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| author | Toke Høiland-Jørgensen <toke@redhat.com> | 2020-10-20 23:25:56 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2020-10-22 01:28:54 +0200 |
| commit | ba452c9e996d8a4c347b32805f91abb70de5de7e (patch) | |
| tree | 7cc639674290dda9b607ed44dc572b30f55502a7 /tools | |
| parent | c5eb48e89286510d638844104a6f6582a4838a32 (diff) | |
| download | linux-ba452c9e996d8a4c347b32805f91abb70de5de7e.tar.gz linux-ba452c9e996d8a4c347b32805f91abb70de5de7e.tar.bz2 linux-ba452c9e996d8a4c347b32805f91abb70de5de7e.zip | |
bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop
Based on the discussion in [0], update the bpf_redirect_neigh() helper to
accept an optional parameter specifying the nexthop information. This makes
it possible to combine bpf_fib_lookup() and bpf_redirect_neigh() without
incurring a duplicate FIB lookup - since the FIB lookup helper will return
the nexthop information even if no neighbour is present, this can simply
be passed on to bpf_redirect_neigh() if bpf_fib_lookup() returns
BPF_FIB_LKUP_RET_NO_NEIGH. Thus fix & extend it before helper API is frozen.
[0] https://lore.kernel.org/bpf/393e17fc-d187-3a8d-2f0d-a627c7c63fca@iogearbox.net/
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/bpf/160322915615.32199.1187570224032024535.stgit@toke.dk
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/include/uapi/linux/bpf.h | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index bf5a99d803e4..e6ceac3f7d62 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3677,15 +3677,19 @@ union bpf_attr { * Return * The id is returned or 0 in case the id could not be retrieved. * - * long bpf_redirect_neigh(u32 ifindex, u64 flags) + * long bpf_redirect_neigh(u32 ifindex, struct bpf_redir_neigh *params, int plen, u64 flags) * Description * Redirect the packet to another net device of index *ifindex* * and fill in L2 addresses from neighboring subsystem. This helper * is somewhat similar to **bpf_redirect**\ (), except that it * populates L2 addresses as well, meaning, internally, the helper - * performs a FIB lookup based on the skb's networking header to - * get the address of the next hop and then relies on the neighbor - * lookup for the L2 address of the nexthop. + * relies on the neighbor lookup for the L2 address of the nexthop. + * + * The helper will perform a FIB lookup based on the skb's + * networking header to get the address of the next hop, unless + * this is supplied by the caller in the *params* argument. The + * *plen* argument indicates the len of *params* and should be set + * to 0 if *params* is NULL. * * The *flags* argument is reserved and must be 0. The helper is * currently only supported for tc BPF program types, and enabled @@ -4906,6 +4910,16 @@ struct bpf_fib_lookup { __u8 dmac[6]; /* ETH_ALEN */ }; +struct bpf_redir_neigh { + /* network family for lookup (AF_INET, AF_INET6) */ + __u32 nh_family; + /* network address of nexthop; skips fib lookup to find gateway */ + union { + __be32 ipv4_nh; + __u32 ipv6_nh[4]; /* in6_addr; network order */ + }; +}; + enum bpf_task_fd_type { BPF_FD_TYPE_RAW_TRACEPOINT, /* tp name */ BPF_FD_TYPE_TRACEPOINT, /* tp name */ |