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freebsd-dev/sys/netinet/in.c
Gleb Smirnoff 28ebe80cab Provide functions to determine presence of a given address 
configured on a given interface.

Discussed with:	np
Sponsored by:	Nginx, Inc.
2015-04-17 11:57:06 +00:00

1293 lines
32 KiB
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/*-
* 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.
* 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.
*
* 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_mpath.h"
#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/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_types.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/if_ether.h>
#include <netinet/in.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 thread *);
static int in_difaddr_ioctl(caddr_t, struct ifnet *, struct thread *);
static void in_socktrim(struct sockaddr_in *);
static void in_purgemaddrs(struct ifnet *);
static VNET_DEFINE(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_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)
{
register u_long i = ntohl(in.s_addr);
register struct in_ifaddr *ia;
IN_IFADDR_RLOCK();
TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
if ((i & ia->ia_subnetmask) == ia->ia_subnet) {
IN_IFADDR_RUNLOCK();
return (1);
}
}
IN_IFADDR_RUNLOCK();
return (0);
}
/*
* Return 1 if an internet address is for the local host and configured
* on one of its interfaces.
*/
int
in_localip(struct in_addr in)
{
struct in_ifaddr *ia;
IN_IFADDR_RLOCK();
LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr) {
IN_IFADDR_RUNLOCK();
return (1);
}
}
IN_IFADDR_RUNLOCK();
return (0);
}
/*
* 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;
IF_ADDR_RLOCK(ifp);
TAILQ_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) {
IF_ADDR_RUNLOCK(ifp);
return (1);
}
}
IF_ADDR_RUNLOCK(ifp);
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 *ia)
{
in_addr_t in = IA_SIN(ia)->sin_addr.s_addr;
struct in_ifaddr *it;
IN_IFADDR_RLOCK();
LIST_FOREACH(it, INADDR_HASH(in), ia_hash) {
if (it != ia && IA_SIN(it)->sin_addr.s_addr == in) {
ifa_ref(&it->ia_ifa);
IN_IFADDR_RUNLOCK();
return (it);
}
}
IN_IFADDR_RUNLOCK();
return (NULL);
}
/*
* 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)
{
register u_long i = ntohl(in.s_addr);
register u_long net;
if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
return (0);
if (IN_CLASSA(i)) {
net = i & IN_CLASSA_NET;
if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
return (0);
}
return (1);
}
/*
* Trim a mask in a sockaddr
*/
static void
in_socktrim(struct sockaddr_in *ap)
{
register char *cplim = (char *) &ap->sin_addr;
register 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, caddr_t data, struct ifnet *ifp,
struct thread *td)
{
struct ifreq *ifr = (struct ifreq *)data;
struct sockaddr_in *addr = (struct sockaddr_in *)&ifr->ifr_addr;
struct ifaddr *ifa;
struct in_ifaddr *ia;
int error;
if (ifp == NULL)
return (EADDRNOTAVAIL);
/*
* 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 SIOCDIFADDR:
sx_xlock(&in_control_sx);
error = in_difaddr_ioctl(data, ifp, td);
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, td);
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(td->td_ucred, &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.
*/
IF_ADDR_RLOCK(ifp);
TAILQ_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)
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
if (ifa->ifa_addr->sa_family == AF_INET) {
ia = (struct in_ifaddr *)ifa;
if (prison_check_ip4(td->td_ucred,
&ia->ia_addr.sin_addr) == 0)
break;
}
if (ifa == NULL) {
IF_ADDR_RUNLOCK(ifp);
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;
}
IF_ADDR_RUNLOCK(ifp);
return (error);
}
static int
in_aifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td)
{
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 ifaddr *ifa;
struct in_ifaddr *ia;
bool iaIsFirst;
int error = 0;
error = priv_check(td, 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;
IF_ADDR_RLOCK(ifp);
TAILQ_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;
iaIsFirst = false;
if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr &&
prison_check_ip4(td->td_ucred, &addr->sin_addr) == 0)
ia = it;
}
IF_ADDR_RUNLOCK(ifp);
if (ia != NULL)
(void )in_difaddr_ioctl(data, ifp, td);
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;
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);
/*
* Be compatible with network classes, if netmask isn't
* supplied, guess it based on classes.
*/
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;
/* XXXGL: rtinit() needs this strange assignment. */
if (ifp->if_flags & IFF_LOOPBACK)
ia->ia_dstaddr = ia->ia_addr;
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);
TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
IF_ADDR_WUNLOCK(ifp);
ifa_ref(ifa); /* in_ifaddrhead */
IN_IFADDR_WLOCK();
TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
IN_IFADDR_WUNLOCK();
/*
* 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) {
int flags = RTF_UP;
if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
flags |= RTF_HOST;
error = in_addprefix(ia, flags);
if (error)
goto fail1;
}
/*
* Add a loopback route to self.
*/
if (vhid == 0 && (ifp->if_flags & IFF_LOOPBACK) == 0 &&
ia->ia_addr.sin_addr.s_addr != INADDR_ANY &&
!((ifp->if_flags & IFF_POINTOPOINT) &&
ia->ia_dstaddr.sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr)) {
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);
}
EVENTHANDLER_INVOKE(ifaddr_event, ifp);
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);
IF_ADDR_WLOCK(ifp);
TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
IF_ADDR_WUNLOCK(ifp);
ifa_free(&ia->ia_ifa); /* if_addrhead */
IN_IFADDR_WLOCK();
TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
LIST_REMOVE(ia, ia_hash);
IN_IFADDR_WUNLOCK();
ifa_free(&ia->ia_ifa); /* in_ifaddrhead */
return (error);
}
static int
in_difaddr_ioctl(caddr_t data, struct ifnet *ifp, struct thread *td)
{
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 (td != NULL) {
error = priv_check(td, 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);
TAILQ_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 && (td == NULL ||
prison_check_ip4(td->td_ucred, &it->ia_addr.sin_addr) == 0))
ia = it;
if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr &&
(td == NULL || prison_check_ip4(td->td_ucred,
&addr->sin_addr) == 0))
ia = it;
if (it != ia)
iaIsLast = false;
}
if (ia == NULL) {
IF_ADDR_WUNLOCK(ifp);
return (EADDRNOTAVAIL);
}
TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
IF_ADDR_WUNLOCK(ifp);
ifa_free(&ia->ia_ifa); /* if_addrhead */
IN_IFADDR_WLOCK();
TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
LIST_REMOVE(ia, ia_hash);
IN_IFADDR_WUNLOCK();
/*
* 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);
/*
* 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]);
IN_MULTI_LOCK();
if (ii->ii_allhosts) {
(void)in_leavegroup_locked(ii->ii_allhosts, NULL);
ii->ii_allhosts = NULL;
}
IN_MULTI_UNLOCK();
}
EVENTHANDLER_INVOKE(ifaddr_event, ifp);
ifa_free(&ia->ia_ifa); /* in_ifaddrhead */
return (0);
}
#define rtinitflags(x) \
((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
? RTF_HOST : 0)
/*
* Check if we have a route for the given prefix already or add one accordingly.
*/
int
in_addprefix(struct in_ifaddr *target, int flags)
{
struct in_ifaddr *ia;
struct in_addr prefix, mask, p, m;
int error;
if ((flags & RTF_HOST) != 0) {
prefix = target->ia_dstaddr.sin_addr;
mask.s_addr = 0;
} else {
prefix = target->ia_addr.sin_addr;
mask = target->ia_sockmask.sin_addr;
prefix.s_addr &= mask.s_addr;
}
IN_IFADDR_RLOCK();
/* Look for an existing address with the same prefix, mask, and fib */
TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
if (rtinitflags(ia)) {
p = ia->ia_dstaddr.sin_addr;
if (prefix.s_addr != p.s_addr)
continue;
} else {
p = ia->ia_addr.sin_addr;
m = ia->ia_sockmask.sin_addr;
p.s_addr &= m.s_addr;
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) {
#ifdef RADIX_MPATH
if (ia->ia_addr.sin_addr.s_addr ==
target->ia_addr.sin_addr.s_addr) {
IN_IFADDR_RUNLOCK();
return (EEXIST);
} else
break;
#endif
if (V_nosameprefix) {
IN_IFADDR_RUNLOCK();
return (EEXIST);
} else {
int fibnum;
fibnum = V_rt_add_addr_allfibs ? RT_ALL_FIBS :
target->ia_ifp->if_fib;
rt_addrmsg(RTM_ADD, &target->ia_ifa, fibnum);
IN_IFADDR_RUNLOCK();
return (0);
}
}
}
IN_IFADDR_RUNLOCK();
/*
* No-one seem to have this prefix route, so we try to insert it.
*/
error = rtinit(&target->ia_ifa, (int)RTM_ADD, flags);
if (!error)
target->ia_flags |= IFA_ROUTE;
return (error);
}
/*
* 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 in_ifaddr *ia;
struct in_addr prefix, mask, p, m;
int error = 0;
struct sockaddr_in prefix0, mask0;
/*
* Remove the loopback route to the interface address.
*/
if ((target->ia_addr.sin_addr.s_addr != INADDR_ANY) &&
!(target->ia_ifp->if_flags & IFF_LOOPBACK) &&
(flags & LLE_STATIC)) {
struct in_ifaddr *eia;
eia = in_localip_more(target);
if (eia != NULL) {
int fibnum = target->ia_ifp->if_fib;
error = ifa_switch_loopback_route((struct ifaddr *)eia,
(struct sockaddr *)&target->ia_addr, fibnum);
ifa_free(&eia->ia_ifa);
} else {
error = ifa_del_loopback_route((struct ifaddr *)target,
(struct sockaddr *)&target->ia_addr);
}
if (!(target->ia_ifp->if_flags & IFF_NOARP))
/* remove arp cache */
arp_ifscrub(target->ia_ifp,
IA_SIN(target)->sin_addr.s_addr);
}
if (rtinitflags(target)) {
prefix = target->ia_dstaddr.sin_addr;
mask.s_addr = 0;
} else {
prefix = target->ia_addr.sin_addr;
mask = target->ia_sockmask.sin_addr;
prefix.s_addr &= mask.s_addr;
}
if ((target->ia_flags & IFA_ROUTE) == 0) {
int fibnum;
fibnum = V_rt_add_addr_allfibs ? RT_ALL_FIBS :
target->ia_ifp->if_fib;
rt_addrmsg(RTM_DELETE, &target->ia_ifa, fibnum);
return (0);
}
IN_IFADDR_RLOCK();
TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
if (rtinitflags(ia)) {
p = ia->ia_dstaddr.sin_addr;
if (prefix.s_addr != p.s_addr)
continue;
} else {
p = ia->ia_addr.sin_addr;
m = ia->ia_sockmask.sin_addr;
p.s_addr &= m.s_addr;
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);
IN_IFADDR_RUNLOCK();
error = rtinit(&(target->ia_ifa), (int)RTM_DELETE,
rtinitflags(target));
if (error == 0)
target->ia_flags &= ~IFA_ROUTE;
else
log(LOG_INFO, "in_scrubprefix: err=%d, old prefix delete failed\n",
error);
error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
rtinitflags(ia) | RTF_UP);
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);
}
}
IN_IFADDR_RUNLOCK();
/*
* remove all L2 entries on the given prefix
*/
bzero(&prefix0, sizeof(prefix0));
prefix0.sin_len = sizeof(prefix0);
prefix0.sin_family = AF_INET;
prefix0.sin_addr.s_addr = target->ia_subnet;
bzero(&mask0, sizeof(mask0));
mask0.sin_len = sizeof(mask0);
mask0.sin_family = AF_INET;
mask0.sin_addr.s_addr = target->ia_subnetmask;
lltable_prefix_free(AF_INET, (struct sockaddr *)&prefix0,
(struct sockaddr *)&mask0, flags);
/*
* As no-one seem to have this prefix, we can remove the route.
*/
error = rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
if (error == 0)
target->ia_flags &= ~IFA_ROUTE;
else
log(LOG_INFO, "in_scrubprefix: err=%d, prefix delete failed\n", error);
return (error);
}
#undef rtinitflags
/*
* Return 1 if the address might be a local broadcast address.
*/
int
in_broadcast(struct in_addr in, struct ifnet *ifp)
{
register struct ifaddr *ifa;
u_long t;
if (in.s_addr == INADDR_BROADCAST ||
in.s_addr == INADDR_ANY)
return (1);
if ((ifp->if_flags & IFF_BROADCAST) == 0)
return (0);
t = ntohl(in.s_addr);
/*
* Look through the list of addresses for a match
* with a broadcast address.
*/
#define ia ((struct in_ifaddr *)ifa)
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
if (ifa->ifa_addr->sa_family == AF_INET &&
(in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
/*
* Check for old-style (host 0) broadcast, but
* taking into account that RFC 3021 obsoletes it.
*/
(ia->ia_subnetmask != IN_RFC3021_MASK &&
t == 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);
return (0);
#undef ia
}
/*
* On interface removal, clean up IPv4 data structures hung off of the ifnet.
*/
void
in_ifdetach(struct ifnet *ifp)
{
in_pcbpurgeif0(&V_ripcbinfo, ifp);
in_pcbpurgeif0(&V_udbinfo, ifp);
in_pcbpurgeif0(&V_ulitecbinfo, ifp);
in_purgemaddrs(ifp);
}
/*
* 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)
{
LIST_HEAD(,in_multi) purgeinms;
struct in_multi *inm, *tinm;
struct ifmultiaddr *ifma;
LIST_INIT(&purgeinms);
IN_MULTI_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_RLOCK(ifp);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_INET ||
ifma->ifma_protospec == NULL)
continue;
#if 0
KASSERT(ifma->ifma_protospec != NULL,
("%s: ifma_protospec is NULL", __func__));
#endif
inm = (struct in_multi *)ifma->ifma_protospec;
LIST_INSERT_HEAD(&purgeinms, inm, inm_link);
}
IF_ADDR_RUNLOCK(ifp);
LIST_FOREACH_SAFE(inm, &purgeinms, inm_link, tinm) {
LIST_REMOVE(inm, inm_link);
inm_release_locked(inm);
}
igmp_ifdetach(ifp);
IN_MULTI_UNLOCK();
}
struct in_llentry {
struct llentry base;
struct sockaddr_in l3_addr4;
};
/*
* Deletes an address from the address table.
* This function is called by the timer functions
* such as arptimer() and nd6_llinfo_timer(), and
* the caller does the locking.
*/
static void
in_lltable_free(struct lltable *llt, struct llentry *lle)
{
LLE_WUNLOCK(lle);
LLE_LOCK_DESTROY(lle);
free(lle, M_LLTABLE);
}
static struct llentry *
in_lltable_new(const struct sockaddr *l3addr, 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->l3_addr4 = *(const struct sockaddr_in *)l3addr;
lle->base.lle_refcnt = 1;
lle->base.lle_free = in_lltable_free;
LLE_LOCK_INIT(&lle->base);
callout_init(&lle->base.la_timer, 1);
return (&lle->base);
}
#define IN_ARE_MASKED_ADDR_EQUAL(d, a, m) ( \
(((ntohl((d)->sin_addr.s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 )
static void
in_lltable_prefix_free(struct lltable *llt, const struct sockaddr *prefix,
const struct sockaddr *mask, u_int flags)
{
const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
struct llentry *lle, *next;
int i;
size_t pkts_dropped;
IF_AFDATA_WLOCK(llt->llt_ifp);
for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) {
/*
* (flags & LLE_STATIC) means deleting all entries
* including static ARP entries.
*/
if (IN_ARE_MASKED_ADDR_EQUAL(satosin(L3_ADDR(lle)),
pfx, msk) && ((flags & LLE_STATIC) ||
!(lle->la_flags & LLE_STATIC))) {
LLE_WLOCK(lle);
if (callout_stop(&lle->la_timer))
LLE_REMREF(lle);
pkts_dropped = llentry_free(lle);
ARPSTAT_ADD(dropped, pkts_dropped);
}
}
}
IF_AFDATA_WUNLOCK(llt->llt_ifp);
}
static int
in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
{
struct rtentry *rt;
KASSERT(l3addr->sa_family == AF_INET,
("sin_family %d", l3addr->sa_family));
/* XXX rtalloc1_fib should take a const param */
rt = rtalloc1_fib(__DECONST(struct sockaddr *, l3addr), 0, 0,
ifp->if_fib);
if (rt == 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 (rt->rt_flags & RTF_GATEWAY) {
if (!(rt->rt_flags & RTF_HOST) || !rt->rt_ifp ||
rt->rt_ifp->if_type != IFT_ETHER ||
(rt->rt_ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) != 0 ||
memcmp(rt->rt_gateway->sa_data, l3addr->sa_data,
sizeof(in_addr_t)) != 0) {
RTFREE_LOCKED(rt);
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 (!(rt->rt_flags & RTF_HOST) && rt->rt_ifp != ifp) {
const char *sa, *mask, *addr, *lim;
int len;
mask = (const char *)rt_mask(rt);
/*
* Just being extra cautious to avoid some custom
* code getting into trouble.
*/
if (mask == NULL) {
RTFREE_LOCKED(rt);
return (EINVAL);
}
sa = (const char *)rt_key(rt);
addr = (const char *)l3addr;
len = ((const struct sockaddr_in *)l3addr)->sin_len;
lim = addr + len;
for ( ; addr < lim; sa++, mask++, addr++) {
if ((*sa ^ *addr) & *mask) {
#ifdef DIAGNOSTIC
log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
#endif
RTFREE_LOCKED(rt);
return (EINVAL);
}
}
}
RTFREE_LOCKED(rt);
return (0);
}
/*
* 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 ifnet *ifp = llt->llt_ifp;
struct llentry *lle;
struct llentries *lleh;
u_int hashkey;
IF_AFDATA_LOCK_ASSERT(ifp);
KASSERT(l3addr->sa_family == AF_INET,
("sin_family %d", l3addr->sa_family));
hashkey = sin->sin_addr.s_addr;
lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
LIST_FOREACH(lle, lleh, lle_next) {
struct sockaddr_in *sa2 = satosin(L3_ADDR(lle));
if (lle->la_flags & LLE_DELETED)
continue;
if (sa2->sin_addr.s_addr == sin->sin_addr.s_addr)
break;
}
if (lle == NULL) {
#ifdef DIAGNOSTIC
if (flags & LLE_DELETE)
log(LOG_INFO, "interface address is missing from cache = %p in delete\n", lle);
#endif
if (!(flags & LLE_CREATE))
return (NULL);
IF_AFDATA_WLOCK_ASSERT(ifp);
/*
* 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)
goto done;
lle = in_lltable_new(l3addr, flags);
if (lle == NULL) {
log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
goto done;
}
lle->la_flags = flags & ~LLE_CREATE;
if ((flags & (LLE_CREATE | LLE_IFADDR)) == (LLE_CREATE | LLE_IFADDR)) {
bcopy(IF_LLADDR(ifp), &lle->ll_addr, ifp->if_addrlen);
lle->la_flags |= (LLE_VALID | LLE_STATIC);
}
lle->lle_tbl = llt;
lle->lle_head = lleh;
lle->la_flags |= LLE_LINKED;
LIST_INSERT_HEAD(lleh, lle, lle_next);
} else if (flags & LLE_DELETE) {
if (!(lle->la_flags & LLE_IFADDR) || (flags & LLE_IFADDR)) {
LLE_WLOCK(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
if ((lle->la_flags &
(LLE_STATIC | LLE_IFADDR)) == LLE_STATIC)
llentry_free(lle);
else
LLE_WUNLOCK(lle);
}
lle = (void *)-1;
}
if (LLE_IS_VALID(lle)) {
if (flags & LLE_EXCLUSIVE)
LLE_WLOCK(lle);
else
LLE_RLOCK(lle);
}
done:
return (lle);
}
static int
in_lltable_dump(struct lltable *llt, struct sysctl_req *wr)
{
#define SIN(lle) ((struct sockaddr_in *) L3_ADDR(lle))
struct ifnet *ifp = llt->llt_ifp;
struct llentry *lle;
/* XXX stack use */
struct {
struct rt_msghdr rtm;
struct sockaddr_in sin;
struct sockaddr_dl sdl;
} arpc;
int error, i;
LLTABLE_LOCK_ASSERT();
error = 0;
for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
LIST_FOREACH(lle, &llt->lle_head[i], lle_next) {
struct sockaddr_dl *sdl;
/* skip deleted entries */
if ((lle->la_flags & LLE_DELETED) == LLE_DELETED)
continue;
/* Skip if jailed and not a valid IP of the prison. */
if (prison_if(wr->td->td_ucred, L3_ADDR(lle)) != 0)
continue;
/*
* produce a msg made of:
* struct rt_msghdr;
* struct sockaddr_in; (IPv4)
* struct sockaddr_dl;
*/
bzero(&arpc, sizeof(arpc));
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;
arpc.sin.sin_family = AF_INET;
arpc.sin.sin_len = sizeof(arpc.sin);
arpc.sin.sin_addr.s_addr = SIN(lle)->sin_addr.s_addr;
/* 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;
arpc.rtm.rtm_index = ifp->if_index;
error = SYSCTL_OUT(wr, &arpc, sizeof(arpc));
if (error)
break;
}
}
return error;
#undef SIN
}
void *
in_domifattach(struct ifnet *ifp)
{
struct in_ifinfo *ii;
struct lltable *llt;
ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
llt = lltable_init(ifp, AF_INET);
if (llt != NULL) {
llt->llt_prefix_free = in_lltable_prefix_free;
llt->llt_lookup = in_lltable_lookup;
llt->llt_dump = in_lltable_dump;
}
ii->ii_llt = llt;
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);
}
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