diff --git a/core/java/src/net/i2p/crypto/x25519/X25519DH.java b/core/java/src/net/i2p/crypto/x25519/X25519DH.java
new file mode 100644
index 000000000..3436032b4
--- /dev/null
+++ b/core/java/src/net/i2p/crypto/x25519/X25519DH.java
@@ -0,0 +1,34 @@
+package net.i2p.crypto.x25519;
+
+import com.southernstorm.noise.crypto.x25519.Curve25519;
+
+import net.i2p.crypto.EncType;
+import net.i2p.data.PrivateKey;
+import net.i2p.data.PublicKey;
+import net.i2p.data.SessionKey;
+
+/**
+ * DH wrapper around Noise's Curve25519 with I2P types.
+ *
+ * @since 0.9.41
+ */
+public class X25519DH {
+
+ private static final EncType TYPE = EncType.ECIES_X25519;
+
+ private X25519DH() {}
+
+ /**
+ * DH
+ *
+ * @return ECIES_X25519
+ * @throws IllegalArgumentException if not ECIES_X25519
+ */
+ public static SessionKey dh(PrivateKey priv, PublicKey pub) {
+ if (priv.getType() != TYPE || pub.getType() != TYPE)
+ throw new IllegalArgumentException();
+ byte[] rv = new byte[32];
+ Curve25519.eval(rv, 0, priv.getData(), pub.getData());
+ return new SessionKey(rv);
+ }
+}
diff --git a/core/java/src/net/i2p/crypto/x25519/package.html b/core/java/src/net/i2p/crypto/x25519/package.html
new file mode 100644
index 000000000..286c605d8
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+++ b/core/java/src/net/i2p/crypto/x25519/package.html
@@ -0,0 +1,7 @@
+
+
+ DH for X25519.
+
+ Since 0.9.41.
+
+