summaryrefslogtreecommitdiffstats
path: root/dbus/dbus-sysdeps.h
blob: eb395e0561814bf3ec0c5ff955313b20b56c2d80 (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
437
438
439
/* -*- mode: C; c-file-style: "gnu" -*- */
/* dbus-sysdeps.h Wrappers around system/libc features (internal to D-Bus implementation)
 * 
 * Copyright (C) 2002, 2003  Red Hat, Inc.
 * Copyright (C) 2003 CodeFactory AB
 *
 * Licensed under the Academic Free License version 2.1
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ifndef DBUS_SYSDEPS_H
#define DBUS_SYSDEPS_H

#include <config.h>

#include <dbus/dbus-errors.h>

/* this is perhaps bogus, but strcmp() etc. are faster if we use the
 * stuff straight out of string.h, so have this here for now.
 */
#include <string.h>

/* and it would just be annoying to abstract this */
#include <errno.h>

#include <stdarg.h>

DBUS_BEGIN_DECLS

/**
 * @addtogroup DBusSysdeps
 *
 * @{
 */

/* The idea of this file is to encapsulate everywhere that we're
 * relying on external libc features, for ease of security
 * auditing. The idea is from vsftpd. This also gives us a chance to
 * make things more convenient to use, e.g.  by reading into a
 * DBusString. Operating system headers aren't intended to be used
 * outside of this file and a limited number of others (such as
 * dbus-memory.c)
 */

/** An opaque string type */
typedef struct DBusString DBusString;

#if     __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)
#define _DBUS_GNUC_PRINTF( format_idx, arg_idx )    \
  __attribute__((__format__ (__printf__, format_idx, arg_idx)))
#define _DBUS_GNUC_NORETURN                         \
  __attribute__((__noreturn__))
#else   /* !__GNUC__ */
#define _DBUS_GNUC_PRINTF( format_idx, arg_idx )
#define _DBUS_GNUC_NORETURN
#endif  /* !__GNUC__ */

/** @def _DBUS_GNUC_PRINTF
 * used to tell gcc about printf format strings
 */
/** @def _DBUS_GNUC_NORETURN
 * used to tell gcc about functions that never return, such as _dbus_abort()
 */

void _dbus_abort (void) _DBUS_GNUC_NORETURN;

const char* _dbus_getenv (const char *varname);
dbus_bool_t _dbus_setenv (const char *varname,
			  const char *value);

/** A process ID */
typedef unsigned long dbus_pid_t;
/** A user ID */
typedef unsigned long dbus_uid_t;
/** A group ID */
typedef unsigned long dbus_gid_t;

/** an invalid PID used to represent an uninitialized dbus_pid_t field */
#define DBUS_PID_UNSET ((dbus_pid_t) -1)
/** an invalid UID used to represent an uninitialized dbus_uid_t field */
#define DBUS_UID_UNSET ((dbus_uid_t) -1)
/** an invalid GID used to represent an uninitialized dbus_gid_t field */
#define DBUS_GID_UNSET ((dbus_gid_t) -1)

/** an appropriate printf format for dbus_pid_t */
#define DBUS_PID_FORMAT "%lu"
/** an appropriate printf format for dbus_uid_t */
#define DBUS_UID_FORMAT "%lu"
/** an appropriate printf format for dbus_gid_t */
#define DBUS_GID_FORMAT "%lu"


/**
 * Socket interface
 *
 *  @todo Use for the file descriptors a struct
 *           - struct DBusSocket{ int d; }; -
 *        instead of int to get type-safety which 
 *        will be checked by the compiler.
 * 
 */

dbus_bool_t _dbus_open_tcp_socket  (int              *fd,
                                    DBusError        *error);
dbus_bool_t _dbus_close_socket     (int               fd,
                                    DBusError        *error);
int         _dbus_read_socket      (int               fd,
                                    DBusString       *buffer,
                                    int               count);
int         _dbus_write_socket     (int               fd,
                                    const DBusString *buffer,
                                    int               start,
                                    int               len);
int         _dbus_write_socket_two (int               fd,
                                    const DBusString *buffer1,
                                    int               start1,
                                    int               len1,
                                    const DBusString *buffer2,
                                    int               start2,
                                    int               len2);
int _dbus_connect_tcp_socket  (const char     *host,
                               dbus_uint32_t   port,
                               DBusError      *error);
int _dbus_listen_tcp_socket   (const char     *host,
                               dbus_uint32_t   port,
                               DBusError      *error);
int _dbus_accept              (int             listen_fd);

/**
 * Struct representing socket credentials
 */
typedef struct
{
  dbus_pid_t pid; /**< process ID or DBUS_PID_UNSET */
  dbus_uid_t uid; /**< user ID or DBUS_UID_UNSET */
  dbus_gid_t gid; /**< group ID or DBUS_GID_UNSET */
} DBusCredentials;

/* FIXME these read/send credentials should get moved to sysdeps-unix.h,
 * or renamed to reflect what they mean cross-platform
 */
dbus_bool_t _dbus_read_credentials_unix_socket (int              client_fd,
                                                DBusCredentials *credentials,
                                                DBusError       *error);
dbus_bool_t _dbus_send_credentials_unix_socket (int              server_fd,
                                                DBusError       *error);


void        _dbus_credentials_clear                (DBusCredentials       *credentials);
void        _dbus_credentials_from_current_process (DBusCredentials       *credentials);
dbus_bool_t _dbus_credentials_match                (const DBusCredentials *expected_credentials,
                                                    const DBusCredentials *provided_credentials);


/** Information about a UNIX user */
typedef struct DBusUserInfo  DBusUserInfo;
/** Information about a UNIX group */
typedef struct DBusGroupInfo DBusGroupInfo;

/**
 * Information about a UNIX user
 */
struct DBusUserInfo
{
  dbus_uid_t  uid;            /**< UID */
  dbus_gid_t  primary_gid;    /**< GID */
  dbus_gid_t *group_ids;      /**< Groups IDs, *including* above primary group */
  int         n_group_ids;    /**< Size of group IDs array */
  char       *username;       /**< Username */
  char       *homedir;        /**< Home directory */
};

/**
 * Information about a UNIX group
 */
struct DBusGroupInfo
{
  dbus_gid_t  gid;            /**< GID */
  char       *groupname;      /**< Group name */
};

dbus_bool_t _dbus_user_info_fill     (DBusUserInfo     *info,
                                      const DBusString *username,
                                      DBusError        *error);
dbus_bool_t _dbus_user_info_fill_uid (DBusUserInfo     *info,
                                      dbus_uid_t        uid,
                                      DBusError        *error);
void        _dbus_user_info_free     (DBusUserInfo     *info);

dbus_bool_t _dbus_group_info_fill     (DBusGroupInfo    *info,
                                       const DBusString *groupname,
                                       DBusError        *error);
dbus_bool_t _dbus_group_info_fill_gid (DBusGroupInfo    *info,
                                       dbus_gid_t        gid,
                                       DBusError        *error);
void        _dbus_group_info_free     (DBusGroupInfo    *info);


unsigned long _dbus_getpid (void);
dbus_uid_t    _dbus_getuid (void);
dbus_gid_t    _dbus_getgid (void);

/** Opaque type representing an atomically-modifiable integer
 * that can be used from multiple threads.
 */
typedef struct DBusAtomic DBusAtomic;

/**
 * An atomic integer safe to increment or decrement from multiple threads.
 */
struct DBusAtomic
{
  volatile dbus_int32_t value; /**< Value of the atomic integer. */
};

dbus_int32_t _dbus_atomic_inc (DBusAtomic *atomic);
dbus_int32_t _dbus_atomic_dec (DBusAtomic *atomic);

/** There is data to read */
#define _DBUS_POLLIN      0x0001
/** There is urgent data to read */
#define _DBUS_POLLPRI     0x0002
/** Writing now will not block */
#define _DBUS_POLLOUT     0x0004
/** Error condition */
#define _DBUS_POLLERR     0x0008
/** Hung up */
#define _DBUS_POLLHUP     0x0010
/** Invalid request: fd not open */
#define _DBUS_POLLNVAL    0x0020

/**
 * A portable struct pollfd wrapper. 
 */
typedef struct
{
  int fd;            /**< File descriptor */
  short events;      /**< Events to poll for */
  short revents;     /**< Events that occurred */
} DBusPollFD;

int _dbus_poll (DBusPollFD *fds,
                int         n_fds,
                int         timeout_milliseconds);

void _dbus_sleep_milliseconds (int milliseconds);

void _dbus_get_current_time (long *tv_sec,
                             long *tv_usec);

/**
 * File/directory interface
 */
dbus_bool_t _dbus_file_exists         (const char       *file);
dbus_bool_t _dbus_file_get_contents   (DBusString       *str,
                                       const DBusString *filename,
                                       DBusError        *error);
dbus_bool_t _dbus_string_save_to_file (const DBusString *str,
                                       const DBusString *filename,
                                       DBusError        *error);

dbus_bool_t _dbus_make_file_world_readable   (const DBusString *filename,
                                              DBusError *error);

dbus_bool_t    _dbus_create_file_exclusively (const DBusString *filename,
                                              DBusError        *error);
dbus_bool_t    _dbus_delete_file             (const DBusString *filename,
                                              DBusError        *error);
dbus_bool_t    _dbus_create_directory        (const DBusString *filename,
                                              DBusError        *error);
dbus_bool_t    _dbus_delete_directory        (const DBusString *filename,
					      DBusError        *error);

dbus_bool_t _dbus_concat_dir_and_file (DBusString       *dir,
                                       const DBusString *next_component);
dbus_bool_t _dbus_string_get_dirname  (const DBusString *filename,
                                       DBusString       *dirname);
dbus_bool_t _dbus_path_is_absolute    (const DBusString *filename);

/** Opaque type for reading a directory listing */
typedef struct DBusDirIter DBusDirIter;

DBusDirIter* _dbus_directory_open          (const DBusString *filename,
                                            DBusError        *error);
dbus_bool_t  _dbus_directory_get_next_file (DBusDirIter      *iter,
                                            DBusString       *filename,
                                            DBusError        *error);
void         _dbus_directory_close         (DBusDirIter      *iter);

dbus_bool_t  _dbus_check_dir_is_private_to_user    (DBusString *dir,
                                                    DBusError *error);

void _dbus_fd_set_close_on_exec (int fd);

const char* _dbus_get_tmpdir      (void);

/**
 * Random numbers 
 */
void        _dbus_generate_pseudorandom_bytes_buffer (char *buffer,
                                                      int   n_bytes);
void        _dbus_generate_random_bytes_buffer (char       *buffer,
                                                int         n_bytes);
dbus_bool_t _dbus_generate_random_bytes        (DBusString *str,
                                                int         n_bytes);
dbus_bool_t _dbus_generate_random_ascii        (DBusString *str,
                                                int         n_bytes);

const char* _dbus_error_from_errno (int error_number);

void _dbus_disable_sigpipe (void);


void _dbus_exit (int code) _DBUS_GNUC_NORETURN;

int _dbus_printf_string_upper_bound (const char *format,
                                     va_list args);


/**
 * Portable struct with stat() results
 */
typedef struct
{
  unsigned long mode;  /**< File mode */
  unsigned long nlink; /**< Number of hard links */
  dbus_uid_t    uid;   /**< User owning file */
  dbus_gid_t    gid;   /**< Group owning file */
  unsigned long size;  /**< Size of file */
  unsigned long atime; /**< Access time */
  unsigned long mtime; /**< Modify time */
  unsigned long ctime; /**< Creation time */
} DBusStat;

dbus_bool_t _dbus_stat             (const DBusString *filename,
                                    DBusStat         *statbuf,
                                    DBusError        *error);
dbus_bool_t _dbus_full_duplex_pipe (int              *fd1,
                                    int              *fd2,
                                    dbus_bool_t       blocking,
                                    DBusError        *error);

void        _dbus_print_backtrace  (void);

dbus_bool_t _dbus_become_daemon   (const DBusString *pidfile,
				   int               print_pid_fd,
                                   DBusError        *error);
dbus_bool_t _dbus_write_pid_file  (const DBusString *filename,
                                   unsigned long     pid,
                                   DBusError        *error);
dbus_bool_t _dbus_change_identity (unsigned long     uid,
                                   unsigned long     gid,
                                   DBusError        *error);

/** A UNIX signal handler */
typedef void (* DBusSignalHandler) (int sig);

void _dbus_set_signal_handler (int               sig,
                               DBusSignalHandler handler);

dbus_bool_t _dbus_user_at_console (const char *username,
                                   DBusError  *error);

/* Define DBUS_VA_COPY() to do the right thing for copying va_list variables. 
 * config.h may have already defined DBUS_VA_COPY as va_copy or __va_copy. 
 */
#if !defined (DBUS_VA_COPY)
#  if defined (__GNUC__) && defined (__PPC__) && (defined (_CALL_SYSV) || defined (_WIN32))
#    define DBUS_VA_COPY(ap1, ap2)   (*(ap1) = *(ap2))
#  elif defined (DBUS_VA_COPY_AS_ARRAY)
#    define DBUS_VA_COPY(ap1, ap2)   memcpy ((ap1), (ap2), sizeof (va_list))
#  else /* va_list is a pointer */
#    define DBUS_VA_COPY(ap1, ap2)   ((ap1) = (ap2))
#  endif /* va_list is a pointer */
#endif /* !DBUS_VA_COPY */


/**
 * Casts a primitive C type to a byte array and then indexes
 * a particular byte of the array.
 */
#define _DBUS_BYTE_OF_PRIMITIVE(p, i) \
    (((const char*)&(p))[(i)])
/** On x86 there is an 80-bit FPU, and if you do "a == b" it may have a
 * or b in an 80-bit register, thus failing to compare the two 64-bit
 * doubles for bitwise equality. So this macro compares the two doubles
 * bitwise.
 */
#define _DBUS_DOUBLES_BITWISE_EQUAL(a, b)                                       \
     (_DBUS_BYTE_OF_PRIMITIVE (a, 0) == _DBUS_BYTE_OF_PRIMITIVE (b, 0) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 1) == _DBUS_BYTE_OF_PRIMITIVE (b, 1) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 2) == _DBUS_BYTE_OF_PRIMITIVE (b, 2) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 3) == _DBUS_BYTE_OF_PRIMITIVE (b, 3) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 4) == _DBUS_BYTE_OF_PRIMITIVE (b, 4) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 5) == _DBUS_BYTE_OF_PRIMITIVE (b, 5) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 6) == _DBUS_BYTE_OF_PRIMITIVE (b, 6) &&       \
      _DBUS_BYTE_OF_PRIMITIVE (a, 7) == _DBUS_BYTE_OF_PRIMITIVE (b, 7))

dbus_bool_t _dbus_parse_uid (const DBusString  *uid_str,
                             dbus_uid_t        *uid);

dbus_bool_t _dbus_get_autolaunch_address (DBusString *address, 
					  DBusError *error);

/** Type representing a universally unique ID
 * @todo rename to UUID instead of GUID
 */
typedef union DBusGUID DBusGUID;

dbus_bool_t _dbus_read_local_machine_uuid   (DBusGUID         *machine_id,
                                             dbus_bool_t       create_if_not_found,
                                             DBusError        *error);

/**
 * Initialize threads as in dbus_threads_init_default(), appropriately
 * for the platform.
 * @returns #FALSE if no memory
 */
dbus_bool_t _dbus_threads_init_platform_specific (void);

/** @} */

DBUS_END_DECLS

#endif /* DBUS_SYSDEPS_H */