# getcon

## 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 getpidprevcon(pid_t** _pid_**, char ****_context_**);**
    
           **int getpidprevcon_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**().
    
           **getpidprevcon**()
                  returns the process context before the last exec 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**(),
                  **getpidprevcon_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.
    
           Querying a foreign process via its PID, e.g. **getpidcon**() or
           **getpidprevcon**(), is inherently racy and therefore should never be
           relied upon for security purposes.
    


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