Merge branch 'selftests-bpf-migrate-test_xdp_vlan-sh-into-test_progs'

Bastien Curutchet says:

====================
selftests/bpf: Migrate test_xdp_vlan.sh into test_progs

Hi all,

This patch series continues the work to migrate the script tests into
prog_tests.

test_xdp_vlan.sh tests the ability of an XDP program to modify the VLAN
ids on the fly. This isn't currently covered by an other test in the
test_progs framework so I add a new file prog_tests/xdp_vlan.c that does
the exact same tests (same network topology, same BPF programs) and
remove the script.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Martin KaFai Lau <[email protected]>

Author: Martin KaFai Lau

tools/testing/selftests/bpf/Makefile

@@ -101,8 +101,6 @@ TEST_FILES = xsk_prereqs.sh $(wildcard progs/btf_dump_test_case_*.c)
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \
 	test_lirc_mode2.sh \
-	test_xdp_vlan_mode_generic.sh \
-	test_xdp_vlan_mode_native.sh \
 	test_tc_tunnel.sh \
 	test_tc_edt.sh \
 	test_xdping.sh \
@@ -115,7 +113,7 @@ TEST_PROGS := test_kmod.sh \
 
 TEST_PROGS_EXTENDED := \
 	ima_setup.sh verify_sig_setup.sh \
-	test_xdp_vlan.sh test_bpftool.py
+	test_bpftool.py
 
 TEST_KMODS := bpf_testmod.ko bpf_test_no_cfi.ko bpf_test_modorder_x.ko \
 	bpf_test_modorder_y.ko

tools/testing/selftests/bpf/prog_tests/xdp_vlan.c

@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Network topology:
+ *  -----------        -----------
+ *  |  NS1    |        |   NS2   |
+ *  | veth0  -|--------|- veth0  |
+ *  -----------        -----------
+ *
+ */
+
+#define _GNU_SOURCE
+#include <net/if.h>
+#include <uapi/linux/if_link.h>
+
+#include "network_helpers.h"
+#include "test_progs.h"
+#include "test_xdp_vlan.skel.h"
+
+
+#define VETH_NAME	"veth0"
+#define NS_MAX_SIZE	32
+#define NS1_NAME	"ns-xdp-vlan-1-"
+#define NS2_NAME	"ns-xdp-vlan-2-"
+#define NS1_IP_ADDR	"100.64.10.1"
+#define NS2_IP_ADDR	"100.64.10.2"
+#define VLAN_ID		4011
+
+static int setup_network(char *ns1, char *ns2)
+{
+	if (!ASSERT_OK(append_tid(ns1, NS_MAX_SIZE), "create ns1 name"))
+		goto fail;
+	if (!ASSERT_OK(append_tid(ns2, NS_MAX_SIZE), "create ns2 name"))
+		goto fail;
+
+	SYS(fail, "ip netns add %s", ns1);
+	SYS(fail, "ip netns add %s", ns2);
+	SYS(fail, "ip -n %s link add %s type veth peer name %s netns %s",
+	    ns1, VETH_NAME, VETH_NAME, ns2);
+
+	/* NOTICE: XDP require VLAN header inside packet payload
+	 *  - Thus, disable VLAN offloading driver features
+	 */
+	SYS(fail, "ip netns exec %s ethtool -K %s rxvlan off txvlan off", ns1, VETH_NAME);
+	SYS(fail, "ip netns exec %s ethtool -K %s rxvlan off txvlan off", ns2, VETH_NAME);
+
+	/* NS1 configuration */
+	SYS(fail, "ip -n %s addr add %s/24 dev %s", ns1, NS1_IP_ADDR, VETH_NAME);
+	SYS(fail, "ip -n %s link set %s up", ns1, VETH_NAME);
+
+	/* NS2 configuration */
+	SYS(fail, "ip -n %s link add link %s name %s.%d type vlan id %d",
+	    ns2, VETH_NAME, VETH_NAME, VLAN_ID, VLAN_ID);
+	SYS(fail, "ip -n %s addr add %s/24 dev %s.%d", ns2, NS2_IP_ADDR, VETH_NAME, VLAN_ID);
+	SYS(fail, "ip -n %s link set %s up", ns2, VETH_NAME);
+	SYS(fail, "ip -n %s link set %s.%d up", ns2, VETH_NAME, VLAN_ID);
+
+	/* At this point ping should fail because VLAN tags are only used by NS2 */
+	return !SYS_NOFAIL("ip netns exec %s ping -W 1 -c1 %s", ns2, NS1_IP_ADDR);
+
+fail:
+	return -1;
+}
+
+static void cleanup_network(const char *ns1, const char *ns2)
+{
+	SYS_NOFAIL("ip netns del %s", ns1);
+	SYS_NOFAIL("ip netns del %s", ns2);
+}
+
+static void xdp_vlan(struct bpf_program *xdp, struct bpf_program *tc, u32 flags)
+{
+	LIBBPF_OPTS(bpf_tc_hook, tc_hook, .attach_point = BPF_TC_EGRESS);
+	LIBBPF_OPTS(bpf_tc_opts, tc_opts, .handle = 1, .priority = 1);
+	char ns1[NS_MAX_SIZE] = NS1_NAME;
+	char ns2[NS_MAX_SIZE] = NS2_NAME;
+	struct nstoken *nstoken = NULL;
+	int interface;
+	int ret;
+
+	if (!ASSERT_OK(setup_network(ns1, ns2), "setup network"))
+		goto cleanup;
+
+	nstoken = open_netns(ns1);
+	if (!ASSERT_OK_PTR(nstoken, "open NS1"))
+		goto cleanup;
+
+	interface = if_nametoindex(VETH_NAME);
+	if (!ASSERT_NEQ(interface, 0, "get interface index"))
+		goto cleanup;
+
+	ret = bpf_xdp_attach(interface, bpf_program__fd(xdp), flags, NULL);
+	if (!ASSERT_OK(ret, "attach xdp_vlan_change"))
+		goto cleanup;
+
+	tc_hook.ifindex = interface;
+	ret = bpf_tc_hook_create(&tc_hook);
+	if (!ASSERT_OK(ret, "bpf_tc_hook_create"))
+		goto detach_xdp;
+
+	/* Now we'll use BPF programs to pop/push the VLAN tags */
+	tc_opts.prog_fd = bpf_program__fd(tc);
+	ret = bpf_tc_attach(&tc_hook, &tc_opts);
+	if (!ASSERT_OK(ret, "bpf_tc_attach"))
+		goto detach_xdp;
+
+	close_netns(nstoken);
+	nstoken = NULL;
+
+	/* Now the namespaces can reach each-other, test with pings */
+	SYS(detach_tc, "ip netns exec %s ping -i 0.2 -W 2 -c 2 %s > /dev/null", ns1, NS2_IP_ADDR);
+	SYS(detach_tc, "ip netns exec %s ping -i 0.2 -W 2 -c 2 %s > /dev/null", ns2, NS1_IP_ADDR);
+
+
+detach_tc:
+	bpf_tc_detach(&tc_hook, &tc_opts);
+detach_xdp:
+	bpf_xdp_detach(interface, flags, NULL);
+cleanup:
+	close_netns(nstoken);
+	cleanup_network(ns1, ns2);
+}
+
+/* First test: Remove VLAN by setting VLAN ID 0, using "xdp_vlan_change"
+ * egress use TC to add back VLAN tag 4011
+ */
+void test_xdp_vlan_change(void)
+{
+	struct test_xdp_vlan *skel;
+
+	skel = test_xdp_vlan__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "xdp_vlan__open_and_load"))
+		return;
+
+	if (test__start_subtest("0"))
+		xdp_vlan(skel->progs.xdp_vlan_change, skel->progs.tc_vlan_push, 0);
+
+	if (test__start_subtest("DRV_MODE"))
+		xdp_vlan(skel->progs.xdp_vlan_change, skel->progs.tc_vlan_push,
+			 XDP_FLAGS_DRV_MODE);
+
+	if (test__start_subtest("SKB_MODE"))
+		xdp_vlan(skel->progs.xdp_vlan_change, skel->progs.tc_vlan_push,
+			 XDP_FLAGS_SKB_MODE);
+
+	test_xdp_vlan__destroy(skel);
+}
+
+/* Second test: XDP prog fully remove vlan header
+ *
+ * Catch kernel bug for generic-XDP, that doesn't allow us to
+ * remove a VLAN header, because skb->protocol still contain VLAN
+ * ETH_P_8021Q indication, and this cause overwriting of our changes.
+ */
+void test_xdp_vlan_remove(void)
+{
+	struct test_xdp_vlan *skel;
+
+	skel = test_xdp_vlan__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "xdp_vlan__open_and_load"))
+		return;
+
+	if (test__start_subtest("0"))
+		xdp_vlan(skel->progs.xdp_vlan_remove_outer2, skel->progs.tc_vlan_push, 0);
+
+	if (test__start_subtest("DRV_MODE"))
+		xdp_vlan(skel->progs.xdp_vlan_remove_outer2, skel->progs.tc_vlan_push,
+			 XDP_FLAGS_DRV_MODE);
+
+	if (test__start_subtest("SKB_MODE"))
+		xdp_vlan(skel->progs.xdp_vlan_remove_outer2, skel->progs.tc_vlan_push,
+			 XDP_FLAGS_SKB_MODE);
+
+	test_xdp_vlan__destroy(skel);
+}

tools/testing/selftests/bpf/progs/test_xdp_vlan.c

@@ -102,8 +102,8 @@ bool parse_eth_frame(struct ethhdr *eth, void *data_end, struct parse_pkt *pkt)
 #define TESTVLAN 4011 /* 0xFAB */
 // #define TO_VLAN  4000 /* 0xFA0 (hint 0xOA0 = 160) */
 
-SEC("xdp_drop_vlan_4011")
-int  xdp_prognum0(struct xdp_md *ctx)
+SEC("xdp")
+int xdp_drop_vlan_4011(struct xdp_md *ctx)
 {
 	void *data_end = (void *)(long)ctx->data_end;
 	void *data     = (void *)(long)ctx->data;
@@ -144,8 +144,8 @@ Load prog with ip tool:
 /* Changing VLAN to zero, have same practical effect as removing the VLAN. */
 #define TO_VLAN	0
 
-SEC("xdp_vlan_change")
-int  xdp_prognum1(struct xdp_md *ctx)
+SEC("xdp")
+int xdp_vlan_change(struct xdp_md *ctx)
 {
 	void *data_end = (void *)(long)ctx->data_end;
 	void *data     = (void *)(long)ctx->data;
@@ -178,8 +178,8 @@ int  xdp_prognum1(struct xdp_md *ctx)
 #endif
 #define VLAN_HDR_SZ	4	/* bytes */
 
-SEC("xdp_vlan_remove_outer")
-int  xdp_prognum2(struct xdp_md *ctx)
+SEC("xdp")
+int xdp_vlan_remove_outer(struct xdp_md *ctx)
 {
 	void *data_end = (void *)(long)ctx->data_end;
 	void *data     = (void *)(long)ctx->data;
@@ -224,8 +224,8 @@ void shift_mac_4bytes_32bit(void *data)
 	p[1] = p[0];
 }
 
-SEC("xdp_vlan_remove_outer2")
-int  xdp_prognum3(struct xdp_md *ctx)
+SEC("xdp")
+int xdp_vlan_remove_outer2(struct xdp_md *ctx)
 {
 	void *data_end = (void *)(long)ctx->data_end;
 	void *data     = (void *)(long)ctx->data;
@@ -254,8 +254,8 @@ int  xdp_prognum3(struct xdp_md *ctx)
  * The TC-clsact eBPF programs (currently) need to be attach via TC commands
  */
 
-SEC("tc_vlan_push")
-int _tc_progA(struct __sk_buff *ctx)
+SEC("tc")
+int tc_vlan_push(struct __sk_buff *ctx)
 {
 	bpf_skb_vlan_push(ctx, bpf_htons(ETH_P_8021Q), TESTVLAN);