1 files changed, 95 insertions, 0 deletions
diff --git a/pg/src/main/java/org/spongycastle/openpgp/operator/bc/BcPBEKeyEncryptionMethodGenerator.java b/pg/src/main/java/org/spongycastle/openpgp/operator/bc/BcPBEKeyEncryptionMethodGenerator.java
new file mode 100644
index 00000000..2a151f0d
--- /dev/null
+++ b/pg/src/main/java/org/spongycastle/openpgp/operator/bc/BcPBEKeyEncryptionMethodGenerator.java
@@ -0,0 +1,95 @@
+package org.spongycastle.openpgp.operator.bc;
+
+import java.security.SecureRandom;
+
+import org.spongycastle.bcpg.S2K;
+import org.spongycastle.crypto.BlockCipher;
+import org.spongycastle.crypto.BufferedBlockCipher;
+import org.spongycastle.crypto.InvalidCipherTextException;
+import org.spongycastle.openpgp.PGPException;
+import org.spongycastle.openpgp.operator.PBEKeyEncryptionMethodGenerator;
+import org.spongycastle.openpgp.operator.PGPDigestCalculator;
+
+/**
+ * A BC lightweight method generator for supporting PBE based encryption operations.
+ */
+public class BcPBEKeyEncryptionMethodGenerator
+    extends PBEKeyEncryptionMethodGenerator
+{
+    /**
+     * Create a PBE encryption method generator using the provided digest and the default S2K count
+     * for key generation.
+     *
+     * @param passPhrase the passphrase to use as the primary source of key material.
+     * @param s2kDigestCalculator the digest calculator to use for key calculation.
+     */
+    public BcPBEKeyEncryptionMethodGenerator(char[] passPhrase, PGPDigestCalculator s2kDigestCalculator)
+    {
+        super(passPhrase, s2kDigestCalculator);
+    }
+
+    /**
+     * Create a PBE encryption method generator using the default SHA-1 digest and the default S2K
+     * count for key generation.
+     *
+     * @param passPhrase the passphrase to use as the primary source of key material.
+     */
+    public BcPBEKeyEncryptionMethodGenerator(char[] passPhrase)
+    {
+        this(passPhrase, new SHA1PGPDigestCalculator());
+    }
+
+    /**
+     * Create a PBE encryption method generator using the provided calculator and S2K count for key
+     * generation.
+     * 
+     * @param passPhrase the passphrase to use as the primary source of key material.
+     * @param s2kDigestCalculator the digest calculator to use for key calculation.
+     * @param s2kCount the single byte {@link S2K} count to use.
+     */
+    public BcPBEKeyEncryptionMethodGenerator(char[] passPhrase, PGPDigestCalculator s2kDigestCalculator, int s2kCount)
+    {
+        super(passPhrase, s2kDigestCalculator, s2kCount);
+    }
+
+    /**
+     * Create a PBE encryption method generator using the default SHA-1 digest calculator and a S2K
+     * count other than the default for key generation.
+     *
+     * @param passPhrase the passphrase to use as the primary source of key material.
+     * @param s2kCount the single byte {@link S2K} count to use.
+     */
+    public BcPBEKeyEncryptionMethodGenerator(char[] passPhrase, int s2kCount)
+    {
+        super(passPhrase, new SHA1PGPDigestCalculator(), s2kCount);
+    }
+
+    public PBEKeyEncryptionMethodGenerator setSecureRandom(SecureRandom random)
+    {
+        super.setSecureRandom(random);
+
+        return this;
+    }
+
+    protected byte[] encryptSessionInfo(int encAlgorithm, byte[] key, byte[] sessionInfo)
+        throws PGPException
+    {
+        try
+        {
+            BlockCipher engine = BcImplProvider.createBlockCipher(encAlgorithm);
+            BufferedBlockCipher cipher = BcUtil.createSymmetricKeyWrapper(true, engine, key, new byte[engine.getBlockSize()]);
+
+            byte[] out = new byte[sessionInfo.length];
+
+            int len = cipher.processBytes(sessionInfo, 0, sessionInfo.length, out, 0);
+
+            len += cipher.doFinal(out, len);
+
+            return out;
+        }
+        catch (InvalidCipherTextException e)
+        {
+            throw new PGPException("encryption failed: " + e.getMessage(), e);
+        }
+    }
+}