diff --git a/pkg/controller/certificates/BUILD b/pkg/controller/certificates/BUILD
index 95d8ec20a67..3b661ba9971 100644
--- a/pkg/controller/certificates/BUILD
+++ b/pkg/controller/certificates/BUILD
@@ -5,6 +5,7 @@ licenses(["notice"])
 load(
     "@io_bazel_rules_go//go:def.bzl",
     "go_library",
+    "go_test",
 )
 
 go_library(
@@ -52,3 +53,19 @@ filegroup(
     srcs = [":package-srcs"],
     tags = ["automanaged"],
 )
+
+go_test(
+    name = "go_default_test",
+    srcs = ["cfssl_signer_test.go"],
+    data = [
+        "testdata/ca.crt",
+        "testdata/ca.key",
+        "testdata/kubelet.csr",
+    ],
+    library = ":go_default_library",
+    tags = ["automanaged"],
+    deps = [
+        "//pkg/apis/certificates/v1alpha1:go_default_library",
+        "//pkg/util/cert:go_default_library",
+    ],
+)
diff --git a/pkg/controller/certificates/cfssl_signer_test.go b/pkg/controller/certificates/cfssl_signer_test.go
new file mode 100644
index 00000000000..3abd425cb4f
--- /dev/null
+++ b/pkg/controller/certificates/cfssl_signer_test.go
@@ -0,0 +1,82 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package certificates
+
+import (
+	"crypto/x509"
+	"io/ioutil"
+	"reflect"
+	"testing"
+
+	capi "k8s.io/kubernetes/pkg/apis/certificates/v1alpha1"
+	"k8s.io/kubernetes/pkg/util/cert"
+)
+
+func TestSigner(t *testing.T) {
+	s, err := NewCFSSLSigner("./testdata/ca.crt", "./testdata/ca.key")
+	if err != nil {
+		t.Fatalf("failed to create signer: %v", err)
+	}
+
+	csrb, err := ioutil.ReadFile("./testdata/kubelet.csr")
+	if err != nil {
+		t.Fatalf("failed to read CSR: %v", err)
+	}
+
+	csr := &capi.CertificateSigningRequest{
+		Spec: capi.CertificateSigningRequestSpec{
+			Request: []byte(csrb),
+			Usages: []capi.KeyUsage{
+				capi.UsageSigning,
+				capi.UsageKeyEncipherment,
+				capi.UsageServerAuth,
+				capi.UsageClientAuth,
+			},
+		},
+	}
+
+	certData, err := s.Sign(csr)
+	if err != nil {
+		t.Fatalf("failed to sign CSR: %v", err)
+	}
+	if len(certData) == 0 {
+		t.Fatalf("expected a certificate after signing")
+	}
+
+	certs, err := cert.ParseCertsPEM(certData)
+	if err != nil {
+		t.Fatalf("failed to parse certificate: %v", err)
+	}
+	if len(certs) != 1 {
+		t.Fatalf("expected one certificate")
+	}
+
+	crt := certs[0]
+
+	if crt.Subject.CommonName != "system:node:k-a-node-s36b" {
+		t.Errorf("expected common name of 'system:node:k-a-node-s36b', but got: %v", certs[0].Subject.CommonName)
+	}
+	if !reflect.DeepEqual(crt.Subject.Organization, []string{"system:nodes"}) {
+		t.Errorf("expected organization to be [system:nodes] but got: %v", crt.Subject.Organization)
+	}
+	if crt.KeyUsage != x509.KeyUsageDigitalSignature|x509.KeyUsageKeyEncipherment {
+		t.Errorf("bad key usage")
+	}
+	if !reflect.DeepEqual(crt.ExtKeyUsage, []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth, x509.ExtKeyUsageClientAuth}) {
+		t.Errorf("bad extended key usage")
+	}
+}
diff --git a/pkg/controller/certificates/testdata/ca.crt b/pkg/controller/certificates/testdata/ca.crt
new file mode 100644
index 00000000000..419f970016b
--- /dev/null
+++ b/pkg/controller/certificates/testdata/ca.crt
@@ -0,0 +1,18 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/pkg/controller/certificates/testdata/ca.key b/pkg/controller/certificates/testdata/ca.key
new file mode 100644
index 00000000000..fdf489609a8
--- /dev/null
+++ b/pkg/controller/certificates/testdata/ca.key
@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
diff --git a/pkg/controller/certificates/testdata/kubelet.csr b/pkg/controller/certificates/testdata/kubelet.csr
new file mode 100644
index 00000000000..1153a0435d0
--- /dev/null
+++ b/pkg/controller/certificates/testdata/kubelet.csr
@@ -0,0 +1,8 @@
+-----BEGIN CERTIFICATE REQUEST-----
+MIH1MIGdAgEAMDsxFTATBgNVBAoTDHN5c3RlbTpub2RlczEiMCAGA1UEAxMZc3lz
+dGVtOm5vZGU6ay1hLW5vZGUtczM2YjBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IA
+BJbxa5Y8SrUJVHpOoWD5ceqH+5R9mjIhwVP2sqfTcLkjvbitzOiLlxSq/LwJ+qq7
+kVpf9f3GopZVhRWbYSCg0YGgADAKBggqhkjOPQQDAgNHADBEAiAabb6XFtPOJUCQ
++84NhxLEvPANhrtwFq3Q0qFZ9TzH5QIgc/697RTTcbri2lVj+10dLFIC3VYJ7br4
+QjA7haCYXrA=
+-----END CERTIFICATE REQUEST-----