mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-28 00:48:07 -04:00
ff1f56d987
David Ahern says: ==================== Provide a helper for doing a FIB and neighbor lookup in the kernel tables from an XDP program. The helper provides a fastpath for forwarding packets. If the packet is a local delivery or for any reason is not a simple lookup and forward, the packet is expected to continue up the stack for full processing. The response from a FIB and neighbor lookup is either the egress index with the bpf_fib_lookup struct filled in with dmac and gateway or 0 meaning the packet should continue up the stack. In time we can revisit this to return the FIB lookup result errno if it is one of the special RTN_'s such as RTN_BLACKHOLE (-EINVAL) so that the XDP programs can do an early drop if desired. Patches 1-6 do some more refactoring to IPv6 with the end goal of extracting a FIB lookup function that aligns with fib_lookup for IPv4, basically returning a fib6_info without creating a dst based entry. Patch 7 adds lookup functions to the ipv6 stub. These are needed since bpf is built into the kernel and ipv6 may not be built or loaded. Patch 8 adds the bpf helper and 9 adds a sample program. v3 - remove ETH_ALEN and in6_addr from uapi header v2 - removed pkt_access from bpf_func_proto as noticed by Daniel - added check in that IPv6 forwarding is enabled - added DaveM's ack on patches 1-7 and 9 based on v1 response and fact that no changes were made to them in v2 v1 - updated commit messages and cover letter - added comment to sample program noting lack of verification on egress device supporting XDP RFC v2 - fixed use of foward helper from cls_act as noted by Daniel - in patch 1 rename fib6_lookup_1 as well for consistency ==================== Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.