add from_secret_keys for Secret generation for ledger support (#76)

Author: jowparks

src/participant.rs

@@ -8,6 +8,7 @@ use core::cell::OnceCell;
 use core::cmp;
 use core::hash::Hash;
 use core::hash::Hasher;
+use ed25519_dalek::SecretKey;
 use ed25519_dalek::Signer;
 use ed25519_dalek::SigningKey;
 use ed25519_dalek::Verifier;
@@ -80,6 +81,15 @@ impl Secret {
         }
     }
 
+    #[must_use]
+    pub fn from_secret_keys(secret_key_1: &SecretKey, secret_key_2: &SecretKey) -> Self {
+        Self {
+            signing_key: SigningKey::from_bytes(secret_key_1),
+            decryption_key: StaticSecret::from(*secret_key_2),
+            identity: OnceCell::new(),
+        }
+    }
+
     #[inline]
     #[must_use]
     pub fn signing_key(&self) -> &SigningKey {
@@ -320,8 +330,10 @@ mod tests {
     use super::Identity;
     use super::Secret;
     use ed25519_dalek::Signature;
+    use ed25519_dalek::SigningKey;
     use hex_literal::hex;
     use rand::thread_rng;
+    use x25519_dalek::StaticSecret;
 
     #[test]
     fn secret_to_identity() {
@@ -330,6 +342,16 @@ mod tests {
         id.verify().expect("verification failed");
     }
 
+    #[test]
+    fn from_secret_keys() {
+        let mut rng = thread_rng();
+        let secret_key_1 = SigningKey::generate(&mut rng);
+        let secret_key_2 = StaticSecret::random_from_rng(&mut rng);
+        let id = Secret::from_secret_keys(secret_key_1.as_bytes(), secret_key_2.as_bytes())
+            .to_identity();
+        id.verify().expect("verification failed");
+    }
+
     #[test]
     fn secret_deserialization() {
         let secret = Secret::random(thread_rng());