diff --git a/src/index.ts b/src/index.ts
index 9e7d8b5..326ff88 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -70,7 +70,11 @@ export class IntegrityMetadata implements IntegrityMetadataLike {
     });
   }
 
-  match({ alg, val }: IntegrityMetadataLike): boolean {
+  match(integrity: IntegrityMetadataLike | string | null | undefined): boolean {
+    const { alg, val } = new IntegrityMetadata(integrity);
+    if (!alg) return false;
+    if (!val) return false;
+    if (!(alg in supportedHashAlgorithms)) return false;
     return alg === this.alg && val === this.val;
   }
 
diff --git a/test/integrity-metadata/match.js b/test/integrity-metadata/match.js
index de6ceb5..e265268 100644
--- a/test/integrity-metadata/match.js
+++ b/test/integrity-metadata/match.js
@@ -44,7 +44,7 @@ test("if the hash values are different, return false", function () {
   );
 });
 
-test.todo("if the hash algorithm is unsupported, return false", function () {
+test("if the hash algorithm is unsupported, return false", function () {
   const integrityMetadata = new IntegrityMetadata(
     "sha1-lDpwLQbzRZmu4fjajvn3KWAx1pk=",
   );
@@ -57,7 +57,7 @@ test.todo("if the hash algorithm is unsupported, return false", function () {
   );
 });
 
-test.todo("if null, return false", function () {
+test("if null, return false", function () {
   const integrityMetadata = new IntegrityMetadata(null);
 
   assert.strictEqual(
@@ -66,13 +66,13 @@ test.todo("if null, return false", function () {
   );
 });
 
-test.todo("if empty, return false", function () {
+test("if empty, return false", function () {
   const integrityMetadata = new IntegrityMetadata("");
 
   assert.strictEqual(integrityMetadata.match(new IntegrityMetadata("")), false);
 });
 
-test.todo("if invalid value, return false", function () {
+test("if invalid value, return false", function () {
   const integrityMetadata = new IntegrityMetadata("md5\0/..invalid-value");
 
   assert.strictEqual(