xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/wind/utf8.c (revision afab4e300d3a9fb07dd8c80daf53d0feb3345706)
1 /*	$NetBSD: utf8.c,v 1.3 2023/06/19 21:41:45 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2004, 2006, 2007, 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <config.h>
37 #include "windlocl.h"
38 
39 static int
utf8toutf32(const unsigned char ** pp,uint32_t * out)40 utf8toutf32(const unsigned char **pp, uint32_t *out)
41 {
42     const unsigned char *p = *pp;
43     unsigned c = *p;
44 
45     if (c & 0x80) {
46 	if ((c & 0xE0) == 0xC0) {
47 	    const unsigned c2 = *++p;
48 	    if ((c2 & 0xC0) == 0x80) {
49 		*out =  ((c  & 0x1F) << 6)
50 		    | (c2 & 0x3F);
51 	    } else {
52 		return WIND_ERR_INVALID_UTF8;
53 	    }
54 	} else if ((c & 0xF0) == 0xE0) {
55 	    const unsigned c2 = *++p;
56 	    if ((c2 & 0xC0) == 0x80) {
57 		const unsigned c3 = *++p;
58 		if ((c3 & 0xC0) == 0x80) {
59 		    *out =   ((c  & 0x0F) << 12)
60 			| ((c2 & 0x3F) << 6)
61 			|  (c3 & 0x3F);
62 		} else {
63 		    return WIND_ERR_INVALID_UTF8;
64 		}
65 	    } else {
66 		return WIND_ERR_INVALID_UTF8;
67 	    }
68 	} else if ((c & 0xF8) == 0xF0) {
69 	    const unsigned c2 = *++p;
70 	    if ((c2 & 0xC0) == 0x80) {
71 		const unsigned c3 = *++p;
72 		if ((c3 & 0xC0) == 0x80) {
73 		    const unsigned c4 = *++p;
74 		    if ((c4 & 0xC0) == 0x80) {
75 			*out =   ((c  & 0x07) << 18)
76 			    | ((c2 & 0x3F) << 12)
77 			    | ((c3 & 0x3F) <<  6)
78 			    |  (c4 & 0x3F);
79 		    } else {
80 			return WIND_ERR_INVALID_UTF8;
81 		    }
82 		} else {
83 		    return WIND_ERR_INVALID_UTF8;
84 		}
85 	    } else {
86 		return WIND_ERR_INVALID_UTF8;
87 	    }
88 	} else {
89 	    return WIND_ERR_INVALID_UTF8;
90 	}
91     } else {
92 	*out = c;
93     }
94 
95     *pp = p;
96 
97     return 0;
98 }
99 
100 /**
101  * Convert an UTF-8 string to an UCS4 string.
102  *
103  * @param in an UTF-8 string to convert.
104  * @param out the resulting UCS4 strint, must be at least
105  * wind_utf8ucs4_length() long.  If out is NULL, the function will
106  * calculate the needed space for the out variable (just like
107  * wind_utf8ucs4_length()).
108  * @param out_len before processing out_len should be the length of
109  * the out variable, after processing it will be the length of the out
110  * string.
111  *
112  * @return returns 0 on success, an wind error code otherwise
113  * @ingroup wind
114  */
115 
116 int
wind_utf8ucs4(const char * in,uint32_t * out,size_t * out_len)117 wind_utf8ucs4(const char *in, uint32_t *out, size_t *out_len)
118 {
119     const unsigned char *p;
120     size_t o = 0;
121     int ret;
122 
123     for (p = (const unsigned char *)in; *p != '\0'; ++p) {
124 	uint32_t u;
125 
126 	ret = utf8toutf32(&p, &u);
127 	if (ret)
128 	    return ret;
129 
130 	if (out) {
131 	    if (o >= *out_len)
132 		return WIND_ERR_OVERRUN;
133 	    out[o] = u;
134 	}
135 	o++;
136     }
137     *out_len = o;
138     return 0;
139 }
140 
141 /**
142  * Calculate the length of from converting a UTF-8 string to a UCS4
143  * string.
144  *
145  * @param in an UTF-8 string to convert.
146  * @param out_len the length of the resulting UCS4 string.
147  *
148  * @return returns 0 on success, an wind error code otherwise
149  * @ingroup wind
150  */
151 
152 int
wind_utf8ucs4_length(const char * in,size_t * out_len)153 wind_utf8ucs4_length(const char *in, size_t *out_len)
154 {
155     return wind_utf8ucs4(in, NULL, out_len);
156 }
157 
158 static const char first_char[4] =
159     { 0x00, 0xC0, 0xE0, 0xF0 };
160 
161 /**
162  * Convert an UCS4 string to a UTF-8 string.
163  *
164  * @param in an UCS4 string to convert.
165  * @param in_len the length input array.
166 
167  * @param out the resulting UTF-8 strint, must be at least
168  * wind_ucs4utf8_length() + 1 long (the extra char for the NUL).  If
169  * out is NULL, the function will calculate the needed space for the
170  * out variable (just like wind_ucs4utf8_length()).
171 
172  * @param out_len before processing out_len should be the length of
173  * the out variable, after processing it will be the length of the out
174  * string.
175  *
176  * @return returns 0 on success, an wind error code otherwise
177  * @ingroup wind
178  */
179 
180 int
wind_ucs4utf8(const uint32_t * in,size_t in_len,char * out,size_t * out_len)181 wind_ucs4utf8(const uint32_t *in, size_t in_len, char *out, size_t *out_len)
182 {
183     uint32_t ch;
184     size_t i, len, o;
185 
186     for (o = 0, i = 0; i < in_len; i++) {
187 	ch = in[i];
188 
189 	if (ch < 0x80) {
190 	    len = 1;
191 	} else if (ch < 0x800) {
192 	    len = 2;
193 	} else if (ch < 0x10000) {
194 	    len = 3;
195 	} else if (ch <= 0x10FFFF) {
196 	    len = 4;
197 	} else
198 	    return WIND_ERR_INVALID_UTF32;
199 
200 	o += len;
201 
202 	if (out) {
203 	    if (o >= *out_len)
204 		return WIND_ERR_OVERRUN;
205 
206 	    switch(len) {
207 	    case 4:
208 		out[3] = (ch | 0x80) & 0xbf;
209 		ch = ch >> 6;
210                 /* FALLTHROUGH */
211 	    case 3:
212 		out[2] = (ch | 0x80) & 0xbf;
213 		ch = ch >> 6;
214                 /* FALLTHROUGH */
215 	    case 2:
216 		out[1] = (ch | 0x80) & 0xbf;
217 		ch = ch >> 6;
218                 /* FALLTHROUGH */
219 	    case 1:
220 		out[0] = ch | first_char[len - 1];
221                 /* FALLTHROUGH */
222 	    }
223 	}
224 	out += len;
225     }
226     if (out) {
227 	if (o + 1 >= *out_len)
228 	    return WIND_ERR_OVERRUN;
229 	*out = '\0';
230     }
231     *out_len = o;
232     return 0;
233 }
234 
235 /**
236  * Calculate the length of from converting a UCS4 string to an UTF-8 string.
237  *
238  * @param in an UCS4 string to convert.
239  * @param in_len the length of UCS4 string to convert.
240  * @param out_len the length of the resulting UTF-8 string.
241  *
242  * @return returns 0 on success, an wind error code otherwise
243  * @ingroup wind
244  */
245 
246 int
wind_ucs4utf8_length(const uint32_t * in,size_t in_len,size_t * out_len)247 wind_ucs4utf8_length(const uint32_t *in, size_t in_len, size_t *out_len)
248 {
249     return wind_ucs4utf8(in, in_len, NULL, out_len);
250 }
251 
252 /**
253  * Read in an UCS2 from a buffer.
254  *
255  * @param ptr The input buffer to read from.
256  * @param len the length of the input buffer.
257  * @param flags Flags to control the behavior of the function.
258  * @param out the output UCS2, the array must be at least out/2 long.
259  * @param out_len the output length
260  *
261  * @return returns 0 on success, an wind error code otherwise.
262  * @ingroup wind
263  */
264 
265 int
wind_ucs2read(const void * ptr,size_t len,unsigned int * flags,uint16_t * out,size_t * out_len)266 wind_ucs2read(const void *ptr, size_t len, unsigned int *flags,
267 	      uint16_t *out, size_t *out_len)
268 {
269     const unsigned char *p = ptr;
270     int little = ((*flags) & WIND_RW_LE);
271     size_t olen = *out_len;
272 
273     /** if len is zero, flags are unchanged */
274     if (len == 0) {
275 	*out_len = 0;
276 	return 0;
277     }
278 
279     /** if len is odd, WIND_ERR_LENGTH_NOT_MOD2 is returned */
280     if (len & 1)
281 	return WIND_ERR_LENGTH_NOT_MOD2;
282 
283     /**
284      * If the flags WIND_RW_BOM is set, check for BOM. If not BOM is
285      * found, check is LE/BE flag is already and use that otherwise
286      * fail with WIND_ERR_NO_BOM. When done, clear WIND_RW_BOM and
287      * the LE/BE flag and set the resulting LE/BE flag.
288      */
289     if ((*flags) & WIND_RW_BOM) {
290 	uint16_t bom = (p[0] << 8) + p[1];
291 	if (bom == 0xfffe || bom == 0xfeff) {
292 	    little = (bom == 0xfffe);
293 	    p += 2;
294 	    len -= 2;
295 	} else if (((*flags) & (WIND_RW_LE|WIND_RW_BE)) != 0) {
296 	    /* little already set */
297 	} else
298 	    return WIND_ERR_NO_BOM;
299 	*flags = ((*flags) & ~(WIND_RW_BOM|WIND_RW_LE|WIND_RW_BE));
300 	*flags |= little ? WIND_RW_LE : WIND_RW_BE;
301     }
302 
303     while (len) {
304 	if (olen < 1)
305 	    return WIND_ERR_OVERRUN;
306 	if (little)
307 	    *out = (p[1] << 8) + p[0];
308 	else
309 	    *out = (p[0] << 8) + p[1];
310 	out++; p += 2; len -= 2; olen--;
311     }
312     *out_len -= olen;
313     return 0;
314 }
315 
316 /**
317  * Write an UCS2 string to a buffer.
318  *
319  * @param in The input UCS2 string.
320  * @param in_len the length of the input buffer.
321  * @param flags Flags to control the behavior of the function.
322  * @param ptr The input buffer to write to, the array must be at least
323  * (in + 1) * 2 bytes long.
324  * @param out_len the output length
325  *
326  * @return returns 0 on success, an wind error code otherwise.
327  * @ingroup wind
328  */
329 
330 int
wind_ucs2write(const uint16_t * in,size_t in_len,unsigned int * flags,void * ptr,size_t * out_len)331 wind_ucs2write(const uint16_t *in, size_t in_len, unsigned int *flags,
332 	       void *ptr, size_t *out_len)
333 {
334     unsigned char *p = ptr;
335     size_t len = *out_len;
336 
337     /** If in buffer is not of length be mod 2, WIND_ERR_LENGTH_NOT_MOD2 is returned*/
338     if (len & 1)
339 	return WIND_ERR_LENGTH_NOT_MOD2;
340 
341     /** On zero input length, flags are preserved */
342     if (in_len == 0) {
343 	*out_len = 0;
344 	return 0;
345     }
346     /** If flags have WIND_RW_BOM set, the byte order mark is written
347      * first to the output data */
348     if ((*flags) & WIND_RW_BOM) {
349 	uint16_t bom = 0xfffe;
350 
351 	if (len < 2)
352 	    return WIND_ERR_OVERRUN;
353 
354 	if ((*flags) & WIND_RW_LE) {
355 	    p[0] = (bom     ) & 0xff;
356 	    p[1] = (bom >> 8) & 0xff;
357 	} else {
358 	    p[1] = (bom     ) & 0xff;
359 	    p[0] = (bom >> 8) & 0xff;
360 	}
361 	len -= 2;
362     }
363 
364     while (in_len) {
365 	/** If the output wont fit into out_len, WIND_ERR_OVERRUN is returned */
366 	if (len < 2)
367 	    return WIND_ERR_OVERRUN;
368 	if ((*flags) & WIND_RW_LE) {
369 	    p[0] = (in[0]     ) & 0xff;
370 	    p[1] = (in[0] >> 8) & 0xff;
371 	} else {
372 	    p[1] = (in[0]     ) & 0xff;
373 	    p[0] = (in[0] >> 8) & 0xff;
374 	}
375 	len -= 2;
376 	in_len--;
377 	p += 2;
378 	in++;
379     }
380     *out_len -= len;
381     return 0;
382 }
383 
384 
385 /**
386  * Convert an UTF-8 string to an UCS2 string.
387  *
388  * @param in an UTF-8 string to convert.
389  * @param out the resulting UCS2 strint, must be at least
390  * wind_utf8ucs2_length() long.  If out is NULL, the function will
391  * calculate the needed space for the out variable (just like
392  * wind_utf8ucs2_length()).
393  * @param out_len before processing out_len should be the length of
394  * the out variable, after processing it will be the length of the out
395  * string.
396  *
397  * @return returns 0 on success, an wind error code otherwise
398  * @ingroup wind
399  */
400 
401 int
wind_utf8ucs2(const char * in,uint16_t * out,size_t * out_len)402 wind_utf8ucs2(const char *in, uint16_t *out, size_t *out_len)
403 {
404     const unsigned char *p;
405     size_t o = 0;
406     int ret;
407 
408     for (p = (const unsigned char *)in; *p != '\0'; ++p) {
409 	uint32_t u;
410 
411 	ret = utf8toutf32(&p, &u);
412 	if (ret)
413 	    return ret;
414 
415 	if (u & 0xffff0000)
416 	    return WIND_ERR_NOT_UTF16;
417 
418 	if (out) {
419 	    if (o >= *out_len)
420 		return WIND_ERR_OVERRUN;
421 	    out[o] = u;
422 	}
423 	o++;
424     }
425     *out_len = o;
426     return 0;
427 }
428 
429 /**
430  * Calculate the length of from converting a UTF-8 string to a UCS2
431  * string.
432  *
433  * @param in an UTF-8 string to convert.
434  * @param out_len the length of the resulting UCS4 string.
435  *
436  * @return returns 0 on success, an wind error code otherwise
437  * @ingroup wind
438  */
439 
440 int
wind_utf8ucs2_length(const char * in,size_t * out_len)441 wind_utf8ucs2_length(const char *in, size_t *out_len)
442 {
443     return wind_utf8ucs2(in, NULL, out_len);
444 }
445 
446 /**
447  * Convert an UCS2 string to a UTF-8 string.
448  *
449  * @param in an UCS2 string to convert.
450  * @param in_len the length of the in UCS2 string.
451  * @param out the resulting UTF-8 strint, must be at least
452  * wind_ucs2utf8_length() long.  If out is NULL, the function will
453  * calculate the needed space for the out variable (just like
454  * wind_ucs2utf8_length()).
455  * @param out_len before processing out_len should be the length of
456  * the out variable, after processing it will be the length of the out
457  * string.
458  *
459  * @return returns 0 on success, an wind error code otherwise
460  * @ingroup wind
461  */
462 
463 int
wind_ucs2utf8(const uint16_t * in,size_t in_len,char * out,size_t * out_len)464 wind_ucs2utf8(const uint16_t *in, size_t in_len, char *out, size_t *out_len)
465 {
466     uint16_t ch;
467     size_t i, len, o;
468 
469     for (o = 0, i = 0; i < in_len; i++) {
470 	ch = in[i];
471 
472 	if (ch < 0x80) {
473 	    len = 1;
474 	} else if (ch < 0x800) {
475 	    len = 2;
476 	} else
477 	    len = 3;
478 
479 	o += len;
480 
481 	if (out) {
482 	    if (o >= *out_len)
483 		return WIND_ERR_OVERRUN;
484 
485 	    switch(len) {
486 	    case 3:
487 		out[2] = (ch | 0x80) & 0xbf;
488 		ch = ch >> 6;
489                 /* FALLTHROUGH */
490 	    case 2:
491 		out[1] = (ch | 0x80) & 0xbf;
492 		ch = ch >> 6;
493                 /* FALLTHROUGH */
494 	    case 1:
495 		out[0] = ch | first_char[len - 1];
496                 /* FALLTHROUGH */
497 	    }
498 	    out += len;
499 	}
500     }
501     if (out) {
502 	if (o >= *out_len)
503 	    return WIND_ERR_OVERRUN;
504 	*out = '\0';
505     }
506     *out_len = o;
507     return 0;
508 }
509 
510 /**
511  * Calculate the length of from converting a UCS2 string to an UTF-8 string.
512  *
513  * @param in an UCS2 string to convert.
514  * @param in_len an UCS2 string length to convert.
515  * @param out_len the length of the resulting UTF-8 string.
516  *
517  * @return returns 0 on success, an wind error code otherwise
518  * @ingroup wind
519  */
520 
521 int
wind_ucs2utf8_length(const uint16_t * in,size_t in_len,size_t * out_len)522 wind_ucs2utf8_length(const uint16_t *in, size_t in_len, size_t *out_len)
523 {
524     return wind_ucs2utf8(in, in_len, NULL, out_len);
525 }
526