selftests/bpf: Add BPF_FIB_LOOKUP_MARK tests

This patch extends the fib_lookup test suite by adding a few test
cases for each IP family to test the new BPF_FIB_LOOKUP_MARK flag
to the bpf_fib_lookup:

  * Test destination IP address selection with and without a mark
    and/or the BPF_FIB_LOOKUP_MARK flag set

Signed-off-by: Anton Protopopov <aspsk@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240326101742.17421-3-aspsk@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/fib_lookup.c b/tools/testing/selftests/bpf/prog_tests/fib_lookup.c
index 3379df2d4cf2521788aabe0588808074afdaacb6..bd76589580041fa2b743a87c0a1b44b44215e54b 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/fib_lookup.c
+++ b/tools/testing/selftests/bpf/prog_tests/fib_lookup.c
@@ -26,6 +26,17 @@
 #define IPV6_TBID_ADDR         "fd00::FFFF"
 #define IPV6_TBID_NET          "fd00::"
 #define IPV6_TBID_DST          "fd00::2"
+#define MARK_NO_POLICY         33
+#define MARK                   42
+#define MARK_TABLE             "200"
+#define IPV4_REMOTE_DST                "1.2.3.4"
+#define IPV4_LOCAL             "10.4.0.3"
+#define IPV4_GW1               "10.4.0.1"
+#define IPV4_GW2               "10.4.0.2"
+#define IPV6_REMOTE_DST                "be:ef::b0:10"
+#define IPV6_LOCAL             "fd01::3"
+#define IPV6_GW1               "fd01::1"
+#define IPV6_GW2               "fd01::2"
 #define DMAC                   "11:11:11:11:11:11"
 #define DMAC_INIT { 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, }
 #define DMAC2                  "01:01:01:01:01:01"
@@ -36,9 +47,11 @@ struct fib_lookup_test {
        const char *daddr;
        int expected_ret;
        const char *expected_src;
+       const char *expected_dst;
        int lookup_flags;
        __u32 tbid;
        __u8 dmac[6];
+       __u32 mark;
 };
 
 static const struct fib_lookup_test tests[] = {
@@ -90,10 +103,47 @@ static const struct fib_lookup_test tests[] = {
          .daddr = IPV6_ADDR_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
          .expected_src = IPV6_IFACE_ADDR_SEC,
          .lookup_flags = BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH, },
+       /* policy routing */
+       { .desc = "IPv4 policy routing, default",
+         .daddr = IPV4_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV4_GW1,
+         .lookup_flags = BPF_FIB_LOOKUP_MARK | BPF_FIB_LOOKUP_SKIP_NEIGH, },
+       { .desc = "IPv4 policy routing, mark doesn't point to a policy",
+         .daddr = IPV4_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV4_GW1,
+         .lookup_flags = BPF_FIB_LOOKUP_MARK | BPF_FIB_LOOKUP_SKIP_NEIGH,
+         .mark = MARK_NO_POLICY, },
+       { .desc = "IPv4 policy routing, mark points to a policy",
+         .daddr = IPV4_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV4_GW2,
+         .lookup_flags = BPF_FIB_LOOKUP_MARK | BPF_FIB_LOOKUP_SKIP_NEIGH,
+         .mark = MARK, },
+       { .desc = "IPv4 policy routing, mark points to a policy, but no flag",
+         .daddr = IPV4_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV4_GW1,
+         .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH,
+         .mark = MARK, },
+       { .desc = "IPv6 policy routing, default",
+         .daddr = IPV6_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV6_GW1,
+         .lookup_flags = BPF_FIB_LOOKUP_MARK | BPF_FIB_LOOKUP_SKIP_NEIGH, },
+       { .desc = "IPv6 policy routing, mark doesn't point to a policy",
+         .daddr = IPV6_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV6_GW1,
+         .lookup_flags = BPF_FIB_LOOKUP_MARK | BPF_FIB_LOOKUP_SKIP_NEIGH,
+         .mark = MARK_NO_POLICY, },
+       { .desc = "IPv6 policy routing, mark points to a policy",
+         .daddr = IPV6_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV6_GW2,
+         .lookup_flags = BPF_FIB_LOOKUP_MARK | BPF_FIB_LOOKUP_SKIP_NEIGH,
+         .mark = MARK, },
+       { .desc = "IPv6 policy routing, mark points to a policy, but no flag",
+         .daddr = IPV6_REMOTE_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
+         .expected_dst = IPV6_GW1,
+         .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH,
+         .mark = MARK, },
 };
 
-static int ifindex;
-
 static int setup_netns(void)
 {
        int err;
@@ -144,12 +194,24 @@ static int setup_netns(void)
        if (!ASSERT_OK(err, "write_sysctl(net.ipv6.conf.veth1.forwarding)"))
                goto fail;
 
+       /* Setup for policy routing tests */
+       SYS(fail, "ip addr add %s/24 dev veth1", IPV4_LOCAL);
+       SYS(fail, "ip addr add %s/64 dev veth1 nodad", IPV6_LOCAL);
+       SYS(fail, "ip route add %s/32 via %s", IPV4_REMOTE_DST, IPV4_GW1);
+       SYS(fail, "ip route add %s/32 via %s table %s", IPV4_REMOTE_DST, IPV4_GW2, MARK_TABLE);
+       SYS(fail, "ip -6 route add %s/128 via %s", IPV6_REMOTE_DST, IPV6_GW1);
+       SYS(fail, "ip -6 route add %s/128 via %s table %s", IPV6_REMOTE_DST, IPV6_GW2, MARK_TABLE);
+       SYS(fail, "ip rule add prio 2 fwmark %d lookup %s", MARK, MARK_TABLE);
+       SYS(fail, "ip -6 rule add prio 2 fwmark %d lookup %s", MARK, MARK_TABLE);
+
        return 0;
 fail:
        return -1;
 }
 
-static int set_lookup_params(struct bpf_fib_lookup *params, const struct fib_lookup_test *test)
+static int set_lookup_params(struct bpf_fib_lookup *params,
+                            const struct fib_lookup_test *test,
+                            int ifindex)
 {
        int ret;
 
@@ -158,6 +220,7 @@ static int set_lookup_params(struct bpf_fib_lookup *params, const struct fib_loo
        params->l4_protocol = IPPROTO_TCP;
        params->ifindex = ifindex;
        params->tbid = test->tbid;
+       params->mark = test->mark;
 
        if (inet_pton(AF_INET6, test->daddr, params->ipv6_dst) == 1) {
                params->family = AF_INET6;
@@ -190,40 +253,45 @@ static void mac_str(char *b, const __u8 *mac)
                mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
 }
 
-static void assert_src_ip(struct bpf_fib_lookup *fib_params, const char *expected_src)
+static void assert_ip_address(int family, void *addr, const char *expected_str)
 {
+       char str[INET6_ADDRSTRLEN];
+       u8 expected_addr[16];
+       int addr_len = 0;
        int ret;
-       __u32 src6[4];
-       __be32 src4;
 
-       switch (fib_params->family) {
+       switch (family) {
        case AF_INET6:
-               ret = inet_pton(AF_INET6, expected_src, src6);
-               ASSERT_EQ(ret, 1, "inet_pton(expected_src)");
-
-               ret = memcmp(src6, fib_params->ipv6_src, sizeof(fib_params->ipv6_src));
-               if (!ASSERT_EQ(ret, 0, "fib_lookup ipv6 src")) {
-                       char str_src6[64];
-
-                       inet_ntop(AF_INET6, fib_params->ipv6_src, str_src6,
-                                 sizeof(str_src6));
-                       printf("ipv6 expected %s actual %s ", expected_src,
-                              str_src6);
-               }
-
+               ret = inet_pton(AF_INET6, expected_str, expected_addr);
+               ASSERT_EQ(ret, 1, "inet_pton(AF_INET6, expected_str)");
+               addr_len = 16;
                break;
        case AF_INET:
-               ret = inet_pton(AF_INET, expected_src, &src4);
-               ASSERT_EQ(ret, 1, "inet_pton(expected_src)");
-
-               ASSERT_EQ(fib_params->ipv4_src, src4, "fib_lookup ipv4 src");
-
+               ret = inet_pton(AF_INET, expected_str, expected_addr);
+               ASSERT_EQ(ret, 1, "inet_pton(AF_INET, expected_str)");
+               addr_len = 4;
                break;
        default:
-               PRINT_FAIL("invalid addr family: %d", fib_params->family);
+               PRINT_FAIL("invalid address family: %d", family);
+               break;
+       }
+
+       if (memcmp(addr, expected_addr, addr_len)) {
+               inet_ntop(family, addr, str, sizeof(str));
+               PRINT_FAIL("expected %s actual %s ", expected_str, str);
        }
 }
 
+static void assert_src_ip(struct bpf_fib_lookup *params, const char *expected)
+{
+       assert_ip_address(params->family, params->ipv6_src, expected);
+}
+
+static void assert_dst_ip(struct bpf_fib_lookup *params, const char *expected)
+{
+       assert_ip_address(params->family, params->ipv6_dst, expected);
+}
+
 void test_fib_lookup(void)
 {
        struct bpf_fib_lookup *fib_params;
@@ -256,15 +324,18 @@ void test_fib_lookup(void)
        if (setup_netns())
                goto fail;
 
-       ifindex = if_nametoindex("veth1");
-       skb.ifindex = ifindex;
+       skb.ifindex = if_nametoindex("veth1");
+       if (!ASSERT_NEQ(skb.ifindex, 0, "if_nametoindex(veth1)"))
+               goto fail;
+
        fib_params = &skel->bss->fib_params;
 
        for (i = 0; i < ARRAY_SIZE(tests); i++) {
                printf("Testing %s ", tests[i].desc);
 
-               if (set_lookup_params(fib_params, &tests[i]))
+               if (set_lookup_params(fib_params, &tests[i], skb.ifindex))
                        continue;
+
                skel->bss->fib_lookup_ret = -1;
                skel->bss->lookup_flags = tests[i].lookup_flags;
 
@@ -278,6 +349,9 @@ void test_fib_lookup(void)
                if (tests[i].expected_src)
                        assert_src_ip(fib_params, tests[i].expected_src);
 
+               if (tests[i].expected_dst)
+                       assert_dst_ip(fib_params, tests[i].expected_dst);
+
                ret = memcmp(tests[i].dmac, fib_params->dmac, sizeof(tests[i].dmac));
                if (!ASSERT_EQ(ret, 0, "dmac not match")) {
                        char expected[18], actual[18];