On Sat, Mar 23, 2024 at 03:34:10PM -0700, Martin KaFai Lau wrote:
> On 3/22/24 7:02 AM, Anton Protopopov wrote:
> > 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
> >
> > To test this functionality another network namespace and a new veth
> > pair were added to the test.
> >
>
> [ ... ]
>
> > static const struct fib_lookup_test tests[] = {
> > @@ -90,10 +105,47 @@ 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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .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, .ifname = "veth3",
> > + .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH,
> > + .mark = MARK, },
> > };
> > -static int ifindex;
> > -
> > static int setup_netns(void)
> > {
> > int err;
> > @@ -144,12 +196,40 @@ 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 link add veth3 type veth peer name veth4");
> > + SYS(fail, "ip link set dev veth3 up");
> > + SYS(fail, "ip link set dev veth4 netns %s up", NS_REMOTE);
> > +
> > + SYS(fail, "ip addr add %s/24 dev veth3", IPV4_LOCAL);
> > + SYS(fail, "ip netns exec %s ip addr add %s/24 dev veth4", NS_REMOTE, IPV4_GW1);
> > + SYS(fail, "ip netns exec %s ip addr add %s/24 dev veth4", NS_REMOTE, IPV4_GW2);
> > + SYS(fail, "ip addr add %s/64 dev veth3 nodad", IPV6_LOCAL);
> > + SYS(fail, "ip netns exec %s ip addr add %s/64 dev veth4 nodad", NS_REMOTE, IPV6_GW1);
> > + SYS(fail, "ip netns exec %s ip addr add %s/64 dev veth4 nodad", NS_REMOTE, IPV6_GW2);
>
> Trying to see if the setup can be simplified.
>
> Does it need to add another netns and setup a reachable IPV[46]_GW[12] gateway?
>
> The test is not sending any traffic and it is a BPF_FIB_LOOKUP_SKIP_NEIGH test.
I think this will not work without another namespace, as FIB lookup will
return DST="final destination", not DST="gateway", as the gateway is in the
same namespace and can be skipped.
Instead of adding a new namespace I can move the second interface to the
root namespace. This will work, but then we're interfering with the root
namespace.
> > + 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);
> > +
> > + err = write_sysctl("/proc/sys/net/ipv4/conf/veth3/forwarding", "1");
> > + if (!ASSERT_OK(err, "write_sysctl(net.ipv4.conf.veth3.forwarding)"))
> > + goto fail;
> > +
> > + err = write_sysctl("/proc/sys/net/ipv6/conf/veth3/forwarding", "1");
> > + if (!ASSERT_OK(err, "write_sysctl(net.ipv6.conf.veth3.forwarding)"))
> > + goto fail;
> > +
> > return 0;
> > fail:
> > return -1;
> > }
>
> [ ... ]
>
> > @@ -248,6 +337,7 @@ void test_fib_lookup(void)
> > prog_fd = bpf_program__fd(skel->progs.fib_lookup);
> > SYS(fail, "ip netns add %s", NS_TEST);
> > + SYS(fail, "ip netns add %s", NS_REMOTE);
>
>
