xref: /freebsd/sys/libkern/iconv.c (revision 39beb93c3f8bdbf72a61fda42300b5ebed7390c8)
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/sx.h>
43 #include <sys/syslog.h>
44 
45 #include "iconv_converter_if.h"
46 
47 SYSCTL_DECL(_kern_iconv);
48 
49 SYSCTL_NODE(_kern, OID_AUTO, iconv, CTLFLAG_RW, NULL, "kernel iconv interface");
50 
51 MALLOC_DEFINE(M_ICONV, "iconv", "ICONV structures");
52 MALLOC_DEFINE(M_ICONVDATA, "iconv_data", "ICONV data");
53 
54 MODULE_VERSION(libiconv, 2);
55 
56 static struct sx iconv_lock;
57 
58 #ifdef notnow
59 /*
60  * iconv converter instance
61  */
62 struct iconv_converter {
63 	KOBJ_FIELDS;
64 	void *			c_data;
65 };
66 #endif
67 
68 struct sysctl_oid *iconv_oid_hook = &sysctl___kern_iconv;
69 
70 /*
71  * List of loaded converters
72  */
73 static TAILQ_HEAD(iconv_converter_list, iconv_converter_class)
74     iconv_converters = TAILQ_HEAD_INITIALIZER(iconv_converters);
75 
76 /*
77  * List of supported/loaded charsets pairs
78  */
79 static TAILQ_HEAD(, iconv_cspair)
80     iconv_cslist = TAILQ_HEAD_INITIALIZER(iconv_cslist);
81 static int iconv_csid = 1;
82 
83 static char iconv_unicode_string[] = "unicode";	/* save eight bytes when possible */
84 
85 static void iconv_unregister_cspair(struct iconv_cspair *csp);
86 
87 static int
88 iconv_mod_unload(void)
89 {
90 	struct iconv_cspair *csp;
91 
92 	sx_xlock(&iconv_lock);
93 	while ((csp = TAILQ_FIRST(&iconv_cslist)) != NULL) {
94 		if (csp->cp_refcount)
95 			return EBUSY;
96 	}
97 
98 	while ((csp = TAILQ_FIRST(&iconv_cslist)) != NULL)
99 		iconv_unregister_cspair(csp);
100 	sx_xunlock(&iconv_lock);
101 	sx_destroy(&iconv_lock);
102 	return 0;
103 }
104 
105 static int
106 iconv_mod_handler(module_t mod, int type, void *data)
107 {
108 	int error;
109 
110 	switch (type) {
111 	    case MOD_LOAD:
112 		error = 0;
113 		sx_init(&iconv_lock, "iconv");
114 		break;
115 	    case MOD_UNLOAD:
116 		error = iconv_mod_unload();
117 		break;
118 	    default:
119 		error = EINVAL;
120 	}
121 	return error;
122 }
123 
124 static moduledata_t iconv_mod = {
125 	"iconv", iconv_mod_handler, NULL
126 };
127 
128 DECLARE_MODULE(iconv, iconv_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND);
129 
130 static int
131 iconv_register_converter(struct iconv_converter_class *dcp)
132 {
133 	kobj_class_compile((struct kobj_class*)dcp);
134 	dcp->refs++;
135 	TAILQ_INSERT_TAIL(&iconv_converters, dcp, cc_link);
136 	return 0;
137 }
138 
139 static int
140 iconv_unregister_converter(struct iconv_converter_class *dcp)
141 {
142 	if (dcp->refs > 1) {
143 		ICDEBUG("converter have %d referenses left\n", dcp->refs);
144 		return EBUSY;
145 	}
146 	TAILQ_REMOVE(&iconv_converters, dcp, cc_link);
147 	kobj_class_free((struct kobj_class*)dcp);
148 	return 0;
149 }
150 
151 static int
152 iconv_lookupconv(const char *name, struct iconv_converter_class **dcpp)
153 {
154 	struct iconv_converter_class *dcp;
155 
156 	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
157 		if (name == NULL)
158 			continue;
159 		if (strcmp(name, ICONV_CONVERTER_NAME(dcp)) == 0) {
160 			if (dcpp)
161 				*dcpp = dcp;
162 			return 0;
163 		}
164 	}
165 	return ENOENT;
166 }
167 
168 static int
169 iconv_lookupcs(const char *to, const char *from, struct iconv_cspair **cspp)
170 {
171 	struct iconv_cspair *csp;
172 
173 	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
174 		if (strcmp(csp->cp_to, to) == 0 &&
175 		    strcmp(csp->cp_from, from) == 0) {
176 			if (cspp)
177 				*cspp = csp;
178 			return 0;
179 		}
180 	}
181 	return ENOENT;
182 }
183 
184 static int
185 iconv_register_cspair(const char *to, const char *from,
186 	struct iconv_converter_class *dcp, void *data,
187 	struct iconv_cspair **cspp)
188 {
189 	struct iconv_cspair *csp;
190 	char *cp;
191 	int csize, ucsto, ucsfrom;
192 
193 	if (iconv_lookupcs(to, from, NULL) == 0)
194 		return EEXIST;
195 	csize = sizeof(*csp);
196 	ucsto = strcmp(to, iconv_unicode_string) == 0;
197 	if (!ucsto)
198 		csize += strlen(to) + 1;
199 	ucsfrom = strcmp(from, iconv_unicode_string) == 0;
200 	if (!ucsfrom)
201 		csize += strlen(from) + 1;
202 	csp = malloc(csize, M_ICONV, M_WAITOK);
203 	bzero(csp, csize);
204 	csp->cp_id = iconv_csid++;
205 	csp->cp_dcp = dcp;
206 	cp = (char*)(csp + 1);
207 	if (!ucsto) {
208 		strcpy(cp, to);
209 		csp->cp_to = cp;
210 		cp += strlen(cp) + 1;
211 	} else
212 		csp->cp_to = iconv_unicode_string;
213 	if (!ucsfrom) {
214 		strcpy(cp, from);
215 		csp->cp_from = cp;
216 	} else
217 		csp->cp_from = iconv_unicode_string;
218 	csp->cp_data = data;
219 
220 	TAILQ_INSERT_TAIL(&iconv_cslist, csp, cp_link);
221 	*cspp = csp;
222 	return 0;
223 }
224 
225 static void
226 iconv_unregister_cspair(struct iconv_cspair *csp)
227 {
228 	TAILQ_REMOVE(&iconv_cslist, csp, cp_link);
229 	if (csp->cp_data)
230 		free(csp->cp_data, M_ICONVDATA);
231 	free(csp, M_ICONV);
232 }
233 
234 /*
235  * Lookup and create an instance of converter.
236  * Currently this layer didn't have associated 'instance' structure
237  * to avoid unnesessary memory allocation.
238  */
239 int
240 iconv_open(const char *to, const char *from, void **handle)
241 {
242 	struct iconv_cspair *csp, *cspfrom, *cspto;
243 	struct iconv_converter_class *dcp;
244 	const char *cnvname;
245 	int error;
246 
247 	/*
248 	 * First, lookup fully qualified cspairs
249 	 */
250 	error = iconv_lookupcs(to, from, &csp);
251 	if (error == 0)
252 		return ICONV_CONVERTER_OPEN(csp->cp_dcp, csp, NULL, handle);
253 
254 	/*
255 	 * Well, nothing found. Now try to construct a composite conversion
256 	 * ToDo: add a 'capability' field to converter
257 	 */
258 	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
259 		cnvname = ICONV_CONVERTER_NAME(dcp);
260 		if (cnvname == NULL)
261 			continue;
262 		error = iconv_lookupcs(cnvname, from, &cspfrom);
263 		if (error)
264 			continue;
265 		error = iconv_lookupcs(to, cnvname, &cspto);
266 		if (error)
267 			continue;
268 		/*
269 		 * Fine, we're found a pair which can be combined together
270 		 */
271 		return ICONV_CONVERTER_OPEN(dcp, cspto, cspfrom, handle);
272 	}
273 	return ENOENT;
274 }
275 
276 int
277 iconv_close(void *handle)
278 {
279 	return ICONV_CONVERTER_CLOSE(handle);
280 }
281 
282 int
283 iconv_conv(void *handle, const char **inbuf,
284 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
285 {
286 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 0, 0);
287 }
288 
289 int
290 iconv_conv_case(void *handle, const char **inbuf,
291 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft, int casetype)
292 {
293 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 0, casetype);
294 }
295 
296 int
297 iconv_convchr(void *handle, const char **inbuf,
298 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
299 {
300 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 1, 0);
301 }
302 
303 int
304 iconv_convchr_case(void *handle, const char **inbuf,
305 	size_t *inbytesleft, char **outbuf, size_t *outbytesleft, int casetype)
306 {
307 	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 1, casetype);
308 }
309 
310 /*
311  * Give a list of loaded converters. Each name terminated with 0.
312  * An empty string terminates the list.
313  */
314 static int
315 iconv_sysctl_drvlist(SYSCTL_HANDLER_ARGS)
316 {
317 	struct iconv_converter_class *dcp;
318 	const char *name;
319 	char spc;
320 	int error;
321 
322 	error = 0;
323 	sx_slock(&iconv_lock);
324 	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
325 		name = ICONV_CONVERTER_NAME(dcp);
326 		if (name == NULL)
327 			continue;
328 		error = SYSCTL_OUT(req, name, strlen(name) + 1);
329 		if (error)
330 			break;
331 	}
332 	sx_sunlock(&iconv_lock);
333 	if (error)
334 		return error;
335 	spc = 0;
336 	error = SYSCTL_OUT(req, &spc, sizeof(spc));
337 	return error;
338 }
339 
340 SYSCTL_PROC(_kern_iconv, OID_AUTO, drvlist, CTLFLAG_RD | CTLTYPE_OPAQUE,
341 	    NULL, 0, iconv_sysctl_drvlist, "S,xlat", "registered converters");
342 
343 /*
344  * List all available charset pairs.
345  */
346 static int
347 iconv_sysctl_cslist(SYSCTL_HANDLER_ARGS)
348 {
349 	struct iconv_cspair *csp;
350 	struct iconv_cspair_info csi;
351 	int error;
352 
353 	error = 0;
354 	bzero(&csi, sizeof(csi));
355 	csi.cs_version = ICONV_CSPAIR_INFO_VER;
356 	sx_slock(&iconv_lock);
357 	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
358 		csi.cs_id = csp->cp_id;
359 		csi.cs_refcount = csp->cp_refcount;
360 		csi.cs_base = csp->cp_base ? csp->cp_base->cp_id : 0;
361 		strcpy(csi.cs_to, csp->cp_to);
362 		strcpy(csi.cs_from, csp->cp_from);
363 		error = SYSCTL_OUT(req, &csi, sizeof(csi));
364 		if (error)
365 			break;
366 	}
367 	sx_sunlock(&iconv_lock);
368 	return error;
369 }
370 
371 SYSCTL_PROC(_kern_iconv, OID_AUTO, cslist, CTLFLAG_RD | CTLTYPE_OPAQUE,
372 	    NULL, 0, iconv_sysctl_cslist, "S,xlat", "registered charset pairs");
373 
374 /*
375  * Add new charset pair
376  */
377 static int
378 iconv_sysctl_add(SYSCTL_HANDLER_ARGS)
379 {
380 	struct iconv_converter_class *dcp;
381 	struct iconv_cspair *csp;
382 	struct iconv_add_in din;
383 	struct iconv_add_out dout;
384 	int error;
385 
386 	error = SYSCTL_IN(req, &din, sizeof(din));
387 	if (error)
388 		return error;
389 	if (din.ia_version != ICONV_ADD_VER)
390 		return EINVAL;
391 	if (din.ia_datalen > ICONV_CSMAXDATALEN)
392 		return EINVAL;
393 	if (strlen(din.ia_from) >= ICONV_CSNMAXLEN)
394 		return EINVAL;
395 	if (strlen(din.ia_to) >= ICONV_CSNMAXLEN)
396 		return EINVAL;
397 	if (strlen(din.ia_converter) >= ICONV_CNVNMAXLEN)
398 		return EINVAL;
399 	if (iconv_lookupconv(din.ia_converter, &dcp) != 0)
400 		return EINVAL;
401 	sx_xlock(&iconv_lock);
402 	error = iconv_register_cspair(din.ia_to, din.ia_from, dcp, NULL, &csp);
403 	if (error) {
404 		sx_xunlock(&iconv_lock);
405 		return error;
406 	}
407 	if (din.ia_datalen) {
408 		csp->cp_data = malloc(din.ia_datalen, M_ICONVDATA, M_WAITOK);
409 		error = copyin(din.ia_data, csp->cp_data, din.ia_datalen);
410 		if (error)
411 			goto bad;
412 	}
413 	dout.ia_csid = csp->cp_id;
414 	error = SYSCTL_OUT(req, &dout, sizeof(dout));
415 	if (error)
416 		goto bad;
417 	sx_xunlock(&iconv_lock);
418 	ICDEBUG("%s => %s, %d bytes\n",din.ia_from, din.ia_to, din.ia_datalen);
419 	return 0;
420 bad:
421 	iconv_unregister_cspair(csp);
422 	sx_xunlock(&iconv_lock);
423 	return error;
424 }
425 
426 SYSCTL_PROC(_kern_iconv, OID_AUTO, add, CTLFLAG_RW | CTLTYPE_OPAQUE,
427 	    NULL, 0, iconv_sysctl_add, "S,xlat", "register charset pair");
428 
429 /*
430  * Default stubs for converters
431  */
432 int
433 iconv_converter_initstub(struct iconv_converter_class *dp)
434 {
435 	return 0;
436 }
437 
438 int
439 iconv_converter_donestub(struct iconv_converter_class *dp)
440 {
441 	return 0;
442 }
443 
444 int
445 iconv_converter_handler(module_t mod, int type, void *data)
446 {
447 	struct iconv_converter_class *dcp = data;
448 	int error;
449 
450 	switch (type) {
451 	    case MOD_LOAD:
452 		sx_xlock(&iconv_lock);
453 		error = iconv_register_converter(dcp);
454 		if (error) {
455 			sx_xunlock(&iconv_lock);
456 			break;
457 		}
458 		error = ICONV_CONVERTER_INIT(dcp);
459 		if (error)
460 			iconv_unregister_converter(dcp);
461 		sx_xunlock(&iconv_lock);
462 		break;
463 	    case MOD_UNLOAD:
464 		sx_xlock(&iconv_lock);
465 		ICONV_CONVERTER_DONE(dcp);
466 		error = iconv_unregister_converter(dcp);
467 		sx_xunlock(&iconv_lock);
468 		break;
469 	    default:
470 		error = EINVAL;
471 	}
472 	return error;
473 }
474 
475 /*
476  * Common used functions (don't use with unicode)
477  */
478 char *
479 iconv_convstr(void *handle, char *dst, const char *src)
480 {
481 	char *p = dst;
482 	size_t inlen, outlen;
483 	int error;
484 
485 	if (handle == NULL) {
486 		strcpy(dst, src);
487 		return dst;
488 	}
489 	inlen = outlen = strlen(src);
490 	error = iconv_conv(handle, NULL, NULL, &p, &outlen);
491 	if (error)
492 		return NULL;
493 	error = iconv_conv(handle, &src, &inlen, &p, &outlen);
494 	if (error)
495 		return NULL;
496 	*p = 0;
497 	return dst;
498 }
499 
500 void *
501 iconv_convmem(void *handle, void *dst, const void *src, int size)
502 {
503 	const char *s = src;
504 	char *d = dst;
505 	size_t inlen, outlen;
506 	int error;
507 
508 	if (size == 0)
509 		return dst;
510 	if (handle == NULL) {
511 		memcpy(dst, src, size);
512 		return dst;
513 	}
514 	inlen = outlen = size;
515 	error = iconv_conv(handle, NULL, NULL, &d, &outlen);
516 	if (error)
517 		return NULL;
518 	error = iconv_conv(handle, &s, &inlen, &d, &outlen);
519 	if (error)
520 		return NULL;
521 	return dst;
522 }
523 
524 int
525 iconv_lookupcp(char **cpp, const char *s)
526 {
527 	if (cpp == NULL) {
528 		ICDEBUG("warning a NULL list passed\n", ""); /* XXX ISO variadic								macros cannot
529 								leave out the
530 								variadic args */
531 		return ENOENT;
532 	}
533 	for (; *cpp; cpp++)
534 		if (strcmp(*cpp, s) == 0)
535 			return 0;
536 	return ENOENT;
537 }
538 
539 /*
540  * Return if fsname is in use of not
541  */
542 int
543 iconv_vfs_refcount(const char *fsname)
544 {
545 	struct vfsconf *vfsp;
546 
547 	vfsp = vfs_byname(fsname);
548 	if (vfsp != NULL && vfsp->vfc_refcount > 0)
549 		return (EBUSY);
550 	return (0);
551 }
552