xref: /linux-6.15/include/uapi/linux/android/binder.h (revision 5cdcf4c6)
1 /*
2  * Copyright (C) 2008 Google, Inc.
3  *
4  * Based on, but no longer compatible with, the original
5  * OpenBinder.org binder driver interface, which is:
6  *
7  * Copyright (c) 2005 Palmsource, Inc.
8  *
9  * This software is licensed under the terms of the GNU General Public
10  * License version 2, as published by the Free Software Foundation, and
11  * may be copied, distributed, and modified under those terms.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  */
19 
20 #ifndef _UAPI_LINUX_BINDER_H
21 #define _UAPI_LINUX_BINDER_H
22 
23 #include <linux/types.h>
24 #include <linux/ioctl.h>
25 
26 #define B_PACK_CHARS(c1, c2, c3, c4) \
27 	((((c1)<<24)) | (((c2)<<16)) | (((c3)<<8)) | (c4))
28 #define B_TYPE_LARGE 0x85
29 
30 enum {
31 	BINDER_TYPE_BINDER	= B_PACK_CHARS('s', 'b', '*', B_TYPE_LARGE),
32 	BINDER_TYPE_WEAK_BINDER	= B_PACK_CHARS('w', 'b', '*', B_TYPE_LARGE),
33 	BINDER_TYPE_HANDLE	= B_PACK_CHARS('s', 'h', '*', B_TYPE_LARGE),
34 	BINDER_TYPE_WEAK_HANDLE	= B_PACK_CHARS('w', 'h', '*', B_TYPE_LARGE),
35 	BINDER_TYPE_FD		= B_PACK_CHARS('f', 'd', '*', B_TYPE_LARGE),
36 	BINDER_TYPE_FDA		= B_PACK_CHARS('f', 'd', 'a', B_TYPE_LARGE),
37 	BINDER_TYPE_PTR		= B_PACK_CHARS('p', 't', '*', B_TYPE_LARGE),
38 };
39 
40 enum {
41 	FLAT_BINDER_FLAG_PRIORITY_MASK = 0xff,
42 	FLAT_BINDER_FLAG_ACCEPTS_FDS = 0x100,
43 };
44 
45 #ifdef BINDER_IPC_32BIT
46 typedef __u32 binder_size_t;
47 typedef __u32 binder_uintptr_t;
48 #else
49 typedef __u64 binder_size_t;
50 typedef __u64 binder_uintptr_t;
51 #endif
52 
53 /**
54  * struct binder_object_header - header shared by all binder metadata objects.
55  * @type:	type of the object
56  */
57 struct binder_object_header {
58 	__u32        type;
59 };
60 
61 /*
62  * This is the flattened representation of a Binder object for transfer
63  * between processes.  The 'offsets' supplied as part of a binder transaction
64  * contains offsets into the data where these structures occur.  The Binder
65  * driver takes care of re-writing the structure type and data as it moves
66  * between processes.
67  */
68 struct flat_binder_object {
69 	struct binder_object_header	hdr;
70 	__u32				flags;
71 
72 	/* 8 bytes of data. */
73 	union {
74 		binder_uintptr_t	binder;	/* local object */
75 		__u32			handle;	/* remote object */
76 	};
77 
78 	/* extra data associated with local object */
79 	binder_uintptr_t	cookie;
80 };
81 
82 /**
83  * struct binder_fd_object - describes a filedescriptor to be fixed up.
84  * @hdr:	common header structure
85  * @pad_flags:	padding to remain compatible with old userspace code
86  * @pad_binder:	padding to remain compatible with old userspace code
87  * @fd:		file descriptor
88  * @cookie:	opaque data, used by user-space
89  */
90 struct binder_fd_object {
91 	struct binder_object_header	hdr;
92 	__u32				pad_flags;
93 	union {
94 		binder_uintptr_t	pad_binder;
95 		__u32			fd;
96 	};
97 
98 	binder_uintptr_t		cookie;
99 };
100 
101 /* struct binder_buffer_object - object describing a userspace buffer
102  * @hdr:		common header structure
103  * @flags:		one or more BINDER_BUFFER_* flags
104  * @buffer:		address of the buffer
105  * @length:		length of the buffer
106  * @parent:		index in offset array pointing to parent buffer
107  * @parent_offset:	offset in @parent pointing to this buffer
108  *
109  * A binder_buffer object represents an object that the
110  * binder kernel driver can copy verbatim to the target
111  * address space. A buffer itself may be pointed to from
112  * within another buffer, meaning that the pointer inside
113  * that other buffer needs to be fixed up as well. This
114  * can be done by setting the BINDER_BUFFER_FLAG_HAS_PARENT
115  * flag in @flags, by setting @parent buffer to the index
116  * in the offset array pointing to the parent binder_buffer_object,
117  * and by setting @parent_offset to the offset in the parent buffer
118  * at which the pointer to this buffer is located.
119  */
120 struct binder_buffer_object {
121 	struct binder_object_header	hdr;
122 	__u32				flags;
123 	binder_uintptr_t		buffer;
124 	binder_size_t			length;
125 	binder_size_t			parent;
126 	binder_size_t			parent_offset;
127 };
128 
129 enum {
130 	BINDER_BUFFER_FLAG_HAS_PARENT = 0x01,
131 };
132 
133 /* struct binder_fd_array_object - object describing an array of fds in a buffer
134  * @hdr:		common header structure
135  * @pad:		padding to ensure correct alignment
136  * @num_fds:		number of file descriptors in the buffer
137  * @parent:		index in offset array to buffer holding the fd array
138  * @parent_offset:	start offset of fd array in the buffer
139  *
140  * A binder_fd_array object represents an array of file
141  * descriptors embedded in a binder_buffer_object. It is
142  * different from a regular binder_buffer_object because it
143  * describes a list of file descriptors to fix up, not an opaque
144  * blob of memory, and hence the kernel needs to treat it differently.
145  *
146  * An example of how this would be used is with Android's
147  * native_handle_t object, which is a struct with a list of integers
148  * and a list of file descriptors. The native_handle_t struct itself
149  * will be represented by a struct binder_buffer_objct, whereas the
150  * embedded list of file descriptors is represented by a
151  * struct binder_fd_array_object with that binder_buffer_object as
152  * a parent.
153  */
154 struct binder_fd_array_object {
155 	struct binder_object_header	hdr;
156 	__u32				pad;
157 	binder_size_t			num_fds;
158 	binder_size_t			parent;
159 	binder_size_t			parent_offset;
160 };
161 
162 /*
163  * On 64-bit platforms where user code may run in 32-bits the driver must
164  * translate the buffer (and local binder) addresses appropriately.
165  */
166 
167 struct binder_write_read {
168 	binder_size_t		write_size;	/* bytes to write */
169 	binder_size_t		write_consumed;	/* bytes consumed by driver */
170 	binder_uintptr_t	write_buffer;
171 	binder_size_t		read_size;	/* bytes to read */
172 	binder_size_t		read_consumed;	/* bytes consumed by driver */
173 	binder_uintptr_t	read_buffer;
174 };
175 
176 /* Use with BINDER_VERSION, driver fills in fields. */
177 struct binder_version {
178 	/* driver protocol version -- increment with incompatible change */
179 	__s32       protocol_version;
180 };
181 
182 /* This is the current protocol version. */
183 #ifdef BINDER_IPC_32BIT
184 #define BINDER_CURRENT_PROTOCOL_VERSION 7
185 #else
186 #define BINDER_CURRENT_PROTOCOL_VERSION 8
187 #endif
188 
189 #define BINDER_WRITE_READ		_IOWR('b', 1, struct binder_write_read)
190 #define BINDER_SET_IDLE_TIMEOUT		_IOW('b', 3, __s64)
191 #define BINDER_SET_MAX_THREADS		_IOW('b', 5, __u32)
192 #define BINDER_SET_IDLE_PRIORITY	_IOW('b', 6, __s32)
193 #define BINDER_SET_CONTEXT_MGR		_IOW('b', 7, __s32)
194 #define BINDER_THREAD_EXIT		_IOW('b', 8, __s32)
195 #define BINDER_VERSION			_IOWR('b', 9, struct binder_version)
196 
197 /*
198  * NOTE: Two special error codes you should check for when calling
199  * in to the driver are:
200  *
201  * EINTR -- The operation has been interupted.  This should be
202  * handled by retrying the ioctl() until a different error code
203  * is returned.
204  *
205  * ECONNREFUSED -- The driver is no longer accepting operations
206  * from your process.  That is, the process is being destroyed.
207  * You should handle this by exiting from your process.  Note
208  * that once this error code is returned, all further calls to
209  * the driver from any thread will return this same code.
210  */
211 
212 enum transaction_flags {
213 	TF_ONE_WAY	= 0x01,	/* this is a one-way call: async, no return */
214 	TF_ROOT_OBJECT	= 0x04,	/* contents are the component's root object */
215 	TF_STATUS_CODE	= 0x08,	/* contents are a 32-bit status code */
216 	TF_ACCEPT_FDS	= 0x10,	/* allow replies with file descriptors */
217 };
218 
219 struct binder_transaction_data {
220 	/* The first two are only used for bcTRANSACTION and brTRANSACTION,
221 	 * identifying the target and contents of the transaction.
222 	 */
223 	union {
224 		/* target descriptor of command transaction */
225 		__u32	handle;
226 		/* target descriptor of return transaction */
227 		binder_uintptr_t ptr;
228 	} target;
229 	binder_uintptr_t	cookie;	/* target object cookie */
230 	__u32		code;		/* transaction command */
231 
232 	/* General information about the transaction. */
233 	__u32	        flags;
234 	pid_t		sender_pid;
235 	uid_t		sender_euid;
236 	binder_size_t	data_size;	/* number of bytes of data */
237 	binder_size_t	offsets_size;	/* number of bytes of offsets */
238 
239 	/* If this transaction is inline, the data immediately
240 	 * follows here; otherwise, it ends with a pointer to
241 	 * the data buffer.
242 	 */
243 	union {
244 		struct {
245 			/* transaction data */
246 			binder_uintptr_t	buffer;
247 			/* offsets from buffer to flat_binder_object structs */
248 			binder_uintptr_t	offsets;
249 		} ptr;
250 		__u8	buf[8];
251 	} data;
252 };
253 
254 struct binder_transaction_data_sg {
255 	struct binder_transaction_data transaction_data;
256 	binder_size_t buffers_size;
257 };
258 
259 struct binder_ptr_cookie {
260 	binder_uintptr_t ptr;
261 	binder_uintptr_t cookie;
262 };
263 
264 struct binder_handle_cookie {
265 	__u32 handle;
266 	binder_uintptr_t cookie;
267 } __packed;
268 
269 struct binder_pri_desc {
270 	__s32 priority;
271 	__u32 desc;
272 };
273 
274 struct binder_pri_ptr_cookie {
275 	__s32 priority;
276 	binder_uintptr_t ptr;
277 	binder_uintptr_t cookie;
278 };
279 
280 enum binder_driver_return_protocol {
281 	BR_ERROR = _IOR('r', 0, __s32),
282 	/*
283 	 * int: error code
284 	 */
285 
286 	BR_OK = _IO('r', 1),
287 	/* No parameters! */
288 
289 	BR_TRANSACTION = _IOR('r', 2, struct binder_transaction_data),
290 	BR_REPLY = _IOR('r', 3, struct binder_transaction_data),
291 	/*
292 	 * binder_transaction_data: the received command.
293 	 */
294 
295 	BR_ACQUIRE_RESULT = _IOR('r', 4, __s32),
296 	/*
297 	 * not currently supported
298 	 * int: 0 if the last bcATTEMPT_ACQUIRE was not successful.
299 	 * Else the remote object has acquired a primary reference.
300 	 */
301 
302 	BR_DEAD_REPLY = _IO('r', 5),
303 	/*
304 	 * The target of the last transaction (either a bcTRANSACTION or
305 	 * a bcATTEMPT_ACQUIRE) is no longer with us.  No parameters.
306 	 */
307 
308 	BR_TRANSACTION_COMPLETE = _IO('r', 6),
309 	/*
310 	 * No parameters... always refers to the last transaction requested
311 	 * (including replies).  Note that this will be sent even for
312 	 * asynchronous transactions.
313 	 */
314 
315 	BR_INCREFS = _IOR('r', 7, struct binder_ptr_cookie),
316 	BR_ACQUIRE = _IOR('r', 8, struct binder_ptr_cookie),
317 	BR_RELEASE = _IOR('r', 9, struct binder_ptr_cookie),
318 	BR_DECREFS = _IOR('r', 10, struct binder_ptr_cookie),
319 	/*
320 	 * void *:	ptr to binder
321 	 * void *: cookie for binder
322 	 */
323 
324 	BR_ATTEMPT_ACQUIRE = _IOR('r', 11, struct binder_pri_ptr_cookie),
325 	/*
326 	 * not currently supported
327 	 * int:	priority
328 	 * void *: ptr to binder
329 	 * void *: cookie for binder
330 	 */
331 
332 	BR_NOOP = _IO('r', 12),
333 	/*
334 	 * No parameters.  Do nothing and examine the next command.  It exists
335 	 * primarily so that we can replace it with a BR_SPAWN_LOOPER command.
336 	 */
337 
338 	BR_SPAWN_LOOPER = _IO('r', 13),
339 	/*
340 	 * No parameters.  The driver has determined that a process has no
341 	 * threads waiting to service incoming transactions.  When a process
342 	 * receives this command, it must spawn a new service thread and
343 	 * register it via bcENTER_LOOPER.
344 	 */
345 
346 	BR_FINISHED = _IO('r', 14),
347 	/*
348 	 * not currently supported
349 	 * stop threadpool thread
350 	 */
351 
352 	BR_DEAD_BINDER = _IOR('r', 15, binder_uintptr_t),
353 	/*
354 	 * void *: cookie
355 	 */
356 	BR_CLEAR_DEATH_NOTIFICATION_DONE = _IOR('r', 16, binder_uintptr_t),
357 	/*
358 	 * void *: cookie
359 	 */
360 
361 	BR_FAILED_REPLY = _IO('r', 17),
362 	/*
363 	 * The the last transaction (either a bcTRANSACTION or
364 	 * a bcATTEMPT_ACQUIRE) failed (e.g. out of memory).  No parameters.
365 	 */
366 };
367 
368 enum binder_driver_command_protocol {
369 	BC_TRANSACTION = _IOW('c', 0, struct binder_transaction_data),
370 	BC_REPLY = _IOW('c', 1, struct binder_transaction_data),
371 	/*
372 	 * binder_transaction_data: the sent command.
373 	 */
374 
375 	BC_ACQUIRE_RESULT = _IOW('c', 2, __s32),
376 	/*
377 	 * not currently supported
378 	 * int:  0 if the last BR_ATTEMPT_ACQUIRE was not successful.
379 	 * Else you have acquired a primary reference on the object.
380 	 */
381 
382 	BC_FREE_BUFFER = _IOW('c', 3, binder_uintptr_t),
383 	/*
384 	 * void *: ptr to transaction data received on a read
385 	 */
386 
387 	BC_INCREFS = _IOW('c', 4, __u32),
388 	BC_ACQUIRE = _IOW('c', 5, __u32),
389 	BC_RELEASE = _IOW('c', 6, __u32),
390 	BC_DECREFS = _IOW('c', 7, __u32),
391 	/*
392 	 * int:	descriptor
393 	 */
394 
395 	BC_INCREFS_DONE = _IOW('c', 8, struct binder_ptr_cookie),
396 	BC_ACQUIRE_DONE = _IOW('c', 9, struct binder_ptr_cookie),
397 	/*
398 	 * void *: ptr to binder
399 	 * void *: cookie for binder
400 	 */
401 
402 	BC_ATTEMPT_ACQUIRE = _IOW('c', 10, struct binder_pri_desc),
403 	/*
404 	 * not currently supported
405 	 * int: priority
406 	 * int: descriptor
407 	 */
408 
409 	BC_REGISTER_LOOPER = _IO('c', 11),
410 	/*
411 	 * No parameters.
412 	 * Register a spawned looper thread with the device.
413 	 */
414 
415 	BC_ENTER_LOOPER = _IO('c', 12),
416 	BC_EXIT_LOOPER = _IO('c', 13),
417 	/*
418 	 * No parameters.
419 	 * These two commands are sent as an application-level thread
420 	 * enters and exits the binder loop, respectively.  They are
421 	 * used so the binder can have an accurate count of the number
422 	 * of looping threads it has available.
423 	 */
424 
425 	BC_REQUEST_DEATH_NOTIFICATION = _IOW('c', 14,
426 						struct binder_handle_cookie),
427 	/*
428 	 * int: handle
429 	 * void *: cookie
430 	 */
431 
432 	BC_CLEAR_DEATH_NOTIFICATION = _IOW('c', 15,
433 						struct binder_handle_cookie),
434 	/*
435 	 * int: handle
436 	 * void *: cookie
437 	 */
438 
439 	BC_DEAD_BINDER_DONE = _IOW('c', 16, binder_uintptr_t),
440 	/*
441 	 * void *: cookie
442 	 */
443 
444 	BC_TRANSACTION_SG = _IOW('c', 17, struct binder_transaction_data_sg),
445 	BC_REPLY_SG = _IOW('c', 18, struct binder_transaction_data_sg),
446 	/*
447 	 * binder_transaction_data_sg: the sent command.
448 	 */
449 };
450 
451 #endif /* _UAPI_LINUX_BINDER_H */
452 
453