xref: /freebsd/sys/libkern/iconv.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
1 /*
2  * Copyright (c) 2000-2001, Boris Popov
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *    This product includes software developed by Boris Popov.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/iconv.h>
40 #include <sys/malloc.h>
41 #include <sys/mount.h>
42 #include <sys/syslog.h>
43 
44 #include "iconv_converter_if.h"
45 
46 SYSCTL_DECL(_kern_iconv);
47 
48 SYSCTL_NODE(_kern, OID_AUTO, iconv, CTLFLAG_RW, NULL, "kernel iconv interface");
49 
50 MALLOC_DEFINE(M_ICONV, "ICONV", "ICONV structures");
51 MALLOC_DEFINE(M_ICONVDATA, "ICONV data", "ICONV data");
52 
53 MODULE_VERSION(libiconv, 2);
54 
55 #ifdef notnow
56 /*
57  * iconv converter instance
58  */
59 struct iconv_converter {
60 	KOBJ_FIELDS;
61 	void *			c_data;
62 };
63 #endif
64 
65 struct sysctl_oid *iconv_oid_hook = &sysctl___kern_iconv;
66 
67 /*
68  * List of loaded converters
69  */
70 static TAILQ_HEAD(iconv_converter_list, iconv_converter_class)
71     iconv_converters = TAILQ_HEAD_INITIALIZER(iconv_converters);
72 
73 /*
74  * List of supported/loaded charsets pairs
75  */
76 static TAILQ_HEAD(, iconv_cspair)
77     iconv_cslist = TAILQ_HEAD_INITIALIZER(iconv_cslist);
78 static int iconv_csid = 1;
79 
80 static char iconv_unicode_string[] = "unicode";	/* save eight bytes when possible */
81 
82 static void iconv_unregister_cspair(struct iconv_cspair *csp);
83 
84 static int
85 iconv_mod_unload(void)
86 {
87 	struct iconv_cspair *csp;
88 
89 	while ((csp = TAILQ_FIRST(&iconv_cslist)) != NULL) {
90 		if (csp->cp_refcount)
91 			return EBUSY;
92 		iconv_unregister_cspair(csp);
93 	}
94 	return 0;
95 }
96 
97 static int
98 iconv_mod_handler(module_t mod, int type, void *data)
99 {
100 	int error;
101 
102 	switch (type) {
103 	    case MOD_LOAD:
104 		error = 0;
105 		break;
106 	    case MOD_UNLOAD:
107 		error = iconv_mod_unload();
108 		break;
109 	    default:
110 		error = EINVAL;
111 	}
112 	return error;
113 }
114 
115 static moduledata_t iconv_mod = {
116 	"iconv", iconv_mod_handler, NULL
117 };
118 
119 DECLARE_MODULE(iconv, iconv_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND);
120 
121 static int
122 iconv_register_converter(struct iconv_converter_class *dcp)
123 {
124 	kobj_class_compile((struct kobj_class*)dcp);
125 	dcp->refs++;
126 	TAILQ_INSERT_TAIL(&iconv_converters, dcp, cc_link);
127 	return 0;
128 }
129 
130 static int
131 iconv_unregister_converter(struct iconv_converter_class *dcp)
132 {
133 	if (dcp->refs > 1) {
134 		ICDEBUG("converter have %d referenses left\n", dcp->refs);
135 		return EBUSY;
136 	}
137 	TAILQ_REMOVE(&iconv_converters, dcp, cc_link);
138 	kobj_class_free((struct kobj_class*)dcp);
139 	return 0;
140 }
141 
142 static int
143 iconv_lookupconv(const char *name, struct iconv_converter_class **dcpp)
144 {
145 	struct iconv_converter_class *dcp;
146 
147 	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
148 		if (name == NULL)
149 			continue;
150 		if (strcmp(name, ICONV_CONVERTER_NAME(dcp)) == 0) {
151 			if (dcpp)
152 				*dcpp = dcp;
153 			return 0;
154 		}
155 	}
156 	return ENOENT;
157 }
158 
159 static int
160 iconv_lookupcs(const char *to, const char *from, struct iconv_cspair **cspp)
161 {
162 	struct iconv_cspair *csp;
163 
164 	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
165 		if (strcmp(csp->cp_to, to) == 0 &&
166 		    strcmp(csp->cp_from, from) == 0) {
167 			if (cspp)
168 				*cspp = csp;
169 			return 0;
170 		}
171 	}
172 	return ENOENT;
173 }
174 
175 static int
176 iconv_register_cspair(const char *to, const char *from,
177 	struct iconv_converter_class *dcp, void *data,
178 	struct iconv_cspair **cspp)
179 {
180 	struct iconv_cspair *csp;
181 	char *cp;
182 	int csize, ucsto, ucsfrom;
183 
184 	if (iconv_lookupcs(to, from, NULL) == 0)
185 		return EEXIST;
186 	csize = sizeof(*csp);
187 	ucsto = strcmp(to, iconv_unicode_string) == 0;
188 	if (!ucsto)
189 		csize += strlen(to) + 1;
190 	ucsfrom = strcmp(from, iconv_unicode_string) == 0;
191 	if (!ucsfrom)
192 		csize += strlen(from) + 1;
193 	csp = malloc(csize, M_ICONV, M_WAITOK);
194 	bzero(csp, csize);
195 	csp->cp_id = iconv_csid++;
196 	csp->cp_dcp = dcp;
197 	cp = (char*)(csp + 1);
198 	if (!ucsto) {
199 		strcpy(cp, to);
200 		csp->cp_to = cp;
201 		cp += strlen(cp) + 1;
202 	} else
203 		csp->cp_to = iconv_unicode_string;
204 	if (!ucsfrom) {
205 		strcpy(cp, from);
206 		csp->cp_from = cp;
207 	} else
208 		csp->cp_from = iconv_unicode_string;
209 	csp->cp_data = data;
210 
211 	TAILQ_INSERT_TAIL(&iconv_cslist, csp, cp_link);
212 	*cspp = csp;
213 	return 0;
214 }
215 
216 static void
217 iconv_unregister_cspair(struct iconv_cspair *csp)
218 {
219 	TAILQ_REMOVE(&iconv_cslist, csp, cp_link);
220 	if (csp->cp_data)
221 		free(csp->cp_data, M_ICONVDATA);
222 	free(csp, M_ICONV);
223 }
224 
225 /*
226  * Lookup and create an instance of converter.
227  * Currently this layer didn't have associated 'instance' structure
228  * to avoid unnesessary memory allocation.
229  */
230 int
231 iconv_open(const char *to, const char *from, void **handle)
232 {
233 	struct iconv_cspair *csp, *cspfrom, *cspto;
234 	struct iconv_converter_class *dcp;
235 	const char *cnvname;
236 	int error;
237 
238 	/*
239 	 * First, lookup fully qualified cspairs
240 	 */
241 	error = iconv_lookupcs(to, from, &csp);
242 	if (error == 0)
243 		return ICONV_CONVERTER_OPEN(csp->cp_dcp, csp, NULL, handle);
244 
245 	/*
246 	 * Well, nothing found. Now try to construct a composite conversion
247 	 * ToDo: add a 'capability' field to converter
248 	 */
249 	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
250 		cnvname = ICONV_CONVERTER_NAME(dcp);
251 		if (cnvname == NULL)
252 			continue;
253 		error = iconv_lookupcs(cnvname, from, &cspfrom);
254 		if (error)
255 			continue;
256 		error = iconv_lookupcs(to, cnvname, &cspto);
257 		if (error)
258 			continue;
259 		/*
260 		 * Fine, we're found a pair which can be combined together
261 		 */
262 		return ICONV_CONVERTER_OPEN(dcp, cspto, cspfrom, handle);
263 	}
264 	return ENOENT;
265 }
266 
267 int
268 iconv_close(void *handle)
269 {
270 	return ICONV_CONVERTER_CLOSE(handle);
271 }
272 
273 int
274 iconv_conv(void *handle, const char **inbuf,
275 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
276 {
277 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 0, 0);
278 }
279 
280 int
281 iconv_conv_case(void *handle, const char **inbuf,
282 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft, int casetype)
283 {
284 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 0, casetype);
285 }
286 
287 int
288 iconv_convchr(void *handle, const char **inbuf,
289 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
290 {
291 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 1, 0);
292 }
293 
294 int
295 iconv_convchr_case(void *handle, const char **inbuf,
296 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft, int casetype)
297 {
298 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 1, casetype);
299 }
300 
301 /*
302  * Give a list of loaded converters. Each name terminated with 0.
303  * An empty string terminates the list.
304  */
305 static int
306 iconv_sysctl_drvlist(SYSCTL_HANDLER_ARGS)
307 {
308 	struct iconv_converter_class *dcp;
309 	const char *name;
310 	char spc;
311 	int error;
312 
313 	error = 0;
314 
315 	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
316 		name = ICONV_CONVERTER_NAME(dcp);
317 		if (name == NULL)
318 			continue;
319 		error = SYSCTL_OUT(req, name, strlen(name) + 1);
320 		if (error)
321 			break;
322 	}
323 	if (error)
324 		return error;
325 	spc = 0;
326 	error = SYSCTL_OUT(req, &spc, sizeof(spc));
327 	return error;
328 }
329 
330 SYSCTL_PROC(_kern_iconv, OID_AUTO, drvlist, CTLFLAG_RD | CTLTYPE_OPAQUE,
331 	    NULL, 0, iconv_sysctl_drvlist, "S,xlat", "registered converters");
332 
333 /*
334  * List all available charset pairs.
335  */
336 static int
337 iconv_sysctl_cslist(SYSCTL_HANDLER_ARGS)
338 {
339 	struct iconv_cspair *csp;
340 	struct iconv_cspair_info csi;
341 	int error;
342 
343 	error = 0;
344 	bzero(&csi, sizeof(csi));
345 	csi.cs_version = ICONV_CSPAIR_INFO_VER;
346 
347 	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
348 		csi.cs_id = csp->cp_id;
349 		csi.cs_refcount = csp->cp_refcount;
350 		csi.cs_base = csp->cp_base ? csp->cp_base->cp_id : 0;
351 		strcpy(csi.cs_to, csp->cp_to);
352 		strcpy(csi.cs_from, csp->cp_from);
353 		error = SYSCTL_OUT(req, &csi, sizeof(csi));
354 		if (error)
355 			break;
356 	}
357 	return error;
358 }
359 
360 SYSCTL_PROC(_kern_iconv, OID_AUTO, cslist, CTLFLAG_RD | CTLTYPE_OPAQUE,
361 	    NULL, 0, iconv_sysctl_cslist, "S,xlat", "registered charset pairs");
362 
363 /*
364  * Add new charset pair
365  */
366 static int
367 iconv_sysctl_add(SYSCTL_HANDLER_ARGS)
368 {
369 	struct iconv_converter_class *dcp;
370 	struct iconv_cspair *csp;
371 	struct iconv_add_in din;
372 	struct iconv_add_out dout;
373 	int error;
374 
375 	error = SYSCTL_IN(req, &din, sizeof(din));
376 	if (error)
377 		return error;
378 	if (din.ia_version != ICONV_ADD_VER)
379 		return EINVAL;
380 	if (din.ia_datalen > ICONV_CSMAXDATALEN)
381 		return EINVAL;
382 	if (iconv_lookupconv(din.ia_converter, &dcp) != 0)
383 		return EINVAL;
384 	error = iconv_register_cspair(din.ia_to, din.ia_from, dcp, NULL, &csp);
385 	if (error)
386 		return error;
387 	if (din.ia_datalen) {
388 		csp->cp_data = malloc(din.ia_datalen, M_ICONVDATA, M_WAITOK);
389 		error = copyin(din.ia_data, csp->cp_data, din.ia_datalen);
390 		if (error)
391 			goto bad;
392 	}
393 	dout.ia_csid = csp->cp_id;
394 	error = SYSCTL_OUT(req, &dout, sizeof(dout));
395 	if (error)
396 		goto bad;
397 	ICDEBUG("%s => %s, %d bytes\n",din.ia_from, din.ia_to, din.ia_datalen);
398 	return 0;
399 bad:
400 	iconv_unregister_cspair(csp);
401 	return error;
402 }
403 
404 SYSCTL_PROC(_kern_iconv, OID_AUTO, add, CTLFLAG_RW | CTLTYPE_OPAQUE,
405 	    NULL, 0, iconv_sysctl_add, "S,xlat", "register charset pair");
406 
407 /*
408  * Default stubs for converters
409  */
410 int
411 iconv_converter_initstub(struct iconv_converter_class *dp)
412 {
413 	return 0;
414 }
415 
416 int
417 iconv_converter_donestub(struct iconv_converter_class *dp)
418 {
419 	return 0;
420 }
421 
422 int
423 iconv_converter_handler(module_t mod, int type, void *data)
424 {
425 	struct iconv_converter_class *dcp = data;
426 	int error;
427 
428 	switch (type) {
429 	    case MOD_LOAD:
430 		error = iconv_register_converter(dcp);
431 		if (error)
432 			break;
433 		error = ICONV_CONVERTER_INIT(dcp);
434 		if (error)
435 			iconv_unregister_converter(dcp);
436 		break;
437 	    case MOD_UNLOAD:
438 		ICONV_CONVERTER_DONE(dcp);
439 		error = iconv_unregister_converter(dcp);
440 		break;
441 	    default:
442 		error = EINVAL;
443 	}
444 	return error;
445 }
446 
447 /*
448  * Common used functions (don't use with unicode)
449  */
450 char *
451 iconv_convstr(void *handle, char *dst, const char *src)
452 {
453 	char *p = dst;
454 	size_t inlen, outlen;
455 	int error;
456 
457 	if (handle == NULL) {
458 		strcpy(dst, src);
459 		return dst;
460 	}
461 	inlen = strlen(src);
462 	outlen = inlen * 3;
463 	error = iconv_conv(handle, NULL, NULL, &p, &outlen);
464 	if (error)
465 		return NULL;
466 	error = iconv_conv(handle, &src, &inlen, &p, &outlen);
467 	if (error)
468 		return NULL;
469 	*p = 0;
470 	return dst;
471 }
472 
473 void *
474 iconv_convmem(void *handle, void *dst, const void *src, int size)
475 {
476 	const char *s = src;
477 	char *d = dst;
478 	size_t inlen, outlen;
479 	int error;
480 
481 	if (size == 0)
482 		return dst;
483 	if (handle == NULL) {
484 		memcpy(dst, src, size);
485 		return dst;
486 	}
487 	inlen = size;
488 	outlen = inlen * 3;
489 	error = iconv_conv(handle, NULL, NULL, &d, &outlen);
490 	if (error)
491 		return NULL;
492 	error = iconv_conv(handle, &s, &inlen, &d, &outlen);
493 	if (error)
494 		return NULL;
495 	return dst;
496 }
497 
498 int
499 iconv_lookupcp(char **cpp, const char *s)
500 {
501 	if (cpp == NULL) {
502 		ICDEBUG("warning a NULL list passed\n", ""); /* XXX ISO variadic								macros cannot
503 								leave out the
504 								variadic args */
505 		return ENOENT;
506 	}
507 	for (; *cpp; cpp++)
508 		if (strcmp(*cpp, s) == 0)
509 			return 0;
510 	return ENOENT;
511 }
512 
513 /*
514  * Return if fsname is in use of not
515  */
516 int
517 iconv_vfs_refcount(const char *fsname)
518 {
519 	struct vfsconf *vfsp;
520 
521 	for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) {
522 		if (!strcmp(vfsp->vfc_name, fsname)) {
523 			if (vfsp->vfc_refcount > 0)
524 				return (EBUSY);
525 			else
526 				return (0);
527 		}
528 	}
529 	return (0);
530 }
531