Read signature algorithm from key

1 files changed, 23 insertions, 0 deletions

diff --git a/security-utils/src/main/java/com/yahoo/security/SignatureUtils.java b/security-utils/src/main/java/com/yahoo/security/SignatureUtils.java
index 7560fbbd40d..13bc140d797 100644
--- a/security-utils/src/main/java/com/yahoo/security/SignatureUtils.java
+++ b/security-utils/src/main/java/com/yahoo/security/SignatureUtils.java
@@ -2,6 +2,7 @@
 package com.yahoo.security;
 
 import java.security.GeneralSecurityException;
+import java.security.Key;
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.Signature;
@@ -24,6 +25,11 @@ public class SignatureUtils {
         }
     }
 
+    /** Returns a signature instance which computes a hash of its content, before signing with the given private key. */
+    public static Signature createSigner(PrivateKey key) {
+        return createSigner(key, getSignatureAlgorithm(key));
+    }
+
     /** Returns a signature instance which computes a hash of its content, before verifying with the given public key. */
     public static Signature createVerifier(PublicKey key, SignatureAlgorithm algorithm) {
         try {
@@ -34,4 +40,21 @@ public class SignatureUtils {
             throw new IllegalStateException(e);
         }
     }
+
+    /** Returns a signature instance which computes a hash of its content, before verifying with the given public key. */
+    public static Signature createVerifier(PublicKey key) {
+        return createVerifier(key, getSignatureAlgorithm(key));
+    }
+
+    /* Returns a signature algorithm supported by the key based on SHA512 */
+    private static SignatureAlgorithm getSignatureAlgorithm(Key key) {
+        switch (key.getAlgorithm()) {
+            case "EC":
+                return SignatureAlgorithm.SHA512_WITH_ECDSA;
+            case "RSA":
+                return SignatureAlgorithm.SHA512_WITH_RSA;
+            default:
+                throw new RuntimeException("Unknown Key algorithm " + key.getAlgorithm());
+        }
+    }
 }