^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) .. SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) ===================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) Identifier Locator Addressing (ILA)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) ===================================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) Introduction
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) ============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) Identifier-locator addressing (ILA) is a technique used with IPv6 that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) differentiates between location and identity of a network node. Part of an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) address expresses the immutable identity of the node, and another part
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) indicates the location of the node which can be dynamic. Identifier-locator
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) addressing can be used to efficiently implement overlay networks for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) network virtualization as well as solutions for use cases in mobility.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) ILA can be thought of as means to implement an overlay network without
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) encapsulation. This is accomplished by performing network address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) translation on destination addresses as a packet traverses a network. To
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) the network, an ILA translated packet appears to be no different than any
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) other IPv6 packet. For instance, if the transport protocol is TCP then an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) ILA translated packet looks like just another TCP/IPv6 packet. The
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) advantage of this is that ILA is transparent to the network so that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) optimizations in the network, such as ECMP, RSS, GRO, GSO, etc., just work.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) The ILA protocol is described in Internet-Draft draft-herbert-intarea-ila.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) ILA terminology
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) ===============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) - Identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) A number that identifies an addressable node in the network
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) independent of its location. ILA identifiers are sixty-four
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) bit values.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) - Locator
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) A network prefix that routes to a physical host. Locators
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) provide the topological location of an addressed node. ILA
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) locators are sixty-four bit prefixes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) - ILA mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) A mapping of an ILA identifier to a locator (or to a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) locator and meta data). An ILA domain maintains a database
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) that contains mappings for all destinations in the domain.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) - SIR address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) An IPv6 address composed of a SIR prefix (upper sixty-
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) four bits) and an identifier (lower sixty-four bits).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) SIR addresses are visible to applications and provide a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) means for them to address nodes independent of their
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) location.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) - ILA address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) An IPv6 address composed of a locator (upper sixty-four
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) bits) and an identifier (low order sixty-four bits). ILA
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) addresses are never visible to an application.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) - ILA host
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) An end host that is capable of performing ILA translations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) on transmit or receive.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) - ILA router
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) A network node that performs ILA translation and forwarding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) of translated packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) - ILA forwarding cache
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) A type of ILA router that only maintains a working set
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) cache of mappings.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) - ILA node
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) A network node capable of performing ILA translations. This
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) can be an ILA router, ILA forwarding cache, or ILA host.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) Operation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) =========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) There are two fundamental operations with ILA:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) - Translate a SIR address to an ILA address. This is performed on ingress
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) to an ILA overlay.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) - Translate an ILA address to a SIR address. This is performed on egress
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) from the ILA overlay.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) ILA can be deployed either on end hosts or intermediate devices in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) network; these are provided by "ILA hosts" and "ILA routers" respectively.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) Configuration and datapath for these two points of deployment is somewhat
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) different.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) The diagram below illustrates the flow of packets through ILA as well
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) as showing ILA hosts and routers::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) +--------+ +--------+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) | Host A +-+ +--->| Host B |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) | | | (2) ILA (') | |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) +--------+ | ...addressed.... ( ) +--------+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) V +---+--+ . packet . +---+--+ (_)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) (1) SIR | | ILA |----->-------->---->| ILA | | (3) SIR
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) addressed +->|router| . . |router|->-+ addressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) packet +---+--+ . IPv6 . +---+--+ packet
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) / . Network .
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) / . . +--+-++--------+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) +--------+ / . . |ILA || Host |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) | Host +--+ . .- -|host|| |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) | | . . +--+-++--------+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) +--------+ ................
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) Transport checksum handling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) ===========================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) When an address is translated by ILA, an encapsulated transport checksum
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) that includes the translated address in a pseudo header may be rendered
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) incorrect on the wire. This is a problem for intermediate devices,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) including checksum offload in NICs, that process the checksum. There are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) three options to deal with this:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) - no action Allow the checksum to be incorrect on the wire. Before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) a receiver verifies a checksum the ILA to SIR address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) translation must be done.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) - adjust transport checksum
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) When ILA translation is performed the packet is parsed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) and if a transport layer checksum is found then it is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) adjusted to reflect the correct checksum per the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) translated address.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) - checksum neutral mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) When an address is translated the difference can be offset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) elsewhere in a part of the packet that is covered by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) the checksum. The low order sixteen bits of the identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) are used. This method is preferred since it doesn't require
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) parsing a packet beyond the IP header and in most cases the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) adjustment can be precomputed and saved with the mapping.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) Note that the checksum neutral adjustment affects the low order sixteen
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) bits of the identifier. When ILA to SIR address translation is done on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) egress the low order bits are restored to the original value which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) restores the identifier as it was originally sent.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) Identifier types
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) ================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) ILA defines different types of identifiers for different use cases.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) The defined types are:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 0: interface identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 1: locally unique identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 2: virtual networking identifier for IPv4 address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 3: virtual networking identifier for IPv6 unicast address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 4: virtual networking identifier for IPv6 multicast address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 5: non-local address identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) In the current implementation of kernel ILA only locally unique identifiers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) (LUID) are supported. LUID allows for a generic, unformatted 64 bit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) identifier.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) Identifier formats
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) ==================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) Kernel ILA supports two optional fields in an identifier for formatting:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) "C-bit" and "identifier type". The presence of these fields is determined
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) by configuration as demonstrated below.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) If the identifier type is present it occupies the three highest order
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) bits of an identifier. The possible values are given in the above list.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) If the C-bit is present, this is used as an indication that checksum
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) neutral mapping has been done. The C-bit can only be set in an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) ILA address, never a SIR address.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) In the simplest format the identifier types, C-bit, and checksum
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) adjustment value are not present so an identifier is considered an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) unstructured sixty-four bit value::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) | Identifier |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) + +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) | |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) The checksum neutral adjustment may be configured to always be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) present using neutral-map-auto. In this case there is no C-bit, but the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) checksum adjustment is in the low order 16 bits. The identifier is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) still sixty-four bits::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) | Identifier |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) | | Checksum-neutral adjustment |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) The C-bit may used to explicitly indicate that checksum neutral
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) mapping has been applied to an ILA address. The format is::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) | |C| Identifier |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) | +-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) | | Checksum-neutral adjustment |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) The identifier type field may be present to indicate the identifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) type. If it is not present then the type is inferred based on mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) configuration. The checksum neutral adjustment may automatically
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) used with the identifier type as illustrated below::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) | Type| Identifier |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) +-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) | | Checksum-neutral adjustment |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) If the identifier type and the C-bit can be present simultaneously so
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) the identifier format would be::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) | Type|C| Identifier |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) +-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) | | Checksum-neutral adjustment |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) Configuration
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) =============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) There are two methods to configure ILA mappings. One is by using LWT routes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) and the other is ila_xlat (called from NFHOOK PREROUTING hook). ila_xlat
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) is intended to be used in the receive path for ILA hosts .
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) An ILA router has also been implemented in XDP. Description of that is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) outside the scope of this document.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) The usage of for ILA LWT routes is:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) ip route add DEST/128 encap ila LOC csum-mode MODE ident-type TYPE via ADDR
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) Destination (DEST) can either be a SIR address (for an ILA host or ingress
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) ILA router) or an ILA address (egress ILA router). LOC is the sixty-four
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) bit locator (with format W:X:Y:Z) that overwrites the upper sixty-four
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) bits of the destination address. Checksum MODE is one of "no-action",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) "adj-transport", "neutral-map", and "neutral-map-auto". If neutral-map is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) set then the C-bit will be present. Identifier TYPE one of "luid" or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) "use-format." In the case of use-format, the identifier type field is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) present and the effective type is taken from that.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) The usage of ila_xlat is:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) ip ila add loc_match MATCH loc LOC csum-mode MODE ident-type TYPE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) MATCH indicates the incoming locator that must be matched to apply
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) a the translaiton. LOC is the locator that overwrites the upper
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) sixty-four bits of the destination address. MODE and TYPE have the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) same meanings as described above.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) Some examples
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) =============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) ::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) # Configure an ILA route that uses checksum neutral mapping as well
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) # as type field. Note that the type field is set in the SIR address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) # (the 2000 implies type is 1 which is LUID).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) ip route add 3333:0:0:1:2000:0:1:87/128 encap ila 2001:0:87:0 \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) csum-mode neutral-map ident-type use-format
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) # Configure an ILA LWT route that uses auto checksum neutral mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) # (no C-bit) and configure identifier type to be LUID so that the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) # identifier type field will not be present.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) ip route add 3333:0:0:1:2000:0:2:87/128 encap ila 2001:0:87:1 \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) csum-mode neutral-map-auto ident-type luid
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) ila_xlat configuration
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) # Configure an ILA to SIR mapping that matches a locator and overwrites
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) # it with a SIR address (3333:0:0:1 in this example). The C-bit and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) # identifier field are used.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) ip ila add loc_match 2001:0:119:0 loc 3333:0:0:1 \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) csum-mode neutral-map-auto ident-type use-format
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) # Configure an ILA to SIR mapping where checksum neutral is automatically
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) # set without the C-bit and the identifier type is configured to be LUID
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) # so that the identifier type field is not present.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) ip ila add loc_match 2001:0:119:0 loc 3333:0:0:1 \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) csum-mode neutral-map-auto ident-type use-format
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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