netfilter: xtables: allow xtables-nft only builds

Add hidden IP(6)_NF_IPTABLES_LEGACY symbol.

When any of the "old" builtin tables are enabled the "old" iptables
interface will be supported.

To disable the old set/getsockopt interface the existing options
for the builtin tables need to be turned off:

CONFIG_IP_NF_IPTABLES=m
CONFIG_IP_NF_FILTER is not set
CONFIG_IP_NF_NAT is not set
CONFIG_IP_NF_MANGLE is not set
CONFIG_IP_NF_RAW is not set
CONFIG_IP_NF_SECURITY is not set

Same for CONFIG_IP6_NF_ variants.

This allows to build a kernel that only supports ip(6)tables-nft
(iptables-over-nftables api).

In the future the _LEGACY symbol will become visible and the select
statements will be turned into 'depends on', but for now be on safe side
so "make oldconfig" won't break things.

Signed-off-by: Florian Westphal <fw@strlen.de>
This commit is contained in:
Florian Westphal 2024-01-24 10:21:11 +01:00
parent 4654467dc7
commit a9525c7f62
5 changed files with 34 additions and 17 deletions

View File

@ -10,6 +10,10 @@ config NF_DEFRAG_IPV4
tristate
default n
# old sockopt interface and eval loop
config IP_NF_IPTABLES_LEGACY
tristate
config NF_SOCKET_IPV4
tristate "IPv4 socket lookup support"
help
@ -152,7 +156,7 @@ config IP_NF_MATCH_ECN
config IP_NF_MATCH_RPFILTER
tristate '"rpfilter" reverse path filter match support'
depends on NETFILTER_ADVANCED
depends on IP_NF_MANGLE || IP_NF_RAW
depends on IP_NF_MANGLE || IP_NF_RAW || NFT_COMPAT
help
This option allows you to match packets whose replies would
go out via the interface the packet came in.
@ -173,6 +177,7 @@ config IP_NF_MATCH_TTL
config IP_NF_FILTER
tristate "Packet filtering"
default m if NETFILTER_ADVANCED=n
select IP_NF_IPTABLES_LEGACY
help
Packet filtering defines a table `filter', which has a series of
rules for simple packet filtering at local input, forwarding and
@ -182,7 +187,7 @@ config IP_NF_FILTER
config IP_NF_TARGET_REJECT
tristate "REJECT target support"
depends on IP_NF_FILTER
depends on IP_NF_FILTER || NFT_COMPAT
select NF_REJECT_IPV4
default m if NETFILTER_ADVANCED=n
help
@ -212,6 +217,7 @@ config IP_NF_NAT
default m if NETFILTER_ADVANCED=n
select NF_NAT
select NETFILTER_XT_NAT
select IP6_NF_IPTABLES_LEGACY
help
This enables the `nat' table in iptables. This allows masquerading,
port forwarding and other forms of full Network Address Port
@ -252,6 +258,7 @@ endif # IP_NF_NAT
config IP_NF_MANGLE
tristate "Packet mangling"
default m if NETFILTER_ADVANCED=n
select IP_NF_IPTABLES_LEGACY
help
This option adds a `mangle' table to iptables: see the man page for
iptables(8). This table is used for various packet alterations
@ -261,7 +268,7 @@ config IP_NF_MANGLE
config IP_NF_TARGET_ECN
tristate "ECN target support"
depends on IP_NF_MANGLE
depends on IP_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
help
This option adds a `ECN' target, which can be used in the iptables mangle
@ -286,6 +293,7 @@ config IP_NF_TARGET_TTL
# raw + specific targets
config IP_NF_RAW
tristate 'raw table support (required for NOTRACK/TRACE)'
select IP_NF_IPTABLES_LEGACY
help
This option adds a `raw' table to iptables. This table is the very
first in the netfilter framework and hooks in at the PREROUTING
@ -299,6 +307,7 @@ config IP_NF_SECURITY
tristate "Security table"
depends on SECURITY
depends on NETFILTER_ADVANCED
select IP_NF_IPTABLES_LEGACY
help
This option adds a `security' table to iptables, for use
with Mandatory Access Control (MAC) policy.

View File

@ -25,7 +25,7 @@ obj-$(CONFIG_NFT_FIB_IPV4) += nft_fib_ipv4.o
obj-$(CONFIG_NFT_DUP_IPV4) += nft_dup_ipv4.o
# generic IP tables
obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o
obj-$(CONFIG_IP_NF_IPTABLES_LEGACY) += ip_tables.o
# the three instances of ip_tables
obj-$(CONFIG_IP_NF_FILTER) += iptable_filter.o

View File

@ -6,6 +6,10 @@
menu "IPv6: Netfilter Configuration"
depends on INET && IPV6 && NETFILTER
# old sockopt interface and eval loop
config IP6_NF_IPTABLES_LEGACY
tristate
config NF_SOCKET_IPV6
tristate "IPv6 socket lookup support"
help
@ -147,7 +151,7 @@ config IP6_NF_MATCH_MH
config IP6_NF_MATCH_RPFILTER
tristate '"rpfilter" reverse path filter match support'
depends on NETFILTER_ADVANCED
depends on IP6_NF_MANGLE || IP6_NF_RAW
depends on IP6_NF_MANGLE || IP6_NF_RAW || NFT_COMPAT
help
This option allows you to match packets whose replies would
go out via the interface the packet came in.
@ -186,6 +190,8 @@ config IP6_NF_TARGET_HL
config IP6_NF_FILTER
tristate "Packet filtering"
default m if NETFILTER_ADVANCED=n
select IP6_NF_IPTABLES_LEGACY
tristate
help
Packet filtering defines a table `filter', which has a series of
rules for simple packet filtering at local input, forwarding and
@ -195,7 +201,7 @@ config IP6_NF_FILTER
config IP6_NF_TARGET_REJECT
tristate "REJECT target support"
depends on IP6_NF_FILTER
depends on IP6_NF_FILTER || NFT_COMPAT
select NF_REJECT_IPV6
default m if NETFILTER_ADVANCED=n
help
@ -221,6 +227,7 @@ config IP6_NF_TARGET_SYNPROXY
config IP6_NF_MANGLE
tristate "Packet mangling"
default m if NETFILTER_ADVANCED=n
select IP6_NF_IPTABLES_LEGACY
help
This option adds a `mangle' table to iptables: see the man page for
iptables(8). This table is used for various packet alterations
@ -230,6 +237,7 @@ config IP6_NF_MANGLE
config IP6_NF_RAW
tristate 'raw table support (required for TRACE)'
select IP6_NF_IPTABLES_LEGACY
help
This option adds a `raw' table to ip6tables. This table is the very
first in the netfilter framework and hooks in at the PREROUTING
@ -243,6 +251,7 @@ config IP6_NF_SECURITY
tristate "Security table"
depends on SECURITY
depends on NETFILTER_ADVANCED
select IP6_NF_IPTABLES_LEGACY
help
This option adds a `security' table to iptables, for use
with Mandatory Access Control (MAC) policy.
@ -254,6 +263,7 @@ config IP6_NF_NAT
depends on NF_CONNTRACK
depends on NETFILTER_ADVANCED
select NF_NAT
select IP6_NF_IPTABLES_LEGACY
select NETFILTER_XT_NAT
help
This enables the `nat' table in ip6tables. This allows masquerading,
@ -262,25 +272,23 @@ config IP6_NF_NAT
To compile it as a module, choose M here. If unsure, say N.
if IP6_NF_NAT
config IP6_NF_TARGET_MASQUERADE
tristate "MASQUERADE target support"
select NETFILTER_XT_TARGET_MASQUERADE
depends on IP6_NF_NAT
help
This is a backwards-compat option for the user's convenience
(e.g. when running oldconfig). It selects NETFILTER_XT_TARGET_MASQUERADE.
config IP6_NF_TARGET_NPT
tristate "NPT (Network Prefix translation) target support"
depends on IP6_NF_NAT || NFT_COMPAT
help
This option adds the `SNPT' and `DNPT' target, which perform
stateless IPv6-to-IPv6 Network Prefix Translation per RFC 6296.
To compile it as a module, choose M here. If unsure, say N.
endif # IP6_NF_NAT
endif # IP6_NF_IPTABLES
endmenu

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@ -4,7 +4,7 @@
#
# Link order matters here.
obj-$(CONFIG_IP6_NF_IPTABLES) += ip6_tables.o
obj-$(CONFIG_IP6_NF_IPTABLES_LEGACY) += ip6_tables.o
obj-$(CONFIG_IP6_NF_FILTER) += ip6table_filter.o
obj-$(CONFIG_IP6_NF_MANGLE) += ip6table_mangle.o
obj-$(CONFIG_IP6_NF_RAW) += ip6table_raw.o

View File

@ -818,7 +818,7 @@ config NETFILTER_XT_TARGET_AUDIT
config NETFILTER_XT_TARGET_CHECKSUM
tristate "CHECKSUM target support"
depends on IP_NF_MANGLE || IP6_NF_MANGLE
depends on IP_NF_MANGLE || IP6_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
help
This option adds a `CHECKSUM' target, which can be used in the iptables mangle
@ -869,7 +869,7 @@ config NETFILTER_XT_TARGET_CONNSECMARK
config NETFILTER_XT_TARGET_CT
tristate '"CT" target support'
depends on NF_CONNTRACK
depends on IP_NF_RAW || IP6_NF_RAW
depends on IP_NF_RAW || IP6_NF_RAW || NFT_COMPAT
depends on NETFILTER_ADVANCED
help
This options adds a `CT' target, which allows to specify initial
@ -880,7 +880,7 @@ config NETFILTER_XT_TARGET_CT
config NETFILTER_XT_TARGET_DSCP
tristate '"DSCP" and "TOS" target support'
depends on IP_NF_MANGLE || IP6_NF_MANGLE
depends on IP_NF_MANGLE || IP6_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
help
This option adds a `DSCP' target, which allows you to manipulate
@ -896,7 +896,7 @@ config NETFILTER_XT_TARGET_DSCP
config NETFILTER_XT_TARGET_HL
tristate '"HL" hoplimit target support'
depends on IP_NF_MANGLE || IP6_NF_MANGLE
depends on IP_NF_MANGLE || IP6_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
help
This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
@ -1080,7 +1080,7 @@ config NETFILTER_XT_TARGET_TPROXY
depends on NETFILTER_ADVANCED
depends on IPV6 || IPV6=n
depends on IP6_NF_IPTABLES || IP6_NF_IPTABLES=n
depends on IP_NF_MANGLE
depends on IP_NF_MANGLE || NFT_COMPAT
select NF_DEFRAG_IPV4
select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES != n
select NF_TPROXY_IPV4
@ -1147,7 +1147,7 @@ config NETFILTER_XT_TARGET_TCPMSS
config NETFILTER_XT_TARGET_TCPOPTSTRIP
tristate '"TCPOPTSTRIP" target support'
depends on IP_NF_MANGLE || IP6_NF_MANGLE
depends on IP_NF_MANGLE || IP6_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
help
This option adds a "TCPOPTSTRIP" target, which allows you to strip