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linux/net/ipv4/devinet.c

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/*
* NET3 IP device support routines.
*
* Version: $Id: devinet.c,v 1.44 2001/10/31 21:55:54 davem Exp $
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Derived from the IP parts of dev.c 1.0.19
* Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Mark Evans, <evansmp@uhura.aston.ac.uk>
*
* Additional Authors:
* Alan Cox, <gw4pts@gw4pts.ampr.org>
* Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* Changes:
* Alexey Kuznetsov: pa_* fields are replaced with ifaddr
* lists.
* Cyrus Durgin: updated for kmod
* Matthias Andree: in devinet_ioctl, compare label and
* address (4.4BSD alias style support),
* fall back to comparing just the label
* if no match found.
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/if_ether.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <linux/notifier.h>
#include <linux/inetdevice.h>
#include <linux/igmp.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#include <linux/kmod.h>
#include <net/arp.h>
#include <net/ip.h>
#include <net/route.h>
#include <net/ip_fib.h>
struct ipv4_devconf ipv4_devconf = {
.accept_redirects = 1,
.send_redirects = 1,
.secure_redirects = 1,
.shared_media = 1,
};
static struct ipv4_devconf ipv4_devconf_dflt = {
.accept_redirects = 1,
.send_redirects = 1,
.secure_redirects = 1,
.shared_media = 1,
.accept_source_route = 1,
};
static void rtmsg_ifa(int event, struct in_ifaddr *);
static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
int destroy);
#ifdef CONFIG_SYSCTL
static void devinet_sysctl_register(struct in_device *in_dev,
struct ipv4_devconf *p);
static void devinet_sysctl_unregister(struct ipv4_devconf *p);
#endif
/* Locks all the inet devices. */
static struct in_ifaddr *inet_alloc_ifa(void)
{
struct in_ifaddr *ifa = kmalloc(sizeof(*ifa), GFP_KERNEL);
if (ifa) {
memset(ifa, 0, sizeof(*ifa));
INIT_RCU_HEAD(&ifa->rcu_head);
}
return ifa;
}
static void inet_rcu_free_ifa(struct rcu_head *head)
{
struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
if (ifa->ifa_dev)
in_dev_put(ifa->ifa_dev);
kfree(ifa);
}
static inline void inet_free_ifa(struct in_ifaddr *ifa)
{
call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
}
void in_dev_finish_destroy(struct in_device *idev)
{
struct net_device *dev = idev->dev;
BUG_TRAP(!idev->ifa_list);
BUG_TRAP(!idev->mc_list);
#ifdef NET_REFCNT_DEBUG
printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n",
idev, dev ? dev->name : "NIL");
#endif
dev_put(dev);
if (!idev->dead)
printk("Freeing alive in_device %p\n", idev);
else {
kfree(idev);
}
}
struct in_device *inetdev_init(struct net_device *dev)
{
struct in_device *in_dev;
ASSERT_RTNL();
in_dev = kmalloc(sizeof(*in_dev), GFP_KERNEL);
if (!in_dev)
goto out;
memset(in_dev, 0, sizeof(*in_dev));
INIT_RCU_HEAD(&in_dev->rcu_head);
memcpy(&in_dev->cnf, &ipv4_devconf_dflt, sizeof(in_dev->cnf));
in_dev->cnf.sysctl = NULL;
in_dev->dev = dev;
if ((in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl)) == NULL)
goto out_kfree;
/* Reference in_dev->dev */
dev_hold(dev);
#ifdef CONFIG_SYSCTL
neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
NET_IPV4_NEIGH, "ipv4", NULL, NULL);
#endif
/* Account for reference dev->ip_ptr */
in_dev_hold(in_dev);
rcu_assign_pointer(dev->ip_ptr, in_dev);
#ifdef CONFIG_SYSCTL
devinet_sysctl_register(in_dev, &in_dev->cnf);
#endif
ip_mc_init_dev(in_dev);
if (dev->flags & IFF_UP)
ip_mc_up(in_dev);
out:
return in_dev;
out_kfree:
kfree(in_dev);
in_dev = NULL;
goto out;
}
static void in_dev_rcu_put(struct rcu_head *head)
{
struct in_device *idev = container_of(head, struct in_device, rcu_head);
in_dev_put(idev);
}
static void inetdev_destroy(struct in_device *in_dev)
{
struct in_ifaddr *ifa;
struct net_device *dev;
ASSERT_RTNL();
dev = in_dev->dev;
if (dev == &loopback_dev)
return;
in_dev->dead = 1;
ip_mc_destroy_dev(in_dev);
while ((ifa = in_dev->ifa_list) != NULL) {
inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
inet_free_ifa(ifa);
}
#ifdef CONFIG_SYSCTL
devinet_sysctl_unregister(&in_dev->cnf);
#endif
dev->ip_ptr = NULL;
#ifdef CONFIG_SYSCTL
neigh_sysctl_unregister(in_dev->arp_parms);
#endif
neigh_parms_release(&arp_tbl, in_dev->arp_parms);
arp_ifdown(dev);
call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
}
int inet_addr_onlink(struct in_device *in_dev, u32 a, u32 b)
{
rcu_read_lock();
for_primary_ifa(in_dev) {
if (inet_ifa_match(a, ifa)) {
if (!b || inet_ifa_match(b, ifa)) {
rcu_read_unlock();
return 1;
}
}
} endfor_ifa(in_dev);
rcu_read_unlock();
return 0;
}
static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
int destroy)
{
struct in_ifaddr *promote = NULL;
struct in_ifaddr *ifa, *ifa1 = *ifap;
struct in_ifaddr *last_prim = in_dev->ifa_list;
struct in_ifaddr *prev_prom = NULL;
int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
ASSERT_RTNL();
/* 1. Deleting primary ifaddr forces deletion all secondaries
* unless alias promotion is set
**/
if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
struct in_ifaddr **ifap1 = &ifa1->ifa_next;
while ((ifa = *ifap1) != NULL) {
if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
ifa1->ifa_scope <= ifa->ifa_scope)
last_prim = ifa;
if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
ifa1->ifa_mask != ifa->ifa_mask ||
!inet_ifa_match(ifa1->ifa_address, ifa)) {
ifap1 = &ifa->ifa_next;
prev_prom = ifa;
continue;
}
if (!do_promote) {
*ifap1 = ifa->ifa_next;
rtmsg_ifa(RTM_DELADDR, ifa);
blocking_notifier_call_chain(&inetaddr_chain,
NETDEV_DOWN, ifa);
inet_free_ifa(ifa);
} else {
promote = ifa;
break;
}
}
}
/* 2. Unlink it */
*ifap = ifa1->ifa_next;
/* 3. Announce address deletion */
/* Send message first, then call notifier.
At first sight, FIB update triggered by notifier
will refer to already deleted ifaddr, that could confuse
netlink listeners. It is not true: look, gated sees
that route deleted and if it still thinks that ifaddr
is valid, it will try to restore deleted routes... Grr.
So that, this order is correct.
*/
rtmsg_ifa(RTM_DELADDR, ifa1);
blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
if (promote) {
if (prev_prom) {
prev_prom->ifa_next = promote->ifa_next;
promote->ifa_next = last_prim->ifa_next;
last_prim->ifa_next = promote;
}
promote->ifa_flags &= ~IFA_F_SECONDARY;
rtmsg_ifa(RTM_NEWADDR, promote);
blocking_notifier_call_chain(&inetaddr_chain,
NETDEV_UP, promote);
for (ifa = promote->ifa_next; ifa; ifa = ifa->ifa_next) {
if (ifa1->ifa_mask != ifa->ifa_mask ||
!inet_ifa_match(ifa1->ifa_address, ifa))
continue;
fib_add_ifaddr(ifa);
}
}
if (destroy) {
inet_free_ifa(ifa1);
if (!in_dev->ifa_list)
inetdev_destroy(in_dev);
}
}
static int inet_insert_ifa(struct in_ifaddr *ifa)
{
struct in_device *in_dev = ifa->ifa_dev;
struct in_ifaddr *ifa1, **ifap, **last_primary;
ASSERT_RTNL();
if (!ifa->ifa_local) {
inet_free_ifa(ifa);
return 0;
}
ifa->ifa_flags &= ~IFA_F_SECONDARY;
last_primary = &in_dev->ifa_list;
for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
ifap = &ifa1->ifa_next) {
if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
ifa->ifa_scope <= ifa1->ifa_scope)
last_primary = &ifa1->ifa_next;
if (ifa1->ifa_mask == ifa->ifa_mask &&
inet_ifa_match(ifa1->ifa_address, ifa)) {
if (ifa1->ifa_local == ifa->ifa_local) {
inet_free_ifa(ifa);
return -EEXIST;
}
if (ifa1->ifa_scope != ifa->ifa_scope) {
inet_free_ifa(ifa);
return -EINVAL;
}
ifa->ifa_flags |= IFA_F_SECONDARY;
}
}
if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
net_srandom(ifa->ifa_local);
ifap = last_primary;
}
ifa->ifa_next = *ifap;
*ifap = ifa;
/* Send message first, then call notifier.
Notifier will trigger FIB update, so that
listeners of netlink will know about new ifaddr */
rtmsg_ifa(RTM_NEWADDR, ifa);
blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
return 0;
}
static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
{
struct in_device *in_dev = __in_dev_get_rtnl(dev);
ASSERT_RTNL();
if (!in_dev) {
in_dev = inetdev_init(dev);
if (!in_dev) {
inet_free_ifa(ifa);
return -ENOBUFS;
}
}
if (ifa->ifa_dev != in_dev) {
BUG_TRAP(!ifa->ifa_dev);
in_dev_hold(in_dev);
ifa->ifa_dev = in_dev;
}
if (LOOPBACK(ifa->ifa_local))
ifa->ifa_scope = RT_SCOPE_HOST;
return inet_insert_ifa(ifa);
}
struct in_device *inetdev_by_index(int ifindex)
{
struct net_device *dev;
struct in_device *in_dev = NULL;
read_lock(&dev_base_lock);
dev = __dev_get_by_index(ifindex);
if (dev)
in_dev = in_dev_get(dev);
read_unlock(&dev_base_lock);
return in_dev;
}
/* Called only from RTNL semaphored context. No locks. */
struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, u32 prefix,
u32 mask)
{
ASSERT_RTNL();
for_primary_ifa(in_dev) {
if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
return ifa;
} endfor_ifa(in_dev);
return NULL;
}
static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct rtattr **rta = arg;
struct in_device *in_dev;
struct ifaddrmsg *ifm = NLMSG_DATA(nlh);
struct in_ifaddr *ifa, **ifap;
ASSERT_RTNL();
if ((in_dev = inetdev_by_index(ifm->ifa_index)) == NULL)
goto out;
__in_dev_put(in_dev);
for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
ifap = &ifa->ifa_next) {
if ((rta[IFA_LOCAL - 1] &&
memcmp(RTA_DATA(rta[IFA_LOCAL - 1]),
&ifa->ifa_local, 4)) ||
(rta[IFA_LABEL - 1] &&
rtattr_strcmp(rta[IFA_LABEL - 1], ifa->ifa_label)) ||
(rta[IFA_ADDRESS - 1] &&
(ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
!inet_ifa_match(*(u32*)RTA_DATA(rta[IFA_ADDRESS - 1]),
ifa))))
continue;
inet_del_ifa(in_dev, ifap, 1);
return 0;
}
out:
return -EADDRNOTAVAIL;
}
static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct rtattr **rta = arg;
struct net_device *dev;
struct in_device *in_dev;
struct ifaddrmsg *ifm = NLMSG_DATA(nlh);
struct in_ifaddr *ifa;
int rc = -EINVAL;
ASSERT_RTNL();
if (ifm->ifa_prefixlen > 32 || !rta[IFA_LOCAL - 1])
goto out;
rc = -ENODEV;
if ((dev = __dev_get_by_index(ifm->ifa_index)) == NULL)
goto out;
rc = -ENOBUFS;
if ((in_dev = __in_dev_get_rtnl(dev)) == NULL) {
in_dev = inetdev_init(dev);
if (!in_dev)
goto out;
}
if ((ifa = inet_alloc_ifa()) == NULL)
goto out;
if (!rta[IFA_ADDRESS - 1])
rta[IFA_ADDRESS - 1] = rta[IFA_LOCAL - 1];
memcpy(&ifa->ifa_local, RTA_DATA(rta[IFA_LOCAL - 1]), 4);
memcpy(&ifa->ifa_address, RTA_DATA(rta[IFA_ADDRESS - 1]), 4);
ifa->ifa_prefixlen = ifm->ifa_prefixlen;
ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
if (rta[IFA_BROADCAST - 1])
memcpy(&ifa->ifa_broadcast,
RTA_DATA(rta[IFA_BROADCAST - 1]), 4);
if (rta[IFA_ANYCAST - 1])
memcpy(&ifa->ifa_anycast, RTA_DATA(rta[IFA_ANYCAST - 1]), 4);
ifa->ifa_flags = ifm->ifa_flags;
ifa->ifa_scope = ifm->ifa_scope;
in_dev_hold(in_dev);
ifa->ifa_dev = in_dev;
if (rta[IFA_LABEL - 1])
rtattr_strlcpy(ifa->ifa_label, rta[IFA_LABEL - 1], IFNAMSIZ);
else
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
rc = inet_insert_ifa(ifa);
out:
return rc;
}
/*
* Determine a default network mask, based on the IP address.
*/
static __inline__ int inet_abc_len(u32 addr)
{
int rc = -1; /* Something else, probably a multicast. */
if (ZERONET(addr))
rc = 0;
else {
addr = ntohl(addr);
if (IN_CLASSA(addr))
rc = 8;
else if (IN_CLASSB(addr))
rc = 16;
else if (IN_CLASSC(addr))
rc = 24;
}
return rc;
}
int devinet_ioctl(unsigned int cmd, void __user *arg)
{
struct ifreq ifr;
struct sockaddr_in sin_orig;
struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
struct in_device *in_dev;
struct in_ifaddr **ifap = NULL;
struct in_ifaddr *ifa = NULL;
struct net_device *dev;
char *colon;
int ret = -EFAULT;
int tryaddrmatch = 0;
/*
* Fetch the caller's info block into kernel space
*/
if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
goto out;
ifr.ifr_name[IFNAMSIZ - 1] = 0;
/* save original address for comparison */
memcpy(&sin_orig, sin, sizeof(*sin));
colon = strchr(ifr.ifr_name, ':');
if (colon)
*colon = 0;
#ifdef CONFIG_KMOD
dev_load(ifr.ifr_name);
#endif
switch(cmd) {
case SIOCGIFADDR: /* Get interface address */
case SIOCGIFBRDADDR: /* Get the broadcast address */
case SIOCGIFDSTADDR: /* Get the destination address */
case SIOCGIFNETMASK: /* Get the netmask for the interface */
/* Note that these ioctls will not sleep,
so that we do not impose a lock.
One day we will be forced to put shlock here (I mean SMP)
*/
tryaddrmatch = (sin_orig.sin_family == AF_INET);
memset(sin, 0, sizeof(*sin));
sin->sin_family = AF_INET;
break;
case SIOCSIFFLAGS:
ret = -EACCES;
if (!capable(CAP_NET_ADMIN))
goto out;
break;
case SIOCSIFADDR: /* Set interface address (and family) */
case SIOCSIFBRDADDR: /* Set the broadcast address */
case SIOCSIFDSTADDR: /* Set the destination address */
case SIOCSIFNETMASK: /* Set the netmask for the interface */
ret = -EACCES;
if (!capable(CAP_NET_ADMIN))
goto out;
ret = -EINVAL;
if (sin->sin_family != AF_INET)
goto out;
break;
default:
ret = -EINVAL;
goto out;
}
rtnl_lock();
ret = -ENODEV;
if ((dev = __dev_get_by_name(ifr.ifr_name)) == NULL)
goto done;
if (colon)
*colon = ':';
if ((in_dev = __in_dev_get_rtnl(dev)) != NULL) {
if (tryaddrmatch) {
/* Matthias Andree */
/* compare label and address (4.4BSD style) */
/* note: we only do this for a limited set of ioctls
and only if the original address family was AF_INET.
This is checked above. */
for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
ifap = &ifa->ifa_next) {
if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
sin_orig.sin_addr.s_addr ==
ifa->ifa_address) {
break; /* found */
}
}
}
/* we didn't get a match, maybe the application is
4.3BSD-style and passed in junk so we fall back to
comparing just the label */
if (!ifa) {
for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
ifap = &ifa->ifa_next)
if (!strcmp(ifr.ifr_name, ifa->ifa_label))
break;
}
}
ret = -EADDRNOTAVAIL;
if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
goto done;
switch(cmd) {
case SIOCGIFADDR: /* Get interface address */
sin->sin_addr.s_addr = ifa->ifa_local;
goto rarok;
case SIOCGIFBRDADDR: /* Get the broadcast address */
sin->sin_addr.s_addr = ifa->ifa_broadcast;
goto rarok;
case SIOCGIFDSTADDR: /* Get the destination address */
sin->sin_addr.s_addr = ifa->ifa_address;
goto rarok;
case SIOCGIFNETMASK: /* Get the netmask for the interface */
sin->sin_addr.s_addr = ifa->ifa_mask;
goto rarok;
case SIOCSIFFLAGS:
if (colon) {
ret = -EADDRNOTAVAIL;
if (!ifa)
break;
ret = 0;
if (!(ifr.ifr_flags & IFF_UP))
inet_del_ifa(in_dev, ifap, 1);
break;
}
ret = dev_change_flags(dev, ifr.ifr_flags);
break;
case SIOCSIFADDR: /* Set interface address (and family) */
ret = -EINVAL;
if (inet_abc_len(sin->sin_addr.s_addr) < 0)
break;
if (!ifa) {
ret = -ENOBUFS;
if ((ifa = inet_alloc_ifa()) == NULL)
break;
if (colon)
memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
else
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
} else {
ret = 0;
if (ifa->ifa_local == sin->sin_addr.s_addr)
break;
inet_del_ifa(in_dev, ifap, 0);
ifa->ifa_broadcast = 0;
ifa->ifa_anycast = 0;
}
ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
if (!(dev->flags & IFF_POINTOPOINT)) {
ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
if ((dev->flags & IFF_BROADCAST) &&
ifa->ifa_prefixlen < 31)
ifa->ifa_broadcast = ifa->ifa_address |
~ifa->ifa_mask;
} else {
ifa->ifa_prefixlen = 32;
ifa->ifa_mask = inet_make_mask(32);
}
ret = inet_set_ifa(dev, ifa);
break;
case SIOCSIFBRDADDR: /* Set the broadcast address */
ret = 0;
if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
inet_del_ifa(in_dev, ifap, 0);
ifa->ifa_broadcast = sin->sin_addr.s_addr;
inet_insert_ifa(ifa);
}
break;
case SIOCSIFDSTADDR: /* Set the destination address */
ret = 0;
if (ifa->ifa_address == sin->sin_addr.s_addr)
break;
ret = -EINVAL;
if (inet_abc_len(sin->sin_addr.s_addr) < 0)
break;
ret = 0;
inet_del_ifa(in_dev, ifap, 0);
ifa->ifa_address = sin->sin_addr.s_addr;
inet_insert_ifa(ifa);
break;
case SIOCSIFNETMASK: /* Set the netmask for the interface */
/*
* The mask we set must be legal.
*/
ret = -EINVAL;
if (bad_mask(sin->sin_addr.s_addr, 0))
break;
ret = 0;
if (ifa->ifa_mask != sin->sin_addr.s_addr) {
u32 old_mask = ifa->ifa_mask;
inet_del_ifa(in_dev, ifap, 0);
ifa->ifa_mask = sin->sin_addr.s_addr;
ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
/* See if current broadcast address matches
* with current netmask, then recalculate
* the broadcast address. Otherwise it's a
* funny address, so don't touch it since
* the user seems to know what (s)he's doing...
*/
if ((dev->flags & IFF_BROADCAST) &&
(ifa->ifa_prefixlen < 31) &&
(ifa->ifa_broadcast ==
(ifa->ifa_local|~old_mask))) {
ifa->ifa_broadcast = (ifa->ifa_local |
~sin->sin_addr.s_addr);
}
inet_insert_ifa(ifa);
}
break;
}
done:
rtnl_unlock();
out:
return ret;
rarok:
rtnl_unlock();
ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
goto out;
}
static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
{
struct in_device *in_dev = __in_dev_get_rtnl(dev);
struct in_ifaddr *ifa;
struct ifreq ifr;
int done = 0;
if (!in_dev || (ifa = in_dev->ifa_list) == NULL)
goto out;
for (; ifa; ifa = ifa->ifa_next) {
if (!buf) {
done += sizeof(ifr);
continue;
}
if (len < (int) sizeof(ifr))
break;
memset(&ifr, 0, sizeof(struct ifreq));
if (ifa->ifa_label)
strcpy(ifr.ifr_name, ifa->ifa_label);
else
strcpy(ifr.ifr_name, dev->name);
(*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
(*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
ifa->ifa_local;
if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
done = -EFAULT;
break;
}
buf += sizeof(struct ifreq);
len -= sizeof(struct ifreq);
done += sizeof(struct ifreq);
}
out:
return done;
}
u32 inet_select_addr(const struct net_device *dev, u32 dst, int scope)
{
u32 addr = 0;
struct in_device *in_dev;
rcu_read_lock();
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
goto no_in_dev;
for_primary_ifa(in_dev) {
if (ifa->ifa_scope > scope)
continue;
if (!dst || inet_ifa_match(dst, ifa)) {
addr = ifa->ifa_local;
break;
}
if (!addr)
addr = ifa->ifa_local;
} endfor_ifa(in_dev);
no_in_dev:
rcu_read_unlock();
if (addr)
goto out;
/* Not loopback addresses on loopback should be preferred
in this case. It is importnat that lo is the first interface
in dev_base list.
*/
read_lock(&dev_base_lock);
rcu_read_lock();
for (dev = dev_base; dev; dev = dev->next) {
if ((in_dev = __in_dev_get_rcu(dev)) == NULL)
continue;
for_primary_ifa(in_dev) {
if (ifa->ifa_scope != RT_SCOPE_LINK &&
ifa->ifa_scope <= scope) {
addr = ifa->ifa_local;
goto out_unlock_both;
}
} endfor_ifa(in_dev);
}
out_unlock_both:
read_unlock(&dev_base_lock);
rcu_read_unlock();
out:
return addr;
}
static u32 confirm_addr_indev(struct in_device *in_dev, u32 dst,
u32 local, int scope)
{
int same = 0;
u32 addr = 0;
for_ifa(in_dev) {
if (!addr &&
(local == ifa->ifa_local || !local) &&
ifa->ifa_scope <= scope) {
addr = ifa->ifa_local;
if (same)
break;
}
if (!same) {
same = (!local || inet_ifa_match(local, ifa)) &&
(!dst || inet_ifa_match(dst, ifa));
if (same && addr) {
if (local || !dst)
break;
/* Is the selected addr into dst subnet? */
if (inet_ifa_match(addr, ifa))
break;
/* No, then can we use new local src? */
if (ifa->ifa_scope <= scope) {
addr = ifa->ifa_local;
break;
}
/* search for large dst subnet for addr */
same = 0;
}
}
} endfor_ifa(in_dev);
return same? addr : 0;
}
/*
* Confirm that local IP address exists using wildcards:
* - dev: only on this interface, 0=any interface
* - dst: only in the same subnet as dst, 0=any dst
* - local: address, 0=autoselect the local address
* - scope: maximum allowed scope value for the local address
*/
u32 inet_confirm_addr(const struct net_device *dev, u32 dst, u32 local, int scope)
{
u32 addr = 0;
struct in_device *in_dev;
if (dev) {
rcu_read_lock();
if ((in_dev = __in_dev_get_rcu(dev)))
addr = confirm_addr_indev(in_dev, dst, local, scope);
rcu_read_unlock();
return addr;
}
read_lock(&dev_base_lock);
rcu_read_lock();
for (dev = dev_base; dev; dev = dev->next) {
if ((in_dev = __in_dev_get_rcu(dev))) {
addr = confirm_addr_indev(in_dev, dst, local, scope);
if (addr)
break;
}
}
rcu_read_unlock();
read_unlock(&dev_base_lock);
return addr;
}
/*
* Device notifier
*/
int register_inetaddr_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&inetaddr_chain, nb);
}
int unregister_inetaddr_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
}
/* Rename ifa_labels for a device name change. Make some effort to preserve existing
* alias numbering and to create unique labels if possible.
*/
static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
{
struct in_ifaddr *ifa;
int named = 0;
for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
char old[IFNAMSIZ], *dot;
memcpy(old, ifa->ifa_label, IFNAMSIZ);
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
if (named++ == 0)
continue;
dot = strchr(ifa->ifa_label, ':');
if (dot == NULL) {
sprintf(old, ":%d", named);
dot = old;
}
if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) {
strcat(ifa->ifa_label, dot);
} else {
strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
}
}
}
/* Called only under RTNL semaphore */
static int inetdev_event(struct notifier_block *this, unsigned long event,
void *ptr)
{
struct net_device *dev = ptr;
struct in_device *in_dev = __in_dev_get_rtnl(dev);
ASSERT_RTNL();
if (!in_dev) {
if (event == NETDEV_REGISTER && dev == &loopback_dev) {
in_dev = inetdev_init(dev);
if (!in_dev)
panic("devinet: Failed to create loopback\n");
in_dev->cnf.no_xfrm = 1;
in_dev->cnf.no_policy = 1;
}
goto out;
}
switch (event) {
case NETDEV_REGISTER:
printk(KERN_DEBUG "inetdev_event: bug\n");
dev->ip_ptr = NULL;
break;
case NETDEV_UP:
if (dev->mtu < 68)
break;
if (dev == &loopback_dev) {
struct in_ifaddr *ifa;
if ((ifa = inet_alloc_ifa()) != NULL) {
ifa->ifa_local =
ifa->ifa_address = htonl(INADDR_LOOPBACK);
ifa->ifa_prefixlen = 8;
ifa->ifa_mask = inet_make_mask(8);
in_dev_hold(in_dev);
ifa->ifa_dev = in_dev;
ifa->ifa_scope = RT_SCOPE_HOST;
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
inet_insert_ifa(ifa);
}
}
ip_mc_up(in_dev);
break;
case NETDEV_DOWN:
ip_mc_down(in_dev);
break;
case NETDEV_CHANGEMTU:
if (dev->mtu >= 68)
break;
/* MTU falled under 68, disable IP */
case NETDEV_UNREGISTER:
inetdev_destroy(in_dev);
break;
case NETDEV_CHANGENAME:
/* Do not notify about label change, this event is
* not interesting to applications using netlink.
*/
inetdev_changename(dev, in_dev);
#ifdef CONFIG_SYSCTL
devinet_sysctl_unregister(&in_dev->cnf);
neigh_sysctl_unregister(in_dev->arp_parms);
neigh_sysctl_register(dev, in_dev->arp_parms, NET_IPV4,
NET_IPV4_NEIGH, "ipv4", NULL, NULL);
devinet_sysctl_register(in_dev, &in_dev->cnf);
#endif
break;
}
out:
return NOTIFY_DONE;
}
static struct notifier_block ip_netdev_notifier = {
.notifier_call =inetdev_event,
};
static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
u32 pid, u32 seq, int event, unsigned int flags)
{
struct ifaddrmsg *ifm;
struct nlmsghdr *nlh;
unsigned char *b = skb->tail;
nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*ifm), flags);
ifm = NLMSG_DATA(nlh);
ifm->ifa_family = AF_INET;
ifm->ifa_prefixlen = ifa->ifa_prefixlen;
ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT;
ifm->ifa_scope = ifa->ifa_scope;
ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
if (ifa->ifa_address)
RTA_PUT(skb, IFA_ADDRESS, 4, &ifa->ifa_address);
if (ifa->ifa_local)
RTA_PUT(skb, IFA_LOCAL, 4, &ifa->ifa_local);
if (ifa->ifa_broadcast)
RTA_PUT(skb, IFA_BROADCAST, 4, &ifa->ifa_broadcast);
if (ifa->ifa_anycast)
RTA_PUT(skb, IFA_ANYCAST, 4, &ifa->ifa_anycast);
if (ifa->ifa_label[0])
RTA_PUT(skb, IFA_LABEL, IFNAMSIZ, &ifa->ifa_label);
nlh->nlmsg_len = skb->tail - b;
return skb->len;
nlmsg_failure:
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
{
int idx, ip_idx;
struct net_device *dev;
struct in_device *in_dev;
struct in_ifaddr *ifa;
int s_ip_idx, s_idx = cb->args[0];
s_ip_idx = ip_idx = cb->args[1];
read_lock(&dev_base_lock);
for (dev = dev_base, idx = 0; dev; dev = dev->next, idx++) {
if (idx < s_idx)
continue;
if (idx > s_idx)
s_ip_idx = 0;
rcu_read_lock();
if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
rcu_read_unlock();
continue;
}
for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
ifa = ifa->ifa_next, ip_idx++) {
if (ip_idx < s_ip_idx)
continue;
if (inet_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq,
RTM_NEWADDR, NLM_F_MULTI) <= 0) {
rcu_read_unlock();
goto done;
}
}
rcu_read_unlock();
}
done:
read_unlock(&dev_base_lock);
cb->args[0] = idx;
cb->args[1] = ip_idx;
return skb->len;
}
static void rtmsg_ifa(int event, struct in_ifaddr* ifa)
{
int size = NLMSG_SPACE(sizeof(struct ifaddrmsg) + 128);
struct sk_buff *skb = alloc_skb(size, GFP_KERNEL);
if (!skb)
netlink_set_err(rtnl, 0, RTNLGRP_IPV4_IFADDR, ENOBUFS);
else if (inet_fill_ifaddr(skb, ifa, 0, 0, event, 0) < 0) {
kfree_skb(skb);
netlink_set_err(rtnl, 0, RTNLGRP_IPV4_IFADDR, EINVAL);
} else {
netlink_broadcast(rtnl, skb, 0, RTNLGRP_IPV4_IFADDR, GFP_KERNEL);
}
}
static struct rtnetlink_link inet_rtnetlink_table[RTM_NR_MSGTYPES] = {
[RTM_NEWADDR - RTM_BASE] = { .doit = inet_rtm_newaddr, },
[RTM_DELADDR - RTM_BASE] = { .doit = inet_rtm_deladdr, },
[RTM_GETADDR - RTM_BASE] = { .dumpit = inet_dump_ifaddr, },
[RTM_NEWROUTE - RTM_BASE] = { .doit = inet_rtm_newroute, },
[RTM_DELROUTE - RTM_BASE] = { .doit = inet_rtm_delroute, },
[RTM_GETROUTE - RTM_BASE] = { .doit = inet_rtm_getroute,
.dumpit = inet_dump_fib, },
#ifdef CONFIG_IP_MULTIPLE_TABLES
[RTM_NEWRULE - RTM_BASE] = { .doit = inet_rtm_newrule, },
[RTM_DELRULE - RTM_BASE] = { .doit = inet_rtm_delrule, },
[RTM_GETRULE - RTM_BASE] = { .dumpit = inet_dump_rules, },
#endif
};
#ifdef CONFIG_SYSCTL
void inet_forward_change(void)
{
struct net_device *dev;
int on = ipv4_devconf.forwarding;
ipv4_devconf.accept_redirects = !on;
ipv4_devconf_dflt.forwarding = on;
read_lock(&dev_base_lock);
for (dev = dev_base; dev; dev = dev->next) {
struct in_device *in_dev;
rcu_read_lock();
in_dev = __in_dev_get_rcu(dev);
if (in_dev)
in_dev->cnf.forwarding = on;
rcu_read_unlock();
}
read_unlock(&dev_base_lock);
rt_cache_flush(0);
}
static int devinet_sysctl_forward(ctl_table *ctl, int write,
struct file* filp, void __user *buffer,
size_t *lenp, loff_t *ppos)
{
int *valp = ctl->data;
int val = *valp;
int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
if (write && *valp != val) {
if (valp == &ipv4_devconf.forwarding)
inet_forward_change();
else if (valp != &ipv4_devconf_dflt.forwarding)
rt_cache_flush(0);
}
return ret;
}
int ipv4_doint_and_flush(ctl_table *ctl, int write,
struct file* filp, void __user *buffer,
size_t *lenp, loff_t *ppos)
{
int *valp = ctl->data;
int val = *valp;
int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
if (write && *valp != val)
rt_cache_flush(0);
return ret;
}
int ipv4_doint_and_flush_strategy(ctl_table *table, int __user *name, int nlen,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen,
void **context)
{
int *valp = table->data;
int new;
if (!newval || !newlen)
return 0;
if (newlen != sizeof(int))
return -EINVAL;
if (get_user(new, (int __user *)newval))
return -EFAULT;
if (new == *valp)
return 0;
if (oldval && oldlenp) {
size_t len;
if (get_user(len, oldlenp))
return -EFAULT;
if (len) {
if (len > table->maxlen)
len = table->maxlen;
if (copy_to_user(oldval, valp, len))
return -EFAULT;
if (put_user(len, oldlenp))
return -EFAULT;
}
}
*valp = new;
rt_cache_flush(0);
return 1;
}
static struct devinet_sysctl_table {
struct ctl_table_header *sysctl_header;
ctl_table devinet_vars[__NET_IPV4_CONF_MAX];
ctl_table devinet_dev[2];
ctl_table devinet_conf_dir[2];
ctl_table devinet_proto_dir[2];
ctl_table devinet_root_dir[2];
} devinet_sysctl = {
.devinet_vars = {
{
.ctl_name = NET_IPV4_CONF_FORWARDING,
.procname = "forwarding",
.data = &ipv4_devconf.forwarding,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &devinet_sysctl_forward,
},
{
.ctl_name = NET_IPV4_CONF_MC_FORWARDING,
.procname = "mc_forwarding",
.data = &ipv4_devconf.mc_forwarding,
.maxlen = sizeof(int),
.mode = 0444,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_ACCEPT_REDIRECTS,
.procname = "accept_redirects",
.data = &ipv4_devconf.accept_redirects,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_SECURE_REDIRECTS,
.procname = "secure_redirects",
.data = &ipv4_devconf.secure_redirects,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_SHARED_MEDIA,
.procname = "shared_media",
.data = &ipv4_devconf.shared_media,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_RP_FILTER,
.procname = "rp_filter",
.data = &ipv4_devconf.rp_filter,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_SEND_REDIRECTS,
.procname = "send_redirects",
.data = &ipv4_devconf.send_redirects,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_ACCEPT_SOURCE_ROUTE,
.procname = "accept_source_route",
.data = &ipv4_devconf.accept_source_route,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_PROXY_ARP,
.procname = "proxy_arp",
.data = &ipv4_devconf.proxy_arp,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_MEDIUM_ID,
.procname = "medium_id",
.data = &ipv4_devconf.medium_id,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_BOOTP_RELAY,
.procname = "bootp_relay",
.data = &ipv4_devconf.bootp_relay,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_LOG_MARTIANS,
.procname = "log_martians",
.data = &ipv4_devconf.log_martians,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_TAG,
.procname = "tag",
.data = &ipv4_devconf.tag,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_ARPFILTER,
.procname = "arp_filter",
.data = &ipv4_devconf.arp_filter,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_ARP_ANNOUNCE,
.procname = "arp_announce",
.data = &ipv4_devconf.arp_announce,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_ARP_IGNORE,
.procname = "arp_ignore",
.data = &ipv4_devconf.arp_ignore,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_ARP_ACCEPT,
.procname = "arp_accept",
.data = &ipv4_devconf.arp_accept,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = NET_IPV4_CONF_NOXFRM,
.procname = "disable_xfrm",
.data = &ipv4_devconf.no_xfrm,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &ipv4_doint_and_flush,
.strategy = &ipv4_doint_and_flush_strategy,
},
{
.ctl_name = NET_IPV4_CONF_NOPOLICY,
.procname = "disable_policy",
.data = &ipv4_devconf.no_policy,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &ipv4_doint_and_flush,
.strategy = &ipv4_doint_and_flush_strategy,
},
{
.ctl_name = NET_IPV4_CONF_FORCE_IGMP_VERSION,
.procname = "force_igmp_version",
.data = &ipv4_devconf.force_igmp_version,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &ipv4_doint_and_flush,
.strategy = &ipv4_doint_and_flush_strategy,
},
{
.ctl_name = NET_IPV4_CONF_PROMOTE_SECONDARIES,
.procname = "promote_secondaries",
.data = &ipv4_devconf.promote_secondaries,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &ipv4_doint_and_flush,
.strategy = &ipv4_doint_and_flush_strategy,
},
},
.devinet_dev = {
{
.ctl_name = NET_PROTO_CONF_ALL,
.procname = "all",
.mode = 0555,
.child = devinet_sysctl.devinet_vars,
},
},
.devinet_conf_dir = {
{
.ctl_name = NET_IPV4_CONF,
.procname = "conf",
.mode = 0555,
.child = devinet_sysctl.devinet_dev,
},
},
.devinet_proto_dir = {
{
.ctl_name = NET_IPV4,
.procname = "ipv4",
.mode = 0555,
.child = devinet_sysctl.devinet_conf_dir,
},
},
.devinet_root_dir = {
{
.ctl_name = CTL_NET,
.procname = "net",
.mode = 0555,
.child = devinet_sysctl.devinet_proto_dir,
},
},
};
static void devinet_sysctl_register(struct in_device *in_dev,
struct ipv4_devconf *p)
{
int i;
struct net_device *dev = in_dev ? in_dev->dev : NULL;
struct devinet_sysctl_table *t = kmalloc(sizeof(*t), GFP_KERNEL);
char *dev_name = NULL;
if (!t)
return;
memcpy(t, &devinet_sysctl, sizeof(*t));
for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
t->devinet_vars[i].de = NULL;
}
if (dev) {
dev_name = dev->name;
t->devinet_dev[0].ctl_name = dev->ifindex;
} else {
dev_name = "default";
t->devinet_dev[0].ctl_name = NET_PROTO_CONF_DEFAULT;
}
/*
* Make a copy of dev_name, because '.procname' is regarded as const
* by sysctl and we wouldn't want anyone to change it under our feet
* (see SIOCSIFNAME).
*/
dev_name = kstrdup(dev_name, GFP_KERNEL);
if (!dev_name)
goto free;
t->devinet_dev[0].procname = dev_name;
t->devinet_dev[0].child = t->devinet_vars;
t->devinet_dev[0].de = NULL;
t->devinet_conf_dir[0].child = t->devinet_dev;
t->devinet_conf_dir[0].de = NULL;
t->devinet_proto_dir[0].child = t->devinet_conf_dir;
t->devinet_proto_dir[0].de = NULL;
t->devinet_root_dir[0].child = t->devinet_proto_dir;
t->devinet_root_dir[0].de = NULL;
t->sysctl_header = register_sysctl_table(t->devinet_root_dir, 0);
if (!t->sysctl_header)
goto free_procname;
p->sysctl = t;
return;
/* error path */
free_procname:
kfree(dev_name);
free:
kfree(t);
return;
}
static void devinet_sysctl_unregister(struct ipv4_devconf *p)
{
if (p->sysctl) {
struct devinet_sysctl_table *t = p->sysctl;
p->sysctl = NULL;
unregister_sysctl_table(t->sysctl_header);
kfree(t->devinet_dev[0].procname);
kfree(t);
}
}
#endif
void __init devinet_init(void)
{
register_gifconf(PF_INET, inet_gifconf);
register_netdevice_notifier(&ip_netdev_notifier);
rtnetlink_links[PF_INET] = inet_rtnetlink_table;
#ifdef CONFIG_SYSCTL
devinet_sysctl.sysctl_header =
register_sysctl_table(devinet_sysctl.devinet_root_dir, 0);
devinet_sysctl_register(NULL, &ipv4_devconf_dflt);
#endif
}
EXPORT_SYMBOL(in_dev_finish_destroy);
EXPORT_SYMBOL(inet_select_addr);
EXPORT_SYMBOL(inetdev_by_index);
EXPORT_SYMBOL(register_inetaddr_notifier);
EXPORT_SYMBOL(unregister_inetaddr_notifier);
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