linux/net/netfilter
Florian Westphal f92b40a8b2 netfilter: core: only allow one nat hook per hook point
The netfilter NAT core cannot deal with more than one NAT hook per hook
location (prerouting, input ...), because the NAT hooks install a NAT null
binding in case the iptables nat table (iptable_nat hooks) or the
corresponding nftables chain (nft nat hooks) doesn't specify a nat
transformation.

Null bindings are needed to detect port collsisions between NAT-ed and
non-NAT-ed connections.

This causes nftables NAT rules to not work when iptable_nat module is
loaded, and vice versa because nat binding has already been attached
when the second nat hook is consulted.

The netfilter core is not really the correct location to handle this
(hooks are just hooks, the core has no notion of what kinds of side
 effects a hook implements), but its the only place where we can check
for conflicts between both iptables hooks and nftables hooks without
adding dependencies.

So add nat annotation to hook_ops to describe those hooks that will
add NAT bindings and then make core reject if such a hook already exists.
The annotation fills a padding hole, in case further restrictions appar
we might change this to a 'u8 type' instead of bool.

iptables error if nft nat hook active:
iptables -t nat -A POSTROUTING -j MASQUERADE
iptables v1.4.21: can't initialize iptables table `nat': File exists
Perhaps iptables or your kernel needs to be upgraded.

nftables error if iptables nat table present:
nft -f /etc/nftables/ipv4-nat
/usr/etc/nftables/ipv4-nat:3:1-2: Error: Could not process rule: File exists
table nat {
^^

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:13 +01:00
..
ipset netfilter: ipset: add resched points during set listing 2018-01-08 18:01:04 +01:00
ipvs netfilter: ipvs: Remove useless ipvsh param of frag_safe_skb_hp 2018-01-08 18:01:02 +01:00
core.c netfilter: core: only allow one nat hook per hook point 2018-01-08 18:01:13 +01:00
Kconfig netfilter: don't allocate space for arp/bridge hooks unless needed 2018-01-08 18:01:11 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nf_conntrack_acct.c netfilter: conntrack: mark extension structs as const 2017-04-26 09:30:22 +02:00
nf_conntrack_amanda.c netfilter: use nf_conntrack_helpers_register when possible 2017-06-19 19:13:21 +02:00
nf_conntrack_broadcast.c netfilter: Remove duplicated rcu_read_lock. 2017-07-24 13:24:46 +02:00
nf_conntrack_core.c Modules updates for v4.15 2017-11-15 13:46:33 -08:00
nf_conntrack_ecache.c netfilter: conntrack: mark extension structs as const 2017-04-26 09:30:22 +02:00
nf_conntrack_expect.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
nf_conntrack_extend.c net: Replace NF_CT_ASSERT() with WARN_ON(). 2017-09-04 13:25:19 +02:00
nf_conntrack_ftp.c netfilter: helpers: remove data_len usage for inkernel helpers 2017-04-19 17:55:17 +02:00
nf_conntrack_h323_asn1.c netfilter: nf_conntrack_h323: Remove unwanted comments. 2018-01-08 18:01:05 +01:00
nf_conntrack_h323_main.c netfilter: nf_conntrack_h323: Remove unwanted comments. 2018-01-08 18:01:05 +01:00
nf_conntrack_h323_types.c
nf_conntrack_helper.c netfilter: expect: add and use nf_ct_expect_iterate helpers 2017-07-31 19:09:38 +02:00
nf_conntrack_irc.c netfilter: helpers: remove data_len usage for inkernel helpers 2017-04-19 17:55:17 +02:00
nf_conntrack_l3proto_generic.c netfilter: conntrack: place print_tuple in procfs part 2017-08-24 18:52:32 +02:00
nf_conntrack_labels.c netfilter: conntrack: mark extension structs as const 2017-04-26 09:30:22 +02:00
nf_conntrack_netbios_ns.c netfilter: helper: add build-time asserts for helper data size 2017-04-19 17:55:16 +02:00
nf_conntrack_netlink.c netfilter: conntrack: remove nlattr_size pointer from l4proto trackers 2018-01-08 16:47:14 +01:00
nf_conntrack_pptp.c netfilter: Remove duplicated rcu_read_lock. 2017-07-24 13:24:46 +02:00
nf_conntrack_proto_dccp.c netfilter: conntrack: l4 protocol trackers can be const 2018-01-08 18:00:54 +01:00
nf_conntrack_proto_generic.c netfilter: conntrack: timeouts can be const 2018-01-08 18:01:02 +01:00
nf_conntrack_proto_gre.c netfilter: conntrack: timeouts can be const 2018-01-08 18:01:02 +01:00
nf_conntrack_proto_sctp.c netfilter: conntrack: timeouts can be const 2018-01-08 18:01:02 +01:00
nf_conntrack_proto_tcp.c netfilter: conntrack: timeouts can be const 2018-01-08 18:01:02 +01:00
nf_conntrack_proto_udp.c netfilter: conntrack: timeouts can be const 2018-01-08 18:01:02 +01:00
nf_conntrack_proto.c netfilter: conntrack: constify list of builtin trackers 2018-01-08 16:47:14 +01:00
nf_conntrack_sane.c netfilter: helpers: remove data_len usage for inkernel helpers 2017-04-19 17:55:17 +02:00
nf_conntrack_seqadj.c netfilter: conntrack: mark extension structs as const 2017-04-26 09:30:22 +02:00
nf_conntrack_sip.c netfilter: Remove duplicated rcu_read_lock. 2017-07-24 13:24:46 +02:00
nf_conntrack_snmp.c
nf_conntrack_standalone.c net: Replace NF_CT_ASSERT() with WARN_ON(). 2017-09-04 13:25:19 +02:00
nf_conntrack_tftp.c netfilter: helpers: remove data_len usage for inkernel helpers 2017-04-19 17:55:17 +02:00
nf_conntrack_timeout.c netfilter: conntrack: mark extension structs as const 2017-04-26 09:30:22 +02:00
nf_conntrack_timestamp.c netfilter: conntrack: mark extension structs as const 2017-04-26 09:30:22 +02:00
nf_dup_netdev.c netfilter: dup: resolve warnings about missing prototypes 2017-05-29 11:32:36 +02:00
nf_internals.h netfilter: core: remove synchronize_net call if nfqueue is used 2018-01-08 18:01:06 +01:00
nf_log_common.c netfilter: nf_log: do not assume ethernet header in netdev family 2016-12-04 20:45:33 +01:00
nf_log_netdev.c netfilter: nf_log: do not assume ethernet header in netdev family 2016-12-04 20:45:33 +01:00
nf_log.c netfilter: nf_log: don't call synchronize_rcu in nf_log_unset 2017-05-01 11:19:07 +02:00
nf_nat_amanda.c netfilter: nat: nf_nat_mangle_{udp,tcp}_packet returns boolean 2017-04-06 22:01:38 +02:00
nf_nat_core.c netfilter: nat: use test_and_clear_bit when deleting ct from bysource list 2017-10-24 17:54:47 +02:00
nf_nat_ftp.c treewide: Fix function prototypes for module_param_call() 2017-10-31 15:30:37 +01:00
nf_nat_helper.c netfilter: nat: nf_nat_mangle_{udp,tcp}_packet returns boolean 2017-04-06 22:01:38 +02:00
nf_nat_irc.c treewide: Fix function prototypes for module_param_call() 2017-10-31 15:30:37 +01:00
nf_nat_proto_common.c
nf_nat_proto_dccp.c netfilter: built-in NAT support for DCCP 2016-12-04 20:45:30 +01:00
nf_nat_proto_sctp.c sctp: remove the typedef sctp_sctphdr_t 2017-07-01 09:08:41 -07:00
nf_nat_proto_tcp.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
nf_nat_proto_udp.c netfilter: nat: merge udp and udplite helpers 2017-01-03 14:33:25 +01:00
nf_nat_proto_unknown.c
nf_nat_redirect.c net: Replace NF_CT_ASSERT() with WARN_ON(). 2017-09-04 13:25:19 +02:00
nf_nat_sip.c
nf_nat_tftp.c
nf_queue.c netfilter: don't allocate space for arp/bridge hooks unless needed 2018-01-08 18:01:11 +01:00
nf_sockopt.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nf_synproxy_core.c tcp: switch TCP TS option (RFC 7323) to 1ms clock 2017-05-17 16:06:01 -04:00
nf_tables_api.c netfilter: core: only allow one nat hook per hook point 2018-01-08 18:01:13 +01:00
nf_tables_core.c netfilter: constify nf_loginfo structures 2017-08-02 14:25:59 +02:00
nf_tables_inet.c netfilter: Add the missed return value check of nft_register_chain_type 2016-09-12 19:54:45 +02:00
nf_tables_netdev.c netfilter: nf_tables: add nft_is_base_chain() helper 2017-04-06 18:32:04 +02:00
nf_tables_trace.c netfilter: nf_tables: Allow chain name of up to 255 chars 2017-07-31 20:41:57 +02:00
nfnetlink_acct.c netfilter: nfnetlink: extended ACK reporting 2017-06-19 19:38:24 +02:00
nfnetlink_cthelper.c netfilter: nfnetlink_cthelper: Add missing permission checks 2017-12-04 11:30:09 +01:00
nfnetlink_cttimeout.c netfilter: conntrack: make protocol tracker pointers const 2017-08-24 18:52:33 +02:00
nfnetlink_log.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-12-13 14:12:20 -05:00
nfnetlink_queue.c netfilter: core: remove synchronize_net call if nfqueue is used 2018-01-08 18:01:06 +01:00
nfnetlink.c netfilter: nfnetlink: Improve input length sanitization in nfnetlink_rcv 2017-07-17 13:27:46 +02:00
nft_bitwise.c netfilter: nf_tables: revisit chain/object refcounting from elements 2017-05-15 12:51:41 +02:00
nft_byteorder.c netfilter: nf_tables: simplify the basic expressions' init routine 2016-11-09 23:42:23 +01:00
nft_cmp.c netfilter: mark expected switch fall-throughs 2018-01-08 18:01:01 +01:00
nft_compat.c netfilter: nft_compat: check extension hook mask only if set 2017-07-19 11:53:30 +02:00
nft_counter.c netfilter: nf_tables: add select_ops for stateful objects 2017-09-04 13:25:09 +02:00
nft_ct.c netfilter: conntrack: move nf_ct_netns_{get,put}() to core 2017-11-06 16:48:39 +01:00
nft_dup_netdev.c netfilter: nf_tables: add packet duplication to the netdev family 2016-01-03 21:04:23 +01:00
nft_dynset.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-05-03 10:11:26 -04:00
nft_exthdr.c netfilter: exthdr: add missign attributes to policy 2017-12-11 13:46:04 +01:00
nft_fib_inet.c netfilter: nf_tables: use hook state from xt_action_param structure 2016-11-03 11:52:34 +01:00
nft_fib_netdev.c netfilter: nf_tables: add fib expression to the netdev family 2017-07-31 19:01:40 +02:00
nft_fib.c netfilter: nft_fib: Support existence check 2017-03-13 13:45:36 +01:00
nft_fwd_netdev.c netfilter: add and use nf_fwd_netdev_egress 2016-12-06 21:48:22 +01:00
nft_hash.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-05-01 10:47:53 -04:00
nft_immediate.c netfilter: nf_tables: revisit chain/object refcounting from elements 2017-05-15 12:51:41 +02:00
nft_limit.c netfilter: nft_limit: add stateful object type 2017-09-04 13:25:16 +02:00
nft_log.c netfilter: nft_log: restrict the log prefix length to 127 2017-01-24 21:46:29 +01:00
nft_lookup.c netfilter: nf_tables: add nft_set_lookup() 2017-03-06 18:23:23 +01:00
nft_masq.c netfilter: nf_tables: validate the expr explicitly after init successfully 2017-03-06 18:22:12 +01:00
nft_meta.c netfilter: Remove exceptional & on function name 2017-04-07 18:24:47 +02:00
nft_nat.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-03-23 16:41:27 -07:00
nft_numgen.c netfilter: Remove exceptional & on function name 2017-04-07 18:24:47 +02:00
nft_objref.c netfilter: nf_tables: add select_ops for stateful objects 2017-09-04 13:25:09 +02:00
nft_payload.c netfilter: fix a few (harmless) sparse warnings 2017-08-28 17:42:56 +02:00
nft_queue.c netfilter: Remove exceptional & on function name 2017-04-07 18:24:47 +02:00
nft_quota.c netfilter: nf_tables: add select_ops for stateful objects 2017-09-04 13:25:09 +02:00
nft_range.c netfilter: nf_tables: revisit chain/object refcounting from elements 2017-05-15 12:51:41 +02:00
nft_redir.c netfilter: nf_tables: validate the expr explicitly after init successfully 2017-03-06 18:22:12 +01:00
nft_reject_inet.c netfilter: nf_tables: validate the expr explicitly after init successfully 2017-03-06 18:22:12 +01:00
nft_reject.c netfilter: nf_tables: validate the expr explicitly after init successfully 2017-03-06 18:22:12 +01:00
nft_rt.c netfilter: rt: account for tcp header size too 2017-08-28 18:14:30 +02:00
nft_set_bitmap.c netfilter: nf_tables: get set elements via netlink 2017-11-07 01:00:31 +01:00
nft_set_hash.c rhashtable: Change rhashtable_walk_start to return void 2017-12-11 09:58:38 -05:00
nft_set_rbtree.c netfilter: nf_tables: get set elements via netlink 2017-11-07 01:00:31 +01:00
x_tables.c netfilter: xtables: add and use xt_request_find_table_lock 2018-01-08 18:01:12 +01:00
xt_addrtype.c netfilter: Remove duplicated rcu_read_lock. 2017-07-24 13:24:46 +02:00
xt_AUDIT.c audit: normalize NETFILTER_PKT 2017-05-02 10:16:04 -04:00
xt_bpf.c netfilter: xt_bpf: add overflow checks 2017-12-04 11:41:20 +01:00
xt_cgroup.c xtables: extend matches and targets with .usersize 2017-01-09 17:24:55 +01:00
xt_CHECKSUM.c
xt_CLASSIFY.c
xt_cluster.c netfilter: remove nf_ct_is_untracked 2017-04-15 11:51:33 +02:00
xt_comment.c
xt_connbytes.c netfilter: add and use nf_ct_netns_get/put 2016-12-04 21:16:50 +01:00
xt_connlabel.c netfilter: remove nf_ct_is_untracked 2017-04-15 11:51:33 +02:00
xt_connlimit.c netfilter: xt_connlimit: remove mask argument 2017-11-06 14:47:30 +01:00
xt_connmark.c netfilter: remove nf_ct_is_untracked 2017-04-15 11:51:33 +02:00
xt_CONNSECMARK.c netfilter: add and use nf_ct_netns_get/put 2016-12-04 21:16:50 +01:00
xt_conntrack.c netfilter: kill the fake untracked conntrack objects 2017-04-15 11:47:57 +02:00
xt_cpu.c
xt_CT.c netfilter: conntrack: make protocol tracker pointers const 2017-08-24 18:52:33 +02:00
xt_dccp.c
xt_devgroup.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
xt_dscp.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
xt_DSCP.c
xt_ecn.c
xt_esp.c
xt_hashlimit.c netfilter: xt_hashlimit: fix build error caused by 64bit division 2017-09-08 18:55:53 +02:00
xt_helper.c netfilter: add and use nf_ct_netns_get/put 2016-12-04 21:16:50 +01:00
xt_hl.c
xt_HL.c
xt_HMARK.c netfilter: remove nf_ct_is_untracked 2017-04-15 11:51:33 +02:00
xt_IDLETIMER.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
xt_ipcomp.c netfilter: xt_ipcomp: add "ip[6]t_ipcomp" module alias name 2016-10-17 17:38:19 +02:00
xt_iprange.c
xt_ipvs.c netfilter: remove nf_ct_is_untracked 2017-04-15 11:51:33 +02:00
xt_l2tp.c
xt_LED.c treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
xt_length.c
xt_limit.c netfilter: limit: use per-rule spinlock to improve the scalability 2017-03-13 19:30:31 +01:00
xt_LOG.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
xt_mac.c
xt_mark.c netfilter: xt_MARK: Add ARP support 2015-05-14 13:00:27 +02:00
xt_multiport.c netfilter: xt_multiport: Fix wrong unmatch result with multiple ports 2016-12-06 21:48:20 +01:00
xt_nat.c net: Replace NF_CT_ASSERT() with WARN_ON(). 2017-09-04 13:25:19 +02:00
xt_NETMAP.c net: Replace NF_CT_ASSERT() with WARN_ON(). 2017-09-04 13:25:19 +02:00
xt_nfacct.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
xt_NFLOG.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
xt_NFQUEUE.c netfilter: x_tables: move hook state into xt_action_param structure 2016-11-03 10:56:21 +01:00
xt_osf.c netfilter: xt_osf: Add missing permission checks 2017-12-06 09:01:18 +01:00
xt_owner.c sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h> 2017-03-02 08:42:31 +01:00
xt_physdev.c netfilter: physdev: add missed blank 2016-08-12 00:42:14 +02:00
xt_pkttype.c netfilter: pkttype: unnecessary to check ipv6 multicast address 2017-01-18 20:32:43 +01:00
xt_policy.c xfrm: Move child route linkage into xfrm_dst. 2017-11-30 09:54:26 -05:00
xt_quota.c xtables: extend matches and targets with .usersize 2017-01-09 17:24:55 +01:00
xt_rateest.c xtables: extend matches and targets with .usersize 2017-01-09 17:24:55 +01:00
xt_RATEEST.c xtables: extend matches and targets with .usersize 2017-01-09 17:24:55 +01:00
xt_realm.c
xt_recent.c netfilter: remove unused variable 2017-07-25 12:31:37 -07:00
xt_REDIRECT.c netfilter: nat: add dependencies on conntrack module 2016-12-04 21:16:51 +01:00
xt_repldata.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xt_sctp.c sctp: remove the typedef sctp_chunkhdr_t 2017-07-01 09:08:41 -07:00
xt_SECMARK.c
xt_set.c netfilter: ipset: Improve skbinfo get/init helpers 2016-11-10 13:28:42 +01:00
xt_socket.c netfilter: xt_socket: Restore mark from full sockets only 2017-09-26 20:04:34 +02:00
xt_state.c netfilter: kill the fake untracked conntrack objects 2017-04-15 11:47:57 +02:00
xt_statistic.c
xt_string.c xtables: extend matches and targets with .usersize 2017-01-09 17:24:55 +01:00
xt_tcpmss.c
xt_TCPMSS.c netfilter: Remove duplicated rcu_read_lock. 2017-07-24 13:24:46 +02:00
xt_TCPOPTSTRIP.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
xt_tcpudp.c netfilter: Convert FWINV<[foo]> macros and uses to NF_INVF 2016-07-03 10:55:07 +02:00
xt_TEE.c xtables: extend matches and targets with .usersize 2017-01-09 17:24:55 +01:00
xt_time.c ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
xt_TPROXY.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2017-09-03 17:08:42 -07:00
xt_TRACE.c netfilter: xt_TRACE: add explicitly nf_logger_find_get call 2016-06-23 13:26:49 +02:00
xt_u32.c