1 files changed, 140 insertions, 0 deletions
diff --git a/sshlib/src/main/java/com/trilead/ssh2/signature/Ed25519Verify.java b/sshlib/src/main/java/com/trilead/ssh2/signature/Ed25519Verify.java
new file mode 100644
index 0000000..e6dd036
--- /dev/null
+++ b/sshlib/src/main/java/com/trilead/ssh2/signature/Ed25519Verify.java
@@ -0,0 +1,140 @@
+/*
+ * ConnectBot: simple, powerful, open-source SSH client for Android
+ * Copyright 2015 Kenny Root
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.trilead.ssh2.signature;
+
+import com.trilead.ssh2.crypto.key.Ed25519PrivateKey;
+import com.trilead.ssh2.crypto.key.Ed25519PublicKey;
+import com.trilead.ssh2.log.Logger;
+import com.trilead.ssh2.packets.TypesReader;
+import com.trilead.ssh2.packets.TypesWriter;
+import net.i2p.crypto.eddsa.EdDSAEngine;
+import net.i2p.crypto.eddsa.EdDSAPrivateKey;
+import net.i2p.crypto.eddsa.spec.EdDSANamedCurveSpec;
+import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable;
+import net.i2p.crypto.eddsa.spec.EdDSAPrivateKeySpec;
+import net.vrallev.java.ecc.Ecc25519Helper;
+
+import java.io.IOException;
+import java.security.InvalidKeyException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.SignatureException;
+
+/**
+ * @author Kenny Root
+ */
+public class Ed25519Verify {
+	private static final Logger log = Logger.getLogger(Ed25519Verify.class);
+
+	/** Identifies this as an Ed25519 key in the protocol. */
+	public static final String ED25519_ID = "ssh-ed25519";
+
+	private static final int ED25519_PK_SIZE_BYTES = 32;
+	private static final int ED25519_SIG_SIZE_BYTES = 64;
+
+	public static byte[] encodeSSHEd25519PublicKey(Ed25519PublicKey key) {
+		TypesWriter tw = new TypesWriter();
+
+		tw.writeString(ED25519_ID);
+		tw.writeBytes(key.getEncoded());
+
+		return tw.getBytes();
+	}
+
+	public static Ed25519PublicKey decodeSSHEd25519PublicKey(byte[] key) throws IOException {
+		TypesReader tr = new TypesReader(key);
+
+		String key_format = tr.readString();
+		if (key_format.equals(ED25519_ID) == false) {
+			throw new IOException("This is not an Ed25519 key");
+		}
+
+		byte[] keyBytes = tr.readByteString();
+
+		if (tr.remain() != 0) {
+			throw new IOException("Padding in Ed25519 public key! " + tr.remain() + " bytes left.");
+		}
+
+		if (keyBytes.length != ED25519_PK_SIZE_BYTES) {
+			throw new IOException("Ed25519 was not of correct length: " + keyBytes.length + " vs " + ED25519_PK_SIZE_BYTES);
+		}
+
+		return Ed25519PublicKey.getInstance(keyBytes);
+	}
+
+	public static byte[] generateSignature(byte[] msg, Ed25519PrivateKey privateKey) throws IOException {
+		byte[] privateKeyBytes = privateKey.getEncoded();
+
+		EdDSANamedCurveSpec spec = EdDSANamedCurveTable.getByName(EdDSANamedCurveTable.CURVE_ED25519_SHA512);
+		EdDSAPrivateKeySpec privKeySpec = new EdDSAPrivateKeySpec(privateKeyBytes, spec);
+
+		try {
+			EdDSAEngine engine = new EdDSAEngine(MessageDigest.getInstance("SHA-512"));
+			engine.initSign(new EdDSAPrivateKey(privKeySpec));
+			engine.update(msg);
+			return engine.sign();
+		} catch (NoSuchAlgorithmException e) {
+			throw new IOException(e);
+		} catch (SignatureException e) {
+			throw new IOException(e);
+		} catch (InvalidKeyException e) {
+			throw new IOException(e);
+		}
+	}
+
+	public static boolean verifySignature(byte[] msg, byte[] sig, Ed25519PublicKey publicKey) throws IOException {
+		byte[] publicKeyBytes = publicKey.getEncoded();
+		if (publicKeyBytes.length != ED25519_PK_SIZE_BYTES) {
+			throw new IOException("Invalid Ed25519 key length " + publicKeyBytes.length);
+		}
+		Ecc25519Helper helper = new Ecc25519Helper();
+		return helper.isValidSignature(msg, sig, publicKeyBytes);
+	}
+
+	public static byte[] encodeSSHEd25519Signature(byte[] sig) {
+		TypesWriter tw = new TypesWriter();
+
+		tw.writeString(ED25519_ID);
+		tw.writeBytes(sig);
+
+		return tw.getBytes();
+	}
+
+	public static byte[] decodeSSHEd25519Signature(byte[] sig) throws IOException {
+		byte[] rsArray;
+
+		TypesReader tr = new TypesReader(sig);
+
+		String sig_format = tr.readString();
+		if (sig_format.equals(ED25519_ID) == false) {
+			throw new IOException("Peer sent wrong signature format");
+		}
+
+		rsArray = tr.readByteString();
+
+		if (tr.remain() != 0) {
+			throw new IOException("Padding in Ed25519 signature!");
+		}
+
+		if (rsArray.length > ED25519_SIG_SIZE_BYTES) {
+			throw new IOException("Ed25519 signature was " + rsArray.length + " bytes (" + ED25519_PK_SIZE_BYTES + " expected)");
+		}
+
+		return rsArray;
+	}
+}