Simplifying error handling (#232)

src/serialization/mod.rs

@@ -3,16 +3,16 @@
 // This source code is licensed under the MIT license found in the
 // LICENSE file in the root directory of this source tree.
 
-use crate::errors::PakeError;
+use crate::errors::ProtocolError;
 use alloc::vec::Vec;
 
 // Corresponds to the I2OSP() function from RFC8017
-pub(crate) fn i2osp(input: usize, length: usize) -> Result<alloc::vec::Vec<u8>, PakeError> {
+pub(crate) fn i2osp(input: usize, length: usize) -> Result<alloc::vec::Vec<u8>, ProtocolError> {
     let sizeof_usize = core::mem::size_of::<usize>();
 
     // Check if input >= 256^length
     if (sizeof_usize as u32 - input.leading_zeros() / 8) > length as u32 {
-        return Err(PakeError::SerializationError);
+        return Err(ProtocolError::SerializationError);
     }
 
     if length <= sizeof_usize {
@@ -28,9 +28,9 @@ pub(crate) fn i2osp(input: usize, length: usize) -> Result<alloc::vec::Vec<u8>,
 }
 
 // Corresponds to the OS2IP() function from RFC8017
-pub(crate) fn os2ip(input: &[u8]) -> Result<usize, PakeError> {
+pub(crate) fn os2ip(input: &[u8]) -> Result<usize, ProtocolError> {
     if input.len() > core::mem::size_of::<usize>() {
-        return Err(PakeError::SerializationError);
+        return Err(ProtocolError::SerializationError);
     }
 
     let mut output_array = [0u8; core::mem::size_of::<usize>()];
@@ -39,20 +39,23 @@ pub(crate) fn os2ip(input: &[u8]) -> Result<usize, PakeError> {
 }
 
 // Computes I2OSP(len(input), max_bytes) || input
-pub(crate) fn serialize(input: &[u8], max_bytes: usize) -> Result<Vec<u8>, PakeError> {
+pub(crate) fn serialize(input: &[u8], max_bytes: usize) -> Result<Vec<u8>, ProtocolError> {
     Ok([&i2osp(input.len(), max_bytes)?, input].concat())
 }
 
 // Tokenizes an input of the format I2OSP(len(input), max_bytes) || input, outputting
 // (input, remainder)
-pub(crate) fn tokenize(input: &[u8], size_bytes: usize) -> Result<(Vec<u8>, Vec<u8>), PakeError> {
+pub(crate) fn tokenize(
+    input: &[u8],
+    size_bytes: usize,
+) -> Result<(Vec<u8>, Vec<u8>), ProtocolError> {
     if size_bytes > core::mem::size_of::<usize>() || input.len() < size_bytes {
-        return Err(PakeError::SerializationError);
+        return Err(ProtocolError::SerializationError);
     }
 
     let size = os2ip(&input[..size_bytes])?;
     if size_bytes + size > input.len() {
-        return Err(PakeError::SerializationError);
+        return Err(ProtocolError::SerializationError);
     }
 
     Ok((