2 * sys-bsd.c - System-dependent procedures for setting up
3 * PPP interfaces on bsd-4.4-ish systems (including 386BSD, NetBSD, etc.)
5 * Copyright (c) 1989 Carnegie Mellon University.
8 * Redistribution and use in source and binary forms are permitted
9 * provided that the above copyright notice and this paragraph are
10 * duplicated in all such forms and that any documentation,
11 * advertising materials, and other materials related to such
12 * distribution and use acknowledge that the software was developed
13 * by Carnegie Mellon University. The name of the
14 * University may not be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 * $FreeBSD: src/usr.sbin/ppp/arp.c,v 1.37.2.3 2002/09/01 02:12:22 brian Exp $
28 #include <sys/param.h>
29 #include <sys/socket.h>
31 #include <net/route.h>
32 #include <net/if_dl.h>
33 #include <netinet/in.h>
34 #include <netinet/if_ether.h>
35 #include <arpa/inet.h>
36 #include <netinet/in_systm.h>
37 #include <netinet/ip.h>
44 #include <sys/sysctl.h>
56 #include "throughput.h"
57 #include "slcompress.h"
63 #include "descriptor.h"
78 * SET_SA_FAMILY - set the sa_family field of a struct sockaddr,
81 #define SET_SA_FAMILY(addr, family) \
82 memset((char *) &(addr), '\0', sizeof(addr)); \
83 addr.sa_family = (family); \
84 addr.sa_len = sizeof(addr);
90 * arp_SetProxy - Make a proxy ARP entry for the peer.
94 struct sockaddr_inarp dst;
95 struct sockaddr_dl hwa;
100 arp_ProxySub(struct bundle *bundle, struct in_addr addr, int add)
105 * Get the hardware address of an interface on the same subnet as our local
109 memset(&arpmsg, 0, sizeof arpmsg);
110 if (!arp_EtherAddr(addr, &arpmsg.hwa, 0)) {
111 log_Printf(LogWARN, "%s: Cannot determine ethernet address for proxy ARP\n",
115 routes = ID0socket(PF_ROUTE, SOCK_RAW, AF_INET);
117 log_Printf(LogERROR, "arp_SetProxy: opening routing socket: %s\n",
121 arpmsg.hdr.rtm_type = add ? RTM_ADD : RTM_DELETE;
122 arpmsg.hdr.rtm_flags = RTF_ANNOUNCE | RTF_HOST | RTF_STATIC;
123 arpmsg.hdr.rtm_version = RTM_VERSION;
124 arpmsg.hdr.rtm_seq = ++bundle->routing_seq;
125 arpmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY;
126 arpmsg.hdr.rtm_inits = RTV_EXPIRE;
127 arpmsg.dst.sin_len = sizeof(struct sockaddr_inarp);
128 arpmsg.dst.sin_family = AF_INET;
129 arpmsg.dst.sin_addr.s_addr = addr.s_addr;
130 arpmsg.dst.sin_other = SIN_PROXY;
132 arpmsg.hdr.rtm_msglen = (char *) &arpmsg.hwa - (char *) &arpmsg
133 + arpmsg.hwa.sdl_len;
136 if (ID0write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0 &&
137 !(!add && errno == ESRCH)) {
138 log_Printf(LogERROR, "%s proxy arp entry %s: %s\n",
139 add ? "Add" : "Delete", inet_ntoa(addr), strerror(errno));
148 arp_SetProxy(struct bundle *bundle, struct in_addr addr)
150 return (arp_ProxySub(bundle, addr, 1));
154 * arp_ClearProxy - Delete the proxy ARP entry for the peer.
157 arp_ClearProxy(struct bundle *bundle, struct in_addr addr)
159 return (arp_ProxySub(bundle, addr, 0));
162 #else /* RTM_VERSION */
165 * arp_SetProxy - Make a proxy ARP entry for the peer.
168 arp_SetProxy(struct bundle *bundle, struct in_addr addr, int s)
170 struct arpreq arpreq;
172 struct sockaddr_dl sdl;
176 memset(&arpreq, '\0', sizeof arpreq);
179 * Get the hardware address of an interface on the same subnet as our local
182 if (!arp_EtherAddr(addr, &dls.sdl, 1)) {
183 log_Printf(LOG_PHASE_BIT, "Cannot determine ethernet address for "
187 arpreq.arp_ha.sa_len = sizeof(struct sockaddr);
188 arpreq.arp_ha.sa_family = AF_UNSPEC;
189 memcpy(arpreq.arp_ha.sa_data, LLADDR(&dls.sdl), dls.sdl.sdl_alen);
190 SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
191 ((struct sockaddr_in *)&arpreq.arp_pa)->sin_addr.s_addr = addr.s_addr;
192 arpreq.arp_flags = ATF_PERM | ATF_PUBL;
193 if (ID0ioctl(s, SIOCSARP, (caddr_t) & arpreq) < 0) {
194 log_Printf(LogERROR, "arp_SetProxy: ioctl(SIOCSARP): %s\n",
202 * arp_ClearProxy - Delete the proxy ARP entry for the peer.
205 arp_ClearProxy(struct bundle *bundle, struct in_addr addr, int s)
207 struct arpreq arpreq;
209 memset(&arpreq, '\0', sizeof arpreq);
210 SET_SA_FAMILY(arpreq.arp_pa, AF_INET);
211 ((struct sockaddr_in *)&arpreq.arp_pa)->sin_addr.s_addr = addr.s_addr;
212 if (ID0ioctl(s, SIOCDARP, (caddr_t) & arpreq) < 0) {
213 log_Printf(LogERROR, "arp_ClearProxy: ioctl(SIOCDARP): %s\n",
220 #endif /* RTM_VERSION */
224 * arp_EtherAddr - get the hardware address of an interface on the
225 * the same subnet as ipaddr.
229 arp_EtherAddr(struct in_addr ipaddr, struct sockaddr_dl *hwaddr,
234 char *buf, *ptr, *end;
235 struct if_msghdr *ifm;
236 struct ifa_msghdr *ifam;
237 struct sockaddr_dl *dl;
238 struct sockaddr *sa[RTAX_MAX];
244 mib[4] = NET_RT_IFLIST;
247 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) {
248 log_Printf(LogERROR, "arp_EtherAddr: sysctl: estimate: %s\n",
253 if ((buf = malloc(needed)) == NULL)
256 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
264 ifm = (struct if_msghdr *)ptr; /* On if_msghdr */
265 if (ifm->ifm_type != RTM_IFINFO)
267 dl = (struct sockaddr_dl *)(ifm + 1); /* Single _dl at end */
268 skip = (ifm->ifm_flags & (IFF_UP | IFF_BROADCAST | IFF_POINTOPOINT |
269 IFF_NOARP | IFF_LOOPBACK)) != (IFF_UP | IFF_BROADCAST);
270 ptr += ifm->ifm_msglen; /* First ifa_msghdr */
272 ifam = (struct ifa_msghdr *)ptr; /* Next ifa_msghdr (alias) */
273 if (ifam->ifam_type != RTM_NEWADDR) /* finished ? */
275 ptr += ifam->ifam_msglen;
276 if (skip || (ifam->ifam_addrs & (RTA_NETMASK|RTA_IFA)) !=
277 (RTA_NETMASK|RTA_IFA))
279 /* Found a candidate. Do the addresses match ? */
280 if (log_IsKept(LogDEBUG) &&
281 ptr == (char *)ifm + ifm->ifm_msglen + ifam->ifam_msglen)
282 log_Printf(LogDEBUG, "%.*s interface is a candidate for proxy\n",
283 dl->sdl_nlen, dl->sdl_data);
285 iface_ParseHdr(ifam, sa);
287 if (sa[RTAX_IFA]->sa_family == AF_INET) {
288 struct sockaddr_in *ifa, *netmask;
290 ifa = (struct sockaddr_in *)sa[RTAX_IFA];
291 netmask = (struct sockaddr_in *)sa[RTAX_NETMASK];
293 if (log_IsKept(LogDEBUG)) {
296 strncpy(a, inet_ntoa(netmask->sin_addr), sizeof a - 1);
297 a[sizeof a - 1] = '\0';
298 log_Printf(LogDEBUG, "Check addr %s, mask %s\n",
299 inet_ntoa(ifa->sin_addr), a);
302 if ((ifa->sin_addr.s_addr & netmask->sin_addr.s_addr) ==
303 (ipaddr.s_addr & netmask->sin_addr.s_addr)) {
304 log_Printf(verbose ? LogPHASE : LogDEBUG,
305 "Found interface %.*s for %s\n", dl->sdl_alen,
306 dl->sdl_data, inet_ntoa(ipaddr));
307 memcpy(hwaddr, dl, dl->sdl_len);