Support hex encoded secret key for --node-key (#7052)

* Support hex encoded secret key for `--node-key`

Adds support for reading a hex encoded secret key when being passed as
file via `--node-key`.

* Make the key loading uniform

* Switch to `hex::decode`

Author: bkchr

client/cli/src/params/node_key_params.rs

@@ -16,7 +16,7 @@
 // You should have received a copy of the GNU General Public License
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
-use sc_network::config::NodeKeyConfig;
+use sc_network::{config::identity::ed25519, config::NodeKeyConfig};
 use sp_core::H256;
 use std::{path::PathBuf, str::FromStr};
 use structopt::StructOpt;
@@ -83,7 +83,7 @@ pub struct NodeKeyParams {
 	/// as follows:
 	///
 	///   `ed25519`:
-	///   The file must contain an unencoded 32 byte Ed25519 secret key.
+	///   The file must contain an unencoded 32 byte or hex encoded Ed25519 secret key.
 	///
 	/// If the file does not exist, it is created with a newly generated secret key of
 	/// the chosen type.
@@ -100,12 +100,11 @@ impl NodeKeyParams {
 				let secret = if let Some(node_key) = self.node_key.as_ref() {
 					parse_ed25519_secret(node_key)?
 				} else {
-					let path = self
-						.node_key_file
-						.clone()
-						.unwrap_or_else(|| net_config_dir.join(NODE_KEY_ED25519_FILE));
-
-					sc_network::config::Secret::File(path)
+					sc_network::config::Secret::File(
+						self.node_key_file
+							.clone()
+							.unwrap_or_else(|| net_config_dir.join(NODE_KEY_ED25519_FILE))
+					)
 				};
 
 				NodeKeyConfig::Ed25519(secret)
@@ -124,7 +123,7 @@ fn parse_ed25519_secret(hex: &str) -> error::Result<sc_network::config::Ed25519S
 	H256::from_str(&hex)
 		.map_err(invalid_node_key)
 		.and_then(|bytes| {
-			sc_network::config::identity::ed25519::SecretKey::from_bytes(bytes)
+			ed25519::SecretKey::from_bytes(bytes)
 				.map(sc_network::config::Secret::Input)
 				.map_err(invalid_node_key)
 		})
@@ -133,7 +132,8 @@ fn parse_ed25519_secret(hex: &str) -> error::Result<sc_network::config::Ed25519S
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use sc_network::config::identity::ed25519;
+	use sc_network::config::identity::{ed25519, Keypair};
+	use std::fs;
 
 	#[test]
 	fn test_node_key_config_input() {
@@ -164,28 +164,34 @@ mod tests {
 
 	#[test]
 	fn test_node_key_config_file() {
-		fn secret_file(net_config_dir: &PathBuf) -> error::Result<()> {
-			NodeKeyType::variants().iter().try_for_each(|t| {
-				let node_key_type = NodeKeyType::from_str(t).unwrap();
-				let tmp = tempfile::Builder::new().prefix("alice").tempdir()?;
-				let file = tmp.path().join(format!("{}_mysecret", t)).to_path_buf();
-				let params = NodeKeyParams {
-					node_key_type,
-					node_key: None,
-					node_key_file: Some(file.clone()),
-				};
-				params.node_key(net_config_dir).and_then(|c| match c {
-					NodeKeyConfig::Ed25519(sc_network::config::Secret::File(ref f))
-						if node_key_type == NodeKeyType::Ed25519 && f == &file =>
-					{
-						Ok(())
-					}
-					_ => Err(error::Error::Input("Unexpected node key config".into())),
-				})
-			})
+		fn check_key(file: PathBuf, key: &ed25519::SecretKey) {
+			let params = NodeKeyParams {
+				node_key_type: NodeKeyType::Ed25519,
+				node_key: None,
+				node_key_file: Some(file),
+			};
+
+			let node_key = params.node_key(&PathBuf::from("not-used"))
+				.expect("Creates node key config")
+				.into_keypair()
+				.expect("Creates node key pair");
+
+			match node_key {
+				Keypair::Ed25519(ref pair)
+					if pair.secret().as_ref() == key.as_ref() => {}
+				_ => panic!("Invalid key"),
+			}
 		}
 
-		assert!(secret_file(&PathBuf::from_str("x").unwrap()).is_ok());
+		let tmp = tempfile::Builder::new().prefix("alice").tempdir().expect("Creates tempfile");
+		let file = tmp.path().join("mysecret").to_path_buf();
+		let key = ed25519::SecretKey::generate();
+
+		fs::write(&file, hex::encode(key.as_ref())).expect("Writes secret key");
+		check_key(file.clone(), &key);
+
+		fs::write(&file, &key).expect("Writes secret key");
+		check_key(file.clone(), &key);
 	}
 
 	#[test]

client/network/src/config.rs

@@ -625,10 +625,26 @@ impl NodeKeyConfig {
 				Ok(Keypair::Ed25519(k.into())),
 
 			Ed25519(Secret::File(f)) =>
-				get_secret(f,
-					|mut b| ed25519::SecretKey::from_bytes(&mut b),
+				get_secret(
+					f,
+					|mut b| {
+						match String::from_utf8(b.to_vec())
+							.ok()
+							.and_then(|s|{
+								if s.len() == 64 {
+									hex::decode(&s).ok()
+								} else {
+									None
+								}}
+							)
+						{
+							Some(s) => ed25519::SecretKey::from_bytes(s),
+							_ => ed25519::SecretKey::from_bytes(&mut b),
+						}
+					},
 					ed25519::SecretKey::generate,
-					|b| b.as_ref().to_vec())
+					|b| b.as_ref().to_vec()
+				)
 				.map(ed25519::Keypair::from)
 				.map(Keypair::Ed25519),
 		}