chore: merge main into reject-duplicate-components

Author: thibmeu

Cargo.lock

@@ -58,6 +58,9 @@ pub enum ImplementationError {
     /// of [registered IANA signature algorithms](https://www.iana.org/assignments/http-message-signature/http-message-signature.xhtml)
     /// implemented here is provided by `Algorithms` struct.
     UnsupportedAlgorithm(Algorithm),
+    /// The `alg` signature parameter is unknown or does not match the algorithm
+    /// of the resolved key (RFC 9421 Section 3.2, step 6).
+    AlgorithmMismatch,
     /// An attempt to resolve key identifier to a valid public key failed.
     /// This prevents message verification.
     NoSuchKey,
@@ -98,6 +101,7 @@ impl core::fmt::Display for ImplementationError {
             ImplementationError::UnsupportedAlgorithm(alg) => {
                 write!(f, "unsupported algorithm: {alg:?}")
             }
+            ImplementationError::AlgorithmMismatch => write!(f, "algorithm mismatch"),
             ImplementationError::NoSuchKey => write!(f, "no such key"),
             ImplementationError::InvalidKeyLength => write!(f, "invalid key length"),
             ImplementationError::InvalidSignatureLength => write!(f, "invalid signature length"),

crates/web-bot-auth/src/lib.rs

@@ -598,6 +598,13 @@ impl MessageVerifier {
                 .and_then(|key| keyring.get_prepared(key)),
         })
         .ok_or(ImplementationError::NoSuchKey)?;
+        let parameters = &self.parsed.base.parameters;
+        if parameters.raw.get("alg").is_some()
+            && parameters.details.algorithm.as_ref() != Some(algorithm)
+            && !matches!(prepared, PreparedKey::Unsupported)
+        {
+            return Err(ImplementationError::AlgorithmMismatch);
+        }
         let generation = UtcDateTime::now();
         let (base_representation, _) = self.parsed.base.into_ascii()?;
         let generation = (UtcDateTime::now() - generation).unsigned_abs();
@@ -772,6 +779,31 @@ mod tests {
         assert!(matches!(err, ImplementationError::ParsingError(_)));
     }
 
+    #[test]
+    fn test_verifying_checks_alg_against_key() {
+        // RFC 9421 Section 3.2, step 6.
+        struct WithAlg(&'static str);
+        impl SignedMessage for WithAlg {
+            fn lookup_component(&self, name: &CoveredComponent) -> Vec<String> {
+                (StandardTestVector {})
+                    .lookup_component(name)
+                    .into_iter()
+                    .map(|value| value.replace(r#";alg="ed25519""#, self.0))
+                    .collect()
+            }
+        }
+        let keyring = keyring_with_test_key();
+        for alg in [r#";alg="rsa-pss-sha512""#, r#";alg="foo""#] {
+            let verifier = MessageVerifier::parse(&WithAlg(alg), |(_, _)| true).unwrap();
+            let err = verifier.verify(&keyring, None).unwrap_err();
+            assert!(matches!(err, ImplementationError::AlgorithmMismatch));
+        }
+        // Without `alg`, the key decides; the altered base then fails verification.
+        let verifier = MessageVerifier::parse(&WithAlg(""), |(_, _)| true).unwrap();
+        let err = verifier.verify(&keyring, None).unwrap_err();
+        assert!(matches!(err, ImplementationError::FailedToVerify(_)));
+    }
+
     #[test]
     fn test_verifying_unsupported_algorithm() {
         let mut keyring = KeyRing::default();

crates/web-bot-auth/src/message_signatures.rs

@@ -28,7 +28,7 @@
   },
   "homepage": "https://github.com/cloudflareresearch/web-bot-auth#readme",
   "devDependencies": {
-    "@types/chrome": "0.3.4",
+    "@types/chrome": "0.3.5",
     "@types/libsodium-wrappers": "0.8.2",
     "crx": "5.0.1",
     "http-server": "14.1.1",

examples/browser-extension/package.json

@@ -11,8 +11,8 @@
 		"cf-typegen": "wrangler types"
 	},
 	"devDependencies": {
-		"@cloudflare/vitest-plugin": "^1.4.0",
-		"@cloudflare/workers-types": "^5.20260916.1",
+		"@cloudflare/vitest-plugin": "^1.4.2",
+		"@cloudflare/workers-types": "^5.20261014.1",
 		"wrangler": "^4.132.0"
 	}
 }