Avoid using nested zero-sized arrays to allow compilation with MSVC.
Also, make sure the immediate data is accessed only if it exists, and
that the size is always calculated from struct learn_spec field
'n_bits'.
Fixes: dfe191d5fa ("ofp-actions: Waste less memory in learn actions.")
Reported-by: Alin Serdean <aserdean@cloudbasesolutions.com>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Change the value and mask to be added to the end of the set field
action without any extra bytes, exept for the usual ofp-actions
padding to 8 bytes. Together with some structure member packing this
saves on average about to 256 bytes for each set field and load action
(as set field internal representation is also used for load actions).
On a specific production data set each flow entry uses on average
about 4.2 load or set field actions. This means that with this patch
an average of more than 1kb can be saved for each flow with such a
flow table.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Make the immediate data member 'src_imm' of a learn spec allocated at
the end of the action for just the right size. This, together with
some structure packing saves on average of ~128 bytes for each learn
spec in each learn action. Typical learn actions have about 4 specs
each, so this amounts to saving about 0.5kb for each learn action.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Change mf_are_prereqs_ok() take a flow_wildcards pointer, so that the
wildcards can be set at the same time as the prerequisiteis are
checked. This makes it easier to write more obviously correct code.
Remove the functions mf_mask_field_and_prereqs() and
mf_mask_field_and_prereqs__(), and make the callers first check the
prerequisites, while supplying 'wc' to mf_are_prereqs_ok(), and if
successful, mask the bits of the field that were read or set using
mf_mask_field_masked().
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
To easily allow both in- and out-of-tree building of the Python
wrapper for the OVS JSON parser (e.g. w/ pip), move json.h to
include/openvswitch. This also requires moving lib/{hmap,shash}.h.
Both hmap.h and shash.h were #include-ing "util.h" even though the
headers themselves did not use anything from there, but rather from
include/openvswitch/util.h. Fixing that required including util.h
in several C files mostly due to OVS_NOT_REACHED and things like
xmalloc.
Signed-off-by: Terry Wilson <twilson@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
I don't know why this was here. The write_actions instruction works fine.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
Previously, the OF1.0 "enqueue" action was simply omitted when actions
were translated into OpenFlow 1.1 or later, which do not have a similar
action. This commit translates this action into an equivalent sequence
of actions.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
From time to time it confuses users that "group" actions disappear when
using OpenFlow 1.0.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
The patch adds a new action to support packet truncation. The new action
is formatted as 'output(port=n,max_len=m)', as output to port n, with
packet size being MIN(original_size, m).
One use case is to enable port mirroring to send smaller packets to the
destination port so that only useful packet information is mirrored/copied,
saving some performance overhead of copying entire packet payload. Example
use case is below as well as shown in the testcases:
- Output to port 1 with max_len 100 bytes.
- The output packet size on port 1 will be MIN(original_packet_size, 100).
# ovs-ofctl add-flow br0 'actions=output(port=1,max_len=100)'
- The scope of max_len is limited to output action itself. The following
packet size of output:1 and output:2 will be intact.
# ovs-ofctl add-flow br0 \
'actions=output(port=1,max_len=100),output:1,output:2'
- The Datapath actions shows:
# Datapath actions: trunc(100),1,1,2
Tested-at: https://travis-ci.org/williamtu/ovs-travis/builds/140037134
Signed-off-by: William Tu <u9012063@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Add support to export tunnel information for flow-based IPFIX.
The original steps to configure flow level IPFIX:
1) Create a new record in Flow_Sample_Collector_Set table:
'ovs-vsctl -- create Flow_Sample_Collector_Set id=1 bridge="Bridge UUID"'
2) Add IPFIX configuration which is referred by corresponding
row in Flow_Sample_Collector_Set table:
'ovs-vsctl -- set Flow_Sample_Collector_Set
"Flow_Sample_Collector_Set UUID" ipfix=@i -- --id=@i create IPFIX
targets=\"IP:4739\" obs_domain_id=123 obs_point_id=456
cache_active_timeout=60 cache_max_flows=13'
3) Add sample action to the flows:
'ovs-ofctl add-flow mybridge in_port=1,
actions=sample'('probability=65535,collector_set_id=1,
obs_domain_id=123,obs_point_id=456')',output:3'
NXAST_SAMPLE action was used in step 3. In order to support exporting tunnel
information, the NXAST_SAMPLE2 action was added and with NXAST_SAMPLE2 action
in this patch, the step 3 should be configured like below:
'ovs-ofctl add-flow mybridge in_port=1,
actions=sample'('probability=65535,collector_set_id=1,obs_domain_id=123,
obs_point_id=456,sampling_port=3')',output:3'
'sampling_port' can be equal to ingress port or one of egress ports. If sampling
port is equal to output port and the output port is a tunnel port,
OVS_USERSPACE_ATTR_EGRESS_TUN_PORT will be set in the datapath flow sample action.
When flow sample action upcall happens, tunnel information will be retrieved from
the datapath and then IPFIX can export egress tunnel port information. If
samping_port=65535 (OFPP_NONE), flow-based IPFIX will keep the same behavior
as before.
This patch mainly do three tasks:
1) Add a new flow sample action NXAST_SAMPLE2 to support exporting
tunnel information. NXAST_SAMPLE2 action has a new added field
'sampling_port'.
2) Use 'other_configure: enable-tunnel-sampling' to enable or disable
exporting tunnel information.
3) If 'sampling_port' is equal to output port and output port is a tunnel
port, the translation of OpenFlow "sample" action should first emit
set(tunnel(...)), then the sample action itself. It makes sure the
egress tunnel information can be sampled.
4) Add a test of flow-based IPFIX for tunnel set.
How to test flow-based IPFIX:
1) Setup a test environment with two Linux host with Docker supported
2) Create a Docker container and a GRE tunnel port on each host
3) Use ovs-docker to add the container on the bridge
4) Listen on port 4739 on the collector machine and use wireshark to filter
'cflow' packets.
5) Configure flow-based IPFIX:
- 'ovs-vsctl -- create Flow_Sample_Collector_Set id=1 bridge="Bridge UUID"'
- 'ovs-vsctl -- set Flow_Sample_Collector_Set
"Flow_Sample_Collector_Set UUID" ipfix=@i -- --id=@i create IPFIX \
targets=\"IP:4739\" cache_active_timeout=60 cache_max_flows=13 \
other_config:enable-tunnel-sampling=true'
- 'ovs-ofctl add-flow mybridge in_port=1,
actions=sample'('probability=65535,collector_set_id=1,obs_domain_id=123,
obs_point_id=456,sampling_port=3')',output:3'
Note: The in-port is container port. The output port and sampling_port
are both open flow port and the output port is a GRE tunnel port.
6) Ping from the container whose host enabled flow-based IPFIX.
7) Get the IPFIX template pakcets and IPFIX information packets.
Signed-off-by: Benli Ye <daniely@vmware.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
This fixes several tests that failed on big-endian systems because "union
flow_in_port" overlays an ofp_port_t and odp_port_t and in some cases it
is not easy to determine which one is in use.
This commit also fixes up a few places where this broke other code.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Aaron Conole <aconole@redhat.com>
Acked-by: Gerhard Stenzel <gstenzel@linux.vnet.ibm.com>
Conntrack action used in group buckets lets
us do simple load-balancing.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
[guru@ovn.org updated the commit message and made
a small change to the test output format]
Signed-off-by: Gurucharan Shetty <guru@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Add the missing NAT documentation to ovs-ofctl man page and add
validation of the NAT flags to NAT action decoding and parsing.
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Open vSwitch must ensure that flow translation takes a finite amount of
time. Until now it has implemented this by limiting the depth of
recursion. The initial limit, in version 1.0.1, was no recursion at all,
and then over the years it has increased to 8 levels, then 16, then 32,
and 64 for the last few years. Now reports are coming in that 64 levels
are inadequate for some OVN setups. The natural inclination would be to
double the limit again to 128 levels.
This commit attempts another approach. Instead of increasing the limit,
it reduces the class of resubmits that count against the limit. Since the
goal for the depth limit is to prevent an infinite amount of work, it's
not necessary to count resubmits that can't lead to infinite work. In
particular, a resubmit from a table numbered x to a table y > x cannot do
this, because any OpenFlow switch has a finite number of tables. Because
in fact a resubmit (or goto_table) from one table to a later table is the
most common form of an OpenFlow pipeline, I suspect that this will greatly
alleviate the pressure to increase the depth limit.
Reported-by: Guru Shetty <guru@ovn.org>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Ryan Moats <rmoats@us.ibm.com>
When decoding the 'note' action, variable-length data could be pushed to
a buffer immediately prior to calling ofpact_finish_NOTE(). The
ofpbuf_put() could cause reallocation, in which case the finish call
could access freed memory. Fix the issue by updating the local pointer
before passing it to ofpact_finish_NOTE().
If the memory was reused, it may trigger an assert in ofpact_finish():
assertion ofpact == ofpacts->header failed in ofpact_finish()
With the included test, make check-valgrind reports:
Invalid read of size 1
at 0x500A9F: ofpact_finish_NOTE (ofp-actions.h:988)
by 0x4FE5C1: decode_NXAST_RAW_NOTE (ofp-actions.c:4557)
by 0x4FBC05: ofpact_decode (ofp-actions.inc2:3831)
by 0x4F7E87: ofpacts_decode (ofp-actions.c:5780)
by 0x4F709F: ofpacts_pull_openflow_actions__ (ofp-actions.c:5817)
by 0x4F7856: ofpacts_pull_openflow_instructions (ofp-actions.c:6397)
by 0x52CFF5: ofputil_decode_flow_mod (ofp-util.c:1727)
by 0x5227A9: ofp_print_flow_mod (ofp-print.c:789)
by 0x520823: ofp_to_string__ (ofp-print.c:3235)
by 0x5204F6: ofp_to_string (ofp-print.c:3468)
by 0x5925C8: do_recv (vconn.c:644)
by 0x592372: vconn_recv (vconn.c:598)
by 0x565CEA: rconn_recv (rconn.c:703)
by 0x46CB62: ofconn_run (connmgr.c:1367)
by 0x46C7AD: connmgr_run (connmgr.c:320)
by 0x4224A9: ofproto_run (ofproto.c:1763)
by 0x407C0D: bridge_run__ (bridge.c:2888)
by 0x40767A: bridge_run (bridge.c:2943)
by 0x4161B7: main (ovs-vswitchd.c:120)
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Ansis Atteka <ansisatteka@gmail.com>
This commit also adds several #include directives in source files in
order to make the 'ofp-util.h' move possible
Signed-off-by: Ben Warren <ben@skyportsystems.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
This commit also moves some bitmap macros into public header files and
adds some #include directives in soure files in order to make the
'meta-flow.h' move possible.
Signed-off-by: Ben Warren <ben@skyportsystems.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
It's pretty easy to forget to update the pointer to an ofpact when
finishing it. This commit forces the caller to pass a pointer-to-pointer
instead, and uses that to automatically update the pointer. There still
could be cases that retain other pointers into the ofpbuf, but I imagine
that this is harder to misuse.
Suggested-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
ofpact_finish() may now reallocate the buffer it is passed, but not all
callers updated their local pointers to the current action in the
buffer. This could potentially lead to several use-after-free bugs.
Update ofpact_finish() to return the new pointer to the ofpact which is
provided, and update the calling points to ensure that their local
pointers are pointing into the correct (potentially reallocated) buffer.
Fixes: 2bd318dec2 ("ofp-actions: Make composing actions harder to screw up.")
Reported-by: William Tu <u9012063@gmail.com>
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Acked-by: Ryan Moats <rmoats@us.ibm.com>
Add color output for flow actions for ovs-ofctl dump-flows command
utility, by inserting color markers in the functions responsible for
printing those actions.
Signed-off-by: Quentin Monnet <quentin.monnet@6wind.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Variable-length actions must have a nonzero length; if they don't,
something went wrong and we should bail out.
Suggested-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
When decoding a variable-length action, if the length of the action
exceeds the length storable in a uint16_t then something has gone
terribly wrong. Assert that this is not the case.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
If the actions list in an incoming flow mod is long enough, and there is
a bundle() action with 3 or more slaves, then it is possible for a
reallocation to occur after placing the ofpact_bundle into the ofpacts
buffer, while slave ports into the buffer. If the memory freed by this
reallocation is then passed to another thread, then that thread may
modify the value that bundle->n_slaves points to. If this occurs quickly
enough before the main thread finishes copying all of the slaves, then
the iteration may continue beyond the originally intended number of
slaves, copying (and swapping) an undetermined number of 2-byte chunks
from the openflow message. Finally, the length of the ofpact will be
updated based on how much data was written to the buffer, which may be
significantly longer than intended.
In many cases, the freed memory may not be allocated to another thread
and be left untouched. In some milder bug cases, this will lead to
'bundle' actions using more memory than required. In more serious cases,
this length may then exceed the maximum length of an OpenFlow action,
which is then stored (truncated) into the 16-bit length field in the
ofpact header. Later execution of ofpacts_verify() would then use this
length to iterate through the ofpacts, and may dereference memory in
unintended ways, causing crashes or infinite loops by attempting to
parse/validate arbitrary data as ofpact objects.
Fix the issue by updating 'bundle' within the iteration, immediately
after (potentially) expanding the bundle.
Thanks to Jarno Rajahalme for his keen pair of eyes on finding this
issue.
VMWare-BZ: #1614715
Fixes: f25d0cf3c3 ("Introduce ofpacts, an abstraction of OpenFlow actions.")
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
One purpose of OpenFlow packet-in messages is to allow a controller to
interpose on the path of a packet through the flow tables. If, for
example, the controller needs to modify a packet in some way that the
switch doesn't directly support, the controller should be able to
program the switch to send it the packet, then modify the packet and
send it back to the switch to continue through the flow table.
That's the theory. In practice, this doesn't work with any but the
simplest flow tables. Packet-in messages simply don't include enough
context to allow the flow table traversal to continue. For example:
* Via "resubmit" actions, an Open vSwitch packet can have an
effective "call stack", but a packet-in can't describe it, and
so it would be lost.
* A packet-in can't preserve the stack used by NXAST_PUSH and
NXAST_POP actions.
* A packet-in can't preserve the OpenFlow 1.1+ action set.
* A packet-in can't preserve the state of Open vSwitch mirroring
or connection tracking.
This commit introduces a solution called "continuations". A continuation
is the state of a packet's traversal through OpenFlow flow tables. A
"controller" action with the "pause" flag, which is newly implemented in
this commit, generates a continuation and sends it to the OpenFlow
controller in a packet-in asynchronous message (only NXT_PACKET_IN2
supports continuations, so the controller must configure them with
NXT_SET_PACKET_IN_FORMAT). The controller processes the packet-in,
possibly modifying some of its data, and sends it back to the switch with
an NXT_RESUME request, which causes flow table traversal to continue. In
principle, a single packet can be paused and resumed multiple times.
Another way to look at it is:
- "pause" is an extension of the existing OFPAT_CONTROLLER
action. It sends the packet to the controller, with full
pipeline context (some of which is switch implementation
dependent, and may thus vary from switch to switch).
- A continuation is an extension of OFPT_PACKET_IN, allowing for
implementation dependent metadata.
- NXT_RESUME is an extension of OFPT_PACKET_OUT, with the
semantics that the pipeline processing is continued with the
original translation context from where it was left at the time
it was paused.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
A number of times I've looked at code and thought that it would be easier
to understand if I could write an initializer instead of
ofpbuf_use_const(). This commit adds a function for that purpose and
adapts a lot of code to use it, in the places where I thought it made
the code better.
In theory this could improve code generation since the new function can
be inlined whereas ofpbuf_use_const() isn't. But I guess that's probably
insignificant; the intent of this change is code readability.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
This makes it accept the same syntax as parse_NOTE(), so that that function
can be simplified. In an upcoming commit a second action will also be
able to take advantage of the same feature.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
An upcoming commit will have a need to parse actions incrementally, so this
change makes that easier to do.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>
It does more than just update the length now, so this is a more accurate
name.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Russell Bryant <russell@ovn.org>
Until now, composing a fixed-length action with ofpact_put_<NAME>() failed
to append any padding required after the action. This commit changes that
so that these calls now add padding. This meant that the function
ofpact_pad(), which was until now required in various unintuitive places,
is no longer required, and removes it.
Variable-length actions still require calling ofpact_update_len() after
composition. I don't see a way to avoid that.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Russell Bryant <russell@ovn.org>
ofpacts_pull_openflow_instructions() should fill 'ofpacts' with a list
of OpenFlow actions and each action (including the last one) should be
padded to OFP_ACTION_ALIGN(8) bytes.
In most of the cases this is taken care of (e.g. by ofpacts_decode), but
for the Goto-Table instruction (and Clear-Actions, based on a quick code
inspection), this wasn't the case.
This caused the copy operation in recirc_unroll_actions() to read two
extra bytes after an allocated area (not a big deal, but enough to
displease the AddressSanitizer).
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: Daniele Di Proietto <diproiettod@vmware.com>
Co-authored-by: Daniele Di Proietto <diproiettod@vmware.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
This function finds the mf destination field for any ofpact, returning
NULL if not applicable. It will be used by the next patch to properly
reject OpenFlow flows with conntrack actions when conntrack is
unsupported by the datapath.
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
The out_port and out_group matches only looked at apply_actions
instructions, but my interpretation of the OpenFlow spec is that they
should also look inside write_actions.
This affected the output of (and in one case the correctness of) some
tests, so this updates them.
Reported-by: Gavin Remaley <gavin_remaley@selinc.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Extend OVS conntrack interface to cover NAT. New nested NAT action
may be included with a CT action. A bare NAT action only mangles
existing connections. If a NAT action with src or dst range attribute
is included, new (non-committed) connections are mangled according to
the NAT attributes.
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: Ben Pfaff <blp@ovn.org>
Restrictions from embedded actions should be folded in rather than
discarded.
Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Joe Stringer <joestringer@nicira.com>
This patch adds support for specifying a "helper" or ALG to assist
connection tracking for protocols that consist of multiple streams.
Initially, only support for FTP is included.
Below is an example set of flows to allow FTP control connections from
port 1->2 to establish active data connections in the reverse direction:
table=0,priority=1,action=drop
table=0,arp,action=normal
table=0,in_port=1,tcp,action=ct(alg=ftp,commit),2
table=0,in_port=2,tcp,ct_state=-trk,action=ct(table=1)
table=1,in_port=2,tcp,ct_state=+trk+est,action=1
table=1,in_port=2,tcp,ct_state=+trk+rel,action=ct(commit),1
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
This patch adds a new 128-bit metadata field to the connection tracking
interface. When a label is specified as part of the ct action and the
connection is committed, the value is saved with the current connection.
Subsequent ct lookups with the table specified will expose this metadata
as the "ct_label" field in the flow.
For example, to allow new TCP connections from port 1->2 and only allow
established connections from port 2->1, and to associate a label with
those connections:
table=0,priority=1,action=drop
table=0,arp,action=normal
table=0,in_port=1,tcp,action=ct(commit,exec(set_field:1->ct_label)),2
table=0,in_port=2,ct_state=-trk,tcp,action=ct(table=1)
table=1,in_port=2,ct_state=+trk,ct_label=1,tcp,action=1
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
This patch adds a new 32-bit metadata field to the connection tracking
interface. When a mark is specified as part of the ct action and the
connection is committed, the value is saved with the current connection.
Subsequent ct lookups with the table specified will expose this metadata
as the "ct_mark" field in the flow.
For example, to allow new TCP connections from port 1->2 and only allow
established connections from port 2->1, and to associate a mark with those
connections:
table=0,priority=1,action=drop
table=0,arp,action=normal
table=0,in_port=1,tcp,action=ct(commit,exec(set_field:1->ct_mark)),2
table=0,in_port=2,ct_state=-trk,tcp,action=ct(table=1)
table=1,in_port=2,ct_state=+trk,ct_mark=1,tcp,action=1
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
This patch adds a new action and fields to OVS that allow connection
tracking to be performed. This support works in conjunction with the
Linux kernel support merged into the Linux-4.3 development cycle.
Packets have two possible states with respect to connection tracking:
Untracked packets have not previously passed through the connection
tracker, while tracked packets have previously been through the
connection tracker. For OpenFlow pipeline processing, untracked packets
can become tracked, and they will remain tracked until the end of the
pipeline. Tracked packets cannot become untracked.
Connections can be unknown, uncommitted, or committed. Packets which are
untracked have unknown connection state. To know the connection state,
the packet must become tracked. Uncommitted connections have no
connection state stored about them, so it is only possible for the
connection tracker to identify whether they are a new connection or
whether they are invalid. Committed connections have connection state
stored beyond the lifetime of the packet, which allows later packets in
the same connection to be identified as part of the same established
connection, or related to an existing connection - for instance ICMP
error responses.
The new 'ct' action transitions the packet from "untracked" to
"tracked" by sending this flow through the connection tracker.
The following parameters are supported initally:
- "commit": When commit is executed, the connection moves from
uncommitted state to committed state. This signals that information
about the connection should be stored beyond the lifetime of the
packet within the pipeline. This allows future packets in the same
connection to be recognized as part of the same "established" (est)
connection, as well as identifying packets in the reply (rpl)
direction, or packets related to an existing connection (rel).
- "zone=[u16|NXM]": Perform connection tracking in the zone specified.
Each zone is an independent connection tracking context. When the
"commit" parameter is used, the connection will only be committed in
the specified zone, and not in other zones. This is 0 by default.
- "table=NUMBER": Fork pipeline processing in two. The original instance
of the packet will continue processing the current actions list as an
untracked packet. An additional instance of the packet will be sent to
the connection tracker, which will be re-injected into the OpenFlow
pipeline to resume processing in the specified table, with the
ct_state and other ct match fields set. If the table is not specified,
then the packet is submitted to the connection tracker, but the
pipeline does not fork and the ct match fields are not populated. It
is strongly recommended to specify a table later than the current
table to prevent loops.
When the "table" option is used, the packet that continues processing in
the specified table will have the ct_state populated. The ct_state may
have any of the following flags set:
- Tracked (trk): Connection tracking has occurred.
- Reply (rpl): The flow is in the reply direction.
- Invalid (inv): The connection tracker couldn't identify the connection.
- New (new): This is the beginning of a new connection.
- Established (est): This is part of an already existing connection.
- Related (rel): This connection is related to an existing connection.
For more information, consult the ovs-ofctl(8) man pages.
Below is a simple example flow table to allow outbound TCP traffic from
port 1 and drop traffic from port 2 that was not initiated by port 1:
table=0,priority=1,action=drop
table=0,arp,action=normal
table=0,in_port=1,tcp,ct_state=-trk,action=ct(commit,zone=9),2
table=0,in_port=2,tcp,ct_state=-trk,action=ct(zone=9,table=1)
table=1,in_port=2,ct_state=+trk+est,tcp,action=1
table=1,in_port=2,ct_state=+trk+new,tcp,action=drop
Based on original design by Justin Pettit, contributions from Thomas
Graf and Daniele Di Proietto.
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
A future patch will make use of this version parameter to pass nested
attributes. Prepare for that by adding the parameter as an unused
variable for the existing functions.
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>