Merge branch 'ipv6-ioam'
Justin Iurman says:
====================
Support for the IOAM Pre-allocated Trace with IPv6
v5:
- Refine types, min/max and default values for new sysctls
- Introduce a "_wide" sysctl for each "ioam6_id" sysctl
- Add more validation on headers before processing data
- RCU for sc <> ns pointers + appropriate accessors
- Generic Netlink policies are now per op, not per family anymore
- Address other comments/remarks from Jakub (thanks again)
- Revert "__packed" to "__attribute__((packed))" for uapi headers
- Add tests to cover the functionality added, as requested by David Ahern
v4:
- Address warnings from checkpatch (ignore errors related to unnamed bitfields
in the first patch)
- Use of hweight32 (thanks Jakub)
- Remove inline keyword from static functions in C files and let the compiler
decide what to do (thanks Jakub)
v3:
- Fix warning "unused label 'out_unregister_genl'" by adding conditional macro
- Fix lwtunnel output redirect bug: dst cache useless in this case, use
orig_output instead
v2:
- Fix warning with static for __ioam6_fill_trace_data
- Fix sparse warning with __force when casting __be64 to __be32
- Fix unchecked dereference when removing IOAM namespaces or schemas
- exthdrs.c: Don't drop by default (now: ignore) to match the act bits "00"
- Add control plane support for the inline insertion (lwtunnel)
- Provide uapi structures
- Use __net_timestamp if skb->tstamp is empty
- Add note about the temporary IANA allocation
- Remove support for "removable" TLVs
- Remove support for virtual/anonymous tunnel decapsulation
In-situ Operations, Administration, and Maintenance (IOAM) records
operational and telemetry information in a packet while it traverses
a path between two points in an IOAM domain. It is defined in
draft-ietf-ippm-ioam-data [1]. IOAM data fields can be encapsulated
into a variety of protocols. The IPv6 encapsulation is defined in
draft-ietf-ippm-ioam-ipv6-options [2], via extension headers. IOAM
can be used to complement OAM mechanisms based on e.g. ICMP or other
types of probe packets.
This patchset implements support for the Pre-allocated Trace, carried
by a Hop-by-Hop. Therefore, a new IPv6 Hop-by-Hop TLV option is
introduced, see IANA [3]. The three other IOAM options are not included
in this patchset (Incremental Trace, Proof-of-Transit and Edge-to-Edge).
The main idea behind the IOAM Pre-allocated Trace is that a node
pre-allocates some room in packets for IOAM data. Then, each IOAM node
on the path will insert its data. There exist several interesting use-
cases, e.g. Fast failure detection/isolation or Smart service selection.
Another killer use-case is what we have called Cross-Layer Telemetry,
see the demo video on its repository [4], that aims to make the entire
stack (L2/L3 -> L7) visible for distributed tracing tools (e.g. Jaeger),
instead of the current L5 -> L7 limited view. So, basically, this is a
nice feature for the Linux Kernel.
This patchset also provides support for the control plane part, but only for the
inline insertion (host-to-host use case), through lightweight tunnels. Indeed,
for in-transit traffic, the solution is to have an IPv6-in-IPv6 encapsulation,
which brings some difficulties and still requires a little bit of work and
discussion (ie anonymous tunnel decapsulation and multi egress resolution).
- Patch 1: IPv6 IOAM headers definition
- Patch 2: Data plane support for Pre-allocated Trace
- Patch 3: IOAM Generic Netlink API
- Patch 4: Support for IOAM injection with lwtunnels
- Patch 5: Documentation for new IOAM sysctls
- Patch 6: Test for the IOAM insertion with IPv6
[1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data
[2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options
[3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2
[4] https://github.com/iurmanj/cross-layer-telemetry
====================
Signed-off-by: David S. Miller <davem@davemloft.net>