Move fib6_nh to the end of fib6_info and make it an array of
size 0. Pass a flag to fib6_info_alloc indicating if the
allocation needs to add space for a fib6_nh.

The current code path always has a fib6_nh allocated with a
fib6_info; with nexthop objects they will be separate.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Disabling IPv6 on an interface removes existing entries but nothing prevents
new entries from being manually added. To that end, add a new neigh_table
operation, allow_add, that is called on RTM_NEWNEIGH to see if neighbor
entries are allowed on a given device. If IPv6 is disabled on the device,
allow_add returns false and passes a message back to the user via extack.

  $ echo 1 > /proc/sys/net/ipv6/conf/eth1/disable_ipv6
  $ ip -6 neigh add fe80::4c88:bff:fe21:2704 dev eth1 lladdr de:ad:be:ef:01:01
  Error: IPv6 is disabled on this device.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename fib6_nh entries that will be moved to a fib_nh_common struct.
Specifically, the device, gateway, flags, and lwtstate are common
with all nexthop definitions. In some places new temporary variables
are declared or local variables renamed to maintain line lengths.

Rename only; no functional change intended.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit a61bbcf2 ("[NET]: Store skb->timestamp as offset to a base
timestamp") introduces a neighbour control buffer and zeroes it out in
ndisc_rcv(), as ndisc_recv_ns() uses it.

Commit f2776ff0 ("[IPV6]: Fix address/interface handling in UDP and
DCCP, according to the scoping architecture.") introduces the usage of the
IPv6 control buffer in protocol error handlers (e.g. inet6_iif() in
present-day __udp6_lib_err()).

Now, with commit b94f1c09 ("ipv6: Use icmpv6_notify() to propagate
redirect, instead of rt6_redirect()."), we call protocol error handlers
from ndisc_redirect_rcv(), after the control buffer is already stolen and
some parts are already zeroed out. This implies that inet6_iif() on this
path will always return zero.

This gives unexpected results on UDP socket lookup in __udp6_lib_err(), as
we might actually need to match sockets for a given interface.

Instead of always claiming the control buffer in ndisc_rcv(), do that only
when needed.

Fixes: b94f1c09 ("ipv6: Use icmpv6_notify() to propagate redirect, instead of rt6_redirect().")
Signed-off-by: NStefano Brivio <sbrivio@redhat.com>
Reviewed-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a link's carrier goes down it could be a sign of the port changing
networks. If the new network has overlapping addresses with the old one,
then the kernel will continue trying to use neighbor entries established
based on the old network until the entries finally age out - meaning a
potentially long delay with communications not working.

This patch evicts neighbor entries on carrier down with the exception of
those marked permanent. Permanent entries are managed by userspace (either
an admin or a routing daemon such as FRR).
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

(the parameter in question is mark)
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Reviewed-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit adc176c5 ("ipv6 addrconf: Implemented enhanced DAD (RFC7527)")
added enhanced DAD with a nonce length of 6 bytes. However, RFC7527
doesn't specify the length of the nonce, other than being 6 + 8*k bytes,
with integer k >= 0 (RFC3971 5.3.2). The current implementation simply
assumes that the nonce will always be 6 bytes, but others systems are
free to choose different sizes.

If another system sends a nonce of different length but with the same 6
bytes prefix, it shouldn't be considered as the same nonce. Thus, check
that the length of the received nonce is the same as the length we sent.

Ugly scapy test script running on veth0:

def loop():
    pkt=sniff(iface="veth0", filter="icmp6", count=1)
    pkt = pkt[0]
    b = bytearray(pkt[Raw].load)
    b[1] += 1
    b += b'\xde\xad\xbe\xef\xde\xad\xbe\xef'
    pkt[Raw].load = bytes(b)
    pkt[IPv6].plen += 8
    # fixup checksum after modifying the payload
    pkt[IPv6].payload.cksum -= 0x3b44
    if pkt[IPv6].payload.cksum < 0:
        pkt[IPv6].payload.cksum += 0xffff
    sendp(pkt, iface="veth0")

This should result in DAD failure for any address added to veth0's peer,
but is currently ignored.

Fixes: adc176c5 ("ipv6 addrconf: Implemented enhanced DAD (RFC7527)")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Reviewed-by: NStefano Brivio <sbrivio@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the right device to determine if redirect should be sent especially
when using vrf. Same as well as when sending the redirect.
Signed-off-by: NStephen Suryaputra <ssuryaextr@gmail.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change the prefix for fib6_info struct elements from rt6i_ to fib6_.
rt6i_pcpu and rt6i_exception_bucket are left as is given that they
point to rt6_info entries.

Rename only; not functional change intended.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert all code paths referencing a FIB entry from
rt6_info to fib6_info.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Last step before flipping the data type for FIB entries:
- use fib6_info_alloc to create FIB entries in ip6_route_info_create
  and addrconf_dst_alloc
- use fib6_info_release in place of dst_release, ip6_rt_put and
  rt6_release
- remove the dst_hold before calling __ip6_ins_rt or ip6_del_rt
- when purging routes, drop per-cpu routes
- replace inc and dec of rt6i_ref with fib6_info_hold and fib6_info_release
- use rt->from since it points to the FIB entry
- drop references to exception bucket, fib6_metrics and per-cpu from
  dst entries (those are relevant for fib entries only)
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The router discovery code has a FIB entry and wants to validate the
gateway has a neighbor entry. Refactor the existing dst_neigh_lookup
for IPv6 and create a new function that takes the gateway and device
and returns a neighbor entry. Use the new function in
ndisc_router_discovery to validate the gateway.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add expires to rt6_info for FIB entries, and add fib6 helpers to
manage it. Data path use of dst.expires remains.

The transition is fairly straightforward: when working with fib entries,
rt->dst.expires is just rt->expires, rt6_clean_expires is replaced with
fib6_clean_expires, rt6_set_expires becomes fib6_set_expires, and
rt6_check_expired becomes fib6_check_expired, where the fib6 versions
are added by this patch.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar to IPv4, add fib metrics to the fib struct, which at the moment
is rt6_info. Will be moved to fib6_info in a later patch. Copy metrics
into dst by reference using refcount.

To make the transition:
- add dst_metrics to rt6_info. Default to dst_default_metrics if no
  metrics are passed during route add. No need for a separate pmtu
  entry; it can reference the MTU slot in fib6_metrics

- ip6_convert_metrics allocates memory in the FIB entry and uses
  ip_metrics_convert to copy from netlink attribute to metrics entry

- the convert metrics call is done in ip6_route_info_create simplifying
  the route add path
  + fib6_commit_metrics and fib6_copy_metrics and the temporary
    mx6_config are no longer needed

- add fib6_metric_set helper to change the value of a metric in the
  fib entry since dst_metric_set can no longer be used

- cow_metrics for IPv6 can drop to dst_cow_metrics_generic

- rt6_dst_from_metrics_check is no longer needed

- rt6_fill_node needs the FIB entry and dst as separate arguments to
  keep compatibility with existing output. Current dst address is
  renamed to dest.
  (to be consistent with IPv4 rt6_fill_node really should be split
  into 2 functions similar to fib_dump_info and rt_fill_info)

- rt6_fill_node no longer needs the temporary metrics variable
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass network namespace reference into route add, delete and get
functions.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_chk_addr_and_flags determines if an address is a local address and
optionally if it is an address on a specific device. For example, it is
called by ip6_route_info_create to determine if a given gateway address
is a local address. The address check currently does not consider L3
domains and as a result does not allow a route to be added in one VRF
if the nexthop points to an address in a second VRF. e.g.,

    $ ip route add 2001:db8:1::/64 vrf r2 via 2001:db8:102::23
    Error: Invalid gateway address.

where 2001:db8:102::23 is an address on an interface in vrf r1.

ipv6_chk_addr_and_flags needs to allow callers to always pass in a device
with a separate argument to not limit the address to the specific device.
The device is used used to determine the L3 domain of interest.

To that end add an argument to skip the device check and update callers
to always pass a device where possible and use the new argument to mean
any address in the domain.

Update a handful of users of ipv6_chk_addr with a NULL dev argument. This
patch handles the change to these callers without adding the domain check.

ip6_validate_gw needs to handle 2 cases - one where the device is given
as part of the nexthop spec and the other where the device is resolved.
There is at least 1 VRF case where deferring the check to only after
the route lookup has resolved the device fails with an unintuitive error
"RTNETLINK answers: No route to host" as opposed to the preferred
"Error: Gateway can not be a local address." The 'no route to host'
error is because of the fallback to a full lookup. The check is done
twice to avoid this error.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the following slab-out-of-bounds kasan report in
ndisc_fill_redirect_hdr_option when the incoming ipv6 packet is not
linear and the accessed data are not in the linear data region of orig_skb.

[ 1503.122508] ==================================================================
[ 1503.122832] BUG: KASAN: slab-out-of-bounds in ndisc_send_redirect+0x94e/0x990
[ 1503.123036] Read of size 1184 at addr ffff8800298ab6b0 by task netperf/1932

[ 1503.123220] CPU: 0 PID: 1932 Comm: netperf Not tainted 4.16.0-rc2+ #124
[ 1503.123347] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-2.fc27 04/01/2014
[ 1503.123527] Call Trace:
[ 1503.123579]  <IRQ>
[ 1503.123638]  print_address_description+0x6e/0x280
[ 1503.123849]  kasan_report+0x233/0x350
[ 1503.123946]  memcpy+0x1f/0x50
[ 1503.124037]  ndisc_send_redirect+0x94e/0x990
[ 1503.125150]  ip6_forward+0x1242/0x13b0
[...]
[ 1503.153890] Allocated by task 1932:
[ 1503.153982]  kasan_kmalloc+0x9f/0xd0
[ 1503.154074]  __kmalloc_track_caller+0xb5/0x160
[ 1503.154198]  __kmalloc_reserve.isra.41+0x24/0x70
[ 1503.154324]  __alloc_skb+0x130/0x3e0
[ 1503.154415]  sctp_packet_transmit+0x21a/0x1810
[ 1503.154533]  sctp_outq_flush+0xc14/0x1db0
[ 1503.154624]  sctp_do_sm+0x34e/0x2740
[ 1503.154715]  sctp_primitive_SEND+0x57/0x70
[ 1503.154807]  sctp_sendmsg+0xaa6/0x1b10
[ 1503.154897]  sock_sendmsg+0x68/0x80
[ 1503.154987]  ___sys_sendmsg+0x431/0x4b0
[ 1503.155078]  __sys_sendmsg+0xa4/0x130
[ 1503.155168]  do_syscall_64+0x171/0x3f0
[ 1503.155259]  entry_SYSCALL_64_after_hwframe+0x42/0xb7

[ 1503.155436] Freed by task 1932:
[ 1503.155527]  __kasan_slab_free+0x134/0x180
[ 1503.155618]  kfree+0xbc/0x180
[ 1503.155709]  skb_release_data+0x27f/0x2c0
[ 1503.155800]  consume_skb+0x94/0xe0
[ 1503.155889]  sctp_chunk_put+0x1aa/0x1f0
[ 1503.155979]  sctp_inq_pop+0x2f8/0x6e0
[ 1503.156070]  sctp_assoc_bh_rcv+0x6a/0x230
[ 1503.156164]  sctp_inq_push+0x117/0x150
[ 1503.156255]  sctp_backlog_rcv+0xdf/0x4a0
[ 1503.156346]  __release_sock+0x142/0x250
[ 1503.156436]  release_sock+0x80/0x180
[ 1503.156526]  sctp_sendmsg+0xbb0/0x1b10
[ 1503.156617]  sock_sendmsg+0x68/0x80
[ 1503.156708]  ___sys_sendmsg+0x431/0x4b0
[ 1503.156799]  __sys_sendmsg+0xa4/0x130
[ 1503.156889]  do_syscall_64+0x171/0x3f0
[ 1503.156980]  entry_SYSCALL_64_after_hwframe+0x42/0xb7

[ 1503.157158] The buggy address belongs to the object at ffff8800298ab600
                which belongs to the cache kmalloc-1024 of size 1024
[ 1503.157444] The buggy address is located 176 bytes inside of
                1024-byte region [ffff8800298ab600, ffff8800298aba00)
[ 1503.157702] The buggy address belongs to the page:
[ 1503.157820] page:ffffea0000a62a00 count:1 mapcount:0 mapping:0000000000000000 index:0x0 compound_mapcount: 0
[ 1503.158053] flags: 0x4000000000008100(slab|head)
[ 1503.158171] raw: 4000000000008100 0000000000000000 0000000000000000 00000001800e000e
[ 1503.158350] raw: dead000000000100 dead000000000200 ffff880036002600 0000000000000000
[ 1503.158523] page dumped because: kasan: bad access detected

[ 1503.158698] Memory state around the buggy address:
[ 1503.158816]  ffff8800298ab900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 1503.158988]  ffff8800298ab980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 1503.159165] >ffff8800298aba00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 1503.159338]                    ^
[ 1503.159436]  ffff8800298aba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 1503.159610]  ffff8800298abb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 1503.159785] ==================================================================
[ 1503.159964] Disabling lock debugging due to kernel taint

The test scenario to trigger the issue consists of 4 devices:
- H0: data sender, connected to LAN0
- H1: data receiver, connected to LAN1
- GW0 and GW1: routers between LAN0 and LAN1. Both of them have an
  ethernet connection on LAN0 and LAN1
On H{0,1} set GW0 as default gateway while on GW0 set GW1 as next hop for
data from LAN0 to LAN1.
Moreover create an ip6ip6 tunnel between H0 and H1 and send 3 concurrent
data streams (TCP/UDP/SCTP) from H0 to H1 through ip6ip6 tunnel (send
buffer size is set to 16K). While data streams are active flush the route
cache on HA multiple times.
I have not been able to identify a given commit that introduced the issue
since, using the reproducer described above, the kasan report has been
triggered from 4.14 and I have not gone back further.
Reported-by: NJianlin Shi <jishi@redhat.com>
Reviewed-by: NStefano Brivio <sbrivio@redhat.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Assign true or false to boolean variables instead of an integer value.

This issue was detected with the help of Coccinelle.
Signed-off-by: NGustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These pernet_operations create and destroy net::ipv6.icmp_sk
socket, used to send ICMP or error reply.

Nobody can dereference the socket to handle a packet before
net is initialized, as there is no routing; nobody can do
that in parallel with exit, as all of devices are moved
to init_net or destroyed and there are no packets it-flight.
So, it's possible to mark these pernet_operations as async.

The same for ndisc_net_ops and for igmp6_net_ops. The last
one also creates and destroys /proc entries.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Unsolicited IPv6 neighbor advertisements should be sent after DAD
completes. Update ndisc_send_unsol_na to skip tentative, non-optimistic
addresses and have those sent by addrconf_dad_completed after DAD.

Fixes: 4a6e3c5d ("net: ipv6: send unsolicited NA on admin up")
Reported-by: NVivek Venkatraman <vivek@cumulusnetworks.com>
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a per-device sysctl to specify the default traffic class to use for
kernel originated IPv6 Neighbour Discovery packets.

Currently this includes:

  - Router Solicitation (ICMPv6 type 133)
    ndisc_send_rs() -> ndisc_send_skb() -> ip6_nd_hdr()

  - Neighbour Solicitation (ICMPv6 type 135)
    ndisc_send_ns() -> ndisc_send_skb() -> ip6_nd_hdr()

  - Neighbour Advertisement (ICMPv6 type 136)
    ndisc_send_na() -> ndisc_send_skb() -> ip6_nd_hdr()

  - Redirect (ICMPv6 type 137)
    ndisc_send_redirect() -> ndisc_send_skb() -> ip6_nd_hdr()

and if the kernel ever gets around to generating RA's,
it would presumably also include:

  - Router Advertisement (ICMPv6 type 134)
    (radvd daemon could pick up on the kernel setting and use it)

Interface drivers may examine the Traffic Class value and translate
the DiffServ Code Point into a link-layer appropriate traffic
prioritization scheme.  An example of mapping IETF DSCP values to
IEEE 802.11 User Priority values can be found here:

    https://tools.ietf.org/html/draft-ietf-tsvwg-ieee-802-11

The expected primary use case is to properly prioritize ND over wifi.

Testing:
  jzem22:~# cat /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  0
  jzem22:~# echo -1 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  -bash: echo: write error: Invalid argument
  jzem22:~# echo 256 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  -bash: echo: write error: Invalid argument
  jzem22:~# echo 0 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  jzem22:~# echo 255 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  jzem22:~# cat /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  255
  jzem22:~# echo 34 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  jzem22:~# cat /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  34

  jzem22:~# echo $[0xDC] > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
  jzem22:~# tcpdump -v -i eth0 icmp6 and src host jzem22.pgc and dst host fe80::1
  tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
  IP6 (class 0xdc, hlim 255, next-header ICMPv6 (58) payload length: 24)
  jzem22.pgc > fe80::1: [icmp6 sum ok] ICMP6, neighbor advertisement,
  length 24, tgt is jzem22.pgc, Flags [solicited]

(based on original change written by Erik Kline, with minor changes)

v2: fix 'suspicious rcu_dereference_check() usage'
    by explicitly grabbing the rcu_read_lock.

Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: NErik Kline <ek@google.com>
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch updates the error messages displayed in kernel log to include
hwaddress of the source machine that caused ipv6 duplicate address
detection failures.

Examples:

a) When we receive a NA packet from another machine advertising our
address:

ICMPv6: NA: 34:ab:cd:56:11:e8 advertised our address 2001:db8:: on eth0!

b) When we detect DAD failure during address assignment to an interface:

IPv6: eth0: IPv6 duplicate address 2001:db8:: used by 34:ab:cd:56:11:e8
detected!

v2:
    Changed %pI6 to %pI6c in ndisc_recv_na()
    Chaged the v6 address in the commit message to 2001:db8::
Suggested-by: NIgor Lubashev <ilubashe@akamai.com>
Signed-off-by: NVishwanath Pai <vpai@akamai.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Florian reported UDP xmit drops that could be root caused to the
too small neigh limit.

Current limit is 64 KB, meaning that even a single UDP socket would hit
it, since its default sk_sndbuf comes from net.core.wmem_default
(~212992 bytes on 64bit arches).

Once ARP/ND resolution is in progress, we should allow a little more
packets to be queued, at least for one producer.

Once neigh arp_queue is filled, a rogue socket should hit its sk_sndbuf
limit and either block in sendmsg() or return -EAGAIN.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ndisc_notify is used to send unsolicited neighbor advertisements
(e.g., on a link up). Currently, the ndisc notifier is run before the
addrconf notifer which means NA's are not sent for link-local addresses
which are added by the addrconf notifier.

Fix by lowering the priority of the ndisc notifier. Setting the priority
to ADDRCONF_NOTIFY_PRIORITY - 5 means it runs after addrconf and before
the route notifier which is ADDRCONF_NOTIFY_PRIORITY - 10.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When arp_notify is set to 1 for either a specific interface or for 'all'
interfaces, gratuitous arp requests are sent. Since ndisc_notify is the
ipv6 equivalent to arp_notify, it should follow the same semantics.
Commit 4a6e3c5d ("net: ipv6: send unsolicited NA on admin up") sends
the NA on admin up. The final piece is checking devconf_all->ndisc_notify
in addition to the per device setting. Add it.

Fixes: 5cb04436 ("ipv6: add knob to send unsolicited ND on link-layer address change")
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ndisc_notify is the ipv6 equivalent to arp_notify. When arp_notify is
set to 1, gratuitous arp requests are sent when the device is brought up.
The same is expected when ndisc_notify is set to 1 (per ndisc_notify in
Documentation/networking/ip-sysctl.txt). The NA is not sent on NETDEV_UP
event; add it.

Fixes: 5cb04436 ("ipv6: add knob to send unsolicited ND on link-layer address change")
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit adds a new sysctl accept_ra_rt_info_min_plen that
defines the minimum acceptable prefix length of Route Information
Options. The new sysctl is intended to be used together with
accept_ra_rt_info_max_plen to configure a range of acceptable
prefix lengths. It is useful to prevent misconfigurations from
unintentionally blackholing too much of the IPv6 address space
(e.g., home routers announcing RIOs for fc00::/7, which is
incorrect).
Signed-off-by: NJoel Scherpelz <jscherpelz@google.com>
Acked-by: NLorenzo Colitti <lorenzo@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

neigh notifications today carry pid 0 for nlmsg_pid
in all cases. This patch fixes it to carry calling process
pid when available. Applications (eg. quagga) rely on
nlmsg_pid to ignore notifications generated by their own
netlink operations. This patch follows the routing subsystem
which already sets this correctly.
Reported-by: NVivek Venkatraman <vivek@cumulusnetworks.com>
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NErik Nordmark <nordmark@arista.com>
Signed-off-by: NBob Gilligan <gilligan@arista.com>
Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A previous patch added l3mdev flow update making these hooks
redundant. Remove them.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch exports some neighbour discovery functions which can be used
by 6lowpan neighbour discovery ops functionality then.

Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces neighbour discovery ops callback structure. The
idea is to separate the handling for 6LoWPAN into the 6lowpan module.

These callback offers 6lowpan different handling, such as 802.15.4 short
address handling or RFC6775 (Neighbor Discovery Optimization for IPv6
over 6LoWPANs).

Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds __ndisc_fill_addr_option as low-level function for
ndisc_fill_addr_option which doesn't depend on net_device parameter.

Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In certain 802.11 wireless deployments, there will be NA proxies
that use knowledge of the network to correctly answer requests.
To prevent unsolicitd advertisements on the shared medium from
being a problem, on such deployments wireless needs to drop them.

Enable this by providing an option called "drop_unsolicited_na".
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Marc Haber reported we don't honor interface indexes when we receive link
local router addresses in router advertisements. Luckily the non-strict
version of ipv6_chk_addr already does the correct job here, so we can
simply use it to lighten the checks and use those addresses by default
without any configuration change.

Link: <http://permalink.gmane.org/gmane.linux.network/391348>
Reported-by: NMarc Haber <mh+netdev@zugschlus.de>
Cc: Marc Haber <mh+netdev@zugschlus.de>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit ab450605.

In IPv6, we cannot inherit the dst of the original dst. ndisc packets
are IPv6 packets and may take another route than the original packet.

This patch breaks the following scenario: a packet comes from eth0 and
is forwarded through vxlan1. The encapsulated packet triggers an NS
which cannot be sent because of the wrong route.

CC: Jiri Benc <jbenc@redhat.com>
CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As with IPv4 support for VRFs added to IPv6 stack by replacing hardcoded
table ids with possibly device specific ones and manipulating the oif in
the flowi6. The flow flags are used to skip oif compare in nexthop lookups
if the device is enslaved to a VRF via the L3 master device.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>