selftests/bpf: Add vrf_socket_lookup tests

Verify that socket lookup via TC/XDP with all BPF APIs is VRF aware.

Signed-off-by: Gilad Sever <gilad9366@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Eyal Birger <eyal.birger@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230621104211.301902-5-gilad9366@gmail.com

diff --git a/tools/testing/selftests/bpf/prog_tests/vrf_socket_lookup.c b/tools/testing/selftests/bpf/prog_tests/vrf_socket_lookup.c
new file mode 100644 (file)
index 0000000..2a5e207
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/vrf_socket_lookup.c
@@ -0,0 +1,312 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+
+/*
+ * Topology:
+ * ---------
+ *     NS0 namespace         |   NS1 namespace
+ *                          |
+ *     +--------------+      |   +--------------+
+ *     |    veth01    |----------|    veth10    |
+ *     | 172.16.1.100 |      |   | 172.16.1.200 |
+ *     |     bpf      |      |   +--------------+
+ *     +--------------+      |
+ *      server(UDP/TCP)      |
+ *  +-------------------+    |
+ *  |        vrf1       |    |
+ *  |  +--------------+ |    |   +--------------+
+ *  |  |    veth02    |----------|    veth20    |
+ *  |  | 172.16.2.100 | |    |   | 172.16.2.200 |
+ *  |  |     bpf      | |    |   +--------------+
+ *  |  +--------------+ |    |
+ *  |   server(UDP/TCP) |    |
+ *  +-------------------+    |
+ *
+ * Test flow
+ * -----------
+ *  The tests verifies that socket lookup via TC is VRF aware:
+ *  1) Creates two veth pairs between NS0 and NS1:
+ *     a) veth01 <-> veth10 outside the VRF
+ *     b) veth02 <-> veth20 in the VRF
+ *  2) Attaches to veth01 and veth02 a program that calls:
+ *     a) bpf_skc_lookup_tcp() with TCP and tcp_skc is true
+ *     b) bpf_sk_lookup_tcp() with TCP and tcp_skc is false
+ *     c) bpf_sk_lookup_udp() with UDP
+ *     The program stores the lookup result in bss->lookup_status.
+ *  3) Creates a socket TCP/UDP server in/outside the VRF.
+ *  4) The test expects lookup_status to be:
+ *     a) 0 from device in VRF to server outside VRF
+ *     b) 0 from device outside VRF to server in VRF
+ *     c) 1 from device in VRF to server in VRF
+ *     d) 1 from device outside VRF to server outside VRF
+ */
+
+#include <net/if.h>
+
+#include "test_progs.h"
+#include "network_helpers.h"
+#include "vrf_socket_lookup.skel.h"
+
+#define NS0 "vrf_socket_lookup_0"
+#define NS1 "vrf_socket_lookup_1"
+
+#define IP4_ADDR_VETH01 "172.16.1.100"
+#define IP4_ADDR_VETH10 "172.16.1.200"
+#define IP4_ADDR_VETH02 "172.16.2.100"
+#define IP4_ADDR_VETH20 "172.16.2.200"
+
+#define NON_VRF_PORT 5000
+#define IN_VRF_PORT 5001
+
+#define TIMEOUT_MS 3000
+
+static int make_socket(int sotype, const char *ip, int port,
+                      struct sockaddr_storage *addr)
+{
+       int err, fd;
+
+       err = make_sockaddr(AF_INET, ip, port, addr, NULL);
+       if (!ASSERT_OK(err, "make_address"))
+               return -1;
+
+       fd = socket(AF_INET, sotype, 0);
+       if (!ASSERT_GE(fd, 0, "socket"))
+               return -1;
+
+       if (!ASSERT_OK(settimeo(fd, TIMEOUT_MS), "settimeo"))
+               goto fail;
+
+       return fd;
+fail:
+       close(fd);
+       return -1;
+}
+
+static int make_server(int sotype, const char *ip, int port, const char *ifname)
+{
+       int err, fd = -1;
+
+       fd = start_server(AF_INET, sotype, ip, port, TIMEOUT_MS);
+       if (!ASSERT_GE(fd, 0, "start_server"))
+               return -1;
+
+       if (ifname) {
+               err = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
+                                ifname, strlen(ifname) + 1);
+               if (!ASSERT_OK(err, "setsockopt(SO_BINDTODEVICE)"))
+                       goto fail;
+       }
+
+       return fd;
+fail:
+       close(fd);
+       return -1;
+}
+
+static int attach_progs(char *ifname, int tc_prog_fd, int xdp_prog_fd)
+{
+       LIBBPF_OPTS(bpf_tc_hook, hook, .attach_point = BPF_TC_INGRESS);
+       LIBBPF_OPTS(bpf_tc_opts, opts, .handle = 1, .priority = 1,
+                   .prog_fd = tc_prog_fd);
+       int ret, ifindex;
+
+       ifindex = if_nametoindex(ifname);
+       if (!ASSERT_NEQ(ifindex, 0, "if_nametoindex"))
+               return -1;
+       hook.ifindex = ifindex;
+
+       ret = bpf_tc_hook_create(&hook);
+       if (!ASSERT_OK(ret, "bpf_tc_hook_create"))
+               return ret;
+
+       ret = bpf_tc_attach(&hook, &opts);
+       if (!ASSERT_OK(ret, "bpf_tc_attach")) {
+               bpf_tc_hook_destroy(&hook);
+               return ret;
+       }
+       ret = bpf_xdp_attach(ifindex, xdp_prog_fd, 0, NULL);
+       if (!ASSERT_OK(ret, "bpf_xdp_attach")) {
+               bpf_tc_hook_destroy(&hook);
+               return ret;
+       }
+
+       return 0;
+}
+
+static void cleanup(void)
+{
+       SYS_NOFAIL("test -f /var/run/netns/" NS0 " && ip netns delete "
+                  NS0);
+       SYS_NOFAIL("test -f /var/run/netns/" NS1 " && ip netns delete "
+                  NS1);
+}
+
+static int setup(struct vrf_socket_lookup *skel)
+{
+       int tc_prog_fd, xdp_prog_fd, ret = 0;
+       struct nstoken *nstoken = NULL;
+
+       SYS(fail, "ip netns add " NS0);
+       SYS(fail, "ip netns add " NS1);
+
+       /* NS0 <-> NS1 [veth01 <-> veth10] */
+       SYS(fail, "ip link add veth01 netns " NS0 " type veth peer name veth10"
+           " netns " NS1);
+       SYS(fail, "ip -net " NS0 " addr add " IP4_ADDR_VETH01 "/24 dev veth01");
+       SYS(fail, "ip -net " NS0 " link set dev veth01 up");
+       SYS(fail, "ip -net " NS1 " addr add " IP4_ADDR_VETH10 "/24 dev veth10");
+       SYS(fail, "ip -net " NS1 " link set dev veth10 up");
+
+       /* NS0 <-> NS1 [veth02 <-> veth20] */
+       SYS(fail, "ip link add veth02 netns " NS0 " type veth peer name veth20"
+           " netns " NS1);
+       SYS(fail, "ip -net " NS0 " addr add " IP4_ADDR_VETH02 "/24 dev veth02");
+       SYS(fail, "ip -net " NS0 " link set dev veth02 up");
+       SYS(fail, "ip -net " NS1 " addr add " IP4_ADDR_VETH20 "/24 dev veth20");
+       SYS(fail, "ip -net " NS1 " link set dev veth20 up");
+
+       /* veth02 -> vrf1  */
+       SYS(fail, "ip -net " NS0 " link add vrf1 type vrf table 11");
+       SYS(fail, "ip -net " NS0 " route add vrf vrf1 unreachable default"
+           " metric 4278198272");
+       SYS(fail, "ip -net " NS0 " link set vrf1 alias vrf");
+       SYS(fail, "ip -net " NS0 " link set vrf1 up");
+       SYS(fail, "ip -net " NS0 " link set veth02 master vrf1");
+
+       /* Attach TC and XDP progs to veth devices in NS0 */
+       nstoken = open_netns(NS0);
+       if (!ASSERT_OK_PTR(nstoken, "setns " NS0))
+               goto fail;
+       tc_prog_fd = bpf_program__fd(skel->progs.tc_socket_lookup);
+       if (!ASSERT_GE(tc_prog_fd, 0, "bpf_program__tc_fd"))
+               goto fail;
+       xdp_prog_fd = bpf_program__fd(skel->progs.xdp_socket_lookup);
+       if (!ASSERT_GE(xdp_prog_fd, 0, "bpf_program__xdp_fd"))
+               goto fail;
+
+       if (attach_progs("veth01", tc_prog_fd, xdp_prog_fd))
+               goto fail;
+
+       if (attach_progs("veth02", tc_prog_fd, xdp_prog_fd))
+               goto fail;
+
+       goto close;
+fail:
+       ret = -1;
+close:
+       if (nstoken)
+               close_netns(nstoken);
+       return ret;
+}
+
+static int test_lookup(struct vrf_socket_lookup *skel, int sotype,
+                      const char *ip, int port, bool test_xdp, bool tcp_skc,
+                      int lookup_status_exp)
+{
+       static const char msg[] = "Hello Server";
+       struct sockaddr_storage addr = {};
+       int fd, ret = 0;
+
+       fd = make_socket(sotype, ip, port, &addr);
+       if (fd < 0)
+               return -1;
+
+       skel->bss->test_xdp = test_xdp;
+       skel->bss->tcp_skc = tcp_skc;
+       skel->bss->lookup_status = -1;
+
+       if (sotype == SOCK_STREAM)
+               connect(fd, (void *)&addr, sizeof(struct sockaddr_in));
+       else
+               sendto(fd, msg, sizeof(msg), 0, (void *)&addr,
+                      sizeof(struct sockaddr_in));
+
+       if (!ASSERT_EQ(skel->bss->lookup_status, lookup_status_exp,
+                      "lookup_status"))
+               goto fail;
+
+       goto close;
+
+fail:
+       ret = -1;
+close:
+       close(fd);
+       return ret;
+}
+
+static void _test_vrf_socket_lookup(struct vrf_socket_lookup *skel, int sotype,
+                                   bool test_xdp, bool tcp_skc)
+{
+       int in_vrf_server = -1, non_vrf_server = -1;
+       struct nstoken *nstoken = NULL;
+
+       nstoken = open_netns(NS0);
+       if (!ASSERT_OK_PTR(nstoken, "setns " NS0))
+               goto done;
+
+       /* Open sockets in and outside VRF */
+       non_vrf_server = make_server(sotype, "0.0.0.0", NON_VRF_PORT, NULL);
+       if (!ASSERT_GE(non_vrf_server, 0, "make_server__outside_vrf_fd"))
+               goto done;
+
+       in_vrf_server = make_server(sotype, "0.0.0.0", IN_VRF_PORT, "veth02");
+       if (!ASSERT_GE(in_vrf_server, 0, "make_server__in_vrf_fd"))
+               goto done;
+
+       /* Perform test from NS1 */
+       close_netns(nstoken);
+       nstoken = open_netns(NS1);
+       if (!ASSERT_OK_PTR(nstoken, "setns " NS1))
+               goto done;
+
+       if (!ASSERT_OK(test_lookup(skel, sotype, IP4_ADDR_VETH02, NON_VRF_PORT,
+                                  test_xdp, tcp_skc, 0), "in_to_out"))
+               goto done;
+       if (!ASSERT_OK(test_lookup(skel, sotype, IP4_ADDR_VETH02, IN_VRF_PORT,
+                                  test_xdp, tcp_skc, 1), "in_to_in"))
+               goto done;
+       if (!ASSERT_OK(test_lookup(skel, sotype, IP4_ADDR_VETH01, NON_VRF_PORT,
+                                  test_xdp, tcp_skc, 1), "out_to_out"))
+               goto done;
+       if (!ASSERT_OK(test_lookup(skel, sotype, IP4_ADDR_VETH01, IN_VRF_PORT,
+                                  test_xdp, tcp_skc, 0), "out_to_in"))
+               goto done;
+
+done:
+       if (non_vrf_server >= 0)
+               close(non_vrf_server);
+       if (in_vrf_server >= 0)
+               close(in_vrf_server);
+       if (nstoken)
+               close_netns(nstoken);
+}
+
+void test_vrf_socket_lookup(void)
+{
+       struct vrf_socket_lookup *skel;
+
+       cleanup();
+
+       skel = vrf_socket_lookup__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "vrf_socket_lookup__open_and_load"))
+               return;
+
+       if (!ASSERT_OK(setup(skel), "setup"))
+               goto done;
+
+       if (test__start_subtest("tc_socket_lookup_tcp"))
+               _test_vrf_socket_lookup(skel, SOCK_STREAM, false, false);
+       if (test__start_subtest("tc_socket_lookup_tcp_skc"))
+               _test_vrf_socket_lookup(skel, SOCK_STREAM, false, false);
+       if (test__start_subtest("tc_socket_lookup_udp"))
+               _test_vrf_socket_lookup(skel, SOCK_STREAM, false, false);
+       if (test__start_subtest("xdp_socket_lookup_tcp"))
+               _test_vrf_socket_lookup(skel, SOCK_STREAM, true, false);
+       if (test__start_subtest("xdp_socket_lookup_tcp_skc"))
+               _test_vrf_socket_lookup(skel, SOCK_STREAM, true, false);
+       if (test__start_subtest("xdp_socket_lookup_udp"))
+               _test_vrf_socket_lookup(skel, SOCK_STREAM, true, false);
+
+done:
+       vrf_socket_lookup__destroy(skel);
+       cleanup();
+}

diff --git a/tools/testing/selftests/bpf/progs/vrf_socket_lookup.c b/tools/testing/selftests/bpf/progs/vrf_socket_lookup.c
new file mode 100644 (file)
index 0000000..26e07a2
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/vrf_socket_lookup.c
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <linux/ip.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/pkt_cls.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+#include <stdbool.h>
+
+int lookup_status;
+bool test_xdp;
+bool tcp_skc;
+
+#define CUR_NS BPF_F_CURRENT_NETNS
+
+static void socket_lookup(void *ctx, void *data_end, void *data)
+{
+       struct ethhdr *eth = data;
+       struct bpf_sock_tuple *tp;
+       struct bpf_sock *sk;
+       struct iphdr *iph;
+       int tplen;
+
+       if (eth + 1 > data_end)
+               return;
+
+       if (eth->h_proto != bpf_htons(ETH_P_IP))
+               return;
+
+       iph = (struct iphdr *)(eth + 1);
+       if (iph + 1 > data_end)
+               return;
+
+       tp = (struct bpf_sock_tuple *)&iph->saddr;
+       tplen = sizeof(tp->ipv4);
+       if ((void *)tp + tplen > data_end)
+               return;
+
+       switch (iph->protocol) {
+       case IPPROTO_TCP:
+               if (tcp_skc)
+                       sk = bpf_skc_lookup_tcp(ctx, tp, tplen, CUR_NS, 0);
+               else
+                       sk = bpf_sk_lookup_tcp(ctx, tp, tplen, CUR_NS, 0);
+               break;
+       case IPPROTO_UDP:
+               sk = bpf_sk_lookup_udp(ctx, tp, tplen, CUR_NS, 0);
+               break;
+       default:
+               return;
+       }
+
+       lookup_status = 0;
+
+       if (sk) {
+               bpf_sk_release(sk);
+               lookup_status = 1;
+       }
+}
+
+SEC("tc")
+int tc_socket_lookup(struct __sk_buff *skb)
+{
+       void *data_end = (void *)(long)skb->data_end;
+       void *data = (void *)(long)skb->data;
+
+       if (test_xdp)
+               return TC_ACT_UNSPEC;
+
+       socket_lookup(skb, data_end, data);
+       return TC_ACT_UNSPEC;
+}
+
+SEC("xdp")
+int xdp_socket_lookup(struct xdp_md *xdp)
+{
+       void *data_end = (void *)(long)xdp->data_end;
+       void *data = (void *)(long)xdp->data;
+
+       if (!test_xdp)
+               return XDP_PASS;
+
+       socket_lookup(xdp, data_end, data);
+       return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";