Commit Graph

649 Commits

Author SHA1 Message Date
Pablo Neira Ayuso f6b3ef5e38 Merge tag 'ipvs-for-v4.10' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-next
Simon Horman says:

====================
IPVS Updates for v4.10

please consider these enhancements to the IPVS for v4.10.

* Decrement the IP ttl in all the modes in order to prevent infinite
  route loops. Thanks to Dwip Banerjee.
* Use IS_ERR_OR_NULL macro. Clean-up from Gao Feng.
====================

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-12-04 20:46:16 +01:00
Alexey Dobriyan c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
David S. Miller bb598c1b8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 10:54:36 -05:00
Dwip Banerjee 8d8e20e2d7 ipvs: Decrement ttl
We decrement the IP ttl in all the modes in order to prevent infinite
route loops. The changes were done based on Julian Anastasov's
suggestions in a prior thread.

The ttl based check/discard and the actual decrement are done in
__ip_vs_get_out_rt() and in __ip_vs_get_out_rt_v6(), for the IPv6
case. decrement_ttl() implements the actual functionality for the
two cases.

Signed-off-by: Dwip Banerjee <dwip@linux.vnet.ibm.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-11-15 09:49:20 +01:00
Gao Feng fe24a0c3a9 ipvs: Use IS_ERR_OR_NULL(svc) instead of IS_ERR(svc) || svc == NULL
This minor refactoring does not change the logic of function
ip_vs_genl_dump_dests.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-11-15 09:49:19 +01:00
WANG Cong 8fbfef7f50 ipvs: use IPVS_CMD_ATTR_MAX for family.maxattr
family.maxattr is the max index for policy[], the size of
ops[] is determined with ARRAY_SIZE().

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-08 23:53:30 +01:00
Arnd Bergmann 5747620257 netfilter: ip_vs_sync: fix bogus maybe-uninitialized warning
Building the ip_vs_sync code with CONFIG_OPTIMIZE_INLINING on x86
confuses the compiler to the point where it produces a rather
dubious warning message:

net/netfilter/ipvs/ip_vs_sync.c:1073:33: error: ‘opt.init_seq’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  struct ip_vs_sync_conn_options opt;
                                 ^~~
net/netfilter/ipvs/ip_vs_sync.c:1073:33: error: ‘opt.delta’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
net/netfilter/ipvs/ip_vs_sync.c:1073:33: error: ‘opt.previous_delta’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
net/netfilter/ipvs/ip_vs_sync.c:1073:33: error: ‘*((void *)&opt+12).init_seq’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
net/netfilter/ipvs/ip_vs_sync.c:1073:33: error: ‘*((void *)&opt+12).delta’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
net/netfilter/ipvs/ip_vs_sync.c:1073:33: error: ‘*((void *)&opt+12).previous_delta’ may be used uninitialized in this function [-Werror=maybe-uninitialized]

The problem appears to be a combination of a number of factors, including
the __builtin_bswap32 compiler builtin being slightly odd, having a large
amount of code inlined into a single function, and the way that some
functions only get partially inlined here.

I've spent way too much time trying to work out a way to improve the
code, but the best I've come up with is to add an explicit memset
right before the ip_vs_seq structure is first initialized here. When
the compiler works correctly, this has absolutely no effect, but in the
case that produces the warning, the warning disappears.

In the process of analysing this warning, I also noticed that
we use memcpy to copy the larger ip_vs_sync_conn_options structure
over two members of the ip_vs_conn structure. This works because
the layout is identical, but seems error-prone, so I'm changing
this in the process to directly copy the two members. This change
seemed to have no effect on the object code or the warning, but
it deals with the same data, so I kept the two changes together.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-10-28 14:14:51 +02:00
Johannes Berg 56989f6d85 genetlink: mark families as __ro_after_init
Now genl_register_family() is the only thing (other than the
users themselves, perhaps, but I didn't find any doing that)
writing to the family struct.

In all families that I found, genl_register_family() is only
called from __init functions (some indirectly, in which case
I've add __init annotations to clarifly things), so all can
actually be marked __ro_after_init.

This protects the data structure from accidental corruption.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:09 -04:00
Johannes Berg 489111e5c2 genetlink: statically initialize families
Instead of providing macros/inline functions to initialize
the families, make all users initialize them statically and
get rid of the macros.

This reduces the kernel code size by about 1.6k on x86-64
(with allyesconfig).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:09 -04:00
Johannes Berg a07ea4d994 genetlink: no longer support using static family IDs
Static family IDs have never really been used, the only
use case was the workaround I introduced for those users
that assumed their family ID was also their multicast
group ID.

Additionally, because static family IDs would never be
reserved by the generic netlink code, using a relatively
low ID would only work for built-in families that can be
registered immediately after generic netlink is started,
which is basically only the control family (apart from
the workaround code, which I also had to add code for so
it would reserve those IDs)

Thus, anything other than GENL_ID_GENERATE is flawed and
luckily not used except in the cases I mentioned. Move
those workarounds into a few lines of code, and then get
rid of GENL_ID_GENERATE entirely, making it more robust.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:16:09 -04:00
Florian Westphal a6c46d9bc9 ipvs: use nf_ct_kill helper
Once timer is removed from nf_conn struct we cannot open-code
the removal sequence anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-12 00:43:52 +02:00
David S. Miller c42d7121fb Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for net-next,
they are:

1) Count pre-established connections as active in "least connection"
   schedulers such that pre-established connections to avoid overloading
   backend servers on peak demands, from Michal Kubecek via Simon Horman.

2) Address a race condition when resizing the conntrack table by caching
   the bucket size when fulling iterating over the hashtable in these
   three possible scenarios: 1) dump via /proc/net/nf_conntrack,
   2) unlinking userspace helper and 3) unlinking custom conntrack timeout.
   From Liping Zhang.

3) Revisit early_drop() path to perform lockless traversal on conntrack
   eviction under stress, use del_timer() as synchronization point to
   avoid two CPUs evicting the same entry, from Florian Westphal.

4) Move NAT hlist_head to nf_conn object, this simplifies the existing
   NAT extension and it doesn't increase size since recent patches to
   align nf_conn, from Florian.

5) Use rhashtable for the by-source NAT hashtable, also from Florian.

6) Don't allow --physdev-is-out from OUTPUT chain, just like
   --physdev-out is not either, from Hangbin Liu.

7) Automagically set on nf_conntrack counters if the user tries to
   match ct bytes/packets from nftables, from Liping Zhang.

8) Remove possible_net_t fields in nf_tables set objects since we just
   simply pass the net pointer to the backend set type implementations.

9) Fix possible off-by-one in h323, from Toby DiPasquale.

10) early_drop() may be called from ctnetlink patch, so we must hold
    rcu read size lock from them too, this amends Florian's patch #3
    coming in this batch, from Liping Zhang.

11) Use binary search to validate jump offset in x_tables, this
    addresses the O(n!) validation that was introduced recently
    resolve security issues with unpriviledge namespaces, from Florian.

12) Fix reference leak to connlabel in error path of nft_ct, from Zhang.

13) Three updates for nft_log: Fix log prefix leak in error path. Bail
    out on loglevel larger than debug in nft_log and set on the new
    NF_LOG_F_COPY_LEN flag when snaplen is specified. Again from Zhang.

14) Allow to filter rule dumps in nf_tables based on table and chain
    names.

15) Simplify connlabel to always use 128 bits to store labels and
    get rid of unused function in xt_connlabel, from Florian.

16) Replace set_expect_timeout() by mod_timer() from the h323 conntrack
    helper, by Gao Feng.

17) Put back x_tables module reference in nft_compat on error, from
    Liping Zhang.

18) Add a reference count to the x_tables extensions cache in
    nft_compat, so we can remove them when unused and avoid a crash
    if the extensions are rmmod, again from Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-24 22:02:36 -07:00
Pablo Neira Ayuso c080b460df Merge tag 'ipvs-for-v4.8' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-next
Simon Horman says:

====================
IPVS Updates for v4.8

please consider these enhancements to the IPVS. This alters the behaviour
of the "least connection" schedulers such that pre-established connections
are included in the active connection count. This avoids overloading
servers when a large number of new connections arrive in a short space of
time - e.g. when clients reconnect after a node or network failure.
====================

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-11 12:16:34 +02:00
Michal Kubecek be2cef4990 ipvs: count pre-established TCP states as active
Some users observed that "least connection" distribution algorithm doesn't
handle well bursts of TCP connections from reconnecting clients after
a node or network failure.

This is because the algorithm counts active connection as worth 256
inactive ones where for TCP, "active" only means TCP connections in
ESTABLISHED state. In case of a connection burst, new connections are
handled before previous ones have finished the three way handshaking so
that all are still counted as "inactive", i.e. cheap ones. The become
"active" quickly but at that time, all of them are already assigned to one
real server (or few), resulting in highly unbalanced distribution.

Address this by counting the "pre-established" states as "active".

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-07-07 20:30:52 +02:00
Quentin Armitage 3777ed688f ipvs: fix bind to link-local mcast IPv6 address in backup
When using HEAD from
https://git.kernel.org/cgit/utils/kernel/ipvsadm/ipvsadm.git/,
the command:
ipvsadm --start-daemon backup --mcast-interface eth0.60 \
    --mcast-group ff02::1:81
fails with the error message:
Argument list too long

whereas both:
ipvsadm --start-daemon master --mcast-interface eth0.60 \
    --mcast-group ff02::1:81
and:
ipvsadm --start-daemon backup --mcast-interface eth0.60 \
    --mcast-group 224.0.0.81
are successful.

The error message "Argument list too long" isn't helpful. The error occurs
because an IPv6 address is given in backup mode.

The error is in make_receive_sock() in net/netfilter/ipvs/ip_vs_sync.c,
since it fails to set the interface on the address or the socket before
calling inet6_bind() (via sock->ops->bind), where the test
'if (!sk->sk_bound_dev_if)' failed.

Setting sock->sk->sk_bound_dev_if on the socket before calling
inet6_bind() resolves the issue.

Fixes: d33288172e ("ipvs: add more mcast parameters for the sync daemon")
Signed-off-by: Quentin Armitage <quentin@armitage.org.uk>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-07-07 20:21:32 +02:00
Marco Angaroni 3ec10d3a2b ipvs: update real-server binding of outgoing connections in SIP-pe
Previous patch that introduced handling of outgoing packets in SIP
persistent-engine did not call ip_vs_check_template() in case packet was
matching a connection template. Assumption was that real-server was
healthy, since it was sending a packet just in that moment.

There are however real-server fault conditions requiring that association
between call-id and real-server (represented by connection template)
gets updated. Here is an example of the sequence of events:
  1) RS1 is a back2back user agent that handled call-id1 and call-id2
  2) RS1 is down and was marked as unavailable
  3) new message from outside comes to IPVS with call-id1
  4) IPVS reschedules the message to RS2, which becomes new call handler
  5) RS2 forwards the message outside, translating call-id1 to call-id2
  6) inside pe->conn_out() IPVS matches call-id2 with existing template
  7) IPVS does not change association call-id2 <-> RS1
  8) new message comes from client with call-id2
  9) IPVS reschedules the message to a real-server potentially different
     from RS2, which is now the correct destination

This patch introduces ip_vs_check_template() call in the handling of
outgoing packets for SIP-pe. And also introduces a second optional
argument for ip_vs_check_template() that allows to check if dest
associated to a connection template is the same dest that was identified
as the source of the packet. This is to change the real-server bound to a
particular call-id independently from its availability status: the idea
is that it's more reliable, for in->out direction (where internal
network can be considered trusted), to always associate a call-id with
the last real-server that used it in one of its messages. Think about
above sequence of events where, just after step 5, RS1 returns instead
to be available.

Comparison of dests is done by simply comparing pointers to struct
ip_vs_dest; there should be no cases where struct ip_vs_dest keeps its
memory address, but represent a different real-server in terms of
ip-address / port.

Fixes: 39b9722315 ("ipvs: handle connections started by real-servers")
Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-06-06 09:47:25 +09:00
Tom Herbert 7e13318daa net: define gso types for IPx over IPv4 and IPv6
This patch defines two new GSO definitions SKB_GSO_IPXIP4 and
SKB_GSO_IPXIP6 along with corresponding NETIF_F_GSO_IPXIP4 and
NETIF_F_GSO_IPXIP6. These are used to described IP in IP
tunnel and what the outer protocol is. The inner protocol
can be deduced from other GSO types (e.g. SKB_GSO_TCPV4 and
SKB_GSO_TCPV6). The GSO types of SKB_GSO_IPIP and SKB_GSO_SIT
are removed (these are both instances of SKB_GSO_IPXIP4).
SKB_GSO_IPXIP6 will be used when support for GSO with IP
encapsulation over IPv6 is added.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20 18:03:15 -04:00
David S. Miller e8ed77dfa9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following large patchset contains Netfilter updates for your
net-next tree. My initial intention was to send you this in two goes but
when I looked back twice I already had this burden on top of me.

Several updates for IPVS from Marco Angaroni:

1) Allow SIP connections originating from real-servers to be load
   balanced by the SIP persistence engine as is already implemented
   in the other direction.

2) Release connections immediately for One-packet-scheduling (OPS)
   in IPVS, instead of making it via timer and rcu callback.

3) Skip deleting conntracks for each one packet in OPS, and don't call
   nf_conntrack_alter_reply() since no reply is expected.

4) Enable drop on exhaustion for OPS + SIP persistence.

Miscelaneous conntrack updates from Florian Westphal, including fix for
hash resize:

5) Move conntrack generation counter out of conntrack pernet structure
   since this is only used by the init_ns to allow hash resizing.

6) Use get_random_once() from packet path to collect hash random seed
    instead of our compound.

7) Don't disable BH from ____nf_conntrack_find() for statistics,
   use NF_CT_STAT_INC_ATOMIC() instead.

8) Fix lookup race during conntrack hash resizing.

9) Introduce clash resolution on conntrack insertion for connectionless
   protocol.

Then, Florian's netns rework to get rid of per-netns conntrack table,
thus we use one single table for them all. There was consensus on this
change during the NFWS 2015 and, on top of that, it has recently been
pointed as a source of multiple problems from unpriviledged netns:

11) Use a single conntrack hashtable for all namespaces. Include netns
    in object comparisons and make it part of the hash calculation.
    Adapt early_drop() to consider netns.

12) Use single expectation and NAT hashtable for all namespaces.

13) Use a single slab cache for all namespaces for conntrack objects.

14) Skip full table scanning from nf_ct_iterate_cleanup() if the pernet
    conntrack counter tells us the table is empty (ie. equals zero).

Fixes for nf_tables interval set element handling, support to set
conntrack connlabels and allow set names up to 32 bytes.

15) Parse element flags from element deletion path and pass it up to the
    backend set implementation.

16) Allow adjacent intervals in the rbtree set type for dynamic interval
    updates.

17) Add support to set connlabel from nf_tables, from Florian Westphal.

18) Allow set names up to 32 bytes in nf_tables.

Several x_tables fixes and updates:

19) Fix incorrect use of IS_ERR_VALUE() in x_tables, original patch
    from Andrzej Hajda.

And finally, miscelaneous netfilter updates such as:

20) Disable automatic helper assignment by default. Note this proc knob
    was introduced by a900689264 ("netfilter: nf_ct_helper: allow to
    disable automatic helper assignment") 4 years ago to start moving
    towards explicit conntrack helper configuration via iptables CT
    target.

21) Get rid of obsolete and inconsistent debugging instrumentation
    in x_tables.

22) Remove unnecessary check for null after ip6_route_output().
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-09 15:02:58 -04:00
Marco Angaroni 698e2a8dca ipvs: make drop_entry protection effective for SIP-pe
DoS protection policy that deletes connections to avoid out of memory is
currently not effective for SIP-pe plus OPS-mode for two reasons:
  1) connection templates (holding SIP call-id) are always skipped in
     ip_vs_random_dropentry()
  2) in_pkts counter (used by drop_entry algorithm) is not incremented
     for connection templates

This patch addresses such problems with the following changes:
  a) connection templates associated (via their dest) to virtual-services
     configured in OPS mode are included in ip_vs_random_dropentry()
     monitoring. This applies to SIP-pe over UDP (which requires OPS mode),
     but is more general principle: when OPS is controlled by templates
     memory can be used only by templates themselves, since OPS conns are
     deleted after packet is forwarded.
  b) OPS connections, if controlled by a template, cause increment of
     in_pkts counter of their template. This is already happening but only
     in case director is in master-slave mode (see ip_vs_sync_conn()).

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-05-06 16:26:23 +09:00
Nicolas Dichtel cbdeafd7e1 netfilter/ipvs: use nla_put_u64_64bit()
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-25 15:09:11 -04:00
Pablo Neira Ayuso 6cd54fc60c Merge tag 'ipvs-for-v4.7' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-next
Simon Horman says:

====================
IPVS Updates for v4.7

please consider these enhancements to the IPVS. They allow SIP connections
originating from real-servers to be load balanced by the SIP psersitence
engine as is already implemented in the other direction. And for better one
packet scheduling (OPS) performance.
====================

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-25 15:35:53 +02:00
Marco Angaroni 8fb04d9fc7 ipvs: don't alter conntrack in OPS mode
When using OPS mode in conjunction with SIP persistent-engine, packets
originating from the same ip-address/port could be balanced to different
real servers, and (to properly handle SIP responses) OPS connections
are created in the in-out direction too, where ip_vs_update_conntrack()
is called to modify the reply tuple.

As a result, there can be collision of conntrack tuples, causing random
packet drops, as explained below:

conntrack1: orig=CIP->VIP, reply=RIP1->CIP
conntrack2: orig=RIP2->CIP, reply=CIP->VIP

Tuple CIP->VIP is both in orig of conntrack1 and reply of conntrack2.
The collision triggers packet drop inside nf_conntrack processing.

In addition, the current implementation deletes the conntrack object at
every expire of an OPS connection (once every forwarded packet), to have
it recreated from scratch at next packet traversing IPVS.

Since in OPS mode, by definition, we don't expect any associated
response, the choices implemented in this patch are:
a) don't call nf_conntrack_alter_reply() for OPS connections inside
   ip_vs_update_conntrack().
b) don't delete the conntrack object at OPS connection expire.

The result is that created conntrack objects for each tuple CIP->VIP,
RIP-N->CIP, etc. are left in UNREPLIED state and not modified by IPVS
OPS connection management. This eliminates packet drops and leaves
a single conntrack object for each tuple packets are sent from.

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-20 12:34:17 +10:00
Marco Angaroni 013b042465 ipvs: optimize release of connections in OPS mode
One-packet-scheduling is the most expensive mode in IPVS from
performance point of view: for each packet to be processed a new
connection data structure is created and, after packet is sent,
deleted by starting a new timer set to expire immediately.

SIP persistent-engine needs OPS mode to have Call-ID based load
balancing, so OPS mode performance has negative impact in SIP
protocol load balancing.

This patch aims to improve performance of OPS mode by means of the
following changes in the release mechanism of OPS connections:
a) call expire callback ip_vs_conn_expire() directly instead of
   starting a timer programmed to fire immediately.
b) avoid call_rcu() overhead inside expire callback, since OPS
   connection are not inserted in the hash-table and last just the
   time to process the packet, hence there is no concurrent access
   to such data structures.

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-20 12:34:17 +10:00
Marco Angaroni 39b9722315 ipvs: handle connections started by real-servers
When using LVS-NAT and SIP persistence-egine over UDP, the following
limitations are present with current implementation:

  1) To actually have load-balancing based on Call-ID header, you need to
     use one-packet-scheduling mode. But with one-packet-scheduling the
     connection is deleted just after packet is forwarded, so SIP responses
     coming from real-servers do not match any connection and SNAT is
     not applied.

  2) If you do not use "-o" option, IPVS behaves as normal UDP load
     balancer, so different SIP calls (each one identified by a different
     Call-ID) coming from the same ip-address/port go to the same
     real-server. So basically you don’t have load-balancing based on
     Call-ID as intended.

  3) Call-ID is not learned when a new SIP call is started by a real-server
     (inside-to-outside direction), but only in the outside-to-inside
     direction. This would be a general problem for all SIP servers acting
     as Back2BackUserAgent.

This patch aims to solve problems 1) and 3) while keeping OPS mode
mandatory for SIP-UDP, so that 2) is not a problem anymore.

The basic mechanism implemented is to make packets, that do not match any
existent connection but come from real-servers, create new connections
instead of let them pass without any effect.
When such packets pass through ip_vs_out(), if their source ip address and
source port match a configured real-server, a new connection is
automatically created in the same way as it would have happened if the
packet had come from outside-to-inside direction. A new connection template
is created too if the virtual-service is persistent and there is no
matching connection template found. The new connection automatically
created, if the service had "-o" option, is an OPS connection that lasts
only the time to forward the packet, just like it happens on the
ingress side.

The main part of this mechanism is implemented inside a persistent-engine
specific callback (at the moment only SIP persistent engine exists) and
is triggered only for UDP packets, since connection oriented protocols, by
using different set of ports (typically ephemeral ports) to open new
outgoing connections, should not need this feature.

The following requisites are needed for automatic connection creation; if
any is missing the packet simply goes the same way as before.
a) virtual-service is not fwmark based (this is because fwmark services
   do not store address and port of the virtual-service, required to
   build the connection data).
b) virtual-service and real-servers must not have been configured with
   omitted port (this is again to have all data to create the connection).

Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-04-20 12:34:17 +10:00
Alexander Duyck aed069df09 ip_tunnel_core: iptunnel_handle_offloads returns int and doesn't free skb
This patch updates the IP tunnel core function iptunnel_handle_offloads so
that we return an int and do not free the skb inside the function.  This
actually allows us to clean up several paths in several tunnels so that we
can free the skb at one point in the path without having to have a
secondary path if we are supporting tunnel offloads.

In addition it should resolve some double-free issues I have found in the
tunnels paths as I believe it is possible for us to end up triggering such
an event in the case of fou or gue.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-16 19:09:13 -04:00