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Windows Script Decoder 1.8 (Decoding JScript.Encoded)
/**********************************************************************/
/* scrdec.c - Decoder for Microsoft Script Encoder */
/* Version 1.8 */
/* */
/* COPYRIGHT: */
/* (c)2000-2005 MrBrownstone, mrbrownstone@ virtualconspiracy.com */
/* v1.8 Now correctly decodes characters 0x00-0x1F, thanks to 'Zed' */
/* v1.7 Bypassed new HTMLGuardian protection and added -dumb switch */
/* to disable this */
/* v1.6 Added HTML Decode option (-htmldec) */
/* v1.5 Bypassed a cleaver trick defeating this tool */
/* v1.4 Some changes by Joe Steele to correct minor stuff */
/* */
/* DISCLAIMER: */
/* This program is for demonstrative and educational purposes only. */
/* Use of this program is at your own risk. The author cannot be held */
/* responsible if any laws are broken by use of this program. */
/* */
/* If you use or distribute this code, this message should be held */
/* intact. Also, any program based upon this code should display the */
/* copyright message and the disclaimer. */
/**********************************************************************/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define LEN_OUTBUF 64
#define LEN_INBUF 1024
#define STATE_INIT_COPY 100
#define STATE_COPY_INPUT 101
#define STATE_SKIP_ML 102
#define STATE_CHECKSUM 103
#define STATE_READLEN 104
#define STATE_DECODE 105
#define STATE_UNESCAPE 106
#define STATE_FLUSHING 107
#define STATE_DBCS 108
#define STATE_INIT_READLEN 109
#define STATE_URLENCODE_1 110
#define STATE_URLENCODE_2 111
#define STATE_WAIT_FOR_CLOSE 112
#define STATE_WAIT_FOR_OPEN 113
#define STATE_HTMLENCODE 114
unsigned char rawData[292] = {
0x64,0x37,0x69, 0x50,0x7E,0x2C, 0x22,0x5A,0x65, 0x4A,0x45,0x72,
0x61,0x3A,0x5B, 0x5E,0x79,0x66, 0x5D,0x59,0x75, 0x5B,0x27,0x4C,
0x42,0x76,0x45, 0x60,0x63,0x76, 0x23,0x62,0x2A, 0x65,0x4D,0x43,
0x5F,0x51,0x33, 0x7E,0x53,0x42, 0x4F,0x52,0x20, 0x52,0x20,0x63,
0x7A,0x26,0x4A, 0x21,0x54,0x5A, 0x46,0x71,0x38, 0x20,0x2B,0x79,
0x26,0x66,0x32, 0x63,0x2A,0x57, 0x2A,0x58,0x6C, 0x76,0x7F,0x2B,
0x47,0x7B,0x46, 0x25,0x30,0x52, 0x2C,0x31,0x4F, 0x29,0x6C,0x3D,
0x69,0x49,0x70, 0x3F,0x3F,0x3F, 0x27,0x78,0x7B, 0x3F,0x3F,0x3F,
0x67,0x5F,0x51, 0x3F,0x3F,0x3F, 0x62,0x29,0x7A, 0x41,0x24,0x7E,
0x5A,0x2F,0x3B, 0x66,0x39,0x47, 0x32,0x33,0x41, 0x73,0x6F,0x77,
0x4D,0x21,0x56, 0x43,0x75,0x5F, 0x71,0x28,0x26, 0x39,0x42,0x78,
0x7C,0x46,0x6E, 0x53,0x4A,0x64, 0x48,0x5C,0x74, 0x31,0x48,0x67,
0x72,0x36,0x7D, 0x6E,0x4B,0x68, 0x70,0x7D,0x35, 0x49,0x5D,0x22,
0x3F,0x6A,0x55, 0x4B,0x50,0x3A, 0x6A,0x69,0x60, 0x2E,0x23,0x6A,
0x7F,0x09,0x71, 0x28,0x70,0x6F, 0x35,0x65,0x49, 0x7D,0x74,0x5C,
0x24,0x2C,0x5D, 0x2D,0x77,0x27, 0x54,0x44,0x59, 0x37,0x3F,0x25,
0x7B,0x6D,0x7C, 0x3D,0x7C,0x23, 0x6C,0x43,0x6D, 0x34,0x38,0x28,
0x6D,0x5E,0x31, 0x4E,0x5B,0x39, 0x2B,0x6E,0x7F, 0x30,0x57,0x36,
0x6F,0x4C,0x54, 0x74,0x34,0x34, 0x6B,0x72,0x62, 0x4C,0x25,0x4E,
0x33,0x56,0x30, 0x56,0x73,0x5E, 0x3A,0x68,0x73, 0x78,0x55,0x09,
0x57,0x47,0x4B, 0x77,0x32,0x61, 0x3B,0x35,0x24, 0x44,0x2E,0x4D,
0x2F,0x64,0x6B, 0x59,0x4F,0x44, 0x45,0x3B,0x21, 0x5C,0x2D,0x37,
0x68,0x41,0x53, 0x36,0x61,0x58, 0x58,0x7A,0x48, 0x79,0x22,0x2E,
0x09,0x60,0x50, 0x75,0x6B,0x2D, 0x38,0x4E,0x29, 0x55,0x3D,0x3F,
0x51,0x67,0x2f
} ;
const unsigned char pick_encoding[64] = {
1, 2, 0, 1, 2, 0, 2, 0, 0, 2, 0, 2, 1, 0, 2, 0,
1, 0, 2, 0, 1, 1, 2, 0, 0, 2, 1, 0, 2, 0, 0, 2,
1, 1, 0, 2, 0, 2, 0, 1, 0, 1, 1, 2, 0, 1, 0, 2,
1, 0, 2, 0, 1, 1, 2, 0, 0, 1, 1, 2, 0, 1, 0, 2
};
unsigned char transformed[3][127];
int digits[0x7a];
int urlencoded = 0;
int htmlencoded = 0;
int verbose = 0;
int smart = 1;
unsigned char unescape (unsigned char c)
{
static unsigned char escapes[] = "#&!*$";
static unsigned char escaped[] = "\r\n<>@";
int i=0;
if (c > 127)
return c;
while (escapes[i])
{
if (escapes[i] == c)
return escaped[i];
i++;
}
return '?';
}
void maketrans (void)
{
int i, j;
for (i=0; i<32; i++)
for (j=0; j<3; j++)
transformed[j][i] = i;
for (i=31; i<=127; i++)
for (j=0; j<3; j++)
transformed[j][rawData[(i-31)*3 + j]] = (i==31) ? 9 : i;
}
void makedigits (void)
{
int i;
for (i=0; i<26; i++)
{
digits['A'+i] = i;
digits['a'+i] = i+26;
}
for (i=0; i<10; i++)
digits['0'+i] = i+52;
digits[0x2b] = 62;
digits[0x2f] = 63;
}
unsigned long int decodeBase64 (unsigned char *p)
{
unsigned long int val = 0;
val += (digits[p[0]] << 2);
val += (digits[p[1]] >> 4);
val += (digits[p[1]] & 0xf) << 12;
val += ((digits[p[2]] >> 2) << 8);
val += ((digits[p[2]] & 0x3) << 22);
val += (digits[p[3]] << 16);
val += ((digits[p[4]] << 2) << 24);
val += ((digits[p[5]] >> 4) << 24);
/* 543210 543210 543210 543210 543210 543210
765432
10
ba98
fedc
76
543210
fedcba 98----
|- LSB -||- -||- -| |- MSB -|
*/
return val;
}
/*
Char. number range | UTF-8 octet sequence
(hexadecimal) | (binary)
--------------------+---------------------------------------------
0000 0000-0000 007F | 0xxxxxxx
0000 0080-0000 07FF | 110xxxxx 10xxxxxx
0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
*/
int isLeadByte (unsigned int cp, unsigned char ucByte)
{
/* Code page 932 - Japanese Shift-JIS - 0x81-0x9f
0xe0-0xfc
936 - Simplified Chinese GBK - 0xa1-0xfe
949 - Korean Wansung - 0x81-0xfe
950 - Traditional Chinese Big5 - 0x81-0xfe
1361 - Korean Johab - 0x84-0xd3
0xd9-0xde
0xe0-0xf9 */
switch (cp)
{
case 932:
if ((ucByte > 0x80) && (ucByte < 0xa0)) return 1;
if ((ucByte > 0xdf) && (ucByte < 0xfd)) return 1;
else return 0;
case 936:
if ((ucByte > 0xa0) && (ucByte < 0xff)) return 1;
else return 0;
case 949:
case 950:
if ((ucByte > 0x80) && (ucByte < 0xff)) return 1;
else return 0;
case 1361:
if ((ucByte > 0x83) && (ucByte < 0xd4)) return 1;
if ((ucByte > 0xd8) && (ucByte < 0xdf)) return 1;
if ((ucByte > 0xdf) && (ucByte < 0xfa)) return 1;
else return 0;
default:
return 0;
}
}
struct entitymap {
char *entity;
char mappedchar;
};
struct entitymap entities[] = {
{"excl",33},{"quot",34},{"num",35},{"dollar",36},{"percent",37},
{"amp",38},{"apos",39},{"lpar",40},{"rpar",41},{"ast",42},
{"plus",43},{"comma",44},{"period",46},{"colon",58},{"semi",59},
{"lt",60},{"equals",61},{"gt",62},{"quest",63},{"commat",64},
{"lsqb",91},{"rsqb",93},{"lowbar",95},{"lcub",123},{"verbar",124},
{"rcub",125},{"tilde",126}, {NULL, 0}
};
char decodeMnemonic ( unsigned char *mnemonic)
{
int i=0;
while (entities[i].entity != NULL)
{
if (strcmp(entities[i].entity, mnemonic)==0)
return entities[i].mappedchar;
i++;
}
printf ("Warning: did not recognize HTML entity '%s'\n", mnemonic);
return '?';
}
int ScriptDecoder (unsigned char *inname, unsigned char *outname, unsigned int cp)
{
unsigned char inbuf[LEN_INBUF+1];
unsigned char outbuf[LEN_OUTBUF+1];
unsigned char c, c1, c2, lenbuf[7], csbuf[7], htmldec[8];
unsigned char marker[] = "#@~^";
int ustate, nextstate, state = 0;
int i, j, k, m, ml, hd = 0;
int utf8 = 0;
unsigned long int csum = 0, len = 0;
FILE *infile, *outfile;
infile = fopen ((const char*)inname, "rb");
outfile = fopen ((const char*)outname, "wb");
if (!infile || !outfile)
{
printf ("Error opening file!\n");
return 10;
}
maketrans();
makedigits();
memset (inbuf, 0, sizeof (inbuf));
memset (outbuf, 0, sizeof (outbuf));
memset (lenbuf, 0, sizeof (lenbuf));
state = STATE_INIT_COPY;
i = 0;
j = 0;
while (state)
{
if (inbuf[i] == 0)
{
if (feof (infile))
{
if (len)
{
printf ("Error: Premature end of file.\n");
if (utf8>0)
printf ("Tip: The file seems to contain special characters, try the -cp option.\n");
}
break;
}
memset (inbuf, 0, sizeof (inbuf));
fgets ((char*)inbuf, LEN_INBUF, infile);
i = 0;
continue;
}
if (j == LEN_OUTBUF)
{
fwrite (outbuf, sizeof(char), j, outfile);
j = 0;
}
if ((urlencoded==1) && (inbuf[i]=='%'))
{
ustate = state; /* save state */
state = STATE_URLENCODE_1; /* enter decoding state */
i++; /* flush char */
continue;
}
/* 2 means we do urldecoding but wanted to avoid decoding an
already decoded % for the second time */
if (urlencoded==2)
urlencoded=1;
if ((htmlencoded==1) && (inbuf[i]=='&'))
{
ustate = state;
state = STATE_HTMLENCODE;
hd = 0;
i++;
continue;
}
/* 2 means we do htmldecoding but wanted to avoid decoding an
already decoded & for the second time */
if (htmlencoded==2)
htmlencoded=1;
switch (state)
{
case STATE_INIT_COPY:
ml = strlen ((const char*)marker);
m = 0;
state = STATE_COPY_INPUT;
break;
/* after decoding a block, we have to wait for the current
script block to be closed (>) */
case STATE_WAIT_FOR_CLOSE:
if (inbuf[i] == '>')
state = STATE_WAIT_FOR_OPEN;
outbuf[j++] = inbuf[i++];
break;
/* and a new block to be opened again (<) */
case STATE_WAIT_FOR_OPEN:
if (inbuf[i] == '<')
state = STATE_INIT_COPY;
outbuf[j++] = inbuf[i++];
break;
case STATE_COPY_INPUT:
if (inbuf[i] == marker[m])
{
i++;
m++;
}
else
{
if (m)
{
k = 0;
state = STATE_FLUSHING;
}
else
outbuf[j++] = inbuf[i++];
}
if (m == ml)
state = STATE_INIT_READLEN;
break;
case STATE_FLUSHING:
outbuf[j++] = marker[k++];
m--;
if (m==0)
state = STATE_COPY_INPUT;
break;
case STATE_SKIP_ML:
i++;
if (!(--ml))
state = nextstate;
break;
case STATE_INIT_READLEN:
ml = 6;
state = STATE_READLEN;
break;
case STATE_READLEN:
lenbuf[6-ml] = inbuf[i++];
if (!(--ml))
{
len = decodeBase64 (lenbuf);
if (verbose)
printf ("Msg: Found encoded block containing %d characters.\n", len);
m = 0;
ml = 2;
state = STATE_SKIP_ML;
nextstate = STATE_DECODE;
}
break;
case STATE_DECODE:
if (!len)
{
ml = 6;
state = STATE_CHECKSUM;
break;
}
if (inbuf[i] == '@')
state = STATE_UNESCAPE;
else
{
if ((inbuf[i] & 0x80) == 0)
{
outbuf[j++] = c = transformed[pick_encoding[m%64]][inbuf[i]];
csum += c;
m++;
}
else
{
if (!cp && (inbuf[i] & 0xc0)== 0x80)
{
// utf-8 but not a start byte
len++;
utf8=1;
}
outbuf[j++] = inbuf[i];
if ((cp) && (isLeadByte (cp,inbuf[i])))
state = STATE_DBCS;
}
}
i++;
len--;
break;
case STATE_DBCS:
outbuf[j++] = inbuf[i++];
state = STATE_DECODE;
break;
case STATE_UNESCAPE:
outbuf[j++] = c = unescape (inbuf[i++]);
csum += c;
len--;
m++;
state = STATE_DECODE;
break;
case STATE_CHECKSUM:
csbuf[6-ml] = inbuf[i++];
if (!(--ml))
{
csum -= decodeBase64 (csbuf);
if (csum)
{
printf ("Error: Incorrect checksum! (%lu)\n", csum);
if (cp)
printf ("Tip: Maybe try another codepage.\n");
else
{
if (utf8>0)
printf ("Tip: The file seems to contain special characters, try the -cp option.\n");
else
printf ("Tip: the file may be corrupted.\n");
}
csum=0;
}
else
{
if (verbose)
printf ("Msg: Checksum OK\n");
}
m = 0;
ml = 6;
state = STATE_SKIP_ML;
if (smart)
nextstate = STATE_WAIT_FOR_CLOSE;
else
nextstate = STATE_INIT_COPY;
}
break;
/* urlencoded, the first character */
case STATE_URLENCODE_1:
c1 = inbuf[i++] - 0x30;
if (c1 > 0x9) c1-= 0x07;
if (c1 > 0x10) c1-= 0x20;
state = STATE_URLENCODE_2;
break;
/* urlencoded, second character */
case STATE_URLENCODE_2:
c2 = inbuf[i] - 0x30;
if (c2 > 0x9) c2-= 0x07;
if (c2 > 0x10) c2-= 0x20;
inbuf[i] = c2 + (c1<<4); /* copy decoded char back on input */
urlencoded=2; /* avoid looping in case this was an % */
state = ustate; /* restore old state */
break;
/* htmlencoded */
case STATE_HTMLENCODE:
c1 = inbuf[i];
if (c1 != ';')
{
i++;
htmldec[hd++] = c1;
if (hd>7)
{
htmldec[7]=0;
printf ("Error: HTML decode encountered a too long mnemonic (%s...)\n", htmldec);
exit(10);
}
}
else /* ';' = end of mnemonic */
{
htmldec[hd] = 0;
inbuf[i] = decodeMnemonic (htmldec); /* skip the & */
htmlencoded = 2; /* avoid looping in case of & */
state = ustate;
}
break;
default:
printf ("Internal Error: Invalid state: %d\n", state);
break;
}
}
fwrite (outbuf, sizeof (char), j, outfile);
fclose (infile);
fclose (outfile);
return 0;
}
int main (int argc, char **argv)
{
int i, cp = 0;
if (argc < 3)
{
puts ("ScrDec v1.8 - Decoder for Microsoft Script Encoder\n"
"(c)2000-2005 MrBrownstone, mrbrownstone@ virtualconspiracy.com\n"
"Home page: http://www.virtualconspiracy.com/scrdec.html\n\n"
"Usage: scrdec18 <infile> <outfile> [-cp codepage] [-urldec|-htmldec]\n"
" [-verbose] [-dumb]\n\n"
"Code pages can be 932 - Japanese\n"
" 936 - Chinese (Simplified)\n"
" 950 - Chinese (Traditional)\n"
" 949 - Korean (Wansung)\n"
" 1361 - Korean (Johab)\n"
"Any other code pages don't need to be specified.\n\n"
"Use -urldec to unescape %xx style encoding on the fly, or\n"
" -htmldec to unescape & style encoding.\n"
"For extra information, add the -verbose switch\n"
"You might not want to use the smart HTMLGuardian defeation mechanism.\n"
" In that case, add the -dumb switch.\n");
return 10;
}
i=3;
while (i<argc)
{
if (strcmp (argv[i], "-cp")==0)
{
i++;
if (i<argc) cp = atoi (argv[i]);
else
{
puts ("-cp should be followed by a code page identifier");
return 10;
}
}
else
if (strcmp (argv[i], "-urldec")==0)
urlencoded = 1;
else
if (strcmp (argv[i], "-htmldec")==0)
htmlencoded = 1;
else
if (strcmp (argv[i], "-verbose")==0)
verbose = 1;
else
if (strcmp (argv[i], "-dumb")==0)
smart = 0;
i++;
}
return ScriptDecoder ((unsigned char*)argv[1], (unsigned char*)argv[2], cp);
}

The Homepage of source code no longer alive: http://www.virtualconspiracy.com/scrdec.html
Thank's for republish stuff here.

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