selftests/bpf: Rewrite test_tc_redirect.sh as prog_tests/tc_redirect.c

As discussed in [0], this ports test_tc_redirect.sh to the test_progs
framework and removes the old test.

This makes it more in line with rest of the tests and makes it possible
to run this test case with vmtest.sh and under the bpf CI.

The upcoming skb_change_head() helper fix in [0] is depending on it and
extending the test case to redirect a packet from L3 device to veth.

  [0] https://lore.kernel.org/bpf/20210427135550.807355-1-joamaki@gmail.comSigned-off-by: Jussi Maki <joamaki@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210505085925.783985-1-joamaki@gmail.com

tools/testing/selftests/bpf/network_helpers.c

@@ -40,7 +40,7 @@ struct ipv6_packet pkt_v6 = {
 	.tcp.doff = 5,
 };
 
-static int settimeo(int fd, int timeout_ms)
+int settimeo(int fd, int timeout_ms)
 {
 	struct timeval timeout = { .tv_sec = 3 };
 

tools/testing/selftests/bpf/network_helpers.h

@@ -33,6 +33,7 @@ struct ipv6_packet {
 } __packed;
 extern struct ipv6_packet pkt_v6;
 
+int settimeo(int fd, int timeout_ms);
 int start_server(int family, int type, const char *addr, __u16 port,
 		 int timeout_ms);
 int connect_to_fd(int server_fd, int timeout_ms);

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

@@ -33,17 +33,8 @@
 				 a.s6_addr32[3] == b.s6_addr32[3])
 #endif
 
-enum {
-	dev_src,
-	dev_dst,
-};
-
-struct bpf_map_def SEC("maps") ifindex_map = {
-	.type		= BPF_MAP_TYPE_ARRAY,
-	.key_size	= sizeof(int),
-	.value_size	= sizeof(int),
-	.max_entries	= 2,
-};
+static volatile const __u32 IFINDEX_SRC;
+static volatile const __u32 IFINDEX_DST;
 
 static __always_inline bool is_remote_ep_v4(struct __sk_buff *skb,
 					    __be32 addr)
@@ -79,14 +70,8 @@ static __always_inline bool is_remote_ep_v6(struct __sk_buff *skb,
 	return v6_equal(ip6h->daddr, addr);
 }
 
-static __always_inline int get_dev_ifindex(int which)
-{
-	int *ifindex = bpf_map_lookup_elem(&ifindex_map, &which);
-
-	return ifindex ? *ifindex : 0;
-}
-
-SEC("chk_egress") int tc_chk(struct __sk_buff *skb)
+SEC("classifier/chk_egress")
+int tc_chk(struct __sk_buff *skb)
 {
 	void *data_end = ctx_ptr(skb->data_end);
 	void *data = ctx_ptr(skb->data);
@@ -98,7 +83,8 @@ SEC("chk_egress") int tc_chk(struct __sk_buff *skb)
 	return !raw[0] && !raw[1] && !raw[2] ? TC_ACT_SHOT : TC_ACT_OK;
 }
 
-SEC("dst_ingress") int tc_dst(struct __sk_buff *skb)
+SEC("classifier/dst_ingress")
+int tc_dst(struct __sk_buff *skb)
 {
 	__u8 zero[ETH_ALEN * 2];
 	bool redirect = false;
@@ -119,10 +105,11 @@ SEC("dst_ingress") int tc_dst(struct __sk_buff *skb)
 	if (bpf_skb_store_bytes(skb, 0, &zero, sizeof(zero), 0) < 0)
 		return TC_ACT_SHOT;
 
-	return bpf_redirect_neigh(get_dev_ifindex(dev_src), NULL, 0, 0);
+	return bpf_redirect_neigh(IFINDEX_SRC, NULL, 0, 0);
 }
 
-SEC("src_ingress") int tc_src(struct __sk_buff *skb)
+SEC("classifier/src_ingress")
+int tc_src(struct __sk_buff *skb)
 {
 	__u8 zero[ETH_ALEN * 2];
 	bool redirect = false;
@@ -143,7 +130,7 @@ SEC("src_ingress") int tc_src(struct __sk_buff *skb)
 	if (bpf_skb_store_bytes(skb, 0, &zero, sizeof(zero), 0) < 0)
 		return TC_ACT_SHOT;
 
-	return bpf_redirect_neigh(get_dev_ifindex(dev_dst), NULL, 0, 0);
+	return bpf_redirect_neigh(IFINDEX_DST, NULL, 0, 0);
 }
 
 char __license[] SEC("license") = "GPL";

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

@@ -75,7 +75,8 @@ static __always_inline int fill_fib_params_v6(struct __sk_buff *skb,
 	return 0;
 }
 
-SEC("chk_egress") int tc_chk(struct __sk_buff *skb)
+SEC("classifier/chk_egress")
+int tc_chk(struct __sk_buff *skb)
 {
 	void *data_end = ctx_ptr(skb->data_end);
 	void *data = ctx_ptr(skb->data);
@@ -142,12 +143,14 @@ static __always_inline int tc_redir(struct __sk_buff *skb)
 /* these are identical, but keep them separate for compatibility with the
  * section names expected by test_tc_redirect.sh
  */
-SEC("dst_ingress") int tc_dst(struct __sk_buff *skb)
+SEC("classifier/dst_ingress")
+int tc_dst(struct __sk_buff *skb)
 {
 	return tc_redir(skb);
 }
 
-SEC("src_ingress") int tc_src(struct __sk_buff *skb)
+SEC("classifier/src_ingress")
+int tc_src(struct __sk_buff *skb)
 {
 	return tc_redir(skb);
 }

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

@@ -8,38 +8,25 @@
 
 #include <bpf/bpf_helpers.h>
 
-enum {
-	dev_src,
-	dev_dst,
-};
+static volatile const __u32 IFINDEX_SRC;
+static volatile const __u32 IFINDEX_DST;
 
-struct bpf_map_def SEC("maps") ifindex_map = {
-	.type		= BPF_MAP_TYPE_ARRAY,
-	.key_size	= sizeof(int),
-	.value_size	= sizeof(int),
-	.max_entries	= 2,
-};
-
-static __always_inline int get_dev_ifindex(int which)
-{
-	int *ifindex = bpf_map_lookup_elem(&ifindex_map, &which);
-
-	return ifindex ? *ifindex : 0;
-}
-
-SEC("chk_egress") int tc_chk(struct __sk_buff *skb)
+SEC("classifier/chk_egress")
+int tc_chk(struct __sk_buff *skb)
 {
 	return TC_ACT_SHOT;
 }
 
-SEC("dst_ingress") int tc_dst(struct __sk_buff *skb)
+SEC("classifier/dst_ingress")
+int tc_dst(struct __sk_buff *skb)
 {
-	return bpf_redirect_peer(get_dev_ifindex(dev_src), 0);
+	return bpf_redirect_peer(IFINDEX_SRC, 0);
 }
 
-SEC("src_ingress") int tc_src(struct __sk_buff *skb)
+SEC("classifier/src_ingress")
+int tc_src(struct __sk_buff *skb)
 {
-	return bpf_redirect_peer(get_dev_ifindex(dev_dst), 0);
+	return bpf_redirect_peer(IFINDEX_DST, 0);
 }
 
 char __license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/test_tc_redirect.sh

-#!/bin/bash
-# SPDX-License-Identifier: GPL-2.0
-#
-# This test sets up 3 netns (src <-> fwd <-> dst). There is no direct veth link
-# between src and dst. The netns fwd has veth links to each src and dst. The
-# client is in src and server in dst. The test installs a TC BPF program to each
-# host facing veth in fwd which calls into i) bpf_redirect_neigh() to perform the
-# neigh addr population and redirect or ii) bpf_redirect_peer() for namespace
-# switch from ingress side; it also installs a checker prog on the egress side
-# to drop unexpected traffic.
-
-if [[ $EUID -ne 0 ]]; then
-	echo "This script must be run as root"
-	echo "FAIL"
-	exit 1
-fi
-
-# check that needed tools are present
-command -v nc >/dev/null 2>&1 || \
-	{ echo >&2 "nc is not available"; exit 1; }
-command -v dd >/dev/null 2>&1 || \
-	{ echo >&2 "dd is not available"; exit 1; }
-command -v timeout >/dev/null 2>&1 || \
-	{ echo >&2 "timeout is not available"; exit 1; }
-command -v ping >/dev/null 2>&1 || \
-	{ echo >&2 "ping is not available"; exit 1; }
-if command -v ping6 >/dev/null 2>&1; then PING6=ping6; else PING6=ping; fi
-command -v perl >/dev/null 2>&1 || \
-	{ echo >&2 "perl is not available"; exit 1; }
-command -v jq >/dev/null 2>&1 || \
-	{ echo >&2 "jq is not available"; exit 1; }
-command -v bpftool >/dev/null 2>&1 || \
-	{ echo >&2 "bpftool is not available"; exit 1; }
-
-readonly GREEN='\033[0;92m'
-readonly RED='\033[0;31m'
-readonly NC='\033[0m' # No Color
-
-readonly PING_ARG="-c 3 -w 10 -q"
-
-readonly TIMEOUT=10
-
-readonly NS_SRC="ns-src-$(mktemp -u XXXXXX)"
-readonly NS_FWD="ns-fwd-$(mktemp -u XXXXXX)"
-readonly NS_DST="ns-dst-$(mktemp -u XXXXXX)"
-
-readonly IP4_SRC="172.16.1.100"
-readonly IP4_DST="172.16.2.100"
-
-readonly IP6_SRC="::1:dead:beef:cafe"
-readonly IP6_DST="::2:dead:beef:cafe"
-
-readonly IP4_SLL="169.254.0.1"
-readonly IP4_DLL="169.254.0.2"
-readonly IP4_NET="169.254.0.0"
-
-netns_cleanup()
-{
-	ip netns del ${NS_SRC}
-	ip netns del ${NS_FWD}
-	ip netns del ${NS_DST}
-}
-
-netns_setup()
-{
-	ip netns add "${NS_SRC}"
-	ip netns add "${NS_FWD}"
-	ip netns add "${NS_DST}"
-
-	ip link add veth_src type veth peer name veth_src_fwd
-	ip link add veth_dst type veth peer name veth_dst_fwd
-
-	ip link set veth_src netns ${NS_SRC}
-	ip link set veth_src_fwd netns ${NS_FWD}
-
-	ip link set veth_dst netns ${NS_DST}
-	ip link set veth_dst_fwd netns ${NS_FWD}
-
-	ip -netns ${NS_SRC} addr add ${IP4_SRC}/32 dev veth_src
-	ip -netns ${NS_DST} addr add ${IP4_DST}/32 dev veth_dst
-
-	# The fwd netns automatically get a v6 LL address / routes, but also
-	# needs v4 one in order to start ARP probing. IP4_NET route is added
-	# to the endpoints so that the ARP processing will reply.
-
-	ip -netns ${NS_FWD} addr add ${IP4_SLL}/32 dev veth_src_fwd
-	ip -netns ${NS_FWD} addr add ${IP4_DLL}/32 dev veth_dst_fwd
-
-	ip -netns ${NS_SRC} addr add ${IP6_SRC}/128 dev veth_src nodad
-	ip -netns ${NS_DST} addr add ${IP6_DST}/128 dev veth_dst nodad
-
-	ip -netns ${NS_SRC} link set dev veth_src up
-	ip -netns ${NS_FWD} link set dev veth_src_fwd up
-
-	ip -netns ${NS_DST} link set dev veth_dst up
-	ip -netns ${NS_FWD} link set dev veth_dst_fwd up
-
-	ip -netns ${NS_SRC} route add ${IP4_DST}/32 dev veth_src scope global
-	ip -netns ${NS_SRC} route add ${IP4_NET}/16 dev veth_src scope global
-	ip -netns ${NS_FWD} route add ${IP4_SRC}/32 dev veth_src_fwd scope global
-
-	ip -netns ${NS_SRC} route add ${IP6_DST}/128 dev veth_src scope global
-	ip -netns ${NS_FWD} route add ${IP6_SRC}/128 dev veth_src_fwd scope global
-
-	ip -netns ${NS_DST} route add ${IP4_SRC}/32 dev veth_dst scope global
-	ip -netns ${NS_DST} route add ${IP4_NET}/16 dev veth_dst scope global
-	ip -netns ${NS_FWD} route add ${IP4_DST}/32 dev veth_dst_fwd scope global
-
-	ip -netns ${NS_DST} route add ${IP6_SRC}/128 dev veth_dst scope global
-	ip -netns ${NS_FWD} route add ${IP6_DST}/128 dev veth_dst_fwd scope global
-
-	fmac_src=$(ip netns exec ${NS_FWD} cat /sys/class/net/veth_src_fwd/address)
-	fmac_dst=$(ip netns exec ${NS_FWD} cat /sys/class/net/veth_dst_fwd/address)
-
-	ip -netns ${NS_SRC} neigh add ${IP4_DST} dev veth_src lladdr $fmac_src
-	ip -netns ${NS_DST} neigh add ${IP4_SRC} dev veth_dst lladdr $fmac_dst
-
-	ip -netns ${NS_SRC} neigh add ${IP6_DST} dev veth_src lladdr $fmac_src
-	ip -netns ${NS_DST} neigh add ${IP6_SRC} dev veth_dst lladdr $fmac_dst
-}
-
-netns_test_connectivity()
-{
-	set +e
-
-	ip netns exec ${NS_DST} bash -c "nc -4 -l -p 9004 &"
-	ip netns exec ${NS_DST} bash -c "nc -6 -l -p 9006 &"
-
-	TEST="TCPv4 connectivity test"
-	ip netns exec ${NS_SRC} bash -c "timeout ${TIMEOUT} dd if=/dev/zero bs=1000 count=100 > /dev/tcp/${IP4_DST}/9004"
-	if [ $? -ne 0 ]; then
-		echo -e "${TEST}: ${RED}FAIL${NC}"
-		exit 1
-	fi
-	echo -e "${TEST}: ${GREEN}PASS${NC}"
-
-	TEST="TCPv6 connectivity test"
-	ip netns exec ${NS_SRC} bash -c "timeout ${TIMEOUT} dd if=/dev/zero bs=1000 count=100 > /dev/tcp/${IP6_DST}/9006"
-	if [ $? -ne 0 ]; then
-		echo -e "${TEST}: ${RED}FAIL${NC}"
-		exit 1
-	fi
-	echo -e "${TEST}: ${GREEN}PASS${NC}"
-
-	TEST="ICMPv4 connectivity test"
-	ip netns exec ${NS_SRC} ping  $PING_ARG ${IP4_DST}
-	if [ $? -ne 0 ]; then
-		echo -e "${TEST}: ${RED}FAIL${NC}"
-		exit 1
-	fi
-	echo -e "${TEST}: ${GREEN}PASS${NC}"
-
-	TEST="ICMPv6 connectivity test"
-	ip netns exec ${NS_SRC} $PING6 $PING_ARG ${IP6_DST}
-	if [ $? -ne 0 ]; then
-		echo -e "${TEST}: ${RED}FAIL${NC}"
-		exit 1
-	fi
-	echo -e "${TEST}: ${GREEN}PASS${NC}"
-
-	set -e
-}
-
-hex_mem_str()
-{
-	perl -e 'print join(" ", unpack("(H2)8", pack("L", @ARGV)))' $1
-}
-
-netns_setup_bpf()
-{
-	local obj=$1
-	local use_forwarding=${2:-0}
-
-	ip netns exec ${NS_FWD} tc qdisc add dev veth_src_fwd clsact
-	ip netns exec ${NS_FWD} tc filter add dev veth_src_fwd ingress bpf da obj $obj sec src_ingress
-	ip netns exec ${NS_FWD} tc filter add dev veth_src_fwd egress  bpf da obj $obj sec chk_egress
-
-	ip netns exec ${NS_FWD} tc qdisc add dev veth_dst_fwd clsact
-	ip netns exec ${NS_FWD} tc filter add dev veth_dst_fwd ingress bpf da obj $obj sec dst_ingress
-	ip netns exec ${NS_FWD} tc filter add dev veth_dst_fwd egress  bpf da obj $obj sec chk_egress
-
-	if [ "$use_forwarding" -eq "1" ]; then
-		# bpf_fib_lookup() checks if forwarding is enabled
-		ip netns exec ${NS_FWD} sysctl -w net.ipv4.ip_forward=1
-		ip netns exec ${NS_FWD} sysctl -w net.ipv6.conf.veth_dst_fwd.forwarding=1
-		ip netns exec ${NS_FWD} sysctl -w net.ipv6.conf.veth_src_fwd.forwarding=1
-		return 0
-	fi
-
-	veth_src=$(ip netns exec ${NS_FWD} cat /sys/class/net/veth_src_fwd/ifindex)
-	veth_dst=$(ip netns exec ${NS_FWD} cat /sys/class/net/veth_dst_fwd/ifindex)
-
-	progs=$(ip netns exec ${NS_FWD} bpftool net --json | jq -r '.[] | .tc | map(.id) | .[]')
-	for prog in $progs; do
-		map=$(bpftool prog show id $prog --json | jq -r '.map_ids | .? | .[]')
-		if [ ! -z "$map" ]; then
-			bpftool map update id $map key hex $(hex_mem_str 0) value hex $(hex_mem_str $veth_src)
-			bpftool map update id $map key hex $(hex_mem_str 1) value hex $(hex_mem_str $veth_dst)
-		fi
-	done
-}
-
-trap netns_cleanup EXIT
-set -e
-
-netns_setup
-netns_setup_bpf test_tc_neigh.o
-netns_test_connectivity
-netns_cleanup
-netns_setup
-netns_setup_bpf test_tc_neigh_fib.o 1
-netns_test_connectivity
-netns_cleanup
-netns_setup
-netns_setup_bpf test_tc_peer.o
-netns_test_connectivity