diff options
Diffstat (limited to 'src/libsystemd/sd-bus/bus-internal.h')
-rw-r--r-- | src/libsystemd/sd-bus/bus-internal.h | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/src/libsystemd/sd-bus/bus-internal.h b/src/libsystemd/sd-bus/bus-internal.h new file mode 100644 index 0000000..233a228 --- /dev/null +++ b/src/libsystemd/sd-bus/bus-internal.h @@ -0,0 +1,416 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +#pragma once + +#include <pthread.h> + +#include "sd-bus.h" + +#include "bus-error.h" +#include "bus-kernel.h" +#include "bus-match.h" +#include "def.h" +#include "hashmap.h" +#include "list.h" +#include "prioq.h" +#include "socket-util.h" +#include "time-util.h" + +/* Note that we use the new /run prefix here (instead of /var/run) since we require them to be aliases and + * that way we become independent of /var being mounted */ +#define DEFAULT_SYSTEM_BUS_ADDRESS "unix:path=/run/dbus/system_bus_socket" +#define DEFAULT_USER_BUS_ADDRESS_FMT "unix:path=%s/bus" + +struct reply_callback { + sd_bus_message_handler_t callback; + usec_t timeout_usec; /* this is a relative timeout until we reach the BUS_HELLO state, and an absolute one right after */ + uint64_t cookie; + unsigned prioq_idx; +}; + +struct filter_callback { + sd_bus_message_handler_t callback; + + unsigned last_iteration; + + LIST_FIELDS(struct filter_callback, callbacks); +}; + +struct match_callback { + sd_bus_message_handler_t callback; + sd_bus_message_handler_t install_callback; + + sd_bus_slot *install_slot; /* The AddMatch() call */ + + unsigned last_iteration; + + /* Don't dispatch this slot with messages that arrived in any iteration before or at the this + * one. We use this to ensure that matches don't apply "retroactively" and thus can confuse the + * caller: matches will only match incoming messages from the moment on the match was installed. */ + uint64_t after; + + char *match_string; + + struct bus_match_node *match_node; +}; + +struct node { + char *path; + struct node *parent; + LIST_HEAD(struct node, child); + LIST_FIELDS(struct node, siblings); + + LIST_HEAD(struct node_callback, callbacks); + LIST_HEAD(struct node_vtable, vtables); + LIST_HEAD(struct node_enumerator, enumerators); + LIST_HEAD(struct node_object_manager, object_managers); +}; + +struct node_callback { + struct node *node; + + bool is_fallback:1; + unsigned last_iteration; + + sd_bus_message_handler_t callback; + + LIST_FIELDS(struct node_callback, callbacks); +}; + +struct node_enumerator { + struct node *node; + + sd_bus_node_enumerator_t callback; + + unsigned last_iteration; + + LIST_FIELDS(struct node_enumerator, enumerators); +}; + +struct node_object_manager { + struct node *node; + + LIST_FIELDS(struct node_object_manager, object_managers); +}; + +struct node_vtable { + struct node *node; + + bool is_fallback:1; + unsigned last_iteration; + + char *interface; + const sd_bus_vtable *vtable; + sd_bus_object_find_t find; + + LIST_FIELDS(struct node_vtable, vtables); +}; + +struct vtable_member { + const char *path; + const char *interface; + const char *member; + struct node_vtable *parent; + unsigned last_iteration; + const sd_bus_vtable *vtable; +}; + +typedef enum BusSlotType { + BUS_REPLY_CALLBACK, + BUS_FILTER_CALLBACK, + BUS_MATCH_CALLBACK, + BUS_NODE_CALLBACK, + BUS_NODE_ENUMERATOR, + BUS_NODE_VTABLE, + BUS_NODE_OBJECT_MANAGER, + _BUS_SLOT_INVALID = -1, +} BusSlotType; + +struct sd_bus_slot { + unsigned n_ref; + BusSlotType type:5; + + /* Slots can be "floating" or not. If they are not floating (the usual case) then they reference the bus object + * they are associated with. This means the bus object stays allocated at least as long as there is a slot + * around associated with it. If it is floating, then the slot's lifecycle is bound to the lifecycle of the + * bus: it will be disconnected from the bus when the bus is destroyed, and it keeping the slot reffed hence + * won't mean the bus stays reffed too. Internally this means the reference direction is reversed: floating + * slots objects are referenced by the bus object, and not vice versa. */ + bool floating:1; + + bool match_added:1; + + sd_bus *bus; + void *userdata; + sd_bus_destroy_t destroy_callback; + + char *description; + + LIST_FIELDS(sd_bus_slot, slots); + + union { + struct reply_callback reply_callback; + struct filter_callback filter_callback; + struct match_callback match_callback; + struct node_callback node_callback; + struct node_enumerator node_enumerator; + struct node_object_manager node_object_manager; + struct node_vtable node_vtable; + }; +}; + +enum bus_state { + BUS_UNSET, + BUS_WATCH_BIND, /* waiting for the socket to appear via inotify */ + BUS_OPENING, /* the kernel's connect() is still not ready */ + BUS_AUTHENTICATING, /* we are currently in the "SASL" authorization phase of dbus */ + BUS_HELLO, /* we are waiting for the Hello() response */ + BUS_RUNNING, + BUS_CLOSING, + BUS_CLOSED, + _BUS_STATE_MAX, +}; + +static inline bool BUS_IS_OPEN(enum bus_state state) { + return state > BUS_UNSET && state < BUS_CLOSING; +} + +enum bus_auth { + _BUS_AUTH_INVALID, + BUS_AUTH_EXTERNAL, + BUS_AUTH_ANONYMOUS +}; + +struct sd_bus { + unsigned n_ref; + + enum bus_state state; + int input_fd, output_fd; + int inotify_fd; + int message_version; + int message_endian; + + bool can_fds:1; + bool bus_client:1; + bool ucred_valid:1; + bool is_server:1; + bool anonymous_auth:1; + bool prefer_readv:1; + bool prefer_writev:1; + bool match_callbacks_modified:1; + bool filter_callbacks_modified:1; + bool nodes_modified:1; + bool trusted:1; + bool manual_peer_interface:1; + bool is_system:1; + bool is_user:1; + bool allow_interactive_authorization:1; + bool exit_on_disconnect:1; + bool exited:1; + bool exit_triggered:1; + bool is_local:1; + bool watch_bind:1; + bool is_monitor:1; + bool accept_fd:1; + bool attach_timestamp:1; + bool connected_signal:1; + bool close_on_exit:1; + + signed int use_memfd:2; + + void *rbuffer; + size_t rbuffer_size; + + sd_bus_message **rqueue; + size_t rqueue_size; + size_t rqueue_allocated; + + sd_bus_message **wqueue; + size_t wqueue_size; + size_t windex; + size_t wqueue_allocated; + + uint64_t cookie; + uint64_t read_counter; /* A counter for each incoming msg */ + + char *unique_name; + uint64_t unique_id; + + struct bus_match_node match_callbacks; + Prioq *reply_callbacks_prioq; + OrderedHashmap *reply_callbacks; + LIST_HEAD(struct filter_callback, filter_callbacks); + + Hashmap *nodes; + Hashmap *vtable_methods; + Hashmap *vtable_properties; + + union sockaddr_union sockaddr; + socklen_t sockaddr_size; + + pid_t nspid; + char *machine; + + sd_id128_t server_id; + + char *address; + unsigned address_index; + + int last_connect_error; + + enum bus_auth auth; + unsigned auth_index; + struct iovec auth_iovec[3]; + size_t auth_rbegin; + char *auth_buffer; + usec_t auth_timeout; + + struct ucred ucred; + char *label; + gid_t *groups; + size_t n_groups; + + uint64_t creds_mask; + + int *fds; + size_t n_fds; + + char *exec_path; + char **exec_argv; + + /* We do locking around the memfd cache, since we want to + * allow people to process a sd_bus_message in a different + * thread then it was generated on and free it there. Since + * adding something to the memfd cache might happen when a + * message is released, we hence need to protect this bit with + * a mutex. */ + pthread_mutex_t memfd_cache_mutex; + struct memfd_cache memfd_cache[MEMFD_CACHE_MAX]; + unsigned n_memfd_cache; + + pid_t original_pid; + pid_t busexec_pid; + + unsigned iteration_counter; + + sd_event_source *input_io_event_source; + sd_event_source *output_io_event_source; + sd_event_source *time_event_source; + sd_event_source *quit_event_source; + sd_event_source *inotify_event_source; + sd_event *event; + int event_priority; + + pid_t tid; + + sd_bus_message *current_message; + sd_bus_slot *current_slot; + sd_bus_message_handler_t current_handler; + void *current_userdata; + + sd_bus **default_bus_ptr; + + char *description; + char *patch_sender; + + sd_bus_track *track_queue; + + LIST_HEAD(sd_bus_slot, slots); + LIST_HEAD(sd_bus_track, tracks); + + int *inotify_watches; + size_t n_inotify_watches; + + /* zero means use value specified by $SYSTEMD_BUS_TIMEOUT= environment variable or built-in default */ + usec_t method_call_timeout; +}; + +/* For method calls we timeout at 25s, like in the D-Bus reference implementation */ +#define BUS_DEFAULT_TIMEOUT ((usec_t) (25 * USEC_PER_SEC)) + +/* For the authentication phase we grant 90s, to provide extra room during boot, when RNGs and such are not filled up + * with enough entropy yet and might delay the boot */ +#define BUS_AUTH_TIMEOUT ((usec_t) DEFAULT_TIMEOUT_USEC) + +#define BUS_WQUEUE_MAX (384*1024) +#define BUS_RQUEUE_MAX (384*1024) + +#define BUS_MESSAGE_SIZE_MAX (128*1024*1024) +#define BUS_AUTH_SIZE_MAX (64*1024) +/* Note that the D-Bus specification states that bus paths shall have no size limit. We enforce here one + * anyway, since truly unbounded strings are a security problem. The limit we pick is relatively large however, + * to not clash unnecessarily with real-life applications. */ +#define BUS_PATH_SIZE_MAX (64*1024) + +#define BUS_CONTAINER_DEPTH 128 + +/* Defined by the specification as maximum size of an array in bytes */ +#define BUS_ARRAY_MAX_SIZE 67108864 + +#define BUS_FDS_MAX 1024 + +#define BUS_EXEC_ARGV_MAX 256 + +bool interface_name_is_valid(const char *p) _pure_; +bool service_name_is_valid(const char *p) _pure_; +bool member_name_is_valid(const char *p) _pure_; +bool object_path_is_valid(const char *p) _pure_; + +char *object_path_startswith(const char *a, const char *b) _pure_; + +bool namespace_complex_pattern(const char *pattern, const char *value) _pure_; +bool path_complex_pattern(const char *pattern, const char *value) _pure_; + +bool namespace_simple_pattern(const char *pattern, const char *value) _pure_; +bool path_simple_pattern(const char *pattern, const char *value) _pure_; + +int bus_message_type_from_string(const char *s, uint8_t *u) _pure_; +const char *bus_message_type_to_string(uint8_t u) _pure_; + +#define error_name_is_valid interface_name_is_valid + +sd_bus *bus_resolve(sd_bus *bus); + +int bus_ensure_running(sd_bus *bus); +int bus_start_running(sd_bus *bus); +int bus_next_address(sd_bus *bus); + +int bus_seal_synthetic_message(sd_bus *b, sd_bus_message *m); + +int bus_rqueue_make_room(sd_bus *bus); + +bool bus_pid_changed(sd_bus *bus); + +char *bus_address_escape(const char *v); + +int bus_attach_io_events(sd_bus *b); +int bus_attach_inotify_event(sd_bus *b); + +void bus_close_inotify_fd(sd_bus *b); +void bus_close_io_fds(sd_bus *b); + +#define OBJECT_PATH_FOREACH_PREFIX(prefix, path) \ + for (char *_slash = ({ strcpy((prefix), (path)); streq((prefix), "/") ? NULL : strrchr((prefix), '/'); }) ; \ + _slash && ((_slash[(_slash) == (prefix)] = 0), true); \ + _slash = streq((prefix), "/") ? NULL : strrchr((prefix), '/')) + +/* If we are invoking callbacks of a bus object, ensure unreffing the + * bus from the callback doesn't destroy the object we are working on */ +#define BUS_DONT_DESTROY(bus) \ + _cleanup_(sd_bus_unrefp) _unused_ sd_bus *_dont_destroy_##bus = sd_bus_ref(bus) + +int bus_set_address_system(sd_bus *bus); +int bus_set_address_user(sd_bus *bus); +int bus_set_address_system_remote(sd_bus *b, const char *host); +int bus_set_address_system_machine(sd_bus *b, const char *machine); + +int bus_maybe_reply_error(sd_bus_message *m, int r, sd_bus_error *error); + +#define bus_assert_return(expr, r, error) \ + do { \ + if (!assert_log(expr, #expr)) \ + return sd_bus_error_set_errno(error, r); \ + } while (false) + +void bus_enter_closing(sd_bus *bus); + +void bus_set_state(sd_bus *bus, enum bus_state state); |