Provided by: sleuthkit_4.6.5-1_amd64 bug

NAME

       sorter - Sort files in an image into categories based on file type

SYNOPSIS

       [-b  size  ]  [-e]  [-E] [-h] [-l] [-md5] [-s] [-sha1] [-U] [-v] [-V] [-a hash_alert ] [-c
       config ] [-C config ] [-d dir ] [-m mnt ] [-n nsrl_db ] [-x hash_exclude  ]  [-i  imgtype]
       [-o imgoffset] [-f fstype] image [image] [meta_addr]

DESCRIPTION

       sorter  is  a  Perl  script  that  analyzes  a  file  system to organize the allocated and
       unallocated files by file type.  It runs the 'file' command on each file and organizes the
       files  according  to the rules in configuration files.  Extension mismatching is also done
       to identify 'hidden' files.  One can also provide hash databases for files that are  known
       to be good and can be ignored and files that are known to be bad and should be alerted.

       By default, the program uses the configuration files in the directory where The Sleuth Kit
       was installed.   Those can be overruled  with  run-time  options.   There  is  a  standard
       configuration file for all file system types and then a specific one for a given operating
       system.

ARGUMENTS

       The required arguments are as follows.  This will analyze one or more  images  and  either
       save the results in the '-d' directory or list the results to STDOUT (if '-l' is given).

       -d dir Specify the location of where all files should be written.  This includes the index
              files and subdirectories if the '-s' flag is given.  This MUST be given, unless the
              '-l' list flag is given.

       -l     List  information  to  STDOUT  (no  files  are  ever  written).  This is useful for
              Incident Response, with the use of 'netcat'.  This cannot be used if '-d' is used.

       image [images]
              The disk or partition image to read, whose format is  given  with  '-i'.   Multiple
              image  file  names  can  be given if the image is split into multiple segments.  If
              only one image file is given, and its name is the first in  a  sequence  (e.g.,  as
              indicated  by  ending  in  '.001'),  subsequent  image  segments  will  be included
              automatically.

       The options are as follows:

       -f fstype
              Specify the file system type of the image(s).  This  is  the  same  type  that  The
              Sleuth Kit uses.

       -i imgtype
              Specify  the image type in which the file system is located.  This is the same type
              that The Sleuth Kit uses.

       -o imgoffset
              Specify the sector offset from the beginning of the image to the start of the  file
              system.

       -b size
              Specify the minimum size of file to process.  All files less than this size will be
              ignored.

       -c config
              Specify the location of an additional configuration file.  This file will be loaded
              in  addition  to  the  standard ones in the install directory.  These settings will
              have priority over the standard files.

       -C config
              Specify the location of the ONLY configuration file.   The  standard  config  files
              will  not  be  loaded  if  this  option is given.  For example, in the ´share/sort´
              directory there is a file called 'images.sort'.   This  file  contains  only  rules
              about  graphic  images.  If it is specified with -C, then only images will be saved
              about the image.

       -m mnt Specify the mounting point of the image being analyzed.  This is only for  cosmetic
              reasons.   When  the entries in the output files are written, the files will have a
              the full path instead of just the relative path.  If this is given, then  only  one
              image can be given.

       -a hash_alert
              Specify  the  location  a  hash database with entries of known 'bad' files.  If any
              file is found with an MD5 hash value in this database,  it  will  be  placed  in  a
              special  alert file.  This database must have been indexed for MD5 using 'hfind' in
              The Sleuth Kit before it is used by sorter.

       -n nsrl_db
              Specify the location  of  the  NIST  National  Software  Reference  Library  (NSRL)
              database  (www.nsrl.nist.org).   Any file found in the NSRL will be ignored and not
              placed into a category.  The database must be indexed for MD5 with 'hfind'  in  The
              Sleuth  Kit  before  it  is  used by sorter.  The database file is currently called
              'NSRLFile.txt'.

       -x hash_exclude
              Specify the location a hash database with entries of known 'good'  files.   If  any
              file  is  found with an MD5 hash value in this database, it will be ignored and not
              processed or saved to the category files.  This database must have been indexed for
              MD5 using 'hfind' in The Sleuth Kit before it is used by sorter.

       -e     Perform extension mismatch checks on (no category index files are generated)

       -U     Do no save data about unknown file types.  By default, an 'unknown' file is created
              for files where the 'file' output is not known.  This allows one  to  refine  their
              configuration.  If this is not desired, use this flag.

       -h     Create category files in HTML

       -md5   Calculate  the MD5 value for each file and save it in the category file.  This will
              be done automatically when any of the databases are given.

       -sha1  Calculate the SHA-1 value for each file and save it in the category file.

       -s     Save the actual file content to sub-directories in the directory specified by '-d'.
              For  example,  all  JPG  and  GIF  files  would  actually  be saved in the 'images'
              directory.  If '-h' is also given, thumbnails of graphic images are also created.

       -v     Display verbose information

       -V     Display version.

       [meta_addr]
              The meta data address of the  directory  to  start  with.   By  default,  the  root
              directory is used.  If this is given, then only one image can be given.

HIGH-LEVEL OVERVIEW OF PROCESS

       sorter  is  a  Perl  script  that interacts with other The Sleuth Kit tools.  It starts by
       reading the configuration files from the  installation  directory.   There  is  a  general
       configuration  file  and  a  specific  one for each operating system.  The specific one is
       determined from the '-f' flag.  Each configuration file contains rules for processing  the
       output  of the 'file' command.  One type of line identifies which category (i.e. 'images')
       a given 'file' output  belongs  to  (i.e.   ´image  data´)  (using  regular  expressions).
       Another  rule  shows  the file extensions (i.e. .txt) that belong to a 'file' output (i.e.
       ASCII(.*?)text).  See the Rules section below.

       The program then runs the 'fls' tool in The Sleuth Kit to identify the files in  the  file
       system  image.   Each identified file is viewed using the 'icat' tool.  If a hash database
       is given, the hash of the file is calculated and looked up.  If it is found in an  'alert'
       database,  then  it is added to a special 'alert.txt' file.  If it is found in the NSRL or
       'exclude' database, then it is ignored as a known good file.  Excluded files are  recorded
       in an 'exclude' file for future reference but it is not saved in the category files.

       The  'file'  command  is then run to identify the file type (based on header information).
       The configuration file rules are used to identify which category it belongs to.  An  entry
       is added to the corresponding category file (in the '-d dir' directory).  If the '-s' flag
       is given, then a copy of the file is saved in a subdirectory  of  the  same  name  as  the
       category.   If  the  HTML  format  is used, then hyper-links will allow one to easily view
       saved files and view what is in each category.

       Files that do not have a category are recorded in the 'unknown' category  and  the  'data'
       category.  'data' is for files with a structure that 'file' does not know and 'unknown' is
       for files with a structure that 'file' knows about.  These are saved for future reference,
       but the unknown category can be ignored by using the '-U' flag.

       A  copy of the files can be saved by using the '-s' flag.  If so, then the files are saved
       in a subdirectory that is named with the category name.  Each file is named using the file
       system  image name followed by the meta data address and the original file extension.  The
       category index file can be used to translate the actual name to the saved name.  The  HTML
       format makes viewing easier as there are links to each file from the category index file.

       The  program  will  also  consult  the rules about the file extension.  If the file has an
       extension at the end of it (anything after a ´.´), it will be compared to the  rules.   If
       the extension is not found in the rules as a valid extension for the file type, it will be
       added to the file of 'mismatch'.  If the file does not have an extension it  will  not  be
       entered  even  if the file type has valid extensions.  This check is done even if the file
       is found in one of the known good hash databases.  If it is found in one of those, it will
       be added to a special file.  Files of type 'data' have no extension checks done by default
       (as they have an unknown structure).

       The program repeats the above procedures using the output of the 'ils'  command  as  well.
       This allows 'sorter' to examine the contents of unallocated files that still have pointers
       to the data units (not all file systems will produce data from this step).

CONFIGURATION FILES

       Configuration files are used to define what file types belong in which categories and what
       extensions  belong  to  what  file  types.   Configuration  files are distributed with the
       'sorter' tool and  are  located  in  the  installation  directory  in  the  'share/sorter'
       directory.

       The  'default.sort'  file is used by any file system type.  It contains entries for common
       file types.  A specific operating system file also exists, which is useful for  extensions
       that  are  specific  to  a given OS.  By default, the default file and the OS specific one
       will be used.  Using the '-c' flag, an additional file can be used.  If the '-C'  flag  is
       used, then only the supplied configuration file is used.

       There  are two rule types in the configuration files.  Each rule starts with a header that
       specifies which rule type it is (category or ext).  Both rule types  have  two  additional
       columns that can be separated by any white space.

       The category rule has the category name as the second column and a Perl regular expression
       in the third column.  The category name can not have any spaces in  it  and  can  only  be
       letters and numbers.  The regular expression is used to examine the output of 'file'.  The
       regular expression will be used case insensitive.  More than one  rule  can  exist  for  a
       category, but only one category can exist for a given file output.  For example:

       This saves all file output with 'image data' anywhere in it to the ´images´ category:
           category        images          image data

       This  saves  all  file  output that has 'ASCII' followed by anything and then 'text' to be
       saved to the 'text' category:
           category        text            ASCII(.*?)text

       This saves all file output that is just 'data' to the 'data' category (the ^ and $  define
       the  boundaries  in  Perl).   The 'data' value is common in the output of file for unknown
       binary data.
           category        data            ^data?

       There is a special category of 'ignore' that is used to skip  over  files  of  this  type.
       This is mainly a time and space saver.

       The  extension  rule is similar except that the second column has the value extensions for
       the file output.  Multiple rules can exist for the same file type.  The comparison will be
       done  case  insensitive.  If no extension is valid for the file type, a rule does not need
       to be made.  That is already assumed.

       For example, the ASCII is used for several file extensions so the  following  rules  could
       exist:

           ext             txt,log         ASCII(.*?)text
           ext             c,cpp,h,js      ASCII(.*?)text

       Please  email  me  any  rules  that you find useful for standard investigations and I will
       incorporate them into future releases (carrier at sleuthkit dot org).

EXAMPLES

       To run sorter with no hash databases, the following can be used:

           # sorter -f ntfs -d data/sorter images/hda1.dd
           # sorter -d data/sorter images/hda1.dd

           # sorter -i raw -f ntfs -o 63 -d data/sorter images/hda.dd

       To include the NSRL, an exclude, and an alert hash database:

           # sorter -f ntfs -d data/sorter -a /usr/hash/rootkit.db         -x  /usr/hash/win2k.db
       -n /usr/hash/nsrl/NSRLFile.txt       images/hda1.dd

       To just identify images using the supplied 'images.sort' file:

           #  sorter -f ntfs -C /usr/local/sleuthkit/share/sort/images.sort     -d data/sorter -h
       -s images/hda1.dd

REQUIREMENTS

       The NIST National Software Reference Library (NSRL) can be found at www.nsrl.nist.gov.

LICENSE

       Distributed under the Common Public License, found in  the  cpl1.0.txt  file  in  the  The
       Sleuth Kit licenses directory.

AUTHOR

       Brian Carrier <carrier at sleuthkit dogt org>

       Send documentation updates to <doc-updates at sleuthkit dot org>

                                                                                        SORTER(1)