Refactor on IssuerKeyID, bcpg.sig.Utils. Add comments to PGPKeyEncryp…

…tionMethodGenerator, make iv in SecretKeyPacket is copied when processing. Refactor on SExpression.

pg/src/main/java/org/bouncycastle/bcpg/SecretKeyPacket.java

@@ -3,6 +3,7 @@
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 
+import org.bouncycastle.util.Arrays;
 import org.bouncycastle.util.io.Streams;
 
 /**
@@ -208,7 +209,7 @@ public SecretKeyPacket(
         this.aeadAlgorithm = aeadAlgorithm;
         this.s2kUsage = s2kUsage;
         this.s2k = s2k;
-        this.iv = iv;
+        this.iv = Arrays.clone(iv);
         this.secKeyData = secKeyData;
 
         if (s2k != null && s2k.getType() == S2K.ARGON_2 && s2kUsage != USAGE_AEAD)
@@ -242,7 +243,7 @@ public int getS2KUsage()
 
     public byte[] getIV()
     {
-        return iv;
+        return Arrays.clone(iv);
     }
 
     public S2K getS2K()

pg/src/main/java/org/bouncycastle/bcpg/sig/IssuerKeyID.java

@@ -2,6 +2,7 @@
 
 import org.bouncycastle.bcpg.SignatureSubpacket;
 import org.bouncycastle.bcpg.SignatureSubpacketTags;
+import org.bouncycastle.util.Pack;
 
 /**
  * packet giving the issuer key ID.
@@ -12,18 +13,7 @@ public class IssuerKeyID
     protected static byte[] keyIDToBytes(
         long    keyId)
     {
-        byte[]    data = new byte[8];
-
-        data[0] = (byte)(keyId >> 56);
-        data[1] = (byte)(keyId >> 48);
-        data[2] = (byte)(keyId >> 40);
-        data[3] = (byte)(keyId >> 32);
-        data[4] = (byte)(keyId >> 24);
-        data[5] = (byte)(keyId >> 16);
-        data[6] = (byte)(keyId >> 8);
-        data[7] = (byte)keyId;
-
-        return data;
+        return Pack.longToBigEndian(keyId);
     }
 
     public IssuerKeyID(
@@ -43,9 +33,6 @@ public IssuerKeyID(
 
     public long getKeyID()
     {
-        long    keyID = ((long)(data[0] & 0xff) << 56) | ((long)(data[1] & 0xff) << 48) | ((long)(data[2] & 0xff) << 40) | ((long)(data[3] & 0xff) << 32)
-                                | ((long)(data[4] & 0xff) << 24) | ((data[5] & 0xff) << 16) | ((data[6] & 0xff) << 8) | (data[7] & 0xff);
-
-        return keyID;
+        return Pack.bigEndianToLong(data, 0);
     }
 }

pg/src/main/java/org/bouncycastle/bcpg/sig/Utils.java

@@ -1,5 +1,7 @@
 package org.bouncycastle.bcpg.sig;
 
+import org.bouncycastle.util.Pack;
+
 class Utils
 {
     /**
@@ -55,19 +57,11 @@ static long timeFromBytes(byte[] bytes)
             throw new IllegalStateException("Byte array has unexpected length. Expected length 4, got " + bytes.length);
         }
 
-        return ((long)(bytes[0] & 0xff) << 24)
-            |  ((bytes[1] & 0xff) << 16)
-            |  ((bytes[2] & 0xff) << 8)
-            |   (bytes[3] & 0xff);
+        return Pack.bigEndianToInt(bytes, 0);
     }
 
     static byte[] timeToBytes(long t)
     {
-        byte[] data = new byte[4];
-        data[0] = (byte)(t >> 24);
-        data[1] = (byte)(t >> 16);
-        data[2] = (byte)(t >> 8);
-        data[3] = (byte)t;
-        return data;
+        return Pack.intToBigEndian((int)t);
     }
 }

pg/src/main/java/org/bouncycastle/gpg/SExpression.java

@@ -165,7 +165,7 @@ private static SExpression parseExpression(InputStream src, SExpression expr, By
                 else if (c == '#')
                 {
                     consumeUntilSkipWhiteSpace(src, accumulator, '#');
-                    expr.addValue(Hex.decode(Strings.fromByteArray(accumulator.toByteArray())));
+                    expr.addValue(Hex.decode(accumulator.toByteArray()));
                 }
                 else if (c == '"')
                 {

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

@@ -1,6 +1,7 @@
 package org.bouncycastle.openpgp.operator;
 
 import org.bouncycastle.bcpg.ContainedPacket;
+import org.bouncycastle.bcpg.SymmetricKeyAlgorithmTags;
 import org.bouncycastle.openpgp.PGPEncryptedDataGenerator;
 import org.bouncycastle.openpgp.PGPException;
 
@@ -9,6 +10,14 @@
  */
 public abstract class PGPKeyEncryptionMethodGenerator
 {
+    /**
+     * Generates a packet encoding the details of this encryption method.
+     *
+     * @param encAlgorithm the {@link SymmetricKeyAlgorithmTags encryption algorithm} being used
+     * @param sessionInfo session data generated by the encrypted data generator.
+     * @return a packet encoding the provided information and the configuration of this instance.
+     * @throws PGPException if an error occurs constructing the packet.
+     */
     public abstract ContainedPacket generate(int encAlgorithm, byte[] sessionInfo)
         throws PGPException;