2 bd8683d0 2022-12-02 op * Copyright (c) 2004, 2005 Darren Tucker (dtucker at zip com au).
4 bd8683d0 2022-12-02 op * Permission to use, copy, modify, and distribute this software for any
5 bd8683d0 2022-12-02 op * purpose with or without fee is hereby granted, provided that the above
6 bd8683d0 2022-12-02 op * copyright notice and this permission notice appear in all copies.
8 bd8683d0 2022-12-02 op * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 bd8683d0 2022-12-02 op * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 bd8683d0 2022-12-02 op * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 bd8683d0 2022-12-02 op * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 bd8683d0 2022-12-02 op * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 bd8683d0 2022-12-02 op * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 bd8683d0 2022-12-02 op * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 2d0a2b21 2023-06-23 op #include "../config.h"
19 bd8683d0 2022-12-02 op #include <sys/types.h>
21 bd8683d0 2022-12-02 op #include <errno.h>
22 bd8683d0 2022-12-02 op #include <unistd.h>
25 bd8683d0 2022-12-02 op setresuid(uid_t ruid, uid_t euid, uid_t suid)
30 bd8683d0 2022-12-02 op /* Allow only the tested configuration. */
32 bd8683d0 2022-12-02 op if (ruid != euid || euid != suid) {
33 bd8683d0 2022-12-02 op errno = ENOSYS;
36 bd8683d0 2022-12-02 op ouid = getuid();
38 bd8683d0 2022-12-02 op if ((ret = setreuid(euid, euid)) == -1)
42 bd8683d0 2022-12-02 op * When real, effective and saved uids are the same and we have
43 bd8683d0 2022-12-02 op * changed uids, sanity check that we cannot restore the old uid.
46 bd8683d0 2022-12-02 op if (ruid == euid && euid == suid && ouid != ruid &&
47 bd8683d0 2022-12-02 op setuid(ouid) != -1 && seteuid(ouid) != -1) {
48 bd8683d0 2022-12-02 op errno = EINVAL;
53 bd8683d0 2022-12-02 op * Finally, check that the real and effective uids are what we
56 bd8683d0 2022-12-02 op if (getuid() != ruid || geteuid() != euid) {
57 bd8683d0 2022-12-02 op errno = EACCES;