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devinet.c
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/*
* NET3 IP device support routines.
*
* 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, <[email protected]>
* Mark Evans, <[email protected]>
*
* Additional Authors:
* Alan Cox, <[email protected]>
* Alexey Kuznetsov, <[email protected]>
*
* 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/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_addr.h>
#include <linux/if_ether.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/notifier.h>
#include <linux/inetdevice.h>
#include <linux/igmp.h>
#include <linux/slab.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>
#include <net/rtnetlink.h>
#include <net/net_namespace.h>
static struct ipv4_devconf ipv4_devconf = {
.data = {
[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
[IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
[IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
[IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
},
};
static struct ipv4_devconf ipv4_devconf_dflt = {
.data = {
[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
[IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
[IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
[IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
[IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
},
};
#define IPV4_DEVCONF_DFLT(net, attr) \
IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
[IFA_LOCAL] = { .type = NLA_U32 },
[IFA_ADDRESS] = { .type = NLA_U32 },
[IFA_BROADCAST] = { .type = NLA_U32 },
[IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
};
static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
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 *idev);
static void devinet_sysctl_unregister(struct in_device *idev);
#else
static inline void devinet_sysctl_register(struct in_device *idev)
{
}
static inline void devinet_sysctl_unregister(struct in_device *idev)
{
}
#endif
/* Locks all the inet devices. */
static struct in_ifaddr *inet_alloc_ifa(void)
{
return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL);
}
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;
WARN_ON(idev->ifa_list);
WARN_ON(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)
pr_err("Freeing alive in_device %p\n", idev);
else
kfree(idev);
}
EXPORT_SYMBOL(in_dev_finish_destroy);
static struct in_device *inetdev_init(struct net_device *dev)
{
struct in_device *in_dev;
ASSERT_RTNL();
in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
if (!in_dev)
goto out;
memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
sizeof(in_dev->cnf));
in_dev->cnf.sysctl = NULL;
in_dev->dev = dev;
in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
if (!in_dev->arp_parms)
goto out_kfree;
if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
dev_disable_lro(dev);
/* Reference in_dev->dev */
dev_hold(dev);
/* Account for reference dev->ip_ptr (below) */
in_dev_hold(in_dev);
devinet_sysctl_register(in_dev);
ip_mc_init_dev(in_dev);
if (dev->flags & IFF_UP)
ip_mc_up(in_dev);
/* we can receive as soon as ip_ptr is set -- do this last */
rcu_assign_pointer(dev->ip_ptr, 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;
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);
}
rcu_assign_pointer(dev->ip_ptr, NULL);
devinet_sysctl_unregister(in_dev);
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, __be32 a, __be32 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 nlmsghdr *nlh, u32 pid)
{
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, nlh, pid);
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, nlh, pid);
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, nlh, pid);
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);
}
static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
int destroy)
{
__inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
}
static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
u32 pid)
{
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, nlh, pid);
blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
return 0;
}
static int inet_insert_ifa(struct in_ifaddr *ifa)
{
return __inet_insert_ifa(ifa, NULL, 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) {
inet_free_ifa(ifa);
return -ENOBUFS;
}
ipv4_devconf_setall(in_dev);
if (ifa->ifa_dev != in_dev) {
WARN_ON(ifa->ifa_dev);
in_dev_hold(in_dev);
ifa->ifa_dev = in_dev;
}
if (ipv4_is_loopback(ifa->ifa_local))
ifa->ifa_scope = RT_SCOPE_HOST;
return inet_insert_ifa(ifa);
}
/* Caller must hold RCU or RTNL :
* We dont take a reference on found in_device
*/
struct in_device *inetdev_by_index(struct net *net, int ifindex)
{
struct net_device *dev;
struct in_device *in_dev = NULL;
rcu_read_lock();
dev = dev_get_by_index_rcu(net, ifindex);
if (dev)
in_dev = rcu_dereference_rtnl(dev->ip_ptr);
rcu_read_unlock();
return in_dev;
}
EXPORT_SYMBOL(inetdev_by_index);
/* Called only from RTNL semaphored context. No locks. */
struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
__be32 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 net *net = sock_net(skb->sk);
struct nlattr *tb[IFA_MAX+1];
struct in_device *in_dev;
struct ifaddrmsg *ifm;
struct in_ifaddr *ifa, **ifap;
int err = -EINVAL;
ASSERT_RTNL();
err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
if (err < 0)
goto errout;
ifm = nlmsg_data(nlh);
in_dev = inetdev_by_index(net, ifm->ifa_index);
if (in_dev == NULL) {
err = -ENODEV;
goto errout;
}
for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
ifap = &ifa->ifa_next) {
if (tb[IFA_LOCAL] &&
ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL]))
continue;
if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
continue;
if (tb[IFA_ADDRESS] &&
(ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
!inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa)))
continue;
__inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid);
return 0;
}
err = -EADDRNOTAVAIL;
errout:
return err;
}
static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh)
{
struct nlattr *tb[IFA_MAX+1];
struct in_ifaddr *ifa;
struct ifaddrmsg *ifm;
struct net_device *dev;
struct in_device *in_dev;
int err;
err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
if (err < 0)
goto errout;
ifm = nlmsg_data(nlh);
err = -EINVAL;
if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL)
goto errout;
dev = __dev_get_by_index(net, ifm->ifa_index);
err = -ENODEV;
if (dev == NULL)
goto errout;
in_dev = __in_dev_get_rtnl(dev);
err = -ENOBUFS;
if (in_dev == NULL)
goto errout;
ifa = inet_alloc_ifa();
if (ifa == NULL)
/*
* A potential indev allocation can be left alive, it stays
* assigned to its device and is destroy with it.
*/
goto errout;
ipv4_devconf_setall(in_dev);
in_dev_hold(in_dev);
if (tb[IFA_ADDRESS] == NULL)
tb[IFA_ADDRESS] = tb[IFA_LOCAL];
ifa->ifa_prefixlen = ifm->ifa_prefixlen;
ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
ifa->ifa_flags = ifm->ifa_flags;
ifa->ifa_scope = ifm->ifa_scope;
ifa->ifa_dev = in_dev;
ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]);
ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]);
if (tb[IFA_BROADCAST])
ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]);
if (tb[IFA_LABEL])
nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
else
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
return ifa;
errout:
return ERR_PTR(err);
}
static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
struct in_ifaddr *ifa;
ASSERT_RTNL();
ifa = rtm_to_ifaddr(net, nlh);
if (IS_ERR(ifa))
return PTR_ERR(ifa);
return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).pid);
}
/*
* Determine a default network mask, based on the IP address.
*/
static inline int inet_abc_len(__be32 addr)
{
int rc = -1; /* Something else, probably a multicast. */
if (ipv4_is_zeronet(addr))
rc = 0;
else {
__u32 haddr = ntohl(addr);
if (IN_CLASSA(haddr))
rc = 8;
else if (IN_CLASSB(haddr))
rc = 16;
else if (IN_CLASSC(haddr))
rc = 24;
}
return rc;
}
int devinet_ioctl(struct net *net, 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;
dev_load(net, ifr.ifr_name);
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;
dev = __dev_get_by_name(net, ifr.ifr_name);
if (!dev)
goto done;
if (colon)
*colon = ':';
in_dev = __in_dev_get_rtnl(dev);
if (in_dev) {
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;
ifa = inet_alloc_ifa();
if (!ifa)
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_scope = 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) {
__be32 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)
goto out;
for (ifa = in_dev->ifa_list; 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;
}
__be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
{
__be32 addr = 0;
struct in_device *in_dev;
struct net *net = dev_net(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);
if (addr)
goto out_unlock;
no_in_dev:
/* Not loopback addresses on loopback should be preferred
in this case. It is importnat that lo is the first interface
in dev_base list.
*/
for_each_netdev_rcu(net, dev) {
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
continue;
for_primary_ifa(in_dev) {
if (ifa->ifa_scope != RT_SCOPE_LINK &&
ifa->ifa_scope <= scope) {
addr = ifa->ifa_local;
goto out_unlock;
}
} endfor_ifa(in_dev);
}
out_unlock:
rcu_read_unlock();
return addr;
}
EXPORT_SYMBOL(inet_select_addr);
static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
__be32 local, int scope)
{
int same = 0;
__be32 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:
* - in_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
*/
__be32 inet_confirm_addr(struct in_device *in_dev,
__be32 dst, __be32 local, int scope)
{
__be32 addr = 0;
struct net_device *dev;
struct net *net;
if (scope != RT_SCOPE_LINK)
return confirm_addr_indev(in_dev, dst, local, scope);
net = dev_net(in_dev->dev);
rcu_read_lock();
for_each_netdev_rcu(net, dev) {
in_dev = __in_dev_get_rcu(dev);
if (in_dev) {
addr = confirm_addr_indev(in_dev, dst, local, scope);
if (addr)
break;
}
}
rcu_read_unlock();
return addr;
}
/*
* Device notifier
*/
int register_inetaddr_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&inetaddr_chain, nb);
}
EXPORT_SYMBOL(register_inetaddr_notifier);
int unregister_inetaddr_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
}
EXPORT_SYMBOL(unregister_inetaddr_notifier);
/* Rename ifa_labels for a device name change. Make some effort to preserve
* existing alias numbering and to create unique labels if possible.