[src/trunk]: src/sys Put the tty opening policy back in the subsystem.

[elad <elad%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f40ba1be04ef
branches:  trunk
changeset: 747835:f40ba1be04ef
user:      elad <elad%NetBSD.org@localhost>
date:      Fri Oct 02 23:58:53 2009 +0000

description:
Put the tty opening policy back in the subsystem.

Remove include we don't need from the secmodel code.

diffstat:

 sys/kern/tty.c                      |  39 +++++++++++++++++++++++++++++++++++-
 sys/secmodel/suser/secmodel_suser.c |  15 ++-----------
 2 files changed, 40 insertions(+), 14 deletions(-)

diffs (124 lines):

diff -r fbbeb089facb -r f40ba1be04ef sys/kern/tty.c
--- a/sys/kern/tty.c    Fri Oct 02 23:50:16 2009 +0000
+++ b/sys/kern/tty.c    Fri Oct 02 23:58:53 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tty.c,v 1.232 2009/08/01 23:07:05 christos Exp $       */
+/*     $NetBSD: tty.c,v 1.233 2009/10/02 23:58:53 elad Exp $   */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -63,7 +63,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: tty.c,v 1.232 2009/08/01 23:07:05 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: tty.c,v 1.233 2009/10/02 23:58:53 elad Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -206,6 +206,8 @@
 uint64_t tk_nout;
 uint64_t tk_rawcc;
 
+static kauth_listener_t tty_listener;
+
 SYSCTL_SETUP(sysctl_kern_tkstat_setup, "sysctl kern.tkstat subtree setup")
 {
 
@@ -2717,6 +2719,36 @@
        va_end(ap);
 }
 
+static int
+tty_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
+    void *arg0, void *arg1, void *arg2, void *arg3)
+{
+       struct tty *tty;
+       int result;
+
+       result = KAUTH_RESULT_DEFER;
+
+       if (action != KAUTH_DEVICE_TTY_OPEN)
+               return result;
+
+       tty = arg0;
+
+       /* If it's not opened, we allow. */
+       if ((tty->t_state & TS_ISOPEN) == 0)
+               result = KAUTH_RESULT_ALLOW;
+       else {
+               /*
+                * If it's opened, we can only allow if it's not exclusively
+                * opened; otherwise, that's a privileged operation and we
+                * let the secmodel handle it.
+                */
+               if ((tty->t_state & TS_XCLUDE) == 0)
+                       result = KAUTH_RESULT_ALLOW;
+       }
+
+       return result;
+}
+
 /*
  * Initialize the tty subsystem.
  */
@@ -2728,6 +2760,9 @@
        rw_init(&ttcompat_lock);
        tty_sigsih = softint_establish(SOFTINT_CLOCK, ttysigintr, NULL);
        KASSERT(tty_sigsih != NULL);
+
+       tty_listener = kauth_listen_scope(KAUTH_SCOPE_DEVICE,
+           tty_listener_cb, NULL);
 }
 
 /*
diff -r fbbeb089facb -r f40ba1be04ef sys/secmodel/suser/secmodel_suser.c
--- a/sys/secmodel/suser/secmodel_suser.c       Fri Oct 02 23:50:16 2009 +0000
+++ b/sys/secmodel/suser/secmodel_suser.c       Fri Oct 02 23:58:53 2009 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: secmodel_suser.c,v 1.13 2009/10/02 23:50:16 elad Exp $ */
+/* $NetBSD: secmodel_suser.c,v 1.14 2009/10/02 23:58:53 elad Exp $ */
 /*-
  * Copyright (c) 2006 Elad Efrat <elad%NetBSD.org@localhost>
  * All rights reserved.
@@ -38,7 +38,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: secmodel_suser.c,v 1.13 2009/10/02 23:50:16 elad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: secmodel_suser.c,v 1.14 2009/10/02 23:58:53 elad Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -48,7 +48,6 @@
 #include <sys/mount.h>
 #include <sys/socketvar.h>
 #include <sys/sysctl.h>
-#include <sys/tty.h>
 #include <sys/vnode.h>
 #include <sys/proc.h>
 #include <sys/uidinfo.h>
@@ -955,7 +954,6 @@
 secmodel_suser_device_cb(kauth_cred_t cred, kauth_action_t action,
     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
 {
-       struct tty *tty;
         bool isroot;
         int result;
 
@@ -1001,14 +999,7 @@
                break;
 
        case KAUTH_DEVICE_TTY_OPEN:
-               tty = arg0;
-
-               if (!(tty->t_state & TS_ISOPEN))
-                       result = KAUTH_RESULT_ALLOW;
-               else if (tty->t_state & TS_XCLUDE) {
-                       if (isroot)
-                               result = KAUTH_RESULT_ALLOW;
-               } else
+               if (isroot)
                        result = KAUTH_RESULT_ALLOW;
 
                break;