fix final

toyobayashi · Aug 24, 2023 · ca8e0c5 · ca8e0c5
1 parent 532a966
commit ca8e0c5
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Showing 2 changed files with 37 additions and 25 deletions.
diff --git a/wasm/export.js b/wasm/export.js
@@ -77,24 +77,24 @@ Cipher.prototype.update = function (data) {
 };
 
 Cipher.prototype.final = function () {
-  if (this.remain.length === 0) {
-    return new Uint8Array([
-      159,  59, 117,  4, 146, 111,
-      139, 211, 110, 49,  24, 233,
-        3, 164, 205, 74
-    ]);
-  }
-
-  if (!this.autoPadding && ((this.remain.length % 16) !== 0)) {
-    throw new Error('wrong final block length')
+  var data;
+  if (!this.autoPadding) {
+    if ((this.remain.length % 16) !== 0) {
+      throw new Error('wrong final block length');
+    }
+    if (this.remain.length === 0) {
+      return new Uint8Array(0);
+    }
+    data = this.remain;
+  } else {
+    data = new Uint8Array(16);
+    data.set(this.remain);
+    var pad = 16 - this.remain.length;
+    for (var i = this.remain.length; i < 16; ++i) {
+      data[i] = pad;
+    }
   }
 
-  var data = new Uint8Array(16);
-  data.set(this.remain);
-  var pad = 16 - this.remain.length;
-  for (var i = this.remain.length; i < 16; ++i) {
-    data[i] = pad;
-  }
   var source = Module._malloc(16);
   if (!source) throw new Error('malloc failed');
   Module.HEAPU8.set(data, source);

diff --git a/wasm/test/index.js b/wasm/test/index.js
@@ -29,26 +29,38 @@ function testAutoPadding (input, key) {
   const expected = new Uint8Array(nodeAes.update(input))
   assert.deepStrictEqual(actual, expected);
 
-  assert.throws(() => {
-    aes.final()
-  }, /wrong final block length/)
-
-  assert.throws(() => {
-    nodeAes.final()
-  }, /wrong final block length/)
+  if (input.length % 16 === 0) {
+    const actualFinal = aes.final()
+    const expectedFinal = new Uint8Array(nodeAes.final())
+    assert.deepStrictEqual(actualFinal, expectedFinal)
+  } else {
+    assert.throws(() => {
+      aes.final()
+    })
+
+    assert.throws(() => {
+      nodeAes.final()
+    })
+  }
 
   aes.destroy()
   nodeAes.destroy()
 }
 
 wzwasm.default({}).then(() => {
+  test(new Uint8Array(Array.from({ length: 0 }, (_, k) => k)), key)
   test(new Uint8Array(Array.from({ length: 7 }, (_, k) => k)), key)
   test(new Uint8Array(Array.from({ length: 16 }, (_, k) => k)), key)
   test(new Uint8Array(Array.from({ length: 31 }, (_, k) => k)), key)
   test(new Uint8Array(Array.from({ length: 32 }, (_, k) => k)), key)
-  test(new Uint8Array(Array.from({ length: 126 }, (_, k) => k)), key)
-  test(new Uint8Array(Array.from({ length: 256 }, (_, k) => k)), key)
   test(new Uint8Array(Array.from({ length: 65536 }, (_, k) => k)), key)
+  test(new Uint8Array(Array.from({ length: 999999 }, (_, k) => k)), key)
+  testAutoPadding(new Uint8Array(Array.from({ length: 0 }, (_, k) => k)), key)
   testAutoPadding(new Uint8Array(Array.from({ length: 7 }, (_, k) => k)), key)
+  testAutoPadding(new Uint8Array(Array.from({ length: 16 }, (_, k) => k)), key)
+  testAutoPadding(new Uint8Array(Array.from({ length: 31 }, (_, k) => k)), key)
+  testAutoPadding(new Uint8Array(Array.from({ length: 32 }, (_, k) => k)), key)
+  testAutoPadding(new Uint8Array(Array.from({ length: 65536 }, (_, k) => k)), key)
+  testAutoPadding(new Uint8Array(Array.from({ length: 999999 }, (_, k) => k)), key)
   console.log('all test passed')
 })