This patch adds support for overloading stateful objects operations
through the select_ops() callback, just as it is implemented for
expressions.
This change is needed for upcoming additions to the stateful objects
infrastructure.
Signed-off-by: Pablo M. Bermudo Garay <pablombg@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
this is needed by the upcoming ct helper object type --
we'd like to be able use the table family (ip, ip6, inet) to figure
out which helper has to be requested.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Dump and reset doesn't work unless cmpxchg64() is used both from packet
and control plane paths. This approach is going to be slow though.
Instead, use a percpu seqcount to fetch counters consistently, then
subtract bytes and packets in case a reset was requested.
The cpu that running over the reset code is guaranteed to own this stats
exclusively, we have to turn counters into signed 64bit though so stats
update on reset don't get wrong on underflow.
This patch is based on original sketch from Eric Dumazet.
Fixes: 43da04a593 ("netfilter: nf_tables: atomic dump and reset for stateful objects")
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new NFT_MSG_GETOBJ_RESET command perform an atomic
dump-and-reset of the stateful object. This also comes with add support
for atomic dump and reset for counter and quota objects.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
The nft_counter_init() and nft_counter_clone() functions should return
negative error value -ENOMEM instead of positive ENOMEM.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With the conversion of the counter expressions to make it percpu, we
need to clone the percpu memory area, otherwise we crash when using
counters from flow tables.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch converts the existing seqlock to per-cpu counters.
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Suggested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a flag to mark stateful expressions.
This is used for dynamic expression instanstiation to limit the usable
expressions. Strictly speaking only the dynset expression can not be
used in order to avoid recursion, but since dynamically instantiating
non-stateful expressions will simply create an identical copy, which
behaves no differently than the original, this limits to expressions
where it actually makes sense to dynamically instantiate them.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Replace the array of registers passed to expressions by a struct nft_regs,
containing the verdict as a seperate member, which aliases to the
NFT_REG_VERDICT register.
This is needed to seperate the verdict from the data registers completely,
so their size can be changed.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Split the expression ops into two parts and support overloading of
the runtime expression ops based on the requested function through
a ->select_ops() callback.
This can be used to provide optimized implementations, for instance
for loading small aligned amounts of data from the packet or inlining
frequently used operations into the main evaluation loop.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds nftables which is the intended successor of iptables.
This packet filtering framework reuses the existing netfilter hooks,
the connection tracking system, the NAT subsystem, the transparent
proxying engine, the logging infrastructure and the userspace packet
queueing facilities.
In a nutshell, nftables provides a pseudo-state machine with 4 general
purpose registers of 128 bits and 1 specific purpose register to store
verdicts. This pseudo-machine comes with an extensible instruction set,
a.k.a. "expressions" in the nftables jargon. The expressions included
in this patch provide the basic functionality, they are:
* bitwise: to perform bitwise operations.
* byteorder: to change from host/network endianess.
* cmp: to compare data with the content of the registers.
* counter: to enable counters on rules.
* ct: to store conntrack keys into register.
* exthdr: to match IPv6 extension headers.
* immediate: to load data into registers.
* limit: to limit matching based on packet rate.
* log: to log packets.
* meta: to match metainformation that usually comes with the skbuff.
* nat: to perform Network Address Translation.
* payload: to fetch data from the packet payload and store it into
registers.
* reject (IPv4 only): to explicitly close connection, eg. TCP RST.
Using this instruction-set, the userspace utility 'nft' can transform
the rules expressed in human-readable text representation (using a
new syntax, inspired by tcpdump) to nftables bytecode.
nftables also inherits the table, chain and rule objects from
iptables, but in a more configurable way, and it also includes the
original datatype-agnostic set infrastructure with mapping support.
This set infrastructure is enhanced in the follow up patch (netfilter:
nf_tables: add netlink set API).
This patch includes the following components:
* the netlink API: net/netfilter/nf_tables_api.c and
include/uapi/netfilter/nf_tables.h
* the packet filter core: net/netfilter/nf_tables_core.c
* the expressions (described above): net/netfilter/nft_*.c
* the filter tables: arp, IPv4, IPv6 and bridge:
net/ipv4/netfilter/nf_tables_ipv4.c
net/ipv6/netfilter/nf_tables_ipv6.c
net/ipv4/netfilter/nf_tables_arp.c
net/bridge/netfilter/nf_tables_bridge.c
* the NAT table (IPv4 only):
net/ipv4/netfilter/nf_table_nat_ipv4.c
* the route table (similar to mangle):
net/ipv4/netfilter/nf_table_route_ipv4.c
net/ipv6/netfilter/nf_table_route_ipv6.c
* internal definitions under:
include/net/netfilter/nf_tables.h
include/net/netfilter/nf_tables_core.h
* It also includes an skeleton expression:
net/netfilter/nft_expr_template.c
and the preliminary implementation of the meta target
net/netfilter/nft_meta_target.c
It also includes a change in struct nf_hook_ops to add a new
pointer to store private data to the hook, that is used to store
the rule list per chain.
This patch is based on the patch from Patrick McHardy, plus merged
accumulated cleanups, fixes and small enhancements to the nftables
code that has been done since 2009, which are:
From Patrick McHardy:
* nf_tables: adjust netlink handler function signatures
* nf_tables: only retry table lookup after successful table module load
* nf_tables: fix event notification echo and avoid unnecessary messages
* nft_ct: add l3proto support
* nf_tables: pass expression context to nft_validate_data_load()
* nf_tables: remove redundant definition
* nft_ct: fix maxattr initialization
* nf_tables: fix invalid event type in nf_tables_getrule()
* nf_tables: simplify nft_data_init() usage
* nf_tables: build in more core modules
* nf_tables: fix double lookup expression unregistation
* nf_tables: move expression initialization to nf_tables_core.c
* nf_tables: build in payload module
* nf_tables: use NFPROTO constants
* nf_tables: rename pid variables to portid
* nf_tables: save 48 bits per rule
* nf_tables: introduce chain rename
* nf_tables: check for duplicate names on chain rename
* nf_tables: remove ability to specify handles for new rules
* nf_tables: return error for rule change request
* nf_tables: return error for NLM_F_REPLACE without rule handle
* nf_tables: include NLM_F_APPEND/NLM_F_REPLACE flags in rule notification
* nf_tables: fix NLM_F_MULTI usage in netlink notifications
* nf_tables: include NLM_F_APPEND in rule dumps
From Pablo Neira Ayuso:
* nf_tables: fix stack overflow in nf_tables_newrule
* nf_tables: nft_ct: fix compilation warning
* nf_tables: nft_ct: fix crash with invalid packets
* nft_log: group and qthreshold are 2^16
* nf_tables: nft_meta: fix socket uid,gid handling
* nft_counter: allow to restore counters
* nf_tables: fix module autoload
* nf_tables: allow to remove all rules placed in one chain
* nf_tables: use 64-bits rule handle instead of 16-bits
* nf_tables: fix chain after rule deletion
* nf_tables: improve deletion performance
* nf_tables: add missing code in route chain type
* nf_tables: rise maximum number of expressions from 12 to 128
* nf_tables: don't delete table if in use
* nf_tables: fix basechain release
From Tomasz Bursztyka:
* nf_tables: Add support for changing users chain's name
* nf_tables: Change chain's name to be fixed sized
* nf_tables: Add support for replacing a rule by another one
* nf_tables: Update uapi nftables netlink header documentation
From Florian Westphal:
* nft_log: group is u16, snaplen u32
From Phil Oester:
* nf_tables: operational limit match
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo M. Bermudo Garay