text: // Copyright (c) 2014-2017, MyMonero.com
  //
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without modification, are
  // permitted provided that the following conditions are met:
  //
  // 1. Redistributions of source code must retain the above copyright notice, this list of
  //    conditions and the following disclaimer.
  //
  // 2. Redistributions in binary form must reproduce the above copyright notice, this list
  //    of conditions and the following disclaimer in the documentation and/or other
  //    materials provided with the distribution.
  //
  // 3. Neither the name of the copyright holder nor the names of its contributors may be
  //    used to endorse or promote products derived from this software without specific
  //    prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
  // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  // THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  // Original Author: Lucas Jones
  // Modified to remove jQuery dep and support modular inclusion of deps by Paul Shapiro (2016)
  // Modified by luigi1111 2017
  
  var cnUtil = (function (initConfig) {
  
      var config = {};// shallow copy of initConfig
  
      for (var key in initConfig) {
          config[key] = initConfig[key];
      }
  
      config.coinUnits = new JSBigInt(10).pow(config.coinUnitPlaces);
  
      var HASH_STATE_BYTES = 200;
      var HASH_SIZE = 32;
      var ADDRESS_CHECKSUM_SIZE = 4;
      var INTEGRATED_ID_SIZE = 8;
      var ENCRYPTED_PAYMENT_ID_TAIL = 141;
      var CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX = config.addressPrefix;
      var CRYPTONOTE_PUBLIC_INTEGRATED_ADDRESS_BASE58_PREFIX = config.integratedAddressPrefix;
      var CRYPTONOTE_PUBLIC_SUBADDRESS_BASE58_PREFIX = config.subAddressPrefix;
      if (config.testnet === true) {
          CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX = config.addressPrefixTestnet;
          CRYPTONOTE_PUBLIC_INTEGRATED_ADDRESS_BASE58_PREFIX = config.integratedAddressPrefixTestnet;
          CRYPTONOTE_PUBLIC_SUBADDRESS_BASE58_PREFIX = config.subAddressPrefixTestnet;
      }
      var UINT64_MAX = new JSBigInt(2).pow(64);
      var CURRENT_TX_VERSION = 1;
      var OLD_TX_VERSION = 1;
      var RCTTypeFull = 1;
      var RCTTypeSimple = 2;
      var TX_EXTRA_NONCE_MAX_COUNT = 255;
      var TX_EXTRA_TAGS = {
          PADDING: '00',
          PUBKEY: '01',
          NONCE: '02',
          MERGE_MINING: '03'
      };
      var TX_EXTRA_NONCE_TAGS = {
          PAYMENT_ID: '00',
          ENCRYPTED_PAYMENT_ID: '01'
      };
      var KEY_SIZE = 32;
      var STRUCT_SIZES = {
          GE_P3: 160,
          GE_P2: 120,
          GE_P1P1: 160,
          GE_CACHED: 160,
          EC_SCALAR: 32,
          EC_POINT: 32,
          KEY_IMAGE: 32,
          GE_DSMP: 160 * 8, // ge_cached * 8
          SIGNATURE: 64 // ec_scalar * 2
      };
  
      //RCT vars
      var H = "8b655970153799af2aeadc9ff1add0ea6c7251d54154cfa92c173a0dd39c1f94"; //base H for amounts
      var l = JSBigInt("7237005577332262213973186563042994240857116359379907606001950938285454250989"); //curve order (not RCT specific)
      var I = "0100000000000000000000000000000000000000000000000000000000000000"; //identity element
      var Z = "0000000000000000000000000000000000000000000000000000000000000000"; //zero scalar
      //H2 object to speed up some operations
      var H2 = ["8b655970153799af2aeadc9ff1add0ea6c7251d54154cfa92c173a0dd39c1f94", "8faa448ae4b3e2bb3d4d130909f55fcd79711c1c83cdbccadd42cbe1515e8712",
          "12a7d62c7791654a57f3e67694ed50b49a7d9e3fc1e4c7a0bde29d187e9cc71d", "789ab9934b49c4f9e6785c6d57a498b3ead443f04f13df110c5427b4f214c739",
          "771e9299d94f02ac72e38e44de568ac1dcb2edc6edb61f83ca418e1077ce3de8", "73b96db43039819bdaf5680e5c32d741488884d18d93866d4074a849182a8a64",
          "8d458e1c2f68ebebccd2fd5d379f5e58f8134df3e0e88cad3d46701063a8d412", "09551edbe494418e81284455d64b35ee8ac093068a5f161fa6637559177ef404",
          "d05a8866f4df8cee1e268b1d23a4c58c92e760309786cdac0feda1d247a9c9a7", "55cdaad518bd871dd1eb7bc7023e1dc0fdf3339864f88fdd2de269fe9ee1832d",
          "e7697e951a98cfd5712b84bbe5f34ed733e9473fcb68eda66e3788df1958c306", "f92a970bae72782989bfc83adfaa92a4f49c7e95918b3bba3cdc7fe88acc8d47",
          "1f66c2d491d75af915c8db6a6d1cb0cd4f7ddcd5e63d3ba9b83c866c39ef3a2b", "3eec9884b43f58e93ef8deea260004efea2a46344fc5965b1a7dd5d18997efa7",
          "b29f8f0ccb96977fe777d489d6be9e7ebc19c409b5103568f277611d7ea84894", "56b1f51265b9559876d58d249d0c146d69a103636699874d3f90473550fe3f2c",
          "1d7a36575e22f5d139ff9cc510fa138505576b63815a94e4b012bfd457caaada", "d0ac507a864ecd0593fa67be7d23134392d00e4007e2534878d9b242e10d7620",
          "f6c6840b9cf145bb2dccf86e940be0fc098e32e31099d56f7fe087bd5deb5094", "28831a3340070eb1db87c12e05980d5f33e9ef90f83a4817c9f4a0a33227e197",
          "87632273d629ccb7e1ed1a768fa2ebd51760f32e1c0b867a5d368d5271055c6e", "5c7b29424347964d04275517c5ae14b6b5ea2798b573fc94e6e44a5321600cfb",
          "e6945042d78bc2c3bd6ec58c511a9fe859c0ad63fde494f5039e0e8232612bd5", "36d56907e2ec745db6e54f0b2e1b2300abcb422e712da588a40d3f1ebbbe02f6",
          "34db6ee4d0608e5f783650495a3b2f5273c5134e5284e4fdf96627bb16e31e6b", "8e7659fb45a3787d674ae86731faa2538ec0fdf442ab26e9c791fada089467e9",
          "3006cf198b24f31bb4c7e6346000abc701e827cfbb5df52dcfa42e9ca9ff0802", "f5fd403cb6e8be21472e377ffd805a8c6083ea4803b8485389cc3ebc215f002a",
          "3731b260eb3f9482e45f1c3f3b9dcf834b75e6eef8c40f461ea27e8b6ed9473d", "9f9dab09c3f5e42855c2de971b659328a2dbc454845f396ffc053f0bb192f8c3",
          "5e055d25f85fdb98f273e4afe08464c003b70f1ef0677bb5e25706400be620a5", "868bcf3679cb6b500b94418c0b8925f9865530303ae4e4b262591865666a4590",
          "b3db6bd3897afbd1df3f9644ab21c8050e1f0038a52f7ca95ac0c3de7558cb7a", "8119b3a059ff2cac483e69bcd41d6d27149447914288bbeaee3413e6dcc6d1eb",
          "10fc58f35fc7fe7ae875524bb5850003005b7f978c0c65e2a965464b6d00819c", "5acd94eb3c578379c1ea58a343ec4fcff962776fe35521e475a0e06d887b2db9",
          "33daf3a214d6e0d42d2300a7b44b39290db8989b427974cd865db011055a2901", "cfc6572f29afd164a494e64e6f1aeb820c3e7da355144e5124a391d06e9f95ea",
          "d5312a4b0ef615a331f6352c2ed21dac9e7c36398b939aec901c257f6cbc9e8e", "551d67fefc7b5b9f9fdbf6af57c96c8a74d7e45a002078a7b5ba45c6fde93e33",
          "d50ac7bd5ca593c656928f38428017fc7ba502854c43d8414950e96ecb405dc3", "0773e18ea1be44fe1a97e239573cfae3e4e95ef9aa9faabeac1274d3ad261604",
          "e9af0e7ca89330d2b8615d1b4137ca617e21297f2f0ded8e31b7d2ead8714660", "7b124583097f1029a0c74191fe7378c9105acc706695ed1493bb76034226a57b",
          "ec40057b995476650b3db98e9db75738a8cd2f94d863b906150c56aac19caa6b", "01d9ff729efd39d83784c0fe59c4ae81a67034cb53c943fb818b9d8ae7fc33e5",
          "00dfb3c696328c76424519a7befe8e0f6c76f947b52767916d24823f735baf2e", "461b799b4d9ceea8d580dcb76d11150d535e1639d16003c3fb7e9d1fd13083a8",
          "ee03039479e5228fdc551cbde7079d3412ea186a517ccc63e46e9fcce4fe3a6c", "a8cfb543524e7f02b9f045acd543c21c373b4c9b98ac20cec417a6ddb5744e94",
          "932b794bf89c6edaf5d0650c7c4bad9242b25626e37ead5aa75ec8c64e09dd4f", "16b10c779ce5cfef59c7710d2e68441ea6facb68e9b5f7d533ae0bb78e28bf57",
          "0f77c76743e7396f9910139f4937d837ae54e21038ac5c0b3fd6ef171a28a7e4", "d7e574b7b952f293e80dde905eb509373f3f6cd109a02208b3c1e924080a20ca",
          "45666f8c381e3da675563ff8ba23f83bfac30c34abdde6e5c0975ef9fd700cb9", "b24612e454607eb1aba447f816d1a4551ef95fa7247fb7c1f503020a7177f0dd",
          "7e208861856da42c8bb46a7567f8121362d9fb2496f131a4aa9017cf366cdfce", "5b646bff6ad1100165037a055601ea02358c0f41050f9dfe3c95dccbd3087be0",
          "746d1dccfed2f0ff1e13c51e2d50d5324375fbd5bf7ca82a8931828d801d43ab", "cb98110d4a6bb97d22feadbc6c0d8930c5f8fc508b2fc5b35328d26b88db19ae",
          "60b626a033b55f27d7676c4095eababc7a2c7ede2624b472e97f64f96b8cfc0e", "e5b52bc927468df71893eb8197ef820cf76cb0aaf6e8e4fe93ad62d803983104",
          "056541ae5da9961be2b0a5e895e5c5ba153cbb62dd561a427bad0ffd41923199", "f8fef05a3fa5c9f3eba41638b247b711a99f960fe73aa2f90136aeb20329b888"];
  
      //begin rct new functions
      //creates a Pedersen commitment from an amount (in scalar form) and a mask
      //C = bG + aH where b = mask, a = amount
      function commit(amount, mask) {
          if (!valid_hex(mask) || mask.length !== 64 || !valid_hex(amount) || amount.length !== 64) {
              throw "invalid amount or mask!";
          }
          var C = this.ge_double_scalarmult_base_vartime(amount, H, mask);
          return C;
      }
  
      function zeroCommit(amount) {
          if (!valid_hex(amount) || amount.length !== 64) {
              throw "invalid amount!";
          }
          var C = this.ge_double_scalarmult_base_vartime(amount, H, I);
          return C;
      }
  
      this.zeroCommit = zeroCommit;
  
      this.decode_rct_ecdh = function (ecdh, key) {
          var first = this.hash_to_scalar(key);
          var second = this.hash_to_scalar(first);
          return {
              mask: this.sc_sub(ecdh.mask, first),
              amount: this.sc_sub(ecdh.amount, second),
          };
      };
  
      this.encode_rct_ecdh = function (ecdh, key) {
          var first = this.hash_to_scalar(key);
          var second = this.hash_to_scalar(first);
          return {
              mask: this.sc_add(ecdh.mask, first),
              amount: this.sc_add(ecdh.amount, second),
          };
      };
  
      //switch byte order for hex string
      function swapEndian(hex) {
          if (hex.length % 2 !== 0) { return "length must be a multiple of 2!"; }
          var data = "";
          for (var i = 1; i <= hex.length / 2; i++) {
              data += hex.substr(0 - 2 * i, 2);
          }
          return data;
      }
  
      //switch byte order charwise
      function swapEndianC(string) {
          var data = "";
          for (var i = 1; i <= string.length; i++) {
              data += string.substr(0 - i, 1);
          }
          return data;
      }
  
      //for most uses you'll also want to swapEndian after conversion
      //mainly to convert integer "scalars" to usable hexadecimal strings
      function d2h(integer) {
          if (typeof integer !== "string" && integer.toString().length > 15) { throw "integer should be entered as a string for precision"; }
          var padding = "";
          for (i = 0; i < 63; i++) {
              padding += "0";
          }
          return (padding + JSBigInt(integer).toString(16).toLowerCase()).slice(-64);
      }
  
      //integer (string) to scalar
      function d2s(integer) {
          return swapEndian(d2h(integer));
      }
  
      this.d2s = d2s;
  
      //scalar to integer (string)
      function s2d(scalar) {
          return JSBigInt.parse(swapEndian(scalar), 16).toString();
      }
  
      //convert integer string to 64bit "binary" little-endian string
      function d2b(integer) {
          if (typeof integer !== "string" && integer.toString().length > 15) { throw "integer should be entered as a string for precision"; }
          var padding = "";
          for (i = 0; i < 63; i++) {
              padding += "0";
          }
          var a = new JSBigInt(integer);
          if (a.toString(2).length > 64) { throw "amount overflows uint64!"; }
          return swapEndianC((padding + a.toString(2)).slice(-64));
      }
  
      //convert integer string to 64bit base 4 little-endian string
      function d2b4(integer) {
          if (typeof integer !== "string" && integer.toString().length > 15) { throw "integer should be entered as a string for precision"; }
          var padding = "";
          for (i = 0; i < 31; i++) {
              padding += "0";
          }
          var a = new JSBigInt(integer);
          if (a.toString(2).length > 64) { throw "amount overflows uint64!"; }
          return swapEndianC((padding + a.toString(4)).slice(-32));
      }
      //end rct new functions
  
      this.valid_hex = function (hex) {
          var exp = new RegExp("[0-9a-fA-F]{" + hex.length + "}");
          return exp.test(hex);
      };
  
      //simple exclusive or function for two hex inputs
      this.hex_xor = function (hex1, hex2) {
          if (!hex1 || !hex2 || hex1.length !== hex2.length || hex1.length % 2 !== 0 || hex2.length % 2 !== 0) { throw "Hex string(s) is/are invalid!"; }
          var bin1 = hextobin(hex1);
          var bin2 = hextobin(hex2);
          var xor = new Uint8Array(bin1.length);
          for (i = 0; i < xor.length; i++) {
              xor[i] = bin1[i] ^ bin2[i];
          }
          return bintohex(xor);
      };
  
      function hextobin(hex) {
          if (hex.length % 2 !== 0) throw "Hex string has invalid length!";
          var res = new Uint8Array(hex.length / 2);
          for (var i = 0; i < hex.length / 2; ++i) {
              res[i] = parseInt(hex.slice(i * 2, i * 2 + 2), 16);
          }
          return res;
      }
  
      function bintohex(bin) {
          var out = [];
          for (var i = 0; i < bin.length; ++i) {
              out.push(("0" + bin[i].toString(16)).slice(-2));
          }
          return out.join("");
      }
      this.bintohex = bintohex;
      this.hextobin = hextobin;
  
      // Generate a 256-bit / 64-char / 32-byte crypto random
      this.rand_32 = function () {
          return mn_random(256);
      };
  
      // Generate a 128-bit / 32-char / 16-byte crypto random
      this.rand_16 = function () {
          return mn_random(128);
      };
  
      // Generate a 64-bit / 16-char / 8-byte crypto random
      this.rand_8 = function () {
          return mn_random(64);
      };
  
      this.encode_varint = function (i) {
          i = new JSBigInt(i);
          var out = '';
          // While i >= b10000000
          while (i.compare(0x80) >= 0) {
              // out.append i & b01111111 | b10000000
              out += ("0" + ((i.lowVal() & 0x7f) | 0x80).toString(16)).slice(-2);
              i = i.divide(new JSBigInt(2).pow(7));
          }
          out += ("0" + i.toJSValue().toString(16)).slice(-2);
          return out;
      };
  
      this.sc_reduce = function (hex) {
          var input = hextobin(hex);
          if (input.length !== 64) {
              throw "Invalid input length";
          }
          var mem = Module._malloc(64);
          Module.HEAPU8.set(input, mem);
          Module.ccall('sc_reduce', 'void', ['number'], [mem]);
          var output = Module.HEAPU8.subarray(mem, mem + 64);
          Module._free(mem);
          return bintohex(output);
      };
  
      this.sc_reduce32 = function (hex) {
          var input = hextobin(hex);
          if (input.length !== 32) {
              throw "Invalid input length";
          }
          var mem = Module._malloc(32);
          Module.HEAPU8.set(input, mem);
          Module.ccall('sc_reduce32', 'void', ['number'], [mem]);
          var output = Module.HEAPU8.subarray(mem, mem + 32);
          Module._free(mem);
          return bintohex(output);
      };
  
      this.cn_fast_hash = function (input, inlen) {
  		/*if (inlen === undefined || !inlen) {
  			inlen = Math.floor(input.length / 2);
  		}*/
          if (input.length % 2 !== 0 || !this.valid_hex(input)) {
              throw "Input invalid";
          }
          //update to use new keccak impl (approx 45x faster)
          //var state = this.keccak(input, inlen, HASH_STATE_BYTES);
          //return state.substr(0, HASH_SIZE * 2);
          return keccak_256(hextobin(input));
      };
  
      //many functions below are commented out now, and duplicated with the faster nacl impl --luigi1111
      // to be removed completely later
  	/*this.sec_key_to_pub = function(sec) {
  		var input = hextobin(sec);
  		if (input.length !== 32) {
  			throw "Invalid input length";
  		}
  		var input_mem = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(input, input_mem);
  		var ge_p3 = Module._malloc(STRUCT_SIZES.GE_P3);
  		var out_mem = Module._malloc(KEY_SIZE);
  		Module.ccall('ge_scalarmult_base', 'void', ['number', 'number'], [ge_p3, input_mem]);
  		Module.ccall('ge_p3_tobytes', 'void', ['number', 'number'], [out_mem, ge_p3]);
  		var output = Module.HEAPU8.subarray(out_mem, out_mem + KEY_SIZE);
  		Module._free(ge_p3);
  		Module._free(input_mem);
  		Module._free(out_mem);
  		return bintohex(output);
  	};*/
  
      this.sec_key_to_pub = function (sec) {
          if (sec.length !== 64) {
              throw "Invalid sec length";
          }
          return bintohex(nacl.ll.ge_scalarmult_base(hextobin(sec)));
      };
  
      //alias
      this.ge_scalarmult_base = function (sec) {
          return this.sec_key_to_pub(sec);
      };
  
      //accepts arbitrary point, rather than G
  	/*this.ge_scalarmult = function(pub, sec) {
  		if (pub.length !== 64 || sec.length !== 64) {
  			throw "Invalid input length";
  		}
  		var pub_b = hextobin(pub);
  		var sec_b = hextobin(sec);
  		var pub_m = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(pub_b, pub_m);
  		var sec_m = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(sec_b, sec_m);
  		var ge_p3_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		var ge_p2_m = Module._malloc(STRUCT_SIZES.GE_P2);
  		if (Module.ccall("ge_frombytes_vartime", "bool", ["number", "number"], [ge_p3_m, pub_m]) !== 0) {
  			throw "ge_frombytes_vartime returned non-zero error code";
  		}
  		Module.ccall("ge_scalarmult", "void", ["number", "number", "number"], [ge_p2_m, sec_m, ge_p3_m]);
  		var derivation_m = Module._malloc(KEY_SIZE);
  		Module.ccall("ge_tobytes", "void", ["number", "number"], [derivation_m, ge_p2_m]);
  		var res = Module.HEAPU8.subarray(derivation_m, derivation_m + KEY_SIZE);
  		Module._free(pub_m);
  		Module._free(sec_m);
  		Module._free(ge_p3_m);
  		Module._free(ge_p2_m);
  		Module._free(derivation_m);
  		return bintohex(res);
  	};*/
      this.ge_scalarmult = function (pub, sec) {
          if (pub.length !== 64 || sec.length !== 64) {
              throw "Invalid input length";
          }
          return bintohex(nacl.ll.ge_scalarmult(hextobin(pub), hextobin(sec)));
      };
  
      this.pubkeys_to_string = function (spend, view) {
          var prefix = this.encode_varint(CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX);
          var data = prefix + spend + view;
          var checksum = this.cn_fast_hash(data);
          return cnBase58.encode(data + checksum.slice(0, ADDRESS_CHECKSUM_SIZE * 2));
      };
  
      this.get_account_integrated_address = function (address, payment_id8) {
          var decoded_address = decode_address(address);
  
          var prefix = this.encode_varint(CRYPTONOTE_PUBLIC_INTEGRATED_ADDRESS_BASE58_PREFIX);
          var data = prefix + decoded_address.spend + decoded_address.view + payment_id8;
  
          var checksum = this.cn_fast_hash(data);
  
          return cnBase58.encode(data + checksum.slice(0, ADDRESS_CHECKSUM_SIZE * 2));
      };
  
  
      this.decrypt_payment_id = function (payment_id8, tx_public_key, acc_prv_view_key) {
          if (payment_id8.length !== 16) throw "Invalid input length2!";
  
          var key_derivation = this.generate_key_derivation(tx_public_key, acc_prv_view_key);
  
          var pid_key = this.cn_fast_hash(key_derivation + ENCRYPTED_PAYMENT_ID_TAIL.toString(16)).slice(0, INTEGRATED_ID_SIZE * 2);
  
          var decrypted_payment_id = this.hex_xor(payment_id8, pid_key);
  
          return decrypted_payment_id;
      }
  
      // Generate keypair from seed
      this.generate_keys_old = function (seed) {
          if (seed.length !== 64) throw "Invalid input length!";
          var sec = this.sc_reduce32(seed);
          var pub = this.sec_key_to_pub(sec);
          return {
              'sec': sec,
              'pub': pub
          };
      };
  
      // Generate keypair from seed 2
      // as in simplewallet
      this.generate_keys = function (seed) {
          if (seed.length !== 64) throw "Invalid input length!";
          var sec = this.sc_reduce32(seed);
          var pub = this.sec_key_to_pub(sec);
          return {
              'sec': sec,
              'pub': pub
          };
      };
  
      this.random_keypair = function () {
          return this.generate_keys(this.rand_32());
      };
  
      // Random 32-byte ec scalar
      this.random_scalar = function () {
          //var rand = this.sc_reduce(mn_random(64 * 8));
          //return rand.slice(0, STRUCT_SIZES.EC_SCALAR * 2);
          return this.sc_reduce32(this.rand_32());
      };
  
  	/* no longer used
  	this.keccak = function(hex, inlen, outlen) {
  		var input = hextobin(hex);
  		if (input.length !== inlen) {
  			throw "Invalid input length";
  		}
  		if (outlen <= 0) {
  			throw "Invalid output length";
  		}
  		var input_mem = Module._malloc(inlen);
  		Module.HEAPU8.set(input, input_mem);
  		var out_mem = Module._malloc(outlen);
  		Module._keccak(input_mem, inlen | 0, out_mem, outlen | 0);
  		var output = Module.HEAPU8.subarray(out_mem, out_mem + outlen);
  		Module._free(input_mem);
  		Module._free(out_mem);
  		return bintohex(output);
  	};*/
  
  
      this.create_address = function (seed) {
          var keys = {};
          var first;
          if (seed.length !== 64) {
              first = this.cn_fast_hash(seed);
          } else {
              first = seed; //only input reduced seeds or this will not give you the result you want
          }
  
          keys.spend = this.generate_keys(first);
          if (seed.length !== 64) {
              var second = this.cn_fast_hash(first);
          } else {
              var second = this.cn_fast_hash(keys.spend.sec);
          }
  
          keys.view = this.generate_keys(second);
          keys.public_addr = this.pubkeys_to_string(keys.spend.pub, keys.view.pub);
          return keys;
      };
  
  
      this.create_addr_prefix = function (seed) {
          var first;
          if (seed.length !== 64) {
              first = this.cn_fast_hash(seed);
          } else {
              first = seed;
          }
          var spend = this.generate_keys(first);
          var prefix = this.encode_varint(CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX);
          return cnBase58.encode(prefix + spend.pub).slice(0, 44);
      };
  
      this.decode_address = function (address) {
          var dec = cnBase58.decode(address);
          // console.log(address);
          // console.log('dec', dec);
          // console.log(dec, CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX, CRYPTONOTE_PUBLIC_INTEGRATED_ADDRESS_BASE58_PREFIX);
          var expectedPrefix = this.encode_varint(CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX);
          var expectedPrefixInt = this.encode_varint(CRYPTONOTE_PUBLIC_INTEGRATED_ADDRESS_BASE58_PREFIX);
          var expectedPrefixSub = this.encode_varint(CRYPTONOTE_PUBLIC_SUBADDRESS_BASE58_PREFIX);
          var prefix = dec.slice(0, expectedPrefix.length);
          // console.log(prefix, expectedPrefixInt, expectedPrefix);
          if (prefix !== expectedPrefix && prefix !== expectedPrefixInt && prefix !== expectedPrefixSub) {
              throw "Invalid address prefix";
          }
          dec = dec.slice(expectedPrefix.length);
          var spend = dec.slice(0, 64);
          var view = dec.slice(64, 128);
          if (prefix === expectedPrefixInt) {
              var intPaymentId = dec.slice(128, 128 + (INTEGRATED_ID_SIZE * 2));
              var checksum = dec.slice(128 + (INTEGRATED_ID_SIZE * 2), 128 + (INTEGRATED_ID_SIZE * 2) + (ADDRESS_CHECKSUM_SIZE * 2));
              var expectedChecksum = this.cn_fast_hash(prefix + spend + view + intPaymentId).slice(0, ADDRESS_CHECKSUM_SIZE * 2);
          } else {
              var checksum = dec.slice(128, 128 + (ADDRESS_CHECKSUM_SIZE * 2));
              var expectedChecksum = this.cn_fast_hash(prefix + spend + view).slice(0, ADDRESS_CHECKSUM_SIZE * 2);
          }
  
  
          // console.log('==============');
          // console.log('prefix', prefix);
          // console.log('expectedPrefixInt', expectedPrefixInt);
  
          // console.log('checksum', dec.slice(128 + (INTEGRATED_ID_SIZE * 2), 128 + (INTEGRATED_ID_SIZE * 2) + (ADDRESS_CHECKSUM_SIZE * 2)));
          // console.log(128 + (INTEGRATED_ID_SIZE * 2));
          // console.log(128 + (INTEGRATED_ID_SIZE * 2) + (ADDRESS_CHECKSUM_SIZE * 2));
  
          // console.log('checksum', checksum);
          // console.log('expectedChecksum', expectedChecksum);
          // console.log('==============');
  
          if (checksum !== expectedChecksum) {
              throw "Invalid checksum";
          }
          if (intPaymentId) {
              return {
                  spend: spend,
                  view: view,
                  intPaymentId: intPaymentId
              };
          } else {
              return {
                  spend: spend,
                  view: view
              };
          }
      };
  
      this.is_subaddress = function (addr) {
          var decoded = cnBase58.decode(addr);
          var subaddressPrefix = this.encode_varint(CRYPTONOTE_PUBLIC_SUBADDRESS_BASE58_PREFIX);
          var prefix = decoded.slice(0, subaddressPrefix.length);
  
          return (prefix === subaddressPrefix);
      };
  
      this.valid_keys = function (view_pub, view_sec, spend_pub, spend_sec) {
          var expected_view_pub = this.sec_key_to_pub(view_sec);
          var expected_spend_pub = this.sec_key_to_pub(spend_sec);
          return (expected_spend_pub === spend_pub) && (expected_view_pub === view_pub);
      };
  
      this.hash_to_scalar = function (buf) {
          var hash = this.cn_fast_hash(buf);
          var scalar = this.sc_reduce32(hash);
          return scalar;
      };
  
  	/*this.generate_key_derivation = function(pub, sec) {
  		if (pub.length !== 64 || sec.length !== 64) {
  			throw "Invalid input length";
  		}
  		var pub_b = hextobin(pub);
  		var sec_b = hextobin(sec);
  		var pub_m = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(pub_b, pub_m);
  		var sec_m = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(sec_b, sec_m);
  		var ge_p3_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		var ge_p2_m = Module._malloc(STRUCT_SIZES.GE_P2);
  		var ge_p1p1_m = Module._malloc(STRUCT_SIZES.GE_P1P1);
  		if (Module.ccall("ge_frombytes_vartime", "bool", ["number", "number"], [ge_p3_m, pub_m]) !== 0) {
  			throw "ge_frombytes_vartime returned non-zero error code";
  		}
  		Module.ccall("ge_scalarmult", "void", ["number", "number", "number"], [ge_p2_m, sec_m, ge_p3_m]);
  		Module.ccall("ge_mul8", "void", ["number", "number"], [ge_p1p1_m, ge_p2_m]);
  		Module.ccall("ge_p1p1_to_p2", "void", ["number", "number"], [ge_p2_m, ge_p1p1_m]);
  		var derivation_m = Module._malloc(KEY_SIZE);
  		Module.ccall("ge_tobytes", "void", ["number", "number"], [derivation_m, ge_p2_m]);
  		var res = Module.HEAPU8.subarray(derivation_m, derivation_m + KEY_SIZE);
  		Module._free(pub_m);
  		Module._free(sec_m);
  		Module._free(ge_p3_m);
  		Module._free(ge_p2_m);
  		Module._free(ge_p1p1_m);
  		Module._free(derivation_m);
  		return bintohex(res);
  	};*/
  
      this.generate_key_derivation = function (pub, sec) {
          if (pub.length !== 64 || sec.length !== 64) {
              throw "Invalid input length";
          }
          var P = this.ge_scalarmult(pub, sec);
          return this.ge_scalarmult(P, d2s(8)); //mul8 to ensure group
      };
  
      this.derivation_to_scalar = function (derivation, output_index) {
          var buf = "";
          if (derivation.length !== (STRUCT_SIZES.EC_POINT * 2)) {
              throw "Invalid derivation length!";
          }
          buf += derivation;
          var enc = encode_varint(output_index);
          if (enc.length > 10 * 2) {
              throw "output_index didn't fit in 64-bit varint";
          }
          buf += enc;
          return this.hash_to_scalar(buf);
      };
  
      this.derive_secret_key = function (derivation, out_index, sec) {
          if (derivation.length !== 64 || sec.length !== 64) {
              throw "Invalid input length!";
          }
          var scalar_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          var scalar_b = hextobin(this.derivation_to_scalar(derivation, out_index));
          Module.HEAPU8.set(scalar_b, scalar_m);
          var base_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hextobin(sec), base_m);
          var derived_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          Module.ccall("sc_add", "void", ["number", "number", "number"], [derived_m, base_m, scalar_m]);
          var res = Module.HEAPU8.subarray(derived_m, derived_m + STRUCT_SIZES.EC_SCALAR);
          Module._free(scalar_m);
          Module._free(base_m);
          Module._free(derived_m);
          return bintohex(res);
      };
  
  	/*this.derive_public_key = function(derivation, out_index, pub) {
  		if (derivation.length !== 64 || pub.length !== 64) {
  			throw "Invalid input length!";
  		}
  		var derivation_m = Module._malloc(KEY_SIZE);
  		var derivation_b = hextobin(derivation);
  		Module.HEAPU8.set(derivation_b, derivation_m);
  		var base_m = Module._malloc(KEY_SIZE);
  		var base_b = hextobin(pub);
  		Module.HEAPU8.set(base_b, base_m);
  		var point1_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		var point2_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		var point3_m = Module._malloc(STRUCT_SIZES.GE_CACHED);
  		var point4_m = Module._malloc(STRUCT_SIZES.GE_P1P1);
  		var point5_m = Module._malloc(STRUCT_SIZES.GE_P2);
  		var derived_key_m = Module._malloc(KEY_SIZE);
  		if (Module.ccall("ge_frombytes_vartime", "bool", ["number", "number"], [point1_m, base_m]) !== 0) {
  			throw "ge_frombytes_vartime returned non-zero error code";
  		}
  		var scalar_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
  		var scalar_b = hextobin(this.derivation_to_scalar(bintohex(Module.HEAPU8.subarray(derivation_m, derivation_m + STRUCT_SIZES.EC_POINT)), out_index));
  		Module.HEAPU8.set(scalar_b, scalar_m);
  		Module.ccall("ge_scalarmult_base", "void", ["number", "number"], [point2_m, scalar_m]);
  		Module.ccall("ge_p3_to_cached", "void", ["number", "number"], [point3_m, point2_m]);
  		Module.ccall("ge_add", "void", ["number", "number", "number"], [point4_m, point1_m, point3_m]);
  		Module.ccall("ge_p1p1_to_p2", "void", ["number", "number"], [point5_m, point4_m]);
  		Module.ccall("ge_tobytes", "void", ["number", "number"], [derived_key_m, point5_m]);
  		var res = Module.HEAPU8.subarray(derived_key_m, derived_key_m + KEY_SIZE);
  		Module._free(derivation_m);
  		Module._free(base_m);
  		Module._free(scalar_m);
  		Module._free(point1_m);
  		Module._free(point2_m);
  		Module._free(point3_m);
  		Module._free(point4_m);
  		Module._free(point5_m);
  		Module._free(derived_key_m);
  		return bintohex(res);
  	};*/
  
      this.derive_public_key = function (derivation, out_index, pub) {
          if (derivation.length !== 64 || pub.length !== 64) {
              throw "Invalid input length!";
          }
          var s = this.derivation_to_scalar(derivation, out_index);
          return bintohex(nacl.ll.ge_add(hextobin(pub), hextobin(this.ge_scalarmult_base(s))));
      };
  
      this.hash_to_ec = function (key) {
          if (key.length !== (KEY_SIZE * 2)) {
              throw "Invalid input length";
          }
          var h_m = Module._malloc(HASH_SIZE);
          var point_m = Module._malloc(STRUCT_SIZES.GE_P2);
          var point2_m = Module._malloc(STRUCT_SIZES.GE_P1P1);
          var res_m = Module._malloc(STRUCT_SIZES.GE_P3);
          var hash = hextobin(this.cn_fast_hash(key, KEY_SIZE));
          Module.HEAPU8.set(hash, h_m);
          Module.ccall("ge_fromfe_frombytes_vartime", "void", ["number", "number"], [point_m, h_m]);
          Module.ccall("ge_mul8", "void", ["number", "number"], [point2_m, point_m]);
          Module.ccall("ge_p1p1_to_p3", "void", ["number", "number"], [res_m, point2_m]);
          var res = Module.HEAPU8.subarray(res_m, res_m + STRUCT_SIZES.GE_P3);
          Module._free(h_m);
          Module._free(point_m);
          Module._free(point2_m);
          Module._free(res_m);
          return bintohex(res);
      };
  
      //returns a 32 byte point via "ge_p3_tobytes" rather than a 160 byte "p3", otherwise same as above;
      this.hash_to_ec_2 = function (key) {
          if (key.length !== (KEY_SIZE * 2)) {
              throw "Invalid input length";
          }
          var h_m = Module._malloc(HASH_SIZE);
          var point_m = Module._malloc(STRUCT_SIZES.GE_P2);
          var point2_m = Module._malloc(STRUCT_SIZES.GE_P1P1);
          var res_m = Module._malloc(STRUCT_SIZES.GE_P3);
          var hash = hextobin(this.cn_fast_hash(key, KEY_SIZE));
          var res2_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hash, h_m);
          Module.ccall("ge_fromfe_frombytes_vartime", "void", ["number", "number"], [point_m, h_m]);
          Module.ccall("ge_mul8", "void", ["number", "number"], [point2_m, point_m]);
          Module.ccall("ge_p1p1_to_p3", "void", ["number", "number"], [res_m, point2_m]);
          Module.ccall("ge_p3_tobytes", "void", ["number", "number"], [res2_m, res_m]);
          var res = Module.HEAPU8.subarray(res2_m, res2_m + KEY_SIZE);
          Module._free(h_m);
          Module._free(point_m);
          Module._free(point2_m);
          Module._free(res_m);
          Module._free(res2_m);
          return bintohex(res);
      };
  
      this.generate_key_image_2 = function (pub, sec) {
          if (!pub || !sec || pub.length !== 64 || sec.length !== 64) {
              throw "Invalid input length";
          }
          var pub_m = Module._malloc(KEY_SIZE);
          var sec_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hextobin(pub), pub_m);
          Module.HEAPU8.set(hextobin(sec), sec_m);
          if (Module.ccall("sc_check", "number", ["number"], [sec_m]) !== 0) {
              throw "sc_check(sec) != 0";
          }
          var point_m = Module._malloc(STRUCT_SIZES.GE_P3);
          var point2_m = Module._malloc(STRUCT_SIZES.GE_P2);
          var point_b = hextobin(this.hash_to_ec(pub));
          Module.HEAPU8.set(point_b, point_m);
          var image_m = Module._malloc(STRUCT_SIZES.KEY_IMAGE);
          Module.ccall("ge_scalarmult", "void", ["number", "number", "number"], [point2_m, sec_m, point_m]);
          Module.ccall("ge_tobytes", "void", ["number", "number"], [image_m, point2_m]);
          var res = Module.HEAPU8.subarray(image_m, image_m + STRUCT_SIZES.KEY_IMAGE);
          Module._free(pub_m);
          Module._free(sec_m);
          Module._free(point_m);
          Module._free(point2_m);
          Module._free(image_m);
          return bintohex(res);
      };
  
      this.generate_key_image = function (tx_pub, view_sec, spend_pub, spend_sec, output_index) {
          if (tx_pub.length !== 64) {
              throw "Invalid tx_pub length";
          }
          if (view_sec.length !== 64) {
              throw "Invalid view_sec length";
          }
          if (spend_pub.length !== 64) {
              throw "Invalid spend_pub length";
          }
          if (spend_sec.length !== 64) {
              throw "Invalid spend_sec length";
          }
          var recv_derivation = this.generate_key_derivation(tx_pub, view_sec);
          var ephemeral_pub = this.derive_public_key(recv_derivation, output_index, spend_pub);
          var ephemeral_sec = this.derive_secret_key(recv_derivation, output_index, spend_sec);
          var k_image = this.generate_key_image_2(ephemeral_pub, ephemeral_sec);
          return {
              ephemeral_pub: ephemeral_pub,
              key_image: k_image
          };
      };
  
      this.generate_key_image_helper_rct = function (keys, tx_pub_key, out_index, enc_mask) {
          var recv_derivation = this.generate_key_derivation(tx_pub_key, keys.view.sec);
          if (!recv_derivation) throw "Failed to generate key image";
  
          var mask;
  
          if (enc_mask === I) {
              // this is for ringct coinbase txs (rct type 0). they are ringct tx that have identity mask
              mask = enc_mask; // enc_mask is idenity mask returned by backend.
          }
          else {
              // for other ringct types or for non-ringct txs to this.
              mask = enc_mask ? sc_sub(enc_mask, hash_to_scalar(derivation_to_scalar(recv_derivation, out_index))) : I; //decode mask, or d2s(1) if no mask
          }
  
          var ephemeral_pub = this.derive_public_key(recv_derivation, out_index, keys.spend.pub);
          if (!ephemeral_pub) throw "Failed to generate key image";
          var ephemeral_sec = this.derive_secret_key(recv_derivation, out_index, keys.spend.sec);
          var image = this.generate_key_image_2(ephemeral_pub, ephemeral_sec);
          return {
              in_ephemeral: {
                  pub: ephemeral_pub,
                  sec: ephemeral_sec,
                  mask: mask
              },
              image: image
          };
      };
  
      //curve and scalar functions; split out to make their host functions cleaner and more readable
      //inverts X coordinate -- this seems correct ^_^ -luigi1111
      this.ge_neg = function (point) {
          if (point.length !== 64) {
              throw "expected 64 char hex string";
          }
          return point.slice(0, 62) + ((parseInt(point.slice(62, 63), 16) + 8) % 16).toString(16) + point.slice(63, 64);
      };
  
      //adds two points together, order does not matter
  	/*this.ge_add2 = function(point1, point2) {
  		var point1_m = Module._malloc(KEY_SIZE);
  		var point2_m = Module._malloc(KEY_SIZE);
  		var point1_m2 = Module._malloc(STRUCT_SIZES.GE_P3);
  		var point2_m2 = Module._malloc(STRUCT_SIZES.GE_P3);
  		Module.HEAPU8.set(hextobin(point1), point1_m);
  		Module.HEAPU8.set(hextobin(point2), point2_m);
  		if (Module.ccall("ge_frombytes_vartime", "bool", ["number", "number"], [point1_m2, point1_m]) !== 0) {
  			throw "ge_frombytes_vartime returned non-zero error code";
  		}
  		if (Module.ccall("ge_frombytes_vartime", "bool", ["number", "number"], [point2_m2, point2_m]) !== 0) {
  			throw "ge_frombytes_vartime returned non-zero error code";
  		}
  		var sum_m = Module._malloc(KEY_SIZE);
  		var p2_m = Module._malloc(STRUCT_SIZES.GE_P2);
  		var p1_m = Module._malloc(STRUCT_SIZES.GE_P1P1);
  		var p3_m = Module._malloc(STRUCT_SIZES.GE_CACHED);
  		Module.ccall("ge_p3_to_cached", "void", ["number", "number"], [p3_m, point2_m2]);
  		Module.ccall("ge_add", "void", ["number", "number", "number"], [p1_m, point1_m2, p3_m]);
  		Module.ccall("ge_p1p1_to_p2", "void", ["number", "number"], [p2_m, p1_m]);
  		Module.ccall("ge_tobytes", "void", ["number", "number"], [sum_m, p2_m]);
  		var res = Module.HEAPU8.subarray(sum_m, sum_m + KEY_SIZE);
  		Module._free(point1_m);
  		Module._free(point1_m2);
  		Module._free(point2_m);
  		Module._free(point2_m2);
  		Module._free(p2_m);
  		Module._free(p1_m);
  		Module._free(sum_m);
  		Module._free(p3_m);
  		return bintohex(res);
  	};*/
  
      this.ge_add = function (p1, p2) {
          if (p1.length !== 64 || p2.length !== 64) {
              throw "Invalid input length!";
          }
          return bintohex(nacl.ll.ge_add(hextobin(p1), hextobin(p2)));
      };
  
      //order matters
      this.ge_sub = function (point1, point2) {
          point2n = ge_neg(point2);
          return ge_add(point1, point2n);
      };
  
      //adds two scalars together
      this.sc_add = function (scalar1, scalar2) {
          if (scalar1.length !== 64 || scalar2.length !== 64) {
              throw "Invalid input length!";
          }
          var scalar1_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          var scalar2_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          Module.HEAPU8.set(hextobin(scalar1), scalar1_m);
          Module.HEAPU8.set(hextobin(scalar2), scalar2_m);
          var derived_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          Module.ccall("sc_add", "void", ["number", "number", "number"], [derived_m, scalar1_m, scalar2_m]);
          var res = Module.HEAPU8.subarray(derived_m, derived_m + STRUCT_SIZES.EC_SCALAR);
          Module._free(scalar1_m);
          Module._free(scalar2_m);
          Module._free(derived_m);
          return bintohex(res);
      };
  
      //subtracts one scalar from another
      this.sc_sub = function (scalar1, scalar2) {
          if (scalar1.length !== 64 || scalar2.length !== 64) {
              throw "Invalid input length!";
          }
          var scalar1_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          var scalar2_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          Module.HEAPU8.set(hextobin(scalar1), scalar1_m);
          Module.HEAPU8.set(hextobin(scalar2), scalar2_m);
          var derived_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          Module.ccall("sc_sub", "void", ["number", "number", "number"], [derived_m, scalar1_m, scalar2_m]);
          var res = Module.HEAPU8.subarray(derived_m, derived_m + STRUCT_SIZES.EC_SCALAR);
          Module._free(scalar1_m);
          Module._free(scalar2_m);
          Module._free(derived_m);
          return bintohex(res);
      };
  
      //fun mul function
      this.sc_mul = function (scalar1, scalar2) {
          if (scalar1.length !== 64 || scalar2.length !== 64) {
              throw "Invalid input length!";
          }
          return d2s(JSBigInt(s2d(scalar1)).multiply(JSBigInt(s2d(scalar2))).remainder(l).toString());
      };
  
      //res = c - (ab) mod l; argument names copied from the signature implementation
      this.sc_mulsub = function (sigc, sec, k) {
          if (k.length !== KEY_SIZE * 2 || sigc.length !== KEY_SIZE * 2 || sec.length !== KEY_SIZE * 2 || !this.valid_hex(k) || !this.valid_hex(sigc) || !this.valid_hex(sec)) {
              throw "bad scalar";
          }
          var sec_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hextobin(sec), sec_m);
          var sigc_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hextobin(sigc), sigc_m);
          var k_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hextobin(k), k_m);
          var res_m = Module._malloc(KEY_SIZE);
  
          Module.ccall("sc_mulsub", "void", ["number", "number", "number", "number"], [res_m, sigc_m, sec_m, k_m]);
          res = Module.HEAPU8.subarray(res_m, res_m + KEY_SIZE);
          Module._free(k_m);
          Module._free(sec_m);
          Module._free(sigc_m);
          Module._free(res_m);
          return bintohex(res);
      };
  
      //res = aB + cG; argument names copied from the signature implementation
  	/*this.ge_double_scalarmult_base_vartime = function(sigc, pub, sigr) {
  		var pub_m = Module._malloc(KEY_SIZE);
  		var pub2_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		Module.HEAPU8.set(hextobin(pub), pub_m);
  		if (Module.ccall("ge_frombytes_vartime", "void", ["number", "number"], [pub2_m, pub_m]) !== 0) {
  			throw "Failed to call ge_frombytes_vartime";
  		}
  		var sigc_m = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(hextobin(sigc), sigc_m);
  		var sigr_m = Module._malloc(KEY_SIZE);
  		Module.HEAPU8.set(hextobin(sigr), sigr_m);
  		if (Module.ccall("sc_check", "number", ["number"], [sigc_m]) !== 0 || Module.ccall("sc_check", "number", ["number"], [sigr_m]) !== 0) {
  			throw "bad scalar(s)";
  		}
  		var tmp_m = Module._malloc(STRUCT_SIZES.GE_P2);
  		var res_m = Module._malloc(KEY_SIZE);
  		Module.ccall("ge_double_scalarmult_base_vartime", "void", ["number", "number", "number", "number"], [tmp_m, sigc_m, pub2_m, sigr_m]);
  		Module.ccall("ge_tobytes", "void", ["number", "number"], [res_m, tmp_m]);
  		var res = Module. HEAPU8.subarray(res_m, res_m + KEY_SIZE);
  		Module._free(pub_m);
  		Module._free(pub2_m);
  		Module._free(sigc_m);
  		Module._free(sigr_m);
  		Module._free(tmp_m);
  		Module._free(res_m);
  		return bintohex(res);
  	};*/
  
      this.ge_double_scalarmult_base_vartime = function (c, P, r) {
          if (c.length !== 64 || P.length !== 64 || r.length !== 64) {
              throw "Invalid input length!";
          }
          return bintohex(nacl.ll.ge_double_scalarmult_base_vartime(hextobin(c), hextobin(P), hextobin(r)));
      };
  
      //res = a * Hp(B) + c*D
      //res = sigr * Hp(pub) + sigc * k_image; argument names also copied from the signature implementation; note precomp AND hash_to_ec are done internally!!
  	/*this.ge_double_scalarmult_postcomp_vartime = function(sigr, pub, sigc, k_image) {
  		var image_m = Module._malloc(STRUCT_SIZES.KEY_IMAGE);
  		Module.HEAPU8.set(hextobin(k_image), image_m);
  		var image_unp_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		var image_pre_m = Module._malloc(STRUCT_SIZES.GE_DSMP);
  		var tmp3_m = Module._malloc(STRUCT_SIZES.GE_P3);
  		var sigr_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
  		var sigc_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
  		var tmp2_m = Module._malloc(STRUCT_SIZES.GE_P2);
  		var res_m = Module._malloc(STRUCT_SIZES.EC_POINT);
  		if (Module.ccall("ge_frombytes_vartime", "void", ["number", "number"], [image_unp_m, image_m]) !== 0) {
  			throw "Failed to call ge_frombytes_vartime";
  		}
  		Module.ccall("ge_dsm_precomp", "void", ["number", "number"], [image_pre_m, image_unp_m]);
  		var ec = this.hash_to_ec(pub);
  		Module.HEAPU8.set(hextobin(ec), tmp3_m);
  		Module.HEAPU8.set(hextobin(sigc), sigc_m);
  		Module.HEAPU8.set(hextobin(sigr), sigr_m);
  		Module.ccall("ge_double_scalarmult_precomp_vartime", "void", ["number", "number", "number", "number", "number"], [tmp2_m, sigr_m, tmp3_m, sigc_m, image_pre_m]);
  		Module.ccall("ge_tobytes", "void", ["number", "number"], [res_m, tmp2_m]);
  		var res = Module. HEAPU8.subarray(res_m, res_m + STRUCT_SIZES.EC_POINT);
  		Module._free(image_m);
  		Module._free(image_unp_m);
  		Module._free(image_pre_m);
  		Module._free(tmp3_m);
  		Module._free(sigr_m);
  		Module._free(sigc_m);
  		Module._free(tmp2_m);
  		Module._free(res_m);
  		return bintohex(res);
  	};*/
  
      this.ge_double_scalarmult_postcomp_vartime = function (r, P, c, I) {
          if (c.length !== 64 || P.length !== 64 || r.length !== 64 || I.length !== 64) {
              throw "Invalid input length!";
          }
          var Pb = this.hash_to_ec_2(P);
          return bintohex(nacl.ll.ge_double_scalarmult_postcomp_vartime(hextobin(r), hextobin(Pb), hextobin(c), hextobin(I)));
      };
  
  
  
      //begin RCT functions
  
      //xv: vector of secret keys, 1 per ring (nrings)
      //pm: matrix of pubkeys, indexed by size first
      //iv: vector of indexes, 1 per ring (nrings), can be a string
      //size: ring size
      //nrings: number of rings
      //extensible borromean signatures
      this.genBorromean = function (xv, pm, iv, size, nrings) {
          if (xv.length !== nrings) {
              throw "wrong xv length " + xv.length;
          }
          if (pm.length !== size) {
              throw "wrong pm size " + pm.length;
          }
          for (var i = 0; i < pm.length; i++) {
              if (pm[i].length !== nrings) {
                  throw "wrong pm[" + i + "] length " + pm[i].length;
              }
          }
          if (iv.length !== nrings) {
              throw "wrong iv length " + iv.length;
          }
          for (var i = 0; i < iv.length; i++) {
              if (iv[i] >= size) {
                  throw "bad indices value at: " + i + ": " + iv[i];
              }
          }
          //signature struct
          var bb = {
              s: [],
              ee: ""
          };
          //signature pubkey matrix
          var L = [];
          //add needed sub vectors (1 per ring size)
          for (var i = 0; i < size; i++) {
              bb.s[i] = [];
              L[i] = [];
          }
          //compute starting at the secret index to the last row
          var index;
          var alpha = [];
          for (var i = 0; i < nrings; i++) {
              index = parseInt(iv[i]);
              alpha[i] = random_scalar();
              L[index][i] = ge_scalarmult_base(alpha[i]);
              for (var j = index + 1; j < size; j++) {
                  bb.s[j][i] = random_scalar();
                  var c = hash_to_scalar(L[j - 1][i]);
                  L[j][i] = ge_double_scalarmult_base_vartime(c, pm[j][i], bb.s[j][i]);
              }
          }
          //hash last row to create ee
          var ltemp = "";
          for (var i = 0; i < nrings; i++) {
              ltemp += L[size - 1][i];
          }
          bb.ee = hash_to_scalar(ltemp);
          //compute the rest from 0 to secret index
          for (var i = 0; i < nrings; i++) {
              var cc = bb.ee
              for (var j = 0; j < iv[i]; j++) {
                  bb.s[j][i] = random_scalar();
                  var LL = ge_double_scalarmult_base_vartime(cc, pm[j][i], bb.s[j][i]);
                  cc = hash_to_scalar(LL);
              }
              bb.s[j][i] = sc_mulsub(xv[i], cc, alpha[i]);
          }
          return bb;
      };
  
      //proveRange
      //proveRange gives C, and mask such that \sumCi = C
      //   c.f. http://eprint.iacr.org/2015/1098 section 5.1
      //   and Ci is a commitment to either 0 or s^i, i=0,...,n
      //   thus this proves that "amount" is in [0, s^n] (we assume s to be 4) (2 for now with v2 txes)
      //   mask is a such that C = aG + bH, and b = amount
      //commitMaskObj = {C: commit, mask: mask}
      this.proveRange = function (commitMaskObj, amount, nrings, enc_seed, exponent) {
          var size = 2;
          var C = I; //identity
          var mask = Z; //zero scalar
          var indices = d2b(amount); //base 2 for now
          var sig = {
              Ci: []
              //exp: exponent //doesn't exist for now
          }
  		/*payload stuff - ignore for now
  		seeds = new Array(3);
  		for (var i = 0; i < seeds.length; i++){
  		  seeds[i] = new Array(1);
  		}
  		genSeeds(seeds, enc_seed);
  		*/
          var ai = [];
          var PM = [];
          for (var i = 0; i < size; i++) {
              PM[i] = [];
          }
          var j;
          //start at index and fill PM left and right -- PM[0] holds Ci
          for (i = 0; i < nrings; i++) {
              ai[i] = random_scalar();
              j = indices[i];
              PM[j][i] = ge_scalarmult_base(ai[i]);
              while (j > 0) {
                  j--;
                  PM[j][i] = ge_add(PM[j + 1][i], H2[i]); //will need to use i*2 for base 4 (or different object)
              }
              j = indices[i];
              while (j < size - 1) {
                  j++;
                  PM[j][i] = ge_sub(PM[j - 1][i], H2[i]); //will need to use i*2 for base 4 (or different object)
              }
              mask = sc_add(mask, ai[i]);
          }
  		/*
  		* some more payload stuff here
  		*/
          //copy commitments to sig and sum them to commitment
          for (i = 0; i < nrings; i++) {
              //if (i < nrings - 1) //for later version
              sig.Ci[i] = PM[0][i];
              C = ge_add(C, PM[0][i]);
          }
  		/* exponent stuff - ignore for now
  		if (exponent){
  		  n = JSBigInt(10);
  		  n = n.pow(exponent).toString();
  		  mask = sc_mul(mask, d2s(n)); //new sum
  		}
  		*/
          sig.bsig = this.genBorromean(ai, PM, indices, size, nrings);
          commitMaskObj.C = C;
          commitMaskObj.mask = mask;
          return sig;
      };
  
  
      function array_hash_to_scalar(array) {
          var buf = ""
          for (var i = 0; i < array.length; i++) {
              if (typeof array[i] !== "string") { throw "unexpected array element"; }
              buf += array[i];
          }
          return hash_to_scalar(buf);
      }
  
      // Gen creates a signature which proves that for some column in the keymatrix "pk"
      //   the signer knows a secret key for each row in that column
      // we presently only support matrices of 2 rows (pubkey, commitment)
      // this is a simplied MLSAG_Gen function to reflect that
      // because we don't want to force same secret column for all inputs
      this.MLSAG_Gen = function (message, pk, xx, kimg, index) {
          var cols = pk.length; //ring size
          if (index >= cols) { throw "index out of range"; }
          var rows = pk[0].length; //number of signature rows (always 2)
          if (rows !== 2) { throw "wrong row count"; }
          for (var i = 0; i < cols; i++) {
              if (pk[i].length !== rows) { throw "pk is not rectangular"; }
          }
          if (xx.length !== rows) { throw "bad xx size"; }
  
          var c_old = "";
          var alpha = [];
  
          var rv = {
              ss: [],
              cc: null
          };
          for (i = 0; i < cols; i++) {
              rv.ss[i] = [];
          }
          var toHash = []; //holds 6 elements: message, pubkey, dsRow L, dsRow R, commitment, ndsRow L
          toHash[0] = message;
  
          //secret index (pubkey section)
          alpha[0] = random_scalar(); //need to save alphas for later
          toHash[1] = pk[index][0]; //secret index pubkey
          toHash[2] = ge_scalarmult_base(alpha[0]); //dsRow L
          toHash[3] = generate_key_image_2(pk[index][0], alpha[0]); //dsRow R (key image check)
          //secret index (commitment section)
          alpha[1] = random_scalar();
          toHash[4] = pk[index][1]; //secret index commitment
          toHash[5] = ge_scalarmult_base(alpha[1]); //ndsRow L
  
          c_old = array_hash_to_scalar(toHash);
  
          i = (index + 1) % cols;
          if (i === 0) {
              rv.cc = c_old;
          }
          while (i != index) {
              rv.ss[i][0] = random_scalar(); //dsRow ss
              rv.ss[i][1] = random_scalar(); //ndsRow ss
  
              //!secret index (pubkey section)
              toHash[1] = pk[i][0];
              toHash[2] = ge_double_scalarmult_base_vartime(c_old, pk[i][0], rv.ss[i][0]);
              toHash[3] = ge_double_scalarmult_postcomp_vartime(rv.ss[i][0], pk[i][0], c_old, kimg);
              //!secret index (commitment section)
              toHash[4] = pk[i][1];
              toHash[5] = ge_double_scalarmult_base_vartime(c_old, pk[i][1], rv.ss[i][1]);
              c_old = array_hash_to_scalar(toHash); //hash to get next column c
              i = (i + 1) % cols;
              if (i === 0) {
                  rv.cc = c_old;
              }
          }
          for (i = 0; i < rows; i++) {
              rv.ss[index][i] = sc_mulsub(c_old, xx[i], alpha[i]);
          }
          return rv;
      };
  
      //prepares for MLSAG_Gen
      this.proveRctMG = function (message, pubs, inSk, kimg, mask, Cout, index) {
          var cols = pubs.length;
          if (cols < 3) { throw "cols must be > 2 (mixin)"; }
          var xx = [];
          var PK = [];
          //fill pubkey matrix (copy destination, subtract commitments)
          for (var i = 0; i < cols; i++) {
              PK[i] = [];
              PK[i][0] = pubs[i].dest;
              PK[i][1] = ge_sub(pubs[i].mask, Cout);
          }
          xx[0] = inSk.x;
          xx[1] = sc_sub(inSk.a, mask);
          return this.MLSAG_Gen(message, PK, xx, kimg, index);
      };
  
      this.get_pre_mlsag_hash = function (rv) {
          var hashes = "";
          hashes += rv.message;
          hashes += this.cn_fast_hash(this.serialize_rct_base(rv));
          var buf = serialize_range_proofs(rv);
          hashes += this.cn_fast_hash(buf);
          return this.cn_fast_hash(hashes);
      }
  
      function serialize_range_proofs(rv) {
          var buf = "";
          for (var i = 0; i < rv.p.rangeSigs.length; i++) {
              for (var j = 0; j < rv.p.rangeSigs[i].bsig.s.length; j++) {
                  for (var l = 0; l < rv.p.rangeSigs[i].bsig.s[j].length; l++) {
                      buf += rv.p.rangeSigs[i].bsig.s[j][l];
                  }
              }
              buf += rv.p.rangeSigs[i].bsig.ee;
              for (j = 0; j < rv.p.rangeSigs[i].Ci.length; j++) {
                  buf += rv.p.rangeSigs[i].Ci[j];
              }
          }
          return buf;
      }
  
      //message is normal prefix hash
      //inSk is vector of x,a
      //kimg is vector of kimg
      //destinations is vector of pubkeys (we skip and proxy outAmounts instead)
      //inAmounts is vector of strings
      //outAmounts is vector of strings
      //mixRing is matrix of pubkey, commit (dest, mask)
      //amountKeys is vector of scalars
      //indices is vector
      //txnFee is string
      this.genRct = function (message, inSk, kimg, /*destinations, */inAmounts, outAmounts, mixRing, amountKeys, indices, txnFee) {
          if (outAmounts.length !== amountKeys.length) { throw "different number of amounts/amount_keys"; }
          for (var i = 0; i < mixRing.length; i++) {
              if (mixRing[i].length <= indices[i]) { throw "bad mixRing/index size"; }
          }
          if (mixRing.length !== inSk.length) { throw "mismatched mixRing/inSk"; }
          if (inAmounts.length !== inSk.length) { throw "mismatched inAmounts/inSk"; }
          if (indices.length !== inSk.length) { throw "mismatched indices/inSk"; }
  
          rv = {
              type: inSk.length === 1 ? RCTTypeFull : RCTTypeSimple,
              message: message,
              outPk: [],
              p: {
                  rangeSigs: [],
                  MGs: []
              },
              ecdhInfo: [],
              txnFee: txnFee.toString(),
              pseudoOuts: []
          };
  
          var sumout = Z;
          var cmObj = {
              C: null,
              mask: null
          };
          var nrings = 64; //for base 2/current
          //compute range proofs, etc
          for (i = 0; i < outAmounts.length; i++) {
              var teststart = new Date().getTime();
              rv.p.rangeSigs[i] = this.proveRange(cmObj, outAmounts[i], nrings, 0, 0);
              var testfinish = new Date().getTime() - teststart;
              console.log("Time take for range proof " + i + ": " + testfinish);
              rv.outPk[i] = cmObj.C;
              sumout = sc_add(sumout, cmObj.mask);
              rv.ecdhInfo[i] = this.encode_rct_ecdh({ mask: cmObj.mask, amount: d2s(outAmounts[i]) }, amountKeys[i]);
          }
  
          //simple
          console.log('-----------rv type', rv.type);
          if (rv.type === 2) {
              var ai = [];
              var sumpouts = Z;
              //create pseudoOuts
              for (i = 0; i < inAmounts.length - 1; i++) {
                  ai[i] = random_scalar();
                  sumpouts = sc_add(sumpouts, ai[i]);
                  rv.pseudoOuts[i] = commit(d2s(inAmounts[i]), ai[i]);
              }
              ai[i] = sc_sub(sumout, sumpouts);
              rv.pseudoOuts[i] = commit(d2s(inAmounts[i]), ai[i]);
              var full_message = this.get_pre_mlsag_hash(rv);
              for (i = 0; i < inAmounts.length; i++) {
                  rv.p.MGs.push(this.proveRctMG(full_message, mixRing[i], inSk[i], kimg[i], ai[i], rv.pseudoOuts[i], indices[i]));
              }
          } else {
              var sumC = I;
              //get sum of output commitments to use in MLSAG
              for (i = 0; i < rv.outPk.length; i++) {
                  sumC = ge_add(sumC, rv.outPk[i]);
              }
              sumC = ge_add(sumC, ge_scalarmult(H, d2s(rv.txnFee)));
              var full_message = this.get_pre_mlsag_hash(rv);
              rv.p.MGs.push(this.proveRctMG(full_message, mixRing[0], inSk[0], kimg[0], sumout, sumC, indices[0]));
          }
          return rv;
      };
  
      //end RCT functions
  
  
      this.add_pub_key_to_extra = function (extra, pubkey) {
          if (pubkey.length !== 64) throw "Invalid pubkey length";
          // Append pubkey tag and pubkey
          extra += TX_EXTRA_TAGS.PUBKEY + pubkey;
          return extra;
      };
  
      this.add_nonce_to_extra = function (extra, nonce) {
          // Append extra nonce
          if ((nonce.length % 2) !== 0) {
              throw "Invalid extra nonce";
          }
          if ((nonce.length / 2) > TX_EXTRA_NONCE_MAX_COUNT) {
              throw "Extra nonce must be at most " + TX_EXTRA_NONCE_MAX_COUNT + " bytes";
          }
          // Add nonce tag
          extra += TX_EXTRA_TAGS.NONCE;
          // Encode length of nonce
          extra += ('0' + (nonce.length / 2).toString(16)).slice(-2);
          // Write nonce
          extra += nonce;
          return extra;
      };
  
      this.get_payment_id_nonce = function (payment_id, pid_encrypt) {
          if (payment_id.length !== 64 && payment_id.length !== 16) {
              throw "Invalid payment id";
          }
          var res = '';
          if (pid_encrypt) {
              res += TX_EXTRA_NONCE_TAGS.ENCRYPTED_PAYMENT_ID;
          } else {
              res += TX_EXTRA_NONCE_TAGS.PAYMENT_ID;
          }
          res += payment_id;
          return res;
      };
  
      this.abs_to_rel_offsets = function (offsets) {
          if (offsets.length === 0) return offsets;
          for (var i = offsets.length - 1; i >= 1; --i) {
              offsets[i] = new JSBigInt(offsets[i]).subtract(offsets[i - 1]).toString();
          }
          return offsets;
      };
  
      this.get_tx_prefix_hash = function (tx) {
          var prefix = this.serialize_tx(tx, true);
          return this.cn_fast_hash(prefix);
      };
  
      this.get_tx_hash = function (tx) {
          if (typeof (tx) === 'string') {
              return this.cn_fast_hash(tx);
          } else {
              return this.cn_fast_hash(this.serialize_tx(tx));
          }
      };
  
      this.serialize_tx = function (tx, headeronly) {
          //tx: {
          //  version: uint64,
          //  unlock_time: uint64,
          //  extra: hex,
          //  vin: [{amount: uint64, k_image: hex, key_offsets: [uint64,..]},...],
          //  vout: [{amount: uint64, target: {key: hex}},...],
          //  signatures: [[s,s,...],...]
          //}
          if (headeronly === undefined) {
              headeronly = false;
          }
          var buf = "";
          buf += this.encode_varint(tx.version);
          buf += this.encode_varint(tx.unlock_time);
          buf += this.encode_varint(tx.vin.length);
          var i, j;
          for (i = 0; i < tx.vin.length; i++) {
              var vin = tx.vin[i];
              switch (vin.type) {
                  case "input_to_key":
                      buf += "02";
                      buf += this.encode_varint(vin.amount);
                      buf += this.encode_varint(vin.key_offsets.length);
                      for (j = 0; j < vin.key_offsets.length; j++) {
                          buf += this.encode_varint(vin.key_offsets[j]);
                      }
                      buf += vin.k_image;
                      break;
                  default:
                      throw "Unhandled vin type: " + vin.type;
              }
          }
          buf += this.encode_varint(tx.vout.length);
          for (i = 0; i < tx.vout.length; i++) {
              var vout = tx.vout[i];
              buf += this.encode_varint(vout.amount);
              switch (vout.target.type) {
                  case "txout_to_key":
                      buf += "02";
                      buf += vout.target.key;
                      break;
                  default:
                      throw "Unhandled txout target type: " + vout.target.type;
              }
          }
          if (!this.valid_hex(tx.extra)) {
              throw "Tx extra has invalid hex";
          }
          buf += this.encode_varint(tx.extra.length / 2);
          buf += tx.extra;
          if (!headeronly) {
              if (tx.vin.length !== tx.signatures.length) {
                  throw "Signatures length != vin length";
              }
              for (i = 0; i < tx.vin.length; i++) {
                  for (j = 0; j < tx.signatures[i].length; j++) {
                      buf += tx.signatures[i][j];
                  }
              }
          }
          return buf;
      };
  
      this.serialize_rct_tx_with_hash = function (tx) {
          var hashes = "";
          var buf = "";
          buf += this.serialize_tx(tx, true);
          hashes += this.cn_fast_hash(buf);
          var buf2 = this.serialize_rct_base(tx.rct_signatures);
          hashes += this.cn_fast_hash(buf2);
          buf += buf2;
          var buf3 = serialize_range_proofs(tx.rct_signatures);
          //add MGs
          for (var i = 0; i < tx.rct_signatures.p.MGs.length; i++) {
              for (var j = 0; j < tx.rct_signatures.p.MGs[i].ss.length; j++) {
                  buf3 += tx.rct_signatures.p.MGs[i].ss[j][0];
                  buf3 += tx.rct_signatures.p.MGs[i].ss[j][1];
              }
              buf3 += tx.rct_signatures.p.MGs[i].cc;
          }
          hashes += this.cn_fast_hash(buf3);
          buf += buf3;
          var hash = this.cn_fast_hash(hashes);
          return {
              raw: buf,
              hash: hash,
              prvkey: tx.prvkey
          };
      };
  
      this.serialize_rct_base = function (rv) {
          var buf = "";
          buf += this.encode_varint(rv.type);
          buf += this.encode_varint(rv.txnFee);
          if (rv.type === 2) {
              for (var i = 0; i < rv.pseudoOuts.length; i++) {
                  buf += rv.pseudoOuts[i];
              }
          }
          if (rv.ecdhInfo.length !== rv.outPk.length) {
              throw "mismatched outPk/ecdhInfo!";
          }
          for (i = 0; i < rv.ecdhInfo.length; i++) {
              buf += rv.ecdhInfo[i].mask;
              buf += rv.ecdhInfo[i].amount;
          }
          for (i = 0; i < rv.outPk.length; i++) {
              buf += rv.outPk[i];
          }
          return buf;
      };
  
      this.generate_ring_signature = function (prefix_hash, k_image, keys, sec, real_index) {
          if (k_image.length !== STRUCT_SIZES.KEY_IMAGE * 2) {
              throw "invalid key image length";
          }
          if (sec.length !== KEY_SIZE * 2) {
              throw "Invalid secret key length";
          }
          if (prefix_hash.length !== HASH_SIZE * 2 || !this.valid_hex(prefix_hash)) {
              throw "Invalid prefix hash";
          }
          if (real_index >= keys.length || real_index < 0) {
              throw "real_index is invalid";
          }
          var _ge_tobytes = Module.cwrap("ge_tobytes", "void", ["number", "number"]);
          var _ge_p3_tobytes = Module.cwrap("ge_p3_tobytes", "void", ["number", "number"]);
          var _ge_scalarmult_base = Module.cwrap("ge_scalarmult_base", "void", ["number", "number"]);
          var _ge_scalarmult = Module.cwrap("ge_scalarmult", "void", ["number", "number", "number"]);
          var _sc_add = Module.cwrap("sc_add", "void", ["number", "number", "number"]);
          var _sc_sub = Module.cwrap("sc_sub", "void", ["number", "number", "number"]);
          var _sc_mulsub = Module.cwrap("sc_mulsub", "void", ["number", "number", "number", "number"]);
          var _sc_0 = Module.cwrap("sc_0", "void", ["number"]);
          var _ge_double_scalarmult_base_vartime = Module.cwrap("ge_double_scalarmult_base_vartime", "void", ["number", "number", "number", "number"]);
          var _ge_double_scalarmult_precomp_vartime = Module.cwrap("ge_double_scalarmult_precomp_vartime", "void", ["number", "number", "number", "number", "number"]);
          var _ge_frombytes_vartime = Module.cwrap("ge_frombytes_vartime", "number", ["number", "number"]);
          var _ge_dsm_precomp = Module.cwrap("ge_dsm_precomp", "void", ["number", "number"]);
  
          var buf_size = STRUCT_SIZES.EC_POINT * 2 * keys.length;
          var buf_m = Module._malloc(buf_size);
          var sig_size = STRUCT_SIZES.SIGNATURE * keys.length;
          var sig_m = Module._malloc(sig_size);
  
          // Struct pointer helper functions
          function buf_a(i) {
              return buf_m + STRUCT_SIZES.EC_POINT * (2 * i);
          }
          function buf_b(i) {
              return buf_m + STRUCT_SIZES.EC_POINT * (2 * i + 1);
          }
          function sig_c(i) {
              return sig_m + STRUCT_SIZES.EC_SCALAR * (2 * i);
          }
          function sig_r(i) {
              return sig_m + STRUCT_SIZES.EC_SCALAR * (2 * i + 1);
          }
          var image_m = Module._malloc(STRUCT_SIZES.KEY_IMAGE);
          Module.HEAPU8.set(hextobin(k_image), image_m);
          var i;
          var image_unp_m = Module._malloc(STRUCT_SIZES.GE_P3);
          var image_pre_m = Module._malloc(STRUCT_SIZES.GE_DSMP);
          var sum_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          var k_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          var h_m = Module._malloc(STRUCT_SIZES.EC_SCALAR);
          var tmp2_m = Module._malloc(STRUCT_SIZES.GE_P2);
          var tmp3_m = Module._malloc(STRUCT_SIZES.GE_P3);
          var pub_m = Module._malloc(KEY_SIZE);
          var sec_m = Module._malloc(KEY_SIZE);
          Module.HEAPU8.set(hextobin(sec), sec_m);
          if (_ge_frombytes_vartime(image_unp_m, image_m) != 0) {
              throw "failed to call ge_frombytes_vartime";
          }
          _ge_dsm_precomp(image_pre_m, image_unp_m);
          _sc_0(sum_m);
          for (i = 0; i < keys.length; i++) {
              if (i === real_index) {
                  // Real key
                  var rand = this.random_scalar();
                  Module.HEAPU8.set(hextobin(rand), k_m);
                  _ge_scalarmult_base(tmp3_m, k_m);
                  _ge_p3_tobytes(buf_a(i), tmp3_m);
                  var ec = this.hash_to_ec(keys[i]);
                  Module.HEAPU8.set(hextobin(ec), tmp3_m);
                  _ge_scalarmult(tmp2_m, k_m, tmp3_m);
                  _ge_tobytes(buf_b(i), tmp2_m);
              } else {
                  Module.HEAPU8.set(hextobin(this.random_scalar()), sig_c(i));
                  Module.HEAPU8.set(hextobin(this.random_scalar()), sig_r(i));
                  Module.HEAPU8.set(hextobin(keys[i]), pub_m);
                  if (Module.ccall("ge_frombytes_vartime", "void", ["number", "number"], [tmp3_m, pub_m]) !== 0) {
                      throw "Failed to call ge_frombytes_vartime";
                  }
                  _ge_double_scalarmult_base_vartime(tmp2_m, sig_c(i), tmp3_m, sig_r(i));
                  _ge_tobytes(buf_a(i), tmp2_m);
                  var ec = this.hash_to_ec(keys[i]);
                  Module.HEAPU8.set(hextobin(ec), tmp3_m);
                  _ge_double_scalarmult_precomp_vartime(tmp2_m, sig_r(i), tmp3_m, sig_c(i), image_pre_m);
                  _ge_tobytes(buf_b(i), tmp2_m);
                  _sc_add(sum_m, sum_m, sig_c(i));
              }
          }
          var buf_bin = Module.HEAPU8.subarray(buf_m, buf_m + buf_size);
          var scalar = this.hash_to_scalar(prefix_hash + bintohex(buf_bin));
          Module.HEAPU8.set(hextobin(scalar), h_m);
          _sc_sub(sig_c(real_index), h_m, sum_m);
          _sc_mulsub(sig_r(real_index), sig_c(real_index), sec_m, k_m);
          var sig_data = bintohex(Module.HEAPU8.subarray(sig_m, sig_m + sig_size));
          var sigs = [];
          for (var k = 0; k < keys.length; k++) {
              sigs.push(sig_data.slice(STRUCT_SIZES.SIGNATURE * 2 * k, STRUCT_SIZES.SIGNATURE * 2 * (k + 1)));
          }
          Module._free(image_m);
          Module._free(image_unp_m);
          Module._free(image_pre_m);
          Module._free(sum_m);
          Module._free(k_m);
          Module._free(h_m);
          Module._free(tmp2_m);
          Module._free(tmp3_m);
          Module._free(buf_m);
          Module._free(sig_m);
          Module._free(pub_m);
          Module._free(sec_m);
          return sigs;
      };
  
      this.construct_tx = function (keys, sources, dsts, fee_amount, payment_id, pid_encrypt, realDestViewKey, unlock_time, rct) {
          //we move payment ID stuff here, because we need txkey to encrypt
          var txkey = this.random_keypair();
          console.log(txkey);
          var extra = '';
          if (payment_id) {
              if (pid_encrypt && payment_id.length !== INTEGRATED_ID_SIZE * 2) {
                  throw "payment ID must be " + INTEGRATED_ID_SIZE + " bytes to be encrypted!";
              }
              console.log("Adding payment id: " + payment_id);
              if (pid_encrypt) { //get the derivation from our passed viewkey, then hash that + tail to get encryption key
                  var pid_key = this.cn_fast_hash(this.generate_key_derivation(realDestViewKey, txkey.sec) + ENCRYPTED_PAYMENT_ID_TAIL.toString(16)).slice(0, INTEGRATED_ID_SIZE * 2);
                  console.log("Txkeys:", txkey, "Payment ID key:", pid_key);
                  payment_id = this.hex_xor(payment_id, pid_key);
              }
              var nonce = this.get_payment_id_nonce(payment_id, pid_encrypt);
              console.log("Extra nonce: " + nonce);
              extra = this.add_nonce_to_extra(extra, nonce);
          }
          var tx = {
              unlock_time: unlock_time,
              version: rct ? CURRENT_TX_VERSION : OLD_TX_VERSION,
              extra: extra,
              prvkey: '',
              vin: [],
              vout: []
          };
          if (rct) {
              tx.rct_signatures = {};
          } else {
              tx.signatures = [];
          }
          tx.prvkey = txkey.sec;
  
          var in_contexts = [];
          var inputs_money = JSBigInt.ZERO;
          var i, j;
  
          console.log('Sources: ');
          //run the for loop twice to sort ins by key image
          //first generate key image and other construction data to sort it all in one go
          for (i = 0; i < sources.length; i++) {
              console.log(i + ': ' + this.formatMoneyFull(sources[i].amount));
              if (sources[i].real_out >= sources[i].outputs.length) {
                  throw "real index >= outputs.length";
              }
              // inputs_money = inputs_money.add(sources[i].amount);
  
              // sets res.mask among other things. mask is identity for non-rct transactions
              // and for coinbase ringct (type = 0) txs.
              var res = this.generate_key_image_helper_rct(keys, sources[i].real_out_tx_key, sources[i].real_out_in_tx, sources[i].mask); //mask will be undefined for non-rct
              // in_contexts.push(res.in_ephemeral);
  
              // now we mark if this is ringct coinbase txs. such transactions
              // will have identity mask. Non-ringct txs will have  sources[i].mask set to null.
              // this only works if beckend will produce masks in get_unspent_outs for
              // coinbaser ringct txs.
              //is_rct_coinbases.push((sources[i].mask ? sources[i].mask === I : 0));
  
              console.log('res.in_ephemeral.pub', res, res.in_ephemeral.pub, sources, i);
              if (res.in_ephemeral.pub !== sources[i].outputs[sources[i].real_out].key) {
                  throw "in_ephemeral.pub != source.real_out.key";
              }
              sources[i].key_image = res.image;
              sources[i].in_ephemeral = res.in_ephemeral;
          }
          //sort ins
          sources.sort(function (a, b) {
              return (
                  JSBigInt.parse(a.key_image, 16).compare(
                      JSBigInt.parse(b.key_image, 16),
                  ) * -1
              );
          });
          //copy the sorted sources data to tx
          for (i = 0; i < sources.length; i++) {
              inputs_money = inputs_money.add(sources[i].amount);
              in_contexts.push(sources[i].in_ephemeral);
              var input_to_key = {};
              input_to_key.type = "input_to_key";
              input_to_key.amount = sources[i].amount;
              input_to_key.k_image = sources[i].key_image;
              input_to_key.key_offsets = [];
              for (j = 0; j < sources[i].outputs.length; ++j) {
                  console.log('add to key offsets', sources[i].outputs[j].index, j, sources[i].outputs);
                  input_to_key.key_offsets.push(sources[i].outputs[j].index);
              }
              console.log('key offsets before abs', input_to_key.key_offsets);
              input_to_key.key_offsets = this.abs_to_rel_offsets(input_to_key.key_offsets);
              console.log('key offsets after abs', input_to_key.key_offsets);
              tx.vin.push(input_to_key);
          }
          var outputs_money = JSBigInt.ZERO;
          var out_index = 0;
          var amountKeys = []; //rct only
          for (i = 0; i < dsts.length; ++i) {
              if (new JSBigInt(dsts[i].amount).compare(0) < 0) {
                  throw "dst.amount < 0"; //amount can be zero if no change
              }
              dsts[i].keys = this.decode_address(dsts[i].address);
  
              // R = rD for subaddresses
              if (this.is_subaddress(dsts[i].address)) {
                  txkey.pub = ge_scalarmult(dsts[i].keys.spend, txkey.sec);
              }
              var out_derivation;
              // send change to ourselves
              if (dsts[i].keys.view === keys.view.pub) {
                  out_derivation = this.generate_key_derivation(txkey.pub, keys.view.sec);
              }
              else {
                  out_derivation = this.generate_key_derivation(dsts[i].keys.view, txkey.sec);
              }
  
              if (rct) {
                  amountKeys.push(this.derivation_to_scalar(out_derivation, out_index));
              }
              var out_ephemeral_pub = this.derive_public_key(out_derivation, out_index, dsts[i].keys.spend);
              var out = {
                  amount: dsts[i].amount.toString()
              };
              // txout_to_key
              out.target = {
                  type: "txout_to_key",
                  key: out_ephemeral_pub
              };
              tx.vout.push(out);
              ++out_index;
              outputs_money = outputs_money.add(dsts[i].amount);
          }
  
          // add pub key to extra after we know whether to use R = rG or R = rD
          tx.extra = this.add_pub_key_to_extra(tx.extra, txkey.pub);
  
          if (outputs_money.add(fee_amount).compare(inputs_money) > 0) {
              throw "outputs money (" + this.formatMoneyFull(outputs_money) + ") + fee (" + this.formatMoneyFull(fee_amount) + ") > inputs money (" + this.formatMoneyFull(inputs_money) + ")";
          }
          if (!rct) {
              for (i = 0; i < sources.length; ++i) {
                  var src_keys = [];
                  for (j = 0; j < sources[i].outputs.length; ++j) {
                      src_keys.push(sources[i].outputs[j].key);
                  }
                  var sigs = this.generate_ring_signature(this.get_tx_prefix_hash(tx), tx.vin[i].k_image, src_keys,
                      in_contexts[i].sec, sources[i].real_out);
                  tx.signatures.push(sigs);
              }
          } else { //rct
              var txnFee = fee_amount;
              var keyimages = [];
              var inSk = [];
              var inAmounts = [];
              var mixRing = [];
              var indices = [];
              for (i = 0; i < tx.vin.length; i++) {
                  keyimages.push(tx.vin[i].k_image);
                  inSk.push({
                      x: in_contexts[i].sec,
                      a: in_contexts[i].mask,
                  });
                  inAmounts.push(tx.vin[i].amount);
                  if (in_contexts[i].mask !== I) {
                      //if input is rct (has a valid mask), 0 out amount
                      tx.vin[i].amount = "0";
                  }
                  mixRing[i] = [];
                  for (j = 0; j < sources[i].outputs.length; j++) {
                      mixRing[i].push({
                          dest: sources[i].outputs[j].key,
                          mask: sources[i].outputs[j].commit,
                      });
                  }
                  indices.push(sources[i].real_out);
              }
              var outAmounts = [];
              for (i = 0; i < tx.vout.length; i++) {
                  outAmounts.push(tx.vout[i].amount);
                  tx.vout[i].amount = "0"; //zero out all rct outputs
              }
              console.log('rc signature----');
              var tx_prefix_hash = this.get_tx_prefix_hash(tx);
              tx.rct_signatures = genRct(tx_prefix_hash, inSk, keyimages, /*destinations, */inAmounts, outAmounts, mixRing, amountKeys, indices, txnFee);
  
          }
          console.log(tx);
          return tx;
      };
      this.create_transaction = function (pub_keys, sec_keys, dsts, outputs, mix_outs, fake_outputs_count, fee_amount, payment_id, pid_encrypt, realDestViewKey, unlock_time, rct) {
          unlock_time = unlock_time || 0;
          mix_outs = mix_outs || [];
          var i, j;
          if (dsts.length === 0) {
              throw 'Destinations empty';
          }
          if (mix_outs.length !== outputs.length && fake_outputs_count !== 0) {
              throw 'Wrong number of mix outs provided (' + outputs.length + ' outputs, ' + mix_outs.length + ' mix outs)';
          }
          for (i = 0; i < mix_outs.length; i++) {
              if ((mix_outs[i].outputs || []).length < fake_outputs_count) {
                  throw 'Not enough outputs to mix with';
              }
          }
          var keys = {
              view: {
                  pub: pub_keys.view,
                  sec: sec_keys.view
              },
              spend: {
                  pub: pub_keys.spend,
                  sec: sec_keys.spend
              }
          };
          if (!this.valid_keys(keys.view.pub, keys.view.sec, keys.spend.pub, keys.spend.sec)) {
              throw "Invalid secret keys!";
          }
          var needed_money = JSBigInt.ZERO;
          for (i = 0; i < dsts.length; ++i) {
              needed_money = needed_money.add(dsts[i].amount);
              if (needed_money.compare(UINT64_MAX) !== -1) {
                  throw "Output overflow!";
              }
          }
          var found_money = JSBigInt.ZERO;
          var sources = [];
          console.log('Selected transfers: ', outputs);
          for (i = 0; i < outputs.length; ++i) {
              found_money = found_money.add(outputs[i].amount);
              if (found_money.compare(UINT64_MAX) !== -1) {
                  throw "Input overflow!";
              }
              var src = {
                  outputs: []
              };
              src.amount = new JSBigInt(outputs[i].amount).toString();
              if (mix_outs.length !== 0) {
                  // Sort fake outputs by global index
                  console.log('mix outs before sort', mix_outs[i].outputs);
                  mix_outs[i].outputs.sort(function (a, b) {
                      return new JSBigInt(a.global_index).compare(b.global_index);
                  });
                  j = 0;
  
                  console.log('mix outs sorted', mix_outs[i].outputs);
  
                  while ((src.outputs.length < fake_outputs_count) && (j < mix_outs[i].outputs.length)) {
                      var out = mix_outs[i].outputs[j];
                      console.log('chekcing mixin', out, outputs[i]);
                      if (out.global_index === outputs[i].global_index) {
                          console.log('got mixin the same as output, skipping');
                          j++;
                          continue;
                      }
                      var oe = {};
                      oe.index = out.global_index.toString();
                      oe.key = out.public_key;
                      if (rct) {
                          if (out.rct) {
                              oe.commit = out.rct.slice(0, 64); //add commitment from rct mix outs
                          } else {
                              if (outputs[i].rct) { throw "mix rct outs missing commit"; }
                              oe.commit = zeroCommit(d2s(src.amount)); //create identity-masked commitment for non-rct mix input
                          }
                      }
                      src.outputs.push(oe);
                      j++;
                  }
              }
              var real_oe = {};
              console.log('OUT FOR REAL:', outputs[i].global_index);
              real_oe.index = new JSBigInt(outputs[i].global_index || 0).toString();
              real_oe.key = outputs[i].public_key;
              if (rct) {
                  if (outputs[i].rct) {
                      real_oe.commit = outputs[i].rct.slice(0, 64); //add commitment for real input
                  } else {
                      console.log('ZERO COMMIT');
                      real_oe.commit = zeroCommit(d2s(src.amount)); //create identity-masked commitment for non-rct input
                  }
              }
              var real_index = src.outputs.length;
              for (j = 0; j < src.outputs.length; j++) {
                  if (new JSBigInt(real_oe.index).compare(src.outputs[j].index) < 0) {
                      real_index = j;
                      break;
                  }
              }
              // Add real_oe to outputs
              console.log('inserting real ouput at index', real_index, real_oe, outputs[i], i);
              src.outputs.splice(real_index, 0, real_oe);
              src.real_out_tx_key = outputs[i].tx_pub_key;
              // Real output entry index
              src.real_out = real_index;
              src.real_out_in_tx = outputs[i].index;
              console.log('check mask', outputs, rct, i);
              if (rct) {
                  if (outputs[i].rct) {
                      src.mask = outputs[i].rct.slice(64, 128); //encrypted or idenity mask for coinbase txs.
                  } else {
                      console.log('NULL MASK');
                      src.mask = null; //will be set by generate_key_image_helper_rct
                  }
              }
              sources.push(src);
          }
          console.log('sources: ', sources);
          var change = {
              amount: JSBigInt.ZERO
          };
          var cmp = needed_money.compare(found_money);
          if (cmp < 0) {
              change.amount = found_money.subtract(needed_money);
              if (change.amount.compare(fee_amount) !== 0) {
                  throw "early fee calculation != later";
              }
          } else if (cmp > 0) {
              throw "Need more money than found! (have: " + cnUtil.formatMoney(found_money) + " need: " + cnUtil.formatMoney(needed_money) + ")";
          }
          return this.construct_tx(keys, sources, dsts, fee_amount, payment_id, pid_encrypt, realDestViewKey, unlock_time, rct);
      };
  
      this.estimateRctSize = function (inputs, mixin, outputs) {
          var size = 0;
          size += outputs * 6306;
          size += ((mixin + 1) * 4 + 32 + 8) * inputs; //key offsets + key image + amount
          size += 64 * (mixin + 1) * inputs + 64 * inputs; //signature + pseudoOuts/cc
          size += 74; //extra + whatever, assume long payment ID
          return size;
      };
  
      function trimRight(str, char) {
          while (str[str.length - 1] == char) str = str.slice(0, -1);
          return str;
      }
  
      function padLeft(str, len, char) {
          while (str.length < len) {
              str = char + str;
          }
          return str;
      }
  
      this.printDsts = function (dsts) {
          for (var i = 0; i < dsts.length; i++) {
              console.log(dsts[i].address + ': ' + this.formatMoneyFull(dsts[i].amount));
          }
      };
  
      this.formatMoneyFull = function (units) {
          units = units.toString();
          var symbol = units[0] === '-' ? '-' : '';
          if (symbol === '-') {
              units = units.slice(1);
          }
          var decimal;
          if (units.length >= config.coinUnitPlaces) {
              decimal = units.substr(units.length - config.coinUnitPlaces, config.coinUnitPlaces);
          } else {
              decimal = padLeft(units, config.coinUnitPlaces, '0');
          }
          return symbol + (units.substr(0, units.length - config.coinUnitPlaces) || '0') + '.' + decimal;
      };
  
      this.formatMoneyFullSymbol = function (units) {
          return this.formatMoneyFull(units) + ' ' + config.coinSymbol;
      };
  
      this.formatMoney = function (units) {
          var f = trimRight(this.formatMoneyFull(units), '0');
          if (f[f.length - 1] === '.') {
              return f.slice(0, f.length - 1);
          }
          return f;
      };
  
      this.formatMoneySymbol = function (units) {
          return this.formatMoney(units) + ' ' + config.coinSymbol;
      };
  
      this.parseMoney = function (str) {
          if (!str) return JSBigInt.ZERO;
          var negative = str[0] === '-';
          if (negative) {
              str = str.slice(1);
          }
          var decimalIndex = str.indexOf('.');
          if (decimalIndex == -1) {
              if (negative) {
                  return JSBigInt.multiply(str, config.coinUnits).negate();
              }
              return JSBigInt.multiply(str, config.coinUnits);
          }
          if (decimalIndex + config.coinUnitPlaces + 1 < str.length) {
              str = str.substr(0, decimalIndex + config.coinUnitPlaces + 1);
          }
          if (negative) {
              return new JSBigInt(str.substr(0, decimalIndex)).exp10(config.coinUnitPlaces)
                  .add(new JSBigInt(str.substr(decimalIndex + 1)).exp10(decimalIndex + config.coinUnitPlaces - str.length + 1)).negate;
          }
          return new JSBigInt(str.substr(0, decimalIndex)).exp10(config.coinUnitPlaces)
              .add(new JSBigInt(str.substr(decimalIndex + 1)).exp10(decimalIndex + config.coinUnitPlaces - str.length + 1));
      };
  
      this.decompose_amount_into_digits = function (amount) {
  		/*if (dust_threshold === undefined) {
  		 dust_threshold = config.dustThreshold;
  		 }*/
          amount = amount.toString();
          var ret = [];
          while (amount.length > 0) {
              //split all the way down since v2 fork
  			/*var remaining = new JSBigInt(amount);
  			 if (remaining.compare(config.dustThreshold) <= 0) {
  			 if (remaining.compare(0) > 0) {
  			 ret.push(remaining);
  			 }
  			 break;
  			 }*/
              //check so we don't create 0s
              if (amount[0] !== "0") {
                  var digit = amount[0];
                  while (digit.length < amount.length) {
                      digit += "0";
                  }
                  ret.push(new JSBigInt(digit));
              }
              amount = amount.slice(1);
          }
          return ret;
      };
  
      this.decompose_tx_destinations = function (dsts, rct) {
          var out = [];
          if (rct) {
              for (var i = 0; i < dsts.length; i++) {
                  out.push({
                      address: dsts[i].address,
                      amount: dsts[i].amount
                  });
              }
          } else {
              for (var i = 0; i < dsts.length; i++) {
                  var digits = this.decompose_amount_into_digits(dsts[i].amount);
                  for (var j = 0; j < digits.length; j++) {
                      if (digits[j].compare(0) > 0) {
                          out.push({
                              address: dsts[i].address,
                              amount: digits[j]
                          });
                      }
                  }
              }
          }
          return out.sort(function (a, b) {
              return a["amount"] - b["amount"];
          });
      };
  
      this.is_tx_unlocked = function (unlock_time, blockchain_height) {
          if (!config.maxBlockNumber) {
              throw "Max block number is not set in config!";
          }
          if (unlock_time < config.maxBlockNumber) {
              // unlock time is block height
              return blockchain_height >= unlock_time;
          } else {
              // unlock time is timestamp
              var current_time = Math.round(new Date().getTime() / 1000);
              return current_time >= unlock_time;
          }
      };
  
      this.tx_locked_reason = function (unlock_time, blockchain_height) {
          if (unlock_time < config.maxBlockNumber) {
              // unlock time is block height
              var numBlocks = unlock_time - blockchain_height;
              if (numBlocks <= 0) {
                  return "Transaction is unlocked";
              }
              var unlock_prediction = moment().add(numBlocks * config.avgBlockTime, 'seconds');
              //return "Will be unlocked in " + numBlocks + " blocks, ~" + unlock_prediction.fromNow(true) + ", " + unlock_prediction.calendar() + "";
              return "Will be unlocked in " + numBlocks + " blocks, ~" + unlock_prediction.fromNow(true);
          } else {
              // unlock time is timestamp
              var current_time = Math.round(new Date().getTime() / 1000);
              var time_difference = unlock_time - current_time;
              if (time_difference <= 0) {
                  return "Transaction is unlocked";
              }
              var unlock_moment = moment(unlock_time * 1000);
              //return "Will be unlocked " + unlock_moment.fromNow() + ", " + unlock_moment.calendar();
              return "Will be unlocked " + unlock_moment.fromNow();
          }
      };
  
      function assert(stmt, val) {
          if (!stmt) {
              throw "assert failed" + (val !== undefined ? ': ' + val : '');
          }
      }
  
      return this;
  })(config);