1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * unistr.c - NTFS Unicode string handling. Part of the Linux-NTFS project. |
4 | * |
5 | * Copyright (c) 2001-2006 Anton Altaparmakov |
6 | */ |
7 | |
8 | #include <linux/slab.h> |
9 | |
10 | #include "types.h" |
11 | #include "debug.h" |
12 | #include "ntfs.h" |
13 | |
14 | /* |
15 | * IMPORTANT |
16 | * ========= |
17 | * |
18 | * All these routines assume that the Unicode characters are in little endian |
19 | * encoding inside the strings!!! |
20 | */ |
21 | |
22 | /* |
23 | * This is used by the name collation functions to quickly determine what |
24 | * characters are (in)valid. |
25 | */ |
26 | static const u8 legal_ansi_char_array[0x40] = { |
27 | 0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, |
28 | 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, |
29 | |
30 | 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, |
31 | 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, |
32 | |
33 | 0x17, 0x07, 0x18, 0x17, 0x17, 0x17, 0x17, 0x17, |
34 | 0x17, 0x17, 0x18, 0x16, 0x16, 0x17, 0x07, 0x00, |
35 | |
36 | 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, |
37 | 0x17, 0x17, 0x04, 0x16, 0x18, 0x16, 0x18, 0x18, |
38 | }; |
39 | |
40 | /** |
41 | * ntfs_are_names_equal - compare two Unicode names for equality |
42 | * @s1: name to compare to @s2 |
43 | * @s1_len: length in Unicode characters of @s1 |
44 | * @s2: name to compare to @s1 |
45 | * @s2_len: length in Unicode characters of @s2 |
46 | * @ic: ignore case bool |
47 | * @upcase: upcase table (only if @ic == IGNORE_CASE) |
48 | * @upcase_size: length in Unicode characters of @upcase (if present) |
49 | * |
50 | * Compare the names @s1 and @s2 and return 'true' (1) if the names are |
51 | * identical, or 'false' (0) if they are not identical. If @ic is IGNORE_CASE, |
52 | * the @upcase table is used to performa a case insensitive comparison. |
53 | */ |
54 | bool ntfs_are_names_equal(const ntfschar *s1, size_t s1_len, |
55 | const ntfschar *s2, size_t s2_len, const IGNORE_CASE_BOOL ic, |
56 | const ntfschar *upcase, const u32 upcase_size) |
57 | { |
58 | if (s1_len != s2_len) |
59 | return false; |
60 | if (ic == CASE_SENSITIVE) |
61 | return !ntfs_ucsncmp(s1, s2, n: s1_len); |
62 | return !ntfs_ucsncasecmp(s1, s2, n: s1_len, upcase, upcase_size); |
63 | } |
64 | |
65 | /** |
66 | * ntfs_collate_names - collate two Unicode names |
67 | * @name1: first Unicode name to compare |
68 | * @name2: second Unicode name to compare |
69 | * @err_val: if @name1 contains an invalid character return this value |
70 | * @ic: either CASE_SENSITIVE or IGNORE_CASE |
71 | * @upcase: upcase table (ignored if @ic is CASE_SENSITIVE) |
72 | * @upcase_len: upcase table size (ignored if @ic is CASE_SENSITIVE) |
73 | * |
74 | * ntfs_collate_names collates two Unicode names and returns: |
75 | * |
76 | * -1 if the first name collates before the second one, |
77 | * 0 if the names match, |
78 | * 1 if the second name collates before the first one, or |
79 | * @err_val if an invalid character is found in @name1 during the comparison. |
80 | * |
81 | * The following characters are considered invalid: '"', '*', '<', '>' and '?'. |
82 | */ |
83 | int ntfs_collate_names(const ntfschar *name1, const u32 name1_len, |
84 | const ntfschar *name2, const u32 name2_len, |
85 | const int err_val, const IGNORE_CASE_BOOL ic, |
86 | const ntfschar *upcase, const u32 upcase_len) |
87 | { |
88 | u32 cnt, min_len; |
89 | u16 c1, c2; |
90 | |
91 | min_len = name1_len; |
92 | if (name1_len > name2_len) |
93 | min_len = name2_len; |
94 | for (cnt = 0; cnt < min_len; ++cnt) { |
95 | c1 = le16_to_cpu(*name1++); |
96 | c2 = le16_to_cpu(*name2++); |
97 | if (ic) { |
98 | if (c1 < upcase_len) |
99 | c1 = le16_to_cpu(upcase[c1]); |
100 | if (c2 < upcase_len) |
101 | c2 = le16_to_cpu(upcase[c2]); |
102 | } |
103 | if (c1 < 64 && legal_ansi_char_array[c1] & 8) |
104 | return err_val; |
105 | if (c1 < c2) |
106 | return -1; |
107 | if (c1 > c2) |
108 | return 1; |
109 | } |
110 | if (name1_len < name2_len) |
111 | return -1; |
112 | if (name1_len == name2_len) |
113 | return 0; |
114 | /* name1_len > name2_len */ |
115 | c1 = le16_to_cpu(*name1); |
116 | if (c1 < 64 && legal_ansi_char_array[c1] & 8) |
117 | return err_val; |
118 | return 1; |
119 | } |
120 | |
121 | /** |
122 | * ntfs_ucsncmp - compare two little endian Unicode strings |
123 | * @s1: first string |
124 | * @s2: second string |
125 | * @n: maximum unicode characters to compare |
126 | * |
127 | * Compare the first @n characters of the Unicode strings @s1 and @s2, |
128 | * The strings in little endian format and appropriate le16_to_cpu() |
129 | * conversion is performed on non-little endian machines. |
130 | * |
131 | * The function returns an integer less than, equal to, or greater than zero |
132 | * if @s1 (or the first @n Unicode characters thereof) is found, respectively, |
133 | * to be less than, to match, or be greater than @s2. |
134 | */ |
135 | int ntfs_ucsncmp(const ntfschar *s1, const ntfschar *s2, size_t n) |
136 | { |
137 | u16 c1, c2; |
138 | size_t i; |
139 | |
140 | for (i = 0; i < n; ++i) { |
141 | c1 = le16_to_cpu(s1[i]); |
142 | c2 = le16_to_cpu(s2[i]); |
143 | if (c1 < c2) |
144 | return -1; |
145 | if (c1 > c2) |
146 | return 1; |
147 | if (!c1) |
148 | break; |
149 | } |
150 | return 0; |
151 | } |
152 | |
153 | /** |
154 | * ntfs_ucsncasecmp - compare two little endian Unicode strings, ignoring case |
155 | * @s1: first string |
156 | * @s2: second string |
157 | * @n: maximum unicode characters to compare |
158 | * @upcase: upcase table |
159 | * @upcase_size: upcase table size in Unicode characters |
160 | * |
161 | * Compare the first @n characters of the Unicode strings @s1 and @s2, |
162 | * ignoring case. The strings in little endian format and appropriate |
163 | * le16_to_cpu() conversion is performed on non-little endian machines. |
164 | * |
165 | * Each character is uppercased using the @upcase table before the comparison. |
166 | * |
167 | * The function returns an integer less than, equal to, or greater than zero |
168 | * if @s1 (or the first @n Unicode characters thereof) is found, respectively, |
169 | * to be less than, to match, or be greater than @s2. |
170 | */ |
171 | int ntfs_ucsncasecmp(const ntfschar *s1, const ntfschar *s2, size_t n, |
172 | const ntfschar *upcase, const u32 upcase_size) |
173 | { |
174 | size_t i; |
175 | u16 c1, c2; |
176 | |
177 | for (i = 0; i < n; ++i) { |
178 | if ((c1 = le16_to_cpu(s1[i])) < upcase_size) |
179 | c1 = le16_to_cpu(upcase[c1]); |
180 | if ((c2 = le16_to_cpu(s2[i])) < upcase_size) |
181 | c2 = le16_to_cpu(upcase[c2]); |
182 | if (c1 < c2) |
183 | return -1; |
184 | if (c1 > c2) |
185 | return 1; |
186 | if (!c1) |
187 | break; |
188 | } |
189 | return 0; |
190 | } |
191 | |
192 | void ntfs_upcase_name(ntfschar *name, u32 name_len, const ntfschar *upcase, |
193 | const u32 upcase_len) |
194 | { |
195 | u32 i; |
196 | u16 u; |
197 | |
198 | for (i = 0; i < name_len; i++) |
199 | if ((u = le16_to_cpu(name[i])) < upcase_len) |
200 | name[i] = upcase[u]; |
201 | } |
202 | |
203 | void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr, |
204 | const ntfschar *upcase, const u32 upcase_len) |
205 | { |
206 | ntfs_upcase_name(name: (ntfschar*)&file_name_attr->file_name, |
207 | name_len: file_name_attr->file_name_length, upcase, upcase_len); |
208 | } |
209 | |
210 | int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1, |
211 | FILE_NAME_ATTR *file_name_attr2, |
212 | const int err_val, const IGNORE_CASE_BOOL ic, |
213 | const ntfschar *upcase, const u32 upcase_len) |
214 | { |
215 | return ntfs_collate_names(name1: (ntfschar*)&file_name_attr1->file_name, |
216 | name1_len: file_name_attr1->file_name_length, |
217 | name2: (ntfschar*)&file_name_attr2->file_name, |
218 | name2_len: file_name_attr2->file_name_length, |
219 | err_val, ic, upcase, upcase_len); |
220 | } |
221 | |
222 | /** |
223 | * ntfs_nlstoucs - convert NLS string to little endian Unicode string |
224 | * @vol: ntfs volume which we are working with |
225 | * @ins: input NLS string buffer |
226 | * @ins_len: length of input string in bytes |
227 | * @outs: on return contains the allocated output Unicode string buffer |
228 | * |
229 | * Convert the input string @ins, which is in whatever format the loaded NLS |
230 | * map dictates, into a little endian, 2-byte Unicode string. |
231 | * |
232 | * This function allocates the string and the caller is responsible for |
233 | * calling kmem_cache_free(ntfs_name_cache, *@outs); when finished with it. |
234 | * |
235 | * On success the function returns the number of Unicode characters written to |
236 | * the output string *@outs (>= 0), not counting the terminating Unicode NULL |
237 | * character. *@outs is set to the allocated output string buffer. |
238 | * |
239 | * On error, a negative number corresponding to the error code is returned. In |
240 | * that case the output string is not allocated. Both *@outs and *@outs_len |
241 | * are then undefined. |
242 | * |
243 | * This might look a bit odd due to fast path optimization... |
244 | */ |
245 | int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins, |
246 | const int ins_len, ntfschar **outs) |
247 | { |
248 | struct nls_table *nls = vol->nls_map; |
249 | ntfschar *ucs; |
250 | wchar_t wc; |
251 | int i, o, wc_len; |
252 | |
253 | /* We do not trust outside sources. */ |
254 | if (likely(ins)) { |
255 | ucs = kmem_cache_alloc(cachep: ntfs_name_cache, GFP_NOFS); |
256 | if (likely(ucs)) { |
257 | for (i = o = 0; i < ins_len; i += wc_len) { |
258 | wc_len = nls->char2uni(ins + i, ins_len - i, |
259 | &wc); |
260 | if (likely(wc_len >= 0 && |
261 | o < NTFS_MAX_NAME_LEN)) { |
262 | if (likely(wc)) { |
263 | ucs[o++] = cpu_to_le16(wc); |
264 | continue; |
265 | } /* else if (!wc) */ |
266 | break; |
267 | } /* else if (wc_len < 0 || |
268 | o >= NTFS_MAX_NAME_LEN) */ |
269 | goto name_err; |
270 | } |
271 | ucs[o] = 0; |
272 | *outs = ucs; |
273 | return o; |
274 | } /* else if (!ucs) */ |
275 | ntfs_error(vol->sb, "Failed to allocate buffer for converted " |
276 | "name from ntfs_name_cache." ); |
277 | return -ENOMEM; |
278 | } /* else if (!ins) */ |
279 | ntfs_error(vol->sb, "Received NULL pointer." ); |
280 | return -EINVAL; |
281 | name_err: |
282 | kmem_cache_free(s: ntfs_name_cache, objp: ucs); |
283 | if (wc_len < 0) { |
284 | ntfs_error(vol->sb, "Name using character set %s contains " |
285 | "characters that cannot be converted to " |
286 | "Unicode." , nls->charset); |
287 | i = -EILSEQ; |
288 | } else /* if (o >= NTFS_MAX_NAME_LEN) */ { |
289 | ntfs_error(vol->sb, "Name is too long (maximum length for a " |
290 | "name on NTFS is %d Unicode characters." , |
291 | NTFS_MAX_NAME_LEN); |
292 | i = -ENAMETOOLONG; |
293 | } |
294 | return i; |
295 | } |
296 | |
297 | /** |
298 | * ntfs_ucstonls - convert little endian Unicode string to NLS string |
299 | * @vol: ntfs volume which we are working with |
300 | * @ins: input Unicode string buffer |
301 | * @ins_len: length of input string in Unicode characters |
302 | * @outs: on return contains the (allocated) output NLS string buffer |
303 | * @outs_len: length of output string buffer in bytes |
304 | * |
305 | * Convert the input little endian, 2-byte Unicode string @ins, of length |
306 | * @ins_len into the string format dictated by the loaded NLS. |
307 | * |
308 | * If *@outs is NULL, this function allocates the string and the caller is |
309 | * responsible for calling kfree(*@outs); when finished with it. In this case |
310 | * @outs_len is ignored and can be 0. |
311 | * |
312 | * On success the function returns the number of bytes written to the output |
313 | * string *@outs (>= 0), not counting the terminating NULL byte. If the output |
314 | * string buffer was allocated, *@outs is set to it. |
315 | * |
316 | * On error, a negative number corresponding to the error code is returned. In |
317 | * that case the output string is not allocated. The contents of *@outs are |
318 | * then undefined. |
319 | * |
320 | * This might look a bit odd due to fast path optimization... |
321 | */ |
322 | int ntfs_ucstonls(const ntfs_volume *vol, const ntfschar *ins, |
323 | const int ins_len, unsigned char **outs, int outs_len) |
324 | { |
325 | struct nls_table *nls = vol->nls_map; |
326 | unsigned char *ns; |
327 | int i, o, ns_len, wc; |
328 | |
329 | /* We don't trust outside sources. */ |
330 | if (ins) { |
331 | ns = *outs; |
332 | ns_len = outs_len; |
333 | if (ns && !ns_len) { |
334 | wc = -ENAMETOOLONG; |
335 | goto conversion_err; |
336 | } |
337 | if (!ns) { |
338 | ns_len = ins_len * NLS_MAX_CHARSET_SIZE; |
339 | ns = kmalloc(size: ns_len + 1, GFP_NOFS); |
340 | if (!ns) |
341 | goto mem_err_out; |
342 | } |
343 | for (i = o = 0; i < ins_len; i++) { |
344 | retry: wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o, |
345 | ns_len - o); |
346 | if (wc > 0) { |
347 | o += wc; |
348 | continue; |
349 | } else if (!wc) |
350 | break; |
351 | else if (wc == -ENAMETOOLONG && ns != *outs) { |
352 | unsigned char *tc; |
353 | /* Grow in multiples of 64 bytes. */ |
354 | tc = kmalloc(size: (ns_len + 64) & |
355 | ~63, GFP_NOFS); |
356 | if (tc) { |
357 | memcpy(tc, ns, ns_len); |
358 | ns_len = ((ns_len + 64) & ~63) - 1; |
359 | kfree(objp: ns); |
360 | ns = tc; |
361 | goto retry; |
362 | } /* No memory so goto conversion_error; */ |
363 | } /* wc < 0, real error. */ |
364 | goto conversion_err; |
365 | } |
366 | ns[o] = 0; |
367 | *outs = ns; |
368 | return o; |
369 | } /* else (!ins) */ |
370 | ntfs_error(vol->sb, "Received NULL pointer." ); |
371 | return -EINVAL; |
372 | conversion_err: |
373 | ntfs_error(vol->sb, "Unicode name contains characters that cannot be " |
374 | "converted to character set %s. You might want to " |
375 | "try to use the mount option nls=utf8." , nls->charset); |
376 | if (ns != *outs) |
377 | kfree(objp: ns); |
378 | if (wc != -ENAMETOOLONG) |
379 | wc = -EILSEQ; |
380 | return wc; |
381 | mem_err_out: |
382 | ntfs_error(vol->sb, "Failed to allocate name!" ); |
383 | return -ENOMEM; |
384 | } |
385 | |