linux/tools/include
Christian Ehrig e26aa600ba bpf: Add flag BPF_F_NO_TUNNEL_KEY to bpf_skb_set_tunnel_key()
This patch allows to remove TUNNEL_KEY from the tunnel flags bitmap
when using bpf_skb_set_tunnel_key by providing a BPF_F_NO_TUNNEL_KEY
flag. On egress, the resulting tunnel header will not contain a tunnel
key if the protocol and implementation supports it.

At the moment bpf_tunnel_key wants a user to specify a numeric tunnel
key. This will wrap the inner packet into a tunnel header with the key
bit and value set accordingly. This is problematic when using a tunnel
protocol that supports optional tunnel keys and a receiving tunnel
device that is not expecting packets with the key bit set. The receiver
won't decapsulate and drop the packet.

RFC 2890 and RFC 2784 GRE tunnels are examples where this flag is
useful. It allows for generating packets, that can be decapsulated by
a GRE tunnel device not operating in collect metadata mode or not
expecting the key bit set.

Signed-off-by: Christian Ehrig <cehrig@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221218051734.31411-1-cehrig@cloudflare.com
2022-12-19 23:53:15 +01:00
..
asm nds32: Remove the architecture 2022-03-07 13:54:59 +01:00
asm-generic hugetlb_encode.h: fix undefined behaviour (34 << 26) 2022-10-03 14:02:55 -07:00
linux - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
nolibc tools/nolibc/string: Fix memcmp() implementation 2022-10-28 15:07:02 -07:00
tools tools include: add dis-asm-compat.h to handle version differences 2022-08-01 15:29:49 -03:00
trace/events
uapi bpf: Add flag BPF_F_NO_TUNNEL_KEY to bpf_skb_set_tunnel_key() 2022-12-19 23:53:15 +01:00
vdso tools headers: Synchronize linux/bits.h with the kernel sources 2020-04-14 11:40:05 -03:00