diff --git a/Readme.md b/Readme.md
index abc6269a..39035536 100644
--- a/Readme.md
+++ b/Readme.md
@@ -64,6 +64,7 @@ As I explained in a [blog post](http://www.matez.de/index.php/2020/06/22/the-fut
   * This library is a Multi-Release-jar, which means that you can only use certain features when a more recent Java version is used.
     * In order to use ssh-ed25519 & ssh-ed448, you must use at least Java 15.
     * In order to use curve25519-sha256, curve448-sha512 & chacha20-poly1305@<!-- -->openssh.com, you must use at least Java 11.
+  * As of the [0.1.66](https://github.com/mwiede/jsch/releases/tag/jsch-0.1.66) release, these algorithms can now be used with older Java releases if [Bouncy Castle](https://www.bouncycastle.org/) (bcprov-jdk15on) is added to the classpath.
 
 ## Changes since fork:
 * [0.1.66](https://github.com/mwiede/jsch/releases/tag/jsch-0.1.66)
@@ -99,6 +100,13 @@ As I explained in a [blog post](http://www.matez.de/index.php/2020/06/22/the-fut
     * See `examples/JSchWithAgentProxy.java` for simple example
     * ssh-agent support requires either [Java 16's JEP 380](https://openjdk.java.net/jeps/380) or the addition of [junixsocket](https://github.com/kohlschutter/junixsocket) to classpath
     * Pageant support is untested & requires the addition of [JNA](https://github.com/java-native-access/jna) to classpath
+  * Added support for the following algorithms with older Java releases by using [Bouncy Castle](https://www.bouncycastle.org/):
+    * ssh-ed25519
+    * ssh-ed448
+    * curve25519-sha256
+    * curve25519-sha256@<!-- -->libssh.org
+    * curve448-sha512
+    * chacha20-poly1305@<!-- -->openssh.com
 * [0.1.65](https://github.com/mwiede/jsch/releases/tag/jsch-0.1.65)
   * Added system properties to allow manipulation of various crypto algorithms used by default
   * Integrated JZlib, allowing use of zlib@<!-- -->openssh.com & zlib compressions without the need to provide the JZlib jar-file
diff --git a/pom.xml b/pom.xml
index 19812b80..4f197228 100644
--- a/pom.xml
+++ b/pom.xml
@@ -50,6 +50,12 @@
         <jna.version>5.9.0</jna.version>
     </properties>
     <dependencies>
+        <dependency>
+            <groupId>org.bouncycastle</groupId>
+            <artifactId>bcprov-jdk15on</artifactId>
+            <version>1.69</version>
+            <optional>true</optional>
+        </dependency>
         <dependency>
             <groupId>com.kohlschutter.junixsocket</groupId>
             <artifactId>junixsocket-common</artifactId>
diff --git a/src/main/java/com/jcraft/jsch/DHXEC.java b/src/main/java/com/jcraft/jsch/DHXEC.java
index 4bbeeeac..b1100207 100644
--- a/src/main/java/com/jcraft/jsch/DHXEC.java
+++ b/src/main/java/com/jcraft/jsch/DHXEC.java
@@ -89,7 +89,7 @@ public void init(Session session,
       Q_C = xdh.getQ();
       buf.putString(Q_C);
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
       throw new JSchException(e.toString(), e);
     }
 
diff --git a/src/main/java/com/jcraft/jsch/JSch.java b/src/main/java/com/jcraft/jsch/JSch.java
index 6a83e70d..e6f6569e 100644
--- a/src/main/java/com/jcraft/jsch/JSch.java
+++ b/src/main/java/com/jcraft/jsch/JSch.java
@@ -106,13 +106,9 @@ public class JSch{
 
     config.put("ecdh-sha2-nistp", "com.jcraft.jsch.jce.ECDHN");
 
-    config.put("ssh-ed25519", "com.jcraft.jsch.jce.SignatureEd25519");
-    config.put("ssh-ed448",   "com.jcraft.jsch.jce.SignatureEd448");
-
     config.put("curve25519-sha256",            "com.jcraft.jsch.DH25519");
     config.put("curve25519-sha256@libssh.org", "com.jcraft.jsch.DH25519");
     config.put("curve448-sha512",              "com.jcraft.jsch.DH448");
-    config.put("xdh", "com.jcraft.jsch.jce.XDH");
 
     config.put("dh",            "com.jcraft.jsch.jce.DH");
     config.put("3des-cbc",      "com.jcraft.jsch.jce.TripleDESCBC");
@@ -156,12 +152,10 @@ public class JSch{
     config.put("keypairgen.dsa",   "com.jcraft.jsch.jce.KeyPairGenDSA");
     config.put("keypairgen.rsa",   "com.jcraft.jsch.jce.KeyPairGenRSA");
     config.put("keypairgen.ecdsa", "com.jcraft.jsch.jce.KeyPairGenECDSA");
-    config.put("keypairgen.eddsa", "com.jcraft.jsch.jce.KeyPairGenEdDSA");
     config.put("random",        "com.jcraft.jsch.jce.Random");
 
     config.put("none",           "com.jcraft.jsch.CipherNone");
 
-    config.put("chacha20-poly1305@openssh.com",    "com.jcraft.jsch.jce.ChaCha20Poly1305");
     config.put("aes128-gcm@openssh.com",    "com.jcraft.jsch.jce.AES128GCM");
     config.put("aes256-gcm@openssh.com",    "com.jcraft.jsch.jce.AES256GCM");
 
@@ -189,6 +183,26 @@ public class JSch{
 
     config.put("pbkdf", "com.jcraft.jsch.jce.PBKDF");
 
+    if(JavaVersion.getVersion()>=11){
+      config.put("chacha20-poly1305@openssh.com", "com.jcraft.jsch.jce.ChaCha20Poly1305");
+      config.put("xdh", "com.jcraft.jsch.jce.XDH");
+    }
+    else{
+      config.put("chacha20-poly1305@openssh.com", "com.jcraft.jsch.bc.ChaCha20Poly1305");
+      config.put("xdh", "com.jcraft.jsch.bc.XDH");
+    }
+
+    if(JavaVersion.getVersion()>=15){
+      config.put("keypairgen.eddsa", "com.jcraft.jsch.jce.KeyPairGenEdDSA");
+      config.put("ssh-ed25519", "com.jcraft.jsch.jce.SignatureEd25519");
+      config.put("ssh-ed448", "com.jcraft.jsch.jce.SignatureEd448");
+    }
+    else{
+      config.put("keypairgen.eddsa", "com.jcraft.jsch.bc.KeyPairGenEdDSA");
+      config.put("ssh-ed25519", "com.jcraft.jsch.bc.SignatureEd25519");
+      config.put("ssh-ed448", "com.jcraft.jsch.bc.SignatureEd448");
+    }
+
     config.put("StrictHostKeyChecking",  "ask");
     config.put("HashKnownHosts",  "no");
 
diff --git a/src/main/java/com/jcraft/jsch/JavaVersion.java b/src/main/java/com/jcraft/jsch/JavaVersion.java
new file mode 100644
index 00000000..b6184b14
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/JavaVersion.java
@@ -0,0 +1,8 @@
+package com.jcraft.jsch;
+
+final class JavaVersion {
+
+  static int getVersion() {
+    return 8;
+  }
+}
diff --git a/src/main/java/com/jcraft/jsch/KeyExchange.java b/src/main/java/com/jcraft/jsch/KeyExchange.java
index cd2e86f9..cb611909 100644
--- a/src/main/java/com/jcraft/jsch/KeyExchange.java
+++ b/src/main/java/com/jcraft/jsch/KeyExchange.java
@@ -143,18 +143,25 @@ else if(guess[i]==null){
       }
     }
 
-    Class<?> _s2cclazz=Class.forName(session.getConfig(guess[PROPOSAL_ENC_ALGS_STOC]));
-    Cipher _s2ccipher=(Cipher)(_s2cclazz.getDeclaredConstructor().newInstance());
-    boolean _s2cAEAD=_s2ccipher.isAEAD();
-    if(_s2cAEAD){
-      guess[PROPOSAL_MAC_ALGS_STOC]=null;
-    }
+    boolean _s2cAEAD=false;
+    boolean _c2sAEAD=false;
+    try{
+      Class<?> _s2cclazz=Class.forName(session.getConfig(guess[PROPOSAL_ENC_ALGS_STOC]));
+      Cipher _s2ccipher=(Cipher)(_s2cclazz.getDeclaredConstructor().newInstance());
+      _s2cAEAD=_s2ccipher.isAEAD();
+      if(_s2cAEAD){
+        guess[PROPOSAL_MAC_ALGS_STOC]=null;
+      }
 
-    Class<?> _c2sclazz=Class.forName(session.getConfig(guess[PROPOSAL_ENC_ALGS_CTOS]));
-    Cipher _c2scipher=(Cipher)(_c2sclazz.getDeclaredConstructor().newInstance());
-    boolean _c2sAEAD=_c2scipher.isAEAD();
-    if(_c2sAEAD){
-      guess[PROPOSAL_MAC_ALGS_CTOS]=null;
+      Class<?> _c2sclazz=Class.forName(session.getConfig(guess[PROPOSAL_ENC_ALGS_CTOS]));
+      Cipher _c2scipher=(Cipher)(_c2sclazz.getDeclaredConstructor().newInstance());
+      _c2sAEAD=_c2scipher.isAEAD();
+      if(_c2sAEAD){
+        guess[PROPOSAL_MAC_ALGS_CTOS]=null;
+      }
+    }
+    catch(Exception | NoClassDefFoundError e){
+      throw new JSchException(e.toString(), e);
     }
 
     if(JSch.getLogger().isEnabled(Logger.INFO)){
@@ -361,7 +368,7 @@ else if(alg.equals("ssh-ed25519") ||
         sig=(SignatureEdDSA)(c.getDeclaredConstructor().newInstance());
         sig.init();
       }
-      catch(Exception e){
+      catch(Exception | NoClassDefFoundError e){
         System.err.println(e);
       }
 
diff --git a/src/main/java/com/jcraft/jsch/KeyPairEdDSA.java b/src/main/java/com/jcraft/jsch/KeyPairEdDSA.java
index 585a5be5..92d6a43f 100644
--- a/src/main/java/com/jcraft/jsch/KeyPairEdDSA.java
+++ b/src/main/java/com/jcraft/jsch/KeyPairEdDSA.java
@@ -57,7 +57,7 @@ void generate(int key_size) throws JSchException{
 
       keypairgen=null;
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
       //System.err.println("KeyPairEdDSA: "+e);
       throw new JSchException(e.toString(), e);
     }
@@ -134,7 +134,7 @@ public byte[] getSignature(byte[] data, String alg){
       tmp[1] = sig;
       return Buffer.fromBytes(tmp).buffer;
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
     }
     return null;
   }
@@ -160,7 +160,7 @@ public Signature getVerifier(String alg){
       eddsa.setPubKey(pub_array);
       return eddsa;
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
     }
     return null;
   }
diff --git a/src/main/java/com/jcraft/jsch/Session.java b/src/main/java/com/jcraft/jsch/Session.java
index 69e1bf34..80d807a7 100644
--- a/src/main/java/com/jcraft/jsch/Session.java
+++ b/src/main/java/com/jcraft/jsch/Session.java
@@ -610,7 +610,7 @@ private KeyExchange receive_kexinit(Buffer buf) throws Exception {
       Class<?> c=Class.forName(getConfig(guess[KeyExchange.PROPOSAL_KEX_ALGS]));
       kex=(KeyExchange)(c.getDeclaredConstructor().newInstance());
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
       throw new JSchException(e.toString(), e);
     }
 
@@ -1528,7 +1528,7 @@ private void updateKeys(KeyExchange kex) throws Exception{
       method=guess[KeyExchange.PROPOSAL_COMP_ALGS_STOC];
       initInflater(method);
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
       if(e instanceof JSchException)
         throw e;
       throw new JSchException(e.toString(), e);
@@ -2574,9 +2574,6 @@ private void initDeflater(String method) throws JSchException{
           catch(Exception ee){ }
           deflater.init(Compression.DEFLATER, level);
         }
-        catch(NoClassDefFoundError ee){
-          throw new JSchException(ee.toString(), ee);
-        }
         catch(Exception ee){
           throw new JSchException(ee.toString(), ee);
           //System.err.println(foo+" isn't accessible.");
@@ -2855,7 +2852,7 @@ static boolean checkCipher(String cipher){
               new byte[_c.getIVSize()]);
       return true;
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
       return false;
     }
   }
@@ -2904,7 +2901,7 @@ static boolean checkMac(String mac){
       _c.init(new byte[_c.getBlockSize()]);
       return true;
     }
-    catch(Exception e){
+    catch(Exception | NoClassDefFoundError e){
       return false;
     }
   }
@@ -2947,7 +2944,7 @@ static boolean checkKex(Session s, String kex){
       _c.init(s ,null, null, null, null);
       return true;
     }
-    catch(Exception e){ return false; }
+    catch(Exception | NoClassDefFoundError e){ return false; }
   }
 
   private String[] checkSignatures(String sigs){
@@ -2967,7 +2964,7 @@ private String[] checkSignatures(String sigs){
         final Signature sig=(Signature)(c.getDeclaredConstructor().newInstance());
         sig.init();
       }
-      catch(Exception e){
+      catch(Exception | NoClassDefFoundError e){
         result.addElement(_sigs[i]);
       }
    }
diff --git a/src/main/java/com/jcraft/jsch/bc/ChaCha20Poly1305.java b/src/main/java/com/jcraft/jsch/bc/ChaCha20Poly1305.java
new file mode 100644
index 00000000..8ab84dc9
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/bc/ChaCha20Poly1305.java
@@ -0,0 +1,138 @@
+/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
+/*
+Copyright (c) 2008-2018 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright 
+     notice, this list of conditions and the following disclaimer in 
+     the documentation and/or other materials provided with the distribution.
+
+  3. The names of the authors may not be used to endorse or promote products
+     derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.jcraft.jsch.bc;
+
+import com.jcraft.jsch.Cipher;
+import com.jcraft.jsch.openjax.Poly1305;
+import java.nio.ByteBuffer;
+import javax.crypto.AEADBadTagException;
+import org.bouncycastle.crypto.engines.ChaChaEngine;
+import org.bouncycastle.crypto.params.*;
+
+public class ChaCha20Poly1305 implements Cipher{
+  //Actually the block size, not IV size
+  private static final int ivsize=8;
+  //Actually the key size, not block size
+  private static final int bsize=64;
+  private static final int tagsize=16;
+  private ChaChaEngine header_cipher;
+  private ChaChaEngine main_cipher;
+  private KeyParameter K_1_spec;
+  private KeyParameter K_2_spec;
+  private int mode;
+  private Poly1305 poly1305;
+  @Override
+  public int getIVSize(){return ivsize;}
+  @Override
+  public int getBlockSize(){return bsize;}
+  @Override
+  public int getTagSize(){return tagsize;}
+  @Override
+  public void init(int mode, byte[] key, byte[] iv) throws Exception{
+    byte[] tmp;
+    if(key.length>bsize){
+      tmp=new byte[bsize];
+      System.arraycopy(key, 0, tmp, 0, tmp.length);
+      key=tmp;
+    }
+    byte[] K_1=new byte[bsize/2];
+    byte[] K_2=new byte[bsize/2];
+    System.arraycopy(key, bsize/2, K_1, 0, bsize/2);
+    System.arraycopy(key, 0, K_2, 0, bsize/2);
+    this.mode=mode;
+    try{
+      K_1_spec=new KeyParameter(K_1);
+      K_2_spec=new KeyParameter(K_2);
+      header_cipher=new ChaChaEngine();
+      main_cipher=new ChaChaEngine();
+    }
+    catch(Exception e){
+      header_cipher=null;
+      main_cipher=null;
+      K_1_spec=null;
+      K_2_spec=null;
+      throw e;
+    }
+  }
+  @Override
+  public void update(int foo) throws Exception{
+    ByteBuffer nonce=ByteBuffer.allocate(8);
+    nonce.putLong(0, foo);
+    header_cipher.init(this.mode==ENCRYPT_MODE, new ParametersWithIV(K_1_spec, nonce.array()));
+    main_cipher.init(this.mode==ENCRYPT_MODE, new ParametersWithIV(K_2_spec, nonce.array()));
+    // Trying to reinit the cipher again with same nonce results in InvalidKeyException
+    // So just read entire first 64-byte block, which should increment global counter from 0->1
+    byte[] poly_key = new byte[32];
+    byte[] discard = new byte[32];
+    main_cipher.processBytes(poly_key, 0, 32, poly_key, 0);
+    main_cipher.processBytes(discard, 0, 32, discard, 0);
+    poly1305 = new Poly1305(poly_key);
+  }
+  @Override
+  public void update(byte[] foo, int s1, int len, byte[] bar, int s2) throws Exception{
+    header_cipher.processBytes(foo, s1, len, bar, s2);
+  }
+  @Override
+  public void updateAAD(byte[] foo, int s1, int len) throws Exception{
+  }
+  @Override
+  public void doFinal(byte[] foo, int s1, int len, byte[] bar, int s2) throws Exception{
+    if(this.mode==DECRYPT_MODE){
+      byte[] actual_tag = new byte[tagsize];
+      System.arraycopy(foo, len, actual_tag, 0, tagsize);
+      byte[] expected_tag = new byte[tagsize];
+      poly1305.update(foo, s1, len).finish(expected_tag, 0);
+      if(!arraysequals(actual_tag, expected_tag)){
+        throw new AEADBadTagException("Tag mismatch");
+      }
+    }
+
+    main_cipher.processBytes(foo, s1+4, len-4, bar, s2+4);
+
+    if(this.mode==ENCRYPT_MODE){
+      poly1305.update(bar, s2, len).finish(bar, len);
+    }
+  }
+  @Override
+  public boolean isCBC(){return false; }
+  @Override
+  public boolean isAEAD(){return true; }
+  @Override
+  public boolean isChaCha20(){return true; }
+
+  private static boolean arraysequals(byte[] a, byte[] b){
+    if(a.length!=b.length) return false;
+    int res=0;
+    for(int i=0; i<a.length; i++){
+      res|=a[i]^b[i];
+    }
+    return res==0;
+  }
+}
diff --git a/src/main/java/com/jcraft/jsch/bc/KeyPairGenEdDSA.java b/src/main/java/com/jcraft/jsch/bc/KeyPairGenEdDSA.java
new file mode 100644
index 00000000..55e806c7
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/bc/KeyPairGenEdDSA.java
@@ -0,0 +1,64 @@
+/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
+/*
+Copyright (c) 2002-2018 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright 
+     notice, this list of conditions and the following disclaimer in 
+     the documentation and/or other materials provided with the distribution.
+
+  3. The names of the authors may not be used to endorse or promote products
+     derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.jcraft.jsch.bc;
+
+import java.security.SecureRandom;
+import org.bouncycastle.crypto.params.*;
+
+public class KeyPairGenEdDSA implements com.jcraft.jsch.KeyPairGenEdDSA{
+  byte[] prv;  // private
+  byte[] pub;  // public
+  int keylen;
+  String name;
+
+  @Override
+  public void init(String name, int keylen) throws Exception{
+    if(!name.equals("Ed25519") && !name.equals("Ed448")){
+      throw new IllegalArgumentException("invalid curve");
+    }
+    this.keylen = keylen;
+    this.name = name;
+
+    if(name.equals("Ed25519")){
+      Ed25519PrivateKeyParameters privateKey = new Ed25519PrivateKeyParameters(new SecureRandom());
+      pub = privateKey.generatePublicKey().getEncoded();
+      prv = privateKey.getEncoded();
+    }
+    else{
+      Ed448PrivateKeyParameters privateKey = new Ed448PrivateKeyParameters(new SecureRandom());
+      pub = privateKey.generatePublicKey().getEncoded();
+      prv = privateKey.getEncoded();
+    }
+  }
+  @Override
+  public byte[] getPrv(){return pub;}
+  @Override
+  public byte[] getPub(){return prv;}
+}
diff --git a/src/main/java/com/jcraft/jsch/bc/SignatureEd25519.java b/src/main/java/com/jcraft/jsch/bc/SignatureEd25519.java
new file mode 100644
index 00000000..feed5a4f
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/bc/SignatureEd25519.java
@@ -0,0 +1,47 @@
+/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
+/*
+Copyright (c) 2015-2018 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright 
+     notice, this list of conditions and the following disclaimer in 
+     the documentation and/or other materials provided with the distribution.
+
+  3. The names of the authors may not be used to endorse or promote products
+     derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.jcraft.jsch.bc;
+
+public class SignatureEd25519 extends SignatureEdDSA {
+  @Override
+  String getName() {
+    return "ssh-ed25519";
+  }
+
+  @Override
+  String getAlgo() {
+    return "Ed25519";
+  }
+
+  @Override
+  int getKeylen() {
+    return 32;
+  }
+}
diff --git a/src/main/java/com/jcraft/jsch/bc/SignatureEd448.java b/src/main/java/com/jcraft/jsch/bc/SignatureEd448.java
new file mode 100644
index 00000000..42cca5e7
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/bc/SignatureEd448.java
@@ -0,0 +1,47 @@
+/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
+/*
+Copyright (c) 2015-2018 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright 
+     notice, this list of conditions and the following disclaimer in 
+     the documentation and/or other materials provided with the distribution.
+
+  3. The names of the authors may not be used to endorse or promote products
+     derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.jcraft.jsch.bc;
+
+public class SignatureEd448 extends SignatureEdDSA {
+  @Override
+  String getName() {
+    return "ssh-ed448";
+  }
+
+  @Override
+  String getAlgo() {
+    return "Ed448";
+  }
+
+  @Override
+  int getKeylen() {
+    return 57;
+  }
+}
diff --git a/src/main/java/com/jcraft/jsch/bc/SignatureEdDSA.java b/src/main/java/com/jcraft/jsch/bc/SignatureEdDSA.java
new file mode 100644
index 00000000..da246393
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/bc/SignatureEdDSA.java
@@ -0,0 +1,114 @@
+/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
+/*
+Copyright (c) 2015-2018 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright 
+     notice, this list of conditions and the following disclaimer in 
+     the documentation and/or other materials provided with the distribution.
+
+  3. The names of the authors may not be used to endorse or promote products
+     derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.jcraft.jsch.bc;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import org.bouncycastle.crypto.Signer;
+import org.bouncycastle.crypto.params.*;
+import org.bouncycastle.crypto.signers.*;
+import com.jcraft.jsch.Buffer;
+
+public abstract class SignatureEdDSA implements com.jcraft.jsch.SignatureEdDSA {
+
+  Signer signature;
+
+  abstract String getName();
+  abstract String getAlgo();
+  abstract int getKeylen();
+
+  @Override
+  public void init() throws Exception{
+    if(!getAlgo().equals("Ed25519") && !getAlgo().equals("Ed448")){
+      throw new IllegalArgumentException("invalid curve");
+    }
+
+    if(getAlgo().equals("Ed25519")){
+      signature = new Ed25519Signer();
+    }
+    else{
+      signature = new Ed448Signer(new byte[0]);
+    }
+  }
+
+  @Override
+  public void setPubKey(byte[] y_arr) throws Exception{
+    if(getAlgo().equals("Ed25519")){
+      Ed25519PublicKeyParameters pubKey = new Ed25519PublicKeyParameters(y_arr);
+      signature.init(false, pubKey);
+    }
+    else{
+      Ed448PublicKeyParameters pubKey = new Ed448PublicKeyParameters(y_arr);
+      signature.init(false, pubKey);
+    }
+  }
+
+  @Override
+  public void setPrvKey(byte[] bytes) throws Exception{
+    if(getAlgo().equals("Ed25519")){
+      Ed25519PrivateKeyParameters prvKey = new Ed25519PrivateKeyParameters(bytes);
+      signature.init(true, prvKey);
+    }
+    else{
+      Ed448PrivateKeyParameters prvKey = new Ed448PrivateKeyParameters(bytes);
+      signature.init(true, prvKey);
+    }
+  }
+
+  @Override
+  public byte[] sign() throws Exception{
+    byte[] sig = signature.generateSignature();
+    return sig;
+  }
+
+  @Override
+  public void update(byte[] foo) throws Exception{
+    signature.update(foo, 0, foo.length);
+  }
+
+  @Override
+  public boolean verify(byte[] sig) throws Exception{
+    int i = 0;
+    int j = 0;
+    byte[] tmp;
+    Buffer buf = new Buffer(sig);
+
+    String foo = new String(buf.getString(), StandardCharsets.UTF_8);
+    if(foo.equals(getName())){
+      j = buf.getInt();
+      i = buf.getOffSet();
+      tmp = new byte[j];
+      System.arraycopy(sig, i, tmp, 0, j);
+      sig = tmp;
+    }
+
+    return signature.verifySignature(sig);
+  }
+}
diff --git a/src/main/java/com/jcraft/jsch/bc/XDH.java b/src/main/java/com/jcraft/jsch/bc/XDH.java
new file mode 100644
index 00000000..7714ea64
--- /dev/null
+++ b/src/main/java/com/jcraft/jsch/bc/XDH.java
@@ -0,0 +1,94 @@
+/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
+/*
+Copyright (c) 2015-2018 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright 
+     notice, this list of conditions and the following disclaimer in 
+     the documentation and/or other materials provided with the distribution.
+
+  3. The names of the authors may not be used to endorse or promote products
+     derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package com.jcraft.jsch.bc;
+
+import java.security.SecureRandom;
+import java.util.Arrays;
+import org.bouncycastle.crypto.params.*;
+
+public class XDH implements com.jcraft.jsch.XDH {
+  byte[] Q_array;
+  Object privateKey;
+  int keylen;
+  String name;
+
+  @Override
+  public void init(String name, int keylen) throws Exception{
+    if(!name.equals("X25519") && !name.equals("X448")){
+      throw new IllegalArgumentException("invalid curve");
+    }
+    this.keylen = keylen;
+    this.name = name;
+    if(name.equals("X25519")){
+      X25519PrivateKeyParameters privateKey = new X25519PrivateKeyParameters(new SecureRandom());
+      Q_array = privateKey.generatePublicKey().getEncoded();
+      this.privateKey = privateKey;
+    }
+    else{
+      X448PrivateKeyParameters privateKey = new X448PrivateKeyParameters(new SecureRandom());
+      Q_array = privateKey.generatePublicKey().getEncoded();
+      this.privateKey = privateKey;
+    }
+  }
+
+  @Override
+  public byte[] getQ() throws Exception{
+    return Q_array;
+  }
+
+  @Override
+  public byte[] getSecret(byte[] Q) throws Exception{
+    byte[] secret = new byte[keylen];
+    if(name.equals("X25519")){
+      X25519PrivateKeyParameters privateKey = (X25519PrivateKeyParameters) this.privateKey;
+      privateKey.generateSecret(new X25519PublicKeyParameters(Q), secret, 0);
+    }
+    else{
+      X448PrivateKeyParameters privateKey = (X448PrivateKeyParameters) this.privateKey;
+      privateKey.generateSecret(new X448PublicKeyParameters(Q), secret, 0);
+    }
+    return secret;
+  }
+
+  // https://cr.yp.to/ecdh.html#validate
+  // RFC 8731,
+  // 3. Key Exchange Methods
+  //   Clients and servers MUST
+  //   also abort if the length of the received public keys are not the
+  //   expected lengths.  An abort for these purposes is defined as a
+  //   disconnect (SSH_MSG_DISCONNECT) of the session and SHOULD use the
+  //   SSH_DISCONNECT_KEY_EXCHANGE_FAILED reason for the message
+  //   [IANA-REASON].  No further validation is required beyond what is
+  //   described in [RFC7748].
+  @Override
+  public boolean validate(byte[] u) throws Exception{
+    return u.length == keylen;
+  }
+}
diff --git a/src/main/java11/com/jcraft/jsch/jce/ChaCha20Poly1305.java b/src/main/java11/com/jcraft/jsch/jce/ChaCha20Poly1305.java
index 4eda0542..10c6addf 100644
--- a/src/main/java11/com/jcraft/jsch/jce/ChaCha20Poly1305.java
+++ b/src/main/java11/com/jcraft/jsch/jce/ChaCha20Poly1305.java
@@ -32,7 +32,6 @@ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 import com.jcraft.jsch.Cipher;
 import com.jcraft.jsch.openjax.Poly1305;
 import java.nio.ByteBuffer;
-import java.util.Arrays;
 import javax.crypto.AEADBadTagException;
 import javax.crypto.spec.*;
 
diff --git a/src/main/java11/com/jcraft/jsch/jce/KeyPairGenXEC.java b/src/main/java11/com/jcraft/jsch/jce/KeyPairGenXEC.java
index 0fd2363f..6ffe2663 100644
--- a/src/main/java11/com/jcraft/jsch/jce/KeyPairGenXEC.java
+++ b/src/main/java11/com/jcraft/jsch/jce/KeyPairGenXEC.java
@@ -32,7 +32,6 @@ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 import java.security.*;
 import java.security.interfaces.*;
 import java.security.spec.*;
-import com.jcraft.jsch.JSchException;
 
 public class KeyPairGenXEC implements com.jcraft.jsch.KeyPairGenXEC {
   XECPublicKey pubKey;
diff --git a/src/main/java9/com/jcraft/jsch/JavaVersion.java b/src/main/java9/com/jcraft/jsch/JavaVersion.java
new file mode 100644
index 00000000..c3f8afb3
--- /dev/null
+++ b/src/main/java9/com/jcraft/jsch/JavaVersion.java
@@ -0,0 +1,8 @@
+package com.jcraft.jsch;
+
+final class JavaVersion {
+
+  static int getVersion() {
+    return Runtime.version().major();
+  }
+}
diff --git a/src/main/java9/module-info.java b/src/main/java9/module-info.java
index e4960c2a..4d3fe604 100644
--- a/src/main/java9/module-info.java
+++ b/src/main/java9/module-info.java
@@ -2,6 +2,7 @@
     exports com.jcraft.jsch;
 
     requires java.security.jgss;
+    requires static org.bouncycastle.provider;
     requires static org.newsclub.net.unix;
     requires static com.kohlschutter.junixsocket.nativecommon;
     requires static com.sun.jna;
diff --git a/src/test/java/com/jcraft/jsch/Algorithms2IT.java b/src/test/java/com/jcraft/jsch/Algorithms2IT.java
index 15146761..710a917b 100644
--- a/src/test/java/com/jcraft/jsch/Algorithms2IT.java
+++ b/src/test/java/com/jcraft/jsch/Algorithms2IT.java
@@ -121,6 +121,19 @@ public void afterEach() {
   public void testJava11KEXs() throws Exception {
     JSch ssh = createRSAIdentity();
     Session session = createSession(ssh);
+    session.setConfig("xdh", "com.jcraft.jsch.jce.XDH");
+    session.setConfig("kex", "curve448-sha512");
+    doSftp(session, true);
+
+    String expected = "kex: algorithm: curve448-sha512.*";
+    checkLogs(expected);
+  }
+
+  @Test
+  public void testBCKEXs() throws Exception {
+    JSch ssh = createRSAIdentity();
+    Session session = createSession(ssh);
+    session.setConfig("xdh", "com.jcraft.jsch.bc.XDH");
     session.setConfig("kex", "curve448-sha512");
     doSftp(session, true);
 
@@ -192,9 +205,25 @@ public void testDHGEXSizes(String kex, String size) throws Exception {
 
   @Test
   @EnabledForJreRange(min = JAVA_15)
-  public void testEd448() throws Exception {
+  public void testJava15Ed448() throws Exception {
+    JSch ssh = createEd448Identity();
+    Session session = createSession(ssh);
+    session.setConfig("keypairgen.eddsa", "com.jcraft.jsch.jce.KeyPairGenEdDSA");
+    session.setConfig("ssh-ed448", "com.jcraft.jsch.jce.SignatureEd448");
+    session.setConfig("PubkeyAcceptedAlgorithms", "ssh-ed448");
+    session.setConfig("server_host_key", "ssh-ed448");
+    doSftp(session, true);
+
+    String expected = "kex: host key algorithm: ssh-ed448.*";
+    checkLogs(expected);
+  }
+
+  @Test
+  public void testBCEd448() throws Exception {
     JSch ssh = createEd448Identity();
     Session session = createSession(ssh);
+    session.setConfig("keypairgen.eddsa", "com.jcraft.jsch.bc.KeyPairGenEdDSA");
+    session.setConfig("ssh-ed448", "com.jcraft.jsch.bc.SignatureEd448");
     session.setConfig("PubkeyAcceptedAlgorithms", "ssh-ed448");
     session.setConfig("server_host_key", "ssh-ed448");
     doSftp(session, true);
diff --git a/src/test/java/com/jcraft/jsch/AlgorithmsIT.java b/src/test/java/com/jcraft/jsch/AlgorithmsIT.java
index 141d7172..37ae5160 100644
--- a/src/test/java/com/jcraft/jsch/AlgorithmsIT.java
+++ b/src/test/java/com/jcraft/jsch/AlgorithmsIT.java
@@ -121,6 +121,20 @@ public void afterEach() {
   public void testJava11KEXs(String kex) throws Exception {
     JSch ssh = createRSAIdentity();
     Session session = createSession(ssh);
+    session.setConfig("xdh", "com.jcraft.jsch.jce.XDH");
+    session.setConfig("kex", kex);
+    doSftp(session, true);
+
+    String expected = String.format("kex: algorithm: %s.*", kex);
+    checkLogs(expected);
+  }
+
+  @ParameterizedTest
+  @ValueSource(strings = {"curve25519-sha256", "curve25519-sha256@libssh.org"})
+  public void testBCKEXs(String kex) throws Exception {
+    JSch ssh = createRSAIdentity();
+    Session session = createSession(ssh);
+    session.setConfig("xdh", "com.jcraft.jsch.bc.XDH");
     session.setConfig("kex", kex);
     doSftp(session, true);
 
@@ -183,9 +197,25 @@ public void testDHGEXSizes(String kex, String size) throws Exception {
 
   @Test
   @EnabledForJreRange(min = JAVA_15)
-  public void testEd25519() throws Exception {
+  public void testJava15Ed25519() throws Exception {
+    JSch ssh = createEd25519Identity();
+    Session session = createSession(ssh);
+    session.setConfig("keypairgen.eddsa", "com.jcraft.jsch.jce.KeyPairGenEdDSA");
+    session.setConfig("ssh-ed25519", "com.jcraft.jsch.jce.SignatureEd25519");
+    session.setConfig("PubkeyAcceptedAlgorithms", "ssh-ed25519");
+    session.setConfig("server_host_key", "ssh-ed25519");
+    doSftp(session, true);
+
+    String expected = "kex: host key algorithm: ssh-ed25519.*";
+    checkLogs(expected);
+  }
+
+  @Test
+  public void testBCEd25519() throws Exception {
     JSch ssh = createEd25519Identity();
     Session session = createSession(ssh);
+    session.setConfig("keypairgen.eddsa", "com.jcraft.jsch.bc.KeyPairGenEdDSA");
+    session.setConfig("ssh-ed25519", "com.jcraft.jsch.bc.SignatureEd25519");
     session.setConfig("PubkeyAcceptedAlgorithms", "ssh-ed25519");
     session.setConfig("server_host_key", "ssh-ed25519");
     doSftp(session, true);
@@ -265,6 +295,29 @@ public void testDSA() throws Exception {
   public void testJava11Ciphers(String cipher, String compression) throws Exception {
     JSch ssh = createRSAIdentity();
     Session session = createSession(ssh);
+    session.setConfig("chacha20-poly1305@openssh.com", "com.jcraft.jsch.jce.ChaCha20Poly1305");
+    session.setConfig("cipher.s2c", cipher);
+    session.setConfig("cipher.c2s", cipher);
+    session.setConfig("compression.s2c", compression);
+    session.setConfig("compression.c2s", compression);
+    doSftp(session, true);
+
+    String expectedS2C = String.format("kex: server->client cipher: %s.*", cipher);
+    String expectedC2S = String.format("kex: client->server cipher: %s.*", cipher);
+    checkLogs(expectedS2C);
+    checkLogs(expectedC2S);
+  }
+
+  @ParameterizedTest
+  @CsvSource(
+      value = {
+        "chacha20-poly1305@openssh.com,none",
+        "chacha20-poly1305@openssh.com,zlib@openssh.com"
+      })
+  public void testBCCiphers(String cipher, String compression) throws Exception {
+    JSch ssh = createRSAIdentity();
+    Session session = createSession(ssh);
+    session.setConfig("chacha20-poly1305@openssh.com", "com.jcraft.jsch.bc.ChaCha20Poly1305");
     session.setConfig("cipher.s2c", cipher);
     session.setConfig("cipher.c2s", cipher);
     session.setConfig("compression.s2c", compression);