summaryrefslogtreecommitdiff
path: root/src/core/machine-id-setup.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/core/machine-id-setup.c')
-rw-r--r--src/core/machine-id-setup.c361
1 files changed, 0 insertions, 361 deletions
diff --git a/src/core/machine-id-setup.c b/src/core/machine-id-setup.c
deleted file mode 100644
index 7505dcbcaa..0000000000
--- a/src/core/machine-id-setup.c
+++ /dev/null
@@ -1,361 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <unistd.h>
-#include <stdio.h>
-#include <errno.h>
-#include <string.h>
-#include <fcntl.h>
-#include <sys/mount.h>
-
-#include "systemd/sd-id128.h"
-
-#include "machine-id-setup.h"
-#include "macro.h"
-#include "util.h"
-#include "mkdir.h"
-#include "log.h"
-#include "virt.h"
-#include "fileio.h"
-#include "path-util.h"
-
-static int shorten_uuid(char destination[34], const char source[36]) {
- unsigned i, j;
-
- assert(destination);
- assert(source);
-
- /* Converts a UUID into a machine ID, by lowercasing it and
- * removing dashes. Validates everything. */
-
- for (i = 0, j = 0; i < 36 && j < 32; i++) {
- int t;
-
- t = unhexchar(source[i]);
- if (t < 0)
- continue;
-
- destination[j++] = hexchar(t);
- }
-
- if (i != 36 || j != 32)
- return -EINVAL;
-
- destination[32] = '\n';
- destination[33] = 0;
- return 0;
-}
-
-static int read_machine_id(int fd, char id[34]) {
- char id_to_validate[34];
- int r;
-
- assert(fd >= 0);
- assert(id);
-
- /* Reads a machine ID from a file, validates it, and returns
- * it. The returned ID ends in a newline. */
-
- r = loop_read_exact(fd, id_to_validate, 33, false);
- if (r < 0)
- return r;
-
- if (id_to_validate[32] != '\n')
- return -EINVAL;
-
- id_to_validate[32] = 0;
-
- if (!id128_is_valid(id_to_validate))
- return -EINVAL;
-
- memcpy(id, id_to_validate, 32);
- id[32] = '\n';
- id[33] = 0;
- return 0;
-}
-
-static int write_machine_id(int fd, char id[34]) {
- assert(fd >= 0);
- assert(id);
-
- if (lseek(fd, 0, SEEK_SET) < 0)
- return -errno;
-
- return loop_write(fd, id, 33, false);
-}
-
-static int generate_machine_id(char id[34], const char *root) {
- int fd, r;
- unsigned char *p;
- sd_id128_t buf;
- char *q;
- const char *vm_id, *dbus_machine_id;
-
- assert(id);
-
- if (isempty(root))
- dbus_machine_id = "/var/lib/dbus/machine-id";
- else
- dbus_machine_id = strjoina(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 (fd >= 0) {
- r = read_machine_id(fd, id);
- safe_close(fd);
-
- if (r >= 0) {
- log_info("Initializing machine ID from D-Bus machine ID.");
- return 0;
- }
- }
-
- 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) {
- _cleanup_free_ char *e = NULL;
-
- r = getenv_for_pid(1, "container_uuid", &e);
- if (r > 0) {
- r = shorten_uuid(id, e);
- if (r >= 0) {
- 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[36];
-
- fd = open("/sys/class/dmi/id/product_uuid", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
- if (fd >= 0) {
- r = loop_read_exact(fd, uuid, 36, false);
- safe_close(fd);
-
- if (r >= 0) {
- r = shorten_uuid(id, uuid);
- if (r >= 0) {
- log_info("Initializing machine ID from KVM UUID.");
- return 0;
- }
- }
- }
- }
- }
- }
-
- /* If that didn't work, generate a random machine id */
- r = sd_id128_randomize(&buf);
- if (r < 0)
- return log_error_errno(r, "Failed to open /dev/urandom: %m");
-
- for (p = buf.bytes, q = id; p < buf.bytes + sizeof(buf); p++, q += 2) {
- q[0] = hexchar(*p >> 4);
- q[1] = hexchar(*p & 15);
- }
-
- id[32] = '\n';
- id[33] = 0;
-
- log_info("Initializing machine ID from random generator.");
-
- return 0;
-}
-
-int machine_id_setup(const char *root) {
- const char *etc_machine_id, *run_machine_id;
- _cleanup_close_ int fd = -1;
- bool writable = true;
- char id[34]; /* 32 + \n + \0 */
- int r;
-
- if (isempty(root)) {
- etc_machine_id = "/etc/machine-id";
- run_machine_id = "/run/machine-id";
- } else {
- char *x;
-
- x = strjoina(root, "/etc/machine-id");
- etc_machine_id = path_kill_slashes(x);
-
- x = strjoina(root, "/run/machine-id");
- run_machine_id = path_kill_slashes(x);
- }
-
- 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. */
-
- mkdir_parents(etc_machine_id, 0755);
- fd = open(etc_machine_id, O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444);
- if (fd < 0) {
- int old_errno = errno;
-
- fd = open(etc_machine_id, O_RDONLY|O_CLOEXEC|O_NOCTTY);
- if (fd < 0) {
- if (old_errno == EROFS && errno == ENOENT)
- log_error_errno(errno,
- "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_errno(errno, "Cannot open %s: %m", etc_machine_id);
-
- return -errno;
- }
-
- writable = false;
- }
- }
-
- if (read_machine_id(fd, id) >= 0)
- return 0;
-
- /* Hmm, so, the id currently stored is not useful, then let's
- * generate one */
-
- r = generate_machine_id(id, root);
- if (r < 0)
- return r;
-
- if (writable)
- if (write_machine_id(fd, id) >= 0)
- return 0;
-
- fd = safe_close(fd);
-
- /* Hmm, we couldn't write it? So let's write it to
- * /run/machine-id as a replacement */
-
- RUN_WITH_UMASK(0022) {
- r = write_string_file(run_machine_id, id);
- }
- if (r < 0) {
- (void) unlink(run_machine_id);
- return log_error_errno(r, "Cannot write %s: %m", run_machine_id);
- }
-
- /* And now, let's mount it over */
- if (mount(run_machine_id, etc_machine_id, NULL, MS_BIND, NULL) < 0) {
- (void) unlink_noerrno(run_machine_id);
- return log_error_errno(errno, "Failed to mount %s: %m", etc_machine_id);
- }
-
- log_info("Installed transient %s file.", etc_machine_id);
-
- /* Mark the mount read-only */
- if (mount(NULL, etc_machine_id, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, NULL) < 0)
- log_warning_errno(errno, "Failed to make transient %s read-only: %m", etc_machine_id);
-
- return 0;
-}
-
-int machine_id_commit(const char *root) {
- _cleanup_close_ int fd = -1, initial_mntns_fd = -1;
- const char *etc_machine_id;
- char id[34]; /* 32 + \n + \0 */
- int r;
-
- if (isempty(root))
- etc_machine_id = "/etc/machine-id";
- else {
- char *x;
-
- x = strjoina(root, "/etc/machine-id");
- etc_machine_id = path_kill_slashes(x);
- }
-
- r = path_is_mount_point(etc_machine_id, false);
- if (r < 0)
- return log_error_errno(r, "Failed to determine whether %s is a mount point: %m", etc_machine_id);
- if (r == 0) {
- log_debug("%s is is not a mount point. Nothing to do.", etc_machine_id);
- return 0;
- }
-
- /* Read existing machine-id */
- fd = open(etc_machine_id, O_RDONLY|O_CLOEXEC|O_NOCTTY);
- if (fd < 0)
- return log_error_errno(errno, "Cannot open %s: %m", etc_machine_id);
-
- r = read_machine_id(fd, id);
- if (r < 0)
- return log_error_errno(r, "We didn't find a valid machine ID in %s.", etc_machine_id);
-
- r = is_fd_on_temporary_fs(fd);
- if (r < 0)
- return log_error_errno(r, "Failed to determine whether %s is on a temporary file system: %m", etc_machine_id);
- if (r == 0) {
- log_error("%s is not on a temporary file system.", etc_machine_id);
- return -EROFS;
- }
-
- fd = safe_close(fd);
-
- /* Store current mount namespace */
- r = namespace_open(0, NULL, &initial_mntns_fd, NULL, NULL);
- if (r < 0)
- return log_error_errno(r, "Can't fetch current mount namespace: %m");
-
- /* Switch to a new mount namespace, isolate ourself and unmount etc_machine_id in our new namespace */
- if (unshare(CLONE_NEWNS) < 0)
- return log_error_errno(errno, "Failed to enter new namespace: %m");
-
- if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL) < 0)
- return log_error_errno(errno, "Couldn't make-rslave / mountpoint in our private namespace: %m");
-
- if (umount(etc_machine_id) < 0)
- return log_error_errno(errno, "Failed to unmount transient %s file in our private namespace: %m", etc_machine_id);
-
- /* Update a persistent version of etc_machine_id */
- fd = open(etc_machine_id, O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444);
- if (fd < 0)
- return log_error_errno(errno, "Cannot open for writing %s. This is mandatory to get a persistent machine-id: %m", etc_machine_id);
-
- r = write_machine_id(fd, id);
- if (r < 0)
- return log_error_errno(r, "Cannot write %s: %m", etc_machine_id);
-
- fd = safe_close(fd);
-
- /* Return to initial namespace and proceed a lazy tmpfs unmount */
- r = namespace_enter(-1, initial_mntns_fd, -1, -1);
- if (r < 0)
- return log_warning_errno(r, "Failed to switch back to initial mount namespace: %m.\nWe'll keep transient %s file until next reboot.", etc_machine_id);
-
- if (umount2(etc_machine_id, MNT_DETACH) < 0)
- return log_warning_errno(errno, "Failed to unmount transient %s file: %m.\nWe keep that mount until next reboot.", etc_machine_id);
-
- return 0;
-}