Replace the apparently unmaintained hex crate with data-encoding

data-encoding was already a transitive dependency via tungstenite

Cargo.lock

@@ -389,9 +389,9 @@ checksum = "0c87e182de0887fd5361989c677c4e8f5000cd9491d6d563161a8f3a5519fc7f"
 
 [[package]]
 name = "data-encoding"
-version = "2.4.0"
+version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c2e66c9d817f1720209181c316d28635c050fa304f9c79e47a520882661b7308"
+checksum = "7e962a19be5cfc3f3bf6dd8f61eb50107f356ad6270fbb3ed41476571db78be5"
 
 [[package]]
 name = "der"
@@ -1331,10 +1331,10 @@ dependencies = [
 name = "librespot"
 version = "0.5.0-dev"
 dependencies = [
+ "data-encoding",
  "env_logger",
  "futures-util",
  "getopts",
- "hex",
  "librespot-audio",
  "librespot-connect",
  "librespot-core",
@@ -1398,13 +1398,13 @@ dependencies = [
  "base64 0.21.5",
  "byteorder",
  "bytes",
+ "data-encoding",
  "dns-sd",
  "env_logger",
  "form_urlencoded",
  "futures-core",
  "futures-util",
  "governor",
- "hex",
  "hmac",
  "http",
  "httparse",

Cargo.toml

@@ -50,10 +50,10 @@ path = "protocol"
 version = "0.5.0-dev"
 
 [dependencies]
+data-encoding = "2.5"
 env_logger =  { version = "0.10", default-features = false, features = ["color", "humantime", "auto-color"] }
 futures-util = { version = "0.3", default_features = false }
 getopts = "0.2"
-hex = "0.4"
 log = "0.4"
 rpassword = "7.0"
 sha1 = "0.10"

core/Cargo.toml

@@ -23,7 +23,6 @@ form_urlencoded = "1.0"
 futures-core = "0.3"
 futures-util = { version = "0.3", features = ["alloc", "bilock", "sink", "unstable"] }
 governor = { version = "0.6", default-features = false, features = ["std", "jitter"] }
-hex = "0.4"
 hmac = "0.12"
 httparse = "1.7"
 http = "0.2"
@@ -57,6 +56,7 @@ tokio-tungstenite = { version = "*", default-features = false, features = ["rust
 tokio-util = { version = "0.7", features = ["codec"] }
 url = "2"
 uuid = { version = "1", default-features = false, features = ["fast-rng", "v4"] }
+data-encoding = "2.5"
 
 [build-dependencies]
 rand = "0.8"

core/src/spclient.rs

@@ -6,6 +6,7 @@ use std::{
 
 use byteorder::{BigEndian, ByteOrder};
 use bytes::Bytes;
+use data_encoding::HEXUPPER_PERMISSIVE;
 use futures_util::future::IntoStream;
 use http::header::HeaderValue;
 use hyper::{
@@ -279,20 +280,22 @@ impl SpClient {
                         let hash_cash_challenge = challenge.evaluate_hashcash_parameters();
 
                         let ctx = vec![];
-                        let prefix = hex::decode(&hash_cash_challenge.prefix).map_err(|e| {
+                        let prefix = HEXUPPER_PERMISSIVE
+                            .decode(hash_cash_challenge.prefix.as_bytes())
+                            .map_err(|e| {
                                 Error::failed_precondition(format!(
                                     "Unable to decode hash cash challenge: {e}"
                                 ))
                             })?;
                         let length = hash_cash_challenge.length;
 
-                        let mut suffix = vec![0; 0x10];
+                        let mut suffix = [0u8; 0x10];
                         let answer = Self::solve_hash_cash(&ctx, &prefix, length, &mut suffix);
 
                         match answer {
                             Ok(_) => {
                                 // the suffix must be in uppercase
-                                let suffix = hex::encode(suffix).to_uppercase();
+                                let suffix = HEXUPPER_PERMISSIVE.encode(&suffix);
 
                                 let mut answer_message = ClientTokenRequest::new();
                                 answer_message.request_type =
@@ -302,7 +305,7 @@ impl SpClient {
                                 let challenge_answers = answer_message.mut_challenge_answers();
 
                                 let mut challenge_answer = ChallengeAnswer::new();
-                                challenge_answer.mut_hash_cash().suffix = suffix.to_string();
+                                challenge_answer.mut_hash_cash().suffix = suffix;
                                 challenge_answer.ChallengeType =
                                     ChallengeType::CHALLENGE_HASH_CASH.into();
 

src/main.rs

@@ -1,3 +1,4 @@
+use data_encoding::HEXLOWER;
 use futures_util::StreamExt;
 use log::{debug, error, info, trace, warn};
 use sha1::{Digest, Sha1};
@@ -39,7 +40,7 @@ mod player_event_handler;
 use player_event_handler::{run_program_on_sink_events, EventHandler};
 
 fn device_id(name: &str) -> String {
-    hex::encode(Sha1::digest(name.as_bytes()))
+    HEXLOWER.encode(&Sha1::digest(name.as_bytes()))
 }
 
 fn usage(program: &str, opts: &getopts::Options) -> String {