xref: /btstack/src/classic/rfcomm.h (revision 2044a9b9ae072d40605300dae349cd05c5194e66)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 /*
39  *  RFCOMM.h
40  */
41 
42 #ifndef __RFCOMM_H
43 #define __RFCOMM_H
44 
45 #include "btstack_util.h"
46 
47 #include <stdint.h>
48 
49 #if defined __cplusplus
50 extern "C" {
51 #endif
52 
53 #define UNLIMITED_INCOMING_CREDITS 0xff
54 
55 #define RFCOMM_TEST_DATA_MAX_LEN 4
56 
57 #define RFCOMM_RLS_STATUS_INVALID 0xff
58 
59 
60 // private structs
61 typedef enum {
62 	RFCOMM_MULTIPLEXER_CLOSED = 1,
63 	RFCOMM_MULTIPLEXER_W4_CONNECT,  // outgoing
64 	RFCOMM_MULTIPLEXER_SEND_SABM_0,     //    "
65 	RFCOMM_MULTIPLEXER_W4_UA_0,     //    "
66 	RFCOMM_MULTIPLEXER_W4_SABM_0,   // incoming
67     RFCOMM_MULTIPLEXER_SEND_UA_0,
68 	RFCOMM_MULTIPLEXER_OPEN,
69     RFCOMM_MULTIPLEXER_SEND_UA_0_AND_DISC
70 } RFCOMM_MULTIPLEXER_STATE;
71 
72 typedef enum {
73     MULT_EV_READY_TO_SEND = 1,
74 
75 } RFCOMM_MULTIPLEXER_EVENT;
76 
77 typedef enum {
78 	RFCOMM_CHANNEL_CLOSED = 1,
79 	RFCOMM_CHANNEL_W4_MULTIPLEXER,
80 	RFCOMM_CHANNEL_SEND_UIH_PN,
81     RFCOMM_CHANNEL_W4_PN_RSP,
82 	RFCOMM_CHANNEL_SEND_SABM_W4_UA,
83 	RFCOMM_CHANNEL_W4_UA,
84     RFCOMM_CHANNEL_INCOMING_SETUP,
85     RFCOMM_CHANNEL_DLC_SETUP,
86 	RFCOMM_CHANNEL_OPEN,
87     RFCOMM_CHANNEL_SEND_UA_AFTER_DISC,
88     RFCOMM_CHANNEL_SEND_DISC,
89     RFCOMM_CHANNEL_W4_UA_AFTER_UA,
90     RFCOMM_CHANNEL_SEND_DM,
91 
92 } RFCOMM_CHANNEL_STATE;
93 
94 typedef enum {
95     RFCOMM_CHANNEL_STATE_VAR_NONE            = 0,
96     RFCOMM_CHANNEL_STATE_VAR_CLIENT_ACCEPTED = 1 << 0,
97     RFCOMM_CHANNEL_STATE_VAR_RCVD_PN         = 1 << 1,
98     RFCOMM_CHANNEL_STATE_VAR_RCVD_RPN        = 1 << 2,
99     RFCOMM_CHANNEL_STATE_VAR_RCVD_SABM       = 1 << 3,
100 
101     RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_CMD    = 1 << 4,
102     RFCOMM_CHANNEL_STATE_VAR_RCVD_MSC_RSP    = 1 << 5,
103     RFCOMM_CHANNEL_STATE_VAR_SEND_PN_RSP     = 1 << 6,
104     RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_INFO   = 1 << 7,
105 
106     RFCOMM_CHANNEL_STATE_VAR_SEND_RPN_RSP    = 1 << 8,
107     RFCOMM_CHANNEL_STATE_VAR_SEND_UA         = 1 << 9,
108     RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_CMD    = 1 << 10,
109     RFCOMM_CHANNEL_STATE_VAR_SEND_MSC_RSP    = 1 << 11,
110 
111     RFCOMM_CHANNEL_STATE_VAR_SEND_CREDITS    = 1 << 12,
112     RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_CMD    = 1 << 13,
113     RFCOMM_CHANNEL_STATE_VAR_SENT_MSC_RSP    = 1 << 14,
114     RFCOMM_CHANNEL_STATE_VAR_SENT_CREDITS    = 1 << 15,
115 } RFCOMM_CHANNEL_STATE_VAR;
116 
117 typedef enum {
118     CH_EVT_RCVD_SABM = 1,
119     CH_EVT_RCVD_UA,
120     CH_EVT_RCVD_PN,
121     CH_EVT_RCVD_PN_RSP,
122     CH_EVT_RCVD_DISC,
123     CH_EVT_RCVD_DM,
124     CH_EVT_RCVD_MSC_CMD,
125     CH_EVT_RCVD_MSC_RSP,
126     CH_EVT_RCVD_NSC_RSP,
127     CH_EVT_RCVD_RLS_CMD,
128     CH_EVT_RCVD_RLS_RSP,
129     CH_EVT_RCVD_RPN_CMD,
130     CH_EVT_RCVD_RPN_REQ,
131     CH_EVT_RCVD_CREDITS,
132     CH_EVT_MULTIPLEXER_READY,
133     CH_EVT_READY_TO_SEND,
134 } RFCOMM_CHANNEL_EVENT;
135 
136 typedef struct rfcomm_channel_event {
137     RFCOMM_CHANNEL_EVENT type;
138     uint16_t dummy; // force rfcomm_channel_event to be 2-byte aligned -> avoid -Wcast-align warning
139 } rfcomm_channel_event_t;
140 
141 typedef struct rfcomm_channel_event_pn {
142     rfcomm_channel_event_t super;
143     uint16_t max_frame_size;
144     uint8_t  priority;
145     uint8_t  credits_outgoing;
146 } rfcomm_channel_event_pn_t;
147 
148 typedef struct rfcomm_rpn_data {
149     uint8_t baud_rate;
150     uint8_t flags;
151     uint8_t flow_control;
152     uint8_t xon;
153     uint8_t xoff;
154     uint8_t parameter_mask_0;   // first byte
155     uint8_t parameter_mask_1;   // second byte
156 } rfcomm_rpn_data_t;
157 
158 typedef struct rfcomm_channel_event_rpn {
159     rfcomm_channel_event_t super;
160     rfcomm_rpn_data_t data;
161 } rfcomm_channel_event_rpn_t;
162 
163 typedef struct rfcomm_channel_event_rls {
164     rfcomm_channel_event_t super;
165     uint8_t line_status;
166 } rfcomm_channel_event_rls_t;
167 
168 typedef struct rfcomm_channel_event_msc {
169     rfcomm_channel_event_t super;
170     uint8_t modem_status;
171 } rfcomm_channel_event_msc_t;
172 
173 // info regarding potential connections
174 typedef struct {
175     // linked list - assert: first field
176     btstack_linked_item_t    item;
177 
178     // server channel
179     uint8_t server_channel;
180 
181     // incoming max frame size
182     uint16_t max_frame_size;
183 
184     // use incoming flow control
185     uint8_t incoming_flow_control;
186 
187     // initial incoming credits
188     uint8_t incoming_initial_credits;
189 
190     // internal connection
191     btstack_packet_handler_t packet_handler;
192 
193 } rfcomm_service_t;
194 
195 // info regarding multiplexer
196 // note: spec mandates single multiplexer per device combination
197 typedef struct {
198     // linked list - assert: first field
199     btstack_linked_item_t    item;
200 
201     btstack_timer_source_t   timer;
202     int              timer_active;
203 
204 	RFCOMM_MULTIPLEXER_STATE state;
205 
206     uint16_t  l2cap_cid;
207 
208     uint8_t   fcon; // only send if fcon & 1, send rsp if fcon & 0x80
209 
210 	bd_addr_t remote_addr;
211     hci_con_handle_t con_handle;
212 
213 	uint8_t   outgoing;
214 
215     // hack to deal with authentication failure only observed by remote side
216     uint8_t at_least_one_connection;
217 
218     uint16_t max_frame_size;
219 
220     // send DM for DLCI != 0
221     uint8_t send_dm_for_dlci;
222 
223     // non supported command, 0 if not set
224     uint8_t nsc_command;
225 
226     // test data - limited to RFCOMM_TEST_DATA_MAX_LEN
227     uint8_t test_data_len;
228     uint8_t test_data[RFCOMM_TEST_DATA_MAX_LEN];
229 
230 } rfcomm_multiplexer_t;
231 
232 // info regarding an actual connection
233 typedef struct {
234     // linked list - assert: first field
235     btstack_linked_item_t    item;
236 
237 	rfcomm_multiplexer_t *multiplexer;
238 	uint16_t rfcomm_cid;
239     uint8_t  outgoing;
240     uint8_t  dlci;
241 
242     // credits for outgoing traffic
243     uint8_t credits_outgoing;
244 
245     // number of packets remote will be granted
246     uint8_t new_credits_incoming;
247 
248     // credits for incoming traffic
249     uint8_t credits_incoming;
250 
251     // use incoming flow control
252     uint8_t incoming_flow_control;
253 
254     // channel state
255     RFCOMM_CHANNEL_STATE state;
256 
257     // state variables used in RFCOMM_CHANNEL_INCOMING
258     RFCOMM_CHANNEL_STATE_VAR state_var;
259 
260     // priority set by incoming side in PN
261     uint8_t pn_priority;
262 
263 	// negotiated frame size
264     uint16_t max_frame_size;
265 
266     // local rpn data
267     rfcomm_rpn_data_t rpn_data;
268 
269     // rls line status. RFCOMM_RLS_STATUS_INVALID if not set
270     uint8_t rls_line_status;
271 
272     // msc modem status.
273     uint8_t msc_modem_status;
274 
275 	// server channel (see rfcomm_service_t) - NULL => outgoing channel
276 	rfcomm_service_t * service;
277 
278     // internal connection
279     btstack_packet_handler_t packet_handler;
280 
281 } rfcomm_channel_t;
282 
283 /* API_START */
284 
285 /**
286  * @brief Set up RFCOMM.
287  */
288 void rfcomm_init(void);
289 
290 /**
291  * @brief Set security level required for incoming connections, need to be called before registering services.
292  */
293 void rfcomm_set_required_security_level(gap_security_level_t security_level);
294 
295 /**
296  * @brief Register packet handler.
297  */
298 void rfcomm_register_packet_handler(void (*handler)(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size));
299 
300 /*
301  * @brief Create RFCOMM connection to a given server channel on a remote deivce.
302  * This channel will automatically provide enough credits to the remote side.
303  * @param addr
304  * @param server_channel
305  * @param out_cid
306  * @result status
307  */
308 uint8_t rfcomm_create_channel(bd_addr_t addr, uint8_t server_channel, uint16_t * out_cid);
309 
310 /*
311  * @brief Create RFCOMM connection to a given server channel on a remote deivce.
312  * This channel will use explicit credit management. During channel establishment, an initial  amount of credits is provided.
313  * @param addr
314  * @param server_channel
315  * @param initial_credits
316  * @param out_cid
317  * @result status
318  */
319 uint8_t rfcomm_create_channel_with_initial_credits(bd_addr_t addr, uint8_t server_channel, uint8_t initial_credits, uint16_t * out_cid);
320 
321 /**
322  * @brief Disconnects RFCOMM channel with given identifier.
323  */
324 void rfcomm_disconnect(uint16_t rfcomm_cid);
325 
326 /**
327  * @brief Registers RFCOMM service for a server channel and a maximum frame size, and assigns a packet handler. On embedded systems, use NULL for connection parameter. This channel provides automatically enough credits to the remote side.
328  */
329 uint8_t rfcomm_register_service(uint8_t channel, uint16_t max_frame_size);
330 
331 /**
332  * @brief Registers RFCOMM service for a server channel and a maximum frame size, and assigns a packet handler. On embedded systems, use NULL for connection parameter. This channel will use explicit credit management. During channel establishment, an initial amount of credits is provided.
333  */
334 uint8_t rfcomm_register_service_with_initial_credits(uint8_t channel, uint16_t max_frame_size, uint8_t initial_credits);
335 
336 /**
337  * @brief Unregister RFCOMM service.
338  */
339 void rfcomm_unregister_service(uint8_t service_channel);
340 
341 /**
342  * @brief Accepts incoming RFCOMM connection.
343  */
344 void rfcomm_accept_connection(uint16_t rfcomm_cid);
345 
346 /**
347  * @brief Deny incoming RFCOMM connection.
348  */
349 void rfcomm_decline_connection(uint16_t rfcomm_cid);
350 
351 /**
352  * @brief Grant more incoming credits to the remote side for the given RFCOMM channel identifier.
353  */
354 void rfcomm_grant_credits(uint16_t rfcomm_cid, uint8_t credits);
355 
356 /**
357  * @brief Checks if RFCOMM can send packet. Returns yes if packet can be sent.
358  */
359 int rfcomm_can_send_packet_now(uint16_t rfcomm_cid);
360 
361 /**
362  * @brief Sends RFCOMM data packet to the RFCOMM channel with given identifier.
363  */
364 int  rfcomm_send(uint16_t rfcomm_cid, uint8_t *data, uint16_t len);
365 
366 /**
367  * @brief Sends Local Line Status, see LINE_STATUS_..
368  */
369 int rfcomm_send_local_line_status(uint16_t rfcomm_cid, uint8_t line_status);
370 
371 /**
372  * @brief Send local modem status. see MODEM_STAUS_..
373  */
374 int rfcomm_send_modem_status(uint16_t rfcomm_cid, uint8_t modem_status);
375 
376 /**
377  * @brief Configure remote port
378  */
379 int rfcomm_send_port_configuration(uint16_t rfcomm_cid, rpn_baud_t baud_rate, rpn_data_bits_t data_bits, rpn_stop_bits_t stop_bits, rpn_parity_t parity, rpn_flow_control_t flow_control);
380 
381 /**
382  * @brief Query remote port
383  */
384 int rfcomm_query_port_configuration(uint16_t rfcomm_cid);
385 
386 /**
387  * @brief Query max frame size
388  */
389 uint16_t  rfcomm_get_max_frame_size(uint16_t rfcomm_cid);
390 
391 /**
392  * @brief Allow to create RFCOMM packet in outgoing buffer.
393  * if (rfcomm_can_send_packet_now(cid)){
394  *     rfcomm_reserve_packet_buffer();
395  *     uint8_t * buffer = rfcomm_get_outgoing_buffer();
396  *     uint16_t buffer_size = rfcomm_get_max_frame_size(cid);
397  *     // .. setup data in buffer with len
398  *     rfcomm_send_prepared(cid, len)
399  * }
400  */
401 int       rfcomm_reserve_packet_buffer(void);
402 uint8_t * rfcomm_get_outgoing_buffer(void);
403 int       rfcomm_send_prepared(uint16_t rfcomm_cid, uint16_t len);
404 void      rfcomm_release_packet_buffer(void);
405 /* API_END */
406 
407 #if defined __cplusplus
408 }
409 #endif
410 
411 #endif // __RFCOMM_H
412