1 /* 2 * OS specific functions 3 * Copyright (c) 2005-2009, Jouni Malinen <j (at) w1.fi> 4 * 5 * This software may be distributed under the terms of the BSD license. 6 * See README for more details. 7 */ 8 9 #ifndef OS_H 10 #define OS_H 11 12 typedef long os_time_t; 13 14 /** 15 * os_sleep - Sleep (sec, usec) 16 * @sec: Number of seconds to sleep 17 * @usec: Number of microseconds to sleep 18 */ 19 void os_sleep(os_time_t sec, os_time_t usec); 20 21 struct os_time { 22 os_time_t sec; 23 os_time_t usec; 24 }; 25 26 struct os_reltime { 27 os_time_t sec; 28 os_time_t usec; 29 }; 30 31 /** 32 * os_get_time - Get current time (sec, usec) 33 * @t: Pointer to buffer for the time 34 * Returns: 0 on success, -1 on failure 35 */ 36 int os_get_time(struct os_time *t); 37 38 /** 39 * os_get_reltime - Get relative time (sec, usec) 40 * @t: Pointer to buffer for the time 41 * Returns: 0 on success, -1 on failure 42 */ 43 int os_get_reltime(struct os_reltime *t); 44 45 46 /* Helpers for handling struct os_time */ 47 48 static inline int os_time_before(struct os_time *a, struct os_time *b) 49 { 50 return (a->sec < b->sec) || 51 (a->sec == b->sec && a->usec < b->usec); 52 } 53 54 55 static inline void os_time_sub(struct os_time *a, struct os_time *b, 56 struct os_time *res) 57 { 58 res->sec = a->sec - b->sec; 59 res->usec = a->usec - b->usec; 60 if (res->usec < 0) { 61 res->sec--; 62 res->usec += 1000000; 63 } 64 } 65 66 67 /* Helpers for handling struct os_reltime */ 68 69 static inline int os_reltime_before(struct os_reltime *a, 70 struct os_reltime *b) 71 { 72 return (a->sec < b->sec) || 73 (a->sec == b->sec && a->usec < b->usec); 74 } 75 76 77 static inline void os_reltime_sub(struct os_reltime *a, struct os_reltime *b, 78 struct os_reltime *res) 79 { 80 res->sec = a->sec - b->sec; 81 res->usec = a->usec - b->usec; 82 if (res->usec < 0) { 83 res->sec--; 84 res->usec += 1000000; 85 } 86 } 87 88 89 static inline void os_reltime_age(struct os_reltime *start, 90 struct os_reltime *age) 91 { 92 struct os_reltime now; 93 94 os_get_reltime(&now); 95 os_reltime_sub(&now, start, age); 96 } 97 98 99 static inline int os_reltime_expired(struct os_reltime *now, 100 struct os_reltime *ts, 101 os_time_t timeout_secs) 102 { 103 struct os_reltime age; 104 105 os_reltime_sub(now, ts, &age); 106 return (age.sec > timeout_secs) || 107 (age.sec == timeout_secs && age.usec > 0); 108 } 109 110 111 static inline int os_reltime_initialized(struct os_reltime *t) 112 { 113 return t->sec != 0 || t->usec != 0; 114 } 115 116 117 /** 118 * os_mktime - Convert broken-down time into seconds since 1970-01-01 119 * @year: Four digit year 120 * @month: Month (1 .. 12) 121 * @day: Day of month (1 .. 31) 122 * @hour: Hour (0 .. 23) 123 * @min: Minute (0 .. 59) 124 * @sec: Second (0 .. 60) 125 * @t: Buffer for returning calendar time representation (seconds since 126 * 1970-01-01 00:00:00) 127 * Returns: 0 on success, -1 on failure 128 * 129 * Note: The result is in seconds from Epoch, i.e., in UTC, not in local time 130 * which is used by POSIX mktime(). 131 */ 132 int os_mktime(int year, int month, int day, int hour, int min, int sec, 133 os_time_t *t); 134 135 struct os_tm { 136 int sec; /* 0..59 or 60 for leap seconds */ 137 int min; /* 0..59 */ 138 int hour; /* 0..23 */ 139 int day; /* 1..31 */ 140 int month; /* 1..12 */ 141 int year; /* Four digit year */ 142 }; 143 144 int os_gmtime(os_time_t t, struct os_tm *tm); 145 146 /** 147 * os_daemonize - Run in the background (detach from the controlling terminal) 148 * @pid_file: File name to write the process ID to or %NULL to skip this 149 * Returns: 0 on success, -1 on failure 150 */ 151 int os_daemonize(const char *pid_file); 152 153 /** 154 * os_daemonize_terminate - Stop running in the background (remove pid file) 155 * @pid_file: File name to write the process ID to or %NULL to skip this 156 */ 157 void os_daemonize_terminate(const char *pid_file); 158 159 /** 160 * os_get_random - Get cryptographically strong pseudo random data 161 * @buf: Buffer for pseudo random data 162 * @len: Length of the buffer 163 * Returns: 0 on success, -1 on failure 164 */ 165 int os_get_random(unsigned char *buf, size_t len); 166 167 /** 168 * os_random - Get pseudo random value (not necessarily very strong) 169 * Returns: Pseudo random value 170 */ 171 unsigned long os_random(void); 172 173 /** 174 * os_rel2abs_path - Get an absolute path for a file 175 * @rel_path: Relative path to a file 176 * Returns: Absolute path for the file or %NULL on failure 177 * 178 * This function tries to convert a relative path of a file to an absolute path 179 * in order for the file to be found even if current working directory has 180 * changed. The returned value is allocated and caller is responsible for 181 * freeing it. It is acceptable to just return the same path in an allocated 182 * buffer, e.g., return strdup(rel_path). This function is only used to find 183 * configuration files when os_daemonize() may have changed the current working 184 * directory and relative path would be pointing to a different location. 185 */ 186 char * os_rel2abs_path(const char *rel_path); 187 188 /** 189 * os_program_init - Program initialization (called at start) 190 * Returns: 0 on success, -1 on failure 191 * 192 * This function is called when a programs starts. If there are any OS specific 193 * processing that is needed, it can be placed here. It is also acceptable to 194 * just return 0 if not special processing is needed. 195 */ 196 int os_program_init(void); 197 198 /** 199 * os_program_deinit - Program deinitialization (called just before exit) 200 * 201 * This function is called just before a program exists. If there are any OS 202 * specific processing, e.g., freeing resourced allocated in os_program_init(), 203 * it should be done here. It is also acceptable for this function to do 204 * nothing. 205 */ 206 void os_program_deinit(void); 207 208 /** 209 * os_setenv - Set environment variable 210 * @name: Name of the variable 211 * @value: Value to set to the variable 212 * @overwrite: Whether existing variable should be overwritten 213 * Returns: 0 on success, -1 on error 214 * 215 * This function is only used for wpa_cli action scripts. OS wrapper does not 216 * need to implement this if such functionality is not needed. 217 */ 218 int os_setenv(const char *name, const char *value, int overwrite); 219 220 /** 221 * os_unsetenv - Delete environent variable 222 * @name: Name of the variable 223 * Returns: 0 on success, -1 on error 224 * 225 * This function is only used for wpa_cli action scripts. OS wrapper does not 226 * need to implement this if such functionality is not needed. 227 */ 228 int os_unsetenv(const char *name); 229 230 /** 231 * os_readfile - Read a file to an allocated memory buffer 232 * @name: Name of the file to read 233 * @len: For returning the length of the allocated buffer 234 * Returns: Pointer to the allocated buffer or %NULL on failure 235 * 236 * This function allocates memory and reads the given file to this buffer. Both 237 * binary and text files can be read with this function. The caller is 238 * responsible for freeing the returned buffer with os_free(). 239 */ 240 char * os_readfile(const char *name, size_t *len); 241 242 /** 243 * os_file_exists - Check whether the specified file exists 244 * @fname: Path and name of the file 245 * Returns: 1 if the file exists or 0 if not 246 */ 247 int os_file_exists(const char *fname); 248 249 /** 250 * os_zalloc - Allocate and zero memory 251 * @size: Number of bytes to allocate 252 * Returns: Pointer to allocated and zeroed memory or %NULL on failure 253 * 254 * Caller is responsible for freeing the returned buffer with os_free(). 255 */ 256 void * os_zalloc(size_t size); 257 258 /** 259 * os_calloc - Allocate and zero memory for an array 260 * @nmemb: Number of members in the array 261 * @size: Number of bytes in each member 262 * Returns: Pointer to allocated and zeroed memory or %NULL on failure 263 * 264 * This function can be used as a wrapper for os_zalloc(nmemb * size) when an 265 * allocation is used for an array. The main benefit over os_zalloc() is in 266 * having an extra check to catch integer overflows in multiplication. 267 * 268 * Caller is responsible for freeing the returned buffer with os_free(). 269 */ 270 static inline void * os_calloc(size_t nmemb, size_t size) 271 { 272 if (size && nmemb > (~(size_t) 0) / size) 273 return NULL; 274 return os_zalloc(nmemb * size); 275 } 276 277 278 /* 279 * The following functions are wrapper for standard ANSI C or POSIX functions. 280 * By default, they are just defined to use the standard function name and no 281 * os_*.c implementation is needed for them. This avoids extra function calls 282 * by allowing the C pre-processor take care of the function name mapping. 283 * 284 * If the target system uses a C library that does not provide these functions, 285 * build_config.h can be used to define the wrappers to use a different 286 * function name. This can be done on function-by-function basis since the 287 * defines here are only used if build_config.h does not define the os_* name. 288 * If needed, os_*.c file can be used to implement the functions that are not 289 * included in the C library on the target system. Alternatively, 290 * OS_NO_C_LIB_DEFINES can be defined to skip all defines here in which case 291 * these functions need to be implemented in os_*.c file for the target system. 292 */ 293 294 #ifdef OS_NO_C_LIB_DEFINES 295 296 /** 297 * os_malloc - Allocate dynamic memory 298 * @size: Size of the buffer to allocate 299 * Returns: Allocated buffer or %NULL on failure 300 * 301 * Caller is responsible for freeing the returned buffer with os_free(). 302 */ 303 void * os_malloc(size_t size); 304 305 /** 306 * os_realloc - Re-allocate dynamic memory 307 * @ptr: Old buffer from os_malloc() or os_realloc() 308 * @size: Size of the new buffer 309 * Returns: Allocated buffer or %NULL on failure 310 * 311 * Caller is responsible for freeing the returned buffer with os_free(). 312 * If re-allocation fails, %NULL is returned and the original buffer (ptr) is 313 * not freed and caller is still responsible for freeing it. 314 */ 315 void * os_realloc(void *ptr, size_t size); 316 317 /** 318 * os_free - Free dynamic memory 319 * @ptr: Old buffer from os_malloc() or os_realloc(); can be %NULL 320 */ 321 void os_free(void *ptr); 322 323 /** 324 * os_memcpy - Copy memory area 325 * @dest: Destination 326 * @src: Source 327 * @n: Number of bytes to copy 328 * Returns: dest 329 * 330 * The memory areas src and dst must not overlap. os_memmove() can be used with 331 * overlapping memory. 332 */ 333 void * os_memcpy(void *dest, const void *src, size_t n); 334 335 /** 336 * os_memmove - Copy memory area 337 * @dest: Destination 338 * @src: Source 339 * @n: Number of bytes to copy 340 * Returns: dest 341 * 342 * The memory areas src and dst may overlap. 343 */ 344 void * os_memmove(void *dest, const void *src, size_t n); 345 346 /** 347 * os_memset - Fill memory with a constant byte 348 * @s: Memory area to be filled 349 * @c: Constant byte 350 * @n: Number of bytes started from s to fill with c 351 * Returns: s 352 */ 353 void * os_memset(void *s, int c, size_t n); 354 355 /** 356 * os_memcmp - Compare memory areas 357 * @s1: First buffer 358 * @s2: Second buffer 359 * @n: Maximum numbers of octets to compare 360 * Returns: An integer less than, equal to, or greater than zero if s1 is 361 * found to be less than, to match, or be greater than s2. Only first n 362 * characters will be compared. 363 */ 364 int os_memcmp(const void *s1, const void *s2, size_t n); 365 366 /** 367 * os_strdup - Duplicate a string 368 * @s: Source string 369 * Returns: Allocated buffer with the string copied into it or %NULL on failure 370 * 371 * Caller is responsible for freeing the returned buffer with os_free(). 372 */ 373 char * os_strdup(const char *s); 374 375 /** 376 * os_strlen - Calculate the length of a string 377 * @s: '\0' terminated string 378 * Returns: Number of characters in s (not counting the '\0' terminator) 379 */ 380 size_t os_strlen(const char *s); 381 382 /** 383 * os_strcasecmp - Compare two strings ignoring case 384 * @s1: First string 385 * @s2: Second string 386 * Returns: An integer less than, equal to, or greater than zero if s1 is 387 * found to be less than, to match, or be greatred than s2 388 */ 389 int os_strcasecmp(const char *s1, const char *s2); 390 391 /** 392 * os_strncasecmp - Compare two strings ignoring case 393 * @s1: First string 394 * @s2: Second string 395 * @n: Maximum numbers of characters to compare 396 * Returns: An integer less than, equal to, or greater than zero if s1 is 397 * found to be less than, to match, or be greater than s2. Only first n 398 * characters will be compared. 399 */ 400 int os_strncasecmp(const char *s1, const char *s2, size_t n); 401 402 /** 403 * os_strchr - Locate the first occurrence of a character in string 404 * @s: String 405 * @c: Character to search for 406 * Returns: Pointer to the matched character or %NULL if not found 407 */ 408 char * os_strchr(const char *s, int c); 409 410 /** 411 * os_strrchr - Locate the last occurrence of a character in string 412 * @s: String 413 * @c: Character to search for 414 * Returns: Pointer to the matched character or %NULL if not found 415 */ 416 char * os_strrchr(const char *s, int c); 417 418 /** 419 * os_strcmp - Compare two strings 420 * @s1: First string 421 * @s2: Second string 422 * Returns: An integer less than, equal to, or greater than zero if s1 is 423 * found to be less than, to match, or be greatred than s2 424 */ 425 int os_strcmp(const char *s1, const char *s2); 426 427 /** 428 * os_strncmp - Compare two strings 429 * @s1: First string 430 * @s2: Second string 431 * @n: Maximum numbers of characters to compare 432 * Returns: An integer less than, equal to, or greater than zero if s1 is 433 * found to be less than, to match, or be greater than s2. Only first n 434 * characters will be compared. 435 */ 436 int os_strncmp(const char *s1, const char *s2, size_t n); 437 438 /** 439 * os_strstr - Locate a substring 440 * @haystack: String (haystack) to search from 441 * @needle: Needle to search from haystack 442 * Returns: Pointer to the beginning of the substring or %NULL if not found 443 */ 444 char * os_strstr(const char *haystack, const char *needle); 445 446 /** 447 * os_snprintf - Print to a memory buffer 448 * @str: Memory buffer to print into 449 * @size: Maximum length of the str buffer 450 * @format: printf format 451 * Returns: Number of characters printed (not including trailing '\0'). 452 * 453 * If the output buffer is truncated, number of characters which would have 454 * been written is returned. Since some C libraries return -1 in such a case, 455 * the caller must be prepared on that value, too, to indicate truncation. 456 * 457 * Note: Some C library implementations of snprintf() may not guarantee null 458 * termination in case the output is truncated. The OS wrapper function of 459 * os_snprintf() should provide this guarantee, i.e., to null terminate the 460 * output buffer if a C library version of the function is used and if that 461 * function does not guarantee null termination. 462 * 463 * If the target system does not include snprintf(), see, e.g., 464 * http://www.ijs.si/software/snprintf/ for an example of a portable 465 * implementation of snprintf. 466 */ 467 int os_snprintf(char *str, size_t size, const char *format, ...); 468 469 #else /* OS_NO_C_LIB_DEFINES */ 470 471 #ifdef WPA_TRACE 472 void * os_malloc(size_t size); 473 void * os_realloc(void *ptr, size_t size); 474 void os_free(void *ptr); 475 char * os_strdup(const char *s); 476 #else /* WPA_TRACE */ 477 #ifndef os_malloc 478 #define os_malloc(s) malloc((s)) 479 #endif 480 #ifndef os_realloc 481 #define os_realloc(p, s) realloc((p), (s)) 482 #endif 483 #ifndef os_free 484 #define os_free(p) free((p)) 485 #endif 486 #ifndef os_strdup 487 #ifdef _MSC_VER 488 #define os_strdup(s) _strdup(s) 489 #else 490 #define os_strdup(s) strdup(s) 491 #endif 492 #endif 493 #endif /* WPA_TRACE */ 494 495 #ifndef os_memcpy 496 #define os_memcpy(d, s, n) memcpy((d), (s), (n)) 497 #endif 498 #ifndef os_memmove 499 #define os_memmove(d, s, n) memmove((d), (s), (n)) 500 #endif 501 #ifndef os_memset 502 #define os_memset(s, c, n) memset(s, c, n) 503 #endif 504 #ifndef os_memcmp 505 #define os_memcmp(s1, s2, n) memcmp((s1), (s2), (n)) 506 #endif 507 508 #ifndef os_strlen 509 #define os_strlen(s) strlen(s) 510 #endif 511 #ifndef os_strcasecmp 512 #ifdef _MSC_VER 513 #define os_strcasecmp(s1, s2) _stricmp((s1), (s2)) 514 #else 515 #define os_strcasecmp(s1, s2) strcasecmp((s1), (s2)) 516 #endif 517 #endif 518 #ifndef os_strncasecmp 519 #ifdef _MSC_VER 520 #define os_strncasecmp(s1, s2, n) _strnicmp((s1), (s2), (n)) 521 #else 522 #define os_strncasecmp(s1, s2, n) strncasecmp((s1), (s2), (n)) 523 #endif 524 #endif 525 #ifndef os_strchr 526 #define os_strchr(s, c) strchr((s), (c)) 527 #endif 528 #ifndef os_strcmp 529 #define os_strcmp(s1, s2) strcmp((s1), (s2)) 530 #endif 531 #ifndef os_strncmp 532 #define os_strncmp(s1, s2, n) strncmp((s1), (s2), (n)) 533 #endif 534 #ifndef os_strrchr 535 #define os_strrchr(s, c) strrchr((s), (c)) 536 #endif 537 #ifndef os_strstr 538 #define os_strstr(h, n) strstr((h), (n)) 539 #endif 540 541 #ifndef os_snprintf 542 #ifdef _MSC_VER 543 #define os_snprintf _snprintf 544 #else 545 #define os_snprintf snprintf 546 #endif 547 #endif 548 549 #endif /* OS_NO_C_LIB_DEFINES */ 550 551 552 static inline void * os_realloc_array(void *ptr, size_t nmemb, size_t size) 553 { 554 if (size && nmemb > (~(size_t) 0) / size) 555 return NULL; 556 return os_realloc(ptr, nmemb * size); 557 } 558 559 /** 560 * os_remove_in_array - Remove a member from an array by index 561 * @ptr: Pointer to the array 562 * @nmemb: Current member count of the array 563 * @size: The size per member of the array 564 * @idx: Index of the member to be removed 565 */ 566 static inline void os_remove_in_array(void *ptr, size_t nmemb, size_t size, 567 size_t idx) 568 { 569 if (idx < nmemb - 1) 570 os_memmove(((unsigned char *) ptr) + idx * size, 571 ((unsigned char *) ptr) + (idx + 1) * size, 572 (nmemb - idx - 1) * size); 573 } 574 575 /** 576 * os_strlcpy - Copy a string with size bound and NUL-termination 577 * @dest: Destination 578 * @src: Source 579 * @siz: Size of the target buffer 580 * Returns: Total length of the target string (length of src) (not including 581 * NUL-termination) 582 * 583 * This function matches in behavior with the strlcpy(3) function in OpenBSD. 584 */ 585 size_t os_strlcpy(char *dest, const char *src, size_t siz); 586 587 /** 588 * os_memcmp_const - Constant time memory comparison 589 * @a: First buffer to compare 590 * @b: Second buffer to compare 591 * @len: Number of octets to compare 592 * Returns: 0 if buffers are equal, non-zero if not 593 * 594 * This function is meant for comparing passwords or hash values where 595 * difference in execution time could provide external observer information 596 * about the location of the difference in the memory buffers. The return value 597 * does not behave like os_memcmp(), i.e., os_memcmp_const() cannot be used to 598 * sort items into a defined order. Unlike os_memcmp(), execution time of 599 * os_memcmp_const() does not depend on the contents of the compared memory 600 * buffers, but only on the total compared length. 601 */ 602 int os_memcmp_const(const void *a, const void *b, size_t len); 603 604 /** 605 * os_exec - Execute an external program 606 * @program: Path to the program 607 * @arg: Command line argument string 608 * @wait_completion: Whether to wait until the program execution completes 609 * Returns: 0 on success, -1 on error 610 */ 611 int os_exec(const char *program, const char *arg, int wait_completion); 612 613 614 #ifdef OS_REJECT_C_LIB_FUNCTIONS 615 #define malloc OS_DO_NOT_USE_malloc 616 #define realloc OS_DO_NOT_USE_realloc 617 #define free OS_DO_NOT_USE_free 618 #define memcpy OS_DO_NOT_USE_memcpy 619 #define memmove OS_DO_NOT_USE_memmove 620 #define memset OS_DO_NOT_USE_memset 621 #define memcmp OS_DO_NOT_USE_memcmp 622 #undef strdup 623 #define strdup OS_DO_NOT_USE_strdup 624 #define strlen OS_DO_NOT_USE_strlen 625 #define strcasecmp OS_DO_NOT_USE_strcasecmp 626 #define strncasecmp OS_DO_NOT_USE_strncasecmp 627 #undef strchr 628 #define strchr OS_DO_NOT_USE_strchr 629 #undef strcmp 630 #define strcmp OS_DO_NOT_USE_strcmp 631 #undef strncmp 632 #define strncmp OS_DO_NOT_USE_strncmp 633 #undef strncpy 634 #define strncpy OS_DO_NOT_USE_strncpy 635 #define strrchr OS_DO_NOT_USE_strrchr 636 #define strstr OS_DO_NOT_USE_strstr 637 #undef snprintf 638 #define snprintf OS_DO_NOT_USE_snprintf 639 640 #define strcpy OS_DO_NOT_USE_strcpy 641 #endif /* OS_REJECT_C_LIB_FUNCTIONS */ 642 643 #endif /* OS_H */ 644