diff --git a/libcommon/base64_common.c b/libcommon/base64_common.c
index 4acdc9a1..9ce2d012 100644
--- a/libcommon/base64_common.c
+++ b/libcommon/base64_common.c
@@ -71,6 +71,8 @@ int mosquitto_base64_decode(const char *in, unsigned char **decoded, unsigned in
 	int rc = 1;
 
 	slen = strlen(in);
+	*decoded = NULL;
+	*decoded_len = 0;
 
 	b64 = BIO_new(BIO_f_base64());
 	if(!b64){
diff --git a/test/unit/libcommon/CMakeLists.txt b/test/unit/libcommon/CMakeLists.txt
index d4f3be37..6dc5974a 100644
--- a/test/unit/libcommon/CMakeLists.txt
+++ b/test/unit/libcommon/CMakeLists.txt
@@ -1,4 +1,5 @@
 add_executable(libcommon-test
+	base64_test.c
 	property_add.c
 	property_value.c
 	strings_test.c
diff --git a/test/unit/libcommon/Makefile b/test/unit/libcommon/Makefile
index 913bcbfa..c4293113 100644
--- a/test/unit/libcommon/Makefile
+++ b/test/unit/libcommon/Makefile
@@ -13,6 +13,7 @@ ifeq ($(WITH_TLS),yes)
 endif
 
 TEST_OBJS = \
+	base64_test.o \
 	property_add.o \
 	property_value.o \
 	strings_test.o \
diff --git a/test/unit/libcommon/base64_test.c b/test/unit/libcommon/base64_test.c
new file mode 100644
index 00000000..73b1b9e2
--- /dev/null
+++ b/test/unit/libcommon/base64_test.c
@@ -0,0 +1,157 @@
+#include <CUnit/CUnit.h>
+#include <CUnit/Basic.h>
+
+#include "mosquitto/mqtt_protocol.h"
+#include "property_common.h"
+
+//int mosquitto_base64_encode(const unsigned char *in, size_t in_len, char **encoded);
+//int mosquitto_base64_decode(const char *in, unsigned char **decoded, unsigned int *decoded_len);
+
+static void check_encode(const char *input, size_t in_len, const char *expected_output)
+{
+	char *encoded;
+	int rc = mosquitto_base64_encode((const unsigned char *)input, in_len, &encoded);
+
+	CU_ASSERT_EQUAL(rc, MOSQ_ERR_SUCCESS);
+	CU_ASSERT_STRING_EQUAL(encoded, expected_output);
+	if(strcmp(encoded, expected_output)){
+		printf("%s || %s\n", encoded, expected_output);
+	}
+	mosquitto_free(encoded);
+}
+
+
+static void check_decode(const char *input, int expected_rc, const char *expected_output, unsigned int expected_len)
+{
+	unsigned char *decoded;
+	unsigned int len;
+	int rc = mosquitto_base64_decode(input, &decoded, &len);
+
+	CU_ASSERT_EQUAL(rc, expected_rc);
+	if(rc != expected_rc){
+		printf("rc: %d||%d\n", rc, expected_rc);
+	}
+	if(len != expected_len){
+		printf("len: %d||%d\n", len, expected_len);
+	}
+	CU_ASSERT_EQUAL(len, expected_len);
+	if(decoded){
+		CU_ASSERT_EQUAL(memcmp(decoded, expected_output, len), 0);
+		mosquitto_free(decoded);
+	}
+}
+
+
+static void TEST_encode_empty(void)
+{
+	check_encode("", 0, "");
+}
+
+
+static void TEST_encode_string_lengths(void)
+{
+	check_encode("a", 1, "YQ==");
+	check_encode("ab", 2, "YWI=");
+	check_encode("abc", 3, "YWJj");
+	check_encode("abcd", 4, "YWJjZA==");
+	check_encode("abcde", 5, "YWJjZGU=");
+	check_encode("abcdef", 6, "YWJjZGVm");
+	check_encode("abcdefg", 7, "YWJjZGVmZw==");
+}
+
+
+static void TEST_encode_binary(void)
+{
+	const char a[1] = {0};
+	const char b[2] = {0, 1};
+	const char c[3] = {0, 1, 2};
+	const char d[4] = {0, 1, 2, 3};
+	const char e[5] = {0, 1, 2, 3, 4};
+	const char f[6] = {0, 1, 2, 3, 4, 5};
+	const char g[7] = {0, 1, 2, 3, 4, 5, 6};
+
+	check_encode(a, 1, "AA==");
+	check_encode(b, 2, "AAE=");
+	check_encode(c, 3, "AAEC");
+	check_encode(d, 4, "AAECAw==");
+	check_encode(e, 5, "AAECAwQ=");
+	check_encode(f, 6, "AAECAwQF");
+	check_encode(g, 7, "AAECAwQFBg==");
+}
+
+
+static void TEST_decode_empty(void)
+{
+	check_decode("", 1, "", 0);
+}
+
+
+static void TEST_decode_invalid(void)
+{
+	check_decode("abc", 1, "", 0);
+}
+
+
+static void TEST_decode_string_lengths(void)
+{
+	check_decode("YQ==", MOSQ_ERR_SUCCESS, "a", 1);
+	check_decode("YWI=", MOSQ_ERR_SUCCESS, "ab", 2);
+	check_decode("YWJj", MOSQ_ERR_SUCCESS, "abc", 3);
+	check_decode("YWJjZA==", MOSQ_ERR_SUCCESS, "abcd", 4);
+	check_decode("YWJjZGU=", MOSQ_ERR_SUCCESS, "abcde", 5);
+	check_decode("YWJjZGVm", MOSQ_ERR_SUCCESS, "abcdef", 6);
+	check_decode("YWJjZGVmZw==", MOSQ_ERR_SUCCESS, "abcdefg", 7);
+}
+
+
+static void TEST_decode_binary(void)
+{
+	const char a[1] = {0};
+	const char b[2] = {0, 1};
+	const char c[3] = {0, 1, 2};
+	const char d[4] = {0, 1, 2, 3};
+	const char e[5] = {0, 1, 2, 3, 4};
+	const char f[6] = {0, 1, 2, 3, 4, 5};
+	const char g[7] = {0, 1, 2, 3, 4, 5, 6};
+
+	check_decode("AA==", MOSQ_ERR_SUCCESS, a, 1);
+	check_decode("AAE=", MOSQ_ERR_SUCCESS, b, 2);
+	check_decode("AAEC", MOSQ_ERR_SUCCESS, c, 3);
+	check_decode("AAECAw==", MOSQ_ERR_SUCCESS, d, 4);
+	check_decode("AAECAwQ=", MOSQ_ERR_SUCCESS, e, 5);
+	check_decode("AAECAwQF", MOSQ_ERR_SUCCESS, f, 6);
+	check_decode("AAECAwQFBg==", MOSQ_ERR_SUCCESS, g, 7);
+}
+
+
+/* ========================================================================
+ * TEST SUITE SETUP
+ * ======================================================================== */
+
+
+int init_base64_tests(void)
+{
+	CU_pSuite test_suite = NULL;
+
+	test_suite = CU_add_suite("base64", NULL, NULL);
+	if(!test_suite){
+		printf("Error adding CUnit base64 test suite.\n");
+		return 1;
+	}
+
+	if(0
+			|| !CU_add_test(test_suite, "Encode Empty", TEST_encode_empty)
+			|| !CU_add_test(test_suite, "Encode String lengths", TEST_encode_string_lengths)
+			|| !CU_add_test(test_suite, "Encode Binary", TEST_encode_binary)
+			|| !CU_add_test(test_suite, "Decode Empty", TEST_decode_empty)
+			|| !CU_add_test(test_suite, "Decode Invalid", TEST_decode_invalid)
+			|| !CU_add_test(test_suite, "Decode String lengths", TEST_decode_string_lengths)
+			|| !CU_add_test(test_suite, "Decode Binary", TEST_decode_binary)
+			){
+
+		printf("Error adding Property Add CUnit tests.\n");
+		return 1;
+	}
+
+	return 0;
+}
diff --git a/test/unit/libcommon/test.c b/test/unit/libcommon/test.c
index ad240d48..9aa5187f 100644
--- a/test/unit/libcommon/test.c
+++ b/test/unit/libcommon/test.c
@@ -4,6 +4,7 @@
 #include <CUnit/CUnit.h>
 #include <CUnit/Basic.h>
 
+int init_base64_tests(void);
 int init_property_add_tests(void);
 int init_property_value_tests(void);
 int init_strings_tests(void);
@@ -25,6 +26,7 @@ int main(int argc, char *argv[])
 	}
 
 	if(0
+			|| init_base64_tests()
 			|| init_property_add_tests()
 			|| init_property_value_tests()
 			|| init_strings_tests()
diff --git a/test/unit/libcommon/topic_test.c b/test/unit/libcommon/topic_test.c
index 2ef46749..afdf2a1c 100644
--- a/test/unit/libcommon/topic_test.c
+++ b/test/unit/libcommon/topic_test.c
@@ -1392,6 +1392,7 @@ static void TEST_pub_topic_invalid(void)
 	pub_topic_helper("pub/topic#", MOSQ_ERR_INVAL);
 	pub_topic_helper("pub/topic/#", MOSQ_ERR_INVAL);
 	pub_topic_helper("+/pub/topic", MOSQ_ERR_INVAL);
+	pub_topic_helper("//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////a", MOSQ_ERR_INVAL);
 }
 
 
@@ -1440,6 +1441,7 @@ static void TEST_sub_topic_invalid(void)
 	sub_topic_helper("sub/#topic", MOSQ_ERR_INVAL);
 	sub_topic_helper("sub/topic#", MOSQ_ERR_INVAL);
 	sub_topic_helper("#/sub/topic", MOSQ_ERR_INVAL);
+	sub_topic_helper("//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////a", MOSQ_ERR_INVAL);
 }