iconv.c revision 330512 
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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/10/sys/libkern/iconv.c 330512 2018-03-05 16:00:05Z dab $");
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/kernel.h>
33#include <sys/iconv.h>
34#include <sys/malloc.h>
35#include <sys/mount.h>
36#include <sys/sx.h>
37#include <sys/syslog.h>
38
39#include "iconv_converter_if.h"
40
41SYSCTL_DECL(_kern_iconv);
42
43SYSCTL_NODE(_kern, OID_AUTO, iconv, CTLFLAG_RW, NULL, "kernel iconv interface");
44
45MALLOC_DEFINE(M_ICONV, "iconv", "ICONV structures");
46static MALLOC_DEFINE(M_ICONVDATA, "iconv_data", "ICONV data");
47
48MODULE_VERSION(libiconv, 2);
49
50static struct sx iconv_lock;
51
52#ifdef notnow
53/*
54 * iconv converter instance
55 */
56struct iconv_converter {
57	KOBJ_FIELDS;
58	void *			c_data;
59};
60#endif
61
62struct sysctl_oid *iconv_oid_hook = &sysctl___kern_iconv;
63
64/*
65 * List of loaded converters
66 */
67static TAILQ_HEAD(iconv_converter_list, iconv_converter_class)
68    iconv_converters = TAILQ_HEAD_INITIALIZER(iconv_converters);
69
70/*
71 * List of supported/loaded charsets pairs
72 */
73static TAILQ_HEAD(, iconv_cspair)
74    iconv_cslist = TAILQ_HEAD_INITIALIZER(iconv_cslist);
75static int iconv_csid = 1;
76
77static char iconv_unicode_string[] = "unicode";	/* save eight bytes when possible */
78
79static void iconv_unregister_cspair(struct iconv_cspair *csp);
80
81static int
82iconv_mod_unload(void)
83{
84	struct iconv_cspair *csp;
85
86	sx_xlock(&iconv_lock);
87	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
88		if (csp->cp_refcount) {
89			sx_xunlock(&iconv_lock);
90			return EBUSY;
91		}
92	}
93
94	while ((csp = TAILQ_FIRST(&iconv_cslist)) != NULL)
95		iconv_unregister_cspair(csp);
96	sx_xunlock(&iconv_lock);
97	sx_destroy(&iconv_lock);
98	return 0;
99}
100
101static int
102iconv_mod_handler(module_t mod, int type, void *data)
103{
104	int error;
105
106	switch (type) {
107	    case MOD_LOAD:
108		error = 0;
109		sx_init(&iconv_lock, "iconv");
110		break;
111	    case MOD_UNLOAD:
112		error = iconv_mod_unload();
113		break;
114	    default:
115		error = EINVAL;
116	}
117	return error;
118}
119
120static moduledata_t iconv_mod = {
121	"iconv", iconv_mod_handler, NULL
122};
123
124DECLARE_MODULE(iconv, iconv_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND);
125
126static int
127iconv_register_converter(struct iconv_converter_class *dcp)
128{
129	kobj_class_compile((struct kobj_class*)dcp);
130	dcp->refs++;
131	TAILQ_INSERT_TAIL(&iconv_converters, dcp, cc_link);
132	return 0;
133}
134
135static int
136iconv_unregister_converter(struct iconv_converter_class *dcp)
137{
138	dcp->refs--;
139	if (dcp->refs > 1) {
140		ICDEBUG("converter have %d referenses left\n", dcp->refs);
141		return EBUSY;
142	}
143	TAILQ_REMOVE(&iconv_converters, dcp, cc_link);
144	kobj_class_free((struct kobj_class*)dcp);
145	return 0;
146}
147
148static int
149iconv_lookupconv(const char *name, struct iconv_converter_class **dcpp)
150{
151	struct iconv_converter_class *dcp;
152
153	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
154		if (name == NULL)
155			continue;
156		if (strcmp(name, ICONV_CONVERTER_NAME(dcp)) == 0) {
157			if (dcpp)
158				*dcpp = dcp;
159			return 0;
160		}
161	}
162	return ENOENT;
163}
164
165static int
166iconv_lookupcs(const char *to, const char *from, struct iconv_cspair **cspp)
167{
168	struct iconv_cspair *csp;
169
170	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
171		if (strcasecmp(csp->cp_to, to) == 0 &&
172		    strcasecmp(csp->cp_from, from) == 0) {
173			if (cspp)
174				*cspp = csp;
175			return 0;
176		}
177	}
178	return ENOENT;
179}
180
181static int
182iconv_register_cspair(const char *to, const char *from,
183	struct iconv_converter_class *dcp, void *data,
184	struct iconv_cspair **cspp)
185{
186	struct iconv_cspair *csp;
187	char *cp;
188	int csize, ucsto, ucsfrom;
189
190	if (iconv_lookupcs(to, from, NULL) == 0)
191		return EEXIST;
192	csize = sizeof(*csp);
193	ucsto = strcmp(to, iconv_unicode_string) == 0;
194	if (!ucsto)
195		csize += strlen(to) + 1;
196	ucsfrom = strcmp(from, iconv_unicode_string) == 0;
197	if (!ucsfrom)
198		csize += strlen(from) + 1;
199	csp = malloc(csize, M_ICONV, M_WAITOK);
200	bzero(csp, csize);
201	csp->cp_id = iconv_csid++;
202	csp->cp_dcp = dcp;
203	cp = (char*)(csp + 1);
204	if (!ucsto) {
205		strcpy(cp, to);
206		csp->cp_to = cp;
207		cp += strlen(cp) + 1;
208	} else
209		csp->cp_to = iconv_unicode_string;
210	if (!ucsfrom) {
211		strcpy(cp, from);
212		csp->cp_from = cp;
213	} else
214		csp->cp_from = iconv_unicode_string;
215	csp->cp_data = data;
216
217	TAILQ_INSERT_TAIL(&iconv_cslist, csp, cp_link);
218	*cspp = csp;
219	return 0;
220}
221
222static void
223iconv_unregister_cspair(struct iconv_cspair *csp)
224{
225	TAILQ_REMOVE(&iconv_cslist, csp, cp_link);
226	if (csp->cp_data)
227		free(csp->cp_data, M_ICONVDATA);
228	free(csp, M_ICONV);
229}
230
231/*
232 * Lookup and create an instance of converter.
233 * Currently this layer didn't have associated 'instance' structure
234 * to avoid unnesessary memory allocation.
235 */
236int
237iconv_open(const char *to, const char *from, void **handle)
238{
239	struct iconv_cspair *csp, *cspfrom, *cspto;
240	struct iconv_converter_class *dcp;
241	const char *cnvname;
242	int error;
243
244	/*
245	 * First, lookup fully qualified cspairs
246	 */
247	error = iconv_lookupcs(to, from, &csp);
248	if (error == 0)
249		return ICONV_CONVERTER_OPEN(csp->cp_dcp, csp, NULL, handle);
250
251	/*
252	 * Well, nothing found. Now try to construct a composite conversion
253	 * ToDo: add a 'capability' field to converter
254	 */
255	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
256		cnvname = ICONV_CONVERTER_NAME(dcp);
257		if (cnvname == NULL)
258			continue;
259		error = iconv_lookupcs(cnvname, from, &cspfrom);
260		if (error)
261			continue;
262		error = iconv_lookupcs(to, cnvname, &cspto);
263		if (error)
264			continue;
265		/*
266		 * Fine, we're found a pair which can be combined together
267		 */
268		return ICONV_CONVERTER_OPEN(dcp, cspto, cspfrom, handle);
269	}
270	return ENOENT;
271}
272
273int
274iconv_close(void *handle)
275{
276	return ICONV_CONVERTER_CLOSE(handle);
277}
278
279int
280iconv_conv(void *handle, const char **inbuf,
281	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
282{
283	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 0, 0);
284}
285
286int
287iconv_conv_case(void *handle, const char **inbuf,
288	size_t *inbytesleft, char **outbuf, size_t *outbytesleft, int casetype)
289{
290	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 0, casetype);
291}
292
293int
294iconv_convchr(void *handle, const char **inbuf,
295	size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
296{
297	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 1, 0);
298}
299
300int
301iconv_convchr_case(void *handle, const char **inbuf,
302	size_t *inbytesleft, char **outbuf, size_t *outbytesleft, int casetype)
303{
304	return ICONV_CONVERTER_CONV(handle, inbuf, inbytesleft, outbuf, outbytesleft, 1, casetype);
305}
306
307int
308towlower(int c, void *handle)
309{
310	return ICONV_CONVERTER_TOLOWER(handle, c);
311}
312
313int
314towupper(int c, void *handle)
315{
316	return ICONV_CONVERTER_TOUPPER(handle, c);
317}
318
319/*
320 * Give a list of loaded converters. Each name terminated with 0.
321 * An empty string terminates the list.
322 */
323static int
324iconv_sysctl_drvlist(SYSCTL_HANDLER_ARGS)
325{
326	struct iconv_converter_class *dcp;
327	const char *name;
328	char spc;
329	int error;
330
331	error = 0;
332	sx_slock(&iconv_lock);
333	TAILQ_FOREACH(dcp, &iconv_converters, cc_link) {
334		name = ICONV_CONVERTER_NAME(dcp);
335		if (name == NULL)
336			continue;
337		error = SYSCTL_OUT(req, name, strlen(name) + 1);
338		if (error)
339			break;
340	}
341	sx_sunlock(&iconv_lock);
342	if (error)
343		return error;
344	spc = 0;
345	error = SYSCTL_OUT(req, &spc, sizeof(spc));
346	return error;
347}
348
349SYSCTL_PROC(_kern_iconv, OID_AUTO, drvlist, CTLFLAG_RD | CTLTYPE_OPAQUE,
350	    NULL, 0, iconv_sysctl_drvlist, "S,xlat", "registered converters");
351
352/*
353 * List all available charset pairs.
354 */
355static int
356iconv_sysctl_cslist(SYSCTL_HANDLER_ARGS)
357{
358	struct iconv_cspair *csp;
359	struct iconv_cspair_info csi;
360	int error;
361
362	error = 0;
363	bzero(&csi, sizeof(csi));
364	csi.cs_version = ICONV_CSPAIR_INFO_VER;
365	sx_slock(&iconv_lock);
366	TAILQ_FOREACH(csp, &iconv_cslist, cp_link) {
367		csi.cs_id = csp->cp_id;
368		csi.cs_refcount = csp->cp_refcount;
369		csi.cs_base = csp->cp_base ? csp->cp_base->cp_id : 0;
370		strcpy(csi.cs_to, csp->cp_to);
371		strcpy(csi.cs_from, csp->cp_from);
372		error = SYSCTL_OUT(req, &csi, sizeof(csi));
373		if (error)
374			break;
375	}
376	sx_sunlock(&iconv_lock);
377	return error;
378}
379
380SYSCTL_PROC(_kern_iconv, OID_AUTO, cslist, CTLFLAG_RD | CTLTYPE_OPAQUE,
381	    NULL, 0, iconv_sysctl_cslist, "S,xlat", "registered charset pairs");
382
383int
384iconv_add(const char *converter, const char *to, const char *from)
385{
386	struct iconv_converter_class *dcp;
387	struct iconv_cspair *csp;
388
389	if (iconv_lookupconv(converter, &dcp) != 0)
390		return EINVAL;
391
392	return iconv_register_cspair(to, from, dcp, NULL, &csp);
393}
394
395/*
396 * Add new charset pair
397 */
398static int
399iconv_sysctl_add(SYSCTL_HANDLER_ARGS)
400{
401	struct iconv_converter_class *dcp;
402	struct iconv_cspair *csp;
403	struct iconv_add_in din;
404	struct iconv_add_out dout;
405	int error;
406
407	error = SYSCTL_IN(req, &din, sizeof(din));
408	if (error)
409		return error;
410	if (din.ia_version != ICONV_ADD_VER)
411		return EINVAL;
412	if (din.ia_datalen > ICONV_CSMAXDATALEN)
413		return EINVAL;
414	if (strnlen(din.ia_from, sizeof(din.ia_from)) >= ICONV_CSNMAXLEN)
415		return EINVAL;
416	if (strnlen(din.ia_to, sizeof(din.ia_to)) >= ICONV_CSNMAXLEN)
417		return EINVAL;
418	if (strnlen(din.ia_converter, sizeof(din.ia_converter)) >= ICONV_CNVNMAXLEN)
419		return EINVAL;
420	if (iconv_lookupconv(din.ia_converter, &dcp) != 0)
421		return EINVAL;
422	sx_xlock(&iconv_lock);
423	error = iconv_register_cspair(din.ia_to, din.ia_from, dcp, NULL, &csp);
424	if (error) {
425		sx_xunlock(&iconv_lock);
426		return error;
427	}
428	if (din.ia_datalen) {
429		csp->cp_data = malloc(din.ia_datalen, M_ICONVDATA, M_WAITOK);
430		error = copyin(din.ia_data, csp->cp_data, din.ia_datalen);
431		if (error)
432			goto bad;
433	}
434	dout.ia_csid = csp->cp_id;
435	error = SYSCTL_OUT(req, &dout, sizeof(dout));
436	if (error)
437		goto bad;
438	sx_xunlock(&iconv_lock);
439	ICDEBUG("%s => %s, %d bytes\n",din.ia_from, din.ia_to, din.ia_datalen);
440	return 0;
441bad:
442	iconv_unregister_cspair(csp);
443	sx_xunlock(&iconv_lock);
444	return error;
445}
446
447SYSCTL_PROC(_kern_iconv, OID_AUTO, add, CTLFLAG_RW | CTLTYPE_OPAQUE,
448	    NULL, 0, iconv_sysctl_add, "S,xlat", "register charset pair");
449
450/*
451 * Default stubs for converters
452 */
453int
454iconv_converter_initstub(struct iconv_converter_class *dp)
455{
456	return 0;
457}
458
459int
460iconv_converter_donestub(struct iconv_converter_class *dp)
461{
462	return 0;
463}
464
465int
466iconv_converter_tolowerstub(int c, void *handle)
467{
468	return (c);
469}
470
471int
472iconv_converter_handler(module_t mod, int type, void *data)
473{
474	struct iconv_converter_class *dcp = data;
475	int error;
476
477	switch (type) {
478	    case MOD_LOAD:
479		sx_xlock(&iconv_lock);
480		error = iconv_register_converter(dcp);
481		if (error) {
482			sx_xunlock(&iconv_lock);
483			break;
484		}
485		error = ICONV_CONVERTER_INIT(dcp);
486		if (error)
487			iconv_unregister_converter(dcp);
488		sx_xunlock(&iconv_lock);
489		break;
490	    case MOD_UNLOAD:
491		sx_xlock(&iconv_lock);
492		ICONV_CONVERTER_DONE(dcp);
493		error = iconv_unregister_converter(dcp);
494		sx_xunlock(&iconv_lock);
495		break;
496	    default:
497		error = EINVAL;
498	}
499	return error;
500}
501
502/*
503 * Common used functions (don't use with unicode)
504 */
505char *
506iconv_convstr(void *handle, char *dst, const char *src)
507{
508	char *p = dst;
509	size_t inlen, outlen;
510	int error;
511
512	if (handle == NULL) {
513		strcpy(dst, src);
514		return dst;
515	}
516	inlen = outlen = strlen(src);
517	error = iconv_conv(handle, NULL, NULL, &p, &outlen);
518	if (error)
519		return NULL;
520	error = iconv_conv(handle, &src, &inlen, &p, &outlen);
521	if (error)
522		return NULL;
523	*p = 0;
524	return dst;
525}
526
527void *
528iconv_convmem(void *handle, void *dst, const void *src, int size)
529{
530	const char *s = src;
531	char *d = dst;
532	size_t inlen, outlen;
533	int error;
534
535	if (size == 0)
536		return dst;
537	if (handle == NULL) {
538		memcpy(dst, src, size);
539		return dst;
540	}
541	inlen = outlen = size;
542	error = iconv_conv(handle, NULL, NULL, &d, &outlen);
543	if (error)
544		return NULL;
545	error = iconv_conv(handle, &s, &inlen, &d, &outlen);
546	if (error)
547		return NULL;
548	return dst;
549}
550
551int
552iconv_lookupcp(char **cpp, const char *s)
553{
554	if (cpp == NULL) {
555		ICDEBUG("warning a NULL list passed\n", "");
556		return ENOENT;
557	}
558	for (; *cpp; cpp++)
559		if (strcmp(*cpp, s) == 0)
560			return 0;
561	return ENOENT;
562}
563
564/*
565 * Return if fsname is in use of not
566 */
567int
568iconv_vfs_refcount(const char *fsname)
569{
570	struct vfsconf *vfsp;
571
572	vfsp = vfs_byname(fsname);
573	if (vfsp != NULL && vfsp->vfc_refcount > 0)
574		return (EBUSY);
575	return (0);
576}
577