#include "mkdir.h"
#include "log.h"
#include "virt.h"
+#include "fileio.h"
static int shorten_uuid(char destination[36], const char *source) {
unsigned i, j;
if (k >= 36) {
r = shorten_uuid(id, uuid);
if (r >= 0) {
- log_info("Initializing machine ID from KVM UUID");
+ log_info("Initializing machine ID from KVM UUID.");
return 0;
}
}
if (strlen(e) >= 36) {
r = shorten_uuid(id, e);
if (r >= 0) {
- log_info("Initializing machine ID from container UUID");
+ log_info("Initializing machine ID from container UUID.");
free(e);
return 0;
}
bool writable;
struct stat st;
char id[34]; /* 32 + \n + \0 */
- mode_t m;
- m = umask(0000);
-
- /* We create this 0444, to indicate that this isn't really
- * something you should ever modify. Of course, since the file
- * will be owned by root it doesn't matter much, but maybe
- * people look. */
+ RUN_WITH_UMASK(0000) {
+ /* We create this 0444, to indicate that this isn't really
+ * something you should ever modify. Of course, since the file
+ * will be owned by root it doesn't matter much, but maybe
+ * people look. */
+
+ fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444);
+ if (fd >= 0)
+ writable = true;
+ else {
+ fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (fd < 0) {
+ log_error("Cannot open /etc/machine-id: %m");
+ return -errno;
+ }
- fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444);
- if (fd >= 0)
- writable = true;
- else {
- fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY);
- if (fd < 0) {
- umask(m);
- log_error("Cannot open /etc/machine-id: %m");
- return -errno;
+ writable = false;
}
-
- writable = false;
}
- umask(m);
-
if (fstat(fd, &st) < 0) {
log_error("fstat() failed: %m");
r = -errno;
/* Hmm, we couldn't write it? So let's write it to
* /run/machine-id as a replacement */
- m = umask(0022);
- r = write_one_line_file("/run/machine-id", id);
- umask(m);
-
+ RUN_WITH_UMASK(0022) {
+ r = write_string_file("/run/machine-id", id);
+ }
if (r < 0) {
log_error("Cannot write /run/machine-id: %s", strerror(-r));
}
/* And now, let's mount it over */
- r = mount("/run/machine-id", "/etc/machine-id", "bind", MS_BIND|MS_RDONLY, NULL) < 0 ? -errno : 0;
+ r = mount("/run/machine-id", "/etc/machine-id", NULL, MS_BIND, NULL) < 0 ? -errno : 0;
if (r < 0) {
unlink("/run/machine-id");
log_error("Failed to mount /etc/machine-id: %s", strerror(-r));
- } else
+ } else {
log_info("Installed transient /etc/machine-id file.");
+ /* Mark the mount read-only */
+ if (mount(NULL, "/etc/machine-id", NULL,
+ MS_BIND|MS_RDONLY|MS_REMOUNT, NULL) < 0)
+ log_warning("Failed to make transient /etc/machine-id read-only");
+ }
+
finish:
if (fd >= 0)