Adding expand_message_xmd and RFC compliance with VOPRF and H2C (#80)

src/serialization/tests.rs

@@ -13,7 +13,7 @@ use crate::{
     },
     keypair::{KeyPair, X25519KeyPair},
     opaque::*,
-    serialization::{serialize, ProtocolMessageType},
+    serialization::{i2osp, os2ip, serialize, ProtocolMessageType},
 };
 
 use curve25519_dalek::ristretto::RistrettoPoint;
@@ -240,7 +240,7 @@ fn login_second_message_roundtrip() {
 
     let ke2m: Vec<u8> = [&server_nonce[..], &server_e_kp.public(), &mac[..]].concat();
 
-    let total_length_without_ke2m: usize = pt_bytes.len() + envelope.to_bytes().len() + 2;
+    let total_length_without_ke2m = pt_bytes.len() + envelope.to_bytes().len() + 2;
 
     let mut input = Vec::new();
     input.extend_from_slice(&[ProtocolMessageType::CredentialResponse as u8 + 1]);
@@ -312,6 +312,11 @@ fn ke1_message_roundtrip() {
 
 proptest! {
 
+#[test]
+fn test_i2osp_os2ip(bytes in vec(any::<u8>(), 0..std::mem::size_of::<usize>())) {
+    assert_eq!(i2osp(os2ip(&bytes)?, bytes.len()), bytes);
+}
+
 #[test]
 fn test_nocrash_register_first_message(bytes in vec(any::<u8>(), 0..200)) {
     RegisterFirstMessage::<RistrettoPoint>::try_from(&bytes[..]).map_or(true, |_| true);