| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Convert integer string representation to an integer. |
| * If an integer doesn't fit into specified type, -E is returned. |
| * |
| * Integer starts with optional sign. |
| * kstrtou*() functions do not accept sign "-". |
| * |
| * Radix 0 means autodetection: leading "0x" implies radix 16, |
| * leading "0" implies radix 8, otherwise radix is 10. |
| * Autodetection hints work after optional sign, but not before. |
| * |
| * If -E is returned, result is not touched. |
| */ |
| #include <linux/ctype.h> |
| #include <linux/errno.h> |
| #include <linux/kernel.h> |
| #include <linux/math64.h> |
| #include <linux/export.h> |
| #include <linux/types.h> |
| #include <linux/uaccess.h> |
| #include "kstrtox.h" |
| |
| const char *_parse_integer_fixup_radix(const char *s, unsigned int *base) |
| { |
| if (*base == 0) { |
| if (s[0] == '0') { |
| if (_tolower(s[1]) == 'x' && isxdigit(s[2])) |
| *base = 16; |
| else |
| *base = 8; |
| } else |
| *base = 10; |
| } |
| if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x') |
| s += 2; |
| return s; |
| } |
| |
| /* |
| * Convert non-negative integer string representation in explicitly given radix |
| * to an integer. A maximum of max_chars characters will be converted. |
| * |
| * Return number of characters consumed maybe or-ed with overflow bit. |
| * If overflow occurs, result integer (incorrect) is still returned. |
| * |
| * Don't you dare use this function. |
| */ |
| unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned long long *p, |
| size_t max_chars) |
| { |
| unsigned long long res; |
| unsigned int rv; |
| |
| res = 0; |
| rv = 0; |
| while (max_chars--) { |
| unsigned int c = *s; |
| unsigned int lc = c | 0x20; /* don't tolower() this line */ |
| unsigned int val; |
| |
| if ('0' <= c && c <= '9') |
| val = c - '0'; |
| else if ('a' <= lc && lc <= 'f') |
| val = lc - 'a' + 10; |
| else |
| break; |
| |
| if (val >= base) |
| break; |
| /* |
| * Check for overflow only if we are within range of |
| * it in the max base we support (16) |
| */ |
| if (unlikely(res & (~0ull << 60))) { |
| if (res > div_u64(ULLONG_MAX - val, base)) |
| rv |= KSTRTOX_OVERFLOW; |
| } |
| res = res * base + val; |
| rv++; |
| s++; |
| } |
| *p = res; |
| return rv; |
| } |
| |
| unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p) |
| { |
| return _parse_integer_limit(s, base, p, INT_MAX); |
| } |
| |
| static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res) |
| { |
| unsigned long long _res; |
| unsigned int rv; |
| |
| s = _parse_integer_fixup_radix(s, &base); |
| rv = _parse_integer(s, base, &_res); |
| if (rv & KSTRTOX_OVERFLOW) |
| return -ERANGE; |
| if (rv == 0) |
| return -EINVAL; |
| s += rv; |
| if (*s == '\n') |
| s++; |
| if (*s) |
| return -EINVAL; |
| *res = _res; |
| return 0; |
| } |
| |
| /** |
| * kstrtoull - convert a string to an unsigned long long |
| * @s: The start of the string. The string must be null-terminated, and may also |
| * include a single newline before its terminating null. The first character |
| * may also be a plus sign, but not a minus sign. |
| * @base: The number base to use. The maximum supported base is 16. If base is |
| * given as 0, then the base of the string is automatically detected with the |
| * conventional semantics - If it begins with 0x the number will be parsed as a |
| * hexadecimal (case insensitive), if it otherwise begins with 0, it will be |
| * parsed as an octal number. Otherwise it will be parsed as a decimal. |
| * @res: Where to write the result of the conversion on success. |
| * |
| * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. |
| * Used as a replacement for the obsolete simple_strtoull. Return code must |
| * be checked. |
| */ |
| int kstrtoull(const char *s, unsigned int base, unsigned long long *res) |
| { |
| if (s[0] == '+') |
| s++; |
| return _kstrtoull(s, base, res); |
| } |
| EXPORT_SYMBOL(kstrtoull); |
| |
| /** |
| * kstrtoll - convert a string to a long long |
| * @s: The start of the string. The string must be null-terminated, and may also |
| * include a single newline before its terminating null. The first character |
| * may also be a plus sign or a minus sign. |
| * @base: The number base to use. The maximum supported base is 16. If base is |
| * given as 0, then the base of the string is automatically detected with the |
| * conventional semantics - If it begins with 0x the number will be parsed as a |
| * hexadecimal (case insensitive), if it otherwise begins with 0, it will be |
| * parsed as an octal number. Otherwise it will be parsed as a decimal. |
| * @res: Where to write the result of the conversion on success. |
| * |
| * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. |
| * Used as a replacement for the obsolete simple_strtoull. Return code must |
| * be checked. |
| */ |
| int kstrtoll(const char *s, unsigned int base, long long *res) |
| { |
| unsigned long long tmp; |
| int rv; |
| |
| if (s[0] == '-') { |
| rv = _kstrtoull(s + 1, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if ((long long)-tmp > 0) |
| return -ERANGE; |
| *res = -tmp; |
| } else { |
| rv = kstrtoull(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if ((long long)tmp < 0) |
| return -ERANGE; |
| *res = tmp; |
| } |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtoll); |
| |
| /* Internal, do not use. */ |
| int _kstrtoul(const char *s, unsigned int base, unsigned long *res) |
| { |
| unsigned long long tmp; |
| int rv; |
| |
| rv = kstrtoull(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (unsigned long)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(_kstrtoul); |
| |
| /* Internal, do not use. */ |
| int _kstrtol(const char *s, unsigned int base, long *res) |
| { |
| long long tmp; |
| int rv; |
| |
| rv = kstrtoll(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (long)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(_kstrtol); |
| |
| /** |
| * kstrtouint - convert a string to an unsigned int |
| * @s: The start of the string. The string must be null-terminated, and may also |
| * include a single newline before its terminating null. The first character |
| * may also be a plus sign, but not a minus sign. |
| * @base: The number base to use. The maximum supported base is 16. If base is |
| * given as 0, then the base of the string is automatically detected with the |
| * conventional semantics - If it begins with 0x the number will be parsed as a |
| * hexadecimal (case insensitive), if it otherwise begins with 0, it will be |
| * parsed as an octal number. Otherwise it will be parsed as a decimal. |
| * @res: Where to write the result of the conversion on success. |
| * |
| * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. |
| * Used as a replacement for the obsolete simple_strtoull. Return code must |
| * be checked. |
| */ |
| int kstrtouint(const char *s, unsigned int base, unsigned int *res) |
| { |
| unsigned long long tmp; |
| int rv; |
| |
| rv = kstrtoull(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (unsigned int)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtouint); |
| |
| /** |
| * kstrtoint - convert a string to an int |
| * @s: The start of the string. The string must be null-terminated, and may also |
| * include a single newline before its terminating null. The first character |
| * may also be a plus sign or a minus sign. |
| * @base: The number base to use. The maximum supported base is 16. If base is |
| * given as 0, then the base of the string is automatically detected with the |
| * conventional semantics - If it begins with 0x the number will be parsed as a |
| * hexadecimal (case insensitive), if it otherwise begins with 0, it will be |
| * parsed as an octal number. Otherwise it will be parsed as a decimal. |
| * @res: Where to write the result of the conversion on success. |
| * |
| * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. |
| * Used as a replacement for the obsolete simple_strtoull. Return code must |
| * be checked. |
| */ |
| int kstrtoint(const char *s, unsigned int base, int *res) |
| { |
| long long tmp; |
| int rv; |
| |
| rv = kstrtoll(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (int)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtoint); |
| |
| int kstrtou16(const char *s, unsigned int base, u16 *res) |
| { |
| unsigned long long tmp; |
| int rv; |
| |
| rv = kstrtoull(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (u16)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtou16); |
| |
| int kstrtos16(const char *s, unsigned int base, s16 *res) |
| { |
| long long tmp; |
| int rv; |
| |
| rv = kstrtoll(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (s16)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtos16); |
| |
| int kstrtou8(const char *s, unsigned int base, u8 *res) |
| { |
| unsigned long long tmp; |
| int rv; |
| |
| rv = kstrtoull(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (u8)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtou8); |
| |
| int kstrtos8(const char *s, unsigned int base, s8 *res) |
| { |
| long long tmp; |
| int rv; |
| |
| rv = kstrtoll(s, base, &tmp); |
| if (rv < 0) |
| return rv; |
| if (tmp != (s8)tmp) |
| return -ERANGE; |
| *res = tmp; |
| return 0; |
| } |
| EXPORT_SYMBOL(kstrtos8); |
| |
| /** |
| * kstrtobool - convert common user inputs into boolean values |
| * @s: input string |
| * @res: result |
| * |
| * This routine returns 0 iff the first character is one of 'Yy1Nn0', or |
| * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL. Value |
| * pointed to by res is updated upon finding a match. |
| */ |
| int kstrtobool(const char *s, bool *res) |
| { |
| if (!s) |
| return -EINVAL; |
| |
| switch (s[0]) { |
| case 'y': |
| case 'Y': |
| case '1': |
| *res = true; |
| return 0; |
| case 'n': |
| case 'N': |
| case '0': |
| *res = false; |
| return 0; |
| case 'o': |
| case 'O': |
| switch (s[1]) { |
| case 'n': |
| case 'N': |
| *res = true; |
| return 0; |
| case 'f': |
| case 'F': |
| *res = false; |
| return 0; |
| default: |
| break; |
| } |
| default: |
| break; |
| } |
| |
| return -EINVAL; |
| } |
| EXPORT_SYMBOL(kstrtobool); |
| |
| /* |
| * Since "base" would be a nonsense argument, this open-codes the |
| * _from_user helper instead of using the helper macro below. |
| */ |
| int kstrtobool_from_user(const char __user *s, size_t count, bool *res) |
| { |
| /* Longest string needed to differentiate, newline, terminator */ |
| char buf[4]; |
| |
| count = min(count, sizeof(buf) - 1); |
| if (copy_from_user(buf, s, count)) |
| return -EFAULT; |
| buf[count] = '\0'; |
| return kstrtobool(buf, res); |
| } |
| EXPORT_SYMBOL(kstrtobool_from_user); |
| |
| #define kstrto_from_user(f, g, type) \ |
| int f(const char __user *s, size_t count, unsigned int base, type *res) \ |
| { \ |
| /* sign, base 2 representation, newline, terminator */ \ |
| char buf[1 + sizeof(type) * 8 + 1 + 1]; \ |
| \ |
| count = min(count, sizeof(buf) - 1); \ |
| if (copy_from_user(buf, s, count)) \ |
| return -EFAULT; \ |
| buf[count] = '\0'; \ |
| return g(buf, base, res); \ |
| } \ |
| EXPORT_SYMBOL(f) |
| |
| kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long); |
| kstrto_from_user(kstrtoll_from_user, kstrtoll, long long); |
| kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long); |
| kstrto_from_user(kstrtol_from_user, kstrtol, long); |
| kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int); |
| kstrto_from_user(kstrtoint_from_user, kstrtoint, int); |
| kstrto_from_user(kstrtou16_from_user, kstrtou16, u16); |
| kstrto_from_user(kstrtos16_from_user, kstrtos16, s16); |
| kstrto_from_user(kstrtou8_from_user, kstrtou8, u8); |
| kstrto_from_user(kstrtos8_from_user, kstrtos8, s8); |