diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index 7cdbd24..ce4a257 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -337,6 +337,10 @@
 
 server5-tricky-ip-san.crt: server5.key
 	$(OPENSSL) req -x509 -new -subj "/C=UK/O=Mbed TLS/CN=Mbed TLS Tricky IP SAN" -set_serial 77 -config $(test_ca_config_file) -extensions tricky_ip_san -days 3650 -sha256 -key server5.key -out $@
+	
+server5-directoryname.crt: server5.key
+	$(OPENSSL) req -x509 -new -subj "/C=UK/O=Mbed TLS/CN=Mbed TLS directoryName SAN" -set_serial 77 -config $(test_ca_config_file) -extensions directory_name_san -days 3650 -sha256 -key server5.key -out $@
+
 all_final += server5-tricky-ip-san.crt
 
 rsa_single_san_uri.crt.der: rsa_single_san_uri.key
diff --git a/tests/data_files/server5-directoryname.crt b/tests/data_files/server5-directoryname.crt
new file mode 100644
index 0000000..afa88b3
--- /dev/null
+++ b/tests/data_files/server5-directoryname.crt
@@ -0,0 +1,13 @@
+-----BEGIN CERTIFICATE-----
+MIIB7jCCAZSgAwIBAgIBTTAKBggqhkjOPQQDAjBFMQswCQYDVQQGEwJVSzERMA8G
+A1UECgwITWJlZCBUTFMxIzAhBgNVBAMMGk1iZWQgVExTIGRpcmVjdG9yeU5hbWUg
+U0FOMB4XDTIzMDExMDE2NTkyOVoXDTMzMDEwNzE2NTkyOVowRTELMAkGA1UEBhMC
+VUsxETAPBgNVBAoMCE1iZWQgVExTMSMwIQYDVQQDDBpNYmVkIFRMUyBkaXJlY3Rv
+cnlOYW1lIFNBTjBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABDfMVtl2CR5acj7H
+WS3/IG7ufPkGkXTQrRS192giWWKSTuUA2CMR/+ov0jRdXRa9iojCa3cNVc2KKg76
+Aci07f+jdTBzMFIGA1UdEQRLMEmkRzBFMQswCQYDVQQGEwJVSzERMA8GA1UECgwI
+TWJlZCBUTFMxIzAhBgNVBAMMGk1iZWQgVExTIGRpcmVjdG9yeU5hbWUgU0FOMB0G
+A1UdDgQWBBRQYaWP1AfZ14IBDOVlf4xjRqcTvjAKBggqhkjOPQQDAgNIADBFAiBr
+PtyaL8tF+jghNK32ZnWriCp2k7Aq+QVuef+6+sSH6AIhAIKw+o0J2Pu27ulHFIzI
+MdFECpZ3nqAGbTOTOMX6LoDh
+-----END CERTIFICATE-----
diff --git a/tests/data_files/test-ca.opensslconf b/tests/data_files/test-ca.opensslconf
index 8f8385a..16afebf 100644
--- a/tests/data_files/test-ca.opensslconf
+++ b/tests/data_files/test-ca.opensslconf
@@ -99,3 +99,11 @@
 keyUsage = cRLSign
 subjectAltName=otherName:1.3.6.1.5.5.7.8.4;SEQ:nonprintable_hw_module_name
 nsCertType=client
+
+[directory_name_san]
+subjectAltName=dirName:dirname_sect
+
+[dirname_sect]
+C=UK
+O=Mbed TLS
+CN=Mbed TLS directoryName SAN