1 /* SPDX-License-Identifier: LGPL-2.1+ */
5 #include "alloc-util.h"
6 #include "errno-util.h"
10 #include "process-util.h"
12 #include "socket-util.h"
13 #include "string-table.h"
14 #include "string-util.h"
16 #include "time-util.h"
17 #include "umask-util.h"
18 #include "user-util.h"
21 #define VARLINK_DEFAULT_CONNECTIONS_MAX 4096U
22 #define VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX 1024U
24 #define VARLINK_DEFAULT_TIMEOUT_USEC (45U*USEC_PER_SEC)
25 #define VARLINK_BUFFER_MAX (16U*1024U*1024U)
26 #define VARLINK_READ_SIZE (64U*1024U)
28 typedef enum VarlinkState
{
29 /* Client side states */
31 VARLINK_AWAITING_REPLY
,
32 VARLINK_AWAITING_REPLY_MORE
,
35 VARLINK_PROCESSING_REPLY
,
37 /* Server side states */
39 VARLINK_PROCESSING_METHOD
,
40 VARLINK_PROCESSING_METHOD_MORE
,
41 VARLINK_PROCESSING_METHOD_ONEWAY
,
42 VARLINK_PROCESSED_METHOD
,
43 VARLINK_PENDING_METHOD
,
44 VARLINK_PENDING_METHOD_MORE
,
46 /* Common states (only during shutdown) */
47 VARLINK_PENDING_DISCONNECT
,
48 VARLINK_PENDING_TIMEOUT
,
49 VARLINK_PROCESSING_DISCONNECT
,
50 VARLINK_PROCESSING_TIMEOUT
,
51 VARLINK_PROCESSING_FAILURE
,
55 _VARLINK_STATE_INVALID
= -1
58 /* Tests whether we are not yet disconnected. Note that this is true during all states where the connection
59 * is still good for something, and false only when it's dead for good. This means: when we are
60 * asynchronously connecting to a peer and the connect() is still pending, then this will return 'true', as
61 * the connection is still good, and we are likely to be able to properly operate on it soon. */
62 #define VARLINK_STATE_IS_ALIVE(state) \
64 VARLINK_IDLE_CLIENT, \
65 VARLINK_AWAITING_REPLY, \
66 VARLINK_AWAITING_REPLY_MORE, \
69 VARLINK_PROCESSING_REPLY, \
70 VARLINK_IDLE_SERVER, \
71 VARLINK_PROCESSING_METHOD, \
72 VARLINK_PROCESSING_METHOD_MORE, \
73 VARLINK_PROCESSING_METHOD_ONEWAY, \
74 VARLINK_PROCESSED_METHOD, \
75 VARLINK_PENDING_METHOD, \
76 VARLINK_PENDING_METHOD_MORE)
81 VarlinkServer
*server
;
84 bool connecting
; /* This boolean indicates whether the socket fd we are operating on is currently
85 * processing an asynchronous connect(). In that state we watch the socket for
86 * EPOLLOUT, but we refrain from calling read() or write() on the socket as that
87 * will trigger ENOTCONN. Note that this boolean is kept separate from the
88 * VarlinkState above on purpose: while the connect() is still not complete we
89 * already want to allow queuing of messages and similar. Thus it's nice to keep
90 * these two state concepts separate: the VarlinkState encodes what our own view of
91 * the connection is, i.e. whether we think it's a server, a client, and has
92 * something queued already, while 'connecting' tells us a detail about the
93 * transport used below, that should have no effect on how we otherwise accept and
94 * process operations from the user.
96 * Or to say this differently: VARLINK_STATE_IS_ALIVE(state) tells you whether the
97 * connection is good to use, even if it might not be fully connected
98 * yet. connecting=true then informs you that actually we are still connecting, and
99 * the connection is actually not established yet and thus any requests you enqueue
100 * now will still work fine but will be queued only, not sent yet, but that
101 * shouldn't stop you from using the connection, since eventually whatever you queue
104 * Or to say this even differently: 'state' is a high-level ("application layer"
105 * high, if you so will) state, while 'conecting' is a low-level ("transport layer"
106 * low, if you so will) state, and while they are not entirely unrelated and
107 * sometimes propagate effects to each other they are only asynchronously connected
113 char *input_buffer
; /* valid data starts at input_buffer_index, ends at input_buffer_index+input_buffer_size */
114 size_t input_buffer_allocated
;
115 size_t input_buffer_index
;
116 size_t input_buffer_size
;
117 size_t input_buffer_unscanned
;
119 char *output_buffer
; /* valid data starts at output_buffer_index, ends at output_buffer_index+output_buffer_size */
120 size_t output_buffer_allocated
;
121 size_t output_buffer_index
;
122 size_t output_buffer_size
;
124 VarlinkReply reply_callback
;
126 JsonVariant
*current
;
130 bool ucred_acquired
:1;
132 bool write_disconnected
:1;
133 bool read_disconnected
:1;
134 bool prefer_read_write
:1;
144 sd_event_source
*io_event_source
;
145 sd_event_source
*time_event_source
;
146 sd_event_source
*quit_event_source
;
147 sd_event_source
*defer_event_source
;
150 typedef struct VarlinkServerSocket VarlinkServerSocket
;
152 struct VarlinkServerSocket
{
153 VarlinkServer
*server
;
158 sd_event_source
*event_source
;
160 LIST_FIELDS(VarlinkServerSocket
, sockets
);
163 struct VarlinkServer
{
165 VarlinkServerFlags flags
;
167 LIST_HEAD(VarlinkServerSocket
, sockets
);
170 VarlinkConnect connect_callback
;
173 int64_t event_priority
;
175 unsigned n_connections
;
181 unsigned connections_max
;
182 unsigned connections_per_uid_max
;
185 static const char* const varlink_state_table
[_VARLINK_STATE_MAX
] = {
186 [VARLINK_IDLE_CLIENT
] = "idle-client",
187 [VARLINK_AWAITING_REPLY
] = "awaiting-reply",
188 [VARLINK_AWAITING_REPLY_MORE
] = "awaiting-reply-more",
189 [VARLINK_CALLING
] = "calling",
190 [VARLINK_CALLED
] = "called",
191 [VARLINK_PROCESSING_REPLY
] = "processing-reply",
192 [VARLINK_IDLE_SERVER
] = "idle-server",
193 [VARLINK_PROCESSING_METHOD
] = "processing-method",
194 [VARLINK_PROCESSING_METHOD_MORE
] = "processing-method-more",
195 [VARLINK_PROCESSING_METHOD_ONEWAY
] = "processing-method-oneway",
196 [VARLINK_PROCESSED_METHOD
] = "processed-method",
197 [VARLINK_PENDING_METHOD
] = "pending-method",
198 [VARLINK_PENDING_METHOD_MORE
] = "pending-method-more",
199 [VARLINK_PENDING_DISCONNECT
] = "pending-disconnect",
200 [VARLINK_PENDING_TIMEOUT
] = "pending-timeout",
201 [VARLINK_PROCESSING_DISCONNECT
] = "processing-disconnect",
202 [VARLINK_PROCESSING_TIMEOUT
] = "processing-timeout",
203 [VARLINK_PROCESSING_FAILURE
] = "processing-failure",
204 [VARLINK_DISCONNECTED
] = "disconnected",
207 DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(varlink_state
, VarlinkState
);
209 #define varlink_log_errno(v, error, fmt, ...) \
210 log_debug_errno(error, "%s: " fmt, varlink_description(v), ##__VA_ARGS__)
212 #define varlink_log(v, fmt, ...) \
213 log_debug("%s: " fmt, varlink_description(v), ##__VA_ARGS__)
215 #define varlink_server_log_errno(s, error, fmt, ...) \
216 log_debug_errno(error, "%s: " fmt, varlink_server_description(s), ##__VA_ARGS__)
218 #define varlink_server_log(s, fmt, ...) \
219 log_debug("%s: " fmt, varlink_server_description(s), ##__VA_ARGS__)
221 static inline const char *varlink_description(Varlink
*v
) {
222 return strna(v
? v
->description
: NULL
);
225 static inline const char *varlink_server_description(VarlinkServer
*s
) {
226 return strna(s
? s
->description
: NULL
);
229 static void varlink_set_state(Varlink
*v
, VarlinkState state
) {
231 assert(state
>= 0 && state
< _VARLINK_STATE_MAX
);
234 varlink_log(v
, "varlink: setting state %s",
235 varlink_state_to_string(state
));
237 varlink_log(v
, "varlink: changing state %s → %s",
238 varlink_state_to_string(v
->state
),
239 varlink_state_to_string(state
));
244 static int varlink_new(Varlink
**ret
) {
257 .state
= _VARLINK_STATE_INVALID
,
259 .ucred
.uid
= UID_INVALID
,
260 .ucred
.gid
= GID_INVALID
,
262 .timestamp
= USEC_INFINITY
,
263 .timeout
= VARLINK_DEFAULT_TIMEOUT_USEC
270 int varlink_connect_address(Varlink
**ret
, const char *address
) {
271 _cleanup_(varlink_unrefp
) Varlink
*v
= NULL
;
272 union sockaddr_union sockaddr
;
275 assert_return(ret
, -EINVAL
);
276 assert_return(address
, -EINVAL
);
278 r
= sockaddr_un_set_path(&sockaddr
.un
, address
);
286 v
->fd
= socket(AF_UNIX
, SOCK_STREAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
290 v
->fd
= fd_move_above_stdio(v
->fd
);
292 if (connect(v
->fd
, &sockaddr
.sa
, SOCKADDR_UN_LEN(sockaddr
.un
)) < 0) {
293 if (!IN_SET(errno
, EAGAIN
, EINPROGRESS
))
296 v
->connecting
= true; /* We are asynchronously connecting, i.e. the connect() is being
297 * processed in the background. As long as that's the case the socket
298 * is in a special state: it's there, we can poll it for EPOLLOUT, but
299 * if we attempt to write() to it before we see EPOLLOUT we'll get
300 * ENOTCONN (and not EAGAIN, like we would for a normal connected
301 * socket that isn't writable at the moment). Since ENOTCONN on write()
302 * hence can mean two different things (i.e. connection not complete
303 * yet vs. already disconnected again), we store as a boolean whether
304 * we are still in connect(). */
307 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
313 int varlink_connect_fd(Varlink
**ret
, int fd
) {
317 assert_return(ret
, -EINVAL
);
318 assert_return(fd
>= 0, -EBADF
);
320 r
= fd_nonblock(fd
, true);
329 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
331 /* Note that if this function is called we assume the passed socket (if it is one) is already
332 * properly connected, i.e. any asynchronous connect() done on it already completed. Because of that
333 * we'll not set the 'connecting' boolean here, i.e. we don't need to avoid write()ing to the socket
334 * until the connection is fully set up. Behaviour here is hence a bit different from
335 * varlink_connect_address() above, as there we do handle asynchronous connections ourselves and
336 * avoid doing write() on it before we saw EPOLLOUT for the first time. */
342 static void varlink_detach_event_sources(Varlink
*v
) {
345 v
->io_event_source
= sd_event_source_disable_unref(v
->io_event_source
);
346 v
->time_event_source
= sd_event_source_disable_unref(v
->time_event_source
);
347 v
->quit_event_source
= sd_event_source_disable_unref(v
->quit_event_source
);
348 v
->defer_event_source
= sd_event_source_disable_unref(v
->defer_event_source
);
351 static void varlink_clear(Varlink
*v
) {
354 varlink_detach_event_sources(v
);
356 v
->fd
= safe_close(v
->fd
);
358 v
->input_buffer
= mfree(v
->input_buffer
);
359 v
->output_buffer
= mfree(v
->output_buffer
);
361 v
->current
= json_variant_unref(v
->current
);
362 v
->reply
= json_variant_unref(v
->reply
);
364 v
->event
= sd_event_unref(v
->event
);
367 static Varlink
* varlink_destroy(Varlink
*v
) {
371 /* If this is called the server object must already been unreffed here. Why that? because when we
372 * linked up the varlink connection with the server object we took one ref in each direction */
377 free(v
->description
);
381 DEFINE_TRIVIAL_REF_UNREF_FUNC(Varlink
, varlink
, varlink_destroy
);
383 static int varlink_test_disconnect(Varlink
*v
) {
386 /* Tests whether we the the connection has been terminated. We are careful to not stop processing it
387 * prematurely, since we want to handle half-open connections as well as possible and want to flush
388 * out and read data before we close down if we can. */
390 /* Already disconnected? */
391 if (!VARLINK_STATE_IS_ALIVE(v
->state
))
394 /* Wait until connection setup is complete, i.e. until asynchronous connect() completes */
398 /* Still something to write and we can write? Stay around */
399 if (v
->output_buffer_size
> 0 && !v
->write_disconnected
)
402 /* Both sides gone already? Then there's no need to stick around */
403 if (v
->read_disconnected
&& v
->write_disconnected
)
406 /* If we are waiting for incoming data but the read side is shut down, disconnect. */
407 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
) && v
->read_disconnected
)
410 /* Similar, if are a client that hasn't written anything yet but the write side is dead, also
411 * disconnect. We also explicitly check for POLLHUP here since we likely won't notice the write side
412 * being down if we never wrote anything. */
413 if (IN_SET(v
->state
, VARLINK_IDLE_CLIENT
) && (v
->write_disconnected
|| v
->got_pollhup
))
419 varlink_set_state(v
, VARLINK_PENDING_DISCONNECT
);
423 static int varlink_write(Varlink
*v
) {
428 if (!VARLINK_STATE_IS_ALIVE(v
->state
))
430 if (v
->connecting
) /* Writing while we are still wait for a non-blocking connect() to complete will
431 * result in ENOTCONN, hence exit early here */
433 if (v
->output_buffer_size
== 0)
435 if (v
->write_disconnected
)
440 /* We generally prefer recv()/send() (mostly because of MSG_NOSIGNAL) but also want to be compatible
441 * with non-socket IO, hence fall back automatically */
442 if (!v
->prefer_read_write
) {
443 n
= send(v
->fd
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
, MSG_DONTWAIT
|MSG_NOSIGNAL
);
444 if (n
< 0 && errno
== ENOTSOCK
)
445 v
->prefer_read_write
= true;
447 if (v
->prefer_read_write
)
448 n
= write(v
->fd
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
);
453 if (ERRNO_IS_DISCONNECT(errno
)) {
454 /* If we get informed about a disconnect on write, then let's remember that, but not
455 * act on it just yet. Let's wait for read() to report the issue first. */
456 v
->write_disconnected
= true;
463 v
->output_buffer_size
-= n
;
465 if (v
->output_buffer_size
== 0)
466 v
->output_buffer_index
= 0;
468 v
->output_buffer_index
+= n
;
470 v
->timestamp
= now(CLOCK_MONOTONIC
);
474 static int varlink_read(Varlink
*v
) {
480 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
))
482 if (v
->connecting
) /* read() on a socket while we are in connect() will fail with EINVAL, hence exit early here */
486 if (v
->input_buffer_unscanned
> 0)
488 if (v
->read_disconnected
)
491 if (v
->input_buffer_size
>= VARLINK_BUFFER_MAX
)
496 if (v
->input_buffer_allocated
<= v
->input_buffer_index
+ v
->input_buffer_size
) {
499 add
= MIN(VARLINK_BUFFER_MAX
- v
->input_buffer_size
, VARLINK_READ_SIZE
);
501 if (v
->input_buffer_index
== 0) {
503 if (!GREEDY_REALLOC(v
->input_buffer
, v
->input_buffer_allocated
, v
->input_buffer_size
+ add
))
509 b
= new(char, v
->input_buffer_size
+ add
);
513 memcpy(b
, v
->input_buffer
+ v
->input_buffer_index
, v
->input_buffer_size
);
515 free_and_replace(v
->input_buffer
, b
);
517 v
->input_buffer_allocated
= v
->input_buffer_size
+ add
;
518 v
->input_buffer_index
= 0;
522 rs
= v
->input_buffer_allocated
- (v
->input_buffer_index
+ v
->input_buffer_size
);
524 if (!v
->prefer_read_write
) {
525 n
= recv(v
->fd
, v
->input_buffer
+ v
->input_buffer_index
+ v
->input_buffer_size
, rs
, MSG_DONTWAIT
);
526 if (n
< 0 && errno
== ENOTSOCK
)
527 v
->prefer_read_write
= true;
529 if (v
->prefer_read_write
)
530 n
= read(v
->fd
, v
->input_buffer
+ v
->input_buffer_index
+ v
->input_buffer_size
, rs
);
535 if (ERRNO_IS_DISCONNECT(errno
)) {
536 v
->read_disconnected
= true;
542 if (n
== 0) { /* EOF */
543 v
->read_disconnected
= true;
547 v
->input_buffer_size
+= n
;
548 v
->input_buffer_unscanned
+= n
;
553 static int varlink_parse_message(Varlink
*v
) {
554 const char *e
, *begin
;
562 if (v
->input_buffer_unscanned
<= 0)
565 assert(v
->input_buffer_unscanned
<= v
->input_buffer_size
);
566 assert(v
->input_buffer_index
+ v
->input_buffer_size
<= v
->input_buffer_allocated
);
568 begin
= v
->input_buffer
+ v
->input_buffer_index
;
570 e
= memchr(begin
+ v
->input_buffer_size
- v
->input_buffer_unscanned
, 0, v
->input_buffer_unscanned
);
572 v
->input_buffer_unscanned
= 0;
578 varlink_log(v
, "New incoming message: %s", begin
);
580 r
= json_parse(begin
, &v
->current
, NULL
, NULL
);
584 v
->input_buffer_size
-= sz
;
586 if (v
->input_buffer_size
== 0)
587 v
->input_buffer_index
= 0;
589 v
->input_buffer_index
+= sz
;
591 v
->input_buffer_unscanned
= v
->input_buffer_size
;
595 static int varlink_test_timeout(Varlink
*v
) {
598 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
, VARLINK_CALLING
))
600 if (v
->timeout
== USEC_INFINITY
)
603 if (now(CLOCK_MONOTONIC
) < usec_add(v
->timestamp
, v
->timeout
))
606 varlink_set_state(v
, VARLINK_PENDING_TIMEOUT
);
611 static int varlink_dispatch_local_error(Varlink
*v
, const char *error
) {
617 if (!v
->reply_callback
)
620 r
= v
->reply_callback(v
, NULL
, error
, VARLINK_REPLY_ERROR
|VARLINK_REPLY_LOCAL
, v
->userdata
);
622 log_debug_errno(r
, "Reply callback returned error, ignoring: %m");
627 static int varlink_dispatch_timeout(Varlink
*v
) {
630 if (v
->state
!= VARLINK_PENDING_TIMEOUT
)
633 varlink_set_state(v
, VARLINK_PROCESSING_TIMEOUT
);
634 varlink_dispatch_local_error(v
, VARLINK_ERROR_TIMEOUT
);
640 static int varlink_dispatch_disconnect(Varlink
*v
) {
643 if (v
->state
!= VARLINK_PENDING_DISCONNECT
)
646 varlink_set_state(v
, VARLINK_PROCESSING_DISCONNECT
);
647 varlink_dispatch_local_error(v
, VARLINK_ERROR_DISCONNECTED
);
653 static int varlink_sanitize_parameters(JsonVariant
**v
) {
656 /* Varlink always wants a parameters list, hence make one if the caller doesn't want any */
658 return json_variant_new_object(v
, NULL
, 0);
659 else if (!json_variant_is_object(*v
))
665 static int varlink_dispatch_reply(Varlink
*v
) {
666 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
667 VarlinkReplyFlags flags
= 0;
668 const char *error
= NULL
;
675 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
, VARLINK_CALLING
))
680 assert(v
->n_pending
> 0);
682 if (!json_variant_is_object(v
->current
))
685 JSON_VARIANT_OBJECT_FOREACH(k
, e
, v
->current
) {
687 if (streq(k
, "error")) {
690 if (!json_variant_is_string(e
))
693 error
= json_variant_string(e
);
694 flags
|= VARLINK_REPLY_ERROR
;
696 } else if (streq(k
, "parameters")) {
699 if (!json_variant_is_object(e
))
702 parameters
= json_variant_ref(e
);
704 } else if (streq(k
, "continues")) {
705 if (FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
708 if (!json_variant_is_boolean(e
))
711 if (json_variant_boolean(e
))
712 flags
|= VARLINK_REPLY_CONTINUES
;
717 /* Replies with 'continue' set are only OK if we set 'more' when the method call was initiated */
718 if (v
->state
!= VARLINK_AWAITING_REPLY_MORE
&& FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
721 /* An error is final */
722 if (error
&& FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
725 r
= varlink_sanitize_parameters(¶meters
);
729 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
)) {
730 varlink_set_state(v
, VARLINK_PROCESSING_REPLY
);
732 if (v
->reply_callback
) {
733 r
= v
->reply_callback(v
, parameters
, error
, flags
, v
->userdata
);
735 log_debug_errno(r
, "Reply callback returned error, ignoring: %m");
738 v
->current
= json_variant_unref(v
->current
);
740 if (v
->state
== VARLINK_PROCESSING_REPLY
) {
742 assert(v
->n_pending
> 0);
744 if (!FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
748 FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
) ? VARLINK_AWAITING_REPLY_MORE
:
749 v
->n_pending
== 0 ? VARLINK_IDLE_CLIENT
: VARLINK_AWAITING_REPLY
);
752 assert(v
->state
== VARLINK_CALLING
);
753 varlink_set_state(v
, VARLINK_CALLED
);
759 varlink_set_state(v
, VARLINK_PROCESSING_FAILURE
);
760 varlink_dispatch_local_error(v
, VARLINK_ERROR_PROTOCOL
);
766 static int varlink_dispatch_method(Varlink
*v
) {
767 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
768 VarlinkMethodFlags flags
= 0;
769 const char *method
= NULL
, *error
;
771 VarlinkMethod callback
;
777 if (v
->state
!= VARLINK_IDLE_SERVER
)
782 if (!json_variant_is_object(v
->current
))
785 JSON_VARIANT_OBJECT_FOREACH(k
, e
, v
->current
) {
787 if (streq(k
, "method")) {
790 if (!json_variant_is_string(e
))
793 method
= json_variant_string(e
);
795 } else if (streq(k
, "parameters")) {
798 if (!json_variant_is_object(e
))
801 parameters
= json_variant_ref(e
);
803 } else if (streq(k
, "oneway")) {
805 if ((flags
& (VARLINK_METHOD_ONEWAY
|VARLINK_METHOD_MORE
)) != 0)
808 if (!json_variant_is_boolean(e
))
811 if (json_variant_boolean(e
))
812 flags
|= VARLINK_METHOD_ONEWAY
;
814 } else if (streq(k
, "more")) {
816 if ((flags
& (VARLINK_METHOD_ONEWAY
|VARLINK_METHOD_MORE
)) != 0)
819 if (!json_variant_is_boolean(e
))
822 if (json_variant_boolean(e
))
823 flags
|= VARLINK_METHOD_MORE
;
832 r
= varlink_sanitize_parameters(¶meters
);
836 varlink_set_state(v
, (flags
& VARLINK_METHOD_MORE
) ? VARLINK_PROCESSING_METHOD_MORE
:
837 (flags
& VARLINK_METHOD_ONEWAY
) ? VARLINK_PROCESSING_METHOD_ONEWAY
:
838 VARLINK_PROCESSING_METHOD
);
842 if (STR_IN_SET(method
, "org.varlink.service.GetInfo", "org.varlink.service.GetInterface")) {
843 /* For now, we don't implement a single of varlink's own methods */
845 error
= VARLINK_ERROR_METHOD_NOT_IMPLEMENTED
;
846 } else if (startswith(method
, "org.varlink.service.")) {
848 error
= VARLINK_ERROR_METHOD_NOT_FOUND
;
850 callback
= hashmap_get(v
->server
->methods
, method
);
851 error
= VARLINK_ERROR_METHOD_NOT_FOUND
;
855 r
= callback(v
, parameters
, flags
, v
->userdata
);
857 log_debug_errno(r
, "Callback for %s returned error: %m", method
);
859 /* We got an error back from the callback. Propagate it to the client if the method call remains unanswered. */
860 if (!FLAGS_SET(flags
, VARLINK_METHOD_ONEWAY
)) {
861 r
= varlink_errorb(v
, VARLINK_ERROR_SYSTEM
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("errno", JSON_BUILD_INTEGER(-r
))));
866 } else if (!FLAGS_SET(flags
, VARLINK_METHOD_ONEWAY
)) {
869 r
= varlink_errorb(v
, error
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
))));
876 case VARLINK_PROCESSED_METHOD
: /* Method call is fully processed */
877 case VARLINK_PROCESSING_METHOD_ONEWAY
: /* ditto */
878 v
->current
= json_variant_unref(v
->current
);
879 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
882 case VARLINK_PROCESSING_METHOD
: /* Method call wasn't replied to, will be replied to later */
883 varlink_set_state(v
, VARLINK_PENDING_METHOD
);
886 case VARLINK_PROCESSING_METHOD_MORE
: /* No reply for a "more" message was sent, more to come */
887 varlink_set_state(v
, VARLINK_PENDING_METHOD_MORE
);
891 assert_not_reached("Unexpected state");
901 varlink_set_state(v
, VARLINK_PROCESSING_FAILURE
);
902 varlink_dispatch_local_error(v
, VARLINK_ERROR_PROTOCOL
);
908 int varlink_process(Varlink
*v
) {
911 assert_return(v
, -EINVAL
);
913 if (v
->state
== VARLINK_DISCONNECTED
)
918 r
= varlink_write(v
);
922 r
= varlink_dispatch_reply(v
);
926 r
= varlink_dispatch_method(v
);
930 r
= varlink_parse_message(v
);
938 r
= varlink_test_disconnect(v
);
942 r
= varlink_dispatch_disconnect(v
);
946 r
= varlink_test_timeout(v
);
950 r
= varlink_dispatch_timeout(v
);
955 if (r
>= 0 && v
->defer_event_source
) {
958 /* If we did some processing, make sure we are called again soon */
959 q
= sd_event_source_set_enabled(v
->defer_event_source
, r
> 0 ? SD_EVENT_ON
: SD_EVENT_OFF
);
965 if (VARLINK_STATE_IS_ALIVE(v
->state
))
966 /* Initiate disconnection */
967 varlink_set_state(v
, VARLINK_PENDING_DISCONNECT
);
969 /* We failed while disconnecting, in that case close right away */
977 static void handle_revents(Varlink
*v
, int revents
) {
981 /* If we have seen POLLOUT or POLLHUP on a socket we are asynchronously waiting a connect()
982 * to complete on, we know we are ready. We don't read the connection error here though,
983 * we'll get the error on the next read() or write(). */
984 if ((revents
& (POLLOUT
|POLLHUP
)) == 0)
987 varlink_log(v
, "Anynchronous connection completed.");
988 v
->connecting
= false;
990 /* Note that we don't care much about POLLIN/POLLOUT here, we'll just try reading and writing
991 * what we can. However, we do care about POLLHUP to detect connection termination even if we
992 * momentarily don't want to read nor write anything. */
994 if (!FLAGS_SET(revents
, POLLHUP
))
997 varlink_log(v
, "Got POLLHUP from socket.");
998 v
->got_pollhup
= true;
1002 int varlink_wait(Varlink
*v
, usec_t timeout
) {
1008 assert_return(v
, -EINVAL
);
1010 if (v
->state
== VARLINK_DISCONNECTED
)
1013 r
= varlink_get_timeout(v
, &t
);
1016 if (t
!= USEC_INFINITY
) {
1019 n
= now(CLOCK_MONOTONIC
);
1023 t
= usec_sub_unsigned(t
, n
);
1026 if (timeout
!= USEC_INFINITY
&&
1027 (t
== USEC_INFINITY
|| timeout
< t
))
1030 fd
= varlink_get_fd(v
);
1034 events
= varlink_get_events(v
);
1038 pfd
= (struct pollfd
) {
1044 t
== USEC_INFINITY
? NULL
: timespec_store(&ts
, t
),
1049 handle_revents(v
, pfd
.revents
);
1051 return r
> 0 ? 1 : 0;
1054 int varlink_get_fd(Varlink
*v
) {
1056 assert_return(v
, -EINVAL
);
1058 if (v
->state
== VARLINK_DISCONNECTED
)
1066 int varlink_get_events(Varlink
*v
) {
1069 assert_return(v
, -EINVAL
);
1071 if (v
->state
== VARLINK_DISCONNECTED
)
1074 if (v
->connecting
) /* When processing an asynchronous connect(), we only wait for EPOLLOUT, which
1075 * tells us that the connection is now complete. Before that we should neither
1076 * write() or read() from the fd. */
1079 if (!v
->read_disconnected
&&
1080 IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
) &&
1082 v
->input_buffer_unscanned
<= 0)
1085 if (!v
->write_disconnected
&&
1086 v
->output_buffer_size
> 0)
1092 int varlink_get_timeout(Varlink
*v
, usec_t
*ret
) {
1093 assert_return(v
, -EINVAL
);
1095 if (v
->state
== VARLINK_DISCONNECTED
)
1098 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_AWAITING_REPLY_MORE
, VARLINK_CALLING
) &&
1099 v
->timeout
!= USEC_INFINITY
) {
1101 *ret
= usec_add(v
->timestamp
, v
->timeout
);
1105 *ret
= USEC_INFINITY
;
1110 int varlink_flush(Varlink
*v
) {
1113 assert_return(v
, -EINVAL
);
1115 if (v
->state
== VARLINK_DISCONNECTED
)
1121 if (v
->output_buffer_size
== 0)
1123 if (v
->write_disconnected
)
1126 r
= varlink_write(v
);
1134 pfd
= (struct pollfd
) {
1139 if (poll(&pfd
, 1, -1) < 0)
1142 handle_revents(v
, pfd
.revents
);
1148 static void varlink_detach_server(Varlink
*v
) {
1154 if (v
->server
->by_uid
&&
1155 v
->ucred_acquired
&&
1156 uid_is_valid(v
->ucred
.uid
)) {
1159 c
= PTR_TO_UINT(hashmap_get(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
)));
1163 (void) hashmap_remove(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
));
1165 (void) hashmap_replace(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
), UINT_TO_PTR(c
- 1));
1168 assert(v
->server
->n_connections
> 0);
1169 v
->server
->n_connections
--;
1171 /* If this is a connection associated to a server, then let's disconnect the server and the
1172 * connection from each other. This drops the dangling reference that connect_callback() set up. */
1173 v
->server
= varlink_server_unref(v
->server
);
1177 int varlink_close(Varlink
*v
) {
1179 assert_return(v
, -EINVAL
);
1181 if (v
->state
== VARLINK_DISCONNECTED
)
1184 varlink_set_state(v
, VARLINK_DISCONNECTED
);
1186 /* Let's take a reference first, since varlink_detach_server() might drop the final (dangling) ref
1187 * which would destroy us before we can call varlink_clear() */
1189 varlink_detach_server(v
);
1196 Varlink
* varlink_flush_close_unref(Varlink
*v
) {
1201 (void) varlink_flush(v
);
1202 (void) varlink_close(v
);
1204 return varlink_unref(v
);
1207 static int varlink_enqueue_json(Varlink
*v
, JsonVariant
*m
) {
1208 _cleanup_free_
char *text
= NULL
;
1214 r
= json_variant_format(m
, 0, &text
);
1217 assert(text
[r
] == '\0');
1219 if (v
->output_buffer_size
+ r
+ 1 > VARLINK_BUFFER_MAX
)
1222 varlink_log(v
, "Sending message: %s", text
);
1224 if (v
->output_buffer_size
== 0) {
1226 free_and_replace(v
->output_buffer
, text
);
1228 v
->output_buffer_size
= v
->output_buffer_allocated
= r
+ 1;
1229 v
->output_buffer_index
= 0;
1231 } else if (v
->output_buffer_index
== 0) {
1233 if (!GREEDY_REALLOC(v
->output_buffer
, v
->output_buffer_allocated
, v
->output_buffer_size
+ r
+ 1))
1236 memcpy(v
->output_buffer
+ v
->output_buffer_size
, text
, r
+ 1);
1237 v
->output_buffer_size
+= r
+ 1;
1241 const size_t new_size
= v
->output_buffer_size
+ r
+ 1;
1243 n
= new(char, new_size
);
1247 memcpy(mempcpy(n
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
), text
, r
+ 1);
1249 free_and_replace(v
->output_buffer
, n
);
1250 v
->output_buffer_allocated
= v
->output_buffer_size
= new_size
;
1251 v
->output_buffer_index
= 0;
1257 int varlink_send(Varlink
*v
, const char *method
, JsonVariant
*parameters
) {
1258 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1261 assert_return(v
, -EINVAL
);
1262 assert_return(method
, -EINVAL
);
1264 if (v
->state
== VARLINK_DISCONNECTED
)
1267 /* We allow enqueuing multiple method calls at once! */
1268 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
, VARLINK_AWAITING_REPLY
))
1271 r
= varlink_sanitize_parameters(¶meters
);
1275 r
= json_build(&m
, JSON_BUILD_OBJECT(
1276 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1277 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
)),
1278 JSON_BUILD_PAIR("oneway", JSON_BUILD_BOOLEAN(true))));
1282 r
= varlink_enqueue_json(v
, m
);
1286 /* No state change here, this is one-way only after all */
1287 v
->timestamp
= now(CLOCK_MONOTONIC
);
1291 int varlink_sendb(Varlink
*v
, const char *method
, ...) {
1292 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1296 assert_return(v
, -EINVAL
);
1298 va_start(ap
, method
);
1299 r
= json_buildv(¶meters
, ap
);
1305 return varlink_send(v
, method
, parameters
);
1308 int varlink_invoke(Varlink
*v
, const char *method
, JsonVariant
*parameters
) {
1309 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1312 assert_return(v
, -EINVAL
);
1313 assert_return(method
, -EINVAL
);
1315 if (v
->state
== VARLINK_DISCONNECTED
)
1318 /* We allow enqueing multiple method calls at once! */
1319 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
, VARLINK_AWAITING_REPLY
))
1322 r
= varlink_sanitize_parameters(¶meters
);
1326 r
= json_build(&m
, JSON_BUILD_OBJECT(
1327 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1328 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1332 r
= varlink_enqueue_json(v
, m
);
1336 varlink_set_state(v
, VARLINK_AWAITING_REPLY
);
1338 v
->timestamp
= now(CLOCK_MONOTONIC
);
1343 int varlink_invokeb(Varlink
*v
, const char *method
, ...) {
1344 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1348 assert_return(v
, -EINVAL
);
1350 va_start(ap
, method
);
1351 r
= json_buildv(¶meters
, ap
);
1357 return varlink_invoke(v
, method
, parameters
);
1360 int varlink_observe(Varlink
*v
, const char *method
, JsonVariant
*parameters
) {
1361 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1364 assert_return(v
, -EINVAL
);
1365 assert_return(method
, -EINVAL
);
1367 if (v
->state
== VARLINK_DISCONNECTED
)
1369 /* Note that we don't allow enqueuing multiple method calls when we are in more/continues mode! We
1370 * thus insist on an idle client here. */
1371 if (v
->state
!= VARLINK_IDLE_CLIENT
)
1374 r
= varlink_sanitize_parameters(¶meters
);
1378 r
= json_build(&m
, JSON_BUILD_OBJECT(
1379 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1380 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
)),
1381 JSON_BUILD_PAIR("more", JSON_BUILD_BOOLEAN(true))));
1385 r
= varlink_enqueue_json(v
, m
);
1390 varlink_set_state(v
, VARLINK_AWAITING_REPLY_MORE
);
1392 v
->timestamp
= now(CLOCK_MONOTONIC
);
1397 int varlink_observeb(Varlink
*v
, const char *method
, ...) {
1398 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1402 assert_return(v
, -EINVAL
);
1404 va_start(ap
, method
);
1405 r
= json_buildv(¶meters
, ap
);
1411 return varlink_observe(v
, method
, parameters
);
1417 JsonVariant
*parameters
,
1418 JsonVariant
**ret_parameters
,
1419 const char **ret_error_id
,
1420 VarlinkReplyFlags
*ret_flags
) {
1422 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1425 assert_return(v
, -EINVAL
);
1426 assert_return(method
, -EINVAL
);
1428 if (v
->state
== VARLINK_DISCONNECTED
)
1430 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
))
1433 assert(v
->n_pending
== 0); /* n_pending can't be > 0 if we are in VARLINK_IDLE_CLIENT state */
1435 r
= varlink_sanitize_parameters(¶meters
);
1439 r
= json_build(&m
, JSON_BUILD_OBJECT(
1440 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1441 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1445 r
= varlink_enqueue_json(v
, m
);
1449 varlink_set_state(v
, VARLINK_CALLING
);
1451 v
->timestamp
= now(CLOCK_MONOTONIC
);
1453 while (v
->state
== VARLINK_CALLING
) {
1455 r
= varlink_process(v
);
1461 r
= varlink_wait(v
, USEC_INFINITY
);
1468 case VARLINK_CALLED
:
1471 json_variant_unref(v
->reply
);
1472 v
->reply
= TAKE_PTR(v
->current
);
1474 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
1475 assert(v
->n_pending
== 1);
1479 *ret_parameters
= json_variant_by_key(v
->reply
, "parameters");
1481 *ret_error_id
= json_variant_string(json_variant_by_key(v
->reply
, "error"));
1487 case VARLINK_PENDING_DISCONNECT
:
1488 case VARLINK_DISCONNECTED
:
1491 case VARLINK_PENDING_TIMEOUT
:
1495 assert_not_reached("Unexpected state after method call.");
1502 JsonVariant
**ret_parameters
,
1503 const char **ret_error_id
,
1504 VarlinkReplyFlags
*ret_flags
, ...) {
1506 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1510 assert_return(v
, -EINVAL
);
1512 va_start(ap
, ret_flags
);
1513 r
= json_buildv(¶meters
, ap
);
1519 return varlink_call(v
, method
, parameters
, ret_parameters
, ret_error_id
, ret_flags
);
1522 int varlink_reply(Varlink
*v
, JsonVariant
*parameters
) {
1523 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1526 assert_return(v
, -EINVAL
);
1528 if (v
->state
== VARLINK_DISCONNECTED
)
1530 if (!IN_SET(v
->state
,
1531 VARLINK_PROCESSING_METHOD
, VARLINK_PROCESSING_METHOD_MORE
,
1532 VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
))
1535 r
= varlink_sanitize_parameters(¶meters
);
1539 r
= json_build(&m
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1543 r
= varlink_enqueue_json(v
, m
);
1547 if (IN_SET(v
->state
, VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
)) {
1548 /* We just replied to a method call that was let hanging for a while (i.e. we were outside of
1549 * the varlink_dispatch_method() stack frame), which means with this reply we are ready to
1550 * process further messages. */
1551 v
->current
= json_variant_unref(v
->current
);
1552 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
1554 /* We replied to a method call from within the varlink_dispatch_method() stack frame), which
1555 * means we should it handle the rest of the state engine. */
1556 varlink_set_state(v
, VARLINK_PROCESSED_METHOD
);
1561 int varlink_replyb(Varlink
*v
, ...) {
1562 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1566 assert_return(v
, -EINVAL
);
1569 r
= json_buildv(¶meters
, ap
);
1575 return varlink_reply(v
, parameters
);
1578 int varlink_error(Varlink
*v
, const char *error_id
, JsonVariant
*parameters
) {
1579 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1582 assert_return(v
, -EINVAL
);
1583 assert_return(error_id
, -EINVAL
);
1585 if (v
->state
== VARLINK_DISCONNECTED
)
1587 if (!IN_SET(v
->state
,
1588 VARLINK_PROCESSING_METHOD
, VARLINK_PROCESSING_METHOD_MORE
,
1589 VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
))
1592 r
= varlink_sanitize_parameters(¶meters
);
1596 r
= json_build(&m
, JSON_BUILD_OBJECT(
1597 JSON_BUILD_PAIR("error", JSON_BUILD_STRING(error_id
)),
1598 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1602 r
= varlink_enqueue_json(v
, m
);
1606 if (IN_SET(v
->state
, VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
)) {
1607 v
->current
= json_variant_unref(v
->current
);
1608 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
1610 varlink_set_state(v
, VARLINK_PROCESSED_METHOD
);
1615 int varlink_errorb(Varlink
*v
, const char *error_id
, ...) {
1616 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1620 assert_return(v
, -EINVAL
);
1621 assert_return(error_id
, -EINVAL
);
1623 va_start(ap
, error_id
);
1624 r
= json_buildv(¶meters
, ap
);
1630 return varlink_error(v
, error_id
, parameters
);
1633 int varlink_error_invalid_parameter(Varlink
*v
, JsonVariant
*parameters
) {
1635 assert_return(v
, -EINVAL
);
1636 assert_return(parameters
, -EINVAL
);
1638 /* We expect to be called in one of two ways: the 'parameters' argument is a string variant in which
1639 * case it is the parameter key name that is invalid. Or the 'parameters' argument is an object
1640 * variant in which case we'll pull out the first key. The latter mode is useful in functions that
1641 * don't expect any arguments. */
1643 if (json_variant_is_string(parameters
))
1644 return varlink_error(v
, VARLINK_ERROR_INVALID_PARAMETER
, parameters
);
1646 if (json_variant_is_object(parameters
) &&
1647 json_variant_elements(parameters
) > 0)
1648 return varlink_error(v
, VARLINK_ERROR_INVALID_PARAMETER
,
1649 json_variant_by_index(parameters
, 0));
1654 int varlink_notify(Varlink
*v
, JsonVariant
*parameters
) {
1655 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1658 assert_return(v
, -EINVAL
);
1660 if (v
->state
== VARLINK_DISCONNECTED
)
1662 if (!IN_SET(v
->state
, VARLINK_PROCESSING_METHOD_MORE
, VARLINK_PENDING_METHOD_MORE
))
1665 r
= varlink_sanitize_parameters(¶meters
);
1669 r
= json_build(&m
, JSON_BUILD_OBJECT(
1670 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
)),
1671 JSON_BUILD_PAIR("continues", JSON_BUILD_BOOLEAN(true))));
1675 r
= varlink_enqueue_json(v
, m
);
1679 /* No state change, as more is coming */
1683 int varlink_notifyb(Varlink
*v
, ...) {
1684 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1688 assert_return(v
, -EINVAL
);
1691 r
= json_buildv(¶meters
, ap
);
1697 return varlink_notify(v
, parameters
);
1700 int varlink_bind_reply(Varlink
*v
, VarlinkReply callback
) {
1701 assert_return(v
, -EINVAL
);
1703 if (callback
&& v
->reply_callback
&& callback
!= v
->reply_callback
)
1706 v
->reply_callback
= callback
;
1711 void* varlink_set_userdata(Varlink
*v
, void *userdata
) {
1714 assert_return(v
, NULL
);
1717 v
->userdata
= userdata
;
1722 void* varlink_get_userdata(Varlink
*v
) {
1723 assert_return(v
, NULL
);
1728 static int varlink_acquire_ucred(Varlink
*v
) {
1733 if (v
->ucred_acquired
)
1736 r
= getpeercred(v
->fd
, &v
->ucred
);
1740 v
->ucred_acquired
= true;
1744 int varlink_get_peer_uid(Varlink
*v
, uid_t
*ret
) {
1747 assert_return(v
, -EINVAL
);
1748 assert_return(ret
, -EINVAL
);
1750 r
= varlink_acquire_ucred(v
);
1754 if (!uid_is_valid(v
->ucred
.uid
))
1757 *ret
= v
->ucred
.uid
;
1761 int varlink_get_peer_pid(Varlink
*v
, pid_t
*ret
) {
1764 assert_return(v
, -EINVAL
);
1765 assert_return(ret
, -EINVAL
);
1767 r
= varlink_acquire_ucred(v
);
1771 if (!pid_is_valid(v
->ucred
.pid
))
1774 *ret
= v
->ucred
.pid
;
1778 int varlink_set_relative_timeout(Varlink
*v
, usec_t timeout
) {
1779 assert_return(v
, -EINVAL
);
1780 assert_return(timeout
> 0, -EINVAL
);
1782 v
->timeout
= timeout
;
1786 VarlinkServer
*varlink_get_server(Varlink
*v
) {
1787 assert_return(v
, NULL
);
1792 int varlink_set_description(Varlink
*v
, const char *description
) {
1793 assert_return(v
, -EINVAL
);
1795 return free_and_strdup(&v
->description
, description
);
1798 static int io_callback(sd_event_source
*s
, int fd
, uint32_t revents
, void *userdata
) {
1799 Varlink
*v
= userdata
;
1804 handle_revents(v
, revents
);
1805 (void) varlink_process(v
);
1810 static int time_callback(sd_event_source
*s
, uint64_t usec
, void *userdata
) {
1811 Varlink
*v
= userdata
;
1816 (void) varlink_process(v
);
1820 static int defer_callback(sd_event_source
*s
, void *userdata
) {
1821 Varlink
*v
= userdata
;
1826 (void) varlink_process(v
);
1830 static int prepare_callback(sd_event_source
*s
, void *userdata
) {
1831 Varlink
*v
= userdata
;
1839 e
= varlink_get_events(v
);
1843 r
= sd_event_source_set_io_events(v
->io_event_source
, e
);
1847 r
= varlink_get_timeout(v
, &until
);
1850 have_timeout
= r
> 0;
1853 r
= sd_event_source_set_time(v
->time_event_source
, until
);
1858 r
= sd_event_source_set_enabled(v
->time_event_source
, have_timeout
? SD_EVENT_ON
: SD_EVENT_OFF
);
1865 static int quit_callback(sd_event_source
*event
, void *userdata
) {
1866 Varlink
*v
= userdata
;
1877 int varlink_attach_event(Varlink
*v
, sd_event
*e
, int64_t priority
) {
1880 assert_return(v
, -EINVAL
);
1881 assert_return(!v
->event
, -EBUSY
);
1884 v
->event
= sd_event_ref(e
);
1886 r
= sd_event_default(&v
->event
);
1891 r
= sd_event_add_time(v
->event
, &v
->time_event_source
, CLOCK_MONOTONIC
, 0, 0, time_callback
, v
);
1895 r
= sd_event_source_set_priority(v
->time_event_source
, priority
);
1899 (void) sd_event_source_set_description(v
->time_event_source
, "varlink-time");
1901 r
= sd_event_add_exit(v
->event
, &v
->quit_event_source
, quit_callback
, v
);
1905 r
= sd_event_source_set_priority(v
->quit_event_source
, priority
);
1909 (void) sd_event_source_set_description(v
->quit_event_source
, "varlink-quit");
1911 r
= sd_event_add_io(v
->event
, &v
->io_event_source
, v
->fd
, 0, io_callback
, v
);
1915 r
= sd_event_source_set_prepare(v
->io_event_source
, prepare_callback
);
1919 r
= sd_event_source_set_priority(v
->io_event_source
, priority
);
1923 (void) sd_event_source_set_description(v
->io_event_source
, "varlink-io");
1925 r
= sd_event_add_defer(v
->event
, &v
->defer_event_source
, defer_callback
, v
);
1929 r
= sd_event_source_set_priority(v
->defer_event_source
, priority
);
1933 (void) sd_event_source_set_description(v
->defer_event_source
, "varlink-defer");
1938 varlink_detach_event(v
);
1942 void varlink_detach_event(Varlink
*v
) {
1946 varlink_detach_event_sources(v
);
1948 v
->event
= sd_event_unref(v
->event
);
1951 sd_event
*varlink_get_event(Varlink
*v
) {
1952 assert_return(v
, NULL
);
1957 int varlink_server_new(VarlinkServer
**ret
, VarlinkServerFlags flags
) {
1960 assert_return(ret
, -EINVAL
);
1961 assert_return((flags
& ~_VARLINK_SERVER_FLAGS_ALL
) == 0, -EINVAL
);
1963 s
= new(VarlinkServer
, 1);
1967 *s
= (VarlinkServer
) {
1970 .connections_max
= varlink_server_connections_max(NULL
),
1971 .connections_per_uid_max
= varlink_server_connections_per_uid_max(NULL
),
1978 static VarlinkServer
* varlink_server_destroy(VarlinkServer
*s
) {
1984 varlink_server_shutdown(s
);
1986 while ((m
= hashmap_steal_first_key(s
->methods
)))
1989 hashmap_free(s
->methods
);
1990 hashmap_free(s
->by_uid
);
1992 sd_event_unref(s
->event
);
1994 free(s
->description
);
1999 DEFINE_TRIVIAL_REF_UNREF_FUNC(VarlinkServer
, varlink_server
, varlink_server_destroy
);
2001 static int validate_connection(VarlinkServer
*server
, const struct ucred
*ucred
) {
2007 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ROOT_ONLY
))
2008 allowed
= ucred
->uid
== 0;
2010 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_MYSELF_ONLY
))
2011 allowed
= allowed
> 0 || ucred
->uid
== getuid();
2013 if (allowed
== 0) { /* Allow access when it is explicitly allowed or when neither
2014 * VARLINK_SERVER_ROOT_ONLY nor VARLINK_SERVER_MYSELF_ONLY are specified. */
2015 varlink_server_log(server
, "Unprivileged client attempted connection, refusing.");
2019 if (server
->n_connections
>= server
->connections_max
) {
2020 varlink_server_log(server
, "Connection limit of %u reached, refusing.", server
->connections_max
);
2024 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ACCOUNT_UID
)) {
2027 if (!uid_is_valid(ucred
->uid
)) {
2028 varlink_server_log(server
, "Client with invalid UID attempted connection, refusing.");
2032 c
= PTR_TO_UINT(hashmap_get(server
->by_uid
, UID_TO_PTR(ucred
->uid
)));
2033 if (c
>= server
->connections_per_uid_max
) {
2034 varlink_server_log(server
, "Per-UID connection limit of %u reached, refusing.",
2035 server
->connections_per_uid_max
);
2043 static int count_connection(VarlinkServer
*server
, struct ucred
*ucred
) {
2050 server
->n_connections
++;
2052 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ACCOUNT_UID
)) {
2053 r
= hashmap_ensure_allocated(&server
->by_uid
, NULL
);
2055 return log_debug_errno(r
, "Failed to allocate UID hash table: %m");
2057 c
= PTR_TO_UINT(hashmap_get(server
->by_uid
, UID_TO_PTR(ucred
->uid
)));
2059 varlink_server_log(server
, "Connections of user " UID_FMT
": %u (of %u max)",
2060 ucred
->uid
, c
, server
->connections_per_uid_max
);
2062 r
= hashmap_replace(server
->by_uid
, UID_TO_PTR(ucred
->uid
), UINT_TO_PTR(c
+ 1));
2064 return log_debug_errno(r
, "Failed to increment counter in UID hash table: %m");
2070 int varlink_server_add_connection(VarlinkServer
*server
, int fd
, Varlink
**ret
) {
2071 _cleanup_(varlink_unrefp
) Varlink
*v
= NULL
;
2072 bool ucred_acquired
;
2076 assert_return(server
, -EINVAL
);
2077 assert_return(fd
>= 0, -EBADF
);
2079 if ((server
->flags
& (VARLINK_SERVER_ROOT_ONLY
|VARLINK_SERVER_ACCOUNT_UID
)) != 0) {
2080 r
= getpeercred(fd
, &ucred
);
2082 return varlink_server_log_errno(server
, r
, "Failed to acquire peer credentials of incoming socket, refusing: %m");
2084 ucred_acquired
= true;
2086 r
= validate_connection(server
, &ucred
);
2092 ucred_acquired
= false;
2094 r
= varlink_new(&v
);
2096 return varlink_server_log_errno(server
, r
, "Failed to allocate connection object: %m");
2098 r
= count_connection(server
, &ucred
);
2103 v
->userdata
= server
->userdata
;
2104 if (ucred_acquired
) {
2106 v
->ucred_acquired
= true;
2109 (void) asprintf(&v
->description
, "%s-%i", server
->description
?: "varlink", v
->fd
);
2111 /* Link up the server and the connection, and take reference in both directions. Note that the
2112 * reference on the connection is left dangling. It will be dropped when the connection is closed,
2113 * which happens in varlink_close(), including in the event loop quit callback. */
2114 v
->server
= varlink_server_ref(server
);
2117 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
2119 if (server
->event
) {
2120 r
= varlink_attach_event(v
, server
->event
, server
->event_priority
);
2122 varlink_log_errno(v
, r
, "Failed to attach new connection: %m");
2123 v
->fd
= -1; /* take the fd out of the connection again */
2135 static int connect_callback(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
2136 VarlinkServerSocket
*ss
= userdata
;
2137 _cleanup_close_
int cfd
= -1;
2144 varlink_server_log(ss
->server
, "New incoming connection.");
2146 cfd
= accept4(fd
, NULL
, NULL
, SOCK_NONBLOCK
|SOCK_CLOEXEC
);
2148 if (ERRNO_IS_ACCEPT_AGAIN(errno
))
2151 return varlink_server_log_errno(ss
->server
, errno
, "Failed to accept incoming socket: %m");
2154 r
= varlink_server_add_connection(ss
->server
, cfd
, &v
);
2160 if (ss
->server
->connect_callback
) {
2161 r
= ss
->server
->connect_callback(ss
->server
, v
, ss
->server
->userdata
);
2163 varlink_log_errno(v
, r
, "Connection callback returned error, disconnecting client: %m");
2172 int varlink_server_listen_fd(VarlinkServer
*s
, int fd
) {
2173 _cleanup_free_ VarlinkServerSocket
*ss
= NULL
;
2176 assert_return(s
, -EINVAL
);
2177 assert_return(fd
>= 0, -EBADF
);
2179 r
= fd_nonblock(fd
, true);
2183 ss
= new(VarlinkServerSocket
, 1);
2187 *ss
= (VarlinkServerSocket
) {
2193 _cleanup_(sd_event_source_unrefp
) sd_event_source
*es
= NULL
;
2195 r
= sd_event_add_io(s
->event
, &es
, fd
, EPOLLIN
, connect_callback
, ss
);
2199 r
= sd_event_source_set_priority(ss
->event_source
, s
->event_priority
);
2204 LIST_PREPEND(sockets
, s
->sockets
, TAKE_PTR(ss
));
2208 int varlink_server_listen_address(VarlinkServer
*s
, const char *address
, mode_t m
) {
2209 union sockaddr_union sockaddr
;
2210 _cleanup_close_
int fd
= -1;
2213 assert_return(s
, -EINVAL
);
2214 assert_return(address
, -EINVAL
);
2215 assert_return((m
& ~0777) == 0, -EINVAL
);
2217 r
= sockaddr_un_set_path(&sockaddr
.un
, address
);
2221 fd
= socket(AF_UNIX
, SOCK_STREAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
2225 fd
= fd_move_above_stdio(fd
);
2227 (void) sockaddr_un_unlink(&sockaddr
.un
);
2229 RUN_WITH_UMASK(~m
& 0777)
2230 if (bind(fd
, &sockaddr
.sa
, SOCKADDR_UN_LEN(sockaddr
.un
)) < 0)
2233 if (listen(fd
, SOMAXCONN
) < 0)
2236 r
= varlink_server_listen_fd(s
, fd
);
2244 void* varlink_server_set_userdata(VarlinkServer
*s
, void *userdata
) {
2247 assert_return(s
, NULL
);
2250 s
->userdata
= userdata
;
2255 void* varlink_server_get_userdata(VarlinkServer
*s
) {
2256 assert_return(s
, NULL
);
2261 static VarlinkServerSocket
* varlink_server_socket_destroy(VarlinkServerSocket
*ss
) {
2266 LIST_REMOVE(sockets
, ss
->server
->sockets
, ss
);
2268 sd_event_source_disable_unref(ss
->event_source
);
2276 int varlink_server_shutdown(VarlinkServer
*s
) {
2277 assert_return(s
, -EINVAL
);
2280 varlink_server_socket_destroy(s
->sockets
);
2285 int varlink_server_attach_event(VarlinkServer
*s
, sd_event
*e
, int64_t priority
) {
2286 VarlinkServerSocket
*ss
;
2289 assert_return(s
, -EINVAL
);
2290 assert_return(!s
->event
, -EBUSY
);
2293 s
->event
= sd_event_ref(e
);
2295 r
= sd_event_default(&s
->event
);
2300 LIST_FOREACH(sockets
, ss
, s
->sockets
) {
2301 assert(!ss
->event_source
);
2303 r
= sd_event_add_io(s
->event
, &ss
->event_source
, ss
->fd
, EPOLLIN
, connect_callback
, ss
);
2307 r
= sd_event_source_set_priority(ss
->event_source
, priority
);
2312 s
->event_priority
= priority
;
2316 varlink_server_detach_event(s
);
2320 int varlink_server_detach_event(VarlinkServer
*s
) {
2321 VarlinkServerSocket
*ss
;
2323 assert_return(s
, -EINVAL
);
2325 LIST_FOREACH(sockets
, ss
, s
->sockets
) {
2327 if (!ss
->event_source
)
2330 (void) sd_event_source_set_enabled(ss
->event_source
, SD_EVENT_OFF
);
2331 ss
->event_source
= sd_event_source_unref(ss
->event_source
);
2334 sd_event_unref(s
->event
);
2338 sd_event
*varlink_server_get_event(VarlinkServer
*s
) {
2339 assert_return(s
, NULL
);
2344 int varlink_server_bind_method(VarlinkServer
*s
, const char *method
, VarlinkMethod callback
) {
2348 assert_return(s
, -EINVAL
);
2349 assert_return(method
, -EINVAL
);
2350 assert_return(callback
, -EINVAL
);
2352 if (startswith(method
, "org.varlink.service."))
2355 r
= hashmap_ensure_allocated(&s
->methods
, &string_hash_ops
);
2363 r
= hashmap_put(s
->methods
, m
, callback
);
2372 int varlink_server_bind_method_many_internal(VarlinkServer
*s
, ...) {
2376 assert_return(s
, -EINVAL
);
2380 VarlinkMethod callback
;
2383 method
= va_arg(ap
, const char *);
2387 callback
= va_arg(ap
, VarlinkMethod
);
2389 r
= varlink_server_bind_method(s
, method
, callback
);
2398 int varlink_server_bind_connect(VarlinkServer
*s
, VarlinkConnect callback
) {
2399 assert_return(s
, -EINVAL
);
2401 if (callback
&& s
->connect_callback
&& callback
!= s
->connect_callback
)
2404 s
->connect_callback
= callback
;
2408 unsigned varlink_server_connections_max(VarlinkServer
*s
) {
2411 /* If a server is specified, return the setting for that server, otherwise the default value */
2413 return s
->connections_max
;
2415 dts
= getdtablesize();
2418 /* Make sure we never use up more than ¾th of RLIMIT_NOFILE for IPC */
2419 if (VARLINK_DEFAULT_CONNECTIONS_MAX
> (unsigned) dts
/ 4 * 3)
2422 return VARLINK_DEFAULT_CONNECTIONS_MAX
;
2425 unsigned varlink_server_connections_per_uid_max(VarlinkServer
*s
) {
2429 return s
->connections_per_uid_max
;
2431 /* Make sure to never use up more than ¾th of available connections for a single user */
2432 m
= varlink_server_connections_max(NULL
);
2433 if (VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX
> m
)
2436 return VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX
;
2439 int varlink_server_set_connections_per_uid_max(VarlinkServer
*s
, unsigned m
) {
2440 assert_return(s
, -EINVAL
);
2441 assert_return(m
> 0, -EINVAL
);
2443 s
->connections_per_uid_max
= m
;
2447 int varlink_server_set_connections_max(VarlinkServer
*s
, unsigned m
) {
2448 assert_return(s
, -EINVAL
);
2449 assert_return(m
> 0, -EINVAL
);
2451 s
->connections_max
= m
;
2455 int varlink_server_set_description(VarlinkServer
*s
, const char *description
) {
2456 assert_return(s
, -EINVAL
);
2458 return free_and_strdup(&s
->description
, description
);