Implement Hash trait for VerifyingKey

src/verifying.rs

@@ -11,6 +11,7 @@
 
 use core::convert::TryFrom;
 use core::fmt::Debug;
+use core::hash::{Hash, Hasher};
 
 use curve25519_dalek::digest::generic_array::typenum::U64;
 use curve25519_dalek::digest::Digest;
@@ -39,7 +40,7 @@ use crate::signing::*;
 
 /// An ed25519 public key.
 // Invariant: VerifyingKey.1 is always the decompression of VerifyingKey.0
-#[derive(Copy, Clone, Default, Eq, PartialEq)]
+#[derive(Copy, Clone, Default, Eq)]
 pub struct VerifyingKey(pub(crate) CompressedEdwardsY, pub(crate) EdwardsPoint);
 
 impl Debug for VerifyingKey {
@@ -54,6 +55,18 @@ impl AsRef<[u8]> for VerifyingKey {
     }
 }
 
+impl Hash for VerifyingKey {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.as_bytes().hash(state);
+    }
+}
+
+impl PartialEq<VerifyingKey> for VerifyingKey {
+    fn eq(&self, other: &VerifyingKey) -> bool {
+        self.as_bytes() == other.as_bytes()
+    }
+}
+
 impl From<&ExpandedSecretKey> for VerifyingKey {
     /// Derive this public key from its corresponding `ExpandedSecretKey`.
     fn from(expanded_secret_key: &ExpandedSecretKey) -> VerifyingKey {

tests/ed25519.rs

@@ -285,6 +285,7 @@ mod vectors {
 mod integrations {
     use super::*;
     use rand::rngs::OsRng;
+    use std::collections::HashMap;
 
     #[test]
     fn sign_verify() {
@@ -429,6 +430,33 @@ mod integrations {
 
         assert!(result.is_ok());
     }
+
+    #[test]
+    fn public_key_hash_trait_check() {
+        let mut csprng = OsRng {};
+        let secret: SigningKey = SigningKey::generate(&mut csprng);
+        let public_from_secret: VerifyingKey = (&secret).into();
+
+        let mut m = HashMap::new();
+        m.insert(public_from_secret, "Example_Public_Key");
+
+        m.insert(public_from_secret, "Updated Value");
+
+        let (k, v) = m.get_key_value(&public_from_secret).unwrap();
+        assert_eq!(k, &public_from_secret);
+        assert_eq!(v.clone(), "Updated Value");
+        assert_eq!(m.len(), 1usize);
+
+        let second_secret: SigningKey = SigningKey::generate(&mut csprng);
+        let public_from_second_secret: VerifyingKey = (&second_secret).into();
+        assert_ne!(public_from_secret, public_from_second_secret);
+        m.insert(public_from_second_secret, "Second public key");
+
+        let (k, v) = m.get_key_value(&public_from_second_secret).unwrap();
+        assert_eq!(k, &public_from_second_secret);
+        assert_eq!(v.clone(), "Second public key");
+        assert_eq!(m.len(), 2usize);
+    }
 }
 
 #[cfg(all(test, feature = "serde"))]