diff --git a/lib/bcoin/chachapoly.js b/lib/bcoin/chachapoly.js
index d595c6e5..f36b79e7 100644
--- a/lib/bcoin/chachapoly.js
+++ b/lib/bcoin/chachapoly.js
@@ -110,6 +110,8 @@ ChaCha20.prototype.encrypt = function encrypt(data) {
 
     data[i] ^= this.bytes[this.pos++];
   }
+
+  return data;
 };
 
 /**
@@ -529,6 +531,8 @@ AEAD.prototype.encrypt = function encrypt(data) {
   this.chacha20.encrypt(data);
   this.poly1305.update(data);
   this.cipherLen += data.length;
+
+  return data;
 };
 
 /**
@@ -543,6 +547,8 @@ AEAD.prototype.decrypt = function decrypt(data) {
   this.cipherLen += data.length;
   this.poly1305.update(data);
   this.chacha20.encrypt(data);
+
+  return data;
 };
 
 /**
diff --git a/lib/bcoin/ec.js b/lib/bcoin/ec.js
index 7fa8c20d..d9ebbbca 100644
--- a/lib/bcoin/ec.js
+++ b/lib/bcoin/ec.js
@@ -86,6 +86,23 @@ ec.publicKeyCreate = function publicKeyCreate(priv, compressed) {
   return new Buffer(priv);
 };
 
+/**
+ * Create an ecdh.
+ * @param {Buffer} pub
+ * @param {Buffer} priv
+ * @returns {Buffer}
+ */
+
+ec.ecdh = function ecdh(pub, priv) {
+  if (secp256k1)
+    return secp256k1.ecdh(pub, priv);
+
+  priv = ec.elliptic.keyPair({ priv: priv });
+  pub = ec.elliptic.keyPair({ pub: pub });
+
+  return priv.derive(pub.getPublic()).toArrayLike(Buffer, 'be', 32);
+};
+
 /**
  * Generate some random bytes.
  * @param {Number} size