diff options
author | Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com> | 2024-11-20 08:43:20 +0100 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2024-12-02 08:41:16 -0800 |
commit | 752fddc0501c540214875b26bde2538f0a831811 (patch) | |
tree | 731ff84ab3724f4d8dd94d9c78d8ed769993a36d | |
parent | f4504af68575c1675235bacd8d36157cfc27ae5e (diff) |
selftests/bpf: document pseudo-header checksum helpers
network_helpers.h provides helpers to compute checksum for pseudo
headers but no helpers to compute the global checksums.
Before adding those, clarify csum_tcpudp_magic and csum_ipv6_magic
purpose by adding some documentation.
Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://lore.kernel.org/r/20241120-flow_dissector-v3-10-45b46494f937@bootlin.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
-rw-r--r-- | tools/testing/selftests/bpf/network_helpers.h | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index 0b2ed90c763f..00d6e7d52545 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -129,6 +129,21 @@ static inline __sum16 build_ip_csum(struct iphdr *iph) return csum_fold(sum); } +/** + * csum_tcpudp_magic - compute IP pseudo-header checksum + * + * Compute the IPv4 pseudo header checksum. The helper can take a + * accumulated sum from the transport layer to accumulate it and directly + * return the transport layer + * + * @saddr: IP source address + * @daddr: IP dest address + * @len: IP data size + * @proto: transport layer protocol + * @csum: The accumulated partial sum to add to the computation + * + * Returns the folded sum + */ static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len, __u8 proto, __wsum csum) @@ -144,6 +159,21 @@ static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, return csum_fold((__u32)s); } +/** + * csum_ipv6_magic - compute IPv6 pseudo-header checksum + * + * Compute the ipv6 pseudo header checksum. The helper can take a + * accumulated sum from the transport layer to accumulate it and directly + * return the transport layer + * + * @saddr: IPv6 source address + * @daddr: IPv6 dest address + * @len: IPv6 data size + * @proto: transport layer protocol + * @csum: The accumulated partial sum to add to the computation + * + * Returns the folded sum + */ static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr, __u32 len, __u8 proto, |