diff --git a/src/crypto.rs b/src/crypto.rs
index c14b7b1..fc1c853 100644
--- a/src/crypto.rs
+++ b/src/crypto.rs
@@ -4,7 +4,7 @@ use anyhow::{Error, Result};
 use serde::{Deserialize, Serialize};
 use sp_client::{
     bitcoin::{
-        hex::{DisplayHex, FromHex}, key::constants::SECRET_KEY_SIZE, secp256k1::{ecdh::SharedSecret, PublicKey}, Txid
+        hex::{DisplayHex, FromHex}, key::constants::SECRET_KEY_SIZE, Txid
     },
     silentpayments::{
         bitcoin_hashes::{sha256t_hash_newtype, Hash, HashEngine},
@@ -13,20 +13,12 @@ use sp_client::{
 };
 use tsify::Tsify;
 
-use aes_gcm::{
-    aead::{Aead, AeadInPlace, Nonce},
-    aes::{
-        cipher::{
-            consts::{U32, U8},
-            generic_array::GenericArray,
-        },
-        Aes256,
-    },
-    AesGcm, Key, TagSize,
-};
+use aes_gcm::aead::{Aead, Payload};
 pub use aes_gcm::{AeadCore, Aes256Gcm, KeyInit};
 use rand::thread_rng;
 
+const AAD: &[u8] = "4nk".as_bytes();
+
 const HALFKEYSIZE: usize = SECRET_KEY_SIZE / 2;
 
 const THIRTYTWO: usize = 32;
@@ -40,7 +32,7 @@ impl SharedPoint {
     }
 }
 
-#[derive(Debug, Serialize, Deserialize, Tsify, Clone)]
+#[derive(Debug, Serialize, Deserialize, Tsify, Clone, Default, PartialEq)]
 #[tsify(from_wasm_abi, into_wasm_abi)]
 pub struct AnkSharedSecret {
     secret: String,
@@ -183,8 +175,12 @@ impl Aes256Decryption {
 
     fn decrypt_arbitrary(&self) -> Result<Vec<u8>> {
         let cipher = Aes256Gcm::new(&self.aes_key.into());
+        let payload = Payload {
+            msg: &self.cipher_text,
+            aad: AAD,
+        };
         let plain = cipher
-            .decrypt(&self.nonce.into(), &*self.cipher_text)
+            .decrypt(&self.nonce.into(), payload)
             .map_err(|e| Error::msg(format!("{}", e)))?;
         Ok(plain)
     }
@@ -294,8 +290,12 @@ impl Aes256Encryption {
 
     fn encrypt_arbitrary(&self) -> Result<CipherText> {
         let cipher = Aes256Gcm::new(&self.aes_key.into());
+        let payload = Payload {
+            msg: &self.plaintext,
+            aad: AAD,
+        };
         let cipher_text = cipher
-            .encrypt(&self.nonce.into(), &*self.plaintext)
+            .encrypt(&self.nonce.into(), payload)
             .map_err(|e| Error::msg(format!("{}", e)))?;
         let mut res = Vec::with_capacity(self.nonce.len() + cipher_text.len());
         res.extend_from_slice(&self.nonce);
@@ -375,137 +375,4 @@ mod tests {
 
         assert!(aes_dec.is_ok());
     }
-
-    #[test]
-    fn aes_encrypt_key() {
-        let plaintext = [1u8; HALFKEYSIZE];
-        let mut aes_enc = Aes256Encryption::new(Purpose::Login, plaintext.to_vec()).unwrap();
-
-        let mut shared_secrets: HashMap<Txid, _> = HashMap::new();
-        let mut sp_address2shared_secrets: HashMap<SilentPaymentAddress, AnkSharedSecret> =
-            HashMap::new();
-        let alice_secret = Vec::from_hex(ALICE_SHARED_SECRET).unwrap();
-        let mut buf = [0u8;32];
-        buf.copy_from_slice(&alice_secret);
-        sp_address2shared_secrets.insert(
-            ALICE_SP_ADDRESS.try_into().unwrap(),
-            AnkSharedSecret { secret: buf.to_lower_hex_string(), trusted: true }
-        );
-        shared_secrets.insert(
-            Txid::from_str(TRANSACTION).unwrap(),
-            sp_address2shared_secrets,
-        );
-
-        aes_enc.set_shared_secret(shared_secrets);
-
-        let sp_address2encrypted_keys = aes_enc.encrypt_keys_with_shared_secrets();
-
-        assert!(sp_address2encrypted_keys.is_ok());
-
-        let encrypted_key = sp_address2encrypted_keys
-            .unwrap()
-            .get(&ALICE_SP_ADDRESS.try_into().unwrap())
-            .cloned();
-
-        let ciphertext = aes_enc.encrypt_with_aes_key();
-
-        assert!(ciphertext.is_ok());
-
-        let decrypt_key = Aes256Decryption::new(
-            Purpose::Arbitrary,
-            encrypted_key.unwrap(),
-            SharedSecret::from_str(ALICE_SHARED_SECRET).unwrap().secret_bytes(),
-        );
-
-        assert!(decrypt_key.is_ok());
-
-        let mut retrieved_key = [0u8;32];
-        retrieved_key.copy_from_slice(&decrypt_key.unwrap().decrypt_with_key().unwrap());
-
-        let decrypt_msg = Aes256Decryption::new(
-            Purpose::Arbitrary,
-            ciphertext.unwrap(),
-            retrieved_key
-        );
-
-        let retrieved_plain = decrypt_msg.unwrap().decrypt_with_key();
-
-        assert!(retrieved_plain.is_ok());
-
-        assert!(retrieved_plain.unwrap() == plaintext);
-    }
-
-//     #[test]
-//     fn aes_encrypt_key_many() {
-//         let plaintext = [1u8; THIRTYTWO];
-//         let mut aes_enc =
-//             Aes256Encryption::new(Purpose::ThirtyTwoBytes, plaintext.to_vec()).unwrap();
-
-//         let mut shared_secrets: HashMap<Txid, _> = HashMap::new();
-//         let mut sp_address2shared_secrets: HashMap<SilentPaymentAddress, AnkSharedSecret> =
-//             HashMap::new();
-//         let alice_secret = Vec::from_hex(ALICE_SHARED_SECRET).unwrap();
-//         let mut buf = [0u8;32];
-//         buf.copy_from_slice(&alice_secret);
-//         sp_address2shared_secrets.insert(
-//             ALICE_SP_ADDRESS.try_into().unwrap(),
-//             AnkSharedSecret { secret: buf, trusted: true }
-//         );
-//         let bob_secret = Vec::from_hex(BOB_SHARED_SECRET).unwrap();
-//         let mut buf = [0u8;32];
-//         buf.copy_from_slice(&bob_secret);
-//         sp_address2shared_secrets.insert(
-//             BOB_SP_ADDRESS.try_into().unwrap(),
-//             AnkSharedSecret { secret: buf, trusted: true }
-//         );
-//         shared_secrets.insert(
-//             Txid::from_str(TRANSACTION).unwrap(),
-//             sp_address2shared_secrets,
-//         );
-
-//         aes_enc.set_shared_secret(shared_secrets);
-
-//         let mut sp_address2encrypted_keys = aes_enc.encrypt_keys_with_shared_secrets();
-
-//         assert!(sp_address2encrypted_keys.is_ok());
-
-//         // Alice
-//         let encrypted_key = sp_address2encrypted_keys
-//             .as_mut()
-//             .unwrap()
-//             .get(&ALICE_SP_ADDRESS.try_into().unwrap())
-//             .cloned();
-
-//         let ciphertext = aes_enc.encrypt_with_aes_key();
-
-//         let aes_dec = Aes256Decryption::new(
-//             Purpose::ThirtyTwoBytes,
-//             ciphertext.unwrap(),
-//             encrypted_key.unwrap(),
-//             Some(SharedSecret::from_str(ALICE_SHARED_SECRET).unwrap()),
-//         );
-
-//         let retrieved_plain = aes_dec.unwrap().decrypt_with_key();
-
-//         assert!(retrieved_plain.unwrap() == plaintext);
-
-//         // Bob
-//         let encrypted_key = sp_address2encrypted_keys
-//             .unwrap()
-//             .get(&BOB_SP_ADDRESS.try_into().unwrap())
-//             .cloned();
-
-//         let ciphertext = aes_enc.encrypt_with_aes_key();
-
-//         let aes_dec = Aes256Decryption::new(
-//             Purpose::ThirtyTwoBytes,
-//             ciphertext.unwrap(),
-//             encrypted_key.unwrap(),
-//             Some(SharedSecret::from_str(BOB_SHARED_SECRET).unwrap()),
-//         );
-
-//         let retrieved_plain = aes_dec.unwrap().decrypt_with_key();
-
-//         assert!(retrieved_plain.unwrap() == plaintext);
-//     }
 }