[webcrypto] Add length parameter to HmacKeyAlgorithm. (chromium)

Matches a planned change to the spec:
https://www.w3.org/Bugs/Public/show_bug.cgi?id=25094

Blink side of this change: https://codereview.chromium.org/204013006/

BUG=245025

Review URL: https://codereview.chromium.org/203303006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@257878 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 34 insertions, 3 deletions

diff --git a/content/child/webcrypto/shared_crypto_unittest.cc b/content/child/webcrypto/shared_crypto_unittest.cc
index 55c3bb7..814a26f 100644
--- a/content/child/webcrypto/shared_crypto_unittest.cc
+++ b/content/child/webcrypto/shared_crypto_unittest.cc
@@ -675,6 +675,9 @@ TEST_F(SharedCryptoTest, HMACSampleSets) {
         blink::WebCryptoKeyUsageSign | blink::WebCryptoKeyUsageVerify);
 
     EXPECT_EQ(test_hash.id(), key.algorithm().hmacParams()->hash().id());
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+    EXPECT_EQ(test_key.size() * 8, key.algorithm().hmacParams()->lengthBits());
+#endif
 
     // Verify exported raw key is identical to the imported data
     blink::WebArrayBuffer raw_key;
@@ -955,6 +958,9 @@ TEST_F(SharedCryptoTest, MAYBE(GenerateKeyHmac)) {
     EXPECT_EQ(blink::WebCryptoAlgorithmIdHmac, key.algorithm().id());
     EXPECT_EQ(blink::WebCryptoAlgorithmIdSha1,
               key.algorithm().hmacParams()->hash().id());
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+    EXPECT_EQ(512u, key.algorithm().hmacParams()->lengthBits());
+#endif
 
     blink::WebArrayBuffer raw_key;
     ASSERT_STATUS_SUCCESS(
@@ -975,6 +981,12 @@ TEST_F(SharedCryptoTest, MAYBE(GenerateKeyHmacNoLength)) {
   ASSERT_STATUS_SUCCESS(GenerateSecretKey(algorithm, true, 0, &key));
   EXPECT_TRUE(key.handle());
   EXPECT_EQ(blink::WebCryptoKeyTypeSecret, key.type());
+  EXPECT_EQ(blink::WebCryptoAlgorithmIdHmac, key.algorithm().id());
+  EXPECT_EQ(blink::WebCryptoAlgorithmIdSha1,
+            key.algorithm().hmacParams()->hash().id());
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+    EXPECT_EQ(512u, key.algorithm().hmacParams()->lengthBits());
+#endif
   blink::WebArrayBuffer raw_key;
   ASSERT_STATUS_SUCCESS(ExportKey(blink::WebCryptoKeyFormatRaw, key, &raw_key));
   EXPECT_EQ(64U, raw_key.byteLength());
@@ -982,8 +994,12 @@ TEST_F(SharedCryptoTest, MAYBE(GenerateKeyHmacNoLength)) {
   // The block size for HMAC SHA-512 is larger.
   algorithm = CreateHmacKeyGenAlgorithm(blink::WebCryptoAlgorithmIdSha512, 0);
   ASSERT_STATUS_SUCCESS(GenerateSecretKey(algorithm, true, 0, &key));
+  EXPECT_EQ(blink::WebCryptoAlgorithmIdHmac, key.algorithm().id());
   EXPECT_EQ(blink::WebCryptoAlgorithmIdSha512,
             key.algorithm().hmacParams()->hash().id());
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+    EXPECT_EQ(1024u, key.algorithm().hmacParams()->lengthBits());
+#endif
   ASSERT_STATUS_SUCCESS(ExportKey(blink::WebCryptoKeyFormatRaw, key, &raw_key));
   EXPECT_EQ(128U, raw_key.byteLength());
 }
@@ -1360,6 +1376,9 @@ TEST_F(SharedCryptoTest, MAYBE(ImportJwkInputConsistency)) {
   EXPECT_EQ(blink::WebCryptoAlgorithmIdHmac, key.algorithm().id());
   EXPECT_EQ(blink::WebCryptoAlgorithmIdSha256,
             key.algorithm().hmacParams()->hash().id());
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+    EXPECT_EQ(320u, key.algorithm().hmacParams()->lengthBits());
+#endif
   EXPECT_EQ(blink::WebCryptoKeyUsageVerify, key.usages());
   key = blink::WebCryptoKey::createNull();
 
@@ -2618,6 +2637,9 @@ TEST_F(SharedCryptoTest, MAYBE(AesKwJwkSymkeyUnwrapKnownData)) {
   EXPECT_EQ(blink::WebCryptoAlgorithmIdHmac, unwrapped_key.algorithm().id());
   EXPECT_EQ(blink::WebCryptoAlgorithmIdSha256,
             unwrapped_key.algorithm().hmacParams()->hash().id());
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+  EXPECT_EQ(256u, unwrapped_key.algorithm().hmacParams()->lengthBits());
+#endif
   EXPECT_EQ(true, unwrapped_key.extractable());
   EXPECT_EQ(blink::WebCryptoKeyUsageVerify, unwrapped_key.usages());
 
diff --git a/content/child/webcrypto/webcrypto_util.cc b/content/child/webcrypto/webcrypto_util.cc
index 5e5fc8e..4574d3c 100644
--- a/content/child/webcrypto/webcrypto_util.cc
+++ b/content/child/webcrypto/webcrypto_util.cc
@@ -377,15 +377,24 @@ unsigned int ShaBlockSizeBytes(blink::WebCryptoAlgorithmId hash_id) {
 }
 
 bool CreateSecretKeyAlgorithm(const blink::WebCryptoAlgorithm& algorithm,
-                              unsigned keylen_bytes,
+                              unsigned int keylen_bytes,
                               blink::WebCryptoKeyAlgorithm* key_algorithm) {
   switch (algorithm.id()) {
     case blink::WebCryptoAlgorithmIdHmac: {
       blink::WebCryptoAlgorithm hash = GetInnerHashAlgorithm(algorithm);
       if (hash.isNull())
         return false;
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+      if (keylen_bytes > UINT_MAX / 8)
+        return false;
+#endif
       *key_algorithm = blink::WebCryptoKeyAlgorithm::adoptParamsAndCreate(
-          algorithm.id(), new blink::WebCryptoHmacKeyAlgorithmParams(hash));
+          algorithm.id(),
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+          new blink::WebCryptoHmacKeyAlgorithmParams(hash, keylen_bytes * 8));
+#else
+          new blink::WebCryptoHmacKeyAlgorithmParams(hash));
+#endif
       return true;
     }
     case blink::WebCryptoAlgorithmIdAesKw:
diff --git a/content/child/webcrypto/webcrypto_util.h b/content/child/webcrypto/webcrypto_util.h
index 98160b5..1ca3a17 100644
--- a/content/child/webcrypto/webcrypto_util.h
+++ b/content/child/webcrypto/webcrypto_util.h
@@ -287,7 +287,7 @@ blink::WebCryptoAlgorithm CreateRsaOaepImportAlgorithm(
 unsigned int ShaBlockSizeBytes(blink::WebCryptoAlgorithmId hash_id);
 
 bool CreateSecretKeyAlgorithm(const blink::WebCryptoAlgorithm& algorithm,
-                              unsigned keylen_bytes,
+                              unsigned int keylen_bytes,
                               blink::WebCryptoKeyAlgorithm* key_algorithm);
 
 }  // namespace webcrypto