UBUNTU: SAUCE: apparmor: Add the ability to mediate mount

Add the ability for apparmor to do mediation of mount operations. Mount
rules require an updated apparmor_parser (2.8 series) for policy compilation.

The basic form of the rules are.

  [audit] [deny] mount [conds]* [device] [ -> [conds] path],
  [audit] [deny] remount [conds]* [path],
  [audit] [deny] umount [conds]* [path],
  [audit] [deny] pivotroot [oldroot=<value>] <path>

  remount is just a short cut for mount options=remount

  where [conds] can be
    fstype=<expr>
    options=<expr>

Example mount commands
  mount,		# allow all mounts, but not umount or pivotroot

  mount fstype=procfs,  # allow mounting procfs anywhere

  mount options=(bind, ro) /foo -> /bar,  # readonly bind mount

  mount /dev/sda -> /mnt,

  mount /dev/sd** -> /mnt/**,

  mount fstype=overlayfs options=(rw,upperdir=/tmp/upper/,lowerdir=/) -> /mnt/

  umount,

  umount /m*,

See the apparmor userspace for full documentation

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

1 files changed, 54 insertions, 0 deletions

diff --git a/security/apparmor/include/mount.h b/security/apparmor/include/mount.h
new file mode 100644
index 00000000000..bc17a5388ae
--- /dev/null
+++ b/security/apparmor/include/mount.h
@@ -0,0 +1,54 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor file mediation function definitions.
+ *
+ * Copyright 2012 Canonical Ltd.
+ *
+ * This program 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, version 2 of the
+ * License.
+ */
+
+#ifndef __AA_MOUNT_H
+#define __AA_MOUNT_H
+
+#include <linux/fs.h>
+#include <linux/path.h>
+
+#include "domain.h"
+#include "policy.h"
+
+/* mount perms */
+#define AA_MAY_PIVOTROOT	0x01
+#define AA_MAY_MOUNT		0x02
+#define AA_MAY_UMOUNT		0x04
+#define AA_AUDIT_DATA		0x40
+#define AA_CONT_MATCH		0x40
+
+#define AA_MS_IGNORE_MASK (MS_KERNMOUNT | MS_NOSEC | MS_ACTIVE | MS_BORN)
+
+int aa_remount(struct aa_profile *profile, struct path *path,
+	       unsigned long flags, void *data);
+
+int aa_bind_mount(struct aa_profile *profile, struct path *path,
+		  const char *old_name, unsigned long flags);
+
+
+int aa_mount_change_type(struct aa_profile *profile, struct path *path,
+			 unsigned long flags);
+
+int aa_move_mount(struct aa_profile *profile, struct path *path,
+		  const char *old_name);
+
+int aa_new_mount(struct aa_profile *profile, const char *dev_name,
+		 struct path *path, const char *type, unsigned long flags,
+		 void *data);
+
+int aa_umount(struct aa_profile *profile, struct vfsmount *mnt, int flags);
+
+int aa_pivotroot(struct aa_profile *profile, struct path *old_path,
+		  struct path *new_path);
+
+#endif /* __AA_MOUNT_H */