/
launch-libvirt.c
1916 lines (1625 loc) · 56.3 KB
/
launch-libvirt.c
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/* libguestfs
* Copyright (C) 2009-2014 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 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdbool.h>
#include <unistd.h>
#include <fcntl.h>
#include <limits.h>
#include <grp.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <assert.h>
#ifdef HAVE_LIBVIRT
#include <libvirt/libvirt.h>
#include <libvirt/virterror.h>
#endif
#include <libxml/xmlIO.h>
#include <libxml/xmlwriter.h>
#include <libxml/xpath.h>
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <libxml/xmlsave.h>
#if HAVE_LIBSELINUX
#include <selinux/selinux.h>
#include <selinux/context.h>
#endif
#include "glthread/lock.h"
#include "guestfs.h"
#include "guestfs-internal.h"
#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
/* Check minimum required version of libvirt. The libvirt backend
* is new and not the default, so we can get away with forcing
* people who want to try it to have a reasonably new version of
* libvirt, so we don't have to work around any bugs in libvirt.
*
* This is also checked at runtime because you can dynamically link
* with a different version from what you were compiled with.
*/
#define MIN_LIBVIRT_MAJOR 0
#define MIN_LIBVIRT_MINOR 10
#define MIN_LIBVIRT_MICRO 2 /* XXX patches in > 2 already */
#define MIN_LIBVIRT_VERSION (MIN_LIBVIRT_MAJOR * 1000000 + \
MIN_LIBVIRT_MINOR * 1000 + \
MIN_LIBVIRT_MICRO)
#if defined(HAVE_LIBVIRT) && \
LIBVIR_VERSION_NUMBER >= MIN_LIBVIRT_VERSION
#ifndef HAVE_XMLBUFFERDETACH
/* Added in libxml2 2.8.0. This is mostly a copy of the function from
* upstream libxml2, which is under a more permissive license.
*/
static xmlChar *
xmlBufferDetach (xmlBufferPtr buf)
{
xmlChar *ret;
if (buf == NULL)
return NULL;
if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE)
return NULL;
ret = buf->content;
buf->content = NULL;
buf->size = 0;
buf->use = 0;
return ret;
}
#endif
#define DOMAIN_NAME_LEN (8+16+1) /* "guestfs-" + random + \0 */
/* Per-handle data. */
struct backend_libvirt_data {
virConnectPtr conn; /* libvirt connection */
virDomainPtr dom; /* libvirt domain */
char *selinux_label;
char *selinux_imagelabel;
bool selinux_norelabel_disks;
char name[DOMAIN_NAME_LEN]; /* random name */
bool is_kvm; /* false = qemu, true = kvm (from capabilities)*/
unsigned long qemu_version; /* qemu version (from libvirt) */
};
/* Parameters passed to construct_libvirt_xml and subfunctions. We
* keep them all in a structure for convenience!
*/
struct libvirt_xml_params {
struct backend_libvirt_data *data;
char *kernel; /* paths to kernel, dtb and initrd */
char *dtb;
char *initrd;
char *appliance_overlay; /* path to qcow2 overlay backed by appliance */
char appliance_dev[64]; /* appliance device name */
size_t appliance_index; /* index of appliance */
char guestfsd_path[UNIX_PATH_MAX]; /* paths to sockets */
char console_path[UNIX_PATH_MAX];
bool enable_svirt; /* false if we decided to disable sVirt */
bool current_proc_is_root; /* true = euid is root */
};
static int parse_capabilities (guestfs_h *g, const char *capabilities_xml, struct backend_libvirt_data *data);
static xmlChar *construct_libvirt_xml (guestfs_h *g, const struct libvirt_xml_params *params);
static void debug_appliance_permissions (guestfs_h *g);
static void debug_socket_permissions (guestfs_h *g);
static void libvirt_error (guestfs_h *g, const char *fs, ...) __attribute__((format (printf,2,3)));
static void libvirt_debug (guestfs_h *g, const char *fs, ...) __attribute__((format (printf,2,3)));
static int is_custom_hv (guestfs_h *g);
static int is_blk (const char *path);
static void ignore_errors (void *ignore, virErrorPtr ignore2);
static void set_socket_create_context (guestfs_h *g);
static void clear_socket_create_context (guestfs_h *g);
#if HAVE_LIBSELINUX
static void selinux_warning (guestfs_h *g, const char *func, const char *selinux_op, const char *data);
#endif
static char *
make_qcow2_overlay (guestfs_h *g, const char *backing_drive,
const char *format)
{
char *overlay;
struct guestfs_disk_create_argv optargs;
if (guestfs___lazy_make_tmpdir (g) == -1)
return NULL;
overlay = safe_asprintf (g, "%s/overlay%d", g->tmpdir, ++g->unique);
optargs.bitmask = GUESTFS_DISK_CREATE_BACKINGFILE_BITMASK;
optargs.backingfile = backing_drive;
if (format) {
optargs.bitmask |= GUESTFS_DISK_CREATE_BACKINGFORMAT_BITMASK;
optargs.backingformat = format;
}
if (guestfs_disk_create_argv (g, overlay, "qcow2", -1, &optargs) == -1) {
free (overlay);
return NULL;
}
return overlay;
}
static char *
create_cow_overlay_libvirt (guestfs_h *g, void *datav, struct drive *drv)
{
#if HAVE_LIBSELINUX
struct backend_libvirt_data *data = datav;
#endif
CLEANUP_FREE char *backing_drive = NULL;
char *overlay;
backing_drive = guestfs___drive_source_qemu_param (g, &drv->src);
if (!backing_drive)
return NULL;
overlay = make_qcow2_overlay (g, backing_drive, drv->src.format);
if (!overlay)
return NULL;
#if HAVE_LIBSELINUX
if (data->selinux_imagelabel) {
debug (g, "setting SELinux label on %s to %s",
overlay, data->selinux_imagelabel);
if (setfilecon (overlay,
(security_context_t) data->selinux_imagelabel) == -1)
selinux_warning (g, __func__, "setfilecon", overlay);
}
#endif
/* Caller sets g->overlay in the handle to this, and then manages
* the memory.
*/
return overlay;
}
static int
launch_libvirt (guestfs_h *g, void *datav, const char *libvirt_uri)
{
struct backend_libvirt_data *data = datav;
int daemon_accept_sock = -1, console_sock = -1;
unsigned long version;
virConnectPtr conn = NULL;
virDomainPtr dom = NULL;
CLEANUP_FREE char *capabilities_xml = NULL;
struct libvirt_xml_params params = {
.data = data,
.kernel = NULL,
.dtb = NULL,
.initrd = NULL,
.appliance_overlay = NULL,
};
CLEANUP_FREE xmlChar *xml = NULL;
CLEANUP_FREE char *appliance = NULL;
struct sockaddr_un addr;
int r;
uint32_t size;
CLEANUP_FREE void *buf = NULL;
params.current_proc_is_root = geteuid () == 0;
/* XXX: It should be possible to make this work. */
if (g->direct_mode) {
error (g, _("direct mode flag is not supported yet for libvirt backend"));
return -1;
}
virGetVersion (&version, NULL, NULL);
debug (g, "libvirt version = %lu (%lu.%lu.%lu)",
version,
version / 1000000UL, version / 1000UL % 1000UL, version % 1000UL);
if (version < MIN_LIBVIRT_VERSION) {
error (g, _("you must have libvirt >= %d.%d.%d "
"to use the 'libvirt' backend"),
MIN_LIBVIRT_MAJOR, MIN_LIBVIRT_MINOR, MIN_LIBVIRT_MICRO);
return -1;
}
guestfs___launch_send_progress (g, 0);
TRACE0 (launch_libvirt_start);
/* Create a random name for the guest. */
memcpy (data->name, "guestfs-", 8);
const size_t random_name_len =
DOMAIN_NAME_LEN - 8 /* "guestfs-" */ - 1 /* \0 */;
if (guestfs___random_string (&data->name[8], random_name_len) == -1) {
perrorf (g, "guestfs___random_string");
return -1;
}
debug (g, "guest random name = %s", data->name);
if (g->verbose)
guestfs___print_timestamped_message (g, "connect to libvirt");
/* Decode the URI string. */
if (!libvirt_uri) { /* "libvirt" */
if (!params.current_proc_is_root)
libvirt_uri = "qemu:///session";
else
libvirt_uri = "qemu:///system";
} else if (STREQ (libvirt_uri, "null")) { /* libvirt:null */
libvirt_uri = NULL;
} /* else nothing */
/* Connect to libvirt, get capabilities. */
conn = guestfs___open_libvirt_connection (g, libvirt_uri, 0);
if (!conn) {
libvirt_error (g, _("could not connect to libvirt (URI = %s)"),
libvirt_uri ? : "NULL");
goto cleanup;
}
/* Suppress default behaviour of printing errors to stderr. Note
* you can't set this to NULL to ignore errors; setting it to NULL
* restores the default error handler ...
*/
virConnSetErrorFunc (conn, NULL, ignore_errors);
/* Get hypervisor (hopefully qemu) version. */
if (virConnectGetVersion (conn, &data->qemu_version) == 0) {
debug (g, "qemu version (reported by libvirt) = %lu (%lu.%lu.%lu)",
data->qemu_version,
data->qemu_version / 1000000UL,
data->qemu_version / 1000UL % 1000UL,
data->qemu_version % 1000UL);
}
else {
libvirt_debug (g, "unable to read qemu version from libvirt");
data->qemu_version = 0;
}
if (g->verbose)
guestfs___print_timestamped_message (g, "get libvirt capabilities");
capabilities_xml = virConnectGetCapabilities (conn);
if (!capabilities_xml) {
libvirt_error (g, _("could not get libvirt capabilities"));
goto cleanup;
}
/* Parse capabilities XML. This fills in various fields in 'params'
* struct, and can also fail if we detect that the hypervisor cannot
* run qemu guests (RHBZ#886915).
*/
if (g->verbose)
guestfs___print_timestamped_message (g, "parsing capabilities XML");
if (parse_capabilities (g, capabilities_xml, data) == -1)
goto cleanup;
/* Misc backend settings. */
guestfs_push_error_handler (g, NULL, NULL);
data->selinux_label =
guestfs_get_backend_setting (g, "internal_libvirt_label");
data->selinux_imagelabel =
guestfs_get_backend_setting (g, "internal_libvirt_imagelabel");
data->selinux_norelabel_disks =
guestfs___get_backend_setting_bool (g, "internal_libvirt_norelabel_disks");
guestfs_pop_error_handler (g);
/* Locate and/or build the appliance. */
TRACE0 (launch_build_libvirt_appliance_start);
if (g->verbose)
guestfs___print_timestamped_message (g, "build appliance");
if (guestfs___build_appliance (g, ¶ms.kernel, ¶ms.dtb,
¶ms.initrd, &appliance) == -1)
goto cleanup;
guestfs___launch_send_progress (g, 3);
TRACE0 (launch_build_libvirt_appliance_end);
/* Note that appliance can be NULL if using the old-style appliance. */
if (appliance) {
params.appliance_overlay = make_qcow2_overlay (g, appliance, "raw");
if (!params.appliance_overlay)
goto cleanup;
}
TRACE0 (launch_build_libvirt_qcow2_overlay_end);
/* Using virtio-serial, we need to create a local Unix domain socket
* for qemu to connect to.
*/
snprintf (params.guestfsd_path, sizeof params.guestfsd_path,
"%s/guestfsd.sock", g->tmpdir);
unlink (params.guestfsd_path);
set_socket_create_context (g);
daemon_accept_sock = socket (AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0);
if (daemon_accept_sock == -1) {
perrorf (g, "socket");
goto cleanup;
}
addr.sun_family = AF_UNIX;
memcpy (addr.sun_path, params.guestfsd_path, UNIX_PATH_MAX);
if (bind (daemon_accept_sock, &addr, sizeof addr) == -1) {
perrorf (g, "bind");
goto cleanup;
}
if (listen (daemon_accept_sock, 1) == -1) {
perrorf (g, "listen");
goto cleanup;
}
/* For the serial console. */
snprintf (params.console_path, sizeof params.console_path,
"%s/console.sock", g->tmpdir);
unlink (params.console_path);
console_sock = socket (AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0);
if (console_sock == -1) {
perrorf (g, "socket");
goto cleanup;
}
addr.sun_family = AF_UNIX;
memcpy (addr.sun_path, params.console_path, UNIX_PATH_MAX);
if (bind (console_sock, &addr, sizeof addr) == -1) {
perrorf (g, "bind");
goto cleanup;
}
if (listen (console_sock, 1) == -1) {
perrorf (g, "listen");
goto cleanup;
}
clear_socket_create_context (g);
/* libvirt, if running as root, will run the qemu process as
* qemu.qemu, which means it won't be able to access the socket.
* There are roughly three things that get in the way:
*
* (1) Permissions of the socket.
*
* (2) Permissions of the parent directory(-ies). Remember this if
* $TMPDIR is located in your home directory.
*
* (3) SELinux/sVirt will prevent access. libvirt ought to label
* the socket.
*
* Note that the 'current_proc_is_root' flag here just means that we
* are root. It's also possible for non-root user to try to use the
* system libvirtd by specifying a qemu:///system URI (RHBZ#913774)
* but there's no sane way to test for that.
*/
if (params.current_proc_is_root) {
/* Current process is root, so try to create sockets that are
* owned by root.qemu with mode 0660 and hence accessible to qemu.
*/
struct group *grp;
if (chmod (params.guestfsd_path, 0660) == -1) {
perrorf (g, "chmod: %s", params.guestfsd_path);
goto cleanup;
}
if (chmod (params.console_path, 0660) == -1) {
perrorf (g, "chmod: %s", params.console_path);
goto cleanup;
}
grp = getgrnam ("qemu");
if (grp != NULL) {
if (chown (params.guestfsd_path, 0, grp->gr_gid) == -1) {
perrorf (g, "chown: %s", params.guestfsd_path);
goto cleanup;
}
if (chown (params.console_path, 0, grp->gr_gid) == -1) {
perrorf (g, "chown: %s", params.console_path);
goto cleanup;
}
} else
debug (g, "cannot find group 'qemu'");
}
/* Construct the libvirt XML. */
if (g->verbose)
guestfs___print_timestamped_message (g, "create libvirt XML");
params.appliance_index = g->nr_drives;
strcpy (params.appliance_dev, "/dev/sd");
guestfs___drive_name (params.appliance_index, ¶ms.appliance_dev[7]);
params.enable_svirt = ! is_custom_hv (g);
xml = construct_libvirt_xml (g, ¶ms);
if (!xml)
goto cleanup;
/* Debug permissions and SELinux contexts on appliance and sockets. */
if (g->verbose) {
debug_appliance_permissions (g);
debug_socket_permissions (g);
}
/* Launch the libvirt guest. */
if (g->verbose)
guestfs___print_timestamped_message (g, "launch libvirt guest");
dom = virDomainCreateXML (conn, (char *) xml, VIR_DOMAIN_START_AUTODESTROY);
if (!dom) {
libvirt_error (g, _(
"could not create appliance through libvirt.\n"
"\n"
"Try running qemu directly without libvirt using this environment variable:\n"
"export LIBGUESTFS_BACKEND=direct\n"
"\n"
"Original error from libvirt"));
goto cleanup;
}
g->state = LAUNCHING;
/* Wait for console socket to be opened (by qemu). */
r = accept4 (console_sock, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
if (r == -1) {
perrorf (g, "accept");
goto cleanup;
}
if (close (console_sock) == -1) {
perrorf (g, "close: console socket");
console_sock = -1;
close (r);
goto cleanup;
}
console_sock = r; /* This is the accepted console socket. */
/* Wait for libvirt domain to start and to connect back to us via
* virtio-serial and send the GUESTFS_LAUNCH_FLAG message.
*/
g->conn =
guestfs___new_conn_socket_listening (g, daemon_accept_sock, console_sock);
if (!g->conn)
goto cleanup;
/* g->conn now owns these sockets. */
daemon_accept_sock = console_sock = -1;
r = g->conn->ops->accept_connection (g, g->conn);
if (r == -1)
goto cleanup;
if (r == 0) {
guestfs___launch_failed_error (g);
goto cleanup;
}
/* NB: We reach here just because qemu has opened the socket. It
* does not mean the daemon is up until we read the
* GUESTFS_LAUNCH_FLAG below. Failures in qemu startup can still
* happen even if we reach here, even early failures like not being
* able to open a drive.
*/
r = guestfs___recv_from_daemon (g, &size, &buf);
if (r == -1) {
guestfs___launch_failed_error (g);
goto cleanup;
}
if (size != GUESTFS_LAUNCH_FLAG) {
guestfs___launch_failed_error (g);
goto cleanup;
}
if (g->verbose)
guestfs___print_timestamped_message (g, "appliance is up");
/* This is possible in some really strange situations, such as
* guestfsd starts up OK but then qemu immediately exits. Check for
* it because the caller is probably expecting to be able to send
* commands after this function returns.
*/
if (g->state != READY) {
error (g, _("qemu launched and contacted daemon, but state != READY"));
goto cleanup;
}
if (appliance)
guestfs___add_dummy_appliance_drive (g);
TRACE0 (launch_libvirt_end);
guestfs___launch_send_progress (g, 12);
data->conn = conn;
data->dom = dom;
free (params.kernel);
free (params.dtb);
free (params.initrd);
free (params.appliance_overlay);
return 0;
cleanup:
clear_socket_create_context (g);
if (console_sock >= 0)
close (console_sock);
if (daemon_accept_sock >= 0)
close (daemon_accept_sock);
if (g->conn) {
g->conn->ops->free_connection (g, g->conn);
g->conn = NULL;
}
if (dom) {
virDomainDestroy (dom);
virDomainFree (dom);
}
if (conn)
virConnectClose (conn);
free (params.kernel);
free (params.dtb);
free (params.initrd);
free (params.appliance_overlay);
g->state = CONFIG;
return -1;
}
static int
parse_capabilities (guestfs_h *g, const char *capabilities_xml,
struct backend_libvirt_data *data)
{
CLEANUP_XMLFREEDOC xmlDocPtr doc = NULL;
CLEANUP_XMLXPATHFREECONTEXT xmlXPathContextPtr xpathCtx = NULL;
CLEANUP_XMLXPATHFREEOBJECT xmlXPathObjectPtr xpathObj = NULL;
size_t i;
xmlNodeSetPtr nodes;
xmlAttrPtr attr;
size_t seen_qemu, seen_kvm;
int force_tcg;
doc = xmlReadMemory (capabilities_xml, strlen (capabilities_xml),
NULL, NULL, XML_PARSE_NONET);
if (doc == NULL) {
error (g, _("unable to parse capabilities XML returned by libvirt"));
return -1;
}
xpathCtx = xmlXPathNewContext (doc);
if (xpathCtx == NULL) {
error (g, _("unable to create new XPath context"));
return -1;
}
/* This gives us a set of all the supported domain types.
* XXX It ignores architecture, but let's not worry about that.
*/
#define XPATH_EXPR "/capabilities/guest/arch/domain/@type"
xpathObj = xmlXPathEvalExpression (BAD_CAST XPATH_EXPR, xpathCtx);
if (xpathObj == NULL) {
error (g, _("unable to evaluate XPath expression: %s"), XPATH_EXPR);
return -1;
}
#undef XPATH_EXPR
nodes = xpathObj->nodesetval;
seen_qemu = seen_kvm = 0;
if (nodes != NULL) {
for (i = 0; i < (size_t) nodes->nodeNr; ++i) {
CLEANUP_FREE char *type = NULL;
if (seen_qemu && seen_kvm)
break;
assert (nodes->nodeTab[i]);
assert (nodes->nodeTab[i]->type == XML_ATTRIBUTE_NODE);
attr = (xmlAttrPtr) nodes->nodeTab[i];
type = (char *) xmlNodeListGetString (doc, attr->children, 1);
if (STREQ (type, "qemu"))
seen_qemu++;
else if (STREQ (type, "kvm"))
seen_kvm++;
}
}
/* This was RHBZ#886915: in that case the default libvirt URI
* pointed to a Xen hypervisor, and so could not create the
* appliance VM.
*/
if (!seen_qemu && !seen_kvm) {
error (g,
_("libvirt hypervisor doesn't support qemu or KVM,\n"
"so we cannot create the libguestfs appliance.\n"
"The current backend is '%s'.\n"
"Check that the PATH environment variable is set and contains\n"
"the path to the qemu ('qemu-system-*') or KVM ('qemu-kvm', 'kvm' etc).\n"
"Or: try setting:\n"
" export LIBGUESTFS_BACKEND=libvirt:qemu:///session\n"
"Or: if you want to have libguestfs run qemu directly, try:\n"
" export LIBGUESTFS_BACKEND=direct\n"
"For further help, read the guestfs(3) man page and libguestfs FAQ."),
guestfs_get_backend (g));
return -1;
}
force_tcg = guestfs___get_backend_setting_bool (g, "force_tcg");
if (force_tcg == -1)
return -1;
if (!force_tcg)
data->is_kvm = seen_kvm;
else
data->is_kvm = 0;
return 0;
}
static int
is_custom_hv (guestfs_h *g)
{
#ifdef QEMU
return g->hv && STRNEQ (g->hv, QEMU);
#else
return 1;
#endif
}
#if HAVE_LIBSELINUX
/* Set sVirt (SELinux) socket create context. For details see:
* https://bugzilla.redhat.com/show_bug.cgi?id=853393#c14
*/
#define SOCKET_CONTEXT "svirt_socket_t"
static void
set_socket_create_context (guestfs_h *g)
{
security_context_t scon; /* this is actually a 'char *' */
context_t con;
if (getcon (&scon) == -1) {
selinux_warning (g, __func__, "getcon", NULL);
return;
}
con = context_new (scon);
if (!con) {
selinux_warning (g, __func__, "context_new", scon);
goto out1;
}
if (context_type_set (con, SOCKET_CONTEXT) == -1) {
selinux_warning (g, __func__, "context_type_set", scon);
goto out2;
}
/* Note that setsockcreatecon sets the per-thread socket creation
* context (/proc/self/task/<tid>/attr/sockcreate) so this is
* thread-safe.
*/
if (setsockcreatecon (context_str (con)) == -1) {
selinux_warning (g, __func__, "setsockcreatecon", context_str (con));
goto out2;
}
out2:
context_free (con);
out1:
freecon (scon);
}
static void
clear_socket_create_context (guestfs_h *g)
{
if (setsockcreatecon (NULL) == -1)
selinux_warning (g, __func__, "setsockcreatecon", "NULL");
}
#else /* !HAVE_LIBSELINUX */
static void
set_socket_create_context (guestfs_h *g)
{
/* nothing */
}
static void
clear_socket_create_context (guestfs_h *g)
{
/* nothing */
}
#endif /* !HAVE_LIBSELINUX */
static void
debug_permissions_cb (guestfs_h *g, void *data, const char *line, size_t len)
{
debug (g, "%s", line);
}
static void
debug_appliance_permissions (guestfs_h *g)
{
CLEANUP_CMD_CLOSE struct command *cmd = guestfs___new_command (g);
CLEANUP_FREE char *cachedir = guestfs_get_cachedir (g);
CLEANUP_FREE char *appliance = NULL;
appliance = safe_asprintf (g, "%s/.guestfs-%d", cachedir, geteuid ());
guestfs___cmd_add_arg (cmd, "ls");
guestfs___cmd_add_arg (cmd, "-a");
guestfs___cmd_add_arg (cmd, "-l");
guestfs___cmd_add_arg (cmd, "-Z");
guestfs___cmd_add_arg (cmd, appliance);
guestfs___cmd_set_stdout_callback (cmd, debug_permissions_cb, NULL, 0);
guestfs___cmd_run (cmd);
}
static void
debug_socket_permissions (guestfs_h *g)
{
if (g->tmpdir) {
CLEANUP_CMD_CLOSE struct command *cmd = guestfs___new_command (g);
guestfs___cmd_add_arg (cmd, "ls");
guestfs___cmd_add_arg (cmd, "-a");
guestfs___cmd_add_arg (cmd, "-l");
guestfs___cmd_add_arg (cmd, "-Z");
guestfs___cmd_add_arg (cmd, g->tmpdir);
guestfs___cmd_set_stdout_callback (cmd, debug_permissions_cb, NULL, 0);
guestfs___cmd_run (cmd);
}
}
static int construct_libvirt_xml_domain (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_name (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_cpu (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_boot (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_seclabel (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_lifecycle (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_devices (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_qemu_cmdline (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
static int construct_libvirt_xml_disk (guestfs_h *g, const struct backend_libvirt_data *data, xmlTextWriterPtr xo, struct drive *drv, size_t drv_index);
static int construct_libvirt_xml_disk_target (guestfs_h *g, xmlTextWriterPtr xo, size_t drv_index);
static int construct_libvirt_xml_disk_driver_qemu (guestfs_h *g, const struct backend_libvirt_data *data, struct drive *drv, xmlTextWriterPtr xo, const char *format, const char *cachemode, enum discard discard);
static int construct_libvirt_xml_disk_address (guestfs_h *g, xmlTextWriterPtr xo, size_t drv_index);
static int construct_libvirt_xml_disk_source_hosts (guestfs_h *g, xmlTextWriterPtr xo, const struct drive_source *src);
static int construct_libvirt_xml_disk_source_seclabel (guestfs_h *g, const struct backend_libvirt_data *data, xmlTextWriterPtr xo);
static int construct_libvirt_xml_appliance (guestfs_h *g, const struct libvirt_xml_params *params, xmlTextWriterPtr xo);
/* These macros make it easier to write XML, but they also make a lot
* of assumptions:
*
* - The xmlTextWriterPtr is called 'xo'. It is used implicitly.
*
* - The guestfs handle is called 'g'. It is used implicitly for errors.
*
* - It is safe to 'return -1' on failure. This is OK provided you
* always use CLEANUP_* macros.
*
* - All the "bad" casting is hidden inside the macros.
*/
/* <element */
#define start_element(element) \
if (xmlTextWriterStartElement (xo, BAD_CAST (element)) == -1) { \
xml_error ("xmlTextWriterStartElement"); \
return -1; \
} \
do
/* finish current </element> */
#define end_element() \
while (0); \
do { \
if (xmlTextWriterEndElement (xo) == -1) { \
xml_error ("xmlTextWriterEndElement"); \
return -1; \
} \
} while (0)
/* <element/> */
#define empty_element(element) start_element(element) {} end_element ()
/* key=value attribute of the current element. */
#define attribute(key,value) \
if (xmlTextWriterWriteAttribute (xo, BAD_CAST (key), BAD_CAST (value)) == -1){\
xml_error ("xmlTextWriterWriteAttribute"); \
return -1; \
}
/* key=value, but value is a printf-style format string. */
#define attribute_format(key,fs,...) \
if (xmlTextWriterWriteFormatAttribute (xo, BAD_CAST (key), \
fs, ##__VA_ARGS__) == -1) { \
xml_error ("xmlTextWriterWriteFormatAttribute"); \
return -1; \
}
/* attribute with namespace. */
#define attribute_ns(prefix,key,namespace_uri,value) \
if (xmlTextWriterWriteAttributeNS (xo, BAD_CAST (prefix), \
BAD_CAST (key), BAD_CAST (namespace_uri), \
BAD_CAST (value)) == -1) { \
xml_error ("xmlTextWriterWriteAttribute"); \
return -1; \
}
/* A string, eg. within an element. */
#define string(str) \
if (xmlTextWriterWriteString (xo, BAD_CAST (str)) == -1) { \
xml_error ("xmlTextWriterWriteString"); \
return -1; \
}
/* A string, using printf-style formatting. */
#define string_format(fs,...) \
if (xmlTextWriterWriteFormatString (xo, fs, ##__VA_ARGS__) == -1) { \
xml_error ("xmlTextWriterWriteFormatString"); \
return -1; \
}
#define xml_error(fn) \
perrorf (g, _("%s:%d: error constructing libvirt XML near call to \"%s\""), \
__FILE__, __LINE__, (fn));
static xmlChar *
construct_libvirt_xml (guestfs_h *g, const struct libvirt_xml_params *params)
{
xmlChar *ret = NULL;
CLEANUP_XMLBUFFERFREE xmlBufferPtr xb = NULL;
xmlOutputBufferPtr ob;
CLEANUP_XMLFREETEXTWRITER xmlTextWriterPtr xo = NULL;
xb = xmlBufferCreate ();
if (xb == NULL) {
perrorf (g, "xmlBufferCreate");
return NULL;
}
ob = xmlOutputBufferCreateBuffer (xb, NULL);
if (ob == NULL) {
perrorf (g, "xmlOutputBufferCreateBuffer");
return NULL;
}
xo = xmlNewTextWriter (ob);
if (xo == NULL) {
perrorf (g, "xmlNewTextWriter");
return NULL;
}
if (xmlTextWriterSetIndent (xo, 1) == -1 ||
xmlTextWriterSetIndentString (xo, BAD_CAST " ") == -1) {
perrorf (g, "could not set XML indent");
return NULL;
}
if (xmlTextWriterStartDocument (xo, NULL, NULL, NULL) == -1) {
perrorf (g, "xmlTextWriterStartDocument");
return NULL;
}
if (construct_libvirt_xml_domain (g, params, xo) == -1)
return NULL;
if (xmlTextWriterEndDocument (xo) == -1) {
perrorf (g, "xmlTextWriterEndDocument");
return NULL;
}
ret = xmlBufferDetach (xb); /* caller frees ret */
if (ret == NULL) {
perrorf (g, "xmlBufferDetach");
return NULL;
}
debug (g, "libvirt XML:\n%s", ret);
return ret;
}
static int
construct_libvirt_xml_domain (guestfs_h *g,
const struct libvirt_xml_params *params,
xmlTextWriterPtr xo)
{
start_element ("domain") {
attribute ("type", params->data->is_kvm ? "kvm" : "qemu");
attribute_ns ("xmlns", "qemu", NULL,
"http://libvirt.org/schemas/domain/qemu/1.0");
if (construct_libvirt_xml_name (g, params, xo) == -1)
return -1;
if (construct_libvirt_xml_cpu (g, params, xo) == -1)
return -1;
if (construct_libvirt_xml_boot (g, params, xo) == -1)
return -1;
if (construct_libvirt_xml_seclabel (g, params, xo) == -1)
return -1;
if (construct_libvirt_xml_lifecycle (g, params, xo) == -1)
return -1;
if (construct_libvirt_xml_devices (g, params, xo) == -1)
return -1;
if (construct_libvirt_xml_qemu_cmdline (g, params, xo) == -1)
return -1;
} end_element ();
return 0;
}
static int
construct_libvirt_xml_name (guestfs_h *g,
const struct libvirt_xml_params *params,
xmlTextWriterPtr xo)
{
start_element ("name") {
string (params->data->name);
} end_element ();
return 0;
}
/* CPU and memory features. */
static int
construct_libvirt_xml_cpu (guestfs_h *g,
const struct libvirt_xml_params *params,
xmlTextWriterPtr xo)