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
,
34 VARLINK_PROCESSING_REPLY
,
36 /* Server side states */
38 VARLINK_PROCESSING_METHOD
,
39 VARLINK_PROCESSING_METHOD_MORE
,
40 VARLINK_PROCESSING_METHOD_ONEWAY
,
41 VARLINK_PROCESSED_METHOD
,
42 VARLINK_PROCESSED_METHOD_MORE
,
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, \
68 VARLINK_PROCESSING_REPLY, \
69 VARLINK_IDLE_SERVER, \
70 VARLINK_PROCESSING_METHOD, \
71 VARLINK_PROCESSING_METHOD_MORE, \
72 VARLINK_PROCESSING_METHOD_ONEWAY, \
73 VARLINK_PROCESSED_METHOD, \
74 VARLINK_PROCESSED_METHOD_MORE, \
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_CALLING
] = "calling",
189 [VARLINK_CALLED
] = "called",
190 [VARLINK_PROCESSING_REPLY
] = "processing-reply",
191 [VARLINK_IDLE_SERVER
] = "idle-server",
192 [VARLINK_PROCESSING_METHOD
] = "processing-method",
193 [VARLINK_PROCESSING_METHOD_MORE
] = "processing-method-more",
194 [VARLINK_PROCESSING_METHOD_ONEWAY
] = "processing-method-oneway",
195 [VARLINK_PROCESSED_METHOD
] = "processed-method",
196 [VARLINK_PROCESSED_METHOD_MORE
] = "processed-method-more",
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
) {
232 varlink_log(v
, "varlink: changing state %s → %s",
233 varlink_state_to_string(v
->state
),
234 varlink_state_to_string(state
));
239 static int varlink_new(Varlink
**ret
) {
252 .state
= _VARLINK_STATE_INVALID
,
254 .ucred
.uid
= UID_INVALID
,
255 .ucred
.gid
= GID_INVALID
,
257 .timestamp
= USEC_INFINITY
,
258 .timeout
= VARLINK_DEFAULT_TIMEOUT_USEC
265 int varlink_connect_address(Varlink
**ret
, const char *address
) {
266 _cleanup_(varlink_unrefp
) Varlink
*v
= NULL
;
267 union sockaddr_union sockaddr
;
270 assert_return(ret
, -EINVAL
);
271 assert_return(address
, -EINVAL
);
273 r
= sockaddr_un_set_path(&sockaddr
.un
, address
);
281 v
->fd
= socket(AF_UNIX
, SOCK_STREAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
285 if (connect(v
->fd
, &sockaddr
.sa
, SOCKADDR_UN_LEN(sockaddr
.un
)) < 0) {
286 if (!IN_SET(errno
, EAGAIN
, EINPROGRESS
))
289 v
->connecting
= true; /* We are asynchronously connecting, i.e. the connect() is being
290 * processed in the background. As long as that's the case the socket
291 * is in a special state: it's there, we can poll it for EPOLLOUT, but
292 * if we attempt to write() to it before we see EPOLLOUT we'll get
293 * ENOTCONN (and not EAGAIN, like we would for a normal connected
294 * socket that isn't writable at the moment). Since ENOTCONN on write()
295 * hence can mean two different things (i.e. connection not complete
296 * yet vs. already disconnected again), we store as a boolean whether
297 * we are still in connect(). */
300 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
306 int varlink_connect_fd(Varlink
**ret
, int fd
) {
310 assert_return(ret
, -EINVAL
);
311 assert_return(fd
>= 0, -EBADF
);
313 r
= fd_nonblock(fd
, true);
322 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
324 /* Note that if this function is called we assume the passed socket (if it is one) is already
325 * properly connected, i.e. any asynchronous connect() done on it already completed. Because of that
326 * we'll not set the 'connecting' boolean here, i.e. we don't need to avoid write()ing to the socket
327 * until the connection is fully set up. Behaviour here is hence a bit different from
328 * varlink_connect_address() above, as there we do handle asynchronous connections ourselves and
329 * avoid doing write() on it before we saw EPOLLOUT for the first time. */
335 static void varlink_detach_event_sources(Varlink
*v
) {
338 if (v
->io_event_source
) {
339 (void) sd_event_source_set_enabled(v
->io_event_source
, SD_EVENT_OFF
);
340 v
->io_event_source
= sd_event_source_unref(v
->io_event_source
);
343 if (v
->time_event_source
) {
344 (void) sd_event_source_set_enabled(v
->time_event_source
, SD_EVENT_OFF
);
345 v
->time_event_source
= sd_event_source_unref(v
->time_event_source
);
348 if (v
->quit_event_source
) {
349 (void) sd_event_source_set_enabled(v
->quit_event_source
, SD_EVENT_OFF
);
350 v
->quit_event_source
= sd_event_source_unref(v
->quit_event_source
);
353 if (v
->defer_event_source
) {
354 (void) sd_event_source_set_enabled(v
->defer_event_source
, SD_EVENT_OFF
);
355 v
->defer_event_source
= sd_event_source_unref(v
->defer_event_source
);
359 static void varlink_clear(Varlink
*v
) {
362 varlink_detach_event_sources(v
);
364 v
->fd
= safe_close(v
->fd
);
366 v
->input_buffer
= mfree(v
->input_buffer
);
367 v
->output_buffer
= mfree(v
->output_buffer
);
369 v
->current
= json_variant_unref(v
->current
);
370 v
->reply
= json_variant_unref(v
->reply
);
372 v
->event
= sd_event_unref(v
->event
);
375 static Varlink
* varlink_destroy(Varlink
*v
) {
379 /* If this is called the server object must already been unreffed here. Why that? because when we
380 * linked up the varlink connection with the server object we took one ref in each direction */
385 free(v
->description
);
389 DEFINE_TRIVIAL_REF_UNREF_FUNC(Varlink
, varlink
, varlink_destroy
);
391 static int varlink_test_disconnect(Varlink
*v
) {
394 /* Tests whether we the the connection has been terminated. We are careful to not stop processing it
395 * prematurely, since we want to handle half-open connections as well as possible and want to flush
396 * out and read data before we close down if we can. */
398 /* Already disconnected? */
399 if (!VARLINK_STATE_IS_ALIVE(v
->state
))
402 /* Wait until connection setup is complete, i.e. until asynchronous connect() completes */
406 /* Still something to write and we can write? Stay around */
407 if (v
->output_buffer_size
> 0 && !v
->write_disconnected
)
410 /* Both sides gone already? Then there's no need to stick around */
411 if (v
->read_disconnected
&& v
->write_disconnected
)
414 /* If we are waiting for incoming data but the read side is shut down, disconnect. */
415 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
) && v
->read_disconnected
)
418 /* Similar, if are a client that hasn't written anything yet but the write side is dead, also
419 * disconnect. We also explicitly check for POLLHUP here since we likely won't notice the write side
420 * being down if we never wrote anything. */
421 if (IN_SET(v
->state
, VARLINK_IDLE_CLIENT
) && (v
->write_disconnected
|| v
->got_pollhup
))
427 varlink_set_state(v
, VARLINK_PENDING_DISCONNECT
);
431 static int varlink_write(Varlink
*v
) {
436 if (!VARLINK_STATE_IS_ALIVE(v
->state
))
438 if (v
->connecting
) /* Writing while we are still wait for a non-blocking connect() to complete will
439 * result in ENOTCONN, hence exit early here */
441 if (v
->output_buffer_size
== 0)
443 if (v
->write_disconnected
)
448 /* We generally prefer recv()/send() (mostly because of MSG_NOSIGNAL) but also want to be compatible
449 * with non-socket IO, hence fall back automatically */
450 if (!v
->prefer_read_write
) {
451 n
= send(v
->fd
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
, MSG_DONTWAIT
|MSG_NOSIGNAL
);
452 if (n
< 0 && errno
== ENOTSOCK
)
453 v
->prefer_read_write
= true;
455 if (v
->prefer_read_write
)
456 n
= write(v
->fd
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
);
461 if (ERRNO_IS_DISCONNECT(errno
)) {
462 /* If we get informed about a disconnect on write, then let's remember that, but not
463 * act on it just yet. Let's wait for read() to report the issue first. */
464 v
->write_disconnected
= true;
471 v
->output_buffer_size
-= n
;
473 if (v
->output_buffer_size
== 0)
474 v
->output_buffer_index
= 0;
476 v
->output_buffer_index
+= n
;
478 v
->timestamp
= now(CLOCK_MONOTONIC
);
482 static int varlink_read(Varlink
*v
) {
488 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
))
490 if (v
->connecting
) /* read() on a socket while we are in connect() will fail with EINVAL, hence exit early here */
494 if (v
->input_buffer_unscanned
> 0)
496 if (v
->read_disconnected
)
499 if (v
->input_buffer_size
>= VARLINK_BUFFER_MAX
)
504 if (v
->input_buffer_allocated
<= v
->input_buffer_index
+ v
->input_buffer_size
) {
507 add
= MIN(VARLINK_BUFFER_MAX
- v
->input_buffer_size
, VARLINK_READ_SIZE
);
509 if (v
->input_buffer_index
== 0) {
511 if (!GREEDY_REALLOC(v
->input_buffer
, v
->input_buffer_allocated
, v
->input_buffer_size
+ add
))
517 b
= new(char, v
->input_buffer_size
+ add
);
521 memcpy(b
, v
->input_buffer
+ v
->input_buffer_index
, v
->input_buffer_size
);
523 free_and_replace(v
->input_buffer
, b
);
525 v
->input_buffer_allocated
= v
->input_buffer_size
+ add
;
526 v
->input_buffer_index
= 0;
530 rs
= v
->input_buffer_allocated
- (v
->input_buffer_index
+ v
->input_buffer_size
);
532 if (!v
->prefer_read_write
) {
533 n
= recv(v
->fd
, v
->input_buffer
+ v
->input_buffer_index
+ v
->input_buffer_size
, rs
, MSG_DONTWAIT
);
534 if (n
< 0 && errno
== ENOTSOCK
)
535 v
->prefer_read_write
= true;
537 if (v
->prefer_read_write
)
538 n
= read(v
->fd
, v
->input_buffer
+ v
->input_buffer_index
+ v
->input_buffer_size
, rs
);
543 if (ERRNO_IS_DISCONNECT(errno
)) {
544 v
->read_disconnected
= true;
550 if (n
== 0) { /* EOF */
551 v
->read_disconnected
= true;
555 v
->input_buffer_size
+= n
;
556 v
->input_buffer_unscanned
+= n
;
561 static int varlink_parse_message(Varlink
*v
) {
562 const char *e
, *begin
;
570 if (v
->input_buffer_unscanned
<= 0)
573 assert(v
->input_buffer_unscanned
<= v
->input_buffer_size
);
574 assert(v
->input_buffer_index
+ v
->input_buffer_size
<= v
->input_buffer_allocated
);
576 begin
= v
->input_buffer
+ v
->input_buffer_index
;
578 e
= memchr(begin
+ v
->input_buffer_size
- v
->input_buffer_unscanned
, 0, v
->input_buffer_unscanned
);
580 v
->input_buffer_unscanned
= 0;
586 varlink_log(v
, "New incoming message: %s", begin
);
588 r
= json_parse(begin
, &v
->current
, NULL
, NULL
);
592 v
->input_buffer_size
-= sz
;
594 if (v
->input_buffer_size
== 0)
595 v
->input_buffer_index
= 0;
597 v
->input_buffer_index
+= sz
;
599 v
->input_buffer_unscanned
= v
->input_buffer_size
;
603 static int varlink_test_timeout(Varlink
*v
) {
606 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
))
608 if (v
->timeout
== USEC_INFINITY
)
611 if (now(CLOCK_MONOTONIC
) < usec_add(v
->timestamp
, v
->timeout
))
614 varlink_set_state(v
, VARLINK_PENDING_TIMEOUT
);
619 static int varlink_dispatch_local_error(Varlink
*v
, const char *error
) {
625 if (!v
->reply_callback
)
628 r
= v
->reply_callback(v
, NULL
, error
, VARLINK_REPLY_ERROR
|VARLINK_REPLY_LOCAL
, v
->userdata
);
630 log_debug_errno(r
, "Reply callback returned error, ignoring: %m");
635 static int varlink_dispatch_timeout(Varlink
*v
) {
638 if (v
->state
!= VARLINK_PENDING_TIMEOUT
)
641 varlink_set_state(v
, VARLINK_PROCESSING_TIMEOUT
);
642 varlink_dispatch_local_error(v
, VARLINK_ERROR_TIMEOUT
);
648 static int varlink_dispatch_disconnect(Varlink
*v
) {
651 if (v
->state
!= VARLINK_PENDING_DISCONNECT
)
654 varlink_set_state(v
, VARLINK_PROCESSING_DISCONNECT
);
655 varlink_dispatch_local_error(v
, VARLINK_ERROR_DISCONNECTED
);
661 static int varlink_sanitize_parameters(JsonVariant
**v
) {
664 /* Varlink always wants a parameters list, hence make one if the caller doesn't want any */
666 return json_variant_new_object(v
, NULL
, 0);
667 else if (!json_variant_is_object(*v
))
673 static int varlink_dispatch_reply(Varlink
*v
) {
674 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
675 VarlinkReplyFlags flags
= 0;
676 const char *error
= NULL
;
683 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
))
688 assert(v
->n_pending
> 0);
690 if (!json_variant_is_object(v
->current
))
693 JSON_VARIANT_OBJECT_FOREACH(k
, e
, v
->current
) {
695 if (streq(k
, "error")) {
698 if (!json_variant_is_string(e
))
701 error
= json_variant_string(e
);
702 flags
|= VARLINK_REPLY_ERROR
;
704 } else if (streq(k
, "parameters")) {
707 if (!json_variant_is_object(e
))
710 parameters
= json_variant_ref(e
);
712 } else if (streq(k
, "continues")) {
713 if (FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
716 if (!json_variant_is_boolean(e
))
719 if (json_variant_boolean(e
))
720 flags
|= VARLINK_REPLY_CONTINUES
;
725 if (error
&& FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
728 r
= varlink_sanitize_parameters(¶meters
);
732 if (v
->state
== VARLINK_AWAITING_REPLY
) {
733 varlink_set_state(v
, VARLINK_PROCESSING_REPLY
);
735 if (v
->reply_callback
) {
736 r
= v
->reply_callback(v
, parameters
, error
, flags
, v
->userdata
);
738 log_debug_errno(r
, "Reply callback returned error, ignoring: %m");
741 v
->current
= json_variant_unref(v
->current
);
743 if (v
->state
== VARLINK_PROCESSING_REPLY
) {
744 assert(v
->n_pending
> 0);
747 varlink_set_state(v
, v
->n_pending
== 0 ? VARLINK_IDLE_CLIENT
: VARLINK_AWAITING_REPLY
);
750 assert(v
->state
== VARLINK_CALLING
);
752 if (FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
755 varlink_set_state(v
, VARLINK_CALLED
);
761 varlink_set_state(v
, VARLINK_PROCESSING_FAILURE
);
762 varlink_dispatch_local_error(v
, VARLINK_ERROR_PROTOCOL
);
768 static int varlink_dispatch_method(Varlink
*v
) {
769 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
770 VarlinkMethodFlags flags
= 0;
771 const char *method
= NULL
, *error
;
773 VarlinkMethod callback
;
779 if (v
->state
!= VARLINK_IDLE_SERVER
)
784 if (!json_variant_is_object(v
->current
))
787 JSON_VARIANT_OBJECT_FOREACH(k
, e
, v
->current
) {
789 if (streq(k
, "method")) {
792 if (!json_variant_is_string(e
))
795 method
= json_variant_string(e
);
797 } else if (streq(k
, "parameters")) {
800 if (!json_variant_is_object(e
))
803 parameters
= json_variant_ref(e
);
805 } else if (streq(k
, "oneway")) {
807 if ((flags
& (VARLINK_METHOD_ONEWAY
|VARLINK_METHOD_MORE
)) != 0)
810 if (!json_variant_is_boolean(e
))
813 if (json_variant_boolean(e
))
814 flags
|= VARLINK_METHOD_ONEWAY
;
816 } else if (streq(k
, "more")) {
818 if ((flags
& (VARLINK_METHOD_ONEWAY
|VARLINK_METHOD_MORE
)) != 0)
821 if (!json_variant_is_boolean(e
))
824 if (json_variant_boolean(e
))
825 flags
|= VARLINK_METHOD_MORE
;
834 r
= varlink_sanitize_parameters(¶meters
);
838 varlink_set_state(v
, (flags
& VARLINK_METHOD_MORE
) ? VARLINK_PROCESSING_METHOD_MORE
:
839 (flags
& VARLINK_METHOD_ONEWAY
) ? VARLINK_PROCESSING_METHOD_ONEWAY
:
840 VARLINK_PROCESSING_METHOD
);
844 if (STR_IN_SET(method
, "org.varlink.service.GetInfo", "org.varlink.service.GetInterface")) {
845 /* For now, we don't implement a single of varlink's own methods */
847 error
= VARLINK_ERROR_METHOD_NOT_IMPLEMENTED
;
848 } else if (startswith(method
, "org.varlink.service.")) {
850 error
= VARLINK_ERROR_METHOD_NOT_FOUND
;
852 callback
= hashmap_get(v
->server
->methods
, method
);
853 error
= VARLINK_ERROR_METHOD_NOT_FOUND
;
857 r
= callback(v
, parameters
, flags
, v
->userdata
);
859 log_debug_errno(r
, "Callback for %s returned error: %m", method
);
861 /* We got an error back from the callback. Propagate it to the client if the method call remains unanswered. */
862 if (!FLAGS_SET(flags
, VARLINK_METHOD_ONEWAY
)) {
863 r
= varlink_errorb(v
, VARLINK_ERROR_SYSTEM
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("errno", JSON_BUILD_INTEGER(-r
))));
868 } else if (!FLAGS_SET(flags
, VARLINK_METHOD_ONEWAY
)) {
871 r
= varlink_errorb(v
, error
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
))));
878 case VARLINK_PROCESSED_METHOD
: /* Method call is fully processed */
879 case VARLINK_PROCESSING_METHOD_ONEWAY
: /* ditto */
880 v
->current
= json_variant_unref(v
->current
);
881 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
884 case VARLINK_PROCESSING_METHOD
: /* Method call wasn't replied to, will be replied to later */
885 varlink_set_state(v
, VARLINK_PENDING_METHOD
);
888 case VARLINK_PROCESSED_METHOD_MORE
: /* One reply for a "more" message was sent, more to come */
889 case VARLINK_PROCESSING_METHOD_MORE
: /* No reply for a "more" message was sent, more to come */
890 varlink_set_state(v
, VARLINK_PENDING_METHOD_MORE
);
894 assert_not_reached("Unexpected state");
904 varlink_set_state(v
, VARLINK_PROCESSING_FAILURE
);
905 varlink_dispatch_local_error(v
, VARLINK_ERROR_PROTOCOL
);
911 int varlink_process(Varlink
*v
) {
914 assert_return(v
, -EINVAL
);
916 if (v
->state
== VARLINK_DISCONNECTED
)
921 r
= varlink_write(v
);
925 r
= varlink_dispatch_reply(v
);
929 r
= varlink_dispatch_method(v
);
933 r
= varlink_parse_message(v
);
941 r
= varlink_test_disconnect(v
);
945 r
= varlink_dispatch_disconnect(v
);
949 r
= varlink_test_timeout(v
);
953 r
= varlink_dispatch_timeout(v
);
958 if (r
>= 0 && v
->defer_event_source
) {
961 /* If we did some processing, make sure we are called again soon */
962 q
= sd_event_source_set_enabled(v
->defer_event_source
, r
> 0 ? SD_EVENT_ON
: SD_EVENT_OFF
);
968 if (VARLINK_STATE_IS_ALIVE(v
->state
))
969 /* Initiate disconnection */
970 varlink_set_state(v
, VARLINK_PENDING_DISCONNECT
);
972 /* We failed while disconnecting, in that case close right away */
980 static void handle_revents(Varlink
*v
, int revents
) {
984 /* If we have seen POLLOUT or POLLHUP on a socket we are asynchronously waiting a connect()
985 * to complete on, we know we are ready. We don't read the connection error here though,
986 * we'll get the error on the next read() or write(). */
987 if ((revents
& (POLLOUT
|POLLHUP
)) == 0)
990 varlink_log(v
, "Anynchronous connection completed.");
991 v
->connecting
= false;
993 /* Note that we don't care much about POLLIN/POLLOUT here, we'll just try reading and writing
994 * what we can. However, we do care about POLLHUP to detect connection termination even if we
995 * momentarily don't want to read nor write anything. */
997 if (!FLAGS_SET(revents
, POLLHUP
))
1000 varlink_log(v
, "Got POLLHUP from socket.");
1001 v
->got_pollhup
= true;
1005 int varlink_wait(Varlink
*v
, usec_t timeout
) {
1011 assert_return(v
, -EINVAL
);
1012 assert_return(!v
->server
, -ENOTTY
);
1014 if (v
->state
== VARLINK_DISCONNECTED
)
1017 r
= varlink_get_timeout(v
, &t
);
1020 if (t
!= USEC_INFINITY
) {
1023 n
= now(CLOCK_MONOTONIC
);
1027 t
= usec_sub_unsigned(t
, n
);
1030 if (timeout
!= USEC_INFINITY
&&
1031 (t
== USEC_INFINITY
|| timeout
< t
))
1034 fd
= varlink_get_fd(v
);
1038 events
= varlink_get_events(v
);
1042 pfd
= (struct pollfd
) {
1048 t
== USEC_INFINITY
? NULL
: timespec_store(&ts
, t
),
1053 handle_revents(v
, pfd
.revents
);
1055 return r
> 0 ? 1 : 0;
1058 int varlink_get_fd(Varlink
*v
) {
1060 assert_return(v
, -EINVAL
);
1062 if (v
->state
== VARLINK_DISCONNECTED
)
1070 int varlink_get_events(Varlink
*v
) {
1073 assert_return(v
, -EINVAL
);
1075 if (v
->state
== VARLINK_DISCONNECTED
)
1078 if (v
->connecting
) /* When processing an asynchronous connect(), we only wait for EPOLLOUT, which
1079 * tells us that the connection is now complete. Before that we should neither
1080 * write() or read() from the fd. */
1083 if (!v
->read_disconnected
&&
1084 IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
) &&
1086 v
->input_buffer_unscanned
<= 0)
1089 if (!v
->write_disconnected
&&
1090 v
->output_buffer_size
> 0)
1096 int varlink_get_timeout(Varlink
*v
, usec_t
*ret
) {
1097 assert_return(v
, -EINVAL
);
1099 if (v
->state
== VARLINK_DISCONNECTED
)
1102 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
) &&
1103 v
->timeout
!= USEC_INFINITY
) {
1105 *ret
= usec_add(v
->timestamp
, v
->timeout
);
1109 *ret
= USEC_INFINITY
;
1114 int varlink_flush(Varlink
*v
) {
1117 assert_return(v
, -EINVAL
);
1119 if (v
->state
== VARLINK_DISCONNECTED
)
1125 if (v
->output_buffer_size
== 0)
1127 if (v
->write_disconnected
)
1130 r
= varlink_write(v
);
1138 pfd
= (struct pollfd
) {
1143 if (poll(&pfd
, 1, -1) < 0)
1146 handle_revents(v
, pfd
.revents
);
1152 static void varlink_detach_server(Varlink
*v
) {
1158 if (v
->server
->by_uid
&&
1159 v
->ucred_acquired
&&
1160 uid_is_valid(v
->ucred
.uid
)) {
1163 c
= PTR_TO_UINT(hashmap_get(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
)));
1167 (void) hashmap_remove(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
));
1169 (void) hashmap_replace(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
), UINT_TO_PTR(c
- 1));
1172 assert(v
->server
->n_connections
> 0);
1173 v
->server
->n_connections
--;
1175 /* If this is a connection associated to a server, then let's disconnect the server and the
1176 * connection from each other. This drops the dangling reference that connect_callback() set up. */
1177 v
->server
= varlink_server_unref(v
->server
);
1181 int varlink_close(Varlink
*v
) {
1183 assert_return(v
, -EINVAL
);
1185 if (v
->state
== VARLINK_DISCONNECTED
)
1188 varlink_set_state(v
, VARLINK_DISCONNECTED
);
1190 /* Let's take a reference first, since varlink_detach_server() might drop the final (dangling) ref
1191 * which would destroy us before we can call varlink_clear() */
1193 varlink_detach_server(v
);
1200 Varlink
* varlink_flush_close_unref(Varlink
*v
) {
1205 (void) varlink_flush(v
);
1206 (void) varlink_close(v
);
1208 return varlink_unref(v
);
1211 static int varlink_enqueue_json(Varlink
*v
, JsonVariant
*m
) {
1212 _cleanup_free_
char *text
= NULL
;
1218 r
= json_variant_format(m
, 0, &text
);
1222 if (v
->output_buffer_size
+ r
+ 1 > VARLINK_BUFFER_MAX
)
1225 varlink_log(v
, "Sending message: %s", text
);
1227 if (v
->output_buffer_size
== 0) {
1229 free_and_replace(v
->output_buffer
, text
);
1231 v
->output_buffer_size
= v
->output_buffer_allocated
= r
+ 1;
1232 v
->output_buffer_index
= 0;
1234 } else if (v
->output_buffer_index
== 0) {
1236 if (!GREEDY_REALLOC(v
->output_buffer
, v
->output_buffer_allocated
, v
->output_buffer_size
+ r
+ 1))
1239 memcpy(v
->output_buffer
+ v
->output_buffer_size
, text
, r
+ 1);
1240 v
->output_buffer_size
+= r
+ 1;
1245 n
= new(char, v
->output_buffer_size
+ r
+ 1);
1249 memcpy(mempcpy(n
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
), text
, r
+ 1);
1251 free_and_replace(v
->output_buffer
, n
);
1252 v
->output_buffer_size
+= r
+ 1;
1253 v
->output_buffer_index
= 0;
1259 int varlink_send(Varlink
*v
, const char *method
, JsonVariant
*parameters
) {
1260 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1263 assert_return(v
, -EINVAL
);
1264 assert_return(method
, -EINVAL
);
1266 if (v
->state
== VARLINK_DISCONNECTED
)
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
)
1317 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
, VARLINK_AWAITING_REPLY
))
1320 r
= varlink_sanitize_parameters(¶meters
);
1324 r
= json_build(&m
, JSON_BUILD_OBJECT(
1325 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1326 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1330 r
= varlink_enqueue_json(v
, m
);
1334 varlink_set_state(v
, VARLINK_AWAITING_REPLY
);
1336 v
->timestamp
= now(CLOCK_MONOTONIC
);
1341 int varlink_invokeb(Varlink
*v
, const char *method
, ...) {
1342 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1346 assert_return(v
, -EINVAL
);
1348 va_start(ap
, method
);
1349 r
= json_buildv(¶meters
, ap
);
1355 return varlink_invoke(v
, method
, parameters
);
1361 JsonVariant
*parameters
,
1362 JsonVariant
**ret_parameters
,
1363 const char **ret_error_id
,
1364 VarlinkReplyFlags
*ret_flags
) {
1366 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1369 assert_return(v
, -EINVAL
);
1370 assert_return(method
, -EINVAL
);
1372 if (v
->state
== VARLINK_DISCONNECTED
)
1374 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
))
1377 assert(v
->n_pending
== 0); /* n_pending can't be > 0 if we are in VARLINK_IDLE_CLIENT state */
1379 r
= varlink_sanitize_parameters(¶meters
);
1383 r
= json_build(&m
, JSON_BUILD_OBJECT(
1384 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1385 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1389 r
= varlink_enqueue_json(v
, m
);
1393 varlink_set_state(v
, VARLINK_CALLING
);
1395 v
->timestamp
= now(CLOCK_MONOTONIC
);
1397 while (v
->state
== VARLINK_CALLING
) {
1399 r
= varlink_process(v
);
1405 r
= varlink_wait(v
, USEC_INFINITY
);
1412 case VARLINK_CALLED
:
1415 json_variant_unref(v
->reply
);
1416 v
->reply
= TAKE_PTR(v
->current
);
1418 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
1419 assert(v
->n_pending
== 1);
1423 *ret_parameters
= json_variant_by_key(v
->reply
, "parameters");
1425 *ret_error_id
= json_variant_string(json_variant_by_key(v
->reply
, "error"));
1431 case VARLINK_PENDING_DISCONNECT
:
1432 case VARLINK_DISCONNECTED
:
1435 case VARLINK_PENDING_TIMEOUT
:
1439 assert_not_reached("Unexpected state after method call.");
1446 JsonVariant
**ret_parameters
,
1447 const char **ret_error_id
,
1448 VarlinkReplyFlags
*ret_flags
, ...) {
1450 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1454 assert_return(v
, -EINVAL
);
1456 va_start(ap
, ret_flags
);
1457 r
= json_buildv(¶meters
, ap
);
1463 return varlink_call(v
, method
, parameters
, ret_parameters
, ret_error_id
, ret_flags
);
1466 int varlink_reply(Varlink
*v
, JsonVariant
*parameters
) {
1467 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1470 assert_return(v
, -EINVAL
);
1472 if (v
->state
== VARLINK_DISCONNECTED
)
1474 if (!IN_SET(v
->state
,
1475 VARLINK_PROCESSING_METHOD
, VARLINK_PROCESSING_METHOD_MORE
,
1476 VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
))
1479 r
= varlink_sanitize_parameters(¶meters
);
1483 r
= json_build(&m
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1487 r
= varlink_enqueue_json(v
, m
);
1491 if (IN_SET(v
->state
, VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
)) {
1492 /* We just replied to a method call that was let hanging for a while (i.e. we were outside of
1493 * the varlink_dispatch_method() stack frame), which means with this reply we are ready to
1494 * process further messages. */
1495 v
->current
= json_variant_unref(v
->current
);
1496 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
1498 /* We replied to a method call from within the varlink_dispatch_method() stack frame), which
1499 * means we should it handle the rest of the state engine. */
1500 varlink_set_state(v
, VARLINK_PROCESSED_METHOD
);
1505 int varlink_replyb(Varlink
*v
, ...) {
1506 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1510 assert_return(v
, -EINVAL
);
1513 r
= json_buildv(¶meters
, ap
);
1519 return varlink_reply(v
, parameters
);
1522 int varlink_error(Varlink
*v
, const char *error_id
, JsonVariant
*parameters
) {
1523 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1526 assert_return(v
, -EINVAL
);
1527 assert_return(error_id
, -EINVAL
);
1529 if (v
->state
== VARLINK_DISCONNECTED
)
1531 if (!IN_SET(v
->state
,
1532 VARLINK_PROCESSING_METHOD
, VARLINK_PROCESSING_METHOD_MORE
,
1533 VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
))
1536 r
= varlink_sanitize_parameters(¶meters
);
1540 r
= json_build(&m
, JSON_BUILD_OBJECT(
1541 JSON_BUILD_PAIR("error", JSON_BUILD_STRING(error_id
)),
1542 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1546 r
= varlink_enqueue_json(v
, m
);
1550 if (IN_SET(v
->state
, VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
)) {
1551 v
->current
= json_variant_unref(v
->current
);
1552 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
1554 varlink_set_state(v
, VARLINK_PROCESSED_METHOD
);
1559 int varlink_errorb(Varlink
*v
, const char *error_id
, ...) {
1560 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1564 assert_return(v
, -EINVAL
);
1565 assert_return(error_id
, -EINVAL
);
1567 va_start(ap
, error_id
);
1568 r
= json_buildv(¶meters
, ap
);
1574 return varlink_error(v
, error_id
, parameters
);
1577 int varlink_error_invalid_parameter(Varlink
*v
, JsonVariant
*parameters
) {
1579 assert_return(v
, -EINVAL
);
1580 assert_return(parameters
, -EINVAL
);
1582 /* We expect to be called in one of two ways: the 'parameters' argument is a string variant in which
1583 * case it is the parameter key name that is invalid. Or the 'parameters' argument is an object
1584 * variant in which case we'll pull out the first key. The latter mode is useful in functions that
1585 * don't expect any arguments. */
1587 if (json_variant_is_string(parameters
))
1588 return varlink_error(v
, VARLINK_ERROR_INVALID_PARAMETER
, parameters
);
1590 if (json_variant_is_object(parameters
) &&
1591 json_variant_elements(parameters
) > 0)
1592 return varlink_error(v
, VARLINK_ERROR_INVALID_PARAMETER
,
1593 json_variant_by_index(parameters
, 0));
1598 int varlink_notify(Varlink
*v
, JsonVariant
*parameters
) {
1599 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1602 assert_return(v
, -EINVAL
);
1604 if (v
->state
== VARLINK_DISCONNECTED
)
1606 if (!IN_SET(v
->state
, VARLINK_PROCESSING_METHOD_MORE
, VARLINK_PENDING_METHOD_MORE
))
1609 r
= varlink_sanitize_parameters(¶meters
);
1613 r
= json_build(&m
, JSON_BUILD_OBJECT(
1614 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
)),
1615 JSON_BUILD_PAIR("continues", JSON_BUILD_BOOLEAN(true))));
1619 r
= varlink_enqueue_json(v
, m
);
1623 /* No state change, as more is coming */
1627 int varlink_notifyb(Varlink
*v
, ...) {
1628 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1632 assert_return(v
, -EINVAL
);
1635 r
= json_buildv(¶meters
, ap
);
1641 return varlink_notify(v
, parameters
);
1644 int varlink_bind_reply(Varlink
*v
, VarlinkReply callback
) {
1645 assert_return(v
, -EINVAL
);
1647 if (callback
&& v
->reply_callback
&& callback
!= v
->reply_callback
)
1650 v
->reply_callback
= callback
;
1655 void* varlink_set_userdata(Varlink
*v
, void *userdata
) {
1658 assert_return(v
, NULL
);
1661 v
->userdata
= userdata
;
1666 void* varlink_get_userdata(Varlink
*v
) {
1667 assert_return(v
, NULL
);
1672 static int varlink_acquire_ucred(Varlink
*v
) {
1677 if (v
->ucred_acquired
)
1680 r
= getpeercred(v
->fd
, &v
->ucred
);
1684 v
->ucred_acquired
= true;
1688 int varlink_get_peer_uid(Varlink
*v
, uid_t
*ret
) {
1691 assert_return(v
, -EINVAL
);
1692 assert_return(ret
, -EINVAL
);
1694 r
= varlink_acquire_ucred(v
);
1698 if (!uid_is_valid(v
->ucred
.uid
))
1701 *ret
= v
->ucred
.uid
;
1705 int varlink_get_peer_pid(Varlink
*v
, pid_t
*ret
) {
1708 assert_return(v
, -EINVAL
);
1709 assert_return(ret
, -EINVAL
);
1711 r
= varlink_acquire_ucred(v
);
1715 if (!pid_is_valid(v
->ucred
.pid
))
1718 *ret
= v
->ucred
.pid
;
1722 int varlink_set_relative_timeout(Varlink
*v
, usec_t timeout
) {
1723 assert_return(v
, -EINVAL
);
1724 assert_return(timeout
> 0, -EINVAL
);
1726 v
->timeout
= timeout
;
1730 VarlinkServer
*varlink_get_server(Varlink
*v
) {
1731 assert_return(v
, NULL
);
1736 int varlink_set_description(Varlink
*v
, const char *description
) {
1737 assert_return(v
, -EINVAL
);
1739 return free_and_strdup(&v
->description
, description
);
1742 static int io_callback(sd_event_source
*s
, int fd
, uint32_t revents
, void *userdata
) {
1743 Varlink
*v
= userdata
;
1748 handle_revents(v
, revents
);
1749 (void) varlink_process(v
);
1754 static int time_callback(sd_event_source
*s
, uint64_t usec
, void *userdata
) {
1755 Varlink
*v
= userdata
;
1760 (void) varlink_process(v
);
1764 static int defer_callback(sd_event_source
*s
, void *userdata
) {
1765 Varlink
*v
= userdata
;
1770 (void) varlink_process(v
);
1774 static int prepare_callback(sd_event_source
*s
, void *userdata
) {
1775 Varlink
*v
= userdata
;
1782 e
= varlink_get_events(v
);
1786 r
= sd_event_source_set_io_events(v
->io_event_source
, e
);
1790 r
= varlink_get_timeout(v
, &until
);
1794 r
= sd_event_source_set_time(v
->time_event_source
, until
);
1799 r
= sd_event_source_set_enabled(v
->time_event_source
, r
> 0 ? SD_EVENT_ON
: SD_EVENT_OFF
);
1806 static int quit_callback(sd_event_source
*event
, void *userdata
) {
1807 Varlink
*v
= userdata
;
1818 int varlink_attach_event(Varlink
*v
, sd_event
*e
, int64_t priority
) {
1821 assert_return(v
, -EINVAL
);
1822 assert_return(!v
->event
, -EBUSY
);
1825 v
->event
= sd_event_ref(e
);
1827 r
= sd_event_default(&v
->event
);
1832 r
= sd_event_add_time(v
->event
, &v
->time_event_source
, CLOCK_MONOTONIC
, 0, 0, time_callback
, v
);
1836 r
= sd_event_source_set_priority(v
->time_event_source
, priority
);
1840 (void) sd_event_source_set_description(v
->time_event_source
, "varlink-time");
1842 r
= sd_event_add_exit(v
->event
, &v
->quit_event_source
, quit_callback
, v
);
1846 r
= sd_event_source_set_priority(v
->quit_event_source
, priority
);
1850 (void) sd_event_source_set_description(v
->quit_event_source
, "varlink-quit");
1852 r
= sd_event_add_io(v
->event
, &v
->io_event_source
, v
->fd
, 0, io_callback
, v
);
1856 r
= sd_event_source_set_prepare(v
->io_event_source
, prepare_callback
);
1860 r
= sd_event_source_set_priority(v
->io_event_source
, priority
);
1864 (void) sd_event_source_set_description(v
->io_event_source
, "varlink-io");
1866 r
= sd_event_add_defer(v
->event
, &v
->defer_event_source
, defer_callback
, v
);
1870 r
= sd_event_source_set_priority(v
->defer_event_source
, priority
);
1874 (void) sd_event_source_set_description(v
->defer_event_source
, "varlink-defer");
1879 varlink_detach_event(v
);
1884 void varlink_detach_event(Varlink
*v
) {
1888 varlink_detach_event_sources(v
);
1890 v
->event
= sd_event_unref(v
->event
);
1893 sd_event
*varlink_get_event(Varlink
*v
) {
1894 assert_return(v
, NULL
);
1899 int varlink_server_new(VarlinkServer
**ret
, VarlinkServerFlags flags
) {
1902 assert_return(ret
, -EINVAL
);
1903 assert_return((flags
& ~_VARLINK_SERVER_FLAGS_ALL
) == 0, -EINVAL
);
1905 s
= new(VarlinkServer
, 1);
1909 *s
= (VarlinkServer
) {
1912 .connections_max
= varlink_server_connections_max(NULL
),
1913 .connections_per_uid_max
= varlink_server_connections_per_uid_max(NULL
),
1920 static VarlinkServer
* varlink_server_destroy(VarlinkServer
*s
) {
1926 varlink_server_shutdown(s
);
1928 while ((m
= hashmap_steal_first_key(s
->methods
)))
1931 hashmap_free(s
->methods
);
1932 hashmap_free(s
->by_uid
);
1934 sd_event_unref(s
->event
);
1936 free(s
->description
);
1941 DEFINE_TRIVIAL_REF_UNREF_FUNC(VarlinkServer
, varlink_server
, varlink_server_destroy
);
1943 static int validate_connection(VarlinkServer
*server
, const struct ucred
*ucred
) {
1949 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ROOT_ONLY
))
1950 allowed
= ucred
->uid
== 0;
1952 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_MYSELF_ONLY
))
1953 allowed
= allowed
> 0 || ucred
->uid
== getuid();
1955 if (allowed
== 0) { /* Allow access when it is explicitly allowed or when neither
1956 * VARLINK_SERVER_ROOT_ONLY nor VARLINK_SERVER_MYSELF_ONLY are specified. */
1957 varlink_server_log(server
, "Unprivileged client attempted connection, refusing.");
1961 if (server
->n_connections
>= server
->connections_max
) {
1962 varlink_server_log(server
, "Connection limit of %u reached, refusing.", server
->connections_max
);
1966 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ACCOUNT_UID
)) {
1969 if (!uid_is_valid(ucred
->uid
)) {
1970 varlink_server_log(server
, "Client with invalid UID attempted connection, refusing.");
1974 c
= PTR_TO_UINT(hashmap_get(server
->by_uid
, UID_TO_PTR(ucred
->uid
)));
1975 if (c
>= server
->connections_per_uid_max
) {
1976 varlink_server_log(server
, "Per-UID connection limit of %u reached, refusing.",
1977 server
->connections_per_uid_max
);
1985 static int count_connection(VarlinkServer
*server
, struct ucred
*ucred
) {
1992 server
->n_connections
++;
1994 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ACCOUNT_UID
)) {
1995 r
= hashmap_ensure_allocated(&server
->by_uid
, NULL
);
1997 return log_debug_errno(r
, "Failed to allocate UID hash table: %m");
1999 c
= PTR_TO_UINT(hashmap_get(server
->by_uid
, UID_TO_PTR(ucred
->uid
)));
2001 varlink_server_log(server
, "Connections of user " UID_FMT
": %u (of %u max)",
2002 ucred
->uid
, c
, server
->connections_per_uid_max
);
2004 r
= hashmap_replace(server
->by_uid
, UID_TO_PTR(ucred
->uid
), UINT_TO_PTR(c
+ 1));
2006 return log_debug_errno(r
, "Failed to increment counter in UID hash table: %m");
2012 int varlink_server_add_connection(VarlinkServer
*server
, int fd
, Varlink
**ret
) {
2013 _cleanup_(varlink_unrefp
) Varlink
*v
= NULL
;
2014 bool ucred_acquired
;
2018 assert_return(server
, -EINVAL
);
2019 assert_return(fd
>= 0, -EBADF
);
2021 if ((server
->flags
& (VARLINK_SERVER_ROOT_ONLY
|VARLINK_SERVER_ACCOUNT_UID
)) != 0) {
2022 r
= getpeercred(fd
, &ucred
);
2024 return varlink_server_log_errno(server
, r
, "Failed to acquire peer credentials of incoming socket, refusing: %m");
2026 ucred_acquired
= true;
2028 r
= validate_connection(server
, &ucred
);
2034 ucred_acquired
= false;
2036 r
= varlink_new(&v
);
2038 return varlink_server_log_errno(server
, r
, "Failed to allocate connection object: %m");
2040 r
= count_connection(server
, &ucred
);
2045 v
->userdata
= server
->userdata
;
2046 if (ucred_acquired
) {
2048 v
->ucred_acquired
= true;
2051 (void) asprintf(&v
->description
, "%s-%i", server
->description
?: "varlink", v
->fd
);
2053 /* Link up the server and the connection, and take reference in both directions. Note that the
2054 * reference on the connection is left dangling. It will be dropped when the connection is closed,
2055 * which happens in varlink_close(), including in the event loop quit callback. */
2056 v
->server
= varlink_server_ref(server
);
2059 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
2061 r
= varlink_attach_event(v
, server
->event
, server
->event_priority
);
2063 varlink_log_errno(v
, r
, "Failed to attach new connection: %m");
2064 v
->fd
= -1; /* take the fd out of the connection again */
2075 static int connect_callback(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
2076 VarlinkServerSocket
*ss
= userdata
;
2077 _cleanup_close_
int cfd
= -1;
2084 varlink_server_log(ss
->server
, "New incoming connection.");
2086 cfd
= accept4(fd
, NULL
, NULL
, SOCK_NONBLOCK
|SOCK_CLOEXEC
);
2088 if (ERRNO_IS_ACCEPT_AGAIN(errno
))
2091 return varlink_server_log_errno(ss
->server
, errno
, "Failed to accept incoming socket: %m");
2094 r
= varlink_server_add_connection(ss
->server
, cfd
, &v
);
2100 if (ss
->server
->connect_callback
) {
2101 r
= ss
->server
->connect_callback(ss
->server
, v
, ss
->server
->userdata
);
2103 varlink_log_errno(v
, r
, "Connection callback returned error, disconnecting client: %m");
2112 int varlink_server_listen_fd(VarlinkServer
*s
, int fd
) {
2113 _cleanup_free_ VarlinkServerSocket
*ss
= NULL
;
2116 assert_return(s
, -EINVAL
);
2117 assert_return(fd
>= 0, -EBADF
);
2119 r
= fd_nonblock(fd
, true);
2123 ss
= new(VarlinkServerSocket
, 1);
2127 *ss
= (VarlinkServerSocket
) {
2133 _cleanup_(sd_event_source_unrefp
) sd_event_source
*es
= NULL
;
2135 r
= sd_event_add_io(s
->event
, &es
, fd
, EPOLLIN
, connect_callback
, ss
);
2139 r
= sd_event_source_set_priority(ss
->event_source
, s
->event_priority
);
2144 LIST_PREPEND(sockets
, s
->sockets
, TAKE_PTR(ss
));
2148 int varlink_server_listen_address(VarlinkServer
*s
, const char *address
, mode_t m
) {
2149 union sockaddr_union sockaddr
;
2150 _cleanup_close_
int fd
= -1;
2153 assert_return(s
, -EINVAL
);
2154 assert_return(address
, -EINVAL
);
2155 assert_return((m
& ~0777) == 0, -EINVAL
);
2157 r
= sockaddr_un_set_path(&sockaddr
.un
, address
);
2161 fd
= socket(AF_UNIX
, SOCK_STREAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
2165 (void) sockaddr_un_unlink(&sockaddr
.un
);
2167 RUN_WITH_UMASK(~m
& 0777)
2168 if (bind(fd
, &sockaddr
.sa
, SOCKADDR_UN_LEN(sockaddr
.un
)) < 0)
2171 if (listen(fd
, SOMAXCONN
) < 0)
2174 r
= varlink_server_listen_fd(s
, fd
);
2182 void* varlink_server_set_userdata(VarlinkServer
*s
, void *userdata
) {
2185 assert_return(s
, NULL
);
2188 s
->userdata
= userdata
;
2193 void* varlink_server_get_userdata(VarlinkServer
*s
) {
2194 assert_return(s
, NULL
);
2199 static VarlinkServerSocket
* varlink_server_socket_destroy(VarlinkServerSocket
*ss
) {
2204 LIST_REMOVE(sockets
, ss
->server
->sockets
, ss
);
2206 if (ss
->event_source
) {
2207 (void) sd_event_source_set_enabled(ss
->event_source
, SD_EVENT_OFF
);
2208 sd_event_source_unref(ss
->event_source
);
2217 int varlink_server_shutdown(VarlinkServer
*s
) {
2218 assert_return(s
, -EINVAL
);
2221 varlink_server_socket_destroy(s
->sockets
);
2226 int varlink_server_attach_event(VarlinkServer
*s
, sd_event
*e
, int64_t priority
) {
2227 VarlinkServerSocket
*ss
;
2230 assert_return(s
, -EINVAL
);
2231 assert_return(!s
->event
, -EBUSY
);
2234 s
->event
= sd_event_ref(e
);
2236 r
= sd_event_default(&s
->event
);
2241 LIST_FOREACH(sockets
, ss
, s
->sockets
) {
2242 assert(!ss
->event_source
);
2244 r
= sd_event_add_io(s
->event
, &ss
->event_source
, ss
->fd
, EPOLLIN
, connect_callback
, ss
);
2248 r
= sd_event_source_set_priority(ss
->event_source
, priority
);
2253 s
->event_priority
= priority
;
2257 varlink_server_detach_event(s
);
2261 int varlink_server_detach_event(VarlinkServer
*s
) {
2262 VarlinkServerSocket
*ss
;
2264 assert_return(s
, -EINVAL
);
2266 LIST_FOREACH(sockets
, ss
, s
->sockets
) {
2268 if (!ss
->event_source
)
2271 (void) sd_event_source_set_enabled(ss
->event_source
, SD_EVENT_OFF
);
2272 ss
->event_source
= sd_event_source_unref(ss
->event_source
);
2275 sd_event_unref(s
->event
);
2279 sd_event
*varlink_server_get_event(VarlinkServer
*s
) {
2280 assert_return(s
, NULL
);
2285 int varlink_server_bind_method(VarlinkServer
*s
, const char *method
, VarlinkMethod callback
) {
2289 assert_return(s
, -EINVAL
);
2290 assert_return(method
, -EINVAL
);
2291 assert_return(callback
, -EINVAL
);
2293 if (startswith(method
, "org.varlink.service."))
2296 r
= hashmap_ensure_allocated(&s
->methods
, &string_hash_ops
);
2304 r
= hashmap_put(s
->methods
, m
, callback
);
2313 int varlink_server_bind_method_many_internal(VarlinkServer
*s
, ...) {
2317 assert_return(s
, -EINVAL
);
2321 VarlinkMethod callback
;
2324 method
= va_arg(ap
, const char *);
2328 callback
= va_arg(ap
, VarlinkMethod
);
2330 r
= varlink_server_bind_method(s
, method
, callback
);
2338 int varlink_server_bind_connect(VarlinkServer
*s
, VarlinkConnect callback
) {
2339 assert_return(s
, -EINVAL
);
2341 if (callback
&& s
->connect_callback
&& callback
!= s
->connect_callback
)
2344 s
->connect_callback
= callback
;
2348 unsigned varlink_server_connections_max(VarlinkServer
*s
) {
2351 /* If a server is specified, return the setting for that server, otherwise the default value */
2353 return s
->connections_max
;
2355 assert_se(getrlimit(RLIMIT_NOFILE
, &rl
) >= 0);
2357 /* Make sure we never use up more than ¾th of RLIMIT_NOFILE for IPC */
2358 if (VARLINK_DEFAULT_CONNECTIONS_MAX
> rl
.rlim_cur
/ 4 * 3)
2359 return rl
.rlim_cur
/ 4 * 3;
2361 return VARLINK_DEFAULT_CONNECTIONS_MAX
;
2364 unsigned varlink_server_connections_per_uid_max(VarlinkServer
*s
) {
2368 return s
->connections_per_uid_max
;
2370 /* Make sure to never use up more than ¾th of available connections for a single user */
2371 m
= varlink_server_connections_max(NULL
);
2372 if (VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX
> m
)
2375 return VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX
;
2378 int varlink_server_set_connections_per_uid_max(VarlinkServer
*s
, unsigned m
) {
2379 assert_return(s
, -EINVAL
);
2380 assert_return(m
> 0, -EINVAL
);
2382 s
->connections_per_uid_max
= m
;
2386 int varlink_server_set_connections_max(VarlinkServer
*s
, unsigned m
) {
2387 assert_return(s
, -EINVAL
);
2388 assert_return(m
> 0, -EINVAL
);
2390 s
->connections_max
= m
;
2394 int varlink_server_set_description(VarlinkServer
*s
, const char *description
) {
2395 assert_return(s
, -EINVAL
);
2397 return free_and_strdup(&s
->description
, description
);