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mirror of https://git.FreeBSD.org/src.git synced 2024-12-24 11:29:10 +00:00
freebsd/sys/netinet/in.c
2007-05-10 15:58:48 +00:00

1162 lines
29 KiB
C

/*-
* 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
* $FreeBSD$
*/
#include "opt_carp.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sockio.h>
#include <sys/malloc.h>
#include <sys/priv.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_pcb.h>
#include <netinet/igmp_var.h>
static MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
static int in_mask2len(struct in_addr *);
static void in_len2mask(struct in_addr *, int);
static int in_lifaddr_ioctl(struct socket *, u_long, caddr_t,
struct ifnet *, struct thread *);
static int in_addprefix(struct in_ifaddr *, int);
static int in_scrubprefix(struct in_ifaddr *);
static void in_socktrim(struct sockaddr_in *);
static int in_ifinit(struct ifnet *,
struct in_ifaddr *, struct sockaddr_in *, int);
static void in_purgemaddrs(struct ifnet *);
static int subnetsarelocal = 0;
SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
&subnetsarelocal, 0, "Treat all subnets as directly connected");
static int sameprefixcarponly = 0;
SYSCTL_INT(_net_inet_ip, OID_AUTO, same_prefix_carp_only, CTLFLAG_RW,
&sameprefixcarponly, 0,
"Refuse to create same prefixes on different interfaces");
/*
* The IPv4 multicast list (in_multihead and associated structures) are
* protected by the global in_multi_mtx. See in_var.h for more details. For
* now, in_multi_mtx is marked as recursible due to IGMP's calling back into
* ip_output() to send IGMP packets while holding the lock; this probably is
* not quite desirable.
*/
struct in_multihead in_multihead; /* XXX BSS initialization */
struct mtx in_multi_mtx;
MTX_SYSINIT(in_multi_mtx, &in_multi_mtx, "in_multi_mtx", MTX_DEF | MTX_RECURSE);
extern struct inpcbinfo ripcbinfo;
extern struct inpcbinfo udbinfo;
/*
* Return 1 if an internet address is for a ``local'' host
* (one to which we have a connection). If subnetsarelocal
* is true, this includes other subnets of the local net.
* Otherwise, it includes only the directly-connected (sub)nets.
*/
int
in_localaddr(struct in_addr in)
{
register u_long i = ntohl(in.s_addr);
register struct in_ifaddr *ia;
if (subnetsarelocal) {
TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link)
if ((i & ia->ia_netmask) == ia->ia_net)
return (1);
} else {
TAILQ_FOREACH(ia, &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.
*/
int
in_localip(struct in_addr in)
{
struct in_ifaddr *ia;
LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr)
return 1;
}
return 0;
}
/*
* 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;
}
}
static int
in_mask2len(mask)
struct in_addr *mask;
{
int x, y;
u_char *p;
p = (u_char *)mask;
for (x = 0; x < sizeof(*mask); x++) {
if (p[x] != 0xff)
break;
}
y = 0;
if (x < sizeof(*mask)) {
for (y = 0; y < 8; y++) {
if ((p[x] & (0x80 >> y)) == 0)
break;
}
}
return x * 8 + y;
}
static void
in_len2mask(struct in_addr *mask, int len)
{
int i;
u_char *p;
p = (u_char *)mask;
bzero(mask, sizeof(*mask));
for (i = 0; i < len / 8; i++)
p[i] = 0xff;
if (len % 8)
p[i] = (0xff00 >> (len % 8)) & 0xff;
}
/*
* Generic internet control operations (ioctl's).
* Ifp is 0 if not an interface-specific ioctl.
*/
/* ARGSUSED */
int
in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
struct thread *td)
{
register struct ifreq *ifr = (struct ifreq *)data;
register struct in_ifaddr *ia = 0, *iap;
register struct ifaddr *ifa;
struct in_addr allhosts_addr;
struct in_addr dst;
struct in_ifaddr *oia;
struct in_aliasreq *ifra = (struct in_aliasreq *)data;
struct sockaddr_in oldaddr;
int error, hostIsNew, iaIsNew, maskIsNew, s;
int iaIsFirst;
iaIsFirst = 0;
iaIsNew = 0;
allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
switch (cmd) {
case SIOCALIFADDR:
if (td != NULL) {
error = priv_check(td, PRIV_NET_ADDIFADDR);
if (error)
return (error);
}
if (!ifp)
return EINVAL;
return in_lifaddr_ioctl(so, cmd, data, ifp, td);
case SIOCDLIFADDR:
if (td != NULL) {
error = priv_check(td, PRIV_NET_DELIFADDR);
if (error)
return (error);
}
if (!ifp)
return EINVAL;
return in_lifaddr_ioctl(so, cmd, data, ifp, td);
case SIOCGLIFADDR:
if (!ifp)
return EINVAL;
return in_lifaddr_ioctl(so, cmd, data, ifp, td);
}
/*
* Find address for this interface, if it exists.
*
* If an alias address was specified, find that one instead of
* the first one on the interface, if possible.
*/
if (ifp) {
dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash)
if (iap->ia_ifp == ifp &&
iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
ia = iap;
break;
}
if (ia == NULL)
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
iap = ifatoia(ifa);
if (iap->ia_addr.sin_family == AF_INET) {
ia = iap;
break;
}
}
if (ia == NULL)
iaIsFirst = 1;
}
switch (cmd) {
case SIOCAIFADDR:
case SIOCDIFADDR:
if (ifp == 0)
return (EADDRNOTAVAIL);
if (ifra->ifra_addr.sin_family == AF_INET) {
for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
if (ia->ia_ifp == ifp &&
ia->ia_addr.sin_addr.s_addr ==
ifra->ifra_addr.sin_addr.s_addr)
break;
}
if ((ifp->if_flags & IFF_POINTOPOINT)
&& (cmd == SIOCAIFADDR)
&& (ifra->ifra_dstaddr.sin_addr.s_addr
== INADDR_ANY)) {
return EDESTADDRREQ;
}
}
if (cmd == SIOCDIFADDR && ia == 0)
return (EADDRNOTAVAIL);
/* FALLTHROUGH */
case SIOCSIFADDR:
case SIOCSIFNETMASK:
case SIOCSIFDSTADDR:
if (td != NULL) {
error = priv_check(td, PRIV_NET_ADDIFADDR);
if (error)
return (error);
}
if (ifp == 0)
return (EADDRNOTAVAIL);
if (ia == (struct in_ifaddr *)0) {
ia = (struct in_ifaddr *)
malloc(sizeof *ia, M_IFADDR, M_WAITOK | M_ZERO);
if (ia == (struct in_ifaddr *)NULL)
return (ENOBUFS);
/*
* Protect from ipintr() traversing address list
* while we're modifying it.
*/
s = splnet();
ifa = &ia->ia_ifa;
IFA_LOCK_INIT(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;
ifa->ifa_refcnt = 1;
TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
ia->ia_sockmask.sin_len = 8;
ia->ia_sockmask.sin_family = AF_INET;
if (ifp->if_flags & IFF_BROADCAST) {
ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
ia->ia_broadaddr.sin_family = AF_INET;
}
ia->ia_ifp = ifp;
TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_link);
splx(s);
iaIsNew = 1;
}
break;
case SIOCSIFBRDADDR:
if (td != NULL) {
error = priv_check(td, PRIV_NET_ADDIFADDR);
if (error)
return (error);
}
/* FALLTHROUGH */
case SIOCGIFADDR:
case SIOCGIFNETMASK:
case SIOCGIFDSTADDR:
case SIOCGIFBRDADDR:
if (ia == (struct in_ifaddr *)0)
return (EADDRNOTAVAIL);
break;
}
switch (cmd) {
case SIOCGIFADDR:
*((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
return (0);
case SIOCGIFBRDADDR:
if ((ifp->if_flags & IFF_BROADCAST) == 0)
return (EINVAL);
*((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
return (0);
case SIOCGIFDSTADDR:
if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
return (EINVAL);
*((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
return (0);
case SIOCGIFNETMASK:
*((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
return (0);
case SIOCSIFDSTADDR:
if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
return (EINVAL);
oldaddr = ia->ia_dstaddr;
ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
if (ifp->if_ioctl) {
IFF_LOCKGIANT(ifp);
error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR,
(caddr_t)ia);
IFF_UNLOCKGIANT(ifp);
if (error) {
ia->ia_dstaddr = oldaddr;
return (error);
}
}
if (ia->ia_flags & IFA_ROUTE) {
ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
ia->ia_ifa.ifa_dstaddr =
(struct sockaddr *)&ia->ia_dstaddr;
rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
}
return (0);
case SIOCSIFBRDADDR:
if ((ifp->if_flags & IFF_BROADCAST) == 0)
return (EINVAL);
ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
return (0);
case SIOCSIFADDR:
error = in_ifinit(ifp, ia,
(struct sockaddr_in *) &ifr->ifr_addr, 1);
if (error != 0 && iaIsNew)
break;
if (error == 0) {
if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST) != 0)
in_addmulti(&allhosts_addr, ifp);
EVENTHANDLER_INVOKE(ifaddr_event, ifp);
}
return (0);
case SIOCSIFNETMASK:
ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
return (0);
case SIOCAIFADDR:
maskIsNew = 0;
hostIsNew = 1;
error = 0;
if (ia->ia_addr.sin_family == AF_INET) {
if (ifra->ifra_addr.sin_len == 0) {
ifra->ifra_addr = ia->ia_addr;
hostIsNew = 0;
} else if (ifra->ifra_addr.sin_addr.s_addr ==
ia->ia_addr.sin_addr.s_addr)
hostIsNew = 0;
}
if (ifra->ifra_mask.sin_len) {
in_ifscrub(ifp, ia);
ia->ia_sockmask = ifra->ifra_mask;
ia->ia_sockmask.sin_family = AF_INET;
ia->ia_subnetmask =
ntohl(ia->ia_sockmask.sin_addr.s_addr);
maskIsNew = 1;
}
if ((ifp->if_flags & IFF_POINTOPOINT) &&
(ifra->ifra_dstaddr.sin_family == AF_INET)) {
in_ifscrub(ifp, ia);
ia->ia_dstaddr = ifra->ifra_dstaddr;
maskIsNew = 1; /* We lie; but the effect's the same */
}
if (ifra->ifra_addr.sin_family == AF_INET &&
(hostIsNew || maskIsNew))
error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
if (error != 0 && iaIsNew)
break;
if ((ifp->if_flags & IFF_BROADCAST) &&
(ifra->ifra_broadaddr.sin_family == AF_INET))
ia->ia_broadaddr = ifra->ifra_broadaddr;
if (error == 0) {
if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST) != 0)
in_addmulti(&allhosts_addr, ifp);
EVENTHANDLER_INVOKE(ifaddr_event, ifp);
}
return (error);
case SIOCDIFADDR:
/*
* in_ifscrub kills the interface route.
*/
in_ifscrub(ifp, ia);
/*
* 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);
EVENTHANDLER_INVOKE(ifaddr_event, ifp);
error = 0;
break;
default:
if (ifp == 0 || ifp->if_ioctl == 0)
return (EOPNOTSUPP);
IFF_LOCKGIANT(ifp);
error = (*ifp->if_ioctl)(ifp, cmd, data);
IFF_UNLOCKGIANT(ifp);
return (error);
}
/*
* Protect from ipintr() traversing address list while we're modifying
* it.
*/
s = splnet();
TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
TAILQ_REMOVE(&in_ifaddrhead, ia, ia_link);
if (ia->ia_addr.sin_family == AF_INET) {
LIST_REMOVE(ia, ia_hash);
/*
* If this is the last IPv4 address configured on this
* interface, leave the all-hosts group.
* XXX: This is quite ugly because of locking and structure.
*/
oia = NULL;
IFP_TO_IA(ifp, oia);
if (oia == NULL) {
struct in_multi *inm;
IFF_LOCKGIANT(ifp);
IN_MULTI_LOCK();
IN_LOOKUP_MULTI(allhosts_addr, ifp, inm);
if (inm != NULL)
in_delmulti_locked(inm);
IN_MULTI_UNLOCK();
IFF_UNLOCKGIANT(ifp);
}
}
IFAFREE(&ia->ia_ifa);
splx(s);
return (error);
}
/*
* SIOC[GAD]LIFADDR.
* SIOCGLIFADDR: get first address. (?!?)
* SIOCGLIFADDR with IFLR_PREFIX:
* get first address that matches the specified prefix.
* SIOCALIFADDR: add the specified address.
* SIOCALIFADDR with IFLR_PREFIX:
* EINVAL since we can't deduce hostid part of the address.
* SIOCDLIFADDR: delete the specified address.
* SIOCDLIFADDR with IFLR_PREFIX:
* delete the first address that matches the specified prefix.
* return values:
* EINVAL on invalid parameters
* EADDRNOTAVAIL on prefix match failed/specified address not found
* other values may be returned from in_ioctl()
*/
static int
in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data,
struct ifnet *ifp, struct thread *td)
{
struct if_laddrreq *iflr = (struct if_laddrreq *)data;
struct ifaddr *ifa;
/* sanity checks */
if (!data || !ifp) {
panic("invalid argument to in_lifaddr_ioctl");
/*NOTRECHED*/
}
switch (cmd) {
case SIOCGLIFADDR:
/* address must be specified on GET with IFLR_PREFIX */
if ((iflr->flags & IFLR_PREFIX) == 0)
break;
/*FALLTHROUGH*/
case SIOCALIFADDR:
case SIOCDLIFADDR:
/* address must be specified on ADD and DELETE */
if (iflr->addr.ss_family != AF_INET)
return EINVAL;
if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
return EINVAL;
/* XXX need improvement */
if (iflr->dstaddr.ss_family
&& iflr->dstaddr.ss_family != AF_INET)
return EINVAL;
if (iflr->dstaddr.ss_family
&& iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
return EINVAL;
break;
default: /*shouldn't happen*/
return EOPNOTSUPP;
}
if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
return EINVAL;
switch (cmd) {
case SIOCALIFADDR:
{
struct in_aliasreq ifra;
if (iflr->flags & IFLR_PREFIX)
return EINVAL;
/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
bzero(&ifra, sizeof(ifra));
bcopy(iflr->iflr_name, ifra.ifra_name,
sizeof(ifra.ifra_name));
bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
if (iflr->dstaddr.ss_family) { /*XXX*/
bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
iflr->dstaddr.ss_len);
}
ifra.ifra_mask.sin_family = AF_INET;
ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td);
}
case SIOCGLIFADDR:
case SIOCDLIFADDR:
{
struct in_ifaddr *ia;
struct in_addr mask, candidate, match;
struct sockaddr_in *sin;
int cmp;
bzero(&mask, sizeof(mask));
if (iflr->flags & IFLR_PREFIX) {
/* lookup a prefix rather than address. */
in_len2mask(&mask, iflr->prefixlen);
sin = (struct sockaddr_in *)&iflr->addr;
match.s_addr = sin->sin_addr.s_addr;
match.s_addr &= mask.s_addr;
/* if you set extra bits, that's wrong */
if (match.s_addr != sin->sin_addr.s_addr)
return EINVAL;
cmp = 1;
} else {
if (cmd == SIOCGLIFADDR) {
/* on getting an address, take the 1st match */
cmp = 0; /*XXX*/
} else {
/* on deleting an address, do exact match */
in_len2mask(&mask, 32);
sin = (struct sockaddr_in *)&iflr->addr;
match.s_addr = sin->sin_addr.s_addr;
cmp = 1;
}
}
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
if (!cmp)
break;
candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
candidate.s_addr &= mask.s_addr;
if (candidate.s_addr == match.s_addr)
break;
}
if (!ifa)
return EADDRNOTAVAIL;
ia = (struct in_ifaddr *)ifa;
if (cmd == SIOCGLIFADDR) {
/* fill in the if_laddrreq structure */
bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
ia->ia_dstaddr.sin_len);
} else
bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
iflr->prefixlen =
in_mask2len(&ia->ia_sockmask.sin_addr);
iflr->flags = 0; /*XXX*/
return 0;
} else {
struct in_aliasreq ifra;
/* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
bzero(&ifra, sizeof(ifra));
bcopy(iflr->iflr_name, ifra.ifra_name,
sizeof(ifra.ifra_name));
bcopy(&ia->ia_addr, &ifra.ifra_addr,
ia->ia_addr.sin_len);
if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
ia->ia_dstaddr.sin_len);
}
bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
ia->ia_sockmask.sin_len);
return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
ifp, td);
}
}
}
return EOPNOTSUPP; /*just for safety*/
}
/*
* Delete any existing route for an interface.
*/
void
in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
{
in_scrubprefix(ia);
}
/*
* Initialize an interface's internet address
* and routing table entry.
*/
static int
in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
int scrub)
{
register u_long i = ntohl(sin->sin_addr.s_addr);
struct sockaddr_in oldaddr;
int s = splimp(), flags = RTF_UP, error = 0;
oldaddr = ia->ia_addr;
if (oldaddr.sin_family == AF_INET)
LIST_REMOVE(ia, ia_hash);
ia->ia_addr = *sin;
if (ia->ia_addr.sin_family == AF_INET)
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) {
IFF_LOCKGIANT(ifp);
error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
IFF_UNLOCKGIANT(ifp);
if (error) {
splx(s);
/* LIST_REMOVE(ia, ia_hash) is done in in_control */
ia->ia_addr = oldaddr;
if (ia->ia_addr.sin_family == AF_INET)
LIST_INSERT_HEAD(INADDR_HASH(
ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
return (error);
}
}
splx(s);
if (scrub) {
ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
in_ifscrub(ifp, ia);
ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
}
if (IN_CLASSA(i))
ia->ia_netmask = IN_CLASSA_NET;
else if (IN_CLASSB(i))
ia->ia_netmask = IN_CLASSB_NET;
else
ia->ia_netmask = IN_CLASSC_NET;
/*
* The subnet mask usually includes at least the standard network part,
* but may may be smaller in the case of supernetting.
* If it is set, we believe it.
*/
if (ia->ia_subnetmask == 0) {
ia->ia_subnetmask = ia->ia_netmask;
ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
} else
ia->ia_netmask &= ia->ia_subnetmask;
ia->ia_net = i & ia->ia_netmask;
ia->ia_subnet = i & ia->ia_subnetmask;
in_socktrim(&ia->ia_sockmask);
#ifdef DEV_CARP
/*
* XXX: carp(4) does not have interface route
*/
if (ifp->if_type == IFT_CARP)
return (0);
#endif
/*
* Add route for the network.
*/
ia->ia_ifa.ifa_metric = ifp->if_metric;
if (ifp->if_flags & IFF_BROADCAST) {
ia->ia_broadaddr.sin_addr.s_addr =
htonl(ia->ia_subnet | ~ia->ia_subnetmask);
ia->ia_netbroadcast.s_addr =
htonl(ia->ia_net | ~ ia->ia_netmask);
} else if (ifp->if_flags & IFF_LOOPBACK) {
ia->ia_dstaddr = ia->ia_addr;
flags |= RTF_HOST;
} else if (ifp->if_flags & IFF_POINTOPOINT) {
if (ia->ia_dstaddr.sin_family != AF_INET)
return (0);
flags |= RTF_HOST;
}
if ((error = in_addprefix(ia, flags)) != 0)
return (error);
return (error);
}
#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 a one
* accordingly.
*/
static 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;
else {
prefix = target->ia_addr.sin_addr;
mask = target->ia_sockmask.sin_addr;
prefix.s_addr &= mask.s_addr;
}
TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
if (rtinitflags(ia)) {
p = ia->ia_addr.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 we got a matching prefix route inserted by other
* interface address, we are done here.
*/
if (ia->ia_flags & IFA_ROUTE) {
if (sameprefixcarponly &&
target->ia_ifp->if_type != IFT_CARP &&
ia->ia_ifp->if_type != IFT_CARP)
return (EEXIST);
else
return (0);
}
}
/*
* 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.
*/
static int
in_scrubprefix(struct in_ifaddr *target)
{
struct in_ifaddr *ia;
struct in_addr prefix, mask, p;
int error;
if ((target->ia_flags & IFA_ROUTE) == 0)
return 0;
if (rtinitflags(target))
prefix = target->ia_dstaddr.sin_addr;
else {
prefix = target->ia_addr.sin_addr;
mask = target->ia_sockmask.sin_addr;
prefix.s_addr &= mask.s_addr;
}
TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
if (rtinitflags(ia))
p = ia->ia_dstaddr.sin_addr;
else {
p = ia->ia_addr.sin_addr;
p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
}
if (prefix.s_addr != p.s_addr)
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.
*
* XXX: a special case for carp(4) interface
*/
if ((ia->ia_flags & IFA_ROUTE) == 0
#ifdef DEV_CARP
&& (ia->ia_ifp->if_type != IFT_CARP)
#endif
) {
rtinit(&(target->ia_ifa), (int)RTM_DELETE,
rtinitflags(target));
target->ia_flags &= ~IFA_ROUTE;
error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
rtinitflags(ia) | RTF_UP);
if (error == 0)
ia->ia_flags |= IFA_ROUTE;
return error;
}
}
/*
* As no-one seem to have this prefix, we can remove the route.
*/
rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
target->ia_flags &= ~IFA_ROUTE;
return 0;
}
#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 ||
in.s_addr == ia->ia_netbroadcast.s_addr ||
/*
* Check for old-style (host 0) broadcast.
*/
t == ia->ia_subnet || t == ia->ia_net) &&
/*
* 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
}
/*
* Add an address to the list of IP multicast addresses for a given interface.
*/
struct in_multi *
in_addmulti(struct in_addr *ap, struct ifnet *ifp)
{
struct in_multi *inm;
inm = NULL;
IFF_LOCKGIANT(ifp);
IN_MULTI_LOCK();
IN_LOOKUP_MULTI(*ap, ifp, inm);
if (inm != NULL) {
/*
* If we already joined this group, just bump the
* refcount and return it.
*/
KASSERT(inm->inm_refcount >= 1,
("%s: bad refcount %d", __func__, inm->inm_refcount));
++inm->inm_refcount;
} else do {
struct sockaddr_in sin;
struct ifmultiaddr *ifma;
struct in_multi *ninm;
int error;
bzero(&sin, sizeof sin);
sin.sin_family = AF_INET;
sin.sin_len = sizeof(struct sockaddr_in);
sin.sin_addr = *ap;
/*
* Check if a link-layer group is already associated
* with this network-layer group on the given ifnet.
* If so, bump the refcount on the existing network-layer
* group association and return it.
*/
error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
if (error)
break;
if (ifma->ifma_protospec != NULL) {
inm = (struct in_multi *)ifma->ifma_protospec;
#ifdef INVARIANTS
if (inm->inm_ifma != ifma || inm->inm_ifp != ifp ||
inm->inm_addr.s_addr != ap->s_addr)
panic("%s: ifma is inconsistent", __func__);
#endif
++inm->inm_refcount;
break;
}
/*
* A new membership is needed; construct it and
* perform the IGMP join.
*/
ninm = malloc(sizeof(*ninm), M_IPMADDR, M_NOWAIT | M_ZERO);
if (ninm == NULL) {
if_delmulti_ifma(ifma);
break;
}
ninm->inm_addr = *ap;
ninm->inm_ifp = ifp;
ninm->inm_ifma = ifma;
ninm->inm_refcount = 1;
ifma->ifma_protospec = ninm;
LIST_INSERT_HEAD(&in_multihead, ninm, inm_link);
igmp_joingroup(ninm);
inm = ninm;
} while (0);
IN_MULTI_UNLOCK();
IFF_UNLOCKGIANT(ifp);
return (inm);
}
/*
* Delete a multicast address record.
* It is OK to call this routine if the underlying ifnet went away.
*
* XXX: To deal with the ifp going away, we cheat; the link-layer code in net
* will set ifma_ifp to NULL when the associated ifnet instance is detached
* from the system.
* The only reason we need to violate layers and check ifma_ifp here at all
* is because certain hardware drivers still require Giant to be held,
* and it must always be taken before other locks.
*/
void
in_delmulti(struct in_multi *inm)
{
struct ifnet *ifp;
KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__));
ifp = inm->inm_ifma->ifma_ifp;
if (ifp != NULL) {
/*
* Sanity check that netinet's notion of ifp is the
* same as net's.
*/
KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__));
IFF_LOCKGIANT(ifp);
}
IN_MULTI_LOCK();
in_delmulti_locked(inm);
IN_MULTI_UNLOCK();
if (ifp != NULL)
IFF_UNLOCKGIANT(ifp);
}
/*
* Delete a multicast address record, with locks held.
*
* It is OK to call this routine if the ifp went away.
* Assumes that caller holds the IN_MULTI lock, and that
* Giant was taken before other locks if required by the hardware.
*/
void
in_delmulti_locked(struct in_multi *inm)
{
struct ifmultiaddr *ifma;
IN_MULTI_LOCK_ASSERT();
KASSERT(inm->inm_refcount >= 1, ("%s: freeing freed inm", __func__));
if (--inm->inm_refcount == 0) {
igmp_leavegroup(inm);
ifma = inm->inm_ifma;
#ifdef DIAGNOSTIC
printf("%s: purging ifma %p\n", __func__, ifma);
#endif
KASSERT(ifma->ifma_protospec == inm,
("%s: ifma_protospec != inm", __func__));
ifma->ifma_protospec = NULL;
LIST_REMOVE(inm, inm_link);
free(inm, M_IPMADDR);
if_delmulti_ifma(ifma);
}
}
/*
* Delete all IPv4 multicast address records, and associated link-layer
* multicast address records, associated with ifp.
*/
static void
in_purgemaddrs(struct ifnet *ifp)
{
struct in_multi *inm;
struct in_multi *oinm;
#ifdef DIAGNOSTIC
printf("%s: purging ifp %p\n", __func__, ifp);
#endif
IFF_LOCKGIANT(ifp);
IN_MULTI_LOCK();
LIST_FOREACH_SAFE(inm, &in_multihead, inm_link, oinm) {
if (inm->inm_ifp == ifp)
in_delmulti_locked(inm);
}
IN_MULTI_UNLOCK();
IFF_UNLOCKGIANT(ifp);
}
/*
* On interface removal, clean up IPv4 data structures hung off of the ifnet.
*/
void
in_ifdetach(struct ifnet *ifp)
{
in_pcbpurgeif0(&ripcbinfo, ifp);
in_pcbpurgeif0(&udbinfo, ifp);
in_purgemaddrs(ifp);
}