net: ip6mr: add support for passing full packet on wrong mif

This patch adds support for MRT6MSG_WRMIFWHOLE which is used to pass
full packet and real vif id when the incoming interface is wrong.
While the RP and FHR are setting up state we need to be sending the
registers encapsulated with all the data inside otherwise we lose it.
The RP then decapsulates it and forwards it to the interested parties.
Currently with WRONGMIF we can only be sending empty register packets
and will lose that data.
This behaviour can be enabled by using MRT_PIM with
val == MRT6MSG_WRMIFWHOLE. This doesn't prevent MRT6MSG_WRONGMIF from
happening, it happens in addition to it, also it is controlled by the same
throttling parameters as WRONGMIF (i.e. 1 packet per 3 seconds currently).
Both messages are generated to keep backwards compatibily and avoid
breaking someone who was enabling MRT_PIM with val == 4, since any
positive val is accepted and treated the same.

Signed-off-by: Mobashshera Rasool <mobash.rasool.linux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

uapi: move constants from <linux/kernel.h> to <linux/const.h>

and include <linux/const.h> in UAPI headers instead of <linux/kernel.h>.

The reason is to avoid indirect <linux/sysinfo.h> include when using
some network headers: <linux/netlink.h> or others -> <linux/kernel.h>
-> <linux/sysinfo.h>.

This indirect include causes on MUSL redefinition of struct sysinfo when
included both <sys/sysinfo.h> and some of UAPI headers:

In file included from x86_64-buildroot-linux-musl/sysroot/usr/include/linux/kernel.h:5,
from x86_64-buildroot-linux-musl/sysroot/usr/include/linux/netlink.h:5,
from ../include/tst_netlink.h:14,
from tst_crypto.c:13:
x86_64-buildroot-linux-musl/sysroot/usr/include/linux/sysinfo.h:8:8: error: redefinition of `struct sysinfo'
struct sysinfo {
^~~~~~~
In file included from ../include/tst_safe_macros.h:15,
from ../include/tst_test.h:93,
from tst_crypto.c:11:
x86_64-buildroot-linux-musl/sysroot/usr/include/sys/sysinfo.h:10:8: note: originally defined here

Link: https://lkml.kernel.org/r/20201015190013.8901-1-petr.vorel@gmail.com
Signed-off-by: Petr Vorel <petr.vorel@gmail.com>
Suggested-by: Rich Felker <dalias@aerifal.cx>
Acked-by: Rich Felker <dalias@libc.org>
Cc: Peter Korsgaard <peter@korsgaard.com>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipmr: ip6mr: Create new sockopt to clear mfc cache or vifs

Currently the only way to clear the forwarding cache was to delete the
entries one by one using the MRT_DEL_MFC socket option or to destroy and
recreate the socket.

Create a new socket option which with the use of optional flags can
clear any combination of multicast entries (static or not static) and
multicast vifs (static or not static).

Calling the new socket option MRT_FLUSH with the flags MRT_FLUSH_MFC and
MRT_FLUSH_VIFS will clear all entries and vifs on the socket except for
static entries.

Signed-off-by: Callum Sinclair <callum.sinclair@alliedtelesis.co.nz>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

License cleanup: add SPDX license identifier to uapi header files with no license

Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.

By default are files without license information under the default
license of the kernel, which is GPLV2. Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:

NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".

otherwise syscall usage would not be possible.

Update the files which contain no license information with an SPDX
license identifier. The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception. SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne. See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ip6mr: add netlink notifications on mrt6msg cache reports

Add Netlink notifications on cache reports in ip6mr, in addition to the
existing mrt6msg sent to mroute6_sk.
Send RTM_NEWCACHEREPORT notifications to RTNLGRP_IPV6_MROUTE_R.

MSGTYPE, MIF_ID, SRC_ADDR and DST_ADDR Netlink attributes contain the
same data as their equivalent fields in the mrt6msg header.
PKT attribute is the packet sent to mroute6_sk, without the added
mrt6msg header.

Suggested-by: Ryan Halbrook <halbrook@arista.com>
Signed-off-by: Julien Gomes <julien@arista.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

uapi: fix linux/mroute6.h userspace compilation errors

Include <linux/in6.h> to fix the following linux/mroute6.h userspace
compilation errors:

/usr/include/linux/mroute6.h:80:22: error: field 'mf6cc_origin' has incomplete type
struct sockaddr_in6 mf6cc_origin; /* Origin of mcast */
/usr/include/linux/mroute6.h:81:22: error: field 'mf6cc_mcastgrp' has incomplete type
struct sockaddr_in6 mf6cc_mcastgrp; /* Group in question */
/usr/include/linux/mroute6.h:91:22: error: field 'src' has incomplete type
struct sockaddr_in6 src;
/usr/include/linux/mroute6.h:92:22: error: field 'grp' has incomplete type
struct sockaddr_in6 grp;
/usr/include/linux/mroute6.h:132:18: error: field 'im6_src' has incomplete type
struct in6_addr im6_src, im6_dst;
/usr/include/linux/mroute6.h:132:27: error: field 'im6_dst' has incomplete type
struct in6_addr im6_src, im6_dst;

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

uapi: define DIV_ROUND_UP for userland

DIV_ROUND_UP is defined in linux/kernel.h only for the kernel.
When ethtool.h is included by a userland app, we got the following error:

include/linux/ethtool.h:1218:8: error: variably modified 'queue_mask' at file scope
__u32 queue_mask[DIV_ROUND_UP(MAX_NUM_QUEUE, 32)];
^

Let's add a common definition in uapi and use it everywhere.

Fixes: ac2c7ad0e5d6 ("net/ethtool: introduce a new ioctl for per queue setting")
CC: Kan Liang <kan.liang@intel.com>
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mcast: add multicast proxy support (IPv4 and IPv6)

This patch add the support of proxy multicast, ie being able to build a static
multicast tree. It adds the support of (*,*) and (*,G) entries.

The user should define an (*,*) entry which is not used for real forwarding.
This entry defines the upstream in iif and contains all interfaces from the
static tree in its oifs. It will be used to forward packet upstream when they
come from an interface belonging to the static tree.
Hence, the user should define (*,G) entries to build its static tree. Note that
upstream interface must be part of oifs: packets are sent to all oifs
interfaces except the input interface. This ensures to always join the whole
static tree, even if the packet is not coming from the upstream interface.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mcast: define and use MRT[6]_MAX in ip[6]_mroute_opt()

This will ease further addition of new MRT[6]_* values and avoid to update
in6.h each time.
Note that we reduce the maximum value from 210 to 209, but 210 does not match
any known value in ip[6]_mroute_setsockopt().

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>