Added 'zero' command to wipe partition tables and superblocks.

25 files changed, 573 insertions, 5 deletions

diff --git a/daemon/Makefile.am b/daemon/Makefile.am
index 91237e23..c2c4a118 100644
--- a/daemon/Makefile.am
+++ b/daemon/Makefile.am
@@ -41,6 +41,7 @@ guestfsd_SOURCES = \
 	sync.c \
 	tar.c \
 	upload.c \
+	zero.c \
 	../src/guestfs_protocol.h \
 	../src/guestfs_protocol.c
 
diff --git a/daemon/actions.h b/daemon/actions.h
index 74555862..501e3377 100644
--- a/daemon/actions.h
+++ b/daemon/actions.h
@@ -105,3 +105,4 @@ extern char *do_get_e2label (const char *device);
 extern int do_set_e2uuid (const char *device, const char *uuid);
 extern char *do_get_e2uuid (const char *device);
 extern int do_fsck (const char *fstype, const char *device);
+extern int do_zero (const char *device);
diff --git a/daemon/stubs.c b/daemon/stubs.c
index 9e0ce559..937913f3 100644
--- a/daemon/stubs.c
+++ b/daemon/stubs.c
@@ -2103,6 +2103,30 @@ done:
   xdr_free ((xdrproc_t) xdr_guestfs_fsck_args, (char *) &args);
 }
 
+static void zero_stub (XDR *xdr_in)
+{
+  int r;
+  struct guestfs_zero_args args;
+  const char *device;
+
+  memset (&args, 0, sizeof args);
+
+  if (!xdr_guestfs_zero_args (xdr_in, &args)) {
+    reply_with_error ("%s: daemon failed to decode procedure arguments", "zero");
+    return;
+  }
+  device = args.device;
+
+  r = do_zero (device);
+  if (r == -1)
+    /* do_zero has already called reply_with_error */
+    goto done;
+
+  reply (NULL, NULL);
+done:
+  xdr_free ((xdrproc_t) xdr_guestfs_zero_args, (char *) &args);
+}
+
 void dispatch_incoming_message (XDR *xdr_in)
 {
   switch (proc_nr) {
@@ -2358,6 +2382,9 @@ void dispatch_incoming_message (XDR *xdr_in)
     case GUESTFS_PROC_FSCK:
       fsck_stub (xdr_in);
       break;
+    case GUESTFS_PROC_ZERO:
+      zero_stub (xdr_in);
+      break;
     default:
       reply_with_error ("dispatch_incoming_message: unknown procedure number %d", proc_nr);
   }
diff --git a/daemon/zero.c b/daemon/zero.c
new file mode 100644
index 00000000..2c20abc3
--- /dev/null
+++ b/daemon/zero.c
@@ -0,0 +1,52 @@
+/* libguestfs - the guestfsd daemon
+ * Copyright (C) 2009 Red Hat Inc. 
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "daemon.h"
+#include "actions.h"
+
+int
+do_zero (const char *device)
+{
+  int fd, i;
+  char buf[4096];
+
+  IS_DEVICE (device, -1);
+
+  fd = open (device, O_WRONLY);
+  if (fd == -1) {
+    reply_with_perror ("%s", device);
+    return -1;
+  }
+
+  memset (buf, 0, sizeof buf);
+
+  for (i = 0; i < 32; ++i)
+    (void) write (fd, buf, sizeof buf);
+
+  close (fd);
+
+  return 0;
+}
diff --git a/fish/cmds.c b/fish/cmds.c
index e762521a..c23da2f6 100644
--- a/fish/cmds.c
+++ b/fish/cmds.c
@@ -133,6 +133,7 @@ void list_commands (void)
   printf ("%-20s %s\n", "vgs", "list the LVM volume groups (VGs)");
   printf ("%-20s %s\n", "vgs-full", "list the LVM volume groups (VGs)");
   printf ("%-20s %s\n", "write-file", "create a file");
+  printf ("%-20s %s\n", "zero", "write zeroes to the device");
   printf ("    Use -h <cmd> / help <cmd> to show detailed help for a command.\n");
 }
 
@@ -444,6 +445,9 @@ void display_command (const char *cmd)
   if (strcasecmp (cmd, "fsck") == 0)
     pod2text ("fsck - run the filesystem checker", " fsck <fstype> <device>\n\nThis runs the filesystem checker (fsck) on C<device> which\nshould have filesystem type C<fstype>.\n\nThe returned integer is the status.  See L<fsck(8)> for the\nlist of status codes from C<fsck>, and note that multiple\nstatus codes can be summed together.\n\nIt is entirely equivalent to running C<fsck -a -t fstype device>.\nNote that checking or repairing NTFS volumes is not supported\n(by linux-ntfs).");
   else
+  if (strcasecmp (cmd, "zero") == 0)
+    pod2text ("zero - write zeroes to the device", " zero <device>\n\nThis command writes zeroes over the first few blocks of C<device>.\n\nHow many blocks are zeroed isn't specified (but it's I<not> enough\nto securely wipe the device).  It should be sufficient to remove\nany partition tables, filesystem superblocks and so on.");
+  else
     display_builtin_command (cmd);
 }
 
@@ -2164,6 +2168,20 @@ static int run_fsck (const char *cmd, int argc, char *argv[])
   return 0;
 }
 
+static int run_zero (const char *cmd, int argc, char *argv[])
+{
+  int r;
+  const char *device;
+  if (argc != 1) {
+    fprintf (stderr, "%s should have 1 parameter(s)\n", cmd);
+    fprintf (stderr, "type 'help %s' for help on %s\n", cmd, cmd);
+    return -1;
+  }
+  device = argv[0];
+  r = guestfs_zero (g, device);
+  return r;
+}
+
 int run_action (const char *cmd, int argc, char *argv[])
 {
   if (strcasecmp (cmd, "launch") == 0 || strcasecmp (cmd, "run") == 0)
@@ -2472,6 +2490,9 @@ int run_action (const char *cmd, int argc, char *argv[])
   if (strcasecmp (cmd, "fsck") == 0)
     return run_fsck (cmd, argc, argv);
   else
+  if (strcasecmp (cmd, "zero") == 0)
+    return run_zero (cmd, argc, argv);
+  else
     {
       fprintf (stderr, "%s: unknown command\n", cmd);
       return -1;
diff --git a/fish/completion.c b/fish/completion.c
index cafb84d1..cc9991fe 100644
--- a/fish/completion.c
+++ b/fish/completion.c
@@ -145,6 +145,7 @@ static const char *const commands[] = {
   "vgs",
   "vgs-full",
   "write-file",
+  "zero",
   NULL
 };
 
diff --git a/guestfish-actions.pod b/guestfish-actions.pod
index c1981c5e..d3912573 100644
--- a/guestfish-actions.pod
+++ b/guestfish-actions.pod
@@ -1107,3 +1107,13 @@ Because of the message protocol, there is a transfer limit
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.
 
+=head2 zero
+
+ zero device
+
+This command writes zeroes over the first few blocks of C<device>.
+
+How many blocks are zeroed isn't specified (but it's I<not> enough
+to securely wipe the device).  It should be sufficient to remove
+any partition tables, filesystem superblocks and so on.
+
diff --git a/guestfs-actions.pod b/guestfs-actions.pod
index 07b35af9..fb7c3db2 100644
--- a/guestfs-actions.pod
+++ b/guestfs-actions.pod
@@ -1507,3 +1507,16 @@ Because of the message protocol, there is a transfer limit
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.
 
+=head2 guestfs_zero
+
+ int guestfs_zero (guestfs_h *handle,
+		const char *device);
+
+This command writes zeroes over the first few blocks of C<device>.
+
+How many blocks are zeroed isn't specified (but it's I<not> enough
+to securely wipe the device).  It should be sufficient to remove
+any partition tables, filesystem superblocks and so on.
+
+This function returns 0 on success or -1 on error.
+
diff --git a/java/com/redhat/et/libguestfs/GuestFS.java b/java/com/redhat/et/libguestfs/GuestFS.java
index 844c3b33..293ee23e 100644
--- a/java/com/redhat/et/libguestfs/GuestFS.java
+++ b/java/com/redhat/et/libguestfs/GuestFS.java
@@ -2382,4 +2382,27 @@ public class GuestFS {
   private native int _fsck (long g, String fstype, String device)
     throws LibGuestFSException;
 
+  /**
+   * write zeroes to the device
+   *
+   * This command writes zeroes over the first few blocks of
+   * "device".
+   * 
+   * How many blocks are zeroed isn't specified (but it's
+   * *not* enough to securely wipe the device). It should be
+   * sufficient to remove any partition tables, filesystem
+   * superblocks and so on.
+   * 
+   * @throws LibGuestFSException
+   */
+  public void zero (String device)
+    throws LibGuestFSException
+  {
+    if (g == 0)
+      throw new LibGuestFSException ("zero: handle is closed");
+    _zero (g, device);
+  }
+  private native void _zero (long g, String device)
+    throws LibGuestFSException;
+
 }
diff --git a/java/com_redhat_et_libguestfs_GuestFS.c b/java/com_redhat_et_libguestfs_GuestFS.c
index 1f5579e2..466ced85 100644
--- a/java/com_redhat_et_libguestfs_GuestFS.c
+++ b/java/com_redhat_et_libguestfs_GuestFS.c
@@ -2420,3 +2420,20 @@ Java_com_redhat_et_libguestfs_GuestFS__1fsck
   return (jint) r;
 }
 
+JNIEXPORT void JNICALL
+Java_com_redhat_et_libguestfs_GuestFS__1zero
+  (JNIEnv *env, jobject obj, jlong jg, jstring jdevice)
+{
+  guestfs_h *g = (guestfs_h *) (long) jg;
+  int r;
+  const char *device;
+
+  device = (*env)->GetStringUTFChars (env, jdevice, NULL);
+  r = guestfs_zero (g, device);
+  (*env)->ReleaseStringUTFChars (env, jdevice, device);
+  if (r == -1) {
+    throw_exception (env, guestfs_last_error (g));
+    return ;
+  }
+}
+
diff --git a/ocaml/guestfs.ml b/ocaml/guestfs.ml
index 32e2264e..0d60bccf 100644
--- a/ocaml/guestfs.ml
+++ b/ocaml/guestfs.ml
@@ -220,3 +220,4 @@ external get_e2label : t -> string -> string = "ocaml_guestfs_get_e2label"
 external set_e2uuid : t -> string -> string -> unit = "ocaml_guestfs_set_e2uuid"
 external get_e2uuid : t -> string -> string = "ocaml_guestfs_get_e2uuid"
 external fsck : t -> string -> string -> int = "ocaml_guestfs_fsck"
+external zero : t -> string -> unit = "ocaml_guestfs_zero"
diff --git a/ocaml/guestfs.mli b/ocaml/guestfs.mli
index 2cbd7346..259c8f34 100644
--- a/ocaml/guestfs.mli
+++ b/ocaml/guestfs.mli
@@ -439,3 +439,6 @@ val get_e2uuid : t -> string -> string
 val fsck : t -> string -> string -> int
 (** run the filesystem checker *)
 
+val zero : t -> string -> unit
+(** write zeroes to the device *)
+
diff --git a/ocaml/guestfs_c_actions.c b/ocaml/guestfs_c_actions.c
index 22dc18f9..458d7a70 100644
--- a/ocaml/guestfs_c_actions.c
+++ b/ocaml/guestfs_c_actions.c
@@ -2823,3 +2823,26 @@ ocaml_guestfs_fsck (value gv, value fstypev, value devicev)
   CAMLreturn (rv);
 }
 
+CAMLprim value
+ocaml_guestfs_zero (value gv, value devicev)
+{
+  CAMLparam2 (gv, devicev);
+  CAMLlocal1 (rv);
+
+  guestfs_h *g = Guestfs_val (gv);
+  if (g == NULL)
+    caml_failwith ("zero: used handle after closing it");
+
+  const char *device = String_val (devicev);
+  int r;
+
+  caml_enter_blocking_section ();
+  r = guestfs_zero (g, device);
+  caml_leave_blocking_section ();
+  if (r == -1)
+    ocaml_guestfs_raise_error (g, "zero");
+
+  rv = Val_unit;
+  CAMLreturn (rv);
+}
+
diff --git a/perl/Guestfs.xs b/perl/Guestfs.xs
index 38c60c21..651e7a23 100644
--- a/perl/Guestfs.xs
+++ b/perl/Guestfs.xs
@@ -1588,3 +1588,14 @@ PREINIT:
  OUTPUT:
       RETVAL
 
+void
+zero (g, device)
+      guestfs_h *g;
+      char *device;
+PREINIT:
+      int r;
+ PPCODE:
+      r = guestfs_zero (g, device);
+      if (r == -1)
+        croak ("zero: %s", guestfs_last_error (g));
+
diff --git a/perl/lib/Sys/Guestfs.pm b/perl/lib/Sys/Guestfs.pm
index 5b87b27e..2d75b69f 100644
--- a/perl/lib/Sys/Guestfs.pm
+++ b/perl/lib/Sys/Guestfs.pm
@@ -1006,6 +1006,14 @@ Because of the message protocol, there is a transfer limit
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.
 
+=item $h->zero ($device);
+
+This command writes zeroes over the first few blocks of C<device>.
+
+How many blocks are zeroed isn't specified (but it's I<not> enough
+to securely wipe the device).  It should be sufficient to remove
+any partition tables, filesystem superblocks and so on.
+
 =cut
 
 1;
diff --git a/python/guestfs-py.c b/python/guestfs-py.c
index 6b93b276..a1cfb09d 100644
--- a/python/guestfs-py.c
+++ b/python/guestfs-py.c
@@ -3027,6 +3027,31 @@ py_guestfs_fsck (PyObject *self, PyObject *args)
   return py_r;
 }
 
+static PyObject *
+py_guestfs_zero (PyObject *self, PyObject *args)
+{
+  PyObject *py_g;
+  guestfs_h *g;
+  PyObject *py_r;
+  int r;
+  const char *device;
+
+  if (!PyArg_ParseTuple (args, (char *) "Os:guestfs_zero",
+                         &py_g, &device))
+    return NULL;
+  g = get_handle (py_g);
+
+  r = guestfs_zero (g, device);
+  if (r == -1) {
+    PyErr_SetString (PyExc_RuntimeError, guestfs_last_error (g));
+    return NULL;
+  }
+
+  Py_INCREF (Py_None);
+  py_r = Py_None;
+  return py_r;
+}
+
 static PyMethodDef methods[] = {
   { (char *) "create", py_guestfs_create, METH_VARARGS, NULL },
   { (char *) "close", py_guestfs_close, METH_VARARGS, NULL },
@@ -3135,6 +3160,7 @@ static PyMethodDef methods[] = {
   { (char *) "set_e2uuid", py_guestfs_set_e2uuid, METH_VARARGS, NULL },
   { (char *) "get_e2uuid", py_guestfs_get_e2uuid, METH_VARARGS, NULL },
   { (char *) "fsck", py_guestfs_fsck, METH_VARARGS, NULL },
+  { (char *) "zero", py_guestfs_zero, METH_VARARGS, NULL },
   { NULL, NULL, 0, NULL }
 };
 
diff --git a/python/guestfs.py b/python/guestfs.py
index 37dce2bf..3cfc86a1 100644
--- a/python/guestfs.py
+++ b/python/guestfs.py
@@ -1163,3 +1163,14 @@ class GuestFS:
         """
         return libguestfsmod.fsck (self._o, fstype, device)
 
+    def zero (self, device):
+        u"""This command writes zeroes over the first few blocks of
+        "device".
+        
+        How many blocks are zeroed isn't specified (but it's
+        *not* enough to securely wipe the device). It should be
+        sufficient to remove any partition tables, filesystem
+        superblocks and so on.
+        """
+        return libguestfsmod.zero (self._o, device)
+
diff --git a/ruby/ext/guestfs/_guestfs.c b/ruby/ext/guestfs/_guestfs.c
index 56b3f217..1e87d043 100644
--- a/ruby/ext/guestfs/_guestfs.c
+++ b/ruby/ext/guestfs/_guestfs.c
@@ -2540,6 +2540,27 @@ static VALUE ruby_guestfs_fsck (VALUE gv, VALUE fstypev, VALUE devicev)
   return INT2NUM (r);
 }
 
+static VALUE ruby_guestfs_zero (VALUE gv, VALUE devicev)
+{
+  guestfs_h *g;
+  Data_Get_Struct (gv, guestfs_h, g);
+  if (!g)
+    rb_raise (rb_eArgError, "%s: used handle after closing it", "zero");
+
+  const char *device = StringValueCStr (devicev);
+  if (!device)
+    rb_raise (rb_eTypeError, "expected string for parameter %s of %s",
+              "device", "zero");
+
+  int r;
+
+  r = guestfs_zero (g, device);
+  if (r == -1)
+    rb_raise (e_Error, "%s", guestfs_last_error (g));
+
+  return Qnil;
+}
+
 /* Initialize the module. */
 void Init__guestfs ()
 {
@@ -2760,4 +2781,6 @@ void Init__guestfs ()
         ruby_guestfs_get_e2uuid, 1);
   rb_define_method (c_guestfs, "fsck",
         ruby_guestfs_fsck, 2);
+  rb_define_method (c_guestfs, "zero",
+        ruby_guestfs_zero, 1);
 }
diff --git a/src/generator.ml b/src/generator.ml
index 615d32ec..8d5450d1 100755
--- a/src/generator.ml
+++ b/src/generator.ml
@@ -1633,8 +1633,13 @@ This returns the ext2/3/4 filesystem UUID of the filesystem on
 C<device>.");
 
   ("fsck", (RInt "status", [String "fstype"; String "device"]), 84, [],
-   [InitBasicFS, TestRun (
-      [["fsck"; "ext2"; "/dev/sda1"]])],
+   [InitBasicFS, TestOutputInt (
+      [["umount"; "/dev/sda1"];
+       ["fsck"; "ext2"; "/dev/sda1"]], 0);
+    InitBasicFS, TestOutputInt (
+      [["umount"; "/dev/sda1"];
+       ["zero"; "/dev/sda1"];
+       ["fsck"; "ext2"; "/dev/sda1"]], 8)],
    "run the filesystem checker",
    "\
 This runs the filesystem checker (fsck) on C<device> which
@@ -1647,6 +1652,21 @@ status codes can be summed together.
 It is entirely equivalent to running C<fsck -a -t fstype device>.
 Note that checking or repairing NTFS volumes is not supported
 (by linux-ntfs).");
+
+  ("zero", (RErr, [String "device"]), 85, [],
+   [InitBasicFS, TestOutput (
+      [["umount"; "/dev/sda1"];
+       ["zero"; "/dev/sda1"];
+       ["file"; "/dev/sda1"]], "data")],
+   "write zeroes to the device",
+   "\
+This command writes zeroes over the first few blocks of C<device>.
+
+How many blocks are zeroed isn't specified (but it's I<not> enough
+to securely wipe the device).  It should be sufficient to remove
+any partition tables, filesystem superblocks and so on.");
+
+
 ]
 
 let all_functions = non_daemon_functions @ daemon_functions
diff --git a/src/guestfs-actions.c b/src/guestfs-actions.c
index a075b802..e2da1c3a 100644
--- a/src/guestfs-actions.c
+++ b/src/guestfs-actions.c
@@ -7642,3 +7642,89 @@ int guestfs_fsck (guestfs_h *g,
   return ctx.ret.status;
 }
 
+struct zero_ctx {
+  /* This flag is set by the callbacks, so we know we've done
+   * the callbacks as expected, and in the right sequence.
+   * 0 = not called, 1 = reply_cb called.
+   */
+  int cb_sequence;
+  struct guestfs_message_header hdr;
+  struct guestfs_message_error err;
+};
+
+static void zero_reply_cb (guestfs_h *g, void *data, XDR *xdr)
+{
+  guestfs_main_loop *ml = guestfs_get_main_loop (g);
+  struct zero_ctx *ctx = (struct zero_ctx *) data;
+
+  /* This should definitely not happen. */
+  if (ctx->cb_sequence != 0) {
+    ctx->cb_sequence = 9999;
+    error (g, "%s: internal error: reply callback called twice", "guestfs_zero");
+    return;
+  }
+
+  ml->main_loop_quit (ml, g);
+
+  if (!xdr_guestfs_message_header (xdr, &ctx->hdr)) {
+    error (g, "%s: failed to parse reply header", "guestfs_zero");
+    return;
+  }
+  if (ctx->hdr.status == GUESTFS_STATUS_ERROR) {
+    if (!xdr_guestfs_message_error (xdr, &ctx->err)) {
+      error (g, "%s: failed to parse reply error", "guestfs_zero");
+      return;
+    }
+    goto done;
+  }
+ done:
+  ctx->cb_sequence = 1;
+}
+
+int guestfs_zero (guestfs_h *g,
+		const char *device)
+{
+  struct guestfs_zero_args args;
+  struct zero_ctx ctx;
+  guestfs_main_loop *ml = guestfs_get_main_loop (g);
+  int serial;
+
+  if (check_state (g, "guestfs_zero") == -1) return -1;
+  guestfs_set_busy (g);
+
+  memset (&ctx, 0, sizeof ctx);
+
+  args.device = (char *) device;
+  serial = guestfs__send_sync (g, GUESTFS_PROC_ZERO,
+        (xdrproc_t) xdr_guestfs_zero_args, (char *) &args);
+  if (serial == -1) {
+    guestfs_set_ready (g);
+    return -1;
+  }
+
+  guestfs__switch_to_receiving (g);
+  ctx.cb_sequence = 0;
+  guestfs_set_reply_callback (g, zero_reply_cb, &ctx);
+  (void) ml->main_loop_run (ml, g);
+  guestfs_set_reply_callback (g, NULL, NULL);
+  if (ctx.cb_sequence != 1) {
+    error (g, "%s reply failed, see earlier error messages", "guestfs_zero");
+    guestfs_set_ready (g);
+    return -1;
+  }
+
+  if (check_reply_header (g, &ctx.hdr, GUESTFS_PROC_ZERO, serial) == -1) {
+    guestfs_set_ready (g);
+    return -1;
+  }
+
+  if (ctx.hdr.status == GUESTFS_STATUS_ERROR) {
+    error (g, "%s", ctx.err.error_message);
+    guestfs_set_ready (g);
+    return -1;
+  }
+
+  guestfs_set_ready (g);
+  return 0;
+}
+
diff --git a/src/guestfs-actions.h b/src/guestfs-actions.h
index 6e56099a..0fc62a18 100644
--- a/src/guestfs-actions.h
+++ b/src/guestfs-actions.h
@@ -124,3 +124,4 @@ extern char *guestfs_get_e2label (guestfs_h *handle, const char *device);
 extern int guestfs_set_e2uuid (guestfs_h *handle, const char *device, const char *uuid);
 extern char *guestfs_get_e2uuid (guestfs_h *handle, const char *device);
 extern int guestfs_fsck (guestfs_h *handle, const char *fstype, const char *device);
+extern int guestfs_zero (guestfs_h *handle, const char *device);
diff --git a/src/guestfs_protocol.c b/src/guestfs_protocol.c
index 16e80f17..b12133a0 100644
--- a/src/guestfs_protocol.c
+++ b/src/guestfs_protocol.c
@@ -1450,6 +1450,16 @@ xdr_guestfs_fsck_ret (XDR *xdrs, guestfs_fsck_ret *objp)
 }
 
 bool_t
+xdr_guestfs_zero_args (XDR *xdrs, guestfs_zero_args *objp)
+{
+	register int32_t *buf;
+
+	 if (!xdr_string (xdrs, &objp->device, ~0))
+		 return FALSE;
+	return TRUE;
+}
+
+bool_t
 xdr_guestfs_procedure (XDR *xdrs, guestfs_procedure *objp)
 {
 	register int32_t *buf;
diff --git a/src/guestfs_protocol.h b/src/guestfs_protocol.h
index 64e4b4db..2e79669c 100644
--- a/src/guestfs_protocol.h
+++ b/src/guestfs_protocol.h
@@ -750,6 +750,11 @@ struct guestfs_fsck_ret {
 };
 typedef struct guestfs_fsck_ret guestfs_fsck_ret;
 
+struct guestfs_zero_args {
+	char *device;
+};
+typedef struct guestfs_zero_args guestfs_zero_args;
+
 enum guestfs_procedure {
 	GUESTFS_PROC_MOUNT = 1,
 	GUESTFS_PROC_SYNC = 2,
@@ -835,7 +840,8 @@ enum guestfs_procedure {
 	GUESTFS_PROC_SET_E2UUID = 82,
 	GUESTFS_PROC_GET_E2UUID = 83,
 	GUESTFS_PROC_FSCK = 84,
-	GUESTFS_PROC_NR_PROCS = 84 + 1,
+	GUESTFS_PROC_ZERO = 85,
+	GUESTFS_PROC_NR_PROCS = 85 + 1,
 };
 typedef enum guestfs_procedure guestfs_procedure;
 #define GUESTFS_MESSAGE_MAX 4194304
@@ -1002,6 +1008,7 @@ extern  bool_t xdr_guestfs_get_e2uuid_args (XDR *, guestfs_get_e2uuid_args*);
 extern  bool_t xdr_guestfs_get_e2uuid_ret (XDR *, guestfs_get_e2uuid_ret*);
 extern  bool_t xdr_guestfs_fsck_args (XDR *, guestfs_fsck_args*);
 extern  bool_t xdr_guestfs_fsck_ret (XDR *, guestfs_fsck_ret*);
+extern  bool_t xdr_guestfs_zero_args (XDR *, guestfs_zero_args*);
 extern  bool_t xdr_guestfs_procedure (XDR *, guestfs_procedure*);
 extern  bool_t xdr_guestfs_message_direction (XDR *, guestfs_message_direction*);
 extern  bool_t xdr_guestfs_message_status (XDR *, guestfs_message_status*);
@@ -1127,6 +1134,7 @@ extern bool_t xdr_guestfs_get_e2uuid_args ();
 extern bool_t xdr_guestfs_get_e2uuid_ret ();
 extern bool_t xdr_guestfs_fsck_args ();
 extern bool_t xdr_guestfs_fsck_ret ();
+extern bool_t xdr_guestfs_zero_args ();
 extern bool_t xdr_guestfs_procedure ();
 extern bool_t xdr_guestfs_message_direction ();
 extern bool_t xdr_guestfs_message_status ();
diff --git a/src/guestfs_protocol.x b/src/guestfs_protocol.x
index 92dc8eac..c940bf44 100644
--- a/src/guestfs_protocol.x
+++ b/src/guestfs_protocol.x
@@ -582,6 +582,10 @@ struct guestfs_fsck_ret {
   int status;
 };
 
+struct guestfs_zero_args {
+  string device<>;
+};
+
 enum guestfs_procedure {
   GUESTFS_PROC_MOUNT = 1,
   GUESTFS_PROC_SYNC = 2,
@@ -667,6 +671,7 @@ enum guestfs_procedure {
   GUESTFS_PROC_SET_E2UUID = 82,
   GUESTFS_PROC_GET_E2UUID = 83,
   GUESTFS_PROC_FSCK = 84,
+  GUESTFS_PROC_ZERO = 85,
   GUESTFS_PROC_NR_PROCS
 };
 
diff --git a/tests.c b/tests.c
index dddb9715..5cf8ddc4 100644
--- a/tests.c
+++ b/tests.c
@@ -112,6 +112,78 @@ static void no_test_warnings (void)
   fprintf (stderr, "warning: \"guestfs_get_e2uuid\" has no tests\n");
 }
 
+static int test_zero_0 (void)
+{
+  /* InitBasicFS for zero (0): create ext2 on /dev/sda1 */
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_umount_all (g);
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_lvm_remove_all (g);
+    if (r == -1)
+      return -1;
+  }
+  {
+    char *lines[] = {
+      ",",
+      NULL
+    };
+    int r;
+    suppress_error = 0;
+    r = guestfs_sfdisk (g, "/dev/sda", 0, 0, 0, lines);
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_mkfs (g, "ext2", "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_mount (g, "/dev/sda1", "/");
+    if (r == -1)
+      return -1;
+  }
+  /* TestOutput for zero (0) */
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_umount (g, "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_zero (g, "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
+  {
+    char *r;
+    suppress_error = 0;
+    r = guestfs_file (g, "/dev/sda1");
+    if (r == NULL)
+      return -1;
+    if (strcmp (r, "data") != 0) {
+      fprintf (stderr, "test_zero_0: expected \"data\" but got \"%s\"\n", r);
+      return -1;
+    }
+    free (r);
+  }
+  return 0;
+}
+
 static int test_fsck_0 (void)
 {
   /* InitBasicFS for fsck (0): create ext2 on /dev/sda1 */
@@ -154,13 +226,95 @@ static int test_fsck_0 (void)
     if (r == -1)
       return -1;
   }
-  /* TestRun for fsck (0) */
+  /* TestOutputInt for fsck (0) */
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_umount (g, "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
   {
     int r;
     suppress_error = 0;
     r = guestfs_fsck (g, "ext2", "/dev/sda1");
     if (r == -1)
       return -1;
+    if (r != 0) {
+      fprintf (stderr, "test_fsck_0: expected 0 but got %d\n",               (int) r);
+      return -1;
+    }
+  }
+  return 0;
+}
+
+static int test_fsck_1 (void)
+{
+  /* InitBasicFS for fsck (1): create ext2 on /dev/sda1 */
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_umount_all (g);
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_lvm_remove_all (g);
+    if (r == -1)
+      return -1;
+  }
+  {
+    char *lines[] = {
+      ",",
+      NULL
+    };
+    int r;
+    suppress_error = 0;
+    r = guestfs_sfdisk (g, "/dev/sda", 0, 0, 0, lines);
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_mkfs (g, "ext2", "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_mount (g, "/dev/sda1", "/");
+    if (r == -1)
+      return -1;
+  }
+  /* TestOutputInt for fsck (1) */
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_umount (g, "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_zero (g, "/dev/sda1");
+    if (r == -1)
+      return -1;
+  }
+  {
+    int r;
+    suppress_error = 0;
+    r = guestfs_fsck (g, "ext2", "/dev/sda1");
+    if (r == -1)
+      return -1;
+    if (r != 8) {
+      fprintf (stderr, "test_fsck_1: expected 8 but got %d\n",               (int) r);
+      return -1;
+    }
   }
   return 0;
 }
@@ -6566,15 +6720,27 @@ int main (int argc, char *argv[])
     exit (1);
   }
 
-  nr_tests = 92;
+  nr_tests = 94;
 
   test_num++;
+  printf ("%3d/%3d test_zero_0\n", test_num, nr_tests);
+  if (test_zero_0 () == -1) {
+    printf ("test_zero_0 FAILED\n");
+    failed++;
+  }
+  test_num++;
   printf ("%3d/%3d test_fsck_0\n", test_num, nr_tests);
   if (test_fsck_0 () == -1) {
     printf ("test_fsck_0 FAILED\n");
     failed++;
   }
   test_num++;
+  printf ("%3d/%3d test_fsck_1\n", test_num, nr_tests);
+  if (test_fsck_1 () == -1) {
+    printf ("test_fsck_1 FAILED\n");
+    failed++;
+  }
+  test_num++;
   printf ("%3d/%3d test_set_e2uuid_0\n", test_num, nr_tests);
   if (test_set_e2uuid_0 () == -1) {
     printf ("test_set_e2uuid_0 FAILED\n");