freebsd-dev/sys/netinet/in.c
2023-04-25 10:59:50 +00:00

1854 lines
48 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (C) 2001 WIDE Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* 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.
* 3. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* 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)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)in.c 8.4 (Berkeley) 1/9/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#define IN_HISTORICAL_NETS /* include class masks */
#include <sys/param.h>
#include <sys/eventhandler.h>
#include <sys/systm.h>
#include <sys/sockio.h>
#include <sys/malloc.h>
#include <sys/priv.h>
#include <sys/socket.h>
#include <sys/jail.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/sx.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_arp.h>
#include <net/if_dl.h>
#include <net/if_llatbl.h>
#include <net/if_private.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/route/nhop.h>
#include <net/route/route_ctl.h>
#include <net/vnet.h>
#include <netinet/if_ether.h>
#include <netinet/in.h>
#include <netinet/in_fib.h>
#include <netinet/in_var.h>
#include <netinet/in_pcb.h>
#include <netinet/ip_var.h>
#include <netinet/ip_carp.h>
#include <netinet/igmp_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
static int in_aifaddr_ioctl(u_long, caddr_t, struct ifnet *, struct ucred *);
static int in_difaddr_ioctl(u_long, caddr_t, struct ifnet *, struct ucred *);
static int in_gifaddr_ioctl(u_long, caddr_t, struct ifnet *, struct ucred *);
static void in_socktrim(struct sockaddr_in *);
static void in_purgemaddrs(struct ifnet *);
static bool ia_need_loopback_route(const struct in_ifaddr *);
VNET_DEFINE_STATIC(int, nosameprefix);
#define V_nosameprefix VNET(nosameprefix)
SYSCTL_INT(_net_inet_ip, OID_AUTO, no_same_prefix, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(nosameprefix), 0,
"Refuse to create same prefixes on different interfaces");
VNET_DEFINE_STATIC(bool, broadcast_lowest);
#define V_broadcast_lowest VNET(broadcast_lowest)
SYSCTL_BOOL(_net_inet_ip, OID_AUTO, broadcast_lowest, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(broadcast_lowest), 0,
"Treat lowest address on a subnet (host 0) as broadcast");
VNET_DEFINE(bool, ip_allow_net240) = false;
#define V_ip_allow_net240 VNET(ip_allow_net240)
SYSCTL_BOOL(_net_inet_ip, OID_AUTO, allow_net240,
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip_allow_net240), 0,
"Allow use of Experimental addresses, aka Class E (240/4)");
/* see https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-240 */
VNET_DEFINE(bool, ip_allow_net0) = false;
SYSCTL_BOOL(_net_inet_ip, OID_AUTO, allow_net0,
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip_allow_net0), 0,
"Allow use of addresses in network 0/8");
/* see https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-0 */
VNET_DEFINE(uint32_t, in_loopback_mask) = IN_LOOPBACK_MASK_DFLT;
#define V_in_loopback_mask VNET(in_loopback_mask)
static int sysctl_loopback_prefixlen(SYSCTL_HANDLER_ARGS);
SYSCTL_PROC(_net_inet_ip, OID_AUTO, loopback_prefixlen,
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW,
NULL, 0, sysctl_loopback_prefixlen, "I",
"Prefix length of address space reserved for loopback");
/* see https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-127 */
VNET_DECLARE(struct inpcbinfo, ripcbinfo);
#define V_ripcbinfo VNET(ripcbinfo)
static struct sx in_control_sx;
SX_SYSINIT(in_control_sx, &in_control_sx, "in_control");
/*
* Return 1 if an internet address is for a ``local'' host
* (one to which we have a connection).
*/
int
in_localaddr(struct in_addr in)
{
u_long i = ntohl(in.s_addr);
struct in_ifaddr *ia;
NET_EPOCH_ASSERT();
CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
if ((i & ia->ia_subnetmask) == ia->ia_subnet)
return (1);
}
return (0);
}
/*
* Return 1 if an internet address is for the local host and configured
* on one of its interfaces.
*/
bool
in_localip(struct in_addr in)
{
struct in_ifaddr *ia;
NET_EPOCH_ASSERT();
CK_LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash)
if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr)
return (true);
return (false);
}
/*
* Like in_localip(), but FIB-aware.
*/
bool
in_localip_fib(struct in_addr in, uint16_t fib)
{
struct in_ifaddr *ia;
NET_EPOCH_ASSERT();
CK_LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash)
if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr &&
ia->ia_ifa.ifa_ifp->if_fib == fib)
return (true);
return (false);
}
/*
* Return 1 if an internet address is configured on an interface.
*/
int
in_ifhasaddr(struct ifnet *ifp, struct in_addr in)
{
struct ifaddr *ifa;
struct in_ifaddr *ia;
NET_EPOCH_ASSERT();
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
ia = (struct in_ifaddr *)ifa;
if (ia->ia_addr.sin_addr.s_addr == in.s_addr)
return (1);
}
return (0);
}
/*
* Return a reference to the interface address which is different to
* the supplied one but with same IP address value.
*/
static struct in_ifaddr *
in_localip_more(struct in_ifaddr *original_ia)
{
struct epoch_tracker et;
in_addr_t original_addr = IA_SIN(original_ia)->sin_addr.s_addr;
uint32_t original_fib = original_ia->ia_ifa.ifa_ifp->if_fib;
struct in_ifaddr *ia;
NET_EPOCH_ENTER(et);
CK_LIST_FOREACH(ia, INADDR_HASH(original_addr), ia_hash) {
in_addr_t addr = IA_SIN(ia)->sin_addr.s_addr;
uint32_t fib = ia->ia_ifa.ifa_ifp->if_fib;
if (!V_rt_add_addr_allfibs && (original_fib != fib))
continue;
if ((original_ia != ia) && (original_addr == addr)) {
ifa_ref(&ia->ia_ifa);
NET_EPOCH_EXIT(et);
return (ia);
}
}
NET_EPOCH_EXIT(et);
return (NULL);
}
/*
* Tries to find first IPv4 address in the provided fib.
* Prefers non-loopback addresses and return loopback IFF
* @loopback_ok is set.
*
* Returns ifa or NULL.
*/
struct in_ifaddr *
in_findlocal(uint32_t fibnum, bool loopback_ok)
{
struct in_ifaddr *ia = NULL, *ia_lo = NULL;
NET_EPOCH_ASSERT();
CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
uint32_t ia_fib = ia->ia_ifa.ifa_ifp->if_fib;
if (!V_rt_add_addr_allfibs && (fibnum != ia_fib))
continue;
if (!IN_LOOPBACK(ntohl(IA_SIN(ia)->sin_addr.s_addr)))
break;
if (loopback_ok)
ia_lo = ia;
}
if (ia == NULL)
ia = ia_lo;
return (ia);
}
/*
* Determine whether an IP address is in a reserved set of addresses
* that may not be forwarded, or whether datagrams to that destination
* may be forwarded.
*/
int
in_canforward(struct in_addr in)
{
u_long i = ntohl(in.s_addr);
if (IN_MULTICAST(i) || IN_LINKLOCAL(i) || IN_LOOPBACK(i))
return (0);
if (IN_EXPERIMENTAL(i) && !V_ip_allow_net240)
return (0);
if (IN_ZERONET(i) && !V_ip_allow_net0)
return (0);
return (1);
}
/*
* Sysctl to manage prefix of reserved loopback network; translate
* to/from mask. The mask is always contiguous high-order 1 bits
* followed by all 0 bits.
*/
static int
sysctl_loopback_prefixlen(SYSCTL_HANDLER_ARGS)
{
int error, preflen;
/* ffs is 1-based; compensate. */
preflen = 33 - ffs(V_in_loopback_mask);
error = sysctl_handle_int(oidp, &preflen, 0, req);
if (error || !req->newptr)
return (error);
if (preflen < 8 || preflen > 31)
return (EINVAL);
V_in_loopback_mask = 0xffffffff << (32 - preflen);
return (0);
}
/*
* Trim a mask in a sockaddr
*/
static void
in_socktrim(struct sockaddr_in *ap)
{
char *cplim = (char *) &ap->sin_addr;
char *cp = (char *) (&ap->sin_addr + 1);
ap->sin_len = 0;
while (--cp >= cplim)
if (*cp) {
(ap)->sin_len = cp - (char *) (ap) + 1;
break;
}
}
/*
* Generic internet control operations (ioctl's).
*/
int
in_control(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
struct thread *td)
{
struct ifreq *ifr = (struct ifreq *)data;
struct sockaddr_in *addr = (struct sockaddr_in *)&ifr->ifr_addr;
struct epoch_tracker et;
struct ifaddr *ifa;
struct in_ifaddr *ia;
int error;
if (ifp == NULL)
return (EADDRNOTAVAIL);
struct ucred *cred = (td != NULL) ? td->td_ucred : NULL;
/*
* Filter out 4 ioctls we implement directly. Forward the rest
* to specific functions and ifp->if_ioctl().
*/
switch (cmd) {
case SIOCGIFADDR:
case SIOCGIFBRDADDR:
case SIOCGIFDSTADDR:
case SIOCGIFNETMASK:
break;
case SIOCGIFALIAS:
sx_xlock(&in_control_sx);
error = in_gifaddr_ioctl(cmd, data, ifp, cred);
sx_xunlock(&in_control_sx);
return (error);
case SIOCDIFADDR:
sx_xlock(&in_control_sx);
error = in_difaddr_ioctl(cmd, data, ifp, cred);
sx_xunlock(&in_control_sx);
return (error);
case OSIOCAIFADDR: /* 9.x compat */
case SIOCAIFADDR:
sx_xlock(&in_control_sx);
error = in_aifaddr_ioctl(cmd, data, ifp, cred);
sx_xunlock(&in_control_sx);
return (error);
case SIOCSIFADDR:
case SIOCSIFBRDADDR:
case SIOCSIFDSTADDR:
case SIOCSIFNETMASK:
/* We no longer support that old commands. */
return (EINVAL);
default:
if (ifp->if_ioctl == NULL)
return (EOPNOTSUPP);
return ((*ifp->if_ioctl)(ifp, cmd, data));
}
if (addr->sin_addr.s_addr != INADDR_ANY &&
prison_check_ip4(cred, &addr->sin_addr) != 0)
return (EADDRNOTAVAIL);
/*
* Find address for this interface, if it exists. If an
* address was specified, find that one instead of the
* first one on the interface, if possible.
*/
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
ia = (struct in_ifaddr *)ifa;
if (ia->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr)
break;
}
if (ifa == NULL)
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
if (ifa->ifa_addr->sa_family == AF_INET) {
ia = (struct in_ifaddr *)ifa;
if (prison_check_ip4(cred,
&ia->ia_addr.sin_addr) == 0)
break;
}
if (ifa == NULL) {
NET_EPOCH_EXIT(et);
return (EADDRNOTAVAIL);
}
error = 0;
switch (cmd) {
case SIOCGIFADDR:
*addr = ia->ia_addr;
break;
case SIOCGIFBRDADDR:
if ((ifp->if_flags & IFF_BROADCAST) == 0) {
error = EINVAL;
break;
}
*addr = ia->ia_broadaddr;
break;
case SIOCGIFDSTADDR:
if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
error = EINVAL;
break;
}
*addr = ia->ia_dstaddr;
break;
case SIOCGIFNETMASK:
*addr = ia->ia_sockmask;
break;
}
NET_EPOCH_EXIT(et);
return (error);
}
static int
in_aifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct ucred *cred)
{
const struct in_aliasreq *ifra = (struct in_aliasreq *)data;
const struct sockaddr_in *addr = &ifra->ifra_addr;
const struct sockaddr_in *broadaddr = &ifra->ifra_broadaddr;
const struct sockaddr_in *mask = &ifra->ifra_mask;
const struct sockaddr_in *dstaddr = &ifra->ifra_dstaddr;
const int vhid = (cmd == SIOCAIFADDR) ? ifra->ifra_vhid : 0;
struct epoch_tracker et;
struct ifaddr *ifa;
struct in_ifaddr *ia;
bool iaIsFirst;
int error = 0;
error = priv_check_cred(cred, PRIV_NET_ADDIFADDR);
if (error)
return (error);
/*
* ifra_addr must be present and be of INET family.
* ifra_broadaddr/ifra_dstaddr and ifra_mask are optional.
*/
if (addr->sin_len != sizeof(struct sockaddr_in) ||
addr->sin_family != AF_INET)
return (EINVAL);
if (broadaddr->sin_len != 0 &&
(broadaddr->sin_len != sizeof(struct sockaddr_in) ||
broadaddr->sin_family != AF_INET))
return (EINVAL);
if (mask->sin_len != 0 &&
(mask->sin_len != sizeof(struct sockaddr_in) ||
mask->sin_family != AF_INET))
return (EINVAL);
if ((ifp->if_flags & IFF_POINTOPOINT) &&
(dstaddr->sin_len != sizeof(struct sockaddr_in) ||
dstaddr->sin_addr.s_addr == INADDR_ANY))
return (EDESTADDRREQ);
if (vhid != 0 && carp_attach_p == NULL)
return (EPROTONOSUPPORT);
/*
* See whether address already exist.
*/
iaIsFirst = true;
ia = NULL;
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
struct in_ifaddr *it;
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
it = (struct in_ifaddr *)ifa;
if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr &&
prison_check_ip4(cred, &addr->sin_addr) == 0)
ia = it;
else
iaIsFirst = false;
}
NET_EPOCH_EXIT(et);
if (ia != NULL)
(void )in_difaddr_ioctl(cmd, data, ifp, cred);
ifa = ifa_alloc(sizeof(struct in_ifaddr), M_WAITOK);
ia = (struct in_ifaddr *)ifa;
ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
callout_init_rw(&ia->ia_garp_timer, &ifp->if_addr_lock,
CALLOUT_RETURNUNLOCKED);
ia->ia_ifp = ifp;
ia->ia_addr = *addr;
if (mask->sin_len != 0) {
ia->ia_sockmask = *mask;
ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
} else {
in_addr_t i = ntohl(addr->sin_addr.s_addr);
/*
* If netmask isn't supplied, use historical default.
* This is deprecated for interfaces other than loopback
* or point-to-point; warn in other cases. In the future
* we should return an error rather than warning.
*/
if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0)
printf("%s: set address: WARNING: network mask "
"should be specified; using historical default\n",
ifp->if_xname);
if (IN_CLASSA(i))
ia->ia_subnetmask = IN_CLASSA_NET;
else if (IN_CLASSB(i))
ia->ia_subnetmask = IN_CLASSB_NET;
else
ia->ia_subnetmask = IN_CLASSC_NET;
ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
}
ia->ia_subnet = ntohl(addr->sin_addr.s_addr) & ia->ia_subnetmask;
in_socktrim(&ia->ia_sockmask);
if (ifp->if_flags & IFF_BROADCAST) {
if (broadaddr->sin_len != 0) {
ia->ia_broadaddr = *broadaddr;
} else if (ia->ia_subnetmask == IN_RFC3021_MASK) {
ia->ia_broadaddr.sin_addr.s_addr = INADDR_BROADCAST;
ia->ia_broadaddr.sin_len = sizeof(struct sockaddr_in);
ia->ia_broadaddr.sin_family = AF_INET;
} else {
ia->ia_broadaddr.sin_addr.s_addr =
htonl(ia->ia_subnet | ~ia->ia_subnetmask);
ia->ia_broadaddr.sin_len = sizeof(struct sockaddr_in);
ia->ia_broadaddr.sin_family = AF_INET;
}
}
if (ifp->if_flags & IFF_POINTOPOINT)
ia->ia_dstaddr = *dstaddr;
if (vhid != 0) {
error = (*carp_attach_p)(&ia->ia_ifa, vhid);
if (error)
return (error);
}
/* if_addrhead is already referenced by ifa_alloc() */
IF_ADDR_WLOCK(ifp);
CK_STAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
IF_ADDR_WUNLOCK(ifp);
ifa_ref(ifa); /* in_ifaddrhead */
sx_assert(&in_control_sx, SA_XLOCKED);
CK_STAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
CK_LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia,
ia_hash);
/*
* Give the interface a chance to initialize
* if this is its first address,
* and to validate the address if necessary.
*/
if (ifp->if_ioctl != NULL) {
error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
if (error)
goto fail1;
}
/*
* Add route for the network.
*/
if (vhid == 0) {
error = in_addprefix(ia);
if (error)
goto fail1;
}
/*
* Add a loopback route to self.
*/
if (vhid == 0 && ia_need_loopback_route(ia)) {
struct in_ifaddr *eia;
eia = in_localip_more(ia);
if (eia == NULL) {
error = ifa_add_loopback_route((struct ifaddr *)ia,
(struct sockaddr *)&ia->ia_addr);
if (error)
goto fail2;
} else
ifa_free(&eia->ia_ifa);
}
if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST)) {
struct in_addr allhosts_addr;
struct in_ifinfo *ii;
ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
error = in_joingroup(ifp, &allhosts_addr, NULL,
&ii->ii_allhosts);
}
/*
* Note: we don't need extra reference for ifa, since we called
* with sx lock held, and ifaddr can not be deleted in concurrent
* thread.
*/
EVENTHANDLER_INVOKE(ifaddr_event_ext, ifp, ifa, IFADDR_EVENT_ADD);
return (error);
fail2:
if (vhid == 0)
(void )in_scrubprefix(ia, LLE_STATIC);
fail1:
if (ia->ia_ifa.ifa_carp)
(*carp_detach_p)(&ia->ia_ifa, false);
IF_ADDR_WLOCK(ifp);
CK_STAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifaddr, ifa_link);
IF_ADDR_WUNLOCK(ifp);
ifa_free(&ia->ia_ifa); /* if_addrhead */
sx_assert(&in_control_sx, SA_XLOCKED);
CK_STAILQ_REMOVE(&V_in_ifaddrhead, ia, in_ifaddr, ia_link);
CK_LIST_REMOVE(ia, ia_hash);
ifa_free(&ia->ia_ifa); /* in_ifaddrhead */
return (error);
}
static int
in_difaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct ucred *cred)
{
const struct ifreq *ifr = (struct ifreq *)data;
const struct sockaddr_in *addr = (const struct sockaddr_in *)
&ifr->ifr_addr;
struct ifaddr *ifa;
struct in_ifaddr *ia;
bool deleteAny, iaIsLast;
int error;
if (cred != NULL) {
error = priv_check_cred(cred, PRIV_NET_DELIFADDR);
if (error)
return (error);
}
if (addr->sin_len != sizeof(struct sockaddr_in) ||
addr->sin_family != AF_INET)
deleteAny = true;
else
deleteAny = false;
iaIsLast = true;
ia = NULL;
IF_ADDR_WLOCK(ifp);
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
struct in_ifaddr *it;
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
it = (struct in_ifaddr *)ifa;
if (deleteAny && ia == NULL && (cred == NULL ||
prison_check_ip4(cred, &it->ia_addr.sin_addr) == 0))
ia = it;
if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr &&
(cred == NULL || prison_check_ip4(cred,
&addr->sin_addr) == 0))
ia = it;
if (it != ia)
iaIsLast = false;
}
if (ia == NULL) {
IF_ADDR_WUNLOCK(ifp);
return (EADDRNOTAVAIL);
}
CK_STAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifaddr, ifa_link);
IF_ADDR_WUNLOCK(ifp);
ifa_free(&ia->ia_ifa); /* if_addrhead */
sx_assert(&in_control_sx, SA_XLOCKED);
CK_STAILQ_REMOVE(&V_in_ifaddrhead, ia, in_ifaddr, ia_link);
CK_LIST_REMOVE(ia, ia_hash);
/*
* in_scrubprefix() kills the interface route.
*/
in_scrubprefix(ia, LLE_STATIC);
/*
* in_ifadown gets rid of all the rest of
* the routes. This is not quite the right
* thing to do, but at least if we are running
* a routing process they will come back.
*/
in_ifadown(&ia->ia_ifa, 1);
if (ia->ia_ifa.ifa_carp)
(*carp_detach_p)(&ia->ia_ifa, cmd == SIOCAIFADDR);
/*
* If this is the last IPv4 address configured on this
* interface, leave the all-hosts group.
* No state-change report need be transmitted.
*/
if (iaIsLast && (ifp->if_flags & IFF_MULTICAST)) {
struct in_ifinfo *ii;
ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
if (ii->ii_allhosts) {
(void)in_leavegroup(ii->ii_allhosts, NULL);
ii->ii_allhosts = NULL;
}
}
IF_ADDR_WLOCK(ifp);
if (callout_stop(&ia->ia_garp_timer) == 1) {
ifa_free(&ia->ia_ifa);
}
IF_ADDR_WUNLOCK(ifp);
EVENTHANDLER_INVOKE(ifaddr_event_ext, ifp, &ia->ia_ifa,
IFADDR_EVENT_DEL);
ifa_free(&ia->ia_ifa); /* in_ifaddrhead */
return (0);
}
static int
in_gifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct ucred *cred)
{
struct in_aliasreq *ifra = (struct in_aliasreq *)data;
const struct sockaddr_in *addr = &ifra->ifra_addr;
struct epoch_tracker et;
struct ifaddr *ifa;
struct in_ifaddr *ia;
/*
* ifra_addr must be present and be of INET family.
*/
if (addr->sin_len != sizeof(struct sockaddr_in) ||
addr->sin_family != AF_INET)
return (EINVAL);
/*
* See whether address exist.
*/
ia = NULL;
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
struct in_ifaddr *it;
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
it = (struct in_ifaddr *)ifa;
if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr &&
prison_check_ip4(cred, &addr->sin_addr) == 0) {
ia = it;
break;
}
}
if (ia == NULL) {
NET_EPOCH_EXIT(et);
return (EADDRNOTAVAIL);
}
ifra->ifra_mask = ia->ia_sockmask;
if ((ifp->if_flags & IFF_POINTOPOINT) &&
ia->ia_dstaddr.sin_family == AF_INET)
ifra->ifra_dstaddr = ia->ia_dstaddr;
else if ((ifp->if_flags & IFF_BROADCAST) &&
ia->ia_broadaddr.sin_family == AF_INET)
ifra->ifra_broadaddr = ia->ia_broadaddr;
else
memset(&ifra->ifra_broadaddr, 0,
sizeof(ifra->ifra_broadaddr));
NET_EPOCH_EXIT(et);
return (0);
}
static int
in_match_ifaddr(const struct rtentry *rt, const struct nhop_object *nh, void *arg)
{
if (nh->nh_ifa == (struct ifaddr *)arg)
return (1);
return (0);
}
static int
in_handle_prefix_route(uint32_t fibnum, int cmd,
struct sockaddr_in *dst, struct sockaddr_in *netmask, struct ifaddr *ifa,
struct ifnet *ifp)
{
NET_EPOCH_ASSERT();
/* Prepare gateway */
struct sockaddr_dl_short sdl = {
.sdl_family = AF_LINK,
.sdl_len = sizeof(struct sockaddr_dl_short),
.sdl_type = ifa->ifa_ifp->if_type,
.sdl_index = ifa->ifa_ifp->if_index,
};
struct rt_addrinfo info = {
.rti_ifa = ifa,
.rti_ifp = ifp,
.rti_flags = RTF_PINNED | ((netmask != NULL) ? 0 : RTF_HOST),
.rti_info = {
[RTAX_DST] = (struct sockaddr *)dst,
[RTAX_NETMASK] = (struct sockaddr *)netmask,
[RTAX_GATEWAY] = (struct sockaddr *)&sdl,
},
/* Ensure we delete the prefix IFF prefix ifa matches */
.rti_filter = in_match_ifaddr,
.rti_filterdata = ifa,
};
return (rib_handle_ifaddr_info(fibnum, cmd, &info));
}
/*
* Routing table interaction with interface addresses.
*
* In general, two types of routes needs to be installed:
* a) "interface" or "prefix" route, telling user that the addresses
* behind the ifa prefix are reached directly.
* b) "loopback" route installed for the ifa address, telling user that
* the address belongs to local system.
*
* Handling for (a) and (b) differs in multi-fib aspects, hence they
* are implemented in different functions below.
*
* The cases above may intersect - /32 interface aliases results in
* the same prefix produced by (a) and (b). This blurs the definition
* of the "loopback" route and complicate interactions. The interaction
* table is defined below. The case numbers are used in the multiple
* functions below to refer to the particular test case.
*
* There can be multiple options:
* 1) Adding address with prefix on non-p2p/non-loopback interface.
* Example: 192.0.2.1/24. Action:
* * add "prefix" route towards 192.0.2.0/24 via @ia interface,
* using @ia as an address source.
* * add "loopback" route towards 192.0.2.1 via V_loif, saving
* @ia ifp in the gateway and using @ia as an address source.
*
* 2) Adding address with /32 mask to non-p2p/non-loopback interface.
* Example: 192.0.2.2/32. Action:
* * add "prefix" host route via V_loif, using @ia as an address source.
*
* 3) Adding address with or without prefix to p2p interface.
* Example: 10.0.0.1/24->10.0.0.2. Action:
* * add "prefix" host route towards 10.0.0.2 via this interface, using @ia
* as an address source. Note: no sense in installing full /24 as the interface
* is point-to-point.
* * add "loopback" route towards 10.0.9.1 via V_loif, saving
* @ia ifp in the gateway and using @ia as an address source.
*
* 4) Adding address with or without prefix to loopback interface.
* Example: 192.0.2.1/24. Action:
* * add "prefix" host route via @ia interface, using @ia as an address source.
* Note: Skip installing /24 prefix as it would introduce TTL loop
* for the traffic destined to these addresses.
*/
/*
* Checks if @ia needs to install loopback route to @ia address via
* ifa_maintain_loopback_route().
*
* Return true on success.
*/
static bool
ia_need_loopback_route(const struct in_ifaddr *ia)
{
struct ifnet *ifp = ia->ia_ifp;
/* Case 4: Skip loopback interfaces */
if ((ifp->if_flags & IFF_LOOPBACK) ||
(ia->ia_addr.sin_addr.s_addr == INADDR_ANY))
return (false);
/* Clash avoidance: Skip p2p interfaces with both addresses are equal */
if ((ifp->if_flags & IFF_POINTOPOINT) &&
ia->ia_dstaddr.sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr)
return (false);
/* Case 2: skip /32 prefixes */
if (!(ifp->if_flags & IFF_POINTOPOINT) &&
(ia->ia_sockmask.sin_addr.s_addr == INADDR_BROADCAST))
return (false);
return (true);
}
/*
* Calculate "prefix" route corresponding to @ia.
*/
static void
ia_getrtprefix(const struct in_ifaddr *ia, struct in_addr *prefix, struct in_addr *mask)
{
if (ia->ia_ifp->if_flags & IFF_POINTOPOINT) {
/* Case 3: return host route for dstaddr */
*prefix = ia->ia_dstaddr.sin_addr;
mask->s_addr = INADDR_BROADCAST;
} else if (ia->ia_ifp->if_flags & IFF_LOOPBACK) {
/* Case 4: return host route for ifaddr */
*prefix = ia->ia_addr.sin_addr;
mask->s_addr = INADDR_BROADCAST;
} else {
/* Cases 1,2: return actual ia prefix */
*prefix = ia->ia_addr.sin_addr;
*mask = ia->ia_sockmask.sin_addr;
prefix->s_addr &= mask->s_addr;
}
}
/*
* Adds or delete interface "prefix" route corresponding to @ifa.
* Returns 0 on success or errno.
*/
static int
in_handle_ifaddr_route(int cmd, struct in_ifaddr *ia)
{
struct ifaddr *ifa = &ia->ia_ifa;
struct in_addr daddr, maddr;
struct sockaddr_in *pmask;
struct epoch_tracker et;
int error;
ia_getrtprefix(ia, &daddr, &maddr);
struct sockaddr_in mask = {
.sin_family = AF_INET,
.sin_len = sizeof(struct sockaddr_in),
.sin_addr = maddr,
};
pmask = (maddr.s_addr != INADDR_BROADCAST) ? &mask : NULL;
struct sockaddr_in dst = {
.sin_family = AF_INET,
.sin_len = sizeof(struct sockaddr_in),
.sin_addr.s_addr = daddr.s_addr & maddr.s_addr,
};
struct ifnet *ifp = ia->ia_ifp;
if ((maddr.s_addr == INADDR_BROADCAST) &&
(!(ia->ia_ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)))) {
/* Case 2: host route on broadcast interface */
ifp = V_loif;
}
uint32_t fibnum = ifa->ifa_ifp->if_fib;
NET_EPOCH_ENTER(et);
error = in_handle_prefix_route(fibnum, cmd, &dst, pmask, ifa, ifp);
NET_EPOCH_EXIT(et);
return (error);
}
/*
* Check if we have a route for the given prefix already.
*/
static bool
in_hasrtprefix(struct in_ifaddr *target)
{
struct epoch_tracker et;
struct in_ifaddr *ia;
struct in_addr prefix, mask, p, m;
bool result = false;
ia_getrtprefix(target, &prefix, &mask);
/* Look for an existing address with the same prefix, mask, and fib */
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
ia_getrtprefix(ia, &p, &m);
if (prefix.s_addr != p.s_addr ||
mask.s_addr != m.s_addr)
continue;
if (target->ia_ifp->if_fib != ia->ia_ifp->if_fib)
continue;
/*
* If we got a matching prefix route inserted by other
* interface address, we are done here.
*/
if (ia->ia_flags & IFA_ROUTE) {
result = true;
break;
}
}
NET_EPOCH_EXIT(et);
return (result);
}
int
in_addprefix(struct in_ifaddr *target)
{
int error;
if (in_hasrtprefix(target)) {
if (V_nosameprefix)
return (EEXIST);
else {
rt_addrmsg(RTM_ADD, &target->ia_ifa,
target->ia_ifp->if_fib);
return (0);
}
}
/*
* No-one seem to have this prefix route, so we try to insert it.
*/
rt_addrmsg(RTM_ADD, &target->ia_ifa, target->ia_ifp->if_fib);
error = in_handle_ifaddr_route(RTM_ADD, target);
if (!error)
target->ia_flags |= IFA_ROUTE;
return (error);
}
/*
* Removes either all lle entries for given @ia, or lle
* corresponding to @ia address.
*/
static void
in_scrubprefixlle(struct in_ifaddr *ia, int all, u_int flags)
{
struct sockaddr_in addr, mask;
struct sockaddr *saddr, *smask;
struct ifnet *ifp;
saddr = (struct sockaddr *)&addr;
bzero(&addr, sizeof(addr));
addr.sin_len = sizeof(addr);
addr.sin_family = AF_INET;
smask = (struct sockaddr *)&mask;
bzero(&mask, sizeof(mask));
mask.sin_len = sizeof(mask);
mask.sin_family = AF_INET;
mask.sin_addr.s_addr = ia->ia_subnetmask;
ifp = ia->ia_ifp;
if (all) {
/*
* Remove all L2 entries matching given prefix.
* Convert address to host representation to avoid
* doing this on every callback. ia_subnetmask is already
* stored in host representation.
*/
addr.sin_addr.s_addr = ntohl(ia->ia_addr.sin_addr.s_addr);
lltable_prefix_free(AF_INET, saddr, smask, flags);
} else {
/* Remove interface address only */
addr.sin_addr.s_addr = ia->ia_addr.sin_addr.s_addr;
lltable_delete_addr(LLTABLE(ifp), LLE_IFADDR, saddr);
}
}
/*
* If there is no other address in the system that can serve a route to the
* same prefix, remove the route. Hand over the route to the new address
* otherwise.
*/
int
in_scrubprefix(struct in_ifaddr *target, u_int flags)
{
struct epoch_tracker et;
struct in_ifaddr *ia;
struct in_addr prefix, mask, p, m;
int error = 0;
/*
* Remove the loopback route to the interface address.
*/
if (ia_need_loopback_route(target) && (flags & LLE_STATIC)) {
struct in_ifaddr *eia;
eia = in_localip_more(target);
if (eia != NULL) {
error = ifa_switch_loopback_route((struct ifaddr *)eia,
(struct sockaddr *)&target->ia_addr);
ifa_free(&eia->ia_ifa);
} else {
error = ifa_del_loopback_route((struct ifaddr *)target,
(struct sockaddr *)&target->ia_addr);
}
}
ia_getrtprefix(target, &prefix, &mask);
if ((target->ia_flags & IFA_ROUTE) == 0) {
rt_addrmsg(RTM_DELETE, &target->ia_ifa, target->ia_ifp->if_fib);
/*
* Removing address from !IFF_UP interface or
* prefix which exists on other interface (along with route).
* No entries should exist here except target addr.
* Given that, delete this entry only.
*/
in_scrubprefixlle(target, 0, flags);
return (0);
}
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
ia_getrtprefix(ia, &p, &m);
if (prefix.s_addr != p.s_addr ||
mask.s_addr != m.s_addr)
continue;
if ((ia->ia_ifp->if_flags & IFF_UP) == 0)
continue;
/*
* If we got a matching prefix address, move IFA_ROUTE and
* the route itself to it. Make sure that routing daemons
* get a heads-up.
*/
if ((ia->ia_flags & IFA_ROUTE) == 0) {
ifa_ref(&ia->ia_ifa);
NET_EPOCH_EXIT(et);
error = in_handle_ifaddr_route(RTM_DELETE, target);
if (error == 0)
target->ia_flags &= ~IFA_ROUTE;
else
log(LOG_INFO, "in_scrubprefix: err=%d, old prefix delete failed\n",
error);
/* Scrub all entries IFF interface is different */
in_scrubprefixlle(target, target->ia_ifp != ia->ia_ifp,
flags);
error = in_handle_ifaddr_route(RTM_ADD, ia);
if (error == 0)
ia->ia_flags |= IFA_ROUTE;
else
log(LOG_INFO, "in_scrubprefix: err=%d, new prefix add failed\n",
error);
ifa_free(&ia->ia_ifa);
return (error);
}
}
NET_EPOCH_EXIT(et);
/*
* remove all L2 entries on the given prefix
*/
in_scrubprefixlle(target, 1, flags);
/*
* As no-one seem to have this prefix, we can remove the route.
*/
rt_addrmsg(RTM_DELETE, &target->ia_ifa, target->ia_ifp->if_fib);
error = in_handle_ifaddr_route(RTM_DELETE, target);
if (error == 0)
target->ia_flags &= ~IFA_ROUTE;
else
log(LOG_INFO, "in_scrubprefix: err=%d, prefix delete failed\n", error);
return (error);
}
void
in_ifscrub_all(void)
{
struct ifnet *ifp;
struct ifaddr *ifa, *nifa;
struct ifaliasreq ifr;
IFNET_RLOCK();
CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
/* Cannot lock here - lock recursion. */
/* NET_EPOCH_ENTER(et); */
CK_STAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, nifa) {
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
/*
* This is ugly but the only way for legacy IP to
* cleanly remove addresses and everything attached.
*/
bzero(&ifr, sizeof(ifr));
ifr.ifra_addr = *ifa->ifa_addr;
if (ifa->ifa_dstaddr)
ifr.ifra_broadaddr = *ifa->ifa_dstaddr;
(void)in_control(NULL, SIOCDIFADDR, (caddr_t)&ifr,
ifp, NULL);
}
/* NET_EPOCH_EXIT(et); */
in_purgemaddrs(ifp);
igmp_domifdetach(ifp);
}
IFNET_RUNLOCK();
}
int
in_ifaddr_broadcast(struct in_addr in, struct in_ifaddr *ia)
{
return ((in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
/*
* Optionally check for old-style (host 0) broadcast, but
* taking into account that RFC 3021 obsoletes it.
*/
(V_broadcast_lowest && ia->ia_subnetmask != IN_RFC3021_MASK &&
ntohl(in.s_addr) == ia->ia_subnet)) &&
/*
* Check for an all one subnetmask. These
* only exist when an interface gets a secondary
* address.
*/
ia->ia_subnetmask != (u_long)0xffffffff);
}
/*
* Return 1 if the address might be a local broadcast address.
*/
int
in_broadcast(struct in_addr in, struct ifnet *ifp)
{
struct ifaddr *ifa;
int found;
NET_EPOCH_ASSERT();
if (in.s_addr == INADDR_BROADCAST ||
in.s_addr == INADDR_ANY)
return (1);
if ((ifp->if_flags & IFF_BROADCAST) == 0)
return (0);
found = 0;
/*
* Look through the list of addresses for a match
* with a broadcast address.
*/
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
if (ifa->ifa_addr->sa_family == AF_INET &&
in_ifaddr_broadcast(in, (struct in_ifaddr *)ifa)) {
found = 1;
break;
}
return (found);
}
/*
* On interface removal, clean up IPv4 data structures hung off of the ifnet.
*/
void
in_ifdetach(struct ifnet *ifp)
{
IN_MULTI_LOCK();
in_pcbpurgeif0(&V_ripcbinfo, ifp);
in_pcbpurgeif0(&V_udbinfo, ifp);
in_pcbpurgeif0(&V_ulitecbinfo, ifp);
in_purgemaddrs(ifp);
IN_MULTI_UNLOCK();
/*
* Make sure all multicast deletions invoking if_ioctl() are
* completed before returning. Else we risk accessing a freed
* ifnet structure pointer.
*/
inm_release_wait(NULL);
}
static void
in_ifnet_event(void *arg __unused, struct ifnet *ifp, int event)
{
struct epoch_tracker et;
struct ifaddr *ifa;
struct in_ifaddr *ia;
int error;
NET_EPOCH_ENTER(et);
switch (event) {
case IFNET_EVENT_DOWN:
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
ia = (struct in_ifaddr *)ifa;
if ((ia->ia_flags & IFA_ROUTE) == 0)
continue;
ifa_ref(ifa);
/*
* in_scrubprefix() kills the interface route.
*/
in_scrubprefix(ia, 0);
/*
* in_ifadown gets rid of all the rest of the
* routes. This is not quite the right thing
* to do, but at least if we are running a
* routing process they will come back.
*/
in_ifadown(ifa, 0);
ifa_free(ifa);
}
break;
case IFNET_EVENT_UP:
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
if (ifa->ifa_addr->sa_family != AF_INET)
continue;
ia = (struct in_ifaddr *)ifa;
if (ia->ia_flags & IFA_ROUTE)
continue;
ifa_ref(ifa);
error = ifa_del_loopback_route(ifa, ifa->ifa_addr);
rt_addrmsg(RTM_ADD, ifa, ifa->ifa_ifp->if_fib);
error = in_handle_ifaddr_route(RTM_ADD, ia);
if (error == 0)
ia->ia_flags |= IFA_ROUTE;
error = ifa_add_loopback_route(ifa, ifa->ifa_addr);
ifa_free(ifa);
}
break;
}
NET_EPOCH_EXIT(et);
}
EVENTHANDLER_DEFINE(ifnet_event, in_ifnet_event, NULL, EVENTHANDLER_PRI_ANY);
/*
* Delete all IPv4 multicast address records, and associated link-layer
* multicast address records, associated with ifp.
* XXX It looks like domifdetach runs AFTER the link layer cleanup.
* XXX This should not race with ifma_protospec being set during
* a new allocation, if it does, we have bigger problems.
*/
static void
in_purgemaddrs(struct ifnet *ifp)
{
struct epoch_tracker et;
struct in_multi_head purgeinms;
struct in_multi *inm;
struct ifmultiaddr *ifma;
SLIST_INIT(&purgeinms);
IN_MULTI_LIST_LOCK();
/*
* Extract list of in_multi associated with the detaching ifp
* which the PF_INET layer is about to release.
* We need to do this as IF_ADDR_LOCK() may be re-acquired
* by code further down.
*/
IF_ADDR_WLOCK(ifp);
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = inm_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
inm_rele_locked(&purgeinms, inm);
}
NET_EPOCH_EXIT(et);
IF_ADDR_WUNLOCK(ifp);
inm_release_list_deferred(&purgeinms);
igmp_ifdetach(ifp);
IN_MULTI_LIST_UNLOCK();
}
struct in_llentry {
struct llentry base;
};
#define IN_LLTBL_DEFAULT_HSIZE 32
#define IN_LLTBL_HASH(k, h) \
(((((((k >> 8) ^ k) >> 8) ^ k) >> 8) ^ k) & ((h) - 1))
/*
* Do actual deallocation of @lle.
*/
static void
in_lltable_destroy_lle_unlocked(epoch_context_t ctx)
{
struct llentry *lle;
lle = __containerof(ctx, struct llentry, lle_epoch_ctx);
LLE_LOCK_DESTROY(lle);
LLE_REQ_DESTROY(lle);
free(lle, M_LLTABLE);
}
/*
* Called by LLE_FREE_LOCKED when number of references
* drops to zero.
*/
static void
in_lltable_destroy_lle(struct llentry *lle)
{
LLE_WUNLOCK(lle);
NET_EPOCH_CALL(in_lltable_destroy_lle_unlocked, &lle->lle_epoch_ctx);
}
static struct llentry *
in_lltable_new(struct in_addr addr4, u_int flags)
{
struct in_llentry *lle;
lle = malloc(sizeof(struct in_llentry), M_LLTABLE, M_NOWAIT | M_ZERO);
if (lle == NULL) /* NB: caller generates msg */
return NULL;
/*
* For IPv4 this will trigger "arpresolve" to generate
* an ARP request.
*/
lle->base.la_expire = time_uptime; /* mark expired */
lle->base.r_l3addr.addr4 = addr4;
lle->base.lle_refcnt = 1;
lle->base.lle_free = in_lltable_destroy_lle;
LLE_LOCK_INIT(&lle->base);
LLE_REQ_INIT(&lle->base);
callout_init(&lle->base.lle_timer, 1);
return (&lle->base);
}
#define IN_ARE_MASKED_ADDR_EQUAL(d, a, m) ( \
((((d).s_addr ^ (a).s_addr) & (m).s_addr)) == 0 )
static int
in_lltable_match_prefix(const struct sockaddr *saddr,
const struct sockaddr *smask, u_int flags, struct llentry *lle)
{
struct in_addr addr, mask, lle_addr;
addr = ((const struct sockaddr_in *)saddr)->sin_addr;
mask = ((const struct sockaddr_in *)smask)->sin_addr;
lle_addr.s_addr = ntohl(lle->r_l3addr.addr4.s_addr);
if (IN_ARE_MASKED_ADDR_EQUAL(lle_addr, addr, mask) == 0)
return (0);
if (lle->la_flags & LLE_IFADDR) {
/*
* Delete LLE_IFADDR records IFF address & flag matches.
* Note that addr is the interface address within prefix
* being matched.
* Note also we should handle 'ifdown' cases without removing
* ifaddr macs.
*/
if (addr.s_addr == lle_addr.s_addr && (flags & LLE_STATIC) != 0)
return (1);
return (0);
}
/* flags & LLE_STATIC means deleting both dynamic and static entries */
if ((flags & LLE_STATIC) || !(lle->la_flags & LLE_STATIC))
return (1);
return (0);
}
static void
in_lltable_free_entry(struct lltable *llt, struct llentry *lle)
{
size_t pkts_dropped;
LLE_WLOCK_ASSERT(lle);
KASSERT(llt != NULL, ("lltable is NULL"));
/* Unlink entry from table if not already */
if ((lle->la_flags & LLE_LINKED) != 0) {
IF_AFDATA_WLOCK_ASSERT(llt->llt_ifp);
lltable_unlink_entry(llt, lle);
}
/* Drop hold queue */
pkts_dropped = llentry_free(lle);
ARPSTAT_ADD(dropped, pkts_dropped);
}
static int
in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
{
struct nhop_object *nh;
struct in_addr addr;
KASSERT(l3addr->sa_family == AF_INET,
("sin_family %d", l3addr->sa_family));
addr = ((const struct sockaddr_in *)l3addr)->sin_addr;
nh = fib4_lookup(ifp->if_fib, addr, 0, NHR_NONE, 0);
if (nh == NULL)
return (EINVAL);
/*
* If the gateway for an existing host route matches the target L3
* address, which is a special route inserted by some implementation
* such as MANET, and the interface is of the correct type, then
* allow for ARP to proceed.
*/
if (nh->nh_flags & NHF_GATEWAY) {
if (!(nh->nh_flags & NHF_HOST) || nh->nh_ifp->if_type != IFT_ETHER ||
(nh->nh_ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) != 0 ||
memcmp(nh->gw_sa.sa_data, l3addr->sa_data,
sizeof(in_addr_t)) != 0) {
return (EINVAL);
}
}
/*
* Make sure that at least the destination address is covered
* by the route. This is for handling the case where 2 or more
* interfaces have the same prefix. An incoming packet arrives
* on one interface and the corresponding outgoing packet leaves
* another interface.
*/
if ((nh->nh_ifp != ifp) && (nh->nh_flags & NHF_HOST) == 0) {
struct in_ifaddr *ia = (struct in_ifaddr *)ifaof_ifpforaddr(l3addr, ifp);
struct in_addr dst_addr, mask_addr;
if (ia == NULL)
return (EINVAL);
/*
* ifaof_ifpforaddr() returns _best matching_ IFA.
* It is possible that ifa prefix does not cover our address.
* Explicitly verify and fail if that's the case.
*/
dst_addr = IA_SIN(ia)->sin_addr;
mask_addr.s_addr = htonl(ia->ia_subnetmask);
if (!IN_ARE_MASKED_ADDR_EQUAL(dst_addr, addr, mask_addr))
return (EINVAL);
}
return (0);
}
static inline uint32_t
in_lltable_hash_dst(const struct in_addr dst, uint32_t hsize)
{
return (IN_LLTBL_HASH(dst.s_addr, hsize));
}
static uint32_t
in_lltable_hash(const struct llentry *lle, uint32_t hsize)
{
return (in_lltable_hash_dst(lle->r_l3addr.addr4, hsize));
}
static void
in_lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa)
{
struct sockaddr_in *sin;
sin = (struct sockaddr_in *)sa;
bzero(sin, sizeof(*sin));
sin->sin_family = AF_INET;
sin->sin_len = sizeof(*sin);
sin->sin_addr = lle->r_l3addr.addr4;
}
static inline struct llentry *
in_lltable_find_dst(struct lltable *llt, struct in_addr dst)
{
struct llentry *lle;
struct llentries *lleh;
u_int hashidx;
hashidx = in_lltable_hash_dst(dst, llt->llt_hsize);
lleh = &llt->lle_head[hashidx];
CK_LIST_FOREACH(lle, lleh, lle_next) {
if (lle->la_flags & LLE_DELETED)
continue;
if (lle->r_l3addr.addr4.s_addr == dst.s_addr)
break;
}
return (lle);
}
static void
in_lltable_delete_entry(struct lltable *llt, struct llentry *lle)
{
lle->la_flags |= LLE_DELETED;
EVENTHANDLER_INVOKE(lle_event, lle, LLENTRY_DELETED);
#ifdef DIAGNOSTIC
log(LOG_INFO, "ifaddr cache = %p is deleted\n", lle);
#endif
llentry_free(lle);
}
static struct llentry *
in_lltable_alloc(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
{
const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
struct ifnet *ifp = llt->llt_ifp;
struct llentry *lle;
char linkhdr[LLE_MAX_LINKHDR];
size_t linkhdrsize;
int lladdr_off;
KASSERT(l3addr->sa_family == AF_INET,
("sin_family %d", l3addr->sa_family));
/*
* A route that covers the given address must have
* been installed 1st because we are doing a resolution,
* verify this.
*/
if (!(flags & LLE_IFADDR) &&
in_lltable_rtcheck(ifp, flags, l3addr) != 0)
return (NULL);
lle = in_lltable_new(sin->sin_addr, flags);
if (lle == NULL) {
log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
return (NULL);
}
lle->la_flags = flags;
if (flags & LLE_STATIC)
lle->r_flags |= RLLE_VALID;
if ((flags & LLE_IFADDR) == LLE_IFADDR) {
linkhdrsize = LLE_MAX_LINKHDR;
if (lltable_calc_llheader(ifp, AF_INET, IF_LLADDR(ifp),
linkhdr, &linkhdrsize, &lladdr_off) != 0) {
in_lltable_free_entry(llt, lle);
return (NULL);
}
lltable_set_entry_addr(ifp, lle, linkhdr, linkhdrsize,
lladdr_off);
lle->la_flags |= LLE_STATIC;
lle->r_flags |= (RLLE_VALID | RLLE_IFADDR);
lle->la_expire = 0;
}
return (lle);
}
/*
* Return NULL if not found or marked for deletion.
* If found return lle read locked.
*/
static struct llentry *
in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
{
const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
struct llentry *lle;
IF_AFDATA_LOCK_ASSERT(llt->llt_ifp);
KASSERT(l3addr->sa_family == AF_INET,
("sin_family %d", l3addr->sa_family));
KASSERT((flags & (LLE_UNLOCKED | LLE_EXCLUSIVE)) !=
(LLE_UNLOCKED | LLE_EXCLUSIVE),
("wrong lle request flags: %#x", flags));
lle = in_lltable_find_dst(llt, sin->sin_addr);
if (lle == NULL)
return (NULL);
if (flags & LLE_UNLOCKED)
return (lle);
if (flags & LLE_EXCLUSIVE)
LLE_WLOCK(lle);
else
LLE_RLOCK(lle);
/*
* If the afdata lock is not held, the LLE may have been unlinked while
* we were blocked on the LLE lock. Check for this case.
*/
if (__predict_false((lle->la_flags & LLE_LINKED) == 0)) {
if (flags & LLE_EXCLUSIVE)
LLE_WUNLOCK(lle);
else
LLE_RUNLOCK(lle);
return (NULL);
}
return (lle);
}
static int
in_lltable_dump_entry(struct lltable *llt, struct llentry *lle,
struct sysctl_req *wr)
{
struct ifnet *ifp = llt->llt_ifp;
/* XXX stack use */
struct {
struct rt_msghdr rtm;
struct sockaddr_in sin;
struct sockaddr_dl sdl;
} arpc;
struct sockaddr_dl *sdl;
int error;
bzero(&arpc, sizeof(arpc));
/* skip deleted entries */
if ((lle->la_flags & LLE_DELETED) == LLE_DELETED)
return (0);
/* Skip if jailed and not a valid IP of the prison. */
lltable_fill_sa_entry(lle,(struct sockaddr *)&arpc.sin);
if (prison_if(wr->td->td_ucred, (struct sockaddr *)&arpc.sin) != 0)
return (0);
/*
* produce a msg made of:
* struct rt_msghdr;
* struct sockaddr_in; (IPv4)
* struct sockaddr_dl;
*/
arpc.rtm.rtm_msglen = sizeof(arpc);
arpc.rtm.rtm_version = RTM_VERSION;
arpc.rtm.rtm_type = RTM_GET;
arpc.rtm.rtm_flags = RTF_UP;
arpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY;
/* publish */
if (lle->la_flags & LLE_PUB)
arpc.rtm.rtm_flags |= RTF_ANNOUNCE;
sdl = &arpc.sdl;
sdl->sdl_family = AF_LINK;
sdl->sdl_len = sizeof(*sdl);
sdl->sdl_index = ifp->if_index;
sdl->sdl_type = ifp->if_type;
if ((lle->la_flags & LLE_VALID) == LLE_VALID) {
sdl->sdl_alen = ifp->if_addrlen;
bcopy(lle->ll_addr, LLADDR(sdl), ifp->if_addrlen);
} else {
sdl->sdl_alen = 0;
bzero(LLADDR(sdl), ifp->if_addrlen);
}
arpc.rtm.rtm_rmx.rmx_expire =
lle->la_flags & LLE_STATIC ? 0 : lle->la_expire;
arpc.rtm.rtm_flags |= (RTF_HOST | RTF_LLDATA);
if (lle->la_flags & LLE_STATIC)
arpc.rtm.rtm_flags |= RTF_STATIC;
if (lle->la_flags & LLE_IFADDR)
arpc.rtm.rtm_flags |= RTF_PINNED;
arpc.rtm.rtm_index = ifp->if_index;
error = SYSCTL_OUT(wr, &arpc, sizeof(arpc));
return (error);
}
static void
in_lltable_post_resolved(struct lltable *llt, struct llentry *lle)
{
struct ifnet *ifp = llt->llt_ifp;
/* gratuitous ARP */
if ((lle->la_flags & LLE_PUB) != 0)
arprequest(ifp, &lle->r_l3addr.addr4, &lle->r_l3addr.addr4,
lle->ll_addr);
}
static struct lltable *
in_lltattach(struct ifnet *ifp)
{
struct lltable *llt;
llt = lltable_allocate_htbl(IN_LLTBL_DEFAULT_HSIZE);
llt->llt_af = AF_INET;
llt->llt_ifp = ifp;
llt->llt_lookup = in_lltable_lookup;
llt->llt_alloc_entry = in_lltable_alloc;
llt->llt_delete_entry = in_lltable_delete_entry;
llt->llt_dump_entry = in_lltable_dump_entry;
llt->llt_hash = in_lltable_hash;
llt->llt_fill_sa_entry = in_lltable_fill_sa_entry;
llt->llt_free_entry = in_lltable_free_entry;
llt->llt_match_prefix = in_lltable_match_prefix;
llt->llt_mark_used = llentry_mark_used;
llt->llt_post_resolved = in_lltable_post_resolved;
lltable_link(llt);
return (llt);
}
struct lltable *
in_lltable_get(struct ifnet *ifp)
{
struct lltable *llt = NULL;
void *afdata_ptr = ifp->if_afdata[AF_INET];
if (afdata_ptr != NULL)
llt = ((struct in_ifinfo *)afdata_ptr)->ii_llt;
return (llt);
}
void *
in_domifattach(struct ifnet *ifp)
{
struct in_ifinfo *ii;
ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
ii->ii_llt = in_lltattach(ifp);
ii->ii_igmp = igmp_domifattach(ifp);
return (ii);
}
void
in_domifdetach(struct ifnet *ifp, void *aux)
{
struct in_ifinfo *ii = (struct in_ifinfo *)aux;
igmp_domifdetach(ifp);
lltable_free(ii->ii_llt);
free(ii, M_IFADDR);
}