1/*
2 * OS specific functions
3 * Copyright (c) 2005-2009, Jouni Malinen <j@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#include <stdio.h>
12
13typedef long os_time_t;
14
15/**
16 * os_sleep - Sleep (sec, usec)
17 * @sec: Number of seconds to sleep
18 * @usec: Number of microseconds to sleep
19 */
20void os_sleep(os_time_t sec, os_time_t usec);
21
22struct os_time {
23	os_time_t sec;
24	os_time_t usec;
25};
26
27struct os_reltime {
28	os_time_t sec;
29	os_time_t usec;
30};
31
32/**
33 * os_get_time - Get current time (sec, usec)
34 * @t: Pointer to buffer for the time
35 * Returns: 0 on success, -1 on failure
36 */
37int os_get_time(struct os_time *t);
38
39/**
40 * os_get_reltime - Get relative time (sec, usec)
41 * @t: Pointer to buffer for the time
42 * Returns: 0 on success, -1 on failure
43 */
44int os_get_reltime(struct os_reltime *t);
45
46
47/* Helpers for handling struct os_time */
48
49static inline int os_time_before(struct os_time *a, struct os_time *b)
50{
51	return (a->sec < b->sec) ||
52	       (a->sec == b->sec && a->usec < b->usec);
53}
54
55
56static inline void os_time_sub(struct os_time *a, struct os_time *b,
57			       struct os_time *res)
58{
59	res->sec = a->sec - b->sec;
60	res->usec = a->usec - b->usec;
61	if (res->usec < 0) {
62		res->sec--;
63		res->usec += 1000000;
64	}
65}
66
67
68/* Helpers for handling struct os_reltime */
69
70static inline int os_reltime_before(struct os_reltime *a,
71				    struct os_reltime *b)
72{
73	return (a->sec < b->sec) ||
74	       (a->sec == b->sec && a->usec < b->usec);
75}
76
77
78static inline void os_reltime_sub(struct os_reltime *a, struct os_reltime *b,
79				  struct os_reltime *res)
80{
81	res->sec = a->sec - b->sec;
82	res->usec = a->usec - b->usec;
83	if (res->usec < 0) {
84		res->sec--;
85		res->usec += 1000000;
86	}
87}
88
89
90static inline void os_reltime_age(struct os_reltime *start,
91				  struct os_reltime *age)
92{
93	struct os_reltime now;
94
95	os_get_reltime(&now);
96	os_reltime_sub(&now, start, age);
97}
98
99
100static inline int os_reltime_expired(struct os_reltime *now,
101				     struct os_reltime *ts,
102				     os_time_t timeout_secs)
103{
104	struct os_reltime age;
105
106	os_reltime_sub(now, ts, &age);
107	return (age.sec > timeout_secs) ||
108	       (age.sec == timeout_secs && age.usec > 0);
109}
110
111
112static inline int os_reltime_initialized(struct os_reltime *t)
113{
114	return t->sec != 0 || t->usec != 0;
115}
116
117
118/**
119 * os_mktime - Convert broken-down time into seconds since 1970-01-01
120 * @year: Four digit year
121 * @month: Month (1 .. 12)
122 * @day: Day of month (1 .. 31)
123 * @hour: Hour (0 .. 23)
124 * @min: Minute (0 .. 59)
125 * @sec: Second (0 .. 60)
126 * @t: Buffer for returning calendar time representation (seconds since
127 * 1970-01-01 00:00:00)
128 * Returns: 0 on success, -1 on failure
129 *
130 * Note: The result is in seconds from Epoch, i.e., in UTC, not in local time
131 * which is used by POSIX mktime().
132 */
133int os_mktime(int year, int month, int day, int hour, int min, int sec,
134	      os_time_t *t);
135
136struct os_tm {
137	int sec; /* 0..59 or 60 for leap seconds */
138	int min; /* 0..59 */
139	int hour; /* 0..23 */
140	int day; /* 1..31 */
141	int month; /* 1..12 */
142	int year; /* Four digit year */
143};
144
145int os_gmtime(os_time_t t, struct os_tm *tm);
146
147/**
148 * os_daemonize - Run in the background (detach from the controlling terminal)
149 * @pid_file: File name to write the process ID to or %NULL to skip this
150 * Returns: 0 on success, -1 on failure
151 */
152int os_daemonize(const char *pid_file);
153
154/**
155 * os_daemonize_terminate - Stop running in the background (remove pid file)
156 * @pid_file: File name to write the process ID to or %NULL to skip this
157 */
158void os_daemonize_terminate(const char *pid_file);
159
160/**
161 * os_get_random - Get cryptographically strong pseudo random data
162 * @buf: Buffer for pseudo random data
163 * @len: Length of the buffer
164 * Returns: 0 on success, -1 on failure
165 */
166int os_get_random(unsigned char *buf, size_t len);
167
168/**
169 * os_random - Get pseudo random value (not necessarily very strong)
170 * Returns: Pseudo random value
171 */
172unsigned long os_random(void);
173
174/**
175 * os_rel2abs_path - Get an absolute path for a file
176 * @rel_path: Relative path to a file
177 * Returns: Absolute path for the file or %NULL on failure
178 *
179 * This function tries to convert a relative path of a file to an absolute path
180 * in order for the file to be found even if current working directory has
181 * changed. The returned value is allocated and caller is responsible for
182 * freeing it. It is acceptable to just return the same path in an allocated
183 * buffer, e.g., return strdup(rel_path). This function is only used to find
184 * configuration files when os_daemonize() may have changed the current working
185 * directory and relative path would be pointing to a different location.
186 */
187char * os_rel2abs_path(const char *rel_path);
188
189/**
190 * os_program_init - Program initialization (called at start)
191 * Returns: 0 on success, -1 on failure
192 *
193 * This function is called when a programs starts. If there are any OS specific
194 * processing that is needed, it can be placed here. It is also acceptable to
195 * just return 0 if not special processing is needed.
196 */
197int os_program_init(void);
198
199/**
200 * os_program_deinit - Program deinitialization (called just before exit)
201 *
202 * This function is called just before a program exists. If there are any OS
203 * specific processing, e.g., freeing resourced allocated in os_program_init(),
204 * it should be done here. It is also acceptable for this function to do
205 * nothing.
206 */
207void os_program_deinit(void);
208
209/**
210 * os_setenv - Set environment variable
211 * @name: Name of the variable
212 * @value: Value to set to the variable
213 * @overwrite: Whether existing variable should be overwritten
214 * Returns: 0 on success, -1 on error
215 *
216 * This function is only used for wpa_cli action scripts. OS wrapper does not
217 * need to implement this if such functionality is not needed.
218 */
219int os_setenv(const char *name, const char *value, int overwrite);
220
221/**
222 * os_unsetenv - Delete environent variable
223 * @name: Name of the variable
224 * Returns: 0 on success, -1 on error
225 *
226 * This function is only used for wpa_cli action scripts. OS wrapper does not
227 * need to implement this if such functionality is not needed.
228 */
229int os_unsetenv(const char *name);
230
231/**
232 * os_readfile - Read a file to an allocated memory buffer
233 * @name: Name of the file to read
234 * @len: For returning the length of the allocated buffer
235 * Returns: Pointer to the allocated buffer or %NULL on failure
236 *
237 * This function allocates memory and reads the given file to this buffer. Both
238 * binary and text files can be read with this function. The caller is
239 * responsible for freeing the returned buffer with os_free().
240 */
241char * os_readfile(const char *name, size_t *len);
242
243/**
244 * os_file_exists - Check whether the specified file exists
245 * @fname: Path and name of the file
246 * Returns: 1 if the file exists or 0 if not
247 */
248int os_file_exists(const char *fname);
249
250/**
251 * os_fdatasync - Sync a file's (for a given stream) state with storage device
252 * @stream: the stream to be flushed
253 * Returns: 0 if the operation succeeded or -1 on failure
254 */
255int os_fdatasync(FILE *stream);
256
257/**
258 * os_zalloc - Allocate and zero memory
259 * @size: Number of bytes to allocate
260 * Returns: Pointer to allocated and zeroed memory or %NULL on failure
261 *
262 * Caller is responsible for freeing the returned buffer with os_free().
263 */
264void * os_zalloc(size_t size);
265
266/**
267 * os_calloc - Allocate and zero memory for an array
268 * @nmemb: Number of members in the array
269 * @size: Number of bytes in each member
270 * Returns: Pointer to allocated and zeroed memory or %NULL on failure
271 *
272 * This function can be used as a wrapper for os_zalloc(nmemb * size) when an
273 * allocation is used for an array. The main benefit over os_zalloc() is in
274 * having an extra check to catch integer overflows in multiplication.
275 *
276 * Caller is responsible for freeing the returned buffer with os_free().
277 */
278static inline void * os_calloc(size_t nmemb, size_t size)
279{
280	if (size && nmemb > (~(size_t) 0) / size)
281		return NULL;
282	return os_zalloc(nmemb * size);
283}
284
285
286/*
287 * The following functions are wrapper for standard ANSI C or POSIX functions.
288 * By default, they are just defined to use the standard function name and no
289 * os_*.c implementation is needed for them. This avoids extra function calls
290 * by allowing the C pre-processor take care of the function name mapping.
291 *
292 * If the target system uses a C library that does not provide these functions,
293 * build_config.h can be used to define the wrappers to use a different
294 * function name. This can be done on function-by-function basis since the
295 * defines here are only used if build_config.h does not define the os_* name.
296 * If needed, os_*.c file can be used to implement the functions that are not
297 * included in the C library on the target system. Alternatively,
298 * OS_NO_C_LIB_DEFINES can be defined to skip all defines here in which case
299 * these functions need to be implemented in os_*.c file for the target system.
300 */
301
302#ifdef OS_NO_C_LIB_DEFINES
303
304/**
305 * os_malloc - Allocate dynamic memory
306 * @size: Size of the buffer to allocate
307 * Returns: Allocated buffer or %NULL on failure
308 *
309 * Caller is responsible for freeing the returned buffer with os_free().
310 */
311void * os_malloc(size_t size);
312
313/**
314 * os_realloc - Re-allocate dynamic memory
315 * @ptr: Old buffer from os_malloc() or os_realloc()
316 * @size: Size of the new buffer
317 * Returns: Allocated buffer or %NULL on failure
318 *
319 * Caller is responsible for freeing the returned buffer with os_free().
320 * If re-allocation fails, %NULL is returned and the original buffer (ptr) is
321 * not freed and caller is still responsible for freeing it.
322 */
323void * os_realloc(void *ptr, size_t size);
324
325/**
326 * os_free - Free dynamic memory
327 * @ptr: Old buffer from os_malloc() or os_realloc(); can be %NULL
328 */
329void os_free(void *ptr);
330
331/**
332 * os_memcpy - Copy memory area
333 * @dest: Destination
334 * @src: Source
335 * @n: Number of bytes to copy
336 * Returns: dest
337 *
338 * The memory areas src and dst must not overlap. os_memmove() can be used with
339 * overlapping memory.
340 */
341void * os_memcpy(void *dest, const void *src, size_t n);
342
343/**
344 * os_memmove - Copy memory area
345 * @dest: Destination
346 * @src: Source
347 * @n: Number of bytes to copy
348 * Returns: dest
349 *
350 * The memory areas src and dst may overlap.
351 */
352void * os_memmove(void *dest, const void *src, size_t n);
353
354/**
355 * os_memset - Fill memory with a constant byte
356 * @s: Memory area to be filled
357 * @c: Constant byte
358 * @n: Number of bytes started from s to fill with c
359 * Returns: s
360 */
361void * os_memset(void *s, int c, size_t n);
362
363/**
364 * os_memcmp - Compare memory areas
365 * @s1: First buffer
366 * @s2: Second buffer
367 * @n: Maximum numbers of octets to compare
368 * Returns: An integer less than, equal to, or greater than zero if s1 is
369 * found to be less than, to match, or be greater than s2. Only first n
370 * characters will be compared.
371 */
372int os_memcmp(const void *s1, const void *s2, size_t n);
373
374/**
375 * os_strdup - Duplicate a string
376 * @s: Source string
377 * Returns: Allocated buffer with the string copied into it or %NULL on failure
378 *
379 * Caller is responsible for freeing the returned buffer with os_free().
380 */
381char * os_strdup(const char *s);
382
383/**
384 * os_strlen - Calculate the length of a string
385 * @s: '\0' terminated string
386 * Returns: Number of characters in s (not counting the '\0' terminator)
387 */
388size_t os_strlen(const char *s);
389
390/**
391 * os_strcasecmp - Compare two strings ignoring case
392 * @s1: First string
393 * @s2: Second string
394 * Returns: An integer less than, equal to, or greater than zero if s1 is
395 * found to be less than, to match, or be greatred than s2
396 */
397int os_strcasecmp(const char *s1, const char *s2);
398
399/**
400 * os_strncasecmp - Compare two strings ignoring case
401 * @s1: First string
402 * @s2: Second string
403 * @n: Maximum numbers of characters to compare
404 * Returns: An integer less than, equal to, or greater than zero if s1 is
405 * found to be less than, to match, or be greater than s2. Only first n
406 * characters will be compared.
407 */
408int os_strncasecmp(const char *s1, const char *s2, size_t n);
409
410/**
411 * os_strchr - Locate the first 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 */
416char * os_strchr(const char *s, int c);
417
418/**
419 * os_strrchr - Locate the last occurrence of a character in string
420 * @s: String
421 * @c: Character to search for
422 * Returns: Pointer to the matched character or %NULL if not found
423 */
424char * os_strrchr(const char *s, int c);
425
426/**
427 * os_strcmp - Compare two strings
428 * @s1: First string
429 * @s2: Second string
430 * Returns: An integer less than, equal to, or greater than zero if s1 is
431 * found to be less than, to match, or be greatred than s2
432 */
433int os_strcmp(const char *s1, const char *s2);
434
435/**
436 * os_strncmp - Compare two strings
437 * @s1: First string
438 * @s2: Second string
439 * @n: Maximum numbers of characters to compare
440 * Returns: An integer less than, equal to, or greater than zero if s1 is
441 * found to be less than, to match, or be greater than s2. Only first n
442 * characters will be compared.
443 */
444int os_strncmp(const char *s1, const char *s2, size_t n);
445
446/**
447 * os_strstr - Locate a substring
448 * @haystack: String (haystack) to search from
449 * @needle: Needle to search from haystack
450 * Returns: Pointer to the beginning of the substring or %NULL if not found
451 */
452char * os_strstr(const char *haystack, const char *needle);
453
454/**
455 * os_snprintf - Print to a memory buffer
456 * @str: Memory buffer to print into
457 * @size: Maximum length of the str buffer
458 * @format: printf format
459 * Returns: Number of characters printed (not including trailing '\0').
460 *
461 * If the output buffer is truncated, number of characters which would have
462 * been written is returned. Since some C libraries return -1 in such a case,
463 * the caller must be prepared on that value, too, to indicate truncation.
464 *
465 * Note: Some C library implementations of snprintf() may not guarantee null
466 * termination in case the output is truncated. The OS wrapper function of
467 * os_snprintf() should provide this guarantee, i.e., to null terminate the
468 * output buffer if a C library version of the function is used and if that
469 * function does not guarantee null termination.
470 *
471 * If the target system does not include snprintf(), see, e.g.,
472 * http://www.ijs.si/software/snprintf/ for an example of a portable
473 * implementation of snprintf.
474 */
475int os_snprintf(char *str, size_t size, const char *format, ...);
476
477#else /* OS_NO_C_LIB_DEFINES */
478
479#ifdef WPA_TRACE
480void * os_malloc(size_t size);
481void * os_realloc(void *ptr, size_t size);
482void os_free(void *ptr);
483char * os_strdup(const char *s);
484#else /* WPA_TRACE */
485#ifndef os_malloc
486#define os_malloc(s) malloc((s))
487#endif
488#ifndef os_realloc
489#define os_realloc(p, s) realloc((p), (s))
490#endif
491#ifndef os_free
492#define os_free(p) free((p))
493#endif
494#ifndef os_strdup
495#ifdef _MSC_VER
496#define os_strdup(s) _strdup(s)
497#else
498#define os_strdup(s) strdup(s)
499#endif
500#endif
501#endif /* WPA_TRACE */
502
503#ifndef os_memcpy
504#define os_memcpy(d, s, n) memcpy((d), (s), (n))
505#endif
506#ifndef os_memmove
507#define os_memmove(d, s, n) memmove((d), (s), (n))
508#endif
509#ifndef os_memset
510#define os_memset(s, c, n) memset(s, c, n)
511#endif
512#ifndef os_memcmp
513#define os_memcmp(s1, s2, n) memcmp((s1), (s2), (n))
514#endif
515
516#ifndef os_strlen
517#define os_strlen(s) strlen(s)
518#endif
519#ifndef os_strcasecmp
520#ifdef _MSC_VER
521#define os_strcasecmp(s1, s2) _stricmp((s1), (s2))
522#else
523#define os_strcasecmp(s1, s2) strcasecmp((s1), (s2))
524#endif
525#endif
526#ifndef os_strncasecmp
527#ifdef _MSC_VER
528#define os_strncasecmp(s1, s2, n) _strnicmp((s1), (s2), (n))
529#else
530#define os_strncasecmp(s1, s2, n) strncasecmp((s1), (s2), (n))
531#endif
532#endif
533#ifndef os_strchr
534#define os_strchr(s, c) strchr((s), (c))
535#endif
536#ifndef os_strcmp
537#define os_strcmp(s1, s2) strcmp((s1), (s2))
538#endif
539#ifndef os_strncmp
540#define os_strncmp(s1, s2, n) strncmp((s1), (s2), (n))
541#endif
542#ifndef os_strrchr
543#define os_strrchr(s, c) strrchr((s), (c))
544#endif
545#ifndef os_strstr
546#define os_strstr(h, n) strstr((h), (n))
547#endif
548
549#ifndef os_snprintf
550#ifdef _MSC_VER
551#define os_snprintf _snprintf
552#else
553#define os_snprintf snprintf
554#endif
555#endif
556
557#endif /* OS_NO_C_LIB_DEFINES */
558
559
560static inline int os_snprintf_error(size_t size, int res)
561{
562	return res < 0 || (unsigned int) res >= size;
563}
564
565
566static inline void * os_realloc_array(void *ptr, size_t nmemb, size_t size)
567{
568	if (size && nmemb > (~(size_t) 0) / size)
569		return NULL;
570	return os_realloc(ptr, nmemb * size);
571}
572
573/**
574 * os_remove_in_array - Remove a member from an array by index
575 * @ptr: Pointer to the array
576 * @nmemb: Current member count of the array
577 * @size: The size per member of the array
578 * @idx: Index of the member to be removed
579 */
580static inline void os_remove_in_array(void *ptr, size_t nmemb, size_t size,
581				      size_t idx)
582{
583	if (idx < nmemb - 1)
584		os_memmove(((unsigned char *) ptr) + idx * size,
585			   ((unsigned char *) ptr) + (idx + 1) * size,
586			   (nmemb - idx - 1) * size);
587}
588
589/**
590 * os_strlcpy - Copy a string with size bound and NUL-termination
591 * @dest: Destination
592 * @src: Source
593 * @siz: Size of the target buffer
594 * Returns: Total length of the target string (length of src) (not including
595 * NUL-termination)
596 *
597 * This function matches in behavior with the strlcpy(3) function in OpenBSD.
598 */
599size_t os_strlcpy(char *dest, const char *src, size_t siz);
600
601/**
602 * os_memcmp_const - Constant time memory comparison
603 * @a: First buffer to compare
604 * @b: Second buffer to compare
605 * @len: Number of octets to compare
606 * Returns: 0 if buffers are equal, non-zero if not
607 *
608 * This function is meant for comparing passwords or hash values where
609 * difference in execution time could provide external observer information
610 * about the location of the difference in the memory buffers. The return value
611 * does not behave like os_memcmp(), i.e., os_memcmp_const() cannot be used to
612 * sort items into a defined order. Unlike os_memcmp(), execution time of
613 * os_memcmp_const() does not depend on the contents of the compared memory
614 * buffers, but only on the total compared length.
615 */
616int os_memcmp_const(const void *a, const void *b, size_t len);
617
618
619/**
620 * os_memdup - Allocate duplicate of passed memory chunk
621 * @src: Source buffer to duplicate
622 * @len: Length of source buffer
623 * Returns: %NULL if allocation failed, copy of src buffer otherwise
624 *
625 * This function allocates a memory block like os_malloc() would, and
626 * copies the given source buffer into it.
627 */
628void * os_memdup(const void *src, size_t len);
629
630/**
631 * os_exec - Execute an external program
632 * @program: Path to the program
633 * @arg: Command line argument string
634 * @wait_completion: Whether to wait until the program execution completes
635 * Returns: 0 on success, -1 on error
636 */
637int os_exec(const char *program, const char *arg, int wait_completion);
638
639
640#ifdef OS_REJECT_C_LIB_FUNCTIONS
641#define malloc OS_DO_NOT_USE_malloc
642#define realloc OS_DO_NOT_USE_realloc
643#define free OS_DO_NOT_USE_free
644#define memcpy OS_DO_NOT_USE_memcpy
645#define memmove OS_DO_NOT_USE_memmove
646#define memset OS_DO_NOT_USE_memset
647#define memcmp OS_DO_NOT_USE_memcmp
648#undef strdup
649#define strdup OS_DO_NOT_USE_strdup
650#define strlen OS_DO_NOT_USE_strlen
651#define strcasecmp OS_DO_NOT_USE_strcasecmp
652#define strncasecmp OS_DO_NOT_USE_strncasecmp
653#undef strchr
654#define strchr OS_DO_NOT_USE_strchr
655#undef strcmp
656#define strcmp OS_DO_NOT_USE_strcmp
657#undef strncmp
658#define strncmp OS_DO_NOT_USE_strncmp
659#undef strncpy
660#define strncpy OS_DO_NOT_USE_strncpy
661#define strrchr OS_DO_NOT_USE_strrchr
662#define strstr OS_DO_NOT_USE_strstr
663#undef snprintf
664#define snprintf OS_DO_NOT_USE_snprintf
665
666#define strcpy OS_DO_NOT_USE_strcpy
667#endif /* OS_REJECT_C_LIB_FUNCTIONS */
668
669
670#if defined(WPA_TRACE_BFD) && defined(CONFIG_TESTING_OPTIONS)
671#define TEST_FAIL() testing_test_fail()
672int testing_test_fail(void);
673extern char wpa_trace_fail_func[256];
674extern unsigned int wpa_trace_fail_after;
675extern char wpa_trace_test_fail_func[256];
676extern unsigned int wpa_trace_test_fail_after;
677#else
678#define TEST_FAIL() 0
679#endif
680
681#endif /* OS_H */
682