diff --git a/include/mbedtls/oid.h b/include/mbedtls/oid.h
index c516b7aaf..1e96856e2 100644
--- a/include/mbedtls/oid.h
+++ b/include/mbedtls/oid.h
@@ -212,7 +212,7 @@
  * { iso(1) identified-organization(3) dod(6) internet(1)
  *                      private(4) enterprise(1) WiSUN(45605) FieldAreaNetwork(1) }
  */
-#define MBEDTLS_OID_WISUN_FAN                  MBEDTLS_OID_INTERNET "\x04\x01\x82\xe4\x25\x01"
+#define MBEDTLS_OID_WISUN_FAN                   MBEDTLS_OID_INTERNET "\x04\x01\x82\xe4\x25\x01"
 
 #define MBEDTLS_OID_ON                          MBEDTLS_OID_PKIX "\x08" /**< id-on OBJECT IDENTIFIER ::= { id-pkix 8 } */
 #define MBEDTLS_OID_ON_HW_MODULE_NAME           MBEDTLS_OID_ON "\x04" /**< id-on-hardwareModuleName OBJECT IDENTIFIER ::= { id-on 4 } */
diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index d139bfa06..d1af18ce7 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -184,6 +184,9 @@ server5-othername.crt: server5.key
 server5-unsupported_othername.crt: server5.key
 	$(OPENSSL) req -x509 -new -subj "/C=UK/O=Mbed TLS/CN=Mbed TLS unsupported othername SAN" -set_serial 77 -config $(test_ca_config_file) -extensions unsupoported_othername_san -days 3650 -sha256 -key $< -out $@
 
+server5-fan.crt: server5.key
+	$(OPENSSL) req -x509 -new -subj "/C=UK/O=Mbed TLS/CN=Mbed TLS FAN" -set_serial 77 -config $(test_ca_config_file) -extensions fan_cert -days 3650 -sha256 -key server5.key -out $@
+
 server10-badsign.crt: server10.crt
 	{ head -n-2 $<; tail -n-2 $< | sed -e '1s/0\(=*\)$$/_\1/' -e '1s/[^_=]\(=*\)$$/0\1/' -e '1s/_/1/'; } > $@
 all_final += server10-badsign.crt
diff --git a/tests/data_files/server5-fan.crt b/tests/data_files/server5-fan.crt
new file mode 100644
index 000000000..dc1eb380c
--- /dev/null
+++ b/tests/data_files/server5-fan.crt
@@ -0,0 +1,10 @@
+-----BEGIN CERTIFICATE-----
+MIIBdTCCARugAwIBAgIBTTAKBggqhkjOPQQDAjA3MQswCQYDVQQGEwJVSzERMA8G
+A1UECgwITWJlZCBUTFMxFTATBgNVBAMMDE1iZWQgVExTIEZBTjAeFw0xOTAzMjUw
+OTAzNDZaFw0yOTAzMjIwOTAzNDZaMDcxCzAJBgNVBAYTAlVLMREwDwYDVQQKDAhN
+YmVkIFRMUzEVMBMGA1UEAwwMTWJlZCBUTFMgRkFOMFkwEwYHKoZIzj0CAQYIKoZI
+zj0DAQcDQgAEN8xW2XYJHlpyPsdZLf8gbu58+QaRdNCtFLX3aCJZYpJO5QDYIxH/
+6i/SNF1dFr2KiMJrdw1VzYoqDvoByLTt/6MYMBYwFAYDVR0lBA0wCwYJKwYBBAGC
+5CUBMAoGCCqGSM49BAMCA0gAMEUCIQDp/Q5FaVy3YNeJflQKLGycQZoH6V3FQnLq
+ERUCeimLIAIgdyiA4KdHxkpQhC1L1KfmxG8YJqu31FBjmNw00Sv8J9k=
+-----END CERTIFICATE-----
diff --git a/tests/data_files/test-ca.opensslconf b/tests/data_files/test-ca.opensslconf
index 5f71532ce..d2c5c0630 100644
--- a/tests/data_files/test-ca.opensslconf
+++ b/tests/data_files/test-ca.opensslconf
@@ -51,6 +51,9 @@ certificatePolicies = 1.2.3.4
 policyIdentifier = 2.5.29.32.0
 CPS.1 ="CPS uri string"
 
+[fan_cert]
+extendedKeyUsage = 1.3.6.1.4.1.45605.1
+
 [noext_ca]
 basicConstraints = CA:true
 
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 6fcf80564..d3afe1f88 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -98,6 +98,10 @@ X509 Certificate information EC, SHA256 Digest, hardware module name SAN
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
 x509_cert_info:"data_files/server5-othername.crt":"cert. version     \: 3\nserial number     \: 4D\nissuer name       \: C=UK, O=Mbed TLS, CN=Mbed TLS othername SAN\nsubject name      \: C=UK, O=Mbed TLS, CN=Mbed TLS othername SAN\nissued  on        \: 2019-03-24 09\:06\:02\nexpires on        \: 2029-03-21 09\:06\:02\nsigned using      \: ECDSA with SHA256\nEC key size       \: 256 bits\nsubject alt name  \:\n    otherName \:\n        hardware module name \:\n            hardware type          \: 1.3.6.1.4.1.17.3\n            hardware serial number \: 123456\n"
 
+X509 Certificate information EC, SHA256 Digest, Wisun Fan device
+depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECDSA_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_SHA256_C
+x509_cert_info:"data_files/server5-fan.crt":"cert. version     \: 3\nserial number     \: 4D\nissuer name       \: C=UK, O=Mbed TLS, CN=Mbed TLS FAN\nsubject name      \: C=UK, O=Mbed TLS, CN=Mbed TLS FAN\nissued  on        \: 2019-03-25 09\:03\:46\nexpires on        \: 2029-03-22 09\:03\:46\nsigned using      \: ECDSA with SHA256\nEC key size       \: 256 bits\next key usage     \: Wi-SUN Alliance Field Area Network (FAN)\n"
+
 X509 Certificate information, NS Cert Type
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_RSA_C:MBEDTLS_SHA1_C
 x509_cert_info:"data_files/server1.cert_type.crt":"cert. version     \: 3\nserial number     \: 01\nissuer name       \: C=NL, O=PolarSSL, CN=PolarSSL Test CA\nsubject name      \: C=NL, O=PolarSSL, CN=PolarSSL Server 1\nissued  on        \: 2011-02-12 14\:44\:06\nexpires on        \: 2021-02-12 14\:44\:06\nsigned using      \: RSA with SHA1\nRSA key size      \: 2048 bits\nbasic constraints \: CA=false\ncert. type        \: SSL Server\n"