Migrate to thiserror v2. Error handling improvements.

Author: wolfmcnally

Cargo.toml

@@ -15,7 +15,7 @@ categories = ["cryptography"]                                      # https://cra
 bc-rand = "^0.4.0"
 bc-crypto = "^0.9.0"
 
-thiserror = "^1.0.48"
+thiserror = "^2.0"
 
 [dev-dependencies]
 hex-literal = "^0.4.1"

src/error.rs

@@ -26,3 +26,5 @@ pub enum Error {
     #[error("shares have unequal length")]
     SharesUnequalLength,
 }
+
+pub type Result<T> = std::result::Result<T, Error>;

src/interpolate.rs

@@ -1,6 +1,6 @@
 use crate::{
     hazmat::{bitslice, bitslice_setall, gf256_add, gf256_mul, gf256_inv, unbitslice},
-    Error, MAX_SECRET_LEN
+    Result, MAX_SECRET_LEN
 };
 use bc_crypto::{memzero, memzero_vec_vec_u8};
 
@@ -103,7 +103,7 @@ pub fn interpolate<T>(
     yl: usize,
     yij: &[T],
     x: u8
-) -> Result<Vec<u8>, Error>
+) -> Result<Vec<u8>>
 where
     T: AsRef<[u8]>
 {

src/lib.rs

@@ -67,7 +67,7 @@ mod hazmat;
 mod interpolate;
 
 mod error;
-pub use error::Error;
+pub use error::{Error, Result};
 
 mod shamir;
 pub use shamir::{ recover_secret, split_secret };
@@ -95,7 +95,7 @@ mod tests {
             unimplemented!()
         }
 
-        fn try_fill_bytes(&mut self, _dest: &mut [u8]) -> Result<(), rand::Error> {
+        fn try_fill_bytes(&mut self, _dest: &mut [u8]) -> std::result::Result<(), rand::Error> {
             unimplemented!()
         }
     }

src/shamir.rs

@@ -6,6 +6,7 @@ use crate::{
     MAX_SECRET_LEN,
     MIN_SECRET_LEN,
     Error,
+    Result,
     interpolate::interpolate,
 };
 
@@ -16,7 +17,7 @@ fn create_digest(random_data: &[u8], shared_secret: &[u8]) -> [u8; 32] {
     hmac_sha256(random_data, shared_secret)
 }
 
-fn validate_parameters(threshold: usize, share_count: usize, secret_length: usize) -> Result<(), Error> {
+fn validate_parameters(threshold: usize, share_count: usize, secret_length: usize) -> Result<()> {
     if share_count > MAX_SHARE_COUNT {
         return Err(Error::TooManyShares);
     } else if threshold < 1 || threshold > share_count {
@@ -73,7 +74,7 @@ pub fn split_secret(
     share_count: usize,
     secret: &[u8],
     random_generator: &mut impl RandomNumberGenerator
-) -> Result<Vec<Vec<u8>>, Error> {
+) -> Result<Vec<Vec<u8>>> {
     validate_parameters(threshold, share_count, secret.len())?;
 
     if threshold == 1 {
@@ -158,7 +159,7 @@ pub fn split_secret(
 ///
 /// assert_eq!(secret, b"my secret belongs to me.");
 /// ```
-pub fn recover_secret<T>(indexes: &[usize], shares: &[T]) -> Result<Vec<u8>, Error>
+pub fn recover_secret<T>(indexes: &[usize], shares: &[T]) -> Result<Vec<u8>>
     where T: AsRef<[u8]>
 {
     let threshold = shares.len();