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Diffstat (limited to 'fs/ntfs/unistr.c')
| -rw-r--r-- | fs/ntfs/unistr.c | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/fs/ntfs/unistr.c b/fs/ntfs/unistr.c new file mode 100644 index 000000000..a6b6c64f1 --- /dev/null +++ b/fs/ntfs/unistr.c @@ -0,0 +1,384 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * unistr.c - NTFS Unicode string handling. Part of the Linux-NTFS project. + * + * Copyright (c) 2001-2006 Anton Altaparmakov + */ + +#include <linux/slab.h> + +#include "types.h" +#include "debug.h" +#include "ntfs.h" + +/* + * IMPORTANT + * ========= + * + * All these routines assume that the Unicode characters are in little endian + * encoding inside the strings!!! + */ + +/* + * This is used by the name collation functions to quickly determine what + * characters are (in)valid. + */ +static const u8 legal_ansi_char_array[0x40] = { + 0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, + 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, + + 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, + 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, + + 0x17, 0x07, 0x18, 0x17, 0x17, 0x17, 0x17, 0x17, + 0x17, 0x17, 0x18, 0x16, 0x16, 0x17, 0x07, 0x00, + + 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, + 0x17, 0x17, 0x04, 0x16, 0x18, 0x16, 0x18, 0x18, +}; + +/** + * ntfs_are_names_equal - compare two Unicode names for equality + * @s1: name to compare to @s2 + * @s1_len: length in Unicode characters of @s1 + * @s2: name to compare to @s1 + * @s2_len: length in Unicode characters of @s2 + * @ic: ignore case bool + * @upcase: upcase table (only if @ic == IGNORE_CASE) + * @upcase_size: length in Unicode characters of @upcase (if present) + * + * Compare the names @s1 and @s2 and return 'true' (1) if the names are + * identical, or 'false' (0) if they are not identical. If @ic is IGNORE_CASE, + * the @upcase table is used to performa a case insensitive comparison. + */ +bool ntfs_are_names_equal(const ntfschar *s1, size_t s1_len, + const ntfschar *s2, size_t s2_len, const IGNORE_CASE_BOOL ic, + const ntfschar *upcase, const u32 upcase_size) +{ + if (s1_len != s2_len) + return false; + if (ic == CASE_SENSITIVE) + return !ntfs_ucsncmp(s1, s2, s1_len); + return !ntfs_ucsncasecmp(s1, s2, s1_len, upcase, upcase_size); +} + +/** + * ntfs_collate_names - collate two Unicode names + * @name1: first Unicode name to compare + * @name2: second Unicode name to compare + * @err_val: if @name1 contains an invalid character return this value + * @ic: either CASE_SENSITIVE or IGNORE_CASE + * @upcase: upcase table (ignored if @ic is CASE_SENSITIVE) + * @upcase_len: upcase table size (ignored if @ic is CASE_SENSITIVE) + * + * ntfs_collate_names collates two Unicode names and returns: + * + * -1 if the first name collates before the second one, + * 0 if the names match, + * 1 if the second name collates before the first one, or + * @err_val if an invalid character is found in @name1 during the comparison. + * + * The following characters are considered invalid: '"', '*', '<', '>' and '?'. + */ +int ntfs_collate_names(const ntfschar *name1, const u32 name1_len, + const ntfschar *name2, const u32 name2_len, + const int err_val, const IGNORE_CASE_BOOL ic, + const ntfschar *upcase, const u32 upcase_len) +{ + u32 cnt, min_len; + u16 c1, c2; + + min_len = name1_len; + if (name1_len > name2_len) + min_len = name2_len; + for (cnt = 0; cnt < min_len; ++cnt) { + c1 = le16_to_cpu(*name1++); + c2 = le16_to_cpu(*name2++); + if (ic) { + if (c1 < upcase_len) + c1 = le16_to_cpu(upcase[c1]); + if (c2 < upcase_len) + c2 = le16_to_cpu(upcase[c2]); + } + if (c1 < 64 && legal_ansi_char_array[c1] & 8) + return err_val; + if (c1 < c2) + return -1; + if (c1 > c2) + return 1; + } + if (name1_len < name2_len) + return -1; + if (name1_len == name2_len) + return 0; + /* name1_len > name2_len */ + c1 = le16_to_cpu(*name1); + if (c1 < 64 && legal_ansi_char_array[c1] & 8) + return err_val; + return 1; +} + +/** + * ntfs_ucsncmp - compare two little endian Unicode strings + * @s1: first string + * @s2: second string + * @n: maximum unicode characters to compare + * + * Compare the first @n characters of the Unicode strings @s1 and @s2, + * The strings in little endian format and appropriate le16_to_cpu() + * conversion is performed on non-little endian machines. + * + * The function returns an integer less than, equal to, or greater than zero + * if @s1 (or the first @n Unicode characters thereof) is found, respectively, + * to be less than, to match, or be greater than @s2. + */ +int ntfs_ucsncmp(const ntfschar *s1, const ntfschar *s2, size_t n) +{ + u16 c1, c2; + size_t i; + + for (i = 0; i < n; ++i) { + c1 = le16_to_cpu(s1[i]); + c2 = le16_to_cpu(s2[i]); + if (c1 < c2) + return -1; + if (c1 > c2) + return 1; + if (!c1) + break; + } + return 0; +} + +/** + * ntfs_ucsncasecmp - compare two little endian Unicode strings, ignoring case + * @s1: first string + * @s2: second string + * @n: maximum unicode characters to compare + * @upcase: upcase table + * @upcase_size: upcase table size in Unicode characters + * + * Compare the first @n characters of the Unicode strings @s1 and @s2, + * ignoring case. The strings in little endian format and appropriate + * le16_to_cpu() conversion is performed on non-little endian machines. + * + * Each character is uppercased using the @upcase table before the comparison. + * + * The function returns an integer less than, equal to, or greater than zero + * if @s1 (or the first @n Unicode characters thereof) is found, respectively, + * to be less than, to match, or be greater than @s2. + */ +int ntfs_ucsncasecmp(const ntfschar *s1, const ntfschar *s2, size_t n, + const ntfschar *upcase, const u32 upcase_size) +{ + size_t i; + u16 c1, c2; + + for (i = 0; i < n; ++i) { + if ((c1 = le16_to_cpu(s1[i])) < upcase_size) + c1 = le16_to_cpu(upcase[c1]); + if ((c2 = le16_to_cpu(s2[i])) < upcase_size) + c2 = le16_to_cpu(upcase[c2]); + if (c1 < c2) + return -1; + if (c1 > c2) + return 1; + if (!c1) + break; + } + return 0; +} + +void ntfs_upcase_name(ntfschar *name, u32 name_len, const ntfschar *upcase, + const u32 upcase_len) +{ + u32 i; + u16 u; + + for (i = 0; i < name_len; i++) + if ((u = le16_to_cpu(name[i])) < upcase_len) + name[i] = upcase[u]; +} + +void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr, + const ntfschar *upcase, const u32 upcase_len) +{ + ntfs_upcase_name((ntfschar*)&file_name_attr->file_name, + file_name_attr->file_name_length, upcase, upcase_len); +} + +int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1, + FILE_NAME_ATTR *file_name_attr2, + const int err_val, const IGNORE_CASE_BOOL ic, + const ntfschar *upcase, const u32 upcase_len) +{ + return ntfs_collate_names((ntfschar*)&file_name_attr1->file_name, + file_name_attr1->file_name_length, + (ntfschar*)&file_name_attr2->file_name, + file_name_attr2->file_name_length, + err_val, ic, upcase, upcase_len); +} + +/** + * ntfs_nlstoucs - convert NLS string to little endian Unicode string + * @vol: ntfs volume which we are working with + * @ins: input NLS string buffer + * @ins_len: length of input string in bytes + * @outs: on return contains the allocated output Unicode string buffer + * + * Convert the input string @ins, which is in whatever format the loaded NLS + * map dictates, into a little endian, 2-byte Unicode string. + * + * This function allocates the string and the caller is responsible for + * calling kmem_cache_free(ntfs_name_cache, *@outs); when finished with it. + * + * On success the function returns the number of Unicode characters written to + * the output string *@outs (>= 0), not counting the terminating Unicode NULL + * character. *@outs is set to the allocated output string buffer. + * + * On error, a negative number corresponding to the error code is returned. In + * that case the output string is not allocated. Both *@outs and *@outs_len + * are then undefined. + * + * This might look a bit odd due to fast path optimization... + */ +int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins, + const int ins_len, ntfschar **outs) +{ + struct nls_table *nls = vol->nls_map; + ntfschar *ucs; + wchar_t wc; + int i, o, wc_len; + + /* We do not trust outside sources. */ + if (likely(ins)) { + ucs = kmem_cache_alloc(ntfs_name_cache, GFP_NOFS); + if (likely(ucs)) { + for (i = o = 0; i < ins_len; i += wc_len) { + wc_len = nls->char2uni(ins + i, ins_len - i, + &wc); + if (likely(wc_len >= 0 && + o < NTFS_MAX_NAME_LEN)) { + if (likely(wc)) { + ucs[o++] = cpu_to_le16(wc); + continue; + } /* else if (!wc) */ + break; + } /* else if (wc_len < 0 || + o >= NTFS_MAX_NAME_LEN) */ + goto name_err; + } + ucs[o] = 0; + *outs = ucs; + return o; + } /* else if (!ucs) */ + ntfs_error(vol->sb, "Failed to allocate buffer for converted " + "name from ntfs_name_cache."); + return -ENOMEM; + } /* else if (!ins) */ + ntfs_error(vol->sb, "Received NULL pointer."); + return -EINVAL; +name_err: + kmem_cache_free(ntfs_name_cache, ucs); + if (wc_len < 0) { + ntfs_error(vol->sb, "Name using character set %s contains " + "characters that cannot be converted to " + "Unicode.", nls->charset); + i = -EILSEQ; + } else /* if (o >= NTFS_MAX_NAME_LEN) */ { + ntfs_error(vol->sb, "Name is too long (maximum length for a " + "name on NTFS is %d Unicode characters.", + NTFS_MAX_NAME_LEN); + i = -ENAMETOOLONG; + } + return i; +} + +/** + * ntfs_ucstonls - convert little endian Unicode string to NLS string + * @vol: ntfs volume which we are working with + * @ins: input Unicode string buffer + * @ins_len: length of input string in Unicode characters + * @outs: on return contains the (allocated) output NLS string buffer + * @outs_len: length of output string buffer in bytes + * + * Convert the input little endian, 2-byte Unicode string @ins, of length + * @ins_len into the string format dictated by the loaded NLS. + * + * If *@outs is NULL, this function allocates the string and the caller is + * responsible for calling kfree(*@outs); when finished with it. In this case + * @outs_len is ignored and can be 0. + * + * On success the function returns the number of bytes written to the output + * string *@outs (>= 0), not counting the terminating NULL byte. If the output + * string buffer was allocated, *@outs is set to it. + * + * On error, a negative number corresponding to the error code is returned. In + * that case the output string is not allocated. The contents of *@outs are + * then undefined. + * + * This might look a bit odd due to fast path optimization... + */ +int ntfs_ucstonls(const ntfs_volume *vol, const ntfschar *ins, + const int ins_len, unsigned char **outs, int outs_len) +{ + struct nls_table *nls = vol->nls_map; + unsigned char *ns; + int i, o, ns_len, wc; + + /* We don't trust outside sources. */ + if (ins) { + ns = *outs; + ns_len = outs_len; + if (ns && !ns_len) { + wc = -ENAMETOOLONG; + goto conversion_err; + } + if (!ns) { + ns_len = ins_len * NLS_MAX_CHARSET_SIZE; + ns = kmalloc(ns_len + 1, GFP_NOFS); + if (!ns) + goto mem_err_out; + } + for (i = o = 0; i < ins_len; i++) { +retry: wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o, + ns_len - o); + if (wc > 0) { + o += wc; + continue; + } else if (!wc) + break; + else if (wc == -ENAMETOOLONG && ns != *outs) { + unsigned char *tc; + /* Grow in multiples of 64 bytes. */ + tc = kmalloc((ns_len + 64) & + ~63, GFP_NOFS); + if (tc) { + memcpy(tc, ns, ns_len); + ns_len = ((ns_len + 64) & ~63) - 1; + kfree(ns); + ns = tc; + goto retry; + } /* No memory so goto conversion_error; */ + } /* wc < 0, real error. */ + goto conversion_err; + } + ns[o] = 0; + *outs = ns; + return o; + } /* else (!ins) */ + ntfs_error(vol->sb, "Received NULL pointer."); + return -EINVAL; +conversion_err: + ntfs_error(vol->sb, "Unicode name contains characters that cannot be " + "converted to character set %s. You might want to " + "try to use the mount option nls=utf8.", nls->charset); + if (ns != *outs) + kfree(ns); + if (wc != -ENAMETOOLONG) + wc = -EILSEQ; + return wc; +mem_err_out: + ntfs_error(vol->sb, "Failed to allocate name!"); + return -ENOMEM; +} |