libselinux/man/man3/getexeccon.3

.TH "getexeccon" "3" "1 January 2004" "russell@coker.com.au" "SELinux API documentation"
.SH "NAME"
getexeccon, setexeccon \- get or set the SELinux security context used for executing a new process

rpm_execcon \- run a helper for rpm in an appropriate security context
.
.SH "SYNOPSIS"
.B #include <selinux/selinux.h>
.sp
.BI "int getexeccon(security_context_t *" context );
.sp
.BI "int setexeccon(security_context_t "context );
.sp
.BI "int rpm_execcon(unsigned int " verified ", const char *" filename ", char *const " argv "[] , char *const " envp "[]);
.
.SH "DESCRIPTION"
.BR getexeccon ()
retrieves the context used for executing a new process.
This returned context should be freed with
.BR freecon (3)
if non-NULL.
.BR getexeccon ()
sets
.BI * context
to NULL if no exec context has been explicitly
set by the program (i.e. using the default policy behavior).

.BR setexeccon ()
sets the context used for the next
.BR execve (2)
call.
NULL can be passed to
.BR setexeccon ()
to reset to the default policy behavior.
The exec context is automatically reset after the next
.BR execve (2),
so a program doesn't need to explicitly sanitize it upon startup.

.BR setexeccon ()
can be applied prior to library
functions that internally perform an
.BR execve (2),
e.g.
.BR execl *(3),
.BR execv *(3),
.BR popen (3),
in order to set an exec context for that operation.  

.B Note:
Signal handlers that perform an
.BR execve (2)
must take care to
save, reset, and restore the exec context to avoid unexpected behavior.

.BR rpm_execcon ()
runs a helper for rpm in an appropriate security context.  The
verified parameter should contain the return code from the signature
verification (0 == ok, 1 == notfound, 2 == verifyfail, 3 ==
nottrusted, 4 == nokey), although this information is not yet used by
the function.  The function determines the proper security context for
the helper based on policy, sets the exec context accordingly, and
then executes the specified filename with the provided argument and
environment arrays.
.
.SH "RETURN VALUE"
On error \-1 is returned.

On success
.BR getexeccon ()
and
.BR setexeccon ()
returns 0.
.BR rpm_execcon ()
only returns upon errors, as it calls
.BR execve (2).
.
.SH "SEE ALSO"
.BR selinux "(8), " freecon "(3), " getcon "(3)"