src/libsystemd/sd-bus/bus-internal.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2013 Lennart Poettering
   8 ***/
   9
  10 #include <pthread.h>
  11 #include <sys/socket.h>
  12
  13 #include "sd-bus.h"
  14
  15 #include "bus-error.h"
  16 #include "bus-kernel.h"
  17 #include "bus-match.h"
  18 #include "def.h"
  19 #include "hashmap.h"
  20 #include "list.h"
  21 #include "prioq.h"
  22 #include "refcnt.h"
  23 #include "socket-util.h"
  24 #include "util.h"
  25
  26 struct reply_callback {
  27         sd_bus_message_handler_t callback;
  28         usec_t timeout_usec; /* this is a relative timeout until we reach the BUS_HELLO state, and an absolute one right after */
  29         uint64_t cookie;
  30         unsigned prioq_idx;
  31 };
  32
  33 struct filter_callback {
  34         sd_bus_message_handler_t callback;
  35
  36         unsigned last_iteration;
  37
  38         LIST_FIELDS(struct filter_callback, callbacks);
  39 };
  40
  41 struct match_callback {
  42         sd_bus_message_handler_t callback;
  43         sd_bus_message_handler_t install_callback;
  44
  45         sd_bus_slot *install_slot; /* The AddMatch() call */
  46
  47         unsigned last_iteration;
  48
  49         char *match_string;
  50
  51         struct bus_match_node *match_node;
  52 };
  53
  54 struct node {
  55         char *path;
  56         struct node *parent;
  57         LIST_HEAD(struct node, child);
  58         LIST_FIELDS(struct node, siblings);
  59
  60         LIST_HEAD(struct node_callback, callbacks);
  61         LIST_HEAD(struct node_vtable, vtables);
  62         LIST_HEAD(struct node_enumerator, enumerators);
  63         LIST_HEAD(struct node_object_manager, object_managers);
  64 };
  65
  66 struct node_callback {
  67         struct node *node;
  68
  69         bool is_fallback;
  70         sd_bus_message_handler_t callback;
  71
  72         unsigned last_iteration;
  73
  74         LIST_FIELDS(struct node_callback, callbacks);
  75 };
  76
  77 struct node_enumerator {
  78         struct node *node;
  79
  80         sd_bus_node_enumerator_t callback;
  81
  82         unsigned last_iteration;
  83
  84         LIST_FIELDS(struct node_enumerator, enumerators);
  85 };
  86
  87 struct node_object_manager {
  88         struct node *node;
  89
  90         LIST_FIELDS(struct node_object_manager, object_managers);
  91 };
  92
  93 struct node_vtable {
  94         struct node *node;
  95
  96         char *interface;
  97         bool is_fallback;
  98         const sd_bus_vtable *vtable;
  99         sd_bus_object_find_t find;
 100
 101         unsigned last_iteration;
 102
 103         LIST_FIELDS(struct node_vtable, vtables);
 104 };
 105
 106 struct vtable_member {
 107         const char *path;
 108         const char *interface;
 109         const char *member;
 110         struct node_vtable *parent;
 111         unsigned last_iteration;
 112         const sd_bus_vtable *vtable;
 113 };
 114
 115 typedef enum BusSlotType {
 116         BUS_REPLY_CALLBACK,
 117         BUS_FILTER_CALLBACK,
 118         BUS_MATCH_CALLBACK,
 119         BUS_NODE_CALLBACK,
 120         BUS_NODE_ENUMERATOR,
 121         BUS_NODE_VTABLE,
 122         BUS_NODE_OBJECT_MANAGER,
 123         _BUS_SLOT_INVALID = -1,
 124 } BusSlotType;
 125
 126 struct sd_bus_slot {
 127         unsigned n_ref;
 128         sd_bus *bus;
 129         void *userdata;
 130         BusSlotType type:5;
 131         bool floating:1;
 132         bool match_added:1;
 133         char *description;
 134
 135         LIST_FIELDS(sd_bus_slot, slots);
 136
 137         union {
 138                 struct reply_callback reply_callback;
 139                 struct filter_callback filter_callback;
 140                 struct match_callback match_callback;
 141                 struct node_callback node_callback;
 142                 struct node_enumerator node_enumerator;
 143                 struct node_object_manager node_object_manager;
 144                 struct node_vtable node_vtable;
 145         };
 146 };
 147
 148 enum bus_state {
 149         BUS_UNSET,
 150         BUS_WATCH_BIND,      /* waiting for the socket to appear via inotify */
 151         BUS_OPENING,         /* the kernel's connect() is still not ready */
 152         BUS_AUTHENTICATING,  /* we are currently in the "SASL" authorization phase of dbus */
 153         BUS_HELLO,           /* we are waiting for the Hello() response */
 154         BUS_RUNNING,
 155         BUS_CLOSING,
 156         BUS_CLOSED,
 157         _BUS_STATE_MAX,
 158 };
 159
 160 static inline bool BUS_IS_OPEN(enum bus_state state) {
 161         return state > BUS_UNSET && state < BUS_CLOSING;
 162 }
 163
 164 enum bus_auth {
 165         _BUS_AUTH_INVALID,
 166         BUS_AUTH_EXTERNAL,
 167         BUS_AUTH_ANONYMOUS
 168 };
 169
 170 struct sd_bus {
 171         /* We use atomic ref counting here since sd_bus_message
 172            objects retain references to their originating sd_bus but
 173            we want to allow them to be processed in a different
 174            thread. We won't provide full thread safety, but only the
 175            bare minimum that makes it possible to use sd_bus and
 176            sd_bus_message objects independently and on different
 177            threads as long as each object is used only once at the
 178            same time. */
 179         RefCount n_ref;
 180
 181         enum bus_state state;
 182         int input_fd, output_fd;
 183         int inotify_fd;
 184         int message_version;
 185         int message_endian;
 186
 187         bool can_fds:1;
 188         bool bus_client:1;
 189         bool ucred_valid:1;
 190         bool is_server:1;
 191         bool anonymous_auth:1;
 192         bool prefer_readv:1;
 193         bool prefer_writev:1;
 194         bool match_callbacks_modified:1;
 195         bool filter_callbacks_modified:1;
 196         bool nodes_modified:1;
 197         bool trusted:1;
 198         bool manual_peer_interface:1;
 199         bool is_system:1;
 200         bool is_user:1;
 201         bool allow_interactive_authorization:1;
 202         bool exit_on_disconnect:1;
 203         bool exited:1;
 204         bool exit_triggered:1;
 205         bool is_local:1;
 206         bool watch_bind:1;
 207         bool is_monitor:1;
 208         bool accept_fd:1;
 209         bool attach_timestamp:1;
 210         bool connected_signal:1;
 211
 212         int use_memfd;
 213
 214         void *rbuffer;
 215         size_t rbuffer_size;
 216
 217         sd_bus_message **rqueue;
 218         unsigned rqueue_size;
 219         size_t rqueue_allocated;
 220
 221         sd_bus_message **wqueue;
 222         unsigned wqueue_size;
 223         size_t windex;
 224         size_t wqueue_allocated;
 225
 226         uint64_t cookie;
 227
 228         char *unique_name;
 229         uint64_t unique_id;
 230
 231         struct bus_match_node match_callbacks;
 232         Prioq *reply_callbacks_prioq;
 233         OrderedHashmap *reply_callbacks;
 234         LIST_HEAD(struct filter_callback, filter_callbacks);
 235
 236         Hashmap *nodes;
 237         Hashmap *vtable_methods;
 238         Hashmap *vtable_properties;
 239
 240         union sockaddr_union sockaddr;
 241         socklen_t sockaddr_size;
 242
 243         char *machine;
 244         pid_t nspid;
 245
 246         sd_id128_t server_id;
 247
 248         char *address;
 249         unsigned address_index;
 250
 251         int last_connect_error;
 252
 253         enum bus_auth auth;
 254         size_t auth_rbegin;
 255         struct iovec auth_iovec[3];
 256         unsigned auth_index;
 257         char *auth_buffer;
 258         usec_t auth_timeout;
 259
 260         struct ucred ucred;
 261         char *label;
 262         gid_t *groups;
 263         size_t n_groups;
 264
 265         uint64_t creds_mask;
 266
 267         int *fds;
 268         unsigned n_fds;
 269
 270         char *exec_path;
 271         char **exec_argv;
 272
 273         unsigned iteration_counter;
 274
 275         /* We do locking around the memfd cache, since we want to
 276          * allow people to process a sd_bus_message in a different
 277          * thread then it was generated on and free it there. Since
 278          * adding something to the memfd cache might happen when a
 279          * message is released, we hence need to protect this bit with
 280          * a mutex. */
 281         pthread_mutex_t memfd_cache_mutex;
 282         struct memfd_cache memfd_cache[MEMFD_CACHE_MAX];
 283         unsigned n_memfd_cache;
 284
 285         pid_t original_pid;
 286         pid_t busexec_pid;
 287
 288         sd_event_source *input_io_event_source;
 289         sd_event_source *output_io_event_source;
 290         sd_event_source *time_event_source;
 291         sd_event_source *quit_event_source;
 292         sd_event_source *inotify_event_source;
 293         sd_event *event;
 294         int event_priority;
 295
 296         sd_bus_message *current_message;
 297         sd_bus_slot *current_slot;
 298         sd_bus_message_handler_t current_handler;
 299         void *current_userdata;
 300
 301         sd_bus **default_bus_ptr;
 302         pid_t tid;
 303
 304         char *cgroup_root;
 305
 306         char *description;
 307         char *patch_sender;
 308
 309         sd_bus_track *track_queue;
 310
 311         LIST_HEAD(sd_bus_slot, slots);
 312         LIST_HEAD(sd_bus_track, tracks);
 313
 314         int *inotify_watches;
 315         size_t n_inotify_watches;
 316 };
 317
 318 /* For method calls we time-out at 25s, like in the D-Bus reference implementation */
 319 #define BUS_DEFAULT_TIMEOUT ((usec_t) (25 * USEC_PER_SEC))
 320
 321 /* For the authentication phase we grant 90s, to provide extra room during boot, when RNGs and such are not filled up
 322  * with enough entropy yet and might delay the boot */
 323 #define BUS_AUTH_TIMEOUT ((usec_t) DEFAULT_TIMEOUT_USEC)
 324
 325 #define BUS_WQUEUE_MAX (192*1024)
 326 #define BUS_RQUEUE_MAX (192*1024)
 327
 328 #define BUS_MESSAGE_SIZE_MAX (64*1024*1024)
 329 #define BUS_AUTH_SIZE_MAX (64*1024)
 330
 331 #define BUS_CONTAINER_DEPTH 128
 332
 333 /* Defined by the specification as maximum size of an array in
 334  * bytes */
 335 #define BUS_ARRAY_MAX_SIZE 67108864
 336
 337 #define BUS_FDS_MAX 1024
 338
 339 #define BUS_EXEC_ARGV_MAX 256
 340
 341 bool interface_name_is_valid(const char *p) _pure_;
 342 bool service_name_is_valid(const char *p) _pure_;
 343 char* service_name_startswith(const char *a, const char *b);
 344 bool member_name_is_valid(const char *p) _pure_;
 345 bool object_path_is_valid(const char *p) _pure_;
 346 char *object_path_startswith(const char *a, const char *b) _pure_;
 347
 348 bool namespace_complex_pattern(const char *pattern, const char *value) _pure_;
 349 bool path_complex_pattern(const char *pattern, const char *value) _pure_;
 350
 351 bool namespace_simple_pattern(const char *pattern, const char *value) _pure_;
 352 bool path_simple_pattern(const char *pattern, const char *value) _pure_;
 353
 354 int bus_message_type_from_string(const char *s, uint8_t *u) _pure_;
 355 const char *bus_message_type_to_string(uint8_t u) _pure_;
 356
 357 #define error_name_is_valid interface_name_is_valid
 358
 359 sd_bus *bus_resolve(sd_bus *bus);
 360
 361 int bus_ensure_running(sd_bus *bus);
 362 int bus_start_running(sd_bus *bus);
 363 int bus_next_address(sd_bus *bus);
 364
 365 int bus_seal_synthetic_message(sd_bus *b, sd_bus_message *m);
 366
 367 int bus_rqueue_make_room(sd_bus *bus);
 368
 369 bool bus_pid_changed(sd_bus *bus);
 370
 371 char *bus_address_escape(const char *v);
 372
 373 int bus_attach_io_events(sd_bus *b);
 374 int bus_attach_inotify_event(sd_bus *b);
 375
 376 void bus_close_inotify_fd(sd_bus *b);
 377 void bus_close_io_fds(sd_bus *b);
 378
 379 #define OBJECT_PATH_FOREACH_PREFIX(prefix, path)                        \
 380         for (char *_slash = ({ strcpy((prefix), (path)); streq((prefix), "/") ? NULL : strrchr((prefix), '/'); }) ; \
 381              _slash && !(_slash[(_slash) == (prefix)] = 0);             \
 382              _slash = streq((prefix), "/") ? NULL : strrchr((prefix), '/'))
 383
 384 /* If we are invoking callbacks of a bus object, ensure unreffing the
 385  * bus from the callback doesn't destroy the object we are working
 386  * on */
 387 #define BUS_DONT_DESTROY(bus) \
 388         _cleanup_(sd_bus_unrefp) _unused_ sd_bus *_dont_destroy_##bus = sd_bus_ref(bus)
 389
 390 int bus_set_address_system(sd_bus *bus);
 391 int bus_set_address_user(sd_bus *bus);
 392 int bus_set_address_system_remote(sd_bus *b, const char *host);
 393 int bus_set_address_system_machine(sd_bus *b, const char *machine);
 394
 395 int bus_get_root_path(sd_bus *bus);
 396
 397 int bus_maybe_reply_error(sd_bus_message *m, int r, sd_bus_error *error);
 398
 399 #define bus_assert_return(expr, r, error)                               \
 400         do {                                                            \
 401                 if (!assert_log(expr, #expr))                           \
 402                         return sd_bus_error_set_errno(error, r);        \
 403         } while (false)
 404
 405 void bus_enter_closing(sd_bus *bus);
 406
 407 void bus_set_state(sd_bus *bus, enum bus_state state);