diff options
| author | Stanislav Fomichev <sdf@google.com> | 2023-11-27 11:03:16 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-11-29 14:59:41 -0800 |
| commit | f6642de0c3e94d3ef6f44e127d11fcf4138873f7 (patch) | |
| tree | ed3f7280ac39e5502e48c08bbfff99e16467e896 | |
| parent | df3ed0003ec4994ce8ed4818c435c481281df89e (diff) | |
selftests/bpf: Add csum helpers
Checksum helpers will be used to calculate pseudo-header checksum in
AF_XDP metadata selftests.
The helpers are mirroring existing kernel ones:
- csum_tcpudp_magic : IPv4 pseudo header csum
- csum_ipv6_magic : IPv6 pseudo header csum
- csum_fold : fold csum and do one's complement
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231127190319.1190813-11-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | tools/testing/selftests/bpf/network_helpers.h | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index 34f1200a781b..94b9be24e39b 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -71,4 +71,47 @@ struct nstoken; */ struct nstoken *open_netns(const char *name); void close_netns(struct nstoken *token); + +static __u16 csum_fold(__u32 csum) +{ + csum = (csum & 0xffff) + (csum >> 16); + csum = (csum & 0xffff) + (csum >> 16); + + return (__u16)~csum; +} + +static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, + __u32 len, __u8 proto, + __wsum csum) +{ + __u64 s = csum; + + s += (__u32)saddr; + s += (__u32)daddr; + s += htons(proto + len); + s = (s & 0xffffffff) + (s >> 32); + s = (s & 0xffffffff) + (s >> 32); + + return csum_fold((__u32)s); +} + +static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, __u8 proto, + __wsum csum) +{ + __u64 s = csum; + int i; + + for (i = 0; i < 4; i++) + s += (__u32)saddr->s6_addr32[i]; + for (i = 0; i < 4; i++) + s += (__u32)daddr->s6_addr32[i]; + s += htons(proto + len); + s = (s & 0xffffffff) + (s >> 32); + s = (s & 0xffffffff) + (s >> 32); + + return csum_fold((__u32)s); +} + #endif |