Merge mainline into keylayouts

grub-core/normal/auth.c

@@ -0,0 +1,250 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2009  Free Software Foundation, Inc.
+ *
+ *  GRUB 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/auth.h>
+#include <grub/list.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/env.h>
+#include <grub/normal.h>
+#include <grub/time.h>
+#include <grub/i18n.h>
+
+struct grub_auth_user
+{
+  struct grub_auth_user *next;
+  char *name;
+  grub_auth_callback_t callback;
+  void *arg;
+  int authenticated;
+};
+
+struct grub_auth_user *users = NULL;
+
+grub_err_t
+grub_auth_register_authentication (const char *user,
+				   grub_auth_callback_t callback,
+				   void *arg)
+{
+  struct grub_auth_user *cur;
+
+  cur = grub_named_list_find (GRUB_AS_NAMED_LIST (users), user);
+  if (!cur)
+    cur = grub_zalloc (sizeof (*cur));
+  if (!cur)
+    return grub_errno;
+  cur->callback = callback;
+  cur->arg = arg;
+  if (! cur->name)
+    {
+      cur->name = grub_strdup (user);
+      if (!cur->name)
+	{
+	  grub_free (cur);
+	  return grub_errno;
+	}
+      grub_list_push (GRUB_AS_LIST_P (&users), GRUB_AS_LIST (cur));
+    }
+  return GRUB_ERR_NONE;
+}
+
+grub_err_t
+grub_auth_unregister_authentication (const char *user)
+{
+  struct grub_auth_user *cur;
+  cur = grub_named_list_find (GRUB_AS_NAMED_LIST (users), user);
+  if (!cur)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "user '%s' not found", user);
+  if (!cur->authenticated)
+    {
+      grub_free (cur->name);
+      grub_list_remove (GRUB_AS_LIST_P (&users), GRUB_AS_LIST (cur));
+      grub_free (cur);
+    }
+  else
+    {
+      cur->callback = NULL;
+      cur->arg = NULL;
+    }
+  return GRUB_ERR_NONE;
+}
+
+grub_err_t
+grub_auth_authenticate (const char *user)
+{
+  struct grub_auth_user *cur;
+
+  cur = grub_named_list_find (GRUB_AS_NAMED_LIST (users), user);
+  if (!cur)
+    cur = grub_zalloc (sizeof (*cur));
+  if (!cur)
+    return grub_errno;
+
+  cur->authenticated = 1;
+
+  if (! cur->name)
+    {
+      cur->name = grub_strdup (user);
+      if (!cur->name)
+	{
+	  grub_free (cur);
+	  return grub_errno;
+	}
+      grub_list_push (GRUB_AS_LIST_P (&users), GRUB_AS_LIST (cur));
+    }
+
+  return GRUB_ERR_NONE;
+}
+
+grub_err_t
+grub_auth_deauthenticate (const char *user)
+{
+  struct grub_auth_user *cur;
+  cur = grub_named_list_find (GRUB_AS_NAMED_LIST (users), user);
+  if (!cur)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "user '%s' not found", user);
+  if (!cur->callback)
+    {
+      grub_free (cur->name);
+      grub_list_remove (GRUB_AS_LIST_P (&users), GRUB_AS_LIST (cur));
+      grub_free (cur);
+    }
+  else
+    cur->authenticated = 0;
+  return GRUB_ERR_NONE;
+}
+
+static int
+is_authenticated (const char *userlist)
+{
+  const char *superusers;
+  struct grub_auth_user *user;
+
+  superusers = grub_env_get ("superusers");
+
+  if (!superusers)
+    return 1;
+
+  FOR_LIST_ELEMENTS (user, users)
+    {
+      if (!(user->authenticated))
+	continue;
+
+      if ((userlist && grub_strword (userlist, user->name))
+	  || grub_strword (superusers, user->name))
+	return 1;
+    }
+
+  return 0;
+}
+
+static int
+grub_username_get (char buf[], unsigned buf_size)
+{
+  unsigned cur_len = 0;
+  int key;
+
+  while (1)
+    {
+      key = grub_getkey (); 
+      if (key == '\n' || key == '\r')
+	break;
+
+      if (key == '\e')
+	{
+	  cur_len = 0;
+	  break;
+	}
+
+      if (key == '\b')
+	{
+	  cur_len--;
+	  grub_printf ("\b");
+	  continue;
+	}
+
+      if (!grub_isprint (key))
+	continue;
+
+      if (cur_len + 2 < buf_size)
+	{
+	  buf[cur_len++] = key;
+	  grub_printf ("%c", key);
+	}
+    }
+
+  grub_memset (buf + cur_len, 0, buf_size - cur_len);
+
+  grub_xputs ("\n");
+  grub_refresh ();
+
+  return (key != '\e');
+}
+
+grub_err_t
+grub_auth_check_authentication (const char *userlist)
+{
+  char login[1024];
+  struct grub_auth_user *cur = NULL;
+  grub_err_t err;
+  static unsigned long punishment_delay = 1;
+  char entered[GRUB_AUTH_MAX_PASSLEN];
+  struct grub_auth_user *user;
+
+  grub_memset (login, 0, sizeof (login));
+
+  if (is_authenticated (userlist))
+    {
+      punishment_delay = 1;
+      return GRUB_ERR_NONE;
+    }
+
+  grub_puts_ (N_("Enter username: "));
+
+  if (!grub_username_get (login, sizeof (login) - 1))
+    goto access_denied;
+
+  grub_puts_ (N_("Enter password: "));
+
+  if (!grub_password_get (entered, GRUB_AUTH_MAX_PASSLEN))
+    goto access_denied;
+
+  FOR_LIST_ELEMENTS (user, users)
+    {
+      if (grub_strcmp (login, user->name) == 0)
+	cur = user;
+    }
+
+  if (!cur || ! cur->callback)
+    goto access_denied;
+
+  err = cur->callback (login, entered, cur->arg);
+  if (is_authenticated (userlist))
+    {
+      punishment_delay = 1;
+      return GRUB_ERR_NONE;
+    }
+
+ access_denied:
+  grub_sleep (punishment_delay);
+
+  if (punishment_delay < GRUB_ULONG_MAX / 2)
+    punishment_delay *= 2;
+
+  return GRUB_ACCESS_DENIED;
+}