Initial checkin

1 files changed, 90 insertions, 0 deletions

diff --git a/utils/unsu.c b/utils/unsu.c
new file mode 100644
index 00000000..4672821b
--- /dev/null
+++ b/utils/unsu.c
@@ -0,0 +1,90 @@
+/* Attempt to undo a previous su
+
+   Copyright (C) 1997 Free Software Foundation, Inc.
+
+   Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+   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, 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <hurd.h>
+#include <argp.h>
+#include <error.h>
+#include <version.h>
+
+#include "frobauth.h"
+#include "pids.h"
+
+const char *argp_program_version = STANDARD_HURD_VERSION (rmauth);
+
+static struct argp_child child_argps[] = {{ &frobauth_no_ugids_argp }, { 0 }};
+
+static char doc[] =
+  "Attempt to undo a previous su"
+  "\vThis command is convenient, but will only correctly undo a limited"
+  " subset of possible su commands.  It works by simply deleting all"
+  " current effective ids and the first two available ids, and then"
+  " making the first remaining available id the current effective id.";
+
+void 
+main (int argc, char *argv[])
+{
+  struct frobauth frobauth = FROBAUTH_INIT;
+
+  /* Modify UGIDS, to be what PID's new authentication should be, NOISE is
+     ignored.  */
+  error_t modify (struct ugids *ugids, const struct ugids *noise,
+		  pid_t pid, void *hook)
+    {
+      error_t err = 0;
+
+      idvec_clear (&ugids->eff_uids);
+      idvec_clear (&ugids->eff_gids);
+      idvec_clear (&ugids->imp_eff_gids);
+
+      idvec_delete (&ugids->avail_uids, 0);
+      idvec_delete (&ugids->avail_uids, 0);
+
+      idvec_delete (&ugids->avail_gids, 0);
+      idvec_delete (&ugids->avail_gids, 0);
+      idvec_keep (&ugids->imp_avail_gids, &ugids->avail_gids);
+
+      if (ugids->avail_uids.num > 0)
+	err = ugids_set_posix_user (ugids, ugids->avail_uids.ids[0]);
+
+      return err;
+    }
+  void print_info (const struct ugids *new,
+		   const struct ugids *old,
+		   const struct ugids *removed,
+		   pid_t pid, void *hook)
+    {
+      char *new_rep = ugids_rep (new, 1, 1, 0, 0, 0);
+      printf ("%d: Changed auth to %s\n", pid, new_rep);
+      free (new_rep);
+    }
+  struct argp argp = { 0, 0, 0, doc, child_argps };
+
+  /* Parse our command line.  This shouldn't ever return an error.  */
+  argp_parse (&argp, argc, argv, 0, 0, &frobauth);
+
+  if (frobauth_modify (&frobauth, modify, print_info, 0))
+    exit (0);
+  else
+    exit (1);
+}