Commit Graph

63 Commits

Author SHA1 Message Date
Gustavo A. R. Silva
0fa39d6dd0 ipv6: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-11 13:18:54 -07:00
Fernando Gont
969c54646a ipv6: Implement draft-ietf-6man-rfc4941bis
Implement the upcoming rev of RFC4941 (IPv6 temporary addresses):
https://tools.ietf.org/html/draft-ietf-6man-rfc4941bis-09

* Reduces the default Valid Lifetime to 2 days
  The number of extra addresses employed when Valid Lifetime was
  7 days exacerbated the stress caused on network
  elements/devices. Additionally, the motivation for temporary
  addresses is indeed privacy and reduced exposure. With a
  default Valid Lifetime of 7 days, an address that becomes
  revealed by active communication is reachable and exposed for
  one whole week. The only use case for a Valid Lifetime of 7
  days could be some application that is expecting to have long
  lived connections. But if you want to have a long lived
  connections, you shouldn't be using a temporary address in the
  first place. Additionally, in the era of mobile devices, general
  applications should nevertheless be prepared and robust to
  address changes (e.g. nodes swap wifi <-> 4G, etc.)

* Employs different IIDs for different prefixes
  To avoid network activity correlation among addresses configured
  for different prefixes

* Uses a simpler algorithm for IID generation
  No need to store "history" anywhere

Signed-off-by: Fernando Gont <fgont@si6networks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 17:00:02 -07:00
Eric Dumazet
14105c191e ipv6: shrink struct ipv6_mc_socklist
Remove two holes on 64bit arches, to bring the size
to one cache line exactly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-28 14:43:03 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Jeff Barnhill
2384d02520 net/ipv6: Add anycast addresses to a global hashtable
icmp6_send() function is expensive on systems with a large number of
interfaces. Every time it’s called, it has to verify that the source
address does not correspond to an existing anycast address by looping
through every device and every anycast address on the device.  This can
result in significant delays for a CPU when there are a large number of
neighbors and ND timers are frequently timing out and calling
neigh_invalidate().

Add anycast addresses to a global hashtable to allow quick searching for
matching anycast addresses.  This is based on inet6_addr_lst in addrconf.c.

Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-02 23:54:56 -07:00
David Ahern
8308f3ff17 net/ipv6: Add support for specifying metric of connected routes
Add support for IFA_RT_PRIORITY to ipv6 addresses.

If the metric is changed on an existing address then the new route
is inserted before removing the old one. Since the metric is one
of the route keys, the prefix route can not be atomically replaced.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-29 10:12:45 -04:00
David Ahern
9ee8cbb2fd net/ipv6: Remove aca_idev
aca_idev has only 1 user - inet6_fill_ifacaddr - and it only
wants the device index which can be extracted from the fib6_info
nexthop.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-19 15:40:13 -04:00
David Ahern
8d1c802b28 net/ipv6: Flip FIB entries to fib6_info
Convert all code paths referencing a FIB entry from
rt6_info to fib6_info.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 23:41:18 -04:00
Reshetova, Elena
affa78bc6a net, ipv6: convert ifacaddr6.aca_refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04 01:29:04 -07:00
Reshetova, Elena
d3981bc615 net, ipv6: convert ifmcaddr6.mca_refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04 01:29:04 -07:00
Reshetova, Elena
271201c09c net, ipv6: convert inet6_ifaddr.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04 01:29:04 -07:00
Reshetova, Elena
1be9246077 net, ipv6: convert inet6_dev.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-04 01:29:04 -07:00
Felix Jia
d35a00b8e3 net/ipv6: allow sysctl to change link-local address generation mode
The address generation mode for IPv6 link-local can only be configured
by netlink messages. This patch adds the ability to change the address
generation mode via sysctl.

v1 -> v2
Removed the rtnl lock and switch to use RCU lock to iterate through
the netdev list.

v2 -> v3
Removed the addrgenmode variable from the idev structure and use the
systcl storage for the flag.

Simplifed the logic for sysctl handling by removing the supported
for all operation.

Added support for more types of tunnel interfaces for link-local
address generation.

Based the patches from net-next.

v3 -> v4
Removed unnecessary whitespace changes.

Signed-off-by: Felix Jia <felix.jia@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-27 10:25:34 -05:00
Erik Nordmark
adc176c547 ipv6 addrconf: Implemented enhanced DAD (RFC7527)
Implemented RFC7527 Enhanced DAD.
IPv6 duplicate address detection can fail if there is some temporary
loopback of Ethernet frames. RFC7527 solves this by including a random
nonce in the NS messages used for DAD, and if an NS is received with the
same nonce it is assumed to be a looped back DAD probe and is ignored.
RFC7527 is enabled by default. Can be disabled by setting both of
conf/{all,interface}/enhanced_dad to zero.

Signed-off-by: Erik Nordmark <nordmark@arista.com>
Signed-off-by: Bob Gilligan <gilligan@arista.com>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 23:21:37 -05:00
Jiri Bohac
76506a986d IPv6: fix DESYNC_FACTOR
The IPv6 temporary address generation uses a variable called DESYNC_FACTOR
to prevent hosts updating the addresses at the same time. Quoting RFC 4941:

   ... The value DESYNC_FACTOR is a random value (different for each
   client) that ensures that clients don't synchronize with each other and
   generate new addresses at exactly the same time ...

DESYNC_FACTOR is defined as:

   DESYNC_FACTOR -- A random value within the range 0 - MAX_DESYNC_FACTOR.
   It is computed once at system start (rather than each time it is used)
   and must never be greater than (TEMP_VALID_LIFETIME - REGEN_ADVANCE).

First, I believe the RFC has a typo in it and meant to say: "and must
never be greater than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE)"

The reason is that at various places in the RFC, DESYNC_FACTOR is used in
a calculation like (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR) or
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE - DESYNC_FACTOR). It needs to be
smaller than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE) for the result of
these calculations to be larger than zero. It's never used in a
calculation together with TEMP_VALID_LIFETIME.

I already submitted an errata to the rfc-editor:
https://www.rfc-editor.org/errata_search.php?rfc=4941

The Linux implementation of DESYNC_FACTOR is very wrong:
max_desync_factor is used in places DESYNC_FACTOR should be used.
max_desync_factor is initialized to the RFC-recommended value for
MAX_DESYNC_FACTOR (600) but the whole point is to get a _random_ value.

And nothing ensures that the value used is not greater than
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE), which leads to underflows.  The
effect can easily be observed when setting the temp_prefered_lft sysctl
e.g. to 60. The preferred lifetime of the temporary addresses will be
bogus.

TEMP_PREFERRED_LIFETIME and REGEN_ADVANCE are not constants and can be
influenced by these three sysctls: regen_max_retry, dad_transmits and
temp_prefered_lft. Thus, the upper bound for desync_factor needs to be
re-calculated each time a new address is generated and if desync_factor is
larger than the new upper bound, a new random value needs to be
re-generated.

And since we already have max_desync_factor configurable per interface, we
also need to calculate and store desync_factor per interface.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:59:15 -04:00
Jiri Bohac
9d6280da39 IPv6: Drop the temporary address regen_timer
The randomized interface identifier (rndid) was periodically updated from
the regen_timer timer. Simplify the code by updating the rndid only when
needed by ipv6_try_regen_rndid().

This makes the follow-up DESYNC_FACTOR fix much simpler.  Also it fixes a
reference counting error in this error path, where an in6_dev_put was
missing:
		err = addrconf_sysctl_register(ndev);
		if (err) {
			ipv6_mc_destroy_dev(ndev);
	-               del_timer(&ndev->regen_timer);
			snmp6_unregister_dev(ndev);
			goto err_release;

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:59:15 -04:00
Maciej Żenczykowski
bd11f0741f ipv6 addrconf: implement RFC7559 router solicitation backoff
This implements:
  https://tools.ietf.org/html/rfc7559

Backoff is performed according to RFC3315 section 14:
  https://tools.ietf.org/html/rfc3315#section-14

We allow setting /proc/sys/net/ipv6/conf/*/router_solicitations
to a negative value meaning an unlimited number of retransmits,
and we make this the new default (inline with the RFC).

We also add a new setting:
  /proc/sys/net/ipv6/conf/*/router_solicitation_max_interval
defaulting to 1 hour (per RFC recommendation).

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30 01:54:28 -04:00
Hannes Frederic Sowa
5f40ef77ad ipv6: do retries on stable privacy addresses
If a DAD conflict is detected, we want to retry privacy stable address
generation up to idgen_retries (= 3) times with a delay of idgen_delay
(= 1 second). Add the logic to addrconf_dad_failure.

By design, we don't clean up dad failed permanent addresses.

Cc: Erik Kline <ek@google.com>
Cc: Fernando Gont <fgont@si6networks.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-23 22:12:09 -04:00
Hannes Frederic Sowa
8e8e676d0b ipv6: collapse state_lock and lock
Cc: Erik Kline <ek@google.com>
Cc: Fernando Gont <fgont@si6networks.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-23 22:12:09 -04:00
Li RongQing
02ea80741a ipv6: remove aca_lock spinlock from struct ifacaddr6
no user uses this lock.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14 13:15:15 -04:00
Sébastien Barré
dd3619f2ed Removed unused inet6 address state
the inet6 state INET6_IFADDR_STATE_UP only appeared in its definition.

Cc: Christoph Paasch <christoph.paasch@uclouvain.be>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sébastien Barré <sebastien.barre@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-04 20:37:17 -04:00
Jiri Pirko
bc91b0f07a ipv6: addrconf: implement address generation modes
This patch introduces a possibility for userspace to set various (so far
two) modes of generating addresses. This is useful for example for
NetworkManager because it can set the mode to NONE and take care of link
local addresses itself. That allow it to have the interface up,
monitoring carrier but still don't have any addresses on it.

One more use-case by Dan Williams:
<quote>
WWAN devices often have their LL address provided by the firmware of the
device, which sometimes refuses to respond to incorrect LL addresses
when doing DHCPv6 or IPv6 ND.  The kernel cannot generate the correct LL
address for two reasons:

1) WWAN pseudo-ethernet interfaces often construct a fake MAC address,
or read a meaningless MAC address from the firmware.  Thus the EUI64 and
the IPv6LL address the kernel assigns will be wrong.  The real LL
address is often retrieved from the firmware with AT or proprietary
commands.

2) WWAN PPP interfaces receive their LL address from IPV6CP, not from
kernel assignments.  Only after IPV6CP has completed do we know the LL
address of the PPP interface and its peer.  But the kernel has already
assigned an incorrect LL address to the interface.

So being able to suppress the kernel LL address generation and assign
the one retrieved from the firmware is less complicated and more robust.
</quote>

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-11 15:05:45 -07:00
Hannes Frederic Sowa
c15b1ccadb ipv6: move DAD and addrconf_verify processing to workqueue
addrconf_join_solict and addrconf_join_anycast may cause actions which
need rtnl locked, especially on first address creation.

A new DAD state is introduced which defers processing of the initial
DAD processing into a workqueue.

To get rtnl lock we need to push the code paths which depend on those
calls up to workqueues, specifically addrconf_verify and the DAD
processing.

(v2)
addrconf_dad_failure needs to be queued up to the workqueue, too. This
patch introduces a new DAD state and stop the DAD processing in the
workqueue (this is because of the possible ipv6_del_addr processing
which removes the solicited multicast address from the device).

addrconf_verify_lock is removed, too. After the transition it is not
needed any more.

As we are not processing in bottom half anymore we need to be a bit more
careful about disabling bottom half out when we lock spin_locks which are also
used in bh.

Relevant backtrace:
[  541.030090] RTNL: assertion failed at net/core/dev.c (4496)
[  541.031143] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G           O 3.10.33-1-amd64-vyatta #1
[  541.031145] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[  541.031146]  ffffffff8148a9f0 000000000000002f ffffffff813c98c1 ffff88007c4451f8
[  541.031148]  0000000000000000 0000000000000000 ffffffff813d3540 ffff88007fc03d18
[  541.031150]  0000880000000006 ffff88007c445000 ffffffffa0194160 0000000000000000
[  541.031152] Call Trace:
[  541.031153]  <IRQ>  [<ffffffff8148a9f0>] ? dump_stack+0xd/0x17
[  541.031180]  [<ffffffff813c98c1>] ? __dev_set_promiscuity+0x101/0x180
[  541.031183]  [<ffffffff813d3540>] ? __hw_addr_create_ex+0x60/0xc0
[  541.031185]  [<ffffffff813cfe1a>] ? __dev_set_rx_mode+0xaa/0xc0
[  541.031189]  [<ffffffff813d3a81>] ? __dev_mc_add+0x61/0x90
[  541.031198]  [<ffffffffa01dcf9c>] ? igmp6_group_added+0xfc/0x1a0 [ipv6]
[  541.031208]  [<ffffffff8111237b>] ? kmem_cache_alloc+0xcb/0xd0
[  541.031212]  [<ffffffffa01ddcd7>] ? ipv6_dev_mc_inc+0x267/0x300 [ipv6]
[  541.031216]  [<ffffffffa01c2fae>] ? addrconf_join_solict+0x2e/0x40 [ipv6]
[  541.031219]  [<ffffffffa01ba2e9>] ? ipv6_dev_ac_inc+0x159/0x1f0 [ipv6]
[  541.031223]  [<ffffffffa01c0772>] ? addrconf_join_anycast+0x92/0xa0 [ipv6]
[  541.031226]  [<ffffffffa01c311e>] ? __ipv6_ifa_notify+0x11e/0x1e0 [ipv6]
[  541.031229]  [<ffffffffa01c3213>] ? ipv6_ifa_notify+0x33/0x50 [ipv6]
[  541.031233]  [<ffffffffa01c36c8>] ? addrconf_dad_completed+0x28/0x100 [ipv6]
[  541.031241]  [<ffffffff81075c1d>] ? task_cputime+0x2d/0x50
[  541.031244]  [<ffffffffa01c38d6>] ? addrconf_dad_timer+0x136/0x150 [ipv6]
[  541.031247]  [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
[  541.031255]  [<ffffffff8105313a>] ? call_timer_fn.isra.22+0x2a/0x90
[  541.031258]  [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]

Hunks and backtrace stolen from a patch by Stephen Hemminger.

Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-28 16:54:50 -04:00
David S. Miller
4180442058 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
	net/ipv4/tcp_metrics.c

Overlapping changes between the "don't create two tcp metrics objects
with the same key" race fix in net and the addition of the destination
address in the lookup key in net-next.

Minor overlapping changes in bnx2x driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-18 00:55:41 -08:00
Hannes Frederic Sowa
11ffff752c ipv6: simplify detection of first operational link-local address on interface
In commit 1ec047eb47 ("ipv6: introduce per-interface counter for
dad-completed ipv6 addresses") I build the detection of the first
operational link-local address much to complex. Additionally this code
now has a race condition.

Replace it with a much simpler variant, which just scans the address
list when duplicate address detection completes, to check if this is
the first valid link local address and send RS and MLD reports then.

Fixes: 1ec047eb47 ("ipv6: introduce per-interface counter for dad-completed ipv6 addresses")
Reported-by: Jiri Pirko <jiri@resnulli.us>
Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Flavio Leitner <fbl@redhat.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 18:10:01 -08:00
Jiri Pirko
479840ffdb ipv6 addrconf: extend ifa_flags to u32
There is no more space in u8 ifa_flags. So do what davem suffested and
add another netlink attr called IFA_FLAGS for carry more flags.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 16:34:43 -05:00
David S. Miller
5d9efa7ee9 ipv6: Remove privacy config option.
The code for privacy extentions is very mature, and making it
configurable only gives marginal memory/code savings in exchange
for obfuscation and hard to read code via CPP ifdef'ery.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-28 20:07:50 -04:00
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
Hannes Frederic Sowa
b173ee488d ipv6: resend MLD report if a link-local address completes DAD
RFC3590/RFC3810 specifies we should resend MLD reports as soon as a
valid link-local address is available.

We now use the valid_ll_addr_cnt to check if it is necessary to resend
a new report.

Changes since Flavio Leitner's version:
a) adapt for valid_ll_addr_cnt
b) resend first reports directly in the path and just arm the timer for
   mc_qrv-1 resends.

Reported-by: Flavio Leitner <fleitner@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-28 21:19:17 -07:00
Hannes Frederic Sowa
1ec047eb47 ipv6: introduce per-interface counter for dad-completed ipv6 addresses
To reduce the number of unnecessary router solicitations, MLDv2 and IGMPv3
messages we need to track the number of valid (as in non-optimistic,
no-dad-failed and non-tentative) link-local addresses. Therefore, this
patch implements a valid_ll_addr_cnt in struct inet6_dev.

We now only emit router solicitations if the first link-local address
finishes duplicate address detection.

The changes for MLDv2 and IGMPv3 are in a follow-up patch.

While there, also simplify one if statement(one minor nit I made in one
of my previous patches):

if (!...)
	do();
else
	return;

<<into>>

if (...)
	return;
do();

Cc: Flavio Leitner <fbl@redhat.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Suggested-by: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-28 21:19:17 -07:00
Hannes Frederic Sowa
b7b1bfce0b ipv6: split duplicate address detection and router solicitation timer
This patch splits the timers for duplicate address detection and router
solicitations apart. The router solicitations timer goes into inet6_dev
and the dad timer stays in inet6_ifaddr.

The reason behind this patch is to reduce the number of unneeded router
solicitations send out by the host if additional link-local addresses
are created. Currently we send out RS for every link-local address on
an interface.

If the RS timer fires we pick a source address with ipv6_get_lladdr. This
change could hurt people adding additional link-local addresses and
specifying these addresses in the radvd clients section because we
no longer guarantee that we use every ll address as source address in
router solicitations.

Cc: Flavio Leitner <fleitner@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reviewed-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25 16:23:03 -07:00
Daniel Borkmann
168fc21a97 net: ipv6: remove 'next' member from inet6_dev
The next pointer within the inet6_dev structure seems not to be used
anywhere. So just remove it. Tested with allmodconfig on x86_64.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-20 13:49:48 -07:00
Nicolas Dichtel
caeaba7900 ipv6: add support of peer address
This patch adds the support of peer address for IPv6. For example, it is
possible to specify the remote end of a 6inY tunnel.
This was already possible in IPv4:
 ip addr add ip1 peer ip2 dev dev1

The peer address is specified with IFA_ADDRESS and the local address with
IFA_LOCAL (like explained in include/uapi/linux/if_addr.h).
Note that the API is not changed, because before this patch, it was not
possible to specify two different addresses in IFA_LOCAL and IFA_REMOTE.
There is a small change for the dump: if the peer is different from ::,
IFA_ADDRESS will contain the peer address instead of the local address.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-19 15:09:26 -07:00
Daniel Borkmann
617fe29d45 net: ipv6: only invalidate previously tokenized addresses
Instead of invalidating all IPv6 addresses with global scope
when one decides to use IPv6 tokens, we should only invalidate
previous tokens and leave the rest intact until they expire
eventually (or are intact forever). For doing this less greedy
approach, we're adding a bool at the end of inet6_ifaddr structure
instead, for two reasons: i) per-inet6_ifaddr flag space is
already used up, making it wider might not be a good idea,
since ii) also we do not necessarily need to export this
information into user space.

Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-09 13:12:23 -04:00
Daniel Borkmann
f53adae4ea net: ipv6: add tokenized interface identifier support
This patch adds support for IPv6 tokenized IIDs, that allow
for administrators to assign well-known host-part addresses
to nodes whilst still obtaining global network prefix from
Router Advertisements. It is currently in draft status.

  The primary target for such support is server platforms
  where addresses are usually manually configured, rather
  than using DHCPv6 or SLAAC. By using tokenised identifiers,
  hosts can still determine their network prefix by use of
  SLAAC, but more readily be automatically renumbered should
  their network prefix change. [...]

  The disadvantage with static addresses is that they are
  likely to require manual editing should the network prefix
  in use change.  If instead there were a method to only
  manually configure the static identifier part of the IPv6
  address, then the address could be automatically updated
  when a new prefix was introduced, as described in [RFC4192]
  for example.  In such cases a DNS server might be
  configured with such a tokenised interface identifier of
  ::53, and SLAAC would use the token in constructing the
  interface address, using the advertised prefix. [...]

  http://tools.ietf.org/html/draft-chown-6man-tokenised-ipv6-identifiers-02

The implementation is partially based on top of Mark K.
Thompson's proof of concept. However, it uses the Netlink
interface for configuration resp. data retrival, so that
it can be easily extended in future. Successfully tested
by myself.

Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-08 16:55:28 -04:00
Paul Gortmaker
211ed86510 net: delete all instances of special processing for token ring
We are going to delete the Token ring support.  This removes any
special processing in the core networking for token ring, (aside
from net/tr.c itself), leaving the drivers and remaining tokenring
support present but inert.

The mass removal of the drivers and net/tr.c will be in a separate
commit, so that the history of these files that we still care
about won't have the giant deletion tied into their history.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-05-15 20:14:35 -04:00
Eric Dumazet
95c9617472 net: cleanup unsigned to unsigned int
Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 12:44:40 -04:00
Lorenzo Colitti
76f793e3a4 ipv6: updates to privacy addresses per RFC 4941.
Update the code to handle some of the differences between
RFC 3041 and RFC 4941, which obsoletes it. Also a couple
of janitorial fixes.

- Allow router advertisements to increase the lifetime of
  temporary addresses. This was not allowed by RFC 3041,
  but is specified by RFC 4941. It is useful when RA
  lifetimes are lower than TEMP_{VALID,PREFERRED}_LIFETIME:
  in this case, the previous code would delete or deprecate
  addresses prematurely.

- Change the default of MAX_RETRY to 3 per RFC 4941.

- Add a comment to clarify that the preferred and valid
  lifetimes in inet6_ifaddr are relative to the timestamp.

- Shorten lines to 80 characters in a couple of places.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-08-01 18:05:00 -07:00
Eric Dumazet
be281e554e ipv6: reduce per device ICMP mib sizes
ipv6 has per device ICMP SNMP counters, taking too much space because
they use percpu storage.

needed size per device is :
(512+4)*sizeof(long)*number_of_possible_cpus*2

On a 32bit kernel, 16 possible cpus, this wastes more than 64kbytes of
memory per ipv6 enabled network device, taken in vmalloc pool.

Since ICMP messages are rare, just use shared counters (atomic_long_t)

Per network space ICMP counters are still using percpu memory, we might
also convert them to shared counters in a future patch.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-19 16:21:22 -04:00
David S. Miller
2a9e950701 net: Remove __KERNEL__ cpp checks from include/net
These header files are never installed to user consumption, so any
__KERNEL__ cpp checks are superfluous.

Projects should also not copy these files into their userland utility
sources and try to use them there.  If they insist on doing so, the
onus is on them to sanitize the headers as needed.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-24 10:54:56 -07:00
Eric Dumazet
b71d1d426d inet: constify ip headers and in6_addr
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-22 11:04:14 -07:00
Timo Teräs
93ca3bb5df net: gre: provide multicast mappings for ipv4 and ipv6
My commit 6d55cb91a0 (gre: fix hard header destination
address checking) broke multicast.

The reason is that ip_gre used to get ipgre_header() calls with
zero destination if we have NOARP or multicast destination. Instead
the actual target was decided at ipgre_tunnel_xmit() time based on
per-protocol dissection.

Instead of allowing the "abuse" of ->header() calls with invalid
destination, this creates multicast mappings for ip_gre. This also
fixes "ip neigh show nud noarp" to display the proper multicast
mappings used by the gre device.

Reported-by: Doug Kehn <rdkehn@yahoo.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Acked-by: Doug Kehn <rdkehn@yahoo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-30 00:10:47 -07:00
Eric Dumazet
456b61bca8 ipv6: mcast: RCU conversion
ipv6_sk_mc_lock rwlock becomes a spinlock.

readers (inet6_mc_check()) now takes rcu_read_lock() instead of read
lock. Writers dont need to disable BH anymore.

struct ipv6_mc_socklist objects are reclaimed after one RCU grace
period.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-24 11:16:42 -08:00
Herbert Xu
e9d3e08497 ipv6: Replace inet6_ifaddr->dead with state
This patch replaces the boolean dead flag on inet6_ifaddr with
a state enum.  This allows us to roll back changes when deleting
an address according to whether DAD has completed or not.

This patch only adds the state field and does not change the logic.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-18 15:36:06 -07:00
stephen hemminger
502a2ffd73 ipv6: convert idev_list to list macros
Convert to list macro's for the list of addresses per interface
in IPv6.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-20 15:45:09 -07:00
stephen hemminger
5c578aedcb IPv6: convert addrconf hash list to RCU
Convert from reader/writer lock to RCU and spinlock for addrconf
hash list.

Adds an additional helper macro for hlist_for_each_entry_continue_rcu
to handle the continue case.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-20 15:44:35 -07:00
stephen hemminger
c2e21293c0 ipv6: convert addrconf list to hlist
Using hash list macros, simplifies code and helps later RCU.

This patch includes some initialization that is not strictly necessary,
since an empty hlist node/list is all zero; and list is in BSS
and node is allocated with kzalloc.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-20 15:44:34 -07:00
stephen hemminger
372e6c8f1f ipv6: convert temporary address list to list macros
Use list macros instead of open coded linked list.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-20 15:44:34 -07:00
Stephen Hemminger
6457d26bd4 IPv6: convert mc_lock to spinlock
Only used for writing, so convert to spinlock

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-17 18:48:44 -08:00
Eric Dumazet
fd2c3ef761 net: cleanup include/net
This cleanup patch puts struct/union/enum opening braces,
in first line to ease grep games.

struct something
{

becomes :

struct something {

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-04 05:06:25 -08:00