Add support for parsing public keys to KeyUtils

2 files changed, 65 insertions, 1 deletions

diff --git a/security-utils/src/main/java/com/yahoo/security/KeyUtils.java b/security-utils/src/main/java/com/yahoo/security/KeyUtils.java
index ca99598c1fb..47f625641e1 100644
--- a/security-utils/src/main/java/com/yahoo/security/KeyUtils.java
+++ b/security-utils/src/main/java/com/yahoo/security/KeyUtils.java
@@ -4,6 +4,7 @@ package com.yahoo.security;
 import org.bouncycastle.asn1.ASN1Encodable;
 import org.bouncycastle.asn1.ASN1Primitive;
 import org.bouncycastle.asn1.pkcs.PrivateKeyInfo;
+import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
 import org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPrivateKey;
 import org.bouncycastle.jce.spec.ECParameterSpec;
 import org.bouncycastle.jce.spec.ECPublicKeySpec;
@@ -26,8 +27,10 @@ import java.security.KeyPairGenerator;
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.interfaces.RSAPrivateCrtKey;
+import java.security.spec.KeySpec;
 import java.security.spec.PKCS8EncodedKeySpec;
 import java.security.spec.RSAPublicKeySpec;
+import java.security.spec.X509EncodedKeySpec;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -109,6 +112,30 @@ public class KeyUtils {
         }
     }
 
+    public static PublicKey fromPemEncodedPublicKey(String pem) {
+        try (PEMParser parser = new PEMParser(new StringReader(pem))) {
+            List<Object> unknownObjects = new ArrayList<>();
+            Object pemObject;
+            while ((pemObject = parser.readObject()) != null) {
+                SubjectPublicKeyInfo keyInfo;
+                if (pemObject instanceof SubjectPublicKeyInfo) {
+                    keyInfo = (SubjectPublicKeyInfo) pemObject;
+                } else if (pemObject instanceof PEMKeyPair) {
+                    PEMKeyPair pemKeypair = (PEMKeyPair) pemObject;
+                    keyInfo = pemKeypair.getPublicKeyInfo();
+                } else {
+                    unknownObjects.add(pemObject);
+                    continue;
+                }
+                JcaPEMKeyConverter pemConverter = new JcaPEMKeyConverter().setProvider(BouncyCastleProviderHolder.getInstance());
+                return pemConverter.getPublicKey(keyInfo);
+            }
+            throw new IllegalArgumentException("Expected a public key, but found " + unknownObjects.toString());
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+
     public static String toPem(PrivateKey privateKey) {
         try (StringWriter stringWriter = new StringWriter(); JcaPEMWriter pemWriter = new JcaPEMWriter(stringWriter)) {
             String algorithm = privateKey.getAlgorithm();
diff --git a/security-utils/src/test/java/com/yahoo/security/KeyUtilsTest.java b/security-utils/src/test/java/com/yahoo/security/KeyUtilsTest.java
index 5e786654d7c..6097f075f25 100644
--- a/security-utils/src/test/java/com/yahoo/security/KeyUtilsTest.java
+++ b/security-utils/src/test/java/com/yahoo/security/KeyUtilsTest.java
@@ -17,6 +17,32 @@ import static org.junit.Assert.assertThat;
  */
 public class KeyUtilsTest {
 
+    private static final String rsaPemPublicKey = "-----BEGIN PUBLIC KEY-----\n" +
+                                                 "MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAsKL8jvIEy2peLtEvyhWW\n" +
+                                                 "b/O/9RHTfPXjeXahXmVrXE4zY5CJ6Mf1PFkwQ8K8S35YhSbOZM4aYhF9V8F4jwyW\n" +
+                                                 "nX6qWUMrWVHOuS32fkjdNo0z/KxCbG5nRIWLuv/PkHNuIJqMCbwn6Qud5a+wxeLg\n" +
+                                                 "LqlroCtUJKAGj4YlZ5i8oMdCqfHKl/DMwcks5XxtIArz6GcM2z8fOB3NRexj32MU\n" +
+                                                 "LH7ybWhCDx/RSqGQYJ8sWEFIK4HSmYqwqIQpFAm/ixISkeWBL6ikgqchZNMf7xyn\n" +
+                                                 "yJxjCHgtkxANsQhHj2kgAzLDeBsuM+/WRhBGa+LRvEcuu/zZv9+7eVhpaYJveLVd\n" +
+                                                 "cwPewW/8liBmKIzj/QPCn7ZlVRk094TZD6TCER4+JFW9mo0vFD8S9o0zhMlckzCF\n" +
+                                                 "4ZNNgyP9tI8Wecq25A+sUY5/WZNLi+mka/GnfPt97GrhM0YHb1M6t4nh1R437Nwh\n" +
+                                                 "rUHR/YDazbBvLk5T71GgfQfn44L9SwsqEYaHvdZAfV0IZJBtDo/yCe/yvgtHTymB\n" +
+                                                 "eBrRMpBU5recPtW8bgEWlHl6Qyduw9EBJjNYxvBpgV/D/tNBcau0aGxmhwpBevet\n" +
+                                                 "ekV6XA2miC7rWu2Wrq2l5LjXEgZOD5PNN2vQS2Cdet9JHYWbVbK3mBLgoChcC5Xo\n" +
+                                                 "/QHLU4RydI0i0+Z2/tjGsGsCAwEAAQ==\n" +
+                                                 "-----END PUBLIC KEY-----\n";
+
+    private static final String ecPemPublicKey = "-----BEGIN PUBLIC KEY-----\n" +
+                                                "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEuKVFA8dXk43kVfYKzkUqhEY2rDT9\n" +
+                                                "z/4jKSTHwbYR8wdsOSrJGVEUPbS2nguIJ64OJH7gFnxM6sxUVj+Nm2HlXw==\n" +
+                                                "-----END PUBLIC KEY-----\n";
+
+    private static final String ecPemPrivateKey = "-----BEGIN EC PRIVATE KEY-----\n" +
+                                                  "MHcCAQEEIJUmbIX8YFLHtpRgkwqDDE3igU9RG6JD9cYHWAZii9j7oAoGCCqGSM49\n" +
+                                                  "AwEHoUQDQgAEuKVFA8dXk43kVfYKzkUqhEY2rDT9z/4jKSTHwbYR8wdsOSrJGVEU\n" +
+                                                  "PbS2nguIJ64OJH7gFnxM6sxUVj+Nm2HlXw==\n" +
+                                                  "-----END EC PRIVATE KEY-----\n";
+
     @Test
     public void can_extract_public_key_from_rsa_private() {
         KeyPair keyPair = KeyUtils.generateKeypair(KeyAlgorithm.RSA);
@@ -51,4 +77,15 @@ public class KeyUtilsTest {
         assertEquals(keyPair.getPrivate(), deserializedKey);
     }
 
-}
\ No newline at end of file
+    @Test
+    public void can_deserialize_rsa_publickey_in_pem_format() {
+        KeyUtils.fromPemEncodedPublicKey(rsaPemPublicKey);
+    }
+
+    @Test
+    public void can_deserialize_ec_keys_in_pem_format() {
+        KeyUtils.fromPemEncodedPublicKey(ecPemPublicKey);
+        KeyUtils.fromPemEncodedPrivateKey(ecPemPrivateKey);
+    }
+
+}