android_kernel_xiaomi_sm8350/net/core/rtnetlink.c
Pablo Neira Ayuso 1ce85fe402 netlink: change nlmsg_notify() return value logic
This patch changes the return value of nlmsg_notify() as follows:

If NETLINK_BROADCAST_ERROR is set by any of the listeners and
an error in the delivery happened, return the broadcast error;
else if there are no listeners apart from the socket that
requested a change with the echo flag, return the result of the
unicast notification. Thus, with this patch, the unicast
notification is handled in the same way of a broadcast listener
that has set the NETLINK_BROADCAST_ERROR socket flag.

This patch is useful in case that the caller of nlmsg_notify()
wants to know the result of the delivery of a netlink notification
(including the broadcast delivery) and take any action in case
that the delivery failed. For example, ctnetlink can drop packets
if the event delivery failed to provide reliable logging and
state-synchronization at the cost of dropping packets.

This patch also modifies the rtnetlink code to ignore the return
value of rtnl_notify() in all callers. The function rtnl_notify()
(before this patch) returned the error of the unicast notification
which makes rtnl_set_sk_err() reports errors to all listeners. This
is not of any help since the origin of the change (the socket that
requested the echoing) notices the ENOBUFS error if the notification
fails and should resync itself.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-24 23:18:28 -08:00

1432 lines
34 KiB
C

/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Routing netlink socket interface: protocol independent part.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* 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.
*
* Fixes:
* Vitaly E. Lavrov RTA_OK arithmetics was wrong.
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/capability.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/security.h>
#include <linux/mutex.h>
#include <linux/if_addr.h>
#include <linux/nsproxy.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/string.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/arp.h>
#include <net/route.h>
#include <net/udp.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
#include <net/fib_rules.h>
#include <net/rtnetlink.h>
struct rtnl_link
{
rtnl_doit_func doit;
rtnl_dumpit_func dumpit;
};
static DEFINE_MUTEX(rtnl_mutex);
void rtnl_lock(void)
{
mutex_lock(&rtnl_mutex);
}
void __rtnl_unlock(void)
{
mutex_unlock(&rtnl_mutex);
}
void rtnl_unlock(void)
{
/* This fellow will unlock it for us. */
netdev_run_todo();
}
int rtnl_trylock(void)
{
return mutex_trylock(&rtnl_mutex);
}
int rtnl_is_locked(void)
{
return mutex_is_locked(&rtnl_mutex);
}
static struct rtnl_link *rtnl_msg_handlers[NPROTO];
static inline int rtm_msgindex(int msgtype)
{
int msgindex = msgtype - RTM_BASE;
/*
* msgindex < 0 implies someone tried to register a netlink
* control code. msgindex >= RTM_NR_MSGTYPES may indicate that
* the message type has not been added to linux/rtnetlink.h
*/
BUG_ON(msgindex < 0 || msgindex >= RTM_NR_MSGTYPES);
return msgindex;
}
static rtnl_doit_func rtnl_get_doit(int protocol, int msgindex)
{
struct rtnl_link *tab;
tab = rtnl_msg_handlers[protocol];
if (tab == NULL || tab[msgindex].doit == NULL)
tab = rtnl_msg_handlers[PF_UNSPEC];
return tab ? tab[msgindex].doit : NULL;
}
static rtnl_dumpit_func rtnl_get_dumpit(int protocol, int msgindex)
{
struct rtnl_link *tab;
tab = rtnl_msg_handlers[protocol];
if (tab == NULL || tab[msgindex].dumpit == NULL)
tab = rtnl_msg_handlers[PF_UNSPEC];
return tab ? tab[msgindex].dumpit : NULL;
}
/**
* __rtnl_register - Register a rtnetlink message type
* @protocol: Protocol family or PF_UNSPEC
* @msgtype: rtnetlink message type
* @doit: Function pointer called for each request message
* @dumpit: Function pointer called for each dump request (NLM_F_DUMP) message
*
* Registers the specified function pointers (at least one of them has
* to be non-NULL) to be called whenever a request message for the
* specified protocol family and message type is received.
*
* The special protocol family PF_UNSPEC may be used to define fallback
* function pointers for the case when no entry for the specific protocol
* family exists.
*
* Returns 0 on success or a negative error code.
*/
int __rtnl_register(int protocol, int msgtype,
rtnl_doit_func doit, rtnl_dumpit_func dumpit)
{
struct rtnl_link *tab;
int msgindex;
BUG_ON(protocol < 0 || protocol >= NPROTO);
msgindex = rtm_msgindex(msgtype);
tab = rtnl_msg_handlers[protocol];
if (tab == NULL) {
tab = kcalloc(RTM_NR_MSGTYPES, sizeof(*tab), GFP_KERNEL);
if (tab == NULL)
return -ENOBUFS;
rtnl_msg_handlers[protocol] = tab;
}
if (doit)
tab[msgindex].doit = doit;
if (dumpit)
tab[msgindex].dumpit = dumpit;
return 0;
}
EXPORT_SYMBOL_GPL(__rtnl_register);
/**
* rtnl_register - Register a rtnetlink message type
*
* Identical to __rtnl_register() but panics on failure. This is useful
* as failure of this function is very unlikely, it can only happen due
* to lack of memory when allocating the chain to store all message
* handlers for a protocol. Meant for use in init functions where lack
* of memory implies no sense in continueing.
*/
void rtnl_register(int protocol, int msgtype,
rtnl_doit_func doit, rtnl_dumpit_func dumpit)
{
if (__rtnl_register(protocol, msgtype, doit, dumpit) < 0)
panic("Unable to register rtnetlink message handler, "
"protocol = %d, message type = %d\n",
protocol, msgtype);
}
EXPORT_SYMBOL_GPL(rtnl_register);
/**
* rtnl_unregister - Unregister a rtnetlink message type
* @protocol: Protocol family or PF_UNSPEC
* @msgtype: rtnetlink message type
*
* Returns 0 on success or a negative error code.
*/
int rtnl_unregister(int protocol, int msgtype)
{
int msgindex;
BUG_ON(protocol < 0 || protocol >= NPROTO);
msgindex = rtm_msgindex(msgtype);
if (rtnl_msg_handlers[protocol] == NULL)
return -ENOENT;
rtnl_msg_handlers[protocol][msgindex].doit = NULL;
rtnl_msg_handlers[protocol][msgindex].dumpit = NULL;
return 0;
}
EXPORT_SYMBOL_GPL(rtnl_unregister);
/**
* rtnl_unregister_all - Unregister all rtnetlink message type of a protocol
* @protocol : Protocol family or PF_UNSPEC
*
* Identical to calling rtnl_unregster() for all registered message types
* of a certain protocol family.
*/
void rtnl_unregister_all(int protocol)
{
BUG_ON(protocol < 0 || protocol >= NPROTO);
kfree(rtnl_msg_handlers[protocol]);
rtnl_msg_handlers[protocol] = NULL;
}
EXPORT_SYMBOL_GPL(rtnl_unregister_all);
static LIST_HEAD(link_ops);
/**
* __rtnl_link_register - Register rtnl_link_ops with rtnetlink.
* @ops: struct rtnl_link_ops * to register
*
* The caller must hold the rtnl_mutex. This function should be used
* by drivers that create devices during module initialization. It
* must be called before registering the devices.
*
* Returns 0 on success or a negative error code.
*/
int __rtnl_link_register(struct rtnl_link_ops *ops)
{
if (!ops->dellink)
ops->dellink = unregister_netdevice;
list_add_tail(&ops->list, &link_ops);
return 0;
}
EXPORT_SYMBOL_GPL(__rtnl_link_register);
/**
* rtnl_link_register - Register rtnl_link_ops with rtnetlink.
* @ops: struct rtnl_link_ops * to register
*
* Returns 0 on success or a negative error code.
*/
int rtnl_link_register(struct rtnl_link_ops *ops)
{
int err;
rtnl_lock();
err = __rtnl_link_register(ops);
rtnl_unlock();
return err;
}
EXPORT_SYMBOL_GPL(rtnl_link_register);
static void __rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
{
struct net_device *dev;
restart:
for_each_netdev(net, dev) {
if (dev->rtnl_link_ops == ops) {
ops->dellink(dev);
goto restart;
}
}
}
void rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
{
rtnl_lock();
__rtnl_kill_links(net, ops);
rtnl_unlock();
}
EXPORT_SYMBOL_GPL(rtnl_kill_links);
/**
* __rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
* @ops: struct rtnl_link_ops * to unregister
*
* The caller must hold the rtnl_mutex.
*/
void __rtnl_link_unregister(struct rtnl_link_ops *ops)
{
struct net *net;
for_each_net(net) {
__rtnl_kill_links(net, ops);
}
list_del(&ops->list);
}
EXPORT_SYMBOL_GPL(__rtnl_link_unregister);
/**
* rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink.
* @ops: struct rtnl_link_ops * to unregister
*/
void rtnl_link_unregister(struct rtnl_link_ops *ops)
{
rtnl_lock();
__rtnl_link_unregister(ops);
rtnl_unlock();
}
EXPORT_SYMBOL_GPL(rtnl_link_unregister);
static const struct rtnl_link_ops *rtnl_link_ops_get(const char *kind)
{
const struct rtnl_link_ops *ops;
list_for_each_entry(ops, &link_ops, list) {
if (!strcmp(ops->kind, kind))
return ops;
}
return NULL;
}
static size_t rtnl_link_get_size(const struct net_device *dev)
{
const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
size_t size;
if (!ops)
return 0;
size = nlmsg_total_size(sizeof(struct nlattr)) + /* IFLA_LINKINFO */
nlmsg_total_size(strlen(ops->kind) + 1); /* IFLA_INFO_KIND */
if (ops->get_size)
/* IFLA_INFO_DATA + nested data */
size += nlmsg_total_size(sizeof(struct nlattr)) +
ops->get_size(dev);
if (ops->get_xstats_size)
size += ops->get_xstats_size(dev); /* IFLA_INFO_XSTATS */
return size;
}
static int rtnl_link_fill(struct sk_buff *skb, const struct net_device *dev)
{
const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
struct nlattr *linkinfo, *data;
int err = -EMSGSIZE;
linkinfo = nla_nest_start(skb, IFLA_LINKINFO);
if (linkinfo == NULL)
goto out;
if (nla_put_string(skb, IFLA_INFO_KIND, ops->kind) < 0)
goto err_cancel_link;
if (ops->fill_xstats) {
err = ops->fill_xstats(skb, dev);
if (err < 0)
goto err_cancel_link;
}
if (ops->fill_info) {
data = nla_nest_start(skb, IFLA_INFO_DATA);
if (data == NULL)
goto err_cancel_link;
err = ops->fill_info(skb, dev);
if (err < 0)
goto err_cancel_data;
nla_nest_end(skb, data);
}
nla_nest_end(skb, linkinfo);
return 0;
err_cancel_data:
nla_nest_cancel(skb, data);
err_cancel_link:
nla_nest_cancel(skb, linkinfo);
out:
return err;
}
static const int rtm_min[RTM_NR_FAMILIES] =
{
[RTM_FAM(RTM_NEWLINK)] = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
[RTM_FAM(RTM_NEWADDR)] = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
[RTM_FAM(RTM_NEWROUTE)] = NLMSG_LENGTH(sizeof(struct rtmsg)),
[RTM_FAM(RTM_NEWRULE)] = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
[RTM_FAM(RTM_NEWQDISC)] = NLMSG_LENGTH(sizeof(struct tcmsg)),
[RTM_FAM(RTM_NEWTCLASS)] = NLMSG_LENGTH(sizeof(struct tcmsg)),
[RTM_FAM(RTM_NEWTFILTER)] = NLMSG_LENGTH(sizeof(struct tcmsg)),
[RTM_FAM(RTM_NEWACTION)] = NLMSG_LENGTH(sizeof(struct tcamsg)),
[RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
[RTM_FAM(RTM_GETANYCAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
};
static const int rta_max[RTM_NR_FAMILIES] =
{
[RTM_FAM(RTM_NEWLINK)] = IFLA_MAX,
[RTM_FAM(RTM_NEWADDR)] = IFA_MAX,
[RTM_FAM(RTM_NEWROUTE)] = RTA_MAX,
[RTM_FAM(RTM_NEWRULE)] = FRA_MAX,
[RTM_FAM(RTM_NEWQDISC)] = TCA_MAX,
[RTM_FAM(RTM_NEWTCLASS)] = TCA_MAX,
[RTM_FAM(RTM_NEWTFILTER)] = TCA_MAX,
[RTM_FAM(RTM_NEWACTION)] = TCAA_MAX,
};
void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
{
struct rtattr *rta;
int size = RTA_LENGTH(attrlen);
rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
rta->rta_type = attrtype;
rta->rta_len = size;
memcpy(RTA_DATA(rta), data, attrlen);
memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
}
int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned group, int echo)
{
struct sock *rtnl = net->rtnl;
int err = 0;
NETLINK_CB(skb).dst_group = group;
if (echo)
atomic_inc(&skb->users);
netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
if (echo)
err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
return err;
}
int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid)
{
struct sock *rtnl = net->rtnl;
return nlmsg_unicast(rtnl, skb, pid);
}
void rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid, u32 group,
struct nlmsghdr *nlh, gfp_t flags)
{
struct sock *rtnl = net->rtnl;
int report = 0;
if (nlh)
report = nlmsg_report(nlh);
nlmsg_notify(rtnl, skb, pid, group, report, flags);
}
void rtnl_set_sk_err(struct net *net, u32 group, int error)
{
struct sock *rtnl = net->rtnl;
netlink_set_err(rtnl, 0, group, error);
}
int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
{
struct nlattr *mx;
int i, valid = 0;
mx = nla_nest_start(skb, RTA_METRICS);
if (mx == NULL)
return -ENOBUFS;
for (i = 0; i < RTAX_MAX; i++) {
if (metrics[i]) {
valid++;
NLA_PUT_U32(skb, i+1, metrics[i]);
}
}
if (!valid) {
nla_nest_cancel(skb, mx);
return 0;
}
return nla_nest_end(skb, mx);
nla_put_failure:
nla_nest_cancel(skb, mx);
return -EMSGSIZE;
}
int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id,
u32 ts, u32 tsage, long expires, u32 error)
{
struct rta_cacheinfo ci = {
.rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse),
.rta_used = dst->__use,
.rta_clntref = atomic_read(&(dst->__refcnt)),
.rta_error = error,
.rta_id = id,
.rta_ts = ts,
.rta_tsage = tsage,
};
if (expires)
ci.rta_expires = jiffies_to_clock_t(expires);
return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci);
}
EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo);
static void set_operstate(struct net_device *dev, unsigned char transition)
{
unsigned char operstate = dev->operstate;
switch(transition) {
case IF_OPER_UP:
if ((operstate == IF_OPER_DORMANT ||
operstate == IF_OPER_UNKNOWN) &&
!netif_dormant(dev))
operstate = IF_OPER_UP;
break;
case IF_OPER_DORMANT:
if (operstate == IF_OPER_UP ||
operstate == IF_OPER_UNKNOWN)
operstate = IF_OPER_DORMANT;
break;
}
if (dev->operstate != operstate) {
write_lock_bh(&dev_base_lock);
dev->operstate = operstate;
write_unlock_bh(&dev_base_lock);
netdev_state_change(dev);
}
}
static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
const struct net_device_stats *b)
{
a->rx_packets = b->rx_packets;
a->tx_packets = b->tx_packets;
a->rx_bytes = b->rx_bytes;
a->tx_bytes = b->tx_bytes;
a->rx_errors = b->rx_errors;
a->tx_errors = b->tx_errors;
a->rx_dropped = b->rx_dropped;
a->tx_dropped = b->tx_dropped;
a->multicast = b->multicast;
a->collisions = b->collisions;
a->rx_length_errors = b->rx_length_errors;
a->rx_over_errors = b->rx_over_errors;
a->rx_crc_errors = b->rx_crc_errors;
a->rx_frame_errors = b->rx_frame_errors;
a->rx_fifo_errors = b->rx_fifo_errors;
a->rx_missed_errors = b->rx_missed_errors;
a->tx_aborted_errors = b->tx_aborted_errors;
a->tx_carrier_errors = b->tx_carrier_errors;
a->tx_fifo_errors = b->tx_fifo_errors;
a->tx_heartbeat_errors = b->tx_heartbeat_errors;
a->tx_window_errors = b->tx_window_errors;
a->rx_compressed = b->rx_compressed;
a->tx_compressed = b->tx_compressed;
};
static inline size_t if_nlmsg_size(const struct net_device *dev)
{
return NLMSG_ALIGN(sizeof(struct ifinfomsg))
+ nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
+ nla_total_size(IFALIASZ) /* IFLA_IFALIAS */
+ nla_total_size(IFNAMSIZ) /* IFLA_QDISC */
+ nla_total_size(sizeof(struct rtnl_link_ifmap))
+ nla_total_size(sizeof(struct rtnl_link_stats))
+ nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
+ nla_total_size(MAX_ADDR_LEN) /* IFLA_BROADCAST */
+ nla_total_size(4) /* IFLA_TXQLEN */
+ nla_total_size(4) /* IFLA_WEIGHT */
+ nla_total_size(4) /* IFLA_MTU */
+ nla_total_size(4) /* IFLA_LINK */
+ nla_total_size(4) /* IFLA_MASTER */
+ nla_total_size(1) /* IFLA_OPERSTATE */
+ nla_total_size(1) /* IFLA_LINKMODE */
+ rtnl_link_get_size(dev); /* IFLA_LINKINFO */
}
static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
int type, u32 pid, u32 seq, u32 change,
unsigned int flags)
{
struct netdev_queue *txq;
struct ifinfomsg *ifm;
struct nlmsghdr *nlh;
const struct net_device_stats *stats;
struct nlattr *attr;
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
if (nlh == NULL)
return -EMSGSIZE;
ifm = nlmsg_data(nlh);
ifm->ifi_family = AF_UNSPEC;
ifm->__ifi_pad = 0;
ifm->ifi_type = dev->type;
ifm->ifi_index = dev->ifindex;
ifm->ifi_flags = dev_get_flags(dev);
ifm->ifi_change = change;
NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
NLA_PUT_U8(skb, IFLA_OPERSTATE,
netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
if (dev->ifindex != dev->iflink)
NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
if (dev->master)
NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
txq = netdev_get_tx_queue(dev, 0);
if (txq->qdisc_sleeping)
NLA_PUT_STRING(skb, IFLA_QDISC, txq->qdisc_sleeping->ops->id);
if (dev->ifalias)
NLA_PUT_STRING(skb, IFLA_IFALIAS, dev->ifalias);
if (1) {
struct rtnl_link_ifmap map = {
.mem_start = dev->mem_start,
.mem_end = dev->mem_end,
.base_addr = dev->base_addr,
.irq = dev->irq,
.dma = dev->dma,
.port = dev->if_port,
};
NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
}
if (dev->addr_len) {
NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
}
attr = nla_reserve(skb, IFLA_STATS,
sizeof(struct rtnl_link_stats));
if (attr == NULL)
goto nla_put_failure;
stats = dev_get_stats(dev);
copy_rtnl_link_stats(nla_data(attr), stats);
if (dev->rtnl_link_ops) {
if (rtnl_link_fill(skb, dev) < 0)
goto nla_put_failure;
}
return nlmsg_end(skb, nlh);
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
int idx;
int s_idx = cb->args[0];
struct net_device *dev;
idx = 0;
for_each_netdev(net, dev) {
if (idx < s_idx)
goto cont;
if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
break;
cont:
idx++;
}
cb->args[0] = idx;
return skb->len;
}
const struct nla_policy ifla_policy[IFLA_MAX+1] = {
[IFLA_IFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ-1 },
[IFLA_ADDRESS] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
[IFLA_BROADCAST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
[IFLA_MAP] = { .len = sizeof(struct rtnl_link_ifmap) },
[IFLA_MTU] = { .type = NLA_U32 },
[IFLA_LINK] = { .type = NLA_U32 },
[IFLA_TXQLEN] = { .type = NLA_U32 },
[IFLA_WEIGHT] = { .type = NLA_U32 },
[IFLA_OPERSTATE] = { .type = NLA_U8 },
[IFLA_LINKMODE] = { .type = NLA_U8 },
[IFLA_LINKINFO] = { .type = NLA_NESTED },
[IFLA_NET_NS_PID] = { .type = NLA_U32 },
[IFLA_IFALIAS] = { .type = NLA_STRING, .len = IFALIASZ-1 },
};
static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
[IFLA_INFO_KIND] = { .type = NLA_STRING },
[IFLA_INFO_DATA] = { .type = NLA_NESTED },
};
static struct net *get_net_ns_by_pid(pid_t pid)
{
struct task_struct *tsk;
struct net *net;
/* Lookup the network namespace */
net = ERR_PTR(-ESRCH);
rcu_read_lock();
tsk = find_task_by_vpid(pid);
if (tsk) {
struct nsproxy *nsproxy;
nsproxy = task_nsproxy(tsk);
if (nsproxy)
net = get_net(nsproxy->net_ns);
}
rcu_read_unlock();
return net;
}
static int validate_linkmsg(struct net_device *dev, struct nlattr *tb[])
{
if (dev) {
if (tb[IFLA_ADDRESS] &&
nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
return -EINVAL;
if (tb[IFLA_BROADCAST] &&
nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
return -EINVAL;
}
return 0;
}
static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm,
struct nlattr **tb, char *ifname, int modified)
{
const struct net_device_ops *ops = dev->netdev_ops;
int send_addr_notify = 0;
int err;
if (tb[IFLA_NET_NS_PID]) {
struct net *net;
net = get_net_ns_by_pid(nla_get_u32(tb[IFLA_NET_NS_PID]));
if (IS_ERR(net)) {
err = PTR_ERR(net);
goto errout;
}
err = dev_change_net_namespace(dev, net, ifname);
put_net(net);
if (err)
goto errout;
modified = 1;
}
if (tb[IFLA_MAP]) {
struct rtnl_link_ifmap *u_map;
struct ifmap k_map;
if (!ops->ndo_set_config) {
err = -EOPNOTSUPP;
goto errout;
}
if (!netif_device_present(dev)) {
err = -ENODEV;
goto errout;
}
u_map = nla_data(tb[IFLA_MAP]);
k_map.mem_start = (unsigned long) u_map->mem_start;
k_map.mem_end = (unsigned long) u_map->mem_end;
k_map.base_addr = (unsigned short) u_map->base_addr;
k_map.irq = (unsigned char) u_map->irq;
k_map.dma = (unsigned char) u_map->dma;
k_map.port = (unsigned char) u_map->port;
err = ops->ndo_set_config(dev, &k_map);
if (err < 0)
goto errout;
modified = 1;
}
if (tb[IFLA_ADDRESS]) {
struct sockaddr *sa;
int len;
if (!ops->ndo_set_mac_address) {
err = -EOPNOTSUPP;
goto errout;
}
if (!netif_device_present(dev)) {
err = -ENODEV;
goto errout;
}
len = sizeof(sa_family_t) + dev->addr_len;
sa = kmalloc(len, GFP_KERNEL);
if (!sa) {
err = -ENOMEM;
goto errout;
}
sa->sa_family = dev->type;
memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
dev->addr_len);
err = ops->ndo_set_mac_address(dev, sa);
kfree(sa);
if (err)
goto errout;
send_addr_notify = 1;
modified = 1;
}
if (tb[IFLA_MTU]) {
err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
if (err < 0)
goto errout;
modified = 1;
}
/*
* Interface selected by interface index but interface
* name provided implies that a name change has been
* requested.
*/
if (ifm->ifi_index > 0 && ifname[0]) {
err = dev_change_name(dev, ifname);
if (err < 0)
goto errout;
modified = 1;
}
if (tb[IFLA_IFALIAS]) {
err = dev_set_alias(dev, nla_data(tb[IFLA_IFALIAS]),
nla_len(tb[IFLA_IFALIAS]));
if (err < 0)
goto errout;
modified = 1;
}
if (tb[IFLA_BROADCAST]) {
nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
send_addr_notify = 1;
}
if (ifm->ifi_flags || ifm->ifi_change) {
unsigned int flags = ifm->ifi_flags;
/* bugwards compatibility: ifi_change == 0 is treated as ~0 */
if (ifm->ifi_change)
flags = (flags & ifm->ifi_change) |
(dev->flags & ~ifm->ifi_change);
err = dev_change_flags(dev, flags);
if (err < 0)
goto errout;
}
if (tb[IFLA_TXQLEN])
dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
if (tb[IFLA_OPERSTATE])
set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
if (tb[IFLA_LINKMODE]) {
write_lock_bh(&dev_base_lock);
dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
write_unlock_bh(&dev_base_lock);
}
err = 0;
errout:
if (err < 0 && modified && net_ratelimit())
printk(KERN_WARNING "A link change request failed with "
"some changes comitted already. Interface %s may "
"have been left with an inconsistent configuration, "
"please check.\n", dev->name);
if (send_addr_notify)
call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
return err;
}
static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
struct ifinfomsg *ifm;
struct net_device *dev;
int err;
struct nlattr *tb[IFLA_MAX+1];
char ifname[IFNAMSIZ];
err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
if (err < 0)
goto errout;
if (tb[IFLA_IFNAME])
nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
else
ifname[0] = '\0';
err = -EINVAL;
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0)
dev = dev_get_by_index(net, ifm->ifi_index);
else if (tb[IFLA_IFNAME])
dev = dev_get_by_name(net, ifname);
else
goto errout;
if (dev == NULL) {
err = -ENODEV;
goto errout;
}
if ((err = validate_linkmsg(dev, tb)) < 0)
goto errout_dev;
err = do_setlink(dev, ifm, tb, ifname, 0);
errout_dev:
dev_put(dev);
errout:
return err;
}
static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
const struct rtnl_link_ops *ops;
struct net_device *dev;
struct ifinfomsg *ifm;
char ifname[IFNAMSIZ];
struct nlattr *tb[IFLA_MAX+1];
int err;
err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
if (err < 0)
return err;
if (tb[IFLA_IFNAME])
nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(net, ifm->ifi_index);
else if (tb[IFLA_IFNAME])
dev = __dev_get_by_name(net, ifname);
else
return -EINVAL;
if (!dev)
return -ENODEV;
ops = dev->rtnl_link_ops;
if (!ops)
return -EOPNOTSUPP;
ops->dellink(dev);
return 0;
}
struct net_device *rtnl_create_link(struct net *net, char *ifname,
const struct rtnl_link_ops *ops, struct nlattr *tb[])
{
int err;
struct net_device *dev;
err = -ENOMEM;
dev = alloc_netdev(ops->priv_size, ifname, ops->setup);
if (!dev)
goto err;
if (strchr(dev->name, '%')) {
err = dev_alloc_name(dev, dev->name);
if (err < 0)
goto err_free;
}
dev_net_set(dev, net);
dev->rtnl_link_ops = ops;
if (tb[IFLA_MTU])
dev->mtu = nla_get_u32(tb[IFLA_MTU]);
if (tb[IFLA_ADDRESS])
memcpy(dev->dev_addr, nla_data(tb[IFLA_ADDRESS]),
nla_len(tb[IFLA_ADDRESS]));
if (tb[IFLA_BROADCAST])
memcpy(dev->broadcast, nla_data(tb[IFLA_BROADCAST]),
nla_len(tb[IFLA_BROADCAST]));
if (tb[IFLA_TXQLEN])
dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
if (tb[IFLA_OPERSTATE])
set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
if (tb[IFLA_LINKMODE])
dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
return dev;
err_free:
free_netdev(dev);
err:
return ERR_PTR(err);
}
static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
const struct rtnl_link_ops *ops;
struct net_device *dev;
struct ifinfomsg *ifm;
char kind[MODULE_NAME_LEN];
char ifname[IFNAMSIZ];
struct nlattr *tb[IFLA_MAX+1];
struct nlattr *linkinfo[IFLA_INFO_MAX+1];
int err;
#ifdef CONFIG_MODULES
replay:
#endif
err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
if (err < 0)
return err;
if (tb[IFLA_IFNAME])
nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
else
ifname[0] = '\0';
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(net, ifm->ifi_index);
else if (ifname[0])
dev = __dev_get_by_name(net, ifname);
else
dev = NULL;
if ((err = validate_linkmsg(dev, tb)) < 0)
return err;
if (tb[IFLA_LINKINFO]) {
err = nla_parse_nested(linkinfo, IFLA_INFO_MAX,
tb[IFLA_LINKINFO], ifla_info_policy);
if (err < 0)
return err;
} else
memset(linkinfo, 0, sizeof(linkinfo));
if (linkinfo[IFLA_INFO_KIND]) {
nla_strlcpy(kind, linkinfo[IFLA_INFO_KIND], sizeof(kind));
ops = rtnl_link_ops_get(kind);
} else {
kind[0] = '\0';
ops = NULL;
}
if (1) {
struct nlattr *attr[ops ? ops->maxtype + 1 : 0], **data = NULL;
if (ops) {
if (ops->maxtype && linkinfo[IFLA_INFO_DATA]) {
err = nla_parse_nested(attr, ops->maxtype,
linkinfo[IFLA_INFO_DATA],
ops->policy);
if (err < 0)
return err;
data = attr;
}
if (ops->validate) {
err = ops->validate(tb, data);
if (err < 0)
return err;
}
}
if (dev) {
int modified = 0;
if (nlh->nlmsg_flags & NLM_F_EXCL)
return -EEXIST;
if (nlh->nlmsg_flags & NLM_F_REPLACE)
return -EOPNOTSUPP;
if (linkinfo[IFLA_INFO_DATA]) {
if (!ops || ops != dev->rtnl_link_ops ||
!ops->changelink)
return -EOPNOTSUPP;
err = ops->changelink(dev, tb, data);
if (err < 0)
return err;
modified = 1;
}
return do_setlink(dev, ifm, tb, ifname, modified);
}
if (!(nlh->nlmsg_flags & NLM_F_CREATE))
return -ENODEV;
if (ifm->ifi_index || ifm->ifi_flags || ifm->ifi_change)
return -EOPNOTSUPP;
if (tb[IFLA_MAP] || tb[IFLA_MASTER] || tb[IFLA_PROTINFO])
return -EOPNOTSUPP;
if (!ops) {
#ifdef CONFIG_MODULES
if (kind[0]) {
__rtnl_unlock();
request_module("rtnl-link-%s", kind);
rtnl_lock();
ops = rtnl_link_ops_get(kind);
if (ops)
goto replay;
}
#endif
return -EOPNOTSUPP;
}
if (!ifname[0])
snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
dev = rtnl_create_link(net, ifname, ops, tb);
if (IS_ERR(dev))
err = PTR_ERR(dev);
else if (ops->newlink)
err = ops->newlink(dev, tb, data);
else
err = register_netdevice(dev);
if (err < 0 && !IS_ERR(dev))
free_netdev(dev);
return err;
}
}
static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
struct ifinfomsg *ifm;
struct nlattr *tb[IFLA_MAX+1];
struct net_device *dev = NULL;
struct sk_buff *nskb;
int err;
err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
if (err < 0)
return err;
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0) {
dev = dev_get_by_index(net, ifm->ifi_index);
if (dev == NULL)
return -ENODEV;
} else
return -EINVAL;
nskb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);
if (nskb == NULL) {
err = -ENOBUFS;
goto errout;
}
err = rtnl_fill_ifinfo(nskb, dev, RTM_NEWLINK, NETLINK_CB(skb).pid,
nlh->nlmsg_seq, 0, 0);
if (err < 0) {
/* -EMSGSIZE implies BUG in if_nlmsg_size */
WARN_ON(err == -EMSGSIZE);
kfree_skb(nskb);
goto errout;
}
err = rtnl_unicast(nskb, net, NETLINK_CB(skb).pid);
errout:
dev_put(dev);
return err;
}
static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
{
int idx;
int s_idx = cb->family;
if (s_idx == 0)
s_idx = 1;
for (idx=1; idx<NPROTO; idx++) {
int type = cb->nlh->nlmsg_type-RTM_BASE;
if (idx < s_idx || idx == PF_PACKET)
continue;
if (rtnl_msg_handlers[idx] == NULL ||
rtnl_msg_handlers[idx][type].dumpit == NULL)
continue;
if (idx > s_idx)
memset(&cb->args[0], 0, sizeof(cb->args));
if (rtnl_msg_handlers[idx][type].dumpit(skb, cb))
break;
}
cb->family = idx;
return skb->len;
}
void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
{
struct net *net = dev_net(dev);
struct sk_buff *skb;
int err = -ENOBUFS;
skb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);
if (skb == NULL)
goto errout;
err = rtnl_fill_ifinfo(skb, dev, type, 0, 0, change, 0);
if (err < 0) {
/* -EMSGSIZE implies BUG in if_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
return;
errout:
if (err < 0)
rtnl_set_sk_err(net, RTNLGRP_LINK, err);
}
/* Protected by RTNL sempahore. */
static struct rtattr **rta_buf;
static int rtattr_max;
/* Process one rtnetlink message. */
static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
struct net *net = sock_net(skb->sk);
rtnl_doit_func doit;
int sz_idx, kind;
int min_len;
int family;
int type;
int err;
type = nlh->nlmsg_type;
if (type > RTM_MAX)
return -EOPNOTSUPP;
type -= RTM_BASE;
/* All the messages must have at least 1 byte length */
if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
return 0;
family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
if (family >= NPROTO)
return -EAFNOSUPPORT;
sz_idx = type>>2;
kind = type&3;
if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN))
return -EPERM;
if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
struct sock *rtnl;
rtnl_dumpit_func dumpit;
dumpit = rtnl_get_dumpit(family, type);
if (dumpit == NULL)
return -EOPNOTSUPP;
__rtnl_unlock();
rtnl = net->rtnl;
err = netlink_dump_start(rtnl, skb, nlh, dumpit, NULL);
rtnl_lock();
return err;
}
memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
min_len = rtm_min[sz_idx];
if (nlh->nlmsg_len < min_len)
return -EINVAL;
if (nlh->nlmsg_len > min_len) {
int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
while (RTA_OK(attr, attrlen)) {
unsigned flavor = attr->rta_type;
if (flavor) {
if (flavor > rta_max[sz_idx])
return -EINVAL;
rta_buf[flavor-1] = attr;
}
attr = RTA_NEXT(attr, attrlen);
}
}
doit = rtnl_get_doit(family, type);
if (doit == NULL)
return -EOPNOTSUPP;
return doit(skb, nlh, (void *)&rta_buf[0]);
}
static void rtnetlink_rcv(struct sk_buff *skb)
{
rtnl_lock();
netlink_rcv_skb(skb, &rtnetlink_rcv_msg);
rtnl_unlock();
}
static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
{
struct net_device *dev = ptr;
switch (event) {
case NETDEV_UNREGISTER:
rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
break;
case NETDEV_REGISTER:
rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
break;
case NETDEV_UP:
case NETDEV_DOWN:
rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
break;
case NETDEV_CHANGE:
case NETDEV_GOING_DOWN:
break;
default:
rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
break;
}
return NOTIFY_DONE;
}
static struct notifier_block rtnetlink_dev_notifier = {
.notifier_call = rtnetlink_event,
};
static int rtnetlink_net_init(struct net *net)
{
struct sock *sk;
sk = netlink_kernel_create(net, NETLINK_ROUTE, RTNLGRP_MAX,
rtnetlink_rcv, &rtnl_mutex, THIS_MODULE);
if (!sk)
return -ENOMEM;
net->rtnl = sk;
return 0;
}
static void rtnetlink_net_exit(struct net *net)
{
netlink_kernel_release(net->rtnl);
net->rtnl = NULL;
}
static struct pernet_operations rtnetlink_net_ops = {
.init = rtnetlink_net_init,
.exit = rtnetlink_net_exit,
};
void __init rtnetlink_init(void)
{
int i;
rtattr_max = 0;
for (i = 0; i < ARRAY_SIZE(rta_max); i++)
if (rta_max[i] > rtattr_max)
rtattr_max = rta_max[i];
rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
if (!rta_buf)
panic("rtnetlink_init: cannot allocate rta_buf\n");
if (register_pernet_subsys(&rtnetlink_net_ops))
panic("rtnetlink_init: cannot initialize rtnetlink\n");
netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
register_netdevice_notifier(&rtnetlink_dev_notifier);
rtnl_register(PF_UNSPEC, RTM_GETLINK, rtnl_getlink, rtnl_dump_ifinfo);
rtnl_register(PF_UNSPEC, RTM_SETLINK, rtnl_setlink, NULL);
rtnl_register(PF_UNSPEC, RTM_NEWLINK, rtnl_newlink, NULL);
rtnl_register(PF_UNSPEC, RTM_DELLINK, rtnl_dellink, NULL);
rtnl_register(PF_UNSPEC, RTM_GETADDR, NULL, rtnl_dump_all);
rtnl_register(PF_UNSPEC, RTM_GETROUTE, NULL, rtnl_dump_all);
}
EXPORT_SYMBOL(__rta_fill);
EXPORT_SYMBOL(rtnetlink_put_metrics);
EXPORT_SYMBOL(rtnl_lock);
EXPORT_SYMBOL(rtnl_trylock);
EXPORT_SYMBOL(rtnl_unlock);
EXPORT_SYMBOL(rtnl_is_locked);
EXPORT_SYMBOL(rtnl_unicast);
EXPORT_SYMBOL(rtnl_notify);
EXPORT_SYMBOL(rtnl_set_sk_err);
EXPORT_SYMBOL(rtnl_create_link);
EXPORT_SYMBOL(ifla_policy);