javascript实现des解密加密全过程

2014-04-03 34

//Paul Tero, July 2001 
//http://www.tero.co.uk/des/ 
// 
//Optimised for performance with large blocks by Michael Hayworth, November 2001 
//http://www.netdealing.com 
// 
//THIS SOFTWARE IS PROVIDED "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 AUTHOR 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. //des 
//this takes the key, the message, and whether to encrypt or decrypt 
function des (key, message, encrypt, mode, iv, padding) { 
//declaring this locally speeds things up a bit 
var spfunction1 = new Array (0x1010400,0,0x10000,0x1010404,0x1010004,0x10404,0x4,0x10000,0x400,0x1010400,0x1010404,0x400,0x1000404,0x1010004,0x1000000,0x4,0x404,0x1000400,0x1000400,0x10400,0x10400,0x1010000,0x1010000,0x1000404,0x10004,0x1000004,0x1000004,0x10004,0,0x404,0x10404,0x1000000,0x10000,0x1010404,0x4,0x1010000,0x1010400,0x1000000,0x1000000,0x400,0x1010004,0x10000,0x10400,0x1000004,0x400,0x4,0x1000404,0x10404,0x1010404,0x10004,0x1010000,0x1000404,0x1000004,0x404,0x10404,0x1010400,0x404,0x1000400,0x1000400,0,0x10004,0x10400,0,0x1010004); 
var spfunction2 = new Array (-0x7fef7fe0,-0x7fff8000,0x8000,0x108020,0x100000,0x20,-0x7fefffe0,-0x7fff7fe0,-0x7fffffe0,-0x7fef7fe0,-0x7fef8000,-0x80000000,-0x7fff8000,0x100000,0x20,-0x7fefffe0,0x108000,0x100020,-0x7fff7fe0,0,-0x80000000,0x8000,0x108020,-0x7ff00000,0x100020,-0x7fffffe0,0,0x108000,0x8020,-0x7fef8000,-0x7ff00000,0x8020,0,0x108020,-0x7fefffe0,0x100000,-0x7fff7fe0,-0x7ff00000,-0x7fef8000,0x8000,-0x7ff00000,-0x7fff8000,0x20,-0x7fef7fe0,0x108020,0x20,0x8000,-0x80000000,0x8020,-0x7fef8000,0x100000,-0x7fffffe0,0x100020,-0x7fff7fe0,-0x7fffffe0,0x100020,0x108000,0,-0x7fff8000,0x8020,-0x80000000,-0x7fefffe0,-0x7fef7fe0,0x108000); 
var spfunction3 = new Array (0x208,0x8020200,0,0x8020008,0x8000200,0,0x20208,0x8000200,0x20008,0x8000008,0x8000008,0x20000,0x8020208,0x20008,0x8020000,0x208,0x8000000,0x8,0x8020200,0x200,0x20200,0x8020000,0x8020008,0x20208,0x8000208,0x20200,0x20000,0x8000208,0x8,0x8020208,0x200,0x8000000,0x8020200,0x8000000,0x20008,0x208,0x20000,0x8020200,0x8000200,0,0x200,0x20008,0x8020208,0x8000200,0x8000008,0x200,0,0x8020008,0x8000208,0x20000,0x8000000,0x8020208,0x8,0x20208,0x20200,0x8000008,0x8020000,0x8000208,0x208,0x8020000,0x20208,0x8,0x8020008,0x20200); 
var spfunction4 = new Array (0x802001,0x2081,0x2081,0x80,0x802080,0x800081,0x800001,0x2001,0,0x802000,0x802000,0x802081,0x81,0,0x800080,0x800001,0x1,0x2000,0x800000,0x802001,0x80,0x800000,0x2001,0x2080,0x800081,0x1,0x2080,0x800080,0x2000,0x802080,0x802081,0x81,0x800080,0x800001,0x802000,0x802081,0x81,0,0,0x802000,0x2080,0x800080,0x800081,0x1,0x802001,0x2081,0x2081,0x80,0x802081,0x81,0x1,0x2000,0x800001,0x2001,0x802080,0x800081,0x2001,0x2080,0x800000,0x802001,0x80,0x800000,0x2000,0x802080); 
var spfunction5 = new Array (0x100,0x2080100,0x2080000,0x42000100,0x80000,0x100,0x40000000,0x2080000,0x40080100,0x80000,0x2000100,0x40080100,0x42000100,0x42080000,0x80100,0x40000000,0x2000000,0x40080000,0x40080000,0,0x40000100,0x42080100,0x42080100,0x2000100,0x42080000,0x40000100,0,0x42000000,0x2080100,0x2000000,0x42000000,0x80100,0x80000,0x42000100,0x100,0x2000000,0x40000000,0x2080000,0x42000100,0x40080100,0x2000100,0x40000000,0x42080000,0x2080100,0x40080100,0x100,0x2000000,0x42080000,0x42080100,0x80100,0x42000000,0x42080100,0x2080000,0,0x40080000,0x42000000,0x80100,0x2000100,0x40000100,0x80000,0,0x40080000,0x2080100,0x40000100); 
var spfunction6 = new Array (0x20000010,0x20400000,0x4000,0x20404010,0x20400000,0x10,0x20404010,0x400000,0x20004000,0x404010,0x400000,0x20000010,0x400010,0x20004000,0x20000000,0x4010,0,0x400010,0x20004010,0x4000,0x404000,0x20004010,0x10,0x20400010,0x20400010,0,0x404010,0x20404000,0x4010,0x404000,0x20404000,0x20000000,0x20004000,0x10,0x20400010,0x404000,0x20404010,0x400000,0x4010,0x20000010,0x400000,0x20004000,0x20000000,0x4010,0x20000010,0x20404010,0x404000,0x20400000,0x404010,0x20404000,0,0x20400010,0x10,0x4000,0x20400000,0x404010,0x4000,0x400010,0x20004010,0,0x20404000,0x20000000,0x400010,0x20004010); 
var spfunction7 = new Array (0x200000,0x4200002,0x4000802,0,0x800,0x4000802,0x200802,0x4200800,0x4200802,0x200000,0,0x4000002,0x2,0x4000000,0x4200002,0x802,0x4000800,0x200802,0x200002,0x4000800,0x4000002,0x4200000,0x4200800,0x200002,0x4200000,0x800,0x802,0x4200802,0x200800,0x2,0x4000000,0x200800,0x4000000,0x200800,0x200000,0x4000802,0x4000802,0x4200002,0x4200002,0x2,0x200002,0x4000000,0x4000800,0x200000,0x4200800,0x802,0x200802,0x4200800,0x802,0x4000002,0x4200802,0x4200000,0x200800,0,0x2,0x4200802,0,0x200802,0x4200000,0x800,0x4000002,0x4000800,0x800,0x200002); 
var spfunction8 = new Array (0x10001040,0x1000,0x40000,0x10041040,0x10000000,0x10001040,0x40,0x10000000,0x40040,0x10040000,0x10041040,0x41000,0x10041000,0x41040,0x1000,0x40,0x10040000,0x10000040,0x10001000,0x1040,0x41000,0x40040,0x10040040,0x10041000,0x1040,0,0,0x10040040,0x10000040,0x10001000,0x41040,0x40000,0x41040,0x40000,0x10041000,0x1000,0x40,0x10040040,0x1000,0x41040,0x10001000,0x40,0x10000040,0x10040000,0x10040040,0x10000000,0x40000,0x10001040,0,0x10041040,0x40040,0x10000040,0x10040000,0x10001000,0x10001040,0,0x10041040,0x41000,0x41000,0x1040,0x1040,0x40040,0x10000000,0x10041000); 
//create the 16 or 48 subkeys we will need 
var keys = des_createKeys (key); 
var m=0, i, j, temp, temp2, right1, right2, left, right, looping; 
var cbcleft, cbcleft2, cbcright, cbcright2 
var endloop, loopinc; 
var len = message.length; 
var chunk = 0; 
//set up the loops for single and triple des 
var iterations = keys.length == 32 ? 3 : 9; //single or triple des 
if (iterations == 3) {looping = encrypt ? new Array (0, 32, 2) : new Array (30, -2, -2);} 
else {looping = encrypt ? new Array (0, 32, 2, 62, 30, -2, 64, 96, 2) : new Array (94, 62, -2, 32, 64, 2, 30, -2, -2);} 
//pad the message depending on the padding parameter 
if (padding == 2) message += " "; //pad the message with spaces 
else if (padding == 1) {temp = 8-(len%8); message += String.fromCharCode (temp,temp,temp,temp,temp,temp,temp,temp); if (temp==8) len+=8;} //PKCS7 padding 
else if (!padding) message += "\0\0\0\0\0\0\0\0"; //pad the message out with null bytes 
//store the result here 
result = ""; 
tempresult = ""; 
if (mode == 1) { //CBC mode 
cbcleft = (iv.charCodeAt(m++) << 24) | (iv.charCodeAt(m++) << 16) | (iv.charCodeAt(m++) << 8) | iv.charCodeAt(m++); 
cbcright = (iv.charCodeAt(m++) << 24) | (iv.charCodeAt(m++) << 16) | (iv.charCodeAt(m++) << 8) | iv.charCodeAt(m++); 
m=0; 
} 
//loop through each 64 bit chunk of the message 
while (m < len) { 
left = (message.charCodeAt(m++) << 24) | (message.charCodeAt(m++) << 16) | (message.charCodeAt(m++) << 8) | message.charCodeAt(m++); 
right = (message.charCodeAt(m++) << 24) | (message.charCodeAt(m++) << 16) | (message.charCodeAt(m++) << 8) | message.charCodeAt(m++); 
//for Cipher Block Chaining mode, xor the message with the previous result 
if (mode == 1) {if (encrypt) {left ^= cbcleft; right ^= cbcright;} else {cbcleft2 = cbcleft; cbcright2 = cbcright; cbcleft = left; cbcright = right;}} 
//first each 64 but chunk of the message must be permuted according to IP 
temp = ((left >>> 4) ^ right) & 0x0f0f0f0f; right ^= temp; left ^= (temp << 4); 
temp = ((left >>> 16) ^ right) & 0x0000ffff; right ^= temp; left ^= (temp << 16); 
temp = ((right >>> 2) ^ left) & 0x33333333; left ^= temp; right ^= (temp << 2); 
temp = ((right >>> 8) ^ left) & 0x00ff00ff; left ^= temp; right ^= (temp << 8); 
temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1); 
left = ((left << 1) | (left >>> 31)); 
right = ((right << 1) | (right >>> 31)); 
//do this either 1 or 3 times for each chunk of the message 
for (j=0; j<iterations; j+=3) { 
endloop = looping[j+1]; 
loopinc = looping[j+2]; 
//now go through and perform the encryption or decryption 
for (i=looping[j]; i!=endloop; i+=loopinc) { //for efficiency 
right1 = right ^ keys[i]; 
right2 = ((right >>> 4) | (right << 28)) ^ keys[i+1]; 
//the result is attained by passing these bytes through the S selection functions 
temp = left; 
left = right; 
right = temp ^ (spfunction2[(right1 >>> 24) & 0x3f] | spfunction4[(right1 >>> 16) & 0x3f] 
| spfunction6[(right1 >>> 8) & 0x3f] | spfunction8[right1 & 0x3f] 
| spfunction1[(right2 >>> 24) & 0x3f] | spfunction3[(right2 >>> 16) & 0x3f] 
| spfunction5[(right2 >>> 8) & 0x3f] | spfunction7[right2 & 0x3f]); 
} 
temp = left; left = right; right = temp; //unreverse left and right 
} //for either 1 or 3 iterations 
//move then each one bit to the right 
left = ((left >>> 1) | (left << 31)); 
right = ((right >>> 1) | (right << 31)); 
//now perform IP-1, which is IP in the opposite direction 
temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1); 
temp = ((right >>> 8) ^ left) & 0x00ff00ff; left ^= temp; right ^= (temp << 8); 
temp = ((right >>> 2) ^ left) & 0x33333333; left ^= temp; right ^= (temp << 2); 
temp = ((left >>> 16) ^ right) & 0x0000ffff; right ^= temp; left ^= (temp << 16); 
temp = ((left >>> 4) ^ right) & 0x0f0f0f0f; right ^= temp; left ^= (temp << 4); 
//for Cipher Block Chaining mode, xor the message with the previous result 
if (mode == 1) {if (encrypt) {cbcleft = left; cbcright = right;} else {left ^= cbcleft2; right ^= cbcright2;}} 
tempresult += String.fromCharCode ((left>>>24), ((left>>>16) & 0xff), ((left>>>8) & 0xff), (left & 0xff), (right>>>24), ((right>>>16) & 0xff), ((right>>>8) & 0xff), (right & 0xff)); 
chunk += 8; 
if (chunk == 512) {result += tempresult; tempresult = ""; chunk = 0;} 
} //for every 8 characters, or 64 bits in the message 
//return the result as an array 
return result + tempresult; 
} //end of des 

//des_createKeys 
//this takes as input a 64 bit key (even though only 56 bits are used) 
//as an array of 2 integers, and returns 16 48 bit keys 
function des_createKeys (key) { 
//declaring this locally speeds things up a bit 
pc2bytes0 = new Array (0,0x4,0x20000000,0x20000004,0x10000,0x10004,0x20010000,0x20010004,0x200,0x204,0x20000200,0x20000204,0x10200,0x10204,0x20010200,0x20010204); 
pc2bytes1 = new Array (0,0x1,0x100000,0x100001,0x4000000,0x4000001,0x4100000,0x4100001,0x100,0x101,0x100100,0x100101,0x4000100,0x4000101,0x4100100,0x4100101); 
pc2bytes2 = new Array (0,0x8,0x800,0x808,0x1000000,0x1000008,0x1000800,0x1000808,0,0x8,0x800,0x808,0x1000000,0x1000008,0x1000800,0x1000808); 
pc2bytes3 = new Array (0,0x200000,0x8000000,0x8200000,0x2000,0x202000,0x8002000,0x8202000,0x20000,0x220000,0x8020000,0x8220000,0x22000,0x222000,0x8022000,0x8222000); 
pc2bytes4 = new Array (0,0x40000,0x10,0x40010,0,0x40000,0x10,0x40010,0x1000,0x41000,0x1010,0x41010,0x1000,0x41000,0x1010,0x41010); 
pc2bytes5 = new Array (0,0x400,0x20,0x420,0,0x400,0x20,0x420,0x2000000,0x2000400,0x2000020,0x2000420,0x2000000,0x2000400,0x2000020,0x2000420); 
pc2bytes6 = new Array (0,0x10000000,0x80000,0x10080000,0x2,0x10000002,0x80002,0x10080002,0,0x10000000,0x80000,0x10080000,0x2,0x10000002,0x80002,0x10080002); 
pc2bytes7 = new Array (0,0x10000,0x800,0x10800,0x20000000,0x20010000,0x20000800,0x20010800,0x20000,0x30000,0x20800,0x30800,0x20020000,0x20030000,0x20020800,0x20030800); 
pc2bytes8 = new Array (0,0x40000,0,0x40000,0x2,0x40002,0x2,0x40002,0x2000000,0x2040000,0x2000000,0x2040000,0x2000002,0x2040002,0x2000002,0x2040002); 
pc2bytes9 = new Array (0,0x10000000,0x8,0x10000008,0,0x10000000,0x8,0x10000008,0x400,0x10000400,0x408,0x10000408,0x400,0x10000400,0x408,0x10000408); 
pc2bytes10 = new Array (0,0x20,0,0x20,0x100000,0x100020,0x100000,0x100020,0x2000,0x2020,0x2000,0x2020,0x102000,0x102020,0x102000,0x102020); 
pc2bytes11 = new Array (0,0x1000000,0x200,0x1000200,0x200000,0x1200000,0x200200,0x1200200,0x4000000,0x5000000,0x4000200,0x5000200,0x4200000,0x5200000,0x4200200,0x5200200); 
pc2bytes12 = new Array (0,0x1000,0x8000000,0x8001000,0x80000,0x81000,0x8080000,0x8081000,0x10,0x1010,0x8000010,0x8001010,0x80010,0x81010,0x8080010,0x8081010); 
pc2bytes13 = new Array (0,0x4,0x100,0x104,0,0x4,0x100,0x104,0x1,0x5,0x101,0x105,0x1,0x5,0x101,0x105); 
//how many iterations (1 for des, 3 for triple des) 
var iterations = key.length > 8 ? 3 : 1; //changed by Paul 16/6/2007 to use Triple DES for 9+ byte keys 
//stores the return keys 
var keys = new Array (32 * iterations); 
//now define the left shifts which need to be done 
var shifts = new Array (0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0); 
//other variables 
var lefttemp, righttemp, m=0, n=0, temp; 
for (var j=0; j<iterations; j++) { //either 1 or 3 iterations 
left = (key.charCodeAt(m++) << 24) | (key.charCodeAt(m++) << 16) | (key.charCodeAt(m++) << 8) | key.charCodeAt(m++); 
right = (key.charCodeAt(m++) << 24) | (key.charCodeAt(m++) << 16) | (key.charCodeAt(m++) << 8) | key.charCodeAt(m++); 
temp = ((left >>> 4) ^ right) & 0x0f0f0f0f; right ^= temp; left ^= (temp << 4); 
temp = ((right >>> -16) ^ left) & 0x0000ffff; left ^= temp; right ^= (temp << -16); 
temp = ((left >>> 2) ^ right) & 0x33333333; right ^= temp; left ^= (temp << 2); 
temp = ((right >>> -16) ^ left) & 0x0000ffff; left ^= temp; right ^= (temp << -16); 
temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1); 
temp = ((right >>> 8) ^ left) & 0x00ff00ff; left ^= temp; right ^= (temp << 8); 
temp = ((left >>> 1) ^ right) & 0x55555555; right ^= temp; left ^= (temp << 1); 
//the right side needs to be shifted and to get the last four bits of the left side 
temp = (left << 8) | ((right >>> 20) & 0x000000f0); 
//left needs to be put upside down 
left = (right << 24) | ((right << 8) & 0xff0000) | ((right >>> 8) & 0xff00) | ((right >>> 24) & 0xf0); 
right = temp; 
//now go through and perform these shifts on the left and right keys 
for (var i=0; i < shifts.length; i++) { 
//shift the keys either one or two bits to the left 
if (shifts[i]) {left = (left << 2) | (left >>> 26); right = (right << 2) | (right >>> 26);} 
else {left = (left << 1) | (left >>> 27); right = (right << 1) | (right >>> 27);} 
left &= -0xf; right &= -0xf; 
//now apply PC-2, in such a way that E is easier when encrypting or decrypting 
//this conversion will look like PC-2 except only the last 6 bits of each byte are used 
//rather than 48 consecutive bits and the order of lines will be according to 
//how the S selection functions will be applied: S2, S4, S6, S8, S1, S3, S5, S7 
lefttemp = pc2bytes0[left >>> 28] | pc2bytes1[(left >>> 24) & 0xf] 
| pc2bytes2[(left >>> 20) & 0xf] | pc2bytes3[(left >>> 16) & 0xf] 
| pc2bytes4[(left >>> 12) & 0xf] | pc2bytes5[(left >>> 8) & 0xf] 
| pc2bytes6[(left >>> 4) & 0xf]; 
righttemp = pc2bytes7[right >>> 28] | pc2bytes8[(right >>> 24) & 0xf] 
| pc2bytes9[(right >>> 20) & 0xf] | pc2bytes10[(right >>> 16) & 0xf] 
| pc2bytes11[(right >>> 12) & 0xf] | pc2bytes12[(right >>> 8) & 0xf] 
| pc2bytes13[(right >>> 4) & 0xf]; 
temp = ((righttemp >>> 16) ^ lefttemp) & 0x0000ffff; 
keys[n++] = lefttemp ^ temp; keys[n++] = righttemp ^ (temp << 16); 
} 
} //for each iterations 
//return the keys we've created 
return keys; 
} //end of des_createKeys 

////////////////////////////// TEST ////////////////////////////// 
function stringToHex (s) { 
var r = "0x"; 
var hexes = new Array ("0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"); 
for (var i=0; i<s.length; i++) {r += hexes [s.charCodeAt(i) >> 4] + hexes [s.charCodeAt(i) & 0xf];} 
return r; 
} 
function hexToString (h) { 
var r = ""; 
for (var i= (h.substr(0, 2)=="0x")?2:0; i<h.length; i+=2) {r += String.fromCharCode (parseInt (h.substr (i, 2), 16));} 
return r; 
} 
var key = "this is a 24 byte key !!"; 
var message = "This is a test message"; 
var ciphertext = des (key, message, 1, 0); 
document.writeln ("DES Test: " + stringToHex (ciphertext));
展开阅读全文

更多Javascript文章

javascript中注册和移除事件的4种方式
Mar 20 45
js解决弹窗问题实现班级跳转DIV示例
Jan 06 37
JavaScript实现自动对页面上敏感词进行屏蔽的方法
Jul 27 49
JS数组排序方法实例分析
Dec 16 39
JavaScript订单操作小程序完整版
Jun 23 35
Vue程序化的事件监听器(实例方案详解)
Jan 07 40
vue 获取url里参数的两种方法小结
Nov 12 50
手机访问当前页面