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1/*
2 * Convert integer string representation to an integer.
3 * If an integer doesn't fit into specified type, -E is returned.
4 *
5 * Integer starts with optional sign.
6 * kstrtou*() functions do not accept sign "-".
7 *
8 * Radix 0 means autodetection: leading "0x" implies radix 16,
9 * leading "0" implies radix 8, otherwise radix is 10.
10 * Autodetection hints work after optional sign, but not before.
11 *
12 * If -E is returned, result is not touched.
13 */
14#include <linux/ctype.h>
15#include <linux/errno.h>
16#include <linux/kernel.h>
17#include <linux/math64.h>
18#include <linux/export.h>
19#include <linux/types.h>
20#include <asm/uaccess.h>
21#include "kstrtox.h"
22
23const char *_parse_integer_fixup_radix(const char *s, unsigned int *base)
24{
25 if (*base == 0) {
26 if (s[0] == '0') {
27 if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
28 *base = 16;
29 else
30 *base = 8;
31 } else
32 *base = 10;
33 }
34 if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
35 s += 2;
36 return s;
37}
38
39/*
40 * Convert non-negative integer string representation in explicitly given radix
41 * to an integer.
42 * Return number of characters consumed maybe or-ed with overflow bit.
43 * If overflow occurs, result integer (incorrect) is still returned.
44 *
45 * Don't you dare use this function.
46 */
47unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p)
48{
49 unsigned long long res;
50 unsigned int rv;
51 int overflow;
52
53 res = 0;
54 rv = 0;
55 overflow = 0;
56 while (*s) {
57 unsigned int val;
58
59 if ('0' <= *s && *s <= '9')
60 val = *s - '0';
61 else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
62 val = _tolower(*s) - 'a' + 10;
63 else
64 break;
65
66 if (val >= base)
67 break;
68 /*
69 * Check for overflow only if we are within range of
70 * it in the max base we support (16)
71 */
72 if (unlikely(res & (~0ull << 60))) {
73 if (res > div_u64(ULLONG_MAX - val, base))
74 overflow = 1;
75 }
76 res = res * base + val;
77 rv++;
78 s++;
79 }
80 *p = res;
81 if (overflow)
82 rv |= KSTRTOX_OVERFLOW;
83 return rv;
84}
85
86static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
87{
88 unsigned long long _res;
89 unsigned int rv;
90
91 s = _parse_integer_fixup_radix(s, &base);
92 rv = _parse_integer(s, base, &_res);
93 if (rv & KSTRTOX_OVERFLOW)
94 return -ERANGE;
95 if (rv == 0)
96 return -EINVAL;
97 s += rv;
98 if (*s == '\n')
99 s++;
100 if (*s)
101 return -EINVAL;
102 *res = _res;
103 return 0;
104}
105
106/**
107 * kstrtoull - convert a string to an unsigned long long
108 * @s: The start of the string. The string must be null-terminated, and may also
109 * include a single newline before its terminating null. The first character
110 * may also be a plus sign, but not a minus sign.
111 * @base: The number base to use. The maximum supported base is 16. If base is
112 * given as 0, then the base of the string is automatically detected with the
113 * conventional semantics - If it begins with 0x the number will be parsed as a
114 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
115 * parsed as an octal number. Otherwise it will be parsed as a decimal.
116 * @res: Where to write the result of the conversion on success.
117 *
118 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
119 * Used as a replacement for the obsolete simple_strtoull. Return code must
120 * be checked.
121 */
122int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
123{
124 if (s[0] == '+')
125 s++;
126 return _kstrtoull(s, base, res);
127}
128EXPORT_SYMBOL(kstrtoull);
129
130/**
131 * kstrtoll - convert a string to a long long
132 * @s: The start of the string. The string must be null-terminated, and may also
133 * include a single newline before its terminating null. The first character
134 * may also be a plus sign or a minus sign.
135 * @base: The number base to use. The maximum supported base is 16. If base is
136 * given as 0, then the base of the string is automatically detected with the
137 * conventional semantics - If it begins with 0x the number will be parsed as a
138 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
139 * parsed as an octal number. Otherwise it will be parsed as a decimal.
140 * @res: Where to write the result of the conversion on success.
141 *
142 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
143 * Used as a replacement for the obsolete simple_strtoull. Return code must
144 * be checked.
145 */
146int kstrtoll(const char *s, unsigned int base, long long *res)
147{
148 unsigned long long tmp;
149 int rv;
150
151 if (s[0] == '-') {
152 rv = _kstrtoull(s + 1, base, &tmp);
153 if (rv < 0)
154 return rv;
155 if ((long long)(-tmp) >= 0)
156 return -ERANGE;
157 *res = -tmp;
158 } else {
159 rv = kstrtoull(s, base, &tmp);
160 if (rv < 0)
161 return rv;
162 if ((long long)tmp < 0)
163 return -ERANGE;
164 *res = tmp;
165 }
166 return 0;
167}
168EXPORT_SYMBOL(kstrtoll);
169
170/* Internal, do not use. */
171int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
172{
173 unsigned long long tmp;
174 int rv;
175
176 rv = kstrtoull(s, base, &tmp);
177 if (rv < 0)
178 return rv;
179 if (tmp != (unsigned long long)(unsigned long)tmp)
180 return -ERANGE;
181 *res = tmp;
182 return 0;
183}
184EXPORT_SYMBOL(_kstrtoul);
185
186/* Internal, do not use. */
187int _kstrtol(const char *s, unsigned int base, long *res)
188{
189 long long tmp;
190 int rv;
191
192 rv = kstrtoll(s, base, &tmp);
193 if (rv < 0)
194 return rv;
195 if (tmp != (long long)(long)tmp)
196 return -ERANGE;
197 *res = tmp;
198 return 0;
199}
200EXPORT_SYMBOL(_kstrtol);
201
202/**
203 * kstrtouint - convert a string to an unsigned int
204 * @s: The start of the string. The string must be null-terminated, and may also
205 * include a single newline before its terminating null. The first character
206 * may also be a plus sign, but not a minus sign.
207 * @base: The number base to use. The maximum supported base is 16. If base is
208 * given as 0, then the base of the string is automatically detected with the
209 * conventional semantics - If it begins with 0x the number will be parsed as a
210 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
211 * parsed as an octal number. Otherwise it will be parsed as a decimal.
212 * @res: Where to write the result of the conversion on success.
213 *
214 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
215 * Used as a replacement for the obsolete simple_strtoull. Return code must
216 * be checked.
217 */
218int kstrtouint(const char *s, unsigned int base, unsigned int *res)
219{
220 unsigned long long tmp;
221 int rv;
222
223 rv = kstrtoull(s, base, &tmp);
224 if (rv < 0)
225 return rv;
226 if (tmp != (unsigned long long)(unsigned int)tmp)
227 return -ERANGE;
228 *res = tmp;
229 return 0;
230}
231EXPORT_SYMBOL(kstrtouint);
232
233/**
234 * kstrtoint - convert a string to an int
235 * @s: The start of the string. The string must be null-terminated, and may also
236 * include a single newline before its terminating null. The first character
237 * may also be a plus sign or a minus sign.
238 * @base: The number base to use. The maximum supported base is 16. If base is
239 * given as 0, then the base of the string is automatically detected with the
240 * conventional semantics - If it begins with 0x the number will be parsed as a
241 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
242 * parsed as an octal number. Otherwise it will be parsed as a decimal.
243 * @res: Where to write the result of the conversion on success.
244 *
245 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
246 * Used as a replacement for the obsolete simple_strtoull. Return code must
247 * be checked.
248 */
249int kstrtoint(const char *s, unsigned int base, int *res)
250{
251 long long tmp;
252 int rv;
253
254 rv = kstrtoll(s, base, &tmp);
255 if (rv < 0)
256 return rv;
257 if (tmp != (long long)(int)tmp)
258 return -ERANGE;
259 *res = tmp;
260 return 0;
261}
262EXPORT_SYMBOL(kstrtoint);
263
264int kstrtou16(const char *s, unsigned int base, u16 *res)
265{
266 unsigned long long tmp;
267 int rv;
268
269 rv = kstrtoull(s, base, &tmp);
270 if (rv < 0)
271 return rv;
272 if (tmp != (unsigned long long)(u16)tmp)
273 return -ERANGE;
274 *res = tmp;
275 return 0;
276}
277EXPORT_SYMBOL(kstrtou16);
278
279int kstrtos16(const char *s, unsigned int base, s16 *res)
280{
281 long long tmp;
282 int rv;
283
284 rv = kstrtoll(s, base, &tmp);
285 if (rv < 0)
286 return rv;
287 if (tmp != (long long)(s16)tmp)
288 return -ERANGE;
289 *res = tmp;
290 return 0;
291}
292EXPORT_SYMBOL(kstrtos16);
293
294int kstrtou8(const char *s, unsigned int base, u8 *res)
295{
296 unsigned long long tmp;
297 int rv;
298
299 rv = kstrtoull(s, base, &tmp);
300 if (rv < 0)
301 return rv;
302 if (tmp != (unsigned long long)(u8)tmp)
303 return -ERANGE;
304 *res = tmp;
305 return 0;
306}
307EXPORT_SYMBOL(kstrtou8);
308
309int kstrtos8(const char *s, unsigned int base, s8 *res)
310{
311 long long tmp;
312 int rv;
313
314 rv = kstrtoll(s, base, &tmp);
315 if (rv < 0)
316 return rv;
317 if (tmp != (long long)(s8)tmp)
318 return -ERANGE;
319 *res = tmp;
320 return 0;
321}
322EXPORT_SYMBOL(kstrtos8);
323
324#define kstrto_from_user(f, g, type) \
325int f(const char __user *s, size_t count, unsigned int base, type *res) \
326{ \
327 /* sign, base 2 representation, newline, terminator */ \
328 char buf[1 + sizeof(type) * 8 + 1 + 1]; \
329 \
330 count = min(count, sizeof(buf) - 1); \
331 if (copy_from_user(buf, s, count)) \
332 return -EFAULT; \
333 buf[count] = '\0'; \
334 return g(buf, base, res); \
335} \
336EXPORT_SYMBOL(f)
337
338kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
339kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
340kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
341kstrto_from_user(kstrtol_from_user, kstrtol, long);
342kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
343kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
344kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
345kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
346kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
347kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);
1/*
2 * Convert integer string representation to an integer.
3 * If an integer doesn't fit into specified type, -E is returned.
4 *
5 * Integer starts with optional sign.
6 * kstrtou*() functions do not accept sign "-".
7 *
8 * Radix 0 means autodetection: leading "0x" implies radix 16,
9 * leading "0" implies radix 8, otherwise radix is 10.
10 * Autodetection hints work after optional sign, but not before.
11 *
12 * If -E is returned, result is not touched.
13 */
14#include <linux/ctype.h>
15#include <linux/errno.h>
16#include <linux/kernel.h>
17#include <linux/math64.h>
18#include <linux/module.h>
19#include <linux/types.h>
20#include <asm/uaccess.h>
21
22static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
23{
24 unsigned long long acc;
25 int ok;
26
27 if (base == 0) {
28 if (s[0] == '0') {
29 if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
30 base = 16;
31 else
32 base = 8;
33 } else
34 base = 10;
35 }
36 if (base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
37 s += 2;
38
39 acc = 0;
40 ok = 0;
41 while (*s) {
42 unsigned int val;
43
44 if ('0' <= *s && *s <= '9')
45 val = *s - '0';
46 else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
47 val = _tolower(*s) - 'a' + 10;
48 else if (*s == '\n' && *(s + 1) == '\0')
49 break;
50 else
51 return -EINVAL;
52
53 if (val >= base)
54 return -EINVAL;
55 if (acc > div_u64(ULLONG_MAX - val, base))
56 return -ERANGE;
57 acc = acc * base + val;
58 ok = 1;
59
60 s++;
61 }
62 if (!ok)
63 return -EINVAL;
64 *res = acc;
65 return 0;
66}
67
68int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
69{
70 if (s[0] == '+')
71 s++;
72 return _kstrtoull(s, base, res);
73}
74EXPORT_SYMBOL(kstrtoull);
75
76int kstrtoll(const char *s, unsigned int base, long long *res)
77{
78 unsigned long long tmp;
79 int rv;
80
81 if (s[0] == '-') {
82 rv = _kstrtoull(s + 1, base, &tmp);
83 if (rv < 0)
84 return rv;
85 if ((long long)(-tmp) >= 0)
86 return -ERANGE;
87 *res = -tmp;
88 } else {
89 rv = kstrtoull(s, base, &tmp);
90 if (rv < 0)
91 return rv;
92 if ((long long)tmp < 0)
93 return -ERANGE;
94 *res = tmp;
95 }
96 return 0;
97}
98EXPORT_SYMBOL(kstrtoll);
99
100/* Internal, do not use. */
101int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
102{
103 unsigned long long tmp;
104 int rv;
105
106 rv = kstrtoull(s, base, &tmp);
107 if (rv < 0)
108 return rv;
109 if (tmp != (unsigned long long)(unsigned long)tmp)
110 return -ERANGE;
111 *res = tmp;
112 return 0;
113}
114EXPORT_SYMBOL(_kstrtoul);
115
116/* Internal, do not use. */
117int _kstrtol(const char *s, unsigned int base, long *res)
118{
119 long long tmp;
120 int rv;
121
122 rv = kstrtoll(s, base, &tmp);
123 if (rv < 0)
124 return rv;
125 if (tmp != (long long)(long)tmp)
126 return -ERANGE;
127 *res = tmp;
128 return 0;
129}
130EXPORT_SYMBOL(_kstrtol);
131
132int kstrtouint(const char *s, unsigned int base, unsigned int *res)
133{
134 unsigned long long tmp;
135 int rv;
136
137 rv = kstrtoull(s, base, &tmp);
138 if (rv < 0)
139 return rv;
140 if (tmp != (unsigned long long)(unsigned int)tmp)
141 return -ERANGE;
142 *res = tmp;
143 return 0;
144}
145EXPORT_SYMBOL(kstrtouint);
146
147int kstrtoint(const char *s, unsigned int base, int *res)
148{
149 long long tmp;
150 int rv;
151
152 rv = kstrtoll(s, base, &tmp);
153 if (rv < 0)
154 return rv;
155 if (tmp != (long long)(int)tmp)
156 return -ERANGE;
157 *res = tmp;
158 return 0;
159}
160EXPORT_SYMBOL(kstrtoint);
161
162int kstrtou16(const char *s, unsigned int base, u16 *res)
163{
164 unsigned long long tmp;
165 int rv;
166
167 rv = kstrtoull(s, base, &tmp);
168 if (rv < 0)
169 return rv;
170 if (tmp != (unsigned long long)(u16)tmp)
171 return -ERANGE;
172 *res = tmp;
173 return 0;
174}
175EXPORT_SYMBOL(kstrtou16);
176
177int kstrtos16(const char *s, unsigned int base, s16 *res)
178{
179 long long tmp;
180 int rv;
181
182 rv = kstrtoll(s, base, &tmp);
183 if (rv < 0)
184 return rv;
185 if (tmp != (long long)(s16)tmp)
186 return -ERANGE;
187 *res = tmp;
188 return 0;
189}
190EXPORT_SYMBOL(kstrtos16);
191
192int kstrtou8(const char *s, unsigned int base, u8 *res)
193{
194 unsigned long long tmp;
195 int rv;
196
197 rv = kstrtoull(s, base, &tmp);
198 if (rv < 0)
199 return rv;
200 if (tmp != (unsigned long long)(u8)tmp)
201 return -ERANGE;
202 *res = tmp;
203 return 0;
204}
205EXPORT_SYMBOL(kstrtou8);
206
207int kstrtos8(const char *s, unsigned int base, s8 *res)
208{
209 long long tmp;
210 int rv;
211
212 rv = kstrtoll(s, base, &tmp);
213 if (rv < 0)
214 return rv;
215 if (tmp != (long long)(s8)tmp)
216 return -ERANGE;
217 *res = tmp;
218 return 0;
219}
220EXPORT_SYMBOL(kstrtos8);
221
222#define kstrto_from_user(f, g, type) \
223int f(const char __user *s, size_t count, unsigned int base, type *res) \
224{ \
225 /* sign, base 2 representation, newline, terminator */ \
226 char buf[1 + sizeof(type) * 8 + 1 + 1]; \
227 \
228 count = min(count, sizeof(buf) - 1); \
229 if (copy_from_user(buf, s, count)) \
230 return -EFAULT; \
231 buf[count] = '\0'; \
232 return g(buf, base, res); \
233} \
234EXPORT_SYMBOL(f)
235
236kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
237kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
238kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
239kstrto_from_user(kstrtol_from_user, kstrtol, long);
240kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
241kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
242kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
243kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
244kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
245kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);