crypto: optimize normalizeAlgorithm hot path

Replace O(n) for...in loop with case-insensitive
StringPrototypeToUpperCase comparisons per algorithm
with O(1) SafeMap lookup. The map is pre-built at module
init alongside kSupportedAlgorithms.

Hoist the opts object literal used in normalizeAlgorithm
to module level to avoid allocating identical
{ prefix, context } objects on every call.

Pre-compute ObjectKeys() for simpleAlgorithmDictionaries
entries at module init to avoid allocating a new keys
array on every normalizeAlgorithm call.

Signed-off-by: Filip Skokan <panva.ip@gmail.com>

Author: panva

lib/internal/crypto/util.js

@@ -16,6 +16,7 @@ const {
   ObjectKeys,
   ObjectPrototypeHasOwnProperty,
   PromiseWithResolvers,
+  SafeMap,
   StringPrototypeToUpperCase,
   Symbol,
   TypedArrayPrototypeGetBuffer,
@@ -453,8 +454,11 @@ const experimentalAlgorithms = [
 ];
 
 // Transform the algorithm definitions into the operation-keyed structure
+// Also builds a parallel Map<UPPERCASED_NAME, canonicalName> per operation
+// for O(1) case-insensitive algorithm name lookup in normalizeAlgorithm.
 function createSupportedAlgorithms(algorithmDefs) {
   const result = {};
+  const nameMap = {};
 
   for (const { 0: algorithmName, 1: operations } of ObjectEntries(algorithmDefs)) {
     // Skip algorithms that are conditionally not supported
@@ -465,6 +469,8 @@ function createSupportedAlgorithms(algorithmDefs) {
 
     for (const { 0: operation, 1: dict } of ObjectEntries(operations)) {
       result[operation] ||= {};
+      nameMap[operation] ||= new SafeMap();
+      nameMap[operation].set(StringPrototypeToUpperCase(algorithmName), algorithmName);
 
       // Add experimental warnings for experimental algorithms
       if (ArrayPrototypeIncludes(experimentalAlgorithms, algorithmName)) {
@@ -482,12 +488,14 @@ function createSupportedAlgorithms(algorithmDefs) {
     }
   }
 
-  return result;
+  return { algorithms: result, nameMap };
 }
 
-const kSupportedAlgorithms = createSupportedAlgorithms(kAlgorithmDefinitions);
+const { algorithms: kSupportedAlgorithms, nameMap: kAlgorithmNameMap } =
+  createSupportedAlgorithms(kAlgorithmDefinitions);
 
 const simpleAlgorithmDictionaries = {
+  __proto__: null,
   AesCbcParams: { iv: 'BufferSource' },
   AesCtrParams: { counter: 'BufferSource' },
   AeadParams: { iv: 'BufferSource', additionalData: 'BufferSource' },
@@ -527,6 +535,12 @@ const simpleAlgorithmDictionaries = {
   TurboShakeParams: {},
 };
 
+// Pre-compute ObjectKeys() for each dictionary entry at module init
+// to avoid allocating a new keys array on every normalizeAlgorithm call.
+for (const { 0: name, 1: types } of ObjectEntries(simpleAlgorithmDictionaries)) {
+  simpleAlgorithmDictionaries[name] = { keys: ObjectKeys(types), types };
+}
+
 function validateMaxBufferLength(data, name) {
   if (data.byteLength > kMaxBufferLength) {
     throw lazyDOMException(
@@ -537,6 +551,11 @@ function validateMaxBufferLength(data, name) {
 
 let webidl;
 
+const kNormalizeAlgorithmOpts = {
+  prefix: 'Failed to normalize algorithm',
+  context: 'passed algorithm',
+};
+
 // https://w3c.github.io/webcrypto/#algorithm-normalization-normalize-an-algorithm
 // adapted for Node.js from Deno's implementation
 // https://github.com/denoland/deno/blob/v1.29.1/ext/crypto/00_crypto.js#L195
@@ -549,69 +568,56 @@ function normalizeAlgorithm(algorithm, op) {
   // 1.
   const registeredAlgorithms = kSupportedAlgorithms[op];
   // 2. 3.
-  const initialAlg = webidl.converters.Algorithm(algorithm, {
-    prefix: 'Failed to normalize algorithm',
-    context: 'passed algorithm',
-  });
+  const initialAlg = webidl.converters.Algorithm(algorithm,
+                                                 kNormalizeAlgorithmOpts);
   // 4.
   let algName = initialAlg.name;
 
-  // 5.
-  let desiredType;
-  for (const key in registeredAlgorithms) {
-    if (!ObjectPrototypeHasOwnProperty(registeredAlgorithms, key)) {
-      continue;
-    }
-    if (
-      StringPrototypeToUpperCase(key) === StringPrototypeToUpperCase(algName)
-    ) {
-      algName = key;
-      desiredType = registeredAlgorithms[key];
-    }
-  }
-  if (desiredType === undefined)
+  // 5. Case-insensitive lookup via pre-built Map (O(1) instead of O(n)).
+  const canonicalName = kAlgorithmNameMap[op]?.get(
+    StringPrototypeToUpperCase(algName));
+  if (canonicalName === undefined)
     throw lazyDOMException('Unrecognized algorithm name', 'NotSupportedError');
 
+  algName = canonicalName;
+  const desiredType = registeredAlgorithms[algName];
+
   // Fast path everything below if the registered dictionary is null
   if (desiredType === null)
     return { name: algName };
 
   // 6.
   const normalizedAlgorithm = webidl.converters[desiredType](
     { __proto__: algorithm, name: algName },
-    {
-      prefix: 'Failed to normalize algorithm',
-      context: 'passed algorithm',
-    },
+    kNormalizeAlgorithmOpts,
   );
   // 7.
   normalizedAlgorithm.name = algName;
 
-  // 9.
-  const dict = simpleAlgorithmDictionaries[desiredType];
-  // 10.
-  const dictKeys = dict ? ObjectKeys(dict) : [];
-  for (let i = 0; i < dictKeys.length; i++) {
-    const member = dictKeys[i];
-    if (!ObjectPrototypeHasOwnProperty(dict, member))
-      continue;
-    const idlType = dict[member];
-    const idlValue = normalizedAlgorithm[member];
-    // 3.
-    if (idlType === 'BufferSource' && idlValue) {
-      const isView = ArrayBufferIsView(idlValue);
-      normalizedAlgorithm[member] = TypedArrayPrototypeSlice(
-        new Uint8Array(
-          isView ? getDataViewOrTypedArrayBuffer(idlValue) : idlValue,
-          isView ? getDataViewOrTypedArrayByteOffset(idlValue) : 0,
-          isView ? getDataViewOrTypedArrayByteLength(idlValue) : ArrayBufferPrototypeGetByteLength(idlValue),
-        ),
-      );
-    } else if (idlType === 'HashAlgorithmIdentifier') {
-      normalizedAlgorithm[member] = normalizeAlgorithm(idlValue, 'digest');
-    } else if (idlType === 'AlgorithmIdentifier') {
-      // This extension point is not used by any supported algorithm (yet?)
-      throw lazyDOMException('Not implemented.', 'NotSupportedError');
+  // 9. 10. Pre-computed keys and types from simpleAlgorithmDictionaries.
+  const dictMeta = simpleAlgorithmDictionaries[desiredType];
+  if (dictMeta) {
+    const { keys: dictKeys, types: dictTypes } = dictMeta;
+    for (let i = 0; i < dictKeys.length; i++) {
+      const member = dictKeys[i];
+      const idlType = dictTypes[member];
+      const idlValue = normalizedAlgorithm[member];
+      // 3.
+      if (idlType === 'BufferSource' && idlValue) {
+        const isView = ArrayBufferIsView(idlValue);
+        normalizedAlgorithm[member] = TypedArrayPrototypeSlice(
+          new Uint8Array(
+            isView ? getDataViewOrTypedArrayBuffer(idlValue) : idlValue,
+            isView ? getDataViewOrTypedArrayByteOffset(idlValue) : 0,
+            isView ? getDataViewOrTypedArrayByteLength(idlValue) : ArrayBufferPrototypeGetByteLength(idlValue),
+          ),
+        );
+      } else if (idlType === 'HashAlgorithmIdentifier') {
+        normalizedAlgorithm[member] = normalizeAlgorithm(idlValue, 'digest');
+      } else if (idlType === 'AlgorithmIdentifier') {
+        // This extension point is not used by any supported algorithm (yet?)
+        throw lazyDOMException('Not implemented.', 'NotSupportedError');
+      }
     }
   }