linux/fs/ksmbd/unicode.h
Atte Heikkilä 16b5f54e30 ksmbd: casefold utf-8 share names and fix ascii lowercase conversion
strtolower() corrupts all UTF-8 share names that have a byte in the C0
(À ISO8859-1) to DE (Þ ISO8859-1) range, since the non-ASCII part of
ISO8859-1 is incompatible with UTF-8. Prevent this by checking that a
byte is in the ASCII range with isascii(), before the conversion to
lowercase with tolower(). Properly handle case-insensitivity of UTF-8
share names by casefolding them, but fallback to ASCII lowercase
conversion on failure or if CONFIG_UNICODE is not set. Refactor to move
the share name casefolding immediately after the share name extraction.
Also, make the associated constness corrections.

Signed-off-by: Atte Heikkilä <atteh.mailbox@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-10-05 01:15:37 -05:00

359 lines
8.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Some of the source code in this file came from fs/cifs/cifs_unicode.c
* cifs_unicode: Unicode kernel case support
*
* Function:
* Convert a unicode character to upper or lower case using
* compressed tables.
*
* Copyright (c) International Business Machines Corp., 2000,2009
*
*
* Notes:
* These APIs are based on the C library functions. The semantics
* should match the C functions but with expanded size operands.
*
* The upper/lower functions are based on a table created by mkupr.
* This is a compressed table of upper and lower case conversion.
*
*/
#ifndef _CIFS_UNICODE_H
#define _CIFS_UNICODE_H
#include <asm/byteorder.h>
#include <linux/types.h>
#include <linux/nls.h>
#include <linux/unicode.h>
#define UNIUPR_NOLOWER /* Example to not expand lower case tables */
/*
* Windows maps these to the user defined 16 bit Unicode range since they are
* reserved symbols (along with \ and /), otherwise illegal to store
* in filenames in NTFS
*/
#define UNI_ASTERISK ((__u16)('*' + 0xF000))
#define UNI_QUESTION ((__u16)('?' + 0xF000))
#define UNI_COLON ((__u16)(':' + 0xF000))
#define UNI_GRTRTHAN ((__u16)('>' + 0xF000))
#define UNI_LESSTHAN ((__u16)('<' + 0xF000))
#define UNI_PIPE ((__u16)('|' + 0xF000))
#define UNI_SLASH ((__u16)('\\' + 0xF000))
/* Just define what we want from uniupr.h. We don't want to define the tables
* in each source file.
*/
#ifndef UNICASERANGE_DEFINED
struct UniCaseRange {
wchar_t start;
wchar_t end;
signed char *table;
};
#endif /* UNICASERANGE_DEFINED */
#ifndef UNIUPR_NOUPPER
extern signed char SmbUniUpperTable[512];
extern const struct UniCaseRange SmbUniUpperRange[];
#endif /* UNIUPR_NOUPPER */
#ifndef UNIUPR_NOLOWER
extern signed char CifsUniLowerTable[512];
extern const struct UniCaseRange CifsUniLowerRange[];
#endif /* UNIUPR_NOLOWER */
#ifdef __KERNEL__
int smb_strtoUTF16(__le16 *to, const char *from, int len,
const struct nls_table *codepage);
char *smb_strndup_from_utf16(const char *src, const int maxlen,
const bool is_unicode,
const struct nls_table *codepage);
int smbConvertToUTF16(__le16 *target, const char *source, int srclen,
const struct nls_table *cp, int mapchars);
char *ksmbd_extract_sharename(struct unicode_map *um, const char *treename);
#endif
/*
* UniStrcat: Concatenate the second string to the first
*
* Returns:
* Address of the first string
*/
static inline wchar_t *UniStrcat(wchar_t *ucs1, const wchar_t *ucs2)
{
wchar_t *anchor = ucs1; /* save a pointer to start of ucs1 */
while (*ucs1++)
/*NULL*/; /* To end of first string */
ucs1--; /* Return to the null */
while ((*ucs1++ = *ucs2++))
/*NULL*/; /* copy string 2 over */
return anchor;
}
/*
* UniStrchr: Find a character in a string
*
* Returns:
* Address of first occurrence of character in string
* or NULL if the character is not in the string
*/
static inline wchar_t *UniStrchr(const wchar_t *ucs, wchar_t uc)
{
while ((*ucs != uc) && *ucs)
ucs++;
if (*ucs == uc)
return (wchar_t *)ucs;
return NULL;
}
/*
* UniStrcmp: Compare two strings
*
* Returns:
* < 0: First string is less than second
* = 0: Strings are equal
* > 0: First string is greater than second
*/
static inline int UniStrcmp(const wchar_t *ucs1, const wchar_t *ucs2)
{
while ((*ucs1 == *ucs2) && *ucs1) {
ucs1++;
ucs2++;
}
return (int)*ucs1 - (int)*ucs2;
}
/*
* UniStrcpy: Copy a string
*/
static inline wchar_t *UniStrcpy(wchar_t *ucs1, const wchar_t *ucs2)
{
wchar_t *anchor = ucs1; /* save the start of result string */
while ((*ucs1++ = *ucs2++))
/*NULL*/;
return anchor;
}
/*
* UniStrlen: Return the length of a string (in 16 bit Unicode chars not bytes)
*/
static inline size_t UniStrlen(const wchar_t *ucs1)
{
int i = 0;
while (*ucs1++)
i++;
return i;
}
/*
* UniStrnlen: Return the length (in 16 bit Unicode chars not bytes) of a
* string (length limited)
*/
static inline size_t UniStrnlen(const wchar_t *ucs1, int maxlen)
{
int i = 0;
while (*ucs1++) {
i++;
if (i >= maxlen)
break;
}
return i;
}
/*
* UniStrncat: Concatenate length limited string
*/
static inline wchar_t *UniStrncat(wchar_t *ucs1, const wchar_t *ucs2, size_t n)
{
wchar_t *anchor = ucs1; /* save pointer to string 1 */
while (*ucs1++)
/*NULL*/;
ucs1--; /* point to null terminator of s1 */
while (n-- && (*ucs1 = *ucs2)) { /* copy s2 after s1 */
ucs1++;
ucs2++;
}
*ucs1 = 0; /* Null terminate the result */
return anchor;
}
/*
* UniStrncmp: Compare length limited string
*/
static inline int UniStrncmp(const wchar_t *ucs1, const wchar_t *ucs2, size_t n)
{
if (!n)
return 0; /* Null strings are equal */
while ((*ucs1 == *ucs2) && *ucs1 && --n) {
ucs1++;
ucs2++;
}
return (int)*ucs1 - (int)*ucs2;
}
/*
* UniStrncmp_le: Compare length limited string - native to little-endian
*/
static inline int
UniStrncmp_le(const wchar_t *ucs1, const wchar_t *ucs2, size_t n)
{
if (!n)
return 0; /* Null strings are equal */
while ((*ucs1 == __le16_to_cpu(*ucs2)) && *ucs1 && --n) {
ucs1++;
ucs2++;
}
return (int)*ucs1 - (int)__le16_to_cpu(*ucs2);
}
/*
* UniStrncpy: Copy length limited string with pad
*/
static inline wchar_t *UniStrncpy(wchar_t *ucs1, const wchar_t *ucs2, size_t n)
{
wchar_t *anchor = ucs1;
while (n-- && *ucs2) /* Copy the strings */
*ucs1++ = *ucs2++;
n++;
while (n--) /* Pad with nulls */
*ucs1++ = 0;
return anchor;
}
/*
* UniStrncpy_le: Copy length limited string with pad to little-endian
*/
static inline wchar_t *UniStrncpy_le(wchar_t *ucs1, const wchar_t *ucs2, size_t n)
{
wchar_t *anchor = ucs1;
while (n-- && *ucs2) /* Copy the strings */
*ucs1++ = __le16_to_cpu(*ucs2++);
n++;
while (n--) /* Pad with nulls */
*ucs1++ = 0;
return anchor;
}
/*
* UniStrstr: Find a string in a string
*
* Returns:
* Address of first match found
* NULL if no matching string is found
*/
static inline wchar_t *UniStrstr(const wchar_t *ucs1, const wchar_t *ucs2)
{
const wchar_t *anchor1 = ucs1;
const wchar_t *anchor2 = ucs2;
while (*ucs1) {
if (*ucs1 == *ucs2) {
/* Partial match found */
ucs1++;
ucs2++;
} else {
if (!*ucs2) /* Match found */
return (wchar_t *)anchor1;
ucs1 = ++anchor1; /* No match */
ucs2 = anchor2;
}
}
if (!*ucs2) /* Both end together */
return (wchar_t *)anchor1; /* Match found */
return NULL; /* No match */
}
#ifndef UNIUPR_NOUPPER
/*
* UniToupper: Convert a unicode character to upper case
*/
static inline wchar_t UniToupper(register wchar_t uc)
{
register const struct UniCaseRange *rp;
if (uc < sizeof(SmbUniUpperTable)) {
/* Latin characters */
return uc + SmbUniUpperTable[uc]; /* Use base tables */
}
rp = SmbUniUpperRange; /* Use range tables */
while (rp->start) {
if (uc < rp->start) /* Before start of range */
return uc; /* Uppercase = input */
if (uc <= rp->end) /* In range */
return uc + rp->table[uc - rp->start];
rp++; /* Try next range */
}
return uc; /* Past last range */
}
/*
* UniStrupr: Upper case a unicode string
*/
static inline __le16 *UniStrupr(register __le16 *upin)
{
register __le16 *up;
up = upin;
while (*up) { /* For all characters */
*up = cpu_to_le16(UniToupper(le16_to_cpu(*up)));
up++;
}
return upin; /* Return input pointer */
}
#endif /* UNIUPR_NOUPPER */
#ifndef UNIUPR_NOLOWER
/*
* UniTolower: Convert a unicode character to lower case
*/
static inline wchar_t UniTolower(register wchar_t uc)
{
register const struct UniCaseRange *rp;
if (uc < sizeof(CifsUniLowerTable)) {
/* Latin characters */
return uc + CifsUniLowerTable[uc]; /* Use base tables */
}
rp = CifsUniLowerRange; /* Use range tables */
while (rp->start) {
if (uc < rp->start) /* Before start of range */
return uc; /* Uppercase = input */
if (uc <= rp->end) /* In range */
return uc + rp->table[uc - rp->start];
rp++; /* Try next range */
}
return uc; /* Past last range */
}
/*
* UniStrlwr: Lower case a unicode string
*/
static inline wchar_t *UniStrlwr(register wchar_t *upin)
{
register wchar_t *up;
up = upin;
while (*up) { /* For all characters */
*up = UniTolower(*up);
up++;
}
return upin; /* Return input pointer */
}
#endif
#endif /* _CIFS_UNICODE_H */