Remove PublicKeyKeyEncryptionMethodGenerator.concatECDHEphKeyWithWrappedSessionKey method

Author: gefeili

pg/src/main/java/org/bouncycastle/openpgp/operator/PublicKeyKeyEncryptionMethodGenerator.java

@@ -221,41 +221,21 @@ protected abstract byte[] encryptSessionInfo(PGPPublicKey pubKey,
                                                  byte optSymAlgId)
         throws PGPException;
 
-
-    protected static byte[] concatECDHEphKeyWithWrappedSessionKey(byte[] ephPubEncoding, byte[] wrappedSessionKey)
-        throws IOException
-    {
-        // https://www.rfc-editor.org/rfc/rfc9580.html#section-11.5-16
-
-        byte[] mpiEncodedEphemeralKey = new MPInteger(new BigInteger(1, ephPubEncoding))
-            .getEncoded();
-        byte[] out = new byte[mpiEncodedEphemeralKey.length + 1 + wrappedSessionKey.length];
-        // eph key
-        System.arraycopy(mpiEncodedEphemeralKey, 0, out, 0, mpiEncodedEphemeralKey.length);
-        // enc session-key len
-        out[mpiEncodedEphemeralKey.length] = (byte)wrappedSessionKey.length;
-        // enc session-key
-        System.arraycopy(wrappedSessionKey, 0, out, mpiEncodedEphemeralKey.length + 1, wrappedSessionKey.length);
-
-        return out;
-    }
-
     protected static byte[] getSessionInfo(byte[] ephPubEncoding, byte optSymKeyAlgorithm, byte[] wrappedSessionKey)
     {
-        int len = ephPubEncoding.length  + wrappedSessionKey.length + (optSymKeyAlgorithm != 0 ? 2 : 1);
+        int len = ephPubEncoding.length + wrappedSessionKey.length + (optSymKeyAlgorithm != 0 ? 2 : 1);
         byte[] out = new byte[len];
         // ephemeral pub key
         System.arraycopy(ephPubEncoding, 0, out, 0, ephPubEncoding.length);
         // len of two/one next fields
-        out[ephPubEncoding.length] = (byte)(wrappedSessionKey.length + 1);
+        out[ephPubEncoding.length] = (byte)(wrappedSessionKey.length + (optSymKeyAlgorithm != 0 ? 1 : 0));
         // (optional) sym key alg
         if (optSymKeyAlgorithm != 0)
         {
             out[ephPubEncoding.length + 1] = optSymKeyAlgorithm;
         }
         // wrapped session key
         System.arraycopy(wrappedSessionKey, 0, out, len - wrappedSessionKey.length, wrappedSessionKey.length);
-
         return out;
     }
 }

pg/src/main/java/org/bouncycastle/openpgp/operator/bc/BcPublicKeyKeyEncryptionMethodGenerator.java

@@ -7,6 +7,7 @@
 import org.bouncycastle.asn1.edec.EdECObjectIdentifiers;
 import org.bouncycastle.bcpg.ECDHPublicBCPGKey;
 import org.bouncycastle.bcpg.HashAlgorithmTags;
+import org.bouncycastle.bcpg.MPInteger;
 import org.bouncycastle.bcpg.PublicKeyAlgorithmTags;
 import org.bouncycastle.bcpg.PublicKeyPacket;
 import org.bouncycastle.bcpg.SymmetricKeyAlgorithmTags;
@@ -217,7 +218,9 @@ private byte[] encryptSessionInfoWithECDHKey(byte[] sessionInfo,
         byte[] paddedSessionData = PGPPad.padSessionData(sessionInfo, sessionKeyObfuscation);
 
         // wrap the padded session info using the shared-secret public key
-        return concatECDHEphKeyWithWrappedSessionKey(ephPubEncoding, getWrapper(symmetricKeyAlgorithm, key, paddedSessionData));
+        // https://www.rfc-editor.org/rfc/rfc9580.html#section-11.5-16
+        return getSessionInfo(new MPInteger(new BigInteger(1, ephPubEncoding))
+            .getEncoded(), (byte)0, getWrapper(symmetricKeyAlgorithm, key, paddedSessionData));
     }
 
     private byte[] encryptSessionInfoWithX25519X448Key(PublicKeyPacket pubKeyPacket,

pg/src/main/java/org/bouncycastle/openpgp/operator/jcajce/JcePublicKeyKeyEncryptionMethodGenerator.java

@@ -1,6 +1,7 @@
 package org.bouncycastle.openpgp.operator.jcajce;
 
 import java.io.IOException;
+import java.math.BigInteger;
 import java.security.AlgorithmParameters;
 import java.security.GeneralSecurityException;
 import java.security.InvalidKeyException;
@@ -22,6 +23,7 @@
 import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
 import org.bouncycastle.asn1.x9.X962Parameters;
 import org.bouncycastle.bcpg.ECDHPublicBCPGKey;
+import org.bouncycastle.bcpg.MPInteger;
 import org.bouncycastle.bcpg.PublicKeyAlgorithmTags;
 import org.bouncycastle.bcpg.PublicKeyPacket;
 import org.bouncycastle.bcpg.SymmetricKeyAlgorithmTags;
@@ -261,7 +263,9 @@ private byte[] encryptSessionInfoWithECDHKey(PublicKeyPacket pubKeyPacket, Strin
         byte[] paddedSessionData = PGPPad.padSessionData(sessionInfo, sessionKeyObfuscation);
 
         // wrap the padded session info using the shared-secret public key
-        return concatECDHEphKeyWithWrappedSessionKey(ephPubEncoding, getWrapper(symmetricKeyAlgorithm, sessionInfo, secret, paddedSessionData));
+        // https://www.rfc-editor.org/rfc/rfc9580.html#section-11.5-16
+        return  getSessionInfo(new MPInteger(new BigInteger(1, ephPubEncoding))
+            .getEncoded(), (byte)0, getWrapper(symmetricKeyAlgorithm, sessionInfo, secret, paddedSessionData));
     }
 
     /**