1 /*
2  * Copyright (C) 2004-2009, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 1998-2002  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id$ */
19 
20 #ifndef ISC_SOCKET_H
21 #define ISC_SOCKET_H 1
22 
23 /*****
24  ***** Module Info
25  *****/
26 
27 /*! \file isc/socket.h
28  * \brief Provides TCP and UDP sockets for network I/O.  The sockets are event
29  * sources in the task system.
30  *
31  * When I/O completes, a completion event for the socket is posted to the
32  * event queue of the task which requested the I/O.
33  *
34  * \li MP:
35  *	The module ensures appropriate synchronization of data structures it
36  *	creates and manipulates.
37  *	Clients of this module must not be holding a socket's task's lock when
38  *	making a call that affects that socket.  Failure to follow this rule
39  *	can result in deadlock.
40  *	The caller must ensure that isc_socketmgr_destroy() is called only
41  *	once for a given manager.
42  *
43  * \li Reliability:
44  *	No anticipated impact.
45  *
46  * \li Resources:
47  *	TBS
48  *
49  * \li Security:
50  *	No anticipated impact.
51  *
52  * \li Standards:
53  *	None.
54  */
55 
56 /***
57  *** Imports
58  ***/
59 
60 #include <isc/lang.h>
61 #include <isc/types.h>
62 #include <isc/event.h>
63 #include <isc/eventclass.h>
64 #include <isc/time.h>
65 #include <isc/region.h>
66 #include <isc/sockaddr.h>
67 #include <isc/xml.h>
68 
69 ISC_LANG_BEGINDECLS
70 
71 /***
72  *** Constants
73  ***/
74 
75 /*%
76  * Maximum number of buffers in a scatter/gather read/write.  The operating
77  * system in use must support at least this number (plus one on some.)
78  */
79 #define ISC_SOCKET_MAXSCATTERGATHER	8
80 
81 /*%
82  * In isc_socket_bind() set socket option SO_REUSEADDR prior to calling
83  * bind() if a non zero port is specified (AF_INET and AF_INET6).
84  */
85 #define ISC_SOCKET_REUSEADDRESS		0x01U
86 
87 /*%
88  * Statistics counters.  Used as isc_statscounter_t values.
89  */
90 enum {
91 	isc_sockstatscounter_udp4open = 0,
92 	isc_sockstatscounter_udp6open = 1,
93 	isc_sockstatscounter_tcp4open = 2,
94 	isc_sockstatscounter_tcp6open = 3,
95 	isc_sockstatscounter_unixopen = 4,
96 
97 	isc_sockstatscounter_udp4openfail = 5,
98 	isc_sockstatscounter_udp6openfail = 6,
99 	isc_sockstatscounter_tcp4openfail = 7,
100 	isc_sockstatscounter_tcp6openfail = 8,
101 	isc_sockstatscounter_unixopenfail = 9,
102 
103 	isc_sockstatscounter_udp4close = 10,
104 	isc_sockstatscounter_udp6close = 11,
105 	isc_sockstatscounter_tcp4close = 12,
106 	isc_sockstatscounter_tcp6close = 13,
107 	isc_sockstatscounter_unixclose = 14,
108 	isc_sockstatscounter_fdwatchclose = 15,
109 
110 	isc_sockstatscounter_udp4bindfail = 16,
111 	isc_sockstatscounter_udp6bindfail = 17,
112 	isc_sockstatscounter_tcp4bindfail = 18,
113 	isc_sockstatscounter_tcp6bindfail = 19,
114 	isc_sockstatscounter_unixbindfail = 20,
115 	isc_sockstatscounter_fdwatchbindfail = 21,
116 
117 	isc_sockstatscounter_udp4connect = 22,
118 	isc_sockstatscounter_udp6connect = 23,
119 	isc_sockstatscounter_tcp4connect = 24,
120 	isc_sockstatscounter_tcp6connect = 25,
121 	isc_sockstatscounter_unixconnect = 26,
122 	isc_sockstatscounter_fdwatchconnect = 27,
123 
124 	isc_sockstatscounter_udp4connectfail = 28,
125 	isc_sockstatscounter_udp6connectfail = 29,
126 	isc_sockstatscounter_tcp4connectfail = 30,
127 	isc_sockstatscounter_tcp6connectfail = 31,
128 	isc_sockstatscounter_unixconnectfail = 32,
129 	isc_sockstatscounter_fdwatchconnectfail = 33,
130 
131 	isc_sockstatscounter_tcp4accept = 34,
132 	isc_sockstatscounter_tcp6accept = 35,
133 	isc_sockstatscounter_unixaccept = 36,
134 
135 	isc_sockstatscounter_tcp4acceptfail = 37,
136 	isc_sockstatscounter_tcp6acceptfail = 38,
137 	isc_sockstatscounter_unixacceptfail = 39,
138 
139 	isc_sockstatscounter_udp4sendfail = 40,
140 	isc_sockstatscounter_udp6sendfail = 41,
141 	isc_sockstatscounter_tcp4sendfail = 42,
142 	isc_sockstatscounter_tcp6sendfail = 43,
143 	isc_sockstatscounter_unixsendfail = 44,
144 	isc_sockstatscounter_fdwatchsendfail = 45,
145 
146 	isc_sockstatscounter_udp4recvfail = 46,
147 	isc_sockstatscounter_udp6recvfail = 47,
148 	isc_sockstatscounter_tcp4recvfail = 48,
149 	isc_sockstatscounter_tcp6recvfail = 49,
150 	isc_sockstatscounter_unixrecvfail = 50,
151 	isc_sockstatscounter_fdwatchrecvfail = 51,
152 
153 	isc_sockstatscounter_max = 52
154 };
155 
156 /***
157  *** Types
158  ***/
159 
160 struct isc_socketevent {
161 	ISC_EVENT_COMMON(isc_socketevent_t);
162 	isc_result_t		result;		/*%< OK, EOF, whatever else */
163 	unsigned int		minimum;	/*%< minimum i/o for event */
164 	unsigned int		n;		/*%< bytes read or written */
165 	unsigned int		offset;		/*%< offset into buffer list */
166 	isc_region_t		region;		/*%< for single-buffer i/o */
167 	isc_bufferlist_t	bufferlist;	/*%< list of buffers */
168 	isc_sockaddr_t		address;	/*%< source address */
169 	isc_time_t		timestamp;	/*%< timestamp of packet recv */
170 	struct in6_pktinfo	pktinfo;	/*%< ipv6 pktinfo */
171 	isc_uint32_t		attributes;	/*%< see below */
172 	isc_eventdestructor_t   destroy;	/*%< original destructor */
173 };
174 
175 typedef struct isc_socket_newconnev isc_socket_newconnev_t;
176 struct isc_socket_newconnev {
177 	ISC_EVENT_COMMON(isc_socket_newconnev_t);
178 	isc_socket_t *		newsocket;
179 	isc_result_t		result;		/*%< OK, EOF, whatever else */
180 	isc_sockaddr_t		address;	/*%< source address */
181 };
182 
183 typedef struct isc_socket_connev isc_socket_connev_t;
184 struct isc_socket_connev {
185 	ISC_EVENT_COMMON(isc_socket_connev_t);
186 	isc_result_t		result;		/*%< OK, EOF, whatever else */
187 };
188 
189 /*@{*/
190 /*!
191  * _ATTACHED:	Internal use only.
192  * _TRUNC:	Packet was truncated on receive.
193  * _CTRUNC:	Packet control information was truncated.  This can
194  *		indicate that the packet is not complete, even though
195  *		all the data is valid.
196  * _TIMESTAMP:	The timestamp member is valid.
197  * _PKTINFO:	The pktinfo member is valid.
198  * _MULTICAST:	The UDP packet was received via a multicast transmission.
199  */
200 #define ISC_SOCKEVENTATTR_ATTACHED		0x80000000U /* internal */
201 #define ISC_SOCKEVENTATTR_TRUNC			0x00800000U /* public */
202 #define ISC_SOCKEVENTATTR_CTRUNC		0x00400000U /* public */
203 #define ISC_SOCKEVENTATTR_TIMESTAMP		0x00200000U /* public */
204 #define ISC_SOCKEVENTATTR_PKTINFO		0x00100000U /* public */
205 #define ISC_SOCKEVENTATTR_MULTICAST		0x00080000U /* public */
206 /*@}*/
207 
208 #define ISC_SOCKEVENT_ANYEVENT  (0)
209 #define ISC_SOCKEVENT_RECVDONE	(ISC_EVENTCLASS_SOCKET + 1)
210 #define ISC_SOCKEVENT_SENDDONE	(ISC_EVENTCLASS_SOCKET + 2)
211 #define ISC_SOCKEVENT_NEWCONN	(ISC_EVENTCLASS_SOCKET + 3)
212 #define ISC_SOCKEVENT_CONNECT	(ISC_EVENTCLASS_SOCKET + 4)
213 
214 /*
215  * Internal events.
216  */
217 #define ISC_SOCKEVENT_INTR	(ISC_EVENTCLASS_SOCKET + 256)
218 #define ISC_SOCKEVENT_INTW	(ISC_EVENTCLASS_SOCKET + 257)
219 
220 typedef enum {
221 	isc_sockettype_udp = 1,
222 	isc_sockettype_tcp = 2,
223 	isc_sockettype_unix = 3,
224 	isc_sockettype_fdwatch = 4
225 } isc_sockettype_t;
226 
227 /*@{*/
228 /*!
229  * How a socket should be shutdown in isc_socket_shutdown() calls.
230  */
231 #define ISC_SOCKSHUT_RECV	0x00000001	/*%< close read side */
232 #define ISC_SOCKSHUT_SEND	0x00000002	/*%< close write side */
233 #define ISC_SOCKSHUT_ALL	0x00000003	/*%< close them all */
234 /*@}*/
235 
236 /*@{*/
237 /*!
238  * What I/O events to cancel in isc_socket_cancel() calls.
239  */
240 #define ISC_SOCKCANCEL_RECV	0x00000001	/*%< cancel recv */
241 #define ISC_SOCKCANCEL_SEND	0x00000002	/*%< cancel send */
242 #define ISC_SOCKCANCEL_ACCEPT	0x00000004	/*%< cancel accept */
243 #define ISC_SOCKCANCEL_CONNECT	0x00000008	/*%< cancel connect */
244 #define ISC_SOCKCANCEL_ALL	0x0000000f	/*%< cancel everything */
245 /*@}*/
246 
247 /*@{*/
248 /*!
249  * Flags for isc_socket_send() and isc_socket_recv() calls.
250  */
251 #define ISC_SOCKFLAG_IMMEDIATE	0x00000001	/*%< send event only if needed */
252 #define ISC_SOCKFLAG_NORETRY	0x00000002	/*%< drop failed UDP sends */
253 /*@}*/
254 
255 /*@{*/
256 /*!
257  * Flags for fdwatchcreate.
258  */
259 #define ISC_SOCKFDWATCH_READ	0x00000001	/*%< watch for readable */
260 #define ISC_SOCKFDWATCH_WRITE	0x00000002	/*%< watch for writable */
261 /*@}*/
262 
263 /*% Socket and socket manager methods */
264 typedef struct isc_socketmgrmethods {
265 	void		(*destroy)(isc_socketmgr_t **managerp);
266 	isc_result_t	(*socketcreate)(isc_socketmgr_t *manager, int pf,
267 					isc_sockettype_t type,
268 					isc_socket_t **socketp);
269 	isc_result_t    (*fdwatchcreate)(isc_socketmgr_t *manager, int fd,
270 					 int flags,
271 					 isc_sockfdwatch_t callback,
272 					 void *cbarg, isc_task_t *task,
273 					 isc_socket_t **socketp);
274 } isc_socketmgrmethods_t;
275 
276 typedef struct isc_socketmethods {
277 	void		(*attach)(isc_socket_t *sock,
278 				  isc_socket_t **socketp);
279 	void		(*detach)(isc_socket_t **socketp);
280 	isc_result_t	(*bind)(isc_socket_t *sock, isc_sockaddr_t *sockaddr,
281 				unsigned int options);
282 	isc_result_t	(*sendto)(isc_socket_t *sock, isc_region_t *region,
283 				  isc_task_t *task, isc_taskaction_t action,
284 				  const void *arg, isc_sockaddr_t *address,
285 				  struct in6_pktinfo *pktinfo);
286 	isc_result_t	(*connect)(isc_socket_t *sock, isc_sockaddr_t *addr,
287 				   isc_task_t *task, isc_taskaction_t action,
288 				   const void *arg);
289 	isc_result_t	(*recv)(isc_socket_t *sock, isc_region_t *region,
290 				unsigned int minimum, isc_task_t *task,
291 				isc_taskaction_t action, const void *arg);
292 	void		(*cancel)(isc_socket_t *sock, isc_task_t *task,
293 				  unsigned int how);
294 	isc_result_t	(*getsockname)(isc_socket_t *sock,
295 				       isc_sockaddr_t *addressp);
296 	isc_sockettype_t (*gettype)(isc_socket_t *sock);
297 	void		(*ipv6only)(isc_socket_t *sock, isc_boolean_t yes);
298 	isc_result_t    (*fdwatchpoke)(isc_socket_t *sock, int flags);
299 	isc_result_t		(*dup)(isc_socket_t *sock,
300 				  isc_socket_t **socketp);
301 	int 		(*getfd)(isc_socket_t *sock);
302 } isc_socketmethods_t;
303 
304 /*%
305  * This structure is actually just the common prefix of a socket manager
306  * object implementation's version of an isc_socketmgr_t.
307  * \brief
308  * Direct use of this structure by clients is forbidden.  socket implementations
309  * may change the structure.  'magic' must be ISCAPI_SOCKETMGR_MAGIC for any
310  * of the isc_socket_ routines to work.  socket implementations must maintain
311  * all socket invariants.
312  * In effect, this definition is used only for non-BIND9 version ("export")
313  * of the library, and the export version does not work for win32.  So, to avoid
314  * the definition conflict with win32/socket.c, we enable this definition only
315  * for non-Win32 (i.e. Unix) platforms.
316  */
317 #ifndef WIN32
318 struct isc_socketmgr {
319 	unsigned int		impmagic;
320 	unsigned int		magic;
321 	isc_socketmgrmethods_t	*methods;
322 };
323 #endif
324 
325 #define ISCAPI_SOCKETMGR_MAGIC		ISC_MAGIC('A','s','m','g')
326 #define ISCAPI_SOCKETMGR_VALID(m)	((m) != NULL && \
327 					 (m)->magic == ISCAPI_SOCKETMGR_MAGIC)
328 
329 /*%
330  * This is the common prefix of a socket object.  The same note as
331  * that for the socketmgr structure applies.
332  */
333 #ifndef WIN32
334 struct isc_socket {
335 	unsigned int		impmagic;
336 	unsigned int		magic;
337 	isc_socketmethods_t	*methods;
338 };
339 #endif
340 
341 #define ISCAPI_SOCKET_MAGIC	ISC_MAGIC('A','s','c','t')
342 #define ISCAPI_SOCKET_VALID(s)	((s) != NULL && \
343 				 (s)->magic == ISCAPI_SOCKET_MAGIC)
344 
345 /***
346  *** Socket and Socket Manager Functions
347  ***
348  *** Note: all Ensures conditions apply only if the result is success for
349  *** those functions which return an isc_result.
350  ***/
351 
352 isc_result_t
353 isc_socket_fdwatchcreate(isc_socketmgr_t *manager,
354 			 int fd,
355 			 int flags,
356 			 isc_sockfdwatch_t callback,
357 			 void *cbarg,
358 			 isc_task_t *task,
359 			 isc_socket_t **socketp);
360 /*%<
361  * Create a new file descriptor watch socket managed by 'manager'.
362  *
363  * Note:
364  *
365  *\li   'fd' is the already-opened file descriptor.
366  *\li	This function is not available on Windows.
367  *\li	The callback function is called "in-line" - this means the function
368  *	needs to return as fast as possible, as all other I/O will be suspended
369  *	until the callback completes.
370  *
371  * Requires:
372  *
373  *\li	'manager' is a valid manager
374  *
375  *\li	'socketp' is a valid pointer, and *socketp == NULL
376  *
377  *\li	'fd' be opened.
378  *
379  * Ensures:
380  *
381  *	'*socketp' is attached to the newly created fdwatch socket
382  *
383  * Returns:
384  *
385  *\li	#ISC_R_SUCCESS
386  *\li	#ISC_R_NOMEMORY
387  *\li	#ISC_R_NORESOURCES
388  *\li	#ISC_R_UNEXPECTED
389  */
390 
391 isc_result_t
392 isc_socket_fdwatchpoke(isc_socket_t *sock,
393 		       int flags);
394 /*%<
395  * Poke a file descriptor watch socket informing the manager that it
396  * should restart watching the socket
397  *
398  * Note:
399  *
400  *\li   'sock' is the socket returned by isc_socket_fdwatchcreate
401  *
402  *\li   'flags' indicates what the manager should watch for on the socket
403  *      in addition to what it may already be watching.  It can be one or
404  *      both of ISC_SOCKFDWATCH_READ and ISC_SOCKFDWATCH_WRITE.  To
405  *      temporarily disable watching on a socket the value indicating
406  *      no more data should be returned from the call back routine.
407  *
408  *\li	This function is not available on Windows.
409  *
410  * Requires:
411  *
412  *\li	'sock' is a valid isc socket
413  *
414  *
415  * Returns:
416  *
417  *\li	#ISC_R_SUCCESS
418  */
419 
420 isc_result_t
421 isc_socket_create(isc_socketmgr_t *manager,
422 		  int pf,
423 		  isc_sockettype_t type,
424 		  isc_socket_t **socketp);
425 /*%<
426  * Create a new 'type' socket managed by 'manager'.
427  *
428  * For isc_sockettype_fdwatch sockets you should use isc_socket_fdwatchcreate()
429  * rather than isc_socket_create().
430  *
431  * Note:
432  *
433  *\li	'pf' is the desired protocol family, e.g. PF_INET or PF_INET6.
434  *
435  * Requires:
436  *
437  *\li	'manager' is a valid manager
438  *
439  *\li	'socketp' is a valid pointer, and *socketp == NULL
440  *
441  *\li	'type' is not isc_sockettype_fdwatch
442  *
443  * Ensures:
444  *
445  *	'*socketp' is attached to the newly created socket
446  *
447  * Returns:
448  *
449  *\li	#ISC_R_SUCCESS
450  *\li	#ISC_R_NOMEMORY
451  *\li	#ISC_R_NORESOURCES
452  *\li	#ISC_R_UNEXPECTED
453  */
454 
455 isc_result_t
456 isc_socket_dup(isc_socket_t *sock0, isc_socket_t **socketp);
457 /*%<
458  * Duplicate an existing socket, reusing its file descriptor.
459  */
460 
461 void
462 isc_socket_cancel(isc_socket_t *sock, isc_task_t *task,
463 		  unsigned int how);
464 /*%<
465  * Cancel pending I/O of the type specified by "how".
466  *
467  * Note: if "task" is NULL, then the cancel applies to all tasks using the
468  * socket.
469  *
470  * Requires:
471  *
472  * \li	"socket" is a valid socket
473  *
474  * \li	"task" is NULL or a valid task
475  *
476  * "how" is a bitmask describing the type of cancelation to perform.
477  * The type ISC_SOCKCANCEL_ALL will cancel all pending I/O on this
478  * socket.
479  *
480  * \li ISC_SOCKCANCEL_RECV:
481  *	Cancel pending isc_socket_recv() calls.
482  *
483  * \li ISC_SOCKCANCEL_SEND:
484  *	Cancel pending isc_socket_send() and isc_socket_sendto() calls.
485  *
486  * \li ISC_SOCKCANCEL_ACCEPT:
487  *	Cancel pending isc_socket_accept() calls.
488  *
489  * \li ISC_SOCKCANCEL_CONNECT:
490  *	Cancel pending isc_socket_connect() call.
491  */
492 
493 void
494 isc_socket_shutdown(isc_socket_t *sock, unsigned int how);
495 /*%<
496  * Shutdown 'socket' according to 'how'.
497  *
498  * Requires:
499  *
500  * \li	'socket' is a valid socket.
501  *
502  * \li	'task' is NULL or is a valid task.
503  *
504  * \li	If 'how' is 'ISC_SOCKSHUT_RECV' or 'ISC_SOCKSHUT_ALL' then
505  *
506  *		The read queue must be empty.
507  *
508  *		No further read requests may be made.
509  *
510  * \li	If 'how' is 'ISC_SOCKSHUT_SEND' or 'ISC_SOCKSHUT_ALL' then
511  *
512  *		The write queue must be empty.
513  *
514  *		No further write requests may be made.
515  */
516 
517 void
518 isc_socket_attach(isc_socket_t *sock, isc_socket_t **socketp);
519 /*%<
520  * Attach *socketp to socket.
521  *
522  * Requires:
523  *
524  * \li	'socket' is a valid socket.
525  *
526  * \li	'socketp' points to a NULL socket.
527  *
528  * Ensures:
529  *
530  * \li	*socketp is attached to socket.
531  */
532 
533 void
534 isc_socket_detach(isc_socket_t **socketp);
535 /*%<
536  * Detach *socketp from its socket.
537  *
538  * Requires:
539  *
540  * \li	'socketp' points to a valid socket.
541  *
542  * \li	If '*socketp' is the last reference to the socket,
543  *	then:
544  *
545  *		There must be no pending I/O requests.
546  *
547  * Ensures:
548  *
549  * \li	*socketp is NULL.
550  *
551  * \li	If '*socketp' is the last reference to the socket,
552  *	then:
553  *
554  *		The socket will be shutdown (both reading and writing)
555  *		for all tasks.
556  *
557  *		All resources used by the socket have been freed
558  */
559 
560 isc_result_t
561 isc_socket_open(isc_socket_t *sock);
562 /*%<
563  * Open a new socket file descriptor of the given socket structure.  It simply
564  * opens a new descriptor; all of the other parameters including the socket
565  * type are inherited from the existing socket.  This function is provided to
566  * avoid overhead of destroying and creating sockets when many short-lived
567  * sockets are frequently opened and closed.  When the efficiency is not an
568  * issue, it should be safer to detach the unused socket and re-create a new
569  * one.  This optimization may not be available for some systems, in which
570  * case this function will return ISC_R_NOTIMPLEMENTED and must not be used.
571  *
572  * isc_socket_open() should not be called on sockets created by
573  * isc_socket_fdwatchcreate().
574  *
575  * Requires:
576  *
577  * \li	there must be no other reference to this socket.
578  *
579  * \li	'socket' is a valid and previously closed by isc_socket_close()
580  *
581  * \li  'sock->type' is not isc_sockettype_fdwatch
582  *
583  * Returns:
584  *	Same as isc_socket_create().
585  * \li	ISC_R_NOTIMPLEMENTED
586  */
587 
588 isc_result_t
589 isc_socket_close(isc_socket_t *sock);
590 /*%<
591  * Close a socket file descriptor of the given socket structure.  This function
592  * is provided as an alternative to destroying an unused socket when overhead
593  * destroying/re-creating sockets can be significant, and is expected to be
594  * used with isc_socket_open().  This optimization may not be available for some
595  * systems, in which case this function will return ISC_R_NOTIMPLEMENTED and
596  * must not be used.
597  *
598  * isc_socket_close() should not be called on sockets created by
599  * isc_socket_fdwatchcreate().
600  *
601  * Requires:
602  *
603  * \li	The socket must have a valid descriptor.
604  *
605  * \li	There must be no other reference to this socket.
606  *
607  * \li	There must be no pending I/O requests.
608  *
609  * \li  'sock->type' is not isc_sockettype_fdwatch
610  *
611  * Returns:
612  * \li	#ISC_R_NOTIMPLEMENTED
613  */
614 
615 isc_result_t
616 isc_socket_bind(isc_socket_t *sock, isc_sockaddr_t *addressp,
617 		unsigned int options);
618 /*%<
619  * Bind 'socket' to '*addressp'.
620  *
621  * Requires:
622  *
623  * \li	'socket' is a valid socket
624  *
625  * \li	'addressp' points to a valid isc_sockaddr.
626  *
627  * Returns:
628  *
629  * \li	ISC_R_SUCCESS
630  * \li	ISC_R_NOPERM
631  * \li	ISC_R_ADDRNOTAVAIL
632  * \li	ISC_R_ADDRINUSE
633  * \li	ISC_R_BOUND
634  * \li	ISC_R_UNEXPECTED
635  */
636 
637 isc_result_t
638 isc_socket_filter(isc_socket_t *sock, const char *filter);
639 /*%<
640  * Inform the kernel that it should perform accept filtering.
641  * If filter is NULL the current filter will be removed.:w
642  */
643 
644 isc_result_t
645 isc_socket_listen(isc_socket_t *sock, unsigned int backlog);
646 /*%<
647  * Set listen mode on the socket.  After this call, the only function that
648  * can be used (other than attach and detach) is isc_socket_accept().
649  *
650  * Notes:
651  *
652  * \li	'backlog' is as in the UNIX system call listen() and may be
653  *	ignored by non-UNIX implementations.
654  *
655  * \li	If 'backlog' is zero, a reasonable system default is used, usually
656  *	SOMAXCONN.
657  *
658  * Requires:
659  *
660  * \li	'socket' is a valid, bound TCP socket or a valid, bound UNIX socket.
661  *
662  * Returns:
663  *
664  * \li	ISC_R_SUCCESS
665  * \li	ISC_R_UNEXPECTED
666  */
667 
668 isc_result_t
669 isc_socket_accept(isc_socket_t *sock,
670 		  isc_task_t *task, isc_taskaction_t action, const void *arg);
671 /*%<
672  * Queue accept event.  When a new connection is received, the task will
673  * get an ISC_SOCKEVENT_NEWCONN event with the sender set to the listen
674  * socket.  The new socket structure is sent inside the isc_socket_newconnev_t
675  * event type, and is attached to the task 'task'.
676  *
677  * REQUIRES:
678  * \li	'socket' is a valid TCP socket that isc_socket_listen() was called
679  *	on.
680  *
681  * \li	'task' is a valid task
682  *
683  * \li	'action' is a valid action
684  *
685  * RETURNS:
686  * \li	ISC_R_SUCCESS
687  * \li	ISC_R_NOMEMORY
688  * \li	ISC_R_UNEXPECTED
689  */
690 
691 isc_result_t
692 isc_socket_connect(isc_socket_t *sock, isc_sockaddr_t *addressp,
693 		   isc_task_t *task, isc_taskaction_t action,
694 		   const void *arg);
695 /*%<
696  * Connect 'socket' to peer with address *saddr.  When the connection
697  * succeeds, or when an error occurs, a CONNECT event with action 'action'
698  * and arg 'arg' will be posted to the event queue for 'task'.
699  *
700  * Requires:
701  *
702  * \li	'socket' is a valid TCP socket
703  *
704  * \li	'addressp' points to a valid isc_sockaddr
705  *
706  * \li	'task' is a valid task
707  *
708  * \li	'action' is a valid action
709  *
710  * Returns:
711  *
712  * \li	ISC_R_SUCCESS
713  * \li	ISC_R_NOMEMORY
714  * \li	ISC_R_UNEXPECTED
715  *
716  * Posted event's result code:
717  *
718  * \li	ISC_R_SUCCESS
719  * \li	ISC_R_TIMEDOUT
720  * \li	ISC_R_CONNREFUSED
721  * \li	ISC_R_NETUNREACH
722  * \li	ISC_R_UNEXPECTED
723  */
724 
725 isc_result_t
726 isc_socket_getpeername(isc_socket_t *sock, isc_sockaddr_t *addressp);
727 /*%<
728  * Get the name of the peer connected to 'socket'.
729  *
730  * Requires:
731  *
732  * \li	'socket' is a valid TCP socket.
733  *
734  * Returns:
735  *
736  * \li	ISC_R_SUCCESS
737  * \li	ISC_R_TOOSMALL
738  * \li	ISC_R_UNEXPECTED
739  */
740 
741 isc_result_t
742 isc_socket_getsockname(isc_socket_t *sock, isc_sockaddr_t *addressp);
743 /*%<
744  * Get the name of 'socket'.
745  *
746  * Requires:
747  *
748  * \li	'socket' is a valid socket.
749  *
750  * Returns:
751  *
752  * \li	ISC_R_SUCCESS
753  * \li	ISC_R_TOOSMALL
754  * \li	ISC_R_UNEXPECTED
755  */
756 
757 /*@{*/
758 isc_result_t
759 isc_socket_recv(isc_socket_t *sock, isc_region_t *region,
760 		unsigned int minimum,
761 		isc_task_t *task, isc_taskaction_t action, const void *arg);
762 isc_result_t
763 isc_socket_recvv(isc_socket_t *sock, isc_bufferlist_t *buflist,
764 		 unsigned int minimum,
765 		 isc_task_t *task, isc_taskaction_t action, const void *arg);
766 
767 isc_result_t
768 isc_socket_recv2(isc_socket_t *sock, isc_region_t *region,
769 		 unsigned int minimum, isc_task_t *task,
770 		 isc_socketevent_t *event, unsigned int flags);
771 
772 /*!
773  * Receive from 'socket', storing the results in region.
774  *
775  * Notes:
776  *
777  *\li	Let 'length' refer to the length of 'region' or to the sum of all
778  *	available regions in the list of buffers '*buflist'.
779  *
780  *\li	If 'minimum' is non-zero and at least that many bytes are read,
781  *	the completion event will be posted to the task 'task.'  If minimum
782  *	is zero, the exact number of bytes requested in the region must
783  * 	be read for an event to be posted.  This only makes sense for TCP
784  *	connections, and is always set to 1 byte for UDP.
785  *
786  *\li	The read will complete when the desired number of bytes have been
787  *	read, if end-of-input occurs, or if an error occurs.  A read done
788  *	event with the given 'action' and 'arg' will be posted to the
789  *	event queue of 'task'.
790  *
791  *\li	The caller may not modify 'region', the buffers which are passed
792  *	into this function, or any data they refer to until the completion
793  *	event is received.
794  *
795  *\li	For isc_socket_recvv():
796  *	On successful completion, '*buflist' will be empty, and the list of
797  *	all buffers will be returned in the done event's 'bufferlist'
798  *	member.  On error return, '*buflist' will be unchanged.
799  *
800  *\li	For isc_socket_recv2():
801  *	'event' is not NULL, and the non-socket specific fields are
802  *	expected to be initialized.
803  *
804  *\li	For isc_socket_recv2():
805  *	The only defined value for 'flags' is ISC_SOCKFLAG_IMMEDIATE.  If
806  *	set and the operation completes, the return value will be
807  *	ISC_R_SUCCESS and the event will be filled in and not sent.  If the
808  *	operation does not complete, the return value will be
809  *	ISC_R_INPROGRESS and the event will be sent when the operation
810  *	completes.
811  *
812  * Requires:
813  *
814  *\li	'socket' is a valid, bound socket.
815  *
816  *\li	For isc_socket_recv():
817  *	'region' is a valid region
818  *
819  *\li	For isc_socket_recvv():
820  *	'buflist' is non-NULL, and '*buflist' contain at least one buffer.
821  *
822  *\li	'task' is a valid task
823  *
824  *\li	For isc_socket_recv() and isc_socket_recvv():
825  *	action != NULL and is a valid action
826  *
827  *\li	For isc_socket_recv2():
828  *	event != NULL
829  *
830  * Returns:
831  *
832  *\li	#ISC_R_SUCCESS
833  *\li	#ISC_R_INPROGRESS
834  *\li	#ISC_R_NOMEMORY
835  *\li	#ISC_R_UNEXPECTED
836  *
837  * Event results:
838  *
839  *\li	#ISC_R_SUCCESS
840  *\li	#ISC_R_UNEXPECTED
841  *\li	XXX needs other net-type errors
842  */
843 /*@}*/
844 
845 /*@{*/
846 isc_result_t
847 isc_socket_send(isc_socket_t *sock, isc_region_t *region,
848 		isc_task_t *task, isc_taskaction_t action, const void *arg);
849 isc_result_t
850 isc_socket_sendto(isc_socket_t *sock, isc_region_t *region,
851 		  isc_task_t *task, isc_taskaction_t action, const void *arg,
852 		  isc_sockaddr_t *address, struct in6_pktinfo *pktinfo);
853 isc_result_t
854 isc_socket_sendv(isc_socket_t *sock, isc_bufferlist_t *buflist,
855 		 isc_task_t *task, isc_taskaction_t action, const void *arg);
856 isc_result_t
857 isc_socket_sendtov(isc_socket_t *sock, isc_bufferlist_t *buflist,
858 		   isc_task_t *task, isc_taskaction_t action, const void *arg,
859 		   isc_sockaddr_t *address, struct in6_pktinfo *pktinfo);
860 isc_result_t
861 isc_socket_sendto2(isc_socket_t *sock, isc_region_t *region,
862 		   isc_task_t *task,
863 		   isc_sockaddr_t *address, struct in6_pktinfo *pktinfo,
864 		   isc_socketevent_t *event, unsigned int flags);
865 
866 /*!
867  * Send the contents of 'region' to the socket's peer.
868  *
869  * Notes:
870  *
871  *\li	Shutting down the requestor's task *may* result in any
872  *	still pending writes being dropped or completed, depending on the
873  *	underlying OS implementation.
874  *
875  *\li	If 'action' is NULL, then no completion event will be posted.
876  *
877  *\li	The caller may not modify 'region', the buffers which are passed
878  *	into this function, or any data they refer to until the completion
879  *	event is received.
880  *
881  *\li	For isc_socket_sendv() and isc_socket_sendtov():
882  *	On successful completion, '*buflist' will be empty, and the list of
883  *	all buffers will be returned in the done event's 'bufferlist'
884  *	member.  On error return, '*buflist' will be unchanged.
885  *
886  *\li	For isc_socket_sendto2():
887  *	'event' is not NULL, and the non-socket specific fields are
888  *	expected to be initialized.
889  *
890  *\li	For isc_socket_sendto2():
891  *	The only defined values for 'flags' are ISC_SOCKFLAG_IMMEDIATE
892  *	and ISC_SOCKFLAG_NORETRY.
893  *
894  *\li	If ISC_SOCKFLAG_IMMEDIATE is set and the operation completes, the
895  *	return value will be ISC_R_SUCCESS and the event will be filled
896  *	in and not sent.  If the operation does not complete, the return
897  *	value will be ISC_R_INPROGRESS and the event will be sent when
898  *	the operation completes.
899  *
900  *\li	ISC_SOCKFLAG_NORETRY can only be set for UDP sockets.  If set
901  *	and the send operation fails due to a transient error, the send
902  *	will not be retried and the error will be indicated in the event.
903  *	Using this option along with ISC_SOCKFLAG_IMMEDIATE allows the caller
904  *	to specify a region that is allocated on the stack.
905  *
906  * Requires:
907  *
908  *\li	'socket' is a valid, bound socket.
909  *
910  *\li	For isc_socket_send():
911  *	'region' is a valid region
912  *
913  *\li	For isc_socket_sendv() and isc_socket_sendtov():
914  *	'buflist' is non-NULL, and '*buflist' contain at least one buffer.
915  *
916  *\li	'task' is a valid task
917  *
918  *\li	For isc_socket_sendv(), isc_socket_sendtov(), isc_socket_send(), and
919  *	isc_socket_sendto():
920  *	action == NULL or is a valid action
921  *
922  *\li	For isc_socket_sendto2():
923  *	event != NULL
924  *
925  * Returns:
926  *
927  *\li	#ISC_R_SUCCESS
928  *\li	#ISC_R_INPROGRESS
929  *\li	#ISC_R_NOMEMORY
930  *\li	#ISC_R_UNEXPECTED
931  *
932  * Event results:
933  *
934  *\li	#ISC_R_SUCCESS
935  *\li	#ISC_R_UNEXPECTED
936  *\li	XXX needs other net-type errors
937  */
938 /*@}*/
939 
940 isc_result_t
941 isc_socketmgr_createinctx(isc_mem_t *mctx, isc_appctx_t *actx,
942 			  isc_socketmgr_t **managerp);
943 
944 isc_result_t
945 isc_socketmgr_create(isc_mem_t *mctx, isc_socketmgr_t **managerp);
946 
947 isc_result_t
948 isc_socketmgr_create2(isc_mem_t *mctx, isc_socketmgr_t **managerp,
949 		      unsigned int maxsocks);
950 /*%<
951  * Create a socket manager.  If "maxsocks" is non-zero, it specifies the
952  * maximum number of sockets that the created manager should handle.
953  * isc_socketmgr_create() is equivalent of isc_socketmgr_create2() with
954  * "maxsocks" being zero.
955  * isc_socketmgr_createinctx() also associates the new manager with the
956  * specified application context.
957  *
958  * Notes:
959  *
960  *\li	All memory will be allocated in memory context 'mctx'.
961  *
962  * Requires:
963  *
964  *\li	'mctx' is a valid memory context.
965  *
966  *\li	'managerp' points to a NULL isc_socketmgr_t.
967  *
968  *\li	'actx' is a valid application context (for createinctx()).
969  *
970  * Ensures:
971  *
972  *\li	'*managerp' is a valid isc_socketmgr_t.
973  *
974  * Returns:
975  *
976  *\li	#ISC_R_SUCCESS
977  *\li	#ISC_R_NOMEMORY
978  *\li	#ISC_R_UNEXPECTED
979  *\li	#ISC_R_NOTIMPLEMENTED
980  */
981 
982 isc_result_t
983 isc_socketmgr_getmaxsockets(isc_socketmgr_t *manager, unsigned int *nsockp);
984 /*%<
985  * Returns in "*nsockp" the maximum number of sockets this manager may open.
986  *
987  * Requires:
988  *
989  *\li	'*manager' is a valid isc_socketmgr_t.
990  *\li	'nsockp' is not NULL.
991  *
992  * Returns:
993  *
994  *\li	#ISC_R_SUCCESS
995  *\li	#ISC_R_NOTIMPLEMENTED
996  */
997 
998 void
999 isc_socketmgr_setstats(isc_socketmgr_t *manager, isc_stats_t *stats);
1000 /*%<
1001  * Set a general socket statistics counter set 'stats' for 'manager'.
1002  *
1003  * Requires:
1004  * \li	'manager' is valid, hasn't opened any socket, and doesn't have
1005  *	stats already set.
1006  *
1007  *\li	stats is a valid statistics supporting socket statistics counters
1008  *	(see above).
1009  */
1010 
1011 void
1012 isc_socketmgr_destroy(isc_socketmgr_t **managerp);
1013 /*%<
1014  * Destroy a socket manager.
1015  *
1016  * Notes:
1017  *
1018  *\li	This routine blocks until there are no sockets left in the manager,
1019  *	so if the caller holds any socket references using the manager, it
1020  *	must detach them before calling isc_socketmgr_destroy() or it will
1021  *	block forever.
1022  *
1023  * Requires:
1024  *
1025  *\li	'*managerp' is a valid isc_socketmgr_t.
1026  *
1027  *\li	All sockets managed by this manager are fully detached.
1028  *
1029  * Ensures:
1030  *
1031  *\li	*managerp == NULL
1032  *
1033  *\li	All resources used by the manager have been freed.
1034  */
1035 
1036 isc_sockettype_t
1037 isc_socket_gettype(isc_socket_t *sock);
1038 /*%<
1039  * Returns the socket type for "sock."
1040  *
1041  * Requires:
1042  *
1043  *\li	"sock" is a valid socket.
1044  */
1045 
1046 /*@{*/
1047 isc_boolean_t
1048 isc_socket_isbound(isc_socket_t *sock);
1049 
1050 void
1051 isc_socket_ipv6only(isc_socket_t *sock, isc_boolean_t yes);
1052 /*%<
1053  * If the socket is an IPv6 socket set/clear the IPV6_IPV6ONLY socket
1054  * option if the host OS supports this option.
1055  *
1056  * Requires:
1057  *\li	'sock' is a valid socket.
1058  */
1059 /*@}*/
1060 
1061 void
1062 isc_socket_cleanunix(isc_sockaddr_t *addr, isc_boolean_t active);
1063 
1064 /*%<
1065  * Cleanup UNIX domain sockets in the file-system.  If 'active' is true
1066  * then just unlink the socket.  If 'active' is false try to determine
1067  * if there is a listener of the socket or not.  If no listener is found
1068  * then unlink socket.
1069  *
1070  * Prior to unlinking the path is tested to see if it a socket.
1071  *
1072  * Note: there are a number of race conditions which cannot be avoided
1073  *       both in the filesystem and any application using UNIX domain
1074  *	 sockets (e.g. socket is tested between bind() and listen(),
1075  *	 the socket is deleted and replaced in the file-system between
1076  *	 stat() and unlink()).
1077  */
1078 
1079 isc_result_t
1080 isc_socket_permunix(isc_sockaddr_t *sockaddr, isc_uint32_t perm,
1081 		    isc_uint32_t owner, isc_uint32_t group);
1082 /*%<
1083  * Set ownership and file permissions on the UNIX domain socket.
1084  *
1085  * Note: On Solaris and SunOS this secures the directory containing
1086  *       the socket as Solaris and SunOS do not honour the filesystem
1087  *	 permissions on the socket.
1088  *
1089  * Requires:
1090  * \li	'sockaddr' to be a valid UNIX domain sockaddr.
1091  *
1092  * Returns:
1093  * \li	#ISC_R_SUCCESS
1094  * \li	#ISC_R_FAILURE
1095  */
1096 
1097 void isc_socket_setname(isc_socket_t *sock, const char *name, void *tag);
1098 /*%<
1099  * Set the name and optional tag for a socket.  This allows tracking of the
1100  * owner or purpose for this socket, and is useful for tracing and statistics
1101  * reporting.
1102  */
1103 
1104 const char *isc_socket_getname(isc_socket_t *sock);
1105 /*%<
1106  * Get the name associated with a socket, if any.
1107  */
1108 
1109 void *isc_socket_gettag(isc_socket_t *sock);
1110 /*%<
1111  * Get the tag associated with a socket, if any.
1112  */
1113 
1114 int isc_socket_getfd(isc_socket_t *sock);
1115 /*%<
1116  * Get the file descriptor associated with a socket
1117  */
1118 
1119 void
1120 isc__socketmgr_setreserved(isc_socketmgr_t *mgr, isc_uint32_t);
1121 /*%<
1122  * Temporary.  For use by named only.
1123  */
1124 
1125 void
1126 isc__socketmgr_maxudp(isc_socketmgr_t *mgr, int maxudp);
1127 /*%<
1128  * Test interface. Drop UDP packet > 'maxudp'.
1129  */
1130 
1131 #ifdef HAVE_LIBXML2
1132 
1133 void
1134 isc_socketmgr_renderxml(isc_socketmgr_t *mgr, xmlTextWriterPtr writer);
1135 /*%<
1136  * Render internal statistics and other state into the XML document.
1137  */
1138 
1139 #endif /* HAVE_LIBXML2 */
1140 
1141 #ifdef USE_SOCKETIMPREGISTER
1142 /*%<
1143  * See isc_socketmgr_create() above.
1144  */
1145 typedef isc_result_t
1146 (*isc_socketmgrcreatefunc_t)(isc_mem_t *mctx, isc_socketmgr_t **managerp);
1147 
1148 isc_result_t
1149 isc_socket_register(isc_socketmgrcreatefunc_t createfunc);
1150 /*%<
1151  * Register a new socket I/O implementation and add it to the list of
1152  * supported implementations.  This function must be called when a different
1153  * event library is used than the one contained in the ISC library.
1154  */
1155 
1156 isc_result_t
1157 isc__socket_register(void);
1158 /*%<
1159  * A short cut function that specifies the socket I/O module in the ISC
1160  * library for isc_socket_register().  An application that uses the ISC library
1161  * usually do not have to care about this function: it would call
1162  * isc_lib_register(), which internally calls this function.
1163  */
1164 #endif /* USE_SOCKETIMPREGISTER */
1165 
1166 ISC_LANG_ENDDECLS
1167 
1168 #endif /* ISC_SOCKET_H */
1169