WSL2-Linux-Kernel/net/l3mdev/l3mdev.c

217 строки
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/l3mdev/l3mdev.c - L3 master device implementation
* Copyright (c) 2015 Cumulus Networks
* Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
*/
#include <linux/netdevice.h>
#include <net/fib_rules.h>
#include <net/l3mdev.h>
/**
* l3mdev_master_ifindex - get index of L3 master device
* @dev: targeted interface
*/
int l3mdev_master_ifindex_rcu(const struct net_device *dev)
{
int ifindex = 0;
if (!dev)
return 0;
if (netif_is_l3_master(dev)) {
ifindex = dev->ifindex;
} else if (netif_is_l3_slave(dev)) {
struct net_device *master;
struct net_device *_dev = (struct net_device *)dev;
/* netdev_master_upper_dev_get_rcu calls
* list_first_or_null_rcu to walk the upper dev list.
* list_first_or_null_rcu does not handle a const arg. We aren't
* making changes, just want the master device from that list so
* typecast to remove the const
*/
master = netdev_master_upper_dev_get_rcu(_dev);
if (master)
ifindex = master->ifindex;
}
return ifindex;
}
EXPORT_SYMBOL_GPL(l3mdev_master_ifindex_rcu);
/**
* l3mdev_master_upper_ifindex_by_index - get index of upper l3 master
* device
* @net: network namespace for device index lookup
* @ifindex: targeted interface
*/
int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
{
struct net_device *dev;
dev = dev_get_by_index_rcu(net, ifindex);
while (dev && !netif_is_l3_master(dev))
dev = netdev_master_upper_dev_get(dev);
return dev ? dev->ifindex : 0;
}
EXPORT_SYMBOL_GPL(l3mdev_master_upper_ifindex_by_index_rcu);
/**
* l3mdev_fib_table - get FIB table id associated with an L3
* master interface
* @dev: targeted interface
*/
u32 l3mdev_fib_table_rcu(const struct net_device *dev)
{
u32 tb_id = 0;
if (!dev)
return 0;
if (netif_is_l3_master(dev)) {
if (dev->l3mdev_ops->l3mdev_fib_table)
tb_id = dev->l3mdev_ops->l3mdev_fib_table(dev);
} else if (netif_is_l3_slave(dev)) {
/* Users of netdev_master_upper_dev_get_rcu need non-const,
* but current inet_*type functions take a const
*/
struct net_device *_dev = (struct net_device *) dev;
const struct net_device *master;
master = netdev_master_upper_dev_get_rcu(_dev);
if (master &&
master->l3mdev_ops->l3mdev_fib_table)
tb_id = master->l3mdev_ops->l3mdev_fib_table(master);
}
return tb_id;
}
EXPORT_SYMBOL_GPL(l3mdev_fib_table_rcu);
u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
{
struct net_device *dev;
u32 tb_id = 0;
if (!ifindex)
return 0;
rcu_read_lock();
dev = dev_get_by_index_rcu(net, ifindex);
if (dev)
tb_id = l3mdev_fib_table_rcu(dev);
rcu_read_unlock();
return tb_id;
}
EXPORT_SYMBOL_GPL(l3mdev_fib_table_by_index);
/**
* l3mdev_link_scope_lookup - IPv6 route lookup based on flow for link
* local and multicast addresses
* @net: network namespace for device index lookup
* @fl6: IPv6 flow struct for lookup
* This function does not hold refcnt on the returned dst.
* Caller must hold rcu_read_lock().
*/
struct dst_entry *l3mdev_link_scope_lookup(struct net *net,
struct flowi6 *fl6)
{
struct dst_entry *dst = NULL;
struct net_device *dev;
WARN_ON_ONCE(!rcu_read_lock_held());
if (fl6->flowi6_oif) {
dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
if (dev && netif_is_l3_slave(dev))
dev = netdev_master_upper_dev_get_rcu(dev);
if (dev && netif_is_l3_master(dev) &&
dev->l3mdev_ops->l3mdev_link_scope_lookup)
dst = dev->l3mdev_ops->l3mdev_link_scope_lookup(dev, fl6);
}
return dst;
}
EXPORT_SYMBOL_GPL(l3mdev_link_scope_lookup);
/**
* l3mdev_fib_rule_match - Determine if flowi references an
* L3 master device
* @net: network namespace for device index lookup
* @fl: flow struct
*/
int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
struct fib_lookup_arg *arg)
{
struct net_device *dev;
int rc = 0;
rcu_read_lock();
dev = dev_get_by_index_rcu(net, fl->flowi_oif);
if (dev && netif_is_l3_master(dev) &&
dev->l3mdev_ops->l3mdev_fib_table) {
arg->table = dev->l3mdev_ops->l3mdev_fib_table(dev);
rc = 1;
goto out;
}
dev = dev_get_by_index_rcu(net, fl->flowi_iif);
if (dev && netif_is_l3_master(dev) &&
dev->l3mdev_ops->l3mdev_fib_table) {
arg->table = dev->l3mdev_ops->l3mdev_fib_table(dev);
rc = 1;
goto out;
}
out:
rcu_read_unlock();
return rc;
}
void l3mdev_update_flow(struct net *net, struct flowi *fl)
{
struct net_device *dev;
int ifindex;
rcu_read_lock();
if (fl->flowi_oif) {
dev = dev_get_by_index_rcu(net, fl->flowi_oif);
if (dev) {
ifindex = l3mdev_master_ifindex_rcu(dev);
if (ifindex) {
fl->flowi_oif = ifindex;
fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
goto out;
}
}
}
if (fl->flowi_iif) {
dev = dev_get_by_index_rcu(net, fl->flowi_iif);
if (dev) {
ifindex = l3mdev_master_ifindex_rcu(dev);
if (ifindex) {
fl->flowi_iif = ifindex;
fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
}
}
}
out:
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(l3mdev_update_flow);