1  /* Copyright (C) 1993-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <hurd.h>
      19  #include <hurd/id.h>
      20  
      21  /* Set the uid set for the current user to UIDS (N of them).  */
      22  int
      23  seteuids (int n, const uid_t *uids)
      24  {
      25    error_t err;
      26    auth_t newauth;
      27    int i;
      28    gid_t new[n];
      29  
      30    /* Fault before taking locks.  */
      31    for (i = 0; i < n; ++i)
      32      new[i] = uids[i];
      33  
      34  retry:
      35    HURD_CRITICAL_BEGIN;
      36    __mutex_lock (&_hurd_id.lock);
      37    err = _hurd_check_ids ();
      38    if (! err)
      39      {
      40        /* Get a new auth port using those IDs.  */
      41        err = __USEPORT (AUTH,
      42  		       __auth_makeauth (port, NULL, 0, 0,
      43  					new, n,
      44  					_hurd_id.aux.uids, _hurd_id.aux.nuids,
      45  					_hurd_id.gen.gids, _hurd_id.gen.ngids,
      46  					_hurd_id.aux.gids, _hurd_id.aux.ngids,
      47  					&newauth));
      48      }
      49    __mutex_unlock (&_hurd_id.lock);
      50    HURD_CRITICAL_END;
      51    if (err == EINTR)
      52      /* Got a signal while inside an RPC of the critical section, retry again */
      53      goto retry;
      54  
      55    if (err)
      56      return __hurd_fail (err);
      57  
      58    /* Install the new auth port and reauthenticate everything.  */
      59    err = __setauth (newauth);
      60    __mach_port_deallocate (__mach_task_self (), newauth);
      61    return err;
      62  }