| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/fs/hfsplus/unicode.c |
| * |
| * Copyright (C) 2001 |
| * Brad Boyer (flar@allandria.com) |
| * (C) 2003 Ardis Technologies <roman@ardistech.com> |
| * |
| * Handler routines for unicode strings |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/nls.h> |
| #include "hfsplus_fs.h" |
| #include "hfsplus_raw.h" |
| |
| /* Fold the case of a unicode char, given the 16 bit value */ |
| /* Returns folded char, or 0 if ignorable */ |
| static inline u16 case_fold(u16 c) |
| { |
| u16 tmp; |
| |
| tmp = hfsplus_case_fold_table[c >> 8]; |
| if (tmp) |
| tmp = hfsplus_case_fold_table[tmp + (c & 0xff)]; |
| else |
| tmp = c; |
| return tmp; |
| } |
| |
| /* Compare unicode strings, return values like normal strcmp */ |
| int hfsplus_strcasecmp(const struct hfsplus_unistr *s1, |
| const struct hfsplus_unistr *s2) |
| { |
| u16 len1, len2, c1, c2; |
| const hfsplus_unichr *p1, *p2; |
| |
| len1 = be16_to_cpu(s1->length); |
| len2 = be16_to_cpu(s2->length); |
| p1 = s1->unicode; |
| p2 = s2->unicode; |
| |
| while (1) { |
| c1 = c2 = 0; |
| |
| while (len1 && !c1) { |
| c1 = case_fold(be16_to_cpu(*p1)); |
| p1++; |
| len1--; |
| } |
| while (len2 && !c2) { |
| c2 = case_fold(be16_to_cpu(*p2)); |
| p2++; |
| len2--; |
| } |
| |
| if (c1 != c2) |
| return (c1 < c2) ? -1 : 1; |
| if (!c1 && !c2) |
| return 0; |
| } |
| } |
| |
| /* Compare names as a sequence of 16-bit unsigned integers */ |
| int hfsplus_strcmp(const struct hfsplus_unistr *s1, |
| const struct hfsplus_unistr *s2) |
| { |
| u16 len1, len2, c1, c2; |
| const hfsplus_unichr *p1, *p2; |
| int len; |
| |
| len1 = be16_to_cpu(s1->length); |
| len2 = be16_to_cpu(s2->length); |
| p1 = s1->unicode; |
| p2 = s2->unicode; |
| |
| for (len = min(len1, len2); len > 0; len--) { |
| c1 = be16_to_cpu(*p1); |
| c2 = be16_to_cpu(*p2); |
| if (c1 != c2) |
| return c1 < c2 ? -1 : 1; |
| p1++; |
| p2++; |
| } |
| |
| return len1 < len2 ? -1 : |
| len1 > len2 ? 1 : 0; |
| } |
| |
| |
| #define Hangul_SBase 0xac00 |
| #define Hangul_LBase 0x1100 |
| #define Hangul_VBase 0x1161 |
| #define Hangul_TBase 0x11a7 |
| #define Hangul_SCount 11172 |
| #define Hangul_LCount 19 |
| #define Hangul_VCount 21 |
| #define Hangul_TCount 28 |
| #define Hangul_NCount (Hangul_VCount * Hangul_TCount) |
| |
| |
| static u16 *hfsplus_compose_lookup(u16 *p, u16 cc) |
| { |
| int i, s, e; |
| |
| s = 1; |
| e = p[1]; |
| if (!e || cc < p[s * 2] || cc > p[e * 2]) |
| return NULL; |
| do { |
| i = (s + e) / 2; |
| if (cc > p[i * 2]) |
| s = i + 1; |
| else if (cc < p[i * 2]) |
| e = i - 1; |
| else |
| return hfsplus_compose_table + p[i * 2 + 1]; |
| } while (s <= e); |
| return NULL; |
| } |
| |
| int hfsplus_uni2asc(struct super_block *sb, |
| const struct hfsplus_unistr *ustr, |
| char *astr, int *len_p) |
| { |
| const hfsplus_unichr *ip; |
| struct nls_table *nls = HFSPLUS_SB(sb)->nls; |
| u8 *op; |
| u16 cc, c0, c1; |
| u16 *ce1, *ce2; |
| int i, len, ustrlen, res, compose; |
| |
| op = astr; |
| ip = ustr->unicode; |
| ustrlen = be16_to_cpu(ustr->length); |
| len = *len_p; |
| ce1 = NULL; |
| compose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags); |
| |
| while (ustrlen > 0) { |
| c0 = be16_to_cpu(*ip++); |
| ustrlen--; |
| /* search for single decomposed char */ |
| if (likely(compose)) |
| ce1 = hfsplus_compose_lookup(hfsplus_compose_table, c0); |
| if (ce1) |
| cc = ce1[0]; |
| else |
| cc = 0; |
| if (cc) { |
| /* start of a possibly decomposed Hangul char */ |
| if (cc != 0xffff) |
| goto done; |
| if (!ustrlen) |
| goto same; |
| c1 = be16_to_cpu(*ip) - Hangul_VBase; |
| if (c1 < Hangul_VCount) { |
| /* compose the Hangul char */ |
| cc = (c0 - Hangul_LBase) * Hangul_VCount; |
| cc = (cc + c1) * Hangul_TCount; |
| cc += Hangul_SBase; |
| ip++; |
| ustrlen--; |
| if (!ustrlen) |
| goto done; |
| c1 = be16_to_cpu(*ip) - Hangul_TBase; |
| if (c1 > 0 && c1 < Hangul_TCount) { |
| cc += c1; |
| ip++; |
| ustrlen--; |
| } |
| goto done; |
| } |
| } |
| while (1) { |
| /* main loop for common case of not composed chars */ |
| if (!ustrlen) |
| goto same; |
| c1 = be16_to_cpu(*ip); |
| if (likely(compose)) |
| ce1 = hfsplus_compose_lookup( |
| hfsplus_compose_table, c1); |
| if (ce1) |
| break; |
| switch (c0) { |
| case 0: |
| c0 = 0x2400; |
| break; |
| case '/': |
| c0 = ':'; |
| break; |
| } |
| res = nls->uni2char(c0, op, len); |
| if (res < 0) { |
| if (res == -ENAMETOOLONG) |
| goto out; |
| *op = '?'; |
| res = 1; |
| } |
| op += res; |
| len -= res; |
| c0 = c1; |
| ip++; |
| ustrlen--; |
| } |
| ce2 = hfsplus_compose_lookup(ce1, c0); |
| if (ce2) { |
| i = 1; |
| while (i < ustrlen) { |
| ce1 = hfsplus_compose_lookup(ce2, |
| be16_to_cpu(ip[i])); |
| if (!ce1) |
| break; |
| i++; |
| ce2 = ce1; |
| } |
| cc = ce2[0]; |
| if (cc) { |
| ip += i; |
| ustrlen -= i; |
| goto done; |
| } |
| } |
| same: |
| switch (c0) { |
| case 0: |
| cc = 0x2400; |
| break; |
| case '/': |
| cc = ':'; |
| break; |
| default: |
| cc = c0; |
| } |
| done: |
| res = nls->uni2char(cc, op, len); |
| if (res < 0) { |
| if (res == -ENAMETOOLONG) |
| goto out; |
| *op = '?'; |
| res = 1; |
| } |
| op += res; |
| len -= res; |
| } |
| res = 0; |
| out: |
| *len_p = (char *)op - astr; |
| return res; |
| } |
| |
| /* |
| * Convert one or more ASCII characters into a single unicode character. |
| * Returns the number of ASCII characters corresponding to the unicode char. |
| */ |
| static inline int asc2unichar(struct super_block *sb, const char *astr, int len, |
| wchar_t *uc) |
| { |
| int size = HFSPLUS_SB(sb)->nls->char2uni(astr, len, uc); |
| if (size <= 0) { |
| *uc = '?'; |
| size = 1; |
| } |
| switch (*uc) { |
| case 0x2400: |
| *uc = 0; |
| break; |
| case ':': |
| *uc = '/'; |
| break; |
| } |
| return size; |
| } |
| |
| /* Decomposes a single unicode character. */ |
| static inline u16 *decompose_unichar(wchar_t uc, int *size) |
| { |
| int off; |
| |
| off = hfsplus_decompose_table[(uc >> 12) & 0xf]; |
| if (off == 0 || off == 0xffff) |
| return NULL; |
| |
| off = hfsplus_decompose_table[off + ((uc >> 8) & 0xf)]; |
| if (!off) |
| return NULL; |
| |
| off = hfsplus_decompose_table[off + ((uc >> 4) & 0xf)]; |
| if (!off) |
| return NULL; |
| |
| off = hfsplus_decompose_table[off + (uc & 0xf)]; |
| *size = off & 3; |
| if (*size == 0) |
| return NULL; |
| return hfsplus_decompose_table + (off / 4); |
| } |
| |
| int hfsplus_asc2uni(struct super_block *sb, |
| struct hfsplus_unistr *ustr, int max_unistr_len, |
| const char *astr, int len) |
| { |
| int size, dsize, decompose; |
| u16 *dstr, outlen = 0; |
| wchar_t c; |
| |
| decompose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags); |
| while (outlen < max_unistr_len && len > 0) { |
| size = asc2unichar(sb, astr, len, &c); |
| |
| if (decompose) |
| dstr = decompose_unichar(c, &dsize); |
| else |
| dstr = NULL; |
| if (dstr) { |
| if (outlen + dsize > max_unistr_len) |
| break; |
| do { |
| ustr->unicode[outlen++] = cpu_to_be16(*dstr++); |
| } while (--dsize > 0); |
| } else |
| ustr->unicode[outlen++] = cpu_to_be16(c); |
| |
| astr += size; |
| len -= size; |
| } |
| ustr->length = cpu_to_be16(outlen); |
| if (len > 0) |
| return -ENAMETOOLONG; |
| return 0; |
| } |
| |
| /* |
| * Hash a string to an integer as appropriate for the HFS+ filesystem. |
| * Composed unicode characters are decomposed and case-folding is performed |
| * if the appropriate bits are (un)set on the superblock. |
| */ |
| int hfsplus_hash_dentry(const struct dentry *dentry, struct qstr *str) |
| { |
| struct super_block *sb = dentry->d_sb; |
| const char *astr; |
| const u16 *dstr; |
| int casefold, decompose, size, len; |
| unsigned long hash; |
| wchar_t c; |
| u16 c2; |
| |
| casefold = test_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags); |
| decompose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags); |
| hash = init_name_hash(dentry); |
| astr = str->name; |
| len = str->len; |
| while (len > 0) { |
| int dsize; |
| size = asc2unichar(sb, astr, len, &c); |
| astr += size; |
| len -= size; |
| |
| if (decompose) |
| dstr = decompose_unichar(c, &dsize); |
| else |
| dstr = NULL; |
| if (dstr) { |
| do { |
| c2 = *dstr++; |
| if (casefold) |
| c2 = case_fold(c2); |
| if (!casefold || c2) |
| hash = partial_name_hash(c2, hash); |
| } while (--dsize > 0); |
| } else { |
| c2 = c; |
| if (casefold) |
| c2 = case_fold(c2); |
| if (!casefold || c2) |
| hash = partial_name_hash(c2, hash); |
| } |
| } |
| str->hash = end_name_hash(hash); |
| |
| return 0; |
| } |
| |
| /* |
| * Compare strings with HFS+ filename ordering. |
| * Composed unicode characters are decomposed and case-folding is performed |
| * if the appropriate bits are (un)set on the superblock. |
| */ |
| int hfsplus_compare_dentry(const struct dentry *dentry, |
| unsigned int len, const char *str, const struct qstr *name) |
| { |
| struct super_block *sb = dentry->d_sb; |
| int casefold, decompose, size; |
| int dsize1, dsize2, len1, len2; |
| const u16 *dstr1, *dstr2; |
| const char *astr1, *astr2; |
| u16 c1, c2; |
| wchar_t c; |
| |
| casefold = test_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags); |
| decompose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags); |
| astr1 = str; |
| len1 = len; |
| astr2 = name->name; |
| len2 = name->len; |
| dsize1 = dsize2 = 0; |
| dstr1 = dstr2 = NULL; |
| |
| while (len1 > 0 && len2 > 0) { |
| if (!dsize1) { |
| size = asc2unichar(sb, astr1, len1, &c); |
| astr1 += size; |
| len1 -= size; |
| |
| if (decompose) |
| dstr1 = decompose_unichar(c, &dsize1); |
| if (!decompose || !dstr1) { |
| c1 = c; |
| dstr1 = &c1; |
| dsize1 = 1; |
| } |
| } |
| |
| if (!dsize2) { |
| size = asc2unichar(sb, astr2, len2, &c); |
| astr2 += size; |
| len2 -= size; |
| |
| if (decompose) |
| dstr2 = decompose_unichar(c, &dsize2); |
| if (!decompose || !dstr2) { |
| c2 = c; |
| dstr2 = &c2; |
| dsize2 = 1; |
| } |
| } |
| |
| c1 = *dstr1; |
| c2 = *dstr2; |
| if (casefold) { |
| c1 = case_fold(c1); |
| if (!c1) { |
| dstr1++; |
| dsize1--; |
| continue; |
| } |
| c2 = case_fold(c2); |
| if (!c2) { |
| dstr2++; |
| dsize2--; |
| continue; |
| } |
| } |
| if (c1 < c2) |
| return -1; |
| else if (c1 > c2) |
| return 1; |
| |
| dstr1++; |
| dsize1--; |
| dstr2++; |
| dsize2--; |
| } |
| |
| if (len1 < len2) |
| return -1; |
| if (len1 > len2) |
| return 1; |
| return 0; |
| } |