summaryrefslogtreecommitdiff
path: root/src/include/gnunet_messenger_service.h
blob: 8f5315c30b3166a3d9336e95eb2ee21285481bdc (plain)
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
/*
   This file is part of GNUnet.
   Copyright (C) 2020 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 Tobias Frisch
 *
 * @file
 * MESSENGER service; manages decentralized chat groups
 *
 * @defgroup messenger  MESSENGER service
 * Instant messaging based on the CADET subsystem
 *
 * @{
 */

#ifndef GNUNET_MESSENGER_SERVICE_H
#define GNUNET_MESSENGER_SERVICE_H

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

#include "platform.h"
#include "gnunet_configuration_lib.h"
#include "gnunet_crypto_lib.h"
#include "gnunet_identity_service.h"
#include "gnunet_mq_lib.h"
#include "gnunet_protocols.h"
#include "gnunet_scheduler_lib.h"
#include "gnunet_time_lib.h"

#define GNUNET_MESSENGER_SERVICE_NAME "messenger"

/**
 * Opaque handle to the messenger
 */
struct GNUNET_MESSENGER_Handle;

/**
 * Opaque handle to a room
 */
struct GNUNET_MESSENGER_Room;

/**
 * Opaque handle to a contact
 */
struct GNUNET_MESSENGER_Contact;

/**
 * Enum for the different supported kinds of messages
 */
enum GNUNET_MESSENGER_MessageKind
{
  GNUNET_MESSENGER_KIND_INFO = 1,

  GNUNET_MESSENGER_KIND_JOIN = 2,
  GNUNET_MESSENGER_KIND_LEAVE = 3,

  GNUNET_MESSENGER_KIND_NAME = 4,
  GNUNET_MESSENGER_KIND_KEY = 5,
  GNUNET_MESSENGER_KIND_PEER = 6,
  GNUNET_MESSENGER_KIND_ID = 7,

  GNUNET_MESSENGER_KIND_MISS = 8,
  GNUNET_MESSENGER_KIND_MERGE = 9,
  GNUNET_MESSENGER_KIND_REQUEST = 10,

  GNUNET_MESSENGER_KIND_INVITE = 11,
  GNUNET_MESSENGER_KIND_TEXT = 12,
  GNUNET_MESSENGER_KIND_FILE = 13,

  GNUNET_MESSENGER_KIND_PRIVATE = 14,

  GNUNET_MESSENGER_KIND_UNKNOWN = 0
}__attribute__((__packed__));

/**
 * Get the name of a message <i>kind</i>.
 *
 * @param kind Kind of a message
 * @return Name of that kind
 */
const char*
GNUNET_MESSENGER_name_of_kind (enum GNUNET_MESSENGER_MessageKind kind);

struct GNUNET_MESSENGER_MessageHeader
{
  struct GNUNET_IDENTITY_Signature signature;

  struct GNUNET_TIME_AbsoluteNBO timestamp;

  struct GNUNET_ShortHashCode sender_id;
  struct GNUNET_HashCode previous;

  enum GNUNET_MESSENGER_MessageKind kind;
};

struct GNUNET_MESSENGER_MessageInfo
{
  struct GNUNET_IDENTITY_PublicKey host_key;
  struct GNUNET_ShortHashCode unique_id;
};

struct GNUNET_MESSENGER_MessageJoin
{
  struct GNUNET_IDENTITY_PublicKey key;
};

struct GNUNET_MESSENGER_MessageLeave
{
};

struct GNUNET_MESSENGER_MessageName
{
  char *name;
};

struct GNUNET_MESSENGER_MessageKey
{
  struct GNUNET_IDENTITY_PublicKey key;
};

struct GNUNET_MESSENGER_MessagePeer
{
  struct GNUNET_PeerIdentity peer;
};

struct GNUNET_MESSENGER_MessageId
{
  struct GNUNET_ShortHashCode id;
};

struct GNUNET_MESSENGER_MessageMiss
{
  struct GNUNET_PeerIdentity peer;
};

struct GNUNET_MESSENGER_MessageMerge
{
  struct GNUNET_HashCode previous;
};

struct GNUNET_MESSENGER_MessageRequest
{
  struct GNUNET_HashCode hash;
};

struct GNUNET_MESSENGER_MessageInvite
{
  struct GNUNET_PeerIdentity door;
  struct GNUNET_HashCode key;
};

struct GNUNET_MESSENGER_MessageText
{
  char *text;
};

struct GNUNET_MESSENGER_MessageFile
{
  struct GNUNET_CRYPTO_SymmetricSessionKey key;
  struct GNUNET_HashCode hash;
  char name[NAME_MAX];
  char *uri;
};

struct GNUNET_MESSENGER_MessagePrivate
{
  struct GNUNET_CRYPTO_EcdhePublicKey key;

  uint16_t length;
  char *data;
};

struct GNUNET_MESSENGER_MessageBody
{
  union
  {
    struct GNUNET_MESSENGER_MessageInfo info;

    struct GNUNET_MESSENGER_MessageJoin join;
    struct GNUNET_MESSENGER_MessageLeave leave;

    struct GNUNET_MESSENGER_MessageName name;
    struct GNUNET_MESSENGER_MessageKey key;
    struct GNUNET_MESSENGER_MessagePeer peer;
    struct GNUNET_MESSENGER_MessageId id;

    struct GNUNET_MESSENGER_MessageMiss miss;
    struct GNUNET_MESSENGER_MessageMerge merge;
    struct GNUNET_MESSENGER_MessageRequest request;

    struct GNUNET_MESSENGER_MessageInvite invite;
    struct GNUNET_MESSENGER_MessageText text;
    struct GNUNET_MESSENGER_MessageFile file;

    struct GNUNET_MESSENGER_MessagePrivate private;
  };
};

/**
 * Struct to a message
 */
struct GNUNET_MESSENGER_Message
{
  struct GNUNET_MESSENGER_MessageHeader header;
  struct GNUNET_MESSENGER_MessageBody body;
};

/**
 * Method called whenever the EGO of a <i>handle</i> changes or if the first connection fails
 * to load a valid EGO and the anonymous keypair will be used instead.
 *
 * @param cls Closure from <i>GNUNET_MESSENGER_connect</i>
 * @param handle Messenger handle
 */
typedef void
(*GNUNET_MESSENGER_IdentityCallback) (void *cls, struct GNUNET_MESSENGER_Handle *handle);

/**
 * Method called whenever a message is sent or received from a <i>room</i>.
 *
 * @param cls Closure from <i>GNUNET_MESSENGER_connect</i>
 * @param room Room handle
 * @param message Newly received or sent message
 * @param hash Hash identifying the message
 */
typedef void
(*GNUNET_MESSENGER_MessageCallback) (void *cls, const struct GNUNET_MESSENGER_Room *room,
                                     const struct GNUNET_MESSENGER_Message *message, const struct GNUNET_HashCode *hash);

/**
 * Set up a handle for the messenger related functions and connects to all necessary services. It will look up the ego
 * key identified by its <i>name</i> and use it for signing all messages from the handle.
 *
 * @param cfg Configuration to use
 * @param name Name to look up an ego or NULL to stay anonymous
 * @param identity_callback Function called when the EGO of the handle changes
 * @param identity_cls Closure for the <i>identity_callback</i> handler
 * @param msg_callback Function called when a new message is sent or received
 * @param msg_cls Closure for the <i>msg_callback</i> handler
 * @return Messenger handle to use, NULL on error
 */
struct GNUNET_MESSENGER_Handle*
GNUNET_MESSENGER_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, const char *name,
                          GNUNET_MESSENGER_IdentityCallback identity_callback, void *identity_cls,
                          GNUNET_MESSENGER_MessageCallback msg_callback, void *msg_cls);

/**
 * Update a handle of the messenger to use a different ego key and replace the old one with a newly generated one. All
 * participated rooms get informed about the key renewal. The handle requires a set name for this function to work and
 * it needs to be unused by other egos.
 *
 * Keep in mind that this will fully delete the old ego key (if any is used) even if any other service wants to use it
 * as default.
 *
 * @param handle Messenger handle to use
 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
 */
int
GNUNET_MESSENGER_update (struct GNUNET_MESSENGER_Handle *handle);

/**
 * Disconnect all of the messengers used services and clears up its used memory.
 *
 * @param handle Messenger handle to use
 */
void
GNUNET_MESSENGER_disconnect (struct GNUNET_MESSENGER_Handle *handle);

/**
 * Get the name (if specified, otherwise NULL) used by the messenger.
 *
 * @param handle Messenger handle to use
 * @return Name used by the messenger or NULL
 */
const char*
GNUNET_MESSENGER_get_name (const struct GNUNET_MESSENGER_Handle *handle);

/**
 * Set the name for the messenger. This will rename the currently used ego and move all stored files related to the current
 * name to its new directory. If anything fails during this process the function returns GNUNET_NO and the name for
 * the messenger won't change as specified.
 *
 * @param handle Messenger handle to use
 * @param name Name for the messenger to change to
 * @return GNUNET_YES on success, GNUNET_NO on failure and GNUNET_SYSERR if <i>handle</i> is NULL
 */
int
GNUNET_MESSENGER_set_name (struct GNUNET_MESSENGER_Handle *handle, const char *name);

/**
 * Get the public key used by the messenger.
 *
 * @param handle Messenger handle to use
 * @return Used ego's public key
 */
const struct GNUNET_IDENTITY_PublicKey*
GNUNET_MESSENGER_get_key (const struct GNUNET_MESSENGER_Handle *handle);

/**
 * Open a room to send and receive messages. The room will use the specified <i>key</i> as port for the underlying cadet
 * service. Opening a room results in opening the port for incoming connections as possible <b>door</b>.
 *
 * Notice that there can only be one room related to a specific <i>key</i>. So trying to open two rooms with the same
 * <i>key</i> will result in opening the room once but returning the handle both times because the room stays open.
 *
 * You can also open a room after entering it through a <b>door</b> using <i>GNUNET_MESSENGER_entry_room(...)</i>. This
 * will notify all entered <b>doors</b> to list you as new <b>door</b>.
 *
 * ( All <b>doors</b> form a ring structured network to shorten the latency sending and receiving messages. )
 *
 * @param handle Messenger handle to use
 * @param key Hash identifying the port
 * @return Room handle, NULL on error
 */
struct GNUNET_MESSENGER_Room*
GNUNET_MESSENGER_open_room (struct GNUNET_MESSENGER_Handle *handle, const struct GNUNET_HashCode *key);

/**
 * Enter a room to send and receive messages through a <b>door</b> opened using <i>GNUNET_MESSENGER_open_room(...)</i>.
 *
 * Notice that there can only be one room related to a specific <i>key</i>. So trying to enter two rooms with the same
 * <i>key</i> will result in entering the room once but returning the handle both times because the room stays entered.
 * You can however enter a room through multiple <b>doors</b> in parallel which results in connecting both ends. But
 * entering the room through the same <b>door</b> won't have any effect after the first time.
 *
 * You can also enter a room through a <b>door</b> after opening it using <i>GNUNET_MESSENGER_open_room(...)</i>. But the
 * <b>door</b> may not be your own peer identity.
 *
 * ( All <b>doors</b> form a ring structured network to shorten the latency sending and receiving messages. )
 *
 * @param handle Messenger handle to use
 * @param door Peer identity of an open <b>door</b>
 * @param key Hash identifying the port
 * @return Room handle, NULL on error
 */
struct GNUNET_MESSENGER_Room*
GNUNET_MESSENGER_entry_room (struct GNUNET_MESSENGER_Handle *handle, const struct GNUNET_PeerIdentity *door,
                             const struct GNUNET_HashCode *key);

/**
 * Close a room which was entered, opened or both in various order and variety. Closing a room will destroy all connections
 * from your peer to another and the other way around.
 *
 * ( After a member closes a <b>door</b>, all members entered through that specific <b>door</b> have to use another one
 * or open the room on their own. )
 *
 * @param room Room handle
 */
void
GNUNET_MESSENGER_close_room (struct GNUNET_MESSENGER_Room *room);

/**
 * Get the contact of a member in a <i>room</i> identified by their <i>id</i>.
 *
 * Notice that contacts are independent of rooms but will be removed if all rooms containing these contacts get closed.
 *
 * @param room Room handle
 * @param id Hash identifying a member
 * @return Contact handle, NULL if <i>id</i> is not in use
 */
struct GNUNET_MESSENGER_Contact*
GNUNET_MESSENGER_get_member (const struct GNUNET_MESSENGER_Room *room, const struct GNUNET_ShortHashCode *id);

/**
 * Get the name used by the <i>contact</i>.
 *
 * @param contact Contact handle
 * @return Name of <i>contact</i> or NULL
 */
const char*
GNUNET_MESSENGER_contact_get_name (const struct GNUNET_MESSENGER_Contact *contact);

/**
 * Get the public key used by the <i>contact</i>.
 *
 * @param contact Contact handle
 * @return Public key of the ego used by <i>contact</i>
 */
const struct GNUNET_IDENTITY_PublicKey*
GNUNET_MESSENGER_contact_get_key (const struct GNUNET_MESSENGER_Contact *contact);

/**
 * Send a <i>message</i> into a </i>room</i>. If you opened the <i>room</i> all entered members will receive the
 * <i>message</i>. If you entered the <i>room</i> through a <b>door</b> all so entered <b>doors</b> will receive the
 * <i>message</i> as well. All members receiving the <i>message</i> will also propagate this <i>message</i> recursively
 * as long as the <i>message</i> is unknown to them.
 *
 * Notice that all messages sent and received are also stored and can be propagated to new members entering the room.
 *
 * @param room Room handle
 * @param message New message to send
 */
void
GNUNET_MESSENGER_send_message (struct GNUNET_MESSENGER_Room *room, const struct GNUNET_MESSENGER_Message *message);

/**
 * Get the message in a <i>room</i> identified by its <i>hash</i>.
 *
 * @param room Room handle
 * @param hash Hash identifying a message
 * @return Message struct or NULL if no message with that hash is known
 */
const struct GNUNET_MESSENGER_Message*
GNUNET_MESSENGER_get_message (const struct GNUNET_MESSENGER_Room *room, const struct GNUNET_HashCode *hash);

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

#endif //GNUNET_MESSENGER_SERVICE_H

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