symfony_encodePassword_to_js.js

// need to include https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.9-1/crypto-js.min.js


password = "hello";
alert(encodePassword(password));

// return b64 encoded like symfony encodePassword
function encodePassword(stringInput, iterations = 5000) {
  return btoa(hashPassword(stringInput, iterations));
}

// does the hashing to sha512 with iterations
function hashPassword(stringInput, iterations = 5000){
  
  hashWordArray = CryptoJS.SHA512(stringInput);
  uint8array    = convertWordArrayToUint8Array(hashWordArray);
  binaryString  = convertUint8ArrayToBinaryString(uint8array);

  for (var i=1; i<iterations; i++) {
      wordArrayFromString = CryptoJS.enc.Latin1.parse(binaryString+stringInput);
      hashWordArray = CryptoJS.SHA512(wordArrayFromString);
      uint8array    = convertWordArrayToUint8Array(hashWordArray);
      binaryString  = convertUint8ArrayToBinaryString(uint8array);
  }
 
  return binaryString;
}


// binary transform functions from
// https://gist.github.com/getify/7325764

function convertWordArrayToUint8Array(wordArray) {
	var len = wordArray.words.length,
		u8_array = new Uint8Array(len << 2),
		offset = 0, word, i
	;
	for (i=0; i<len; i++) {
		word = wordArray.words[i];
		u8_array[offset++] = word >> 24;
		u8_array[offset++] = (word >> 16) & 0xff;
		u8_array[offset++] = (word >> 8) & 0xff;
		u8_array[offset++] = word & 0xff;
	}
	return u8_array;
}

function convertUint8ArrayToBinaryString(u8Array) {
	var i, len = u8Array.length, b_str = "";
	for (i=0; i<len; i++) {
		b_str += String.fromCharCode(u8Array[i]);
	}
	return b_str;
}