netfilter: flowtable: validate pppoe header

Ensure there is sufficient room to access the protocol field of the
PPPoe header. Validate it once before the flowtable lookup, then use a
helper function to access protocol field.

Reported-by: syzbot+b6f07e1c07ef40199081@syzkaller.appspotmail.com
Fixes: 72efd585f714 ("netfilter: flowtable: add pppoe support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: flowtable: cache info of last offload

Modify flow table offload to cache the last ct info status that was passed
to the driver offload callbacks by extending enum nf_flow_flags with new
"NF_FLOW_HW_ESTABLISHED" flag. Set the flag if ctinfo was 'established'
during last act_ct meta actions fill call. This infrastructure change is
necessary to optimize promoting of UDP connections from 'new' to
'established' in following patches in this series.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: flowtable: Fix QinQ and pppoe support for inet table

nf_flow_offload_inet_hook() does not check for 802.1q and PPPoE.
Fetch inner ethertype from these encapsulation protocols.

Fixes: 72efd585f714 ("netfilter: flowtable: add pppoe support")
Fixes: 4cd91f7c290f ("netfilter: flowtable: add vlan support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: flowtable: remove ipv4/ipv6 modules

Just place the structs and registration in the inet module.
nf_flow_table_ipv6, nf_flow_table_ipv4 and nf_flow_table_inet share
same module dependencies: nf_flow_table, nf_tables.

before:
text data bss dec hex filename
2278 1480 0 3758 eae nf_flow_table_inet.ko
1159 1352 0 2511 9cf nf_flow_table_ipv6.ko
1154 1352 0 2506 9ca nf_flow_table_ipv4.ko

after:
2369 1672 0 4041 fc9 nf_flow_table_inet.ko

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Add MODULE_DESCRIPTION entries to kernel modules

The user tool modinfo is used to get information on kernel modules, including a
description where it is available.

This patch adds a brief MODULE_DESCRIPTION to netfilter kernel modules
(descriptions taken from Kconfig file or code comments)

Signed-off-by: Rob Gill <rrobgill@protonmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_flow_table_offload: add IPv6 support

Add nf_flow_rule_route_ipv6() and use it from the IPv6 and the inet
flowtable type definitions. Rename the nf_flow_rule_route() function to
nf_flow_rule_route_ipv4().

Adjust maximum number of actions, which now becomes 16 to leave
sufficient room for the IPv6 address mangling for NAT.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_flow_table: hardware offload support

This patch adds the dataplane hardware offload to the flowtable
infrastructure. Three new flags represent the hardware state of this
flow:

* FLOW_OFFLOAD_HW: This flow entry resides in the hardware.
* FLOW_OFFLOAD_HW_DYING: This flow entry has been scheduled to be remove
from hardware. This might be triggered by either packet path (via TCP
RST/FIN packet) or via aging.
* FLOW_OFFLOAD_HW_DEAD: This flow entry has been already removed from
the hardware, the software garbage collector can remove it from the
software flowtable.

This patch supports for:

* IPv4 only.
* Aging via FLOW_CLS_STATS, no packet and byte counter synchronization
at this stage.

This patch also adds the action callback that specifies how to convert
the flow entry into the flow_rule object that is passed to the driver.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_tables: add flowtable offload control plane

This patch adds the NFTA_FLOWTABLE_FLAGS attribute that allows users to
specify the NF_FLOWTABLE_HW_OFFLOAD flag. This patch also adds a new
setup interface for the flowtable type to perform the flowtable offload
block callback configuration.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Add SPDX license identifier for more missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netfilter: nf_flow_table: move init code to nf_flow_table_core.c

Reduces duplication of .gc and .params in flowtable type definitions and
makes the API clearer

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_tables: fix flowtable free

Every flow_offload entry is added into the table twice. Because of this,
rhashtable_free_and_destroy can't be used, since it would call kfree for
each flow_offload object twice.

This patch cleans up the flowtable via nf_flow_table_iterate() to
schedule removal of entries by setting on the dying bit, then there is
an explicitly invocation of the garbage collector to release resources.

Based on patch from Felix Fietkau.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: flow table support for the mixed IPv4/IPv6 family

This patch adds the IPv6 flow table type, that implements the datapath
flow table to forward IPv6 traffic.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>