From: Karel Zak <kzak@redhat.com>
Date: Thu, 12 Apr 2007 12:35:46 +0000 (+0200)
Subject: mount: add support for mtab "uhelper" option
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd9f213ab6efd352f67bc18071c16239d1002b94;p=util-linux

mount: add support for mtab "uhelper" option

The helper is an external /sbin/umount.<suffix> program where the
suffix is a value from the uhelper= option from /etc/mtab.

The uhelper (unprivileged umount helper) is possible to used when
non-root user wants to umount a mountpoint which is not defined in the
/etc/fstab file (e.g devices mounted by HAL).

This option is already supported by HAL upstream.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/mount/mount.c b/mount/mount.c
index 1360d235..7c1f1bdc 100644
--- a/mount/mount.c
+++ b/mount/mount.c
@@ -188,7 +188,7 @@ static const struct opt_map opt_map[] = {
 };
 
 static const char *opt_loopdev, *opt_vfstype, *opt_offset, *opt_encryption,
-	*opt_speed, *opt_comment;
+	*opt_speed, *opt_comment, *opt_uhelper;
 
 static struct string_opt_map {
   char *tag;
@@ -201,6 +201,7 @@ static struct string_opt_map {
   { "encryption=", 0, &opt_encryption },
   { "speed=", 0, &opt_speed },
   { "comment=", 1, &opt_comment },
+  { "uhelper=", 0, &opt_uhelper },
   { NULL, 0, NULL }
 };
 
diff --git a/mount/umount.8 b/mount/umount.8
index fafbff26..5d38ac8d 100644
--- a/mount/umount.8
+++ b/mount/umount.8
@@ -122,6 +122,19 @@ or when the \-d option was given.
 Any pending loop devices can be freed using `losetup -d', see
 .BR losetup (8).
 
+.SH NOTES
+The syntax of external umount helpers is:
+
+.br
+.BI "/sbin/umount.<suffix> [\-nlfvr] " "dir " | " device "
+.br
+
+where the <suffix> is filesystem type or a value from "uhelper=" mtab option.
+
+The uhelper (unprivileged umount helper) is possible to used when non-root user
+wants to umount a mountpoint which is not defined in the /etc/fstab file (e.g
+devices mounted by HAL).
+
 .SH FILES
 .I /etc/mtab
 table of mounted file systems
diff --git a/mount/umount.c b/mount/umount.c
index 676ed8cc..8a59f120 100644
--- a/mount/umount.c
+++ b/mount/umount.c
@@ -565,6 +565,23 @@ umount_file (char *arg) {
 			die(2,
 			    _("umount: %s is not mounted (according to mtab)"),
 			    file);
+		/*
+		 * uhelper - unprivileged umount helper
+		 * -- external umount (for example HAL mounts)
+		 */
+		if (external_allowed) {
+			char *uhelper = NULL;
+
+			if (mc->m.mnt_opts)
+				uhelper = get_value(mc->m.mnt_opts, "uhelper=");
+			if (uhelper) {
+				int status = 0;
+				if (check_special_umountprog(arg, arg,
+							uhelper, &status))
+					return status;
+			}
+		}
+
 		/* The 2.4 kernel will generally refuse to mount the same
 		   filesystem on the same mount point, but will accept NFS.
 		   So, unmounting must be possible. */