[PATCH bpf-next v7 6/7] selftests/bpf: add bpf_icmp_send kfunc tc tests

[Mahe Tardy <mahe.tardy@gmail.com>]

This test is similar to the one with cgroup_skb programs but uses tc
egress instead.

Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com>
---
 .../bpf/prog_tests/icmp_send_kfunc.c          | 25 ++++++++
 tools/testing/selftests/bpf/progs/icmp_send.c | 60 +++++++++++++++++++
 2 files changed, 85 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/icmp_send_kfunc.c b/tools/testing/selftests/bpf/prog_tests/icmp_send_kfunc.c
index 1d6900d6a8f8..51f809ea6896 100644
--- a/tools/testing/selftests/bpf/prog_tests/icmp_send_kfunc.c
+++ b/tools/testing/selftests/bpf/prog_tests/icmp_send_kfunc.c
@@ -176,3 +176,28 @@ void test_icmp_send_unreach_cgroup(void)
 	icmp_send__destroy(skel);
 	close(cgroup_fd);
 }
+
+void test_icmp_send_unreach_tc(void)
+{
+	LIBBPF_OPTS(bpf_tcx_opts, opts);
+	struct icmp_send *skel;
+	struct bpf_link *link = NULL;
+
+	skel = icmp_send__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "skel_open"))
+		goto cleanup;
+
+	link = bpf_program__attach_tcx(skel->progs.tc_egress, 1, &opts);
+	if (!ASSERT_OK_PTR(link, "prog_attach"))
+		goto cleanup;
+
+	if (test__start_subtest("ipv4"))
+		run_icmp_test(skel, AF_INET, "127.0.0.1", NR_ICMP_UNREACH);
+
+	if (test__start_subtest("ipv6"))
+		run_icmp_test(skel, AF_INET6, "::1", ICMPV6_REJECT_ROUTE);
+
+cleanup:
+	bpf_link__destroy(link);
+	icmp_send__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/icmp_send.c b/tools/testing/selftests/bpf/progs/icmp_send.c
index 6e1ba539eeb0..5fa5467bdb70 100644
--- a/tools/testing/selftests/bpf/progs/icmp_send.c
+++ b/tools/testing/selftests/bpf/progs/icmp_send.c
@@ -2,6 +2,7 @@
 #include "vmlinux.h"
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_endian.h>
+#include "bpf_tracing_net.h"

 /* 127.0.0.1 in host byte order */
 #define SERVER_IP 0x7F000001
@@ -65,4 +66,63 @@ int egress(struct __sk_buff *skb)
 	return SK_DROP;
 }

+SEC("tc/egress")
+int tc_egress(struct __sk_buff *skb)
+{
+	void *data = (void *)(long)skb->data;
+	void *data_end = (void *)(long)skb->data_end;
+	struct ethhdr *eth;
+	struct iphdr *iph;
+	struct ipv6hdr *ip6h;
+	struct tcphdr *tcph;
+
+	eth = data;
+	if ((void *)(eth + 1) > data_end)
+		return TCX_PASS;
+
+	if (eth->h_proto == bpf_htons(ETH_P_IP)) {
+		iph = (void *)(eth + 1);
+		if ((void *)(iph + 1) > data_end)
+			return TCX_PASS;
+
+		if (iph->protocol != IPPROTO_TCP ||
+		    iph->daddr != bpf_htonl(SERVER_IP))
+			return TCX_PASS;
+
+		tcph = (void *)iph + iph->ihl * 4;
+		if ((void *)(tcph + 1) > data_end)
+			return TCX_PASS;
+
+		if (tcph->dest != bpf_htons(server_port))
+			return TCX_PASS;
+
+	} else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) {
+		ip6h = (void *)(eth + 1);
+		if ((void *)(ip6h + 1) > data_end)
+			return TCX_PASS;
+
+		if (ip6h->nexthdr != IPPROTO_TCP)
+			return TCX_PASS;
+
+		if (ip6h->daddr.in6_u.u6_addr32[0] != 0 ||
+		    ip6h->daddr.in6_u.u6_addr32[1] != 0 ||
+		    ip6h->daddr.in6_u.u6_addr32[2] != 0 ||
+		    ip6h->daddr.in6_u.u6_addr32[3] != bpf_htonl(SERVER_IP6_LO))
+			return TCX_PASS;
+
+		tcph = (void *)(ip6h + 1);
+		if ((void *)(tcph + 1) > data_end)
+			return TCX_PASS;
+
+		if (tcph->dest != bpf_htons(server_port))
+			return TCX_PASS;
+	} else {
+		return TCX_PASS;
+	}
+
+	kfunc_ret = bpf_icmp_send(skb, unreach_type, unreach_code);
+
+	return TCX_DROP;
+}
+
 char LICENSE[] SEC("license") = "Dual BSD/GPL";
--
2.34.1