diff --git a/http-signature-normalization-warp/src/digest/mod.rs b/http-signature-normalization-warp/src/digest/mod.rs
index 0eadf6f..bc8977e 100644
--- a/http-signature-normalization-warp/src/digest/mod.rs
+++ b/http-signature-normalization-warp/src/digest/mod.rs
@@ -87,6 +87,24 @@ fn parse_digest_header() -> impl Filter<Extract = (Vec<DigestPart>,), Error = Re
     header::header::<Digest>("Digest").map(|d: Digest| d.parts)
 }
 
+impl<T> DigestVerify for Vec<T>
+where
+    T: DigestVerify,
+{
+    fn verify(&mut self, parts: &[DigestPart], payload: &[u8]) -> bool {
+        self.iter_mut().any(|d| d.verify(parts, payload))
+    }
+}
+
+impl<T> DigestVerify for &mut [T]
+where
+    T: DigestVerify,
+{
+    fn verify(&mut self, parts: &[DigestPart], payload: &[u8]) -> bool {
+        self.iter_mut().any(|d| d.verify(parts, payload))
+    }
+}
+
 impl FromStr for DigestPart {
     type Err = ParseDigestError;