aboutsummaryrefslogtreecommitdiff
path: root/src/include/gnunet_network_lib.h
blob: 6c02f3577193f5ef54a2edef33b1f7317fe9f04d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
/*
     This file is part of GNUnet.
     Copyright (C) 2009-2013 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Affero General Public License for more details.
    
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
*/

/**
 * @author Nils Durner
 *
 * @file
 * Basic low-level networking interface
 *
 * @defgroup network  Network library
 * Basic low-level networking interface
 * @{
 */
#ifndef GNUNET_NETWORK_LIB_H
#define GNUNET_NETWORK_LIB_H

#ifdef __cplusplus
extern "C"
{
#if 0                           /* keep Emacsens' auto-indent happy */
}
#endif
#endif


/**
 * @brief handle to a socket
 */
struct GNUNET_NETWORK_Handle;


/**
 * @brief collection of IO descriptors
 */
struct GNUNET_NETWORK_FDSet
{

  /**
   * Maximum number of any socket descriptor in the set (plus one)
   */
  int nsds;

  /**
   * Bitset with the descriptors.
   */
  fd_set sds;

#ifdef WINDOWS
  /**
   * Array of file handles (from pipes) that are also in
   * the FDSet.  Needed as those cannot go into @e sds
   * on W32.
   */
  const struct GNUNET_DISK_FileHandle **handles;

  /**
   * Size of the @e handles array
   */
  unsigned int handles_size;

  /**
   * Number of @e handles slots in use. Always
   * smaller than @e handles_size.
   */
  unsigned int handles_pos;

#endif

};

#include "gnunet_disk_lib.h"
#include "gnunet_time_lib.h"

/**
 * Test if the given protocol family is supported by this system.
 *
 * @param pf protocol family to test (PF_INET, PF_INET6, PF_UNIX)
 * @return #GNUNET_OK if the PF is supported
 */
int
GNUNET_NETWORK_test_pf (int pf);


/**
 * Given a unixpath that is too long (larger than UNIX_PATH_MAX),
 * shorten it to an acceptable length while keeping it unique
 * and making sure it remains a valid filename (if possible).
 *
 * @param unixpath long path, will be freed (or same pointer returned
 *        with moved 0-termination).
 * @return shortened unixpath, NULL on error
 */
char *
GNUNET_NETWORK_shorten_unixpath (char *unixpath);


#ifndef WINDOWS
/**
 * If services crash, they can leave a unix domain socket file on the
 * disk. This needs to be manually removed, because otherwise both
 * bind() and connect() for the respective address will fail.  In this
 * function, we test if such a left-over file exists, and if so,
 * remove it (unless there is a listening service at the address).
 *
 * @param un unix domain socket address to check
 */
void
GNUNET_NETWORK_unix_precheck (const struct sockaddr_un *un);
#endif


/**
 * Accept a new connection on a socket.  Configure it for non-blocking
 * IO and mark it as non-inheritable to child processes (set the
 * close-on-exec flag).
 *
 * @param desc bound socket
 * @param address address of the connecting peer, may be NULL
 * @param address_len length of address
 * @return client socket
 */
struct GNUNET_NETWORK_Handle *
GNUNET_NETWORK_socket_accept (const struct GNUNET_NETWORK_Handle *desc,
                              struct sockaddr *address,
                              socklen_t *address_len);


/**
 * Box a native socket (and check that it is a socket).
 *
 * @param fd socket to box
 * @return NULL on error (including not supported on target platform)
 */
struct GNUNET_NETWORK_Handle *
GNUNET_NETWORK_socket_box_native (SOCKTYPE fd);


/**
 * Set if a socket should use blocking or non-blocking IO.
 *
 * @param fd socket
 * @param doBlock blocking mode
 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
 */
int
GNUNET_NETWORK_socket_set_blocking (struct GNUNET_NETWORK_Handle *fd,
				    int doBlock);


/**
 * Bind a socket to a particular address.
 *
 * @param desc socket to bind
 * @param address address to be bound
 * @param address_len length of @a address
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_bind (struct GNUNET_NETWORK_Handle *desc,
                            const struct sockaddr *address,
                            socklen_t address_len);

/**
 * Close a socket.
 *
 * @param desc socket to close
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_close (struct GNUNET_NETWORK_Handle *desc);


/**
 * Only free memory of a socket, keep the file descriptor untouched.
 *
 * @param desc socket
 */
void
GNUNET_NETWORK_socket_free_memory_only_ (struct GNUNET_NETWORK_Handle *desc);


/**
 * Connect a socket to some remote address.
 *
 * @param desc socket to connect
 * @param address peer address
 * @param address_len of @a address
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_connect (const struct GNUNET_NETWORK_Handle *desc,
                               const struct sockaddr *address,
                               socklen_t address_len);


/**
 * Get socket options
 *
 * @param desc socket to inspect
 * @param level protocol level of the option
 * @param optname identifier of the option
 * @param optval options
 * @param optlen length of optval
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_getsockopt (const struct GNUNET_NETWORK_Handle *desc,
                                  int level,
                                  int optname,
                                  void *optval,
                                  socklen_t *optlen);


/**
 * Listen on a socket
 *
 * @param desc socket to start listening on
 * @param backlog length of the listen queue
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_listen (const struct GNUNET_NETWORK_Handle *desc,
                              int backlog);


/**
 * How much data is available to be read on this descriptor?
 *
 * @param desc socket
 * @returns #GNUNET_SYSERR if no data is available, or on error!
 */
ssize_t
GNUNET_NETWORK_socket_recvfrom_amount (const struct GNUNET_NETWORK_Handle *desc);


/**
 * Read data from a socket (always non-blocking).
 *
 * @param desc socket
 * @param buffer buffer
 * @param length length of buffer
 * @param src_addr either the source to recv from, or all zeroes
 *        to be filled in by recvfrom
 * @param addrlen length of the addr
 */
ssize_t
GNUNET_NETWORK_socket_recvfrom (const struct GNUNET_NETWORK_Handle *desc,
                                void *buffer,
                                size_t length,
                                struct sockaddr *src_addr,
                                socklen_t *addrlen);


/**
 * Read data from a connected socket (always non-blocking).
 *
 * @param desc socket
 * @param buffer buffer
 * @param length length of buffer
 * @return number of bytes read
 */
ssize_t
GNUNET_NETWORK_socket_recv (const struct GNUNET_NETWORK_Handle *desc,
                            void *buffer,
                            size_t length);


/**
 * Check if sockets meet certain conditions.
 *
 * @param rfds set of sockets to be checked for readability
 * @param wfds set of sockets to be checked for writability
 * @param efds set of sockets to be checked for exceptions
 * @param timeout relative value when to return
 * @return number of selected sockets, #GNUNET_SYSERR on error
 */
int
GNUNET_NETWORK_socket_select (struct GNUNET_NETWORK_FDSet *rfds,
                              struct GNUNET_NETWORK_FDSet *wfds,
                              struct GNUNET_NETWORK_FDSet *efds,
                              struct GNUNET_TIME_Relative timeout);


/**
 * Send data (always non-blocking).
 *
 * @param desc socket
 * @param buffer data to send
 * @param length size of the buffer
 * @return number of bytes sent, #GNUNET_SYSERR on error
 */
ssize_t
GNUNET_NETWORK_socket_send (const struct GNUNET_NETWORK_Handle *desc,
                            const void *buffer,
                            size_t length);


/**
 * Send data to a particular destination (always non-blocking).
 * This function only works for UDP sockets.
 *
 * @param desc socket
 * @param message data to send
 * @param length size of the data in @a message
 * @param dest_addr destination address
 * @param dest_len length of @a dest_addr
 * @return number of bytes sent, #GNUNET_SYSERR on error
 */
ssize_t
GNUNET_NETWORK_socket_sendto (const struct GNUNET_NETWORK_Handle *desc,
                              const void *message,
                              size_t length,
                              const struct sockaddr *dest_addr,
                              socklen_t dest_len);


/**
 * Set socket option
 *
 * @param fd socket
 * @param level protocol level of the option
 * @param option_name option identifier
 * @param option_value value to set
 * @param option_len size of @a option_value
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_setsockopt (struct GNUNET_NETWORK_Handle *fd,
                                  int level,
                                  int option_name,
                                  const void *option_value,
                                  socklen_t option_len);


/**
 * Shut down socket operations
 *
 * @param desc socket
 * @param how type of shutdown
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_shutdown (struct GNUNET_NETWORK_Handle *desc,
                                int how);


/**
 * Disable the "CORK" feature for communication with the given socket,
 * forcing the OS to immediately flush the buffer on transmission
 * instead of potentially buffering multiple messages.  Essentially
 * reduces the OS send buffers to zero.
 *
 * @param desc socket
 * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 */
int
GNUNET_NETWORK_socket_disable_corking (struct GNUNET_NETWORK_Handle *desc);


/**
 * Create a new socket.   Configure it for non-blocking IO and
 * mark it as non-inheritable to child processes (set the
 * close-on-exec flag).
 *
 * @param domain domain of the socket
 * @param type socket type
 * @param protocol network protocol
 * @return new socket, NULL on error
 */
struct GNUNET_NETWORK_Handle *
GNUNET_NETWORK_socket_create (int domain,
                              int type,
                              int protocol);


/**
 * Reset FD set (clears all file descriptors).
 *
 * @param fds fd set to clear
 */
void
GNUNET_NETWORK_fdset_zero (struct GNUNET_NETWORK_FDSet *fds);


/**
 * Add a socket to the FD set
 *
 * @param fds fd set
 * @param desc socket to add
 */
void
GNUNET_NETWORK_fdset_set (struct GNUNET_NETWORK_FDSet *fds,
                          const struct GNUNET_NETWORK_Handle *desc);


#if WINDOWS
/**
 * Add a W32 file handle to the fd set
 *
 * @param fds fd set
 * @param h the file handle to add
 */
void
GNUNET_NETWORK_fdset_handle_set_native_w32_handle (struct GNUNET_NETWORK_FDSet *fds,
                                                   HANDLE h);
#endif


/**
 * Check whether a socket is part of the fd set
 *
 * @param fds fd set
 * @param desc socket
 * @return #GNUNET_YES if the socket is in the set
 */
int
GNUNET_NETWORK_fdset_isset (const struct GNUNET_NETWORK_FDSet *fds,
                            const struct GNUNET_NETWORK_Handle *desc);


/**
 * Add one fd set to another (computes the union).
 *
 * @param dst the fd set to add to
 * @param src the fd set to add from
 */
void
GNUNET_NETWORK_fdset_add (struct GNUNET_NETWORK_FDSet *dst,
                          const struct GNUNET_NETWORK_FDSet *src);


/**
 * Copy one fd set to another
 *
 * @param to destination
 * @param from source
 */
void
GNUNET_NETWORK_fdset_copy (struct GNUNET_NETWORK_FDSet *to,
                           const struct GNUNET_NETWORK_FDSet *from);


/**
 * Return file descriptor for this network handle
 *
 * @param desc wrapper to process
 * @return POSIX file descriptor
 */
int
GNUNET_NETWORK_get_fd (const struct GNUNET_NETWORK_Handle *desc);


/**
 * Return the sockaddr for this network handle
 *
 * @param desc wrapper to process
 * @return POSIX file descriptor
 */
struct sockaddr*
GNUNET_NETWORK_get_addr (const struct GNUNET_NETWORK_Handle *desc);


/**
 * Return sockaddr length for this network handle
 *
 * @param desc wrapper to process
 * @return socklen_t for sockaddr
 */
socklen_t
GNUNET_NETWORK_get_addrlen (const struct GNUNET_NETWORK_Handle *desc);


/**
 * Copy a native fd set into the GNUnet representation.
 *
 * @param to destination
 * @param from native source set
 * @param nfds the biggest socket number in from + 1
 */
void
GNUNET_NETWORK_fdset_copy_native (struct GNUNET_NETWORK_FDSet *to,
                                  const fd_set *from,
                                  int nfds);


/**
 * Set a native fd in a set
 *
 * @param to destination
 * @param nfd native FD to set
 */
void
GNUNET_NETWORK_fdset_set_native (struct GNUNET_NETWORK_FDSet *to,
                                 int nfd);


/**
 * Test native fd in a set
 *
 * @param to set to test, NULL for empty set
 * @param nfd native FD to test, -1 for none
 * @return #GNUNET_YES if to contains nfd
 */
int
GNUNET_NETWORK_fdset_test_native (const struct GNUNET_NETWORK_FDSet *to,
                                  int nfd);


/**
 * Add a file handle to the fd set
 *
 * @param fds fd set
 * @param h the file handle to add
 */
void
GNUNET_NETWORK_fdset_handle_set (struct GNUNET_NETWORK_FDSet *fds,
                                 const struct GNUNET_DISK_FileHandle *h);


/**
 * Add a file handle to the fd set
 * On W32: ensure that the handle is first in the array.
 *
 * @param fds fd set
 * @param h the file handle to add
 */
void
GNUNET_NETWORK_fdset_handle_set_first (struct GNUNET_NETWORK_FDSet *fds,
                                       const struct GNUNET_DISK_FileHandle *h);


/**
 * Check if a file handle is part of an fd set
 *
 * @param fds fd set
 * @param h file handle
 * @return #GNUNET_YES if the file handle is part of the set
 */
int
GNUNET_NETWORK_fdset_handle_isset (const struct GNUNET_NETWORK_FDSet *fds,
                                   const struct GNUNET_DISK_FileHandle *h);


/**
 * Checks if two fd sets overlap
 *
 * @param fds1 first fd set
 * @param fds2 second fd set
 * @return #GNUNET_YES if they do overlap, #GNUNET_NO otherwise
 */
int
GNUNET_NETWORK_fdset_overlap (const struct GNUNET_NETWORK_FDSet *fds1,
                              const struct GNUNET_NETWORK_FDSet *fds2);


/**
 * Creates an fd set
 *
 * @return a new fd set
 */
struct GNUNET_NETWORK_FDSet *
GNUNET_NETWORK_fdset_create (void);


/**
 * Releases the associated memory of an fd set
 *
 * @param fds fd set
 */
void
GNUNET_NETWORK_fdset_destroy (struct GNUNET_NETWORK_FDSet *fds);


/**
 * Test if the given @a port is available.
 *
 * @param ipproto transport protocol to test (i.e. IPPROTO_TCP)
 * @param port port number to test
 * @return #GNUNET_OK if the port is available, #GNUNET_NO if not
 */
int
GNUNET_NETWORK_test_port_free (int ipproto,
			       uint16_t port);


#if 0                           /* keep Emacsens' auto-indent happy */
{
#endif
#ifdef __cplusplus
}
#endif

#endif /* GNUNET_NETWORK_LIB_H */

/** @} */  /* end of group */