diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index 363ac37..ce2ba6d 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -116,13 +116,28 @@
 test_ca_key_file_ec = test-ca2.key
 
 test-ca2.req.sha256: $(test_ca_key_file_ec)
-	$(MBEDTLS_CERT_REQ) output_file=$@ filename=$(test_ca_key_file_ec) subject_name="C=NL,O=PolarSSL,CN=Polarssl Test EC CA" md=SHA256
+	$(MBEDTLS_CERT_REQ) output_file=$@ filename=$(test_ca_key_file_ec) \
+	subject_name="C=NL,O=PolarSSL,CN=Polarssl Test EC CA" md=SHA256
 all_intermediate += test-ca2.req.sha256
 
 test-ca2.crt: $(test_ca_key_file_ec) test-ca2.req.sha256
-	$(MBEDTLS_CERT_WRITE) is_ca=1 serial=13926223505202072808 request_file=test-ca2.req.sha256 selfsign=1 issuer_name="C=NL,O=PolarSSL,CN=Polarssl Test EC CA" issuer_key=$(test_ca_key_file_ec) not_before=20190210144400 not_after=20290210144400 md=SHA256 version=3 output_file=$@
+	$(MBEDTLS_CERT_WRITE) is_ca=1 serial=13926223505202072808 selfsign=1 \
+		request_file=test-ca2.req.sha256 \
+		issuer_name="C=NL,O=PolarSSL,CN=Polarssl Test EC CA" \
+		issuer_key=$(test_ca_key_file_ec) \
+		not_before=20190210144400 not_after=20290210144400 \
+		md=SHA256 version=3 output_file=$@
 all_final += test-ca2.crt
 
+test-ca2.ku-%.crt: test-ca2.ku-%.crt.openssl.v3_ext $(test_ca_key_file_ec) test-ca2.req.sha256
+	$(OPENSSL) x509 -req -in test-ca2.req.sha256 -extfile $< \
+		-signkey $(test_ca_key_file_ec) -days 3653 -out $@
+
+all_final += test-ca2.ku-crl.crt \
+			 test-ca2.ku-crt.crt \
+			 test-ca2.ku-crt_crl.crt \
+			 test-ca2.ku-ds.crt
+
 test-ca2-future.crt: $(test_ca_key_file_ec) test-ca2.req.sha256
 	$(MBEDTLS_CERT_WRITE) is_ca=1 serial=13926223505202072808 request_file=test-ca2.req.sha256 selfsign=1 \
 		issuer_name="C=NL,O=PolarSSL,CN=Polarssl Test EC CA" issuer_key=$(test_ca_key_file_ec) \
@@ -147,11 +162,15 @@
 all_final += $(test_ca_ec_cat)
 
 test-ca-any_policy.crt: $(test_ca_key_file_rsa) test-ca.req.sha256
-	$(OPENSSL) req -x509 -config $(test_ca_config_file) -extensions v3_any_policy_ca -key $(test_ca_key_file_rsa) -passin "pass:$(test_ca_pwd_rsa)" -set_serial 0 -days 3653 -sha256 -in test-ca.req.sha256 -out $@
+	$(OPENSSL) req -x509 -config $(test_ca_config_file) -extensions v3_any_policy_ca \
+		-key $(test_ca_key_file_rsa) -passin "pass:$(test_ca_pwd_rsa)" \
+		-set_serial 0 -days 3653 -sha256 -in test-ca.req.sha256 -out $@
 all_final += test-ca-any_policy.crt
 
 test-ca-any_policy_ec.crt: $(test_ca_key_file_ec) test-ca.req_ec.sha256
-	$(OPENSSL) req -x509 -config $(test_ca_config_file) -extensions v3_any_policy_ca -key $(test_ca_key_file_ec) -set_serial 0 -days 3653 -sha256 -in test-ca.req_ec.sha256 -out $@
+	$(OPENSSL) req -x509 -config $(test_ca_config_file) -extensions v3_any_policy_ca \
+		-key $(test_ca_key_file_ec) -set_serial 0 -days 3653 -sha256 \
+		-in test-ca.req_ec.sha256 -out $@
 all_final += test-ca-any_policy_ec.crt
 
 test-ca-any_policy_with_qualifier.crt: $(test_ca_key_file_rsa) test-ca.req.sha256
diff --git a/tests/data_files/test-ca2.ku-crl.crt b/tests/data_files/test-ca2.ku-crl.crt
index 4fb4083..303a2c0 100644
--- a/tests/data_files/test-ca2.ku-crl.crt
+++ b/tests/data_files/test-ca2.ku-crl.crt
@@ -1,12 +1,12 @@
 -----BEGIN CERTIFICATE-----
-MIIBzDCCAVOgAwIBAgIJAP6mZLzh0IPSMAoGCCqGSM49BAMCMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTAeFw0xNDA0MDkxMTIzMzhaFw0yNDA0MDYxMTIzMzhaMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTB2MBAGByqGSM49AgEGBSuBBAAiA2IABMPaKzRBN1gvh1b+/Im6KUNLTuBu
-ww5XUzM5WNRStJGVOQsj318XJGJI/BqVKc4sLYfCiFKAr9ZqqyHduNMcbli4yuiy
-aY7zQa0pw7RfdadHb9UZKVVpmlM7ILRmFmAzHqMdMBswDAYDVR0TBAUwAwEB/zAL
-BgNVHQ8EBAMCAQIwCgYIKoZIzj0EAwIDZwAwZAIwZOCKY0EHXYzI4cQsFnfOrxm1
-ufvNeZ4ZcSZWrkTBazW2OBCuCP9SLznec3SFOUvvAjAKe/qycfxkHivjieCEG1Kt
-m2D4QKSJELUhTHr4zdkeqbzgui0y3iouaoyWsKvetNg=
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+Vv78ibopQ0tO4G7DDldTMzlY1FK0kZU5CyPfXxckYkj8GpUpziwth8KIUoCv1mqr
+Id240xxuWLjK6LJpjvNBrSnDtF91p0dv1RkpVWmaUzsgtGYWYDMeox0wGzAMBgNV
+HRMEBTADAQH/MAsGA1UdDwQEAwIBAjAKBggqhkjOPQQDAgNoADBlAjAxoq/Q4PEA
+8SDd3cQaVIwx8oJVEzfJo1BB2w1LnjvUXZrQydjNXMU4Jgorm/2/uLgCMQCyI6cZ
+EAIgKPYlT6/zJHBj45qejs527OfI4Xn+kQ7OvHQtHaCAzQw4h7Jfx+gXaUo=
 -----END CERTIFICATE-----
diff --git a/tests/data_files/test-ca2.ku-crl.crt.openssl.v3_ext b/tests/data_files/test-ca2.ku-crl.crt.openssl.v3_ext
new file mode 100644
index 0000000..4bc5d3c
--- /dev/null
+++ b/tests/data_files/test-ca2.ku-crl.crt.openssl.v3_ext
@@ -0,0 +1,4 @@
+basicConstraints = CA:true
+subjectKeyIdentifier=none
+keyUsage = cRLSign
+
diff --git a/tests/data_files/test-ca2.ku-crt.crt b/tests/data_files/test-ca2.ku-crt.crt
index edacc64..5cad7b2 100644
--- a/tests/data_files/test-ca2.ku-crt.crt
+++ b/tests/data_files/test-ca2.ku-crt.crt
@@ -1,12 +1,12 @@
 -----BEGIN CERTIFICATE-----
-MIIBzTCCAVOgAwIBAgIJAODh6PAeD9/vMAoGCCqGSM49BAMCMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTAeFw0xNDA0MDkxMTIzNTRaFw0yNDA0MDYxMTIzNTRaMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTB2MBAGByqGSM49AgEGBSuBBAAiA2IABMPaKzRBN1gvh1b+/Im6KUNLTuBu
-ww5XUzM5WNRStJGVOQsj318XJGJI/BqVKc4sLYfCiFKAr9ZqqyHduNMcbli4yuiy
-aY7zQa0pw7RfdadHb9UZKVVpmlM7ILRmFmAzHqMdMBswDAYDVR0TBAUwAwEB/zAL
-BgNVHQ8EBAMCAgQwCgYIKoZIzj0EAwIDaAAwZQIwGGlbynd1jU3WkUx6Irhk9Lob
-z2B+1eIO6+eu3En8B3rh8Ipfxo0e0hpfaRFYP1MUAjEAjxxBchRWJAzZ6/47Wg/7
-UoasRINgP5B/uJhTnftS1bqyuWHastb4LW5/YLOvPbMQ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=
 -----END CERTIFICATE-----
diff --git a/tests/data_files/test-ca2.ku-crt.crt.openssl.v3_ext b/tests/data_files/test-ca2.ku-crt.crt.openssl.v3_ext
new file mode 100644
index 0000000..997c893
--- /dev/null
+++ b/tests/data_files/test-ca2.ku-crt.crt.openssl.v3_ext
@@ -0,0 +1,4 @@
+basicConstraints = CA:true
+subjectKeyIdentifier=none
+keyUsage = keyCertSign
+
diff --git a/tests/data_files/test-ca2.ku-crt_crl.crt b/tests/data_files/test-ca2.ku-crt_crl.crt
index ac74e40..4c69582 100644
--- a/tests/data_files/test-ca2.ku-crt_crl.crt
+++ b/tests/data_files/test-ca2.ku-crt_crl.crt
@@ -1,12 +1,12 @@
 -----BEGIN CERTIFICATE-----
-MIIBzDCCAVOgAwIBAgIJAPejOupCJS65MAoGCCqGSM49BAMCMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTAeFw0xNDA0MDkxMTIyMjVaFw0yNDA0MDYxMTIyMjVaMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTB2MBAGByqGSM49AgEGBSuBBAAiA2IABMPaKzRBN1gvh1b+/Im6KUNLTuBu
-ww5XUzM5WNRStJGVOQsj318XJGJI/BqVKc4sLYfCiFKAr9ZqqyHduNMcbli4yuiy
-aY7zQa0pw7RfdadHb9UZKVVpmlM7ILRmFmAzHqMdMBswDAYDVR0TBAUwAwEB/zAL
-BgNVHQ8EBAMCAQYwCgYIKoZIzj0EAwIDZwAwZAIwMKLVXB4YBQ0Ha4dEvFPcJtau
-TS5Vd4UqG3xQ10YcJogweuqaGHSFgdnEUfoX+4p5AjApMnYXFfUjSmlyfJmTaswO
-gaR5sUnnw33NA9j1ercem3asCYz6a8T0zo8/rR33XVU=
+MIIB2TCCAV6gAwIBAgIUd5f42F4ahjkx9AIN035pcF4WFikwCgYIKoZIzj0EAwIw
+PjELMAkGA1UEBhMCTkwxETAPBgNVBAoMCFBvbGFyU1NMMRwwGgYDVQQDDBNQb2xh
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+xknmJJ4H3Zlc+O5GlcX9VQNZDn1xV7hf2yW1Gf7wLTnSWTf5bXATaIQ6QLO1
 -----END CERTIFICATE-----
diff --git a/tests/data_files/test-ca2.ku-crt_crl.crt.openssl.v3_ext b/tests/data_files/test-ca2.ku-crt_crl.crt.openssl.v3_ext
new file mode 100644
index 0000000..0fd73a2
--- /dev/null
+++ b/tests/data_files/test-ca2.ku-crt_crl.crt.openssl.v3_ext
@@ -0,0 +1,4 @@
+basicConstraints = CA:true
+subjectKeyIdentifier=none
+keyUsage = keyCertSign, cRLSign
+
diff --git a/tests/data_files/test-ca2.ku-ds.crt b/tests/data_files/test-ca2.ku-ds.crt
index c28e17b..2907aa7 100644
--- a/tests/data_files/test-ca2.ku-ds.crt
+++ b/tests/data_files/test-ca2.ku-ds.crt
@@ -1,12 +1,12 @@
 -----BEGIN CERTIFICATE-----
-MIIBzDCCAVOgAwIBAgIJAPOkPR3wsvm5MAoGCCqGSM49BAMCMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTAeFw0xNDA0MDkxMTI0MTNaFw0yNDA0MDYxMTI0MTNaMD4xCzAJBgNVBAYT
-Ak5MMREwDwYDVQQKEwhQb2xhclNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBF
-QyBDQTB2MBAGByqGSM49AgEGBSuBBAAiA2IABMPaKzRBN1gvh1b+/Im6KUNLTuBu
-ww5XUzM5WNRStJGVOQsj318XJGJI/BqVKc4sLYfCiFKAr9ZqqyHduNMcbli4yuiy
-aY7zQa0pw7RfdadHb9UZKVVpmlM7ILRmFmAzHqMdMBswDAYDVR0TBAUwAwEB/zAL
-BgNVHQ8EBAMCB4AwCgYIKoZIzj0EAwIDZwAwZAIwGRCmU/rWNjW13g8ITuq3pMXb
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-nQdac59ev+lH+ju6wET3jNDjUthUPrdgqa54+UWQ5r4=
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+xdmEPUr6PY54c0IQJNeeF76L1/+EszXrSDQ7TLv1YC4d4uMNmqwR9EGuUX+/
 -----END CERTIFICATE-----
diff --git a/tests/data_files/test-ca2.ku-ds.crt.openssl.v3_ext b/tests/data_files/test-ca2.ku-ds.crt.openssl.v3_ext
new file mode 100644
index 0000000..08e49d4
--- /dev/null
+++ b/tests/data_files/test-ca2.ku-ds.crt.openssl.v3_ext
@@ -0,0 +1,4 @@
+basicConstraints = CA:true
+subjectKeyIdentifier=none
+keyUsage = digitalSignature
+