xfrm: lwtunnel: add lwtunnel support for xfrm interfaces in collect_md mode

Allow specifying the xfrm interface if_id and link as part of a route
metadata using the lwtunnel infrastructure.

This allows for example using a single xfrm interface in collect_md
mode as the target of multiple routes each specifying a different if_id.

With the appropriate changes to iproute2, considering an xfrm device
ipsec1 in collect_md mode one can for example add a route specifying
an if_id like so:

ip route add <SUBNET> dev ipsec1 encap xfrm if_id 1

In which case traffic routed to the device via this route would use
if_id in the xfrm interface policy lookup.

Or in the context of vrf, one can also specify the "link" property:

ip route add <SUBNET> dev ipsec1 encap xfrm if_id 1 link_dev eth15

Note: LWT_XFRM_LINK uses NLA_U32 similar to IFLA_XFRM_LINK even though
internally "link" is signed. This is consistent with other _LINK
attributes in other devices as well as in bpf and should not have an
effect as device indexes can't be negative.

Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

ipv6: ioam: Support for IOAM injection with lwtunnels

Add support for the IOAM inline insertion (only for the host-to-host use case)
which is per-route configured with lightweight tunnels. The target is iproute2
and the patch is ready. It will be posted as soon as this patchset is merged.
Here is an overview:

$ ip -6 ro ad fc00::1/128 encap ioam6 trace type 0x800000 ns 1 size 12 dev eth0

This example configures an IOAM Pre-allocated Trace option attached to the
fc00::1/128 prefix. The IOAM namespace (ns) is 1, the size of the pre-allocated
trace data block is 12 octets (size) and only the first IOAM data (bit 0:
hop_limit + node id) is included in the trace (type) represented as a bitfield.

The reason why the in-transit (IPv6-in-IPv6 encapsulation) use case is not
implemented is explained on the patchset cover.

Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ipv6: add rpl sr tunnel

This patch adds functionality to configure routes for RPL source routing
functionality. There is no IPIP functionality yet implemented which can
be added later when the cases when to use IPv6 encapuslation comes more
clear.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lwtunnel: add options setting and dumping for erspan

Based on the code framework built on the last patch, to
support setting and dumping for vxlan, we only need to
add ip_tun_parse_opts_erspan() for .build_state and
ip_tun_fill_encap_opts_erspan() for .fill_encap and
if (tun_flags & TUNNEL_ERSPAN_OPT) for .get_encap_size.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lwtunnel: add options setting and dumping for vxlan

Based on the code framework built on the last patch, to
support setting and dumping for vxlan, we only need to
add ip_tun_parse_opts_vxlan() for .build_state and
ip_tun_fill_encap_opts_vxlan() for .fill_encap and
if (tun_flags & TUNNEL_VXLAN_OPT) for .get_encap_size.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lwtunnel: add options setting and dumping for geneve

To add options setting and dumping, .build_state(), .fill_encap() and
.get_encap_size() in ip_tun_lwt_ops needs to be extended:

ip_tun_build_state():
ip_tun_parse_opts():
ip_tun_parse_opts_geneve()

ip_tun_fill_encap_info():
ip_tun_fill_encap_opts():
ip_tun_fill_encap_opts_geneve()

ip_tun_encap_nlsize()
ip_tun_opts_nlsize():
if (tun_flags & TUNNEL_GENEVE_OPT)

ip_tun_parse_opts(), ip_tun_fill_encap_opts() and ip_tun_opts_nlsize()
processes LWTUNNEL_IP_OPTS.

ip_tun_parse_opts_geneve(), ip_tun_fill_encap_opts_geneve() and
if (tun_flags & TUNNEL_GENEVE_OPT) processes LWTUNNEL_IP_OPTS_GENEVE.

Signed-off-by: Xin Long <lucien.xin@gmail.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>

ipv6: sr: define core operations for seg6local lightweight tunnel

This patch implements a new type of lightweight tunnel named seg6local.
A seg6local lwt is defined by a type of action and a set of parameters.
The action represents the operation to perform on the packets matching the
lwt's route, and is not necessarily an encapsulation. The set of parameters
are arguments for the processing function.

Each action is defined in a struct seg6_action_desc within
seg6_action_table[]. This structure contains the action, mandatory
attributes, the processing function, and a static headroom size required by
the action. The mandatory attributes are encoded as a bitmask field. The
static headroom is set to a non-zero value when the processing function
always add a constant number of bytes to the skb (e.g. the header size for
encapsulations).

To facilitate rtnetlink-related operations such as parsing, fill_encap,
and cmp_encap, each type of action parameter is associated to three
function pointers, in seg6_action_params[].

All actions defined in seg6_local.h are detailed in [1].

[1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01

Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

bpf: BPF for lightweight tunnel infrastructure

Registers new BPF program types which correspond to the LWT hooks:
- BPF_PROG_TYPE_LWT_IN => dst_input()
- BPF_PROG_TYPE_LWT_OUT => dst_output()
- BPF_PROG_TYPE_LWT_XMIT => lwtunnel_xmit()

The separate program types are required to differentiate between the
capabilities each LWT hook allows:

* Programs attached to dst_input() or dst_output() are restricted and
may only read the data of an skb. This prevent modification and
possible invalidation of already validated packet headers on receive
and the construction of illegal headers while the IP headers are
still being assembled.

* Programs attached to lwtunnel_xmit() are allowed to modify packet
content as well as prepending an L2 header via a newly introduced
helper bpf_skb_change_head(). This is safe as lwtunnel_xmit() is
invoked after the IP header has been assembled completely.

All BPF programs receive an skb with L3 headers attached and may return
one of the following error codes:

BPF_OK - Continue routing as per nexthop
BPF_DROP - Drop skb and return EPERM
BPF_REDIRECT - Redirect skb to device as per redirect() helper.
(Only valid in lwtunnel_xmit() context)

The return codes are binary compatible with their TC_ACT_
relatives to ease compatibility.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipv6: sr: add support for SRH encapsulation and injection with lwtunnels

This patch creates a new type of interfaceless lightweight tunnel (SEG6),
enabling the encapsulation and injection of SRH within locally emitted
packets and forwarded packets.

>From a configuration viewpoint, a seg6 tunnel would be configured as follows:

ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 dev eth0

Any packet whose destination address is fc00::1 would thus be encapsulated
within an outer IPv6 header containing the SRH with three segments, and would
actually be routed to the first segment of the list. If `mode inline' was
specified instead of `mode encap', then the SRH would be directly inserted
after the IPv6 header without outer encapsulation.

The inline mode is only available if CONFIG_IPV6_SEG6_INLINE is enabled. This
feature was made configurable because direct header insertion may break
several mechanisms such as PMTUD or IPSec AH.

Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

libnl: nla_put_be64(): align on a 64-bit area

nla_data() is now aligned on a 64-bit area.

A temporary version (nla_put_be64_32bit()) is added for nla_put_net64().
This function is removed in the next patch.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lwtunnel: remove source and destination UDP port config option

The UDP tunnel config is asymmetric wrt. to the ports used. The source and
destination ports from one direction of the tunnel are not related to the
ports of the other direction. We need to be able to respond to ARP requests
using the correct ports without involving routing.

As the consequence, UDP ports need to be fixed property of the tunnel
interface and cannot be set per route. Remove the ability to set ports per
route. This is still okay to do, as no kernel has been released with these
attributes yet.

Note that the ability to specify source and destination ports is preserved
for other users of the lwtunnel API which don't use routes for tunnel key
specification (like openvswitch).

If in the future we rework ARP handling to allow port specification, the
attributes can be added back.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipv6: route: per route IP tunnel metadata via lightweight tunnel

Allow specification of per route IP tunnel instructions also for IPv6.
This complements commit 3093fbe7ff4b ("route: Per route IP tunnel metadata
via lightweight tunnel").

Signed-off-by: Jiri Benc <jbenc@redhat.com>
CC: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Identifier Locator Addressing module

Adding new module name ila. This implements ILA translation. Light
weight tunnel redirection is used to perform the translation in
the data path. This is configured by the "ip -6 route" command
using the "encap ila <locator>" option, where <locator> is the
value to set in destination locator of the packet. e.g.

ip -6 route add 3333:0:0:1:5555:0:1:0/128 \
encap ila 2001:0:0:1 via 2401:db00:20:911a:face:0:25:0

Sets a route where 3333:0:0:1 will be overwritten by
2001:0:0:1 on output.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lwtunnel: rename ip lwtunnel attributes

We already have IFLA_IPTUN_ netlink attributes. The IP_TUN_ attributes look
very similar, yet they serve very different purpose. This is confusing for
anyone trying to implement a user space tool supporting lwt.

As the IP_TUN_ attributes are used only for the lightweight tunnels, prefix
them with LWTUNNEL_IP_ instead to make their purpose clear. Also, it's more
logical to have them in lwtunnel.h together with the encap enum.

Fixes: 3093fbe7ff4b ("route: Per route IP tunnel metadata via lightweight tunnel")
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

route: Per route IP tunnel metadata via lightweight tunnel

This introduces a new IP tunnel lightweight tunnel type which allows
to specify IP tunnel instructions per route. Only IPv4 is supported
at this point.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

lwtunnel: infrastructure for handling light weight tunnels like mpls

Provides infrastructure to parse/dump/store encap information for
light weight tunnels like mpls. Encap information for such tunnels
is associated with fib routes.

This infrastructure is based on previous suggestions from
Eric Biederman to follow the xfrm infrastructure.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>