des.js: remove decrypt and simplify.

The decrypt functionality is never used so remove it. Also, we can
assume that we are always DES encrypting 16 characters which allows
several things to be simplified in DES.

Overall this removes about 80 lines of code.
This commit is contained in:
Joel Martin 2010-09-29 14:48:19 -05:00
parent a679a97d1b
commit 12d2e7c192
2 changed files with 51 additions and 129 deletions

View File

@ -83,34 +83,20 @@
var DES = { var DES = {
// Tables, permutations, S-boxes, etc. // Tables, permutations, S-boxes, etc.
bytebit : [0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80], bytebit : [0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80],
bigbyte : [ 0x800000, 0x400000, 0x200000, 0x100000, bigbyte : [ 0x800000, 0x400000, 0x200000, 0x100000,
0x080000, 0x040000, 0x020000, 0x010000, 0x008000, 0x004000, 0x080000, 0x040000, 0x020000, 0x010000, 0x008000, 0x004000,
0x002000, 0x001000, 0x000800, 0x000400, 0x000200, 0x000100, 0x002000, 0x001000, 0x000800, 0x000400, 0x000200, 0x000100,
0x000080, 0x000040, 0x000020, 0x000010, 0x000008, 0x000004, 0x000080, 0x000040, 0x000020, 0x000010, 0x000008, 0x000004,
0x000002, 0x000001], 0x000002, 0x000001],
pc1 : [ 56, 48, 40, 32, pc1 : [56,48,40,32,24,16, 8, 0,57,49,41,33,25,17, 9, 1,
24, 16, 8, 0, 57, 49, 58,50,42,34,26,18,10, 2,59,51,43,35,62,54,46,38,
41, 33, 25, 17, 9, 1, 30,22,14,6, 61,53,45,37,29,21,13, 5,60,52,44,36,
58, 50, 42, 34, 26, 18, 28,20,12, 4,27,19,11, 3],
10, 2, 59, 51, 43, 35, pc2 : [13,16,10,23, 0, 4, 2,27,14, 5,20, 9,22,18,11, 3,
62, 54, 46, 38, 30, 22, 25, 7,15, 6,26,19,12, 1,40,51,30,36,46,54,29,39,
14, 6, 61, 53, 45, 37, 50,44,32,47,43,48,38,55,33,52,45,41,49,35,28,31 ],
29, 21, 13, 5, 60, 52, totrot : [ 1, 2, 4, 6, 8,10,12,14,15,17,19,21,23,25,27,28],
44, 36, 28, 20, 12, 4,
27, 19, 11, 3 ],
totrot : [ 1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21,
23, 25, 27, 28],
pc2 : [ 13, 16, 10, 23,
0, 4, 2, 27, 14, 5,
20, 9, 22, 18, 11, 3,
25, 7, 15, 6, 26, 19,
12, 1, 40, 51, 30, 36,
46, 54, 29, 39, 50, 44,
32, 47, 43, 48, 38, 55,
33, 52, 45, 41, 49, 35,
28, 31 ],
SP1 : [ 0x01010400, 0x00000000, 0x00010000, SP1 : [ 0x01010400, 0x00000000, 0x00010000,
0x01010404, 0x01010004, 0x00010404, 0x00000004, 0x00010000, 0x01010404, 0x01010004, 0x00010404, 0x00000004, 0x00010000,
0x00000400, 0x01010400, 0x01010404, 0x00000400, 0x01000404, 0x00000400, 0x01010400, 0x01010404, 0x00000400, 0x01000404,
@ -224,26 +210,12 @@ var DES = {
0x00041000, 0x00001040, 0x00001040, 0x00040040, 0x10000000, 0x00041000, 0x00001040, 0x00001040, 0x00040040, 0x10000000,
0x10041000], 0x10041000],
// Key routines. keys : [],
encryptKeys : [], // Set the key.
decryptKeys : [], setKeys : function(keyBlock) {
var i, j, l, m, n, pc1m = [], pcr = [], kn = [],
// / Set the key. raw0, raw1, rawi, KnLi;
setKeys : function(key) {
DES.encryptKeys = new Array(32);
DES.decryptKeys = new Array(32);
DES.deskey(key, true, DES.encryptKeys);
DES.deskey(key, false, DES.decryptKeys);
},
// Turn an 8-byte key into internal keys.
deskey : function(keyBlock, encrypting, KnL) {
var i, j, l, m, n,
pc1m = new Array(56),
pcr = new Array(56),
kn = new Array(32);
for (j = 0; j < 56; ++j) { for (j = 0; j < 56; ++j) {
l = DES.pc1[j]; l = DES.pc1[j];
@ -252,11 +224,7 @@ var DES = {
} }
for (i = 0; i < 16; ++i) { for (i = 0; i < 16; ++i) {
if (encrypting) { m = i << 1;
m = i << 1;
} else {
m = (15- i) << 1;
}
n = m + 1; n = m + 1;
kn[m] = kn[n] = 0; kn[m] = kn[n] = 0;
for (j = 0; j < 28; ++j) { for (j = 0; j < 28; ++j) {
@ -284,56 +252,33 @@ var DES = {
} }
} }
} }
DES.cookey(kn, KnL);
},
cookey: function(raw, KnL) {
var raw0, raw1,
rawi, KnLi,
i;
// cookey
for (i = 0, rawi = 0, KnLi = 0; i < 16; ++i) { for (i = 0, rawi = 0, KnLi = 0; i < 16; ++i) {
raw0 = raw[rawi++]; raw0 = kn[rawi++];
raw1 = raw[rawi++]; raw1 = kn[rawi++];
KnL[KnLi] = (raw0 & 0x00fc0000) << 6; DES.keys[KnLi] = (raw0 & 0x00fc0000) << 6;
KnL[KnLi] |= (raw0 & 0x00000fc0) << 10; DES.keys[KnLi] |= (raw0 & 0x00000fc0) << 10;
KnL[KnLi] |= (raw1 & 0x00fc0000) >>> 10; DES.keys[KnLi] |= (raw1 & 0x00fc0000) >>> 10;
KnL[KnLi] |= (raw1 & 0x00000fc0) >>> 6; DES.keys[KnLi] |= (raw1 & 0x00000fc0) >>> 6;
++KnLi; ++KnLi;
KnL[KnLi] = (raw0 & 0x0003f000) << 12; DES.keys[KnLi] = (raw0 & 0x0003f000) << 12;
KnL[KnLi] |= (raw0 & 0x0000003f) << 16; DES.keys[KnLi] |= (raw0 & 0x0000003f) << 16;
KnL[KnLi] |= (raw1 & 0x0003f000) >>> 4; DES.keys[KnLi] |= (raw1 & 0x0003f000) >>> 4;
KnL[KnLi] |= (raw1 & 0x0000003f); DES.keys[KnLi] |= (raw1 & 0x0000003f);
++KnLi; ++KnLi;
} }
}, },
// Block encryption routines. // Encrypt 8 bytes of text starting at offset
encrypt8: function(text, offset) {
var i, b = text, o, outInts =[],
fval, work, right, leftt, round, keysi = 0;
// / Encrypt a block of eight bytes. // Squash 8 bytes down to 2 ints
encrypt: function(clearText, clearOff, cipherText, cipherOff) { o = offset;
var tempInts = new Array(12); leftt = b[o++]<<24 | b[o++]<<16 | b[o++]<<8 | b[o++];
DES.squashBytesToInts(clearText, clearOff, tempInts, 0, 2); right = b[o++]<<24 | b[o++]<<16 | b[o++]<<8 | b[o++];
DES.des(tempInts, tempInts, DES.encryptKeys);
DES.spreadIntsToBytes(tempInts, 0, cipherText, cipherOff, 2);
},
// / Decrypt a block of eight bytes.
decrypt: function(cipherText, cipherOff, clearText, clearOff) {
var tempInts = new Array(12);
DES.squashBytesToInts(cipherText, cipherOff, tempInts, 0, 2);
DES.des(tempInts, tempInts, DES.decryptKeys);
DES.spreadIntsToBytes(tempInts, 0, clearText, clearOff, 2);
},
// The DES function.
des: function(inInts, outInts, keys) {
var fval, work, right, leftt,
round,
keysi = 0;
leftt = inInts[0];
right = inInts[1];
work = ((leftt >>> 4) ^ right) & 0x0f0f0f0f; work = ((leftt >>> 4) ^ right) & 0x0f0f0f0f;
right ^= work; right ^= work;
@ -359,24 +304,24 @@ var DES = {
for (round = 0; round < 8; ++round) { for (round = 0; round < 8; ++round) {
work = (right << 28) | (right >>> 4); work = (right << 28) | (right >>> 4);
work ^= keys[keysi++]; work ^= DES.keys[keysi++];
fval = DES.SP7[work & 0x0000003f]; fval = DES.SP7[work & 0x0000003f];
fval |= DES.SP5[(work >>> 8) & 0x0000003f]; fval |= DES.SP5[(work >>> 8) & 0x0000003f];
fval |= DES.SP3[(work >>> 16) & 0x0000003f]; fval |= DES.SP3[(work >>> 16) & 0x0000003f];
fval |= DES.SP1[(work >>> 24) & 0x0000003f]; fval |= DES.SP1[(work >>> 24) & 0x0000003f];
work = right ^ keys[keysi++]; work = right ^ DES.keys[keysi++];
fval |= DES.SP8[work & 0x0000003f]; fval |= DES.SP8[work & 0x0000003f];
fval |= DES.SP6[(work >>> 8) & 0x0000003f]; fval |= DES.SP6[(work >>> 8) & 0x0000003f];
fval |= DES.SP4[(work >>> 16) & 0x0000003f]; fval |= DES.SP4[(work >>> 16) & 0x0000003f];
fval |= DES.SP2[(work >>> 24) & 0x0000003f]; fval |= DES.SP2[(work >>> 24) & 0x0000003f];
leftt ^= fval; leftt ^= fval;
work = (leftt << 28) | (leftt >>> 4); work = (leftt << 28) | (leftt >>> 4);
work ^= keys[keysi++]; work ^= DES.keys[keysi++];
fval = DES.SP7[work & 0x0000003f]; fval = DES.SP7[work & 0x0000003f];
fval |= DES.SP5[(work >>> 8) & 0x0000003f]; fval |= DES.SP5[(work >>> 8) & 0x0000003f];
fval |= DES.SP3[(work >>> 16) & 0x0000003f]; fval |= DES.SP3[(work >>> 16) & 0x0000003f];
fval |= DES.SP1[(work >>> 24) & 0x0000003f]; fval |= DES.SP1[(work >>> 24) & 0x0000003f];
work = leftt ^ keys[keysi++]; work = leftt ^ DES.keys[keysi++];
fval |= DES.SP8[work & 0x0000003f]; fval |= DES.SP8[work & 0x0000003f];
fval |= DES.SP6[(work >>> 8) & 0x0000003f]; fval |= DES.SP6[(work >>> 8) & 0x0000003f];
fval |= DES.SP4[(work >>> 16) & 0x0000003f]; fval |= DES.SP4[(work >>> 16) & 0x0000003f];
@ -403,38 +348,21 @@ var DES = {
right ^= (work << 4); right ^= (work << 4);
outInts[0] = right; outInts[0] = right;
outInts[1] = leftt; outInts[1] = leftt;
},
// Routines taken from other parts of the Acme utilities. // Spread ints to bytes
o = offset;
// / Squash bytes down to ints. for (i = 0; i < 8; i++) {
squashBytesToInts: function (inBytes, inOff, outInts, outOff, intLen) { b[o+i] = (outInts[i>>>2] >>> (8*(3 - (i%4)))) % 256;
for (var i = 0; i < intLen; ++i) { if (b[o+i] < 0) { b[o+i] += 256; } // unsigned
outInts[outOff + i] = ((inBytes[inOff + i * 4] & 0xff) << 24)
| ((inBytes[inOff + i * 4+ 1] & 0xff) << 16)
| ((inBytes[inOff + i * 4+ 2] & 0xff) << 8)
| (inBytes[inOff + i * 4+ 3] & 0xff);
} }
}, },
// / Spread ints into unsigned bytes. // Encrypt 16 bytes of text using passwd as key
spreadIntsToBytes: function (inInts, inOff, outBytes, outOff, intLen) { encrypt: function(passwd, text) {
var i, j, idx; var i, cipher = text.slice();
for (i = 0; i < intLen; ++i) { DES.setKeys(passwd);
outBytes[outOff + i * 4] = (inInts[inOff + i] >>> 24) % 256; DES.encrypt8(cipher, 0);
outBytes[outOff + i * 4+ 1] = (inInts[inOff + i] >>> 16) % 256; DES.encrypt8(cipher, 8);
outBytes[outOff + i * 4+ 2] = (inInts[inOff + i] >>> 8) % 256; return cipher;
outBytes[outOff + i * 4+ 3] = (inInts[inOff + i]) % 256;
}
/* Make unsigned */
for (i = 0; i < intLen; ++i) {
for (j = 0; j < 4; j++) {
idx = outOff + i * 4 + j;
if (outBytes[idx] < 0) {
outBytes[idx] += 256;
}
}
}
} }
}; };

View File

@ -602,17 +602,11 @@ function send_string(str) {
} }
function genDES(password, challenge) { function genDES(password, challenge) {
var i, passwd, response; var i, passwd = [];
passwd = [];
response = challenge.slice();
for (i=0; i < password.length; i += 1) { for (i=0; i < password.length; i += 1) {
passwd.push(password.charCodeAt(i)); passwd.push(password.charCodeAt(i));
} }
return DES.encrypt(passwd, challenge);
DES.setKeys(passwd);
DES.encrypt(response, 0, response, 0);
DES.encrypt(response, 8, response, 8);
return response;
} }
function flushClient() { function flushClient() {