ed7509ace4
Remove lots'o'hacks. looutput is now static. Other callers who want to use loopback to allow shortcutting should call the special entrypoint for this, if_simloop(), which is specifically designed for this purpose. Using looutput for this purpose was problematic, particularly with bpf and trying to keep track of whether one should be using the charateristics of the loopback interface or the interface (e.g. if_ethersubr.c) that was requesting the loopback. There was a whole class of errors due to this mis-use each of which had hacks to cover them up. Consists largly of hack removal :-)
650 lines
19 KiB
C
650 lines
19 KiB
C
/*
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* Copyright (c) 1982, 1986, 1988, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)if_ether.c 8.1 (Berkeley) 6/10/93
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* $Id: if_ether.c,v 1.46 1998/06/07 17:12:12 dfr Exp $
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*/
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/*
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* Ethernet address resolution protocol.
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* TODO:
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* add "inuse/lock" bit (or ref. count) along with valid bit
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*/
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#include "opt_inet.h"
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#include <sys/param.h>
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#include <sys/kernel.h>
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#include <sys/sysctl.h>
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#include <sys/systm.h>
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#include <sys/mbuf.h>
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#include <sys/malloc.h>
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#include <sys/socket.h>
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#include <sys/syslog.h>
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#include <net/if.h>
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#include <net/if_dl.h>
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#include <net/route.h>
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#include <net/netisr.h>
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#include <netinet/in.h>
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#include <netinet/in_var.h>
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#include <netinet/if_ether.h>
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#define SIN(s) ((struct sockaddr_in *)s)
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#define SDL(s) ((struct sockaddr_dl *)s)
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SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
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/* timer values */
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static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
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static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
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static int arpt_down = 20; /* once declared down, don't send for 20 sec */
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SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW,
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&arpt_prune, 0, "");
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SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
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&arpt_keep, 0, "");
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SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
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&arpt_down, 0, "");
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#define rt_expire rt_rmx.rmx_expire
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struct llinfo_arp {
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LIST_ENTRY(llinfo_arp) la_le;
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struct rtentry *la_rt;
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struct mbuf *la_hold; /* last packet until resolved/timeout */
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long la_asked; /* last time we QUERIED for this addr */
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#define la_timer la_rt->rt_rmx.rmx_expire /* deletion time in seconds */
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};
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static LIST_HEAD(, llinfo_arp) llinfo_arp;
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struct ifqueue arpintrq = {0, 0, 0, 50};
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static int arp_inuse, arp_allocated;
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static int arp_maxtries = 5;
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static int useloopback = 1; /* use loopback interface for local traffic */
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static int arp_proxyall = 0;
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SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
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&arp_maxtries, 0, "");
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SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
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&useloopback, 0, "");
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SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
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&arp_proxyall, 0, "");
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static void arp_rtrequest __P((int, struct rtentry *, struct sockaddr *));
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static void arprequest __P((struct arpcom *,
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struct in_addr *, struct in_addr *, u_char *));
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static void arpintr __P((void));
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static void arptfree __P((struct llinfo_arp *));
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static void arptimer __P((void *));
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static struct llinfo_arp
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*arplookup __P((u_long, int, int));
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#ifdef INET
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static void in_arpinput __P((struct mbuf *));
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#endif
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/*
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* Timeout routine. Age arp_tab entries periodically.
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*/
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/* ARGSUSED */
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static void
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arptimer(ignored_arg)
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void *ignored_arg;
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{
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int s = splnet();
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register struct llinfo_arp *la = llinfo_arp.lh_first;
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struct llinfo_arp *ola;
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timeout(arptimer, (caddr_t)0, arpt_prune * hz);
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while ((ola = la) != 0) {
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register struct rtentry *rt = la->la_rt;
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la = la->la_le.le_next;
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if (rt->rt_expire && rt->rt_expire <= time_second)
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arptfree(ola); /* timer has expired, clear */
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}
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splx(s);
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}
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/*
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* Parallel to llc_rtrequest.
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*/
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static void
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arp_rtrequest(req, rt, sa)
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int req;
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register struct rtentry *rt;
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struct sockaddr *sa;
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{
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register struct sockaddr *gate = rt->rt_gateway;
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register struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
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static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
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static int arpinit_done;
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if (!arpinit_done) {
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arpinit_done = 1;
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LIST_INIT(&llinfo_arp);
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timeout(arptimer, (caddr_t)0, hz);
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}
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if (rt->rt_flags & RTF_GATEWAY)
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return;
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switch (req) {
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case RTM_ADD:
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/*
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* XXX: If this is a manually added route to interface
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* such as older version of routed or gated might provide,
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* restore cloning bit.
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*/
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if ((rt->rt_flags & RTF_HOST) == 0 &&
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SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
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rt->rt_flags |= RTF_CLONING;
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if (rt->rt_flags & RTF_CLONING) {
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/*
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* Case 1: This route should come from a route to iface.
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*/
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rt_setgate(rt, rt_key(rt),
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(struct sockaddr *)&null_sdl);
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gate = rt->rt_gateway;
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SDL(gate)->sdl_type = rt->rt_ifp->if_type;
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SDL(gate)->sdl_index = rt->rt_ifp->if_index;
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rt->rt_expire = time_second;
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break;
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}
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/* Announce a new entry if requested. */
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if (rt->rt_flags & RTF_ANNOUNCE)
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arprequest((struct arpcom *)rt->rt_ifp,
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&SIN(rt_key(rt))->sin_addr,
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&SIN(rt_key(rt))->sin_addr,
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(u_char *)LLADDR(SDL(gate)));
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/*FALLTHROUGH*/
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case RTM_RESOLVE:
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if (gate->sa_family != AF_LINK ||
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gate->sa_len < sizeof(null_sdl)) {
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log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
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break;
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}
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SDL(gate)->sdl_type = rt->rt_ifp->if_type;
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SDL(gate)->sdl_index = rt->rt_ifp->if_index;
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if (la != 0)
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break; /* This happens on a route change */
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/*
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* Case 2: This route may come from cloning, or a manual route
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* add with a LL address.
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*/
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R_Malloc(la, struct llinfo_arp *, sizeof(*la));
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rt->rt_llinfo = (caddr_t)la;
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if (la == 0) {
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log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
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break;
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}
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arp_inuse++, arp_allocated++;
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Bzero(la, sizeof(*la));
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la->la_rt = rt;
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rt->rt_flags |= RTF_LLINFO;
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LIST_INSERT_HEAD(&llinfo_arp, la, la_le);
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#ifdef INET
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/*
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* This keeps the multicast addresses from showing up
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* in `arp -a' listings as unresolved. It's not actually
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* functional. Then the same for broadcast.
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*/
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if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
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ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt))->sin_addr,
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LLADDR(SDL(gate)));
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SDL(gate)->sdl_alen = 6;
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rt->rt_expire = 0;
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}
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if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
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memcpy(LLADDR(SDL(gate)), etherbroadcastaddr, 6);
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SDL(gate)->sdl_alen = 6;
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rt->rt_expire = 0;
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}
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#endif
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if (SIN(rt_key(rt))->sin_addr.s_addr ==
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(IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
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/*
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* This test used to be
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* if (loif.if_flags & IFF_UP)
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* It allowed local traffic to be forced
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* through the hardware by configuring the loopback down.
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* However, it causes problems during network configuration
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* for boards that can't receive packets they send.
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* It is now necessary to clear "useloopback" and remove
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* the route to force traffic out to the hardware.
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*/
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rt->rt_expire = 0;
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Bcopy(((struct arpcom *)rt->rt_ifp)->ac_enaddr,
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LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);
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if (useloopback)
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rt->rt_ifp = loif;
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}
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break;
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case RTM_DELETE:
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if (la == 0)
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break;
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arp_inuse--;
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LIST_REMOVE(la, la_le);
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rt->rt_llinfo = 0;
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rt->rt_flags &= ~RTF_LLINFO;
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if (la->la_hold)
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m_freem(la->la_hold);
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Free((caddr_t)la);
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}
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}
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/*
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* Broadcast an ARP request. Caller specifies:
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* - arp header source ip address
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* - arp header target ip address
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* - arp header source ethernet address
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*/
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static void
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arprequest(ac, sip, tip, enaddr)
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register struct arpcom *ac;
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register struct in_addr *sip, *tip;
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register u_char *enaddr;
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{
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register struct mbuf *m;
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register struct ether_header *eh;
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register struct ether_arp *ea;
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struct sockaddr sa;
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if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
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return;
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m->m_len = sizeof(*ea);
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m->m_pkthdr.len = sizeof(*ea);
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MH_ALIGN(m, sizeof(*ea));
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ea = mtod(m, struct ether_arp *);
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eh = (struct ether_header *)sa.sa_data;
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bzero((caddr_t)ea, sizeof (*ea));
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(void)memcpy(eh->ether_dhost, etherbroadcastaddr, sizeof(eh->ether_dhost));
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eh->ether_type = htons(ETHERTYPE_ARP); /* if_output will not swap */
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ea->arp_hrd = htons(ARPHRD_ETHER);
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ea->arp_pro = htons(ETHERTYPE_IP);
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ea->arp_hln = sizeof(ea->arp_sha); /* hardware address length */
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ea->arp_pln = sizeof(ea->arp_spa); /* protocol address length */
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ea->arp_op = htons(ARPOP_REQUEST);
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(void)memcpy(ea->arp_sha, enaddr, sizeof(ea->arp_sha));
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(void)memcpy(ea->arp_spa, sip, sizeof(ea->arp_spa));
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(void)memcpy(ea->arp_tpa, tip, sizeof(ea->arp_tpa));
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sa.sa_family = AF_UNSPEC;
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sa.sa_len = sizeof(sa);
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(*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0);
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}
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/*
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* Resolve an IP address into an ethernet address. If success,
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* desten is filled in. If there is no entry in arptab,
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* set one up and broadcast a request for the IP address.
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* Hold onto this mbuf and resend it once the address
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* is finally resolved. A return value of 1 indicates
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* that desten has been filled in and the packet should be sent
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* normally; a 0 return indicates that the packet has been
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* taken over here, either now or for later transmission.
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*/
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int
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arpresolve(ac, rt, m, dst, desten, rt0)
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register struct arpcom *ac;
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register struct rtentry *rt;
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struct mbuf *m;
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register struct sockaddr *dst;
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register u_char *desten;
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struct rtentry *rt0;
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{
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register struct llinfo_arp *la;
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struct sockaddr_dl *sdl;
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if (m->m_flags & M_BCAST) { /* broadcast */
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(void)memcpy(desten, etherbroadcastaddr, sizeof(etherbroadcastaddr));
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return (1);
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}
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if (m->m_flags & M_MCAST) { /* multicast */
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ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
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return(1);
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}
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if (rt)
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la = (struct llinfo_arp *)rt->rt_llinfo;
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else {
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la = arplookup(SIN(dst)->sin_addr.s_addr, 1, 0);
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if (la)
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rt = la->la_rt;
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}
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if (la == 0 || rt == 0) {
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log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s%s%s\n",
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inet_ntoa(SIN(dst)->sin_addr), la ? "la" : "",
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rt ? "rt" : "");
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m_freem(m);
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return (0);
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}
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sdl = SDL(rt->rt_gateway);
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/*
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* Check the address family and length is valid, the address
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* is resolved; otherwise, try to resolve.
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*/
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if ((rt->rt_expire == 0 || rt->rt_expire > time_second) &&
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sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
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bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
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return 1;
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}
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/*
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* There is an arptab entry, but no ethernet address
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* response yet. Replace the held mbuf with this
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* latest one.
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*/
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if (la->la_hold)
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m_freem(la->la_hold);
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la->la_hold = m;
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if (rt->rt_expire) {
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rt->rt_flags &= ~RTF_REJECT;
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if (la->la_asked == 0 || rt->rt_expire != time_second) {
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rt->rt_expire = time_second;
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if (la->la_asked++ < arp_maxtries)
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arprequest(ac,
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&SIN(rt->rt_ifa->ifa_addr)->sin_addr,
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&SIN(dst)->sin_addr, ac->ac_enaddr);
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else {
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rt->rt_flags |= RTF_REJECT;
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rt->rt_expire += arpt_down;
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la->la_asked = 0;
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}
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}
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}
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return (0);
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}
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/*
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* Common length and type checks are done here,
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* then the protocol-specific routine is called.
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*/
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static void
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arpintr()
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{
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register struct mbuf *m;
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register struct arphdr *ar;
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int s;
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while (arpintrq.ifq_head) {
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s = splimp();
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IF_DEQUEUE(&arpintrq, m);
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splx(s);
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if (m == 0 || (m->m_flags & M_PKTHDR) == 0)
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panic("arpintr");
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if (m->m_len >= sizeof(struct arphdr) &&
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(ar = mtod(m, struct arphdr *)) &&
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ntohs(ar->ar_hrd) == ARPHRD_ETHER &&
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m->m_len >=
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sizeof(struct arphdr) + 2 * ar->ar_hln + 2 * ar->ar_pln)
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switch (ntohs(ar->ar_pro)) {
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#ifdef INET
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case ETHERTYPE_IP:
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in_arpinput(m);
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continue;
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#endif
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}
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m_freem(m);
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}
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}
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NETISR_SET(NETISR_ARP, arpintr);
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#ifdef INET
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/*
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* ARP for Internet protocols on 10 Mb/s Ethernet.
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* Algorithm is that given in RFC 826.
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* In addition, a sanity check is performed on the sender
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* protocol address, to catch impersonators.
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* We no longer handle negotiations for use of trailer protocol:
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* Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
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* along with IP replies if we wanted trailers sent to us,
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* and also sent them in response to IP replies.
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* This allowed either end to announce the desire to receive
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* trailer packets.
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* We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
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* but formerly didn't normally send requests.
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*/
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static void
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in_arpinput(m)
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struct mbuf *m;
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{
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register struct ether_arp *ea;
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register struct arpcom *ac = (struct arpcom *)m->m_pkthdr.rcvif;
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struct ether_header *eh;
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register struct llinfo_arp *la = 0;
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register struct rtentry *rt;
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struct in_ifaddr *ia, *maybe_ia = 0;
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struct sockaddr_dl *sdl;
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struct sockaddr sa;
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struct in_addr isaddr, itaddr, myaddr;
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int op;
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ea = mtod(m, struct ether_arp *);
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op = ntohs(ea->arp_op);
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(void)memcpy(&isaddr, ea->arp_spa, sizeof (isaddr));
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(void)memcpy(&itaddr, ea->arp_tpa, sizeof (itaddr));
|
|
for (ia = in_ifaddrhead.tqh_first; ia; ia = ia->ia_link.tqe_next)
|
|
if (ia->ia_ifp == &ac->ac_if) {
|
|
maybe_ia = ia;
|
|
if ((itaddr.s_addr == ia->ia_addr.sin_addr.s_addr) ||
|
|
(isaddr.s_addr == ia->ia_addr.sin_addr.s_addr))
|
|
break;
|
|
}
|
|
if (maybe_ia == 0) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
myaddr = ia ? ia->ia_addr.sin_addr : maybe_ia->ia_addr.sin_addr;
|
|
if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)ac->ac_enaddr,
|
|
sizeof (ea->arp_sha))) {
|
|
m_freem(m); /* it's from me, ignore it. */
|
|
return;
|
|
}
|
|
if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)etherbroadcastaddr,
|
|
sizeof (ea->arp_sha))) {
|
|
log(LOG_ERR,
|
|
"arp: ether address is broadcast for IP address %s!\n",
|
|
inet_ntoa(isaddr));
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
if (isaddr.s_addr == myaddr.s_addr) {
|
|
log(LOG_ERR,
|
|
"arp: %6D is using my IP address %s!\n",
|
|
ea->arp_sha, ":", inet_ntoa(isaddr));
|
|
itaddr = myaddr;
|
|
goto reply;
|
|
}
|
|
la = arplookup(isaddr.s_addr, itaddr.s_addr == myaddr.s_addr, 0);
|
|
if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
|
|
if (sdl->sdl_alen &&
|
|
bcmp((caddr_t)ea->arp_sha, LLADDR(sdl), sdl->sdl_alen))
|
|
log(LOG_INFO, "arp: %s moved from %6D to %6D\n",
|
|
inet_ntoa(isaddr), (u_char *)LLADDR(sdl), ":",
|
|
ea->arp_sha, ":");
|
|
(void)memcpy(LLADDR(sdl), ea->arp_sha, sizeof(ea->arp_sha));
|
|
sdl->sdl_alen = sizeof(ea->arp_sha);
|
|
if (rt->rt_expire)
|
|
rt->rt_expire = time_second + arpt_keep;
|
|
rt->rt_flags &= ~RTF_REJECT;
|
|
la->la_asked = 0;
|
|
if (la->la_hold) {
|
|
(*ac->ac_if.if_output)(&ac->ac_if, la->la_hold,
|
|
rt_key(rt), rt);
|
|
la->la_hold = 0;
|
|
}
|
|
}
|
|
reply:
|
|
if (op != ARPOP_REQUEST) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
if (itaddr.s_addr == myaddr.s_addr) {
|
|
/* I am the target */
|
|
(void)memcpy(ea->arp_tha, ea->arp_sha, sizeof(ea->arp_sha));
|
|
(void)memcpy(ea->arp_sha, ac->ac_enaddr, sizeof(ea->arp_sha));
|
|
} else {
|
|
la = arplookup(itaddr.s_addr, 0, SIN_PROXY);
|
|
if (la == NULL) {
|
|
struct sockaddr_in sin;
|
|
|
|
if (!arp_proxyall) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
|
|
bzero(&sin, sizeof sin);
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_len = sizeof sin;
|
|
sin.sin_addr = itaddr;
|
|
|
|
rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
|
|
if (!rt) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
/*
|
|
* Don't send proxies for nodes on the same interface
|
|
* as this one came out of, or we'll get into a fight
|
|
* over who claims what Ether address.
|
|
*/
|
|
if (rt->rt_ifp == &ac->ac_if) {
|
|
rtfree(rt);
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
(void)memcpy(ea->arp_tha, ea->arp_sha, sizeof(ea->arp_sha));
|
|
(void)memcpy(ea->arp_sha, ac->ac_enaddr, sizeof(ea->arp_sha));
|
|
rtfree(rt);
|
|
#ifdef DEBUG_PROXY
|
|
printf("arp: proxying for %s\n",
|
|
inet_ntoa(itaddr));
|
|
#endif
|
|
} else {
|
|
rt = la->la_rt;
|
|
(void)memcpy(ea->arp_tha, ea->arp_sha, sizeof(ea->arp_sha));
|
|
sdl = SDL(rt->rt_gateway);
|
|
(void)memcpy(ea->arp_sha, LLADDR(sdl), sizeof(ea->arp_sha));
|
|
}
|
|
}
|
|
|
|
(void)memcpy(ea->arp_tpa, ea->arp_spa, sizeof(ea->arp_spa));
|
|
(void)memcpy(ea->arp_spa, &itaddr, sizeof(ea->arp_spa));
|
|
ea->arp_op = htons(ARPOP_REPLY);
|
|
ea->arp_pro = htons(ETHERTYPE_IP); /* let's be sure! */
|
|
eh = (struct ether_header *)sa.sa_data;
|
|
(void)memcpy(eh->ether_dhost, ea->arp_tha, sizeof(eh->ether_dhost));
|
|
eh->ether_type = htons(ETHERTYPE_ARP);
|
|
sa.sa_family = AF_UNSPEC;
|
|
sa.sa_len = sizeof(sa);
|
|
(*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Free an arp entry.
|
|
*/
|
|
static void
|
|
arptfree(la)
|
|
register struct llinfo_arp *la;
|
|
{
|
|
register struct rtentry *rt = la->la_rt;
|
|
register struct sockaddr_dl *sdl;
|
|
if (rt == 0)
|
|
panic("arptfree");
|
|
if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
|
|
sdl->sdl_family == AF_LINK) {
|
|
sdl->sdl_alen = 0;
|
|
la->la_asked = 0;
|
|
rt->rt_flags &= ~RTF_REJECT;
|
|
return;
|
|
}
|
|
rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
|
|
0, (struct rtentry **)0);
|
|
}
|
|
/*
|
|
* Lookup or enter a new address in arptab.
|
|
*/
|
|
static struct llinfo_arp *
|
|
arplookup(addr, create, proxy)
|
|
u_long addr;
|
|
int create, proxy;
|
|
{
|
|
register struct rtentry *rt;
|
|
static struct sockaddr_inarp sin = {sizeof(sin), AF_INET };
|
|
const char *why = 0;
|
|
|
|
sin.sin_addr.s_addr = addr;
|
|
sin.sin_other = proxy ? SIN_PROXY : 0;
|
|
rt = rtalloc1((struct sockaddr *)&sin, create, 0UL);
|
|
if (rt == 0)
|
|
return (0);
|
|
rt->rt_refcnt--;
|
|
|
|
if (rt->rt_flags & RTF_GATEWAY)
|
|
why = "host is not on local network";
|
|
else if ((rt->rt_flags & RTF_LLINFO) == 0)
|
|
why = "could not allocate llinfo";
|
|
else if (rt->rt_gateway->sa_family != AF_LINK)
|
|
why = "gateway route is not ours";
|
|
|
|
if (why && create) {
|
|
log(LOG_DEBUG, "arplookup %s failed: %s\n",
|
|
inet_ntoa(sin.sin_addr), why);
|
|
return 0;
|
|
} else if (why) {
|
|
return 0;
|
|
}
|
|
return ((struct llinfo_arp *)rt->rt_llinfo);
|
|
}
|
|
|
|
void
|
|
arp_ifinit(ac, ifa)
|
|
struct arpcom *ac;
|
|
struct ifaddr *ifa;
|
|
{
|
|
if (ntohl(IA_SIN(ifa)->sin_addr.s_addr) != INADDR_ANY)
|
|
arprequest(ac, &IA_SIN(ifa)->sin_addr,
|
|
&IA_SIN(ifa)->sin_addr, ac->ac_enaddr);
|
|
ifa->ifa_rtrequest = arp_rtrequest;
|
|
ifa->ifa_flags |= RTF_CLONING;
|
|
}
|