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-rw-r--r--fs/hfsplus/unicode.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c
new file mode 100644
index 000000000..73342c925
--- /dev/null
+++ b/fs/hfsplus/unicode.c
@@ -0,0 +1,520 @@
+// 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 non-Hangul unicode character. */
+static u16 *hfsplus_decompose_nonhangul(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);
+}
+
+/*
+ * Try to decompose a unicode character as Hangul. Return 0 if @uc is not
+ * precomposed Hangul, otherwise return the length of the decomposition.
+ *
+ * This function was adapted from sample code from the Unicode Standard
+ * Annex #15: Unicode Normalization Forms, version 3.2.0.
+ *
+ * Copyright (C) 1991-2018 Unicode, Inc. All rights reserved. Distributed
+ * under the Terms of Use in http://www.unicode.org/copyright.html.
+ */
+static int hfsplus_try_decompose_hangul(wchar_t uc, u16 *result)
+{
+ int index;
+ int l, v, t;
+
+ index = uc - Hangul_SBase;
+ if (index < 0 || index >= Hangul_SCount)
+ return 0;
+
+ l = Hangul_LBase + index / Hangul_NCount;
+ v = Hangul_VBase + (index % Hangul_NCount) / Hangul_TCount;
+ t = Hangul_TBase + index % Hangul_TCount;
+
+ result[0] = l;
+ result[1] = v;
+ if (t != Hangul_TBase) {
+ result[2] = t;
+ return 3;
+ }
+ return 2;
+}
+
+/* Decomposes a single unicode character. */
+static u16 *decompose_unichar(wchar_t uc, int *size, u16 *hangul_buffer)
+{
+ u16 *result;
+
+ /* Hangul is handled separately */
+ result = hangul_buffer;
+ *size = hfsplus_try_decompose_hangul(uc, result);
+ if (*size == 0)
+ result = hfsplus_decompose_nonhangul(uc, size);
+ return result;
+}
+
+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;
+ u16 dhangul[3];
+
+ 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, dhangul);
+ 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;
+ u16 dhangul[3];
+
+ 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, dhangul);
+ 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;
+ u16 dhangul_1[3], dhangul_2[3];
+
+ 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,
+ dhangul_1);
+ 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,
+ dhangul_2);
+ 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;
+}
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