[systemd-commits] .gitignore Makefile.am man/machine-id.xml src/machine-id-main.c src/machine-id-setup.c src/machine-id-setup.h src/main.c
Lennart Poettering
lennart at kemper.freedesktop.org
Fri Mar 4 13:21:12 PST 2011
.gitignore | 1
Makefile.am | 15 ++++
man/machine-id.xml | 104 ++++++++++++++++++++++++++++++
src/machine-id-main.c | 35 ++++++++++
src/machine-id-setup.c | 166 +++++++++++++++++++++++++++++++++++++++++++++++++
src/machine-id-setup.h | 27 +++++++
src/main.c | 2
7 files changed, 349 insertions(+), 1 deletion(-)
New commits:
commit d7ccca2e3f86feb81a48e243d8bad78814659a74
Author: Lennart Poettering <lennart at poettering.net>
Date: Fri Mar 4 21:53:19 2011 +0100
main: introduce /etc/machine-id
This is supposed to play the same roles /var/lib/dbus/machine-id,
however fixes a couple of problems:
- It is available during early boot since it is stored in /etc
- Removes the ID from the D-Bus context and moves it into a system
context, thus hopefully lowering hesitation by people to use it.
- It is generated at installation time. If the file is empty at boot
time it will be mounted over with a randomly generated ID, which is
not saved to disk. This is useful to support state-less machines with
no transient or writable /etc configuration.
diff --git a/.gitignore b/.gitignore
index adee97f..c5bb575 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+systemd-machine-id-setup
systemd-detect-virt
systemd-sysctl
test-strv
diff --git a/Makefile.am b/Makefile.am
index 1841ad5..3d32df2 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -98,7 +98,8 @@ rootbin_PROGRAMS = \
systemd-notify \
systemd-ask-password \
systemd-tty-ask-password-agent \
- systemd-tmpfiles
+ systemd-tmpfiles \
+ systemd-machine-id-setup
bin_PROGRAMS = \
systemd-cgls
@@ -434,6 +435,7 @@ libsystemd_core_la_SOURCES = \
src/loopback-setup.c \
src/kmod-setup.c \
src/locale-setup.c \
+ src/machine-id-setup.c \
src/specifier.c \
src/unit-name.c \
src/fdset.c \
@@ -523,6 +525,7 @@ MANPAGES = \
man/systemd.conf.5 \
man/tmpfiles.d.5 \
man/hostname.5 \
+ man/machine-id.5 \
man/vconsole.conf.5 \
man/locale.conf.5 \
man/os-release.5 \
@@ -737,6 +740,16 @@ systemd_tmpfiles_CFLAGS = \
systemd_tmpfiles_LDADD = \
libsystemd-basic.la
+systemd_machine_id_setup_SOURCES = \
+ src/machine-id-setup.c \
+ src/machine-id-main.c
+
+systemd_machine_id_setup_CFLAGS = \
+ $(AM_CFLAGS)
+
+systemd_machine_id_setup_LDADD = \
+ libsystemd-basic.la
+
systemd_sysctl_SOURCES = \
src/sysctl.c
diff --git a/man/machine-id.xml b/man/machine-id.xml
new file mode 100644
index 0000000..fefeb66
--- /dev/null
+++ b/man/machine-id.xml
@@ -0,0 +1,104 @@
+<?xml version='1.0'?> <!--*-nxml-*-->
+<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="machine-id">
+ <refentryinfo>
+ <title>/etc/machine-id</title>
+ <productname>systemd</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart at poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>machine-id</refentrytitle>
+ <manvolnum>5</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>machine-id</refname>
+ <refpurpose>local machine ID configuration file</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <para><filename>/etc/machine-id</filename></para>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>The <filename>/etc/machine-id</filename> file
+ configures the unique machine id of the local system
+ that is set during installation. It should contain a
+ single newline-terminated, hexadecimal, lowercase 16
+ character machine ID string.</para>
+
+ <para>The machine ID is usually generated from a
+ random source during system installation and stays
+ constant for all subsequent boots. Optionally, for
+ stateless systems it is generated during runtime at
+ boot.</para>
+
+ <para>The machine ID does not change based on user
+ configuration, or when hardware is replaced.</para>
+
+ <para>This machine id follows the same format and
+ logic as the D-Bus machine ID.</para>
+
+ <para>Programs may use this ID to identify the host
+ with a globally unique ID in the network, that does
+ not change even if the local network configuration
+ changes. Due to this and its greater length it is
+ a more useful replacement than the
+ <citerefentry><refentrytitle>gethostid</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call POSIX specifies.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>History</title>
+
+ <para>The simple configuration file format of
+ <filename>/etc/machine-id</filename> originates in the
+ <filename>/var/lib/dbus/machine-id</filename> file
+ introduced by D-Bus. In fact this latter file might be a
+ symlink to the
+ <varname>/etc/machine-id</varname>.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>gethostid</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
diff --git a/src/machine-id-main.c b/src/machine-id-main.c
new file mode 100644
index 0000000..03970a2
--- /dev/null
+++ b/src/machine-id-main.c
@@ -0,0 +1,35 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <unistd.h>
+#include <stdlib.h>
+
+#include "machine-id-setup.h"
+#include "log.h"
+
+int main(int argc, char *argv[]) {
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_parse_environment();
+ log_open();
+
+ return machine_id_setup() < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}
diff --git a/src/machine-id-setup.c b/src/machine-id-setup.c
new file mode 100644
index 0000000..940670b
--- /dev/null
+++ b/src/machine-id-setup.c
@@ -0,0 +1,166 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU 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 <stdlib.h>
+#include <fcntl.h>
+#include <sys/mount.h>
+
+#include "machine-id-setup.h"
+#include "macro.h"
+#include "util.h"
+#include "log.h"
+
+static int generate(char id[34]) {
+ int fd;
+ char buf[16];
+ char *p, *q;
+ ssize_t k;
+
+ assert(id);
+
+ /* First, try reading the D-Bus machine id, unless it is a symlink */
+ if ((fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW)) >= 0) {
+
+ k = loop_read(fd, id, 33, false);
+ close_nointr_nofail(fd);
+
+ if (k >= 32) {
+ id[32] = '\n';
+ id[33] = 0;
+
+ log_info("Initializing machine ID from D-Bus machine ID.");
+ return 0;
+ }
+ }
+
+ /* If that didn't work, generate a random machine id */
+ if ((fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) {
+ log_error("Failed to open /dev/urandom: %m");
+ return -errno;
+ }
+
+ k = loop_read(fd, buf, sizeof(buf), false);
+ close_nointr_nofail(fd);
+
+ if (k != sizeof(buf)) {
+ log_error("Failed to read /dev/urandom: %s", strerror(k < 0 ? -k : EIO));
+ return k < 0 ? (int) k : -EIO;
+ }
+
+ for (p = buf, q = id; p < buf + 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(void) {
+ int fd, r;
+ bool writable;
+ struct stat st;
+ char id[34]; /* 32 + \n + \0 */
+ mode_t m;
+
+ m = umask(0000);
+
+ if ((fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0644)) >= 0)
+ writable = true;
+ else {
+ if ((fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) {
+ umask(m);
+ log_error("Cannot open /etc/machine-id: %m");
+ return -errno;
+ }
+
+ writable = false;
+ }
+
+ umask(m);
+
+ if (fstat(fd, &st) < 0) {
+ log_error("fstat() failed: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ if (S_ISREG(st.st_mode)) {
+ if (loop_read(fd, id, 32, false) >= 32) {
+ r = 0;
+ goto finish;
+ }
+ }
+
+ /* Hmm, so, the id currently stored is not useful, then let's
+ * generate one */
+
+ if ((r = generate(id)) < 0)
+ goto finish;
+
+ if (S_ISREG(st.st_mode) && writable) {
+ lseek(fd, 0, SEEK_SET);
+
+ if (loop_write(fd, id, 33, false) == 33) {
+ r = 0;
+ goto finish;
+ }
+ }
+
+ close_nointr_nofail(fd);
+ fd = -1;
+
+ /* Hmm, we couldn't write it? So let's write it to
+ * /dev/.systemd/machine-id as a replacement */
+
+ mkdir_p("/dev/.systemd", 0755);
+
+ if ((r = write_one_line_file("/dev/.systemd/machine-id", id)) < 0) {
+ log_error("Cannot write /dev/.systemd/machine-id: %s", strerror(-r));
+
+ unlink("/dev/.systemd/machine-id");
+ goto finish;
+ }
+
+ /* And now, let's mount it over */
+ r = mount("/dev/.systemd/machine-id", "/etc/machine-id", "bind", MS_BIND|MS_RDONLY, NULL) < 0 ? -errno : 0;
+ unlink("/dev/.systemd/machine-id");
+
+ if (r < 0)
+ log_error("Failed to mount /etc/machine-id: %s", strerror(-r));
+ else
+ log_info("Installed non-transient /etc/machine-id file.");
+
+finish:
+
+ if (fd >= 0)
+ close_nointr_nofail(fd);
+
+ return r;
+}
diff --git a/src/machine-id-setup.h b/src/machine-id-setup.h
new file mode 100644
index 0000000..4d0a9cf
--- /dev/null
+++ b/src/machine-id-setup.h
@@ -0,0 +1,27 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#ifndef foomachineidsetuphfoo
+#define foomachineidsetuphfoo
+
+/***
+ 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+int machine_id_setup(void);
+
+#endif
diff --git a/src/main.c b/src/main.c
index ef6e681..a041a22 100644
--- a/src/main.c
+++ b/src/main.c
@@ -41,6 +41,7 @@
#include "kmod-setup.h"
#include "locale-setup.h"
#include "selinux-setup.h"
+#include "machine-id-setup.h"
#include "load-fragment.h"
#include "fdset.h"
#include "special.h"
@@ -1127,6 +1128,7 @@ int main(int argc, char *argv[]) {
kmod_setup();
hostname_setup();
+ machine_id_setup();
loopback_setup();
mkdir_p("/dev/.systemd/ask-password/", 0755);
More information about the systemd-commits
mailing list