diff --git a/src/crypto.rs b/src/crypto.rs
index 39e1190..5f16cdf 100644
--- a/src/crypto.rs
+++ b/src/crypto.rs
@@ -14,21 +14,21 @@ use x25519_dalek::{EphemeralSecret, PublicKey, SharedSecret};
 
 const AES_NONCE_SIZE: usize = 12;
 
-async fn ephemeral_dh(
+pub async fn edh(
     reader: &mut BufReader<ReadHalf<'_>>,
     writer: &mut BufWriter<WriteHalf<'_>>,
     buf: &mut Vec<u8>,
     go_first: bool,
-) -> Result<SharedSecret, Box<dyn Error>> {
+) -> Result<SharedSecret, Box<dyn Error + Send + Sync>> {
     let own_sec = EphemeralSecret::new(OsRng);
     let own_pbk = PublicKey::from(&own_sec);
 
     if go_first {
-        comms::send_bytes(writer, own_pbk.as_bytes()).await?;
-        comms::recv_bytes(reader, buf).await?;
+        comms::send_bytes(writer, None, &own_pbk.as_bytes().to_vec()).await?;
+        comms::recv_bytes(reader, None, buf).await?;
     } else {
-        comms::recv_bytes(reader, buf).await?;
-        comms::send_bytes(writer, own_pbk.as_bytes()).await?;
+        comms::recv_bytes(reader, None, buf).await?;
+        comms::send_bytes(writer, None, &own_pbk.as_bytes().to_vec()).await?;
     }
 
     let sliced_buf: [u8; 32] = buf[..32].try_into()?;
@@ -37,7 +37,9 @@ async fn ephemeral_dh(
     Ok(own_sec.diffie_hellman(&recv_pbk))
 }
 
-fn aes_cipher(secret: SharedSecret) -> Result<AesGcm<Aes256, U12>, Box<dyn Error>> {
+pub fn aes_cipher(
+    secret: SharedSecret,
+) -> Result<AesGcm<Aes256, U12>, Box<dyn Error + Sync + Send>> {
     Ok(Aes256Gcm::new(secret.as_bytes().into()))
 }
 
@@ -47,21 +49,20 @@ fn generate_nonce(rng: &mut impl RngCore) -> Nonce<U12> {
     nonce
 }
 
-fn aes_encrypt(
-    data: Vec<u8>,
+pub fn aes_encrypt(
+    data: &Vec<u8>,
     cipher: &mut AesGcm<Aes256, U12>,
-    rng: &mut impl RngCore,
-) -> Result<Vec<u8>, Box<dyn Error>> {
+    rng: &mut OsRng,
+) -> Result<Vec<u8>, Box<dyn Error + Send + Sync>> {
     let nonce = generate_nonce(rng);
     let encrypted = cipher.encrypt(&nonce, data.as_ref()).unwrap(); // TODO: handle error types
     Ok(encrypted)
 }
 
-fn aes_decrypt(
-    data: Vec<u8>,
+pub fn aes_decrypt(
+    data: &Vec<u8>,
     cipher: &mut AesGcm<Aes256, U12>,
-    rng: &mut impl RngCore,
-) -> Result<Vec<u8>, Box<dyn Error>> {
+) -> Result<Vec<u8>, Box<dyn Error + Send + Sync>> {
     let (nonce_bytes, data) = data.split_at(AES_NONCE_SIZE);
     let decrypted = cipher
         .decrypt(Nonce::from_slice(nonce_bytes), data.as_ref())