1 files changed, 104 insertions, 0 deletions
diff --git a/pg/src/main/java/org/spongycastle/openpgp/operator/PBESecretKeyEncryptor.java b/pg/src/main/java/org/spongycastle/openpgp/operator/PBESecretKeyEncryptor.java
new file mode 100644
index 00000000..2bd1bf8f
--- /dev/null
+++ b/pg/src/main/java/org/spongycastle/openpgp/operator/PBESecretKeyEncryptor.java
@@ -0,0 +1,104 @@
+package org.spongycastle.openpgp.operator;
+
+import java.security.SecureRandom;
+
+import org.spongycastle.bcpg.S2K;
+import org.spongycastle.openpgp.PGPException;
+
+public abstract class PBESecretKeyEncryptor
+{
+    protected int encAlgorithm;
+    protected char[] passPhrase;
+    protected PGPDigestCalculator s2kDigestCalculator;
+    protected int s2kCount;
+    protected S2K s2k;
+
+    protected SecureRandom random;
+
+    protected PBESecretKeyEncryptor(int encAlgorithm, PGPDigestCalculator s2kDigestCalculator, SecureRandom random, char[] passPhrase)
+    {
+        this(encAlgorithm, s2kDigestCalculator, 0x60, random, passPhrase);
+    }
+
+    protected PBESecretKeyEncryptor(int encAlgorithm, PGPDigestCalculator s2kDigestCalculator, int s2kCount, SecureRandom random, char[] passPhrase)
+    {
+        this.encAlgorithm = encAlgorithm;
+        this.passPhrase = passPhrase;
+        this.random = random;
+        this.s2kDigestCalculator = s2kDigestCalculator;
+
+        if (s2kCount < 0 || s2kCount > 0xff)
+        {
+            throw new IllegalArgumentException("s2kCount value outside of range 0 to 255.");
+        }
+
+        this.s2kCount = s2kCount;
+    }
+
+    public int getAlgorithm()
+    {
+        return encAlgorithm;
+    }
+
+    public int getHashAlgorithm()
+    {
+        if (s2kDigestCalculator != null)
+        {
+            return s2kDigestCalculator.getAlgorithm();
+        }
+
+        return -1;
+    }
+
+    public byte[] getKey()
+        throws PGPException
+    {
+        return PGPUtil.makeKeyFromPassPhrase(s2kDigestCalculator, encAlgorithm, s2k, passPhrase);
+    }
+
+    public S2K getS2K()
+    {
+        return s2k;
+    }
+
+    /**
+     * Key encryption method invoked for V4 keys and greater.
+     *
+     * @param keyData raw key data
+     * @param keyOff offset into rawe key data
+     * @param keyLen length of key data to use.
+     * @return an encryption of the passed in keyData.
+     * @throws PGPException on error in the underlying encryption process.
+     */
+    public byte[] encryptKeyData(byte[] keyData, int keyOff, int keyLen)
+        throws PGPException
+    {
+        if (s2k == null)
+        {
+            byte[]        iv = new byte[8];
+
+            random.nextBytes(iv);
+
+            s2k = new S2K(s2kDigestCalculator.getAlgorithm(), iv, s2kCount);
+        }
+
+        return encryptKeyData(getKey(), keyData, keyOff, keyLen);
+    }
+
+    public abstract byte[] encryptKeyData(byte[] key, byte[] keyData, int keyOff, int keyLen)
+        throws PGPException;
+
+    /**
+     * Encrypt the passed in keyData using the key and the iv provided.
+     * <p>
+     * This method is only used for processing version 3 keys.
+     * </p>
+     */
+    public byte[] encryptKeyData(byte[] key, byte[] iv, byte[] keyData, int keyOff, int keyLen)
+        throws PGPException
+    {
+        throw new PGPException("encryption of version 3 keys not supported.");
+    }
+
+    public abstract byte[] getCipherIV();
+}