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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/networking/xfrm_sync.rst | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
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().
...
Diffstat (limited to 'Documentation/networking/xfrm_sync.rst')
-rw-r--r-- | Documentation/networking/xfrm_sync.rst | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/Documentation/networking/xfrm_sync.rst b/Documentation/networking/xfrm_sync.rst new file mode 100644 index 000000000..6246503ce --- /dev/null +++ b/Documentation/networking/xfrm_sync.rst @@ -0,0 +1,189 @@ +.. SPDX-License-Identifier: GPL-2.0 + +==== +XFRM +==== + +The sync patches work is based on initial patches from +Krisztian <hidden@balabit.hu> and others and additional patches +from Jamal <hadi@cyberus.ca>. + +The end goal for syncing is to be able to insert attributes + generate +events so that the SA can be safely moved from one machine to another +for HA purposes. +The idea is to synchronize the SA so that the takeover machine can do +the processing of the SA as accurate as possible if it has access to it. + +We already have the ability to generate SA add/del/upd events. +These patches add ability to sync and have accurate lifetime byte (to +ensure proper decay of SAs) and replay counters to avoid replay attacks +with as minimal loss at failover time. +This way a backup stays as closely up-to-date as an active member. + +Because the above items change for every packet the SA receives, +it is possible for a lot of the events to be generated. +For this reason, we also add a nagle-like algorithm to restrict +the events. i.e we are going to set thresholds to say "let me +know if the replay sequence threshold is reached or 10 secs have passed" +These thresholds are set system-wide via sysctls or can be updated +per SA. + +The identified items that need to be synchronized are: +- the lifetime byte counter +note that: lifetime time limit is not important if you assume the failover +machine is known ahead of time since the decay of the time countdown +is not driven by packet arrival. +- the replay sequence for both inbound and outbound + +1) Message Structure +---------------------- + +nlmsghdr:aevent_id:optional-TLVs. + +The netlink message types are: + +XFRM_MSG_NEWAE and XFRM_MSG_GETAE. + +A XFRM_MSG_GETAE does not have TLVs. + +A XFRM_MSG_NEWAE will have at least two TLVs (as is +discussed further below). + +aevent_id structure looks like:: + + struct xfrm_aevent_id { + struct xfrm_usersa_id sa_id; + xfrm_address_t saddr; + __u32 flags; + __u32 reqid; + }; + +The unique SA is identified by the combination of xfrm_usersa_id, +reqid and saddr. + +flags are used to indicate different things. The possible +flags are:: + + XFRM_AE_RTHR=1, /* replay threshold*/ + XFRM_AE_RVAL=2, /* replay value */ + XFRM_AE_LVAL=4, /* lifetime value */ + XFRM_AE_ETHR=8, /* expiry timer threshold */ + XFRM_AE_CR=16, /* Event cause is replay update */ + XFRM_AE_CE=32, /* Event cause is timer expiry */ + XFRM_AE_CU=64, /* Event cause is policy update */ + +How these flags are used is dependent on the direction of the +message (kernel<->user) as well the cause (config, query or event). +This is described below in the different messages. + +The pid will be set appropriately in netlink to recognize direction +(0 to the kernel and pid = processid that created the event +when going from kernel to user space) + +A program needs to subscribe to multicast group XFRMNLGRP_AEVENTS +to get notified of these events. + +2) TLVS reflect the different parameters: +----------------------------------------- + +a) byte value (XFRMA_LTIME_VAL) + +This TLV carries the running/current counter for byte lifetime since +last event. + +b)replay value (XFRMA_REPLAY_VAL) + +This TLV carries the running/current counter for replay sequence since +last event. + +c)replay threshold (XFRMA_REPLAY_THRESH) + +This TLV carries the threshold being used by the kernel to trigger events +when the replay sequence is exceeded. + +d) expiry timer (XFRMA_ETIMER_THRESH) + +This is a timer value in milliseconds which is used as the nagle +value to rate limit the events. + +3) Default configurations for the parameters: +--------------------------------------------- + +By default these events should be turned off unless there is +at least one listener registered to listen to the multicast +group XFRMNLGRP_AEVENTS. + +Programs installing SAs will need to specify the two thresholds, however, +in order to not change existing applications such as racoon +we also provide default threshold values for these different parameters +in case they are not specified. + +the two sysctls/proc entries are: + +a) /proc/sys/net/core/sysctl_xfrm_aevent_etime +used to provide default values for the XFRMA_ETIMER_THRESH in incremental +units of time of 100ms. The default is 10 (1 second) + +b) /proc/sys/net/core/sysctl_xfrm_aevent_rseqth +used to provide default values for XFRMA_REPLAY_THRESH parameter +in incremental packet count. The default is two packets. + +4) Message types +---------------- + +a) XFRM_MSG_GETAE issued by user-->kernel. + XFRM_MSG_GETAE does not carry any TLVs. + +The response is a XFRM_MSG_NEWAE which is formatted based on what +XFRM_MSG_GETAE queried for. + +The response will always have XFRMA_LTIME_VAL and XFRMA_REPLAY_VAL TLVs. +* if XFRM_AE_RTHR flag is set, then XFRMA_REPLAY_THRESH is also retrieved +* if XFRM_AE_ETHR flag is set, then XFRMA_ETIMER_THRESH is also retrieved + +b) XFRM_MSG_NEWAE is issued by either user space to configure + or kernel to announce events or respond to a XFRM_MSG_GETAE. + +i) user --> kernel to configure a specific SA. + +any of the values or threshold parameters can be updated by passing the +appropriate TLV. + +A response is issued back to the sender in user space to indicate success +or failure. + +In the case of success, additionally an event with +XFRM_MSG_NEWAE is also issued to any listeners as described in iii). + +ii) kernel->user direction as a response to XFRM_MSG_GETAE + +The response will always have XFRMA_LTIME_VAL and XFRMA_REPLAY_VAL TLVs. + +The threshold TLVs will be included if explicitly requested in +the XFRM_MSG_GETAE message. + +iii) kernel->user to report as event if someone sets any values or + thresholds for an SA using XFRM_MSG_NEWAE (as described in #i above). + In such a case XFRM_AE_CU flag is set to inform the user that + the change happened as a result of an update. + The message will always have XFRMA_LTIME_VAL and XFRMA_REPLAY_VAL TLVs. + +iv) kernel->user to report event when replay threshold or a timeout + is exceeded. + +In such a case either XFRM_AE_CR (replay exceeded) or XFRM_AE_CE (timeout +happened) is set to inform the user what happened. +Note the two flags are mutually exclusive. +The message will always have XFRMA_LTIME_VAL and XFRMA_REPLAY_VAL TLVs. + +Exceptions to threshold settings +-------------------------------- + +If you have an SA that is getting hit by traffic in bursts such that +there is a period where the timer threshold expires with no packets +seen, then an odd behavior is seen as follows: +The first packet arrival after a timer expiry will trigger a timeout +event; i.e we don't wait for a timeout period or a packet threshold +to be reached. This is done for simplicity and efficiency reasons. + +-JHS |