diff options
Diffstat (limited to 'src/hostname')
| -rw-r--r-- | src/hostname/hostnamed.c | 623 |
1 files changed, 623 insertions, 0 deletions
diff --git a/src/hostname/hostnamed.c b/src/hostname/hostnamed.c new file mode 100644 index 0000000000..f3b2c94173 --- /dev/null +++ b/src/hostname/hostnamed.c @@ -0,0 +1,623 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2011 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 <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 + unreliable enough, so let's not do any additional guesswork + on top of that. + + See the SMBIOS Specification 2.7.1 section 7.4.1 for + details about the values listed here: + + http://www.dmtf.org/sites/default/files/standards/documents/DSP0134_2.7.1.pdf + */ + + 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 DBusHandlerResult hostname_message_handler( + DBusConnection *connection, + DBusMessage *message, + void *userdata) { + + const BusProperty properties[] = { + { "org.freedesktop.hostname1", "Hostname", bus_property_append_string, "s", data[PROP_HOSTNAME]}, + { "org.freedesktop.hostname1", "StaticHostname", bus_property_append_string, "s", data[PROP_STATIC_HOSTNAME]}, + { "org.freedesktop.hostname1", "PrettyHostname", bus_property_append_string, "s", data[PROP_PRETTY_HOSTNAME]}, + { "org.freedesktop.hostname1", "IconName", bus_hostname_append_icon_name, "s", data[PROP_ICON_NAME]}, + { NULL, NULL, NULL, NULL, NULL } + }; + + 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, &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, &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 + * changed at the same time as the static one, + * use the same policy action for both... */ + + r = verify_polkit(connection, message, k == PROP_PRETTY_HOSTNAME ? + "org.freedesktop.hostname1.set-static-hostname" : + "org.freedesktop.hostname1.set-machine-info", interactive, &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, properties); + + 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("Not enough 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; +} |