bfe1aba468
dependency tracking and ordering enforcement. With this change, per-vnet initialization functions introduced with r190787 are no longer directly called from traditional initialization functions (which cc in most cases inlined to pre-r190787 code), but are instead registered via the vnet framework first, and are invoked only after all prerequisite modules have been initialized. In the long run, this framework should allow us to both initialize and dismantle multiple vnet instances in a correct order. The problem this change aims to solve is how to replay the initialization sequence of various network stack components, which have been traditionally triggered via different mechanisms (SYSINIT, protosw). Note that this initialization sequence was and still can be subtly different depending on whether certain pieces of code have been statically compiled into the kernel, loaded as modules by boot loader, or kldloaded at run time. The approach is simple - we record the initialization sequence established by the traditional mechanisms whenever vnet_mod_register() is called for a particular vnet module. The vnet_mod_register_multi() variant allows a single initializer function to be registered multiple times but with different arguments - currently this is only used in kern/uipc_domain.c by net_add_domain() with different struct domain * as arguments, which allows for protosw-registered initialization routines to be invoked in a correct order by the new vnet initialization framework. For the purpose of identifying vnet modules, each vnet module has to have a unique ID, which is statically assigned in sys/vimage.h. Dynamic assignment of vnet module IDs is not supported yet. A vnet module may specify a single prerequisite module at registration time by filling in the vmi_dependson field of its vnet_modinfo struct with the ID of the module it depends on. Unless specified otherwise, all vnet modules depend on VNET_MOD_NET (container for ifnet list head, rt_tables etc.), which thus has to and will always be initialized first. The framework will panic if it detects any unresolved dependencies before completing system initialization. Detection of unresolved dependencies for vnet modules registered after boot (kldloaded modules) is not provided. Note that the fact that each module can specify only a single prerequisite may become problematic in the long run. In particular, INET6 depends on INET being already instantiated, due to TCP / UDP structures residing in INET container. IPSEC also depends on INET, which will in turn additionally complicate making INET6-only kernel configs a reality. The entire registration framework can be compiled out by turning on the VIMAGE_GLOBALS kernel config option. Reviewed by: bz Approved by: julian (mentor)
831 lines
23 KiB
C
831 lines
23 KiB
C
/*-
|
|
* 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:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
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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
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* 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
|
|
* 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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|
*/
|
|
|
|
/*
|
|
* Ethernet address resolution protocol.
|
|
* TODO:
|
|
* add "inuse/lock" bit (or ref. count) along with valid bit
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|
*/
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|
|
|
#include <sys/cdefs.h>
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|
__FBSDID("$FreeBSD$");
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|
|
|
#include "opt_inet.h"
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|
#include "opt_route.h"
|
|
#include "opt_mac.h"
|
|
#include "opt_carp.h"
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|
|
|
#include <sys/param.h>
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|
#include <sys/kernel.h>
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|
#include <sys/queue.h>
|
|
#include <sys/sysctl.h>
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|
#include <sys/systm.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/syslog.h>
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|
#include <sys/vimage.h>
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|
|
|
#include <net/if.h>
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|
#include <net/if_dl.h>
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|
#include <net/if_types.h>
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|
#include <net/route.h>
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|
#include <net/netisr.h>
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|
#include <net/if_llc.h>
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|
#include <net/ethernet.h>
|
|
#include <net/vnet.h>
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|
|
|
#include <netinet/in.h>
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|
#include <netinet/in_var.h>
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|
#include <net/if_llatbl.h>
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|
#include <netinet/if_ether.h>
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|
#include <netinet/vinet.h>
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|
|
|
#include <net/if_arc.h>
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|
#include <net/iso88025.h>
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|
|
|
#ifdef DEV_CARP
|
|
#include <netinet/ip_carp.h>
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|
#endif
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|
|
|
#include <security/mac/mac_framework.h>
|
|
|
|
#define SIN(s) ((struct sockaddr_in *)s)
|
|
#define SDL(s) ((struct sockaddr_dl *)s)
|
|
#define LLTABLE(ifp) \
|
|
((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
|
|
|
|
SYSCTL_DECL(_net_link_ether);
|
|
SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
|
|
|
|
/* timer values */
|
|
#ifdef VIMAGE_GLOBALS
|
|
static int arpt_keep; /* once resolved, good for 20 more minutes */
|
|
static int arp_maxtries;
|
|
int useloopback; /* use loopback interface for local traffic */
|
|
static int arp_proxyall;
|
|
#endif
|
|
|
|
SYSCTL_V_INT(V_NET, vnet_inet, _net_link_ether_inet, OID_AUTO, max_age,
|
|
CTLFLAG_RW, arpt_keep, 0, "ARP entry lifetime in seconds");
|
|
|
|
static struct ifqueue arpintrq;
|
|
|
|
SYSCTL_V_INT(V_NET, vnet_inet, _net_link_ether_inet, OID_AUTO, maxtries,
|
|
CTLFLAG_RW, arp_maxtries, 0,
|
|
"ARP resolution attempts before returning error");
|
|
SYSCTL_V_INT(V_NET, vnet_inet, _net_link_ether_inet, OID_AUTO, useloopback,
|
|
CTLFLAG_RW, useloopback, 0,
|
|
"Use the loopback interface for local traffic");
|
|
SYSCTL_V_INT(V_NET, vnet_inet, _net_link_ether_inet, OID_AUTO, proxyall,
|
|
CTLFLAG_RW, arp_proxyall, 0,
|
|
"Enable proxy ARP for all suitable requests");
|
|
|
|
static void arp_init(void);
|
|
static int arp_iattach(const void *);
|
|
void arprequest(struct ifnet *,
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|
struct in_addr *, struct in_addr *, u_char *);
|
|
static void arpintr(struct mbuf *);
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|
static void arptimer(void *);
|
|
#ifdef INET
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|
static void in_arpinput(struct mbuf *);
|
|
#endif
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|
|
|
#ifndef VIMAGE_GLOBALS
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|
static const vnet_modinfo_t vnet_arp_modinfo = {
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|
.vmi_id = VNET_MOD_ARP,
|
|
.vmi_name = "arp",
|
|
.vmi_dependson = VNET_MOD_INET,
|
|
.vmi_iattach = arp_iattach
|
|
};
|
|
#endif /* !VIMAGE_GLOBALS */
|
|
|
|
#ifdef AF_INET
|
|
void arp_ifscrub(struct ifnet *ifp, uint32_t addr);
|
|
|
|
/*
|
|
* called by in_ifscrub to remove entry from the table when
|
|
* the interface goes away
|
|
*/
|
|
void
|
|
arp_ifscrub(struct ifnet *ifp, uint32_t addr)
|
|
{
|
|
struct sockaddr_in addr4;
|
|
|
|
bzero((void *)&addr4, sizeof(addr4));
|
|
addr4.sin_len = sizeof(addr4);
|
|
addr4.sin_family = AF_INET;
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|
addr4.sin_addr.s_addr = addr;
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|
IF_AFDATA_LOCK(ifp);
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|
lla_lookup(LLTABLE(ifp), (LLE_DELETE | LLE_IFADDR),
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|
(struct sockaddr *)&addr4);
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IF_AFDATA_UNLOCK(ifp);
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|
}
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|
#endif
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|
|
|
/*
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|
* Timeout routine. Age arp_tab entries periodically.
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|
*/
|
|
static void
|
|
arptimer(void *arg)
|
|
{
|
|
struct ifnet *ifp;
|
|
struct llentry *lle = (struct llentry *)arg;
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|
|
|
if (lle == NULL) {
|
|
panic("%s: NULL entry!\n", __func__);
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|
return;
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|
}
|
|
ifp = lle->lle_tbl->llt_ifp;
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|
IF_AFDATA_LOCK(ifp);
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|
LLE_WLOCK(lle);
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|
if (((lle->la_flags & LLE_DELETED)
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|| (time_second >= lle->la_expire))
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|
&& (!callout_pending(&lle->la_timer) &&
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|
callout_active(&lle->la_timer)))
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|
(void) llentry_free(lle);
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|
else {
|
|
/*
|
|
* Still valid, just drop our reference
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|
*/
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|
LLE_FREE_LOCKED(lle);
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|
}
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|
IF_AFDATA_UNLOCK(ifp);
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
*/
|
|
void
|
|
arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr *tip,
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|
u_char *enaddr)
|
|
{
|
|
struct mbuf *m;
|
|
struct arphdr *ah;
|
|
struct sockaddr sa;
|
|
|
|
if (sip == NULL) {
|
|
/* XXX don't believe this can happen (or explain why) */
|
|
/*
|
|
* The caller did not supply a source address, try to find
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|
* a compatible one among those assigned to this interface.
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|
*/
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|
struct ifaddr *ifa;
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|
|
|
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
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|
if (!ifa->ifa_addr ||
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|
ifa->ifa_addr->sa_family != AF_INET)
|
|
continue;
|
|
sip = &SIN(ifa->ifa_addr)->sin_addr;
|
|
if (0 == ((sip->s_addr ^ tip->s_addr) &
|
|
SIN(ifa->ifa_netmask)->sin_addr.s_addr) )
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|
break; /* found it. */
|
|
}
|
|
if (sip == NULL) {
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printf("%s: cannot find matching address\n", __func__);
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|
return;
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|
}
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|
}
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|
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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(*ah) + 2*sizeof(struct in_addr) +
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|
2*ifp->if_data.ifi_addrlen;
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|
m->m_pkthdr.len = m->m_len;
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MH_ALIGN(m, m->m_len);
|
|
ah = mtod(m, struct arphdr *);
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|
bzero((caddr_t)ah, m->m_len);
|
|
#ifdef MAC
|
|
mac_netinet_arp_send(ifp, m);
|
|
#endif
|
|
ah->ar_pro = htons(ETHERTYPE_IP);
|
|
ah->ar_hln = ifp->if_addrlen; /* hardware address length */
|
|
ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
|
|
ah->ar_op = htons(ARPOP_REQUEST);
|
|
bcopy((caddr_t)enaddr, (caddr_t)ar_sha(ah), ah->ar_hln);
|
|
bcopy((caddr_t)sip, (caddr_t)ar_spa(ah), ah->ar_pln);
|
|
bcopy((caddr_t)tip, (caddr_t)ar_tpa(ah), ah->ar_pln);
|
|
sa.sa_family = AF_ARP;
|
|
sa.sa_len = 2;
|
|
m->m_flags |= M_BCAST;
|
|
(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
|
|
}
|
|
|
|
/*
|
|
* Resolve an IP address into an ethernet address.
|
|
* On input:
|
|
* ifp is the interface we use
|
|
* rt0 is the route to the final destination (possibly useless)
|
|
* m is the mbuf. May be NULL if we don't have a packet.
|
|
* dst is the next hop,
|
|
* desten is where we want the address.
|
|
*
|
|
* On success, desten is filled in and the function returns 0;
|
|
* If the packet must be held pending resolution, we return EWOULDBLOCK
|
|
* On other errors, we return the corresponding error code.
|
|
* Note that m_freem() handles NULL.
|
|
*/
|
|
int
|
|
arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
|
|
struct sockaddr *dst, u_char *desten, struct llentry **lle)
|
|
{
|
|
INIT_VNET_INET(ifp->if_vnet);
|
|
struct llentry *la = 0;
|
|
u_int flags = 0;
|
|
int error, renew;
|
|
|
|
*lle = NULL;
|
|
if (m != NULL) {
|
|
if (m->m_flags & M_BCAST) {
|
|
/* broadcast */
|
|
(void)memcpy(desten,
|
|
ifp->if_broadcastaddr, ifp->if_addrlen);
|
|
return (0);
|
|
}
|
|
if (m->m_flags & M_MCAST && ifp->if_type != IFT_ARCNET) {
|
|
/* multicast */
|
|
ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
|
|
return (0);
|
|
}
|
|
}
|
|
/* XXXXX
|
|
*/
|
|
retry:
|
|
IF_AFDATA_RLOCK(ifp);
|
|
la = lla_lookup(LLTABLE(ifp), flags, dst);
|
|
IF_AFDATA_RUNLOCK(ifp);
|
|
if ((la == NULL) && ((flags & LLE_EXCLUSIVE) == 0)
|
|
&& ((ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) == 0)) {
|
|
flags |= (LLE_CREATE | LLE_EXCLUSIVE);
|
|
IF_AFDATA_WLOCK(ifp);
|
|
la = lla_lookup(LLTABLE(ifp), flags, dst);
|
|
IF_AFDATA_WUNLOCK(ifp);
|
|
}
|
|
if (la == NULL) {
|
|
if (flags & LLE_CREATE)
|
|
log(LOG_DEBUG,
|
|
"arpresolve: can't allocate llinfo for %s\n",
|
|
inet_ntoa(SIN(dst)->sin_addr));
|
|
m_freem(m);
|
|
return (EINVAL);
|
|
}
|
|
|
|
if ((la->la_flags & LLE_VALID) &&
|
|
((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime)) {
|
|
bcopy(&la->ll_addr, desten, ifp->if_addrlen);
|
|
/*
|
|
* If entry has an expiry time and it is approaching,
|
|
* see if we need to send an ARP request within this
|
|
* arpt_down interval.
|
|
*/
|
|
if (!(la->la_flags & LLE_STATIC) &&
|
|
time_uptime + la->la_preempt > la->la_expire) {
|
|
arprequest(ifp, NULL,
|
|
&SIN(dst)->sin_addr, IF_LLADDR(ifp));
|
|
|
|
la->la_preempt--;
|
|
}
|
|
|
|
*lle = la;
|
|
error = 0;
|
|
goto done;
|
|
}
|
|
|
|
if (la->la_flags & LLE_STATIC) { /* should not happen! */
|
|
log(LOG_DEBUG, "arpresolve: ouch, empty static llinfo for %s\n",
|
|
inet_ntoa(SIN(dst)->sin_addr));
|
|
m_freem(m);
|
|
error = EINVAL;
|
|
goto done;
|
|
}
|
|
|
|
renew = (la->la_asked == 0 || la->la_expire != time_uptime);
|
|
if ((renew || m != NULL) && (flags & LLE_EXCLUSIVE) == 0) {
|
|
flags |= LLE_EXCLUSIVE;
|
|
LLE_RUNLOCK(la);
|
|
goto retry;
|
|
}
|
|
/*
|
|
* There is an arptab entry, but no ethernet address
|
|
* response yet. Replace the held mbuf with this
|
|
* latest one.
|
|
*/
|
|
if (m != NULL) {
|
|
if (la->la_hold != NULL)
|
|
m_freem(la->la_hold);
|
|
la->la_hold = m;
|
|
if (renew == 0 && (flags & LLE_EXCLUSIVE)) {
|
|
flags &= ~LLE_EXCLUSIVE;
|
|
LLE_DOWNGRADE(la);
|
|
}
|
|
|
|
}
|
|
/*
|
|
* Return EWOULDBLOCK if we have tried less than arp_maxtries. It
|
|
* will be masked by ether_output(). Return EHOSTDOWN/EHOSTUNREACH
|
|
* if we have already sent arp_maxtries ARP requests. Retransmit the
|
|
* ARP request, but not faster than one request per second.
|
|
*/
|
|
if (la->la_asked < V_arp_maxtries)
|
|
error = EWOULDBLOCK; /* First request. */
|
|
else
|
|
error =
|
|
(rt0->rt_flags & RTF_GATEWAY) ? EHOSTDOWN : EHOSTUNREACH;
|
|
|
|
if (renew) {
|
|
LLE_ADDREF(la);
|
|
la->la_expire = time_uptime;
|
|
callout_reset(&la->la_timer, hz, arptimer, la);
|
|
la->la_asked++;
|
|
LLE_WUNLOCK(la);
|
|
arprequest(ifp, NULL, &SIN(dst)->sin_addr,
|
|
IF_LLADDR(ifp));
|
|
return (error);
|
|
}
|
|
done:
|
|
if (flags & LLE_EXCLUSIVE)
|
|
LLE_WUNLOCK(la);
|
|
else
|
|
LLE_RUNLOCK(la);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Common length and type checks are done here,
|
|
* then the protocol-specific routine is called.
|
|
*/
|
|
static void
|
|
arpintr(struct mbuf *m)
|
|
{
|
|
struct arphdr *ar;
|
|
|
|
if (m->m_len < sizeof(struct arphdr) &&
|
|
((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) {
|
|
log(LOG_ERR, "arp: runt packet -- m_pullup failed\n");
|
|
return;
|
|
}
|
|
ar = mtod(m, struct arphdr *);
|
|
|
|
if (ntohs(ar->ar_hrd) != ARPHRD_ETHER &&
|
|
ntohs(ar->ar_hrd) != ARPHRD_IEEE802 &&
|
|
ntohs(ar->ar_hrd) != ARPHRD_ARCNET &&
|
|
ntohs(ar->ar_hrd) != ARPHRD_IEEE1394) {
|
|
log(LOG_ERR, "arp: unknown hardware address format (0x%2D)\n",
|
|
(unsigned char *)&ar->ar_hrd, "");
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
|
|
if (m->m_len < arphdr_len(ar)) {
|
|
if ((m = m_pullup(m, arphdr_len(ar))) == NULL) {
|
|
log(LOG_ERR, "arp: runt packet\n");
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
ar = mtod(m, struct arphdr *);
|
|
}
|
|
|
|
switch (ntohs(ar->ar_pro)) {
|
|
#ifdef INET
|
|
case ETHERTYPE_IP:
|
|
in_arpinput(m);
|
|
return;
|
|
#endif
|
|
}
|
|
m_freem(m);
|
|
}
|
|
|
|
#ifdef INET
|
|
/*
|
|
* ARP for Internet protocols on 10 Mb/s Ethernet.
|
|
* Algorithm is that given in RFC 826.
|
|
* In addition, a sanity check is performed on the sender
|
|
* protocol address, to catch impersonators.
|
|
* We no longer handle negotiations for use of trailer protocol:
|
|
* Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
|
|
* along with IP replies if we wanted trailers sent to us,
|
|
* and also sent them in response to IP replies.
|
|
* This allowed either end to announce the desire to receive
|
|
* trailer packets.
|
|
* We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
|
|
* but formerly didn't normally send requests.
|
|
*/
|
|
static int log_arp_wrong_iface = 1;
|
|
static int log_arp_movements = 1;
|
|
static int log_arp_permanent_modify = 1;
|
|
|
|
SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW,
|
|
&log_arp_wrong_iface, 0,
|
|
"log arp packets arriving on the wrong interface");
|
|
SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_movements, CTLFLAG_RW,
|
|
&log_arp_movements, 0,
|
|
"log arp replies from MACs different than the one in the cache");
|
|
SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_permanent_modify, CTLFLAG_RW,
|
|
&log_arp_permanent_modify, 0,
|
|
"log arp replies from MACs different than the one in the permanent arp entry");
|
|
|
|
|
|
static void
|
|
in_arpinput(struct mbuf *m)
|
|
{
|
|
struct arphdr *ah;
|
|
struct ifnet *ifp = m->m_pkthdr.rcvif;
|
|
struct llentry *la = NULL;
|
|
struct rtentry *rt;
|
|
struct ifaddr *ifa;
|
|
struct in_ifaddr *ia;
|
|
struct sockaddr sa;
|
|
struct in_addr isaddr, itaddr, myaddr;
|
|
u_int8_t *enaddr = NULL;
|
|
int op, flags;
|
|
struct mbuf *m0;
|
|
int req_len;
|
|
int bridged = 0, is_bridge = 0;
|
|
#ifdef DEV_CARP
|
|
int carp_match = 0;
|
|
#endif
|
|
struct sockaddr_in sin;
|
|
sin.sin_len = sizeof(struct sockaddr_in);
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_addr.s_addr = 0;
|
|
INIT_VNET_INET(ifp->if_vnet);
|
|
|
|
if (ifp->if_bridge)
|
|
bridged = 1;
|
|
if (ifp->if_type == IFT_BRIDGE)
|
|
is_bridge = 1;
|
|
|
|
req_len = arphdr_len2(ifp->if_addrlen, sizeof(struct in_addr));
|
|
if (m->m_len < req_len && (m = m_pullup(m, req_len)) == NULL) {
|
|
log(LOG_ERR, "in_arp: runt packet -- m_pullup failed\n");
|
|
return;
|
|
}
|
|
|
|
ah = mtod(m, struct arphdr *);
|
|
op = ntohs(ah->ar_op);
|
|
(void)memcpy(&isaddr, ar_spa(ah), sizeof (isaddr));
|
|
(void)memcpy(&itaddr, ar_tpa(ah), sizeof (itaddr));
|
|
|
|
/*
|
|
* For a bridge, we want to check the address irrespective
|
|
* of the receive interface. (This will change slightly
|
|
* when we have clusters of interfaces).
|
|
* If the interface does not match, but the recieving interface
|
|
* is part of carp, we call carp_iamatch to see if this is a
|
|
* request for the virtual host ip.
|
|
* XXX: This is really ugly!
|
|
*/
|
|
LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) {
|
|
if (((bridged && ia->ia_ifp->if_bridge != NULL) ||
|
|
ia->ia_ifp == ifp) &&
|
|
itaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
|
|
goto match;
|
|
#ifdef DEV_CARP
|
|
if (ifp->if_carp != NULL &&
|
|
carp_iamatch(ifp->if_carp, ia, &isaddr, &enaddr) &&
|
|
itaddr.s_addr == ia->ia_addr.sin_addr.s_addr) {
|
|
carp_match = 1;
|
|
goto match;
|
|
}
|
|
#endif
|
|
}
|
|
LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash)
|
|
if (((bridged && ia->ia_ifp->if_bridge != NULL) ||
|
|
ia->ia_ifp == ifp) &&
|
|
isaddr.s_addr == ia->ia_addr.sin_addr.s_addr)
|
|
goto match;
|
|
|
|
#define BDG_MEMBER_MATCHES_ARP(addr, ifp, ia) \
|
|
(ia->ia_ifp->if_bridge == ifp->if_softc && \
|
|
!bcmp(IF_LLADDR(ia->ia_ifp), IF_LLADDR(ifp), ifp->if_addrlen) && \
|
|
addr == ia->ia_addr.sin_addr.s_addr)
|
|
/*
|
|
* Check the case when bridge shares its MAC address with
|
|
* some of its children, so packets are claimed by bridge
|
|
* itself (bridge_input() does it first), but they are really
|
|
* meant to be destined to the bridge member.
|
|
*/
|
|
if (is_bridge) {
|
|
LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) {
|
|
if (BDG_MEMBER_MATCHES_ARP(itaddr.s_addr, ifp, ia)) {
|
|
ifp = ia->ia_ifp;
|
|
goto match;
|
|
}
|
|
}
|
|
}
|
|
#undef BDG_MEMBER_MATCHES_ARP
|
|
|
|
/*
|
|
* No match, use the first inet address on the receive interface
|
|
* as a dummy address for the rest of the function.
|
|
*/
|
|
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
|
|
if (ifa->ifa_addr->sa_family == AF_INET) {
|
|
ia = ifatoia(ifa);
|
|
goto match;
|
|
}
|
|
/*
|
|
* If bridging, fall back to using any inet address.
|
|
*/
|
|
if (!bridged || (ia = TAILQ_FIRST(&V_in_ifaddrhead)) == NULL)
|
|
goto drop;
|
|
match:
|
|
if (!enaddr)
|
|
enaddr = (u_int8_t *)IF_LLADDR(ifp);
|
|
myaddr = ia->ia_addr.sin_addr;
|
|
if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen))
|
|
goto drop; /* it's from me, ignore it. */
|
|
if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
|
|
log(LOG_ERR,
|
|
"arp: link address is broadcast for IP address %s!\n",
|
|
inet_ntoa(isaddr));
|
|
goto drop;
|
|
}
|
|
/*
|
|
* Warn if another host is using the same IP address, but only if the
|
|
* IP address isn't 0.0.0.0, which is used for DHCP only, in which
|
|
* case we suppress the warning to avoid false positive complaints of
|
|
* potential misconfiguration.
|
|
*/
|
|
if (!bridged && isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) {
|
|
log(LOG_ERR,
|
|
"arp: %*D is using my IP address %s on %s!\n",
|
|
ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
|
|
inet_ntoa(isaddr), ifp->if_xname);
|
|
itaddr = myaddr;
|
|
goto reply;
|
|
}
|
|
if (ifp->if_flags & IFF_STATICARP)
|
|
goto reply;
|
|
|
|
bzero(&sin, sizeof(sin));
|
|
sin.sin_len = sizeof(struct sockaddr_in);
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_addr = isaddr;
|
|
flags = (itaddr.s_addr == myaddr.s_addr) ? LLE_CREATE : 0;
|
|
flags |= LLE_EXCLUSIVE;
|
|
IF_AFDATA_LOCK(ifp);
|
|
la = lla_lookup(LLTABLE(ifp), flags, (struct sockaddr *)&sin);
|
|
IF_AFDATA_UNLOCK(ifp);
|
|
if (la != NULL) {
|
|
/* the following is not an error when doing bridging */
|
|
if (!bridged && la->lle_tbl->llt_ifp != ifp
|
|
#ifdef DEV_CARP
|
|
&& (ifp->if_type != IFT_CARP || !carp_match)
|
|
#endif
|
|
) {
|
|
if (log_arp_wrong_iface)
|
|
log(LOG_ERR, "arp: %s is on %s "
|
|
"but got reply from %*D on %s\n",
|
|
inet_ntoa(isaddr),
|
|
la->lle_tbl->llt_ifp->if_xname,
|
|
ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
|
|
ifp->if_xname);
|
|
goto reply;
|
|
}
|
|
if ((la->la_flags & LLE_VALID) &&
|
|
bcmp(ar_sha(ah), &la->ll_addr, ifp->if_addrlen)) {
|
|
if (la->la_flags & LLE_STATIC) {
|
|
log(LOG_ERR,
|
|
"arp: %*D attempts to modify permanent "
|
|
"entry for %s on %s\n",
|
|
ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
|
|
inet_ntoa(isaddr), ifp->if_xname);
|
|
goto reply;
|
|
}
|
|
if (log_arp_movements) {
|
|
log(LOG_INFO, "arp: %s moved from %*D "
|
|
"to %*D on %s\n",
|
|
inet_ntoa(isaddr),
|
|
ifp->if_addrlen,
|
|
(u_char *)&la->ll_addr, ":",
|
|
ifp->if_addrlen, (u_char *)ar_sha(ah), ":",
|
|
ifp->if_xname);
|
|
}
|
|
}
|
|
|
|
if (ifp->if_addrlen != ah->ar_hln) {
|
|
log(LOG_WARNING,
|
|
"arp from %*D: addr len: new %d, i/f %d (ignored)",
|
|
ifp->if_addrlen, (u_char *) ar_sha(ah), ":",
|
|
ah->ar_hln, ifp->if_addrlen);
|
|
goto reply;
|
|
}
|
|
(void)memcpy(&la->ll_addr, ar_sha(ah), ifp->if_addrlen);
|
|
la->la_flags |= LLE_VALID;
|
|
|
|
if (!(la->la_flags & LLE_STATIC)) {
|
|
la->la_expire = time_uptime + V_arpt_keep;
|
|
callout_reset(&la->la_timer, hz * V_arpt_keep,
|
|
arptimer, la);
|
|
}
|
|
la->la_asked = 0;
|
|
la->la_preempt = V_arp_maxtries;
|
|
if (la->la_hold != NULL) {
|
|
m0 = la->la_hold;
|
|
la->la_hold = 0;
|
|
memcpy(&sa, L3_ADDR(la), sizeof(sa));
|
|
LLE_WUNLOCK(la);
|
|
|
|
(*ifp->if_output)(ifp, m0, &sa, NULL);
|
|
return;
|
|
}
|
|
}
|
|
reply:
|
|
if (op != ARPOP_REQUEST)
|
|
goto drop;
|
|
|
|
if (itaddr.s_addr == myaddr.s_addr) {
|
|
/* Shortcut.. the receiving interface is the target. */
|
|
(void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
|
|
(void)memcpy(ar_sha(ah), enaddr, ah->ar_hln);
|
|
} else {
|
|
struct llentry *lle = NULL;
|
|
|
|
if (!V_arp_proxyall)
|
|
goto drop;
|
|
|
|
sin.sin_addr = itaddr;
|
|
/* XXX MRT use table 0 for arp reply */
|
|
rt = in_rtalloc1((struct sockaddr *)&sin, 0, 0UL, 0);
|
|
if (!rt)
|
|
goto drop;
|
|
|
|
/*
|
|
* 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 || rt->rt_ifp == ifp) {
|
|
RTFREE_LOCKED(rt);
|
|
goto drop;
|
|
}
|
|
IF_AFDATA_LOCK(rt->rt_ifp);
|
|
lle = lla_lookup(LLTABLE(rt->rt_ifp), 0, (struct sockaddr *)&sin);
|
|
IF_AFDATA_UNLOCK(rt->rt_ifp);
|
|
RTFREE_LOCKED(rt);
|
|
|
|
if (lle != NULL) {
|
|
(void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln);
|
|
(void)memcpy(ar_sha(ah), &lle->ll_addr, ah->ar_hln);
|
|
LLE_RUNLOCK(lle);
|
|
} else
|
|
goto drop;
|
|
|
|
/*
|
|
* Also check that the node which sent the ARP packet
|
|
* is on the the interface we expect it to be on. This
|
|
* avoids ARP chaos if an interface is connected to the
|
|
* wrong network.
|
|
*/
|
|
sin.sin_addr = isaddr;
|
|
|
|
/* XXX MRT use table 0 for arp checks */
|
|
rt = in_rtalloc1((struct sockaddr *)&sin, 0, 0UL, 0);
|
|
if (!rt)
|
|
goto drop;
|
|
if (rt->rt_ifp != ifp) {
|
|
log(LOG_INFO, "arp_proxy: ignoring request"
|
|
" from %s via %s, expecting %s\n",
|
|
inet_ntoa(isaddr), ifp->if_xname,
|
|
rt->rt_ifp->if_xname);
|
|
RTFREE_LOCKED(rt);
|
|
goto drop;
|
|
}
|
|
RTFREE_LOCKED(rt);
|
|
|
|
#ifdef DEBUG_PROXY
|
|
printf("arp: proxying for %s\n",
|
|
inet_ntoa(itaddr));
|
|
#endif
|
|
}
|
|
|
|
if (la != NULL)
|
|
LLE_WUNLOCK(la);
|
|
if (itaddr.s_addr == myaddr.s_addr &&
|
|
IN_LINKLOCAL(ntohl(itaddr.s_addr))) {
|
|
/* RFC 3927 link-local IPv4; always reply by broadcast. */
|
|
#ifdef DEBUG_LINKLOCAL
|
|
printf("arp: sending reply for link-local addr %s\n",
|
|
inet_ntoa(itaddr));
|
|
#endif
|
|
m->m_flags |= M_BCAST;
|
|
m->m_flags &= ~M_MCAST;
|
|
} else {
|
|
/* default behaviour; never reply by broadcast. */
|
|
m->m_flags &= ~(M_BCAST|M_MCAST);
|
|
}
|
|
(void)memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
|
|
(void)memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
|
|
ah->ar_op = htons(ARPOP_REPLY);
|
|
ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
|
|
m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln);
|
|
m->m_pkthdr.len = m->m_len;
|
|
sa.sa_family = AF_ARP;
|
|
sa.sa_len = 2;
|
|
(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
|
|
return;
|
|
|
|
drop:
|
|
if (la != NULL)
|
|
LLE_WUNLOCK(la);
|
|
m_freem(m);
|
|
}
|
|
#endif
|
|
|
|
void
|
|
arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
|
|
{
|
|
struct llentry *lle;
|
|
|
|
if (ntohl(IA_SIN(ifa)->sin_addr.s_addr) != INADDR_ANY) {
|
|
arprequest(ifp, &IA_SIN(ifa)->sin_addr,
|
|
&IA_SIN(ifa)->sin_addr, IF_LLADDR(ifp));
|
|
/*
|
|
* interface address is considered static entry
|
|
* because the output of the arp utility shows
|
|
* that L2 entry as permanent
|
|
*/
|
|
IF_AFDATA_LOCK(ifp);
|
|
lle = lla_lookup(LLTABLE(ifp), (LLE_CREATE | LLE_IFADDR | LLE_STATIC),
|
|
(struct sockaddr *)IA_SIN(ifa));
|
|
IF_AFDATA_UNLOCK(ifp);
|
|
if (lle == NULL)
|
|
log(LOG_INFO, "arp_ifinit: cannot create arp "
|
|
"entry for interface address\n");
|
|
else
|
|
LLE_RUNLOCK(lle);
|
|
}
|
|
ifa->ifa_rtrequest = NULL;
|
|
}
|
|
|
|
void
|
|
arp_ifinit2(struct ifnet *ifp, struct ifaddr *ifa, u_char *enaddr)
|
|
{
|
|
if (ntohl(IA_SIN(ifa)->sin_addr.s_addr) != INADDR_ANY)
|
|
arprequest(ifp, &IA_SIN(ifa)->sin_addr,
|
|
&IA_SIN(ifa)->sin_addr, enaddr);
|
|
ifa->ifa_rtrequest = NULL;
|
|
}
|
|
|
|
static int
|
|
arp_iattach(const void *unused __unused)
|
|
{
|
|
INIT_VNET_INET(curvnet);
|
|
|
|
V_arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
|
|
V_arp_maxtries = 5;
|
|
V_useloopback = 1; /* use loopback interface for local traffic */
|
|
V_arp_proxyall = 0;
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
arp_init(void)
|
|
{
|
|
|
|
#ifndef VIMAGE_GLOBALS
|
|
vnet_mod_register(&vnet_arp_modinfo);
|
|
#else
|
|
arp_iattach(NULL);
|
|
#endif
|
|
|
|
arpintrq.ifq_maxlen = 50;
|
|
mtx_init(&arpintrq.ifq_mtx, "arp_inq", NULL, MTX_DEF);
|
|
netisr_register(NETISR_ARP, arpintr, &arpintrq, 0);
|
|
}
|
|
SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);
|