Index: head/lib/libbsnmp/Makefile
===================================================================
--- head/lib/libbsnmp/Makefile
+++ head/lib/libbsnmp/Makefile
@@ -1,5 +1,6 @@
 # $FreeBSD$
 
 SUBDIR=	libbsnmp
+SUBDIR.${MK_TESTS}+= tests
 
 .include <bsd.subdir.mk>
Index: head/lib/libbsnmp/tests/Makefile
===================================================================
--- head/lib/libbsnmp/tests/Makefile
+++ head/lib/libbsnmp/tests/Makefile
@@ -0,0 +1,11 @@
+# $FreeBSD$
+
+.include <bsd.own.mk>
+
+ATF_TESTS_C+=	bsnmpd_test
+
+SRCS.bsmpd_test=	bsnmpd_test.c
+
+LIBADD+=	bsnmp
+
+.include <bsd.test.mk>
Index: head/lib/libbsnmp/tests/bsnmpd_test.c
===================================================================
--- head/lib/libbsnmp/tests/bsnmpd_test.c
+++ head/lib/libbsnmp/tests/bsnmpd_test.c
@@ -0,0 +1,53 @@
+/*-
+ * Copyright (c) 2020 Dell EMC
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <bsnmp/asn1.h>
+
+#include <atf-c.h>
+
+ATF_TC_WITHOUT_HEAD(sa_19_20_bsnmp_test);
+ATF_TC_BODY(sa_19_20_bsnmp_test, tc)
+{
+	struct asn_buf b = {};
+	char test_buf[] = { 0x25, 0x7f };
+	enum asn_err err;
+	asn_len_t len;
+	u_char type;
+
+	b.asn_cptr = test_buf;
+	b.asn_len = sizeof(test_buf);
+
+	err = asn_get_header(&b, &type, &len);
+	ATF_CHECK_EQ(ASN_ERR_EOBUF, err);
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+	ATF_TP_ADD_TC(tp, sa_19_20_bsnmp_test);
+	return (atf_no_error());
+}