[v12,bpf-next,4/4] selftests/bpf: add xdp_redirect_multi test

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 525e4b3fb514..f405b20c1e6c 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -54,6 +54,7 @@  TEST_FILES = xsk_prereqs.sh \
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \
 	test_xdp_redirect.sh \
+	test_xdp_redirect_multi.sh \
 	test_xdp_meta.sh \
 	test_xdp_veth.sh \
 	test_offload.py \
@@ -84,7 +85,7 @@  TEST_PROGS_EXTENDED := with_addr.sh \
 TEST_GEN_PROGS_EXTENDED = test_sock_addr test_skb_cgroup_id_user \
 	flow_dissector_load test_flow_dissector test_tcp_check_syncookie_user \
 	test_lirc_mode2_user xdping test_cpp runqslower bench bpf_testmod.ko \
-	xdpxceiver
+	xdpxceiver xdp_redirect_multi
 
 TEST_CUSTOM_PROGS = $(OUTPUT)/urandom_read
 
diff --git a/tools/testing/selftests/bpf/progs/xdp_redirect_multi_kern.c b/tools/testing/selftests/bpf/progs/xdp_redirect_multi_kern.c
new file mode 100644
index 000000000000..880debcbcd65
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/xdp_redirect_multi_kern.c
@@ -0,0 +1,94 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#define KBUILD_MODNAME "foo"
+#include <string.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+/* One map use devmap, another one use devmap_hash for testing */
+struct {
+	__uint(type, BPF_MAP_TYPE_DEVMAP);
+	__uint(key_size, sizeof(int));
+	__uint(value_size, sizeof(int));
+	__uint(max_entries, 1024);
+} map_all SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_DEVMAP_HASH);
+	__uint(key_size, sizeof(int));
+	__uint(value_size, sizeof(struct bpf_devmap_val));
+	__uint(max_entries, 128);
+} map_egress SEC(".maps");
+
+/* map to store egress interfaces mac addresses */
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__type(key, __u32);
+	__type(value, __be64);
+	__uint(max_entries, 128);
+} mac_map SEC(".maps");
+
+SEC("xdp_redirect_map_multi")
+int xdp_redirect_map_multi_prog(struct xdp_md *ctx)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data = (void *)(long)ctx->data;
+	int if_index = ctx->ingress_ifindex;
+	struct ethhdr *eth = data;
+	__u16 h_proto;
+	__u64 nh_off;
+
+	nh_off = sizeof(*eth);
+	if (data + nh_off > data_end)
+		return XDP_DROP;
+
+	h_proto = eth->h_proto;
+
+	/* Using IPv4 for (BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS) testing */
+	if (h_proto == bpf_htons(ETH_P_IP))
+		return bpf_redirect_map(&map_all, 0,
+					BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS);
+	/* Using IPv6 for none flag testing */
+	else if (h_proto == bpf_htons(ETH_P_IPV6))
+		return bpf_redirect_map(&map_all, if_index, 0);
+	/* All others for BPF_F_BROADCAST testing */
+	else
+		return bpf_redirect_map(&map_all, 0, BPF_F_BROADCAST);
+}
+
+/* The following 2 progs are for 2nd devmap prog testing */
+SEC("xdp_redirect_map_ingress")
+int xdp_redirect_map_all_prog(struct xdp_md *ctx)
+{
+	return bpf_redirect_map(&map_egress, 0,
+				BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS);
+}
+
+SEC("xdp_devmap/map_prog")
+int xdp_devmap_prog(struct xdp_md *ctx)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data = (void *)(long)ctx->data;
+	__u32 key = ctx->egress_ifindex;
+	struct ethhdr *eth = data;
+	__u64 nh_off;
+	__be64 *mac;
+
+	nh_off = sizeof(*eth);
+	if (data + nh_off > data_end)
+		return XDP_DROP;
+
+	mac = bpf_map_lookup_elem(&mac_map, &key);
+	if (mac)
+		__builtin_memcpy(eth->h_source, mac, ETH_ALEN);
+
+	return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_xdp_redirect_multi.sh b/tools/testing/selftests/bpf/test_xdp_redirect_multi.sh
new file mode 100755
index 000000000000..1538373157e3
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_xdp_redirect_multi.sh
@@ -0,0 +1,204 @@ 
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test topology:
+#     - - - - - - - - - - - - - - - - - - - - - - - - -
+#    | veth1         veth2         veth3 |  ... init net
+#     - -| - - - - - - | - - - - - - | - -
+#    ---------     ---------     ---------
+#    | veth0 |     | veth0 |     | veth0 |  ...
+#    ---------     ---------     ---------
+#       ns1           ns2           ns3
+#
+# Test modules:
+# XDP modes: generic, native, native + egress_prog
+#
+# Test cases:
+#   ARP: Testing BPF_F_BROADCAST, the ingress interface also should receive
+#   the redirects.
+#      ns1 -> gw: ns1, ns2, ns3, should receive the arp request
+#   IPv4: Testing BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS, the ingress
+#   interface should not receive the redirects.
+#      ns1 -> gw: ns1 should not receive, ns2, ns3 should receive redirects.
+#   IPv6: Testing none flag, all the pkts should be redirected back
+#      ping test: ns1 -> ns2 (block), echo requests will be redirect back
+#   egress_prog:
+#      all src mac should be egress interface's mac
+
+# netns numbers
+NUM=3
+IFACES=""
+DRV_MODE="xdpgeneric xdpdrv xdpegress"
+PASS=0
+FAIL=0
+
+test_pass()
+{
+	echo "Pass: $@"
+	PASS=$((PASS + 1))
+}
+
+test_fail()
+{
+	echo "fail: $@"
+	FAIL=$((FAIL + 1))
+}
+
+clean_up()
+{
+	for i in $(seq $NUM); do
+		ip link del veth$i 2> /dev/null
+		ip netns del ns$i 2> /dev/null
+	done
+}
+
+# Kselftest framework requirement - SKIP code is 4.
+check_env()
+{
+	ip link set dev lo xdpgeneric off &>/dev/null
+	if [ $? -ne 0 ];then
+		echo "selftests: [SKIP] Could not run test without the ip xdpgeneric support"
+		exit 4
+	fi
+
+	which tcpdump &>/dev/null
+	if [ $? -ne 0 ];then
+		echo "selftests: [SKIP] Could not run test without tcpdump"
+		exit 4
+	fi
+}
+
+setup_ns()
+{
+	local mode=$1
+	IFACES=""
+
+	if [ "$mode" = "xdpegress" ]; then
+		mode="xdpdrv"
+	fi
+
+	for i in $(seq $NUM); do
+	        ip netns add ns$i
+	        ip link add veth$i type veth peer name veth0 netns ns$i
+		ip link set veth$i up
+		ip -n ns$i link set veth0 up
+
+		ip -n ns$i addr add 192.0.2.$i/24 dev veth0
+		ip -n ns$i addr add 2001:db8::$i/64 dev veth0
+		# Add a neigh entry for IPv4 ping test
+		ip -n ns$i neigh add 192.0.2.253 lladdr 00:00:00:00:00:01 dev veth0
+		ip -n ns$i link set veth0 $mode obj \
+			xdp_dummy.o sec xdp_dummy &> /dev/null || \
+			{ test_fail "Unable to load dummy xdp" && exit 1; }
+		IFACES="$IFACES veth$i"
+		veth_mac[$i]=$(ip link show veth$i | awk '/link\/ether/ {print $2}')
+	done
+}
+
+do_egress_tests()
+{
+	local mode=$1
+
+	# mac test
+	ip netns exec ns2 tcpdump -e -i veth0 -nn -l -e &> mac_ns1-2_${mode}.log &
+	ip netns exec ns3 tcpdump -e -i veth0 -nn -l -e &> mac_ns1-3_${mode}.log &
+	sleep 0.5
+	ip netns exec ns1 ping 192.0.2.254 -i 0.1 -c 4 &> /dev/null
+	sleep 0.5
+	pkill -9 tcpdump
+
+	# mac check
+	grep -q "${veth_mac[2]} > ff:ff:ff:ff:ff:ff" mac_ns1-2_${mode}.log && \
+	       test_pass "$mode mac ns1-2" || test_fail "$mode mac ns1-2"
+	grep -q "${veth_mac[3]} > ff:ff:ff:ff:ff:ff" mac_ns1-3_${mode}.log && \
+		test_pass "$mode mac ns1-3" || test_fail "$mode mac ns1-3"
+}
+
+do_ping_tests()
+{
+	local mode=$1
+
+	# ping6 test: echo request should be redirect back to itself, not others
+	ip netns exec ns1 ip neigh add 2001:db8::2 dev veth0 lladdr 00:00:00:00:00:02
+
+	ip netns exec ns1 tcpdump -i veth0 -nn -l -e &> ns1-1_${mode}.log &
+	ip netns exec ns2 tcpdump -i veth0 -nn -l -e &> ns1-2_${mode}.log &
+	ip netns exec ns3 tcpdump -i veth0 -nn -l -e &> ns1-3_${mode}.log &
+	sleep 0.5
+	# ARP test
+	ip netns exec ns1 ping 192.0.2.254 -i 0.1 -c 4 &> /dev/null
+	# IPv4 test
+	ip netns exec ns1 ping 192.0.2.253 -i 0.1 -c 4 &> /dev/null
+	# IPv6 test
+	ip netns exec ns1 ping6 2001:db8::2 -i 0.1 -c 2 &> /dev/null
+	sleep 0.5
+	pkill -9 tcpdump
+
+	# All netns should receive the redirect arp requests
+	[ $(grep -c "who-has 192.0.2.254" ns1-1_${mode}.log) -gt 4 ] && \
+		test_pass "$mode arp(F_BROADCAST) ns1-1" || \
+		test_fail "$mode arp(F_BROADCAST) ns1-1"
+	[ $(grep -c "who-has 192.0.2.254" ns1-2_${mode}.log) -le 4 ] && \
+		test_pass "$mode arp(F_BROADCAST) ns1-2" || \
+		test_fail "$mode arp(F_BROADCAST) ns1-2"
+	[ $(grep -c "who-has 192.0.2.254" ns1-3_${mode}.log) -le 4 ] && \
+		test_pass "$mode arp(F_BROADCAST) ns1-3" || \
+		test_fail "$mode arp(F_BROADCAST) ns1-3"
+
+	# ns1 should not receive the redirect echo request, others should
+	[ $(grep -c "ICMP echo request" ns1-1_${mode}.log) -eq 4 ] && \
+		test_pass "$mode IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-1" || \
+		test_fail "$mode IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-1"
+	[ $(grep -c "ICMP echo request" ns1-2_${mode}.log) -eq 4 ] && \
+		test_pass "$mode IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-2" || \
+		test_fail "$mode IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-2"
+	[ $(grep -c "ICMP echo request" ns1-3_${mode}.log) -eq 4 ] && \
+		test_pass "$mode IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-3" || \
+		test_fail "$mode IPv4 (F_BROADCAST|F_EXCLUDE_INGRESS) ns1-3"
+
+	# ns1 should receive the echo request, ns2 should not
+	[ $(grep -c "ICMP6, echo request" ns1-1_${mode}.log) -eq 4 ] && \
+		test_pass "$mode IPv6 (no flags) ns1-1" || \
+		test_fail "$mode IPv6 (no flags) ns1-1"
+	[ $(grep -c "ICMP6, echo request" ns1-2_${mode}.log) -eq 0 ] && \
+		test_pass "$mode IPv6 (no flags) ns1-2" || \
+		test_fail "$mode IPv6 (no flags) ns1-2"
+}
+
+do_tests()
+{
+	local mode=$1
+	local drv_p
+
+	case ${mode} in
+		xdpdrv)  drv_p="-N";;
+		xdpegress) drv_p="-X";;
+		xdpgeneric) drv_p="-S";;
+	esac
+
+	./xdp_redirect_multi $drv_p $IFACES &> xdp_redirect_${mode}.log &
+	xdp_pid=$!
+	sleep 1
+
+	if [ "$mode" = "xdpegress" ]; then
+		do_egress_tests $mode
+	else
+		do_ping_tests $mode
+	fi
+
+	kill $xdp_pid
+}
+
+trap clean_up 0 2 3 6 9
+
+check_env
+rm -f xdp_redirect_*.log ns*.log mac_ns*.log
+
+for mode in ${DRV_MODE}; do
+	setup_ns $mode
+	do_tests $mode
+	clean_up
+done
+
+echo "Summary: PASS $PASS, FAIL $FAIL"
+[ $FAIL -eq 0 ] && exit 0 || exit 1
diff --git a/tools/testing/selftests/bpf/xdp_redirect_multi.c b/tools/testing/selftests/bpf/xdp_redirect_multi.c
new file mode 100644
index 000000000000..3696a8f32c23
--- /dev/null
+++ b/tools/testing/selftests/bpf/xdp_redirect_multi.c
@@ -0,0 +1,226 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <linux/if_link.h>
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <net/if.h>
+#include <unistd.h>
+#include <libgen.h>
+#include <sys/resource.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include "bpf_util.h"
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#define MAX_IFACE_NUM 32
+#define MAX_INDEX_NUM 1024
+
+static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+static int ifaces[MAX_IFACE_NUM] = {};
+
+static void int_exit(int sig)
+{
+	__u32 prog_id = 0;
+	int i;
+
+	for (i = 0; ifaces[i] > 0; i++) {
+		if (bpf_get_link_xdp_id(ifaces[i], &prog_id, xdp_flags)) {
+			printf("bpf_get_link_xdp_id failed\n");
+			exit(1);
+		}
+		if (prog_id)
+			bpf_set_link_xdp_fd(ifaces[i], -1, xdp_flags);
+	}
+
+	exit(0);
+}
+
+static int get_mac_addr(unsigned int ifindex, void *mac_addr)
+{
+	char ifname[IF_NAMESIZE];
+	struct ifreq ifr;
+	int fd, ret = -1;
+
+	fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (fd < 0)
+		return ret;
+
+	if (!if_indextoname(ifindex, ifname))
+		goto err_out;
+
+	strcpy(ifr.ifr_name, ifname);
+
+	if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0)
+		goto err_out;
+
+	memcpy(mac_addr, ifr.ifr_hwaddr.sa_data, 6 * sizeof(char));
+	ret = 0;
+
+err_out:
+	close(fd);
+	return ret;
+}
+
+static void usage(const char *prog)
+{
+	fprintf(stderr,
+		"usage: %s [OPTS] <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n"
+		"OPTS:\n"
+		"    -S    use skb-mode\n"
+		"    -N    enforce native mode\n"
+		"    -F    force loading prog\n"
+		"    -X    load xdp program on egress\n",
+		prog);
+}
+
+int main(int argc, char **argv)
+{
+	int prog_fd, group_all, mac_map;
+	struct bpf_program *ingress_prog, *egress_prog;
+	struct bpf_prog_load_attr prog_load_attr = {
+		.prog_type = BPF_PROG_TYPE_UNSPEC,
+	};
+	int i, ret, opt, egress_prog_fd = 0;
+	struct bpf_devmap_val devmap_val;
+	bool attach_egress_prog = false;
+	unsigned char mac_addr[6];
+	char ifname[IF_NAMESIZE];
+	struct bpf_object *obj;
+	unsigned int ifindex;
+	char filename[256];
+
+	while ((opt = getopt(argc, argv, "SNFX")) != -1) {
+		switch (opt) {
+		case 'S':
+			xdp_flags |= XDP_FLAGS_SKB_MODE;
+			break;
+		case 'N':
+			/* default, set below */
+			break;
+		case 'F':
+			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
+			break;
+		case 'X':
+			attach_egress_prog = true;
+			break;
+		default:
+			usage(basename(argv[0]));
+			return 1;
+		}
+	}
+
+	if (!(xdp_flags & XDP_FLAGS_SKB_MODE)) {
+		xdp_flags |= XDP_FLAGS_DRV_MODE;
+	} else if (attach_egress_prog) {
+		printf("Load xdp program on egress with SKB mode not supported yet\n");
+		goto err_out;
+	}
+
+	if (optind == argc) {
+		printf("usage: %s <IFNAME|IFINDEX> <IFNAME|IFINDEX> ...\n", argv[0]);
+		goto err_out;
+	}
+
+	printf("Get interfaces");
+	for (i = 0; i < MAX_IFACE_NUM && argv[optind + i]; i++) {
+		ifaces[i] = if_nametoindex(argv[optind + i]);
+		if (!ifaces[i])
+			ifaces[i] = strtoul(argv[optind + i], NULL, 0);
+		if (!if_indextoname(ifaces[i], ifname)) {
+			perror("Invalid interface name or i");
+			goto err_out;
+		}
+		if (ifaces[i] > MAX_INDEX_NUM) {
+			printf("Interface index to large\n");
+			goto err_out;
+		}
+		printf(" %d", ifaces[i]);
+	}
+	printf("\n");
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	prog_load_attr.file = filename;
+
+	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
+		goto err_out;
+
+	if (attach_egress_prog)
+		group_all = bpf_object__find_map_fd_by_name(obj, "map_egress");
+	else
+		group_all = bpf_object__find_map_fd_by_name(obj, "map_all");
+	mac_map = bpf_object__find_map_fd_by_name(obj, "mac_map");
+
+	if (group_all < 0 || mac_map < 0) {
+		printf("bpf_object__find_map_fd_by_name failed\n");
+		goto err_out;
+	}
+
+	if (attach_egress_prog) {
+		/* Find ingress/egress prog for 2nd xdp prog */
+		ingress_prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_all_prog");
+		egress_prog = bpf_object__find_program_by_name(obj, "xdp_devmap_prog");
+		if (!ingress_prog || !egress_prog) {
+			printf("finding ingress/egress_prog in obj file failed\n");
+			goto err_out;
+		}
+		prog_fd = bpf_program__fd(ingress_prog);
+		egress_prog_fd = bpf_program__fd(egress_prog);
+		if (prog_fd < 0 || egress_prog_fd < 0) {
+			printf("find egress_prog fd failed\n");
+			goto err_out;
+		}
+	}
+
+	signal(SIGINT, int_exit);
+	signal(SIGTERM, int_exit);
+
+	/* Init forward multicast groups and exclude group */
+	for (i = 0; ifaces[i] > 0; i++) {
+		ifindex = ifaces[i];
+
+		if (attach_egress_prog) {
+			ret = get_mac_addr(ifindex, mac_addr);
+			if (ret < 0) {
+				printf("get interface %d mac failed\n", ifindex);
+				goto err_out;
+			}
+			ret = bpf_map_update_elem(mac_map, &ifindex, mac_addr, 0);
+			if (ret) {
+				perror("bpf_update_elem mac_map failed\n");
+				goto err_out;
+			}
+		}
+
+		/* Add all the interfaces to group all */
+		devmap_val.ifindex = ifindex;
+		devmap_val.bpf_prog.fd = egress_prog_fd;
+		ret = bpf_map_update_elem(group_all, &ifindex, &devmap_val, 0);
+		if (ret) {
+			perror("bpf_map_update_elem");
+			goto err_out;
+		}
+
+		/* bind prog_fd to each interface */
+		ret = bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags);
+		if (ret) {
+			printf("Set xdp fd failed on %d\n", ifindex);
+			goto err_out;
+		}
+	}
+
+	/* sleep some time for testing */
+	sleep(999);
+
+	return 0;
+
+err_out:
+	return 1;
+}