On Mon, Mar 25, 2024 at 11:12:39AM -0700, Martin KaFai Lau wrote:
> On 3/24/24 8:04 AM, Anton Protopopov wrote:
> > 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.
>
> hmm... not sure I understand why it would get "final destination". Am I missing something?
> To be specific, there is no need to configure the IPV[46]_GW[12] address:
>
> - 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);
> 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);
>
> [root@arch-fb-vm1 ~]# ip netns exec fib_lookup_ns /bin/bash
>
> [root@arch-fb-vm1 ~]# ip -6 rule
> 0: from all lookup local
> 2: from all fwmark 0x2a lookup 200
> 32766: from all lookup main
>
> [root@arch-fb-vm1 ~]# ip -6 route show table main
> be:ef::b0:10 via fd01::1 dev veth3 metric 1024 linkdown pref medium
>
> [root@arch-fb-vm1 ~]# ip -6 route show table 200
> be:ef::b0:10 via fd01::2 dev veth3 metric 1024 linkdown pref medium
>
> [root@arch-fb-vm1 ~]# ip -6 route get be:ef::b0:10
> be:ef::b0:10 from :: via fd01::1 dev veth3 src fd01::3 metric 1024 pref medium
>
> [root@arch-fb-vm1 ~]# ip -6 route get be:ef::b0:10 mark 0x2a
> be:ef::b0:10 from :: via fd01::2 dev veth3 table 200 src fd01::3 metric 1024 pref medium
Ok, thanks. I will send a v2 with a simplified test
> >
> > 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);
> > >
> > >
>
