Handle verification when multiple algorithms are allowed in the settings

src/decoding.rs

@@ -213,12 +213,10 @@ fn verify_signature<'a>(
         return Err(new_error(ErrorKind::MissingAlgorithm));
     }
 
-    if validation.validate_signature {
-        for alg in &validation.algorithms {
-            if key.family != alg.family() {
-                return Err(new_error(ErrorKind::InvalidAlgorithm));
-            }
-        }
+    if validation.validate_signature
+        && !validation.algorithms.iter().any(|alg| alg.family() == key.family)
+    {
+        return Err(new_error(ErrorKind::InvalidAlgorithm));
     }
 
     let (signature, message) = expect_two!(token.rsplitn(2, '.'));
@@ -229,6 +227,10 @@ fn verify_signature<'a>(
         return Err(new_error(ErrorKind::InvalidAlgorithm));
     }
 
+    if header.alg.family() != key.family {
+        return Err(new_error(ErrorKind::InvalidAlgorithm));
+    }
+
     if validation.validate_signature && !verify(signature, message.as_bytes(), key, header.alg)? {
         return Err(new_error(ErrorKind::InvalidSignature));
     }

tests/hmac.rs

@@ -86,6 +86,16 @@ fn decode_token() {
     claims.unwrap();
 }
 
+#[test]
+#[wasm_bindgen_test]
+fn decode_token_with_multiple_algorithms_allowed() {
+    let token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJiQGIuY29tIiwiY29tcGFueSI6IkFDTUUiLCJleHAiOjI1MzI1MjQ4OTF9.9r56oF7ZliOBlOAyiOFperTGxBtPykRQiWNFxhDCW98";
+    let mut validation = Validation::new(Algorithm::HS256);
+    validation.algorithms.push(Algorithm::RS256);
+    let claims = decode::<Claims>(token, &DecodingKey::from_secret(b"secret"), &validation);
+    claims.unwrap();
+}
+
 #[test]
 #[wasm_bindgen_test]
 #[should_panic(expected = "InvalidToken")]
@@ -126,6 +136,50 @@ fn decode_token_wrong_algorithm() {
     claims.unwrap();
 }
 
+#[test]
+#[wasm_bindgen_test]
+#[should_panic(expected = "MissingAlgorithm")]
+fn decode_missing_algorithm() {
+    let token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJiQGIuY29tIiwiY29tcGFueSI6IkFDTUUifQ.I1BvFoHe94AFf09O6tDbcSB8-jp8w6xZqmyHIwPeSdY";
+    let mut validation = Validation::new(Algorithm::HS256);
+    validation.algorithms = vec![];
+    let claims = decode::<Claims>(token, &DecodingKey::from_secret(b"secret"), &validation);
+    claims.unwrap();
+}
+
+#[test]
+#[wasm_bindgen_test]
+#[should_panic(expected = "InvalidAlgorithm")]
+fn decode_mismatched_key_algorithm() {
+    let token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJiQGIuY29tIiwiY29tcGFueSI6IkFDTUUifQ.I1BvFoHe94AFf09O6tDbcSB8-jp8w6xZqmyHIwPeSdY";
+    let mut validation = Validation::new(Algorithm::HS256);
+    validation.algorithms.push(Algorithm::RS256);
+    let key = &DecodingKey::from_rsa_components("aGk", "aGk").unwrap();
+    let claims = decode::<Claims>(token, &key, &validation);
+    claims.unwrap();
+}
+
+#[test]
+#[wasm_bindgen_test]
+#[should_panic(expected = "InvalidAlgorithm")]
+fn decode_invalid_header_algorithm() {
+    let token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJiQGIuY29tIiwiY29tcGFueSI6IkFDTUUifQ.I1BvFoHe94AFf09O6tDbcSB8-jp8w6xZqmyHIwPeSdY";
+    let validation = Validation::new(Algorithm::RS256);
+    let key = &DecodingKey::from_rsa_components("aGk", "aGk").unwrap();
+    let claims = decode::<Claims>(token, &key, &validation);
+    claims.unwrap();
+}
+
+#[test]
+#[wasm_bindgen_test]
+#[should_panic(expected = "InvalidAlgorithm")]
+fn wrong_decoding_key_family() {
+    let token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJiQGIuY29tIiwiY29tcGFueSI6IkFDTUUifQ.I1BvFoHe94AFf09O6tDbcSB8-jp8w6xZqmyHIwPeSdY";
+    let validation = Validation::new(Algorithm::RS256);
+    let claims = decode::<Claims>(token, &DecodingKey::from_secret(b"secret"), &validation);
+    claims.unwrap();
+}
+
 #[test]
 #[wasm_bindgen_test]
 #[should_panic(expected = "InvalidAlgorithm")]