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linux/net/core/rtnetlink.c

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/*
* 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 <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);
static struct sock *rtnl;
void rtnl_lock(void)
{
mutex_lock(&rtnl_mutex);
}
void __rtnl_unlock(void)
{
mutex_unlock(&rtnl_mutex);
}
void rtnl_unlock(void)
{
mutex_unlock(&rtnl_mutex);
if (rtnl && rtnl->sk_receive_queue.qlen)
rtnl->sk_data_ready(rtnl, 0);
netdev_run_todo();
}
int rtnl_trylock(void)
{
return mutex_trylock(&rtnl_mutex);
}
int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
{
memset(tb, 0, sizeof(struct rtattr*)*maxattr);
while (RTA_OK(rta, len)) {
unsigned flavor = rta->rta_type;
if (flavor && flavor <= maxattr)
tb[flavor-1] = rta;
rta = RTA_NEXT(rta, len);
}
return 0;
}
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 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);
}
size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
{
size_t ret = RTA_PAYLOAD(rta);
char *src = RTA_DATA(rta);
if (ret > 0 && src[ret - 1] == '\0')
ret--;
if (size > 0) {
size_t len = (ret >= size) ? size - 1 : ret;
memset(dest, 0, size);
memcpy(dest, src, len);
}
return ret;
}
int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
{
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, u32 pid)
{
return nlmsg_unicast(rtnl, skb, pid);
}
int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
struct nlmsghdr *nlh, gfp_t flags)
{
int report = 0;
if (nlh)
report = nlmsg_report(nlh);
return nlmsg_notify(rtnl, skb, pid, group, report, flags);
}
void rtnl_set_sk_err(u32 group, int error)
{
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:
return nla_nest_cancel(skb, mx);
}
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,
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(int iwbuflen)
{
return NLMSG_ALIGN(sizeof(struct ifinfomsg))
+ nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
+ 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 */
+ nla_total_size(iwbuflen);
}
static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
void *iwbuf, int iwbuflen, int type, u32 pid,
u32 seq, u32 change, unsigned int flags)
{
struct ifinfomsg *ifm;
struct nlmsghdr *nlh;
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_U32(skb, IFLA_WEIGHT, dev->weight);
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);
if (dev->qdisc_sleeping)
NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
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);
}
if (dev->get_stats) {
struct net_device_stats *stats = dev->get_stats(dev);
if (stats) {
struct nlattr *attr;
attr = nla_reserve(skb, IFLA_STATS,
sizeof(struct rtnl_link_stats));
if (attr == NULL)
goto nla_put_failure;
copy_rtnl_link_stats(nla_data(attr), stats);
}
}
if (iwbuf)
NLA_PUT(skb, IFLA_WIRELESS, iwbuflen, iwbuf);
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)
{
int idx;
int s_idx = cb->args[0];
struct net_device *dev;
idx = 0;
for_each_netdev(dev) {
if (idx < s_idx)
goto cont;
if (rtnl_fill_ifinfo(skb, dev, NULL, 0, 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;
}
static struct nla_policy ifla_policy[IFLA_MAX+1] __read_mostly = {
[IFLA_IFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ-1 },
[IFLA_MAP] = { .len = sizeof(struct rtnl_link_ifmap) },
[IFLA_MTU] = { .type = NLA_U32 },
[IFLA_TXQLEN] = { .type = NLA_U32 },
[IFLA_WEIGHT] = { .type = NLA_U32 },
[IFLA_OPERSTATE] = { .type = NLA_U8 },
[IFLA_LINKMODE] = { .type = NLA_U8 },
};
static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct ifinfomsg *ifm;
struct net_device *dev;
int err, send_addr_notify = 0, modified = 0;
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(ifm->ifi_index);
else if (tb[IFLA_IFNAME])
dev = dev_get_by_name(ifname);
else
goto errout;
if (dev == NULL) {
err = -ENODEV;
goto errout;
}
if (tb[IFLA_ADDRESS] &&
nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
goto errout_dev;
if (tb[IFLA_BROADCAST] &&
nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
goto errout_dev;
if (tb[IFLA_MAP]) {
struct rtnl_link_ifmap *u_map;
struct ifmap k_map;
if (!dev->set_config) {
err = -EOPNOTSUPP;
goto errout_dev;
}
if (!netif_device_present(dev)) {
err = -ENODEV;
goto errout_dev;
}
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 = dev->set_config(dev, &k_map);
if (err < 0)
goto errout_dev;
modified = 1;
}
if (tb[IFLA_ADDRESS]) {
struct sockaddr *sa;
int len;
if (!dev->set_mac_address) {
err = -EOPNOTSUPP;
goto errout_dev;
}
if (!netif_device_present(dev)) {
err = -ENODEV;
goto errout_dev;
}
len = sizeof(sa_family_t) + dev->addr_len;
sa = kmalloc(len, GFP_KERNEL);
if (!sa) {
err = -ENOMEM;
goto errout_dev;
}
sa->sa_family = dev->type;
memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
dev->addr_len);
err = dev->set_mac_address(dev, sa);
kfree(sa);
if (err)
goto errout_dev;
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_dev;
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_dev;
modified = 1;
}
if (tb[IFLA_BROADCAST]) {
nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
send_addr_notify = 1;
}
if (ifm->ifi_flags)
dev_change_flags(dev, ifm->ifi_flags);
if (tb[IFLA_TXQLEN])
dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
if (tb[IFLA_WEIGHT])
dev->weight = nla_get_u32(tb[IFLA_WEIGHT]);
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_dev:
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);
dev_put(dev);
errout:
return err;
}
static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct ifinfomsg *ifm;
struct nlattr *tb[IFLA_MAX+1];
struct net_device *dev = NULL;
struct sk_buff *nskb;
char *iw_buf = NULL, *iw = NULL;
int iw_buf_len = 0;
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(ifm->ifi_index);
if (dev == NULL)
return -ENODEV;
} else
return -EINVAL;
nskb = nlmsg_new(if_nlmsg_size(iw_buf_len), GFP_KERNEL);
if (nskb == NULL) {
err = -ENOBUFS;
goto errout;
}
err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, 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, NETLINK_CB(skb).pid);
errout:
kfree(iw_buf);
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 sk_buff *skb;
int err = -ENOBUFS;
skb = nlmsg_new(if_nlmsg_size(0), GFP_KERNEL);
if (skb == NULL)
goto errout;
err = rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0);
if (err < 0) {
/* -EMSGSIZE implies BUG in if_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
errout:
if (err < 0)
rtnl_set_sk_err(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)
{
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) {
rtnl_dumpit_func dumpit;
dumpit = rtnl_get_dumpit(family, type);
if (dumpit == NULL)
return -EOPNOTSUPP;
__rtnl_unlock();
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 sock *sk, int len)
{
unsigned int qlen = 0;
do {
mutex_lock(&rtnl_mutex);
netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
mutex_unlock(&rtnl_mutex);
netdev_run_todo();
} while (qlen);
}
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,
};
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");
rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
&rtnl_mutex, THIS_MODULE);
if (rtnl == NULL)
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_GETADDR, NULL, rtnl_dump_all);
rtnl_register(PF_UNSPEC, RTM_GETROUTE, NULL, rtnl_dump_all);
}
EXPORT_SYMBOL(__rta_fill);
EXPORT_SYMBOL(rtattr_strlcpy);
EXPORT_SYMBOL(rtattr_parse);
EXPORT_SYMBOL(rtnetlink_put_metrics);
EXPORT_SYMBOL(rtnl_lock);
EXPORT_SYMBOL(rtnl_trylock);
EXPORT_SYMBOL(rtnl_unlock);
EXPORT_SYMBOL(rtnl_unicast);
EXPORT_SYMBOL(rtnl_notify);
EXPORT_SYMBOL(rtnl_set_sk_err);
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