Stateful network admission policy may allow connections to one
direction and reject connections initiated in the other direction.
After policy change it is possible that for a new connection an
overlapping conntrack entry already exists, where the original
direction of the existing connection is opposed to the new
connection's initial packet.
Most importantly, conntrack state relating to the current packet gets
the "reply" designation based on whether the original direction tuple
or the reply direction tuple matched. If this "directionality" is
wrong w.r.t. to the stateful network admission policy it may happen
that packets in neither direction are correctly admitted.
This patch adds a new "force commit" option to the OVS conntrack
action that checks the original direction of an existing conntrack
entry. If that direction is opposed to the current packet, the
existing conntrack entry is deleted and a new one is subsequently
created in the correct direction.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the fields of the conntrack original direction 5-tuple to struct
sw_flow_key. The new fields are initially marked as non-existent, and
are populated whenever a conntrack action is executed and either finds
or generates a conntrack entry. This means that these fields exist
for all packets that were not rejected by conntrack as untrackable.
The original tuple fields in the sw_flow_key are filled from the
original direction tuple of the conntrack entry relating to the
current packet, or from the original direction tuple of the master
conntrack entry, if the current conntrack entry has a master.
Generally, expected connections of connections having an assigned
helper (e.g., FTP), have a master conntrack entry.
The main purpose of the new conntrack original tuple fields is to
allow matching on them for policy decision purposes, with the premise
that the admissibility of tracked connections reply packets (as well
as original direction packets), and both direction packets of any
related connections may be based on ACL rules applying to the master
connection's original direction 5-tuple. This also makes it easier to
make policy decisions when the actual packet headers might have been
transformed by NAT, as the original direction 5-tuple represents the
packet headers before any such transformation.
When using the original direction 5-tuple the admissibility of return
and/or related packets need not be based on the mere existence of a
conntrack entry, allowing separation of admission policy from the
established conntrack state. While existence of a conntrack entry is
required for admission of the return or related packets, policy
changes can render connections that were initially admitted to be
rejected or dropped afterwards. If the admission of the return and
related packets was based on mere conntrack state (e.g., connection
being in an established state), a policy change that would make the
connection rejected or dropped would need to find and delete all
conntrack entries affected by such a change. When using the original
direction 5-tuple matching the affected conntrack entries can be
allowed to time out instead, as the established state of the
connection would not need to be the basis for packet admission any
more.
It should be noted that the directionality of related connections may
be the same or different than that of the master connection, and
neither the original direction 5-tuple nor the conntrack state bits
carry this information. If needed, the directionality of the master
connection can be stored in master's conntrack mark or labels, which
are automatically inherited by the expected related connections.
The fact that neither ARP nor ND packets are trackable by conntrack
allows mutual exclusion between ARP/ND and the new conntrack original
tuple fields. Hence, the IP addresses are overlaid in union with ARP
and ND fields. This allows the sw_flow_key to not grow much due to
this patch, but it also means that we must be careful to never use the
new key fields with ARP or ND packets. ARP is easy to distinguish and
keep mutually exclusive based on the ethernet type, but ND being an
ICMPv6 protocol requires a bit more attention.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We avoid calling into nf_conntrack_in() for expected connections, as
that would remove the expectation that we want to stick around until
we are ready to commit the connection. Instead, we do a lookup in the
expectation table directly. However, after a successful expectation
lookup we have set the flow key label field from the master
connection, whereas nf_conntrack_in() does not do this. This leads to
master's labels being inherited after an expectation lookup, but those
labels not being inherited after the corresponding conntrack action
with a commit flag.
This patch resolves the problem by changing the commit code path to
also inherit the master's labels to the expected connection.
Resolving this conflict in favor of inheriting the labels allows more
information be passed from the master connection to related
connections, which would otherwise be much harder if the 32 bits in
the connmark are not enough. Labels can still be set explicitly, so
this change only affects the default values of the labels in presense
of a master connection.
Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Refactoring conntrack labels initialization makes changes in later
patches easier to review.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since 23014011ba ("netfilter: conntrack: support a fixed size of 128
distinct labels"), the size of conntrack labels extension has fixed to
128 bits, so we do not need to check for labels sizes shorter than 128
at run-time. This patch simplifies labels length logic accordingly,
but allows the conntrack labels size to be increased in the future
without breaking the build. In the event of conntrack labels
increasing in size OVS would still be able to deal with the 128 first
label bits.
Suggested-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the array of labels in struct ovs_key_ct_label an union, adding a
u32 array of the same byte size as the existing u8 array. It is
faster to loop through the labels 32 bits at the time, which is also
the alignment of netlink attributes.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Receiving change events before the 'new' event for the connection has
been received can be confusing. Avoid triggering change events for
setting conntrack mark or labels before the conntrack entry has been
confirmed.
Fixes: 182e3042e1 ("openvswitch: Allow matching on conntrack mark")
Fixes: c2ac667358 ("openvswitch: Allow matching on conntrack label")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The conntrack lookup for existing connections fails to invert the
packet 5-tuple for NATted packets, and therefore fails to find the
existing conntrack entry. Conntrack only stores 5-tuples for incoming
packets, and there are various situations where a lookup on a packet
that has already been transformed by NAT needs to be made. Looking up
an existing conntrack entry upon executing packet received from the
userspace is one of them.
This patch fixes ovs_ct_find_existing() to invert the packet 5-tuple
for the conntrack lookup whenever the packet has already been
transformed by conntrack from its input form as evidenced by one of
the NAT flags being set in the conntrack state metadata.
Fixes: 05752523e5 ("openvswitch: Interface with NAT.")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix comments referring to skb 'nfct' and 'nfctinfo' fields now that
they are combined into '_nfct'.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for your net-next
tree, they are:
1) Stash ctinfo 3-bit field into pointer to nf_conntrack object from
sk_buff so we only access one single cacheline in the conntrack
hotpath. Patchset from Florian Westphal.
2) Don't leak pointer to internal structures when exporting x_tables
ruleset back to userspace, from Willem DeBruijn. This includes new
helper functions to copy data to userspace such as xt_data_to_user()
as well as conversions of our ip_tables, ip6_tables and arp_tables
clients to use it. Not surprinsingly, ebtables requires an ad-hoc
update. There is also a new field in x_tables extensions to indicate
the amount of bytes that we copy to userspace.
3) Add nf_log_all_netns sysctl: This new knob allows you to enable
logging via nf_log infrastructure for all existing netnamespaces.
Given the effort to provide pernet syslog has been discontinued,
let's provide a way to restore logging using netfilter kernel logging
facilities in trusted environments. Patch from Michal Kubecek.
4) Validate SCTP checksum from conntrack helper, from Davide Caratti.
5) Merge UDPlite conntrack and NAT helpers into UDP, this was mostly
a copy&paste from the original helper, from Florian Westphal.
6) Reset netfilter state when duplicating packets, also from Florian.
7) Remove unnecessary check for broadcast in IPv6 in pkttype match and
nft_meta, from Liping Zhang.
8) Add missing code to deal with loopback packets from nft_meta when
used by the netdev family, also from Liping.
9) Several cleanups on nf_tables, one to remove unnecessary check from
the netlink control plane path to add table, set and stateful objects
and code consolidation when unregister chain hooks, from Gao Feng.
10) Fix harmless reference counter underflow in IPVS that, however,
results in problems with the introduction of the new refcount_t
type, from David Windsor.
11) Enable LIBCRC32C from nf_ct_sctp instead of nf_nat_sctp,
from Davide Caratti.
12) Missing documentation on nf_tables uapi header, from Liping Zhang.
13) Use rb_entry() helper in xt_connlimit, from Geliang Tang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a helper to assign a nf_conn entry and the ctinfo bits to an sk_buff.
This avoids changing code in followup patch that merges skb->nfct and
skb->nfctinfo into skb->_nfct.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Followup patch renames skb->nfct and changes its type so add a helper to
avoid intrusive rename change later.
Signed-off-by: Florian Westphal <fw@strlen.de>
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>
If nf_ct_frag6_gather() returns an error other than -EINPROGRESS, it
means that we still have a reference to the skb. We should free it
before returning from handle_fragments, as stated in the comment above.
Fixes: daaa7d647f ("netfilter: ipv6: avoid nf_iterate recursion")
CC: Florian Westphal <fw@strlen.de>
CC: Pravin B Shelar <pshelar@ovn.org>
CC: Joe Stringer <joe@ovn.org>
Signed-off-by: Daniele Di Proietto <diproiettod@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
NF_REPEAT is only needed from nf_conntrack_in() under a very specific
case required by the TCP protocol tracker, we can handle this case
without returning to the core hook path. Handling of NF_REPEAT from the
nf_reinject() is left untouched.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When an error occurs during conntrack template creation as part of
actions validation, we need to free the template. Previously we've been
using nf_ct_put() to do this, but nf_ct_tmpl_free() is more appropriate.
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
ovs_ct_find_existing() issues a warning if an existing conntrack entry
classified as IP_CT_NEW is found, with the premise that this should
not happen. However, a newly confirmed, non-expected conntrack entry
remains IP_CT_NEW as long as no reply direction traffic is seen. This
has resulted into somewhat confusing kernel log messages. This patch
removes this check and warning.
Fixes: 289f2253 ("openvswitch: Find existing conntrack entry after upcall.")
Suggested-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The conntrack label extension is currently variable-sized, e.g. if
only 2 labels are used by iptables rules then the labels->bits[] array
will only contain one element.
We track size of each label storage area in the 'words' member.
But in nftables and openvswitch we always have to ask for worst-case
since we don't know what bit will be used at configuration time.
As most arches are 64bit we need to allocate 24 bytes in this case:
struct nf_conn_labels {
u8 words; /* 0 1 */
/* XXX 7 bytes hole, try to pack */
long unsigned bits[2]; /* 8 24 */
Make bits a fixed size and drop the words member, it simplifies
the code and only increases memory requirements on x86 when
less than 64bit labels are required.
We still only allocate the extension if its needed.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Several cases of overlapping changes, except the packet scheduler
conflicts which deal with the addition of the free list parameter
to qdisc_enqueue().
Signed-off-by: David S. Miller <davem@davemloft.net>
Only the first and last netlink message for a particular conntrack are
actually sent. The first message is sent through nf_conntrack_confirm when
the conntrack is committed. The last one is sent when the conntrack is
destroyed on timeout. The other conntrack state change messages are not
advertised.
When the conntrack subsystem is used from netfilter, nf_conntrack_confirm
is called for each packet, from the postrouting hook, which in turn calls
nf_ct_deliver_cached_events to send the state change netlink messages.
This commit fixes the problem by calling nf_ct_deliver_cached_events in the
non-commit case as well.
Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
CC: Joe Stringer <joestringer@nicira.com>
CC: Justin Pettit <jpettit@nicira.com>
CC: Andy Zhou <azhou@nicira.com>
CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Samuel Gauthier <samuel.gauthier@6wind.com>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only set conntrack mark or labels when the commit flag is specified.
This makes sure we can not set them before the connection has been
persisted, as in that case the mark and labels would be lost in an
event of an userspace upcall.
OVS userspace already requires the commit flag to accept setting
ct_mark and/or ct_labels. Validate for this in the kernel API.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set conntrack mark and labels right before committing so that
the initial conntrack NEW event has the mark and labels.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The nf_conntrack_core.c fix in 'net' is not relevant in 'net-next'
because we no longer have a per-netns conntrack hash.
The ip_gre.c conflict as well as the iwlwifi ones were cases of
overlapping changes.
Conflicts:
drivers/net/wireless/intel/iwlwifi/mvm/tx.c
net/ipv4/ip_gre.c
net/netfilter/nf_conntrack_core.c
Signed-off-by: David S. Miller <davem@davemloft.net>
When using conntrack helpers from OVS, a common configuration is to
perform a lookup without specifying a helper, then go through a
firewalling policy, only to decide to attach a helper afterwards.
In this case, the initial lookup will cause a ct entry to be attached to
the skb, then the later commit with helper should attach the helper and
confirm the connection. However, the helper attachment has been missing.
If the user has enabled automatic helper attachment, then this issue
will be masked as it will be applied in init_conntrack(). It is also
masked if the action is executed from ovs_packet_cmd_execute() as that
will construct a fresh skb.
This patch fixes the issue by making an explicit call to try to assign
the helper if there is a discrepancy between the action's helper and the
current skb->nfct.
Fixes: cae3a26275 ("openvswitch: Allow attaching helpers to ct action")
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the protocol is not natively supported, this assigns generic protocol
tracker so we can always assume a valid pointer after these calls.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Joe Stringer <joe@ovn.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for your net-next
tree, mostly from Florian Westphal to sort out the lack of sufficient
validation in x_tables and connlabel preparation patches to add
nf_tables support. They are:
1) Ensure we don't go over the ruleset blob boundaries in
mark_source_chains().
2) Validate that target jumps land on an existing xt_entry. This extra
sanitization comes with a performance penalty when loading the ruleset.
3) Introduce xt_check_entry_offsets() and use it from {arp,ip,ip6}tables.
4) Get rid of the smallish check_entry() functions in {arp,ip,ip6}tables.
5) Make sure the minimal possible target size in x_tables.
6) Similar to #3, add xt_compat_check_entry_offsets() for compat code.
7) Check that standard target size is valid.
8) More sanitization to ensure that the target_offset field is correct.
9) Add xt_check_entry_match() to validate that matches are well-formed.
10-12) Three patch to reduce the number of parameters in
translate_compat_table() for {arp,ip,ip6}tables by using a container
structure.
13) No need to return value from xt_compat_match_from_user(), so make
it void.
14) Consolidate translate_table() so it can be used by compat code too.
15) Remove obsolete check for compat code, so we keep consistent with
what was already removed in the native layout code (back in 2007).
16) Get rid of target jump validation from mark_source_chains(),
obsoleted by #2.
17) Introduce xt_copy_counters_from_user() to consolidate counter
copying, and use it from {arp,ip,ip6}tables.
18,22) Get rid of unnecessary explicit inlining in ctnetlink for dump
functions.
19) Move nf_connlabel_match() to xt_connlabel.
20) Skip event notification if connlabel did not change.
21) Update of nf_connlabels_get() to make the upcoming nft connlabel
support easier.
23) Remove spinlock to read protocol state field in conntrack.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
nf_connlabel_set() takes the bit number that we would like to set.
nf_connlabels_get() however took the number of bits that we want to
support.
So e.g. nf_connlabels_get(32) support bits 0 to 31, but not 32.
This changes nf_connlabels_get() to take the highest bit that we want
to set.
Callers then don't have to cope with a potential integer wrap
when using nf_connlabels_get(bit + 1) anymore.
Current callers are fine, this change is only to make folloup
nft ct label set support simpler.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for you net tree,
they are:
1) There was a race condition between parallel save/swap and delete,
which resulted a kernel crash due to the increase ref for save, swap,
wrong ref decrease operations. Reported and fixed by Vishwanath Pai.
2) OVS should call into CT NAT for packets of new expected connections only
when the conntrack state is persisted with the 'commit' option to the
OVS CT action. From Jarno Rajahalme.
3) Resolve kconfig dependencies with new OVS NAT support. From Arnd Bergmann.
4) Early validation of entry->target_offset to make sure it doesn't take us
out from the blob, from Florian Westphal.
5) Again early validation of entry->next_offset to make sure it doesn't take
out from the blob, also from Florian.
6) Check that entry->target_offset is always of of sizeof(struct xt_entry)
for unconditional entries, when checking both from check_underflow()
and when checking for loops in mark_source_chains(), again from
Florian.
7) Fix inconsistent behaviour in nfnetlink_queue when
NFQA_CFG_F_FAIL_OPEN is set and netlink_unicast() fails due to buffer
overrun, we have to reinject the packet as the user expects.
8) Enforce nul-terminated table names from getsockopt GET_ENTRIES
requests.
9) Don't assume skb->sk is set from nft_bridge_reject and synproxy,
this fixes a recent update of the code to namespaceify
ip_default_ttl, patch from Liping Zhang.
This batch comes with four patches to validate x_tables blobs coming
from userspace. CONFIG_USERNS exposes the x_tables interface to
unpriviledged users and to be honest this interface never received the
attention for this move away from the CAP_NET_ADMIN domain. Florian is
working on another round with more patches with more sanity checks, so
expect a bit more Netfilter fixes in this development cycle than usual.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The openvswitch code has gained support for calling into the
nf-nat-ipv4/ipv6 modules, however those can be loadable modules
in a configuration in which openvswitch is built-in, leading
to link errors:
net/built-in.o: In function `__ovs_ct_lookup':
:(.text+0x2cc2c8): undefined reference to `nf_nat_icmp_reply_translation'
:(.text+0x2cc66c): undefined reference to `nf_nat_icmpv6_reply_translation'
The dependency on (!NF_NAT || NF_NAT) prevents similar issues,
but NF_NAT is set to 'y' if any of the symbols selecting
it are built-in, but the link error happens when any of them
are modular.
A second issue is that even if CONFIG_NF_NAT_IPV6 is built-in,
CONFIG_NF_NAT_IPV4 might be completely disabled. This is unlikely
to be useful in practice, but the driver currently only handles
IPv6 being optional.
This patch improves the Kconfig dependency so that openvswitch
cannot be built-in if either of the two other symbols are set
to 'm', and it replaces the incorrect #ifdef in ovs_ct_nat_execute()
with two "if (IS_ENABLED())" checks that should catch all corner
cases also make the code more readable.
The same #ifdef exists ovs_ct_nat_to_attr(), where it does not
cause a link error, but for consistency I'm changing it the same
way.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 05752523e5 ("openvswitch: Interface with NAT.")
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
OVS should call into CT NAT for packets of new expected connections only
when the conntrack state is persisted with the 'commit' option to the
OVS CT action. The test for this condition is doubly wrong, as the CT
status field is ANDed with the bit number (IPS_EXPECTED_BIT) rather
than the mask (IPS_EXPECTED), and due to the wrong assumption that the
expected bit would apply only for the first (i.e., 'new') packet of a
connection, while in fact the expected bit remains on for the lifetime of
an expected connection. The 'ctinfo' value IP_CT_RELATED derived from
the ct status can be used instead, as it is only ever applicable to
the 'new' packets of the expected connection.
Fixes: 05752523e5 ('openvswitch: Interface with NAT.')
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For the input parameter count, it's better to use the size
of destination buffer size, as nla_memcpy would take into
account the length of the source netlink attribute when
a data is copied from an attribute.
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend OVS conntrack interface to cover NAT. New nested
OVS_CT_ATTR_NAT attribute may be used to include NAT with a CT action.
A bare OVS_CT_ATTR_NAT only mangles existing and expected connections.
If OVS_NAT_ATTR_SRC or OVS_NAT_ATTR_DST is included within the nested
attributes, new (non-committed/non-confirmed) connections are mangled
according to the rest of the nested attributes.
The corresponding OVS userspace patch series includes test cases (in
tests/system-traffic.at) that also serve as example uses.
This work extends on a branch by Thomas Graf at
https://github.com/tgraf/ovs/tree/nat.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There is no need to help connections that are not confirmed, so we can
delay helping new connections to the time when they are confirmed.
This change is needed for NAT support, and having this as a separate
patch will make the following NAT patch a bit easier to review.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Repeat the nf_conntrack_in() call when it returns NF_REPEAT. This
avoids dropping a SYN packet re-opening an existing TCP connection.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a new function ovs_ct_find_existing() to find an existing
conntrack entry for which this packet was already applied to. This is
only to be called when there is evidence that the packet was already
tracked and committed, but we lost the ct reference due to an
userspace upcall.
ovs_ct_find_existing() is called from skb_nfct_cached(), which can now
hide the fact that the ct reference may have been lost due to an
upcall. This allows ovs_ct_commit() to be simplified.
This patch is needed by later "openvswitch: Interface with NAT" patch,
as we need to be able to pass the packet through NAT using the
original ct reference also after the reference is lost after an
upcall.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Only a successful nf_conntrack_in() call can effect a connection state
change, so it suffices to update the key only after the
nf_conntrack_in() returns.
This change is needed for the later NAT patches.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This makes the code easier to understand and the following patches
more focused.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Remove the definition of IP_CT_NEW_REPLY from the kernel as it does
not make sense. This allows the definition of IP_CT_NUMBER to be
simplified as well.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Commit 5b48bb8506c5 ("openvswitch: Fix helper reference leak") fixed a
reference leak on helper objects, but inadvertently introduced a leak on
the ct template.
Previously, ct_info.ct->general.use was initialized to 0 by
nf_ct_tmpl_alloc() and only incremented when ovs_ct_copy_action()
returned successful. If an error occurred while adding the helper or
adding the action to the actions buffer, the __ovs_ct_free_action()
cleanup would use nf_ct_put() to free the entry; However, this relies on
atomic_dec_and_test(ct_info.ct->general.use). This reference must be
incremented first, or nf_ct_put() will never free it.
Fix the issue by acquiring a reference to the template immediately after
allocation.
Fixes: cae3a26275 ("openvswitch: Allow attaching helpers to ct action")
Fixes: 5b48bb8506c5 ("openvswitch: Fix helper reference leak")
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains the first batch of Netfilter updates for
the upcoming 4.5 kernel. This batch contains userspace netfilter header
compilation fixes, support for packet mangling in nf_tables, the new
tracing infrastructure for nf_tables and cgroup2 support for iptables.
More specifically, they are:
1) Two patches to include dependencies in our netfilter userspace
headers to resolve compilation problems, from Mikko Rapeli.
2) Four comestic cleanup patches for the ebtables codebase, from Ian Morris.
3) Remove duplicate include in the netfilter reject infrastructure,
from Stephen Hemminger.
4) Two patches to simplify the netfilter defragmentation code for IPv6,
patch from Florian Westphal.
5) Fix root ownership of /proc/net netfilter for unpriviledged net
namespaces, from Philip Whineray.
6) Get rid of unused fields in struct nft_pktinfo, from Florian Westphal.
7) Add mangling support to our nf_tables payload expression, from
Patrick McHardy.
8) Introduce a new netlink-based tracing infrastructure for nf_tables,
from Florian Westphal.
9) Change setter functions in nfnetlink_log to be void, from
Rami Rosen.
10) Add netns support to the cttimeout infrastructure.
11) Add cgroup2 support to iptables, from Tejun Heo.
12) Introduce nfnl_dereference_protected() in nfnetlink, from Florian.
13) Add support for mangling pkttype in the nf_tables meta expression,
also from Florian.
BTW, I need that you pull net into net-next, I have another batch that
requires changes that I don't yet see in net.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If userspace executes ct(zone=1), and the connection tracker determines
that the packet is invalid, then the ct_zone flow key field is populated
with the default zone rather than the zone that was specified. Even
though connection tracking failed, this field should be updated with the
value that the action specified. Fix the issue.
Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the actions (re)allocation fails, or the actions list is larger than the
maximum size, and the conntrack action is the last action when these
problems are hit, then references to helper modules may be leaked. Fix
the issue.
Fixes: cae3a26275 ("openvswitch: Allow attaching helpers to ct action")
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The previous patch changed nf_ct_frag6_gather() to morph reassembled skb
with the previous one.
This means that the return value is always NULL or the skb argument.
So change it to an err value.
Instead of invoking NF_HOOK recursively with threshold to skip already-called hooks
we can now just return NF_ACCEPT to move on to the next hook except for
-EINPROGRESS (which means skb has been queued for reassembly), in which case we
return NF_STOLEN.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
commit 6aafeef03b
("netfilter: push reasm skb through instead of original frag skbs")
changed ipv6 defrag to not use the original skbs anymore.
So rather than keeping the original skbs around just to discard them
afterwards just use the original skbs directly for the fraglist of
the newly assembled skb and remove the extra clone/free operations.
The skb that completes the fragment queue is morphed into a the
reassembled one instead, just like ipv4 defrag.
openvswitch doesn't need any additional skb_morph magic anymore to deal
with this situation so just remove that.
A followup patch can then also remove the NF_HOOK (re)invocation in
the ipv6 netfilter defrag hook.
Cc: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_ct_frag6_gather() makes a clone of each skb passed to it, and if the
reassembly is successful, expects the caller to free all of the original
skbs using nf_ct_frag6_consume_orig(). This call was previously missing,
meaning that the original fragments were never freed (with the exception
of the last fragment to arrive).
Fix this by ensuring that all original fragments except for the last
fragment are freed via nf_ct_frag6_consume_orig(). The last fragment
will be morphed into the head, so it must not be freed yet. Furthermore,
retain the ->next pointer for the head after skb_morph().
Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If ip_defrag() returns an error other than -EINPROGRESS, then the skb is
freed. When handle_fragments() passes this back up to
do_execute_actions(), it will be freed again. Prevent this double free
by never freeing the skb in do_execute_actions() for errors returned by
ovs_ct_execute. Always free it in ovs_ct_execute() error paths instead.
Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
