freebsd-dev/usr.sbin/ppp/arp.c
Poul-Henning Kamp 9c749ffb8b Here is a diff of /usr/src/usr.sbin/ppp against current. The diffs
add some logging functionality which I find very useful.
'set debug link' will record just link up/down and address assignments.
'set debug connect' will record the entire chat dialog
'set debug carrier' will record just chat lines including 'CARRIER'
(so that I can be sure I'm getting a 28.8 line).

There was a global change required to permit LogPrintf to take a bit
mask instead of a bit position value (to permit logging some events
on either of two flags, so that no change in 'set debug lcp' would
result from the code supporting 'link'.  Thus the diffs are rather
long for such a small change.  The man page is also touched.

Oh, and there was a slight syntax problem in route.c

Reviewed by:	phk
Submitted by:	Tony Kimball <alk@Think.COM>
1996-05-11 20:48:42 +00:00

427 lines
9.9 KiB
C

/*
* sys-bsd.c - System-dependent procedures for setting up
* PPP interfaces on bsd-4.4-ish systems (including 386BSD, NetBSD, etc.)
*
* Copyright (c) 1989 Carnegie Mellon University.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by Carnegie Mellon University. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* $Id: arp.c,v 1.4 1996/01/11 17:48:34 phk Exp $
*
*/
/*
* TODO:
*/
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/errno.h>
#include <unistd.h>
#include <string.h>
#include <net/if.h>
#include <net/route.h>
#include <net/if_dl.h>
#include <netinet/in.h>
#include <stdio.h>
#include <fcntl.h>
#ifdef __bsdi__
#include <kvm.h>
#endif
#include <net/if_types.h>
#include <netinet/in_var.h>
#include <netinet/if_ether.h>
#include "log.h"
#if RTM_VERSION >= 3
#include <netinet/if_ether.h>
#endif
static int rtm_seq;
static int get_ether_addr __P((int, u_long, struct sockaddr_dl *));
#define BCOPY(s, d, l) memcpy(d, s, l)
#define BZERO(s, n) memset(s, 0, n)
/*
* SET_SA_FAMILY - set the sa_family field of a struct sockaddr,
* if it exists.
*/
#define SET_SA_FAMILY(addr, family) \
BZERO((char *) &(addr), sizeof(addr)); \
addr.sa_family = (family); \
addr.sa_len = sizeof(addr);
#if RTM_VERSION >= 3
/*
* sifproxyarp - Make a proxy ARP entry for the peer.
*/
static struct {
struct rt_msghdr hdr;
struct sockaddr_inarp dst;
struct sockaddr_dl hwa;
char extra[128];
} arpmsg;
static int arpmsg_valid;
int
sifproxyarp(unit, hisaddr)
int unit;
u_long hisaddr;
{
int routes;
/*
* Get the hardware address of an interface on the same subnet
* as our local address.
*/
memset(&arpmsg, 0, sizeof(arpmsg));
if (!get_ether_addr(unit, hisaddr, &arpmsg.hwa)) {
logprintf("Cannot determine ethernet address for proxy ARP\n");
return 0;
}
if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
logprintf("sifproxyarp: opening routing socket: \n");
return 0;
}
arpmsg.hdr.rtm_type = RTM_ADD;
arpmsg.hdr.rtm_flags = RTF_ANNOUNCE | RTF_HOST | RTF_STATIC;
arpmsg.hdr.rtm_version = RTM_VERSION;
arpmsg.hdr.rtm_seq = ++rtm_seq;
arpmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY;
arpmsg.hdr.rtm_inits = RTV_EXPIRE;
arpmsg.dst.sin_len = sizeof(struct sockaddr_inarp);
arpmsg.dst.sin_family = AF_INET;
arpmsg.dst.sin_addr.s_addr = hisaddr;
arpmsg.dst.sin_other = SIN_PROXY;
arpmsg.hdr.rtm_msglen = (char *) &arpmsg.hwa - (char *) &arpmsg
+ arpmsg.hwa.sdl_len;
if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0) {
logprintf("add proxy arp entry: \n");
close(routes);
return 0;
}
close(routes);
arpmsg_valid = 1;
return 1;
}
/*
* cifproxyarp - Delete the proxy ARP entry for the peer.
*/
int
cifproxyarp(unit, hisaddr)
int unit;
u_long hisaddr;
{
int routes;
if (!arpmsg_valid)
return 0;
arpmsg_valid = 0;
arpmsg.hdr.rtm_type = RTM_DELETE;
arpmsg.hdr.rtm_seq = ++rtm_seq;
if ((routes = socket(PF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
logprintf("sifproxyarp: opening routing socket: \n");
return 0;
}
if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0) {
logprintf("delete proxy arp entry: \n");
close(routes);
return 0;
}
close(routes);
return 1;
}
#else /* RTM_VERSION */
/*
* sifproxyarp - Make a proxy ARP entry for the peer.
*/
int
sifproxyarp(unit, hisaddr)
int unit;
u_long hisaddr;
{
struct arpreq arpreq;
struct {
struct sockaddr_dl sdl;
char space[128];
} dls;
BZERO(&arpreq, sizeof(arpreq));
/*
* Get the hardware address of an interface on the same subnet
* as our local address.
*/
if (!get_ether_addr(unit, hisaddr, &dls.sdl)) {
LogPrintf(LOG_PHASE_BIT, "Cannot determine ethernet address for proxy ARP\n");
return 0;
}
arpreq.arp_ha.sa_len = sizeof(struct sockaddr);
arpreq.arp_ha.sa_family = AF_UNSPEC;
BCOPY(LLADDR(&dls.sdl), arpreq.arp_ha.sa_data, dls.sdl.sdl_alen);
SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = hisaddr;
arpreq.arp_flags = ATF_PERM | ATF_PUBL;
if (ioctl(unit, SIOCSARP, (caddr_t)&arpreq) < 0) {
fprintf(stderr, "ioctl(SIOCSARP): \n");
return 0;
}
return 1;
}
/*
* cifproxyarp - Delete the proxy ARP entry for the peer.
*/
int
cifproxyarp(unit, hisaddr)
int unit;
u_long hisaddr;
{
struct arpreq arpreq;
BZERO(&arpreq, sizeof(arpreq));
SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
((struct sockaddr_in *) &arpreq.arp_pa)->sin_addr.s_addr = hisaddr;
if (ioctl(unit, SIOCDARP, (caddr_t)&arpreq) < 0) {
fprintf(stderr, "ioctl(SIOCDARP): \n");
return 0;
}
return 1;
}
#endif /* RTM_VERSION */
/*
* 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(s, ipaddr, hwaddr)
int s;
u_long ipaddr;
struct sockaddr_dl *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];
ifc.ifc_len = sizeof(ifs);
ifc.ifc_req = ifs;
if (ioctl(s, SIOCGIFCONF, &ifc) < 0) {
fprintf(stderr, "ioctl(SIOCGIFCONF): \n");
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)
return 0;
LogPrintf(LOG_PHASE_BIT, "found interface %s for proxy arp\n", ifr->ifr_name);
/*
* 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;
#ifdef __bsdi__
if (dla->sdl_alen == 0)
kmemgetether(ifr->ifr_name, dla);
#endif
BCOPY(dla, hwaddr, dla->sdl_len);
return 1;
}
ifr = (struct ifreq *) ((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
}
return 0;
}
#ifdef __bsdi__
#include <nlist.h>
struct nlist nl[] = {
#define N_IFNET 0
{ "_ifnet" },
"",
};
kvm_t *kvmd;
/*
* Read kernel memory, return 0 on success.
*/
int
kread(addr, buf, size)
u_long addr;
char *buf;
int size;
{
if (kvm_read(kvmd, addr, buf, size) != size) {
/* XXX this duplicates kvm_read's error printout */
(void)fprintf(stderr, "kvm_read %s\n",
kvm_geterr(kvmd));
return (-1);
}
return (0);
}
kmemgetether(ifname, dlo)
char *ifname;
struct sockaddr_dl *dlo;
{
struct ifnet ifnet;
int n;
u_long addr, ifaddraddr, ifnetfound, ifaddrfound;
char name[32];
struct sockaddr *sa;
char *cp;
struct sockaddr_dl *sdl;
union {
struct ifaddr ifa;
struct in_ifaddr in;
} ifaddr;
struct arpcom ac;
kvmd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL);
if (kvmd) {
n = kvm_nlist(kvmd, nl);
if (n >= 0) {
addr = nl[N_IFNET].n_value;
kread(addr, (char *)&addr, sizeof(addr));
ifaddraddr = ifnetfound = 0;
while (addr || ifaddraddr) {
ifnetfound = addr;
if (ifaddraddr == 0) {
if (kread(addr, (char *)&ifnet, sizeof(ifnet)) ||
kread((u_long)ifnet.if_name, name, 16))
return;
name[15] = 0;
addr = (u_long) ifnet.if_next;
cp = (char *)index(name, '\0');
cp += sprintf(cp, "%d", ifnet.if_unit);
*cp = '\0';
ifaddraddr = (u_long)ifnet.if_addrlist;
}
ifaddrfound = ifaddraddr;
if (ifaddraddr) {
if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
ifaddraddr = 0;
continue;
}
#define CP(x) ((char *)(x))
cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) + CP(&ifaddr);
sa = (struct sockaddr *)cp;
if (sa->sa_family == AF_LINK && strcmp(ifname, name) == 0) {
sdl = (struct sockaddr_dl *)sa;
cp = (char *)LLADDR(sdl);
n = sdl->sdl_alen;
if (ifnet.if_type == IFT_ETHER) {
if (n == 0) {
kread(ifnetfound, (char *)&ac, sizeof(ac));
cp = (char *)LLADDR(sdl);
bcopy((char *)ac.ac_enaddr, cp, 6);
sdl->sdl_alen = 6;
}
bcopy(sdl, dlo, sizeof(*sdl));
return;
}
}
ifaddraddr = (u_long)ifaddr.ifa.ifa_next;
}
}
}
}
}
#endif
#ifdef DEBUG
main()
{
u_long ipaddr;
int s;
s = socket(AF_INET, SOCK_DGRAM, 0);
ipaddr = inet_addr("192.168.1.32");
sifproxyarp(s, ipaddr);
close(s);
}
#endif