From 87e214761fade16ee40b0f5aa7da78ada1f92110 Mon Sep 17 00:00:00 2001
From: Albert Vaca <albertvaka@gmail.com>
Date: Thu, 3 Mar 2016 12:22:22 -0800
Subject: [PATCH] Made sshd use spongycastle instead of bouncycastle

We have to add the DHG14 key exchange factory by hand because when calling
setUpDefaultServer with Bouncy Castle disabled, it assumes DHG14 is not
supported (but it is, because we are adding spongycastle).
---
 .../kdeconnect/Plugins/SftpPlugin/SftpImpl.java   | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/org/kde/kdeconnect/Plugins/SftpPlugin/SftpImpl.java b/src/org/kde/kdeconnect/Plugins/SftpPlugin/SftpImpl.java
index b891f6ef..aa91adc5 100644
--- a/src/org/kde/kdeconnect/Plugins/SftpPlugin/SftpImpl.java
+++ b/src/org/kde/kdeconnect/Plugins/SftpPlugin/SftpImpl.java
@@ -24,6 +24,7 @@ import android.content.Context;
 import android.util.Log;
 
 import org.apache.sshd.SshServer;
+import org.apache.sshd.common.KeyExchange;
 import org.apache.sshd.common.NamedFactory;
 import org.apache.sshd.common.Session;
 import org.apache.sshd.common.file.FileSystemFactory;
@@ -36,6 +37,8 @@ import org.apache.sshd.server.Command;
 import org.apache.sshd.server.PasswordAuthenticator;
 import org.apache.sshd.server.PublickeyAuthenticator;
 import org.apache.sshd.server.command.ScpCommandFactory;
+import org.apache.sshd.server.kex.DHG1;
+import org.apache.sshd.server.kex.DHG14;
 import org.apache.sshd.server.keyprovider.SimpleGeneratorHostKeyProvider;
 import org.apache.sshd.server.session.ServerSession;
 import org.apache.sshd.server.sftp.SftpSubsystem;
@@ -48,6 +51,7 @@ import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.net.SocketException;
 import java.security.PublicKey;
+import java.security.Security;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -102,10 +106,18 @@ class SimpleSftpServer {
 
     public final SimplePasswordAuthenticator passwordAuth = new SimplePasswordAuthenticator();
     public final SimplePublicKeyAuthenticator keyAuth = new SimplePublicKeyAuthenticator();
+
+    static {
+        Security.insertProviderAt( new org.spongycastle.jce.provider.BouncyCastleProvider(), 1);
+        SecurityUtils.setRegisterBouncyCastle(false);
+    }
     private final SshServer sshd = SshServer.setUpDefaultServer();
 
-
     public void init(Context ctx, Device device) {
+        sshd.setKeyExchangeFactories(Arrays.asList(
+                new DHG14.Factory(),
+                new DHG1.Factory()));
+
         passwordAuth.setUser(USER);
         sshd.setKeyPairProvider(new SimpleGeneratorHostKeyProvider(ctx.getFilesDir() + "/sftpd.ser"));
 
@@ -134,6 +146,7 @@ class SimpleSftpServer {
                     sshd.start();
                     started = true;
                 } catch(Exception e) {
+                    e.printStackTrace();
                     port++;
                     if (port >= ENDPORT) {
                         port = -1;