| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <stdlib.h> |
| #include <sys/ioctl.h> |
| #include <sys/resource.h> |
| #include <sys/socket.h> |
| #include <unistd.h> |
| |
| #include "sd-bus.h" |
| #include "sd-daemon.h" |
| #include "sd-event.h" |
| #include "sd-id128.h" |
| |
| #include "bus-common-errors.h" |
| #include "bus-internal.h" |
| #include "bus-label.h" |
| #include "bus-util.h" |
| #include "path-util.h" |
| #include "socket-util.h" |
| #include "stdio-util.h" |
| |
| static int name_owner_change_callback(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) { |
| sd_event *e = userdata; |
| |
| assert(m); |
| assert(e); |
| |
| sd_bus_close(sd_bus_message_get_bus(m)); |
| sd_event_exit(e, 0); |
| |
| return 1; |
| } |
| |
| int bus_async_unregister_and_exit(sd_event *e, sd_bus *bus, const char *name) { |
| const char *match; |
| const char *unique; |
| int r; |
| |
| assert(e); |
| assert(bus); |
| assert(name); |
| |
| /* We unregister the name here and then wait for the |
| * NameOwnerChanged signal for this event to arrive before we |
| * quit. We do this in order to make sure that any queued |
| * requests are still processed before we really exit. */ |
| |
| r = sd_bus_get_unique_name(bus, &unique); |
| if (r < 0) |
| return r; |
| |
| match = strjoina( |
| "sender='org.freedesktop.DBus'," |
| "type='signal'," |
| "interface='org.freedesktop.DBus'," |
| "member='NameOwnerChanged'," |
| "path='/org/freedesktop/DBus'," |
| "arg0='", name, "',", |
| "arg1='", unique, "',", |
| "arg2=''"); |
| |
| r = sd_bus_add_match_async(bus, NULL, match, name_owner_change_callback, NULL, e); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_release_name_async(bus, NULL, name, NULL, NULL); |
| if (r < 0) |
| return r; |
| |
| return 0; |
| } |
| |
| int bus_event_loop_with_idle( |
| sd_event *e, |
| sd_bus *bus, |
| const char *name, |
| usec_t timeout, |
| check_idle_t check_idle, |
| void *userdata) { |
| bool exiting = false; |
| int r, code; |
| |
| assert(e); |
| assert(bus); |
| assert(name); |
| |
| for (;;) { |
| bool idle; |
| |
| r = sd_event_get_state(e); |
| if (r < 0) |
| return r; |
| if (r == SD_EVENT_FINISHED) |
| break; |
| |
| if (check_idle) |
| idle = check_idle(userdata); |
| else |
| idle = true; |
| |
| r = sd_event_run(e, exiting || !idle ? (uint64_t) -1 : timeout); |
| if (r < 0) |
| return r; |
| |
| if (r == 0 && !exiting && idle) { |
| /* Inform the service manager that we are going down, so that it will queue all |
| * further start requests, instead of assuming we are already running. */ |
| sd_notify(false, "STOPPING=1"); |
| |
| r = bus_async_unregister_and_exit(e, bus, name); |
| if (r < 0) |
| return r; |
| |
| exiting = true; |
| continue; |
| } |
| } |
| |
| r = sd_event_get_exit_code(e, &code); |
| if (r < 0) |
| return r; |
| |
| return code; |
| } |
| |
| int bus_name_has_owner(sd_bus *c, const char *name, sd_bus_error *error) { |
| _cleanup_(sd_bus_message_unrefp) sd_bus_message *rep = NULL; |
| int r, has_owner = 0; |
| |
| assert(c); |
| assert(name); |
| |
| r = sd_bus_call_method(c, |
| "org.freedesktop.DBus", |
| "/org/freedesktop/dbus", |
| "org.freedesktop.DBus", |
| "NameHasOwner", |
| error, |
| &rep, |
| "s", |
| name); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_message_read_basic(rep, 'b', &has_owner); |
| if (r < 0) |
| return sd_bus_error_set_errno(error, r); |
| |
| return has_owner; |
| } |
| |
| bool bus_error_is_unknown_service(const sd_bus_error *error) { |
| return sd_bus_error_has_names(error, |
| SD_BUS_ERROR_SERVICE_UNKNOWN, |
| SD_BUS_ERROR_NAME_HAS_NO_OWNER, |
| BUS_ERROR_NO_SUCH_UNIT); |
| } |
| |
| int bus_check_peercred(sd_bus *c) { |
| struct ucred ucred; |
| int fd, r; |
| |
| assert(c); |
| |
| fd = sd_bus_get_fd(c); |
| if (fd < 0) |
| return fd; |
| |
| r = getpeercred(fd, &ucred); |
| if (r < 0) |
| return r; |
| |
| if (ucred.uid != 0 && ucred.uid != geteuid()) |
| return -EPERM; |
| |
| return 1; |
| } |
| |
| int bus_connect_system_systemd(sd_bus **_bus) { |
| _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL; |
| int r; |
| |
| assert(_bus); |
| |
| if (geteuid() != 0) |
| return sd_bus_default_system(_bus); |
| |
| /* If we are root then let's talk directly to the system |
| * instance, instead of going via the bus */ |
| |
| r = sd_bus_new(&bus); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_set_address(bus, "unix:path=/run/systemd/private"); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_start(bus); |
| if (r < 0) |
| return sd_bus_default_system(_bus); |
| |
| r = bus_check_peercred(bus); |
| if (r < 0) |
| return r; |
| |
| *_bus = TAKE_PTR(bus); |
| |
| return 0; |
| } |
| |
| int bus_connect_user_systemd(sd_bus **_bus) { |
| _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL; |
| _cleanup_free_ char *ee = NULL; |
| const char *e; |
| int r; |
| |
| assert(_bus); |
| |
| e = secure_getenv("XDG_RUNTIME_DIR"); |
| if (!e) |
| return sd_bus_default_user(_bus); |
| |
| ee = bus_address_escape(e); |
| if (!ee) |
| return -ENOMEM; |
| |
| r = sd_bus_new(&bus); |
| if (r < 0) |
| return r; |
| |
| bus->address = strjoin("unix:path=", ee, "/systemd/private"); |
| if (!bus->address) |
| return -ENOMEM; |
| |
| r = sd_bus_start(bus); |
| if (r < 0) |
| return sd_bus_default_user(_bus); |
| |
| r = bus_check_peercred(bus); |
| if (r < 0) |
| return r; |
| |
| *_bus = TAKE_PTR(bus); |
| |
| return 0; |
| } |
| |
| int bus_connect_transport(BusTransport transport, const char *host, bool user, sd_bus **ret) { |
| _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL; |
| int r; |
| |
| assert(transport >= 0); |
| assert(transport < _BUS_TRANSPORT_MAX); |
| assert(ret); |
| |
| assert_return((transport == BUS_TRANSPORT_LOCAL) == !host, -EINVAL); |
| assert_return(transport == BUS_TRANSPORT_LOCAL || !user, -EOPNOTSUPP); |
| |
| switch (transport) { |
| |
| case BUS_TRANSPORT_LOCAL: |
| if (user) |
| r = sd_bus_default_user(&bus); |
| else { |
| if (sd_booted() <= 0) |
| /* Print a friendly message when the local system is actually not running systemd as PID 1. */ |
| return log_error_errno(SYNTHETIC_ERRNO(EHOSTDOWN), |
| "System has not been booted with systemd as init system (PID 1). Can't operate."); |
| r = sd_bus_default_system(&bus); |
| } |
| break; |
| |
| case BUS_TRANSPORT_REMOTE: |
| r = sd_bus_open_system_remote(&bus, host); |
| break; |
| |
| case BUS_TRANSPORT_MACHINE: |
| r = sd_bus_open_system_machine(&bus, host); |
| break; |
| |
| default: |
| assert_not_reached("Hmm, unknown transport type."); |
| } |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_set_exit_on_disconnect(bus, true); |
| if (r < 0) |
| return r; |
| |
| *ret = TAKE_PTR(bus); |
| |
| return 0; |
| } |
| |
| int bus_connect_transport_systemd(BusTransport transport, const char *host, bool user, sd_bus **bus) { |
| int r; |
| |
| assert(transport >= 0); |
| assert(transport < _BUS_TRANSPORT_MAX); |
| assert(bus); |
| |
| assert_return((transport == BUS_TRANSPORT_LOCAL) == !host, -EINVAL); |
| assert_return(transport == BUS_TRANSPORT_LOCAL || !user, -EOPNOTSUPP); |
| |
| switch (transport) { |
| |
| case BUS_TRANSPORT_LOCAL: |
| if (user) |
| r = bus_connect_user_systemd(bus); |
| else { |
| if (sd_booted() <= 0) |
| /* Print a friendly message when the local system is actually not running systemd as PID 1. */ |
| return log_error_errno(SYNTHETIC_ERRNO(EHOSTDOWN), |
| "System has not been booted with systemd as init system (PID 1). Can't operate."); |
| r = bus_connect_system_systemd(bus); |
| } |
| break; |
| |
| case BUS_TRANSPORT_REMOTE: |
| r = sd_bus_open_system_remote(bus, host); |
| break; |
| |
| case BUS_TRANSPORT_MACHINE: |
| r = sd_bus_open_system_machine(bus, host); |
| break; |
| |
| default: |
| assert_not_reached("Hmm, unknown transport type."); |
| } |
| |
| return r; |
| } |
| |
| /** |
| * bus_path_encode_unique() - encode unique object path |
| * @b: bus connection or NULL |
| * @prefix: object path prefix |
| * @sender_id: unique-name of client, or NULL |
| * @external_id: external ID to be chosen by client, or NULL |
| * @ret_path: storage for encoded object path pointer |
| * |
| * Whenever we provide a bus API that allows clients to create and manage |
| * server-side objects, we need to provide a unique name for these objects. If |
| * we let the server choose the name, we suffer from a race condition: If a |
| * client creates an object asynchronously, it cannot destroy that object until |
| * it received the method reply. It cannot know the name of the new object, |
| * thus, it cannot destroy it. Furthermore, it enforces a round-trip. |
| * |
| * Therefore, many APIs allow the client to choose the unique name for newly |
| * created objects. There're two problems to solve, though: |
| * 1) Object names are usually defined via dbus object paths, which are |
| * usually globally namespaced. Therefore, multiple clients must be able |
| * to choose unique object names without interference. |
| * 2) If multiple libraries share the same bus connection, they must be |
| * able to choose unique object names without interference. |
| * The first problem is solved easily by prefixing a name with the |
| * unique-bus-name of a connection. The server side must enforce this and |
| * reject any other name. The second problem is solved by providing unique |
| * suffixes from within sd-bus. |
| * |
| * This helper allows clients to create unique object-paths. It uses the |
| * template '/prefix/sender_id/external_id' and returns the new path in |
| * @ret_path (must be freed by the caller). |
| * If @sender_id is NULL, the unique-name of @b is used. If @external_id is |
| * NULL, this function allocates a unique suffix via @b (by requesting a new |
| * cookie). If both @sender_id and @external_id are given, @b can be passed as |
| * NULL. |
| * |
| * Returns: 0 on success, negative error code on failure. |
| */ |
| int bus_path_encode_unique(sd_bus *b, const char *prefix, const char *sender_id, const char *external_id, char **ret_path) { |
| _cleanup_free_ char *sender_label = NULL, *external_label = NULL; |
| char external_buf[DECIMAL_STR_MAX(uint64_t)], *p; |
| int r; |
| |
| assert_return(b || (sender_id && external_id), -EINVAL); |
| assert_return(sd_bus_object_path_is_valid(prefix), -EINVAL); |
| assert_return(ret_path, -EINVAL); |
| |
| if (!sender_id) { |
| r = sd_bus_get_unique_name(b, &sender_id); |
| if (r < 0) |
| return r; |
| } |
| |
| if (!external_id) { |
| xsprintf(external_buf, "%"PRIu64, ++b->cookie); |
| external_id = external_buf; |
| } |
| |
| sender_label = bus_label_escape(sender_id); |
| if (!sender_label) |
| return -ENOMEM; |
| |
| external_label = bus_label_escape(external_id); |
| if (!external_label) |
| return -ENOMEM; |
| |
| p = path_join(prefix, sender_label, external_label); |
| if (!p) |
| return -ENOMEM; |
| |
| *ret_path = p; |
| return 0; |
| } |
| |
| /** |
| * bus_path_decode_unique() - decode unique object path |
| * @path: object path to decode |
| * @prefix: object path prefix |
| * @ret_sender: output parameter for sender-id label |
| * @ret_external: output parameter for external-id label |
| * |
| * This does the reverse of bus_path_encode_unique() (see its description for |
| * details). Both trailing labels, sender-id and external-id, are unescaped and |
| * returned in the given output parameters (the caller must free them). |
| * |
| * Note that this function returns 0 if the path does not match the template |
| * (see bus_path_encode_unique()), 1 if it matched. |
| * |
| * Returns: Negative error code on failure, 0 if the given object path does not |
| * match the template (return parameters are set to NULL), 1 if it was |
| * parsed successfully (return parameters contain allocated labels). |
| */ |
| int bus_path_decode_unique(const char *path, const char *prefix, char **ret_sender, char **ret_external) { |
| const char *p, *q; |
| char *sender, *external; |
| |
| assert(sd_bus_object_path_is_valid(path)); |
| assert(sd_bus_object_path_is_valid(prefix)); |
| assert(ret_sender); |
| assert(ret_external); |
| |
| p = object_path_startswith(path, prefix); |
| if (!p) { |
| *ret_sender = NULL; |
| *ret_external = NULL; |
| return 0; |
| } |
| |
| q = strchr(p, '/'); |
| if (!q) { |
| *ret_sender = NULL; |
| *ret_external = NULL; |
| return 0; |
| } |
| |
| sender = bus_label_unescape_n(p, q - p); |
| external = bus_label_unescape(q + 1); |
| if (!sender || !external) { |
| free(sender); |
| free(external); |
| return -ENOMEM; |
| } |
| |
| *ret_sender = sender; |
| *ret_external = external; |
| return 1; |
| } |
| |
| int bus_track_add_name_many(sd_bus_track *t, char **l) { |
| int r = 0; |
| char **i; |
| |
| assert(t); |
| |
| /* Continues adding after failure, and returns the first failure. */ |
| |
| STRV_FOREACH(i, l) { |
| int k; |
| |
| k = sd_bus_track_add_name(t, *i); |
| if (k < 0 && r >= 0) |
| r = k; |
| } |
| |
| return r; |
| } |
| |
| int bus_open_system_watch_bind_with_description(sd_bus **ret, const char *description) { |
| _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL; |
| const char *e; |
| int r; |
| |
| assert(ret); |
| |
| /* Match like sd_bus_open_system(), but with the "watch_bind" feature and the Connected() signal |
| * turned on. */ |
| |
| r = sd_bus_new(&bus); |
| if (r < 0) |
| return r; |
| |
| if (description) { |
| r = sd_bus_set_description(bus, description); |
| if (r < 0) |
| return r; |
| } |
| |
| e = secure_getenv("DBUS_SYSTEM_BUS_ADDRESS"); |
| if (!e) |
| e = DEFAULT_SYSTEM_BUS_ADDRESS; |
| |
| r = sd_bus_set_address(bus, e); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_set_bus_client(bus, true); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_negotiate_creds(bus, true, SD_BUS_CREDS_UID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_EFFECTIVE_CAPS); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_set_watch_bind(bus, true); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_set_connected_signal(bus, true); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_start(bus); |
| if (r < 0) |
| return r; |
| |
| *ret = TAKE_PTR(bus); |
| |
| return 0; |
| } |
| |
| int bus_reply_pair_array(sd_bus_message *m, char **l) { |
| _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL; |
| char **k, **v; |
| int r; |
| |
| assert(m); |
| |
| /* Reply to the specified message with a message containing a dictionary put together from the |
| * specified strv */ |
| |
| r = sd_bus_message_new_method_return(m, &reply); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_message_open_container(reply, 'a', "{ss}"); |
| if (r < 0) |
| return r; |
| |
| STRV_FOREACH_PAIR(k, v, l) { |
| r = sd_bus_message_append(reply, "{ss}", *k, *v); |
| if (r < 0) |
| return r; |
| } |
| |
| r = sd_bus_message_close_container(reply); |
| if (r < 0) |
| return r; |
| |
| return sd_bus_send(NULL, reply, NULL); |
| } |
| |
| static void bus_message_unref_wrapper(void *m) { |
| sd_bus_message_unref(m); |
| } |
| |
| const struct hash_ops bus_message_hash_ops = { |
| .hash = trivial_hash_func, |
| .compare = trivial_compare_func, |
| .free_value = bus_message_unref_wrapper, |
| }; |