NAME

       captest - a program to demonstrate capabilities

SYNOPSIS

       captest [ --ambient --drop-all | --drop-caps | --id ] [ --init-grp ] [ --lock ] [ --text ]

DESCRIPTION

       captest  is  a  program  that  demonstrates  and prints out the current process capabilities. Each option
       prints the same report. It will output current capabilities. then  it  will  try  to  access  /etc/shadow
       directly  to  show if that can be done. Then it creates a child process that attempts to read /etc/shadow
       and outputs the results of that. Then it outputs the capabilities that a child process would have.

       You can also apply file system capabilities to this program to study how they work. For example,  filecap
       /usr/bin/captest  chown.  Then  run captest as a normal user. Another interesting test is to make captest
       suid root so that you can see what the interaction is between root's credentials  and  capabilities.  For
       example,  chmod  4755  /usr/bin/captest.  When  run  as  a normal user, the program will see if privilege
       escalation is possible. But do not leave this app setuid root after  you  are  don  testing  so  that  an
       attacker cannot take advantage of it.

OPTIONS

       --ambient
              This attempts to add CAP_CHOWN ambient capability.

       --drop-all
              This drops all capabilities including ambient and clears the bounding set.

       --drop-caps
              This drops just traditional capabilities.

       --id   This changes to uid and gid 99, drops supplemental groups, and clears the bounding set.

       --init-grp
              This changes to uid and gid 99 and then adds any supplemental groups that comes with that account.
              You would have add them prior to testing because by default there are no  supplemental  groups  on
              account 99.

       --text This option outputs the effective capabilities in text rather than numerically.

       --lock This prevents the ability for child processes to regain privileges if the uid is 0.

SEE ALSO

       filecap(8), capabilities(7)

AUTHOR

       Steve Grubb