summaryrefslogtreecommitdiff
path: root/include/uapi/linux/openvswitch.h
AgeCommit message (Collapse)Author
2015-10-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/ipv6/xfrm6_output.c net/openvswitch/flow_netlink.c net/openvswitch/vport-gre.c net/openvswitch/vport-vxlan.c net/openvswitch/vport.c net/openvswitch/vport.h The openvswitch conflicts were overlapping changes. One was the egress tunnel info fix in 'net' and the other was the vport ->send() op simplification in 'net-next'. The xfrm6_output.c conflicts was also a simplification overlapping a bug fix. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-21openvswitch: Clarify conntrack COMMIT behaviourJoe Stringer
The presence of this attribute does not modify the ct_state for the current packet, only future packets. Make this more clear in the header definition. Signed-off-by: Joe Stringer <joestringer@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/usb/asix_common.c net/ipv4/inet_connection_sock.c net/switchdev/switchdev.c In the inet_connection_sock.c case the request socket hashing scheme is completely different in net-next. The other two conflicts were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-07openvswitch: Change CT_ATTR_FLAGS to CT_ATTR_COMMITJoe Stringer
Previously, the CT_ATTR_FLAGS attribute, when nested under the OVS_ACTION_ATTR_CT, encoded a 32-bit bitmask of flags that modify the semantics of the ct action. It's more extensible to just represent each flag as a nested attribute, and this requires no additional error checking to reject flags that aren't currently supported. Suggested-by: Ben Pfaff <blp@nicira.com> 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>
2015-10-07openvswitch: Extend ct_state match field to 32 bitsJoe Stringer
The ct_state field was initially added as an 8-bit field, however six of the bits are already being used and use cases are already starting to appear that may push the limits of this field. This patch extends the field to 32 bits while retaining the internal representation of 8 bits. This should cover forward compatibility of the ABI for the foreseeable future. This patch also reorders the OVS_CS_F_* bits to be sequential. Suggested-by: Jarno Rajahalme <jrajahalme@nicira.com> 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>
2015-10-07openvswitch: Fix typos in CT headersJoe Stringer
These comments hadn't caught up to their implementations, fix them. Fixes: 7f8a436eaa2c "openvswitch: Add conntrack action" 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>
2015-10-07openvswitch: netlink attributes for IPv6 tunnelingJiri Benc
Add netlink attributes for IPv6 tunnel addresses. This enables IPv6 support for tunnels. Signed-off-by: Jiri Benc <jbenc@redhat.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05openvswitch: Rename LABEL->LABELSJoe Stringer
Conntrack LABELS (plural) are exposed by conntrack; rename the OVS name for these to be consistent with conntrack. Fixes: c2ac667 "openvswitch: Allow matching on conntrack label" 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>
2015-08-27openvswitch: Allow attaching helpers to ct actionJoe Stringer
Add support for using conntrack helpers to assist protocol detection. The new OVS_CT_ATTR_HELPER attribute of the CT action specifies a helper to be used for this connection. If no helper is specified, then helpers will be automatically applied as per the sysctl configuration of net.netfilter.nf_conntrack_helper. The helper may be specified as part of the conntrack action, eg: ct(helper=ftp). Initial packets for related connections should be committed to allow later packets for the flow to be considered established. Example ovs-ofctl flows allowing FTP connections from ports 1->2: in_port=1,tcp,action=ct(helper=ftp,commit),2 in_port=2,tcp,ct_state=-trk,action=ct(recirc) in_port=2,tcp,ct_state=+trk-new+est,action=1 in_port=2,tcp,ct_state=+trk+rel,action=1 Signed-off-by: Joe Stringer <joestringer@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27openvswitch: Allow matching on conntrack labelJoe Stringer
Allow matching and setting the ct_label field. As with ct_mark, this is populated by executing the CT action. The label field may be modified by specifying a label and mask nested under the CT action. It is stored as metadata attached to the connection. Label modification occurs after lookup, and will only persist when the conntrack entry is committed by providing the COMMIT flag to the CT action. Labels are currently fixed to 128 bits in size. Signed-off-by: Joe Stringer <joestringer@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27openvswitch: Allow matching on conntrack markJoe Stringer
Allow matching and setting the ct_mark field. As with ct_state and ct_zone, these fields are populated when the CT action is executed. To write to this field, a value and mask can be specified as a nested attribute under the CT action. This data is stored with the conntrack entry, and is executed after the lookup occurs for the CT action. The conntrack entry itself must be committed using the COMMIT flag in the CT action flags for this change to persist. Signed-off-by: Justin Pettit <jpettit@nicira.com> Signed-off-by: Joe Stringer <joestringer@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27openvswitch: Add conntrack actionJoe Stringer
Expose the kernel connection tracker via OVS. Userspace components can make use of the CT action to populate the connection state (ct_state) field for a flow. This state can be subsequently matched. Exposed connection states are OVS_CS_F_*: - NEW (0x01) - Beginning of a new connection. - ESTABLISHED (0x02) - Part of an existing connection. - RELATED (0x04) - Related to an established connection. - INVALID (0x20) - Could not track the connection for this packet. - REPLY_DIR (0x40) - This packet is in the reply direction for the flow. - TRACKED (0x80) - This packet has been sent through conntrack. When the CT action is executed by itself, it will send the packet through the connection tracker and populate the ct_state field with one or more of the connection state flags above. The CT action will always set the TRACKED bit. When the COMMIT flag is passed to the conntrack action, this specifies that information about the connection should be stored. This allows subsequent packets for the same (or related) connections to be correlated with this connection. Sending subsequent packets for the connection through conntrack allows the connection tracker to consider the packets as ESTABLISHED, RELATED, and/or REPLY_DIR. The CT action may optionally take a zone to track the flow within. This allows connections with the same 5-tuple to be kept logically separate from connections in other zones. If the zone is specified, then the "ct_zone" match field will be subsequently populated with the zone id. IP fragments are handled by transparently assembling them as part of the CT action. The maximum received unit (MRU) size is tracked so that refragmentation can occur during output. IP frag handling contributed by Andy Zhou. Based on original design by Justin Pettit. Signed-off-by: Joe Stringer <joestringer@nicira.com> Signed-off-by: Justin Pettit <jpettit@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Acked-by: Thomas Graf <tgraf@suug.ch> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21ip_tunnel: Make ovs_tunnel_info and ovs_key_ipv4_tunnel genericThomas Graf
Rename the tunnel metadata data structures currently internal to OVS and make them generic for use by all IP tunnels. Both structures are kernel internal and will stay that way. Their members are exposed to user space through individual Netlink attributes by OVS. It will therefore be possible to extend/modify these structures without affecting user ABI. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-01openvswitch: include datapath actions with sampled-packet upcall to userspaceNeil McKee
If new optional attribute OVS_USERSPACE_ATTR_ACTIONS is added to an OVS_ACTION_ATTR_USERSPACE action, then include the datapath actions in the upcall. This Directly associates the sampled packet with the path it takes through the virtual switch. Path information currently includes mangling, encapsulation and decapsulation actions for tunneling protocols GRE, VXLAN, Geneve, MPLS and QinQ, but this extension requires no further changes to accommodate datapath actions that may be added in the future. Adding path information enhances visibility into complex virtual networks. Signed-off-by: Neil McKee <neil.mckee@inmon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-07net: openvswitch: Support masked set actions.Jarno Rajahalme
OVS userspace already probes the openvswitch kernel module for OVS_ACTION_ATTR_SET_MASKED support. This patch adds the kernel module implementation of masked set actions. The existing set action sets many fields at once. When only a subset of the IP header fields, for example, should be modified, all the IP fields need to be exact matched so that the other field values can be copied to the set action. A masked set action allows modification of an arbitrary subset of the supported header bits without requiring the rest to be matched. Masked set action is now supported for all writeable key types, except for the tunnel key. The set tunnel action is an exception as any input tunnel info is cleared before action processing starts, so there is no tunnel info to mask. The kernel module converts all (non-tunnel) set actions to masked set actions. This makes action processing more uniform, and results in less branching and duplicating the action processing code. When returning actions to userspace, the fully masked set actions are converted back to normal set actions. We use a kernel internal action code to be able to tell the userspace provided and converted masked set actions apart. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-26openvswitch: Add support for unique flow IDs.Joe Stringer
Previously, flows were manipulated by userspace specifying a full, unmasked flow key. This adds significant burden onto flow serialization/deserialization, particularly when dumping flows. This patch adds an alternative way to refer to flows using a variable-length "unique flow identifier" (UFID). At flow setup time, userspace may specify a UFID for a flow, which is stored with the flow and inserted into a separate table for lookup, in addition to the standard flow table. Flows created using a UFID must be fetched or deleted using the UFID. All flow dump operations may now be made more terse with OVS_UFID_F_* flags. For example, the OVS_UFID_F_OMIT_KEY flag allows responses to omit the flow key from a datapath operation if the flow has a corresponding UFID. This significantly reduces the time spent assembling and transacting netlink messages. With all OVS_UFID_F_OMIT_* flags enabled, the datapath only returns the UFID and statistics for each flow during flow dump, increasing ovs-vswitchd revalidator performance by 40% or more. 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>
2015-01-15openvswitch: Support VXLAN Group Policy extensionThomas Graf
Introduces support for the group policy extension to the VXLAN virtual port. The extension is disabled by default and only enabled if the user has provided the respective configuration. ovs-vsctl add-port br0 vxlan0 -- \ set Interface vxlan0 type=vxlan options:exts=gbp The configuration interface to enable the extension is based on a new attribute OVS_VXLAN_EXT_GBP nested inside OVS_TUNNEL_ATTR_EXTENSION which can carry additional extensions as needed in the future. The group policy metadata is stored as binary blob (struct ovs_vxlan_opts) internally just like Geneve options but transported as nested Netlink attributes to user space. Renames the existing TUNNEL_OPTIONS_PRESENT to TUNNEL_GENEVE_OPT with the binary value kept intact, a new flag TUNNEL_VXLAN_OPT is introduced. The attributes OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS and existing OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS are implemented mutually exclusive. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-14openvswitch: packet messages need their own probe attribtueThomas Graf
User space is currently sending a OVS_FLOW_ATTR_PROBE for both flow and packet messages. This leads to an out-of-bounds access in ovs_packet_cmd_execute() because OVS_FLOW_ATTR_PROBE > OVS_PACKET_ATTR_MAX. Introduce a new OVS_PACKET_ATTR_PROBE with the same numeric value as OVS_FLOW_ATTR_PROBE to grow the range of accepted packet attributes while maintaining to be binary compatible with existing OVS binaries. Fixes: 05da589 ("openvswitch: Add support for OVS_FLOW_ATTR_PROBE.") Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Tracked-down-by: Florian Westphal <fw@strlen.de> Signed-off-by: Thomas Graf <tgraf@suug.ch> Reviewed-by: Jesse Gross <jesse@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-09openvswitch: Add support for OVS_FLOW_ATTR_PROBE.Jarno Rajahalme
This new flag is useful for suppressing error logging while probing for datapath features using flow commands. For backwards compatibility reasons the commands are executed normally, but error logging is suppressed. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-11-09openvswitch: Extend packet attribute for egress tunnel infoWenyu Zhang
OVS vswitch has extended IPFIX exporter to export tunnel headers to improve network visibility. To export this information userspace needs to know egress tunnel for given packet. By extending packet attributes datapath can export egress tunnel info for given packet. So that userspace can ask for egress tunnel info in userspace action. This information is used to build IPFIX data for given flow. Signed-off-by: Wenyu Zhang <wenyuz@vmware.com> Acked-by: Romain Lenglet <rlenglet@vmware.com> Acked-by: Ben Pfaff <blp@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-11-05openvswitch: Fix the type of struct ovs_key_nd nd_target field.Jarno Rajahalme
Should be the same as other IPv6 address fields. Current master produces sparse warnings without this change. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-11-05openvswitch: Add basic MPLS support to kernelSimon Horman
Allow datapath to recognize and extract MPLS labels into flow keys and execute actions which push, pop, and set labels on packets. Based heavily on work by Leo Alterman, Ravi K, Isaku Yamahata and Joe Stringer. Cc: Ravi K <rkerur@gmail.com> Cc: Leo Alterman <lalterman@nicira.com> Cc: Isaku Yamahata <yamahata@valinux.co.jp> Cc: Joe Stringer <joe@wand.net.nz> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-10-06openvswitch: Add support for Geneve tunneling.Jesse Gross
The Openvswitch implementation is completely agnostic to the options that are in use and can handle newly defined options without further work. It does this by simply matching on a byte array of options and allowing userspace to setup flows on this array. Signed-off-by: Jesse Gross <jesse@nicira.com> Singed-off-by: Ansis Atteka <aatteka@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Acked-by: Thomas Graf <tgraf@noironetworks.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06openvswitch: Wrap struct ovs_key_ipv4_tunnel in a new structure.Jesse Gross
Currently, the flow information that is matched for tunnels and the tunnel data passed around with packets is the same. However, as additional information is added this is not necessarily desirable, as in the case of pointers. This adds a new structure for tunnel metadata which currently contains only the existing struct. This change is purely internal to the kernel since the current OVS_KEY_ATTR_IPV4_TUNNEL is simply a compressed version of OVS_KEY_ATTR_TUNNEL that is translated at flow setup. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06openvswitch: Add support for matching on OAM packets.Jesse Gross
Some tunnel formats have mechanisms for indicating that packets are OAM frames that should be handled specially (either as high priority or not forwarded beyond an endpoint). This provides support for allowing those types of packets to be matched. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15openvswitch: Add recirc and hash action.Andy Zhou
Recirc action allows a packet to reenter openvswitch processing. currently openvswitch lookup flow for packet received and execute set of actions on that packet, with help of recirc action we can process/modify the packet and recirculate it back in openvswitch for another pass. OVS hash action calculates 5-tupple hash and set hash in flow-key hash. This can be used along with recirculation for distributing packets among different ports for bond devices. For example: OVS bonding can use following actions: Match on: bond flow; Action: hash, recirc(id) Match on: recirc-id == id and hash lower bits == a; Action: output port_bond_a Signed-off-by: Andy Zhou <azhou@nicira.com> Acked-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-07-24openvswitch: Allow each vport to have an array of 'port_id's.Alex Wang
In order to allow handlers directly read upcalls from datapath, we need to support per-handler netlink socket for each vport in datapath. This commit makes this happen. Also, it is guaranteed to be backward compatible with previous branch. Signed-off-by: Alex Wang <alexw@nicira.com> Acked-by: Thomas Graf <tgraf@redhat.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-05-22openvswitch: Avoid assigning a NULL pointer to flow actions.Jarno Rajahalme
Flow SET can accept an empty set of actions, with the intended semantics of leaving existing actions unmodified. This seems to have been brokin after OVS 1.7, as we have assigned the flow's actions pointer to NULL in this case, but we never check for the NULL pointer later on. This patch restores the intended behavior and documents it in the include/linux/openvswitch.h. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-01-06openvswitch: Drop user features if old user space attempted to create datapathThomas Graf
Drop user features if an outdated user space instance that does not understand the concept of user_features attempted to create a new datapath. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Jesse Gross <jesse@nicira.com>
2014-01-06openvswitch: Allow user space to announce ability to accept unaligned ↵Thomas Graf
Netlink messages Signed-off-by: Thomas Graf <tgraf@suug.ch> Reviewed-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-11-01openvswitch: TCP flags matching support.Jarno Rajahalme
tcp_flags=flags/mask Bitwise match on TCP flags. The flags and mask are 16-bit num‐ bers written in decimal or in hexadecimal prefixed by 0x. Each 1-bit in mask requires that the corresponding bit in port must match. Each 0-bit in mask causes the corresponding bit to be ignored. TCP protocol currently defines 9 flag bits, and additional 3 bits are reserved (must be transmitted as zero), see RFCs 793, 3168, and 3540. The flag bits are, numbering from the least significant bit: 0: FIN No more data from sender. 1: SYN Synchronize sequence numbers. 2: RST Reset the connection. 3: PSH Push function. 4: ACK Acknowledgement field significant. 5: URG Urgent pointer field significant. 6: ECE ECN Echo. 7: CWR Congestion Windows Reduced. 8: NS Nonce Sum. 9-11: Reserved. 12-15: Not matchable, must be zero. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-10-22openvswitch: collect mega flow mask statsAndy Zhou
Collect mega flow mask stats. ovs-dpctl show command can be used to display them for debugging and performance tuning. Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-08-26openvswitch: Add SCTP supportJoe Stringer
This patch adds support for rewriting SCTP src,dst ports similar to the functionality already available for TCP/UDP. Rewriting SCTP ports is expensive due to double-recalculation of the SCTP checksums; this is performed to ensure that packets traversing OVS with invalid checksums will continue to the destination with any checksum corruption intact. Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Joe Stringer <joe@wand.net.nz> Signed-off-by: Ben Pfaff <blp@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-08-23openvswitch: Mega flow implementationAndy Zhou
Add wildcarded flow support in kernel datapath. Wildcarded flow can improve OVS flow set up performance by avoid sending matching new flows to the user space program. The exact performance boost will largely dependent on wildcarded flow hit rate. In case all new flows hits wildcard flows, the flow set up rate is within 5% of that of linux bridge module. Pravin has made significant contributions to this patch. Including API clean ups and bug fixes. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-08-20openvswitch: Add vxlan tunneling support.Pravin B Shelar
Following patch adds vxlan vport type for openvswitch using vxlan api. So now there is vxlan dependency for openvswitch. CC: Jesse Gross <jesse@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19openvswitch: Add gre tunnel support.Pravin B Shelar
Add gre vport implementation. Most of gre protocol processing is pushed to gre module. It make use of gre demultiplexer therefore it can co-exist with linux device based gre tunnels. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19openvswitch: Add tunneling interface.Pravin B Shelar
Add ovs tunnel interface for set tunnel action for userspace. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-14openvswitch: Fix struct comment.Pravin B Shelar
Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-03-29openvswitch: Expose <linux/openvswitch.h> to userspaceThomas Graf
It contains the public netlink interface bits required by userspace to make use of the interface. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: Jesse Gross <jesse@nicira.com>