From 12d2e7c192a63f90ad443ca1525083b72d4de74c Mon Sep 17 00:00:00 2001
From: Joel Martin <github@martintribe.org>
Date: Wed, 29 Sep 2010 14:48:19 -0500
Subject: [PATCH] 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.
---
include/des.js | 170 ++++++++++++++-----------------------------------
include/rfb.js | 10 +--
2 files changed, 51 insertions(+), 129 deletions(-)
diff --git a/include/des.js b/include/des.js
index ac56ea2..61163ed 100644
--- a/include/des.js
+++ b/include/des.js
@@ -83,34 +83,20 @@
var DES = {
// Tables, permutations, S-boxes, etc.
-
bytebit : [0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80],
bigbyte : [ 0x800000, 0x400000, 0x200000, 0x100000,
0x080000, 0x040000, 0x020000, 0x010000, 0x008000, 0x004000,
0x002000, 0x001000, 0x000800, 0x000400, 0x000200, 0x000100,
0x000080, 0x000040, 0x000020, 0x000010, 0x000008, 0x000004,
0x000002, 0x000001],
- pc1 : [ 56, 48, 40, 32,
- 24, 16, 8, 0, 57, 49,
- 41, 33, 25, 17, 9, 1,
- 58, 50, 42, 34, 26, 18,
- 10, 2, 59, 51, 43, 35,
- 62, 54, 46, 38, 30, 22,
- 14, 6, 61, 53, 45, 37,
- 29, 21, 13, 5, 60, 52,
- 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 ],
+ pc1 : [56,48,40,32,24,16, 8, 0,57,49,41,33,25,17, 9, 1,
+ 58,50,42,34,26,18,10, 2,59,51,43,35,62,54,46,38,
+ 30,22,14,6, 61,53,45,37,29,21,13, 5,60,52,44,36,
+ 28,20,12, 4,27,19,11, 3],
+ 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 ],
+ totrot : [ 1, 2, 4, 6, 8,10,12,14,15,17,19,21,23,25,27,28],
SP1 : [ 0x01010400, 0x00000000, 0x00010000,
0x01010404, 0x01010004, 0x00010404, 0x00000004, 0x00010000,
0x00000400, 0x01010400, 0x01010404, 0x00000400, 0x01000404,
@@ -224,26 +210,12 @@ var DES = {
0x00041000, 0x00001040, 0x00001040, 0x00040040, 0x10000000,
0x10041000],
- // Key routines.
-
- encryptKeys : [],
- decryptKeys : [],
+ keys : [],
- // / Set the key.
- 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);
+ // Set the key.
+ setKeys : function(keyBlock) {
+ var i, j, l, m, n, pc1m = [], pcr = [], kn = [],
+ raw0, raw1, rawi, KnLi;
for (j = 0; j < 56; ++j) {
l = DES.pc1[j];
@@ -252,11 +224,7 @@ var DES = {
}
for (i = 0; i < 16; ++i) {
- if (encrypting) {
- m = i << 1;
- } else {
- m = (15- i) << 1;
- }
+ m = i << 1;
n = m + 1;
kn[m] = kn[n] = 0;
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) {
- raw0 = raw[rawi++];
- raw1 = raw[rawi++];
- KnL[KnLi] = (raw0 & 0x00fc0000) << 6;
- KnL[KnLi] |= (raw0 & 0x00000fc0) << 10;
- KnL[KnLi] |= (raw1 & 0x00fc0000) >>> 10;
- KnL[KnLi] |= (raw1 & 0x00000fc0) >>> 6;
+ raw0 = kn[rawi++];
+ raw1 = kn[rawi++];
+ DES.keys[KnLi] = (raw0 & 0x00fc0000) << 6;
+ DES.keys[KnLi] |= (raw0 & 0x00000fc0) << 10;
+ DES.keys[KnLi] |= (raw1 & 0x00fc0000) >>> 10;
+ DES.keys[KnLi] |= (raw1 & 0x00000fc0) >>> 6;
++KnLi;
- KnL[KnLi] = (raw0 & 0x0003f000) << 12;
- KnL[KnLi] |= (raw0 & 0x0000003f) << 16;
- KnL[KnLi] |= (raw1 & 0x0003f000) >>> 4;
- KnL[KnLi] |= (raw1 & 0x0000003f);
+ DES.keys[KnLi] = (raw0 & 0x0003f000) << 12;
+ DES.keys[KnLi] |= (raw0 & 0x0000003f) << 16;
+ DES.keys[KnLi] |= (raw1 & 0x0003f000) >>> 4;
+ DES.keys[KnLi] |= (raw1 & 0x0000003f);
++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.
- encrypt: function(clearText, clearOff, cipherText, cipherOff) {
- var tempInts = new Array(12);
- DES.squashBytesToInts(clearText, clearOff, tempInts, 0, 2);
- 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];
+ // Squash 8 bytes down to 2 ints
+ o = offset;
+ leftt = b[o++]<<24 | b[o++]<<16 | b[o++]<<8 | b[o++];
+ right = b[o++]<<24 | b[o++]<<16 | b[o++]<<8 | b[o++];
work = ((leftt >>> 4) ^ right) & 0x0f0f0f0f;
right ^= work;
@@ -359,24 +304,24 @@ var DES = {
for (round = 0; round < 8; ++round) {
work = (right << 28) | (right >>> 4);
- work ^= keys[keysi++];
+ work ^= DES.keys[keysi++];
fval = DES.SP7[work & 0x0000003f];
fval |= DES.SP5[(work >>> 8) & 0x0000003f];
fval |= DES.SP3[(work >>> 16) & 0x0000003f];
fval |= DES.SP1[(work >>> 24) & 0x0000003f];
- work = right ^ keys[keysi++];
+ work = right ^ DES.keys[keysi++];
fval |= DES.SP8[work & 0x0000003f];
fval |= DES.SP6[(work >>> 8) & 0x0000003f];
fval |= DES.SP4[(work >>> 16) & 0x0000003f];
fval |= DES.SP2[(work >>> 24) & 0x0000003f];
leftt ^= fval;
work = (leftt << 28) | (leftt >>> 4);
- work ^= keys[keysi++];
+ work ^= DES.keys[keysi++];
fval = DES.SP7[work & 0x0000003f];
fval |= DES.SP5[(work >>> 8) & 0x0000003f];
fval |= DES.SP3[(work >>> 16) & 0x0000003f];
fval |= DES.SP1[(work >>> 24) & 0x0000003f];
- work = leftt ^ keys[keysi++];
+ work = leftt ^ DES.keys[keysi++];
fval |= DES.SP8[work & 0x0000003f];
fval |= DES.SP6[(work >>> 8) & 0x0000003f];
fval |= DES.SP4[(work >>> 16) & 0x0000003f];
@@ -403,38 +348,21 @@ var DES = {
right ^= (work << 4);
outInts[0] = right;
outInts[1] = leftt;
- },
- // Routines taken from other parts of the Acme utilities.
-
- // / Squash bytes down to ints.
- squashBytesToInts: function (inBytes, inOff, outInts, outOff, intLen) {
- for (var i = 0; i < intLen; ++i) {
- 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 to bytes
+ o = offset;
+ for (i = 0; i < 8; i++) {
+ b[o+i] = (outInts[i>>>2] >>> (8*(3 - (i%4)))) % 256;
+ if (b[o+i] < 0) { b[o+i] += 256; } // unsigned
}
},
- // / Spread ints into unsigned bytes.
- spreadIntsToBytes: function (inInts, inOff, outBytes, outOff, intLen) {
- var i, j, idx;
- for (i = 0; i < intLen; ++i) {
- outBytes[outOff + i * 4] = (inInts[inOff + i] >>> 24) % 256;
- outBytes[outOff + i * 4+ 1] = (inInts[inOff + i] >>> 16) % 256;
- outBytes[outOff + i * 4+ 2] = (inInts[inOff + i] >>> 8) % 256;
- 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;
- }
- }
- }
+ // Encrypt 16 bytes of text using passwd as key
+ encrypt: function(passwd, text) {
+ var i, cipher = text.slice();
+ DES.setKeys(passwd);
+ DES.encrypt8(cipher, 0);
+ DES.encrypt8(cipher, 8);
+ return cipher;
}
-
};
diff --git a/include/rfb.js b/include/rfb.js
index dd07389..ecd331b 100644
--- a/include/rfb.js
+++ b/include/rfb.js
@@ -602,17 +602,11 @@ function send_string(str) {
}
function genDES(password, challenge) {
- var i, passwd, response;
- passwd = [];
- response = challenge.slice();
+ var i, passwd = [];
for (i=0; i < password.length; i += 1) {
passwd.push(password.charCodeAt(i));
}
-
- DES.setKeys(passwd);
- DES.encrypt(response, 0, response, 0);
- DES.encrypt(response, 8, response, 8);
- return response;
+ return DES.encrypt(passwd, challenge);
}
function flushClient() {
--
2.18.1