#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;
/* First, try reading the D-Bus machine id, unless it is a symlink */
fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
if (fd >= 0) {
-
- k = loop_read(fd, id, 32, false);
+ k = loop_read(fd, id, 33, false);
close_nointr_nofail(fd);
- if (k >= 32) {
- id[32] = '\n';
- id[33] = 0;
+ if (k == 33 && id[32] == '\n') {
- log_info("Initializing machine ID from D-Bus machine ID.");
- return 0;
+ id[32] = 0;
+ if (id128_is_valid(id)) {
+ id[32] = '\n';
+ id[33] = 0;
+
+ log_info("Initializing machine ID from D-Bus machine ID.");
+ return 0;
+ }
}
}
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 that didn't work either, see if we are running in a
* container, and a machine ID was passed in via
* $container_uuid the way libvirt/LXC does it */
-
r = detect_container(NULL);
if (r > 0) {
- FILE *f;
-
- f = fopen("/proc/1/environ", "re");
- if (f) {
- bool done = false;
-
- do {
- char line[LINE_MAX];
- unsigned i;
-
- for (i = 0; i < sizeof(line)-1; i++) {
- int c;
-
- c = getc(f);
- if (_unlikely_(c == EOF)) {
- done = true;
- break;
- } else if (c == 0)
- break;
+ _cleanup_free_ char *e = NULL;
- line[i] = c;
- }
- line[i] = 0;
-
- if (startswith(line, "container_uuid=") &&
- strlen(line + 15) >= 36) {
- r = shorten_uuid(id, line + 15);
- if (r >= 0) {
- log_info("Initializing machine ID from container UUID");
- return 0;
- }
+ r = getenv_for_pid(1, "container_uuid", &e);
+ if (r > 0) {
+ if (strlen(e) >= 36) {
+ r = shorten_uuid(id, e);
+ if (r >= 0) {
+ log_info("Initializing machine ID from container UUID.");
+ return 0;
}
-
- } while (!done);
-
- fclose(f);
+ }
}
}
}
int machine_id_setup(void) {
- int fd, r;
- bool writable;
+ _cleanup_close_ int fd = -1;
+ int r;
+ bool writable = false;
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. */
-
- 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;
- }
+ 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;
+ }
- umask(m);
+ writable = false;
+ }
+ }
if (fstat(fd, &st) < 0) {
log_error("fstat() failed: %m");
- r = -errno;
- goto finish;
+ return -errno;
}
- if (S_ISREG(st.st_mode)) {
- if (loop_read(fd, id, 32, false) >= 32) {
- r = 0;
- goto finish;
+ if (S_ISREG(st.st_mode))
+ if (loop_read(fd, id, 33, false) == 33 && id[32] == '\n') {
+ id[32] = 0;
+
+ if (id128_is_valid(id))
+ return 0;
}
- }
/* Hmm, so, the id currently stored is not useful, then let's
* generate one */
r = generate(id);
if (r < 0)
- goto finish;
+ return r;
if (S_ISREG(st.st_mode) && writable) {
lseek(fd, 0, SEEK_SET);
- if (loop_write(fd, id, 33, false) == 33) {
- r = 0;
- goto finish;
- }
+ if (loop_write(fd, id, 33, false) == 33)
+ return 0;
}
close_nointr_nofail(fd);
/* 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));
-
unlink("/run/machine-id");
- goto finish;
+ return 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);
if (r < 0) {
- unlink("/run/machine-id");
- log_error("Failed to mount /etc/machine-id: %s", strerror(-r));
- } else
- log_info("Installed transient /etc/machine-id file.");
+ log_error("Failed to mount /etc/machine-id: %m");
+ unlink_noerrno("/run/machine-id");
+ return -errno;
+ }
-finish:
+ log_info("Installed transient /etc/machine-id file.");
- if (fd >= 0)
- close_nointr_nofail(fd);
+ /* 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: %m");
- return r;
+ return 0;
}
~ianmdlvl / elogind.git / blobdiff