diff options
Diffstat (limited to 'src/libsystemd/sd-bus/sd-bus.c')
| -rw-r--r-- | src/libsystemd/sd-bus/sd-bus.c | 4441 |
1 files changed, 4441 insertions, 0 deletions
diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c new file mode 100644 index 0000000..8befc97 --- /dev/null +++ b/src/libsystemd/sd-bus/sd-bus.c @@ -0,0 +1,4441 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <endian.h> +#include <netdb.h> +#include <pthread.h> +#include <signal.h> +#include <stdlib.h> +#include <sys/mman.h> +#include <sys/stat.h> +#include <sys/wait.h> +#include <unistd.h> + +#include "sd-bus.h" + +#include "af-list.h" +#include "alloc-util.h" +#include "bus-container.h" +#include "bus-control.h" +#include "bus-internal.h" +#include "bus-kernel.h" +#include "bus-label.h" +#include "bus-message.h" +#include "bus-objects.h" +#include "bus-protocol.h" +#include "bus-slot.h" +#include "bus-socket.h" +#include "bus-track.h" +#include "bus-type.h" +#include "cgroup-util.h" +#include "constants.h" +#include "errno-util.h" +#include "fd-util.h" +#include "glyph-util.h" +#include "hexdecoct.h" +#include "hostname-util.h" +#include "io-util.h" +#include "macro.h" +#include "memory-util.h" +#include "missing_syscall.h" +#include "missing_threads.h" +#include "origin-id.h" +#include "parse-util.h" +#include "path-util.h" +#include "process-util.h" +#include "stdio-util.h" +#include "string-util.h" +#include "strv.h" +#include "user-util.h" + +#define log_debug_bus_message(m) \ + do { \ + sd_bus_message *_mm = (m); \ + log_debug("Got message type=%s sender=%s destination=%s path=%s interface=%s member=%s " \ + " cookie=%" PRIu64 " reply_cookie=%" PRIu64 \ + " signature=%s error-name=%s error-message=%s", \ + strna(bus_message_type_to_string(_mm->header->type)), \ + strna(sd_bus_message_get_sender(_mm)), \ + strna(sd_bus_message_get_destination(_mm)), \ + strna(sd_bus_message_get_path(_mm)), \ + strna(sd_bus_message_get_interface(_mm)), \ + strna(sd_bus_message_get_member(_mm)), \ + BUS_MESSAGE_COOKIE(_mm), \ + _mm->reply_cookie, \ + strna(_mm->root_container.signature), \ + strna(_mm->error.name), \ + strna(_mm->error.message)); \ + } while (false) + +static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec); +static void bus_detach_io_events(sd_bus *b); + +static thread_local sd_bus *default_system_bus = NULL; +static thread_local sd_bus *default_user_bus = NULL; +static thread_local sd_bus *default_starter_bus = NULL; + +static sd_bus **bus_choose_default(int (**bus_open)(sd_bus **)) { + const char *e; + + /* Let's try our best to reuse another cached connection. If + * the starter bus type is set, connect via our normal + * connection logic, ignoring $DBUS_STARTER_ADDRESS, so that + * we can share the connection with the user/system default + * bus. */ + + e = secure_getenv("DBUS_STARTER_BUS_TYPE"); + if (e) { + if (streq(e, "system")) { + if (bus_open) + *bus_open = sd_bus_open_system; + return &default_system_bus; + } else if (STR_IN_SET(e, "user", "session")) { + if (bus_open) + *bus_open = sd_bus_open_user; + return &default_user_bus; + } + } + + /* No type is specified, so we have not other option than to + * use the starter address if it is set. */ + e = secure_getenv("DBUS_STARTER_ADDRESS"); + if (e) { + if (bus_open) + *bus_open = sd_bus_open; + return &default_starter_bus; + } + + /* Finally, if nothing is set use the cached connection for + * the right scope */ + + if (cg_pid_get_owner_uid(0, NULL) >= 0) { + if (bus_open) + *bus_open = sd_bus_open_user; + return &default_user_bus; + } else { + if (bus_open) + *bus_open = sd_bus_open_system; + return &default_system_bus; + } +} + +sd_bus *bus_resolve(sd_bus *bus) { + switch ((uintptr_t) bus) { + case (uintptr_t) SD_BUS_DEFAULT: + return *(bus_choose_default(NULL)); + case (uintptr_t) SD_BUS_DEFAULT_USER: + return default_user_bus; + case (uintptr_t) SD_BUS_DEFAULT_SYSTEM: + return default_system_bus; + default: + return bus; + } +} + +void bus_close_io_fds(sd_bus *b) { + assert(b); + + bus_detach_io_events(b); + + if (b->input_fd != b->output_fd) + safe_close(b->output_fd); + b->output_fd = b->input_fd = safe_close(b->input_fd); +} + +void bus_close_inotify_fd(sd_bus *b) { + assert(b); + + b->inotify_event_source = sd_event_source_disable_unref(b->inotify_event_source); + + b->inotify_fd = safe_close(b->inotify_fd); + b->inotify_watches = mfree(b->inotify_watches); + b->n_inotify_watches = 0; +} + +static void bus_reset_queues(sd_bus *b) { + assert(b); + + while (b->rqueue_size > 0) + bus_message_unref_queued(b->rqueue[--b->rqueue_size], b); + + b->rqueue = mfree(b->rqueue); + + while (b->wqueue_size > 0) + bus_message_unref_queued(b->wqueue[--b->wqueue_size], b); + + b->wqueue = mfree(b->wqueue); +} + +static sd_bus* bus_free(sd_bus *b) { + sd_bus_slot *s; + + assert(b); + assert(!b->track_queue); + assert(!b->tracks); + + b->state = BUS_CLOSED; + + sd_bus_detach_event(b); + + while ((s = b->slots)) { + /* At this point only floating slots can still be + * around, because the non-floating ones keep a + * reference to the bus, and we thus couldn't be + * destructing right now... We forcibly disconnect the + * slots here, so that they still can be referenced by + * apps, but are dead. */ + + assert(s->floating); + bus_slot_disconnect(s, true); + } + + if (b->default_bus_ptr) + *b->default_bus_ptr = NULL; + + bus_close_io_fds(b); + bus_close_inotify_fd(b); + + free(b->label); + free(b->groups); + free(b->rbuffer); + free(b->unique_name); + free(b->auth_buffer); + free(b->address); + free(b->machine); + free(b->description); + free(b->patch_sender); + + free(b->exec_path); + strv_free(b->exec_argv); + + close_many(b->fds, b->n_fds); + free(b->fds); + + bus_reset_queues(b); + + ordered_hashmap_free_free(b->reply_callbacks); + prioq_free(b->reply_callbacks_prioq); + + assert(b->match_callbacks.type == BUS_MATCH_ROOT); + bus_match_free(&b->match_callbacks); + + hashmap_free_free(b->vtable_methods); + hashmap_free_free(b->vtable_properties); + + assert(hashmap_isempty(b->nodes)); + hashmap_free(b->nodes); + + bus_flush_memfd(b); + + assert_se(pthread_mutex_destroy(&b->memfd_cache_mutex) == 0); + + return mfree(b); +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(sd_bus*, bus_free); + +DEFINE_ORIGIN_ID_HELPERS(sd_bus, bus); + +_public_ int sd_bus_new(sd_bus **ret) { + _cleanup_free_ sd_bus *b = NULL; + + assert_return(ret, -EINVAL); + + b = new(sd_bus, 1); + if (!b) + return -ENOMEM; + + *b = (sd_bus) { + .n_ref = 1, + .input_fd = -EBADF, + .output_fd = -EBADF, + .inotify_fd = -EBADF, + .message_version = 1, + .creds_mask = SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_UNIQUE_NAME, + .accept_fd = true, + .origin_id = origin_id_query(), + .n_groups = SIZE_MAX, + .close_on_exit = true, + .ucred = UCRED_INVALID, + .runtime_scope = _RUNTIME_SCOPE_INVALID, + }; + + /* We guarantee that wqueue always has space for at least one entry */ + if (!GREEDY_REALLOC(b->wqueue, 1)) + return -ENOMEM; + + assert_se(pthread_mutex_init(&b->memfd_cache_mutex, NULL) == 0); + + *ret = TAKE_PTR(b); + return 0; +} + +_public_ int sd_bus_set_address(sd_bus *bus, const char *address) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(address, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return free_and_strdup(&bus->address, address); +} + +_public_ int sd_bus_set_fd(sd_bus *bus, int input_fd, int output_fd) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(input_fd >= 0, -EBADF); + assert_return(output_fd >= 0, -EBADF); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->input_fd = input_fd; + bus->output_fd = output_fd; + return 0; +} + +_public_ int sd_bus_set_exec(sd_bus *bus, const char *path, char *const *argv) { + _cleanup_strv_free_ char **a = NULL; + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(path, -EINVAL); + assert_return(!strv_isempty(argv), -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + a = strv_copy(argv); + if (!a) + return -ENOMEM; + + r = free_and_strdup(&bus->exec_path, path); + if (r < 0) + return r; + + return strv_free_and_replace(bus->exec_argv, a); +} + +_public_ int sd_bus_set_bus_client(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus->patch_sender, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->bus_client = !!b; + return 0; +} + +_public_ int sd_bus_set_monitor(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->is_monitor = !!b; + return 0; +} + +_public_ int sd_bus_negotiate_fds(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->accept_fd = !!b; + return 0; +} + +_public_ int sd_bus_negotiate_timestamp(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!IN_SET(bus->state, BUS_CLOSING, BUS_CLOSED), -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + /* This is not actually supported by any of our transports these days, but we do honour it for synthetic + * replies, and maybe one day classic D-Bus learns this too */ + bus->attach_timestamp = !!b; + + return 0; +} + +_public_ int sd_bus_negotiate_creds(sd_bus *bus, int b, uint64_t mask) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(mask <= _SD_BUS_CREDS_ALL, -EINVAL); + assert_return(!IN_SET(bus->state, BUS_CLOSING, BUS_CLOSED), -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + SET_FLAG(bus->creds_mask, mask, b); + + /* The well knowns we need unconditionally, so that matches can work */ + bus->creds_mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_UNIQUE_NAME; + + return 0; +} + +_public_ int sd_bus_set_server(sd_bus *bus, int b, sd_id128_t server_id) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(b || sd_id128_equal(server_id, SD_ID128_NULL), -EINVAL); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->is_server = !!b; + bus->server_id = server_id; + return 0; +} + +_public_ int sd_bus_set_anonymous(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->anonymous_auth = !!b; + return 0; +} + +_public_ int sd_bus_set_trusted(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->trusted = !!b; + return 0; +} + +_public_ int sd_bus_set_description(sd_bus *bus, const char *description) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return free_and_strdup(&bus->description, description); +} + +_public_ int sd_bus_set_allow_interactive_authorization(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->allow_interactive_authorization = !!b; + return 0; +} + +_public_ int sd_bus_get_allow_interactive_authorization(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->allow_interactive_authorization; +} + +_public_ int sd_bus_set_watch_bind(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->watch_bind = !!b; + return 0; +} + +_public_ int sd_bus_get_watch_bind(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->watch_bind; +} + +_public_ int sd_bus_set_connected_signal(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus->connected_signal = !!b; + return 0; +} + +_public_ int sd_bus_get_connected_signal(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->connected_signal; +} + +static int synthesize_connected_signal(sd_bus *bus) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; + int r; + + assert(bus); + + /* If enabled, synthesizes a local "Connected" signal mirroring the local "Disconnected" signal. This is called + * whenever we fully established a connection, i.e. after the authorization phase, and after receiving the + * Hello() reply. Or in other words, whenever we enter BUS_RUNNING state. + * + * This is useful so that clients can start doing stuff whenever the connection is fully established in a way + * that works independently from whether we connected to a full bus or just a direct connection. */ + + if (!bus->connected_signal) + return 0; + + r = sd_bus_message_new_signal( + bus, + &m, + "/org/freedesktop/DBus/Local", + "org.freedesktop.DBus.Local", + "Connected"); + if (r < 0) + return r; + + bus_message_set_sender_local(bus, m); + m->read_counter = ++bus->read_counter; + + r = bus_seal_synthetic_message(bus, m); + if (r < 0) + return r; + + r = bus_rqueue_make_room(bus); + if (r < 0) + return r; + + /* Insert at the very front */ + memmove(bus->rqueue + 1, bus->rqueue, sizeof(sd_bus_message*) * bus->rqueue_size); + bus->rqueue[0] = bus_message_ref_queued(m, bus); + bus->rqueue_size++; + + return 0; +} + +void bus_set_state(sd_bus *bus, enum bus_state state) { + static const char* const table[_BUS_STATE_MAX] = { + [BUS_UNSET] = "UNSET", + [BUS_WATCH_BIND] = "WATCH_BIND", + [BUS_OPENING] = "OPENING", + [BUS_AUTHENTICATING] = "AUTHENTICATING", + [BUS_HELLO] = "HELLO", + [BUS_RUNNING] = "RUNNING", + [BUS_CLOSING] = "CLOSING", + [BUS_CLOSED] = "CLOSED", + }; + + assert(bus); + assert(state < _BUS_STATE_MAX); + + if (state == bus->state) + return; + + log_debug("Bus %s: changing state %s %s %s", strna(bus->description), + table[bus->state], special_glyph(SPECIAL_GLYPH_ARROW_RIGHT), table[state]); + bus->state = state; +} + +static int hello_callback(sd_bus_message *reply, void *userdata, sd_bus_error *error) { + const char *s; + sd_bus *bus; + int r; + + assert(reply); + bus = reply->bus; + assert(bus); + assert(IN_SET(bus->state, BUS_HELLO, BUS_CLOSING)); + + r = sd_bus_message_get_errno(reply); + if (r > 0) { + r = -r; + goto fail; + } + + r = sd_bus_message_read(reply, "s", &s); + if (r < 0) + goto fail; + + if (!service_name_is_valid(s) || s[0] != ':') { + r = -EBADMSG; + goto fail; + } + + r = free_and_strdup(&bus->unique_name, s); + if (r < 0) + goto fail; + + if (bus->state == BUS_HELLO) { + bus_set_state(bus, BUS_RUNNING); + + r = synthesize_connected_signal(bus); + if (r < 0) + goto fail; + } + + return 1; + +fail: + /* When Hello() failed, let's propagate this in two ways: first we return the error immediately here, + * which is the propagated up towards the event loop. Let's also invalidate the connection, so that + * if the user then calls back into us again we won't wait any longer. */ + + bus_set_state(bus, BUS_CLOSING); + return r; +} + +static int bus_send_hello(sd_bus *bus) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; + int r; + + assert(bus); + + if (!bus->bus_client) + return 0; + + r = sd_bus_message_new_method_call( + bus, + &m, + "org.freedesktop.DBus", + "/org/freedesktop/DBus", + "org.freedesktop.DBus", + "Hello"); + if (r < 0) + return r; + + return sd_bus_call_async(bus, NULL, m, hello_callback, NULL, 0); +} + +int bus_start_running(sd_bus *bus) { + struct reply_callback *c; + usec_t n; + int r; + + assert(bus); + assert(bus->state < BUS_HELLO); + + /* We start all method call timeouts when we enter BUS_HELLO or BUS_RUNNING mode. At this point let's convert + * all relative to absolute timestamps. Note that we do not reshuffle the reply callback priority queue since + * adding a fixed value to all entries should not alter the internal order. */ + + n = now(CLOCK_MONOTONIC); + ORDERED_HASHMAP_FOREACH(c, bus->reply_callbacks) { + if (c->timeout_usec == 0) + continue; + + c->timeout_usec = usec_add(n, c->timeout_usec); + } + + if (bus->bus_client) { + bus_set_state(bus, BUS_HELLO); + return 1; + } + + bus_set_state(bus, BUS_RUNNING); + + r = synthesize_connected_signal(bus); + if (r < 0) + return r; + + return 1; +} + +static int parse_address_key(const char **p, const char *key, char **value) { + _cleanup_free_ char *r = NULL; + size_t l, n = 0; + const char *a; + + assert(p); + assert(*p); + assert(value); + + if (key) { + l = strlen(key); + if (strncmp(*p, key, l) != 0) + return 0; + + if ((*p)[l] != '=') + return 0; + + if (*value) + return -EINVAL; + + a = *p + l + 1; + } else + a = *p; + + while (!IN_SET(*a, ';', ',', 0)) { + char c; + + if (*a == '%') { + int x, y; + + x = unhexchar(a[1]); + if (x < 0) + return x; + + y = unhexchar(a[2]); + if (y < 0) + return y; + + c = (char) ((x << 4) | y); + a += 3; + } else { + c = *a; + a++; + } + + if (!GREEDY_REALLOC(r, n + 2)) + return -ENOMEM; + + r[n++] = c; + } + + if (!r) { + r = strdup(""); + if (!r) + return -ENOMEM; + } else + r[n] = 0; + + if (*a == ',') + a++; + + *p = a; + + free_and_replace(*value, r); + + return 1; +} + +static void skip_address_key(const char **p) { + assert(p); + assert(*p); + + *p += strcspn(*p, ","); + + if (**p == ',') + (*p)++; +} + +static int parse_unix_address(sd_bus *b, const char **p, char **guid) { + _cleanup_free_ char *path = NULL, *abstract = NULL; + size_t l; + int r; + + assert(b); + assert(p); + assert(*p); + assert(guid); + + while (!IN_SET(**p, 0, ';')) { + r = parse_address_key(p, "guid", guid); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "path", &path); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "abstract", &abstract); + if (r < 0) + return r; + else if (r > 0) + continue; + + skip_address_key(p); + } + + if (!path && !abstract) + return -EINVAL; + + if (path && abstract) + return -EINVAL; + + if (path) { + l = strlen(path); + if (l >= sizeof(b->sockaddr.un.sun_path)) /* We insist on NUL termination */ + return -E2BIG; + + b->sockaddr.un = (struct sockaddr_un) { + .sun_family = AF_UNIX, + }; + + memcpy(b->sockaddr.un.sun_path, path, l); + b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + l + 1; + + } else { + assert(abstract); + + l = strlen(abstract); + if (l >= sizeof(b->sockaddr.un.sun_path) - 1) /* We insist on NUL termination */ + return -E2BIG; + + b->sockaddr.un = (struct sockaddr_un) { + .sun_family = AF_UNIX, + }; + + memcpy(b->sockaddr.un.sun_path+1, abstract, l); + b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + 1 + l; + } + + b->is_local = true; + + return 0; +} + +static int parse_tcp_address(sd_bus *b, const char **p, char **guid) { + _cleanup_free_ char *host = NULL, *port = NULL, *family = NULL; + int r; + struct addrinfo *result, hints = { + .ai_socktype = SOCK_STREAM, + }; + + assert(b); + assert(p); + assert(*p); + assert(guid); + + while (!IN_SET(**p, 0, ';')) { + r = parse_address_key(p, "guid", guid); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "host", &host); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "port", &port); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "family", &family); + if (r < 0) + return r; + else if (r > 0) + continue; + + skip_address_key(p); + } + + if (!host || !port) + return -EINVAL; + + if (family) { + hints.ai_family = af_from_ipv4_ipv6(family); + if (hints.ai_family == AF_UNSPEC) + return -EINVAL; + } + + r = getaddrinfo(host, port, &hints, &result); + if (r == EAI_SYSTEM) + return -errno; + else if (r != 0) + return -EADDRNOTAVAIL; + + memcpy(&b->sockaddr, result->ai_addr, result->ai_addrlen); + b->sockaddr_size = result->ai_addrlen; + + freeaddrinfo(result); + + b->is_local = false; + + return 0; +} + +static int parse_exec_address(sd_bus *b, const char **p, char **guid) { + char *path = NULL; + unsigned n_argv = 0, j; + char **argv = NULL; + int r; + + assert(b); + assert(p); + assert(*p); + assert(guid); + + while (!IN_SET(**p, 0, ';')) { + r = parse_address_key(p, "guid", guid); + if (r < 0) + goto fail; + else if (r > 0) + continue; + + r = parse_address_key(p, "path", &path); + if (r < 0) + goto fail; + else if (r > 0) + continue; + + if (startswith(*p, "argv")) { + unsigned ul; + + errno = 0; + ul = strtoul(*p + 4, (char**) p, 10); + if (errno > 0 || **p != '=' || ul > 256) { + r = -EINVAL; + goto fail; + } + + (*p)++; + + if (ul >= n_argv) { + if (!GREEDY_REALLOC0(argv, ul + 2)) { + r = -ENOMEM; + goto fail; + } + + n_argv = ul + 1; + } + + r = parse_address_key(p, NULL, argv + ul); + if (r < 0) + goto fail; + + continue; + } + + skip_address_key(p); + } + + if (!path) { + r = -EINVAL; + goto fail; + } + + /* Make sure there are no holes in the array, with the + * exception of argv[0] */ + for (j = 1; j < n_argv; j++) + if (!argv[j]) { + r = -EINVAL; + goto fail; + } + + if (argv && argv[0] == NULL) { + argv[0] = strdup(path); + if (!argv[0]) { + r = -ENOMEM; + goto fail; + } + } + + b->exec_path = path; + b->exec_argv = argv; + + b->is_local = false; + + return 0; + +fail: + for (j = 0; j < n_argv; j++) + free(argv[j]); + + free(argv); + free(path); + return r; +} + +static int parse_container_unix_address(sd_bus *b, const char **p, char **guid) { + _cleanup_free_ char *machine = NULL, *pid = NULL; + int r; + + assert(b); + assert(p); + assert(*p); + assert(guid); + + while (!IN_SET(**p, 0, ';')) { + r = parse_address_key(p, "guid", guid); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "machine", &machine); + if (r < 0) + return r; + else if (r > 0) + continue; + + r = parse_address_key(p, "pid", &pid); + if (r < 0) + return r; + else if (r > 0) + continue; + + skip_address_key(p); + } + + if (!machine == !pid) + return -EINVAL; + + if (machine) { + if (!hostname_is_valid(machine, VALID_HOSTNAME_DOT_HOST)) + return -EINVAL; + + free_and_replace(b->machine, machine); + } else + b->machine = mfree(b->machine); + + if (pid) { + r = parse_pid(pid, &b->nspid); + if (r < 0) + return r; + } else + b->nspid = 0; + + b->sockaddr.un = (struct sockaddr_un) { + .sun_family = AF_UNIX, + /* Note that we use the old /var/run prefix here, to increase compatibility with really old containers */ + .sun_path = "/var/run/dbus/system_bus_socket", + }; + b->sockaddr_size = SOCKADDR_UN_LEN(b->sockaddr.un); + b->is_local = false; + + return 0; +} + +static void bus_reset_parsed_address(sd_bus *b) { + assert(b); + + zero(b->sockaddr); + b->sockaddr_size = 0; + b->exec_argv = strv_free(b->exec_argv); + b->exec_path = mfree(b->exec_path); + b->server_id = SD_ID128_NULL; + b->machine = mfree(b->machine); + b->nspid = 0; +} + +static int bus_parse_next_address(sd_bus *b) { + _cleanup_free_ char *guid = NULL; + const char *a; + int r; + + assert(b); + + if (!b->address) + return 0; + if (b->address[b->address_index] == 0) + return 0; + + bus_reset_parsed_address(b); + + a = b->address + b->address_index; + + while (*a != 0) { + + if (*a == ';') { + a++; + continue; + } + + if (startswith(a, "unix:")) { + a += 5; + + r = parse_unix_address(b, &a, &guid); + if (r < 0) + return r; + break; + + } else if (startswith(a, "tcp:")) { + + a += 4; + r = parse_tcp_address(b, &a, &guid); + if (r < 0) + return r; + + break; + + } else if (startswith(a, "unixexec:")) { + + a += 9; + r = parse_exec_address(b, &a, &guid); + if (r < 0) + return r; + + break; + + } else if (startswith(a, "x-machine-unix:")) { + + a += 15; + r = parse_container_unix_address(b, &a, &guid); + if (r < 0) + return r; + + break; + } + + a = strchr(a, ';'); + if (!a) + return 0; + } + + if (guid) { + r = sd_id128_from_string(guid, &b->server_id); + if (r < 0) + return r; + } + + b->address_index = a - b->address; + return 1; +} + +static void bus_kill_exec(sd_bus *bus) { + if (!pid_is_valid(bus->busexec_pid)) + return; + + sigterm_wait(TAKE_PID(bus->busexec_pid)); +} + +static int bus_start_address(sd_bus *b) { + int r; + + assert(b); + + for (;;) { + bus_close_io_fds(b); + bus_close_inotify_fd(b); + + bus_kill_exec(b); + + /* If you provide multiple different bus-addresses, we + * try all of them in order and use the first one that + * succeeds. */ + + if (b->exec_path) + r = bus_socket_exec(b); + else if ((b->nspid > 0 || b->machine) && b->sockaddr.sa.sa_family != AF_UNSPEC) + r = bus_container_connect_socket(b); + else if (b->sockaddr.sa.sa_family != AF_UNSPEC) + r = bus_socket_connect(b); + else + goto next; + + if (r >= 0) { + int q; + + q = bus_attach_io_events(b); + if (q < 0) + return q; + + q = bus_attach_inotify_event(b); + if (q < 0) + return q; + + return r; + } + + b->last_connect_error = -r; + + next: + r = bus_parse_next_address(b); + if (r < 0) + return r; + if (r == 0) + return b->last_connect_error > 0 ? -b->last_connect_error : -ECONNREFUSED; + } +} + +int bus_next_address(sd_bus *b) { + assert(b); + + bus_reset_parsed_address(b); + return bus_start_address(b); +} + +static int bus_start_fd(sd_bus *b) { + struct stat st; + int r; + + assert(b); + assert(b->input_fd >= 0); + assert(b->output_fd >= 0); + + if (DEBUG_LOGGING) { + _cleanup_free_ char *pi = NULL, *po = NULL; + (void) fd_get_path(b->input_fd, &pi); + (void) fd_get_path(b->output_fd, &po); + log_debug("sd-bus: starting bus%s%s on fds %d/%d (%s, %s)...", + b->description ? " " : "", strempty(b->description), + b->input_fd, b->output_fd, + pi ?: "???", po ?: "???"); + } + + r = fd_nonblock(b->input_fd, true); + if (r < 0) + return r; + + r = fd_cloexec(b->input_fd, true); + if (r < 0) + return r; + + if (b->input_fd != b->output_fd) { + r = fd_nonblock(b->output_fd, true); + if (r < 0) + return r; + + r = fd_cloexec(b->output_fd, true); + if (r < 0) + return r; + } + + if (fstat(b->input_fd, &st) < 0) + return -errno; + + return bus_socket_take_fd(b); +} + +_public_ int sd_bus_start(sd_bus *bus) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state == BUS_UNSET, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + bus_set_state(bus, BUS_OPENING); + + if (bus->is_server && bus->bus_client) + return -EINVAL; + + if (bus->input_fd >= 0) + r = bus_start_fd(bus); + else if (bus->address || bus->sockaddr.sa.sa_family != AF_UNSPEC || bus->exec_path || bus->machine) + r = bus_start_address(bus); + else + return -EINVAL; + + if (r < 0) { + sd_bus_close(bus); + return r; + } + + return bus_send_hello(bus); +} + +_public_ int sd_bus_open_with_description(sd_bus **ret, const char *description) { + const char *e; + _cleanup_(bus_freep) sd_bus *b = NULL; + int r; + + assert_return(ret, -EINVAL); + + /* Let's connect to the starter bus if it is set, and + * otherwise to the bus that is appropriate for the scope + * we are running in */ + + e = secure_getenv("DBUS_STARTER_BUS_TYPE"); + if (e) { + if (streq(e, "system")) + return sd_bus_open_system_with_description(ret, description); + else if (STR_IN_SET(e, "session", "user")) + return sd_bus_open_user_with_description(ret, description); + } + + e = secure_getenv("DBUS_STARTER_ADDRESS"); + if (!e) { + if (cg_pid_get_owner_uid(0, NULL) >= 0) + return sd_bus_open_user_with_description(ret, description); + else + return sd_bus_open_system_with_description(ret, description); + } + + r = sd_bus_new(&b); + if (r < 0) + return r; + + r = sd_bus_set_address(b, e); + if (r < 0) + return r; + + b->bus_client = true; + + /* We don't know whether the bus is trusted or not, so better + * be safe, and authenticate everything */ + b->trusted = false; + b->is_local = false; + b->creds_mask |= SD_BUS_CREDS_UID | SD_BUS_CREDS_EUID | SD_BUS_CREDS_EFFECTIVE_CAPS; + + r = sd_bus_start(b); + if (r < 0) + return r; + + *ret = TAKE_PTR(b); + return 0; +} + +_public_ int sd_bus_open(sd_bus **ret) { + return sd_bus_open_with_description(ret, NULL); +} + +int bus_set_address_system(sd_bus *b) { + const char *e; + int r; + + assert(b); + + e = secure_getenv("DBUS_SYSTEM_BUS_ADDRESS"); + + r = sd_bus_set_address(b, e ?: DEFAULT_SYSTEM_BUS_ADDRESS); + if (r < 0) + return r; + + b->runtime_scope = RUNTIME_SCOPE_SYSTEM; + return r; +} + +_public_ int sd_bus_open_system_with_description(sd_bus **ret, const char *description) { + _cleanup_(bus_freep) sd_bus *b = NULL; + int r; + + assert_return(ret, -EINVAL); + + r = sd_bus_new(&b); + if (r < 0) + return r; + + if (description) { + r = sd_bus_set_description(b, description); + if (r < 0) + return r; + } + + r = bus_set_address_system(b); + if (r < 0) + return r; + + b->bus_client = true; + + /* Let's do per-method access control on the system bus. We + * need the caller's UID and capability set for that. */ + b->trusted = false; + b->creds_mask |= SD_BUS_CREDS_UID | SD_BUS_CREDS_EUID | SD_BUS_CREDS_EFFECTIVE_CAPS; + b->is_local = true; + + r = sd_bus_start(b); + if (r < 0) + return r; + + *ret = TAKE_PTR(b); + return 0; +} + +_public_ int sd_bus_open_system(sd_bus **ret) { + return sd_bus_open_system_with_description(ret, NULL); +} + +int bus_set_address_user(sd_bus *b) { + const char *a; + _cleanup_free_ char *_a = NULL; + int r; + + assert(b); + + a = secure_getenv("DBUS_SESSION_BUS_ADDRESS"); + if (!a) { + const char *e; + _cleanup_free_ char *ee = NULL; + + e = secure_getenv("XDG_RUNTIME_DIR"); + if (!e) + return log_debug_errno(SYNTHETIC_ERRNO(ENOMEDIUM), + "sd-bus: $XDG_RUNTIME_DIR not set, cannot connect to user bus."); + + ee = bus_address_escape(e); + if (!ee) + return -ENOMEM; + + if (asprintf(&_a, DEFAULT_USER_BUS_ADDRESS_FMT, ee) < 0) + return -ENOMEM; + a = _a; + } + + r = sd_bus_set_address(b, a); + if (r < 0) + return r; + + b->runtime_scope = RUNTIME_SCOPE_USER; + return r; +} + +_public_ int sd_bus_open_user_with_description(sd_bus **ret, const char *description) { + _cleanup_(bus_freep) sd_bus *b = NULL; + int r; + + assert_return(ret, -EINVAL); + + r = sd_bus_new(&b); + if (r < 0) + return r; + + if (description) { + r = sd_bus_set_description(b, description); + if (r < 0) + return r; + } + + r = bus_set_address_user(b); + if (r < 0) + return r; + + b->bus_client = true; + + /* We don't do any per-method access control on the user bus. */ + b->trusted = true; + b->is_local = true; + + r = sd_bus_start(b); + if (r < 0) + return r; + + *ret = TAKE_PTR(b); + return 0; +} + +_public_ int sd_bus_open_user(sd_bus **ret) { + return sd_bus_open_user_with_description(ret, NULL); +} + +int bus_set_address_system_remote(sd_bus *b, const char *host) { + _cleanup_free_ char *e = NULL; + char *m = NULL, *c = NULL, *a, *rbracket = NULL, *p = NULL; + + assert(b); + assert(host); + + /* Skip ":"s in ipv6 addresses */ + if (*host == '[') { + char *t; + + rbracket = strchr(host, ']'); + if (!rbracket) + return -EINVAL; + t = strndupa_safe(host + 1, rbracket - host - 1); + e = bus_address_escape(t); + if (!e) + return -ENOMEM; + } else if ((a = strchr(host, '@'))) { + if (*(a + 1) == '[') { + _cleanup_free_ char *t = NULL; + + rbracket = strchr(a + 1, ']'); + if (!rbracket) + return -EINVAL; + t = new0(char, strlen(host)); + if (!t) + return -ENOMEM; + strncat(t, host, a - host + 1); + strncat(t, a + 2, rbracket - a - 2); + e = bus_address_escape(t); + if (!e) + return -ENOMEM; + } else if (*(a + 1) == '\0' || strchr(a + 1, '@')) + return -EINVAL; + } + + /* Let's see if a port was given */ + m = strchr(rbracket ? rbracket + 1 : host, ':'); + if (m) { + char *t; + bool got_forward_slash = false; + + p = m + 1; + + t = strchr(p, '/'); + if (t) { + p = strndupa_safe(p, t - p); + got_forward_slash = true; + } + + if (!in_charset(p, "0123456789") || *p == '\0') { + if (!hostname_is_valid(p, 0) || got_forward_slash) + return -EINVAL; + + m = TAKE_PTR(p); + goto interpret_port_as_machine_old_syntax; + } + } + + /* Let's see if a machine was given */ + m = strchr(rbracket ? rbracket + 1 : host, '/'); + if (m) { + m++; +interpret_port_as_machine_old_syntax: + /* Let's make sure this is not a port of some kind, + * and is a valid machine name. */ + if (!in_charset(m, "0123456789") && hostname_is_valid(m, 0)) + c = strjoina(",argv", p ? "7" : "5", "=--machine=", m); + } + + if (!e) { + char *t; + + t = strndupa_safe(host, strcspn(host, ":/")); + + e = bus_address_escape(t); + if (!e) + return -ENOMEM; + } + + a = strjoin("unixexec:path=ssh,argv1=-xT", p ? ",argv2=-p,argv3=" : "", strempty(p), + ",argv", p ? "4" : "2", "=--,argv", p ? "5" : "3", "=", e, + ",argv", p ? "6" : "4", "=systemd-stdio-bridge", c); + if (!a) + return -ENOMEM; + + return free_and_replace(b->address, a); +} + +_public_ int sd_bus_open_system_remote(sd_bus **ret, const char *host) { + _cleanup_(bus_freep) sd_bus *b = NULL; + int r; + + assert_return(host, -EINVAL); + assert_return(ret, -EINVAL); + + r = sd_bus_new(&b); + if (r < 0) + return r; + + r = bus_set_address_system_remote(b, host); + if (r < 0) + return r; + + b->bus_client = true; + b->trusted = false; + b->runtime_scope = RUNTIME_SCOPE_SYSTEM; + b->is_local = false; + + r = sd_bus_start(b); + if (r < 0) + return r; + + *ret = TAKE_PTR(b); + return 0; +} + +int bus_set_address_machine(sd_bus *b, RuntimeScope runtime_scope, const char *machine) { + _cleanup_free_ char *a = NULL; + const char *rhs; + + assert(b); + assert(machine); + + rhs = strchr(machine, '@'); + if (rhs || runtime_scope == RUNTIME_SCOPE_USER) { + _cleanup_free_ char *u = NULL, *eu = NULL, *erhs = NULL; + + /* If there's an "@" in the container specification, we'll connect as a user specified at its + * left hand side, which is useful in combination with user=true. This isn't as trivial as it + * might sound: it's not sufficient to enter the container and connect to some socket there, + * since the --user socket path depends on $XDG_RUNTIME_DIR which is set via PAM. Thus, to be + * able to connect, we need to have a PAM session. Our way out? We use systemd-run to get + * into the container and acquire a PAM session there, and then invoke systemd-stdio-bridge + * in it, which propagates the bus transport to us. */ + + if (rhs) { + if (rhs > machine) + u = strndup(machine, rhs - machine); + else + u = getusername_malloc(); /* Empty user name, let's use the local one */ + if (!u) + return -ENOMEM; + + eu = bus_address_escape(u); + if (!eu) + return -ENOMEM; + + rhs++; + } else { + /* No "@" specified but we shall connect to the user instance? Then assume root (and + * not a user named identically to the calling one). This means: + * + * --machine=foobar --user → connect to user bus of root user in container "foobar" + * --machine=@foobar --user → connect to user bus of user named like the calling user in container "foobar" + * + * Why? so that behaviour for "--machine=foobar --system" is roughly similar to + * "--machine=foobar --user": both times we unconditionally connect as root user + * regardless what the calling user is. */ + + rhs = machine; + } + + if (!isempty(rhs)) { + erhs = bus_address_escape(rhs); + if (!erhs) + return -ENOMEM; + } + + /* systemd-run -M… -PGq --wait -pUser=… -pPAMName=login systemd-stdio-bridge */ + + a = strjoin("unixexec:path=systemd-run," + "argv1=-M", erhs ?: ".host", "," + "argv2=-PGq," + "argv3=--wait," + "argv4=-pUser%3d", eu ?: "root", ",", + "argv5=-pPAMName%3dlogin," + "argv6=systemd-stdio-bridge"); + if (!a) + return -ENOMEM; + + if (runtime_scope == RUNTIME_SCOPE_USER) { + /* Ideally we'd use the "--user" switch to systemd-stdio-bridge here, but it's only + * available in recent systemd versions. Using the "-p" switch with the explicit path + * is a working alternative, and is compatible with older versions, hence that's what + * we use here. */ + if (!strextend(&a, ",argv7=-punix:path%3d%24%7bXDG_RUNTIME_DIR%7d/bus")) + return -ENOMEM; + } + } else { + _cleanup_free_ char *e = NULL; + + /* Just a container name, we can go the simple way, and just join the container, and connect + * to the well-known path of the system bus there. */ + + e = bus_address_escape(machine); + if (!e) + return -ENOMEM; + + a = strjoin("x-machine-unix:machine=", e); + if (!a) + return -ENOMEM; + } + + return free_and_replace(b->address, a); +} + +static int user_and_machine_valid(const char *user_and_machine) { + const char *h; + + /* Checks if a container specification in the form "user@container" or just "container" is valid. + * + * If the "@" syntax is used we'll allow either the "user" or the "container" part to be omitted, but + * not both. */ + + h = strchr(user_and_machine, '@'); + if (!h) + h = user_and_machine; + else { + _cleanup_free_ char *user = NULL; + + user = strndup(user_and_machine, h - user_and_machine); + if (!user) + return -ENOMEM; + + if (!isempty(user) && !valid_user_group_name(user, VALID_USER_RELAX | VALID_USER_ALLOW_NUMERIC)) + return false; + + h++; + + if (isempty(h)) + return !isempty(user); + } + + return hostname_is_valid(h, VALID_HOSTNAME_DOT_HOST); +} + +static int user_and_machine_equivalent(const char *user_and_machine) { + _cleanup_free_ char *un = NULL; + const char *f; + + /* Returns true if the specified user+machine name are actually equivalent to our own identity and + * our own host. If so we can shortcut things. Why bother? Because that way we don't have to fork + * off short-lived worker processes that are then unavailable for authentication and logging in the + * peer. Moreover joining a namespace requires privileges. If we are in the right namespace anyway, + * we can avoid permission problems thus. */ + + assert(user_and_machine); + + /* Omitting the user name means that we shall use the same user name as we run as locally, which + * means we'll end up on the same host, let's shortcut */ + if (streq(user_and_machine, "@.host")) + return true; + + /* Otherwise, if we are root, then we can also allow the ".host" syntax, as that's the user this + * would connect to. */ + uid_t uid = geteuid(); + + if (uid == 0 && STR_IN_SET(user_and_machine, ".host", "root@.host", "0@.host")) + return true; + + /* Otherwise, we have to figure out our user id and name, and compare things with that. */ + char buf[DECIMAL_STR_MAX(uid_t)]; + xsprintf(buf, UID_FMT, uid); + + f = startswith(user_and_machine, buf); + if (!f) { + un = getusername_malloc(); + if (!un) + return -ENOMEM; + + f = startswith(user_and_machine, un); + if (!f) + return false; + } + + return STR_IN_SET(f, "@", "@.host"); +} + +_public_ int sd_bus_open_system_machine(sd_bus **ret, const char *user_and_machine) { + _cleanup_(bus_freep) sd_bus *b = NULL; + int r; + + assert_return(user_and_machine, -EINVAL); + assert_return(ret, -EINVAL); + + if (user_and_machine_equivalent(user_and_machine)) + return sd_bus_open_system(ret); + + r = user_and_machine_valid(user_and_machine); + if (r < 0) + return r; + if (r == 0) + return -EINVAL; + + r = sd_bus_new(&b); + if (r < 0) + return r; + + r = bus_set_address_machine(b, RUNTIME_SCOPE_SYSTEM, user_and_machine); + if (r < 0) + return r; + + b->bus_client = true; + b->runtime_scope = RUNTIME_SCOPE_SYSTEM; + + r = sd_bus_start(b); + if (r < 0) + return r; + + *ret = TAKE_PTR(b); + return 0; +} + +_public_ int sd_bus_open_user_machine(sd_bus **ret, const char *user_and_machine) { + _cleanup_(bus_freep) sd_bus *b = NULL; + int r; + + assert_return(user_and_machine, -EINVAL); + assert_return(ret, -EINVAL); + + /* Shortcut things if we'd end up on this host and as the same user. */ + if (user_and_machine_equivalent(user_and_machine)) + return sd_bus_open_user(ret); + + r = user_and_machine_valid(user_and_machine); + if (r < 0) + return r; + if (r == 0) + return -EINVAL; + + r = sd_bus_new(&b); + if (r < 0) + return r; + + r = bus_set_address_machine(b, RUNTIME_SCOPE_USER, user_and_machine); + if (r < 0) + return r; + + b->bus_client = true; + b->trusted = true; + + r = sd_bus_start(b); + if (r < 0) + return r; + + *ret = TAKE_PTR(b); + return 0; +} + +_public_ void sd_bus_close(sd_bus *bus) { + if (!bus) + return; + if (bus->state == BUS_CLOSED) + return; + if (bus_origin_changed(bus)) + return; + + /* Don't leave ssh hanging around */ + bus_kill_exec(bus); + + bus_set_state(bus, BUS_CLOSED); + + sd_bus_detach_event(bus); + + /* Drop all queued messages so that they drop references to + * the bus object and the bus may be freed */ + bus_reset_queues(bus); + + bus_close_io_fds(bus); + bus_close_inotify_fd(bus); +} + +_public_ sd_bus *sd_bus_close_unref(sd_bus *bus) { + if (!bus) + return NULL; + if (bus_origin_changed(bus)) + return NULL; + + sd_bus_close(bus); + + return sd_bus_unref(bus); +} + +_public_ sd_bus* sd_bus_flush_close_unref(sd_bus *bus) { + if (!bus) + return NULL; + if (bus_origin_changed(bus)) + return NULL; + + /* Have to do this before flush() to prevent hang */ + bus_kill_exec(bus); + sd_bus_flush(bus); + + return sd_bus_close_unref(bus); +} + +void bus_enter_closing(sd_bus *bus) { + assert(bus); + + if (!IN_SET(bus->state, BUS_WATCH_BIND, BUS_OPENING, BUS_AUTHENTICATING, BUS_HELLO, BUS_RUNNING)) + return; + + bus_set_state(bus, BUS_CLOSING); +} + +/* Define manually so we can add the PID check */ +_public_ sd_bus *sd_bus_ref(sd_bus *bus) { + if (!bus) + return NULL; + if (bus_origin_changed(bus)) + return NULL; + + bus->n_ref++; + + return bus; +} + +_public_ sd_bus* sd_bus_unref(sd_bus *bus) { + if (!bus) + return NULL; + if (bus_origin_changed(bus)) + return NULL; + + assert(bus->n_ref > 0); + if (--bus->n_ref > 0) + return NULL; + + return bus_free(bus); +} + +_public_ int sd_bus_is_open(sd_bus *bus) { + if (!bus) + return 0; + + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return BUS_IS_OPEN(bus->state); +} + +_public_ int sd_bus_is_ready(sd_bus *bus) { + if (!bus) + return 0; + + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->state == BUS_RUNNING; +} + +_public_ int sd_bus_can_send(sd_bus *bus, char type) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->state != BUS_UNSET, -ENOTCONN); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (bus->is_monitor) + return 0; + + if (type == SD_BUS_TYPE_UNIX_FD) { + if (!bus->accept_fd) + return 0; + + r = bus_ensure_running(bus); + if (r < 0) + return r; + + return bus->can_fds; + } + + return bus_type_is_valid(type); +} + +_public_ int sd_bus_get_bus_id(sd_bus *bus, sd_id128_t *id) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(id, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + r = bus_ensure_running(bus); + if (r < 0) + return r; + + *id = bus->server_id; + return 0; +} + +#define COOKIE_CYCLED (UINT32_C(1) << 31) + +static uint64_t cookie_inc(uint64_t cookie) { + + /* Stay within the 32-bit range, since classic D-Bus can't deal with more */ + if (cookie >= UINT32_MAX) + return COOKIE_CYCLED; /* Don't go back to zero, but use the highest bit for checking + * whether we are looping. */ + + return cookie + 1; +} + +static int next_cookie(sd_bus *b) { + uint64_t new_cookie; + + assert(b); + + new_cookie = cookie_inc(b->cookie); + + /* Small optimization: don't bother with checking for cookie reuse until we overran cookiespace at + * least once, but then do it thorougly. */ + if (FLAGS_SET(new_cookie, COOKIE_CYCLED)) { + uint32_t i; + + /* Check if the cookie is currently in use. If so, pick the next one */ + for (i = 0; i < COOKIE_CYCLED; i++) { + if (!ordered_hashmap_contains(b->reply_callbacks, &new_cookie)) + goto good; + + new_cookie = cookie_inc(new_cookie); + } + + /* Can't fulfill request */ + return -EBUSY; + } + +good: + b->cookie = new_cookie; + return 0; +} + +static int bus_seal_message(sd_bus *b, sd_bus_message *m, usec_t timeout) { + int r; + + assert(b); + assert(m); + + if (m->sealed) { + /* If we copy the same message to multiple + * destinations, avoid using the same cookie + * numbers. */ + b->cookie = MAX(b->cookie, BUS_MESSAGE_COOKIE(m)); + return 0; + } + + if (timeout == 0) { + r = sd_bus_get_method_call_timeout(b, &timeout); + if (r < 0) + return r; + } + + if (!m->sender && b->patch_sender) { + r = sd_bus_message_set_sender(m, b->patch_sender); + if (r < 0) + return r; + } + + r = next_cookie(b); + if (r < 0) + return r; + + return sd_bus_message_seal(m, b->cookie, timeout); +} + +static int bus_remarshal_message(sd_bus *b, sd_bus_message **m) { + bool remarshal = false; + + assert(b); + + /* wrong packet version */ + if (b->message_version != 0 && b->message_version != (*m)->header->version) + remarshal = true; + + /* wrong packet endianness */ + if (b->message_endian != 0 && b->message_endian != (*m)->header->endian) + remarshal = true; + + return remarshal ? bus_message_remarshal(b, m) : 0; +} + +int bus_seal_synthetic_message(sd_bus *b, sd_bus_message *m) { + assert(b); + assert(m); + + /* Fake some timestamps, if they were requested, and not + * already initialized */ + if (b->attach_timestamp) { + if (m->realtime <= 0) + m->realtime = now(CLOCK_REALTIME); + + if (m->monotonic <= 0) + m->monotonic = now(CLOCK_MONOTONIC); + } + + /* The bus specification says the serial number cannot be 0, + * hence let's fill something in for synthetic messages. Since + * synthetic messages might have a fake sender and we don't + * want to interfere with the real sender's serial numbers we + * pick a fixed, artificial one. */ + return sd_bus_message_seal(m, UINT32_MAX, 0); +} + +static int bus_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) { + int r; + + assert(bus); + assert(m); + + r = bus_socket_write_message(bus, m, idx); + if (r <= 0) + return r; + + if (*idx >= BUS_MESSAGE_SIZE(m)) + log_debug("Sent message type=%s sender=%s destination=%s path=%s interface=%s member=%s" + " cookie=%" PRIu64 " reply_cookie=%" PRIu64 + " signature=%s error-name=%s error-message=%s", + bus_message_type_to_string(m->header->type), + strna(sd_bus_message_get_sender(m)), + strna(sd_bus_message_get_destination(m)), + strna(sd_bus_message_get_path(m)), + strna(sd_bus_message_get_interface(m)), + strna(sd_bus_message_get_member(m)), + BUS_MESSAGE_COOKIE(m), + m->reply_cookie, + strna(m->root_container.signature), + strna(m->error.name), + strna(m->error.message)); + + return r; +} + +static int dispatch_wqueue(sd_bus *bus) { + int r, ret = 0; + + assert(bus); + assert(IN_SET(bus->state, BUS_RUNNING, BUS_HELLO)); + + while (bus->wqueue_size > 0) { + + r = bus_write_message(bus, bus->wqueue[0], &bus->windex); + if (r < 0) + return r; + else if (r == 0) + /* Didn't do anything this time */ + return ret; + else if (bus->windex >= BUS_MESSAGE_SIZE(bus->wqueue[0])) { + /* Fully written. Let's drop the entry from + * the queue. + * + * This isn't particularly optimized, but + * well, this is supposed to be our worst-case + * buffer only, and the socket buffer is + * supposed to be our primary buffer, and if + * it got full, then all bets are off + * anyway. */ + + bus->wqueue_size--; + bus_message_unref_queued(bus->wqueue[0], bus); + memmove(bus->wqueue, bus->wqueue + 1, sizeof(sd_bus_message*) * bus->wqueue_size); + bus->windex = 0; + + ret = 1; + } + } + + return ret; +} + +static int bus_read_message(sd_bus *bus) { + assert(bus); + + return bus_socket_read_message(bus); +} + +int bus_rqueue_make_room(sd_bus *bus) { + assert(bus); + + if (bus->rqueue_size >= BUS_RQUEUE_MAX) + return -ENOBUFS; + + if (!GREEDY_REALLOC(bus->rqueue, bus->rqueue_size + 1)) + return -ENOMEM; + + return 0; +} + +static void rqueue_drop_one(sd_bus *bus, size_t i) { + assert(bus); + assert(i < bus->rqueue_size); + + bus_message_unref_queued(bus->rqueue[i], bus); + memmove(bus->rqueue + i, bus->rqueue + i + 1, sizeof(sd_bus_message*) * (bus->rqueue_size - i - 1)); + bus->rqueue_size--; +} + +static int dispatch_rqueue(sd_bus *bus, sd_bus_message **m) { + int r, ret = 0; + + assert(bus); + assert(m); + assert(IN_SET(bus->state, BUS_RUNNING, BUS_HELLO)); + + for (;;) { + if (bus->rqueue_size > 0) { + /* Dispatch a queued message */ + *m = sd_bus_message_ref(bus->rqueue[0]); + rqueue_drop_one(bus, 0); + return 1; + } + + /* Try to read a new message */ + r = bus_read_message(bus); + if (r < 0) + return r; + if (r == 0) { + *m = NULL; + return ret; + } + + ret = 1; + } +} + +_public_ int sd_bus_send(sd_bus *bus, sd_bus_message *_m, uint64_t *cookie) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = sd_bus_message_ref(_m); + int r; + + assert_return(m, -EINVAL); + + if (bus) + assert_return(bus = bus_resolve(bus), -ENOPKG); + else + assert_return(bus = m->bus, -ENOTCONN); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + if (m->n_fds > 0) { + r = sd_bus_can_send(bus, SD_BUS_TYPE_UNIX_FD); + if (r < 0) + return r; + if (r == 0) + return -EOPNOTSUPP; + } + + /* If the cookie number isn't kept, then we know that no reply + * is expected */ + if (!cookie && !m->sealed) + m->header->flags |= BUS_MESSAGE_NO_REPLY_EXPECTED; + + r = bus_seal_message(bus, m, 0); + if (r < 0) + return r; + + /* Remarshall if we have to. This will possibly unref the + * message and place a replacement in m */ + r = bus_remarshal_message(bus, &m); + if (r < 0) + return r; + + /* If this is a reply and no reply was requested, then let's + * suppress this, if we can */ + if (m->dont_send) + goto finish; + + if (IN_SET(bus->state, BUS_RUNNING, BUS_HELLO) && bus->wqueue_size <= 0) { + size_t idx = 0; + + r = bus_write_message(bus, m, &idx); + if (ERRNO_IS_NEG_DISCONNECT(r)) { + bus_enter_closing(bus); + return -ECONNRESET; + } else if (r < 0) + return r; + + if (idx < BUS_MESSAGE_SIZE(m)) { + /* Wasn't fully written. So let's remember how + * much was written. Note that the first entry + * of the wqueue array is always allocated so + * that we always can remember how much was + * written. */ + bus->wqueue[0] = bus_message_ref_queued(m, bus); + bus->wqueue_size = 1; + bus->windex = idx; + } + + } else { + /* Just append it to the queue. */ + + if (bus->wqueue_size >= BUS_WQUEUE_MAX) + return -ENOBUFS; + + if (!GREEDY_REALLOC(bus->wqueue, bus->wqueue_size + 1)) + return -ENOMEM; + + bus->wqueue[bus->wqueue_size++] = bus_message_ref_queued(m, bus); + } + +finish: + if (cookie) + *cookie = BUS_MESSAGE_COOKIE(m); + + return 1; +} + +_public_ int sd_bus_send_to(sd_bus *bus, sd_bus_message *m, const char *destination, uint64_t *cookie) { + int r; + + assert_return(m, -EINVAL); + + if (bus) + assert_return(bus = bus_resolve(bus), -ENOPKG); + else + assert_return(bus = m->bus, -ENOTCONN); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + if (!streq_ptr(m->destination, destination)) { + + if (!destination) + return -EEXIST; + + r = sd_bus_message_set_destination(m, destination); + if (r < 0) + return r; + } + + return sd_bus_send(bus, m, cookie); +} + +static usec_t calc_elapse(sd_bus *bus, uint64_t usec) { + assert(bus); + + assert_cc(sizeof(usec_t) == sizeof(uint64_t)); + + if (usec == USEC_INFINITY) + return 0; + + /* We start all timeouts the instant we enter BUS_HELLO/BUS_RUNNING state, so that the don't run in parallel + * with any connection setup states. Hence, if a method callback is started earlier than that we just store the + * relative timestamp, and afterwards the absolute one. */ + + if (IN_SET(bus->state, BUS_WATCH_BIND, BUS_OPENING, BUS_AUTHENTICATING)) + return usec; + else + return usec_add(now(CLOCK_MONOTONIC), usec); +} + +static int timeout_compare(const void *a, const void *b) { + const struct reply_callback *x = a, *y = b; + + if (x->timeout_usec != 0 && y->timeout_usec == 0) + return -1; + + if (x->timeout_usec == 0 && y->timeout_usec != 0) + return 1; + + return CMP(x->timeout_usec, y->timeout_usec); +} + +_public_ int sd_bus_call_async( + sd_bus *bus, + sd_bus_slot **slot, + sd_bus_message *_m, + sd_bus_message_handler_t callback, + void *userdata, + uint64_t usec) { + + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = sd_bus_message_ref(_m); + _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *s = NULL; + int r; + + assert_return(m, -EINVAL); + assert_return(m->header->type == SD_BUS_MESSAGE_METHOD_CALL, -EINVAL); + assert_return(!m->sealed || (!!callback == !(m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED)), -EINVAL); + + if (bus) + assert_return(bus = bus_resolve(bus), -ENOPKG); + else + assert_return(bus = m->bus, -ENOTCONN); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + /* If no callback is specified and there's no interest in a slot, then there's no reason to ask for a reply */ + if (!callback && !slot && !m->sealed) + m->header->flags |= BUS_MESSAGE_NO_REPLY_EXPECTED; + + r = ordered_hashmap_ensure_allocated(&bus->reply_callbacks, &uint64_hash_ops); + if (r < 0) + return r; + + r = prioq_ensure_allocated(&bus->reply_callbacks_prioq, timeout_compare); + if (r < 0) + return r; + + r = bus_seal_message(bus, m, usec); + if (r < 0) + return r; + + r = bus_remarshal_message(bus, &m); + if (r < 0) + return r; + + if (slot || callback) { + s = bus_slot_allocate(bus, !slot, BUS_REPLY_CALLBACK, sizeof(struct reply_callback), userdata); + if (!s) + return -ENOMEM; + + s->reply_callback.callback = callback; + + s->reply_callback.cookie = BUS_MESSAGE_COOKIE(m); + r = ordered_hashmap_put(bus->reply_callbacks, &s->reply_callback.cookie, &s->reply_callback); + if (r < 0) { + s->reply_callback.cookie = 0; + return r; + } + + s->reply_callback.timeout_usec = calc_elapse(bus, m->timeout); + if (s->reply_callback.timeout_usec != 0) { + r = prioq_put(bus->reply_callbacks_prioq, &s->reply_callback, &s->reply_callback.prioq_idx); + if (r < 0) { + s->reply_callback.timeout_usec = 0; + return r; + } + } + } + + r = sd_bus_send(bus, m, s ? &s->reply_callback.cookie : NULL); + if (r < 0) + return r; + + if (slot) + *slot = s; + s = NULL; + + return r; +} + +int bus_ensure_running(sd_bus *bus) { + int r; + + assert(bus); + + if (bus->state == BUS_RUNNING) + return 1; + + for (;;) { + if (IN_SET(bus->state, BUS_UNSET, BUS_CLOSED, BUS_CLOSING)) + return -ENOTCONN; + + r = sd_bus_process(bus, NULL); + if (r < 0) + return r; + if (bus->state == BUS_RUNNING) + return 1; + if (r > 0) + continue; + + r = sd_bus_wait(bus, UINT64_MAX); + if (r < 0) + return r; + } +} + +_public_ int sd_bus_call( + sd_bus *bus, + sd_bus_message *_m, + uint64_t usec, + sd_bus_error *error, + sd_bus_message **reply) { + + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = sd_bus_message_ref(_m); + usec_t timeout; + uint64_t cookie; + size_t i; + int r; + + bus_assert_return(m, -EINVAL, error); + bus_assert_return(m->header->type == SD_BUS_MESSAGE_METHOD_CALL, -EINVAL, error); + bus_assert_return(!(m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED), -EINVAL, error); + bus_assert_return(!bus_error_is_dirty(error), -EINVAL, error); + + if (bus) + assert_return(bus = bus_resolve(bus), -ENOPKG); + else + assert_return(bus = m->bus, -ENOTCONN); + bus_assert_return(!bus_origin_changed(bus), -ECHILD, error); + + if (!BUS_IS_OPEN(bus->state)) { + r = -ENOTCONN; + goto fail; + } + + r = bus_ensure_running(bus); + if (r < 0) + goto fail; + + i = bus->rqueue_size; + + r = bus_seal_message(bus, m, usec); + if (r < 0) + goto fail; + + r = bus_remarshal_message(bus, &m); + if (r < 0) + goto fail; + + r = sd_bus_send(bus, m, &cookie); + if (r < 0) + goto fail; + + timeout = calc_elapse(bus, m->timeout); + + for (;;) { + usec_t left; + + while (i < bus->rqueue_size) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *incoming = NULL; + + incoming = sd_bus_message_ref(bus->rqueue[i]); + + if (incoming->reply_cookie == cookie) { + /* Found a match! */ + + rqueue_drop_one(bus, i); + log_debug_bus_message(incoming); + + if (incoming->header->type == SD_BUS_MESSAGE_METHOD_RETURN) { + + if (incoming->n_fds <= 0 || bus->accept_fd) { + if (reply) + *reply = TAKE_PTR(incoming); + + return 1; + } + + return sd_bus_error_set(error, SD_BUS_ERROR_INCONSISTENT_MESSAGE, + "Reply message contained file descriptors which I couldn't accept. Sorry."); + + } else if (incoming->header->type == SD_BUS_MESSAGE_METHOD_ERROR) + return sd_bus_error_copy(error, &incoming->error); + else { + r = -EIO; + goto fail; + } + + } else if (BUS_MESSAGE_COOKIE(incoming) == cookie && + bus->unique_name && + incoming->sender && + streq(bus->unique_name, incoming->sender)) { + + rqueue_drop_one(bus, i); + + /* Our own message? Somebody is trying to send its own client a message, + * let's not dead-lock, let's fail immediately. */ + + r = -ELOOP; + goto fail; + } + + /* Try to read more, right-away */ + i++; + } + + r = bus_read_message(bus); + if (r < 0) { + if (ERRNO_IS_DISCONNECT(r)) { + bus_enter_closing(bus); + r = -ECONNRESET; + } + + goto fail; + } + if (r > 0) + continue; + + if (timeout > 0) { + usec_t n; + + n = now(CLOCK_MONOTONIC); + if (n >= timeout) { + r = -ETIMEDOUT; + goto fail; + } + + left = timeout - n; + } else + left = UINT64_MAX; + + r = bus_poll(bus, true, left); + if (ERRNO_IS_NEG_TRANSIENT(r)) + continue; + if (r < 0) + goto fail; + if (r == 0) { + r = -ETIMEDOUT; + goto fail; + } + + r = dispatch_wqueue(bus); + if (r < 0) { + if (ERRNO_IS_DISCONNECT(r)) { + bus_enter_closing(bus); + r = -ECONNRESET; + } + + goto fail; + } + } + +fail: + return sd_bus_error_set_errno(error, r); +} + +_public_ int sd_bus_get_fd(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(bus->input_fd == bus->output_fd, -EPERM); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (bus->state == BUS_CLOSED) + return -ENOTCONN; + + if (bus->inotify_fd >= 0) + return bus->inotify_fd; + + if (bus->input_fd >= 0) + return bus->input_fd; + + return -ENOTCONN; +} + +_public_ int sd_bus_get_events(sd_bus *bus) { + int flags = 0; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + switch (bus->state) { + + case BUS_UNSET: + case BUS_CLOSED: + return -ENOTCONN; + + case BUS_WATCH_BIND: + flags |= POLLIN; + break; + + case BUS_OPENING: + flags |= POLLOUT; + break; + + case BUS_AUTHENTICATING: + if (bus_socket_auth_needs_write(bus)) + flags |= POLLOUT; + + flags |= POLLIN; + break; + + case BUS_RUNNING: + case BUS_HELLO: + if (bus->rqueue_size <= 0) + flags |= POLLIN; + if (bus->wqueue_size > 0) + flags |= POLLOUT; + break; + + case BUS_CLOSING: + break; + + default: + assert_not_reached(); + } + + return flags; +} + +_public_ int sd_bus_get_timeout(sd_bus *bus, uint64_t *timeout_usec) { + struct reply_callback *c; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(timeout_usec, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state) && bus->state != BUS_CLOSING) + return -ENOTCONN; + + if (bus->track_queue) { + *timeout_usec = 0; + return 1; + } + + switch (bus->state) { + + case BUS_AUTHENTICATING: + *timeout_usec = bus->auth_timeout; + return 1; + + case BUS_RUNNING: + case BUS_HELLO: + if (bus->rqueue_size > 0) { + *timeout_usec = 0; + return 1; + } + + c = prioq_peek(bus->reply_callbacks_prioq); + if (!c) { + *timeout_usec = UINT64_MAX; + return 0; + } + + if (c->timeout_usec == 0) { + *timeout_usec = UINT64_MAX; + return 0; + } + + *timeout_usec = c->timeout_usec; + return 1; + + case BUS_CLOSING: + *timeout_usec = 0; + return 1; + + case BUS_WATCH_BIND: + case BUS_OPENING: + *timeout_usec = UINT64_MAX; + return 0; + + default: + assert_not_reached(); + } +} + +static int process_timeout(sd_bus *bus) { + _cleanup_(sd_bus_error_free) sd_bus_error error_buffer = SD_BUS_ERROR_NULL; + _cleanup_(sd_bus_message_unrefp) sd_bus_message* m = NULL; + struct reply_callback *c; + sd_bus_slot *slot; + bool is_hello; + usec_t n; + int r; + + assert(bus); + assert(IN_SET(bus->state, BUS_RUNNING, BUS_HELLO)); + + c = prioq_peek(bus->reply_callbacks_prioq); + if (!c) + return 0; + + n = now(CLOCK_MONOTONIC); + if (c->timeout_usec > n) + return 0; + + r = bus_message_new_synthetic_error( + bus, + c->cookie, + &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_REPLY, "Method call timed out"), + &m); + if (r < 0) + return r; + + m->read_counter = ++bus->read_counter; + + r = bus_seal_synthetic_message(bus, m); + if (r < 0) + return r; + + assert_se(prioq_pop(bus->reply_callbacks_prioq) == c); + c->timeout_usec = 0; + + ordered_hashmap_remove(bus->reply_callbacks, &c->cookie); + c->cookie = 0; + + slot = container_of(c, sd_bus_slot, reply_callback); + + bus->iteration_counter++; + + is_hello = bus->state == BUS_HELLO && c->callback == hello_callback; + + bus->current_message = m; + bus->current_slot = sd_bus_slot_ref(slot); + bus->current_handler = c->callback; + bus->current_userdata = slot->userdata; + r = c->callback(m, slot->userdata, &error_buffer); + bus->current_userdata = NULL; + bus->current_handler = NULL; + bus->current_slot = NULL; + bus->current_message = NULL; + + if (slot->floating) + bus_slot_disconnect(slot, true); + + sd_bus_slot_unref(slot); + + /* When this is the hello message and it timed out, then make sure to propagate the error up, don't just log + * and ignore the callback handler's return value. */ + if (is_hello) + return r; + + return bus_maybe_reply_error(m, r, &error_buffer); +} + +static int process_hello(sd_bus *bus, sd_bus_message *m) { + assert(bus); + assert(m); + + if (bus->state != BUS_HELLO) + return 0; + + /* Let's make sure the first message on the bus is the HELLO + * reply. But note that we don't actually parse the message + * here (we leave that to the usual handling), we just verify + * we don't let any earlier msg through. */ + + if (!IN_SET(m->header->type, SD_BUS_MESSAGE_METHOD_RETURN, SD_BUS_MESSAGE_METHOD_ERROR)) + return -EIO; + + if (m->reply_cookie != 1) + return -EIO; + + return 0; +} + +static int process_reply(sd_bus *bus, sd_bus_message *m) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *synthetic_reply = NULL; + _cleanup_(sd_bus_error_free) sd_bus_error error_buffer = SD_BUS_ERROR_NULL; + struct reply_callback *c; + sd_bus_slot *slot; + bool is_hello; + int r; + + assert(bus); + assert(m); + + if (!IN_SET(m->header->type, SD_BUS_MESSAGE_METHOD_RETURN, SD_BUS_MESSAGE_METHOD_ERROR)) + return 0; + + if (m->destination && bus->unique_name && !streq_ptr(m->destination, bus->unique_name)) + return 0; + + c = ordered_hashmap_remove(bus->reply_callbacks, &m->reply_cookie); + if (!c) + return 0; + + c->cookie = 0; + + slot = container_of(c, sd_bus_slot, reply_callback); + + if (m->n_fds > 0 && !bus->accept_fd) { + + /* If the reply contained a file descriptor which we + * didn't want we pass an error instead. */ + + r = bus_message_new_synthetic_error( + bus, + m->reply_cookie, + &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INCONSISTENT_MESSAGE, "Reply message contained file descriptor"), + &synthetic_reply); + if (r < 0) + return r; + + /* Copy over original timestamp */ + synthetic_reply->realtime = m->realtime; + synthetic_reply->monotonic = m->monotonic; + synthetic_reply->seqnum = m->seqnum; + synthetic_reply->read_counter = m->read_counter; + + r = bus_seal_synthetic_message(bus, synthetic_reply); + if (r < 0) + return r; + + m = synthetic_reply; + } else { + r = sd_bus_message_rewind(m, true); + if (r < 0) + return r; + } + + if (c->timeout_usec != 0) { + prioq_remove(bus->reply_callbacks_prioq, c, &c->prioq_idx); + c->timeout_usec = 0; + } + + is_hello = bus->state == BUS_HELLO && c->callback == hello_callback; + + bus->current_slot = sd_bus_slot_ref(slot); + bus->current_handler = c->callback; + bus->current_userdata = slot->userdata; + r = c->callback(m, slot->userdata, &error_buffer); + bus->current_userdata = NULL; + bus->current_handler = NULL; + bus->current_slot = NULL; + + if (slot->floating) + bus_slot_disconnect(slot, true); + + sd_bus_slot_unref(slot); + + /* When this is the hello message and it failed, then make sure to propagate the error up, don't just log and + * ignore the callback handler's return value. */ + if (is_hello) + return r; + + return bus_maybe_reply_error(m, r, &error_buffer); +} + +static int process_filter(sd_bus *bus, sd_bus_message *m) { + _cleanup_(sd_bus_error_free) sd_bus_error error_buffer = SD_BUS_ERROR_NULL; + int r; + + assert(bus); + assert(m); + + do { + bus->filter_callbacks_modified = false; + + LIST_FOREACH(callbacks, l, bus->filter_callbacks) { + sd_bus_slot *slot; + + if (bus->filter_callbacks_modified) + break; + + /* Don't run this more than once per iteration */ + if (l->last_iteration == bus->iteration_counter) + continue; + + l->last_iteration = bus->iteration_counter; + + r = sd_bus_message_rewind(m, true); + if (r < 0) + return r; + + slot = container_of(l, sd_bus_slot, filter_callback); + + bus->current_slot = sd_bus_slot_ref(slot); + bus->current_handler = l->callback; + bus->current_userdata = slot->userdata; + r = l->callback(m, slot->userdata, &error_buffer); + bus->current_userdata = NULL; + bus->current_handler = NULL; + bus->current_slot = sd_bus_slot_unref(slot); + + r = bus_maybe_reply_error(m, r, &error_buffer); + if (r != 0) + return r; + + } + + } while (bus->filter_callbacks_modified); + + return 0; +} + +static int process_match(sd_bus *bus, sd_bus_message *m) { + int r; + + assert(bus); + assert(m); + + do { + bus->match_callbacks_modified = false; + + r = bus_match_run(bus, &bus->match_callbacks, m); + if (r != 0) + return r; + + } while (bus->match_callbacks_modified); + + return 0; +} + +static int process_builtin(sd_bus *bus, sd_bus_message *m) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL; + int r; + + assert(bus); + assert(m); + + if (bus->is_monitor) + return 0; + + if (bus->manual_peer_interface) + return 0; + + if (m->header->type != SD_BUS_MESSAGE_METHOD_CALL) + return 0; + + if (!streq_ptr(m->interface, "org.freedesktop.DBus.Peer")) + return 0; + + if (m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) + return 1; + + if (streq_ptr(m->member, "Ping")) + r = sd_bus_message_new_method_return(m, &reply); + else if (streq_ptr(m->member, "GetMachineId")) { + sd_id128_t id; + + r = sd_id128_get_machine(&id); + if (r < 0) + return r; + + r = sd_bus_message_new_method_return(m, &reply); + if (r < 0) + return r; + + r = sd_bus_message_append(reply, "s", SD_ID128_TO_STRING(id)); + } else { + r = sd_bus_message_new_method_errorf( + m, &reply, + SD_BUS_ERROR_UNKNOWN_METHOD, + "Unknown method '%s' on interface '%s'.", m->member, m->interface); + } + if (r < 0) + return r; + + r = sd_bus_send(bus, reply, NULL); + if (r < 0) + return r; + + return 1; +} + +static int process_fd_check(sd_bus *bus, sd_bus_message *m) { + assert(bus); + assert(m); + + /* If we got a message with a file descriptor which we didn't + * want to accept, then let's drop it. How can this even + * happen? For example, when the kernel queues a message into + * an activatable names's queue which allows fds, and then is + * delivered to us later even though we ourselves did not + * negotiate it. */ + + if (bus->is_monitor) + return 0; + + if (m->n_fds <= 0) + return 0; + + if (bus->accept_fd) + return 0; + + if (m->header->type != SD_BUS_MESSAGE_METHOD_CALL) + return 1; /* just eat it up */ + + return sd_bus_reply_method_errorf(m, SD_BUS_ERROR_INCONSISTENT_MESSAGE, + "Message contains file descriptors, which I cannot accept. Sorry."); +} + +static int process_message(sd_bus *bus, sd_bus_message *m) { + _unused_ _cleanup_(log_context_unrefp) LogContext *c = NULL; + int r; + + assert(bus); + assert(m); + + bus->current_message = m; + bus->iteration_counter++; + + if (log_context_enabled()) + c = log_context_new_strv_consume(bus_message_make_log_fields(m)); + + log_debug_bus_message(m); + + r = process_hello(bus, m); + if (r != 0) + goto finish; + + r = process_reply(bus, m); + if (r != 0) + goto finish; + + r = process_fd_check(bus, m); + if (r != 0) + goto finish; + + r = process_filter(bus, m); + if (r != 0) + goto finish; + + r = process_match(bus, m); + if (r != 0) + goto finish; + + r = process_builtin(bus, m); + if (r != 0) + goto finish; + + r = bus_process_object(bus, m); + +finish: + bus->current_message = NULL; + return r; +} + +static int dispatch_track(sd_bus *bus) { + assert(bus); + + if (!bus->track_queue) + return 0; + + bus_track_dispatch(bus->track_queue); + return 1; +} + +static int process_running(sd_bus *bus, sd_bus_message **ret) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; + int r; + + assert(bus); + assert(IN_SET(bus->state, BUS_RUNNING, BUS_HELLO)); + + r = process_timeout(bus); + if (r != 0) + goto null_message; + + r = dispatch_wqueue(bus); + if (r != 0) + goto null_message; + + r = dispatch_track(bus); + if (r != 0) + goto null_message; + + r = dispatch_rqueue(bus, &m); + if (r < 0) + return r; + if (!m) + goto null_message; + + r = process_message(bus, m); + if (r != 0) + goto null_message; + + if (ret) { + r = sd_bus_message_rewind(m, true); + if (r < 0) + return r; + + *ret = TAKE_PTR(m); + return 1; + } + + if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL) { + + log_debug("Unprocessed message call sender=%s object=%s interface=%s member=%s", + strna(sd_bus_message_get_sender(m)), + strna(sd_bus_message_get_path(m)), + strna(sd_bus_message_get_interface(m)), + strna(sd_bus_message_get_member(m))); + + r = sd_bus_reply_method_errorf( + m, + SD_BUS_ERROR_UNKNOWN_OBJECT, + "Unknown object '%s'.", m->path); + if (r < 0) + return r; + } + + return 1; + +null_message: + if (r >= 0 && ret) + *ret = NULL; + + return r; +} + +static int bus_exit_now(sd_bus *bus, sd_event *event) { + assert(bus); + + /* Exit due to close, if this is requested. If this is bus object is attached to an event source, invokes + * sd_event_exit(), otherwise invokes libc exit(). */ + + if (bus->exited) /* did we already exit? */ + return 0; + if (!bus->exit_triggered) /* was the exit condition triggered? */ + return 0; + if (!bus->exit_on_disconnect) /* Shall we actually exit on disconnection? */ + return 0; + + bus->exited = true; /* never exit more than once */ + + log_debug("Bus connection disconnected, exiting."); + + if (!event) + event = bus->event; + + if (event) + return sd_event_exit(event, EXIT_FAILURE); + else + exit(EXIT_FAILURE); + + assert_not_reached(); +} + +static int process_closing_reply_callback(sd_bus *bus, struct reply_callback *c) { + _cleanup_(sd_bus_error_free) sd_bus_error error_buffer = SD_BUS_ERROR_NULL; + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; + sd_bus_slot *slot; + int r; + + assert(bus); + assert(c); + + r = bus_message_new_synthetic_error( + bus, + c->cookie, + &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_REPLY, "Connection terminated"), + &m); + if (r < 0) + return r; + + m->read_counter = ++bus->read_counter; + + r = bus_seal_synthetic_message(bus, m); + if (r < 0) + return r; + + if (c->timeout_usec != 0) { + prioq_remove(bus->reply_callbacks_prioq, c, &c->prioq_idx); + c->timeout_usec = 0; + } + + ordered_hashmap_remove(bus->reply_callbacks, &c->cookie); + c->cookie = 0; + + slot = container_of(c, sd_bus_slot, reply_callback); + + bus->iteration_counter++; + + bus->current_message = m; + bus->current_slot = sd_bus_slot_ref(slot); + bus->current_handler = c->callback; + bus->current_userdata = slot->userdata; + r = c->callback(m, slot->userdata, &error_buffer); + bus->current_userdata = NULL; + bus->current_handler = NULL; + bus->current_slot = NULL; + bus->current_message = NULL; + + if (slot->floating) + bus_slot_disconnect(slot, true); + + sd_bus_slot_unref(slot); + + return bus_maybe_reply_error(m, r, &error_buffer); +} + +static int process_closing(sd_bus *bus, sd_bus_message **ret) { + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; + _cleanup_(sd_event_unrefp) sd_event *event = NULL; + struct reply_callback *c; + int r; + + assert(bus); + assert(bus->state == BUS_CLOSING); + + /* First, fail all outstanding method calls */ + c = ordered_hashmap_first(bus->reply_callbacks); + if (c) + return process_closing_reply_callback(bus, c); + + /* Then, fake-drop all remaining bus tracking references */ + if (bus->tracks) { + bus_track_close(bus->tracks); + return 1; + } + + /* Then, synthesize a Disconnected message */ + r = sd_bus_message_new_signal( + bus, + &m, + "/org/freedesktop/DBus/Local", + "org.freedesktop.DBus.Local", + "Disconnected"); + if (r < 0) + return r; + + bus_message_set_sender_local(bus, m); + m->read_counter = ++bus->read_counter; + + r = bus_seal_synthetic_message(bus, m); + if (r < 0) + return r; + + /* sd_bus_close() will deref the event and set bus->event to NULL. But in bus_exit_now() we use + * bus->event to decide whether to return from the event loop or exit(), but given it's always NULL + * at that point, it always exit(). Ref it here and pass it through further down to avoid that. */ + event = sd_event_ref(bus->event); + sd_bus_close(bus); + + bus->current_message = m; + bus->iteration_counter++; + + r = process_filter(bus, m); + if (r != 0) + goto finish; + + r = process_match(bus, m); + if (r != 0) + goto finish; + + /* Nothing else to do, exit now, if the condition holds */ + bus->exit_triggered = true; + (void) bus_exit_now(bus, event); + + if (ret) + *ret = TAKE_PTR(m); + + r = 1; + +finish: + bus->current_message = NULL; + + return r; +} + +static int bus_process_internal(sd_bus *bus, sd_bus_message **ret) { + int r; + + /* Returns 0 when we didn't do anything. This should cause the + * caller to invoke sd_bus_wait() before returning the next + * time. Returns > 0 when we did something, which possibly + * means *ret is filled in with an unprocessed message. */ + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + /* We don't allow recursively invoking sd_bus_process(). */ + assert_return(!bus->current_message, -EBUSY); + assert(!bus->current_slot); /* This should be NULL whenever bus->current_message is */ + + BUS_DONT_DESTROY(bus); + + switch (bus->state) { + + case BUS_UNSET: + return -ENOTCONN; + + case BUS_CLOSED: + return -ECONNRESET; + + case BUS_WATCH_BIND: + r = bus_socket_process_watch_bind(bus); + break; + + case BUS_OPENING: + r = bus_socket_process_opening(bus); + break; + + case BUS_AUTHENTICATING: + r = bus_socket_process_authenticating(bus); + break; + + case BUS_RUNNING: + case BUS_HELLO: + r = process_running(bus, ret); + if (r >= 0) + return r; + + /* This branch initializes *ret, hence we don't use the generic error checking below */ + break; + + case BUS_CLOSING: + return process_closing(bus, ret); + + default: + assert_not_reached(); + } + + if (ERRNO_IS_NEG_DISCONNECT(r)) { + bus_enter_closing(bus); + r = 1; + } else if (r < 0) + return r; + + if (ret) + *ret = NULL; + + return r; +} + +_public_ int sd_bus_process(sd_bus *bus, sd_bus_message **ret) { + return bus_process_internal(bus, ret); +} + +_public_ int sd_bus_process_priority(sd_bus *bus, int64_t priority, sd_bus_message **ret) { + return bus_process_internal(bus, ret); +} + +static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec) { + struct pollfd p[2] = {}; + usec_t m = USEC_INFINITY; + int r, n; + + assert(bus); + + if (bus->state == BUS_CLOSING) + return 1; + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + if (bus->state == BUS_WATCH_BIND) { + assert(bus->inotify_fd >= 0); + + p[0].events = POLLIN; + p[0].fd = bus->inotify_fd; + n = 1; + } else { + int e; + + e = sd_bus_get_events(bus); + if (e < 0) + return e; + + if (need_more) + /* The caller really needs some more data, they don't + * care about what's already read, or any timeouts + * except its own. */ + e |= POLLIN; + else { + usec_t until; + /* The caller wants to process if there's something to + * process, but doesn't care otherwise */ + + r = sd_bus_get_timeout(bus, &until); + if (r < 0) + return r; + if (r > 0) + m = usec_sub_unsigned(until, now(CLOCK_MONOTONIC)); + } + + p[0].fd = bus->input_fd; + if (bus->output_fd == bus->input_fd) { + p[0].events = e; + n = 1; + } else { + p[0].events = e & POLLIN; + p[1].fd = bus->output_fd; + p[1].events = e & POLLOUT; + n = 2; + } + } + + if (timeout_usec != UINT64_MAX && (m == USEC_INFINITY || timeout_usec < m)) + m = timeout_usec; + + r = ppoll_usec(p, n, m); + if (r <= 0) + return r; + + return 1; +} + +_public_ int sd_bus_wait(sd_bus *bus, uint64_t timeout_usec) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (bus->state == BUS_CLOSING) + return 0; + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + if (bus->rqueue_size > 0) + return 0; + + r = bus_poll(bus, false, timeout_usec); + if (ERRNO_IS_NEG_TRANSIENT(r)) + return 1; /* treat EINTR as success, but let's exit, so that the caller will call back into us soon. */ + + return r; +} + +_public_ int sd_bus_flush(sd_bus *bus) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (bus->state == BUS_CLOSING) + return 0; + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + /* We never were connected? Don't hang in inotify for good, as there's no timeout set for it */ + if (bus->state == BUS_WATCH_BIND) + return -EUNATCH; + + r = bus_ensure_running(bus); + if (r < 0) + return r; + + if (bus->wqueue_size <= 0) + return 0; + + for (;;) { + r = dispatch_wqueue(bus); + if (ERRNO_IS_NEG_DISCONNECT(r)) { + bus_enter_closing(bus); + return -ECONNRESET; + } else if (r < 0) + return r; + + if (bus->wqueue_size <= 0) + return 0; + + r = bus_poll(bus, false, UINT64_MAX); + if (ERRNO_IS_NEG_TRANSIENT(r)) + continue; + if (r < 0) + return r; + } +} + +_public_ int sd_bus_add_filter( + sd_bus *bus, + sd_bus_slot **slot, + sd_bus_message_handler_t callback, + void *userdata) { + + sd_bus_slot *s; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(callback, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + s = bus_slot_allocate(bus, !slot, BUS_FILTER_CALLBACK, sizeof(struct filter_callback), userdata); + if (!s) + return -ENOMEM; + + s->filter_callback.callback = callback; + + bus->filter_callbacks_modified = true; + LIST_PREPEND(callbacks, bus->filter_callbacks, &s->filter_callback); + + if (slot) + *slot = s; + + return 0; +} + +static int add_match_callback( + sd_bus_message *m, + void *userdata, + sd_bus_error *ret_error) { + + sd_bus_slot *match_slot = ASSERT_PTR(userdata); + bool failed = false; + int r; + + assert(m); + + sd_bus_slot_ref(match_slot); + + if (sd_bus_message_is_method_error(m, NULL)) { + log_debug_errno(sd_bus_message_get_errno(m), + "Unable to add match %s, failing connection: %s", + match_slot->match_callback.match_string, + sd_bus_message_get_error(m)->message); + + failed = true; + } else + log_debug("Match %s successfully installed.", match_slot->match_callback.match_string); + + if (match_slot->match_callback.install_callback) { + sd_bus *bus; + + bus = sd_bus_message_get_bus(m); + + /* This function has been called as slot handler, and we want to call another slot handler. Let's + * update the slot callback metadata temporarily with our own data, and then revert back to the old + * values. */ + + assert(bus->current_slot == match_slot->match_callback.install_slot); + assert(bus->current_handler == add_match_callback); + assert(bus->current_userdata == userdata); + + bus->current_slot = match_slot; + bus->current_handler = match_slot->match_callback.install_callback; + bus->current_userdata = match_slot->userdata; + + r = match_slot->match_callback.install_callback(m, match_slot->userdata, ret_error); + + bus->current_slot = match_slot->match_callback.install_slot; + bus->current_handler = add_match_callback; + bus->current_userdata = userdata; + } else { + if (failed) /* Generic failure handling: destroy the connection */ + bus_enter_closing(sd_bus_message_get_bus(m)); + + r = 1; + } + + /* We don't need the install method reply slot anymore, let's free it */ + match_slot->match_callback.install_slot = sd_bus_slot_unref(match_slot->match_callback.install_slot); + + if (failed && match_slot->floating) + bus_slot_disconnect(match_slot, true); + + sd_bus_slot_unref(match_slot); + + return r; +} + +int bus_add_match_full( + sd_bus *bus, + sd_bus_slot **slot, + bool asynchronous, + const char *match, + sd_bus_message_handler_t callback, + sd_bus_message_handler_t install_callback, + void *userdata, + uint64_t timeout_usec) { + + struct bus_match_component *components = NULL; + size_t n_components = 0; + _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *s = NULL; + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(match, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + CLEANUP_ARRAY(components, n_components, bus_match_parse_free); + + r = bus_match_parse(match, &components, &n_components); + if (r < 0) + return r; + + s = bus_slot_allocate(bus, !slot, BUS_MATCH_CALLBACK, sizeof(struct match_callback), userdata); + if (!s) + return -ENOMEM; + + s->match_callback.callback = callback; + s->match_callback.install_callback = install_callback; + + if (bus->bus_client) { + enum bus_match_scope scope; + + scope = bus_match_get_scope(components, n_components); + + /* Do not install server-side matches for matches against the local service, interface or bus path. */ + if (scope != BUS_MATCH_LOCAL) { + + /* We store the original match string, so that we can use it to remove the match again. */ + + s->match_callback.match_string = strdup(match); + if (!s->match_callback.match_string) + return -ENOMEM; + + if (asynchronous) { + r = bus_add_match_internal_async(bus, + &s->match_callback.install_slot, + s->match_callback.match_string, + add_match_callback, + s, + timeout_usec); + + if (r < 0) + return r; + + /* Make the slot of the match call floating now. We need the reference, but we don't + * want that this match pins the bus object, hence we first create it non-floating, but + * then make it floating. */ + r = sd_bus_slot_set_floating(s->match_callback.install_slot, true); + } else + r = bus_add_match_internal(bus, + s->match_callback.match_string, + timeout_usec, + &s->match_callback.after); + if (r < 0) + return r; + + s->match_added = true; + } + } + + bus->match_callbacks_modified = true; + r = bus_match_add(&bus->match_callbacks, components, n_components, &s->match_callback); + if (r < 0) + return r; + + if (slot) + *slot = s; + s = NULL; + + return 0; +} + +_public_ int sd_bus_add_match( + sd_bus *bus, + sd_bus_slot **slot, + const char *match, + sd_bus_message_handler_t callback, + void *userdata) { + + return bus_add_match_full(bus, slot, false, match, callback, NULL, userdata, 0); +} + +_public_ int sd_bus_add_match_async( + sd_bus *bus, + sd_bus_slot **slot, + const char *match, + sd_bus_message_handler_t callback, + sd_bus_message_handler_t install_callback, + void *userdata) { + + return bus_add_match_full(bus, slot, true, match, callback, install_callback, userdata, 0); +} + +static int io_callback(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + sd_bus *bus = ASSERT_PTR(userdata); + int r; + + /* Note that this is called both on input_fd, output_fd as well as inotify_fd events */ + + r = sd_bus_process(bus, NULL); + if (r < 0) { + log_debug_errno(r, "Processing of bus failed, closing down: %m"); + bus_enter_closing(bus); + } + + return 1; +} + +static int time_callback(sd_event_source *s, uint64_t usec, void *userdata) { + sd_bus *bus = ASSERT_PTR(userdata); + int r; + + r = sd_bus_process(bus, NULL); + if (r < 0) { + log_debug_errno(r, "Processing of bus failed, closing down: %m"); + bus_enter_closing(bus); + } + + return 1; +} + +static int prepare_callback(sd_event_source *s, void *userdata) { + sd_bus *bus = ASSERT_PTR(userdata); + int r, e; + usec_t until; + + assert(s); + + e = sd_bus_get_events(bus); + if (e < 0) { + r = e; + goto fail; + } + + if (bus->output_fd != bus->input_fd) { + + r = sd_event_source_set_io_events(bus->input_io_event_source, e & POLLIN); + if (r < 0) + goto fail; + + r = sd_event_source_set_io_events(bus->output_io_event_source, e & POLLOUT); + } else + r = sd_event_source_set_io_events(bus->input_io_event_source, e); + if (r < 0) + goto fail; + + r = sd_bus_get_timeout(bus, &until); + if (r < 0) + goto fail; + if (r > 0) { + int j; + + j = sd_event_source_set_time(bus->time_event_source, until); + if (j < 0) { + r = j; + goto fail; + } + } + + r = sd_event_source_set_enabled(bus->time_event_source, r > 0 ? SD_EVENT_ONESHOT : SD_EVENT_OFF); + if (r < 0) + goto fail; + + return 1; + +fail: + log_debug_errno(r, "Preparing of bus events failed, closing down: %m"); + bus_enter_closing(bus); + + return 1; +} + +static int quit_callback(sd_event_source *event, void *userdata) { + sd_bus *bus = userdata; + + assert(event); + + if (bus->close_on_exit) { + sd_bus_flush(bus); + sd_bus_close(bus); + } + + return 1; +} + +int bus_attach_io_events(sd_bus *bus) { + int r; + + assert(bus); + + if (bus->input_fd < 0) + return 0; + + if (!bus->event) + return 0; + + if (!bus->input_io_event_source) { + r = sd_event_add_io(bus->event, &bus->input_io_event_source, bus->input_fd, 0, io_callback, bus); + if (r < 0) + return r; + + r = sd_event_source_set_prepare(bus->input_io_event_source, prepare_callback); + if (r < 0) + return r; + + r = sd_event_source_set_priority(bus->input_io_event_source, bus->event_priority); + if (r < 0) + return r; + + r = sd_event_source_set_description(bus->input_io_event_source, "bus-input"); + } else + r = sd_event_source_set_io_fd(bus->input_io_event_source, bus->input_fd); + + if (r < 0) + return r; + + if (bus->output_fd != bus->input_fd) { + assert(bus->output_fd >= 0); + + if (!bus->output_io_event_source) { + r = sd_event_add_io(bus->event, &bus->output_io_event_source, bus->output_fd, 0, io_callback, bus); + if (r < 0) + return r; + + r = sd_event_source_set_priority(bus->output_io_event_source, bus->event_priority); + if (r < 0) + return r; + + r = sd_event_source_set_description(bus->input_io_event_source, "bus-output"); + } else + r = sd_event_source_set_io_fd(bus->output_io_event_source, bus->output_fd); + + if (r < 0) + return r; + } + + return 0; +} + +static void bus_detach_io_events(sd_bus *bus) { + assert(bus); + + bus->input_io_event_source = sd_event_source_disable_unref(bus->input_io_event_source); + bus->output_io_event_source = sd_event_source_disable_unref(bus->output_io_event_source); +} + +int bus_attach_inotify_event(sd_bus *bus) { + int r; + + assert(bus); + + if (bus->inotify_fd < 0) + return 0; + + if (!bus->event) + return 0; + + if (!bus->inotify_event_source) { + r = sd_event_add_io(bus->event, &bus->inotify_event_source, bus->inotify_fd, EPOLLIN, io_callback, bus); + if (r < 0) + return r; + + r = sd_event_source_set_priority(bus->inotify_event_source, bus->event_priority); + if (r < 0) + return r; + + r = sd_event_source_set_description(bus->inotify_event_source, "bus-inotify"); + } else + r = sd_event_source_set_io_fd(bus->inotify_event_source, bus->inotify_fd); + if (r < 0) + return r; + + return 0; +} + +_public_ int sd_bus_attach_event(sd_bus *bus, sd_event *event, int priority) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus->event, -EBUSY); + + assert(!bus->input_io_event_source); + assert(!bus->output_io_event_source); + assert(!bus->time_event_source); + + if (event) + bus->event = sd_event_ref(event); + else { + r = sd_event_default(&bus->event); + if (r < 0) + return r; + } + + bus->event_priority = priority; + + r = sd_event_add_time(bus->event, &bus->time_event_source, CLOCK_MONOTONIC, 0, 0, time_callback, bus); + if (r < 0) + goto fail; + + r = sd_event_source_set_priority(bus->time_event_source, priority); + if (r < 0) + goto fail; + + r = sd_event_source_set_description(bus->time_event_source, "bus-time"); + if (r < 0) + goto fail; + + r = sd_event_add_exit(bus->event, &bus->quit_event_source, quit_callback, bus); + if (r < 0) + goto fail; + + r = sd_event_source_set_description(bus->quit_event_source, "bus-exit"); + if (r < 0) + goto fail; + + r = bus_attach_io_events(bus); + if (r < 0) + goto fail; + + r = bus_attach_inotify_event(bus); + if (r < 0) + goto fail; + + return 0; + +fail: + sd_bus_detach_event(bus); + return r; +} + +_public_ int sd_bus_detach_event(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + + if (!bus->event) + return 0; + + bus_detach_io_events(bus); + bus->inotify_event_source = sd_event_source_disable_unref(bus->inotify_event_source); + bus->time_event_source = sd_event_source_disable_unref(bus->time_event_source); + bus->quit_event_source = sd_event_source_disable_unref(bus->quit_event_source); + + bus->event = sd_event_unref(bus->event); + return 1; +} + +_public_ sd_event* sd_bus_get_event(sd_bus *bus) { + assert_return(bus = bus_resolve(bus), NULL); + + return bus->event; +} + +_public_ sd_bus_message* sd_bus_get_current_message(sd_bus *bus) { + assert_return(bus = bus_resolve(bus), NULL); + + return bus->current_message; +} + +_public_ sd_bus_slot* sd_bus_get_current_slot(sd_bus *bus) { + assert_return(bus = bus_resolve(bus), NULL); + + return bus->current_slot; +} + +_public_ sd_bus_message_handler_t sd_bus_get_current_handler(sd_bus *bus) { + assert_return(bus = bus_resolve(bus), NULL); + + return bus->current_handler; +} + +_public_ void* sd_bus_get_current_userdata(sd_bus *bus) { + assert_return(bus = bus_resolve(bus), NULL); + + return bus->current_userdata; +} + +static int bus_default(int (*bus_open)(sd_bus **), sd_bus **default_bus, sd_bus **ret) { + sd_bus *b = NULL; + int r; + + assert(bus_open); + assert(default_bus); + + if (!ret) + return !!*default_bus; + + if (*default_bus) { + *ret = sd_bus_ref(*default_bus); + return 0; + } + + r = bus_open(&b); + if (r < 0) + return r; + + b->default_bus_ptr = default_bus; + b->tid = gettid(); + *default_bus = b; + + *ret = b; + return 1; +} + +_public_ int sd_bus_default_system(sd_bus **ret) { + return bus_default(sd_bus_open_system, &default_system_bus, ret); +} + +_public_ int sd_bus_default_user(sd_bus **ret) { + return bus_default(sd_bus_open_user, &default_user_bus, ret); +} + +_public_ int sd_bus_default(sd_bus **ret) { + int (*bus_open)(sd_bus **) = NULL; + sd_bus **busp; + + busp = bus_choose_default(&bus_open); + return bus_default(bus_open, busp, ret); +} + +_public_ int sd_bus_get_tid(sd_bus *b, pid_t *tid) { + assert_return(b, -EINVAL); + assert_return(tid, -EINVAL); + assert_return(!bus_origin_changed(b), -ECHILD); + + if (b->tid != 0) { + *tid = b->tid; + return 0; + } + + if (b->event) + return sd_event_get_tid(b->event, tid); + + return -ENXIO; +} + +_public_ int sd_bus_path_encode(const char *prefix, const char *external_id, char **ret_path) { + _cleanup_free_ char *e = NULL; + char *ret; + + assert_return(object_path_is_valid(prefix), -EINVAL); + assert_return(external_id, -EINVAL); + assert_return(ret_path, -EINVAL); + + e = bus_label_escape(external_id); + if (!e) + return -ENOMEM; + + ret = path_join(prefix, e); + if (!ret) + return -ENOMEM; + + *ret_path = ret; + return 0; +} + +_public_ int sd_bus_path_decode(const char *path, const char *prefix, char **external_id) { + const char *e; + char *ret; + + assert_return(object_path_is_valid(path), -EINVAL); + assert_return(object_path_is_valid(prefix), -EINVAL); + assert_return(external_id, -EINVAL); + + e = object_path_startswith(path, prefix); + if (!e) { + *external_id = NULL; + return 0; + } + + /* Note that 'e' might be an empty string here. That's expected. E.g. a case where the subtree + * corresponds to a subtree on a disk, and we want to return something that represents the root + * of the filesystem. */ + + ret = bus_label_unescape(e); + if (!ret) + return -ENOMEM; + + *external_id = ret; + return 1; +} + +_public_ int sd_bus_path_encode_many(char **out, const char *path_template, ...) { + _cleanup_strv_free_ char **labels = NULL; + char *path, *path_pos, **label_pos; + const char *sep, *template_pos; + size_t path_length; + va_list list; + int r; + + assert_return(out, -EINVAL); + assert_return(path_template, -EINVAL); + + path_length = strlen(path_template); + + va_start(list, path_template); + for (sep = strchr(path_template, '%'); sep; sep = strchr(sep + 1, '%')) { + const char *arg; + char *label; + + arg = va_arg(list, const char *); + if (!arg) { + va_end(list); + return -EINVAL; + } + + label = bus_label_escape(arg); + if (!label) { + va_end(list); + return -ENOMEM; + } + + r = strv_consume(&labels, label); + if (r < 0) { + va_end(list); + return r; + } + + /* add label length, but account for the format character */ + path_length += strlen(label) - 1; + } + va_end(list); + + path = malloc(path_length + 1); + if (!path) + return -ENOMEM; + + path_pos = path; + label_pos = labels; + + for (template_pos = path_template; *template_pos; ) { + sep = strchrnul(template_pos, '%'); + path_pos = mempcpy(path_pos, template_pos, sep - template_pos); + if (!*sep) + break; + + path_pos = stpcpy(path_pos, *label_pos++); + template_pos = sep + 1; + } + + *path_pos = 0; + *out = path; + return 0; +} + +_public_ int sd_bus_path_decode_many(const char *path, const char *path_template, ...) { + _cleanup_strv_free_ char **labels = NULL; + const char *template_pos, *path_pos; + char **label_pos; + va_list list; + int r; + + /* + * This decodes an object-path based on a template argument. The + * template consists of a verbatim path, optionally including special + * directives: + * + * - Each occurrence of '%' in the template matches an arbitrary + * substring of a label in the given path. At most one such + * directive is allowed per label. For each such directive, the + * caller must provide an output parameter (char **) via va_arg. If + * NULL is passed, the given label is verified, but not returned. + * For each matched label, the *decoded* label is stored in the + * passed output argument, and the caller is responsible to free + * it. Note that the output arguments are only modified if the + * actually path matched the template. Otherwise, they're left + * untouched. + * + * This function returns <0 on error, 0 if the path does not match the + * template, 1 if it matched. + */ + + assert_return(path, -EINVAL); + assert_return(path_template, -EINVAL); + + path_pos = path; + + for (template_pos = path_template; *template_pos; ) { + const char *sep; + size_t length; + char *label; + + /* verify everything until the next '%' matches verbatim */ + sep = strchrnul(template_pos, '%'); + length = sep - template_pos; + if (strncmp(path_pos, template_pos, length)) + return 0; + + path_pos += length; + template_pos += length; + + if (!*template_pos) + break; + + /* We found the next '%' character. Everything up until here + * matched. We now skip ahead to the end of this label and make + * sure it matches the tail of the label in the path. Then we + * decode the string in-between and save it for later use. */ + + ++template_pos; /* skip over '%' */ + + sep = strchrnul(template_pos, '/'); + length = sep - template_pos; /* length of suffix to match verbatim */ + + /* verify the suffixes match */ + sep = strchrnul(path_pos, '/'); + if (sep - path_pos < (ssize_t)length || + strncmp(sep - length, template_pos, length)) + return 0; + + template_pos += length; /* skip over matched label */ + length = sep - path_pos - length; /* length of sub-label to decode */ + + /* store unescaped label for later use */ + label = bus_label_unescape_n(path_pos, length); + if (!label) + return -ENOMEM; + + r = strv_consume(&labels, label); + if (r < 0) + return r; + + path_pos = sep; /* skip decoded label and suffix */ + } + + /* end of template must match end of path */ + if (*path_pos) + return 0; + + /* copy the labels over to the caller */ + va_start(list, path_template); + for (label_pos = labels; label_pos && *label_pos; ++label_pos) { + char **arg; + + arg = va_arg(list, char **); + if (arg) + *arg = *label_pos; + else + free(*label_pos); + } + va_end(list); + + labels = mfree(labels); + return 1; +} + +_public_ int sd_bus_try_close(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return -EOPNOTSUPP; +} + +_public_ int sd_bus_get_description(sd_bus *bus, const char **description) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(description, -EINVAL); + + const char *d = bus->description; + if (!d) + d = runtime_scope_to_string(bus->runtime_scope); + if (!d) + return -ENXIO; + + *description = d; + return 0; +} + +_public_ int sd_bus_get_scope(sd_bus *bus, const char **scope) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(scope, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (bus->runtime_scope < 0) + return -ENODATA; + + *scope = runtime_scope_to_string(bus->runtime_scope); + return 0; +} + +_public_ int sd_bus_get_address(sd_bus *bus, const char **address) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(address, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (bus->address) { + *address = bus->address; + return 0; + } + + return -ENODATA; +} + +_public_ int sd_bus_get_creds_mask(sd_bus *bus, uint64_t *mask) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(mask, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + *mask = bus->creds_mask; + return 0; +} + +_public_ int sd_bus_is_bus_client(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->bus_client; +} + +_public_ int sd_bus_is_server(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->is_server; +} + +_public_ int sd_bus_is_anonymous(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->anonymous_auth; +} + +_public_ int sd_bus_is_trusted(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->trusted; +} + +_public_ int sd_bus_is_monitor(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + + return bus->is_monitor; +} + +static void flush_close(sd_bus *bus) { + if (!bus) + return; + + /* Flushes and closes the specified bus. We take a ref before, + * to ensure the flushing does not cause the bus to be + * unreferenced. */ + + sd_bus_flush_close_unref(sd_bus_ref(bus)); +} + +_public_ void sd_bus_default_flush_close(void) { + flush_close(default_starter_bus); + flush_close(default_user_bus); + flush_close(default_system_bus); +} + +_public_ int sd_bus_set_exit_on_disconnect(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + + /* Turns on exit-on-disconnect, and triggers it immediately if the bus connection was already + * disconnected. Note that this is triggered exclusively on disconnections triggered by the server side, never + * from the client side. */ + bus->exit_on_disconnect = b; + + /* If the exit condition was triggered already, exit immediately. */ + return bus_exit_now(bus, /* event= */ NULL); +} + +_public_ int sd_bus_get_exit_on_disconnect(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + + return bus->exit_on_disconnect; +} + +_public_ int sd_bus_set_sender(sd_bus *bus, const char *sender) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus->bus_client, -EPERM); + assert_return(!sender || service_name_is_valid(sender), -EINVAL); + + return free_and_strdup(&bus->patch_sender, sender); +} + +_public_ int sd_bus_get_sender(sd_bus *bus, const char **ret) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(ret, -EINVAL); + + if (!bus->patch_sender) + return -ENODATA; + + *ret = bus->patch_sender; + return 0; +} + +_public_ int sd_bus_get_n_queued_read(sd_bus *bus, uint64_t *ret) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + assert_return(ret, -EINVAL); + + *ret = bus->rqueue_size; + return 0; +} + +_public_ int sd_bus_get_n_queued_write(sd_bus *bus, uint64_t *ret) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(!bus_origin_changed(bus), -ECHILD); + assert_return(ret, -EINVAL); + + *ret = bus->wqueue_size; + return 0; +} + +_public_ int sd_bus_set_method_call_timeout(sd_bus *bus, uint64_t usec) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + + bus->method_call_timeout = usec; + return 0; +} + +_public_ int sd_bus_get_method_call_timeout(sd_bus *bus, uint64_t *ret) { + const char *e; + usec_t usec; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(ret, -EINVAL); + + if (bus->method_call_timeout != 0) { + *ret = bus->method_call_timeout; + return 0; + } + + e = secure_getenv("SYSTEMD_BUS_TIMEOUT"); + if (e && parse_sec(e, &usec) >= 0 && usec != 0) { + /* Save the parsed value to avoid multiple parsing. To change the timeout value, + * use sd_bus_set_method_call_timeout() instead of setenv(). */ + *ret = bus->method_call_timeout = usec; + return 0; + } + + *ret = bus->method_call_timeout = BUS_DEFAULT_TIMEOUT; + return 0; +} + +_public_ int sd_bus_set_close_on_exit(sd_bus *bus, int b) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + + bus->close_on_exit = b; + return 0; +} + +_public_ int sd_bus_get_close_on_exit(sd_bus *bus) { + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + + return bus->close_on_exit; +} + +_public_ int sd_bus_enqueue_for_read(sd_bus *bus, sd_bus_message *m) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(m, -EINVAL); + assert_return(m->sealed, -EINVAL); + assert_return(!bus_origin_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + /* Re-enqueue a message for reading. This is primarily useful for PolicyKit-style authentication, + * where we accept a message, then determine we need to interactively authenticate the user, and then + * we want to process the message again. */ + + r = bus_rqueue_make_room(bus); + if (r < 0) + return r; + + bus->rqueue[bus->rqueue_size++] = bus_message_ref_queued(m, bus); + return 0; +} |