continue;
+ mask = ((struct sockaddr_in *)
+ &ifreq.ifr_addr)->sin_addr.s_addr;
+ if ((ipaddr & mask) != (ina & mask))
+ goto nextif;
+ break;
+ }
+nextif:
+ ifr = (struct ifreq *)
+ ((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
+ }
+
+ if (ifr >= ifend) {
+ close(s);
+ return 0;
+ }
+
+ /*
+ * Now scan through again looking for a link-level address
+ * for this interface.
+ */
+ ifp = ifr;
+ for (ifr = ifc.ifc_req; ifr < ifend; ) {
+ if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0
+ && ifr->ifr_addr.sa_family == AF_LINK) {
+ /*
+ * Found the link-level address - copy it out
+ */
+ dla = (struct sockaddr_dl *) &ifr->ifr_addr;
+ memcpy(hwaddr, LLADDR(dla), dla->sdl_alen);
+ close (s);
+ printf("using interface %s for proxy with address ",
+ ifp->ifr_name);
+ ether_print(hwaddr);
+ printf("\n");
+ return dla->sdl_alen;
+ }
+ ifr = (struct ifreq *)
+ ((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
+ }
+ return 0;
+}
OpenPOWER on IntegriCloud