More recent GCC warns about two kinds of switch statement uses:

1) Switching on an enumeration, but not having an explicit case
   statement for all members of the enumeration.  To show the
   compiler this is intentional, we simply add a default case
   with nothing more than a break statement.

2) Switching on a boolean value.  I think this warning is dumb
   but nevertheless you get it wholesale with -Wswitch.

This patch cures all such warnings in netfilter.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NPablo Neira Ayuso <pablo@netfilter.org>

Fixes: 79b16aad ("udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().")
Reported-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

right now we store this in the nf_bridge_info struct, accessible
via skb->nf_bridge.  This patch prepares removal of this pointer from skb:

Instead of using skb->nf_bridge->x, we use helpers to obtain the in/out
device (or ifindexes).

Followup patches to netfilter will then allow nf_bridge_info to be
obtained by a call into the br_netfilter core, rather than keeping a
pointer to it in sk_buff.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Signed-off-by: NSheng Yong <shengyong1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That was we can make sure the output path of ipv4/ipv6 operate on
the UDP socket rather than whatever random thing happens to be in
skb->sk.

Based upon a patch by Jiri Pirko.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>

On the output paths in particular, we have to sometimes deal with two
socket contexts.  First, and usually skb->sk, is the local socket that
generated the frame.

And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.

We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.

The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device.  We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We should not consult skb->sk for output decisions in xmit recursion
levels > 0 in the stack. Otherwise local socket settings could influence
the result of e.g. tunnel encapsulation process.

ipv6 does not conform with this in three places:

1) ip6_fragment: we do consult ipv6_npinfo for frag_size

2) sk_mc_loop in ipv6 uses skb->sk and checks if we should
   loop the packet back to the local socket

3) ip6_skb_dst_mtu could query the settings from the user socket and
   force a wrong MTU

Furthermore:
In sk_mc_loop we could potentially land in WARN_ON(1) if we use a
PF_PACKET socket ontop of an IPv6-backed vxlan device.

Reuse xmit_recursion as we are currently only interested in protecting
tunnel devices.

Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the nf_hook_state all the way down into the hook
functions themselves.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That way we don't have to reinstantiate another nf_hook_state
on the stack of the nf_reinject() path.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to wait for the flying timers, since we
are going to free the mrtable right after it.

Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have to hold rtnl lock for fib_rules_unregister()
otherwise the following race could happen:

fib_rules_unregister():	fib_nl_delrule():
...				...
...				ops = lookup_rules_ops();
list_del_rcu(&ops->list);
				list_for_each_entry(ops->rules) {
fib_rules_cleanup_ops(ops);	  ...
  list_del_rcu();		  list_del_rcu();
				}

Note, net->rules_mod_lock is actually not needed at all,
either upper layer netns code or rtnl lock guarantees
we are safe.

Cc: Alexander Duyck <alexander.h.duyck@redhat.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't use dev->iflink anymore.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't use dev->iflink anymore.

CC: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't use dev->iflink anymore.

CC: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The goal of this patch is to prepare the removal of the iflink field. It
introduces a new ndo function, which will be implemented by virtual interfaces.

There is no functional change into this patch. All readers of iflink field
now call dev_get_iflink().
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Those are counterparts to nla_put_in_addr and nla_put_in6_addr.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IP addresses are often stored in netlink attributes. Add generic functions
to do that.

For nla_put_in_addr, it would be nicer to pass struct in_addr but this is
not used universally throughout the kernel, in way too many places __be32 is
used to store IPv4 address.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In many places, the a6 field is typecasted to struct in6_addr. As the
fields are in union anyway, just add in6_addr type to the union and
get rid of the typecasting.

Modifying the uapi header is okay, the union has still the same size.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x != NULL and sometimes as x. x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.

No changes detected by objdiff.
Signed-off-by: NIan Morris <ipm@chirality.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x == NULL and sometimes as !x. !x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.

No changes detected by objdiff.
Signed-off-by: NIan Morris <ipm@chirality.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcp_v6_fill_cb() will be called twice if socket's state changes from
TCP_TIME_WAIT to TCP_LISTEN. That can result in control buffer data
corruption because in the second tcp_v6_fill_cb() call it's not copying
IP6CB(skb) anymore, but 'seq', 'end_seq', etc., so we can get weird and
unpredictable results. Performance loss of up to 1200% has been observed
in LTP/vxlan03 test.

This can be fixed by copying inet6_skb_parm to the beginning of 'cb'
only if xfrm6_policy_check() and tcp_v6_fill_cb() are going to be
called again.

Fixes: 2dc49d16 ("tcp6: don't move IP6CB before xfrm6_policy_check()")
Signed-off-by: NAlexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We should not commit the new ops until we finish
all the setup, otherwise we have to NULL it on failure.
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As namespaces are sometimes used with overlapping ip address ranges,
we should also use the namespace as input to the hash to select the ip
fragmentation counter bucket.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A local route may have a lower hop_limit set than global routes do.

RFC 3756, Section 4.2.7, "Parameter Spoofing"

>   1.  The attacker includes a Current Hop Limit of one or another small
>       number which the attacker knows will cause legitimate packets to
>       be dropped before they reach their destination.

>   As an example, one possible approach to mitigate this threat is to
>   ignore very small hop limits.  The nodes could implement a
>   configurable minimum hop limit, and ignore attempts to set it below
>   said limit.
Signed-off-by: ND.S. Ljungmark <ljungmark@modio.se>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the #defines where appropriate.

Miscellanea:

Add explicit #include <linux/kernel.h> where it was not
previously used so that these #defines are a bit more
explicitly defined instead of indirectly included via:
	module.h->moduleparam.h->kernel.h
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

ss should display ipv4 mapped request sockets like this :

tcp    SYN-RECV   0      0  ::ffff:192.168.0.1:8080   ::ffff:192.0.2.1:35261

and not like this :

tcp    SYN-RECV   0      0  192.168.0.1:8080   192.0.2.1:35261

We should init ireq->ireq_family based on listener sk_family,
not the actual protocol carried by SYN packet.

This means we can set ireq_family in inet_reqsk_alloc()

Fixes: 3f66b083 ("inet: introduce ireq_family")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With request socks convergence, we no longer need
different lookup methods. A request socket can
use generic lookup function.

Add const qualifier to 2nd tcp_v[46]_md5_lookup() parameter.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since request and established sockets now have same base,
there is no need to pass two pointers to tcp_v4_md5_hash_skb()
or tcp_v6_md5_hash_skb()

Also add a const qualifier to their struct tcp_md5sig_key argument.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is guaranteed that both tcp_v4_rcv() and tcp_v6_rcv()
run from rcu read locked sections :

ip_local_deliver_finish() and ip6_input_finish() both
use rcu_read_lock()

Also align tcp_v6_inbound_md5_hash() on tcp_v4_inbound_md5_hash()
by returning a boolean.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Those warnings reported by sparse endianness check (via kbuild test robot)
are harmless, nevertheless fix them up and make the code a little bit
easier to read.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Fixes: 622c81d5 ("ipv6: generation of stable privacy addresses for link-local and autoconf")
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On s390x, gcc 4.8 compiles this part of tcp_v6_early_demux()

        struct dst_entry *dst = sk->sk_rx_dst;

        if (dst)
                dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);

to code reading sk->sk_rx_dst twice, once for the test and once for
the argument of ip6_dst_check() (dst_check() is inline). This allows
ip6_dst_check() to be called with null first argument, causing a crash.

Protect sk->sk_rx_dst access by READ_ONCE() both in IPv4 and IPv6
TCP early demux code.

Fixes: 41063e9d ("ipv4: Early TCP socket demux.")
Fixes: c7109986 ("ipv6: Early TCP socket demux")
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is specified by RFC 7217.

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: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to mark appropriate addresses so we can do retries in case their
DAD failed.

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: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements the stable privacy address generation for
link-local and autoconf addresses as specified in RFC7217.

  RID = F(Prefix, Net_Iface, Network_ID, DAD_Counter, secret_key)

is the RID (random identifier). As the hash function F we chose one
round of sha1. Prefix will be either the link-local prefix or the
router advertised one. As Net_Iface we use the MAC address of the
device. DAD_Counter and secret_key are implemented as specified.

We don't use Network_ID, as it couples the code too closely to other
subsystems. It is specified as optional in the RFC.

As Net_Iface we only use the MAC address: we simply have no stable
identifier in the kernel we could possibly use: because this code might
run very early, we cannot depend on names, as they might be changed by
user space early on during the boot process.

A new address generation mode is introduced,
IN6_ADDR_GEN_MODE_STABLE_PRIVACY. With iproute2 one can switch back to
none or eui64 address configuration mode although the stable_secret is
already set.

We refuse writes to ipv6/conf/all/stable_secret but only allow
ipv6/conf/default/stable_secret and the interface specific file to be
written to. The default stable_secret is used as the parameter for the
namespace, the interface specific can overwrite the secret, e.g. when
switching a network configuration from one system to another while
inheriting the secret.

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: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>