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/* $Id$ */
/* Copyright (C) 1998-99 Martin Baulig
This file is part of LibGTop 1.0.
Contributed by Martin Baulig <martin@home-of-linux.org>, April 1998.
LibGTop is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.
LibGTop is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with LibGTop; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
#include <glibtop.h>
#include <glibtop/open.h>
#include <glibtop/init_hooks.h>
#include <glibtop/error.h>
#include <glibtop_suid.h>
#include <unistd.h>
#include <sys/types.h>
/* !!! THIS FUNCTION RUNS SUID ROOT - CHANGE WITH CAUTION !!! */
void
glibtop_init_p (glibtop *server, const unsigned long features,
const unsigned flags)
{
const glibtop_init_func_t *init_fkt;
if (server == NULL)
glibtop_error_r (NULL, "glibtop_init_p (server == NULL)");
/* Do the initialization, but only if not already initialized. */
if ((server->flags & _GLIBTOP_INIT_STATE_INIT) == 0) {
glibtop_open_p (server, "glibtop", features, flags);
for (init_fkt = _glibtop_init_hook_p; *init_fkt; init_fkt++)
(*init_fkt) (server);
server->flags |= _GLIBTOP_INIT_STATE_INIT;
}
}
/* !!! THIS FUNCTION RUNS SUID ROOT - CHANGE WITH CAUTION !!! */
void
glibtop_open_p (glibtop *server, const char *program_name,
const unsigned long features, const unsigned flags)
{
/* !!! WE ARE ROOT HERE - CHANGE WITH CAUTION !!! */
server->name = program_name;
server->machine.uid = getuid ();
server->machine.euid = geteuid ();
server->machine.gid = getgid ();
server->machine.egid = getegid ();
server->machine.kd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL);
if(!server->machine.kd)
glibtop_warn_io_r(server, "kvm_open()");
/* Drop priviledges; we only become root when necessary.
setreuid (ruid, euid) - set real and effective user id;
setregid (rgid, egid) - set real and effective group id;
*/
if (setreuid (server->machine.euid, server->machine.uid))
_exit (1);
if (setregid (server->machine.egid, server->machine.gid))
_exit (1);
/* !!! END OF SUID ROOT PART !!! */
/* Our effective uid is now those of the user invoking the server,
so we do no longer have any priviledges.
*/
}
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