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authorLinus Torvalds <torvalds@linux-foundation.org>2015-09-26 13:01:33 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-26 13:01:33 +0300
commit518a7cb6980cd640c7f979d29021ad870f60d7d7 (patch)
tree7ef65013cbf1b5b3f65c8295756446dafcd4f784 /Documentation
parentd4a748a10e50d95992ae67677f1a1a13e2d6ed47 (diff)
parentbdb06cbf77cb01911694cc9076ffa8196b7b9b61 (diff)
downloadlinux-518a7cb6980cd640c7f979d29021ad870f60d7d7.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller: 1) When we run a tap on netlink sockets, we have to copy mmap'd SKBs instead of cloning them. From Daniel Borkmann. 2) When converting classical BPF into eBPF, fix the setting of the source reg to BPF_REG_X. From Tycho Andersen. 3) Fix igmpv3/mldv2 report parsing in the bridge multicast code, from Linus Lussing. 4) Fix dst refcounting for ipv6 tunnels, from Martin KaFai Lau. 5) Set NLM_F_REPLACE flag properly when replacing ipv6 routes, from Roopa Prabhu. 6) Add some new cxgb4 PCI device IDs, from Hariprasad Shenai. 7) Fix headroom tests and SKB leaks in ipv6 fragmentation code, from Florian Westphal. 8) Check DMA mapping errors in bna driver, from Ivan Vecera. 9) Several 8139cp bug fixes (dev_kfree_skb_any in interrupt context, misclearing of interrupt status in TX timeout handler, etc.) from David Woodhouse. 10) In tipc, reset SKB header pointer after skb_linearize(), from Erik Hugne. 11) Fix autobind races et al. in netlink code, from Herbert Xu with help from Tejun Heo and others. 12) Missing SET_NETDEV_DEV in sunvnet driver, from Sowmini Varadhan. 13) Fix various races in timewait timer and reqsk_queue_hadh_req, from Eric Dumazet. 14) Fix array overruns in mac80211, from Johannes Berg and Dan Carpenter. 15) Fix data race in rhashtable_rehash_one(), from Dmitriy Vyukov. 16) Fix race between poll_one_napi and napi_disable, from Neil Horman. 17) Fix byte order in geneve tunnel port config, from John W Linville. 18) Fix handling of ARP replies over lightweight tunnels, from Jiri Benc. 19) We can loop when fib rule dumps cross multiple SKBs, fix from Wilson Kok and Roopa Prabhu. 20) Several reference count handling bug fixes in the PHY/MDIO layer from Russel King. 21) Fix lockdep splat in ppp_dev_uninit(), from Guillaume Nault. 22) Fix crash in icmp_route_lookup(), from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits) net: Fix panic in icmp_route_lookup net: update docbook comment for __mdiobus_register() ppp: fix lockdep splat in ppp_dev_uninit() net: via/Kconfig: GENERIC_PCI_IOMAP required if PCI not selected phy: marvell: add link partner advertised modes net: fix net_device refcounting phy: add phy_device_remove() phy: fixed-phy: properly validate phy in fixed_phy_update_state() net: fix phy refcounting in a bunch of drivers of_mdio: fix MDIO phy device refcounting phy: add proper phy struct device refcounting phy: fix mdiobus module safety net: dsa: fix of_mdio_find_bus() device refcount leak phy: fix of_mdio_find_bus() device refcount leak ip6_tunnel: Reduce log level in ip6_tnl_err() to debug ip6_gre: Reduce log level in ip6gre_err() to debug fib_rules: fix fib rule dumps across multiple skbs bnx2x: byte swap rss_key to comply to Toeplitz specs net: revert "net_sched: move tp->root allocation into fw_init()" lwtunnel: remove source and destination UDP port config option ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/networking/vrf.txt96
-rw-r--r--Documentation/sysctl/net.txt16
2 files changed, 105 insertions, 7 deletions
diff --git a/Documentation/networking/vrf.txt b/Documentation/networking/vrf.txt
new file mode 100644
index 000000000000..031ef4a63485
--- /dev/null
+++ b/Documentation/networking/vrf.txt
@@ -0,0 +1,96 @@
+Virtual Routing and Forwarding (VRF)
+====================================
+The VRF device combined with ip rules provides the ability to create virtual
+routing and forwarding domains (aka VRFs, VRF-lite to be specific) in the
+Linux network stack. One use case is the multi-tenancy problem where each
+tenant has their own unique routing tables and in the very least need
+different default gateways.
+
+Processes can be "VRF aware" by binding a socket to the VRF device. Packets
+through the socket then use the routing table associated with the VRF
+device. An important feature of the VRF device implementation is that it
+impacts only Layer 3 and above so L2 tools (e.g., LLDP) are not affected
+(ie., they do not need to be run in each VRF). The design also allows
+the use of higher priority ip rules (Policy Based Routing, PBR) to take
+precedence over the VRF device rules directing specific traffic as desired.
+
+In addition, VRF devices allow VRFs to be nested within namespaces. For
+example network namespaces provide separation of network interfaces at L1
+(Layer 1 separation), VLANs on the interfaces within a namespace provide
+L2 separation and then VRF devices provide L3 separation.
+
+Design
+------
+A VRF device is created with an associated route table. Network interfaces
+are then enslaved to a VRF device:
+
+ +-----------------------------+
+ | vrf-blue | ===> route table 10
+ +-----------------------------+
+ | | |
+ +------+ +------+ +-------------+
+ | eth1 | | eth2 | ... | bond1 |
+ +------+ +------+ +-------------+
+ | |
+ +------+ +------+
+ | eth8 | | eth9 |
+ +------+ +------+
+
+Packets received on an enslaved device and are switched to the VRF device
+using an rx_handler which gives the impression that packets flow through
+the VRF device. Similarly on egress routing rules are used to send packets
+to the VRF device driver before getting sent out the actual interface. This
+allows tcpdump on a VRF device to capture all packets into and out of the
+VRF as a whole.[1] Similiarly, netfilter [2] and tc rules can be applied
+using the VRF device to specify rules that apply to the VRF domain as a whole.
+
+[1] Packets in the forwarded state do not flow through the device, so those
+ packets are not seen by tcpdump. Will revisit this limitation in a
+ future release.
+
+[2] Iptables on ingress is limited to NF_INET_PRE_ROUTING only with skb->dev
+ set to real ingress device and egress is limited to NF_INET_POST_ROUTING.
+ Will revisit this limitation in a future release.
+
+
+Setup
+-----
+1. VRF device is created with an association to a FIB table.
+ e.g, ip link add vrf-blue type vrf table 10
+ ip link set dev vrf-blue up
+
+2. Rules are added that send lookups to the associated FIB table when the
+ iif or oif is the VRF device. e.g.,
+ ip ru add oif vrf-blue table 10
+ ip ru add iif vrf-blue table 10
+
+ Set the default route for the table (and hence default route for the VRF).
+ e.g, ip route add table 10 prohibit default
+
+3. Enslave L3 interfaces to a VRF device.
+ e.g, ip link set dev eth1 master vrf-blue
+
+ Local and connected routes for enslaved devices are automatically moved to
+ the table associated with VRF device. Any additional routes depending on
+ the enslaved device will need to be reinserted following the enslavement.
+
+4. Additional VRF routes are added to associated table.
+ e.g., ip route add table 10 ...
+
+
+Applications
+------------
+Applications that are to work within a VRF need to bind their socket to the
+VRF device:
+
+ setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, dev, strlen(dev)+1);
+
+or to specify the output device using cmsg and IP_PKTINFO.
+
+
+Limitations
+-----------
+VRF device currently only works for IPv4. Support for IPv6 is under development.
+
+Index of original ingress interface is not available via cmsg. Will address
+soon.
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
index 6294b5186ae5..809ab6efcc74 100644
--- a/Documentation/sysctl/net.txt
+++ b/Documentation/sysctl/net.txt
@@ -54,13 +54,15 @@ default_qdisc
--------------
The default queuing discipline to use for network devices. This allows
-overriding the default queue discipline of pfifo_fast with an
-alternative. Since the default queuing discipline is created with the
-no additional parameters so is best suited to queuing disciplines that
-work well without configuration like stochastic fair queue (sfq),
-CoDel (codel) or fair queue CoDel (fq_codel). Don't use queuing disciplines
-like Hierarchical Token Bucket or Deficit Round Robin which require setting
-up classes and bandwidths.
+overriding the default of pfifo_fast with an alternative. Since the default
+queuing discipline is created without additional parameters so is best suited
+to queuing disciplines that work well without configuration like stochastic
+fair queue (sfq), CoDel (codel) or fair queue CoDel (fq_codel). Don't use
+queuing disciplines like Hierarchical Token Bucket or Deficit Round Robin
+which require setting up classes and bandwidths. Note that physical multiqueue
+interfaces still use mq as root qdisc, which in turn uses this default for its
+leaves. Virtual devices (like e.g. lo or veth) ignore this setting and instead
+default to noqueue.
Default: pfifo_fast
busy_read