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>
Same conversion as for table names, use NFT_NAME_MAXLEN as upper
boundary as well.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Same conversion as for table names, use NFT_NAME_MAXLEN as upper
boundary as well.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Same conversion as for table names, use NFT_NAME_MAXLEN as upper
boundary as well.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Allocate all table names dynamically to allow for arbitrary lengths but
introduce NFT_NAME_MAXLEN as an upper sanity boundary. It's value was
chosen to allow using a domain name as per RFC 1035.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the infrastructure to support several implementations of
the same set type. This selection will be based on the set description
and the features available for this set. This allow us to select set
backend implementation that will result in better performance numbers.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Andreas reports that the following incremental update using our commit
protocol doesn't work.
# nft -f incremental-update.nft
delete element ip filter client_to_any { 10.180.86.22 : goto CIn_1 }
delete chain ip filter CIn_1
... Error: Could not process rule: Device or resource busy
The existing code is not well-integrated into the commit phase protocol,
since element deletions do not result in refcount decrement from the
preparation phase. This results in bogus EBUSY errors like the one
above.
Two new functions come with this patch:
* nft_set_elem_activate() function is used from the abort path, to
restore the set element refcounting on objects that occurred from
the preparation phase.
* nft_set_elem_deactivate() that is called from nft_del_setelem() to
decrement set element refcounting on objects from the preparation
phase in the commit protocol.
The nft_data_uninit() has been renamed to nft_data_release() since this
function does not uninitialize any data store in the data register,
instead just releases the references to objects. Moreover, a new
function nft_data_hold() has been introduced to be used from
nft_set_elem_activate().
Reported-by: Andreas Schultz <aschultz@tpip.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/net/ethernet/broadcom/genet/bcmmii.c
drivers/net/hyperv/netvsc.c
kernel/bpf/hashtab.c
Almost entirely overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 1f48ff6c53.
This patch is not required anymore now that we keep a dummy list of
set elements in the bitmap set implementation, so revert this before
we forget this code has no clients.
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>
Currently, there are two different methods to store an u16 integer to
the u32 data register. For example:
u32 *dest = ®s->data[priv->dreg];
1. *dest = 0; *(u16 *) dest = val_u16;
2. *dest = val_u16;
For method 1, the u16 value will be stored like this, either in
big-endian or little-endian system:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| Value | 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+
For method 2, in little-endian system, the u16 value will be the same
as listed above. But in big-endian system, the u16 value will be stored
like this:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| 0 | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+
So later we use "memcmp(®s->data[priv->sreg], data, 2);" to do
compare in nft_cmp, nft_lookup expr ..., method 2 will get the wrong
result in big-endian system, as 0~15 bits will always be zero.
For the similar reason, when loading an u16 value from the u32 data
register, we should use "*(u16 *) sreg;" instead of "(u16)*sreg;",
the 2nd method will get the wrong value in the big-endian system.
So introduce some wrapper functions to store/load an u8 or u16
integer to/from the u32 data register, and use them in the right
place.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This new function consolidates set lookup via either name or ID by
introducing a new nft_set_lookup() function. Replace existing spots
where we can use this too.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The underlying nlmsg_multicast() already sets sk->sk_err for us to
notify socket overruns, so we should not do anything with this return
value. So we just call nfnetlink_set_err() if:
1) We fail to allocate the netlink message.
or
2) We don't have enough space in the netlink message to place attributes,
which means that we likely need to allocate a larger message.
Before this patch, the internal ESRCH netlink error code was propagated
to userspace, which is quite misleading. Netlink semantics mandate that
listeners just hit ENOBUFS if the socket buffer overruns.
Reported-by: Alexander Alemayhu <alexander@alemayhu.com>
Tested-by: Alexander Alemayhu <alexander@alemayhu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This new attribute allows us to uniquely identify a rule in transaction.
Robots may trigger an insertion followed by deletion in a batch, in that
scenario we still don't have a public rule handle that we can use to
delete the rule. This is similar to the NFTA_SET_ID attribute that
allows us to refer to an anonymous set from a batch.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The space notation allows us to classify the set backend implementation
based on the amount of required memory. This provides an order of the
set representation scalability in terms of memory. The size field is
still left in place so use this if the userspace provides no explicit
number of elements, so we cannot calculate the real memory that this set
needs. This also helps us break ties in the set backend selection
routine, eg. two backend implementations provide the same performance.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use lookup as field name instead, to prepare the introduction of the
memory class in a follow up patch.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This provides context to walk callback iterator, thus, we know if the
walk happens from the set flush path. This is required by the new bitmap
set type coming in a follow up patch which has no real struct
nft_set_ext, so it has to allocate it based on the two bit compact
element representation.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Although semantics are similar to deactivate() with no implicit element
lookup, this is only called from the set flush path, so better rename
this to flush().
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds support for set flushing, that consists of walking over
the set elements if the NFTA_SET_ELEM_LIST_ELEMENTS attribute is set.
This patch requires the following changes:
1) Add set->ops->deactivate_one() operation: This allows us to
deactivate an element from the set element walk path, given we can
skip the lookup that happens in ->deactivate().
2) Add a new nft_trans_alloc_gfp() function since we need to allocate
transactions using GFP_ATOMIC given the set walk path happens with
held rcu_read_lock.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch allows you to refer to stateful objects from set elements.
This provides the infrastructure to create maps where the right hand
side of the mapping is a stateful object.
This allows us to build dictionaries of stateful objects, that you can
use to perform fast lookups using any arbitrary key combination.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Notify on depleted quota objects. The NFT_QUOTA_F_DEPLETED flag
indicates we have reached overquota.
Add pointer to table from nft_object, so we can use it when sending the
depletion notification to userspace.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Introduce nf_tables_obj_notify() to notify internal state changes in
stateful objects. This is used by the quota object to report depletion
in a follow up patch.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
This patch augments nf_tables to support stateful objects. This new
infrastructure allows you to create, dump and delete stateful objects,
that are identified by a user-defined name.
This patch adds the generic infrastructure, follow up patches add
support for two stateful objects: counters and quotas.
This patch provides a native infrastructure for nf_tables to replace
nfacct, the extended accounting infrastructure for iptables.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Couple conflicts resolved here:
1) In the MACB driver, a bug fix to properly initialize the
RX tail pointer properly overlapped with some changes
to support variable sized rings.
2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix
overlapping with a reorganization of the driver to support
ACPI, OF, as well as PCI variants of the chip.
3) In 'net' we had several probe error path bug fixes to the
stmmac driver, meanwhile a lot of this code was cleaned up
and reorganized in 'net-next'.
4) The cls_flower classifier obtained a helper function in
'net-next' called __fl_delete() and this overlapped with
Daniel Borkamann's bug fix to use RCU for object destruction
in 'net'. It also overlapped with Jiri's change to guard
the rhashtable_remove_fast() call with a check against
tc_skip_sw().
5) In mlx4, a revert bug fix in 'net' overlapped with some
unrelated changes in 'net-next'.
6) In geneve, a stale header pointer after pskb_expand_head()
bug fix in 'net' overlapped with a large reorganization of
the same code in 'net-next'. Since the 'net-next' code no
longer had the bug in question, there was nothing to do
other than to simply take the 'net-next' hunks.
Signed-off-by: David S. Miller <davem@davemloft.net>
As Liping Zhang reports, after commit a8b1e36d0d ("netfilter: nft_dynset:
fix element timeout for HZ != 1000"), priv->timeout was stored in jiffies,
while set->timeout was stored in milliseconds. This is inconsistent and
incorrect.
Firstly, we already call msecs_to_jiffies in nft_set_elem_init, so
priv->timeout will be converted to jiffies twice.
Secondly, if the user did not specify the NFTA_DYNSET_TIMEOUT attr,
set->timeout will be used, but we forget to call msecs_to_jiffies
when do update elements.
Fix this by using jiffies internally for traditional sets and doing the
conversions to/from msec when interacting with userspace - as dynset
already does.
This is preferable to doing the conversions, when elements are inserted or
updated, because this can happen very frequently on busy dynsets.
Fixes: a8b1e36d0d ("netfilter: nft_dynset: fix element timeout for HZ != 1000")
Reported-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Anders K. Pedersen <akp@cohaesio.com>
Acked-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Don't copy relevant fields from hook state structure, instead use the
one that is already available in struct xt_action_param.
This patch also adds a set of new wrapper functions to fetch relevant
hook state structure fields.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Place pointer to hook state in xt_action_param structure instead of
copying the fields that we need. After this change xt_action_param fits
into one cacheline.
This patch also adds a set of new wrapper functions to fetch relevant
hook state structure fields.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Commit 36b701fae1 ("netfilter: nf_tables: validate maximum value of
u32 netlink attributes") introduced nft_parse_u32_check with a return
value of "unsigned int", yet on error it returns "-ERANGE".
This patch corrects the mismatch by changing the return value to "int",
which happens to match the actual users of nft_parse_u32_check already.
Found by Coverity, CID 1373930.
Note that commit 21a9e0f156 ("netfilter: nft_exthdr: fix error
handling in nft_exthdr_init()) attempted to address the issue, but
did not address the return type of nft_parse_u32_check.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Cc: Laura Garcia Liebana <nevola@gmail.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 36b701fae1 ("netfilter: nf_tables: validate maximum value...")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When nft_expr_clone failed, a series of problems will happen:
1. module refcnt will leak, we call __module_get at the beginning but
we forget to put it back if ops->clone returns fail
2. memory will be leaked, if clone fail, we just return NULL and forget
to free the alloced element
3. set->nelems will become incorrect when set->size is specified. If
clone fail, we should decrease the set->nelems
Now this patch fixes these problems. And fortunately, clone fail will
only happen on counter expression when memory is exhausted.
Fixes: 086f332167 ("netfilter: nf_tables: add clone interface to expression operations")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fetch value and validate u32 netlink attribute. This validation is
usually required when the u32 netlink attributes are being stored in a
field whose size is smaller.
This patch revisits 4da449ae1d ("netfilter: nft_exthdr: Add size check
on u8 nft_exthdr attributes").
Fixes: 96518518cc ("netfilter: add nftables")
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch introduces nft_set_pktinfo_unspec() that ensures proper
initialization all of pktinfo fields for non-IP traffic. This is used
by the bridge, netdev and arp families.
This new function relies on nft_set_pktinfo_proto_unspec() to set a new
tprot_set field that indicates if transport protocol information is
available. Remain fields are zeroed.
The meta expression has been also updated to check to tprot_set in first
place given that zero is a valid tprot value. Even a handcrafted packet
may come with the IPPROTO_RAW (255) protocol number so we can't rely on
this value as tprot unset.
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If the NLM_F_EXCL flag is set, then new elements that clash with an
existing one return EEXIST. In case you try to add an element whose
data area differs from what we have, then this returns EBUSY. If no
flag is specified at all, then this returns success to userspace.
This patch also update the set insert operation so we can fetch the
existing element that clashes with the one you want to add, we need
this to make sure the element data doesn't differ.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We can pass the netns pointer as parameter to the functions that need to
gain access to it. From basechains, I didn't find any client for this
field anymore so let's remove this too.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next,
they are:
1) Don't use userspace datatypes in bridge netfilter code, from
Tobin Harding.
2) Iterate only once over the expectation table when removing the
helper module, instead of once per-netns, from Florian Westphal.
3) Extra sanitization in xt_hook_ops_alloc() to return error in case
we ever pass zero hooks, xt_hook_ops_alloc():
4) Handle NFPROTO_INET from the logging core infrastructure, from
Liping Zhang.
5) Autoload loggers when TRACE target is used from rules, this doesn't
change the behaviour in case the user already selected nfnetlink_log
as preferred way to print tracing logs, also from Liping Zhang.
6) Conntrack slabs with SLAB_HWCACHE_ALIGN to allow rearranging fields
by cache lines, increases the size of entries in 11% per entry.
From Florian Westphal.
7) Skip zone comparison if CONFIG_NF_CONNTRACK_ZONES=n, from Florian.
8) Remove useless defensive check in nf_logger_find_get() from Shivani
Bhardwaj.
9) Remove zone extension as place it in the conntrack object, this is
always include in the hashing and we expect more intensive use of
zones since containers are in place. Also from Florian Westphal.
10) Owner match now works from any namespace, from Eric Bierdeman.
11) Make sure we only reply with TCP reset to TCP traffic from
nf_reject_ipv4, patch from Liping Zhang.
12) Introduce --nflog-size to indicate amount of network packet bytes
that are copied to userspace via log message, from Vishwanath Pai.
This obsoletes --nflog-range that has never worked, it was designed
to achieve this but it has never worked.
13) Introduce generic macros for nf_tables object generation masks.
14) Use generation mask in table, chain and set objects in nf_tables.
This allows fixes interferences with ongoing preparation phase of
the commit protocol and object listings going on at the same time.
This update is introduced in three patches, one per object.
15) Check if the object is active in the next generation for element
deactivation in the rbtree implementation, given that deactivation
happens from the commit phase path we have to observe the future
status of the object.
16) Support for deletion of just added elements in the hash set type.
17) Allow to resize hashtable from /proc entry, not only from the
obscure /sys entry that maps to the module parameter, from Florian
Westphal.
18) Get rid of NFT_BASECHAIN_DISABLED, this code is not exercised
anymore since we tear down the ruleset whenever the netdevice
goes away.
19) Support for matching inverted set lookups, from Arturo Borrero.
20) Simplify the iptables_mangle_hook() by removing a superfluous
extra branch.
21) Introduce ether_addr_equal_masked() and use it from the netfilter
codebase, from Joe Perches.
22) Remove references to "Use netfilter MARK value as routing key"
from the Netfilter Kconfig description given that this toggle
doesn't exists already for 10 years, from Moritz Sichert.
23) Introduce generic NF_INVF() and use it from the xtables codebase,
from Joe Perches.
24) Setting logger to NONE via /proc was not working unless explicit
nul-termination was included in the string. This fixes seems to
leave the former behaviour there, so we don't break backward.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This flag was introduced to restore rulesets from the new netdev
family, but since 5ebe0b0eec ("netfilter: nf_tables: destroy
basechain and rules on netdevice removal") the ruleset is released
once the netdev is gone.
This also removes nft_register_basechain() and
nft_unregister_basechain() since they have no clients anymore after
this rework.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch addresses two problems:
1) The netlink dump is inconsistent when interfering with an ongoing
transaction update for several reasons:
1.a) We don't honor the internal NFT_TABLE_INACTIVE flag, and we should
be skipping these inactive objects in the dump.
1.b) We perform speculative deletion during the preparation phase, that
may result in skipping active objects.
1.c) The listing order changes, which generates noise when tracking
incremental ruleset update via tools like git or our own
testsuite.
2) We don't allow to add and to update the object in the same batch,
eg. add table x; add table x { flags dormant\; }.
In order to resolve these problems:
1) If the user requests a deletion, the object becomes inactive in the
next generation. Then, ignore objects that scheduled to be deleted
from the lookup path, as they will be effectively removed in the
next generation.
2) From the get/dump path, if the object is not currently active, we
skip it.
3) Support 'add X -> update X' sequence from a transaction.
After this update, we obtain a consistent list as long as we stay
in the same generation. The userspace side can detect interferences
through the generation counter so it can restart the dumping.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thus, we can reuse these to check the genmask of any object type, not
only rules. This is required now that tables, chain and sets will get a
generation mask field too in follow up patches.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Liping Zhang says:
"Users may add such a wrong nft rules successfully, which will cause an
endless jump loop:
# nft add rule filter test tcp dport vmap {1: jump test}
This is because before we commit, the element in the current anonymous
set is inactive, so osp->walk will skip this element and miss the
validate check."
To resolve this problem, this patch passes the generation mask to the
walk function through the iter container structure depending on the code
path:
1) If we're dumping the elements, then we have to check if the element
is active in the current generation. Thus, we check for the current
bit in the genmask.
2) If we're checking for loops, then we have to check if the element is
active in the next generation, as we're in the middle of a
transaction. Thus, we check for the next bit in the genmask.
Based on original patch from Liping Zhang.
Reported-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tested-by: Liping Zhang <liping.zhang@spreadtrum.com>
Currently, we support set names of up to 16 bytes, get this aligned
with the maximum length we can use in ipset to make it easier when
considering migration to nf_tables.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
User data is stored at after 'nft_set_ops' private data into 'data[]'
flexible array. The field 'udata' points to user data and 'udlen' stores
its length.
Add new flag NFTA_SET_USERDATA.
Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If the netdevice is destroyed, the resources that are attached should
be released too as they belong to the device that is now gone.
Suggested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We have to release the existing objects on netns removal otherwise we
leak them. Chains are unregistered in first place to make sure no
packets are walking on our rules and sets anymore.
The object release happens by when we unregister the family via
nft_release_afinfo() which is called from nft_unregister_afinfo() from
the corresponding __net_exit path in every family.
Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft monitor mode can then decode and display this trace data.
Parts of LL/Network/Transport headers are provided as separate
attributes.
Otherwise, printing IP address data becomes virtually impossible
for userspace since in the case of the netdev family we really don't
want userspace to have to know all the possible link layer types
and/or sizes just to display/print an ip address.
We also don't want userspace to have to follow ipv6 header chains
to get the s/dport info, the kernel already did this work for us.
To avoid bloating nft_do_chain all data required for tracing is
encapsulated in nft_traceinfo.
The structure is initialized unconditionally(!) for each nft_do_chain
invocation.
This unconditionall call will be moved under a static key in a
followup patch.
With lots of help from Patrick McHardy and Pablo Neira.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Patrick McHardy <kaber@trash.net>
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>
Only pass the void *priv parameter out of the nf_hook_ops. That is
all any of the functions are interested now, and by limiting what is
passed it becomes simpler to change implementation details.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_pktinfo is passed on the stack so this does not bloat any in core
data structures.
By centrally computing this information this makes maintence of the code
simpler, and understading of the code easier.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
As xt_action_param lives on the stack this does not bloat any
persistent data structures.
This is a first step in making netfilter code that needs to know
which network namespace it is executing in simpler.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
- Add nft_pktinfo.pf to replace ops->pf
- Add nft_pktinfo.hook to replace ops->hooknum
This simplifies the code, makes it more readable, and likely reduces
cache line misses. Maintainability is enhanced as the details of
nft_hook_ops are of no concern to the recpients of nft_pktinfo.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_type_to_reg() needs to return the register in the new 32 bit addressing,
otherwise we hit EINVAL when using mappings.
Fixes: 49499c3 ("netfilter: nf_tables: switch registers to 32 bit addressing")
Reported-by: Andreas Schultz <aschultz@tpip.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In case the net_device is gone, we have to unregister the hooks and put back
the reference on the net_device object. Once it comes back, register them
again. This also covers the device rename case.
This patch also adds a new flag to indicate that the basechain is disabled, so
their hooks are not registered. This flag is used by the netdev family to
handle the case where the net_device object is gone. Currently this flag is not
exposed to userspace.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The device is part of the hook configuration, so instead of a global
configuration per table, set it to each of the basechain that we create.
This patch reworks ebddf1a8d7 ("netfilter: nf_tables: allow to bind table to
net_device").
Note that this adds a dev_name field in the nft_base_chain structure which is
required the netdev notification subscription that follows up in a patch to
handle gone net_devices.
Suggested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the internal NFT_AF_NEEDS_DEV flag to indicate that you must
attach this table to a net_device.
This change is required by the follow up patch that introduces the new netdev
table.
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>
Preparation to attach expressions to set elements: add a set extension
type to hold an expression and dump the expression information with the
set element.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add helper functions for initializing, cloning, dumping and destroying
a single expression that is not part of a rule.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch changes sets to support variable sized set element keys / data
up to 64 bytes each by using variable sized set extensions. This allows
to use concatenations with bigger data items suchs as IPv6 addresses.
As a side effect, small keys/data now don't require the full 16 bytes
of struct nft_data anymore but just the space they need.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a size argument to nft_data_init() and pass in the available space.
This will be used by the following patches to support variable sized
set element data.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Switch the nf_tables registers from 128 bit addressing to 32 bit
addressing to support so called concatenations, where multiple values
can be concatenated over multiple registers for O(1) exact matches of
multiple dimensions using sets.
The old register values are mapped to areas of 128 bits for compatibility.
When dumping register numbers, values are expressed using the old values
if they refer to the beginning of a 128 bit area for compatibility.
To support concatenations, register loads of less than a full 32 bit
value need to be padded. This mainly affects the payload and exthdr
expressions, which both unconditionally zero the last word before
copying the data.
Userspace fully passes the testsuite using both old and new register
addressing.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add helper functions to parse and dump register values in netlink attributes.
These helpers will later be changed to take care of translation between the
old 128 bit and the new 32 bit register numbers.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Simple conversion to use u32 pointers to the beginning of the data
area to keep follow up patches smaller.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Only needlessly complicates things due to requiring specific argument
types. Use memcmp directly.
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>
Change nft_validate_input_register() to not only validate the input
register number, but also the length of the load, and rename it to
nft_validate_register_load() to reflect that change.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
All users of nft_validate_register_store() first invoke
nft_validate_output_register(). There is in fact no use for using it
on its own, so simplify the code by folding the functionality into
nft_validate_register_store() and kill it.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The existing name is ambiguous, data is loaded as well when we read from
a register. Rename to nft_validate_register_store() for clarity and
consistency with the upcoming patch to introduce its counterpart,
nft_validate_register_load().
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For values spanning multiple registers, we need to validate that enough
space is available from the destination register onwards. Add a len
argument to nft_validate_data_load() and consolidate the existing length
validations in preparation of that.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add an userdata set extension and allow the user to attach arbitrary
data to set elements. This is intended to hold TLV encoded data like
comments or DNS annotations that have no meaning to the kernel.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a new "dynset" expression for dynamic set updates.
A new set op ->update() is added which, for non existant elements,
invokes an initialization callback and inserts the new element.
For both new or existing elements the extenstion pointer is returned
to the caller to optionally perform timer updates or other actions.
Element removal is not supported so far, however that seems to be a
rather exotic need and can be added later on.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently a set binding is assumed to be related to a lookup and, in
case of maps, a data load.
In order to use bindings for set updates, the loop detection checks
must be restricted to map operations only. Add a flags member to the
binding struct to hold the set "action" flags such as NFT_SET_MAP,
and perform loop detection based on these.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use atomic operations for the element count to avoid races with async
updates.
To properly handle the transactional semantics during netlink updates,
deleted but not yet committed elements are accounted for seperately and
are treated as being already removed. This means for the duration of
a netlink transaction, the limit might be exceeded by the amount of
elements deleted. Set implementations must be prepared to handle this.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add support for element timeouts to nft_hash. The lookup and walking
functions are changed to ignore timed out elements, a periodic garbage
collection task cleans out expired entries.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
GC is expected to happen asynchrously to the netlink interface. In the
netlink path, both insertion and removal of elements consist of two
steps, insertion followed by activation or deactivation followed by
removal, during which the element must not be freed by GC.
The synchronization helpers use an unused bit in the genmask field to
atomically mark an element as "busy", meaning it is either currently
being handled through the netlink API or by GC.
Elements being processed by GC will never survive, netlink will simply
ignore them. Elements being currently processed through netlink will be
skipped by GC and reprocessed during the next run.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add helpers for GC batch destruction: since element destruction needs
a RCU grace period for all set implementations, add some helper functions
for asynchronous batch destruction. Elements are collected in a batch
structure, which is asynchronously released using RCU once its full.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add API support for set element timeouts. Elements can have a individual
timeout value specified, overriding the sets' default.
Two new extension types are used for timeouts - the timeout value and
the expiration time. The timeout value only exists if it differs from
the default value.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add set timeout support to the netlink API. Sets with timeout support
enabled can have a default timeout value and garbage collection interval
specified.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Set elements are the last object type not supporting transaction support.
Implement similar to the existing rule transactions:
The global transaction counter keeps track of two generations, current
and next. Each element contains a bitmask specifying in which generations
it is inactive.
New elements start out as inactive in the current generation and active
in the next. On commit, the previous next generation becomes the current
generation and the element becomes active. The bitmask is then cleared
to indicate that the element is active in all future generations. If the
transaction is aborted, the element is removed from the set before it
becomes active.
When removing an element, it gets marked as inactive in the next generation.
On commit the next generation becomes active and the therefor the element
inactive. It is then taken out of then set and released. On abort, the
element is marked as active for the next generation again.
Lookups ignore elements not active in the current generation.
The current set types (hash/rbtree) both use a field in the extension area
to store the generation mask. This (currently) does not require any
additional memory since we have some free space in there.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add some helper functions for building the genmask as preparation for
set transactions.
Also add a little documentation how this stuff actually works.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Return the extension area from the ->lookup() function to allow to
consolidate common actions.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With the conversion to set extensions, it is now possible to consolidate
the different set element destruction functions.
The set implementations' ->remove() functions are changed to only take
the element out of their internal data structures. Elements will be freed
in a batched fashion after the global transaction's completion RCU grace
period.
This reduces the amount of grace periods required for nft_hash from N
to zero additional ones, additionally this guarantees that the set
elements' extensions of all implementations can be used under RCU
protection.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The set implementations' private struct will only contain the elements
needed to maintain the search structure, all other elements are moved
to the set extensions.
Element allocation and initialization is performed centrally by
nf_tables_api instead of by the different set implementations'
->insert() functions. A new "elemsize" member in the set ops specifies
the amount of memory to reserve for internal usage. Destruction
will also be moved out of the set implementations by a following patch.
Except for element allocation, the patch is a simple conversion to
using data from the extension area.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add simple set extension infrastructure for maintaining variable sized
and optional per element data.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The network namespace is only needed for base chains to get at the
gencursor. Also convert to possible_net_t.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/net/ethernet/cadence/macb.c
Overlapping changes in macb driver, mostly fixes and cleanups
in 'net' overlapping with the integration of at91_ether into
macb in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
The transaction related definitions are squeezed in between the rule
and expression definitions, which are closely related and should be
next to each other. The transaction definitions actually don't belong
into that file at all since it defines the global objects and API and
transactions are internal to nf_tables_api, but for now simply move
them to a seperate section.
Similar, the chain types are in between a set of registration functions,
they belong to the chain section.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The NFT_USERDATA_MAXLEN is defined to 256, however we only have a u8
to store its size. Introduce a struct nft_userdata which contains a
length field and indicate its presence using a single bit in the rule.
The length field of struct nft_userdata is also a u8, however we don't
store zero sized data, so the actual length is udata->len + 1.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The user can crash the kernel if it uses any of the existing NAT
expressions from the wrong hook, so add some code to validate this
when loading the rule.
This patch introduces nft_chain_validate_hooks() which is based on
an existing function in the bridge version of the reject expression.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The existing xtables matches and targets, when used from nft_compat, may
sleep from the destroy path, ie. when removing rules. Since the objects
are released via call_rcu from softirq context, this results in lockdep
splats and possible lockups that may be hard to reproduce.
Patrick also indicated that delayed object release via call_rcu can
cause us problems in the ordering of event notifications when anonymous
sets are in place.
So, this patch restores the synchronous object release from the commit
and abort paths. This includes a call to synchronize_rcu() to make sure
that no packets are walking on the objects that are going to be
released. This is slowier though, but it's simple and it resolves the
aforementioned problems.
This is a partial revert of c7c32e7 ("netfilter: nf_tables: defer all
object release via rcu") that was introduced in 3.16 to speed up
interaction with userspace.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This adds the missing validation code to avoid the use of nat/masq from
non-nat chains. The validation assumes two possible configuration
scenarios:
1) Use of nat from base chain that is not of nat type. Reject this
configuration from the nft_*_init() path of the expression.
2) Use of nat from non-base chain. In this case, we have to wait until
the non-base chain is referenced by at least one base chain via
jump/goto. This is resolved from the nft_*_validate() path which is
called from nf_tables_check_loops().
The user gets an -EOPNOTSUPP in both cases.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We want to know in which cases the user explicitly sets the policy
options. In that case, we also want to dump back the info.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use generic u64_stats_sync infrastructure to get proper 64bit stats,
even on 32bit arches, at no extra cost for 64bit arches.
Without this fix, 32bit arches can have some wrong counters at the time
the carry is propagated into upper word.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since 4fefee5 ("netfilter: nf_tables: allow to delete several objects
from a batch"), every new rule bumps the chain use counter. However,
this is limited to 16 bits, which means that it will overrun after
2^16 rules.
Use a u32 chain counter and check for overflows (just like we do for
table objects).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that all objects are released in the reverse order via the
transaction infrastructure, we can enqueue the release via
call_rcu to save one synchronize_rcu. For small rule-sets loaded
via nft -f, it now takes around 50ms less here.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of caching the original skbuff that contains the netlink
messages, this stores the netlink message sequence number, the
netlink portID and the report flag. This helps to prepare the
introduction of the object release via call_rcu.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Leave the set content in consistent state if we fail to load the
batch. Use the new generic transaction infrastructure to achieve
this.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch speeds up rule-set updates and it also provides a way
to revert updates and leave things in consistent state in case that
the batch needs to be aborted.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch speeds up rule-set updates and it also introduces a way to
revert chain updates if the batch is aborted. The idea is to store the
changes in the transaction to apply that in the commit step.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch reworks the nf_tables API so set updates are included in
the same batch that contains rule updates. This speeds up rule-set
updates since we skip a dialog of four messages between kernel and
user-space (two on each direction), from:
1) create the set and send netlink message to the kernel
2) process the response from the kernel that contains the allocated name.
3) add the set elements and send netlink message to the kernel.
4) process the response from the kernel (to check for errors).
To:
1) add the set to the batch.
2) add the set elements to the batch.
3) add the rule that points to the set.
4) send batch to the kernel.
This also introduces an internal set ID (NFTA_SET_ID) that is unique
in the batch so set elements and rules can refer to new sets.
Backward compatibility has been only retained in userspace, this
means that new nft versions can talk to the kernel both in the new
and the old fashion.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The patch adds message type to the transaction to simplify the
commit the and abort routines. Yet another step forward in the
generalisation of the transaction infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch generalises the existing rule transaction infrastructure
so it can be used to handle set, table and chain object transactions
as well. The transaction provides a data area that stores private
information depending on the transaction type.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The new transaction infrastructure updates the family, table and chain
objects in the context structure, so let's deconstify them. While at it,
move the context structure initialization routine to the top of the
source file as it will be also used from the table and chain routines.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The current set selection simply choses the first set type that provides
the requested features, which always results in the rbtree being chosen
by virtue of being the first set in the list.
What we actually want to do is choose the implementation that can provide
the requested features and is optimal from either a performance or memory
perspective depending on the characteristics of the elements and the
preferences specified by the user.
The elements are not known when creating a set. Even if we would provide
them for anonymous (literal) sets, we'd still have standalone sets where
the elements are not known in advance. We therefore need an abstract
description of the data charcteristics.
The kernel already knows the size of the key, this patch starts by
introducing a nested set description which so far contains only the maximum
amount of elements. Based on this the set implementations are changed to
provide an estimate of the required amount of memory and the lookup
complexity class.
The set ops have a new callback ->estimate() that is invoked during set
selection. It receives a structure containing the attributes known to the
kernel and is supposed to populate a struct nft_set_estimate with the
complexity class and, in case the size is known, the complete amount of
memory required, or the amount of memory required per element otherwise.
Based on the policy specified by the user (performance/memory, defaulting
to performance) the kernel will then select the best suited implementation.
Even if the set implementation would allow to add more than the specified
maximum amount of elements, they are enforced since new implementations
might not be able to add more than maximum based on which they were
selected.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In order to fix set destruction notifications and get rid of unnecessary
members in private data structures, pass the context to expressions'
destructor functions again.
In order to do so, replace various members in the nft_rule_trans structure
by the full context.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This allows us to store user comment strings, but it could be also
used to store any kind of information that the user application needs
to link to the rule.
Scratch 8 bits for the new ulen field that indicates the length the
user data area. 4 bits from the handle (so it's 42 bits long, according
to Patrick, it would last 139 years with 1000 new rules per second)
and 4 bits from dlen (so the expression data area is 4K, which seems
sufficient by now even considering the compatibility layer).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
We may lost race if we flush the rule-set (which happens asynchronously
via call_rcu) and we try to remove the table (that userspace assumes
to be empty).
Fix this by recovering synchronous rule and chain deletion. This was
introduced time ago before we had no batch support, and synchronous
rule deletion performance was not good. Now that we have the batch
support, we can just postpone the purge of old rule in a second step
in the commit phase. All object deletions are synchronous after this
patch.
As a side effect, we save memory as we don't need rcu_head per rule
anymore.
Cc: Patrick McHardy <kaber@trash.net>
Reported-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For the reject module, we need to add AF-specific implementations to
get rid of incorrect module dependencies. Try to load an AF-specific
module first and fall back to generic modules.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We don't encode argument types into function names and since besides
nft_do_chain() there are only AF-specific versions, there is no risk
of confusion.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Minor nf_chain_type cleanups:
- reorder struct to plug a hoe
- rename struct module member to "owner" for consistency
- rename nf_hookfn array to "hooks" for consistency
- reorder initializers for better readability
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The chain type module reference handling makes no sense at all: we take
a reference immediately when the module is registered, preventing the
module from ever being unloaded.
Fix by taking a reference when we're actually creating a chain of the
chain type and release the reference when destroying the chain.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For L3-proto independant rules we need to get at the L4 protocol value
directly. Add it to the nft_pktinfo struct and use the meta expression
to retrieve it.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add support to register chains to multiple hooks for different address
families for mixed IPv4/IPv6 tables.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Multi-family tables need the AF from the hook ops. Add a pointer to the
hook ops and replace usage of the hooknum member in struct nft_pktinfo.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.
Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for tracing the packet travel through
the ruleset, in a similar fashion to x_tables.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds a batch support to nfnetlink. Basically, it adds
two new control messages:
* NFNL_MSG_BATCH_BEGIN, that indicates the beginning of a batch,
the nfgenmsg->res_id indicates the nfnetlink subsystem ID.
* NFNL_MSG_BATCH_END, that results in the invocation of the
ss->commit callback function. If not specified or an error
ocurred in the batch, the ss->abort function is invoked
instead.
The end message represents the commit operation in nftables, the
lack of end message results in an abort. This patch also adds the
.call_batch function that is only called from the batch receival
path.
This patch adds atomic rule updates and dumps based on
bitmask generations. This allows to atomically commit a set of
rule-set updates incrementally without altering the internal
state of existing nf_tables expressions/matches/targets.
The idea consists of using a generation cursor of 1 bit and
a bitmask of 2 bits per rule. Assuming the gencursor is 0,
then the genmask (expressed as a bitmask) can be interpreted
as:
00 active in the present, will be active in the next generation.
01 inactive in the present, will be active in the next generation.
10 active in the present, will be deleted in the next generation.
^
gencursor
Once you invoke the transition to the next generation, the global
gencursor is updated:
00 active in the present, will be active in the next generation.
01 active in the present, needs to zero its future, it becomes 00.
10 inactive in the present, delete now.
^
gencursor
If a dump is in progress and nf_tables enters a new generation,
the dump will stop and return -EBUSY to let userspace know that
it has to retry again. In order to invalidate dumps, a global
genctr counter is increased everytime nf_tables enters a new
generation.
This new operation can be used from the user-space utility
that controls the firewall, eg.
nft -f restore
The rule updates contained in `file' will be applied atomically.
cat file
-----
add filter INPUT ip saddr 1.1.1.1 counter accept #1
del filter INPUT ip daddr 2.2.2.2 counter drop #2
-EOF-
Note that the rule 1 will be inactive until the transition to the
next generation, the rule 2 will be evicted in the next generation.
There is a penalty during the rule update due to the branch
misprediction in the packet matching framework. But that should be
quickly resolved once the iteration over the commit list that
contain rules that require updates is finished.
Event notification happens once the rule-set update has been
committed. So we skip notifications is case the rule-set update
is aborted, which can happen in case that the rule-set is tested
to apply correctly.
This patch squashed the following patches from Pablo:
* nf_tables: atomic rule updates and dumps
* nf_tables: get rid of per rule list_head for commits
* nf_tables: use per netns commit list
* nfnetlink: add batch support and use it from nf_tables
* nf_tables: all rule updates are transactional
* nf_tables: attach replacement rule after stale one
* nf_tables: do not allow deletion/replacement of stale rules
* nf_tables: remove unused NFTA_RULE_FLAGS
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Register family per netnamespace to ensure that sets are
only visible in its approapriate namespace.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the x_tables compatibility layer. This allows you
to use existing x_tables matches and targets from nf_tables.
This compatibility later allows us to use existing matches/targets
for features that are still missing in nf_tables. We can progressively
replace them with native nf_tables extensions. It also provides the
userspace compatibility software that allows you to express the
rule-set using the iptables syntax but using the nf_tables kernel
components.
In order to get this compatibility layer working, I've done the
following things:
* add NFNL_SUBSYS_NFT_COMPAT: this new nfnetlink subsystem is used
to query the x_tables match/target revision, so we don't need to
use the native x_table getsockopt interface.
* emulate xt structures: this required extending the struct nft_pktinfo
to include the fragment offset, which is already obtained from
ip[6]_tables and that is used by some matches/targets.
* add support for default policy to base chains, required to emulate
x_tables.
* add NFTA_CHAIN_USE attribute to obtain the number of references to
chains, required by x_tables emulation.
* add chain packet/byte counters using per-cpu.
* support 32-64 bits compat.
For historical reasons, this patch includes the following patches
that were posted in the netfilter-devel mailing list.
From Pablo Neira Ayuso:
* nf_tables: add default policy to base chains
* netfilter: nf_tables: add NFTA_CHAIN_USE attribute
* nf_tables: nft_compat: private data of target and matches in contiguous area
* nf_tables: validate hooks for compat match/target
* nf_tables: nft_compat: release cached matches/targets
* nf_tables: x_tables support as a compile time option
* nf_tables: fix alias for xtables over nftables module
* nf_tables: add packet and byte counters per chain
* nf_tables: fix per-chain counter stats if no counters are passed
* nf_tables: don't bump chain stats
* nf_tables: add protocol and flags for xtables over nf_tables
* nf_tables: add ip[6]t_entry emulation
* nf_tables: move specific layer 3 compat code to nf_tables_ipv[4|6]
* nf_tables: support 32bits-64bits x_tables compat
* nf_tables: fix compilation if CONFIG_COMPAT is disabled
From Patrick McHardy:
* nf_tables: move policy to struct nft_base_chain
* nf_tables: send notifications for base chain policy changes
From Alexander Primak:
* nf_tables: remove the duplicate NF_INET_LOCAL_OUT
From Nicolas Dichtel:
* nf_tables: fix compilation when nf-netlink is a module
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch converts built-in tables/chains to chain types that
allows you to deploy customized table and chain configurations from
userspace.
After this patch, you have to specify the chain type when
creating a new chain:
add chain ip filter output { type filter hook input priority 0; }
^^^^ ------
The existing chain types after this patch are: filter, route and
nat. Note that tables are just containers of chains with no specific
semantics, which is a significant change with regards to iptables.
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 the new netlink API for maintaining nf_tables sets
independently of the ruleset. The API supports the following operations:
- creation of sets
- deletion of sets
- querying of specific sets
- dumping of all sets
- addition of set elements
- removal of set elements
- dumping of all set elements
Sets are identified by name, each table defines an individual namespace.
The name of a set may be allocated automatically, this is mostly useful
in combination with the NFT_SET_ANONYMOUS flag, which destroys a set
automatically once the last reference has been released.
Sets can be marked constant, meaning they're not allowed to change while
linked to a rule. This allows to perform lockless operation for set
types that would otherwise require locking.
Additionally, if the implementation supports it, sets can (as before) be
used as maps, associating a data value with each key (or range), by
specifying the NFT_SET_MAP flag and can be used for interval queries by
specifying the NFT_SET_INTERVAL flag.
Set elements are added and removed incrementally. All element operations
support batching, reducing netlink message and set lookup overhead.
The old "set" and "hash" expressions are replaced by a generic "lookup"
expression, which binds to the specified set. Userspace is not aware
of the actual set implementation used by the kernel anymore, all
configuration options are generic.
Currently the implementation selection logic is largely missing and the
kernel will simply use the first registered implementation supporting the
requested operation. Eventually, the plan is to have userspace supply a
description of the data characteristics and select the implementation
based on expected performance and memory use.
This patch includes the new 'lookup' expression to look up for element
matching in the set.
This patch includes kernel-doc descriptions for this set API and it
also includes the following fixes.
From Patrick McHardy:
* netfilter: nf_tables: fix set element data type in dumps
* netfilter: nf_tables: fix indentation of struct nft_set_elem comments
* netfilter: nf_tables: fix oops in nft_validate_data_load()
* netfilter: nf_tables: fix oops while listing sets of built-in tables
* netfilter: nf_tables: destroy anonymous sets immediately if binding fails
* netfilter: nf_tables: propagate context to set iter callback
* netfilter: nf_tables: add loop detection
From Pablo Neira Ayuso:
* netfilter: nf_tables: allow to dump all existing sets
* netfilter: nf_tables: fix wrong type for flags variable in newelem
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>