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)