Add example how to generate Ed25519 signature in the test case

examples/signature-verifier/Cargo.toml

@@ -12,6 +12,8 @@ concordium-std = {path = "../../concordium-std"}
 
 [dev-dependencies]
 concordium-smart-contract-testing = { path = "../../contract-testing" }
+ed25519-dalek = { version = "2.0", features = ["rand_core"]  }
+rand = "0.8.5"
 
 [features]
 default = ["std", "wee_alloc"]

examples/signature-verifier/tests/tests.rs

@@ -9,9 +9,10 @@ const ALICE_ADDR: Address = Address::Account(ALICE);
 const SIGNER: Signer = Signer::with_one_key();
 
 /// Tests that the signature verifier contract returns true when the signature
-/// is valid.
+/// is valid. The signature is generated outside this test case
+/// (e.g. with https://cyphr.me/ed25519_tool/ed.html).
 #[test]
-fn test_signature_check() {
+fn test_outside_signature_check() {
     let mut chain = Chain::new();
 
     // Create an account.
@@ -48,9 +49,9 @@ fn test_signature_check() {
                 .expect("Parameter has valid size."),
         })
         .expect("Call signature verifier contract with an invalid signature.");
-    // Check that it returns `false`.
+    // Check that the signature does NOT verify.
     let rv: bool = update_invalid.parse_return_value().expect("Deserializing bool");
-    assert_eq!(rv, false);
+    assert!(!rv, "Signature verification should fail.");
 
     // Construct a parameter with a valid signature.
     let parameter_valid = VerificationParameter {
@@ -69,7 +70,85 @@ fn test_signature_check() {
                 .expect("Parameter has valid size."),
         })
         .expect("Call signature verifier contract with a valid signature.");
-    // Check that it returns `true`.
+    // Check that the signature verifies.
+    let rv: bool = update.parse_return_value().expect("Deserializing bool");
+    assert!(rv, "Signature checking failed.");
+}
+
+/// Tests that the signature verifier contract returns true when the signature
+/// is valid. The signature is generated in the test case.
+#[test]
+fn test_inside_signature_check() {
+    let mut chain = Chain::new();
+
+    // Create an account.
+    chain.create_account(Account::new(ALICE, Amount::from_ccd(1000)));
+
+    // Load and deploy the module.
+    let module = module_load_v1("concordium-out/module.wasm.v1").expect("Module exists.");
+    let deployment = chain.module_deploy_v1(SIGNER, ALICE, module).expect("Module deploys.");
+
+    // Initialize the signature verifier contract.
+    let init = chain
+        .contract_init(SIGNER, ALICE, Energy::from(10_000), InitContractPayload {
+            amount:    Amount::zero(),
+            mod_ref:   deployment.module_reference,
+            init_name: OwnedContractName::new_unchecked("init_signature-verifier".to_string()),
+            param:     OwnedParameter::empty(),
+        })
+        .expect("Initialize signature verifier contract");
+
+    use ed25519_dalek::{Signer, SigningKey};
+
+    let rng = &mut rand::thread_rng();
+
+    // Construct message, verifying_key, and signature.
+    let message: &[u8] = b"Concordium";
+    let signing_key = SigningKey::generate(rng);
+    let verifying_key = signing_key.verifying_key();
+    let signature = signing_key.sign(&message);
+
+    // Construct a parameter with an invalid signature.
+    let parameter_invalid = VerificationParameter {
+        public_key: PublicKeyEd25519(verifying_key.to_bytes()),
+        signature:  SignatureEd25519(signature.to_bytes()),
+        message:    b"wrong_message".to_vec(),
+    };
+
+    // Call the contract with the invalid signature.
+    let update_invalid = chain
+        .contract_update(SIGNER, ALICE, ALICE_ADDR, Energy::from(10_000), UpdateContractPayload {
+            amount:       Amount::zero(),
+            address:      init.contract_address,
+            receive_name: OwnedReceiveName::new_unchecked("signature-verifier.verify".to_string()),
+            message:      OwnedParameter::from_serial(&parameter_invalid)
+                .expect("Parameter has valid size."),
+        })
+        .expect("Call signature verifier contract with an invalid signature.");
+
+    // Check that the signature does NOT verify.
+    let rv: bool = update_invalid.parse_return_value().expect("Deserializing bool");
+    assert!(!rv, "Signature verification should fail.");
+
+    // Construct a parameter with a valid signature.
+    let parameter_valid = VerificationParameter {
+        public_key: PublicKeyEd25519(verifying_key.to_bytes()),
+        signature:  SignatureEd25519(signature.to_bytes()),
+        message:    message.to_vec(),
+    };
+
+    // Call the contract with the valid signature.
+    let update = chain
+        .contract_update(SIGNER, ALICE, ALICE_ADDR, Energy::from(10_000), UpdateContractPayload {
+            amount:       Amount::zero(),
+            address:      init.contract_address,
+            receive_name: OwnedReceiveName::new_unchecked("signature-verifier.verify".to_string()),
+            message:      OwnedParameter::from_serial(&parameter_valid)
+                .expect("Parameter has valid size."),
+        })
+        .expect("Call signature verifier contract with a valid signature.");
+
+    // Check that the signature verifies.
     let rv: bool = update.parse_return_value().expect("Deserializing bool");
     assert!(rv, "Signature checking failed.");
 }