ccsrch (c) 2007 Mike Beekey  - zaphod2718@yahoo.com All rights reserved

 Version 1.0.3

 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free
 Software Foundation; either version 2 of the License, or (at your option)
 any later version.

 This program is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 more details.

 You should have received a copy of the GNU General Public License along with
 this program; if not, write to the Free Software Foundation, Inc., 59
 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*******************************************************************************


This README describes the process for searching the filesystems for credit
card numbers.


ccsrch 1.0.3 (c) 2007 zaphod2718@yahoo.com
Usage: ./ccsrch <options> <start path>
  where <options> are:
    -b             Add the byte offset into the file of the number
    -e             Include the Modify Access and Create times in terms
                   of seconds since the epoch
    -f             Just output the filename with potential PAN data
    -j             Include the Modify Access and Create times in terms
                   of normal date/time
    -o <filename>  Output the data to the file <filename> vs. standard out
    -t <1 or 2>    Check if the pattern follows either a Track 1
                   or 2 format
    -T             Check for both Track 1 and Track 2 patterns
    -h             This stuff


Examples
---------------

# ccsrch ./ 		Generic search for credit card data starting in
			current directory with output to screen

# ccsrch -o mycard.log c:\storage	Generic search for credit card
					data starting in c:\storage with
					output to mycard.log

# ccsrch -t 2 ./ 	Search for credit card data and check for Track 2
			data formats with output to screen

# ccsrch -t 2 -o c.log ./ 	Search for credit card data and check for
				Track 2 data formats with output to file c.log


Output
---------------

All output is tab deliminated with the following order (depending on
the parameters):

Source File	Card Type	Card Number	Byte Offset	Modify Time	Access Time	Create Time	Track Pattern Match


Assumptions
---------------

The following assumptions are made throughout the program searching for the
card numbers:

1. Cards can be a minimum of 14 numbers and up to 16 numbers.
2. Card numbers must be contiguous.  The only characters ignored when
processing the files are carriage returns, new line feeds, and nulls.
3. Files are treated as raw binary objects and processed one character at
a time.
4. Solo and Switch cards are not processed in the prefix search.
5. Compressed or encoded files are NOT uncompressed or decoded in this version.
These files should be identified separately and the program run on the
decompressed or decoded versions.

Prefix Logic
The following prefixes are used to validate the potential card numbers that
have passed the mod 10 algorithm check.

Original Sources for Credit Card Prefixes
http://javascript.internet.com/forms/val-credit-card.html
http://www.erikandanna.com/Business/CreditCards/credit_card_authorization.htm

Logic Checks
---------------

Card Type: MasterCard
Valid Length: 16
Valid Prefixes: 51, 52, 53, 54, 55

Card Type: VISA
Valid Length: 16
Valid Prefix: 4

Card Type: Discover
Valid Length: 16
Valid Prefix: 6011

Card Type: JCB
Valid Length: 16
Valid Prefixes: 3088, 3096, 3112, 3158, 3337, 3528, 3529

Card Type: American Express
Valid Length: 15
Valid Prefixes: 34, 37

Card Type: EnRoute
Valid Length: 15
Valid Prefixes: 2014, 2149

Card Type: JCB
Valid Length: 15
Valid Prefixes: 1800, 2131, 3528, 3529

Card Type: Diners Club, Carte Blanche
Valid Length: 14
Valid Prefixes: 36, 300, 301, 302, 303, 304, 305, 380, 381, 382, 383, 384, 385, 386, 387, 388


Known Issues
---------------

One typical observation/complaint is the number of false positives that still
come up.  You will need to manually review and remove these. Certain patterns
will repeatedly come up which match all of the criteria for valid cards, but
are clearly bogus.  If there are enough cries for help, I may add some
additional sanity checks into the logic such as bank information. In addition,
there are certain system files which clearly should not have cardholder data
in them and can be ignored.  There may be an "ignore file list" in a new
release to reduce the amount of stuff to go through, however this will impact
the speed of the tool.

Note that since this program opens up each file and processes it, obviously
the access time (in epoch seconds) will change.  If you are going to do
forensics, one assumes that you have already collected an image following
standard forensic practices and either have already collected and preserved
the MAC times, or are using this tool on a copy of the image.

For the track data search feature, the tool just examines the preceding
characters before the valid credit card number and either the delimiter,
or the delimeter and the characters (e.g. expiration date) following the
credit card number.  This public release does not perform a full pattern
match using the Track 1 or Track 2 formats.

We have found that for some POS software log files are generated that not
only wrap across multiple lines, but insert hex representations of the
ASCII values of the PAN data as well. Furthermore, these log files may
contain track data. Remember that the only way that ccsrch will find the
PAN data and track data is if it is contiguous. In certain instances you
may luck out because the log files will contain an entire contigous PAN
and will get flagged. We would encourage you to visually examine the files
identified for confirmation. Introducing logic to capture all of the
crazy possible storage representations of PAN and track data we've seen
would make this tool a beast.

Please note that ccsrch recurses through the filesystem given a start
directory and will attempt to open any file or object read-only one at a time.
Given that this could be performance or load intensive depending on the
existing load on the system or its configuration, we recommend that you run
the tool on a subset or sample of directories first in order to get an idea
of the potential impact. We disclaim all liability for any performance impact,
outages, or problems ccsrch could cause.

Porting
---------------

This tool has been successfully compiled and run on the following operating
systems: FreeBSD, Linux, SCO 5.0.4-5.0.7, Solaris 8, AIX 4.1.X, Windows 2000,
and Windows XP.  If you have any issues getting it to run on any systems,
please contact the author.


Revisions
---------------
1.0.3	Added the ability to just output filenames of potential PAN data.
        Removed the 13 digit VISA  number check. Cleaned up some error and
        signal handling that varied across operating systems.

1.0.2	Added some additional track data format assumptions for track 1.

1.0.1	Added options for searching files for track data patterns.  Also
        added the ability to select certain output options on the
	command line.

0.9.3	Removed extraneous calls, simplified parameter passing, fixed
        non-portable type issues, removed debugging info

0.9.1	Initial release


Contributors
---------------
John A, Kyley S, Anand S, Chris L, Mitch A, Bill L, Phoram M


Last Update 29/08/07