From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ... --- Documentation/networking/ila.rst | 296 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 296 insertions(+) create mode 100644 Documentation/networking/ila.rst (limited to 'Documentation/networking/ila.rst') diff --git a/Documentation/networking/ila.rst b/Documentation/networking/ila.rst new file mode 100644 index 000000000..5ac0a6270 --- /dev/null +++ b/Documentation/networking/ila.rst @@ -0,0 +1,296 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=================================== +Identifier Locator Addressing (ILA) +=================================== + + +Introduction +============ + +Identifier-locator addressing (ILA) is a technique used with IPv6 that +differentiates between location and identity of a network node. Part of an +address expresses the immutable identity of the node, and another part +indicates the location of the node which can be dynamic. Identifier-locator +addressing can be used to efficiently implement overlay networks for +network virtualization as well as solutions for use cases in mobility. + +ILA can be thought of as means to implement an overlay network without +encapsulation. This is accomplished by performing network address +translation on destination addresses as a packet traverses a network. To +the network, an ILA translated packet appears to be no different than any +other IPv6 packet. For instance, if the transport protocol is TCP then an +ILA translated packet looks like just another TCP/IPv6 packet. The +advantage of this is that ILA is transparent to the network so that +optimizations in the network, such as ECMP, RSS, GRO, GSO, etc., just work. + +The ILA protocol is described in Internet-Draft draft-herbert-intarea-ila. + + +ILA terminology +=============== + + - Identifier + A number that identifies an addressable node in the network + independent of its location. ILA identifiers are sixty-four + bit values. + + - Locator + A network prefix that routes to a physical host. Locators + provide the topological location of an addressed node. ILA + locators are sixty-four bit prefixes. + + - ILA mapping + A mapping of an ILA identifier to a locator (or to a + locator and meta data). An ILA domain maintains a database + that contains mappings for all destinations in the domain. + + - SIR address + An IPv6 address composed of a SIR prefix (upper sixty- + four bits) and an identifier (lower sixty-four bits). + SIR addresses are visible to applications and provide a + means for them to address nodes independent of their + location. + + - ILA address + An IPv6 address composed of a locator (upper sixty-four + bits) and an identifier (low order sixty-four bits). ILA + addresses are never visible to an application. + + - ILA host + An end host that is capable of performing ILA translations + on transmit or receive. + + - ILA router + A network node that performs ILA translation and forwarding + of translated packets. + + - ILA forwarding cache + A type of ILA router that only maintains a working set + cache of mappings. + + - ILA node + A network node capable of performing ILA translations. This + can be an ILA router, ILA forwarding cache, or ILA host. + + +Operation +========= + +There are two fundamental operations with ILA: + + - Translate a SIR address to an ILA address. This is performed on ingress + to an ILA overlay. + + - Translate an ILA address to a SIR address. This is performed on egress + from the ILA overlay. + +ILA can be deployed either on end hosts or intermediate devices in the +network; these are provided by "ILA hosts" and "ILA routers" respectively. +Configuration and datapath for these two points of deployment is somewhat +different. + +The diagram below illustrates the flow of packets through ILA as well +as showing ILA hosts and routers:: + + +--------+ +--------+ + | Host A +-+ +--->| Host B | + | | | (2) ILA (') | | + +--------+ | ...addressed.... ( ) +--------+ + V +---+--+ . packet . +---+--+ (_) + (1) SIR | | ILA |----->-------->---->| ILA | | (3) SIR + addressed +->|router| . . |router|->-+ addressed + packet +---+--+ . IPv6 . +---+--+ packet + / . Network . + / . . +--+-++--------+ + +--------+ / . . |ILA || Host | + | Host +--+ . .- -|host|| | + | | . . +--+-++--------+ + +--------+ ................ + + +Transport checksum handling +=========================== + +When an address is translated by ILA, an encapsulated transport checksum +that includes the translated address in a pseudo header may be rendered +incorrect on the wire. This is a problem for intermediate devices, +including checksum offload in NICs, that process the checksum. There are +three options to deal with this: + +- no action Allow the checksum to be incorrect on the wire. Before + a receiver verifies a checksum the ILA to SIR address + translation must be done. + +- adjust transport checksum + When ILA translation is performed the packet is parsed + and if a transport layer checksum is found then it is + adjusted to reflect the correct checksum per the + translated address. + +- checksum neutral mapping + When an address is translated the difference can be offset + elsewhere in a part of the packet that is covered by + the checksum. The low order sixteen bits of the identifier + are used. This method is preferred since it doesn't require + parsing a packet beyond the IP header and in most cases the + adjustment can be precomputed and saved with the mapping. + +Note that the checksum neutral adjustment affects the low order sixteen +bits of the identifier. When ILA to SIR address translation is done on +egress the low order bits are restored to the original value which +restores the identifier as it was originally sent. + + +Identifier types +================ + +ILA defines different types of identifiers for different use cases. + +The defined types are: + + 0: interface identifier + + 1: locally unique identifier + + 2: virtual networking identifier for IPv4 address + + 3: virtual networking identifier for IPv6 unicast address + + 4: virtual networking identifier for IPv6 multicast address + + 5: non-local address identifier + +In the current implementation of kernel ILA only locally unique identifiers +(LUID) are supported. LUID allows for a generic, unformatted 64 bit +identifier. + + +Identifier formats +================== + +Kernel ILA supports two optional fields in an identifier for formatting: +"C-bit" and "identifier type". The presence of these fields is determined +by configuration as demonstrated below. + +If the identifier type is present it occupies the three highest order +bits of an identifier. The possible values are given in the above list. + +If the C-bit is present, this is used as an indication that checksum +neutral mapping has been done. The C-bit can only be set in an +ILA address, never a SIR address. + +In the simplest format the identifier types, C-bit, and checksum +adjustment value are not present so an identifier is considered an +unstructured sixty-four bit value:: + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Identifier | + + + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +The checksum neutral adjustment may be configured to always be +present using neutral-map-auto. In this case there is no C-bit, but the +checksum adjustment is in the low order 16 bits. The identifier is +still sixty-four bits:: + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Identifier | + | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | Checksum-neutral adjustment | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +The C-bit may used to explicitly indicate that checksum neutral +mapping has been applied to an ILA address. The format is:: + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | |C| Identifier | + | +-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | Checksum-neutral adjustment | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +The identifier type field may be present to indicate the identifier +type. If it is not present then the type is inferred based on mapping +configuration. The checksum neutral adjustment may automatically +used with the identifier type as illustrated below:: + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Type| Identifier | + +-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | Checksum-neutral adjustment | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +If the identifier type and the C-bit can be present simultaneously so +the identifier format would be:: + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Type|C| Identifier | + +-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | Checksum-neutral adjustment | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + +Configuration +============= + +There are two methods to configure ILA mappings. One is by using LWT routes +and the other is ila_xlat (called from NFHOOK PREROUTING hook). ila_xlat +is intended to be used in the receive path for ILA hosts . + +An ILA router has also been implemented in XDP. Description of that is +outside the scope of this document. + +The usage of for ILA LWT routes is: + +ip route add DEST/128 encap ila LOC csum-mode MODE ident-type TYPE via ADDR + +Destination (DEST) can either be a SIR address (for an ILA host or ingress +ILA router) or an ILA address (egress ILA router). LOC is the sixty-four +bit locator (with format W:X:Y:Z) that overwrites the upper sixty-four +bits of the destination address. Checksum MODE is one of "no-action", +"adj-transport", "neutral-map", and "neutral-map-auto". If neutral-map is +set then the C-bit will be present. Identifier TYPE one of "luid" or +"use-format." In the case of use-format, the identifier type field is +present and the effective type is taken from that. + +The usage of ila_xlat is: + +ip ila add loc_match MATCH loc LOC csum-mode MODE ident-type TYPE + +MATCH indicates the incoming locator that must be matched to apply +a the translaiton. LOC is the locator that overwrites the upper +sixty-four bits of the destination address. MODE and TYPE have the +same meanings as described above. + + +Some examples +============= + +:: + + # Configure an ILA route that uses checksum neutral mapping as well + # as type field. Note that the type field is set in the SIR address + # (the 2000 implies type is 1 which is LUID). + ip route add 3333:0:0:1:2000:0:1:87/128 encap ila 2001:0:87:0 \ + csum-mode neutral-map ident-type use-format + + # Configure an ILA LWT route that uses auto checksum neutral mapping + # (no C-bit) and configure identifier type to be LUID so that the + # identifier type field will not be present. + ip route add 3333:0:0:1:2000:0:2:87/128 encap ila 2001:0:87:1 \ + csum-mode neutral-map-auto ident-type luid + + ila_xlat configuration + + # Configure an ILA to SIR mapping that matches a locator and overwrites + # it with a SIR address (3333:0:0:1 in this example). The C-bit and + # identifier field are used. + ip ila add loc_match 2001:0:119:0 loc 3333:0:0:1 \ + csum-mode neutral-map-auto ident-type use-format + + # Configure an ILA to SIR mapping where checksum neutral is automatically + # set without the C-bit and the identifier type is configured to be LUID + # so that the identifier type field is not present. + ip ila add loc_match 2001:0:119:0 loc 3333:0:0:1 \ + csum-mode neutral-map-auto ident-type use-format -- cgit v1.2.3