Add AES-CMAC mode. Fix #133

package.json

@@ -1,6 +1,6 @@
 {
   "name": "asmcrypto.js",
-  "version": "0.21.0",
+  "version": "0.22.0",
   "description": "Asm.js implementation of WebCrypto API",
   "homepage": "https://github.com/vibornoff/asmcrypto.js",
   "main": "asmcrypto.js",

src/aes/cmac/cmac.js

@@ -0,0 +1,63 @@
+import { AES_ECB } from '../ecb/ecb';
+import { AES_CBC_Encrypt } from '../cbc/cbc';
+import { bytes_to_hex, hex_to_bytes } from '../../utils';
+
+/**
+ * @param {Uint8Array} data
+ */
+function mul2(data) {
+  const t = data[0] & 0x80;
+  for (var i = 0; i < 15; i++) {
+    data[i] = (data[i] << 1) ^ ((data[i+1] & 0x80) ? 1 : 0);
+  }
+  data[15] = (data[15] << 1) ^ (t ? 0x87 : 0);
+}
+
+export class AES_CMAC {
+  /**
+   * @param {Uint8Array} key
+   */
+  constructor(key) {
+    this.k = new AES_ECB(key).encrypt(new Uint8Array(16)).result;
+    mul2(this.k);
+    this.cbc = new AES_CBC_Encrypt(key, new Uint8Array(16), false);
+
+    this.buffer = new Uint8Array(16);
+    this.bufferLength = 0;
+    this.result = null;
+  }
+
+  /**
+   * @param {Uint8Array} data
+   */
+  process(data) {
+    if (this.bufferLength + data.length > 16) {
+      this.cbc.process(this.buffer.subarray(0, this.bufferLength));
+      const offset = ((this.bufferLength + data.length - 1) & ~15) - this.bufferLength;
+      this.cbc.process(data.subarray(0, offset));
+      this.buffer.set(data.subarray(offset));
+      this.bufferLength = data.length - offset;
+    } else {
+      this.buffer.set(data, this.bufferLength);
+      this.bufferLength += data.length;
+    }
+    return this;
+  }
+
+  finish() {
+    if (this.bufferLength !== 16) {
+      this.buffer[this.bufferLength] = 0x80;
+      for (let i = this.bufferLength + 1; i < 16; i++) {
+        this.buffer[i] = 0;
+      }
+      mul2(this.k);
+    }
+
+    for (let i = 0; i < 16; i++) {
+      this.buffer[i] ^= this.k[i];
+    }
+
+    this.result = this.cbc.process(this.buffer).result;
+    return this;
+  }
+}

src/aes/cmac/exports.js

@@ -0,0 +1,16 @@
+import { AES_CMAC } from './cmac';
+
+/**
+ * @param {Uint8Array} data
+ * @param {Uint8Array} key
+ * @returns {Uint8Array}
+ */
+function AES_CMAC_bytes(data, key) {
+  if (data === undefined) throw new SyntaxError('data required');
+  if (key === undefined) throw new SyntaxError('key required');
+  return new AES_CMAC(key).process(data).finish().result;
+}
+
+AES_CMAC.bytes = AES_CMAC_bytes;
+
+export { AES_CMAC };

src/entry-export_all.js

@@ -4,6 +4,7 @@ export * from './errors';
 export * from './aes/cbc/exports';
 export * from './aes/ccm/exports';
 export * from './aes/cfb/exports';
+export * from './aes/cmac/exports';
 export * from './aes/ctr/exports';
 export * from './aes/ecb/exports';
 export * from './aes/gcm/exports';

test/aes.js

@@ -967,3 +967,42 @@ testIf( asmCrypto.AES_OFB !== undefined, "asmCrypto.AES_OFB", function () {
         );
     }
 });
+
+testIf( asmCrypto.AES_CMAC !== undefined, "asmCrypto.AES_CMAC", function () {
+    // key, data, result
+    var cmac_vectors = [
+        [
+            asmCrypto.hex_to_bytes('2b7e151628aed2a6abf7158809cf4f3c'),
+            asmCrypto.hex_to_bytes(''),
+            asmCrypto.hex_to_bytes('bb1d6929e95937287fa37d129b756746'),
+        ],
+        [
+            asmCrypto.hex_to_bytes('2b7e151628aed2a6abf7158809cf4f3c'),
+            asmCrypto.hex_to_bytes('6bc1bee22e409f96e93d7e117393172a'),
+            asmCrypto.hex_to_bytes('070a16b46b4d4144f79bdd9dd04a287c'),
+        ],
+        [
+            asmCrypto.hex_to_bytes('2b7e151628aed2a6abf7158809cf4f3c'),
+            asmCrypto.hex_to_bytes('6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411'),
+            asmCrypto.hex_to_bytes('dfa66747de9ae63030ca32611497c827'),
+        ],
+        [
+            asmCrypto.hex_to_bytes('2b7e151628aed2a6abf7158809cf4f3c'),
+            asmCrypto.hex_to_bytes('6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411e5fbc1191a0a52eff69f2445df4f9b17ad2b417be66c3710'),
+            asmCrypto.hex_to_bytes('51f0bebf7e3b9d92fc49741779363cfe'),
+        ],
+    ];
+
+    for ( var i = 0; i < cmac_vectors.length; ++i ) {
+        var key = new Uint8Array( cmac_vectors[i][0] ),
+            data = new Uint8Array( cmac_vectors[i][1] ),
+            result = new Uint8Array( cmac_vectors[i][2] );
+
+        equal(
+            asmCrypto.bytes_to_hex( asmCrypto.AES_CMAC.bytes( data, key ) ),
+            asmCrypto.bytes_to_hex(result),
+                "cmac vector " + i
+        );
+
+    }
+});