diff options
Diffstat (limited to 'lib/parser.c')
| -rw-r--r-- | lib/parser.c | 211 |
1 files changed, 168 insertions, 43 deletions
diff --git a/lib/parser.c b/lib/parser.c index 807b2aaa33fa..73e8f8e5be73 100644 --- a/lib/parser.c +++ b/lib/parser.c @@ -1,19 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * lib/parser.c - simple parser for mount, etc. options. - * - * This source code is licensed under the GNU General Public License, - * Version 2. See the file COPYING for more details. */ #include <linux/ctype.h> #include <linux/types.h> #include <linux/export.h> +#include <linux/kstrtox.h> #include <linux/parser.h> #include <linux/slab.h> #include <linux/string.h> +/* + * max size needed by different bases to express U64 + * HEX: "0xFFFFFFFFFFFFFFFF" --> 18 + * DEC: "18446744073709551615" --> 20 + * OCT: "01777777777777777777777" --> 23 + * pick the max one to define NUMBER_BUF_LEN + */ +#define NUMBER_BUF_LEN 24 + /** - * match_one: - Determines if a string matches a simple pattern + * match_one - Determines if a string matches a simple pattern * @s: the string to examine for presence of the pattern * @p: the string containing the pattern * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match @@ -91,7 +99,7 @@ static int match_one(char *s, const char *p, substring_t args[]) } /** - * match_token: - Find a token (and optional args) in a string + * match_token - Find a token (and optional args) in a string * @s: the string to examine for token/argument pairs * @table: match_table_t describing the set of allowed option tokens and the * arguments that may be associated with them. Must be terminated with a @@ -100,7 +108,7 @@ static int match_one(char *s, const char *p, substring_t args[]) * locations. * * Description: Detects which if any of a set of token strings has been passed - * to it. Tokens can include up to MAX_OPT_ARGS instances of basic c-style + * to it. Tokens can include up to %MAX_OPT_ARGS instances of basic c-style * format identifiers which will be taken into account when matching the * tokens, and whose locations will be returned in the @args array. */ @@ -113,31 +121,29 @@ int match_token(char *s, const match_table_t table, substring_t args[]) return p->token; } +EXPORT_SYMBOL(match_token); /** - * match_number: scan a number in the given base from a substring_t + * match_number - scan a number in the given base from a substring_t * @s: substring to be scanned * @result: resulting integer on success * @base: base to use when converting string * * Description: Given a &substring_t and a base, attempts to parse the substring - * as a number in that base. On success, sets @result to the integer represented - * by the string and returns 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure. + * as a number in that base. + * + * Return: On success, sets @result to the integer represented by the + * string and returns 0. Returns -EINVAL or -ERANGE on failure. */ static int match_number(substring_t *s, int *result, int base) { char *endp; - char *buf; + char buf[NUMBER_BUF_LEN]; int ret; long val; - size_t len = s->to - s->from; - - buf = kmalloc(len + 1, GFP_KERNEL); - if (!buf) - return -ENOMEM; - memcpy(buf, s->from, len); - buf[len] = '\0'; + if (match_strlcpy(buf, s, NUMBER_BUF_LEN) >= NUMBER_BUF_LEN) + return -ERANGE; ret = 0; val = simple_strtol(buf, &endp, base); if (endp == buf) @@ -146,61 +152,186 @@ static int match_number(substring_t *s, int *result, int base) ret = -ERANGE; else *result = (int) val; - kfree(buf); return ret; } /** - * match_int: - scan a decimal representation of an integer from a substring_t + * match_u64int - scan a number in the given base from a substring_t + * @s: substring to be scanned + * @result: resulting u64 on success + * @base: base to use when converting string + * + * Description: Given a &substring_t and a base, attempts to parse the substring + * as a number in that base. + * + * Return: On success, sets @result to the integer represented by the + * string and returns 0. Returns -EINVAL or -ERANGE on failure. + */ +static int match_u64int(substring_t *s, u64 *result, int base) +{ + char buf[NUMBER_BUF_LEN]; + int ret; + u64 val; + + if (match_strlcpy(buf, s, NUMBER_BUF_LEN) >= NUMBER_BUF_LEN) + return -ERANGE; + ret = kstrtoull(buf, base, &val); + if (!ret) + *result = val; + return ret; +} + +/** + * match_int - scan a decimal representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * - * Description: Attempts to parse the &substring_t @s as a decimal integer. On - * success, sets @result to the integer represented by the string and returns 0. - * Returns -ENOMEM, -EINVAL, or -ERANGE on failure. + * Description: Attempts to parse the &substring_t @s as a decimal integer. + * + * Return: On success, sets @result to the integer represented by the string + * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_int(substring_t *s, int *result) { return match_number(s, result, 0); } +EXPORT_SYMBOL(match_int); /** - * match_octal: - scan an octal representation of an integer from a substring_t + * match_uint - scan a decimal representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * - * Description: Attempts to parse the &substring_t @s as an octal integer. On - * success, sets @result to the integer represented by the string and returns - * 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure. + * Description: Attempts to parse the &substring_t @s as a decimal integer. + * + * Return: On success, sets @result to the integer represented by the string + * and returns 0. Returns -EINVAL or -ERANGE on failure. + */ +int match_uint(substring_t *s, unsigned int *result) +{ + char buf[NUMBER_BUF_LEN]; + + if (match_strlcpy(buf, s, NUMBER_BUF_LEN) >= NUMBER_BUF_LEN) + return -ERANGE; + + return kstrtouint(buf, 10, result); +} +EXPORT_SYMBOL(match_uint); + +/** + * match_u64 - scan a decimal representation of a u64 from + * a substring_t + * @s: substring_t to be scanned + * @result: resulting unsigned long long on success + * + * Description: Attempts to parse the &substring_t @s as a long decimal + * integer. + * + * Return: On success, sets @result to the integer represented by the string + * and returns 0. Returns -EINVAL or -ERANGE on failure. + */ +int match_u64(substring_t *s, u64 *result) +{ + return match_u64int(s, result, 0); +} +EXPORT_SYMBOL(match_u64); + +/** + * match_octal - scan an octal representation of an integer from a substring_t + * @s: substring_t to be scanned + * @result: resulting integer on success + * + * Description: Attempts to parse the &substring_t @s as an octal integer. + * + * Return: On success, sets @result to the integer represented by the string + * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_octal(substring_t *s, int *result) { return match_number(s, result, 8); } +EXPORT_SYMBOL(match_octal); /** - * match_hex: - scan a hex representation of an integer from a substring_t + * match_hex - scan a hex representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * * Description: Attempts to parse the &substring_t @s as a hexadecimal integer. - * On success, sets @result to the integer represented by the string and - * returns 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure. + * + * Return: On success, sets @result to the integer represented by the string + * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_hex(substring_t *s, int *result) { return match_number(s, result, 16); } +EXPORT_SYMBOL(match_hex); /** - * match_strlcpy: - Copy the characters from a substring_t to a sized buffer + * match_wildcard - parse if a string matches given wildcard pattern + * @pattern: wildcard pattern + * @str: the string to be parsed + * + * Description: Parse the string @str to check if matches wildcard + * pattern @pattern. The pattern may contain two types of wildcards: + * + * * '*' - matches zero or more characters + * * '?' - matches one character + * + * Return: If the @str matches the @pattern, return true, else return false. + */ +bool match_wildcard(const char *pattern, const char *str) +{ + const char *s = str; + const char *p = pattern; + bool star = false; + + while (*s) { + switch (*p) { + case '?': + s++; + p++; + break; + case '*': + star = true; + str = s; + if (!*++p) + return true; + pattern = p; + break; + default: + if (*s == *p) { + s++; + p++; + } else { + if (!star) + return false; + str++; + s = str; + p = pattern; + } + break; + } + } + + if (*p == '*') + ++p; + return !*p; +} +EXPORT_SYMBOL(match_wildcard); + +/** + * match_strlcpy - Copy the characters from a substring_t to a sized buffer * @dest: where to copy to * @src: &substring_t to copy * @size: size of destination buffer * * Description: Copy the characters in &substring_t @src to the * c-style string @dest. Copy no more than @size - 1 characters, plus - * the terminating NUL. Return length of @src. + * the terminating NUL. + * + * Return: length of @src. */ size_t match_strlcpy(char *dest, const substring_t *src, size_t size) { @@ -213,27 +344,21 @@ size_t match_strlcpy(char *dest, const substring_t *src, size_t size) } return ret; } +EXPORT_SYMBOL(match_strlcpy); /** - * match_strdup: - allocate a new string with the contents of a substring_t + * match_strdup - allocate a new string with the contents of a substring_t * @s: &substring_t to copy * * Description: Allocates and returns a string filled with the contents of * the &substring_t @s. The caller is responsible for freeing the returned * string with kfree(). + * + * Return: the address of the newly allocated NUL-terminated string or + * %NULL on error. */ char *match_strdup(const substring_t *s) { - size_t sz = s->to - s->from + 1; - char *p = kmalloc(sz, GFP_KERNEL); - if (p) - match_strlcpy(p, s, sz); - return p; + return kmemdup_nul(s->from, s->to - s->from, GFP_KERNEL); } - -EXPORT_SYMBOL(match_token); -EXPORT_SYMBOL(match_int); -EXPORT_SYMBOL(match_octal); -EXPORT_SYMBOL(match_hex); -EXPORT_SYMBOL(match_strlcpy); EXPORT_SYMBOL(match_strdup); |