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
) {
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
) {
249 /* Here use new0 as the below structured initializer is nested. */
250 v
= new0(Varlink
, 1);
258 .state
= _VARLINK_STATE_INVALID
,
260 .ucred
.uid
= UID_INVALID
,
261 .ucred
.gid
= GID_INVALID
,
263 .timestamp
= USEC_INFINITY
,
264 .timeout
= VARLINK_DEFAULT_TIMEOUT_USEC
271 int varlink_connect_address(Varlink
**ret
, const char *address
) {
272 _cleanup_(varlink_unrefp
) Varlink
*v
= NULL
;
273 union sockaddr_union sockaddr
;
276 assert_return(ret
, -EINVAL
);
277 assert_return(address
, -EINVAL
);
279 r
= sockaddr_un_set_path(&sockaddr
.un
, address
);
287 v
->fd
= socket(AF_UNIX
, SOCK_STREAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
291 if (connect(v
->fd
, &sockaddr
.sa
, SOCKADDR_UN_LEN(sockaddr
.un
)) < 0) {
292 if (!IN_SET(errno
, EAGAIN
, EINPROGRESS
))
295 v
->connecting
= true; /* We are asynchronously connecting, i.e. the connect() is being
296 * processed in the background. As long as that's the case the socket
297 * is in a special state: it's there, we can poll it for EPOLLOUT, but
298 * if we attempt to write() to it before we see EPOLLOUT we'll get
299 * ENOTCONN (and not EAGAIN, like we would for a normal connected
300 * socket that isn't writable at the moment). Since ENOTCONN on write()
301 * hence can mean two different things (i.e. connection not complete
302 * yet vs. already disconnected again), we store as a boolean whether
303 * we are still in connect(). */
306 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
312 int varlink_connect_fd(Varlink
**ret
, int fd
) {
316 assert_return(ret
, -EINVAL
);
317 assert_return(fd
>= 0, -EBADF
);
319 r
= fd_nonblock(fd
, true);
328 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
330 /* Note that if this function is called we assume the passed socket (if it is one) is already
331 * properly connected, i.e. any asynchronous connect() done on it already completed. Because of that
332 * we'll not set the 'connecting' boolean here, i.e. we don't need to avoid write()ing to the socket
333 * until the connection is fully set up. Behaviour here is hence a bit different from
334 * varlink_connect_address() above, as there we do handle asynchronous connections ourselves and
335 * avoid doing write() on it before we saw EPOLLOUT for the first time. */
341 static void varlink_detach_event_sources(Varlink
*v
) {
344 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
);
348 v
->quit_event_source
= sd_event_source_disable_unref(v
->quit_event_source
);
350 v
->defer_event_source
= sd_event_source_disable_unref(v
->defer_event_source
);
353 static void varlink_clear(Varlink
*v
) {
356 varlink_detach_event_sources(v
);
358 v
->fd
= safe_close(v
->fd
);
360 v
->input_buffer
= mfree(v
->input_buffer
);
361 v
->output_buffer
= mfree(v
->output_buffer
);
363 v
->current
= json_variant_unref(v
->current
);
364 v
->reply
= json_variant_unref(v
->reply
);
366 v
->event
= sd_event_unref(v
->event
);
369 static Varlink
* varlink_destroy(Varlink
*v
) {
373 /* If this is called the server object must already been unreffed here. Why that? because when we
374 * linked up the varlink connection with the server object we took one ref in each direction */
379 free(v
->description
);
383 DEFINE_TRIVIAL_REF_UNREF_FUNC(Varlink
, varlink
, varlink_destroy
);
385 static int varlink_test_disconnect(Varlink
*v
) {
388 /* Tests whether we the the connection has been terminated. We are careful to not stop processing it
389 * prematurely, since we want to handle half-open connections as well as possible and want to flush
390 * out and read data before we close down if we can. */
392 /* Already disconnected? */
393 if (!VARLINK_STATE_IS_ALIVE(v
->state
))
396 /* Wait until connection setup is complete, i.e. until asynchronous connect() completes */
400 /* Still something to write and we can write? Stay around */
401 if (v
->output_buffer_size
> 0 && !v
->write_disconnected
)
404 /* Both sides gone already? Then there's no need to stick around */
405 if (v
->read_disconnected
&& v
->write_disconnected
)
408 /* If we are waiting for incoming data but the read side is shut down, disconnect. */
409 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
) && v
->read_disconnected
)
412 /* Similar, if are a client that hasn't written anything yet but the write side is dead, also
413 * disconnect. We also explicitly check for POLLHUP here since we likely won't notice the write side
414 * being down if we never wrote anything. */
415 if (IN_SET(v
->state
, VARLINK_IDLE_CLIENT
) && (v
->write_disconnected
|| v
->got_pollhup
))
421 varlink_set_state(v
, VARLINK_PENDING_DISCONNECT
);
425 static int varlink_write(Varlink
*v
) {
430 if (!VARLINK_STATE_IS_ALIVE(v
->state
))
432 if (v
->connecting
) /* Writing while we are still wait for a non-blocking connect() to complete will
433 * result in ENOTCONN, hence exit early here */
435 if (v
->output_buffer_size
== 0)
437 if (v
->write_disconnected
)
442 /* We generally prefer recv()/send() (mostly because of MSG_NOSIGNAL) but also want to be compatible
443 * with non-socket IO, hence fall back automatically */
444 if (!v
->prefer_read_write
) {
445 n
= send(v
->fd
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
, MSG_DONTWAIT
|MSG_NOSIGNAL
);
446 if (n
< 0 && errno
== ENOTSOCK
)
447 v
->prefer_read_write
= true;
449 if (v
->prefer_read_write
)
450 n
= write(v
->fd
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
);
455 if (ERRNO_IS_DISCONNECT(errno
)) {
456 /* If we get informed about a disconnect on write, then let's remember that, but not
457 * act on it just yet. Let's wait for read() to report the issue first. */
458 v
->write_disconnected
= true;
465 v
->output_buffer_size
-= n
;
467 if (v
->output_buffer_size
== 0)
468 v
->output_buffer_index
= 0;
470 v
->output_buffer_index
+= n
;
472 v
->timestamp
= now(CLOCK_MONOTONIC
);
476 static int varlink_read(Varlink
*v
) {
482 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
))
484 if (v
->connecting
) /* read() on a socket while we are in connect() will fail with EINVAL, hence exit early here */
488 if (v
->input_buffer_unscanned
> 0)
490 if (v
->read_disconnected
)
493 if (v
->input_buffer_size
>= VARLINK_BUFFER_MAX
)
498 if (v
->input_buffer_allocated
<= v
->input_buffer_index
+ v
->input_buffer_size
) {
501 add
= MIN(VARLINK_BUFFER_MAX
- v
->input_buffer_size
, VARLINK_READ_SIZE
);
503 if (v
->input_buffer_index
== 0) {
505 if (!GREEDY_REALLOC(v
->input_buffer
, v
->input_buffer_allocated
, v
->input_buffer_size
+ add
))
511 b
= new(char, v
->input_buffer_size
+ add
);
515 memcpy(b
, v
->input_buffer
+ v
->input_buffer_index
, v
->input_buffer_size
);
517 free_and_replace(v
->input_buffer
, b
);
519 v
->input_buffer_allocated
= v
->input_buffer_size
+ add
;
520 v
->input_buffer_index
= 0;
524 rs
= v
->input_buffer_allocated
- (v
->input_buffer_index
+ v
->input_buffer_size
);
526 if (!v
->prefer_read_write
) {
527 n
= recv(v
->fd
, v
->input_buffer
+ v
->input_buffer_index
+ v
->input_buffer_size
, rs
, MSG_DONTWAIT
);
528 if (n
< 0 && errno
== ENOTSOCK
)
529 v
->prefer_read_write
= true;
531 if (v
->prefer_read_write
)
532 n
= read(v
->fd
, v
->input_buffer
+ v
->input_buffer_index
+ v
->input_buffer_size
, rs
);
537 if (ERRNO_IS_DISCONNECT(errno
)) {
538 v
->read_disconnected
= true;
544 if (n
== 0) { /* EOF */
545 v
->read_disconnected
= true;
549 v
->input_buffer_size
+= n
;
550 v
->input_buffer_unscanned
+= n
;
555 static int varlink_parse_message(Varlink
*v
) {
556 const char *e
, *begin
;
564 if (v
->input_buffer_unscanned
<= 0)
567 assert(v
->input_buffer_unscanned
<= v
->input_buffer_size
);
568 assert(v
->input_buffer_index
+ v
->input_buffer_size
<= v
->input_buffer_allocated
);
570 begin
= v
->input_buffer
+ v
->input_buffer_index
;
572 e
= memchr(begin
+ v
->input_buffer_size
- v
->input_buffer_unscanned
, 0, v
->input_buffer_unscanned
);
574 v
->input_buffer_unscanned
= 0;
580 varlink_log(v
, "New incoming message: %s", begin
);
582 r
= json_parse(begin
, &v
->current
, NULL
, NULL
);
586 v
->input_buffer_size
-= sz
;
588 if (v
->input_buffer_size
== 0)
589 v
->input_buffer_index
= 0;
591 v
->input_buffer_index
+= sz
;
593 v
->input_buffer_unscanned
= v
->input_buffer_size
;
597 static int varlink_test_timeout(Varlink
*v
) {
600 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
))
602 if (v
->timeout
== USEC_INFINITY
)
605 if (now(CLOCK_MONOTONIC
) < usec_add(v
->timestamp
, v
->timeout
))
608 varlink_set_state(v
, VARLINK_PENDING_TIMEOUT
);
613 static int varlink_dispatch_local_error(Varlink
*v
, const char *error
) {
619 if (!v
->reply_callback
)
622 r
= v
->reply_callback(v
, NULL
, error
, VARLINK_REPLY_ERROR
|VARLINK_REPLY_LOCAL
, v
->userdata
);
624 log_debug_errno(r
, "Reply callback returned error, ignoring: %m");
629 static int varlink_dispatch_timeout(Varlink
*v
) {
632 if (v
->state
!= VARLINK_PENDING_TIMEOUT
)
635 varlink_set_state(v
, VARLINK_PROCESSING_TIMEOUT
);
636 varlink_dispatch_local_error(v
, VARLINK_ERROR_TIMEOUT
);
642 static int varlink_dispatch_disconnect(Varlink
*v
) {
645 if (v
->state
!= VARLINK_PENDING_DISCONNECT
)
648 varlink_set_state(v
, VARLINK_PROCESSING_DISCONNECT
);
649 varlink_dispatch_local_error(v
, VARLINK_ERROR_DISCONNECTED
);
655 static int varlink_sanitize_parameters(JsonVariant
**v
) {
658 /* Varlink always wants a parameters list, hence make one if the caller doesn't want any */
660 return json_variant_new_object(v
, NULL
, 0);
661 else if (!json_variant_is_object(*v
))
667 static int varlink_dispatch_reply(Varlink
*v
) {
668 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
669 VarlinkReplyFlags flags
= 0;
670 const char *error
= NULL
;
677 if (!IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
))
682 assert(v
->n_pending
> 0);
684 if (!json_variant_is_object(v
->current
))
687 JSON_VARIANT_OBJECT_FOREACH(k
, e
, v
->current
) {
689 if (streq(k
, "error")) {
692 if (!json_variant_is_string(e
))
695 error
= json_variant_string(e
);
696 flags
|= VARLINK_REPLY_ERROR
;
698 } else if (streq(k
, "parameters")) {
701 if (!json_variant_is_object(e
))
704 parameters
= json_variant_ref(e
);
706 } else if (streq(k
, "continues")) {
707 if (FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
710 if (!json_variant_is_boolean(e
))
713 if (json_variant_boolean(e
))
714 flags
|= VARLINK_REPLY_CONTINUES
;
719 if (error
&& FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
722 r
= varlink_sanitize_parameters(¶meters
);
726 if (v
->state
== VARLINK_AWAITING_REPLY
) {
727 varlink_set_state(v
, VARLINK_PROCESSING_REPLY
);
729 if (v
->reply_callback
) {
730 r
= v
->reply_callback(v
, parameters
, error
, flags
, v
->userdata
);
732 log_debug_errno(r
, "Reply callback returned error, ignoring: %m");
735 v
->current
= json_variant_unref(v
->current
);
737 if (v
->state
== VARLINK_PROCESSING_REPLY
) {
738 assert(v
->n_pending
> 0);
741 varlink_set_state(v
, v
->n_pending
== 0 ? VARLINK_IDLE_CLIENT
: VARLINK_AWAITING_REPLY
);
744 assert(v
->state
== VARLINK_CALLING
);
746 if (FLAGS_SET(flags
, VARLINK_REPLY_CONTINUES
))
749 varlink_set_state(v
, VARLINK_CALLED
);
755 varlink_set_state(v
, VARLINK_PROCESSING_FAILURE
);
756 varlink_dispatch_local_error(v
, VARLINK_ERROR_PROTOCOL
);
762 static int varlink_dispatch_method(Varlink
*v
) {
763 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
764 VarlinkMethodFlags flags
= 0;
765 const char *method
= NULL
, *error
;
767 VarlinkMethod callback
;
773 if (v
->state
!= VARLINK_IDLE_SERVER
)
778 if (!json_variant_is_object(v
->current
))
781 JSON_VARIANT_OBJECT_FOREACH(k
, e
, v
->current
) {
783 if (streq(k
, "method")) {
786 if (!json_variant_is_string(e
))
789 method
= json_variant_string(e
);
791 } else if (streq(k
, "parameters")) {
794 if (!json_variant_is_object(e
))
797 parameters
= json_variant_ref(e
);
799 } else if (streq(k
, "oneway")) {
801 if ((flags
& (VARLINK_METHOD_ONEWAY
|VARLINK_METHOD_MORE
)) != 0)
804 if (!json_variant_is_boolean(e
))
807 if (json_variant_boolean(e
))
808 flags
|= VARLINK_METHOD_ONEWAY
;
810 } else if (streq(k
, "more")) {
812 if ((flags
& (VARLINK_METHOD_ONEWAY
|VARLINK_METHOD_MORE
)) != 0)
815 if (!json_variant_is_boolean(e
))
818 if (json_variant_boolean(e
))
819 flags
|= VARLINK_METHOD_MORE
;
828 r
= varlink_sanitize_parameters(¶meters
);
832 varlink_set_state(v
, (flags
& VARLINK_METHOD_MORE
) ? VARLINK_PROCESSING_METHOD_MORE
:
833 (flags
& VARLINK_METHOD_ONEWAY
) ? VARLINK_PROCESSING_METHOD_ONEWAY
:
834 VARLINK_PROCESSING_METHOD
);
838 if (STR_IN_SET(method
, "org.varlink.service.GetInfo", "org.varlink.service.GetInterface")) {
839 /* For now, we don't implement a single of varlink's own methods */
841 error
= VARLINK_ERROR_METHOD_NOT_IMPLEMENTED
;
842 } else if (startswith(method
, "org.varlink.service.")) {
844 error
= VARLINK_ERROR_METHOD_NOT_FOUND
;
846 callback
= hashmap_get(v
->server
->methods
, method
);
847 error
= VARLINK_ERROR_METHOD_NOT_FOUND
;
851 r
= callback(v
, parameters
, flags
, v
->userdata
);
853 log_debug_errno(r
, "Callback for %s returned error: %m", method
);
855 /* We got an error back from the callback. Propagate it to the client if the method call remains unanswered. */
856 if (!FLAGS_SET(flags
, VARLINK_METHOD_ONEWAY
)) {
857 r
= varlink_errorb(v
, VARLINK_ERROR_SYSTEM
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("errno", JSON_BUILD_INTEGER(-r
))));
862 } else if (!FLAGS_SET(flags
, VARLINK_METHOD_ONEWAY
)) {
865 r
= varlink_errorb(v
, error
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
))));
872 case VARLINK_PROCESSED_METHOD
: /* Method call is fully processed */
873 case VARLINK_PROCESSING_METHOD_ONEWAY
: /* ditto */
874 v
->current
= json_variant_unref(v
->current
);
875 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
878 case VARLINK_PROCESSING_METHOD
: /* Method call wasn't replied to, will be replied to later */
879 varlink_set_state(v
, VARLINK_PENDING_METHOD
);
882 case VARLINK_PROCESSED_METHOD_MORE
: /* One reply for a "more" message was sent, more to come */
883 case VARLINK_PROCESSING_METHOD_MORE
: /* No reply for a "more" message was sent, more to come */
884 varlink_set_state(v
, VARLINK_PENDING_METHOD_MORE
);
888 assert_not_reached("Unexpected state");
898 varlink_set_state(v
, VARLINK_PROCESSING_FAILURE
);
899 varlink_dispatch_local_error(v
, VARLINK_ERROR_PROTOCOL
);
905 int varlink_process(Varlink
*v
) {
908 assert_return(v
, -EINVAL
);
910 if (v
->state
== VARLINK_DISCONNECTED
)
915 r
= varlink_write(v
);
919 r
= varlink_dispatch_reply(v
);
923 r
= varlink_dispatch_method(v
);
927 r
= varlink_parse_message(v
);
935 r
= varlink_test_disconnect(v
);
939 r
= varlink_dispatch_disconnect(v
);
943 r
= varlink_test_timeout(v
);
947 r
= varlink_dispatch_timeout(v
);
952 if (r
>= 0 && v
->defer_event_source
) {
955 /* If we did some processing, make sure we are called again soon */
956 q
= sd_event_source_set_enabled(v
->defer_event_source
, r
> 0 ? SD_EVENT_ON
: SD_EVENT_OFF
);
962 if (VARLINK_STATE_IS_ALIVE(v
->state
))
963 /* Initiate disconnection */
964 varlink_set_state(v
, VARLINK_PENDING_DISCONNECT
);
966 /* We failed while disconnecting, in that case close right away */
974 static void handle_revents(Varlink
*v
, int revents
) {
978 /* If we have seen POLLOUT or POLLHUP on a socket we are asynchronously waiting a connect()
979 * to complete on, we know we are ready. We don't read the connection error here though,
980 * we'll get the error on the next read() or write(). */
981 if ((revents
& (POLLOUT
|POLLHUP
)) == 0)
984 varlink_log(v
, "Anynchronous connection completed.");
985 v
->connecting
= false;
987 /* Note that we don't care much about POLLIN/POLLOUT here, we'll just try reading and writing
988 * what we can. However, we do care about POLLHUP to detect connection termination even if we
989 * momentarily don't want to read nor write anything. */
991 if (!FLAGS_SET(revents
, POLLHUP
))
994 varlink_log(v
, "Got POLLHUP from socket.");
995 v
->got_pollhup
= true;
999 int varlink_wait(Varlink
*v
, usec_t timeout
) {
1005 assert_return(v
, -EINVAL
);
1006 assert_return(!v
->server
, -ENOTTY
);
1008 if (v
->state
== VARLINK_DISCONNECTED
)
1011 r
= varlink_get_timeout(v
, &t
);
1014 if (t
!= USEC_INFINITY
) {
1017 n
= now(CLOCK_MONOTONIC
);
1021 t
= usec_sub_unsigned(t
, n
);
1024 if (timeout
!= USEC_INFINITY
&&
1025 (t
== USEC_INFINITY
|| timeout
< t
))
1028 fd
= varlink_get_fd(v
);
1032 events
= varlink_get_events(v
);
1036 pfd
= (struct pollfd
) {
1042 t
== USEC_INFINITY
? NULL
: timespec_store(&ts
, t
),
1047 handle_revents(v
, pfd
.revents
);
1049 return r
> 0 ? 1 : 0;
1052 int varlink_get_fd(Varlink
*v
) {
1054 assert_return(v
, -EINVAL
);
1056 if (v
->state
== VARLINK_DISCONNECTED
)
1064 int varlink_get_events(Varlink
*v
) {
1067 assert_return(v
, -EINVAL
);
1069 if (v
->state
== VARLINK_DISCONNECTED
)
1072 if (v
->connecting
) /* When processing an asynchronous connect(), we only wait for EPOLLOUT, which
1073 * tells us that the connection is now complete. Before that we should neither
1074 * write() or read() from the fd. */
1077 if (!v
->read_disconnected
&&
1078 IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
, VARLINK_IDLE_SERVER
) &&
1080 v
->input_buffer_unscanned
<= 0)
1083 if (!v
->write_disconnected
&&
1084 v
->output_buffer_size
> 0)
1090 int varlink_get_timeout(Varlink
*v
, usec_t
*ret
) {
1091 assert_return(v
, -EINVAL
);
1093 if (v
->state
== VARLINK_DISCONNECTED
)
1096 if (IN_SET(v
->state
, VARLINK_AWAITING_REPLY
, VARLINK_CALLING
) &&
1097 v
->timeout
!= USEC_INFINITY
) {
1099 *ret
= usec_add(v
->timestamp
, v
->timeout
);
1103 *ret
= USEC_INFINITY
;
1108 int varlink_flush(Varlink
*v
) {
1111 assert_return(v
, -EINVAL
);
1113 if (v
->state
== VARLINK_DISCONNECTED
)
1119 if (v
->output_buffer_size
== 0)
1121 if (v
->write_disconnected
)
1124 r
= varlink_write(v
);
1132 pfd
= (struct pollfd
) {
1137 if (poll(&pfd
, 1, -1) < 0)
1140 handle_revents(v
, pfd
.revents
);
1146 static void varlink_detach_server(Varlink
*v
) {
1152 if (v
->server
->by_uid
&&
1153 v
->ucred_acquired
&&
1154 uid_is_valid(v
->ucred
.uid
)) {
1157 c
= PTR_TO_UINT(hashmap_get(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
)));
1161 (void) hashmap_remove(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
));
1163 (void) hashmap_replace(v
->server
->by_uid
, UID_TO_PTR(v
->ucred
.uid
), UINT_TO_PTR(c
- 1));
1166 assert(v
->server
->n_connections
> 0);
1167 v
->server
->n_connections
--;
1169 /* If this is a connection associated to a server, then let's disconnect the server and the
1170 * connection from each other. This drops the dangling reference that connect_callback() set up. */
1171 v
->server
= varlink_server_unref(v
->server
);
1175 int varlink_close(Varlink
*v
) {
1177 assert_return(v
, -EINVAL
);
1179 if (v
->state
== VARLINK_DISCONNECTED
)
1182 varlink_set_state(v
, VARLINK_DISCONNECTED
);
1184 /* Let's take a reference first, since varlink_detach_server() might drop the final (dangling) ref
1185 * which would destroy us before we can call varlink_clear() */
1187 varlink_detach_server(v
);
1194 Varlink
* varlink_flush_close_unref(Varlink
*v
) {
1199 (void) varlink_flush(v
);
1200 (void) varlink_close(v
);
1202 return varlink_unref(v
);
1205 static int varlink_enqueue_json(Varlink
*v
, JsonVariant
*m
) {
1206 _cleanup_free_
char *text
= NULL
;
1212 r
= json_variant_format(m
, 0, &text
);
1216 if (v
->output_buffer_size
+ r
+ 1 > VARLINK_BUFFER_MAX
)
1219 varlink_log(v
, "Sending message: %s", text
);
1221 if (v
->output_buffer_size
== 0) {
1223 free_and_replace(v
->output_buffer
, text
);
1225 v
->output_buffer_size
= v
->output_buffer_allocated
= r
+ 1;
1226 v
->output_buffer_index
= 0;
1228 } else if (v
->output_buffer_index
== 0) {
1230 if (!GREEDY_REALLOC(v
->output_buffer
, v
->output_buffer_allocated
, v
->output_buffer_size
+ r
+ 1))
1233 memcpy(v
->output_buffer
+ v
->output_buffer_size
, text
, r
+ 1);
1234 v
->output_buffer_size
+= r
+ 1;
1239 n
= new(char, v
->output_buffer_size
+ r
+ 1);
1243 memcpy(mempcpy(n
, v
->output_buffer
+ v
->output_buffer_index
, v
->output_buffer_size
), text
, r
+ 1);
1245 free_and_replace(v
->output_buffer
, n
);
1246 v
->output_buffer_size
+= r
+ 1;
1247 v
->output_buffer_index
= 0;
1253 int varlink_send(Varlink
*v
, const char *method
, JsonVariant
*parameters
) {
1254 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1257 assert_return(v
, -EINVAL
);
1258 assert_return(method
, -EINVAL
);
1260 if (v
->state
== VARLINK_DISCONNECTED
)
1262 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
, VARLINK_AWAITING_REPLY
))
1265 r
= varlink_sanitize_parameters(¶meters
);
1269 r
= json_build(&m
, JSON_BUILD_OBJECT(
1270 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1271 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
)),
1272 JSON_BUILD_PAIR("oneway", JSON_BUILD_BOOLEAN(true))));
1276 r
= varlink_enqueue_json(v
, m
);
1280 /* No state change here, this is one-way only after all */
1281 v
->timestamp
= now(CLOCK_MONOTONIC
);
1285 int varlink_sendb(Varlink
*v
, const char *method
, ...) {
1286 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1290 assert_return(v
, -EINVAL
);
1292 va_start(ap
, method
);
1293 r
= json_buildv(¶meters
, ap
);
1299 return varlink_send(v
, method
, parameters
);
1302 int varlink_invoke(Varlink
*v
, const char *method
, JsonVariant
*parameters
) {
1303 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1306 assert_return(v
, -EINVAL
);
1307 assert_return(method
, -EINVAL
);
1309 if (v
->state
== VARLINK_DISCONNECTED
)
1311 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
, VARLINK_AWAITING_REPLY
))
1314 r
= varlink_sanitize_parameters(¶meters
);
1318 r
= json_build(&m
, JSON_BUILD_OBJECT(
1319 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1320 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1324 r
= varlink_enqueue_json(v
, m
);
1328 varlink_set_state(v
, VARLINK_AWAITING_REPLY
);
1330 v
->timestamp
= now(CLOCK_MONOTONIC
);
1335 int varlink_invokeb(Varlink
*v
, const char *method
, ...) {
1336 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1340 assert_return(v
, -EINVAL
);
1342 va_start(ap
, method
);
1343 r
= json_buildv(¶meters
, ap
);
1349 return varlink_invoke(v
, method
, parameters
);
1355 JsonVariant
*parameters
,
1356 JsonVariant
**ret_parameters
,
1357 const char **ret_error_id
,
1358 VarlinkReplyFlags
*ret_flags
) {
1360 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1363 assert_return(v
, -EINVAL
);
1364 assert_return(method
, -EINVAL
);
1366 if (v
->state
== VARLINK_DISCONNECTED
)
1368 if (!IN_SET(v
->state
, VARLINK_IDLE_CLIENT
))
1371 assert(v
->n_pending
== 0); /* n_pending can't be > 0 if we are in VARLINK_IDLE_CLIENT state */
1373 r
= varlink_sanitize_parameters(¶meters
);
1377 r
= json_build(&m
, JSON_BUILD_OBJECT(
1378 JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method
)),
1379 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1383 r
= varlink_enqueue_json(v
, m
);
1387 varlink_set_state(v
, VARLINK_CALLING
);
1389 v
->timestamp
= now(CLOCK_MONOTONIC
);
1391 while (v
->state
== VARLINK_CALLING
) {
1393 r
= varlink_process(v
);
1399 r
= varlink_wait(v
, USEC_INFINITY
);
1406 case VARLINK_CALLED
:
1409 json_variant_unref(v
->reply
);
1410 v
->reply
= TAKE_PTR(v
->current
);
1412 varlink_set_state(v
, VARLINK_IDLE_CLIENT
);
1413 assert(v
->n_pending
== 1);
1417 *ret_parameters
= json_variant_by_key(v
->reply
, "parameters");
1419 *ret_error_id
= json_variant_string(json_variant_by_key(v
->reply
, "error"));
1425 case VARLINK_PENDING_DISCONNECT
:
1426 case VARLINK_DISCONNECTED
:
1429 case VARLINK_PENDING_TIMEOUT
:
1433 assert_not_reached("Unexpected state after method call.");
1440 JsonVariant
**ret_parameters
,
1441 const char **ret_error_id
,
1442 VarlinkReplyFlags
*ret_flags
, ...) {
1444 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1448 assert_return(v
, -EINVAL
);
1450 va_start(ap
, ret_flags
);
1451 r
= json_buildv(¶meters
, ap
);
1457 return varlink_call(v
, method
, parameters
, ret_parameters
, ret_error_id
, ret_flags
);
1460 int varlink_reply(Varlink
*v
, JsonVariant
*parameters
) {
1461 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1464 assert_return(v
, -EINVAL
);
1466 if (v
->state
== VARLINK_DISCONNECTED
)
1468 if (!IN_SET(v
->state
,
1469 VARLINK_PROCESSING_METHOD
, VARLINK_PROCESSING_METHOD_MORE
,
1470 VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
))
1473 r
= varlink_sanitize_parameters(¶meters
);
1477 r
= json_build(&m
, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1481 r
= varlink_enqueue_json(v
, m
);
1485 if (IN_SET(v
->state
, VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
)) {
1486 /* We just replied to a method call that was let hanging for a while (i.e. we were outside of
1487 * the varlink_dispatch_method() stack frame), which means with this reply we are ready to
1488 * process further messages. */
1489 v
->current
= json_variant_unref(v
->current
);
1490 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
1492 /* We replied to a method call from within the varlink_dispatch_method() stack frame), which
1493 * means we should it handle the rest of the state engine. */
1494 varlink_set_state(v
, VARLINK_PROCESSED_METHOD
);
1499 int varlink_replyb(Varlink
*v
, ...) {
1500 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1504 assert_return(v
, -EINVAL
);
1507 r
= json_buildv(¶meters
, ap
);
1513 return varlink_reply(v
, parameters
);
1516 int varlink_error(Varlink
*v
, const char *error_id
, JsonVariant
*parameters
) {
1517 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1520 assert_return(v
, -EINVAL
);
1521 assert_return(error_id
, -EINVAL
);
1523 if (v
->state
== VARLINK_DISCONNECTED
)
1525 if (!IN_SET(v
->state
,
1526 VARLINK_PROCESSING_METHOD
, VARLINK_PROCESSING_METHOD_MORE
,
1527 VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
))
1530 r
= varlink_sanitize_parameters(¶meters
);
1534 r
= json_build(&m
, JSON_BUILD_OBJECT(
1535 JSON_BUILD_PAIR("error", JSON_BUILD_STRING(error_id
)),
1536 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
))));
1540 r
= varlink_enqueue_json(v
, m
);
1544 if (IN_SET(v
->state
, VARLINK_PENDING_METHOD
, VARLINK_PENDING_METHOD_MORE
)) {
1545 v
->current
= json_variant_unref(v
->current
);
1546 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
1548 varlink_set_state(v
, VARLINK_PROCESSED_METHOD
);
1553 int varlink_errorb(Varlink
*v
, const char *error_id
, ...) {
1554 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1558 assert_return(v
, -EINVAL
);
1559 assert_return(error_id
, -EINVAL
);
1561 va_start(ap
, error_id
);
1562 r
= json_buildv(¶meters
, ap
);
1568 return varlink_error(v
, error_id
, parameters
);
1571 int varlink_error_invalid_parameter(Varlink
*v
, JsonVariant
*parameters
) {
1573 assert_return(v
, -EINVAL
);
1574 assert_return(parameters
, -EINVAL
);
1576 /* We expect to be called in one of two ways: the 'parameters' argument is a string variant in which
1577 * case it is the parameter key name that is invalid. Or the 'parameters' argument is an object
1578 * variant in which case we'll pull out the first key. The latter mode is useful in functions that
1579 * don't expect any arguments. */
1581 if (json_variant_is_string(parameters
))
1582 return varlink_error(v
, VARLINK_ERROR_INVALID_PARAMETER
, parameters
);
1584 if (json_variant_is_object(parameters
) &&
1585 json_variant_elements(parameters
) > 0)
1586 return varlink_error(v
, VARLINK_ERROR_INVALID_PARAMETER
,
1587 json_variant_by_index(parameters
, 0));
1592 int varlink_notify(Varlink
*v
, JsonVariant
*parameters
) {
1593 _cleanup_(json_variant_unrefp
) JsonVariant
*m
= NULL
;
1596 assert_return(v
, -EINVAL
);
1598 if (v
->state
== VARLINK_DISCONNECTED
)
1600 if (!IN_SET(v
->state
, VARLINK_PROCESSING_METHOD_MORE
, VARLINK_PENDING_METHOD_MORE
))
1603 r
= varlink_sanitize_parameters(¶meters
);
1607 r
= json_build(&m
, JSON_BUILD_OBJECT(
1608 JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters
)),
1609 JSON_BUILD_PAIR("continues", JSON_BUILD_BOOLEAN(true))));
1613 r
= varlink_enqueue_json(v
, m
);
1617 /* No state change, as more is coming */
1621 int varlink_notifyb(Varlink
*v
, ...) {
1622 _cleanup_(json_variant_unrefp
) JsonVariant
*parameters
= NULL
;
1626 assert_return(v
, -EINVAL
);
1629 r
= json_buildv(¶meters
, ap
);
1635 return varlink_notify(v
, parameters
);
1638 int varlink_bind_reply(Varlink
*v
, VarlinkReply callback
) {
1639 assert_return(v
, -EINVAL
);
1641 if (callback
&& v
->reply_callback
&& callback
!= v
->reply_callback
)
1644 v
->reply_callback
= callback
;
1649 void* varlink_set_userdata(Varlink
*v
, void *userdata
) {
1652 assert_return(v
, NULL
);
1655 v
->userdata
= userdata
;
1660 void* varlink_get_userdata(Varlink
*v
) {
1661 assert_return(v
, NULL
);
1666 static int varlink_acquire_ucred(Varlink
*v
) {
1671 if (v
->ucred_acquired
)
1674 r
= getpeercred(v
->fd
, &v
->ucred
);
1678 v
->ucred_acquired
= true;
1682 int varlink_get_peer_uid(Varlink
*v
, uid_t
*ret
) {
1685 assert_return(v
, -EINVAL
);
1686 assert_return(ret
, -EINVAL
);
1688 r
= varlink_acquire_ucred(v
);
1692 if (!uid_is_valid(v
->ucred
.uid
))
1695 *ret
= v
->ucred
.uid
;
1699 int varlink_get_peer_pid(Varlink
*v
, pid_t
*ret
) {
1702 assert_return(v
, -EINVAL
);
1703 assert_return(ret
, -EINVAL
);
1705 r
= varlink_acquire_ucred(v
);
1709 if (!pid_is_valid(v
->ucred
.pid
))
1712 *ret
= v
->ucred
.pid
;
1716 int varlink_set_relative_timeout(Varlink
*v
, usec_t timeout
) {
1717 assert_return(v
, -EINVAL
);
1718 assert_return(timeout
> 0, -EINVAL
);
1720 v
->timeout
= timeout
;
1724 VarlinkServer
*varlink_get_server(Varlink
*v
) {
1725 assert_return(v
, NULL
);
1730 int varlink_set_description(Varlink
*v
, const char *description
) {
1731 assert_return(v
, -EINVAL
);
1733 return free_and_strdup(&v
->description
, description
);
1736 static int io_callback(sd_event_source
*s
, int fd
, uint32_t revents
, void *userdata
) {
1737 Varlink
*v
= userdata
;
1742 handle_revents(v
, revents
);
1743 (void) varlink_process(v
);
1748 static int time_callback(sd_event_source
*s
, uint64_t usec
, void *userdata
) {
1749 Varlink
*v
= userdata
;
1754 (void) varlink_process(v
);
1758 static int defer_callback(sd_event_source
*s
, void *userdata
) {
1759 Varlink
*v
= userdata
;
1764 (void) varlink_process(v
);
1768 static int prepare_callback(sd_event_source
*s
, void *userdata
) {
1769 Varlink
*v
= userdata
;
1776 e
= varlink_get_events(v
);
1780 r
= sd_event_source_set_io_events(v
->io_event_source
, e
);
1784 r
= varlink_get_timeout(v
, &until
);
1788 r
= sd_event_source_set_time(v
->time_event_source
, until
);
1793 r
= sd_event_source_set_enabled(v
->time_event_source
, r
> 0 ? SD_EVENT_ON
: SD_EVENT_OFF
);
1800 static int quit_callback(sd_event_source
*event
, void *userdata
) {
1801 Varlink
*v
= userdata
;
1812 int varlink_attach_event(Varlink
*v
, sd_event
*e
, int64_t priority
) {
1815 assert_return(v
, -EINVAL
);
1816 assert_return(!v
->event
, -EBUSY
);
1819 v
->event
= sd_event_ref(e
);
1821 r
= sd_event_default(&v
->event
);
1826 r
= sd_event_add_time(v
->event
, &v
->time_event_source
, CLOCK_MONOTONIC
, 0, 0, time_callback
, v
);
1830 r
= sd_event_source_set_priority(v
->time_event_source
, priority
);
1834 (void) sd_event_source_set_description(v
->time_event_source
, "varlink-time");
1836 r
= sd_event_add_exit(v
->event
, &v
->quit_event_source
, quit_callback
, v
);
1840 r
= sd_event_source_set_priority(v
->quit_event_source
, priority
);
1844 (void) sd_event_source_set_description(v
->quit_event_source
, "varlink-quit");
1846 r
= sd_event_add_io(v
->event
, &v
->io_event_source
, v
->fd
, 0, io_callback
, v
);
1850 r
= sd_event_source_set_prepare(v
->io_event_source
, prepare_callback
);
1854 r
= sd_event_source_set_priority(v
->io_event_source
, priority
);
1858 (void) sd_event_source_set_description(v
->io_event_source
, "varlink-io");
1860 r
= sd_event_add_defer(v
->event
, &v
->defer_event_source
, defer_callback
, v
);
1864 r
= sd_event_source_set_priority(v
->defer_event_source
, priority
);
1868 (void) sd_event_source_set_description(v
->defer_event_source
, "varlink-defer");
1873 varlink_detach_event(v
);
1878 void varlink_detach_event(Varlink
*v
) {
1882 varlink_detach_event_sources(v
);
1884 v
->event
= sd_event_unref(v
->event
);
1887 sd_event
*varlink_get_event(Varlink
*v
) {
1888 assert_return(v
, NULL
);
1893 int varlink_server_new(VarlinkServer
**ret
, VarlinkServerFlags flags
) {
1896 assert_return(ret
, -EINVAL
);
1897 assert_return((flags
& ~_VARLINK_SERVER_FLAGS_ALL
) == 0, -EINVAL
);
1899 s
= new(VarlinkServer
, 1);
1903 *s
= (VarlinkServer
) {
1906 .connections_max
= varlink_server_connections_max(NULL
),
1907 .connections_per_uid_max
= varlink_server_connections_per_uid_max(NULL
),
1914 static VarlinkServer
* varlink_server_destroy(VarlinkServer
*s
) {
1920 varlink_server_shutdown(s
);
1922 while ((m
= hashmap_steal_first_key(s
->methods
)))
1925 hashmap_free(s
->methods
);
1926 hashmap_free(s
->by_uid
);
1928 sd_event_unref(s
->event
);
1930 free(s
->description
);
1935 DEFINE_TRIVIAL_REF_UNREF_FUNC(VarlinkServer
, varlink_server
, varlink_server_destroy
);
1937 static int validate_connection(VarlinkServer
*server
, const struct ucred
*ucred
) {
1943 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ROOT_ONLY
))
1944 allowed
= ucred
->uid
== 0;
1946 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_MYSELF_ONLY
))
1947 allowed
= allowed
> 0 || ucred
->uid
== getuid();
1949 if (allowed
== 0) { /* Allow access when it is explicitly allowed or when neither
1950 * VARLINK_SERVER_ROOT_ONLY nor VARLINK_SERVER_MYSELF_ONLY are specified. */
1951 varlink_server_log(server
, "Unprivileged client attempted connection, refusing.");
1955 if (server
->n_connections
>= server
->connections_max
) {
1956 varlink_server_log(server
, "Connection limit of %u reached, refusing.", server
->connections_max
);
1960 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ACCOUNT_UID
)) {
1963 if (!uid_is_valid(ucred
->uid
)) {
1964 varlink_server_log(server
, "Client with invalid UID attempted connection, refusing.");
1968 c
= PTR_TO_UINT(hashmap_get(server
->by_uid
, UID_TO_PTR(ucred
->uid
)));
1969 if (c
>= server
->connections_per_uid_max
) {
1970 varlink_server_log(server
, "Per-UID connection limit of %u reached, refusing.",
1971 server
->connections_per_uid_max
);
1979 static int count_connection(VarlinkServer
*server
, struct ucred
*ucred
) {
1986 server
->n_connections
++;
1988 if (FLAGS_SET(server
->flags
, VARLINK_SERVER_ACCOUNT_UID
)) {
1989 r
= hashmap_ensure_allocated(&server
->by_uid
, NULL
);
1991 return log_debug_errno(r
, "Failed to allocate UID hash table: %m");
1993 c
= PTR_TO_UINT(hashmap_get(server
->by_uid
, UID_TO_PTR(ucred
->uid
)));
1995 varlink_server_log(server
, "Connections of user " UID_FMT
": %u (of %u max)",
1996 ucred
->uid
, c
, server
->connections_per_uid_max
);
1998 r
= hashmap_replace(server
->by_uid
, UID_TO_PTR(ucred
->uid
), UINT_TO_PTR(c
+ 1));
2000 return log_debug_errno(r
, "Failed to increment counter in UID hash table: %m");
2006 int varlink_server_add_connection(VarlinkServer
*server
, int fd
, Varlink
**ret
) {
2007 _cleanup_(varlink_unrefp
) Varlink
*v
= NULL
;
2008 bool ucred_acquired
;
2012 assert_return(server
, -EINVAL
);
2013 assert_return(fd
>= 0, -EBADF
);
2015 if ((server
->flags
& (VARLINK_SERVER_ROOT_ONLY
|VARLINK_SERVER_ACCOUNT_UID
)) != 0) {
2016 r
= getpeercred(fd
, &ucred
);
2018 return varlink_server_log_errno(server
, r
, "Failed to acquire peer credentials of incoming socket, refusing: %m");
2020 ucred_acquired
= true;
2022 r
= validate_connection(server
, &ucred
);
2028 ucred_acquired
= false;
2030 r
= varlink_new(&v
);
2032 return varlink_server_log_errno(server
, r
, "Failed to allocate connection object: %m");
2034 r
= count_connection(server
, &ucred
);
2039 v
->userdata
= server
->userdata
;
2040 if (ucred_acquired
) {
2042 v
->ucred_acquired
= true;
2045 (void) asprintf(&v
->description
, "%s-%i", server
->description
?: "varlink", v
->fd
);
2047 /* Link up the server and the connection, and take reference in both directions. Note that the
2048 * reference on the connection is left dangling. It will be dropped when the connection is closed,
2049 * which happens in varlink_close(), including in the event loop quit callback. */
2050 v
->server
= varlink_server_ref(server
);
2053 varlink_set_state(v
, VARLINK_IDLE_SERVER
);
2055 r
= varlink_attach_event(v
, server
->event
, server
->event_priority
);
2057 varlink_log_errno(v
, r
, "Failed to attach new connection: %m");
2058 v
->fd
= -1; /* take the fd out of the connection again */
2069 static int connect_callback(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
2070 VarlinkServerSocket
*ss
= userdata
;
2071 _cleanup_close_
int cfd
= -1;
2078 varlink_server_log(ss
->server
, "New incoming connection.");
2080 cfd
= accept4(fd
, NULL
, NULL
, SOCK_NONBLOCK
|SOCK_CLOEXEC
);
2082 if (ERRNO_IS_ACCEPT_AGAIN(errno
))
2085 return varlink_server_log_errno(ss
->server
, errno
, "Failed to accept incoming socket: %m");
2088 r
= varlink_server_add_connection(ss
->server
, cfd
, &v
);
2094 if (ss
->server
->connect_callback
) {
2095 r
= ss
->server
->connect_callback(ss
->server
, v
, ss
->server
->userdata
);
2097 varlink_log_errno(v
, r
, "Connection callback returned error, disconnecting client: %m");
2106 int varlink_server_listen_fd(VarlinkServer
*s
, int fd
) {
2107 _cleanup_free_ VarlinkServerSocket
*ss
= NULL
;
2110 assert_return(s
, -EINVAL
);
2111 assert_return(fd
>= 0, -EBADF
);
2113 r
= fd_nonblock(fd
, true);
2117 ss
= new(VarlinkServerSocket
, 1);
2121 *ss
= (VarlinkServerSocket
) {
2127 _cleanup_(sd_event_source_unrefp
) sd_event_source
*es
= NULL
;
2129 r
= sd_event_add_io(s
->event
, &es
, fd
, EPOLLIN
, connect_callback
, ss
);
2133 r
= sd_event_source_set_priority(ss
->event_source
, s
->event_priority
);
2138 LIST_PREPEND(sockets
, s
->sockets
, TAKE_PTR(ss
));
2142 int varlink_server_listen_address(VarlinkServer
*s
, const char *address
, mode_t m
) {
2143 union sockaddr_union sockaddr
;
2144 _cleanup_close_
int fd
= -1;
2147 assert_return(s
, -EINVAL
);
2148 assert_return(address
, -EINVAL
);
2149 assert_return((m
& ~0777) == 0, -EINVAL
);
2151 r
= sockaddr_un_set_path(&sockaddr
.un
, address
);
2155 fd
= socket(AF_UNIX
, SOCK_STREAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
2159 (void) sockaddr_un_unlink(&sockaddr
.un
);
2161 RUN_WITH_UMASK(~m
& 0777)
2162 if (bind(fd
, &sockaddr
.sa
, SOCKADDR_UN_LEN(sockaddr
.un
)) < 0)
2165 if (listen(fd
, SOMAXCONN
) < 0)
2168 r
= varlink_server_listen_fd(s
, fd
);
2176 void* varlink_server_set_userdata(VarlinkServer
*s
, void *userdata
) {
2179 assert_return(s
, NULL
);
2182 s
->userdata
= userdata
;
2187 void* varlink_server_get_userdata(VarlinkServer
*s
) {
2188 assert_return(s
, NULL
);
2193 static VarlinkServerSocket
* varlink_server_socket_destroy(VarlinkServerSocket
*ss
) {
2198 LIST_REMOVE(sockets
, ss
->server
->sockets
, ss
);
2200 sd_event_source_disable_unref(ss
->event_source
);
2208 int varlink_server_shutdown(VarlinkServer
*s
) {
2209 assert_return(s
, -EINVAL
);
2212 varlink_server_socket_destroy(s
->sockets
);
2217 int varlink_server_attach_event(VarlinkServer
*s
, sd_event
*e
, int64_t priority
) {
2218 VarlinkServerSocket
*ss
;
2221 assert_return(s
, -EINVAL
);
2222 assert_return(!s
->event
, -EBUSY
);
2225 s
->event
= sd_event_ref(e
);
2227 r
= sd_event_default(&s
->event
);
2232 LIST_FOREACH(sockets
, ss
, s
->sockets
) {
2233 assert(!ss
->event_source
);
2235 r
= sd_event_add_io(s
->event
, &ss
->event_source
, ss
->fd
, EPOLLIN
, connect_callback
, ss
);
2239 r
= sd_event_source_set_priority(ss
->event_source
, priority
);
2244 s
->event_priority
= priority
;
2248 varlink_server_detach_event(s
);
2252 int varlink_server_detach_event(VarlinkServer
*s
) {
2253 VarlinkServerSocket
*ss
;
2255 assert_return(s
, -EINVAL
);
2257 LIST_FOREACH(sockets
, ss
, s
->sockets
) {
2259 if (!ss
->event_source
)
2262 (void) sd_event_source_set_enabled(ss
->event_source
, SD_EVENT_OFF
);
2263 ss
->event_source
= sd_event_source_unref(ss
->event_source
);
2266 sd_event_unref(s
->event
);
2270 sd_event
*varlink_server_get_event(VarlinkServer
*s
) {
2271 assert_return(s
, NULL
);
2276 int varlink_server_bind_method(VarlinkServer
*s
, const char *method
, VarlinkMethod callback
) {
2280 assert_return(s
, -EINVAL
);
2281 assert_return(method
, -EINVAL
);
2282 assert_return(callback
, -EINVAL
);
2284 if (startswith(method
, "org.varlink.service."))
2287 r
= hashmap_ensure_allocated(&s
->methods
, &string_hash_ops
);
2295 r
= hashmap_put(s
->methods
, m
, callback
);
2304 int varlink_server_bind_method_many_internal(VarlinkServer
*s
, ...) {
2308 assert_return(s
, -EINVAL
);
2312 VarlinkMethod callback
;
2315 method
= va_arg(ap
, const char *);
2319 callback
= va_arg(ap
, VarlinkMethod
);
2321 r
= varlink_server_bind_method(s
, method
, callback
);
2329 int varlink_server_bind_connect(VarlinkServer
*s
, VarlinkConnect callback
) {
2330 assert_return(s
, -EINVAL
);
2332 if (callback
&& s
->connect_callback
&& callback
!= s
->connect_callback
)
2335 s
->connect_callback
= callback
;
2339 unsigned varlink_server_connections_max(VarlinkServer
*s
) {
2342 /* If a server is specified, return the setting for that server, otherwise the default value */
2344 return s
->connections_max
;
2346 assert_se(getrlimit(RLIMIT_NOFILE
, &rl
) >= 0);
2348 /* Make sure we never use up more than ¾th of RLIMIT_NOFILE for IPC */
2349 if (VARLINK_DEFAULT_CONNECTIONS_MAX
> rl
.rlim_cur
/ 4 * 3)
2350 return rl
.rlim_cur
/ 4 * 3;
2352 return VARLINK_DEFAULT_CONNECTIONS_MAX
;
2355 unsigned varlink_server_connections_per_uid_max(VarlinkServer
*s
) {
2359 return s
->connections_per_uid_max
;
2361 /* Make sure to never use up more than ¾th of available connections for a single user */
2362 m
= varlink_server_connections_max(NULL
);
2363 if (VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX
> m
)
2366 return VARLINK_DEFAULT_CONNECTIONS_PER_UID_MAX
;
2369 int varlink_server_set_connections_per_uid_max(VarlinkServer
*s
, unsigned m
) {
2370 assert_return(s
, -EINVAL
);
2371 assert_return(m
> 0, -EINVAL
);
2373 s
->connections_per_uid_max
= m
;
2377 int varlink_server_set_connections_max(VarlinkServer
*s
, unsigned m
) {
2378 assert_return(s
, -EINVAL
);
2379 assert_return(m
> 0, -EINVAL
);
2381 s
->connections_max
= m
;
2385 int varlink_server_set_description(VarlinkServer
*s
, const char *description
) {
2386 assert_return(s
, -EINVAL
);
2388 return free_and_strdup(&s
->description
, description
);