- java api for secretsharing

14 files changed, 761 insertions, 0 deletions

diff --git a/src/main/java/org/gnunet/secretsharing/Ciphertext.java b/src/main/java/org/gnunet/secretsharing/Ciphertext.java
new file mode 100644
index 0000000..bb2962e
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/Ciphertext.java
@@ -0,0 +1,35 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import org.gnunet.construct.FixedSizeIntegerArray;
+import org.gnunet.construct.Message;
+
+/**
+ * ElGamal ciphertext
+ */
+public class Ciphertext implements Message {
+    @FixedSizeIntegerArray(signed = true, bitSize = 8, length = Parameters.elgamalBits / 8)
+    public byte[] c_1;
+
+    @FixedSizeIntegerArray(signed = true, bitSize = 8, length = Parameters.elgamalBits / 8)
+    public byte[] c_2;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/Decryption.java b/src/main/java/org/gnunet/secretsharing/Decryption.java
new file mode 100644
index 0000000..76197fb
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/Decryption.java
@@ -0,0 +1,88 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import org.gnunet.secretsharing.callbacks.DecryptCallback;
+import org.gnunet.secretsharing.messages.ClientDecryptMessage;
+import org.gnunet.secretsharing.messages.DecryptDoneMessage;
+import org.gnunet.util.AbsoluteTime;
+import org.gnunet.util.Client;
+import org.gnunet.util.Configuration;
+import org.gnunet.util.RunaboutMessageReceiver;
+
+/**
+ * Cooperatively decrypt a ciphertext.
+ */
+public class Decryption {
+    private Client client;
+    private DecryptCallback decryptCallback;
+
+    private class DecryptionReceiver extends RunaboutMessageReceiver {
+        public void visit(DecryptDoneMessage m) {
+            if (m.success != 0) {
+                decryptCallback.onResult(m.plaintext);
+            } else {
+                decryptCallback.onResult(null);
+            }
+            client.disconnect();
+            client = null;
+        }
+        @Override
+        public void handleError() {
+            decryptCallback.onResult(null);
+        }
+    }
+
+    /**
+     * Cooperatively decrypt a ciphertext encrypted with a
+     * threshold key.
+     *
+     * @param configuration configuration to use for connecting to the
+     *                      secretsharing service
+     * @param share the local peer's share of the threshold key
+     * @param ciphertext ciphertext to decrypt
+     * @param start when should we start decrypting?
+     * @param deadline when should decryption be finished?
+     * @param decryptCallback called when the decryption finished, or
+     *                        an error occurred.
+     */
+    public Decryption(Configuration configuration, Share share, Ciphertext ciphertext,
+                      AbsoluteTime start, AbsoluteTime deadline, DecryptCallback decryptCallback) {
+        this.decryptCallback = decryptCallback;
+        client = new Client("secretsharing", configuration);
+        client.installReceiver(new DecryptionReceiver());
+
+        ClientDecryptMessage m = new ClientDecryptMessage();
+        m.ciphertext = ciphertext;
+        m.deadline = deadline.asMessage();
+        m.start = start.asMessage();
+        m.share = share;
+
+        client.send(m);
+    }
+
+    public void disconnect() {
+        if (null != client) {
+            client.disconnect();
+            client = null;
+        }
+    }
+}
diff --git a/src/main/java/org/gnunet/secretsharing/FieldElement.java b/src/main/java/org/gnunet/secretsharing/FieldElement.java
new file mode 100644
index 0000000..e1fcac6
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/FieldElement.java
@@ -0,0 +1,29 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import org.gnunet.construct.FixedSizeIntegerArray;
+import org.gnunet.construct.Message;
+
+public class FieldElement implements Message {
+    @FixedSizeIntegerArray(signed = true, bitSize = 8, length = Parameters.elgamalBits / 8)
+    public byte[] bits;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/KeyGeneration.java b/src/main/java/org/gnunet/secretsharing/KeyGeneration.java
new file mode 100644
index 0000000..8b9a759
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/KeyGeneration.java
@@ -0,0 +1,88 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import org.gnunet.secretsharing.callbacks.SecretReadyCallback;
+import org.gnunet.secretsharing.messages.GenerateMessage;
+import org.gnunet.secretsharing.messages.SecretReadyMessage;
+import org.gnunet.util.*;
+
+/**
+ * Key generation session.
+ */
+public class KeyGeneration {
+    private Client client;
+    private SecretReadyCallback secretReadyCallback;
+
+    private class KeyGenerationReceiver extends RunaboutMessageReceiver {
+        public void visit(SecretReadyMessage m) {
+            secretReadyCallback.onSecretReady(m.share);
+            client.disconnect();
+            client = null;
+        }
+        @Override
+        public void handleError() {
+            secretReadyCallback.onSecretReady(null);
+        }
+    }
+
+    /**
+     * Generate a threshold key pair.
+     *
+     * @param configuration configuratio to use
+     * @param peers peers in the session, the local peer is optional
+     * @param sessionId session id
+     * @param start when should we start to generate the key with other peers?
+     * @param deadline when should the key generation be finished?
+     * @param threshold minimum number of peers required to decrypt a ciphertext
+     * @param secretReadyCallback called when the key has been generated or
+     *                            an error occured
+     */
+    public KeyGeneration(Configuration configuration, PeerIdentity[] peers,
+                         HashCode sessionId, AbsoluteTime start, AbsoluteTime deadline,
+                         int threshold, SecretReadyCallback secretReadyCallback) {
+        this.client = new Client("secretsharing", configuration);
+        this.secretReadyCallback = secretReadyCallback;
+
+        client.installReceiver(new KeyGenerationReceiver());
+
+        GenerateMessage m = new GenerateMessage();
+        m.start = start.asMessage();
+        m.deadline = deadline.asMessage();
+        m.threshold = threshold;
+        m.numPeers = peers.length;
+        m.peers = peers;
+        m.sessionId = sessionId;
+
+        client.send(m);
+    }
+
+    /**
+     * Disconnect from the secretsharing service and cancel the operation.
+     * The SecretReadyCallback will not be called after calling disconnect.
+     */
+    public void disconnect() {
+        if (null != client) {
+            client.disconnect();
+            client = null;
+        }
+    }
+}
diff --git a/src/main/java/org/gnunet/secretsharing/Parameters.java b/src/main/java/org/gnunet/secretsharing/Parameters.java
new file mode 100644
index 0000000..cd0e5de
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/Parameters.java
@@ -0,0 +1,69 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import java.math.BigInteger;
+
+/**
+ * Constants used by the crypto of the secretsharing API.
+ */
+public interface Parameters {
+    /**
+     * Size of the key.
+     */
+    public static final int elgamalBits = 1024;
+
+    /**
+     * Order of the group.
+     */
+    public static final BigInteger elgamalQ = new BigInteger(
+            "0451a3e9eb4f4596ebe8d895046fde65f5fa65" +
+            "37a134d040a70ac51a1894b26ca359f79144118b" +
+            "95e7987e047bb93ba65a027cde001537b3584d3c" +
+            "ec086b3e27c659df6e303071e477c3a58db26fb8" +
+            "b63e958016d4407134a1c6ad3bb735af929e46fa" +
+            "b50b58e3e72c6f783e01eda411c556fe2951aa51" +
+            "3f6942d860b3ae569f9", 16);
+
+    /**
+     * Modulus of the group.
+     */
+    public static final BigInteger elgamalP = new BigInteger(
+            "08a347d3d69e8b2dd7d1b12a08dfbccbebf4ca" +
+                    "6f4269a0814e158a34312964d946b3ef22882317" +
+                    "2bcf30fc08f772774cb404f9bc002a6f66b09a79" +
+                    "d810d67c4f8cb3bedc6060e3c8ef874b1b64df71" +
+                    "6c7d2b002da880e269438d5a776e6b5f253c8df5" +
+                    "6a16b1c7ce58def07c03db48238aadfc52a354a2" +
+                    "7ed285b0c1675cad3f3", 16);
+
+    /**
+     * Generator of the group.
+     */
+    public static final BigInteger elgamalG = new BigInteger(
+            "05c00c36d2e822950087ef09d8252994adc4e4" +
+            "8fe3ec70269f035b46063aff0c99b633fd64df43" +
+            "02442e1914c829a41505a275438871f365e91c12" +
+            "3d5303ef9e90f4b8cb89bf86cc9b513e74a72634" +
+            "9cfd9f953674fab5d511e1c078fc72d72b34086f" +
+            "c82b4b951989eb85325cb203ff98df76bc366bba" +
+            "1d7024c3650f60d0da", 16);
+}
diff --git a/src/main/java/org/gnunet/secretsharing/Plaintext.java b/src/main/java/org/gnunet/secretsharing/Plaintext.java
new file mode 100644
index 0000000..c4fdd3e
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/Plaintext.java
@@ -0,0 +1,90 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import com.google.common.base.Preconditions;
+import org.gnunet.construct.FixedSizeIntegerArray;
+import org.gnunet.construct.Message;
+
+import java.math.BigInteger;
+import java.security.SecureRandom;
+
+public class Plaintext implements Message {
+    @FixedSizeIntegerArray(signed = true, bitSize = 8, length = Parameters.elgamalBits / 8)
+    public byte[] bits;
+
+    public static Plaintext generate(BigInteger exp) {
+        BigInteger val;
+        val = Parameters.elgamalG.modPow(exp, Parameters.elgamalP);
+        Plaintext plaintext = new Plaintext();
+        plaintext.bits = serializeBigIntUnsigned(val, Parameters.elgamalBits);
+        return plaintext;
+    }
+
+    /**
+     * Serialize a BigInteger, but do not add an extra bit for a
+     * sign.
+     *
+     * @param bigInteger
+     * @param bits
+     * @return
+     */
+    private static byte[] serializeBigIntUnsigned(BigInteger bigInteger, int bits) {
+        byte[] bytes = bigInteger.toByteArray();
+        int start;
+        Preconditions.checkArgument(bigInteger.bitCount() <= bits);
+        // skip byte that was only added to fit the sign
+        if (bytes[0] == 0) {
+            start = 1;
+        } else {
+            start = 0;
+        }
+        byte[] fixedBytes = new byte[(bits + 7) / 8];
+        System.arraycopy(bytes, start, fixedBytes,
+                fixedBytes.length - bytes.length + start, bytes.length - start);
+        return fixedBytes;
+    }
+
+    public Ciphertext encrypt(ThresholdPublicKey publicKey) {
+        SecureRandom secureRandom = new SecureRandom();
+        BigInteger c_1;
+        BigInteger c_2;
+        BigInteger y;
+        BigInteger m;
+        BigInteger h;
+
+        m = new BigInteger(1, this.bits);
+        h = new BigInteger(1, publicKey.bits);
+
+        do {
+            y = new BigInteger(Parameters.elgamalBits - 1, secureRandom);
+        } while (y.compareTo(BigInteger.ONE) == 0 || y.compareTo(Parameters.elgamalQ) >= 0);
+
+        c_1 = Parameters.elgamalG.modPow(y, Parameters.elgamalP);
+        c_2 = m.multiply(h.modPow(y, Parameters.elgamalP)).mod(Parameters.elgamalP);
+
+        Ciphertext ciphertext = new Ciphertext();
+        ciphertext.c_1 = serializeBigIntUnsigned(c_1, Parameters.elgamalBits);
+        ciphertext.c_2 = serializeBigIntUnsigned(c_2, Parameters.elgamalBits);
+
+        return ciphertext;
+    }
+}
diff --git a/src/main/java/org/gnunet/secretsharing/Share.java b/src/main/java/org/gnunet/secretsharing/Share.java
new file mode 100644
index 0000000..5389031
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/Share.java
@@ -0,0 +1,63 @@
+package org.gnunet.secretsharing;
+
+import org.gnunet.construct.*;
+import org.gnunet.util.PeerIdentity;
+
+/**
+ * Share of the threshold secret key.  Contains both the
+ * public key as well as one peer's private share.
+ */
+public class Share implements Message {
+    /**
+     * Threshold for the key this share belongs to.
+     */
+    @UInt16
+    public int threshold;
+
+    /**
+     * Peers that have the share.
+     */
+    @UInt16
+    public int numPeers;
+
+    /**
+     * Index of our peer in the list.
+     */
+    @UInt16
+    public int myPeer;
+
+    /**
+     * Padding, always zero.
+     */
+    @UInt16
+    public int padding;
+
+    /**
+     * Public key. Must correspond to the product of
+     * the homomorphic share commitments.
+     */
+    @NestedMessage
+    public ThresholdPublicKey publicKey;
+
+    /**
+     * Share of 'my_peer'
+     */
+    @NestedMessage
+    public FieldElement myShare;
+
+    /**
+     * Peers that have a share of the secret.
+     */
+    @VariableSizeArray(lengthField = "numPeers")
+    public PeerIdentity[] peerIdentities;
+
+    /**
+     * Sigma for each peer.  The sigma is pow(g,s)
+     * where g is the generator and s is the peer's share.
+     */
+    @VariableSizeArray(lengthField = "numPeers")
+    public FieldElement[] sigmas;
+
+    @VariableSizeIntegerArray(lengthField = "numPeers", bitSize = 16, signed = false)
+    public int[] originalIndices;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/ThresholdPublicKey.java b/src/main/java/org/gnunet/secretsharing/ThresholdPublicKey.java
new file mode 100644
index 0000000..b7075be
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/ThresholdPublicKey.java
@@ -0,0 +1,32 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing;
+
+import org.gnunet.construct.FixedSizeIntegerArray;
+import org.gnunet.construct.Message;
+
+/**
+ * Threshold public key.
+ */
+public class ThresholdPublicKey implements Message {
+    @FixedSizeIntegerArray(signed = true, bitSize = 8, length = Parameters.elgamalBits / 8)
+    public byte[] bits;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/callbacks/DecryptCallback.java b/src/main/java/org/gnunet/secretsharing/callbacks/DecryptCallback.java
new file mode 100644
index 0000000..1947811
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/callbacks/DecryptCallback.java
@@ -0,0 +1,35 @@
+/*
+ This file is part of GNUnet.
+  (C) 2014 Christian Grothoff (and other contributing authors)
+
+  GNUnet is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 3, or (at your
+  option) any later version.
+
+  GNUnet is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with GNUnet; see the file COPYING.  If not, write to the
+  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+  Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing.callbacks;
+
+import org.gnunet.secretsharing.Plaintext;
+
+/**
+ * Callback for when the secretsharing service has decrypted a ciphertext.
+ */
+public interface DecryptCallback {
+    /**
+     * Called when the secretsharing service has decrypted a ciphertext.
+     *
+     * @param plaintext the plaintext, or null on error
+     */
+    void onResult(Plaintext plaintext);
+}
diff --git a/src/main/java/org/gnunet/secretsharing/callbacks/SecretReadyCallback.java b/src/main/java/org/gnunet/secretsharing/callbacks/SecretReadyCallback.java
new file mode 100644
index 0000000..a2ca57c
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/callbacks/SecretReadyCallback.java
@@ -0,0 +1,35 @@
+/*
+ This file is part of GNUnet.
+  (C) 2014 Christian Grothoff (and other contributing authors)
+
+  GNUnet is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 3, or (at your
+  option) any later version.
+
+  GNUnet is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with GNUnet; see the file COPYING.  If not, write to the
+  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+  Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing.callbacks;
+
+import org.gnunet.secretsharing.Share;
+
+/**
+ * Callback for when shared secret key has been established.
+ */
+public interface SecretReadyCallback {
+    /**
+     * Called when the shared secret key has been established.
+     * @param share the share for the local peer, including the public key,
+     *              or null on error
+     */
+    public void onSecretReady(Share share);
+}
diff --git a/src/main/java/org/gnunet/secretsharing/messages/ClientDecryptMessage.java b/src/main/java/org/gnunet/secretsharing/messages/ClientDecryptMessage.java
new file mode 100644
index 0000000..1dc0981
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/messages/ClientDecryptMessage.java
@@ -0,0 +1,59 @@
+/*
+ This file is part of GNUnet.
+  (C) 2014 Christian Grothoff (and other contributing authors)
+
+  GNUnet is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 3, or (at your
+  option) any later version.
+
+  GNUnet is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with GNUnet; see the file COPYING.  If not, write to the
+  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+  Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing.messages;
+
+import org.gnunet.construct.NestedMessage;
+import org.gnunet.construct.UnionCase;
+import org.gnunet.secretsharing.Ciphertext;
+import org.gnunet.secretsharing.Share;
+import org.gnunet.util.AbsoluteTimeMessage;
+import org.gnunet.util.GnunetMessage;
+
+/**
+ * Sent by the client to the service to request the cooperative decryption of a
+ * ciphertext.
+ */
+@UnionCase(781)
+public class ClientDecryptMessage implements GnunetMessage.Body {
+    /**
+     * When should communication with other peers start?
+     */
+    @NestedMessage
+    public AbsoluteTimeMessage start;
+
+    /**
+     * When should the operation have finished?
+     */
+    @NestedMessage
+    public AbsoluteTimeMessage deadline;
+
+    /**
+     * Ciphertext to cooperatively decrypt.
+     */
+    @NestedMessage
+    public Ciphertext ciphertext;
+
+    /**
+     * Our share of the secret key.
+     */
+    @NestedMessage
+    public Share share;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/messages/DecryptDoneMessage.java b/src/main/java/org/gnunet/secretsharing/messages/DecryptDoneMessage.java
new file mode 100644
index 0000000..71f24da
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/messages/DecryptDoneMessage.java
@@ -0,0 +1,48 @@
+/*
+
+  This file is part of GNUnet.
+   (C) 2014 Christian Grothoff (and other contributing authors)
+
+   GNUnet is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GNUnet is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GNUnet; see the file COPYING.  If not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+
+ */
+
+package org.gnunet.secretsharing.messages;
+
+import org.gnunet.construct.NestedMessage;
+import org.gnunet.construct.UInt32;
+import org.gnunet.construct.UnionCase;
+import org.gnunet.secretsharing.Plaintext;
+import org.gnunet.util.GnunetMessage;
+
+/**
+ * Created by dold on 2/2/14.
+ */
+@UnionCase(782)
+public class DecryptDoneMessage implements GnunetMessage.Body{
+
+    /**
+     * Was the decryption successful?
+     */
+    @UInt32
+    public int success;
+
+    /**
+     * Plaintext, only valid if 'success' is non-zero.
+     */
+    @NestedMessage
+    public Plaintext plaintext;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/messages/GenerateMessage.java b/src/main/java/org/gnunet/secretsharing/messages/GenerateMessage.java
new file mode 100644
index 0000000..b1ce6b2
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/messages/GenerateMessage.java
@@ -0,0 +1,51 @@
+/*
+
+   This file is part of GNUnet.
+   (C) 2014 Christian Grothoff (and other contributing authors)
+
+   GNUnet is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GNUnet is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GNUnet; see the file COPYING.  If not, write to the
+   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+
+ */
+
+package org.gnunet.secretsharing.messages;
+
+import org.gnunet.construct.NestedMessage;
+import org.gnunet.construct.UInt16;
+import org.gnunet.construct.UnionCase;
+import org.gnunet.construct.VariableSizeArray;
+import org.gnunet.util.*;
+
+
+@UnionCase(780)
+public class GenerateMessage implements GnunetMessage.Body {
+    @NestedMessage
+    public HashCode sessionId;
+
+    @NestedMessage
+    public AbsoluteTimeMessage start;
+
+    @NestedMessage
+    public AbsoluteTimeMessage deadline;
+
+    @UInt16
+    public int threshold;
+
+    @UInt16
+    public int numPeers;
+
+    @VariableSizeArray(lengthField = "numPeers")
+    public PeerIdentity[] peers;
+}
diff --git a/src/main/java/org/gnunet/secretsharing/messages/SecretReadyMessage.java b/src/main/java/org/gnunet/secretsharing/messages/SecretReadyMessage.java
new file mode 100644
index 0000000..479fe2c
--- /dev/null
+++ b/src/main/java/org/gnunet/secretsharing/messages/SecretReadyMessage.java
@@ -0,0 +1,39 @@
+/*
+ This file is part of GNUnet.
+ (C) 2014 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+ */
+
+package org.gnunet.secretsharing.messages;
+
+import org.gnunet.construct.NestedMessage;
+import org.gnunet.construct.UnionCase;
+import org.gnunet.secretsharing.Share;
+import org.gnunet.util.GnunetMessage;
+
+/**
+ * Sent by the service to the client when the key generation
+ * has been successful.
+ */
+@UnionCase(783)
+public class SecretReadyMessage implements GnunetMessage.Body {
+    /**
+     * Share for the local peer.
+     */
+    @NestedMessage
+    public Share share;
+}