#include <dbus/dbus.h>

#include <errno.h>

#include <string.h>

#include <unistd.h>

#include <dlfcn.h>

#include "util.h"

#include "strv.h"

#include "dbus-common.h"

#include "polkit.h"

#include "def.h"

#include "virt.h"

#define INTERFACE \

" <interface name=\"org.freedesktop.hostname1\">\n" \

" <property name=\"Hostname\" type=\"s\" access=\"read\"/>\n" \

" <property name=\"StaticHostname\" type=\"s\" access=\"read\"/>\n" \

" <property name=\"PrettyHostname\" type=\"s\" access=\"read\"/>\n" \

" <property name=\"IconName\" type=\"s\" access=\"read\"/>\n" \

" <method name=\"SetHostname\">\n" \

" <arg name=\"name\" type=\"s\" direction=\"in\"/>\n" \

" <arg name=\"user_interaction\" type=\"b\" direction=\"in\"/>\n" \

" </method>\n" \

" <method name=\"SetStaticHostname\">\n" \

" <arg name=\"name\" type=\"s\" direction=\"in\"/>\n" \

" <arg name=\"user_interaction\" type=\"b\" direction=\"in\"/>\n" \

" </method>\n" \

" <method name=\"SetPrettyHostname\">\n" \

" <arg name=\"name\" type=\"s\" direction=\"in\"/>\n" \

" <arg name=\"user_interaction\" type=\"b\" direction=\"in\"/>\n" \

" </method>\n" \

" <method name=\"SetIconName\">\n" \

" <arg name=\"name\" type=\"s\" direction=\"in\"/>\n" \

" <arg name=\"user_interaction\" type=\"b\" direction=\"in\"/>\n" \

" </method>\n" \

" </interface>\n"

#define INTROSPECTION \

DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE \

"<node>\n" \

INTERFACE \

BUS_PROPERTIES_INTERFACE \

BUS_INTROSPECTABLE_INTERFACE \

BUS_PEER_INTERFACE \

"</node>\n"

#define INTERFACES_LIST \

BUS_GENERIC_INTERFACES_LIST \

"org.freedesktop.hostname1\0"

const char hostname_interface[] _introspect_("hostname1") = INTERFACE;

enum {

PROP_HOSTNAME,

PROP_STATIC_HOSTNAME,

PROP_PRETTY_HOSTNAME,

PROP_ICON_NAME,

_PROP_MAX

};

static char *data[_PROP_MAX] = {

NULL,

NULL,

NULL,

NULL

};

static usec_t remain_until = 0;

static void free_data(void) {

int p;

for (p = 0; p < _PROP_MAX; p++) {

free(data[p]);

data[p] = NULL;

}

}

static int read_data(void) {

int r;

free_data();

data[PROP_HOSTNAME] = gethostname_malloc();

if (!data[PROP_HOSTNAME])

return -ENOMEM;

r = read_one_line_file("/etc/hostname", &data[PROP_STATIC_HOSTNAME]);

if (r < 0 && r != -ENOENT)

return r;

r = parse_env_file("/etc/machine-info", NEWLINE,

"PRETTY_HOSTNAME", &data[PROP_PRETTY_HOSTNAME],

"ICON_NAME", &data[PROP_ICON_NAME],

NULL);

if (r < 0 && r != -ENOENT)

return r;

return 0;

}

static bool check_nss(void) {

void *dl;

if ((dl = dlopen("libnss_myhostname.so.2", RTLD_LAZY))) {

dlclose(dl);

return true;

}

return false;

}

static const char* fallback_icon_name(void) {

#if defined(__i386__) || defined(__x86_64__)

int r;

char *type;

unsigned t;

#endif

if (detect_virtualization(NULL) > 0)

return "computer-vm";

#if defined(__i386__) || defined(__x86_64__)

r = read_one_line_file("/sys/class/dmi/id/chassis_type", &type);

if (r < 0)

return NULL;

r = safe_atou(type, &t);

free(type);

if (r < 0)

return NULL;

/* We only list the really obvious cases here. The DMI data is

switch (t) {

case 0x3:

case 0x4:

case 0x6:

case 0x7:

return "computer-desktop";

case 0x9:

case 0xA:

case 0xE:

return "computer-laptop";

case 0x11:

case 0x1C:

return "computer-server";

}

#endif

return NULL;

}

static int write_data_hostname(void) {

const char *hn;

if (isempty(data[PROP_HOSTNAME]))

hn = "localhost";

else

hn = data[PROP_HOSTNAME];

if (sethostname(hn, strlen(hn)) < 0)

return -errno;

return 0;

}

static int write_data_static_hostname(void) {

if (isempty(data[PROP_STATIC_HOSTNAME])) {

if (unlink("/etc/hostname") < 0)

return errno == ENOENT ? 0 : -errno;

return 0;

}

return write_one_line_file_atomic("/etc/hostname", data[PROP_STATIC_HOSTNAME]);

}

static int write_data_other(void) {

static const char * const name[_PROP_MAX] = {

[PROP_PRETTY_HOSTNAME] = "PRETTY_HOSTNAME",

[PROP_ICON_NAME] = "ICON_NAME"

};

char **l = NULL;

int r, p;

r = load_env_file("/etc/machine-info", &l);

if (r < 0 && r != -ENOENT)

return r;

for (p = 2; p < _PROP_MAX; p++) {

char *t, **u;

assert(name[p]);

if (isempty(data[p])) {

strv_env_unset(l, name[p]);

continue;

}

if (asprintf(&t, "%s=%s", name[p], strempty(data[p])) < 0) {

strv_free(l);

return -ENOMEM;

}

u = strv_env_set(l, t);

free(t);

strv_free(l);

if (!u)

return -ENOMEM;

l = u;

}

if (strv_isempty(l)) {

if (unlink("/etc/machine-info") < 0)

return errno == ENOENT ? 0 : -errno;

return 0;

}

r = write_env_file("/etc/machine-info", l);

strv_free(l);

return r;

}

static int bus_hostname_append_icon_name(DBusMessageIter *i, const char *property, void *userdata) {

const char *name;

assert(i);

assert(property);

if (isempty(data[PROP_ICON_NAME]))

name = fallback_icon_name();

else

name = data[PROP_ICON_NAME];

return bus_property_append_string(i, property, (void*) name);

}

static const BusProperty bus_hostname_properties[] = {

{ "Hostname", bus_property_append_string, "s", sizeof(data[0])*PROP_HOSTNAME, true },

{ "StaticHostname", bus_property_append_string, "s", sizeof(data[0])*PROP_STATIC_HOSTNAME, true },

{ "PrettyHostname", bus_property_append_string, "s", sizeof(data[0])*PROP_PRETTY_HOSTNAME, true },

{ "IconName", bus_hostname_append_icon_name, "s", sizeof(data[0])*PROP_ICON_NAME, true },

{ NULL, }

};

static const BusBoundProperties bps[] = {

{ "org.freedesktop.hostname1", bus_hostname_properties, data },

{ NULL, }

};

static DBusHandlerResult hostname_message_handler(

DBusConnection *connection,

DBusMessage *message,

void *userdata) {

DBusMessage *reply = NULL, *changed = NULL;

DBusError error;

int r;

assert(connection);

assert(message);

dbus_error_init(&error);

if (dbus_message_is_method_call(message, "org.freedesktop.hostname1", "SetHostname")) {

const char *name;

dbus_bool_t interactive;

if (!dbus_message_get_args(

message,

&error,

DBUS_TYPE_STRING, &name,

DBUS_TYPE_BOOLEAN, &interactive,

DBUS_TYPE_INVALID))

return bus_send_error_reply(connection, message, &error, -EINVAL);

if (isempty(name))

name = data[PROP_STATIC_HOSTNAME];

if (isempty(name))

name = "localhost";

if (!hostname_is_valid(name))

return bus_send_error_reply(connection, message, NULL, -EINVAL);

if (!streq_ptr(name, data[PROP_HOSTNAME])) {

char *h;

r = verify_polkit(connection, message, "org.freedesktop.hostname1.set-hostname", interactive, NULL, &error);

if (r < 0)

return bus_send_error_reply(connection, message, &error, r);

h = strdup(name);

if (!h)

goto oom;

free(data[PROP_HOSTNAME]);

data[PROP_HOSTNAME] = h;

r = write_data_hostname();

if (r < 0) {

log_error("Failed to set host name: %s", strerror(-r));

return bus_send_error_reply(connection, message, NULL, r);

}

log_info("Changed host name to '%s'", strempty(data[PROP_HOSTNAME]));

changed = bus_properties_changed_new(

"/org/freedesktop/hostname1",

"org.freedesktop.hostname1",

"Hostname\0");

if (!changed)

goto oom;

}

} else if (dbus_message_is_method_call(message, "org.freedesktop.hostname1", "SetStaticHostname")) {

const char *name;

dbus_bool_t interactive;

if (!dbus_message_get_args(

message,

&error,

DBUS_TYPE_STRING, &name,

DBUS_TYPE_BOOLEAN, &interactive,

DBUS_TYPE_INVALID))

return bus_send_error_reply(connection, message, &error, -EINVAL);

if (isempty(name))

name = NULL;

if (!streq_ptr(name, data[PROP_STATIC_HOSTNAME])) {

r = verify_polkit(connection, message, "org.freedesktop.hostname1.set-static-hostname", interactive, NULL, &error);

if (r < 0)

return bus_send_error_reply(connection, message, &error, r);

if (isempty(name)) {

free(data[PROP_STATIC_HOSTNAME]);

data[PROP_STATIC_HOSTNAME] = NULL;

} else {

char *h;

if (!hostname_is_valid(name))

return bus_send_error_reply(connection, message, NULL, -EINVAL);

h = strdup(name);

if (!h)

goto oom;

free(data[PROP_STATIC_HOSTNAME]);

data[PROP_STATIC_HOSTNAME] = h;

}

r = write_data_static_hostname();

if (r < 0) {

log_error("Failed to write static host name: %s", strerror(-r));

return bus_send_error_reply(connection, message, NULL, r);

}

log_info("Changed static host name to '%s'", strempty(data[PROP_STATIC_HOSTNAME]));

changed = bus_properties_changed_new(

"/org/freedesktop/hostname1",

"org.freedesktop.hostname1",

"StaticHostname\0");

if (!changed)

goto oom;

}

} else if (dbus_message_is_method_call(message, "org.freedesktop.hostname1", "SetPrettyHostname") ||

dbus_message_is_method_call(message, "org.freedesktop.hostname1", "SetIconName")) {

const char *name;

dbus_bool_t interactive;

int k;

if (!dbus_message_get_args(

message,

&error,

DBUS_TYPE_STRING, &name,

DBUS_TYPE_BOOLEAN, &interactive,

DBUS_TYPE_INVALID))

return bus_send_error_reply(connection, message, &error, -EINVAL);

if (isempty(name))

name = NULL;

k = streq(dbus_message_get_member(message), "SetPrettyHostname") ? PROP_PRETTY_HOSTNAME : PROP_ICON_NAME;

if (!streq_ptr(name, data[k])) {

/* Since the pretty hostname should always be

r = verify_polkit(connection, message, k == PROP_PRETTY_HOSTNAME ?

"org.freedesktop.hostname1.set-static-hostname" :

"org.freedesktop.hostname1.set-machine-info", interactive, NULL, &error);

if (r < 0)

return bus_send_error_reply(connection, message, &error, r);

if (isempty(name)) {

free(data[k]);

data[k] = NULL;

} else {

char *h;

h = strdup(name);

if (!h)

goto oom;

free(data[k]);

data[k] = h;

}

r = write_data_other();

if (r < 0) {

log_error("Failed to write machine info: %s", strerror(-r));

return bus_send_error_reply(connection, message, NULL, r);

}

log_info("Changed %s to '%s'", k == PROP_PRETTY_HOSTNAME ? "pretty host name" : "icon name", strempty(data[k]));

changed = bus_properties_changed_new(

"/org/freedesktop/hostname1",

"org.freedesktop.hostname1",

k == PROP_PRETTY_HOSTNAME ? "PrettyHostname\0" : "IconName\0");

if (!changed)

goto oom;

}

} else

return bus_default_message_handler(connection, message, INTROSPECTION, INTERFACES_LIST, bps);

if (!(reply = dbus_message_new_method_return(message)))

goto oom;

if (!dbus_connection_send(connection, reply, NULL))

goto oom;

dbus_message_unref(reply);

reply = NULL;

if (changed) {

if (!dbus_connection_send(connection, changed, NULL))

goto oom;

dbus_message_unref(changed);

}

return DBUS_HANDLER_RESULT_HANDLED;

oom:

if (reply)

dbus_message_unref(reply);

if (changed)

dbus_message_unref(changed);

dbus_error_free(&error);

return DBUS_HANDLER_RESULT_NEED_MEMORY;

}

static int connect_bus(DBusConnection **_bus) {

static const DBusObjectPathVTable hostname_vtable = {

.message_function = hostname_message_handler

};

DBusError error;

DBusConnection *bus = NULL;

int r;

assert(_bus);

dbus_error_init(&error);

bus = dbus_bus_get_private(DBUS_BUS_SYSTEM, &error);

if (!bus) {

log_error("Failed to get system D-Bus connection: %s", bus_error_message(&error));

r = -ECONNREFUSED;

goto fail;

}

dbus_connection_set_exit_on_disconnect(bus, FALSE);

if (!dbus_connection_register_object_path(bus, "/org/freedesktop/hostname1", &hostname_vtable, NULL) ||

!dbus_connection_add_filter(bus, bus_exit_idle_filter, &remain_until, NULL)) {

log_error("Out of memory.");

r = -ENOMEM;

goto fail;

}

r = dbus_bus_request_name(bus, "org.freedesktop.hostname1", DBUS_NAME_FLAG_DO_NOT_QUEUE, &error);

if (dbus_error_is_set(&error)) {

log_error("Failed to register name on bus: %s", bus_error_message(&error));

r = -EEXIST;

goto fail;

}

if (r != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER) {

log_error("Failed to acquire name.");

r = -EEXIST;

goto fail;

}

if (_bus)

*_bus = bus;

return 0;

fail:

dbus_connection_close(bus);

dbus_connection_unref(bus);

dbus_error_free(&error);

return r;

}

int main(int argc, char *argv[]) {

int r;

DBusConnection *bus = NULL;

bool exiting = false;

log_set_target(LOG_TARGET_AUTO);

log_parse_environment();

log_open();

umask(0022);

if (argc == 2 && streq(argv[1], "--introspect")) {

fputs(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE

"<node>\n", stdout);

fputs(hostname_interface, stdout);

fputs("</node>\n", stdout);

return 0;

}

if (argc != 1) {

log_error("This program takes no arguments.");

r = -EINVAL;

goto finish;

}

if (!check_nss())

log_warning("Warning: nss-myhostname is not installed. Changing the local hostname might make it unresolveable. Please install nss-myhostname!");

r = read_data();

if (r < 0) {

log_error("Failed to read hostname data: %s", strerror(-r));

goto finish;

}

r = connect_bus(&bus);

if (r < 0)

goto finish;

remain_until = now(CLOCK_MONOTONIC) + DEFAULT_EXIT_USEC;

for (;;) {

if (!dbus_connection_read_write_dispatch(bus, exiting ? -1 : (int) (DEFAULT_EXIT_USEC/USEC_PER_MSEC)))

break;

if (!exiting && remain_until < now(CLOCK_MONOTONIC)) {

exiting = true;

bus_async_unregister_and_exit(bus, "org.freedesktop.hostname1");

}

}

r = 0;

finish:

free_data();

if (bus) {

dbus_connection_flush(bus);

dbus_connection_close(bus);

dbus_connection_unref(bus);

}

return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

}