/* subprocs.c --- choosing, spawning, and killing screenhacks.
* xscreensaver, Copyright (c) 1991, 1992, 1993, 1995, 1997, 1998
- * Jamie Zawinski <jwz@netscape.com>
+ * Jamie Zawinski <jwz@jwz.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
#include <signal.h> /* for the signal names */
-#ifndef NO_SETUID
-#include <pwd.h> /* for getpwnam() and struct passwd */
-#include <grp.h> /* for getgrgid() and struct group */
-#endif /* NO_SETUID */
-
#if !defined(SIGCHLD) && defined(SIGCLD)
#define SIGCHLD SIGCLD
#endif
Bool hairy_p = !!strpbrk (command, "*?$&!<>[];`'\\\"");
if (p->verbose_p)
- printf ("%s: spawning \"%s\" in pid %lu%s.\n",
- blurb(), command, (unsigned long) getpid (),
- (hairy_p ? " (via shell)" : ""));
+ fprintf (stderr, "%s: spawning \"%s\" in pid %lu%s.\n",
+ blurb(), command, (unsigned long) getpid (),
+ (hairy_p ? " (via shell)" : ""));
if (hairy_p)
/* If it contains any shell metacharacters, do it the hard way,
#else /* VMS */
if (p->verbose_p)
- printf ("%s: spawning \"%s\" in pid %lu.\n", blurb(), command, getpid());
+ fprintf (stderr, "%s: spawning \"%s\" in pid %lu.\n",
+ blurb(), command, getpid());
exec_vms_command (command);
#endif /* VMS */
"%s: child pid %lu (%s) exited abnormally (code %d).\n",
blurb(), (unsigned long) kid, name, exit_status);
else if (p->verbose_p)
- printf ("%s: child pid %lu (%s) exited normally.\n",
- blurb(), (unsigned long) kid, name);
+ fprintf (stderr, "%s: child pid %lu (%s) exited normally.\n",
+ blurb(), (unsigned long) kid, name);
if (job)
job->status = job_dead;
sprintf (buf, "%s: couldn't fork", blurb());
perror (buf);
restore_real_vroot (si);
- saver_exit (si, 1);
+ saver_exit (si, 1, 0);
case 0:
close (ConnectionNumber (si->dpy)); /* close display fd */
if (!monitor_powered_on_p (si))
{
if (si->prefs.verbose_p)
- printf ("%s: server reports that monitor has powered down; "
- "not launching a new hack.\n", blurb());
+ fprintf (stderr,
+ "%s: server reports that monitor has powered down; "
+ "not launching a new hack.\n", blurb());
return;
}
}
#endif /* HAVE_PUTENV && DEFAULT_PATH_PREFIX */
}
-
-
-\f
-/* Change the uid/gid of the screensaver process, so that it is safe for it
- to run setuid root (which it needs to do on some systems to read the
- encrypted passwords from the passwd file.)
-
- hack_uid() is run before opening the X connection, so that XAuth works.
- hack_uid_warn() is called after the connection is opened and the command
- line arguments are parsed, so that the messages from hack_uid() get
- printed after we know whether we're in `verbose' mode.
- */
-
-#ifndef NO_SETUID
-
-static int hack_uid_errno;
-static char hack_uid_buf [255], *hack_uid_error;
-
-void
-hack_uid (saver_info *si)
-{
-
- /* If we've been run as setuid or setgid to someone else (most likely root)
- turn off the extra permissions so that random user-specified programs
- don't get special privileges. (On some systems it might be necessary
- to install this as setuid root in order to read the passwd file to
- implement lock-mode...)
- */
- setgid (getgid ());
- setuid (getuid ());
-
- hack_uid_errno = 0;
- hack_uid_error = 0;
-
- /* If we're being run as root (as from xdm) then switch the user id
- to something safe. */
- if (getuid () == 0)
- {
- struct passwd *p;
- /* Locking can't work when running as root, because we have no way of
- knowing what the user id of the logged in user is (so we don't know
- whose password to prompt for.)
- */
- si->locking_disabled_p = True;
- si->nolock_reason = "running as root";
- p = getpwnam ("nobody");
- if (! p) p = getpwnam ("noaccess");
- if (! p) p = getpwnam ("daemon");
- if (! p) p = getpwnam ("bin");
- if (! p) p = getpwnam ("sys");
- if (! p)
- {
- hack_uid_error = "couldn't find safe uid; running as root.";
- hack_uid_errno = -1;
- }
- else
- {
- struct group *g = getgrgid (p->pw_gid);
- hack_uid_error = hack_uid_buf;
- sprintf (hack_uid_error, "changing uid/gid to %s/%s (%ld/%ld).",
- p->pw_name, (g ? g->gr_name : "???"),
- (long) p->pw_uid, (long) p->pw_gid);
-
- /* Change the gid to be a safe one. If we can't do that, then
- print a warning. We change the gid before the uid so that we
- change the gid while still root. */
- if (setgid (p->pw_gid) != 0)
- {
- hack_uid_errno = errno;
- sprintf (hack_uid_error, "couldn't set gid to %s (%ld)",
- (g ? g->gr_name : "???"), (long) p->pw_gid);
- }
-
- /* Now change the uid to be a safe one. */
- if (setuid (p->pw_uid) != 0)
- {
- hack_uid_errno = errno;
- sprintf (hack_uid_error, "couldn't set uid to %s (%ld)",
- p->pw_name, (long) p->pw_uid);
- }
- }
- }
-# ifndef NO_LOCKING
- else /* disable locking if already being run as "someone else" */
- {
- struct passwd *p = getpwuid (getuid ());
- if (!p ||
- !strcmp (p->pw_name, "root") ||
- !strcmp (p->pw_name, "nobody") ||
- !strcmp (p->pw_name, "noaccess") ||
- !strcmp (p->pw_name, "daemon") ||
- !strcmp (p->pw_name, "bin") ||
- !strcmp (p->pw_name, "sys"))
- {
- si->locking_disabled_p = True;
- si->nolock_reason = hack_uid_buf;
- sprintf (si->nolock_reason, "running as %s", p->pw_name);
- }
- }
-# endif /* !NO_LOCKING */
-}
-
-void
-hack_uid_warn (saver_info *si)
-{
- saver_preferences *p = &si->prefs;
-
- if (! hack_uid_error)
- ;
- else if (hack_uid_errno == 0)
- {
- if (p->verbose_p)
- printf ("%s: %s\n", blurb(), hack_uid_error);
- }
- else
- {
- char buf [255];
- sprintf (buf, "%s: %s", blurb(), hack_uid_error);
- if (hack_uid_errno == -1)
- fprintf (stderr, "%s\n", buf);
- else
- {
- errno = hack_uid_errno;
- perror (buf);
- }
- }
-}
-
-#endif /* !NO_SETUID */
projects / xscreensaver / blobdiff