1 /* -*- mode: C; c-file-style: "gnu" -*- */ 2 /* dbus-sysdeps.h Wrappers around system/libc features (internal to D-Bus implementation) 3 * 4 * Copyright (C) 2002, 2003 Red Hat, Inc. 5 * Copyright (C) 2003 CodeFactory AB 6 * 7 * Licensed under the Academic Free License version 2.1 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 */ 24 25 #ifndef DBUS_SYSDEPS_H 26 #define DBUS_SYSDEPS_H 27 28 #include <config.h> 29 30 #include <dbus/dbus-errors.h> 31 32 /* this is perhaps bogus, but strcmp() etc. are faster if we use the 33 * stuff straight out of string.h, so have this here for now. 34 */ 35 #include <string.h> 36 37 /* and it would just be annoying to abstract this */ 38 #include <errno.h> 39 40 #include <stdarg.h> 41 42 DBUS_BEGIN_DECLS 43 44 /* Forward declarations */ 45 46 /** An opaque string type */ 47 typedef struct DBusString DBusString; 48 49 /** An opaque list type */ 50 typedef struct DBusList DBusList; 51 52 /** 53 * @addtogroup DBusSysdeps 54 * 55 * @{ 56 */ 57 58 /* The idea of this file is to encapsulate everywhere that we're 59 * relying on external libc features, for ease of security 60 * auditing. The idea is from vsftpd. This also gives us a chance to 61 * make things more convenient to use, e.g. by reading into a 62 * DBusString. Operating system headers aren't intended to be used 63 * outside of this file and a limited number of others (such as 64 * dbus-memory.c) 65 */ 66 67 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4) 68 #define _DBUS_GNUC_PRINTF( format_idx, arg_idx ) \ 69 __attribute__((__format__ (__printf__, format_idx, arg_idx))) 70 #define _DBUS_GNUC_NORETURN \ 71 __attribute__((__noreturn__)) 72 #else /* !__GNUC__ */ 73 #define _DBUS_GNUC_PRINTF( format_idx, arg_idx ) 74 #define _DBUS_GNUC_NORETURN 75 #endif /* !__GNUC__ */ 76 77 /** @def _DBUS_GNUC_PRINTF 78 * used to tell gcc about printf format strings 79 */ 80 /** @def _DBUS_GNUC_NORETURN 81 * used to tell gcc about functions that never return, such as _dbus_abort() 82 */ 83 84 void _dbus_abort (void) _DBUS_GNUC_NORETURN; 85 86 const char* _dbus_getenv (const char *varname); 87 dbus_bool_t _dbus_setenv (const char *varname, 88 const char *value); 89 90 /** A process ID */ 91 typedef unsigned long dbus_pid_t; 92 /** A user ID */ 93 typedef unsigned long dbus_uid_t; 94 /** A group ID */ 95 typedef unsigned long dbus_gid_t; 96 97 /** an invalid PID used to represent an uninitialized dbus_pid_t field */ 98 #define DBUS_PID_UNSET ((dbus_pid_t) -1) 99 /** an invalid UID used to represent an uninitialized dbus_uid_t field */ 100 #define DBUS_UID_UNSET ((dbus_uid_t) -1) 101 /** an invalid GID used to represent an uninitialized dbus_gid_t field */ 102 #define DBUS_GID_UNSET ((dbus_gid_t) -1) 103 104 /** an appropriate printf format for dbus_pid_t */ 105 #define DBUS_PID_FORMAT "%lu" 106 /** an appropriate printf format for dbus_uid_t */ 107 #define DBUS_UID_FORMAT "%lu" 108 /** an appropriate printf format for dbus_gid_t */ 109 #define DBUS_GID_FORMAT "%lu" 110 111 112 /** 113 * Socket interface 114 * 115 * @todo Use for the file descriptors a struct 116 * - struct DBusSocket{ int d; }; - 117 * instead of int to get type-safety which 118 * will be checked by the compiler. 119 * 120 */ 121 122 dbus_bool_t _dbus_open_tcp_socket (int *fd, 123 DBusError *error); 124 dbus_bool_t _dbus_close_socket (int fd, 125 DBusError *error); 126 int _dbus_read_socket (int fd, 127 DBusString *buffer, 128 int count); 129 int _dbus_write_socket (int fd, 130 const DBusString *buffer, 131 int start, 132 int len); 133 int _dbus_write_socket_two (int fd, 134 const DBusString *buffer1, 135 int start1, 136 int len1, 137 const DBusString *buffer2, 138 int start2, 139 int len2); 140 int _dbus_connect_tcp_socket (const char *host, 141 dbus_uint32_t port, 142 DBusError *error); 143 int _dbus_listen_tcp_socket (const char *host, 144 dbus_uint32_t port, 145 DBusError *error); 146 int _dbus_accept (int listen_fd); 147 148 /** 149 * Struct representing socket credentials 150 */ 151 typedef struct 152 { 153 dbus_pid_t pid; /**< process ID or DBUS_PID_UNSET */ 154 dbus_uid_t uid; /**< user ID or DBUS_UID_UNSET */ 155 dbus_gid_t gid; /**< group ID or DBUS_GID_UNSET */ 156 } DBusCredentials; 157 158 /* FIXME these read/send credentials should get moved to sysdeps-unix.h, 159 * or renamed to reflect what they mean cross-platform 160 */ 161 dbus_bool_t _dbus_read_credentials_unix_socket (int client_fd, 162 DBusCredentials *credentials, 163 DBusError *error); 164 dbus_bool_t _dbus_send_credentials_unix_socket (int server_fd, 165 DBusError *error); 166 167 168 void _dbus_credentials_clear (DBusCredentials *credentials); 169 void _dbus_credentials_from_current_process (DBusCredentials *credentials); 170 dbus_bool_t _dbus_credentials_match (const DBusCredentials *expected_credentials, 171 const DBusCredentials *provided_credentials); 172 173 174 /** Information about a UNIX user */ 175 typedef struct DBusUserInfo DBusUserInfo; 176 /** Information about a UNIX group */ 177 typedef struct DBusGroupInfo DBusGroupInfo; 178 179 /** 180 * Information about a UNIX user 181 */ 182 struct DBusUserInfo 183 { 184 dbus_uid_t uid; /**< UID */ 185 dbus_gid_t primary_gid; /**< GID */ 186 dbus_gid_t *group_ids; /**< Groups IDs, *including* above primary group */ 187 int n_group_ids; /**< Size of group IDs array */ 188 char *username; /**< Username */ 189 char *homedir; /**< Home directory */ 190 }; 191 192 /** 193 * Information about a UNIX group 194 */ 195 struct DBusGroupInfo 196 { 197 dbus_gid_t gid; /**< GID */ 198 char *groupname; /**< Group name */ 199 }; 200 201 dbus_bool_t _dbus_user_info_fill (DBusUserInfo *info, 202 const DBusString *username, 203 DBusError *error); 204 dbus_bool_t _dbus_user_info_fill_uid (DBusUserInfo *info, 205 dbus_uid_t uid, 206 DBusError *error); 207 void _dbus_user_info_free (DBusUserInfo *info); 208 209 dbus_bool_t _dbus_group_info_fill (DBusGroupInfo *info, 210 const DBusString *groupname, 211 DBusError *error); 212 dbus_bool_t _dbus_group_info_fill_gid (DBusGroupInfo *info, 213 dbus_gid_t gid, 214 DBusError *error); 215 void _dbus_group_info_free (DBusGroupInfo *info); 216 217 218 unsigned long _dbus_getpid (void); 219 dbus_uid_t _dbus_getuid (void); 220 dbus_gid_t _dbus_getgid (void); 221 222 /** Opaque type representing an atomically-modifiable integer 223 * that can be used from multiple threads. 224 */ 225 typedef struct DBusAtomic DBusAtomic; 226 227 /** 228 * An atomic integer safe to increment or decrement from multiple threads. 229 */ 230 struct DBusAtomic 231 { 232 volatile dbus_int32_t value; /**< Value of the atomic integer. */ 233 }; 234 235 dbus_int32_t _dbus_atomic_inc (DBusAtomic *atomic); 236 dbus_int32_t _dbus_atomic_dec (DBusAtomic *atomic); 237 238 /** There is data to read */ 239 #define _DBUS_POLLIN 0x0001 240 /** There is urgent data to read */ 241 #define _DBUS_POLLPRI 0x0002 242 /** Writing now will not block */ 243 #define _DBUS_POLLOUT 0x0004 244 /** Error condition */ 245 #define _DBUS_POLLERR 0x0008 246 /** Hung up */ 247 #define _DBUS_POLLHUP 0x0010 248 /** Invalid request: fd not open */ 249 #define _DBUS_POLLNVAL 0x0020 250 251 /** 252 * A portable struct pollfd wrapper. 253 */ 254 typedef struct 255 { 256 int fd; /**< File descriptor */ 257 short events; /**< Events to poll for */ 258 short revents; /**< Events that occurred */ 259 } DBusPollFD; 260 261 int _dbus_poll (DBusPollFD *fds, 262 int n_fds, 263 int timeout_milliseconds); 264 265 void _dbus_sleep_milliseconds (int milliseconds); 266 267 void _dbus_get_current_time (long *tv_sec, 268 long *tv_usec); 269 270 /** 271 * File/directory interface 272 */ 273 dbus_bool_t _dbus_file_exists (const char *file); 274 dbus_bool_t _dbus_file_get_contents (DBusString *str, 275 const DBusString *filename, 276 DBusError *error); 277 dbus_bool_t _dbus_string_save_to_file (const DBusString *str, 278 const DBusString *filename, 279 DBusError *error); 280 281 dbus_bool_t _dbus_make_file_world_readable (const DBusString *filename, 282 DBusError *error); 283 284 dbus_bool_t _dbus_create_file_exclusively (const DBusString *filename, 285 DBusError *error); 286 dbus_bool_t _dbus_delete_file (const DBusString *filename, 287 DBusError *error); 288 dbus_bool_t _dbus_create_directory (const DBusString *filename, 289 DBusError *error); 290 dbus_bool_t _dbus_delete_directory (const DBusString *filename, 291 DBusError *error); 292 293 dbus_bool_t _dbus_concat_dir_and_file (DBusString *dir, 294 const DBusString *next_component); 295 dbus_bool_t _dbus_string_get_dirname (const DBusString *filename, 296 DBusString *dirname); 297 dbus_bool_t _dbus_path_is_absolute (const DBusString *filename); 298 299 dbus_bool_t _dbus_get_standard_session_servicedirs (DBusList **dirs); 300 301 /** Opaque type for reading a directory listing */ 302 typedef struct DBusDirIter DBusDirIter; 303 304 DBusDirIter* _dbus_directory_open (const DBusString *filename, 305 DBusError *error); 306 dbus_bool_t _dbus_directory_get_next_file (DBusDirIter *iter, 307 DBusString *filename, 308 DBusError *error); 309 void _dbus_directory_close (DBusDirIter *iter); 310 311 dbus_bool_t _dbus_check_dir_is_private_to_user (DBusString *dir, 312 DBusError *error); 313 314 void _dbus_fd_set_close_on_exec (int fd); 315 316 const char* _dbus_get_tmpdir (void); 317 318 /** 319 * Random numbers 320 */ 321 void _dbus_generate_pseudorandom_bytes_buffer (char *buffer, 322 int n_bytes); 323 void _dbus_generate_random_bytes_buffer (char *buffer, 324 int n_bytes); 325 dbus_bool_t _dbus_generate_random_bytes (DBusString *str, 326 int n_bytes); 327 dbus_bool_t _dbus_generate_random_ascii (DBusString *str, 328 int n_bytes); 329 330 const char* _dbus_error_from_errno (int error_number); 331 332 void _dbus_disable_sigpipe (void); 333 334 335 void _dbus_exit (int code) _DBUS_GNUC_NORETURN; 336 337 int _dbus_printf_string_upper_bound (const char *format, 338 va_list args); 339 340 341 /** 342 * Portable struct with stat() results 343 */ 344 typedef struct 345 { 346 unsigned long mode; /**< File mode */ 347 unsigned long nlink; /**< Number of hard links */ 348 dbus_uid_t uid; /**< User owning file */ 349 dbus_gid_t gid; /**< Group owning file */ 350 unsigned long size; /**< Size of file */ 351 unsigned long atime; /**< Access time */ 352 unsigned long mtime; /**< Modify time */ 353 unsigned long ctime; /**< Creation time */ 354 } DBusStat; 355 356 dbus_bool_t _dbus_stat (const DBusString *filename, 357 DBusStat *statbuf, 358 DBusError *error); 359 dbus_bool_t _dbus_full_duplex_pipe (int *fd1, 360 int *fd2, 361 dbus_bool_t blocking, 362 DBusError *error); 363 364 void _dbus_print_backtrace (void); 365 366 dbus_bool_t _dbus_become_daemon (const DBusString *pidfile, 367 int print_pid_fd, 368 DBusError *error); 369 dbus_bool_t _dbus_write_pid_file (const DBusString *filename, 370 unsigned long pid, 371 DBusError *error); 372 dbus_bool_t _dbus_change_identity (unsigned long uid, 373 unsigned long gid, 374 DBusError *error); 375 376 /** A UNIX signal handler */ 377 typedef void (* DBusSignalHandler) (int sig); 378 379 void _dbus_set_signal_handler (int sig, 380 DBusSignalHandler handler); 381 382 dbus_bool_t _dbus_user_at_console (const char *username, 383 DBusError *error); 384 385 /* Define DBUS_VA_COPY() to do the right thing for copying va_list variables. 386 * config.h may have already defined DBUS_VA_COPY as va_copy or __va_copy. 387 */ 388 #if !defined (DBUS_VA_COPY) 389 # if defined (__GNUC__) && defined (__PPC__) && (defined (_CALL_SYSV) || defined (_WIN32)) 390 # define DBUS_VA_COPY(ap1, ap2) (*(ap1) = *(ap2)) 391 # elif defined (DBUS_VA_COPY_AS_ARRAY) 392 # define DBUS_VA_COPY(ap1, ap2) memcpy ((ap1), (ap2), sizeof (va_list)) 393 # else /* va_list is a pointer */ 394 # define DBUS_VA_COPY(ap1, ap2) ((ap1) = (ap2)) 395 # endif /* va_list is a pointer */ 396 #endif /* !DBUS_VA_COPY */ 397 398 399 /** 400 * Casts a primitive C type to a byte array and then indexes 401 * a particular byte of the array. 402 */ 403 #define _DBUS_BYTE_OF_PRIMITIVE(p, i) \ 404 (((const char*)&(p))[(i)]) 405 /** On x86 there is an 80-bit FPU, and if you do "a == b" it may have a 406 * or b in an 80-bit register, thus failing to compare the two 64-bit 407 * doubles for bitwise equality. So this macro compares the two doubles 408 * bitwise. 409 */ 410 #define _DBUS_DOUBLES_BITWISE_EQUAL(a, b) \ 411 (_DBUS_BYTE_OF_PRIMITIVE (a, 0) == _DBUS_BYTE_OF_PRIMITIVE (b, 0) && \ 412 _DBUS_BYTE_OF_PRIMITIVE (a, 1) == _DBUS_BYTE_OF_PRIMITIVE (b, 1) && \ 413 _DBUS_BYTE_OF_PRIMITIVE (a, 2) == _DBUS_BYTE_OF_PRIMITIVE (b, 2) && \ 414 _DBUS_BYTE_OF_PRIMITIVE (a, 3) == _DBUS_BYTE_OF_PRIMITIVE (b, 3) && \ 415 _DBUS_BYTE_OF_PRIMITIVE (a, 4) == _DBUS_BYTE_OF_PRIMITIVE (b, 4) && \ 416 _DBUS_BYTE_OF_PRIMITIVE (a, 5) == _DBUS_BYTE_OF_PRIMITIVE (b, 5) && \ 417 _DBUS_BYTE_OF_PRIMITIVE (a, 6) == _DBUS_BYTE_OF_PRIMITIVE (b, 6) && \ 418 _DBUS_BYTE_OF_PRIMITIVE (a, 7) == _DBUS_BYTE_OF_PRIMITIVE (b, 7)) 419 420 dbus_bool_t _dbus_parse_uid (const DBusString *uid_str, 421 dbus_uid_t *uid); 422 423 dbus_bool_t _dbus_get_autolaunch_address (DBusString *address, 424 DBusError *error); 425 426 /** Type representing a universally unique ID 427 * @todo rename to UUID instead of GUID 428 */ 429 typedef union DBusGUID DBusGUID; 430 431 dbus_bool_t _dbus_read_local_machine_uuid (DBusGUID *machine_id, 432 dbus_bool_t create_if_not_found, 433 DBusError *error); 434 435 /** 436 * Initialize threads as in dbus_threads_init_default(), appropriately 437 * for the platform. 438 * @returns #FALSE if no memory 439 */ 440 dbus_bool_t _dbus_threads_init_platform_specific (void); 441 442 /** @} */ 443 444 DBUS_END_DECLS 445 446 #endif /* DBUS_SYSDEPS_H */ 447
