Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / fs / udf / unicode.c
blobf897e55f2cd07f57de7b01f2db92063ce7faa7a8
1 /*
2 * unicode.c
4 * PURPOSE
5 * Routines for converting between UTF-8 and OSTA Compressed Unicode.
6 * Also handles filename mangling
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
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.
21 #include "udfdecl.h"
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 #include <linux/slab.h>
29 #include "udf_sb.h"
31 static int udf_uni2char_utf8(wchar_t uni,
32 unsigned char *out,
33 int boundlen)
35 int u_len = 0;
37 if (boundlen <= 0)
38 return -ENAMETOOLONG;
40 if (uni < 0x80) {
41 out[u_len++] = (unsigned char)uni;
42 } else if (uni < 0x800) {
43 if (boundlen < 2)
44 return -ENAMETOOLONG;
45 out[u_len++] = (unsigned char)(0xc0 | (uni >> 6));
46 out[u_len++] = (unsigned char)(0x80 | (uni & 0x3f));
47 } else {
48 if (boundlen < 3)
49 return -ENAMETOOLONG;
50 out[u_len++] = (unsigned char)(0xe0 | (uni >> 12));
51 out[u_len++] = (unsigned char)(0x80 | ((uni >> 6) & 0x3f));
52 out[u_len++] = (unsigned char)(0x80 | (uni & 0x3f));
54 return u_len;
57 static int udf_char2uni_utf8(const unsigned char *in,
58 int boundlen,
59 wchar_t *uni)
61 unsigned int utf_char;
62 unsigned char c;
63 int utf_cnt, u_len;
65 utf_char = 0;
66 utf_cnt = 0;
67 for (u_len = 0; u_len < boundlen;) {
68 c = in[u_len++];
70 /* Complete a multi-byte UTF-8 character */
71 if (utf_cnt) {
72 utf_char = (utf_char << 6) | (c & 0x3f);
73 if (--utf_cnt)
74 continue;
75 } else {
76 /* Check for a multi-byte UTF-8 character */
77 if (c & 0x80) {
78 /* Start a multi-byte UTF-8 character */
79 if ((c & 0xe0) == 0xc0) {
80 utf_char = c & 0x1f;
81 utf_cnt = 1;
82 } else if ((c & 0xf0) == 0xe0) {
83 utf_char = c & 0x0f;
84 utf_cnt = 2;
85 } else if ((c & 0xf8) == 0xf0) {
86 utf_char = c & 0x07;
87 utf_cnt = 3;
88 } else if ((c & 0xfc) == 0xf8) {
89 utf_char = c & 0x03;
90 utf_cnt = 4;
91 } else if ((c & 0xfe) == 0xfc) {
92 utf_char = c & 0x01;
93 utf_cnt = 5;
94 } else {
95 utf_cnt = -1;
96 break;
98 continue;
99 } else {
100 /* Single byte UTF-8 character (most common) */
101 utf_char = c;
104 *uni = utf_char;
105 break;
107 if (utf_cnt) {
108 *uni = '?';
109 return -EINVAL;
111 return u_len;
114 #define ILLEGAL_CHAR_MARK '_'
115 #define EXT_MARK '.'
116 #define CRC_MARK '#'
117 #define EXT_SIZE 5
118 /* Number of chars we need to store generated CRC to make filename unique */
119 #define CRC_LEN 5
121 static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len,
122 int *str_o_idx,
123 const uint8_t *str_i, int str_i_max_len,
124 int *str_i_idx,
125 int u_ch, int *needsCRC,
126 int (*conv_f)(wchar_t, unsigned char *, int),
127 int translate)
129 uint32_t c;
130 int illChar = 0;
131 int len, gotch = 0;
133 for (; (!gotch) && (*str_i_idx < str_i_max_len); *str_i_idx += u_ch) {
134 if (*str_o_idx >= str_o_max_len) {
135 *needsCRC = 1;
136 return gotch;
139 /* Expand OSTA compressed Unicode to Unicode */
140 c = str_i[*str_i_idx];
141 if (u_ch > 1)
142 c = (c << 8) | str_i[*str_i_idx + 1];
144 if (translate && (c == '/' || c == 0))
145 illChar = 1;
146 else if (illChar)
147 break;
148 else
149 gotch = 1;
151 if (illChar) {
152 *needsCRC = 1;
153 c = ILLEGAL_CHAR_MARK;
154 gotch = 1;
156 if (gotch) {
157 len = conv_f(c, &str_o[*str_o_idx], str_o_max_len - *str_o_idx);
158 /* Valid character? */
159 if (len >= 0)
160 *str_o_idx += len;
161 else if (len == -ENAMETOOLONG) {
162 *needsCRC = 1;
163 gotch = 0;
164 } else {
165 str_o[(*str_o_idx)++] = '?';
166 *needsCRC = 1;
169 return gotch;
172 static int udf_name_from_CS0(uint8_t *str_o, int str_max_len,
173 const uint8_t *ocu, int ocu_len,
174 int (*conv_f)(wchar_t, unsigned char *, int),
175 int translate)
177 uint32_t c;
178 uint8_t cmp_id;
179 int idx, len;
180 int u_ch;
181 int needsCRC = 0;
182 int ext_i_len, ext_max_len;
183 int str_o_len = 0; /* Length of resulting output */
184 int ext_o_len = 0; /* Extension output length */
185 int ext_crc_len = 0; /* Extension output length if used with CRC */
186 int i_ext = -1; /* Extension position in input buffer */
187 int o_crc = 0; /* Rightmost possible output pos for CRC+ext */
188 unsigned short valueCRC;
189 uint8_t ext[EXT_SIZE * NLS_MAX_CHARSET_SIZE + 1];
190 uint8_t crc[CRC_LEN];
192 if (str_max_len <= 0)
193 return 0;
195 if (ocu_len == 0) {
196 memset(str_o, 0, str_max_len);
197 return 0;
200 cmp_id = ocu[0];
201 if (cmp_id != 8 && cmp_id != 16) {
202 memset(str_o, 0, str_max_len);
203 pr_err("unknown compression code (%u)\n", cmp_id);
204 return -EINVAL;
206 u_ch = cmp_id >> 3;
208 ocu++;
209 ocu_len--;
211 if (ocu_len % u_ch) {
212 pr_err("incorrect filename length (%d)\n", ocu_len + 1);
213 return -EINVAL;
216 if (translate) {
217 /* Look for extension */
218 for (idx = ocu_len - u_ch, ext_i_len = 0;
219 (idx >= 0) && (ext_i_len < EXT_SIZE);
220 idx -= u_ch, ext_i_len++) {
221 c = ocu[idx];
222 if (u_ch > 1)
223 c = (c << 8) | ocu[idx + 1];
225 if (c == EXT_MARK) {
226 if (ext_i_len)
227 i_ext = idx;
228 break;
231 if (i_ext >= 0) {
232 /* Convert extension */
233 ext_max_len = min_t(int, sizeof(ext), str_max_len);
234 ext[ext_o_len++] = EXT_MARK;
235 idx = i_ext + u_ch;
236 while (udf_name_conv_char(ext, ext_max_len, &ext_o_len,
237 ocu, ocu_len, &idx,
238 u_ch, &needsCRC,
239 conv_f, translate)) {
240 if ((ext_o_len + CRC_LEN) < str_max_len)
241 ext_crc_len = ext_o_len;
246 idx = 0;
247 while (1) {
248 if (translate && (idx == i_ext)) {
249 if (str_o_len > (str_max_len - ext_o_len))
250 needsCRC = 1;
251 break;
254 if (!udf_name_conv_char(str_o, str_max_len, &str_o_len,
255 ocu, ocu_len, &idx,
256 u_ch, &needsCRC, conv_f, translate))
257 break;
259 if (translate &&
260 (str_o_len <= (str_max_len - ext_o_len - CRC_LEN)))
261 o_crc = str_o_len;
264 if (translate) {
265 if (str_o_len <= 2 && str_o[0] == '.' &&
266 (str_o_len == 1 || str_o[1] == '.'))
267 needsCRC = 1;
268 if (needsCRC) {
269 str_o_len = o_crc;
270 valueCRC = crc_itu_t(0, ocu, ocu_len);
271 crc[0] = CRC_MARK;
272 crc[1] = hex_asc_upper_hi(valueCRC >> 8);
273 crc[2] = hex_asc_upper_lo(valueCRC >> 8);
274 crc[3] = hex_asc_upper_hi(valueCRC);
275 crc[4] = hex_asc_upper_lo(valueCRC);
276 len = min_t(int, CRC_LEN, str_max_len - str_o_len);
277 memcpy(&str_o[str_o_len], crc, len);
278 str_o_len += len;
279 ext_o_len = ext_crc_len;
281 if (ext_o_len > 0) {
282 memcpy(&str_o[str_o_len], ext, ext_o_len);
283 str_o_len += ext_o_len;
287 return str_o_len;
290 static int udf_name_to_CS0(uint8_t *ocu, int ocu_max_len,
291 const uint8_t *str_i, int str_len,
292 int (*conv_f)(const unsigned char *, int, wchar_t *))
294 int i, len;
295 unsigned int max_val;
296 wchar_t uni_char;
297 int u_len, u_ch;
299 if (ocu_max_len <= 0)
300 return 0;
302 memset(ocu, 0, ocu_max_len);
303 ocu[0] = 8;
304 max_val = 0xff;
305 u_ch = 1;
307 try_again:
308 u_len = 1;
309 for (i = 0; i < str_len; i++) {
310 /* Name didn't fit? */
311 if (u_len + u_ch > ocu_max_len)
312 return 0;
313 len = conv_f(&str_i[i], str_len - i, &uni_char);
314 if (!len)
315 continue;
316 /* Invalid character, deal with it */
317 if (len < 0) {
318 len = 1;
319 uni_char = '?';
322 if (uni_char > max_val) {
323 max_val = 0xffff;
324 ocu[0] = 0x10;
325 u_ch = 2;
326 goto try_again;
329 if (max_val == 0xffff)
330 ocu[u_len++] = (uint8_t)(uni_char >> 8);
331 ocu[u_len++] = (uint8_t)(uni_char & 0xff);
332 i += len - 1;
335 return u_len;
338 int udf_dstrCS0toUTF8(uint8_t *utf_o, int o_len,
339 const uint8_t *ocu_i, int i_len)
341 int s_len = 0;
343 if (i_len > 0) {
344 s_len = ocu_i[i_len - 1];
345 if (s_len >= i_len) {
346 pr_err("incorrect dstring lengths (%d/%d)\n",
347 s_len, i_len);
348 return -EINVAL;
352 return udf_name_from_CS0(utf_o, o_len, ocu_i, s_len,
353 udf_uni2char_utf8, 0);
356 int udf_get_filename(struct super_block *sb, const uint8_t *sname, int slen,
357 uint8_t *dname, int dlen)
359 int (*conv_f)(wchar_t, unsigned char *, int);
360 int ret;
362 if (!slen)
363 return -EIO;
365 if (dlen <= 0)
366 return 0;
368 if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
369 conv_f = udf_uni2char_utf8;
370 } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
371 conv_f = UDF_SB(sb)->s_nls_map->uni2char;
372 } else
373 BUG();
375 ret = udf_name_from_CS0(dname, dlen, sname, slen, conv_f, 1);
376 /* Zero length filename isn't valid... */
377 if (ret == 0)
378 ret = -EINVAL;
379 return ret;
382 int udf_put_filename(struct super_block *sb, const uint8_t *sname, int slen,
383 uint8_t *dname, int dlen)
385 int (*conv_f)(const unsigned char *, int, wchar_t *);
387 if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
388 conv_f = udf_char2uni_utf8;
389 } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
390 conv_f = UDF_SB(sb)->s_nls_map->char2uni;
391 } else
392 BUG();
394 return udf_name_to_CS0(dname, dlen, sname, slen, conv_f);