#include <fcntl.h>
#include <sys/mount.h>
-#include <systemd/sd-id128.h>
+#include "systemd/sd-id128.h"
#include "machine-id-setup.h"
#include "macro.h"
#include "fileio.h"
#include "path-util.h"
-static int shorten_uuid(char destination[36], const char *source) {
+static int shorten_uuid(char destination[34], const char source[36]) {
unsigned i, j;
for (i = 0, j = 0; i < 36 && j < 32; i++) {
int fd, r;
unsigned char *p;
sd_id128_t buf;
- char *q;
+ char *q;
ssize_t k;
- const char *vm_id;
- _cleanup_free_ char *dbus_machine_id = NULL;
+ const char *vm_id, *dbus_machine_id;
assert(id);
- if (asprintf(&dbus_machine_id, "%s/var/lib/dbus/machine-id", root) < 0)
- return log_oom();
+ if (isempty(root))
+ dbus_machine_id = "/var/lib/dbus/machine-id";
+ else
+ dbus_machine_id = strappenda(root, "/var/lib/dbus/machine-id");
/* First, try reading the D-Bus machine id, unless it is a symlink */
fd = open(dbus_machine_id, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
}
}
- /* If that didn't work, 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) {
- _cleanup_free_ char *e = NULL;
-
- r = getenv_for_pid(1, "container_uuid", &e);
+ if (isempty(root)) {
+ /* If that didn't work, 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) {
- if (strlen(e) >= 36) {
- r = shorten_uuid(id, e);
- if (r >= 0) {
- log_info("Initializing machine ID from container UUID.");
- return 0;
- }
- }
- }
+ _cleanup_free_ char *e = NULL;
- } else {
- /* If we are not running in a container, see if we are
- * running in qemu/kvm and a machine ID was passed in
- * via -uuid on the qemu/kvm command line */
-
- r = detect_vm(&vm_id);
- if (r > 0 && streq(vm_id, "kvm")) {
- char uuid[37];
-
- fd = open("/sys/class/dmi/id/product_uuid", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd >= 0) {
- k = loop_read(fd, uuid, 36, false);
- safe_close(fd);
-
- if (k >= 36) {
- r = shorten_uuid(id, uuid);
+ 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 KVM UUID.");
+ log_info("Initializing machine ID from container UUID.");
return 0;
}
}
}
+
+ } else {
+ /* If we are not running in a container, see if we are
+ * running in qemu/kvm and a machine ID was passed in
+ * via -uuid on the qemu/kvm command line */
+
+ r = detect_vm(&vm_id);
+ if (r > 0 && streq(vm_id, "kvm")) {
+ char uuid[37];
+
+ fd = open("/sys/class/dmi/id/product_uuid", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
+ if (fd >= 0) {
+ k = loop_read(fd, uuid, 36, false);
+ safe_close(fd);
+
+ if (k >= 36) {
+ r = shorten_uuid(id, uuid);
+ if (r >= 0) {
+ log_info("Initializing machine ID from KVM UUID.");
+ return 0;
+ }
+ }
+ }
+ }
}
}
}
int machine_id_setup(const char *root) {
+ const char *etc_machine_id, *run_machine_id;
_cleanup_close_ int fd = -1;
- int r;
- bool writable = false;
+ bool writable = true;
struct stat st;
char id[34]; /* 32 + \n + \0 */
- char *etc_machine_id, *run_machine_id;
+ int r;
- etc_machine_id = strappenda(root, "/etc/machine-id");
- path_kill_slashes(etc_machine_id);
+ if (isempty(root)) {
+ etc_machine_id = "/etc/machine-id";
+ run_machine_id = "/run/machine-id";
+ } else {
+ etc_machine_id = strappenda(root, "/etc/machine-id");
+ path_kill_slashes((char*) etc_machine_id);
- run_machine_id = strappenda(root, "/run/machine-id");
- path_kill_slashes(run_machine_id);
+ run_machine_id = strappenda(root, "/run/machine-id");
+ path_kill_slashes((char*) run_machine_id);
+ }
RUN_WITH_UMASK(0000) {
/* We create this 0444, to indicate that this isn't really
* will be owned by root it doesn't matter much, but maybe
* people look. */
+ mkdir_parents(etc_machine_id, 0755);
fd = open(etc_machine_id, O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444);
- if (fd >= 0)
- writable = true;
- else {
+ if (fd < 0) {
+ int old_errno = errno;
+
fd = open(etc_machine_id, O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0) {
- log_error("Cannot open %s: %m", etc_machine_id);
+ if (old_errno == EROFS && errno == ENOENT)
+ log_error("System cannot boot: Missing /etc/machine-id and /etc is mounted read-only.\n"
+ "Booting up is supported only when:\n"
+ "1) /etc/machine-id exists and is populated.\n"
+ "2) /etc/machine-id exists and is empty.\n"
+ "3) /etc/machine-id is missing and /etc is writable.\n");
+ else
+ log_error("Cannot open %s: %m", etc_machine_id);
return -errno;
}