linux/net/ipv4/devinet.c
Eric Dumazet 02e24903e5 netlink: let core handle error cases in dump operations
After commit b5a899154a ("netlink: handle EMSGSIZE errors
in the core"), we can remove some code that was not 100 % correct
anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240306102426.245689-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-07 20:48:22 -08:00

2801 lines
70 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* NET3 IP device support routines.
*
* 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 <linux/uaccess.h>
#include <linux/bitops.h>
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched/signal.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>
#include <linux/hash.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#include <linux/kmod.h>
#include <linux/netconf.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>
#include <net/addrconf.h>
#define IPV6ONLY_FLAGS \
(IFA_F_NODAD | IFA_F_OPTIMISTIC | IFA_F_DADFAILED | \
IFA_F_HOMEADDRESS | IFA_F_TENTATIVE | \
IFA_F_MANAGETEMPADDR | IFA_F_STABLE_PRIVACY)
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,
[IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
[IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/,
[IPV4_DEVCONF_ARP_EVICT_NOCARRIER - 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,
[IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
[IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/,
[IPV4_DEVCONF_ARP_EVICT_NOCARRIER - 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 },
[IFA_CACHEINFO] = { .len = sizeof(struct ifa_cacheinfo) },
[IFA_FLAGS] = { .type = NLA_U32 },
[IFA_RT_PRIORITY] = { .type = NLA_U32 },
[IFA_TARGET_NETNSID] = { .type = NLA_S32 },
[IFA_PROTO] = { .type = NLA_U8 },
};
struct inet_fill_args {
u32 portid;
u32 seq;
int event;
unsigned int flags;
int netnsid;
int ifindex;
};
#define IN4_ADDR_HSIZE_SHIFT 8
#define IN4_ADDR_HSIZE (1U << IN4_ADDR_HSIZE_SHIFT)
static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
static u32 inet_addr_hash(const struct net *net, __be32 addr)
{
u32 val = (__force u32) addr ^ net_hash_mix(net);
return hash_32(val, IN4_ADDR_HSIZE_SHIFT);
}
static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
{
u32 hash = inet_addr_hash(net, ifa->ifa_local);
ASSERT_RTNL();
hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
}
static void inet_hash_remove(struct in_ifaddr *ifa)
{
ASSERT_RTNL();
hlist_del_init_rcu(&ifa->hash);
}
/**
* __ip_dev_find - find the first device with a given source address.
* @net: the net namespace
* @addr: the source address
* @devref: if true, take a reference on the found device
*
* If a caller uses devref=false, it should be protected by RCU, or RTNL
*/
struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
{
struct net_device *result = NULL;
struct in_ifaddr *ifa;
rcu_read_lock();
ifa = inet_lookup_ifaddr_rcu(net, addr);
if (!ifa) {
struct flowi4 fl4 = { .daddr = addr };
struct fib_result res = { 0 };
struct fib_table *local;
/* Fallback to FIB local table so that communication
* over loopback subnets work.
*/
local = fib_get_table(net, RT_TABLE_LOCAL);
if (local &&
!fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
res.type == RTN_LOCAL)
result = FIB_RES_DEV(res);
} else {
result = ifa->ifa_dev->dev;
}
if (result && devref)
dev_hold(result);
rcu_read_unlock();
return result;
}
EXPORT_SYMBOL(__ip_dev_find);
/* called under RCU lock */
struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net, __be32 addr)
{
u32 hash = inet_addr_hash(net, addr);
struct in_ifaddr *ifa;
hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash)
if (ifa->ifa_local == addr &&
net_eq(dev_net(ifa->ifa_dev->dev), net))
return ifa;
return NULL;
}
static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
static BLOCKING_NOTIFIER_HEAD(inetaddr_validator_chain);
static void inet_del_ifa(struct in_device *in_dev,
struct in_ifaddr __rcu **ifap,
int destroy);
#ifdef CONFIG_SYSCTL
static int devinet_sysctl_register(struct in_device *idev);
static void devinet_sysctl_unregister(struct in_device *idev);
#else
static int devinet_sysctl_register(struct in_device *idev)
{
return 0;
}
static 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_ACCOUNT);
}
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 void inet_free_ifa(struct in_ifaddr *ifa)
{
call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
}
static void in_dev_free_rcu(struct rcu_head *head)
{
struct in_device *idev = container_of(head, struct in_device, rcu_head);
kfree(rcu_dereference_protected(idev->mc_hash, 1));
kfree(idev);
}
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
pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL");
#endif
netdev_put(dev, &idev->dev_tracker);
if (!idev->dead)
pr_err("Freeing alive in_device %p\n", idev);
else
call_rcu(&idev->rcu_head, in_dev_free_rcu);
}
EXPORT_SYMBOL(in_dev_finish_destroy);
static struct in_device *inetdev_init(struct net_device *dev)
{
struct in_device *in_dev;
int err = -ENOMEM;
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 */
netdev_hold(dev, &in_dev->dev_tracker, GFP_KERNEL);
/* Account for reference dev->ip_ptr (below) */
refcount_set(&in_dev->refcnt, 1);
err = devinet_sysctl_register(in_dev);
if (err) {
in_dev->dead = 1;
neigh_parms_release(&arp_tbl, in_dev->arp_parms);
in_dev_put(in_dev);
in_dev = NULL;
goto out;
}
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 ?: ERR_PTR(err);
out_kfree:
kfree(in_dev);
in_dev = NULL;
goto out;
}
static void inetdev_destroy(struct in_device *in_dev)
{
struct net_device *dev;
struct in_ifaddr *ifa;
ASSERT_RTNL();
dev = in_dev->dev;
in_dev->dead = 1;
ip_mc_destroy_dev(in_dev);
while ((ifa = rtnl_dereference(in_dev->ifa_list)) != NULL) {
inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
inet_free_ifa(ifa);
}
RCU_INIT_POINTER(dev->ip_ptr, NULL);
devinet_sysctl_unregister(in_dev);
neigh_parms_release(&arp_tbl, in_dev->arp_parms);
arp_ifdown(dev);
in_dev_put(in_dev);
}
int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
{
const struct in_ifaddr *ifa;
rcu_read_lock();
in_dev_for_each_ifa_rcu(ifa, in_dev) {
if (inet_ifa_match(a, ifa)) {
if (!b || inet_ifa_match(b, ifa)) {
rcu_read_unlock();
return 1;
}
}
}
rcu_read_unlock();
return 0;
}
static void __inet_del_ifa(struct in_device *in_dev,
struct in_ifaddr __rcu **ifap,
int destroy, struct nlmsghdr *nlh, u32 portid)
{
struct in_ifaddr *promote = NULL;
struct in_ifaddr *ifa, *ifa1;
struct in_ifaddr __rcu **last_prim;
struct in_ifaddr *prev_prom = NULL;
int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
ASSERT_RTNL();
ifa1 = rtnl_dereference(*ifap);
last_prim = ifap;
if (in_dev->dead)
goto no_promotions;
/* 1. Deleting primary ifaddr forces deletion all secondaries
* unless alias promotion is set
**/
if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
struct in_ifaddr __rcu **ifap1 = &ifa1->ifa_next;
while ((ifa = rtnl_dereference(*ifap1)) != NULL) {
if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
ifa1->ifa_scope <= ifa->ifa_scope)
last_prim = &ifa->ifa_next;
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) {
inet_hash_remove(ifa);
*ifap1 = ifa->ifa_next;
rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid);
blocking_notifier_call_chain(&inetaddr_chain,
NETDEV_DOWN, ifa);
inet_free_ifa(ifa);
} else {
promote = ifa;
break;
}
}
}
/* On promotion all secondaries from subnet are changing
* the primary IP, we must remove all their routes silently
* and later to add them back with new prefsrc. Do this
* while all addresses are on the device list.
*/
for (ifa = promote; ifa; ifa = rtnl_dereference(ifa->ifa_next)) {
if (ifa1->ifa_mask == ifa->ifa_mask &&
inet_ifa_match(ifa1->ifa_address, ifa))
fib_del_ifaddr(ifa, ifa1);
}
no_promotions:
/* 2. Unlink it */
*ifap = ifa1->ifa_next;
inet_hash_remove(ifa1);
/* 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, portid);
blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
if (promote) {
struct in_ifaddr *next_sec;
next_sec = rtnl_dereference(promote->ifa_next);
if (prev_prom) {
struct in_ifaddr *last_sec;
rcu_assign_pointer(prev_prom->ifa_next, next_sec);
last_sec = rtnl_dereference(*last_prim);
rcu_assign_pointer(promote->ifa_next, last_sec);
rcu_assign_pointer(*last_prim, promote);
}
promote->ifa_flags &= ~IFA_F_SECONDARY;
rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
blocking_notifier_call_chain(&inetaddr_chain,
NETDEV_UP, promote);
for (ifa = next_sec; ifa;
ifa = rtnl_dereference(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 __rcu **ifap,
int destroy)
{
__inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
}
static void check_lifetime(struct work_struct *work);
static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
u32 portid, struct netlink_ext_ack *extack)
{
struct in_ifaddr __rcu **last_primary, **ifap;
struct in_device *in_dev = ifa->ifa_dev;
struct in_validator_info ivi;
struct in_ifaddr *ifa1;
int ret;
ASSERT_RTNL();
if (!ifa->ifa_local) {
inet_free_ifa(ifa);
return 0;
}
ifa->ifa_flags &= ~IFA_F_SECONDARY;
last_primary = &in_dev->ifa_list;
/* Don't set IPv6 only flags to IPv4 addresses */
ifa->ifa_flags &= ~IPV6ONLY_FLAGS;
ifap = &in_dev->ifa_list;
ifa1 = rtnl_dereference(*ifap);
while (ifa1) {
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) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid scope value");
inet_free_ifa(ifa);
return -EINVAL;
}
ifa->ifa_flags |= IFA_F_SECONDARY;
}
ifap = &ifa1->ifa_next;
ifa1 = rtnl_dereference(*ifap);
}
/* Allow any devices that wish to register ifaddr validtors to weigh
* in now, before changes are committed. The rntl lock is serializing
* access here, so the state should not change between a validator call
* and a final notify on commit. This isn't invoked on promotion under
* the assumption that validators are checking the address itself, and
* not the flags.
*/
ivi.ivi_addr = ifa->ifa_address;
ivi.ivi_dev = ifa->ifa_dev;
ivi.extack = extack;
ret = blocking_notifier_call_chain(&inetaddr_validator_chain,
NETDEV_UP, &ivi);
ret = notifier_to_errno(ret);
if (ret) {
inet_free_ifa(ifa);
return ret;
}
if (!(ifa->ifa_flags & IFA_F_SECONDARY))
ifap = last_primary;
rcu_assign_pointer(ifa->ifa_next, *ifap);
rcu_assign_pointer(*ifap, ifa);
inet_hash_insert(dev_net(in_dev->dev), ifa);
cancel_delayed_work(&check_lifetime_work);
queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
/* 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, portid);
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, NULL);
}
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);
neigh_parms_data_state_setall(in_dev->arp_parms);
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)
{
struct in_ifaddr *ifa;
ASSERT_RTNL();
in_dev_for_each_ifa_rtnl(ifa, in_dev) {
if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
return ifa;
}
return NULL;
}
static int ip_mc_autojoin_config(struct net *net, bool join,
const struct in_ifaddr *ifa)
{
#if defined(CONFIG_IP_MULTICAST)
struct ip_mreqn mreq = {
.imr_multiaddr.s_addr = ifa->ifa_address,
.imr_ifindex = ifa->ifa_dev->dev->ifindex,
};
struct sock *sk = net->ipv4.mc_autojoin_sk;
int ret;
ASSERT_RTNL();
lock_sock(sk);
if (join)
ret = ip_mc_join_group(sk, &mreq);
else
ret = ip_mc_leave_group(sk, &mreq);
release_sock(sk);
return ret;
#else
return -EOPNOTSUPP;
#endif
}
static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct in_ifaddr __rcu **ifap;
struct nlattr *tb[IFA_MAX+1];
struct in_device *in_dev;
struct ifaddrmsg *ifm;
struct in_ifaddr *ifa;
int err;
ASSERT_RTNL();
err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
ifa_ipv4_policy, extack);
if (err < 0)
goto errout;
ifm = nlmsg_data(nlh);
in_dev = inetdev_by_index(net, ifm->ifa_index);
if (!in_dev) {
NL_SET_ERR_MSG(extack, "ipv4: Device not found");
err = -ENODEV;
goto errout;
}
for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL;
ifap = &ifa->ifa_next) {
if (tb[IFA_LOCAL] &&
ifa->ifa_local != nla_get_in_addr(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_in_addr(tb[IFA_ADDRESS]), ifa)))
continue;
if (ipv4_is_multicast(ifa->ifa_address))
ip_mc_autojoin_config(net, false, ifa);
__inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid);
return 0;
}
NL_SET_ERR_MSG(extack, "ipv4: Address not found");
err = -EADDRNOTAVAIL;
errout:
return err;
}
#define INFINITY_LIFE_TIME 0xFFFFFFFF
static void check_lifetime(struct work_struct *work)
{
unsigned long now, next, next_sec, next_sched;
struct in_ifaddr *ifa;
struct hlist_node *n;
int i;
now = jiffies;
next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
for (i = 0; i < IN4_ADDR_HSIZE; i++) {
bool change_needed = false;
rcu_read_lock();
hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
unsigned long age, tstamp;
u32 preferred_lft;
u32 valid_lft;
u32 flags;
flags = READ_ONCE(ifa->ifa_flags);
if (flags & IFA_F_PERMANENT)
continue;
preferred_lft = READ_ONCE(ifa->ifa_preferred_lft);
valid_lft = READ_ONCE(ifa->ifa_valid_lft);
tstamp = READ_ONCE(ifa->ifa_tstamp);
/* We try to batch several events at once. */
age = (now - tstamp +
ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
if (valid_lft != INFINITY_LIFE_TIME &&
age >= valid_lft) {
change_needed = true;
} else if (preferred_lft ==
INFINITY_LIFE_TIME) {
continue;
} else if (age >= preferred_lft) {
if (time_before(tstamp + valid_lft * HZ, next))
next = tstamp + valid_lft * HZ;
if (!(flags & IFA_F_DEPRECATED))
change_needed = true;
} else if (time_before(tstamp + preferred_lft * HZ,
next)) {
next = tstamp + preferred_lft * HZ;
}
}
rcu_read_unlock();
if (!change_needed)
continue;
rtnl_lock();
hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
unsigned long age;
if (ifa->ifa_flags & IFA_F_PERMANENT)
continue;
/* We try to batch several events at once. */
age = (now - ifa->ifa_tstamp +
ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
age >= ifa->ifa_valid_lft) {
struct in_ifaddr __rcu **ifap;
struct in_ifaddr *tmp;
ifap = &ifa->ifa_dev->ifa_list;
tmp = rtnl_dereference(*ifap);
while (tmp) {
if (tmp == ifa) {
inet_del_ifa(ifa->ifa_dev,
ifap, 1);
break;
}
ifap = &tmp->ifa_next;
tmp = rtnl_dereference(*ifap);
}
} else if (ifa->ifa_preferred_lft !=
INFINITY_LIFE_TIME &&
age >= ifa->ifa_preferred_lft &&
!(ifa->ifa_flags & IFA_F_DEPRECATED)) {
ifa->ifa_flags |= IFA_F_DEPRECATED;
rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
}
}
rtnl_unlock();
}
next_sec = round_jiffies_up(next);
next_sched = next;
/* If rounded timeout is accurate enough, accept it. */
if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
next_sched = next_sec;
now = jiffies;
/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
queue_delayed_work(system_power_efficient_wq, &check_lifetime_work,
next_sched - now);
}
static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
__u32 prefered_lft)
{
unsigned long timeout;
u32 flags;
flags = ifa->ifa_flags & ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);
timeout = addrconf_timeout_fixup(valid_lft, HZ);
if (addrconf_finite_timeout(timeout))
WRITE_ONCE(ifa->ifa_valid_lft, timeout);
else
flags |= IFA_F_PERMANENT;
timeout = addrconf_timeout_fixup(prefered_lft, HZ);
if (addrconf_finite_timeout(timeout)) {
if (timeout == 0)
flags |= IFA_F_DEPRECATED;
WRITE_ONCE(ifa->ifa_preferred_lft, timeout);
}
WRITE_ONCE(ifa->ifa_flags, flags);
WRITE_ONCE(ifa->ifa_tstamp, jiffies);
if (!ifa->ifa_cstamp)
WRITE_ONCE(ifa->ifa_cstamp, ifa->ifa_tstamp);
}
static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
__u32 *pvalid_lft, __u32 *pprefered_lft,
struct netlink_ext_ack *extack)
{
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_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
ifa_ipv4_policy, extack);
if (err < 0)
goto errout;
ifm = nlmsg_data(nlh);
err = -EINVAL;
if (ifm->ifa_prefixlen > 32) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid prefix length");
goto errout;
}
if (!tb[IFA_LOCAL]) {
NL_SET_ERR_MSG(extack, "ipv4: Local address is not supplied");
goto errout;
}
dev = __dev_get_by_index(net, ifm->ifa_index);
err = -ENODEV;
if (!dev) {
NL_SET_ERR_MSG(extack, "ipv4: Device not found");
goto errout;
}
in_dev = __in_dev_get_rtnl(dev);
err = -ENOBUFS;
if (!in_dev)
goto errout;
ifa = inet_alloc_ifa();
if (!ifa)
/*
* 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);
neigh_parms_data_state_setall(in_dev->arp_parms);
in_dev_hold(in_dev);
if (!tb[IFA_ADDRESS])
tb[IFA_ADDRESS] = tb[IFA_LOCAL];
INIT_HLIST_NODE(&ifa->hash);
ifa->ifa_prefixlen = ifm->ifa_prefixlen;
ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
ifm->ifa_flags;
ifa->ifa_scope = ifm->ifa_scope;
ifa->ifa_dev = in_dev;
ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]);
ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]);
if (tb[IFA_BROADCAST])
ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]);
if (tb[IFA_LABEL])
nla_strscpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
else
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
if (tb[IFA_RT_PRIORITY])
ifa->ifa_rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
if (tb[IFA_PROTO])
ifa->ifa_proto = nla_get_u8(tb[IFA_PROTO]);
if (tb[IFA_CACHEINFO]) {
struct ifa_cacheinfo *ci;
ci = nla_data(tb[IFA_CACHEINFO]);
if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) {
NL_SET_ERR_MSG(extack, "ipv4: address lifetime invalid");
err = -EINVAL;
goto errout_free;
}
*pvalid_lft = ci->ifa_valid;
*pprefered_lft = ci->ifa_prefered;
}
return ifa;
errout_free:
inet_free_ifa(ifa);
errout:
return ERR_PTR(err);
}
static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
{
struct in_device *in_dev = ifa->ifa_dev;
struct in_ifaddr *ifa1;
if (!ifa->ifa_local)
return NULL;
in_dev_for_each_ifa_rtnl(ifa1, in_dev) {
if (ifa1->ifa_mask == ifa->ifa_mask &&
inet_ifa_match(ifa1->ifa_address, ifa) &&
ifa1->ifa_local == ifa->ifa_local)
return ifa1;
}
return NULL;
}
static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct in_ifaddr *ifa;
struct in_ifaddr *ifa_existing;
__u32 valid_lft = INFINITY_LIFE_TIME;
__u32 prefered_lft = INFINITY_LIFE_TIME;
ASSERT_RTNL();
ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft, extack);
if (IS_ERR(ifa))
return PTR_ERR(ifa);
ifa_existing = find_matching_ifa(ifa);
if (!ifa_existing) {
/* It would be best to check for !NLM_F_CREATE here but
* userspace already relies on not having to provide this.
*/
set_ifa_lifetime(ifa, valid_lft, prefered_lft);
if (ifa->ifa_flags & IFA_F_MCAUTOJOIN) {
int ret = ip_mc_autojoin_config(net, true, ifa);
if (ret < 0) {
NL_SET_ERR_MSG(extack, "ipv4: Multicast auto join failed");
inet_free_ifa(ifa);
return ret;
}
}
return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid,
extack);
} else {
u32 new_metric = ifa->ifa_rt_priority;
u8 new_proto = ifa->ifa_proto;
inet_free_ifa(ifa);
if (nlh->nlmsg_flags & NLM_F_EXCL ||
!(nlh->nlmsg_flags & NLM_F_REPLACE)) {
NL_SET_ERR_MSG(extack, "ipv4: Address already assigned");
return -EEXIST;
}
ifa = ifa_existing;
if (ifa->ifa_rt_priority != new_metric) {
fib_modify_prefix_metric(ifa, new_metric);
ifa->ifa_rt_priority = new_metric;
}
ifa->ifa_proto = new_proto;
set_ifa_lifetime(ifa, valid_lft, prefered_lft);
cancel_delayed_work(&check_lifetime_work);
queue_delayed_work(system_power_efficient_wq,
&check_lifetime_work, 0);
rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
}
return 0;
}
/*
* Determine a default network mask, based on the IP address.
*/
static int inet_abc_len(__be32 addr)
{
int rc = -1; /* Something else, probably a multicast. */
if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(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;
else if (IN_CLASSE(haddr))
rc = 32;
}
return rc;
}
int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr)
{
struct sockaddr_in sin_orig;
struct sockaddr_in *sin = (struct sockaddr_in *)&ifr->ifr_addr;
struct in_ifaddr __rcu **ifap = NULL;
struct in_device *in_dev;
struct in_ifaddr *ifa = NULL;
struct net_device *dev;
char *colon;
int ret = -EFAULT;
int tryaddrmatch = 0;
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 = -EPERM;
if (!ns_capable(net->user_ns, 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 = -EPERM;
if (!ns_capable(net->user_ns, 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 = rtnl_dereference(*ifap)) != NULL;
ifap = &ifa->ifa_next) {
if (!strcmp(ifr->ifr_name, ifa->ifa_label) &&
sin_orig.sin_addr.s_addr ==
ifa->ifa_local) {
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 = rtnl_dereference(*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 */
ret = 0;
sin->sin_addr.s_addr = ifa->ifa_local;
break;
case SIOCGIFBRDADDR: /* Get the broadcast address */
ret = 0;
sin->sin_addr.s_addr = ifa->ifa_broadcast;
break;
case SIOCGIFDSTADDR: /* Get the destination address */
ret = 0;
sin->sin_addr.s_addr = ifa->ifa_address;
break;
case SIOCGIFNETMASK: /* Get the netmask for the interface */
ret = 0;
sin->sin_addr.s_addr = ifa->ifa_mask;
break;
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, NULL);
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;
INIT_HLIST_NODE(&ifa->hash);
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);
}
set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
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;
}
int inet_gifconf(struct net_device *dev, char __user *buf, int len, int size)
{
struct in_device *in_dev = __in_dev_get_rtnl(dev);
const struct in_ifaddr *ifa;
struct ifreq ifr;
int done = 0;
if (WARN_ON(size > sizeof(struct ifreq)))
goto out;
if (!in_dev)
goto out;
in_dev_for_each_ifa_rtnl(ifa, in_dev) {
if (!buf) {
done += size;
continue;
}
if (len < size)
break;
memset(&ifr, 0, sizeof(struct ifreq));
strcpy(ifr.ifr_name, ifa->ifa_label);
(*(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 + done, &ifr, size)) {
done = -EFAULT;
break;
}
len -= size;
done += size;
}
out:
return done;
}
static __be32 in_dev_select_addr(const struct in_device *in_dev,
int scope)
{
const struct in_ifaddr *ifa;
in_dev_for_each_ifa_rcu(ifa, in_dev) {
if (READ_ONCE(ifa->ifa_flags) & IFA_F_SECONDARY)
continue;
if (ifa->ifa_scope != RT_SCOPE_LINK &&
ifa->ifa_scope <= scope)
return ifa->ifa_local;
}
return 0;
}
__be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
{
const struct in_ifaddr *ifa;
__be32 addr = 0;
unsigned char localnet_scope = RT_SCOPE_HOST;
struct in_device *in_dev;
struct net *net = dev_net(dev);
int master_idx;
rcu_read_lock();
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
goto no_in_dev;
if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
localnet_scope = RT_SCOPE_LINK;
in_dev_for_each_ifa_rcu(ifa, in_dev) {
if (READ_ONCE(ifa->ifa_flags) & IFA_F_SECONDARY)
continue;
if (min(ifa->ifa_scope, localnet_scope) > scope)
continue;
if (!dst || inet_ifa_match(dst, ifa)) {
addr = ifa->ifa_local;
break;
}
if (!addr)
addr = ifa->ifa_local;
}
if (addr)
goto out_unlock;
no_in_dev:
master_idx = l3mdev_master_ifindex_rcu(dev);
/* For VRFs, the VRF device takes the place of the loopback device,
* with addresses on it being preferred. Note in such cases the
* loopback device will be among the devices that fail the master_idx
* equality check in the loop below.
*/
if (master_idx &&
(dev = dev_get_by_index_rcu(net, master_idx)) &&
(in_dev = __in_dev_get_rcu(dev))) {
addr = in_dev_select_addr(in_dev, scope);
if (addr)
goto out_unlock;
}
/* Not loopback addresses on loopback should be preferred
in this case. It is important that lo is the first interface
in dev_base list.
*/
for_each_netdev_rcu(net, dev) {
if (l3mdev_master_ifindex_rcu(dev) != master_idx)
continue;
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
continue;
addr = in_dev_select_addr(in_dev, scope);
if (addr)
goto out_unlock;
}
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)
{
unsigned char localnet_scope = RT_SCOPE_HOST;
const struct in_ifaddr *ifa;
__be32 addr = 0;
int same = 0;
if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
localnet_scope = RT_SCOPE_LINK;
in_dev_for_each_ifa_rcu(ifa, in_dev) {
unsigned char min_scope = min(ifa->ifa_scope, localnet_scope);
if (!addr &&
(local == ifa->ifa_local || !local) &&
min_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 (min_scope <= scope) {
addr = ifa->ifa_local;
break;
}
/* search for large dst subnet for addr */
same = 0;
}
}
}
return same ? addr : 0;
}
/*
* Confirm that local IP address exists using wildcards:
* - net: netns to check, cannot be NULL
* - in_dev: only on this interface, NULL=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 net *net, struct in_device *in_dev,
__be32 dst, __be32 local, int scope)
{
__be32 addr = 0;
struct net_device *dev;
if (in_dev)
return confirm_addr_indev(in_dev, dst, local, scope);
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;
}
EXPORT_SYMBOL(inet_confirm_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);
int register_inetaddr_validator_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&inetaddr_validator_chain, nb);
}
EXPORT_SYMBOL(register_inetaddr_validator_notifier);
int unregister_inetaddr_validator_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&inetaddr_validator_chain,
nb);
}
EXPORT_SYMBOL(unregister_inetaddr_validator_notifier);
/* 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;
in_dev_for_each_ifa_rtnl(ifa, in_dev) {
char old[IFNAMSIZ], *dot;
memcpy(old, ifa->ifa_label, IFNAMSIZ);
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
if (named++ == 0)
goto skip;
dot = strchr(old, ':');
if (!dot) {
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);
skip:
rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
}
}
static void inetdev_send_gratuitous_arp(struct net_device *dev,
struct in_device *in_dev)
{
const struct in_ifaddr *ifa;
in_dev_for_each_ifa_rtnl(ifa, in_dev) {
arp_send(ARPOP_REQUEST, ETH_P_ARP,
ifa->ifa_local, dev,
ifa->ifa_local, NULL,
dev->dev_addr, NULL);
}
}
/* Called only under RTNL semaphore */
static int inetdev_event(struct notifier_block *this, unsigned long event,
void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct in_device *in_dev = __in_dev_get_rtnl(dev);
ASSERT_RTNL();
if (!in_dev) {
if (event == NETDEV_REGISTER) {
in_dev = inetdev_init(dev);
if (IS_ERR(in_dev))
return notifier_from_errno(PTR_ERR(in_dev));
if (dev->flags & IFF_LOOPBACK) {
IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
}
} else if (event == NETDEV_CHANGEMTU) {
/* Re-enabling IP */
if (inetdev_valid_mtu(dev->mtu))
in_dev = inetdev_init(dev);
}
goto out;
}
switch (event) {
case NETDEV_REGISTER:
pr_debug("%s: bug\n", __func__);
RCU_INIT_POINTER(dev->ip_ptr, NULL);
break;
case NETDEV_UP:
if (!inetdev_valid_mtu(dev->mtu))
break;
if (dev->flags & IFF_LOOPBACK) {
struct in_ifaddr *ifa = inet_alloc_ifa();
if (ifa) {
INIT_HLIST_NODE(&ifa->hash);
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);
set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,
INFINITY_LIFE_TIME);
ipv4_devconf_setall(in_dev);
neigh_parms_data_state_setall(in_dev->arp_parms);
inet_insert_ifa(ifa);
}
}
ip_mc_up(in_dev);
fallthrough;
case NETDEV_CHANGEADDR:
if (!IN_DEV_ARP_NOTIFY(in_dev))
break;
fallthrough;
case NETDEV_NOTIFY_PEERS:
/* Send gratuitous ARP to notify of link change */
inetdev_send_gratuitous_arp(dev, in_dev);
break;
case NETDEV_DOWN:
ip_mc_down(in_dev);
break;
case NETDEV_PRE_TYPE_CHANGE:
ip_mc_unmap(in_dev);
break;
case NETDEV_POST_TYPE_CHANGE:
ip_mc_remap(in_dev);
break;
case NETDEV_CHANGEMTU:
if (inetdev_valid_mtu(dev->mtu))
break;
/* disable IP when MTU is not enough */
fallthrough;
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);
devinet_sysctl_unregister(in_dev);
devinet_sysctl_register(in_dev);
break;
}
out:
return NOTIFY_DONE;
}
static struct notifier_block ip_netdev_notifier = {
.notifier_call = inetdev_event,
};
static size_t inet_nlmsg_size(void)
{
return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
+ nla_total_size(4) /* IFA_ADDRESS */
+ nla_total_size(4) /* IFA_LOCAL */
+ nla_total_size(4) /* IFA_BROADCAST */
+ nla_total_size(IFNAMSIZ) /* IFA_LABEL */
+ nla_total_size(4) /* IFA_FLAGS */
+ nla_total_size(1) /* IFA_PROTO */
+ nla_total_size(4) /* IFA_RT_PRIORITY */
+ nla_total_size(sizeof(struct ifa_cacheinfo)); /* IFA_CACHEINFO */
}
static inline u32 cstamp_delta(unsigned long cstamp)
{
return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
}
static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
unsigned long tstamp, u32 preferred, u32 valid)
{
struct ifa_cacheinfo ci;
ci.cstamp = cstamp_delta(cstamp);
ci.tstamp = cstamp_delta(tstamp);
ci.ifa_prefered = preferred;
ci.ifa_valid = valid;
return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
}
static int inet_fill_ifaddr(struct sk_buff *skb, const struct in_ifaddr *ifa,
struct inet_fill_args *args)
{
struct ifaddrmsg *ifm;
struct nlmsghdr *nlh;
unsigned long tstamp;
u32 preferred, valid;
nlh = nlmsg_put(skb, args->portid, args->seq, args->event, sizeof(*ifm),
args->flags);
if (!nlh)
return -EMSGSIZE;
ifm = nlmsg_data(nlh);
ifm->ifa_family = AF_INET;
ifm->ifa_prefixlen = ifa->ifa_prefixlen;
ifm->ifa_flags = READ_ONCE(ifa->ifa_flags);
ifm->ifa_scope = ifa->ifa_scope;
ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
if (args->netnsid >= 0 &&
nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
goto nla_put_failure;
tstamp = READ_ONCE(ifa->ifa_tstamp);
if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
preferred = READ_ONCE(ifa->ifa_preferred_lft);
valid = READ_ONCE(ifa->ifa_valid_lft);
if (preferred != INFINITY_LIFE_TIME) {
long tval = (jiffies - tstamp) / HZ;
if (preferred > tval)
preferred -= tval;
else
preferred = 0;
if (valid != INFINITY_LIFE_TIME) {
if (valid > tval)
valid -= tval;
else
valid = 0;
}
}
} else {
preferred = INFINITY_LIFE_TIME;
valid = INFINITY_LIFE_TIME;
}
if ((ifa->ifa_address &&
nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) ||
(ifa->ifa_local &&
nla_put_in_addr(skb, IFA_LOCAL, ifa->ifa_local)) ||
(ifa->ifa_broadcast &&
nla_put_in_addr(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
(ifa->ifa_label[0] &&
nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
(ifa->ifa_proto &&
nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto)) ||
nla_put_u32(skb, IFA_FLAGS, ifm->ifa_flags) ||
(ifa->ifa_rt_priority &&
nla_put_u32(skb, IFA_RT_PRIORITY, ifa->ifa_rt_priority)) ||
put_cacheinfo(skb, READ_ONCE(ifa->ifa_cstamp), tstamp,
preferred, valid))
goto nla_put_failure;
nlmsg_end(skb, nlh);
return 0;
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static int inet_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
struct inet_fill_args *fillargs,
struct net **tgt_net, struct sock *sk,
struct netlink_callback *cb)
{
struct netlink_ext_ack *extack = cb->extack;
struct nlattr *tb[IFA_MAX+1];
struct ifaddrmsg *ifm;
int err, i;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid header for address dump request");
return -EINVAL;
}
ifm = nlmsg_data(nlh);
if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for address dump request");
return -EINVAL;
}
fillargs->ifindex = ifm->ifa_index;
if (fillargs->ifindex) {
cb->answer_flags |= NLM_F_DUMP_FILTERED;
fillargs->flags |= NLM_F_DUMP_FILTERED;
}
err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
ifa_ipv4_policy, extack);
if (err < 0)
return err;
for (i = 0; i <= IFA_MAX; ++i) {
if (!tb[i])
continue;
if (i == IFA_TARGET_NETNSID) {
struct net *net;
fillargs->netnsid = nla_get_s32(tb[i]);
net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
if (IS_ERR(net)) {
fillargs->netnsid = -1;
NL_SET_ERR_MSG(extack, "ipv4: Invalid target network namespace id");
return PTR_ERR(net);
}
*tgt_net = net;
} else {
NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in dump request");
return -EINVAL;
}
}
return 0;
}
static int in_dev_dump_addr(struct in_device *in_dev, struct sk_buff *skb,
struct netlink_callback *cb, int *s_ip_idx,
struct inet_fill_args *fillargs)
{
struct in_ifaddr *ifa;
int ip_idx = 0;
int err;
in_dev_for_each_ifa_rcu(ifa, in_dev) {
if (ip_idx < *s_ip_idx) {
ip_idx++;
continue;
}
err = inet_fill_ifaddr(skb, ifa, fillargs);
if (err < 0)
goto done;
nl_dump_check_consistent(cb, nlmsg_hdr(skb));
ip_idx++;
}
err = 0;
ip_idx = 0;
done:
*s_ip_idx = ip_idx;
return err;
}
/* Combine dev_addr_genid and dev_base_seq to detect changes.
*/
static u32 inet_base_seq(const struct net *net)
{
u32 res = atomic_read(&net->ipv4.dev_addr_genid) +
READ_ONCE(net->dev_base_seq);
/* Must not return 0 (see nl_dump_check_consistent()).
* Chose a value far away from 0.
*/
if (!res)
res = 0x80000000;
return res;
}
static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
{
const struct nlmsghdr *nlh = cb->nlh;
struct inet_fill_args fillargs = {
.portid = NETLINK_CB(cb->skb).portid,
.seq = nlh->nlmsg_seq,
.event = RTM_NEWADDR,
.flags = NLM_F_MULTI,
.netnsid = -1,
};
struct net *net = sock_net(skb->sk);
struct net *tgt_net = net;
struct {
unsigned long ifindex;
int ip_idx;
} *ctx = (void *)cb->ctx;
struct in_device *in_dev;
struct net_device *dev;
int err = 0;
rcu_read_lock();
if (cb->strict_check) {
err = inet_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
skb->sk, cb);
if (err < 0)
goto done;
if (fillargs.ifindex) {
err = -ENODEV;
dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
if (!dev)
goto done;
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
goto done;
err = in_dev_dump_addr(in_dev, skb, cb, &ctx->ip_idx,
&fillargs);
goto done;
}
}
cb->seq = inet_base_seq(tgt_net);
for_each_netdev_dump(net, dev, ctx->ifindex) {
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
continue;
err = in_dev_dump_addr(in_dev, skb, cb, &ctx->ip_idx,
&fillargs);
if (err < 0)
goto done;
}
done:
if (fillargs.netnsid >= 0)
put_net(tgt_net);
rcu_read_unlock();
return err;
}
static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
u32 portid)
{
struct inet_fill_args fillargs = {
.portid = portid,
.seq = nlh ? nlh->nlmsg_seq : 0,
.event = event,
.flags = 0,
.netnsid = -1,
};
struct sk_buff *skb;
int err = -ENOBUFS;
struct net *net;
net = dev_net(ifa->ifa_dev->dev);
skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
if (!skb)
goto errout;
err = inet_fill_ifaddr(skb, ifa, &fillargs);
if (err < 0) {
/* -EMSGSIZE implies BUG in inet_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
return;
errout:
if (err < 0)
rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
}
static size_t inet_get_link_af_size(const struct net_device *dev,
u32 ext_filter_mask)
{
struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
if (!in_dev)
return 0;
return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
}
static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
u32 ext_filter_mask)
{
struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
struct nlattr *nla;
int i;
if (!in_dev)
return -ENODATA;
nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
if (!nla)
return -EMSGSIZE;
for (i = 0; i < IPV4_DEVCONF_MAX; i++)
((u32 *) nla_data(nla))[i] = READ_ONCE(in_dev->cnf.data[i]);
return 0;
}
static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
[IFLA_INET_CONF] = { .type = NLA_NESTED },
};
static int inet_validate_link_af(const struct net_device *dev,
const struct nlattr *nla,
struct netlink_ext_ack *extack)
{
struct nlattr *a, *tb[IFLA_INET_MAX+1];
int err, rem;
if (dev && !__in_dev_get_rtnl(dev))
return -EAFNOSUPPORT;
err = nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla,
inet_af_policy, extack);
if (err < 0)
return err;
if (tb[IFLA_INET_CONF]) {
nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
int cfgid = nla_type(a);
if (nla_len(a) < 4)
return -EINVAL;
if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
return -EINVAL;
}
}
return 0;
}
static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla,
struct netlink_ext_ack *extack)
{
struct in_device *in_dev = __in_dev_get_rtnl(dev);
struct nlattr *a, *tb[IFLA_INET_MAX+1];
int rem;
if (!in_dev)
return -EAFNOSUPPORT;
if (nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla, NULL, NULL) < 0)
return -EINVAL;
if (tb[IFLA_INET_CONF]) {
nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
}
return 0;
}
static int inet_netconf_msgsize_devconf(int type)
{
int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
+ nla_total_size(4); /* NETCONFA_IFINDEX */
bool all = false;
if (type == NETCONFA_ALL)
all = true;
if (all || type == NETCONFA_FORWARDING)
size += nla_total_size(4);
if (all || type == NETCONFA_RP_FILTER)
size += nla_total_size(4);
if (all || type == NETCONFA_MC_FORWARDING)
size += nla_total_size(4);
if (all || type == NETCONFA_BC_FORWARDING)
size += nla_total_size(4);
if (all || type == NETCONFA_PROXY_NEIGH)
size += nla_total_size(4);
if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
size += nla_total_size(4);
return size;
}
static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
const struct ipv4_devconf *devconf,
u32 portid, u32 seq, int event,
unsigned int flags, int type)
{
struct nlmsghdr *nlh;
struct netconfmsg *ncm;
bool all = false;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
flags);
if (!nlh)
return -EMSGSIZE;
if (type == NETCONFA_ALL)
all = true;
ncm = nlmsg_data(nlh);
ncm->ncm_family = AF_INET;
if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
goto nla_put_failure;
if (!devconf)
goto out;
if ((all || type == NETCONFA_FORWARDING) &&
nla_put_s32(skb, NETCONFA_FORWARDING,
IPV4_DEVCONF_RO(*devconf, FORWARDING)) < 0)
goto nla_put_failure;
if ((all || type == NETCONFA_RP_FILTER) &&
nla_put_s32(skb, NETCONFA_RP_FILTER,
IPV4_DEVCONF_RO(*devconf, RP_FILTER)) < 0)
goto nla_put_failure;
if ((all || type == NETCONFA_MC_FORWARDING) &&
nla_put_s32(skb, NETCONFA_MC_FORWARDING,
IPV4_DEVCONF_RO(*devconf, MC_FORWARDING)) < 0)
goto nla_put_failure;
if ((all || type == NETCONFA_BC_FORWARDING) &&
nla_put_s32(skb, NETCONFA_BC_FORWARDING,
IPV4_DEVCONF_RO(*devconf, BC_FORWARDING)) < 0)
goto nla_put_failure;
if ((all || type == NETCONFA_PROXY_NEIGH) &&
nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
IPV4_DEVCONF_RO(*devconf, PROXY_ARP)) < 0)
goto nla_put_failure;
if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
IPV4_DEVCONF_RO(*devconf,
IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
goto nla_put_failure;
out:
nlmsg_end(skb, nlh);
return 0;
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
void inet_netconf_notify_devconf(struct net *net, int event, int type,
int ifindex, struct ipv4_devconf *devconf)
{
struct sk_buff *skb;
int err = -ENOBUFS;
skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_KERNEL);
if (!skb)
goto errout;
err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
event, 0, type);
if (err < 0) {
/* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_KERNEL);
return;
errout:
if (err < 0)
rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err);
}
static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
[NETCONFA_IFINDEX] = { .len = sizeof(int) },
[NETCONFA_FORWARDING] = { .len = sizeof(int) },
[NETCONFA_RP_FILTER] = { .len = sizeof(int) },
[NETCONFA_PROXY_NEIGH] = { .len = sizeof(int) },
[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN] = { .len = sizeof(int) },
};
static int inet_netconf_valid_get_req(struct sk_buff *skb,
const struct nlmsghdr *nlh,
struct nlattr **tb,
struct netlink_ext_ack *extack)
{
int i, err;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf get request");
return -EINVAL;
}
if (!netlink_strict_get_check(skb))
return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
tb, NETCONFA_MAX,
devconf_ipv4_policy, extack);
err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
tb, NETCONFA_MAX,
devconf_ipv4_policy, extack);
if (err)
return err;
for (i = 0; i <= NETCONFA_MAX; i++) {
if (!tb[i])
continue;
switch (i) {
case NETCONFA_IFINDEX:
break;
default:
NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in netconf get request");
return -EINVAL;
}
}
return 0;
}
static int inet_netconf_get_devconf(struct sk_buff *in_skb,
struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(in_skb->sk);
struct nlattr *tb[NETCONFA_MAX + 1];
const struct ipv4_devconf *devconf;
struct in_device *in_dev = NULL;
struct net_device *dev = NULL;
struct sk_buff *skb;
int ifindex;
int err;
err = inet_netconf_valid_get_req(in_skb, nlh, tb, extack);
if (err)
return err;
if (!tb[NETCONFA_IFINDEX])
return -EINVAL;
ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
switch (ifindex) {
case NETCONFA_IFINDEX_ALL:
devconf = net->ipv4.devconf_all;
break;
case NETCONFA_IFINDEX_DEFAULT:
devconf = net->ipv4.devconf_dflt;
break;
default:
err = -ENODEV;
dev = dev_get_by_index(net, ifindex);
if (dev)
in_dev = in_dev_get(dev);
if (!in_dev)
goto errout;
devconf = &in_dev->cnf;
break;
}
err = -ENOBUFS;
skb = nlmsg_new(inet_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
if (!skb)
goto errout;
err = inet_netconf_fill_devconf(skb, ifindex, devconf,
NETLINK_CB(in_skb).portid,
nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
NETCONFA_ALL);
if (err < 0) {
/* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
errout:
if (in_dev)
in_dev_put(in_dev);
dev_put(dev);
return err;
}
static int inet_netconf_dump_devconf(struct sk_buff *skb,
struct netlink_callback *cb)
{
const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
struct {
unsigned long ifindex;
unsigned int all_default;
} *ctx = (void *)cb->ctx;
const struct in_device *in_dev;
struct net_device *dev;
int err = 0;
if (cb->strict_check) {
struct netlink_ext_ack *extack = cb->extack;
struct netconfmsg *ncm;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf dump request");
return -EINVAL;
}
if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
NL_SET_ERR_MSG(extack, "ipv4: Invalid data after header in netconf dump request");
return -EINVAL;
}
}
rcu_read_lock();
for_each_netdev_dump(net, dev, ctx->ifindex) {
in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
continue;
err = inet_netconf_fill_devconf(skb, dev->ifindex,
&in_dev->cnf,
NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq,
RTM_NEWNETCONF, NLM_F_MULTI,
NETCONFA_ALL);
if (err < 0)
goto done;
}
if (ctx->all_default == 0) {
err = inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
net->ipv4.devconf_all,
NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq,
RTM_NEWNETCONF, NLM_F_MULTI,
NETCONFA_ALL);
if (err < 0)
goto done;
ctx->all_default++;
}
if (ctx->all_default == 1) {
err = inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
net->ipv4.devconf_dflt,
NETLINK_CB(cb->skb).portid,
nlh->nlmsg_seq,
RTM_NEWNETCONF, NLM_F_MULTI,
NETCONFA_ALL);
if (err < 0)
goto done;
ctx->all_default++;
}
done:
rcu_read_unlock();
return err;
}
#ifdef CONFIG_SYSCTL
static void devinet_copy_dflt_conf(struct net *net, int i)
{
struct net_device *dev;
rcu_read_lock();
for_each_netdev_rcu(net, dev) {
struct in_device *in_dev;
in_dev = __in_dev_get_rcu(dev);
if (in_dev && !test_bit(i, in_dev->cnf.state))
in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
}
rcu_read_unlock();
}
/* called with RTNL locked */
static void inet_forward_change(struct net *net)
{
struct net_device *dev;
int on = IPV4_DEVCONF_ALL(net, FORWARDING);
IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_FORWARDING,
NETCONFA_IFINDEX_ALL,
net->ipv4.devconf_all);
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_FORWARDING,
NETCONFA_IFINDEX_DEFAULT,
net->ipv4.devconf_dflt);
for_each_netdev(net, dev) {
struct in_device *in_dev;
if (on)
dev_disable_lro(dev);
in_dev = __in_dev_get_rtnl(dev);
if (in_dev) {
IN_DEV_CONF_SET(in_dev, FORWARDING, on);
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_FORWARDING,
dev->ifindex, &in_dev->cnf);
}
}
}
static int devinet_conf_ifindex(struct net *net, struct ipv4_devconf *cnf)
{
if (cnf == net->ipv4.devconf_dflt)
return NETCONFA_IFINDEX_DEFAULT;
else if (cnf == net->ipv4.devconf_all)
return NETCONFA_IFINDEX_ALL;
else {
struct in_device *idev
= container_of(cnf, struct in_device, cnf);
return idev->dev->ifindex;
}
}
static int devinet_conf_proc(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int old_value = *(int *)ctl->data;
int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
int new_value = *(int *)ctl->data;
if (write) {
struct ipv4_devconf *cnf = ctl->extra1;
struct net *net = ctl->extra2;
int i = (int *)ctl->data - cnf->data;
int ifindex;
set_bit(i, cnf->state);
if (cnf == net->ipv4.devconf_dflt)
devinet_copy_dflt_conf(net, i);
if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 ||
i == IPV4_DEVCONF_ROUTE_LOCALNET - 1)
if ((new_value == 0) && (old_value != 0))
rt_cache_flush(net);
if (i == IPV4_DEVCONF_BC_FORWARDING - 1 &&
new_value != old_value)
rt_cache_flush(net);
if (i == IPV4_DEVCONF_RP_FILTER - 1 &&
new_value != old_value) {
ifindex = devinet_conf_ifindex(net, cnf);
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_RP_FILTER,
ifindex, cnf);
}
if (i == IPV4_DEVCONF_PROXY_ARP - 1 &&
new_value != old_value) {
ifindex = devinet_conf_ifindex(net, cnf);
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_PROXY_NEIGH,
ifindex, cnf);
}
if (i == IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN - 1 &&
new_value != old_value) {
ifindex = devinet_conf_ifindex(net, cnf);
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
ifindex, cnf);
}
}
return ret;
}
static int devinet_sysctl_forward(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int *valp = ctl->data;
int val = *valp;
loff_t pos = *ppos;
struct net *net = ctl->extra2;
int ret;
if (write && !ns_capable(net->user_ns, CAP_NET_ADMIN))
return -EPERM;
ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
if (write && *valp != val) {
if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
if (!rtnl_trylock()) {
/* Restore the original values before restarting */
*valp = val;
*ppos = pos;
return restart_syscall();
}
if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
inet_forward_change(net);
} else {
struct ipv4_devconf *cnf = ctl->extra1;
struct in_device *idev =
container_of(cnf, struct in_device, cnf);
if (*valp)
dev_disable_lro(idev->dev);
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_FORWARDING,
idev->dev->ifindex,
cnf);
}
rtnl_unlock();
rt_cache_flush(net);
} else
inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
NETCONFA_FORWARDING,
NETCONFA_IFINDEX_DEFAULT,
net->ipv4.devconf_dflt);
}
return ret;
}
static int ipv4_doint_and_flush(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
int *valp = ctl->data;
int val = *valp;
int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
struct net *net = ctl->extra2;
if (write && *valp != val)
rt_cache_flush(net);
return ret;
}
#define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
{ \
.procname = name, \
.data = ipv4_devconf.data + \
IPV4_DEVCONF_ ## attr - 1, \
.maxlen = sizeof(int), \
.mode = mval, \
.proc_handler = proc, \
.extra1 = &ipv4_devconf, \
}
#define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
#define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
#define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
#define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
static struct devinet_sysctl_table {
struct ctl_table_header *sysctl_header;
struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
} devinet_sysctl = {
.devinet_vars = {
DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
devinet_sysctl_forward),
DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
DEVINET_SYSCTL_RW_ENTRY(BC_FORWARDING, "bc_forwarding"),
DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
"accept_source_route"),
DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
DEVINET_SYSCTL_RW_ENTRY(ARP_EVICT_NOCARRIER,
"arp_evict_nocarrier"),
DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION,
"force_igmp_version"),
DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL,
"igmpv2_unsolicited_report_interval"),
DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL,
"igmpv3_unsolicited_report_interval"),
DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN,
"ignore_routes_with_linkdown"),
DEVINET_SYSCTL_RW_ENTRY(DROP_GRATUITOUS_ARP,
"drop_gratuitous_arp"),
DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
"promote_secondaries"),
DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET,
"route_localnet"),
DEVINET_SYSCTL_FLUSHING_ENTRY(DROP_UNICAST_IN_L2_MULTICAST,
"drop_unicast_in_l2_multicast"),
},
};
static int __devinet_sysctl_register(struct net *net, char *dev_name,
int ifindex, struct ipv4_devconf *p)
{
int i;
struct devinet_sysctl_table *t;
char path[sizeof("net/ipv4/conf/") + IFNAMSIZ];
t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL_ACCOUNT);
if (!t)
goto out;
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].extra1 = p;
t->devinet_vars[i].extra2 = net;
}
snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name);
t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars);
if (!t->sysctl_header)
goto free;
p->sysctl = t;
inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
ifindex, p);
return 0;
free:
kfree(t);
out:
return -ENOMEM;
}
static void __devinet_sysctl_unregister(struct net *net,
struct ipv4_devconf *cnf, int ifindex)
{
struct devinet_sysctl_table *t = cnf->sysctl;
if (t) {
cnf->sysctl = NULL;
unregister_net_sysctl_table(t->sysctl_header);
kfree(t);
}
inet_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
}
static int devinet_sysctl_register(struct in_device *idev)
{
int err;
if (!sysctl_dev_name_is_allowed(idev->dev->name))
return -EINVAL;
err = neigh_sysctl_register(idev->dev, idev->arp_parms, NULL);
if (err)
return err;
err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
idev->dev->ifindex, &idev->cnf);
if (err)
neigh_sysctl_unregister(idev->arp_parms);
return err;
}
static void devinet_sysctl_unregister(struct in_device *idev)
{
struct net *net = dev_net(idev->dev);
__devinet_sysctl_unregister(net, &idev->cnf, idev->dev->ifindex);
neigh_sysctl_unregister(idev->arp_parms);
}
static struct ctl_table ctl_forward_entry[] = {
{
.procname = "ip_forward",
.data = &ipv4_devconf.data[
IPV4_DEVCONF_FORWARDING - 1],
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = devinet_sysctl_forward,
.extra1 = &ipv4_devconf,
.extra2 = &init_net,
},
{ },
};
#endif
static __net_init int devinet_init_net(struct net *net)
{
int err;
struct ipv4_devconf *all, *dflt;
#ifdef CONFIG_SYSCTL
struct ctl_table *tbl;
struct ctl_table_header *forw_hdr;
#endif
err = -ENOMEM;
all = kmemdup(&ipv4_devconf, sizeof(ipv4_devconf), GFP_KERNEL);
if (!all)
goto err_alloc_all;
dflt = kmemdup(&ipv4_devconf_dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
if (!dflt)
goto err_alloc_dflt;
#ifdef CONFIG_SYSCTL
tbl = kmemdup(ctl_forward_entry, sizeof(ctl_forward_entry), GFP_KERNEL);
if (!tbl)
goto err_alloc_ctl;
tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
tbl[0].extra1 = all;
tbl[0].extra2 = net;
#endif
if (!net_eq(net, &init_net)) {
switch (net_inherit_devconf()) {
case 3:
/* copy from the current netns */
memcpy(all, current->nsproxy->net_ns->ipv4.devconf_all,
sizeof(ipv4_devconf));
memcpy(dflt,
current->nsproxy->net_ns->ipv4.devconf_dflt,
sizeof(ipv4_devconf_dflt));
break;
case 0:
case 1:
/* copy from init_net */
memcpy(all, init_net.ipv4.devconf_all,
sizeof(ipv4_devconf));
memcpy(dflt, init_net.ipv4.devconf_dflt,
sizeof(ipv4_devconf_dflt));
break;
case 2:
/* use compiled values */
break;
}
}
#ifdef CONFIG_SYSCTL
err = __devinet_sysctl_register(net, "all", NETCONFA_IFINDEX_ALL, all);
if (err < 0)
goto err_reg_all;
err = __devinet_sysctl_register(net, "default",
NETCONFA_IFINDEX_DEFAULT, dflt);
if (err < 0)
goto err_reg_dflt;
err = -ENOMEM;
forw_hdr = register_net_sysctl_sz(net, "net/ipv4", tbl,
ARRAY_SIZE(ctl_forward_entry));
if (!forw_hdr)
goto err_reg_ctl;
net->ipv4.forw_hdr = forw_hdr;
#endif
net->ipv4.devconf_all = all;
net->ipv4.devconf_dflt = dflt;
return 0;
#ifdef CONFIG_SYSCTL
err_reg_ctl:
__devinet_sysctl_unregister(net, dflt, NETCONFA_IFINDEX_DEFAULT);
err_reg_dflt:
__devinet_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
err_reg_all:
kfree(tbl);
err_alloc_ctl:
#endif
kfree(dflt);
err_alloc_dflt:
kfree(all);
err_alloc_all:
return err;
}
static __net_exit void devinet_exit_net(struct net *net)
{
#ifdef CONFIG_SYSCTL
struct ctl_table *tbl;
tbl = net->ipv4.forw_hdr->ctl_table_arg;
unregister_net_sysctl_table(net->ipv4.forw_hdr);
__devinet_sysctl_unregister(net, net->ipv4.devconf_dflt,
NETCONFA_IFINDEX_DEFAULT);
__devinet_sysctl_unregister(net, net->ipv4.devconf_all,
NETCONFA_IFINDEX_ALL);
kfree(tbl);
#endif
kfree(net->ipv4.devconf_dflt);
kfree(net->ipv4.devconf_all);
}
static __net_initdata struct pernet_operations devinet_ops = {
.init = devinet_init_net,
.exit = devinet_exit_net,
};
static struct rtnl_af_ops inet_af_ops __read_mostly = {
.family = AF_INET,
.fill_link_af = inet_fill_link_af,
.get_link_af_size = inet_get_link_af_size,
.validate_link_af = inet_validate_link_af,
.set_link_af = inet_set_link_af,
};
void __init devinet_init(void)
{
int i;
for (i = 0; i < IN4_ADDR_HSIZE; i++)
INIT_HLIST_HEAD(&inet_addr_lst[i]);
register_pernet_subsys(&devinet_ops);
register_netdevice_notifier(&ip_netdev_notifier);
queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
rtnl_af_register(&inet_af_ops);
rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, 0);
rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, 0);
rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr,
RTNL_FLAG_DUMP_UNLOCKED);
rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
inet_netconf_dump_devconf,
RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED);
}