Add Zeroize to private key

Cargo.toml

@@ -125,6 +125,7 @@ wasmer = { version = "2.2.1" }
 wasmer-compiler-singlepass = { version = "2.2.1" }
 wasmparser = { version = "0.107.0", default-features = false }
 extend = { version = "1.2.0" }
+zeroize = { version = "1.3.0" }
 
 # Both the release and test profiles use `panic = "unwind"` to allow certain parts of the Radix
 # Engine to be able to catch panics. As an example, the native-vm has a `catch_unwind` to catch

radix-common/Cargo.toml

@@ -31,6 +31,7 @@ ed25519-dalek = { workspace = true, features = ["u64_backend"] }
 secp256k1 = { workspace = true, features = ["recovery"], optional = true }
 blst = { workspace = true, optional = false }
 sha3 = { workspace = true, optional = false }
+zeroize = { workspace = true, optional = false }
 
 [dev-dependencies]
 serde_json = { workspace = true }

radix-common/src/crypto/ed25519/private_key.rs

@@ -1,7 +1,10 @@
 use super::Ed25519Signature;
 use crate::internal_prelude::*;
 use ed25519_dalek::{Keypair, PublicKey, SecretKey, Signer};
+use zeroize::Zeroize;
 
+#[derive(Zeroize)]
+#[zeroize(drop)]
 pub struct Ed25519PrivateKey(SecretKey);
 
 impl Ed25519PrivateKey {