| xf.li | bfc6e71 | 2025-02-07 01:54:34 -0800 | [diff] [blame^] | 1 | /* Copyright (C) 1991-2016 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 | <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <errno.h> |
| 19 | #include <unistd.h> |
| 20 | #include <sys/types.h> |
| 21 | #include <hurd.h> |
| 22 | #include <hurd/id.h> |
| 23 | #include <string.h> |
| 24 | |
| 25 | /* Set the user ID of the calling process to UID. |
| 26 | If the calling process is the super-user, the real |
| 27 | and effective user IDs, and the saved set-user-ID to UID; |
| 28 | if not, the effective user ID is set to UID. */ |
| 29 | int |
| 30 | __setuid (uid_t uid) |
| 31 | { |
| 32 | auth_t newauth; |
| 33 | error_t err; |
| 34 | |
| 35 | HURD_CRITICAL_BEGIN; |
| 36 | __mutex_lock (&_hurd_id.lock); |
| 37 | err = _hurd_check_ids (); |
| 38 | |
| 39 | if (!err) |
| 40 | { |
| 41 | /* Make a new auth handle which has UID as the real uid, |
| 42 | and as the first element in the list of effective uids. */ |
| 43 | |
| 44 | uid_t *newgen, *newaux, auxbuf[2]; |
| 45 | size_t ngen, naux; |
| 46 | |
| 47 | newaux = _hurd_id.aux.uids; |
| 48 | naux = _hurd_id.aux.nuids; |
| 49 | if (_hurd_id.gen.nuids == 0) |
| 50 | { |
| 51 | /* No effective uids now. The new set will be just UID. */ |
| 52 | newgen = &uid; |
| 53 | ngen = 1; |
| 54 | } |
| 55 | else if (_hurd_id.gen.uids[0] == 0) |
| 56 | { |
| 57 | /* We are root; set the effective, real, and saved to UID. */ |
| 58 | _hurd_id.gen.uids[0] = uid; |
| 59 | _hurd_id.valid = 0; |
| 60 | newgen = _hurd_id.gen.uids; |
| 61 | ngen = _hurd_id.gen.nuids; |
| 62 | if (_hurd_id.aux.nuids < 2) |
| 63 | { |
| 64 | newaux = auxbuf; |
| 65 | naux = 2; |
| 66 | } |
| 67 | newaux[0] = newaux[1] = uid; |
| 68 | } |
| 69 | else |
| 70 | { |
| 71 | /* We are not root; just change the effective UID. */ |
| 72 | /* XXX that implies an unprivileged setuid(0) will give |
| 73 | the caller root, no questions asked! */ |
| 74 | _hurd_id.gen.uids[0] = uid; |
| 75 | _hurd_id.valid = 0; |
| 76 | newgen = _hurd_id.gen.uids; |
| 77 | ngen = _hurd_id.gen.nuids; |
| 78 | } |
| 79 | |
| 80 | err = __USEPORT (AUTH, __auth_makeauth |
| 81 | (port, NULL, MACH_MSG_TYPE_COPY_SEND, 0, |
| 82 | newgen, ngen, newaux, naux, |
| 83 | _hurd_id.gen.gids, _hurd_id.gen.ngids, |
| 84 | _hurd_id.aux.gids, _hurd_id.aux.ngids, |
| 85 | &newauth)); |
| 86 | } |
| 87 | __mutex_unlock (&_hurd_id.lock); |
| 88 | HURD_CRITICAL_END; |
| 89 | |
| 90 | if (err) |
| 91 | return __hurd_fail (err); |
| 92 | |
| 93 | /* Install the new handle and reauthenticate everything. */ |
| 94 | err = __setauth (newauth); |
| 95 | __mach_port_deallocate (__mach_task_self (), newauth); |
| 96 | return err; |
| 97 | } |
| 98 | |
| 99 | weak_alias (__setuid, setuid) |