blob: d586e6af5e5a69fc5c6bc8d3005dfc85a403304f [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001// SPDX-License-Identifier: GPL-2.0
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -07002/*
3 * Convert integer string representation to an integer.
4 * If an integer doesn't fit into specified type, -E is returned.
5 *
6 * Integer starts with optional sign.
7 * kstrtou*() functions do not accept sign "-".
8 *
9 * Radix 0 means autodetection: leading "0x" implies radix 16,
10 * leading "0" implies radix 8, otherwise radix is 10.
11 * Autodetection hints work after optional sign, but not before.
12 *
13 * If -E is returned, result is not touched.
14 */
15#include <linux/ctype.h>
16#include <linux/errno.h>
Paul Gortmaker8bc3bcc2011-11-16 21:29:17 -050017#include <linux/export.h>
Andy Shevchenko4c527292021-06-30 18:56:10 -070018#include <linux/kstrtox.h>
19#include <linux/math64.h>
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070020#include <linux/types.h>
Linus Torvalds7c0f6ba2016-12-24 11:46:01 -080021#include <linux/uaccess.h>
Andy Shevchenko4c527292021-06-30 18:56:10 -070022
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070023#include "kstrtox.h"
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070024
Alexey Dobriyan70ac6992022-01-19 18:08:53 -080025noinline
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070026const char *_parse_integer_fixup_radix(const char *s, unsigned int *base)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070027{
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070028 if (*base == 0) {
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070029 if (s[0] == '0') {
30 if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070031 *base = 16;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070032 else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070033 *base = 8;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070034 } else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070035 *base = 10;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070036 }
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070037 if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070038 s += 2;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070039 return s;
40}
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070041
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070042/*
43 * Convert non-negative integer string representation in explicitly given radix
Richard Fitzgerald900fdc42021-05-14 17:12:04 +010044 * to an integer. A maximum of max_chars characters will be converted.
45 *
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070046 * Return number of characters consumed maybe or-ed with overflow bit.
47 * If overflow occurs, result integer (incorrect) is still returned.
48 *
49 * Don't you dare use this function.
50 */
Alexey Dobriyan70ac6992022-01-19 18:08:53 -080051noinline
Richard Fitzgerald900fdc42021-05-14 17:12:04 +010052unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned long long *p,
53 size_t max_chars)
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070054{
David Howells690d1372012-02-09 15:48:20 +000055 unsigned long long res;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070056 unsigned int rv;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070057
David Howells690d1372012-02-09 15:48:20 +000058 res = 0;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070059 rv = 0;
Richard Fitzgerald900fdc42021-05-14 17:12:04 +010060 while (max_chars--) {
Alexey Dobriyanbe5f3c72017-07-10 15:51:41 -070061 unsigned int c = *s;
Andy Shevchenko3d0b7132023-08-17 17:59:19 +030062 unsigned int lc = _tolower(c);
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070063 unsigned int val;
64
Alexey Dobriyanbe5f3c72017-07-10 15:51:41 -070065 if ('0' <= c && c <= '9')
66 val = c - '0';
67 else if ('a' <= lc && lc <= 'f')
68 val = lc - 'a' + 10;
Alexey Dobriyan78be9592011-04-14 15:22:02 -070069 else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070070 break;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070071
72 if (val >= base)
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070073 break;
David Howells690d1372012-02-09 15:48:20 +000074 /*
75 * Check for overflow only if we are within range of
76 * it in the max base we support (16)
77 */
78 if (unlikely(res & (~0ull << 60))) {
79 if (res > div_u64(ULLONG_MAX - val, base))
Alexey Dobriyan8cfd56d2016-10-11 13:51:32 -070080 rv |= KSTRTOX_OVERFLOW;
David Howells690d1372012-02-09 15:48:20 +000081 }
82 res = res * base + val;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070083 rv++;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070084 s++;
85 }
David Howells690d1372012-02-09 15:48:20 +000086 *p = res;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070087 return rv;
88}
89
Alexey Dobriyan70ac6992022-01-19 18:08:53 -080090noinline
Richard Fitzgerald900fdc42021-05-14 17:12:04 +010091unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p)
92{
93 return _parse_integer_limit(s, base, p, INT_MAX);
94}
95
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070096static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
97{
98 unsigned long long _res;
99 unsigned int rv;
100
101 s = _parse_integer_fixup_radix(s, &base);
102 rv = _parse_integer(s, base, &_res);
103 if (rv & KSTRTOX_OVERFLOW)
104 return -ERANGE;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -0700105 if (rv == 0)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700106 return -EINVAL;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -0700107 s += rv;
108 if (*s == '\n')
109 s++;
110 if (*s)
111 return -EINVAL;
112 *res = _res;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700113 return 0;
114}
115
Eldad Zack4c925d62012-12-17 16:03:04 -0800116/**
117 * kstrtoull - convert a string to an unsigned long long
118 * @s: The start of the string. The string must be null-terminated, and may also
119 * include a single newline before its terminating null. The first character
120 * may also be a plus sign, but not a minus sign.
121 * @base: The number base to use. The maximum supported base is 16. If base is
122 * given as 0, then the base of the string is automatically detected with the
123 * conventional semantics - If it begins with 0x the number will be parsed as a
124 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
125 * parsed as an octal number. Otherwise it will be parsed as a decimal.
126 * @res: Where to write the result of the conversion on success.
127 *
128 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
Kars Mulderef0f2682020-08-11 18:34:56 -0700129 * Preferred over simple_strtoull(). Return code must be checked.
Eldad Zack4c925d62012-12-17 16:03:04 -0800130 */
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800131noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700132int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
133{
134 if (s[0] == '+')
135 s++;
136 return _kstrtoull(s, base, res);
137}
138EXPORT_SYMBOL(kstrtoull);
139
Eldad Zack4c925d62012-12-17 16:03:04 -0800140/**
141 * kstrtoll - convert a string to a long long
142 * @s: The start of the string. The string must be null-terminated, and may also
143 * include a single newline before its terminating null. The first character
144 * may also be a plus sign or a minus sign.
145 * @base: The number base to use. The maximum supported base is 16. If base is
146 * given as 0, then the base of the string is automatically detected with the
147 * conventional semantics - If it begins with 0x the number will be parsed as a
148 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
149 * parsed as an octal number. Otherwise it will be parsed as a decimal.
150 * @res: Where to write the result of the conversion on success.
151 *
152 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
Kars Mulderef0f2682020-08-11 18:34:56 -0700153 * Preferred over simple_strtoll(). Return code must be checked.
Eldad Zack4c925d62012-12-17 16:03:04 -0800154 */
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800155noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700156int kstrtoll(const char *s, unsigned int base, long long *res)
157{
158 unsigned long long tmp;
159 int rv;
160
161 if (s[0] == '-') {
162 rv = _kstrtoull(s + 1, base, &tmp);
163 if (rv < 0)
164 return rv;
Alexey Dobriyan2d2e4712015-09-09 15:36:17 -0700165 if ((long long)-tmp > 0)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700166 return -ERANGE;
167 *res = -tmp;
168 } else {
169 rv = kstrtoull(s, base, &tmp);
170 if (rv < 0)
171 return rv;
172 if ((long long)tmp < 0)
173 return -ERANGE;
174 *res = tmp;
175 }
176 return 0;
177}
178EXPORT_SYMBOL(kstrtoll);
179
180/* Internal, do not use. */
181int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
182{
183 unsigned long long tmp;
184 int rv;
185
186 rv = kstrtoull(s, base, &tmp);
187 if (rv < 0)
188 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700189 if (tmp != (unsigned long)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700190 return -ERANGE;
191 *res = tmp;
192 return 0;
193}
194EXPORT_SYMBOL(_kstrtoul);
195
196/* Internal, do not use. */
197int _kstrtol(const char *s, unsigned int base, long *res)
198{
199 long long tmp;
200 int rv;
201
202 rv = kstrtoll(s, base, &tmp);
203 if (rv < 0)
204 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700205 if (tmp != (long)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700206 return -ERANGE;
207 *res = tmp;
208 return 0;
209}
210EXPORT_SYMBOL(_kstrtol);
211
Eldad Zack4c925d62012-12-17 16:03:04 -0800212/**
213 * kstrtouint - convert a string to an unsigned int
214 * @s: The start of the string. The string must be null-terminated, and may also
215 * include a single newline before its terminating null. The first character
216 * may also be a plus sign, but not a minus sign.
217 * @base: The number base to use. The maximum supported base is 16. If base is
218 * given as 0, then the base of the string is automatically detected with the
219 * conventional semantics - If it begins with 0x the number will be parsed as a
220 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
221 * parsed as an octal number. Otherwise it will be parsed as a decimal.
222 * @res: Where to write the result of the conversion on success.
223 *
224 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
Kars Mulderef0f2682020-08-11 18:34:56 -0700225 * Preferred over simple_strtoul(). Return code must be checked.
Eldad Zack4c925d62012-12-17 16:03:04 -0800226 */
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800227noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700228int kstrtouint(const char *s, unsigned int base, unsigned int *res)
229{
230 unsigned long long tmp;
231 int rv;
232
233 rv = kstrtoull(s, base, &tmp);
234 if (rv < 0)
235 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700236 if (tmp != (unsigned int)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700237 return -ERANGE;
238 *res = tmp;
239 return 0;
240}
241EXPORT_SYMBOL(kstrtouint);
242
Eldad Zack4c925d62012-12-17 16:03:04 -0800243/**
244 * kstrtoint - convert a string to an int
245 * @s: The start of the string. The string must be null-terminated, and may also
246 * include a single newline before its terminating null. The first character
247 * may also be a plus sign or a minus sign.
248 * @base: The number base to use. The maximum supported base is 16. If base is
249 * given as 0, then the base of the string is automatically detected with the
250 * conventional semantics - If it begins with 0x the number will be parsed as a
251 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
252 * parsed as an octal number. Otherwise it will be parsed as a decimal.
253 * @res: Where to write the result of the conversion on success.
254 *
255 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
Kars Mulderef0f2682020-08-11 18:34:56 -0700256 * Preferred over simple_strtol(). Return code must be checked.
Eldad Zack4c925d62012-12-17 16:03:04 -0800257 */
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800258noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700259int kstrtoint(const char *s, unsigned int base, int *res)
260{
261 long long tmp;
262 int rv;
263
264 rv = kstrtoll(s, base, &tmp);
265 if (rv < 0)
266 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700267 if (tmp != (int)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700268 return -ERANGE;
269 *res = tmp;
270 return 0;
271}
272EXPORT_SYMBOL(kstrtoint);
273
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800274noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700275int kstrtou16(const char *s, unsigned int base, u16 *res)
276{
277 unsigned long long tmp;
278 int rv;
279
280 rv = kstrtoull(s, base, &tmp);
281 if (rv < 0)
282 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700283 if (tmp != (u16)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700284 return -ERANGE;
285 *res = tmp;
286 return 0;
287}
288EXPORT_SYMBOL(kstrtou16);
289
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800290noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700291int kstrtos16(const char *s, unsigned int base, s16 *res)
292{
293 long long tmp;
294 int rv;
295
296 rv = kstrtoll(s, base, &tmp);
297 if (rv < 0)
298 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700299 if (tmp != (s16)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700300 return -ERANGE;
301 *res = tmp;
302 return 0;
303}
304EXPORT_SYMBOL(kstrtos16);
305
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800306noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700307int kstrtou8(const char *s, unsigned int base, u8 *res)
308{
309 unsigned long long tmp;
310 int rv;
311
312 rv = kstrtoull(s, base, &tmp);
313 if (rv < 0)
314 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700315 if (tmp != (u8)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700316 return -ERANGE;
317 *res = tmp;
318 return 0;
319}
320EXPORT_SYMBOL(kstrtou8);
321
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800322noinline
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700323int kstrtos8(const char *s, unsigned int base, s8 *res)
324{
325 long long tmp;
326 int rv;
327
328 rv = kstrtoll(s, base, &tmp);
329 if (rv < 0)
330 return rv;
Alexey Dobriyan048e5132018-10-30 15:05:46 -0700331 if (tmp != (s8)tmp)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700332 return -ERANGE;
333 *res = tmp;
334 return 0;
335}
336EXPORT_SYMBOL(kstrtos8);
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700337
Kees Cookef951592016-03-17 14:22:50 -0700338/**
339 * kstrtobool - convert common user inputs into boolean values
340 * @s: input string
341 * @res: result
342 *
Jagdish Gediya0d6ea3a2022-05-12 20:22:59 -0700343 * This routine returns 0 iff the first character is one of 'YyTt1NnFf0', or
Kees Cooka81a5a12016-03-17 14:22:57 -0700344 * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL. Value
345 * pointed to by res is updated upon finding a match.
Kees Cookef951592016-03-17 14:22:50 -0700346 */
Alexey Dobriyan70ac6992022-01-19 18:08:53 -0800347noinline
Kees Cookef951592016-03-17 14:22:50 -0700348int kstrtobool(const char *s, bool *res)
349{
350 if (!s)
351 return -EINVAL;
352
353 switch (s[0]) {
354 case 'y':
355 case 'Y':
Jagdish Gediya0d6ea3a2022-05-12 20:22:59 -0700356 case 't':
357 case 'T':
Kees Cookef951592016-03-17 14:22:50 -0700358 case '1':
359 *res = true;
360 return 0;
361 case 'n':
362 case 'N':
Jagdish Gediya0d6ea3a2022-05-12 20:22:59 -0700363 case 'f':
364 case 'F':
Kees Cookef951592016-03-17 14:22:50 -0700365 case '0':
366 *res = false;
367 return 0;
Kees Cooka81a5a12016-03-17 14:22:57 -0700368 case 'o':
369 case 'O':
370 switch (s[1]) {
371 case 'n':
372 case 'N':
373 *res = true;
374 return 0;
375 case 'f':
376 case 'F':
377 *res = false;
378 return 0;
379 default:
380 break;
381 }
Gustavo A. R. Silva36f9ff92020-11-19 07:11:44 -0600382 break;
Kees Cookef951592016-03-17 14:22:50 -0700383 default:
384 break;
385 }
386
387 return -EINVAL;
388}
389EXPORT_SYMBOL(kstrtobool);
390
391/*
392 * Since "base" would be a nonsense argument, this open-codes the
393 * _from_user helper instead of using the helper macro below.
394 */
395int kstrtobool_from_user(const char __user *s, size_t count, bool *res)
396{
397 /* Longest string needed to differentiate, newline, terminator */
398 char buf[4];
399
400 count = min(count, sizeof(buf) - 1);
401 if (copy_from_user(buf, s, count))
402 return -EFAULT;
403 buf[count] = '\0';
404 return kstrtobool(buf, res);
405}
406EXPORT_SYMBOL(kstrtobool_from_user);
407
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700408#define kstrto_from_user(f, g, type) \
409int f(const char __user *s, size_t count, unsigned int base, type *res) \
410{ \
411 /* sign, base 2 representation, newline, terminator */ \
412 char buf[1 + sizeof(type) * 8 + 1 + 1]; \
413 \
414 count = min(count, sizeof(buf) - 1); \
415 if (copy_from_user(buf, s, count)) \
416 return -EFAULT; \
417 buf[count] = '\0'; \
418 return g(buf, base, res); \
419} \
420EXPORT_SYMBOL(f)
421
422kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
423kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
424kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
425kstrto_from_user(kstrtol_from_user, kstrtol, long);
426kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
427kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
428kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
429kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
430kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
431kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);