Commit 95348e46 authored by Daniel Borkmann's avatar Daniel Borkmann Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add netkit test for pkt_type 



Add a test case to assert that the skb->pkt_type which was set from the BPF
program is retained from the netkit xmit side to the peer's device at tcx
ingress location.

  # ./vmtest.sh -- ./test_progs -t netkit
  [...]
  ./test_progs -t netkit
  [    1.140780] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.141127] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  [    1.284601] tsc: Refined TSC clocksource calibration: 3408.006 MHz
  [    1.286672] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x311fd9b189d, max_idle_ns: 440795225691 ns
  [    1.290384] clocksource: Switched to clocksource tsc
  #345     tc_netkit_basic:OK
  #346     tc_netkit_device:OK
  #347     tc_netkit_multi_links:OK
  #348     tc_netkit_multi_opts:OK
  #349     tc_netkit_neigh_links:OK
  #350     tc_netkit_pkt_type:OK
  Summary: 6/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20240524163619.26001-4-daniel@iogearbox.net


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 998ffeb2

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

+84 −0
Original line number Diff line number Diff line
@@ -99,6 +99,16 @@ static int create_netkit(int mode, int policy, int peer_policy, int *ifindex, 
	return err;

}



static void move_netkit(void)

{

	ASSERT_OK(system("ip link set " netkit_peer " netns foo"),

			 "move peer");

	ASSERT_OK(system("ip netns exec foo ip link set dev "

			 netkit_peer " up"), "up peer");

	ASSERT_OK(system("ip netns exec foo ip addr add dev "

			 netkit_peer " 10.0.0.2/24"), "addr peer");

}



static void destroy_netkit(void)

{

	ASSERT_OK(system("ip link del dev " netkit_name), "del primary");
@@ -695,3 +705,77 @@ void serial_test_tc_netkit_neigh_links(void) 
	serial_test_tc_netkit_neigh_links_target(NETKIT_L2, BPF_NETKIT_PRIMARY);

	serial_test_tc_netkit_neigh_links_target(NETKIT_L3, BPF_NETKIT_PRIMARY);

}



static void serial_test_tc_netkit_pkt_type_mode(int mode)

{

	LIBBPF_OPTS(bpf_netkit_opts, optl_nk);

	LIBBPF_OPTS(bpf_tcx_opts, optl_tcx);

	int err, ifindex, ifindex2;

	struct test_tc_link *skel;

	struct bpf_link *link;



	err = create_netkit(mode, NETKIT_PASS, NETKIT_PASS,

			    &ifindex, true);

	if (err)

		return;



	ifindex2 = if_nametoindex(netkit_peer);

	ASSERT_NEQ(ifindex, ifindex2, "ifindex_1_2");



	skel = test_tc_link__open();

	if (!ASSERT_OK_PTR(skel, "skel_open"))

		goto cleanup;



	ASSERT_EQ(bpf_program__set_expected_attach_type(skel->progs.tc1,

		  BPF_NETKIT_PRIMARY), 0, "tc1_attach_type");

	ASSERT_EQ(bpf_program__set_expected_attach_type(skel->progs.tc7,

		  BPF_TCX_INGRESS), 0, "tc7_attach_type");



	err = test_tc_link__load(skel);

	if (!ASSERT_OK(err, "skel_load"))

		goto cleanup;



	assert_mprog_count_ifindex(ifindex,  BPF_NETKIT_PRIMARY, 0);

	assert_mprog_count_ifindex(ifindex2, BPF_TCX_INGRESS, 0);



	link = bpf_program__attach_netkit(skel->progs.tc1, ifindex, &optl_nk);

	if (!ASSERT_OK_PTR(link, "link_attach"))

		goto cleanup;



	skel->links.tc1 = link;



	assert_mprog_count_ifindex(ifindex,  BPF_NETKIT_PRIMARY, 1);

	assert_mprog_count_ifindex(ifindex2, BPF_TCX_INGRESS, 0);



	link = bpf_program__attach_tcx(skel->progs.tc7, ifindex2, &optl_tcx);

	if (!ASSERT_OK_PTR(link, "link_attach"))

		goto cleanup;



	skel->links.tc7 = link;



	assert_mprog_count_ifindex(ifindex,  BPF_NETKIT_PRIMARY, 1);

	assert_mprog_count_ifindex(ifindex2, BPF_TCX_INGRESS, 1);



	move_netkit();



	tc_skel_reset_all_seen(skel);

	skel->bss->set_type = true;

	ASSERT_EQ(send_icmp(), 0, "icmp_pkt");



	ASSERT_EQ(skel->bss->seen_tc1, true, "seen_tc1");

	ASSERT_EQ(skel->bss->seen_tc7, true, "seen_tc7");



	ASSERT_EQ(skel->bss->seen_host,  true, "seen_host");

	ASSERT_EQ(skel->bss->seen_mcast, true, "seen_mcast");

cleanup:

	test_tc_link__destroy(skel);



	assert_mprog_count_ifindex(ifindex,  BPF_NETKIT_PRIMARY, 0);

	destroy_netkit();

}



void serial_test_tc_netkit_pkt_type(void)

{

	serial_test_tc_netkit_pkt_type_mode(NETKIT_L2);

	serial_test_tc_netkit_pkt_type_mode(NETKIT_L3);

}

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

+34 −1
Original line number Diff line number Diff line
@@ -4,7 +4,8 @@ 


#include <linux/bpf.h>

#include <linux/if_ether.h>



#include <linux/stddef.h>

#include <linux/if_packet.h>

#include <bpf/bpf_endian.h>

#include <bpf/bpf_helpers.h>
@@ -16,7 +17,13 @@ bool seen_tc3; 
bool seen_tc4;

bool seen_tc5;

bool seen_tc6;

bool seen_tc7;



bool set_type;



bool seen_eth;

bool seen_host;

bool seen_mcast;



SEC("tc/ingress")

int tc1(struct __sk_buff *skb)
@@ -28,8 +35,16 @@ int tc1(struct __sk_buff *skb) 
	if (bpf_skb_load_bytes(skb, 0, &eth, sizeof(eth)))

		goto out;

	seen_eth = eth.h_proto == bpf_htons(ETH_P_IP);

	seen_host = skb->pkt_type == PACKET_HOST;

	if (seen_host && set_type) {

		eth.h_dest[0] = 4;

		if (bpf_skb_store_bytes(skb, 0, &eth, sizeof(eth), 0))

			goto fail;

		bpf_skb_change_type(skb, PACKET_MULTICAST);

	}

out:

	seen_tc1 = true;

fail:

	return TCX_NEXT;

}
@@ -67,3 +82,21 @@ int tc6(struct __sk_buff *skb) 
	seen_tc6 = true;

	return TCX_PASS;

}



SEC("tc/ingress")

int tc7(struct __sk_buff *skb)

{

	struct ethhdr eth = {};



	if (skb->protocol != __bpf_constant_htons(ETH_P_IP))

		goto out;

	if (bpf_skb_load_bytes(skb, 0, &eth, sizeof(eth)))

		goto out;

	if (eth.h_dest[0] == 4 && set_type) {

		seen_mcast = skb->pkt_type == PACKET_MULTICAST;

		bpf_skb_change_type(skb, PACKET_HOST);

	}

out:

	seen_tc7 = true;

	return TCX_PASS;

}