59 lines
1.2 KiB
C
59 lines
1.2 KiB
C
|
/*
|
||
|
|
* Umounts a previously bind mounted filesystem mountpoint,
|
||
|
|
* by using the CAP_SYS_ADMIN capability set on the file.
|
||
|
|
*
|
||
|
|
* Juan RP - 2010/04/26 - Public Domain.
|
||
|
|
*/
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <stdbool.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <sys/mount.h>
|
||
|
|
#include <sys/capability.h>
|
||
|
|
|
||
|
|
void
|
||
|
|
usage(void)
|
||
|
|
{
|
||
|
|
fprintf(stderr, "Usage: xbps-src-capbumount <dest>\n");
|
||
|
|
exit(EXIT_FAILURE);
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
main(int argc, char **argv)
|
||
|
|
{
|
||
|
|
cap_t cap;
|
||
|
|
cap_flag_value_t effective, permitted;
|
||
|
|
int rv;
|
||
|
|
|
||
|
|
if (argc != 2)
|
||
|
|
usage();
|
||
|
|
|
||
|
|
cap = cap_get_proc();
|
||
|
|
if (cap == NULL) {
|
||
|
|
fprintf(stderr, "cap_get_proc() returned %s!\n",
|
||
|
|
strerror(errno));
|
||
|
|
exit(EXIT_FAILURE);
|
||
|
|
}
|
||
|
|
|
||
|
|
cap_get_flag(cap, CAP_SYS_ADMIN, CAP_EFFECTIVE, &effective);
|
||
|
|
cap_get_flag(cap, CAP_SYS_ADMIN, CAP_PERMITTED, &permitted);
|
||
|
|
if ((effective != CAP_SET) && (permitted != CAP_SET)) {
|
||
|
|
fprintf(stderr, "E: missing 'cap_sys_admin' capability!\n"
|
||
|
|
"Please set it with: setcap cap_sys_admin=ep %s'\n",
|
||
|
|
argv[0]);
|
||
|
|
cap_free(cap);
|
||
|
|
exit(EXIT_FAILURE);
|
||
|
|
}
|
||
|
|
cap_free(cap);
|
||
|
|
|
||
|
|
if ((rv = umount(argv[1])) != 0) {
|
||
|
|
fprintf(stderr, "E: cannot umount %s: %s\n", argv[0],
|
||
|
|
strerror(errno));
|
||
|
|
exit(EXIT_FAILURE);
|
||
|
|
}
|
||
|
|
|
||
|
|
exit(EXIT_SUCCESS);
|
||
|
|
}
|