selftests/bpf: test_xdp_veth: Add XDP broadcast redirection tests

XDP redirections with BPF_F_BROADCAST and BPF_F_EXCLUDE_INGRESS flags
are tested by test_xdp_redirect_multi.sh but not within the test_progs
framework.

Add a broadcast test case in test_xdp_veth.c to test them.
Use the same BPF programs than the one used by
test_xdp_redirect_multi.sh.
Use a BPF map to select the broadcast flags.
Use a BPF map with an entry per veth to check whether packets are
received or not

Signed-off-by: Bastien Curutchet (eBPF Foundation) <bastien.curutchet@bootlin.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250212-redirect-multi-v5-4-fd0d39fca6e6@bootlin.com

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 a1c79af23bec25529af5b549d16b2cbfaf1cebd4..3ca308aac75413af6bcaf69ed8d50f74b5325206 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
+++ b/tools/testing/selftests/bpf/prog_tests/test_xdp_veth.c
@@ -28,6 +28,23 @@
  *      | |                | |                | |
  *      | ------------------ ------------------ |
  *      -----------------------------------------
+ *
+ * - [test_xdp_veth_broadcast_redirect]: broadcast from veth11
+ *     - IPv4 ping : BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS
+ *          -> echo request received by all except veth11
+ *     - IPv4 ping : BPF_F_BROADCAST
+ *          -> echo request received by all veth
+ *
+ *    veth11             veth22              veth33
+ *  (XDP_PASS)         (XDP_PASS)          (XDP_PASS)
+ *       |                  |                  |
+ *       |                  |                  |
+ *     veth1             veth2              veth3
+ * (XDP_REDIRECT)     (XDP_REDIRECT)     (XDP_REDIRECT)
+ *      |                   ^                  ^
+ *      |                   |                  |
+ *      ----------------------------------------
+ *
  */
 
 #define _GNU_SOURCE
@@ -36,6 +53,7 @@
 #include "network_helpers.h"
 #include "xdp_dummy.skel.h"
 #include "xdp_redirect_map.skel.h"
+#include "xdp_redirect_multi_kern.skel.h"
 #include "xdp_tx.skel.h"
 #include <uapi/linux/if_link.h>
 
@@ -44,6 +62,7 @@
 #define IP_MAX_LEN             16
 #define IP_SRC                         "10.1.1.11"
 #define IP_DST                         "10.1.1.33"
+#define IP_NEIGH                       "10.1.1.253"
 #define PROG_NAME_MAX_LEN      128
 #define NS_NAME_MAX_LEN                32
 
@@ -297,6 +316,121 @@ destroy_xdp_dummy:
        cleanup_network(&net_config);
 }
 
+#define BROADCAST_REDIRECT_SKEL_NB     2
+static void xdp_veth_broadcast_redirect(u32 attach_flags, u64 redirect_flags)
+{
+       struct prog_configuration prog_cfg[VETH_PAIRS_COUNT] = {
+               {
+                       .local_name = "xdp_redirect_map_multi_prog",
+                       .remote_name = "xdp_count_0",
+                       .local_flags = attach_flags,
+                       .remote_flags = attach_flags,
+               },
+               {
+                       .local_name = "xdp_redirect_map_multi_prog",
+                       .remote_name = "xdp_count_1",
+                       .local_flags = attach_flags,
+                       .remote_flags = attach_flags,
+               },
+               {
+                       .local_name = "xdp_redirect_map_multi_prog",
+                       .remote_name = "xdp_count_2",
+                       .local_flags = attach_flags,
+                       .remote_flags = attach_flags,
+               }
+       };
+       struct bpf_object *bpf_objs[BROADCAST_REDIRECT_SKEL_NB];
+       struct xdp_redirect_multi_kern *xdp_redirect_multi_kern;
+       struct xdp_redirect_map *xdp_redirect_map;
+       struct bpf_devmap_val devmap_val = {};
+       struct net_configuration net_config;
+       struct nstoken *nstoken = NULL;
+       u16 protocol = ETH_P_IP;
+       int group_map;
+       int flags_map;
+       int cnt_map;
+       u64 cnt = 0;
+       int i, err;
+
+       xdp_redirect_multi_kern = xdp_redirect_multi_kern__open_and_load();
+       if (!ASSERT_OK_PTR(xdp_redirect_multi_kern, "xdp_redirect_multi_kern__open_and_load"))
+               return;
+
+       xdp_redirect_map = xdp_redirect_map__open_and_load();
+       if (!ASSERT_OK_PTR(xdp_redirect_map, "xdp_redirect_map__open_and_load"))
+               goto destroy_xdp_redirect_multi_kern;
+
+       if (!ASSERT_OK(create_network(&net_config), "create network"))
+               goto destroy_xdp_redirect_map;
+
+       group_map = bpf_map__fd(xdp_redirect_multi_kern->maps.map_all);
+       if (!ASSERT_OK_FD(group_map, "open map_all"))
+               goto destroy_xdp_redirect_map;
+
+       flags_map = bpf_map__fd(xdp_redirect_multi_kern->maps.redirect_flags);
+       if (!ASSERT_OK_FD(group_map, "open map_all"))
+               goto destroy_xdp_redirect_map;
+
+       err = bpf_map_update_elem(flags_map, &protocol, &redirect_flags, BPF_NOEXIST);
+       if (!ASSERT_OK(err, "init IP count"))
+               goto destroy_xdp_redirect_map;
+
+       cnt_map = bpf_map__fd(xdp_redirect_map->maps.rxcnt);
+       if (!ASSERT_OK_FD(cnt_map, "open rxcnt map"))
+               goto destroy_xdp_redirect_map;
+
+       bpf_objs[0] = xdp_redirect_multi_kern->obj;
+       bpf_objs[1] = xdp_redirect_map->obj;
+
+       nstoken = open_netns(net_config.ns0_name);
+       if (!ASSERT_OK_PTR(nstoken, "open NS0"))
+               goto destroy_xdp_redirect_map;
+
+       for (i = 0; i < VETH_PAIRS_COUNT; i++) {
+               int ifindex = if_nametoindex(net_config.veth_cfg[i].local_veth);
+
+               if (attach_programs_to_veth_pair(bpf_objs, BROADCAST_REDIRECT_SKEL_NB,
+                                                &net_config, prog_cfg, i))
+                       goto destroy_xdp_redirect_map;
+
+               SYS(destroy_xdp_redirect_map,
+                   "ip -n %s neigh add %s lladdr 00:00:00:00:00:01 dev %s",
+                   net_config.veth_cfg[i].namespace, IP_NEIGH, net_config.veth_cfg[i].remote_veth);
+
+               devmap_val.ifindex = ifindex;
+               err = bpf_map_update_elem(group_map, &ifindex, &devmap_val, 0);
+               if (!ASSERT_OK(err, "bpf_map_update_elem"))
+                       goto destroy_xdp_redirect_map;
+
+       }
+
+       SYS_NOFAIL("ip netns exec %s ping %s -i 0.1 -c 4 -W1 > /dev/null ",
+                   net_config.veth_cfg[0].namespace, IP_NEIGH);
+
+       for (i = 0; i < VETH_PAIRS_COUNT; i++) {
+               err =  bpf_map_lookup_elem(cnt_map, &i, &cnt);
+               if (!ASSERT_OK(err, "get IP cnt"))
+                       goto destroy_xdp_redirect_map;
+
+               if (redirect_flags & BPF_F_EXCLUDE_INGRESS)
+                       /* veth11 shouldn't receive the ICMP requests;
+                        * others should
+                        */
+                       ASSERT_EQ(cnt, i ? 4 : 0, "compare IP cnt");
+               else
+                       /* All remote veth should receive the ICMP requests */
+                       ASSERT_EQ(cnt, 4, "compare IP cnt");
+       }
+
+destroy_xdp_redirect_map:
+       close_netns(nstoken);
+       xdp_redirect_map__destroy(xdp_redirect_map);
+destroy_xdp_redirect_multi_kern:
+       xdp_redirect_multi_kern__destroy(xdp_redirect_multi_kern);
+
+       cleanup_network(&net_config);
+}
+
 void test_xdp_veth_redirect(void)
 {
        if (test__start_subtest("0"))
@@ -308,3 +442,26 @@ void test_xdp_veth_redirect(void)
        if (test__start_subtest("SKB_MODE"))
                xdp_veth_redirect(XDP_FLAGS_SKB_MODE);
 }
+
+void test_xdp_veth_broadcast_redirect(void)
+{
+       if (test__start_subtest("0/BROADCAST"))
+               xdp_veth_broadcast_redirect(0, BPF_F_BROADCAST);
+
+       if (test__start_subtest("0/(BROADCAST | EXCLUDE_INGRESS)"))
+               xdp_veth_broadcast_redirect(0, BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS);
+
+       if (test__start_subtest("DRV_MODE/BROADCAST"))
+               xdp_veth_broadcast_redirect(XDP_FLAGS_DRV_MODE, BPF_F_BROADCAST);
+
+       if (test__start_subtest("DRV_MODE/(BROADCAST | EXCLUDE_INGRESS)"))
+               xdp_veth_broadcast_redirect(XDP_FLAGS_DRV_MODE,
+                                           BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS);
+
+       if (test__start_subtest("SKB_MODE/BROADCAST"))
+               xdp_veth_broadcast_redirect(XDP_FLAGS_SKB_MODE, BPF_F_BROADCAST);
+
+       if (test__start_subtest("SKB_MODE/(BROADCAST | EXCLUDE_INGRESS)"))
+               xdp_veth_broadcast_redirect(XDP_FLAGS_SKB_MODE,
+                                           BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS);
+}

diff --git a/tools/testing/selftests/bpf/progs/xdp_redirect_map.c b/tools/testing/selftests/bpf/progs/xdp_redirect_map.c
index 682dda8dabbc9abbb5d1b0b22dd5f81124142e79..93f31480246118529a6b536775c9641c286e46d8 100644 (file)
--- a/tools/testing/selftests/bpf/progs/xdp_redirect_map.c
+++ b/tools/testing/selftests/bpf/progs/xdp_redirect_map.c
@@ -1,7 +1,10 @@
 // SPDX-License-Identifier: GPL-2.0
 
+#include <linux/if_ether.h>
+
 #include <linux/bpf.h>
 #include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
 
 struct {
        __uint(type, BPF_MAP_TYPE_DEVMAP);
@@ -28,4 +31,49 @@ int xdp_redirect_map_2(struct xdp_md *xdp)
        return bpf_redirect_map(&tx_port, 2, 0);
 }
 
+struct {
+       __uint(type, BPF_MAP_TYPE_ARRAY);
+       __uint(max_entries, 3);
+       __type(key, __u32);
+       __type(value, __u64);
+} rxcnt SEC(".maps");
+
+static int xdp_count(struct xdp_md *xdp, __u32 key)
+{
+       void *data_end = (void *)(long)xdp->data_end;
+       void *data = (void *)(long)xdp->data;
+       struct ethhdr *eth = data;
+       __u64 *count;
+
+       if (data + sizeof(*eth) > data_end)
+               return XDP_DROP;
+
+       if (bpf_htons(eth->h_proto) == ETH_P_IP) {
+               /* We only count IPv4 packets */
+               count = bpf_map_lookup_elem(&rxcnt, &key);
+               if (count)
+                       *count += 1;
+       }
+
+       return XDP_PASS;
+}
+
+SEC("xdp")
+int xdp_count_0(struct xdp_md *xdp)
+{
+       return xdp_count(xdp, 0);
+}
+
+SEC("xdp")
+int xdp_count_1(struct xdp_md *xdp)
+{
+       return xdp_count(xdp, 1);
+}
+
+SEC("xdp")
+int xdp_count_2(struct xdp_md *xdp)
+{
+       return xdp_count(xdp, 2);
+}
+
 char _license[] SEC("license") = "GPL";