access list: use hex crate for info hash parsing

Cargo.lock

@@ -76,6 +76,7 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "hashbrown 0.11.2",
+ "hex",
  "indexmap",
  "rand",
  "serde",

TODO.md

@@ -6,7 +6,6 @@
   * rename Allow to Require?
   * serde-rename AccessListTypes to lowercase
   * serde-rename list_type to type?
-  * add tests for info hash parsing
   * implement for aquatic_http and aquatic_ws
 
 * Don't unwrap peer_address

aquatic_common/Cargo.toml

@@ -13,6 +13,7 @@ name = "aquatic_common"
 [dependencies]
 anyhow = "1"
 hashbrown = "0.11.2"
+hex = "0.4"
 indexmap = "1"
 rand = { version = "0.8", features = ["small_rng"] }
 serde = { version = "1", features = ["derive"] }

aquatic_common/src/lib.rs

@@ -36,22 +36,9 @@ pub struct AccessList(HashSet<[u8; 20]>);
 
 impl AccessList {
     fn parse_info_hash(line: String) -> anyhow::Result<[u8; 20]> {
-        if line.len() != 20 {
-            return Err(anyhow::anyhow!("Info hash is not 20 bytes long: {}", line));
-        }
-
         let mut bytes = [0u8; 20];
 
-        for (byte, c) in bytes.iter_mut().zip(line.chars()) {
+        hex::decode_to_slice(line, &mut bytes)?;
-            if c as u32 > 255 {
-                return Err(anyhow::anyhow!(
-                    "Info hash character is not ASCII: {:#?}",
-                    c
-                ));
-            }
-
-            *byte = c as u8;
-        }
 
         Ok(bytes)
     }
@@ -170,3 +157,16 @@ pub fn convert_ipv4_mapped_ipv6(ip_address: IpAddr) -> IpAddr {
         ip_address
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_access_list_parse_info_hash(){
+        assert!(AccessList::parse_info_hash("aaaabbbbccccddddeeeeaaaabbbbccccddddeeee".to_owned()).is_ok());
+        assert!(AccessList::parse_info_hash("aaaabbbbccccddddeeeeaaaabbbbccccddddeeeef".to_owned()).is_err());
+        assert!(AccessList::parse_info_hash("aaaabbbbccccddddeeeeaaaabbbbccccddddeee".to_owned()).is_err());
+        assert!(AccessList::parse_info_hash("aaaabbbbccccddddeeeeaaaabbbbccccddddeeeö".to_owned()).is_err());
+    }
+}