selftests/bpf: test_xdp_veth: Use int to describe next veth

In the struct veth_configuration, the next_veth string is used to tell
the next virtual interface to which packets must be redirected to. So it
has to match the local_veth string of an other veth_configuration.

Change next_veth type to int to avoid handling two identical strings.
This integer is used as an offset in the network configuration table.

Signed-off-by: Bastien Curutchet (eBPF Foundation) <bastien.curutchet@bootlin.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250131-redirect-multi-v4-4-970b33678512@bootlin.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c b/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
index d41884fdc430f1ceed53f16b0dddbdbb34f83301..942c6e99e15ef69003c033e7bc1bfc9bc9777557 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
+++ b/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
@@ -39,7 +39,7 @@ struct veth_configuration {
        char local_veth[VETH_NAME_MAX_LEN]; /* Interface in main namespace */
        char remote_veth[VETH_NAME_MAX_LEN]; /* Peer interface in dedicated namespace*/
        const char *namespace; /* Namespace for the remote veth */
-       char next_veth[VETH_NAME_MAX_LEN]; /* Local interface to redirect traffic to */
+       int next_veth; /* Local interface to redirect traffic to */
        char *remote_addr; /* IP address of the remote veth */
 };
 
@@ -47,21 +47,21 @@ static struct veth_configuration config[VETH_PAIRS_COUNT] = {
        {
                .local_veth = "veth1",
                .remote_veth = "veth11",
-               .next_veth = "veth2",
+               .next_veth = 1,
                .remote_addr = IP_SRC,
                .namespace = "ns-veth11"
        },
        {
                .local_veth = "veth2",
                .remote_veth = "veth22",
-               .next_veth = "veth3",
+               .next_veth = 2,
                .remote_addr = NULL,
                .namespace = "ns-veth22"
        },
        {
                .local_veth = "veth3",
                .remote_veth = "veth33",
-               .next_veth = "veth1",
+               .next_veth = 0,
                .remote_addr = IP_DST,
                .namespace = "ns-veth33"
        }
@@ -144,7 +144,9 @@ static int configure_network(struct skeletons *skeletons)
        if (!ASSERT_GE(map_fd, 0, "open redirect map"))
                goto fail;
        for (i = 0; i < VETH_PAIRS_COUNT; i++) {
-               interface_id = if_nametoindex(config[i].next_veth);
+               int next_veth = config[i].next_veth;
+
+               interface_id = if_nametoindex(config[next_veth].local_veth);
                if (!ASSERT_NEQ(interface_id, 0, "non zero interface index"))
                        goto fail;
                err = bpf_map_update_elem(map_fd, &i, &interface_id, BPF_ANY);