SM4加密(uniapp)

参考博文：添加链接描述
1.需要两个js文件
分别是base64.js和sm4.js
2.文件如下
base64.js文件如下

(function(a){if("object"==typeof exports&&"undefined"!=typeof module)module.exports=a();else if("function"==typeof define&&define.amd)define([],a);else{var b;b="undefined"==typeof window?"undefined"==typeof global?"undefined"==typeof self?this:self:global:window,b.base64js=a()}})(function(){return function(){function b(d,e,g){function a(j,i){if(!e[j]){if(!d[j]){var f="function"==typeof require&&require;if(!i&&f)return f(j,!0);if(h)return h(j,!0);var c=new Error("Cannot find module '"+j+"'");throw c.code="MODULE_NOT_FOUND",c}var k=e[j]={exports:{}};d[j][0].call(k.exports,function(b){var c=d[j][1][b];return a(c||b)},k,k.exports,b,d,e,g)}return e[j].exports}for(var h="function"==typeof require&&require,c=0;c>16,j[k++]=255&b>>8,j[k++]=255&b;return 2===h&&(b=l[a.charCodeAt(c)]<<2|l[a.charCodeAt(c+1)]>>4,j[k++]=255&b),1===h&&(b=l[a.charCodeAt(c)]<<10|l[a.charCodeAt(c+1)]<<4|l[a.charCodeAt(c+2)]>>2,j[k++]=255&b>>8,j[k++]=255&b),j}function g(a){return k[63&a>>18]+k[63&a>>12]+k[63&a>>6]+k[63&a]}function h(a,b,c){for(var d,e=[],f=b;fj?j:g+f));return 1===d?(b=a[c-1],e.push(k[b>>2]+k[63&b<<4]+"==")):2===d&&(b=(a[c-2]<<8)+a[c-1],e.push(k[b>>10]+k[63&b>>4]+k[63&b<<2]+"=")),e.join("")}c.byteLength=function(a){var b=d(a),c=b[0],e=b[1];return 3*(c+e)/4-e},c.toByteArray=f,c.fromByteArray=j;for(var k=[],l=[],m="undefined"==typeof Uint8Array?Array:Uint8Array,n="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",o=0,p=n.length;o

sm4.js 文件如下

import base64js from "./base64.js"
(function (r) { if (typeof exports === "object" && typeof module !== "undefined") { module.exports = r() } else { if (typeof define === "function" && define.amd) { define([], r) } else { var e; if (typeof window !== "undefined") { e = window } else { if (typeof global !== "undefined") { e = global } else { if (typeof self !== "undefined") { e = self } else { e = this } } } e.base64js = r() } } })(function () { var r, e, t; return function r(e, t, n) { function o(i, a) { if (!t[i]) { if (!e[i]) { var u = typeof require == "function" && require; if (!a && u) { return u(i, !0) } if (f) { return f(i, !0) } var d = new Error("Cannot find module '" + i + "'"); throw d.code = "MODULE_NOT_FOUND", d } var c = t[i] = { exports: {} }; e[i][0].call(c.exports, function (r) { var t = e[i][1][r]; return o(t ? t : r) }, c, c.exports, r, e, t, n) } return t[i].exports } var f = typeof require == "function" && require; for (var i = 0; i < n.length; i++) { o(n[i]) } return o }({ "/": [function (r, e, t) { t.byteLength = c; t.toByteArray = v; t.fromByteArray = s; var n = []; var o = []; var f = typeof Uint8Array !== "undefined" ? Uint8Array : Array; var i = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; for (var a = 0, u = i.length; a < u; ++a) { n[a] = i[a]; o[i.charCodeAt(a)] = a } o["-".charCodeAt(0)] = 62; o["_".charCodeAt(0)] = 63; function d(r) { var e = r.length; if (e % 4 > 0) { throw new Error("Invalid string. Length must be a multiple of 4") } return r[e - 2] === "=" ? 2 : r[e - 1] === "=" ? 1 : 0 } function c(r) { return r.length * 3 / 4 - d(r) } function v(r) { var e, t, n, i, a; var u = r.length; i = d(r); a = new f(u * 3 / 4 - i); t = i > 0 ? u - 4 : u; var c = 0; for (e = 0; e < t; e += 4) { n = o[r.charCodeAt(e)] << 18 | o[r.charCodeAt(e + 1)] << 12 | o[r.charCodeAt(e + 2)] << 6 | o[r.charCodeAt(e + 3)]; a[c++] = n >> 16 & 255; a[c++] = n >> 8 & 255; a[c++] = n & 255 } if (i === 2) { n = o[r.charCodeAt(e)] << 2 | o[r.charCodeAt(e + 1)] >> 4; a[c++] = n & 255 } else { if (i === 1) { n = o[r.charCodeAt(e)] << 10 | o[r.charCodeAt(e + 1)] << 4 | o[r.charCodeAt(e + 2)] >> 2; a[c++] = n >> 8 & 255; a[c++] = n & 255 } } return a } function l(r) { return n[r >> 18 & 63] + n[r >> 12 & 63] + n[r >> 6 & 63] + n[r & 63] } function h(r, e, t) { var n; var o = []; for (var f = e; f < t; f += 3) { n = (r[f] << 16) + (r[f + 1] << 8) + r[f + 2]; o.push(l(n)) } return o.join("") } function s(r) { var e; var t = r.length; var o = t % 3; var f = ""; var i = []; var a = 16383; for (var u = 0, d = t - o; u < d; u += a) { i.push(h(r, u, u + a > d ? d : u + a)) } if (o === 1) { e = r[t - 1]; f += n[e >> 2]; f += n[e << 4 & 63]; f += "==" } else { if (o === 2) { e = (r[t - 2] << 8) + r[t - 1]; f += n[e >> 10]; f += n[e >> 4 & 63]; f += n[e << 2 & 63]; f += "=" } } i.push(f); return i.join("") } }, {}] }, {}, [])("/") });
 
// const base64js = require('base64-js').Base64
/**
 * 国密SM4加密算法
 */
function SM4_Context() {
  this.mode = 1;
  this.isPadding = true;
  this.sk = new Array(32);
}
 
function SM4() {
  this.SM4_ENCRYPT = 1;
  this.SM4_DECRYPT = 0;
 
  var SboxTable = [0xd6, 0x90, 0xe9, 0xfe, 0xcc, 0xe1, 0x3d, 0xb7, 0x16, 0xb6, 0x14, 0xc2, 0x28, 0xfb, 0x2c, 0x05,
    0x2b, 0x67, 0x9a, 0x76, 0x2a, 0xbe, 0x04, 0xc3, 0xaa, 0x44, 0x13, 0x26, 0x49, 0x86, 0x06, 0x99,
    0x9c, 0x42, 0x50, 0xf4, 0x91, 0xef, 0x98, 0x7a, 0x33, 0x54, 0x0b, 0x43, 0xed, 0xcf, 0xac, 0x62,
    0xe4, 0xb3, 0x1c, 0xa9, 0xc9, 0x08, 0xe8, 0x95, 0x80, 0xdf, 0x94, 0xfa, 0x75, 0x8f, 0x3f, 0xa6,
    0x47, 0x07, 0xa7, 0xfc, 0xf3, 0x73, 0x17, 0xba, 0x83, 0x59, 0x3c, 0x19, 0xe6, 0x85, 0x4f, 0xa8,
    0x68, 0x6b, 0x81, 0xb2, 0x71, 0x64, 0xda, 0x8b, 0xf8, 0xeb, 0x0f, 0x4b, 0x70, 0x56, 0x9d, 0x35,
    0x1e, 0x24, 0x0e, 0x5e, 0x63, 0x58, 0xd1, 0xa2, 0x25, 0x22, 0x7c, 0x3b, 0x01, 0x21, 0x78, 0x87,
    0xd4, 0x00, 0x46, 0x57, 0x9f, 0xd3, 0x27, 0x52, 0x4c, 0x36, 0x02, 0xe7, 0xa0, 0xc4, 0xc8, 0x9e,
    0xea, 0xbf, 0x8a, 0xd2, 0x40, 0xc7, 0x38, 0xb5, 0xa3, 0xf7, 0xf2, 0xce, 0xf9, 0x61, 0x15, 0xa1,
    0xe0, 0xae, 0x5d, 0xa4, 0x9b, 0x34, 0x1a, 0x55, 0xad, 0x93, 0x32, 0x30, 0xf5, 0x8c, 0xb1, 0xe3,
    0x1d, 0xf6, 0xe2, 0x2e, 0x82, 0x66, 0xca, 0x60, 0xc0, 0x29, 0x23, 0xab, 0x0d, 0x53, 0x4e, 0x6f,
    0xd5, 0xdb, 0x37, 0x45, 0xde, 0xfd, 0x8e, 0x2f, 0x03, 0xff, 0x6a, 0x72, 0x6d, 0x6c, 0x5b, 0x51,
    0x8d, 0x1b, 0xaf, 0x92, 0xbb, 0xdd, 0xbc, 0x7f, 0x11, 0xd9, 0x5c, 0x41, 0x1f, 0x10, 0x5a, 0xd8,
    0x0a, 0xc1, 0x31, 0x88, 0xa5, 0xcd, 0x7b, 0xbd, 0x2d, 0x74, 0xd0, 0x12, 0xb8, 0xe5, 0xb4, 0xb0,
    0x89, 0x69, 0x97, 0x4a, 0x0c, 0x96, 0x77, 0x7e, 0x65, 0xb9, 0xf1, 0x09, 0xc5, 0x6e, 0xc6, 0x84,
    0x18, 0xf0, 0x7d, 0xec, 0x3a, 0xdc, 0x4d, 0x20, 0x79, 0xee, 0x5f, 0x3e, 0xd7, 0xcb, 0x39, 0x48];
 
  var FK = [0xa3b1bac6, 0x56aa3350, 0x677d9197, 0xb27022dc];
 
  var CK = [0x00070e15, 0x1c232a31, 0x383f464d, 0x545b6269,
    0x70777e85, 0x8c939aa1, 0xa8afb6bd, 0xc4cbd2d9,
    0xe0e7eef5, 0xfc030a11, 0x181f262d, 0x343b4249,
    0x50575e65, 0x6c737a81, 0x888f969d, 0xa4abb2b9,
    0xc0c7ced5, 0xdce3eaf1, 0xf8ff060d, 0x141b2229,
    0x30373e45, 0x4c535a61, 0x686f767d, 0x848b9299,
    0xa0a7aeb5, 0xbcc3cad1, 0xd8dfe6ed, 0xf4fb0209,
    0x10171e25, 0x2c333a41, 0x484f565d, 0x646b7279];
 
  this.GET_ULONG_BE = function (b, i) {
    return (b[i] & 0xff) << 24 | ((b[i + 1] & 0xff) << 16) | ((b[i + 2] & 0xff) << 8) | (b[i + 3] & 0xff) & 0xffffffff;
  }
 
  this.PUT_ULONG_BE = function (n, b, i) {
    var t1 = (0xFF & (n >> 24));
    var t2 = (0xFF & (n >> 16));
    var t3 = (0xFF & (n >> 8));
    var t4 = (0xFF & (n));
    b[i] = t1 > 128 ? t1 - 256 : t1;
    b[i + 1] = t2 > 128 ? t2 - 256 : t2;
    b[i + 2] = t3 > 128 ? t3 - 256 : t3;
    b[i + 3] = t4 > 128 ? t4 - 256 : t4;
  }
 
  this.SHL = function (x, n) {
    return (x & 0xFFFFFFFF) << n;
  }
 
  this.ROTL = function (x, n) {
    var s = this.SHL(x, n);
    var ss = x >> (32 - n);
    return this.SHL(x, n) | x >> (32 - n);
  }
 
 
  this.sm4Lt = function (ka) {
    var bb = 0;
    var c = 0;
    var a = new Array(4);
    var b = new Array(4);
    this.PUT_ULONG_BE(ka, a, 0);
    b[0] = this.sm4Sbox(a[0]);
    b[1] = this.sm4Sbox(a[1]);
    b[2] = this.sm4Sbox(a[2]);
    b[3] = this.sm4Sbox(a[3]);
    bb = this.GET_ULONG_BE(b, 0);
    c = bb ^ this.ROTL(bb, 2) ^ this.ROTL(bb, 10) ^ this.ROTL(bb, 18) ^ this.ROTL(bb, 24);
    return c;
  }
 
  this.sm4F = function (x0, x1, x2, x3, rk) {
    return x0 ^ this.sm4Lt(x1 ^ x2 ^ x3 ^ rk);
  }
 
  this.sm4CalciRK = function (ka) {
    var bb = 0;
    var rk = 0;
    var a = new Array(4);
    var b = new Array(4);
    this.PUT_ULONG_BE(ka, a, 0);
    b[0] = this.sm4Sbox(a[0]);
    b[1] = this.sm4Sbox(a[1]);
    b[2] = this.sm4Sbox(a[2]);
    b[3] = this.sm4Sbox(a[3]);
    bb = this.GET_ULONG_BE(b, 0);
    rk = bb ^ this.ROTL(bb, 13) ^ this.ROTL(bb, 23);
    return rk;
  }
 
 
 
  this.sm4Sbox = function (inch) {
    var i = inch & 0xFF;
    var retVal = SboxTable[i];
    return retVal > 128 ? retVal - 256 : retVal;
  }
 
  this.sm4_setkey_enc = function (ctx, key) {
    if (ctx == null) {
      alert("ctx is null!");
      return false;
    }
    if (key == null || key.length != 16) {
      alert("key error!");
      return false;
    }
    ctx.mode = this.SM4_ENCRYPT;
    this.sm4_setkey(ctx.sk, key);
 
  };
  //生成解密密钥
  this.sm4_setkey_dec = function (ctx, key) {
    if (ctx == null) {
      Error("ctx is null!");
    }
 
    if (key == null || key.length != 16) {
      Error("key error!");
    }
 
    ctx.mode = this.SM4_DECRYPT;
    this.sm4_setkey(ctx.sk, key);
    ctx.sk = ctx.sk.reverse();
  }
 
 
  this.sm4_setkey = function (SK, key) {
    var MK = new Array(4);
    var k = new Array(36);
    var i = 0;
    MK[0] = this.GET_ULONG_BE(key, 0);
    MK[1] = this.GET_ULONG_BE(key, 4);
    MK[2] = this.GET_ULONG_BE(key, 8);
    MK[3] = this.GET_ULONG_BE(key, 12);
    k[0] = MK[0] ^ FK[0];
    k[1] = MK[1] ^ FK[1];
    k[2] = MK[2] ^ FK[2];
    k[3] = MK[3] ^ FK[3];
    for (var i = 0; i < 32; i++) {
      k[(i + 4)] = (k[i] ^ this.sm4CalciRK(k[(i + 1)] ^ k[(i + 2)] ^ k[(i + 3)] ^ CK[i]));
      SK[i] = k[(i + 4)];
    }
 
  }
  this.padding = function (input, mode) {
    if (input == null) {
      return null;
    }
    var ret = null;
    if (mode == this.SM4_ENCRYPT) {
      var p = parseInt(16 - input.length % 16);
      ret = input.slice(0);
      for (var i = 0; i < p; i++) {
        ret[input.length + i] = p;
      }
    } else {
      var p = input[input.length - 1];
      ret = input.slice(0, input.length - p);
    }
    return ret;
  }
  this.sm4_one_round = function (sk, input, output) {
    var i = 0;
    var ulbuf = new Array(36);
    ulbuf[0] = this.GET_ULONG_BE(input, 0);
    ulbuf[1] = this.GET_ULONG_BE(input, 4);
    ulbuf[2] = this.GET_ULONG_BE(input, 8);
    ulbuf[3] = this.GET_ULONG_BE(input, 12);
    while (i < 32) {
      ulbuf[(i + 4)] = this.sm4F(ulbuf[i], ulbuf[(i + 1)], ulbuf[(i + 2)], ulbuf[(i + 3)], sk[i]);
      i++;
    }
    this.PUT_ULONG_BE(ulbuf[35], output, 0);
    this.PUT_ULONG_BE(ulbuf[34], output, 4);
    this.PUT_ULONG_BE(ulbuf[33], output, 8);
    this.PUT_ULONG_BE(ulbuf[32], output, 12);
 
  }
 
  this.sm4_crypt_ecb = function (ctx, input) {
    if (input == null) {
      alert("input is null!");
    }
    if ((ctx.isPadding) && (ctx.mode == this.SM4_ENCRYPT)) {
      input = this.padding(input, this.SM4_ENCRYPT);
    }
 
    var i = 0;
    var length = input.length;
    var bous = new Array();
    for (; length > 0; length -= 16) {
      var out = new Array(16);
      var ins = input.slice(i * 16, (16 * (i + 1)));
      this.sm4_one_round(ctx.sk, ins, out)
      bous = bous.concat(out);
      i++;
    }
 
    var output = bous;
    if (ctx.isPadding && ctx.mode == this.SM4_DECRYPT) {
      output = this.padding(output, this.SM4_DECRYPT);
    }
    for (var i = 0; i < output.length; i++) {
      if (output[i] < 0) {
        output[i] = output[i] + 256;
      }
    }
    return output;
  }
 
  this.sm4_crypt_cbc = function (ctx, iv, input) {
    if (iv == null || iv.length != 16) {
      alert("iv error!");
    }
 
    if (input == null) {
      alert("input is null!");
    }
 
    if (ctx.isPadding && ctx.mode == this.SM4_ENCRYPT) {
      input = this.padding(input, this.SM4_ENCRYPT);
    }
 
    var i = 0;
    var length = input.length;
    var bous = new Array();
    if (ctx.mode == this.SM4_ENCRYPT) {
      var k = 0;
      for (; length > 0; length -= 16) {
        var out = new Array(16);
        var out1 = new Array(16);
        var ins = input.slice(k * 16, (16 * (k + 1)));
 
        for (i = 0; i < 16; i++) {
          out[i] = (ins[i] ^ iv[i]);
        }
        this.sm4_one_round(ctx.sk, out, out1);
        iv = out1.slice(0, 16);
        bous = bous.concat(out1);
        k++;
      }
    }
    else {
      var temp = [];
      var k = 0;
      for (; length > 0; length -= 16) {
        var out = new Array(16);
        var out1 = new Array(16);
        var ins = input.slice(k * 16, (16 * (k + 1)));
        temp = ins.slice(0, 16);
        sm4_one_round(ctx.sk, ins, out);
        for (i = 0; i < 16; i++) {
          out1[i] = (out[i] ^ iv[i]);
        }
        iv = temp.slice(0, 16);
        bous = bous.concat(out1);
        k++;
      }
    }
 
    var output = bous;
    if (ctx.isPadding && ctx.mode == this.SM4_DECRYPT) {
      output = this.padding(output, this.SM4_DECRYPT);
    }
 
    for (var i = 0; i < output.length; i++) {
      if (output[i] < 0) {
        output[i] = output[i] + 256;
      }
    }
    return output;
  }
}
 
 
function SM4Util() {
 
  this.secretKey = "11HDESAAHIHHUGDZ";
  //this.iv = "UISwD9fW6cFh9SNS";
  this.iv = "";
  //this.hexString = false;
  //加密_ECB
  this.encryptData_ECB = function (plainText) {
    try {
      var sm4 = new SM4();
      var ctx = new SM4_Context();
      ctx.isPadding = true;
      ctx.mode = sm4.SM4_ENCRYPT;
      var keyBytes = stringToByte(this.secretKey);
      sm4.sm4_setkey_enc(ctx, keyBytes);
      var encrypted = sm4.sm4_crypt_ecb(ctx, stringToByte(plainText));
 
      var cipherText = base64js.fromByteArray(encrypted);
      if (cipherText != null && cipherText.trim().length > 0) {
        cipherText.replace(/(\s*|\t|\r|\n)/g, "");
      }
      return cipherText;
    } catch (e) {
      console.error(e);
      return null;
    }
 
  }
  //解密_ECB
  this.decryptData_ECB = function (cipherText) {
    try {
      var sm4 = new SM4();
      var ctx = new SM4_Context();
      ctx.isPadding = true;
      ctx.mode = sm4.SM4_DECRYPT;
      var keyBytes = stringToByte(this.secretKey);
      sm4.sm4_setkey_dec(ctx, keyBytes);
      var decrypted = sm4.sm4_crypt_ecb(ctx, base64js.toByteArray(cipherText));
      return utf8ByteToUnicodeStr(decrypted);
    } catch (e) {
      console.log(e)
      console.error(e);
      return null;
    }
  }
 
  this.encryptData_CBC = function (plainText) {
    try {
      var sm4 = new SM4();
      var ctx = new SM4_Context();
      ctx.isPadding = true;
      ctx.mode = sm4.SM4_ENCRYPT;
 
      var keyBytes = stringToByte(this.secretKey);
      var ivBytes = stringToByte(this.iv);
 
      sm4.sm4_setkey_enc(ctx, keyBytes);
      var encrypted = sm4.sm4_crypt_cbc(ctx, ivBytes, stringToByte(plainText));
      var cipherText = base64js.fromByteArray(encrypted);
      if (cipherText != null && cipherText.trim().length > 0) {
        cipherText.replace(/(\s*|\t|\r|\n)/g, "");
      }
      return cipherText;
    }
    catch (e) {
      console.error(e);
      return null;
    }
  }
 
  var stringToByte = function (str) {
    var bytes = new Array();
    var len, c;
    len = str.length;
    for (var i = 0; i < len; i++) {
      c = str.charCodeAt(i);
      if (c >= 0x010000 && c <= 0x10FFFF) {
        bytes.push(((c >> 18) & 0x07) | 0xF0);
        bytes.push(((c >> 12) & 0x3F) | 0x80);
        bytes.push(((c >> 6) & 0x3F) | 0x80);
        bytes.push((c & 0x3F) | 0x80);
      } else if (c >= 0x000800 && c <= 0x00FFFF) {
        bytes.push(((c >> 12) & 0x0F) | 0xE0);
        bytes.push(((c >> 6) & 0x3F) | 0x80);
        bytes.push((c & 0x3F) | 0x80);
      } else if (c >= 0x000080 && c <= 0x0007FF) {
        bytes.push(((c >> 6) & 0x1F) | 0xC0);
        bytes.push((c & 0x3F) | 0x80);
      } else {
        bytes.push(c & 0xFF);
      }
 
    }
    // console.log('bytes: '+bytes)
    return bytes;
  }
 
 
  var byteToString = function (arr) {
    if (typeof arr === 'string') {
      return arr;
    }
    var str = '',
      _arr = arr;
    for (var i = 0; i < _arr.length; i++) {
      var one = _arr[i].toString(2),
        v = one.match(/^1+?(?=0)/);
      if (v && one.length == 8) {
        var bytesLength = v[0].length;
        var store = _arr[i].toString(2).slice(7 - bytesLength);
        for (var st = 1; st < bytesLength; st++) {
          store += _arr[st + i].toString(2).slice(2);
        }
        str += String.fromCharCode(parseInt(store, 2));
        i += bytesLength - 1;
      } else {
        str += String.fromCharCode(_arr[i]);
      }
    }
    return str;
  }
  function utf8ByteToUnicodeStr(utf8Bytes){
    var unicodeStr ="";
    for (var pos = 0; pos < utf8Bytes.length;){
      var flag= utf8Bytes[pos];
      var unicode = 0 ;
      if ((flag >>>7) === 0 ) {
        unicodeStr+= String.fromCharCode(utf8Bytes[pos]);
        pos += 1;
 
      } else if ((flag &0xFC) === 0xFC ){
        unicode = (utf8Bytes[pos] & 0x3) << 30;
        unicode |= (utf8Bytes[pos+1] & 0x3F) << 24;
        unicode |= (utf8Bytes[pos+2] & 0x3F) << 18;
        unicode |= (utf8Bytes[pos+3] & 0x3F) << 12;
        unicode |= (utf8Bytes[pos+4] & 0x3F) << 6;
        unicode |= (utf8Bytes[pos+5] & 0x3F);
        unicodeStr+= String.fromCharCode(unicode) ;
        pos += 6;
 
      }else if ((flag &0xF8) === 0xF8 ){
        unicode = (utf8Bytes[pos] & 0x7) << 24;
        unicode |= (utf8Bytes[pos+1] & 0x3F) << 18;
        unicode |= (utf8Bytes[pos+2] & 0x3F) << 12;
        unicode |= (utf8Bytes[pos+3] & 0x3F) << 6;
        unicode |= (utf8Bytes[pos+4] & 0x3F);
        unicodeStr+= String.fromCharCode(unicode) ;
        pos += 5;
 
      } else if ((flag &0xF0) === 0xF0 ){
        unicode = (utf8Bytes[pos] & 0xF) << 18;
        unicode |= (utf8Bytes[pos+1] & 0x3F) << 12;
        unicode |= (utf8Bytes[pos+2] & 0x3F) << 6;
        unicode |= (utf8Bytes[pos+3] & 0x3F);
        unicodeStr+= String.fromCharCode(unicode) ;
        pos += 4;
 
      } else if ((flag &0xE0) === 0xE0 ){
        unicode = (utf8Bytes[pos] & 0x1F) << 12;;
        unicode |= (utf8Bytes[pos+1] & 0x3F) << 6;
        unicode |= (utf8Bytes[pos+2] & 0x3F);
        unicodeStr+= String.fromCharCode(unicode) ;
        pos += 3;
 
      } else if ((flag &0xC0) === 0xC0 ){ //110
        unicode = (utf8Bytes[pos] & 0x3F) << 6;
        unicode |= (utf8Bytes[pos+1] & 0x3F);
        unicodeStr+= String.fromCharCode(unicode) ;
        pos += 2;
 
      } else{
        unicodeStr+= String.fromCharCode(utf8Bytes[pos]);
        pos += 1;
      }
    }
    return unicodeStr;
  }
};
 module.exports={
	 s4:new SM4Util()
 }

3. sm4.js文件重点修改地方如下

4.页面使用
4.1引入 import {s4} from “…/…/static/SM/sm4.js”
4.2使用 s4.encryptData_ECB(that.imgList[2])
注意：encryptData_ECB是加密方法，decryptData_ECB是解密方法