xdp_metadata test has a small helper computing ipv checksums to allow
manually building packets.

Move this helper to network_helpers to share it with other tests.

Signed-off-by: Alexis Lothoré (eBPF Foundation) <[email protected]>
---
Changes in v2:
- new patch
---
 tools/testing/selftests/bpf/network_helpers.h      | 23 ++++++++++++++++++++++
 .../selftests/bpf/prog_tests/xdp_metadata.c        | 19 +-----------------
 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/tools/testing/selftests/bpf/network_helpers.h 
b/tools/testing/selftests/bpf/network_helpers.h
index 
c72c16e1aff825439896b38e59962ffafe92dc71..c9b72960c651ab9fb249f6eb9e153b8416b7a488
 100644
--- a/tools/testing/selftests/bpf/network_helpers.h
+++ b/tools/testing/selftests/bpf/network_helpers.h
@@ -104,6 +104,29 @@ static __u16 csum_fold(__u32 csum)
        return (__u16)~csum;
 }
 
+static unsigned long add_csum_hword(const __u16 *start, int num_u16)
+{
+       unsigned long sum = 0;
+       int i;
+
+       for (i = 0; i < num_u16; i++)
+               sum += start[i];
+
+       return sum;
+}
+
+static inline __sum16 build_ip_csum(struct iphdr *iph)
+{
+       __u32 sum = 0;
+       __u16 *p;
+
+       iph->check = 0;
+       p = (void *)iph;
+       sum = add_csum_hword(p, iph->ihl << 1);
+
+       return csum_fold(sum);
+}
+
 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
                                        __u32 len, __u8 proto,
                                        __wsum csum)
diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c 
b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
index 
c87ee2bf558c1a7fb726cae0aa7b3d3735fb1aac..7f8e161655336127e5bd7a573d1a09db85a92f53
 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
@@ -133,23 +133,6 @@ static void close_xsk(struct xsk *xsk)
        munmap(xsk->umem_area, UMEM_SIZE);
 }
 
-static void ip_csum(struct iphdr *iph)
-{
-       __u32 sum = 0;
-       __u16 *p;
-       int i;
-
-       iph->check = 0;
-       p = (void *)iph;
-       for (i = 0; i < sizeof(*iph) / sizeof(*p); i++)
-               sum += p[i];
-
-       while (sum >> 16)
-               sum = (sum & 0xffff) + (sum >> 16);
-
-       iph->check = ~sum;
-}
-
 static int generate_packet(struct xsk *xsk, __u16 dst_port)
 {
        struct xsk_tx_metadata *meta;
@@ -192,7 +175,7 @@ static int generate_packet(struct xsk *xsk, __u16 dst_port)
        iph->protocol = IPPROTO_UDP;
        ASSERT_EQ(inet_pton(FAMILY, TX_ADDR, &iph->saddr), 1, 
"inet_pton(TX_ADDR)");
        ASSERT_EQ(inet_pton(FAMILY, RX_ADDR, &iph->daddr), 1, 
"inet_pton(RX_ADDR)");
-       ip_csum(iph);
+       iph->check = build_ip_csum(iph);
 
        udph->source = htons(UDP_SOURCE_PORT);
        udph->dest = htons(dst_port);

-- 
2.47.0


Reply via email to