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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
3c9f3681 JB |
2 | /* |
3 | * Helpers for formatting and printing strings | |
4 | * | |
5 | * Copyright 31 August 2008 James Bottomley | |
16c7fa05 | 6 | * Copyright (C) 2013, Intel Corporation |
3c9f3681 | 7 | */ |
b9f28d86 | 8 | #include <linux/bug.h> |
3c9f3681 JB |
9 | #include <linux/kernel.h> |
10 | #include <linux/math64.h> | |
8bc3bcc9 | 11 | #include <linux/export.h> |
16c7fa05 | 12 | #include <linux/ctype.h> |
acdb89b6 | 13 | #include <linux/device.h> |
c8250381 | 14 | #include <linux/errno.h> |
21985319 KC |
15 | #include <linux/fs.h> |
16 | #include <linux/limits.h> | |
0d044328 | 17 | #include <linux/mm.h> |
b53f27e4 | 18 | #include <linux/slab.h> |
c8250381 | 19 | #include <linux/string.h> |
3c9f3681 JB |
20 | #include <linux/string_helpers.h> |
21 | ||
22 | /** | |
23 | * string_get_size - get the size in the specified units | |
b9f28d86 JB |
24 | * @size: The size to be converted in blocks |
25 | * @blk_size: Size of the block (use 1 for size in bytes) | |
3c9f3681 JB |
26 | * @units: units to use (powers of 1000 or 1024) |
27 | * @buf: buffer to format to | |
28 | * @len: length of buffer | |
29 | * | |
30 | * This function returns a string formatted to 3 significant figures | |
d1214c65 RV |
31 | * giving the size in the required units. @buf should have room for |
32 | * at least 9 bytes and will always be zero terminated. | |
3c9f3681 | 33 | * |
83feeb19 KO |
34 | * Return value: number of characters of output that would have been written |
35 | * (which may be greater than len, if output was truncated). | |
3c9f3681 | 36 | */ |
83feeb19 KO |
37 | int string_get_size(u64 size, u64 blk_size, const enum string_size_units units, |
38 | char *buf, int len) | |
3c9f3681 | 39 | { |
142cda5d | 40 | static const char *const units_10[] = { |
b9f28d86 | 41 | "B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" |
142cda5d MK |
42 | }; |
43 | static const char *const units_2[] = { | |
b9f28d86 | 44 | "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB" |
142cda5d MK |
45 | }; |
46 | static const char *const *const units_str[] = { | |
47 | [STRING_UNITS_10] = units_10, | |
3c9f3681 JB |
48 | [STRING_UNITS_2] = units_2, |
49 | }; | |
68aecfb9 | 50 | static const unsigned int divisor[] = { |
3c9f3681 JB |
51 | [STRING_UNITS_10] = 1000, |
52 | [STRING_UNITS_2] = 1024, | |
53 | }; | |
564b026f JB |
54 | static const unsigned int rounding[] = { 500, 50, 5 }; |
55 | int i = 0, j; | |
56 | u32 remainder = 0, sf_cap; | |
3c9f3681 | 57 | char tmp[8]; |
b9f28d86 | 58 | const char *unit; |
3c9f3681 JB |
59 | |
60 | tmp[0] = '\0'; | |
564b026f JB |
61 | |
62 | if (blk_size == 0) | |
63 | size = 0; | |
64 | if (size == 0) | |
b9f28d86 | 65 | goto out; |
3c9f3681 | 66 | |
564b026f JB |
67 | /* This is Napier's algorithm. Reduce the original block size to |
68 | * | |
69 | * coefficient * divisor[units]^i | |
70 | * | |
71 | * we do the reduction so both coefficients are just under 32 bits so | |
72 | * that multiplying them together won't overflow 64 bits and we keep | |
73 | * as much precision as possible in the numbers. | |
74 | * | |
75 | * Note: it's safe to throw away the remainders here because all the | |
76 | * precision is in the coefficients. | |
77 | */ | |
78 | while (blk_size >> 32) { | |
79 | do_div(blk_size, divisor[units]); | |
b9f28d86 JB |
80 | i++; |
81 | } | |
82 | ||
564b026f JB |
83 | while (size >> 32) { |
84 | do_div(size, divisor[units]); | |
b9f28d86 | 85 | i++; |
b9f28d86 JB |
86 | } |
87 | ||
564b026f JB |
88 | /* now perform the actual multiplication keeping i as the sum of the |
89 | * two logarithms */ | |
b9f28d86 | 90 | size *= blk_size; |
3c9f3681 | 91 | |
564b026f | 92 | /* and logarithmically reduce it until it's just under the divisor */ |
b9f28d86 JB |
93 | while (size >= divisor[units]) { |
94 | remainder = do_div(size, divisor[units]); | |
95 | i++; | |
3c9f3681 JB |
96 | } |
97 | ||
564b026f JB |
98 | /* work out in j how many digits of precision we need from the |
99 | * remainder */ | |
b9f28d86 JB |
100 | sf_cap = size; |
101 | for (j = 0; sf_cap*10 < 1000; j++) | |
102 | sf_cap *= 10; | |
103 | ||
564b026f JB |
104 | if (units == STRING_UNITS_2) { |
105 | /* express the remainder as a decimal. It's currently the | |
106 | * numerator of a fraction whose denominator is | |
107 | * divisor[units], which is 1 << 10 for STRING_UNITS_2 */ | |
b9f28d86 | 108 | remainder *= 1000; |
564b026f JB |
109 | remainder >>= 10; |
110 | } | |
111 | ||
112 | /* add a 5 to the digit below what will be printed to ensure | |
113 | * an arithmetical round up and carry it through to size */ | |
114 | remainder += rounding[j]; | |
115 | if (remainder >= 1000) { | |
116 | remainder -= 1000; | |
117 | size += 1; | |
118 | } | |
119 | ||
120 | if (j) { | |
b9f28d86 JB |
121 | snprintf(tmp, sizeof(tmp), ".%03u", remainder); |
122 | tmp[j+1] = '\0'; | |
123 | } | |
124 | ||
125 | out: | |
126 | if (i >= ARRAY_SIZE(units_2)) | |
127 | unit = "UNK"; | |
128 | else | |
129 | unit = units_str[units][i]; | |
130 | ||
83feeb19 KO |
131 | return snprintf(buf, len, "%u%s %s", (u32)size, |
132 | tmp, unit); | |
3c9f3681 JB |
133 | } |
134 | EXPORT_SYMBOL(string_get_size); | |
16c7fa05 | 135 | |
f0b93323 CR |
136 | /** |
137 | * parse_int_array_user - Split string into a sequence of integers | |
138 | * @from: The user space buffer to read from | |
139 | * @count: The maximum number of bytes to read | |
140 | * @array: Returned pointer to sequence of integers | |
141 | * | |
142 | * On success @array is allocated and initialized with a sequence of | |
143 | * integers extracted from the @from plus an additional element that | |
144 | * begins the sequence and specifies the integers count. | |
145 | * | |
146 | * Caller takes responsibility for freeing @array when it is no longer | |
147 | * needed. | |
148 | */ | |
149 | int parse_int_array_user(const char __user *from, size_t count, int **array) | |
150 | { | |
151 | int *ints, nints; | |
152 | char *buf; | |
153 | int ret = 0; | |
154 | ||
155 | buf = memdup_user_nul(from, count); | |
156 | if (IS_ERR(buf)) | |
157 | return PTR_ERR(buf); | |
158 | ||
159 | get_options(buf, 0, &nints); | |
160 | if (!nints) { | |
161 | ret = -ENOENT; | |
162 | goto free_buf; | |
163 | } | |
164 | ||
165 | ints = kcalloc(nints + 1, sizeof(*ints), GFP_KERNEL); | |
166 | if (!ints) { | |
167 | ret = -ENOMEM; | |
168 | goto free_buf; | |
169 | } | |
170 | ||
171 | get_options(buf, nints + 1, ints); | |
172 | *array = ints; | |
173 | ||
174 | free_buf: | |
175 | kfree(buf); | |
176 | return ret; | |
177 | } | |
178 | EXPORT_SYMBOL(parse_int_array_user); | |
179 | ||
16c7fa05 AS |
180 | static bool unescape_space(char **src, char **dst) |
181 | { | |
182 | char *p = *dst, *q = *src; | |
183 | ||
184 | switch (*q) { | |
185 | case 'n': | |
186 | *p = '\n'; | |
187 | break; | |
188 | case 'r': | |
189 | *p = '\r'; | |
190 | break; | |
191 | case 't': | |
192 | *p = '\t'; | |
193 | break; | |
194 | case 'v': | |
195 | *p = '\v'; | |
196 | break; | |
197 | case 'f': | |
198 | *p = '\f'; | |
199 | break; | |
200 | default: | |
201 | return false; | |
202 | } | |
203 | *dst += 1; | |
204 | *src += 1; | |
205 | return true; | |
206 | } | |
207 | ||
208 | static bool unescape_octal(char **src, char **dst) | |
209 | { | |
210 | char *p = *dst, *q = *src; | |
211 | u8 num; | |
212 | ||
213 | if (isodigit(*q) == 0) | |
214 | return false; | |
215 | ||
216 | num = (*q++) & 7; | |
217 | while (num < 32 && isodigit(*q) && (q - *src < 3)) { | |
218 | num <<= 3; | |
219 | num += (*q++) & 7; | |
220 | } | |
221 | *p = num; | |
222 | *dst += 1; | |
223 | *src = q; | |
224 | return true; | |
225 | } | |
226 | ||
227 | static bool unescape_hex(char **src, char **dst) | |
228 | { | |
229 | char *p = *dst, *q = *src; | |
230 | int digit; | |
231 | u8 num; | |
232 | ||
233 | if (*q++ != 'x') | |
234 | return false; | |
235 | ||
236 | num = digit = hex_to_bin(*q++); | |
237 | if (digit < 0) | |
238 | return false; | |
239 | ||
240 | digit = hex_to_bin(*q); | |
241 | if (digit >= 0) { | |
242 | q++; | |
243 | num = (num << 4) | digit; | |
244 | } | |
245 | *p = num; | |
246 | *dst += 1; | |
247 | *src = q; | |
248 | return true; | |
249 | } | |
250 | ||
251 | static bool unescape_special(char **src, char **dst) | |
252 | { | |
253 | char *p = *dst, *q = *src; | |
254 | ||
255 | switch (*q) { | |
256 | case '\"': | |
257 | *p = '\"'; | |
258 | break; | |
259 | case '\\': | |
260 | *p = '\\'; | |
261 | break; | |
262 | case 'a': | |
263 | *p = '\a'; | |
264 | break; | |
265 | case 'e': | |
266 | *p = '\e'; | |
267 | break; | |
268 | default: | |
269 | return false; | |
270 | } | |
271 | *dst += 1; | |
272 | *src += 1; | |
273 | return true; | |
274 | } | |
275 | ||
d295634e AS |
276 | /** |
277 | * string_unescape - unquote characters in the given string | |
278 | * @src: source buffer (escaped) | |
279 | * @dst: destination buffer (unescaped) | |
280 | * @size: size of the destination buffer (0 to unlimit) | |
b4658cdd JC |
281 | * @flags: combination of the flags. |
282 | * | |
283 | * Description: | |
284 | * The function unquotes characters in the given string. | |
285 | * | |
286 | * Because the size of the output will be the same as or less than the size of | |
287 | * the input, the transformation may be performed in place. | |
288 | * | |
289 | * Caller must provide valid source and destination pointers. Be aware that | |
290 | * destination buffer will always be NULL-terminated. Source string must be | |
291 | * NULL-terminated as well. The supported flags are:: | |
292 | * | |
293 | * UNESCAPE_SPACE: | |
d295634e AS |
294 | * '\f' - form feed |
295 | * '\n' - new line | |
296 | * '\r' - carriage return | |
297 | * '\t' - horizontal tab | |
298 | * '\v' - vertical tab | |
b4658cdd | 299 | * UNESCAPE_OCTAL: |
d295634e | 300 | * '\NNN' - byte with octal value NNN (1 to 3 digits) |
b4658cdd | 301 | * UNESCAPE_HEX: |
d295634e | 302 | * '\xHH' - byte with hexadecimal value HH (1 to 2 digits) |
b4658cdd | 303 | * UNESCAPE_SPECIAL: |
d295634e AS |
304 | * '\"' - double quote |
305 | * '\\' - backslash | |
306 | * '\a' - alert (BEL) | |
307 | * '\e' - escape | |
b4658cdd | 308 | * UNESCAPE_ANY: |
d295634e AS |
309 | * all previous together |
310 | * | |
d295634e AS |
311 | * Return: |
312 | * The amount of the characters processed to the destination buffer excluding | |
313 | * trailing '\0' is returned. | |
314 | */ | |
16c7fa05 AS |
315 | int string_unescape(char *src, char *dst, size_t size, unsigned int flags) |
316 | { | |
317 | char *out = dst; | |
318 | ||
319 | while (*src && --size) { | |
320 | if (src[0] == '\\' && src[1] != '\0' && size > 1) { | |
321 | src++; | |
322 | size--; | |
323 | ||
324 | if (flags & UNESCAPE_SPACE && | |
325 | unescape_space(&src, &out)) | |
326 | continue; | |
327 | ||
328 | if (flags & UNESCAPE_OCTAL && | |
329 | unescape_octal(&src, &out)) | |
330 | continue; | |
331 | ||
332 | if (flags & UNESCAPE_HEX && | |
333 | unescape_hex(&src, &out)) | |
334 | continue; | |
335 | ||
336 | if (flags & UNESCAPE_SPECIAL && | |
337 | unescape_special(&src, &out)) | |
338 | continue; | |
339 | ||
340 | *out++ = '\\'; | |
341 | } | |
342 | *out++ = *src++; | |
343 | } | |
344 | *out = '\0'; | |
345 | ||
346 | return out - dst; | |
347 | } | |
348 | EXPORT_SYMBOL(string_unescape); | |
c8250381 | 349 | |
3aeddc7d | 350 | static bool escape_passthrough(unsigned char c, char **dst, char *end) |
c8250381 AS |
351 | { |
352 | char *out = *dst; | |
353 | ||
3aeddc7d RV |
354 | if (out < end) |
355 | *out = c; | |
356 | *dst = out + 1; | |
357 | return true; | |
c8250381 AS |
358 | } |
359 | ||
3aeddc7d | 360 | static bool escape_space(unsigned char c, char **dst, char *end) |
c8250381 AS |
361 | { |
362 | char *out = *dst; | |
363 | unsigned char to; | |
364 | ||
c8250381 AS |
365 | switch (c) { |
366 | case '\n': | |
367 | to = 'n'; | |
368 | break; | |
369 | case '\r': | |
370 | to = 'r'; | |
371 | break; | |
372 | case '\t': | |
373 | to = 't'; | |
374 | break; | |
375 | case '\v': | |
376 | to = 'v'; | |
377 | break; | |
378 | case '\f': | |
379 | to = 'f'; | |
380 | break; | |
381 | default: | |
3aeddc7d | 382 | return false; |
c8250381 AS |
383 | } |
384 | ||
3aeddc7d RV |
385 | if (out < end) |
386 | *out = '\\'; | |
387 | ++out; | |
388 | if (out < end) | |
389 | *out = to; | |
390 | ++out; | |
c8250381 | 391 | |
3aeddc7d RV |
392 | *dst = out; |
393 | return true; | |
c8250381 AS |
394 | } |
395 | ||
3aeddc7d | 396 | static bool escape_special(unsigned char c, char **dst, char *end) |
c8250381 AS |
397 | { |
398 | char *out = *dst; | |
399 | unsigned char to; | |
400 | ||
c8250381 AS |
401 | switch (c) { |
402 | case '\\': | |
403 | to = '\\'; | |
404 | break; | |
405 | case '\a': | |
406 | to = 'a'; | |
407 | break; | |
408 | case '\e': | |
409 | to = 'e'; | |
410 | break; | |
91027d0a CD |
411 | case '"': |
412 | to = '"'; | |
413 | break; | |
c8250381 | 414 | default: |
3aeddc7d | 415 | return false; |
c8250381 AS |
416 | } |
417 | ||
3aeddc7d RV |
418 | if (out < end) |
419 | *out = '\\'; | |
420 | ++out; | |
421 | if (out < end) | |
422 | *out = to; | |
423 | ++out; | |
c8250381 | 424 | |
3aeddc7d RV |
425 | *dst = out; |
426 | return true; | |
c8250381 AS |
427 | } |
428 | ||
3aeddc7d | 429 | static bool escape_null(unsigned char c, char **dst, char *end) |
c8250381 AS |
430 | { |
431 | char *out = *dst; | |
432 | ||
c8250381 | 433 | if (c) |
3aeddc7d | 434 | return false; |
c8250381 | 435 | |
3aeddc7d RV |
436 | if (out < end) |
437 | *out = '\\'; | |
438 | ++out; | |
439 | if (out < end) | |
440 | *out = '0'; | |
441 | ++out; | |
c8250381 | 442 | |
3aeddc7d RV |
443 | *dst = out; |
444 | return true; | |
c8250381 AS |
445 | } |
446 | ||
3aeddc7d | 447 | static bool escape_octal(unsigned char c, char **dst, char *end) |
c8250381 AS |
448 | { |
449 | char *out = *dst; | |
450 | ||
3aeddc7d RV |
451 | if (out < end) |
452 | *out = '\\'; | |
453 | ++out; | |
454 | if (out < end) | |
455 | *out = ((c >> 6) & 0x07) + '0'; | |
456 | ++out; | |
457 | if (out < end) | |
458 | *out = ((c >> 3) & 0x07) + '0'; | |
459 | ++out; | |
460 | if (out < end) | |
461 | *out = ((c >> 0) & 0x07) + '0'; | |
462 | ++out; | |
c8250381 AS |
463 | |
464 | *dst = out; | |
3aeddc7d | 465 | return true; |
c8250381 AS |
466 | } |
467 | ||
3aeddc7d | 468 | static bool escape_hex(unsigned char c, char **dst, char *end) |
c8250381 AS |
469 | { |
470 | char *out = *dst; | |
471 | ||
3aeddc7d RV |
472 | if (out < end) |
473 | *out = '\\'; | |
474 | ++out; | |
475 | if (out < end) | |
476 | *out = 'x'; | |
477 | ++out; | |
478 | if (out < end) | |
479 | *out = hex_asc_hi(c); | |
480 | ++out; | |
481 | if (out < end) | |
482 | *out = hex_asc_lo(c); | |
483 | ++out; | |
c8250381 AS |
484 | |
485 | *dst = out; | |
3aeddc7d | 486 | return true; |
c8250381 AS |
487 | } |
488 | ||
489 | /** | |
490 | * string_escape_mem - quote characters in the given memory buffer | |
491 | * @src: source buffer (unescaped) | |
492 | * @isz: source buffer size | |
493 | * @dst: destination buffer (escaped) | |
494 | * @osz: destination buffer size | |
b4658cdd JC |
495 | * @flags: combination of the flags |
496 | * @only: NULL-terminated string containing characters used to limit | |
497 | * the selected escape class. If characters are included in @only | |
498 | * that would not normally be escaped by the classes selected | |
499 | * in @flags, they will be copied to @dst unescaped. | |
500 | * | |
501 | * Description: | |
502 | * The process of escaping byte buffer includes several parts. They are applied | |
503 | * in the following sequence. | |
504 | * | |
62519b88 | 505 | * 1. The character is not matched to the one from @only string and thus |
b4658cdd | 506 | * must go as-is to the output. |
0362c27f | 507 | * 2. The character is matched to the printable and ASCII classes, if asked, |
a0809783 | 508 | * and in case of match it passes through to the output. |
0362c27f AS |
509 | * 3. The character is matched to the printable or ASCII class, if asked, |
510 | * and in case of match it passes through to the output. | |
511 | * 4. The character is checked if it falls into the class given by @flags. | |
b4658cdd JC |
512 | * %ESCAPE_OCTAL and %ESCAPE_HEX are going last since they cover any |
513 | * character. Note that they actually can't go together, otherwise | |
514 | * %ESCAPE_HEX will be ignored. | |
515 | * | |
516 | * Caller must provide valid source and destination pointers. Be aware that | |
517 | * destination buffer will not be NULL-terminated, thus caller have to append | |
a0809783 | 518 | * it if needs. The supported flags are:: |
b4658cdd | 519 | * |
d89a3f73 | 520 | * %ESCAPE_SPACE: (special white space, not space itself) |
c8250381 AS |
521 | * '\f' - form feed |
522 | * '\n' - new line | |
523 | * '\r' - carriage return | |
524 | * '\t' - horizontal tab | |
525 | * '\v' - vertical tab | |
526 | * %ESCAPE_SPECIAL: | |
91027d0a | 527 | * '\"' - double quote |
c8250381 AS |
528 | * '\\' - backslash |
529 | * '\a' - alert (BEL) | |
530 | * '\e' - escape | |
531 | * %ESCAPE_NULL: | |
532 | * '\0' - null | |
533 | * %ESCAPE_OCTAL: | |
534 | * '\NNN' - byte with octal value NNN (3 digits) | |
535 | * %ESCAPE_ANY: | |
536 | * all previous together | |
537 | * %ESCAPE_NP: | |
a0809783 | 538 | * escape only non-printable characters, checked by isprint() |
c8250381 AS |
539 | * %ESCAPE_ANY_NP: |
540 | * all previous together | |
541 | * %ESCAPE_HEX: | |
542 | * '\xHH' - byte with hexadecimal value HH (2 digits) | |
a0809783 AS |
543 | * %ESCAPE_NA: |
544 | * escape only non-ascii characters, checked by isascii() | |
0362c27f AS |
545 | * %ESCAPE_NAP: |
546 | * escape only non-printable or non-ascii characters | |
aec0d096 AS |
547 | * %ESCAPE_APPEND: |
548 | * append characters from @only to be escaped by the given classes | |
549 | * | |
550 | * %ESCAPE_APPEND would help to pass additional characters to the escaped, when | |
551 | * one of %ESCAPE_NP, %ESCAPE_NA, or %ESCAPE_NAP is provided. | |
a0809783 | 552 | * |
0362c27f AS |
553 | * One notable caveat, the %ESCAPE_NAP, %ESCAPE_NP and %ESCAPE_NA have the |
554 | * higher priority than the rest of the flags (%ESCAPE_NAP is the highest). | |
a0809783 AS |
555 | * It doesn't make much sense to use either of them without %ESCAPE_OCTAL |
556 | * or %ESCAPE_HEX, because they cover most of the other character classes. | |
0362c27f AS |
557 | * %ESCAPE_NAP can utilize %ESCAPE_SPACE or %ESCAPE_SPECIAL in addition to |
558 | * the above. | |
c8250381 AS |
559 | * |
560 | * Return: | |
41416f23 RV |
561 | * The total size of the escaped output that would be generated for |
562 | * the given input and flags. To check whether the output was | |
563 | * truncated, compare the return value to osz. There is room left in | |
564 | * dst for a '\0' terminator if and only if ret < osz. | |
c8250381 | 565 | */ |
41416f23 | 566 | int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, |
b40bdb7f | 567 | unsigned int flags, const char *only) |
c8250381 | 568 | { |
41416f23 | 569 | char *p = dst; |
3aeddc7d | 570 | char *end = p + osz; |
b40bdb7f | 571 | bool is_dict = only && *only; |
aec0d096 | 572 | bool is_append = flags & ESCAPE_APPEND; |
c8250381 AS |
573 | |
574 | while (isz--) { | |
575 | unsigned char c = *src++; | |
aec0d096 | 576 | bool in_dict = is_dict && strchr(only, c); |
c8250381 AS |
577 | |
578 | /* | |
579 | * Apply rules in the following sequence: | |
b40bdb7f | 580 | * - the @only string is supplied and does not contain a |
c8250381 | 581 | * character under question |
0362c27f AS |
582 | * - the character is printable and ASCII, when @flags has |
583 | * %ESCAPE_NAP bit set | |
62519b88 AS |
584 | * - the character is printable, when @flags has |
585 | * %ESCAPE_NP bit set | |
a0809783 AS |
586 | * - the character is ASCII, when @flags has |
587 | * %ESCAPE_NA bit set | |
c8250381 AS |
588 | * - the character doesn't fall into a class of symbols |
589 | * defined by given @flags | |
590 | * In these cases we just pass through a character to the | |
591 | * output buffer. | |
aec0d096 AS |
592 | * |
593 | * When %ESCAPE_APPEND is passed, the characters from @only | |
594 | * have been excluded from the %ESCAPE_NAP, %ESCAPE_NP, and | |
595 | * %ESCAPE_NA cases. | |
c8250381 | 596 | */ |
aec0d096 | 597 | if (!(is_append || in_dict) && is_dict && |
7e5969ae AS |
598 | escape_passthrough(c, &p, end)) |
599 | continue; | |
62519b88 | 600 | |
aec0d096 | 601 | if (!(is_append && in_dict) && isascii(c) && isprint(c) && |
0362c27f AS |
602 | flags & ESCAPE_NAP && escape_passthrough(c, &p, end)) |
603 | continue; | |
604 | ||
aec0d096 | 605 | if (!(is_append && in_dict) && isprint(c) && |
7e5969ae AS |
606 | flags & ESCAPE_NP && escape_passthrough(c, &p, end)) |
607 | continue; | |
3aeddc7d | 608 | |
aec0d096 | 609 | if (!(is_append && in_dict) && isascii(c) && |
a0809783 AS |
610 | flags & ESCAPE_NA && escape_passthrough(c, &p, end)) |
611 | continue; | |
612 | ||
7e5969ae AS |
613 | if (flags & ESCAPE_SPACE && escape_space(c, &p, end)) |
614 | continue; | |
3aeddc7d | 615 | |
7e5969ae AS |
616 | if (flags & ESCAPE_SPECIAL && escape_special(c, &p, end)) |
617 | continue; | |
c8250381 | 618 | |
7e5969ae AS |
619 | if (flags & ESCAPE_NULL && escape_null(c, &p, end)) |
620 | continue; | |
3aeddc7d | 621 | |
7e5969ae AS |
622 | /* ESCAPE_OCTAL and ESCAPE_HEX always go last */ |
623 | if (flags & ESCAPE_OCTAL && escape_octal(c, &p, end)) | |
624 | continue; | |
625 | ||
626 | if (flags & ESCAPE_HEX && escape_hex(c, &p, end)) | |
627 | continue; | |
c8250381 | 628 | |
3aeddc7d | 629 | escape_passthrough(c, &p, end); |
c8250381 AS |
630 | } |
631 | ||
41416f23 | 632 | return p - dst; |
c8250381 AS |
633 | } |
634 | EXPORT_SYMBOL(string_escape_mem); | |
b53f27e4 KC |
635 | |
636 | /* | |
637 | * Return an allocated string that has been escaped of special characters | |
638 | * and double quotes, making it safe to log in quotes. | |
639 | */ | |
640 | char *kstrdup_quotable(const char *src, gfp_t gfp) | |
641 | { | |
642 | size_t slen, dlen; | |
643 | char *dst; | |
644 | const int flags = ESCAPE_HEX; | |
645 | const char esc[] = "\f\n\r\t\v\a\e\\\""; | |
646 | ||
647 | if (!src) | |
648 | return NULL; | |
649 | slen = strlen(src); | |
650 | ||
651 | dlen = string_escape_mem(src, slen, NULL, 0, flags, esc); | |
652 | dst = kmalloc(dlen + 1, gfp); | |
653 | if (!dst) | |
654 | return NULL; | |
655 | ||
656 | WARN_ON(string_escape_mem(src, slen, dst, dlen, flags, esc) != dlen); | |
657 | dst[dlen] = '\0'; | |
658 | ||
659 | return dst; | |
660 | } | |
661 | EXPORT_SYMBOL_GPL(kstrdup_quotable); | |
0d044328 KC |
662 | |
663 | /* | |
664 | * Returns allocated NULL-terminated string containing process | |
665 | * command line, with inter-argument NULLs replaced with spaces, | |
666 | * and other special characters escaped. | |
667 | */ | |
668 | char *kstrdup_quotable_cmdline(struct task_struct *task, gfp_t gfp) | |
669 | { | |
670 | char *buffer, *quoted; | |
671 | int i, res; | |
672 | ||
0ee931c4 | 673 | buffer = kmalloc(PAGE_SIZE, GFP_KERNEL); |
0d044328 KC |
674 | if (!buffer) |
675 | return NULL; | |
676 | ||
677 | res = get_cmdline(task, buffer, PAGE_SIZE - 1); | |
678 | buffer[res] = '\0'; | |
679 | ||
680 | /* Collapse trailing NULLs, leave res pointing to last non-NULL. */ | |
681 | while (--res >= 0 && buffer[res] == '\0') | |
682 | ; | |
683 | ||
684 | /* Replace inter-argument NULLs. */ | |
685 | for (i = 0; i <= res; i++) | |
686 | if (buffer[i] == '\0') | |
687 | buffer[i] = ' '; | |
688 | ||
689 | /* Make sure result is printable. */ | |
690 | quoted = kstrdup_quotable(buffer, gfp); | |
691 | kfree(buffer); | |
692 | return quoted; | |
693 | } | |
694 | EXPORT_SYMBOL_GPL(kstrdup_quotable_cmdline); | |
21985319 KC |
695 | |
696 | /* | |
697 | * Returns allocated NULL-terminated string containing pathname, | |
698 | * with special characters escaped, able to be safely logged. If | |
699 | * there is an error, the leading character will be "<". | |
700 | */ | |
701 | char *kstrdup_quotable_file(struct file *file, gfp_t gfp) | |
702 | { | |
703 | char *temp, *pathname; | |
704 | ||
705 | if (!file) | |
706 | return kstrdup("<unknown>", gfp); | |
707 | ||
708 | /* We add 11 spaces for ' (deleted)' to be appended */ | |
0ee931c4 | 709 | temp = kmalloc(PATH_MAX + 11, GFP_KERNEL); |
21985319 KC |
710 | if (!temp) |
711 | return kstrdup("<no_memory>", gfp); | |
712 | ||
713 | pathname = file_path(file, temp, PATH_MAX + 11); | |
714 | if (IS_ERR(pathname)) | |
715 | pathname = kstrdup("<too_long>", gfp); | |
716 | else | |
717 | pathname = kstrdup_quotable(pathname, gfp); | |
718 | ||
719 | kfree(temp); | |
720 | return pathname; | |
721 | } | |
722 | EXPORT_SYMBOL_GPL(kstrdup_quotable_file); | |
0fd16012 | 723 | |
045ad464 AS |
724 | /* |
725 | * Returns duplicate string in which the @old characters are replaced by @new. | |
726 | */ | |
727 | char *kstrdup_and_replace(const char *src, char old, char new, gfp_t gfp) | |
728 | { | |
729 | char *dst; | |
730 | ||
731 | dst = kstrdup(src, gfp); | |
732 | if (!dst) | |
733 | return NULL; | |
734 | ||
735 | return strreplace(dst, old, new); | |
736 | } | |
737 | EXPORT_SYMBOL_GPL(kstrdup_and_replace); | |
738 | ||
418e0a35 AS |
739 | /** |
740 | * kasprintf_strarray - allocate and fill array of sequential strings | |
741 | * @gfp: flags for the slab allocator | |
742 | * @prefix: prefix to be used | |
743 | * @n: amount of lines to be allocated and filled | |
744 | * | |
745 | * Allocates and fills @n strings using pattern "%s-%zu", where prefix | |
746 | * is provided by caller. The caller is responsible to free them with | |
747 | * kfree_strarray() after use. | |
748 | * | |
749 | * Returns array of strings or NULL when memory can't be allocated. | |
750 | */ | |
751 | char **kasprintf_strarray(gfp_t gfp, const char *prefix, size_t n) | |
752 | { | |
753 | char **names; | |
754 | size_t i; | |
755 | ||
756 | names = kcalloc(n + 1, sizeof(char *), gfp); | |
757 | if (!names) | |
758 | return NULL; | |
759 | ||
760 | for (i = 0; i < n; i++) { | |
761 | names[i] = kasprintf(gfp, "%s-%zu", prefix, i); | |
762 | if (!names[i]) { | |
763 | kfree_strarray(names, i); | |
764 | return NULL; | |
765 | } | |
766 | } | |
767 | ||
768 | return names; | |
769 | } | |
770 | EXPORT_SYMBOL_GPL(kasprintf_strarray); | |
771 | ||
0fd16012 BG |
772 | /** |
773 | * kfree_strarray - free a number of dynamically allocated strings contained | |
774 | * in an array and the array itself | |
775 | * | |
776 | * @array: Dynamically allocated array of strings to free. | |
777 | * @n: Number of strings (starting from the beginning of the array) to free. | |
778 | * | |
779 | * Passing a non-NULL @array and @n == 0 as well as NULL @array are valid | |
780 | * use-cases. If @array is NULL, the function does nothing. | |
781 | */ | |
782 | void kfree_strarray(char **array, size_t n) | |
783 | { | |
784 | unsigned int i; | |
785 | ||
786 | if (!array) | |
787 | return; | |
788 | ||
789 | for (i = 0; i < n; i++) | |
790 | kfree(array[i]); | |
791 | kfree(array); | |
792 | } | |
793 | EXPORT_SYMBOL_GPL(kfree_strarray); | |
cfecea6e | 794 | |
acdb89b6 AS |
795 | struct strarray { |
796 | char **array; | |
797 | size_t n; | |
798 | }; | |
799 | ||
800 | static void devm_kfree_strarray(struct device *dev, void *res) | |
801 | { | |
802 | struct strarray *array = res; | |
803 | ||
804 | kfree_strarray(array->array, array->n); | |
805 | } | |
806 | ||
807 | char **devm_kasprintf_strarray(struct device *dev, const char *prefix, size_t n) | |
808 | { | |
809 | struct strarray *ptr; | |
810 | ||
811 | ptr = devres_alloc(devm_kfree_strarray, sizeof(*ptr), GFP_KERNEL); | |
812 | if (!ptr) | |
813 | return ERR_PTR(-ENOMEM); | |
814 | ||
815 | ptr->array = kasprintf_strarray(GFP_KERNEL, prefix, n); | |
816 | if (!ptr->array) { | |
817 | devres_free(ptr); | |
818 | return ERR_PTR(-ENOMEM); | |
819 | } | |
820 | ||
cd290a98 PL |
821 | ptr->n = n; |
822 | devres_add(dev, ptr); | |
823 | ||
acdb89b6 AS |
824 | return ptr->array; |
825 | } | |
826 | EXPORT_SYMBOL_GPL(devm_kasprintf_strarray); | |
827 | ||
cfecea6e KC |
828 | /** |
829 | * strscpy_pad() - Copy a C-string into a sized buffer | |
830 | * @dest: Where to copy the string to | |
831 | * @src: Where to copy the string from | |
832 | * @count: Size of destination buffer | |
833 | * | |
834 | * Copy the string, or as much of it as fits, into the dest buffer. The | |
835 | * behavior is undefined if the string buffers overlap. The destination | |
836 | * buffer is always %NUL terminated, unless it's zero-sized. | |
837 | * | |
838 | * If the source string is shorter than the destination buffer, zeros | |
839 | * the tail of the destination buffer. | |
840 | * | |
841 | * For full explanation of why you may want to consider using the | |
842 | * 'strscpy' functions please see the function docstring for strscpy(). | |
843 | * | |
844 | * Returns: | |
845 | * * The number of characters copied (not including the trailing %NUL) | |
846 | * * -E2BIG if count is 0 or @src was truncated. | |
847 | */ | |
848 | ssize_t strscpy_pad(char *dest, const char *src, size_t count) | |
849 | { | |
850 | ssize_t written; | |
851 | ||
852 | written = strscpy(dest, src, count); | |
853 | if (written < 0 || written == count - 1) | |
854 | return written; | |
855 | ||
856 | memset(dest + written + 1, 0, count - written - 1); | |
857 | ||
858 | return written; | |
859 | } | |
860 | EXPORT_SYMBOL(strscpy_pad); | |
861 | ||
862 | /** | |
863 | * skip_spaces - Removes leading whitespace from @str. | |
864 | * @str: The string to be stripped. | |
865 | * | |
866 | * Returns a pointer to the first non-whitespace character in @str. | |
867 | */ | |
868 | char *skip_spaces(const char *str) | |
869 | { | |
870 | while (isspace(*str)) | |
871 | ++str; | |
872 | return (char *)str; | |
873 | } | |
874 | EXPORT_SYMBOL(skip_spaces); | |
875 | ||
876 | /** | |
877 | * strim - Removes leading and trailing whitespace from @s. | |
878 | * @s: The string to be stripped. | |
879 | * | |
880 | * Note that the first trailing whitespace is replaced with a %NUL-terminator | |
881 | * in the given string @s. Returns a pointer to the first non-whitespace | |
882 | * character in @s. | |
883 | */ | |
884 | char *strim(char *s) | |
885 | { | |
886 | size_t size; | |
887 | char *end; | |
888 | ||
889 | size = strlen(s); | |
890 | if (!size) | |
891 | return s; | |
892 | ||
893 | end = s + size - 1; | |
894 | while (end >= s && isspace(*end)) | |
895 | end--; | |
896 | *(end + 1) = '\0'; | |
897 | ||
898 | return skip_spaces(s); | |
899 | } | |
900 | EXPORT_SYMBOL(strim); | |
901 | ||
902 | /** | |
903 | * sysfs_streq - return true if strings are equal, modulo trailing newline | |
904 | * @s1: one string | |
905 | * @s2: another string | |
906 | * | |
907 | * This routine returns true iff two strings are equal, treating both | |
908 | * NUL and newline-then-NUL as equivalent string terminations. It's | |
909 | * geared for use with sysfs input strings, which generally terminate | |
910 | * with newlines but are compared against values without newlines. | |
911 | */ | |
912 | bool sysfs_streq(const char *s1, const char *s2) | |
913 | { | |
914 | while (*s1 && *s1 == *s2) { | |
915 | s1++; | |
916 | s2++; | |
917 | } | |
918 | ||
919 | if (*s1 == *s2) | |
920 | return true; | |
921 | if (!*s1 && *s2 == '\n' && !s2[1]) | |
922 | return true; | |
923 | if (*s1 == '\n' && !s1[1] && !*s2) | |
924 | return true; | |
925 | return false; | |
926 | } | |
927 | EXPORT_SYMBOL(sysfs_streq); | |
928 | ||
929 | /** | |
930 | * match_string - matches given string in an array | |
931 | * @array: array of strings | |
932 | * @n: number of strings in the array or -1 for NULL terminated arrays | |
933 | * @string: string to match with | |
934 | * | |
935 | * This routine will look for a string in an array of strings up to the | |
936 | * n-th element in the array or until the first NULL element. | |
937 | * | |
938 | * Historically the value of -1 for @n, was used to search in arrays that | |
939 | * are NULL terminated. However, the function does not make a distinction | |
940 | * when finishing the search: either @n elements have been compared OR | |
941 | * the first NULL element was found. | |
942 | * | |
943 | * Return: | |
944 | * index of a @string in the @array if matches, or %-EINVAL otherwise. | |
945 | */ | |
946 | int match_string(const char * const *array, size_t n, const char *string) | |
947 | { | |
948 | int index; | |
949 | const char *item; | |
950 | ||
951 | for (index = 0; index < n; index++) { | |
952 | item = array[index]; | |
953 | if (!item) | |
954 | break; | |
955 | if (!strcmp(item, string)) | |
956 | return index; | |
957 | } | |
958 | ||
959 | return -EINVAL; | |
960 | } | |
961 | EXPORT_SYMBOL(match_string); | |
962 | ||
963 | /** | |
964 | * __sysfs_match_string - matches given string in an array | |
965 | * @array: array of strings | |
966 | * @n: number of strings in the array or -1 for NULL terminated arrays | |
967 | * @str: string to match with | |
968 | * | |
969 | * Returns index of @str in the @array or -EINVAL, just like match_string(). | |
970 | * Uses sysfs_streq instead of strcmp for matching. | |
971 | * | |
972 | * This routine will look for a string in an array of strings up to the | |
973 | * n-th element in the array or until the first NULL element. | |
974 | * | |
975 | * Historically the value of -1 for @n, was used to search in arrays that | |
976 | * are NULL terminated. However, the function does not make a distinction | |
977 | * when finishing the search: either @n elements have been compared OR | |
978 | * the first NULL element was found. | |
979 | */ | |
980 | int __sysfs_match_string(const char * const *array, size_t n, const char *str) | |
981 | { | |
982 | const char *item; | |
983 | int index; | |
984 | ||
985 | for (index = 0; index < n; index++) { | |
986 | item = array[index]; | |
987 | if (!item) | |
988 | break; | |
989 | if (sysfs_streq(item, str)) | |
990 | return index; | |
991 | } | |
992 | ||
993 | return -EINVAL; | |
994 | } | |
995 | EXPORT_SYMBOL(__sysfs_match_string); | |
996 | ||
997 | /** | |
998 | * strreplace - Replace all occurrences of character in string. | |
d01a77af | 999 | * @str: The string to operate on. |
cfecea6e KC |
1000 | * @old: The character being replaced. |
1001 | * @new: The character @old is replaced with. | |
1002 | * | |
d01a77af AS |
1003 | * Replaces the each @old character with a @new one in the given string @str. |
1004 | * | |
1005 | * Return: pointer to the string @str itself. | |
cfecea6e | 1006 | */ |
d01a77af | 1007 | char *strreplace(char *str, char old, char new) |
cfecea6e | 1008 | { |
d01a77af AS |
1009 | char *s = str; |
1010 | ||
cfecea6e KC |
1011 | for (; *s; ++s) |
1012 | if (*s == old) | |
1013 | *s = new; | |
d01a77af | 1014 | return str; |
cfecea6e KC |
1015 | } |
1016 | EXPORT_SYMBOL(strreplace); | |
1017 | ||
5c4e0a21 GR |
1018 | /** |
1019 | * memcpy_and_pad - Copy one buffer to another with padding | |
1020 | * @dest: Where to copy to | |
1021 | * @dest_len: The destination buffer size | |
1022 | * @src: Where to copy from | |
1023 | * @count: The number of bytes to copy | |
1024 | * @pad: Character to use for padding if space is left in destination. | |
1025 | */ | |
1026 | void memcpy_and_pad(void *dest, size_t dest_len, const void *src, size_t count, | |
1027 | int pad) | |
1028 | { | |
1029 | if (dest_len > count) { | |
1030 | memcpy(dest, src, count); | |
1031 | memset(dest + count, pad, dest_len - count); | |
1032 | } else { | |
1033 | memcpy(dest, src, dest_len); | |
1034 | } | |
1035 | } | |
1036 | EXPORT_SYMBOL(memcpy_and_pad); | |
1037 | ||
c430f600 | 1038 | #ifdef CONFIG_FORTIFY_SOURCE |
f68f2ff9 KC |
1039 | /* These are placeholders for fortify compile-time warnings. */ |
1040 | void __read_overflow2_field(size_t avail, size_t wanted) { } | |
1041 | EXPORT_SYMBOL(__read_overflow2_field); | |
1042 | void __write_overflow_field(size_t avail, size_t wanted) { } | |
1043 | EXPORT_SYMBOL(__write_overflow_field); | |
1044 | ||
cfecea6e KC |
1045 | void fortify_panic(const char *name) |
1046 | { | |
1047 | pr_emerg("detected buffer overflow in %s\n", name); | |
1048 | BUG(); | |
1049 | } | |
1050 | EXPORT_SYMBOL(fortify_panic); | |
c430f600 | 1051 | #endif /* CONFIG_FORTIFY_SOURCE */ |