kernel-fxtec-pro1x/net/ipv6/addrconf_core.c
David Ahern 901731b882 net/ipv6: Add helper to return path MTU based on fib result
Determine path MTU from a FIB lookup result. Logic is based on
ip6_dst_mtu_forward plus lookup of nexthop exception.

Add ip6_dst_mtu_forward to ipv6_stubs to handle access by core
bpf code.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-22 10:51:09 +02:00

232 lines
7 KiB
C

/*
* IPv6 library code, needed by static components when full IPv6 support is
* not configured or static.
*/
#include <linux/export.h>
#include <net/ipv6.h>
#include <net/addrconf.h>
#include <net/ip.h>
/* if ipv6 module registers this function is used by xfrm to force all
* sockets to relookup their nodes - this is fairly expensive, be
* careful
*/
void (*__fib6_flush_trees)(struct net *);
EXPORT_SYMBOL(__fib6_flush_trees);
#define IPV6_ADDR_SCOPE_TYPE(scope) ((scope) << 16)
static inline unsigned int ipv6_addr_scope2type(unsigned int scope)
{
switch (scope) {
case IPV6_ADDR_SCOPE_NODELOCAL:
return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_NODELOCAL) |
IPV6_ADDR_LOOPBACK);
case IPV6_ADDR_SCOPE_LINKLOCAL:
return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL) |
IPV6_ADDR_LINKLOCAL);
case IPV6_ADDR_SCOPE_SITELOCAL:
return (IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL) |
IPV6_ADDR_SITELOCAL);
}
return IPV6_ADDR_SCOPE_TYPE(scope);
}
int __ipv6_addr_type(const struct in6_addr *addr)
{
__be32 st;
st = addr->s6_addr32[0];
/* Consider all addresses with the first three bits different of
000 and 111 as unicasts.
*/
if ((st & htonl(0xE0000000)) != htonl(0x00000000) &&
(st & htonl(0xE0000000)) != htonl(0xE0000000))
return (IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL));
if ((st & htonl(0xFF000000)) == htonl(0xFF000000)) {
/* multicast */
/* addr-select 3.1 */
return (IPV6_ADDR_MULTICAST |
ipv6_addr_scope2type(IPV6_ADDR_MC_SCOPE(addr)));
}
if ((st & htonl(0xFFC00000)) == htonl(0xFE800000))
return (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL)); /* addr-select 3.1 */
if ((st & htonl(0xFFC00000)) == htonl(0xFEC00000))
return (IPV6_ADDR_SITELOCAL | IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_SITELOCAL)); /* addr-select 3.1 */
if ((st & htonl(0xFE000000)) == htonl(0xFC000000))
return (IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL)); /* RFC 4193 */
if ((addr->s6_addr32[0] | addr->s6_addr32[1]) == 0) {
if (addr->s6_addr32[2] == 0) {
if (addr->s6_addr32[3] == 0)
return IPV6_ADDR_ANY;
if (addr->s6_addr32[3] == htonl(0x00000001))
return (IPV6_ADDR_LOOPBACK | IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_LINKLOCAL)); /* addr-select 3.4 */
return (IPV6_ADDR_COMPATv4 | IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL)); /* addr-select 3.3 */
}
if (addr->s6_addr32[2] == htonl(0x0000ffff))
return (IPV6_ADDR_MAPPED |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL)); /* addr-select 3.3 */
}
return (IPV6_ADDR_UNICAST |
IPV6_ADDR_SCOPE_TYPE(IPV6_ADDR_SCOPE_GLOBAL)); /* addr-select 3.4 */
}
EXPORT_SYMBOL(__ipv6_addr_type);
static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
static BLOCKING_NOTIFIER_HEAD(inet6addr_validator_chain);
int register_inet6addr_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_register(&inet6addr_chain, nb);
}
EXPORT_SYMBOL(register_inet6addr_notifier);
int unregister_inet6addr_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
}
EXPORT_SYMBOL(unregister_inet6addr_notifier);
int inet6addr_notifier_call_chain(unsigned long val, void *v)
{
return atomic_notifier_call_chain(&inet6addr_chain, val, v);
}
EXPORT_SYMBOL(inet6addr_notifier_call_chain);
int register_inet6addr_validator_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&inet6addr_validator_chain, nb);
}
EXPORT_SYMBOL(register_inet6addr_validator_notifier);
int unregister_inet6addr_validator_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&inet6addr_validator_chain,
nb);
}
EXPORT_SYMBOL(unregister_inet6addr_validator_notifier);
int inet6addr_validator_notifier_call_chain(unsigned long val, void *v)
{
return blocking_notifier_call_chain(&inet6addr_validator_chain, val, v);
}
EXPORT_SYMBOL(inet6addr_validator_notifier_call_chain);
static int eafnosupport_ipv6_dst_lookup(struct net *net, struct sock *u1,
struct dst_entry **u2,
struct flowi6 *u3)
{
return -EAFNOSUPPORT;
}
static struct fib6_table *eafnosupport_fib6_get_table(struct net *net, u32 id)
{
return NULL;
}
static struct fib6_info *
eafnosupport_fib6_table_lookup(struct net *net, struct fib6_table *table,
int oif, struct flowi6 *fl6, int flags)
{
return NULL;
}
static struct fib6_info *
eafnosupport_fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
int flags)
{
return NULL;
}
static struct fib6_info *
eafnosupport_fib6_multipath_select(const struct net *net, struct fib6_info *f6i,
struct flowi6 *fl6, int oif,
const struct sk_buff *skb, int strict)
{
return f6i;
}
static u32
eafnosupport_ip6_mtu_from_fib6(struct fib6_info *f6i, struct in6_addr *daddr,
struct in6_addr *saddr)
{
return 0;
}
const struct ipv6_stub *ipv6_stub __read_mostly = &(struct ipv6_stub) {
.ipv6_dst_lookup = eafnosupport_ipv6_dst_lookup,
.fib6_get_table = eafnosupport_fib6_get_table,
.fib6_table_lookup = eafnosupport_fib6_table_lookup,
.fib6_lookup = eafnosupport_fib6_lookup,
.fib6_multipath_select = eafnosupport_fib6_multipath_select,
.ip6_mtu_from_fib6 = eafnosupport_ip6_mtu_from_fib6,
};
EXPORT_SYMBOL_GPL(ipv6_stub);
/* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
EXPORT_SYMBOL(in6addr_loopback);
const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
EXPORT_SYMBOL(in6addr_any);
const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
EXPORT_SYMBOL(in6addr_linklocal_allnodes);
const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
EXPORT_SYMBOL(in6addr_linklocal_allrouters);
const struct in6_addr in6addr_interfacelocal_allnodes = IN6ADDR_INTERFACELOCAL_ALLNODES_INIT;
EXPORT_SYMBOL(in6addr_interfacelocal_allnodes);
const struct in6_addr in6addr_interfacelocal_allrouters = IN6ADDR_INTERFACELOCAL_ALLROUTERS_INIT;
EXPORT_SYMBOL(in6addr_interfacelocal_allrouters);
const struct in6_addr in6addr_sitelocal_allrouters = IN6ADDR_SITELOCAL_ALLROUTERS_INIT;
EXPORT_SYMBOL(in6addr_sitelocal_allrouters);
static void snmp6_free_dev(struct inet6_dev *idev)
{
kfree(idev->stats.icmpv6msgdev);
kfree(idev->stats.icmpv6dev);
free_percpu(idev->stats.ipv6);
}
static void in6_dev_finish_destroy_rcu(struct rcu_head *head)
{
struct inet6_dev *idev = container_of(head, struct inet6_dev, rcu);
snmp6_free_dev(idev);
kfree(idev);
}
/* Nobody refers to this device, we may destroy it. */
void in6_dev_finish_destroy(struct inet6_dev *idev)
{
struct net_device *dev = idev->dev;
WARN_ON(!list_empty(&idev->addr_list));
WARN_ON(idev->mc_list);
WARN_ON(timer_pending(&idev->rs_timer));
#ifdef NET_REFCNT_DEBUG
pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
#endif
dev_put(dev);
if (!idev->dead) {
pr_warn("Freeing alive inet6 device %p\n", idev);
return;
}
call_rcu(&idev->rcu, in6_dev_finish_destroy_rcu);
}
EXPORT_SYMBOL(in6_dev_finish_destroy);