One remaining difference between test_tcp_check_syncookie.sh and
btf_skc_cls_ingress is a small test on the mss value embedded in the
cookie generated with the eBPF helper.
Bring the corresponding test in btf_skc_cls_ingress.
Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com>
---
tools/testing/selftests/bpf/prog_tests/btf_skc_cls_ingress.c | 7 +++++++
tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c | 2 ++
2 files changed, 9 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_skc_cls_ingress.c b/tools/testing/selftests/bpf/prog_tests/btf_skc_cls_ingress.c
index e0f8fe818f4230a1d5bf0118133c5a9fb50345e1..64601bafdd23e7fb13ebd496ac914660685f1efc 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf_skc_cls_ingress.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf_skc_cls_ingress.c
@@ -27,6 +27,8 @@
#define SERVER_ADDR_IPV4 "127.0.0.1"
#define SERVER_ADDR_IPV6 "::1"
#define SERVER_ADDR_DUAL "::0"
+/* RFC791, 576 for minimal IPv4 datagram, minus 40 bytes of TCP header */
+#define MIN_IPV4_MSS 536
static struct netns_obj *prepare_netns(struct test_btf_skc_cls_ingress *skel)
{
@@ -73,6 +75,7 @@ static void reset_test(struct test_btf_skc_cls_ingress *skel)
skel->bss->recv_cookie = 0;
skel->bss->gen_cookie = 0;
skel->bss->linum = 0;
+ skel->bss->mss = 0;
}
static void print_err_line(struct test_btf_skc_cls_ingress *skel)
@@ -184,6 +187,10 @@ static void run_test(struct test_btf_skc_cls_ingress *skel, bool gen_cookies,
"syncookie properly generated");
ASSERT_EQ(skel->bss->gen_cookie, skel->bss->recv_cookie,
"matching syncookies on client and server");
+ ASSERT_GT(skel->bss->mss, MIN_IPV4_MSS,
+ "MSS in cookie min value");
+ ASSERT_LT(skel->bss->mss, USHRT_MAX,
+ "MSS in cookie max value");
}
done:
diff --git a/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c b/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c
index cd528f8792ff2eb14683cbc13e8b0f3fd38329e9..3810ce98d3d54276f9a0130a887f59c79a21288e 100644
--- a/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c
+++ b/tools/testing/selftests/bpf/progs/test_btf_skc_cls_ingress.c
@@ -15,6 +15,7 @@ __u16 listen_tp_sport = 0;
__u16 req_sk_sport = 0;
__u32 recv_cookie = 0;
__u32 gen_cookie = 0;
+__u32 mss = 0;
__u32 linum = 0;
#define LOG() ({ if (!linum) linum = __LINE__; })
@@ -46,6 +47,7 @@ static void test_syncookie_helper(void *iphdr, int iphdr_size,
LOG();
} else {
gen_cookie = (__u32)mss_cookie;
+ mss = mss_cookie >> 32;
}
} else if (gen_cookie) {
/* It was in cookie mode */
--
2.46.2