linux/include/net/addrconf.h
Florian Westphal 2a7851bffb netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6
Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812:

[ ip6tables -m addrtype ]
When I tried to use in the nat/PREROUTING it messes up the
routing cache even if the rule didn't matched at all.
[..]
If I remove the --limit-iface-in from the non-working scenario, so just
use the -m addrtype --dst-type LOCAL it works!

This happens when LOCAL type matching is requested with --limit-iface-in,
and the default ipv6 route is via the interface the packet we test
arrived on.

Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation
creates an unwanted cached entry, and the packet won't make it to the
real/expected destination.

Silently ignoring --limit-iface-in makes the routing work but it breaks
rule matching (--dst-type LOCAL with limit-iface-in is supposed to only
match if the dst address is configured on the incoming interface;
without --limit-iface-in it will match if the address is reachable
via lo).

The test should call ipv6_chk_addr() instead.  However, this would add
a link-time dependency on ipv6.

There are two possible solutions:

1) Revert the commit that moved ipt_addrtype to xt_addrtype,
   and put ipv6 specific code into ip6t_addrtype.
2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions.

While the former might seem preferable, Pablo pointed out that there
are more xt modules with link-time dependeny issues regarding ipv6,
so lets go for 2).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-23 11:58:55 +02:00

344 lines
9.4 KiB
C

#ifndef _ADDRCONF_H
#define _ADDRCONF_H
#define MAX_RTR_SOLICITATIONS 3
#define RTR_SOLICITATION_INTERVAL (4*HZ)
#define MIN_VALID_LIFETIME (2*3600) /* 2 hours */
#define TEMP_VALID_LIFETIME (7*86400)
#define TEMP_PREFERRED_LIFETIME (86400)
#define REGEN_MAX_RETRY (3)
#define MAX_DESYNC_FACTOR (600)
#define ADDR_CHECK_FREQUENCY (120*HZ)
#define IPV6_MAX_ADDRESSES 16
#define ADDRCONF_TIMER_FUZZ_MINUS (HZ > 50 ? HZ / 50 : 1)
#define ADDRCONF_TIMER_FUZZ (HZ / 4)
#define ADDRCONF_TIMER_FUZZ_MAX (HZ)
#include <linux/in.h>
#include <linux/in6.h>
struct prefix_info {
__u8 type;
__u8 length;
__u8 prefix_len;
#if defined(__BIG_ENDIAN_BITFIELD)
__u8 onlink : 1,
autoconf : 1,
reserved : 6;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
__u8 reserved : 6,
autoconf : 1,
onlink : 1;
#else
#error "Please fix <asm/byteorder.h>"
#endif
__be32 valid;
__be32 prefered;
__be32 reserved2;
struct in6_addr prefix;
};
#include <linux/netdevice.h>
#include <net/if_inet6.h>
#include <net/ipv6.h>
#define IN6_ADDR_HSIZE_SHIFT 4
#define IN6_ADDR_HSIZE (1 << IN6_ADDR_HSIZE_SHIFT)
extern int addrconf_init(void);
extern void addrconf_cleanup(void);
extern int addrconf_add_ifaddr(struct net *net,
void __user *arg);
extern int addrconf_del_ifaddr(struct net *net,
void __user *arg);
extern int addrconf_set_dstaddr(struct net *net,
void __user *arg);
extern int ipv6_chk_addr(struct net *net,
const struct in6_addr *addr,
const struct net_device *dev,
int strict);
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
extern int ipv6_chk_home_addr(struct net *net,
const struct in6_addr *addr);
#endif
extern int ipv6_chk_prefix(const struct in6_addr *addr,
struct net_device *dev);
extern struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
const struct in6_addr *addr,
struct net_device *dev,
int strict);
extern int ipv6_dev_get_saddr(struct net *net,
const struct net_device *dev,
const struct in6_addr *daddr,
unsigned int srcprefs,
struct in6_addr *saddr);
extern int ipv6_get_lladdr(struct net_device *dev,
struct in6_addr *addr,
unsigned char banned_flags);
extern int ipv6_rcv_saddr_equal(const struct sock *sk,
const struct sock *sk2);
extern void addrconf_join_solict(struct net_device *dev,
const struct in6_addr *addr);
extern void addrconf_leave_solict(struct inet6_dev *idev,
const struct in6_addr *addr);
static inline unsigned long addrconf_timeout_fixup(u32 timeout,
unsigned int unit)
{
if (timeout == 0xffffffff)
return ~0UL;
/*
* Avoid arithmetic overflow.
* Assuming unit is constant and non-zero, this "if" statement
* will go away on 64bit archs.
*/
if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
return LONG_MAX / unit;
return timeout;
}
static inline int addrconf_finite_timeout(unsigned long timeout)
{
return ~timeout;
}
/*
* IPv6 Address Label subsystem (addrlabel.c)
*/
extern int ipv6_addr_label_init(void);
extern void ipv6_addr_label_cleanup(void);
extern void ipv6_addr_label_rtnl_register(void);
extern u32 ipv6_addr_label(struct net *net,
const struct in6_addr *addr,
int type, int ifindex);
/*
* multicast prototypes (mcast.c)
*/
extern int ipv6_sock_mc_join(struct sock *sk, int ifindex,
const struct in6_addr *addr);
extern int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
const struct in6_addr *addr);
extern void ipv6_sock_mc_close(struct sock *sk);
extern bool inet6_mc_check(struct sock *sk,
const struct in6_addr *mc_addr,
const struct in6_addr *src_addr);
extern int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
extern int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
extern int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
extern void ipv6_mc_up(struct inet6_dev *idev);
extern void ipv6_mc_down(struct inet6_dev *idev);
extern void ipv6_mc_unmap(struct inet6_dev *idev);
extern void ipv6_mc_remap(struct inet6_dev *idev);
extern void ipv6_mc_init_dev(struct inet6_dev *idev);
extern void ipv6_mc_destroy_dev(struct inet6_dev *idev);
extern void addrconf_dad_failure(struct inet6_ifaddr *ifp);
extern bool ipv6_chk_mcast_addr(struct net_device *dev,
const struct in6_addr *group,
const struct in6_addr *src_addr);
/*
* identify MLD packets for MLD filter exceptions
*/
static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
{
struct icmp6hdr *hdr;
if (nexthdr != IPPROTO_ICMPV6 ||
!pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
return false;
hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
switch (hdr->icmp6_type) {
case ICMPV6_MGM_QUERY:
case ICMPV6_MGM_REPORT:
case ICMPV6_MGM_REDUCTION:
case ICMPV6_MLD2_REPORT:
return true;
default:
break;
}
return false;
}
extern void addrconf_prefix_rcv(struct net_device *dev,
u8 *opt, int len, bool sllao);
/*
* anycast prototypes (anycast.c)
*/
extern int ipv6_sock_ac_join(struct sock *sk,int ifindex, const struct in6_addr *addr);
extern int ipv6_sock_ac_drop(struct sock *sk,int ifindex, const struct in6_addr *addr);
extern void ipv6_sock_ac_close(struct sock *sk);
extern int ipv6_dev_ac_inc(struct net_device *dev, const struct in6_addr *addr);
extern int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
extern bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
const struct in6_addr *addr);
/* Device notifier */
extern int register_inet6addr_notifier(struct notifier_block *nb);
extern int unregister_inet6addr_notifier(struct notifier_block *nb);
extern int inet6addr_notifier_call_chain(unsigned long val, void *v);
extern void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
struct ipv6_devconf *devconf);
/**
* __in6_dev_get - get inet6_dev pointer from netdevice
* @dev: network device
*
* Caller must hold rcu_read_lock or RTNL, because this function
* does not take a reference on the inet6_dev.
*/
static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
{
return rcu_dereference_rtnl(dev->ip6_ptr);
}
/**
* in6_dev_get - get inet6_dev pointer from netdevice
* @dev: network device
*
* This version can be used in any context, and takes a reference
* on the inet6_dev. Callers must use in6_dev_put() later to
* release this reference.
*/
static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
{
struct inet6_dev *idev;
rcu_read_lock();
idev = rcu_dereference(dev->ip6_ptr);
if (idev)
atomic_inc(&idev->refcnt);
rcu_read_unlock();
return idev;
}
extern void in6_dev_finish_destroy(struct inet6_dev *idev);
static inline void in6_dev_put(struct inet6_dev *idev)
{
if (atomic_dec_and_test(&idev->refcnt))
in6_dev_finish_destroy(idev);
}
static inline void __in6_dev_put(struct inet6_dev *idev)
{
atomic_dec(&idev->refcnt);
}
static inline void in6_dev_hold(struct inet6_dev *idev)
{
atomic_inc(&idev->refcnt);
}
extern void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
{
if (atomic_dec_and_test(&ifp->refcnt))
inet6_ifa_finish_destroy(ifp);
}
static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
{
atomic_dec(&ifp->refcnt);
}
static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
{
atomic_inc(&ifp->refcnt);
}
/*
* compute link-local solicited-node multicast address
*/
static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
struct in6_addr *solicited)
{
ipv6_addr_set(solicited,
htonl(0xFF020000), 0,
htonl(0x1),
htonl(0xFF000000) | addr->s6_addr32[3]);
}
static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr)
{
return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000);
}
static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__u64 *p = (__u64 *)addr;
return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
#else
return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
addr->s6_addr32[1] | addr->s6_addr32[2] |
(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
#endif
}
static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__u64 *p = (__u64 *)addr;
return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
#else
return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
addr->s6_addr32[1] | addr->s6_addr32[2] |
(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
#endif
}
static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
{
return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
}
static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__u64 *p = (__u64 *)addr;
return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
cpu_to_be64(0xffffffffff000000UL))) == 0UL;
#else
return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
addr->s6_addr32[1] |
(addr->s6_addr32[2] ^ htonl(0x00000001)) |
(addr->s6_addr[12] ^ 0xff)) == 0;
#endif
}
#ifdef CONFIG_PROC_FS
extern int if6_proc_init(void);
extern void if6_proc_exit(void);
#endif
#endif