kernel-fxtec-pro1x/include/net/if_inet6.h
Daniel Borkmann 89225d1ce6 net: ipv6: mld: fix v1/v2 switchback timeout to rfc3810, 9.12.
i) RFC3810, 9.2. Query Interval [QI] says:

   The Query Interval variable denotes the interval between General
   Queries sent by the Querier. Default value: 125 seconds. [...]

ii) RFC3810, 9.3. Query Response Interval [QRI] says:

  The Maximum Response Delay used to calculate the Maximum Response
  Code inserted into the periodic General Queries. Default value:
  10000 (10 seconds) [...] The number of seconds represented by the
  [Query Response Interval] must be less than the [Query Interval].

iii) RFC3810, 9.12. Older Version Querier Present Timeout [OVQPT] says:

  The Older Version Querier Present Timeout is the time-out for
  transitioning a host back to MLDv2 Host Compatibility Mode. When an
  MLDv1 query is received, MLDv2 hosts set their Older Version Querier
  Present Timer to [Older Version Querier Present Timeout].

  This value MUST be ([Robustness Variable] times (the [Query Interval]
  in the last Query received)) plus ([Query Response Interval]).

Hence, on *default* the timeout results in:

  [RV] = 2, [QI] = 125sec, [QRI] = 10sec
  [OVQPT] = [RV] * [QI] + [QRI] = 260sec

Having that said, we currently calculate [OVQPT] (here given as 'switchback'
variable) as ...

  switchback = (idev->mc_qrv + 1) * max_delay

RFC3810, 9.12. says "the [Query Interval] in the last Query received". In
section "9.14. Configuring timers", it is said:

  This section is meant to provide advice to network administrators on
  how to tune these settings to their network. Ambitious router
  implementations might tune these settings dynamically based upon
  changing characteristics of the network. [...]

iv) RFC38010, 9.14.2. Query Interval:

  The overall level of periodic MLD traffic is inversely proportional
  to the Query Interval. A longer Query Interval results in a lower
  overall level of MLD traffic. The value of the Query Interval MUST
  be equal to or greater than the Maximum Response Delay used to
  calculate the Maximum Response Code inserted in General Query
  messages.

I assume that was why switchback is calculated as is (3 * max_delay), although
this setting seems to be meant for routers only to configure their [QI]
interval for non-default intervals. So usage here like this is clearly wrong.

Concluding, the current behaviour in IPv6's multicast code is not conform
to the RFC as switch back is calculated wrongly. That is, it has a too small
value, so MLDv2 hosts switch back again to MLDv2 way too early, i.e. ~30secs
instead of ~260secs on default.

Hence, introduce necessary helper functions and fix this up properly as it
should be.

Introduced in 06da92283 ("[IPV6]: Add MLDv2 support."). Credits to Hannes
Frederic Sowa who also had a hand in this as well. Also thanks to Hangbin Liu
who did initial testing.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: David Stevens <dlstevens@us.ibm.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 14:53:20 -04:00

266 lines
6.1 KiB
C

/*
* inet6 interface/address list definitions
* Linux INET6 implementation
*
* Authors:
* Pedro Roque <roque@di.fc.ul.pt>
*
*
* 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.
*/
#ifndef _NET_IF_INET6_H
#define _NET_IF_INET6_H
#include <net/snmp.h>
#include <linux/ipv6.h>
/* inet6_dev.if_flags */
#define IF_RA_OTHERCONF 0x80
#define IF_RA_MANAGED 0x40
#define IF_RA_RCVD 0x20
#define IF_RS_SENT 0x10
#define IF_READY 0x80000000
/* prefix flags */
#define IF_PREFIX_ONLINK 0x01
#define IF_PREFIX_AUTOCONF 0x02
enum {
INET6_IFADDR_STATE_DAD,
INET6_IFADDR_STATE_POSTDAD,
INET6_IFADDR_STATE_UP,
INET6_IFADDR_STATE_DEAD,
};
struct inet6_ifaddr {
struct in6_addr addr;
__u32 prefix_len;
/* In seconds, relative to tstamp. Expiry is at tstamp + HZ * lft. */
__u32 valid_lft;
__u32 prefered_lft;
atomic_t refcnt;
spinlock_t lock;
spinlock_t state_lock;
int state;
__u8 dad_probes;
__u8 flags;
__u16 scope;
unsigned long cstamp; /* created timestamp */
unsigned long tstamp; /* updated timestamp */
struct timer_list dad_timer;
struct inet6_dev *idev;
struct rt6_info *rt;
struct hlist_node addr_lst;
struct list_head if_list;
#ifdef CONFIG_IPV6_PRIVACY
struct list_head tmp_list;
struct inet6_ifaddr *ifpub;
int regen_count;
#endif
bool tokenized;
struct rcu_head rcu;
struct in6_addr peer_addr;
};
struct ip6_sf_socklist {
unsigned int sl_max;
unsigned int sl_count;
struct in6_addr sl_addr[0];
};
#define IP6_SFLSIZE(count) (sizeof(struct ip6_sf_socklist) + \
(count) * sizeof(struct in6_addr))
#define IP6_SFBLOCK 10 /* allocate this many at once */
struct ipv6_mc_socklist {
struct in6_addr addr;
int ifindex;
struct ipv6_mc_socklist __rcu *next;
rwlock_t sflock;
unsigned int sfmode; /* MCAST_{INCLUDE,EXCLUDE} */
struct ip6_sf_socklist *sflist;
struct rcu_head rcu;
};
struct ip6_sf_list {
struct ip6_sf_list *sf_next;
struct in6_addr sf_addr;
unsigned long sf_count[2]; /* include/exclude counts */
unsigned char sf_gsresp; /* include in g & s response? */
unsigned char sf_oldin; /* change state */
unsigned char sf_crcount; /* retrans. left to send */
};
#define MAF_TIMER_RUNNING 0x01
#define MAF_LAST_REPORTER 0x02
#define MAF_LOADED 0x04
#define MAF_NOREPORT 0x08
#define MAF_GSQUERY 0x10
struct ifmcaddr6 {
struct in6_addr mca_addr;
struct inet6_dev *idev;
struct ifmcaddr6 *next;
struct ip6_sf_list *mca_sources;
struct ip6_sf_list *mca_tomb;
unsigned int mca_sfmode;
unsigned char mca_crcount;
unsigned long mca_sfcount[2];
struct timer_list mca_timer;
unsigned int mca_flags;
int mca_users;
atomic_t mca_refcnt;
spinlock_t mca_lock;
unsigned long mca_cstamp;
unsigned long mca_tstamp;
};
/* Anycast stuff */
struct ipv6_ac_socklist {
struct in6_addr acl_addr;
int acl_ifindex;
struct ipv6_ac_socklist *acl_next;
};
struct ifacaddr6 {
struct in6_addr aca_addr;
struct inet6_dev *aca_idev;
struct rt6_info *aca_rt;
struct ifacaddr6 *aca_next;
int aca_users;
atomic_t aca_refcnt;
spinlock_t aca_lock;
unsigned long aca_cstamp;
unsigned long aca_tstamp;
};
#define IFA_HOST IPV6_ADDR_LOOPBACK
#define IFA_LINK IPV6_ADDR_LINKLOCAL
#define IFA_SITE IPV6_ADDR_SITELOCAL
struct ipv6_devstat {
struct proc_dir_entry *proc_dir_entry;
DEFINE_SNMP_STAT(struct ipstats_mib, ipv6);
DEFINE_SNMP_STAT_ATOMIC(struct icmpv6_mib_device, icmpv6dev);
DEFINE_SNMP_STAT_ATOMIC(struct icmpv6msg_mib_device, icmpv6msgdev);
};
struct inet6_dev {
struct net_device *dev;
struct list_head addr_list;
int valid_ll_addr_cnt;
struct ifmcaddr6 *mc_list;
struct ifmcaddr6 *mc_tomb;
spinlock_t mc_lock;
unsigned char mc_qrv; /* Query Robustness Variable */
unsigned char mc_gq_running;
unsigned char mc_ifc_count;
unsigned char mc_dad_count;
unsigned long mc_v1_seen; /* Max time we stay in MLDv1 mode */
unsigned long mc_qi; /* Query Interval */
unsigned long mc_qri; /* Query Response Interval */
unsigned long mc_maxdelay;
struct timer_list mc_gq_timer; /* general query timer */
struct timer_list mc_ifc_timer; /* interface change timer */
struct timer_list mc_dad_timer; /* dad complete mc timer */
struct ifacaddr6 *ac_list;
rwlock_t lock;
atomic_t refcnt;
__u32 if_flags;
int dead;
#ifdef CONFIG_IPV6_PRIVACY
u8 rndid[8];
struct timer_list regen_timer;
struct list_head tempaddr_list;
#endif
struct in6_addr token;
struct neigh_parms *nd_parms;
struct ipv6_devconf cnf;
struct ipv6_devstat stats;
struct timer_list rs_timer;
__u8 rs_probes;
unsigned long tstamp; /* ipv6InterfaceTable update timestamp */
struct rcu_head rcu;
};
static inline void ipv6_eth_mc_map(const struct in6_addr *addr, char *buf)
{
/*
* +-------+-------+-------+-------+-------+-------+
* | 33 | 33 | DST13 | DST14 | DST15 | DST16 |
* +-------+-------+-------+-------+-------+-------+
*/
buf[0]= 0x33;
buf[1]= 0x33;
memcpy(buf + 2, &addr->s6_addr32[3], sizeof(__u32));
}
static inline void ipv6_arcnet_mc_map(const struct in6_addr *addr, char *buf)
{
buf[0] = 0x00;
}
static inline void ipv6_ib_mc_map(const struct in6_addr *addr,
const unsigned char *broadcast, char *buf)
{
unsigned char scope = broadcast[5] & 0xF;
buf[0] = 0; /* Reserved */
buf[1] = 0xff; /* Multicast QPN */
buf[2] = 0xff;
buf[3] = 0xff;
buf[4] = 0xff;
buf[5] = 0x10 | scope; /* scope from broadcast address */
buf[6] = 0x60; /* IPv6 signature */
buf[7] = 0x1b;
buf[8] = broadcast[8]; /* P_Key */
buf[9] = broadcast[9];
memcpy(buf + 10, addr->s6_addr + 6, 10);
}
static inline int ipv6_ipgre_mc_map(const struct in6_addr *addr,
const unsigned char *broadcast, char *buf)
{
if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) {
memcpy(buf, broadcast, 4);
} else {
/* v4mapped? */
if ((addr->s6_addr32[0] | addr->s6_addr32[1] |
(addr->s6_addr32[2] ^ htonl(0x0000ffff))) != 0)
return -EINVAL;
memcpy(buf, &addr->s6_addr32[3], 4);
}
return 0;
}
#endif