1 /*
2 * unicode.c
3 *
4 * PURPOSE
5 * Routines for converting between UTF-8 and OSTA Compressed Unicode.
6 * Also handles filename mangling
7 *
8 * DESCRIPTION
9 * OSTA Compressed Unicode is explained in the OSTA UDF specification.
10 * http://www.osta.org/
11 * UTF-8 is explained in the IETF RFC XXXX.
12 * ftp://ftp.internic.net/rfc/rfcxxxx.txt
13 *
14 * COPYRIGHT
15 * This file is distributed under the terms of the GNU General Public
16 * License (GPL). Copies of the GPL can be obtained from:
17 * ftp://prep.ai.mit.edu/pub/gnu/GPL
18 * Each contributing author retains all rights to their own work.
19 */
20
21 #include "udfdecl.h"
22
23 #include <linux/kernel.h>
24 #include <linux/string.h> /* for memset */
25 #include <linux/nls.h>
26 #include <linux/crc-itu-t.h>
27
28 #include "udf_sb.h"
29
30 static int udf_translate_to_linux(uint8_t *, uint8_t *, int, uint8_t *, int);
31
udf_char_to_ustr(struct ustr * dest,const uint8_t * src,int strlen)32 static int udf_char_to_ustr(struct ustr *dest, const uint8_t *src, int strlen)
33 {
34 if ((!dest) || (!src) || (!strlen) || (strlen > UDF_NAME_LEN - 2))
35 return 0;
36
37 memset(dest, 0, sizeof(struct ustr));
38 memcpy(dest->u_name, src, strlen);
39 dest->u_cmpID = 0x08;
40 dest->u_len = strlen;
41
42 return strlen;
43 }
44
45 /*
46 * udf_build_ustr
47 */
udf_build_ustr(struct ustr * dest,dstring * ptr,int size)48 int udf_build_ustr(struct ustr *dest, dstring *ptr, int size)
49 {
50 int usesize;
51
52 if (!dest || !ptr || !size)
53 return -1;
54 BUG_ON(size < 2);
55
56 usesize = min_t(size_t, ptr[size - 1], sizeof(dest->u_name));
57 usesize = min(usesize, size - 2);
58 dest->u_cmpID = ptr[0];
59 dest->u_len = usesize;
60 memcpy(dest->u_name, ptr + 1, usesize);
61 memset(dest->u_name + usesize, 0, sizeof(dest->u_name) - usesize);
62
63 return 0;
64 }
65
66 /*
67 * udf_build_ustr_exact
68 */
udf_build_ustr_exact(struct ustr * dest,dstring * ptr,int exactsize)69 static int udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize)
70 {
71 if ((!dest) || (!ptr) || (!exactsize))
72 return -1;
73
74 memset(dest, 0, sizeof(struct ustr));
75 dest->u_cmpID = ptr[0];
76 dest->u_len = exactsize - 1;
77 memcpy(dest->u_name, ptr + 1, exactsize - 1);
78
79 return 0;
80 }
81
82 /*
83 * udf_ocu_to_utf8
84 *
85 * PURPOSE
86 * Convert OSTA Compressed Unicode to the UTF-8 equivalent.
87 *
88 * PRE-CONDITIONS
89 * utf Pointer to UTF-8 output buffer.
90 * ocu Pointer to OSTA Compressed Unicode input buffer
91 * of size UDF_NAME_LEN bytes.
92 * both of type "struct ustr *"
93 *
94 * POST-CONDITIONS
95 * <return> Zero on success.
96 *
97 * HISTORY
98 * November 12, 1997 - Andrew E. Mileski
99 * Written, tested, and released.
100 */
udf_CS0toUTF8(struct ustr * utf_o,const struct ustr * ocu_i)101 int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i)
102 {
103 const uint8_t *ocu;
104 uint8_t cmp_id, ocu_len;
105 int i;
106
107 ocu_len = ocu_i->u_len;
108 if (ocu_len == 0) {
109 memset(utf_o, 0, sizeof(struct ustr));
110 return 0;
111 }
112
113 cmp_id = ocu_i->u_cmpID;
114 if (cmp_id != 8 && cmp_id != 16) {
115 memset(utf_o, 0, sizeof(struct ustr));
116 printk(KERN_ERR "udf: unknown compression code (%d) stri=%s\n",
117 cmp_id, ocu_i->u_name);
118 return 0;
119 }
120
121 ocu = ocu_i->u_name;
122 utf_o->u_len = 0;
123 for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) {
124
125 /* Expand OSTA compressed Unicode to Unicode */
126 uint32_t c = ocu[i++];
127 if (cmp_id == 16)
128 c = (c << 8) | ocu[i++];
129
130 /* Compress Unicode to UTF-8 */
131 if (c < 0x80U)
132 utf_o->u_name[utf_o->u_len++] = (uint8_t)c;
133 else if (c < 0x800U) {
134 utf_o->u_name[utf_o->u_len++] =
135 (uint8_t)(0xc0 | (c >> 6));
136 utf_o->u_name[utf_o->u_len++] =
137 (uint8_t)(0x80 | (c & 0x3f));
138 } else {
139 utf_o->u_name[utf_o->u_len++] =
140 (uint8_t)(0xe0 | (c >> 12));
141 utf_o->u_name[utf_o->u_len++] =
142 (uint8_t)(0x80 |
143 ((c >> 6) & 0x3f));
144 utf_o->u_name[utf_o->u_len++] =
145 (uint8_t)(0x80 | (c & 0x3f));
146 }
147 }
148 utf_o->u_cmpID = 8;
149
150 return utf_o->u_len;
151 }
152
153 /*
154 *
155 * udf_utf8_to_ocu
156 *
157 * PURPOSE
158 * Convert UTF-8 to the OSTA Compressed Unicode equivalent.
159 *
160 * DESCRIPTION
161 * This routine is only called by udf_lookup().
162 *
163 * PRE-CONDITIONS
164 * ocu Pointer to OSTA Compressed Unicode output
165 * buffer of size UDF_NAME_LEN bytes.
166 * utf Pointer to UTF-8 input buffer.
167 * utf_len Length of UTF-8 input buffer in bytes.
168 *
169 * POST-CONDITIONS
170 * <return> Zero on success.
171 *
172 * HISTORY
173 * November 12, 1997 - Andrew E. Mileski
174 * Written, tested, and released.
175 */
udf_UTF8toCS0(dstring * ocu,struct ustr * utf,int length)176 static int udf_UTF8toCS0(dstring *ocu, struct ustr *utf, int length)
177 {
178 unsigned c, i, max_val, utf_char;
179 int utf_cnt, u_len;
180
181 memset(ocu, 0, sizeof(dstring) * length);
182 ocu[0] = 8;
183 max_val = 0xffU;
184
185 try_again:
186 u_len = 0U;
187 utf_char = 0U;
188 utf_cnt = 0U;
189 for (i = 0U; i < utf->u_len; i++) {
190 c = (uint8_t)utf->u_name[i];
191
192 /* Complete a multi-byte UTF-8 character */
193 if (utf_cnt) {
194 utf_char = (utf_char << 6) | (c & 0x3fU);
195 if (--utf_cnt)
196 continue;
197 } else {
198 /* Check for a multi-byte UTF-8 character */
199 if (c & 0x80U) {
200 /* Start a multi-byte UTF-8 character */
201 if ((c & 0xe0U) == 0xc0U) {
202 utf_char = c & 0x1fU;
203 utf_cnt = 1;
204 } else if ((c & 0xf0U) == 0xe0U) {
205 utf_char = c & 0x0fU;
206 utf_cnt = 2;
207 } else if ((c & 0xf8U) == 0xf0U) {
208 utf_char = c & 0x07U;
209 utf_cnt = 3;
210 } else if ((c & 0xfcU) == 0xf8U) {
211 utf_char = c & 0x03U;
212 utf_cnt = 4;
213 } else if ((c & 0xfeU) == 0xfcU) {
214 utf_char = c & 0x01U;
215 utf_cnt = 5;
216 } else {
217 goto error_out;
218 }
219 continue;
220 } else {
221 /* Single byte UTF-8 character (most common) */
222 utf_char = c;
223 }
224 }
225
226 /* Choose no compression if necessary */
227 if (utf_char > max_val) {
228 if (max_val == 0xffU) {
229 max_val = 0xffffU;
230 ocu[0] = (uint8_t)0x10U;
231 goto try_again;
232 }
233 goto error_out;
234 }
235
236 if (max_val == 0xffffU)
237 ocu[++u_len] = (uint8_t)(utf_char >> 8);
238 ocu[++u_len] = (uint8_t)(utf_char & 0xffU);
239 }
240
241 if (utf_cnt) {
242 error_out:
243 ocu[++u_len] = '?';
244 printk(KERN_DEBUG "udf: bad UTF-8 character\n");
245 }
246
247 ocu[length - 1] = (uint8_t)u_len + 1;
248
249 return u_len + 1;
250 }
251
udf_CS0toNLS(struct nls_table * nls,struct ustr * utf_o,const struct ustr * ocu_i)252 static int udf_CS0toNLS(struct nls_table *nls, struct ustr *utf_o,
253 const struct ustr *ocu_i)
254 {
255 const uint8_t *ocu;
256 uint8_t cmp_id, ocu_len;
257 int i;
258
259
260 ocu_len = ocu_i->u_len;
261 if (ocu_len == 0) {
262 memset(utf_o, 0, sizeof(struct ustr));
263 return 0;
264 }
265
266 cmp_id = ocu_i->u_cmpID;
267 if (cmp_id != 8 && cmp_id != 16) {
268 memset(utf_o, 0, sizeof(struct ustr));
269 printk(KERN_ERR "udf: unknown compression code (%d) stri=%s\n",
270 cmp_id, ocu_i->u_name);
271 return 0;
272 }
273
274 ocu = ocu_i->u_name;
275 utf_o->u_len = 0;
276 for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) {
277 /* Expand OSTA compressed Unicode to Unicode */
278 uint32_t c = ocu[i++];
279 if (cmp_id == 16)
280 c = (c << 8) | ocu[i++];
281
282 utf_o->u_len += nls->uni2char(c, &utf_o->u_name[utf_o->u_len],
283 UDF_NAME_LEN - utf_o->u_len);
284 }
285 utf_o->u_cmpID = 8;
286
287 return utf_o->u_len;
288 }
289
udf_NLStoCS0(struct nls_table * nls,dstring * ocu,struct ustr * uni,int length)290 static int udf_NLStoCS0(struct nls_table *nls, dstring *ocu, struct ustr *uni,
291 int length)
292 {
293 unsigned len, i, max_val;
294 uint16_t uni_char;
295 int u_len;
296
297 memset(ocu, 0, sizeof(dstring) * length);
298 ocu[0] = 8;
299 max_val = 0xffU;
300
301 try_again:
302 u_len = 0U;
303 for (i = 0U; i < uni->u_len; i++) {
304 len = nls->char2uni(&uni->u_name[i], uni->u_len - i, &uni_char);
305 if (len <= 0)
306 continue;
307
308 if (uni_char > max_val) {
309 max_val = 0xffffU;
310 ocu[0] = (uint8_t)0x10U;
311 goto try_again;
312 }
313
314 if (max_val == 0xffffU)
315 ocu[++u_len] = (uint8_t)(uni_char >> 8);
316 ocu[++u_len] = (uint8_t)(uni_char & 0xffU);
317 i += len - 1;
318 }
319
320 ocu[length - 1] = (uint8_t)u_len + 1;
321 return u_len + 1;
322 }
323
udf_get_filename(struct super_block * sb,uint8_t * sname,uint8_t * dname,int flen)324 int udf_get_filename(struct super_block *sb, uint8_t *sname, uint8_t *dname,
325 int flen)
326 {
327 struct ustr filename, unifilename;
328 int len;
329
330 if (udf_build_ustr_exact(&unifilename, sname, flen))
331 return 0;
332
333 if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
334 if (!udf_CS0toUTF8(&filename, &unifilename)) {
335 udf_debug("Failed in udf_get_filename: sname = %s\n",
336 sname);
337 return 0;
338 }
339 } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
340 if (!udf_CS0toNLS(UDF_SB(sb)->s_nls_map, &filename,
341 &unifilename)) {
342 udf_debug("Failed in udf_get_filename: sname = %s\n",
343 sname);
344 return 0;
345 }
346 } else
347 return 0;
348
349 len = udf_translate_to_linux(dname, filename.u_name, filename.u_len,
350 unifilename.u_name, unifilename.u_len);
351 if (len)
352 return len;
353
354 return 0;
355 }
356
udf_put_filename(struct super_block * sb,const uint8_t * sname,uint8_t * dname,int flen)357 int udf_put_filename(struct super_block *sb, const uint8_t *sname,
358 uint8_t *dname, int flen)
359 {
360 struct ustr unifilename;
361 int namelen;
362
363 if (!udf_char_to_ustr(&unifilename, sname, flen))
364 return 0;
365
366 if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
367 namelen = udf_UTF8toCS0(dname, &unifilename, UDF_NAME_LEN);
368 if (!namelen)
369 return 0;
370 } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
371 namelen = udf_NLStoCS0(UDF_SB(sb)->s_nls_map, dname,
372 &unifilename, UDF_NAME_LEN);
373 if (!namelen)
374 return 0;
375 } else
376 return 0;
377
378 return namelen;
379 }
380
381 #define ILLEGAL_CHAR_MARK '_'
382 #define EXT_MARK '.'
383 #define CRC_MARK '#'
384 #define EXT_SIZE 5
385
udf_translate_to_linux(uint8_t * newName,uint8_t * udfName,int udfLen,uint8_t * fidName,int fidNameLen)386 static int udf_translate_to_linux(uint8_t *newName, uint8_t *udfName,
387 int udfLen, uint8_t *fidName,
388 int fidNameLen)
389 {
390 int index, newIndex = 0, needsCRC = 0;
391 int extIndex = 0, newExtIndex = 0, hasExt = 0;
392 unsigned short valueCRC;
393 uint8_t curr;
394 const uint8_t hexChar[] = "0123456789ABCDEF";
395
396 if (udfName[0] == '.' &&
397 (udfLen == 1 || (udfLen == 2 && udfName[1] == '.'))) {
398 needsCRC = 1;
399 newIndex = udfLen;
400 memcpy(newName, udfName, udfLen);
401 } else {
402 for (index = 0; index < udfLen; index++) {
403 curr = udfName[index];
404 if (curr == '/' || curr == 0) {
405 needsCRC = 1;
406 curr = ILLEGAL_CHAR_MARK;
407 while (index + 1 < udfLen &&
408 (udfName[index + 1] == '/' ||
409 udfName[index + 1] == 0))
410 index++;
411 }
412 if (curr == EXT_MARK &&
413 (udfLen - index - 1) <= EXT_SIZE) {
414 if (udfLen == index + 1)
415 hasExt = 0;
416 else {
417 hasExt = 1;
418 extIndex = index;
419 newExtIndex = newIndex;
420 }
421 }
422 if (newIndex < 256)
423 newName[newIndex++] = curr;
424 else
425 needsCRC = 1;
426 }
427 }
428 if (needsCRC) {
429 uint8_t ext[EXT_SIZE];
430 int localExtIndex = 0;
431
432 if (hasExt) {
433 int maxFilenameLen;
434 for (index = 0;
435 index < EXT_SIZE && extIndex + index + 1 < udfLen;
436 index++) {
437 curr = udfName[extIndex + index + 1];
438
439 if (curr == '/' || curr == 0) {
440 needsCRC = 1;
441 curr = ILLEGAL_CHAR_MARK;
442 while (extIndex + index + 2 < udfLen &&
443 (index + 1 < EXT_SIZE &&
444 (udfName[extIndex + index + 2] == '/' ||
445 udfName[extIndex + index + 2] == 0)))
446 index++;
447 }
448 ext[localExtIndex++] = curr;
449 }
450 maxFilenameLen = 250 - localExtIndex;
451 if (newIndex > maxFilenameLen)
452 newIndex = maxFilenameLen;
453 else
454 newIndex = newExtIndex;
455 } else if (newIndex > 250)
456 newIndex = 250;
457 newName[newIndex++] = CRC_MARK;
458 valueCRC = crc_itu_t(0, fidName, fidNameLen);
459 newName[newIndex++] = hexChar[(valueCRC & 0xf000) >> 12];
460 newName[newIndex++] = hexChar[(valueCRC & 0x0f00) >> 8];
461 newName[newIndex++] = hexChar[(valueCRC & 0x00f0) >> 4];
462 newName[newIndex++] = hexChar[(valueCRC & 0x000f)];
463
464 if (hasExt) {
465 newName[newIndex++] = EXT_MARK;
466 for (index = 0; index < localExtIndex; index++)
467 newName[newIndex++] = ext[index];
468 }
469 }
470
471 return newIndex;
472 }
473