platform_external_selinux/libselinux/man/man3/getexeccon.3
Stephen Smalley 9eb9c93275 Get rid of security_context_t and fix const declarations.
In attempting to enable building various part of Android with -Wall -Werror,
we found that the const security_context_t declarations in libselinux
are incorrect; const char * was intended, but const security_context_t
translates to char * const and triggers warnings on passing
const char * from the caller.   Easiest fix is to replace them all with
const char *.  And while we are at it, just get rid of all usage of
security_context_t itself as it adds no value - there is no true
encapsulation of the security context strings and callers already
directly use string functions on them.  typedef left to permit
building legacy users until such a time as all are updated.

This is a port of Change-Id I2f9df7bb9f575f76024c3e5f5b660345da2931a7
from Android, augmented to deal with all of the other code in upstream
libselinux and updating the man pages too.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
2014-02-19 16:11:48 -05:00

105 lines
2.9 KiB
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.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(char **" context );
.sp
.BI "int getexeccon_raw(char **" context );
.sp
.BI "int setexeccon(char * "context );
.sp
.BI "int setexeccon_raw(char * "context );
.sp
.BI "int setexecfilecon(const char *" filename ", const char *" fallback_type );
.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.
.BR getexeccon_raw ()
and
.BR setexeccon_raw ()
behave identically to their non-raw counterparts but do not perform context
translation.
.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 setexecfilecon ()
sets the context used for the next
.BR execve (2)
call, based on the policy for the
.IR filename ,
and falling back to a new context with a
.I fallback_type
in case there is no transition.
.BR rpm_execcon ()
is deprecated; please use
.BR setexecfilecon ()
in conjunction with
.BR execve (2)
in all new code. This function
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 (),
.BR setexeccon ()
and
.BR setexecfilecon ()
return 0.
.BR rpm_execcon ()
only returns upon errors, as it calls
.BR execve (2).
.
.SH "SEE ALSO"
.BR selinux "(8), " freecon "(3), " getcon "(3)"