1 files changed, 118 insertions, 0 deletions
diff --git a/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/operator/bc/BcPGPDataEncryptorBuilder.java b/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/operator/bc/BcPGPDataEncryptorBuilder.java
new file mode 100644
index 000000000..5c65ce499
--- /dev/null
+++ b/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/operator/bc/BcPGPDataEncryptorBuilder.java
@@ -0,0 +1,118 @@
+package org.spongycastle.openpgp.operator.bc;
+
+import java.io.OutputStream;
+import java.security.SecureRandom;
+
+import org.spongycastle.crypto.BlockCipher;
+import org.spongycastle.crypto.BufferedBlockCipher;
+import org.spongycastle.crypto.io.CipherOutputStream;
+import org.spongycastle.openpgp.PGPException;
+import org.spongycastle.openpgp.operator.PGPDataEncryptor;
+import org.spongycastle.openpgp.operator.PGPDataEncryptorBuilder;
+import org.spongycastle.openpgp.operator.PGPDigestCalculator;
+
+public class BcPGPDataEncryptorBuilder
+    implements PGPDataEncryptorBuilder
+{
+    private SecureRandom   random;
+    private boolean withIntegrityPacket;
+    private int encAlgorithm;
+
+    public BcPGPDataEncryptorBuilder(int encAlgorithm)
+    {
+        this.encAlgorithm = encAlgorithm;
+
+        if (encAlgorithm == 0)
+        {
+            throw new IllegalArgumentException("null cipher specified");
+        }
+    }
+
+   /**
+     * Determine whether or not the resulting encrypted data will be protected using an integrity packet.
+     *
+     * @param withIntegrityPacket true if an integrity packet is to be included, false otherwise.
+     * @return  the current builder.
+     */
+    public BcPGPDataEncryptorBuilder setWithIntegrityPacket(boolean withIntegrityPacket)
+    {
+        this.withIntegrityPacket = withIntegrityPacket;
+
+        return this;
+    }
+
+    /**
+     * Provide a user defined source of randomness.
+     *
+     * @param random  the secure random to be used.
+     * @return  the current builder.
+     */
+    public BcPGPDataEncryptorBuilder setSecureRandom(SecureRandom random)
+    {
+        this.random = random;
+
+        return this;
+    }
+
+    public int getAlgorithm()
+    {
+        return encAlgorithm;
+    }
+
+    public SecureRandom getSecureRandom()
+    {
+        if (random == null)
+        {
+            random = new SecureRandom();
+        }
+
+        return random;
+    }
+
+    public PGPDataEncryptor build(byte[] keyBytes)
+        throws PGPException
+    {
+        return new MyPGPDataEncryptor(keyBytes);
+    }
+
+    private class MyPGPDataEncryptor
+        implements PGPDataEncryptor
+    {
+        private final BufferedBlockCipher c;
+
+        MyPGPDataEncryptor(byte[] keyBytes)
+            throws PGPException
+        {
+            BlockCipher engine = BcImplProvider.createBlockCipher(encAlgorithm);
+
+            try
+            {
+                c = BcUtil.createStreamCipher(true, engine, withIntegrityPacket, keyBytes);
+            }
+            catch (IllegalArgumentException e)
+            {
+                throw new PGPException("invalid parameters: " + e.getMessage(), e);
+            }
+        }
+
+        public OutputStream getOutputStream(OutputStream out)
+        {
+            return new CipherOutputStream(out, c);
+        }
+
+        public PGPDigestCalculator getIntegrityCalculator()
+        {
+            if (withIntegrityPacket)
+            {
+                return new SHA1PGPDigestCalculator();
+            }
+
+            return null;
+        }
+
+        public int getBlockSize()
+        {
+            return c.getBlockSize();
+        }
+    }
+}