NAME

       getcon, getprevcon, getpidcon - get SELinux security context of a process

       freecon, freeconary - free memory associated with SELinux security contexts

       getpeercon - get security context of a peer socket

       setcon - set current security context of a process

SYNOPSIS

       #include <selinux/selinux.h>

       int getcon(char **context);

       int getcon_raw(char **context);

       int getprevcon(char **context);

       int getprevcon_raw(char **context);

       int getpidcon(pid_t pid, char **context);

       int getpidcon_raw(pid_t pid, char **context);

       int getpeercon(int fd, char **context);

       int getpeercon_raw(int fd, char **context);

       void freecon(char *con);

       void freeconary(char **con);

       int setcon(const char *context);

       int setcon_raw(const char *context);

DESCRIPTION

       getcon()
              retrieves the context of the current process, which must be free'd with freecon().

       getprevcon()
              same as getcon but gets the context before the last exec.

       getpidcon()
              returns  the  process  context  for  the  specified  PID, which must be free'd with
              freecon().

       getpeercon()
              retrieves the context of the peer socket, which must be free'd with freecon().

       freecon()
              frees the memory allocated for a security context.

              If con is NULL, no operation is performed.

       freeconary()
              frees the memory allocated for a context array.

              If con is NULL, no operation is performed.

       setcon()
              sets the current security context of the process to a new value.  Note that use  of
              this  function  requires  that  the  entire  application be trusted to maintain any
              desired separation between the old and new  security  contexts,  unlike  exec-based
              transitions performed via setexeccon(3).  When possible, decompose your application
              and use setexeccon(3) and execve(3) instead.

              Since access to file descriptors is  revalidated  upon  use  by  SELinux,  the  new
              context  must  be explicitly authorized in the policy to use the descriptors opened
              by the old context if that is desired.  Otherwise, attempts by the process  to  use
              any existing descriptors (including stdin, stdout, and stderr) after performing the
              setcon() will fail.

              A multi-threaded application can perform a setcon() prior  to  creating  any  child
              threads,  in  which  case  all  of  the child threads will inherit the new context.
              However, prior to Linux 2.6.28, setcon() would fail if there are any other  threads
              running  in  the  same  process  since  this would yield an inconsistency among the
              security contexts of threads sharing the same memory space.   Since  Linux  2.6.28,
              setcon()  is  permitted  for  threads  within  a  multi-threaded process if the new
              security context is bounded by the old security context, where the bounded relation
              is  defined through typebounds statements in the policy and guarantees that the new
              security context has a subset of the permissions of the old security context.

              If the process was being ptraced at the time  of  the  setcon()  operation,  ptrace
              permission  will  be revalidated against the new context and the setcon() will fail
              if it is not allowed by policy.

       *_raw()
              getcon_raw(), getprevcon_raw(), getpidcon_raw(), getpeercon_raw() and  setcon_raw()
              behave  identically  to  their  non-raw  counterparts  but  do  not perform context
              translation.

RETURN VALUE

       On error -1 is returned with errno set.  On success 0 is returned.

NOTES

       The retrieval functions might return success and set *context  to  NULL  if  and  only  if
       SELinux is not enabled.

SEE ALSO

       selinux(8), setexeccon(3)