libvirt/src/util/virsystemd.c
Daniel P. Berrangé 568a417224 Enforce a standard header file guard symbol name
Require that all headers are guarded by a symbol named

  LIBVIRT_$FILENAME

where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.

Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-14 10:47:13 +00:00

564 lines
16 KiB
C

/*
* virsystemd.c: helpers for using systemd APIs
*
* Copyright (C) 2013, 2014 Red Hat, Inc.
*
* This library 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.
*
* This library 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 this library. If not, see
* <http://www.gnu.org/licenses/>.
*
*/
#include <config.h>
#include <sys/socket.h>
#ifdef HAVE_SYS_UN_H
# include <sys/un.h>
#endif
#define LIBVIRT_VIRSYSTEMDPRIV_H_ALLOW
#include "virsystemdpriv.h"
#include "virsystemd.h"
#include "viratomic.h"
#include "virbuffer.h"
#include "virdbus.h"
#include "virstring.h"
#include "viralloc.h"
#include "virutil.h"
#include "virlog.h"
#include "virerror.h"
#include "virfile.h"
#define VIR_FROM_THIS VIR_FROM_SYSTEMD
VIR_LOG_INIT("util.systemd");
#ifndef MSG_NOSIGNAL
# define MSG_NOSIGNAL 0
#endif
static void virSystemdEscapeName(virBufferPtr buf,
const char *name)
{
static const char hextable[16] = "0123456789abcdef";
#define ESCAPE(c) \
do { \
virBufferAddChar(buf, '\\'); \
virBufferAddChar(buf, 'x'); \
virBufferAddChar(buf, hextable[(c >> 4) & 15]); \
virBufferAddChar(buf, hextable[c & 15]); \
} while (0)
#define VALID_CHARS \
"0123456789" \
"abcdefghijklmnopqrstuvwxyz" \
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
":-_.\\"
if (*name == '.') {
ESCAPE(*name);
name++;
}
while (*name) {
if (*name == '/')
virBufferAddChar(buf, '-');
else if (*name == '-' ||
*name == '\\' ||
!strchr(VALID_CHARS, *name))
ESCAPE(*name);
else
virBufferAddChar(buf, *name);
name++;
}
#undef ESCAPE
#undef VALID_CHARS
}
char *virSystemdMakeScopeName(const char *name,
const char *drivername,
bool legacy_behaviour)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
virBufferAddLit(&buf, "machine-");
if (legacy_behaviour) {
virSystemdEscapeName(&buf, drivername);
virBufferAddLit(&buf, "\\x2d");
}
virSystemdEscapeName(&buf, name);
virBufferAddLit(&buf, ".scope");
if (virBufferCheckError(&buf) < 0)
return NULL;
return virBufferContentAndReset(&buf);
}
char *virSystemdMakeSliceName(const char *partition)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
if (*partition == '/')
partition++;
virSystemdEscapeName(&buf, partition);
virBufferAddLit(&buf, ".slice");
if (virBufferCheckError(&buf) < 0)
return NULL;
return virBufferContentAndReset(&buf);
}
static int virSystemdHasMachinedCachedValue = -1;
/* Reset the cache from tests for testing the underlying dbus calls
* as well */
void virSystemdHasMachinedResetCachedValue(void)
{
virSystemdHasMachinedCachedValue = -1;
}
/* -2 = machine1 is not supported on this machine
* -1 = error
* 0 = machine1 is available
*/
static int
virSystemdHasMachined(void)
{
int ret;
int val;
val = virAtomicIntGet(&virSystemdHasMachinedCachedValue);
if (val != -1)
return val;
if ((ret = virDBusIsServiceEnabled("org.freedesktop.machine1")) < 0) {
if (ret == -2)
virAtomicIntSet(&virSystemdHasMachinedCachedValue, -2);
return ret;
}
if ((ret = virDBusIsServiceRegistered("org.freedesktop.systemd1")) == -1)
return ret;
virAtomicIntSet(&virSystemdHasMachinedCachedValue, ret);
return ret;
}
char *
virSystemdGetMachineNameByPID(pid_t pid)
{
DBusConnection *conn;
DBusMessage *reply = NULL;
char *name = NULL, *object = NULL;
if (virSystemdHasMachined() < 0)
goto cleanup;
if (!(conn = virDBusGetSystemBus()))
goto cleanup;
if (virDBusCallMethod(conn, &reply, NULL,
"org.freedesktop.machine1",
"/org/freedesktop/machine1",
"org.freedesktop.machine1.Manager",
"GetMachineByPID",
"u", pid) < 0)
goto cleanup;
if (virDBusMessageRead(reply, "o", &object) < 0)
goto cleanup;
virDBusMessageUnref(reply);
reply = NULL;
VIR_DEBUG("Domain with pid %lld has object path '%s'",
(long long) pid, object);
if (virDBusCallMethod(conn, &reply, NULL,
"org.freedesktop.machine1",
object,
"org.freedesktop.DBus.Properties",
"Get",
"ss",
"org.freedesktop.machine1.Machine",
"Name") < 0)
goto cleanup;
if (virDBusMessageRead(reply, "v", "s", &name) < 0)
goto cleanup;
VIR_DEBUG("Domain with pid %lld has machine name '%s'",
(long long) pid, name);
cleanup:
VIR_FREE(object);
virDBusMessageUnref(reply);
return name;
}
/**
* virSystemdCreateMachine:
* @name: driver unique name of the machine
* @drivername: name of the virt driver
* @privileged: whether driver is running privileged or per user
* @uuid: globally unique UUID of the machine
* @rootdir: root directory of machine filesystem
* @pidleader: PID of the leader process
* @iscontainer: true if a container, false if a VM
* @nnicindexes: number of network interface indexes in list
* @nicindexes: list of network interface indexes
* @partition: name of the slice to place the machine in
*
* Returns 0 on success, -1 on fatal error, or -2 if systemd-machine is not available
*/
int virSystemdCreateMachine(const char *name,
const char *drivername,
const unsigned char *uuid,
const char *rootdir,
pid_t pidleader,
bool iscontainer,
size_t nnicindexes,
int *nicindexes,
const char *partition)
{
int ret;
DBusConnection *conn;
char *creatorname = NULL;
char *slicename = NULL;
static int hasCreateWithNetwork = 1;
if ((ret = virSystemdHasMachined()) < 0)
return ret;
if (!(conn = virDBusGetSystemBus()))
return -1;
ret = -1;
if (virAsprintf(&creatorname, "libvirt-%s", drivername) < 0)
goto cleanup;
if (partition) {
if (!(slicename = virSystemdMakeSliceName(partition)))
goto cleanup;
} else {
if (VIR_STRDUP(slicename, "") < 0)
goto cleanup;
}
/*
* The systemd DBus APIs we're invoking have the
* following signature(s)
*
* CreateMachineWithNetwork(in s name,
* in ay id,
* in s service,
* in s class,
* in u leader,
* in s root_directory,
* in ai nicindexes
* in a(sv) scope_properties,
* out o path);
*
* CreateMachine(in s name,
* in ay id,
* in s service,
* in s class,
* in u leader,
* in s root_directory,
* in a(sv) scope_properties,
* out o path);
*
* @name a host unique name for the machine. shows up
* in 'ps' listing & similar
*
* @id: a UUID of the machine, ideally matching /etc/machine-id
* for containers
*
* @service: identifier of the client ie "libvirt-lxc"
*
* @class: either the string "container" or "vm" depending
* on the type of machine
*
* @leader: main PID of the machine, either the host emulator
* process, or the 'init' PID of the container
*
* @root_directory: the root directory of the container, if
* this is known & visible in the host filesystem, or empty string
*
* @nicindexes: list of network interface indexes for the
* host end of the VETH device pairs.
*
* @scope_properties:an array (not a dict!) of properties that are
* passed on to PID 1 when creating a scope unit for your machine.
* Will allow initial settings for the cgroup & similar.
*
* @path: a bus path returned for the machine object created, to
* allow further API calls to be made against the object.
*
*/
VIR_DEBUG("Attempting to create machine via systemd");
if (virAtomicIntGet(&hasCreateWithNetwork)) {
virError error;
memset(&error, 0, sizeof(error));
if (virDBusCallMethod(conn,
NULL,
&error,
"org.freedesktop.machine1",
"/org/freedesktop/machine1",
"org.freedesktop.machine1.Manager",
"CreateMachineWithNetwork",
"sayssusa&ia(sv)",
name,
16,
uuid[0], uuid[1], uuid[2], uuid[3],
uuid[4], uuid[5], uuid[6], uuid[7],
uuid[8], uuid[9], uuid[10], uuid[11],
uuid[12], uuid[13], uuid[14], uuid[15],
creatorname,
iscontainer ? "container" : "vm",
(unsigned int)pidleader,
rootdir ? rootdir : "",
nnicindexes, nicindexes,
3,
"Slice", "s", slicename,
"After", "as", 1, "libvirtd.service",
"Before", "as", 1, "virt-guest-shutdown.target") < 0)
goto cleanup;
if (error.level == VIR_ERR_ERROR) {
if (virDBusErrorIsUnknownMethod(&error)) {
VIR_INFO("CreateMachineWithNetwork isn't supported, switching "
"to legacy CreateMachine method for systemd-machined");
virResetError(&error);
virAtomicIntSet(&hasCreateWithNetwork, 0);
/* Could re-structure without Using goto, but this
* avoids another atomic read which would trigger
* another memory barrier */
goto fallback;
}
virReportErrorObject(&error);
virResetError(&error);
goto cleanup;
}
} else {
fallback:
if (virDBusCallMethod(conn,
NULL,
NULL,
"org.freedesktop.machine1",
"/org/freedesktop/machine1",
"org.freedesktop.machine1.Manager",
"CreateMachine",
"sayssusa(sv)",
name,
16,
uuid[0], uuid[1], uuid[2], uuid[3],
uuid[4], uuid[5], uuid[6], uuid[7],
uuid[8], uuid[9], uuid[10], uuid[11],
uuid[12], uuid[13], uuid[14], uuid[15],
creatorname,
iscontainer ? "container" : "vm",
(unsigned int)pidleader,
rootdir ? rootdir : "",
3,
"Slice", "s", slicename,
"After", "as", 1, "libvirtd.service",
"Before", "as", 1, "virt-guest-shutdown.target") < 0)
goto cleanup;
}
ret = 0;
cleanup:
VIR_FREE(creatorname);
VIR_FREE(slicename);
return ret;
}
int virSystemdTerminateMachine(const char *name)
{
int ret;
DBusConnection *conn;
virError error;
if (!name)
return 0;
memset(&error, 0, sizeof(error));
if ((ret = virSystemdHasMachined()) < 0)
goto cleanup;
ret = -1;
if (!(conn = virDBusGetSystemBus()))
goto cleanup;
/*
* The systemd DBus API we're invoking has the
* following signature
*
* TerminateMachine(in s name);
*
* @name a host unique name for the machine. shows up
* in 'ps' listing & similar
*/
VIR_DEBUG("Attempting to terminate machine via systemd");
if (virDBusCallMethod(conn,
NULL,
&error,
"org.freedesktop.machine1",
"/org/freedesktop/machine1",
"org.freedesktop.machine1.Manager",
"TerminateMachine",
"s",
name) < 0)
goto cleanup;
if (error.level == VIR_ERR_ERROR &&
STRNEQ_NULLABLE("org.freedesktop.machine1.NoSuchMachine",
error.str1)) {
virReportErrorObject(&error);
goto cleanup;
}
ret = 0;
cleanup:
virResetError(&error);
return ret;
}
void
virSystemdNotifyStartup(void)
{
#ifdef HAVE_SYS_UN_H
const char *path;
const char *msg = "READY=1";
int fd;
struct sockaddr_un un = {
.sun_family = AF_UNIX,
};
struct iovec iov = {
.iov_base = (char *)msg,
.iov_len = strlen(msg),
};
struct msghdr mh = {
.msg_name = &un,
.msg_iov = &iov,
.msg_iovlen = 1,
};
if (!(path = virGetEnvBlockSUID("NOTIFY_SOCKET"))) {
VIR_DEBUG("Skipping systemd notify, not requested");
return;
}
/* NB sun_path field is *not* NUL-terminated, hence >, not >= */
if (strlen(path) > sizeof(un.sun_path)) {
VIR_WARN("Systemd notify socket path '%s' too long", path);
return;
}
memcpy(un.sun_path, path, strlen(path));
if (un.sun_path[0] == '@')
un.sun_path[0] = '\0';
mh.msg_namelen = offsetof(struct sockaddr_un, sun_path) + strlen(path);
fd = socket(AF_UNIX, SOCK_DGRAM, 0);
if (fd < 0) {
VIR_WARN("Unable to create socket FD");
return;
}
if (sendmsg(fd, &mh, MSG_NOSIGNAL) < 0)
VIR_WARN("Failed to notify systemd");
VIR_FORCE_CLOSE(fd);
#endif /* HAVE_SYS_UN_H */
}
static int
virSystemdPMSupportTarget(const char *methodName, bool *result)
{
int ret;
DBusConnection *conn;
DBusMessage *message = NULL;
char *response;
ret = virDBusIsServiceEnabled("org.freedesktop.login1");
if (ret < 0)
return ret;
if ((ret = virDBusIsServiceRegistered("org.freedesktop.login1")) < 0)
return ret;
if (!(conn = virDBusGetSystemBus()))
return -1;
ret = -1;
if (virDBusCallMethod(conn,
&message,
NULL,
"org.freedesktop.login1",
"/org/freedesktop/login1",
"org.freedesktop.login1.Manager",
methodName,
NULL) < 0)
return ret;
if ((ret = virDBusMessageRead(message, "s", &response)) < 0)
goto cleanup;
*result = STREQ("yes", response) || STREQ("challenge", response);
ret = 0;
cleanup:
virDBusMessageUnref(message);
VIR_FREE(response);
return ret;
}
int virSystemdCanSuspend(bool *result)
{
return virSystemdPMSupportTarget("CanSuspend", result);
}
int virSystemdCanHibernate(bool *result)
{
return virSystemdPMSupportTarget("CanHibernate", result);
}
int virSystemdCanHybridSleep(bool *result)
{
return virSystemdPMSupportTarget("CanHybridSleep", result);
}