1 /*
2  * "streamable kanji code filter and converter"
3  * Copyright (c) 1998-2002 HappySize, Inc. All rights reserved.
4  *
5  * LICENSE NOTICES
6  *
7  * This file is part of "streamable kanji code filter and converter",
8  * which is distributed under the terms of GNU Lesser General Public
9  * License (version 2) as published by the Free Software Foundation.
10  *
11  * This software is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with "streamable kanji code filter and converter";
18  * if not, write to the Free Software Foundation, Inc., 59 Temple Place,
19  * Suite 330, Boston, MA  02111-1307  USA
20  *
21  * The author of this file:
22  *
23  */
24 /*
25  * The source code included in this files was separated from mbfilter.c
26  * by moriyoshi koizumi <moriyoshi@php.net> on 4 dec 2002.
27  *
28  */
29 
30 #include "mbfilter.h"
31 #include "mbfilter_utf7.h"
32 
33 static int mbfl_filt_conv_utf7_wchar_flush(mbfl_convert_filter *filter);
34 
35 static const unsigned char mbfl_base64_table[] = {
36  /* 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', */
37    0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x4b,0x4c,0x4d,
38  /* 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', */
39    0x4e,0x4f,0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5a,
40  /* 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', */
41    0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x6b,0x6c,0x6d,
42  /* 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', */
43    0x6e,0x6f,0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,
44  /* '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/', '\0' */
45    0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0x2b,0x2f,0x00
46 };
47 
48 static const char *mbfl_encoding_utf7_aliases[] = {"utf7", NULL};
49 
50 const mbfl_encoding mbfl_encoding_utf7 = {
51 	mbfl_no_encoding_utf7,
52 	"UTF-7",
53 	"UTF-7",
54 	mbfl_encoding_utf7_aliases,
55 	NULL,
56 	MBFL_ENCTYPE_GL_UNSAFE,
57 	&vtbl_utf7_wchar,
58 	&vtbl_wchar_utf7
59 };
60 
61 const struct mbfl_convert_vtbl vtbl_utf7_wchar = {
62 	mbfl_no_encoding_utf7,
63 	mbfl_no_encoding_wchar,
64 	mbfl_filt_conv_common_ctor,
65 	NULL,
66 	mbfl_filt_conv_utf7_wchar,
67 	mbfl_filt_conv_utf7_wchar_flush,
68 	NULL,
69 };
70 
71 const struct mbfl_convert_vtbl vtbl_wchar_utf7 = {
72 	mbfl_no_encoding_wchar,
73 	mbfl_no_encoding_utf7,
74 	mbfl_filt_conv_common_ctor,
75 	NULL,
76 	mbfl_filt_conv_wchar_utf7,
77 	mbfl_filt_conv_wchar_utf7_flush,
78 	NULL,
79 };
80 
81 
82 #define CK(statement)	do { if ((statement) < 0) return (-1); } while (0)
83 
decode_base64_char(unsigned char c)84 static unsigned int decode_base64_char(unsigned char c)
85 {
86 	if (c >= 'A' && c <= 'Z') {
87 		return c - 65;
88 	} else if (c >= 'a' && c <= 'z') {
89 		return c - 71;
90 	} else if (c >= '0' && c <= '9') {
91 		return c + 4;
92 	} else if (c == '+') {
93 		return 62;
94 	} else if (c == '/') {
95 		return 63;
96 	}
97 	return -1;
98 }
99 
mbfl_filt_conv_utf7_wchar(int c,mbfl_convert_filter * filter)100 int mbfl_filt_conv_utf7_wchar(int c, mbfl_convert_filter *filter)
101 {
102 	int s, n = -1;
103 
104 	if (filter->status) { /* Modified Base64 */
105 		n = decode_base64_char(c);
106 		if (n < 0) {
107 			if (filter->cache) {
108 				/* Either we were expecting the 2nd half of a surrogate pair which
109 				 * never came, or else the last Base64 data was not padded with zeroes */
110 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
111 			}
112 			if (c == '-') {
113 				if (filter->status == 1) { /* "+-" -> "+" */
114 					CK((*filter->output_function)('+', filter->data));
115 				}
116 			} else if (c >= 0 && c < 0x80) { /* ASCII exclude '-' */
117 				CK((*filter->output_function)(c, filter->data));
118 			} else { /* illegal character */
119 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
120 			}
121 			filter->cache = filter->status = 0;
122 			return 0;
123 		}
124 	}
125 
126 	switch (filter->status) {
127 	/* directly encoded characters */
128 	case 0:
129 		if (c == '+') { /* '+' shift character */
130 			filter->status = 1;
131 		} else if (c >= 0 && c < 0x80) { /* ASCII */
132 			CK((*filter->output_function)(c, filter->data));
133 		} else { /* illegal character */
134 			CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
135 		}
136 		break;
137 
138 	/* decode Modified Base64 */
139 	case 1:
140 	case 2:
141 		filter->cache |= n << 10;
142 		filter->status = 3;
143 		break;
144 	case 3:
145 		filter->cache |= n << 4;
146 		filter->status = 4;
147 		break;
148 	case 4:
149 		s = ((n >> 2) & 0xf) | (filter->cache & 0xffff);
150 		n = (n & 0x3) << 14;
151 		filter->status = 5;
152 		if (s >= 0xd800 && s < 0xdc00) {
153 			/* 1st part of surrogate pair */
154 			if (filter->cache & 0xfff0000) {
155 				/* We were waiting for the 2nd part of a surrogate pair */
156 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
157 			}
158 			s = (((s & 0x3ff) << 16) + 0x400000) | n;
159 			filter->cache = s;
160 		} else if (s >= 0xdc00 && s < 0xe000) {
161 			/* 2nd part of surrogate pair */
162 			if (filter->cache & 0xfff0000) {
163 				s &= 0x3ff;
164 				s |= (filter->cache & 0xfff0000) >> 6;
165 				filter->cache = n;
166 				if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
167 					CK((*filter->output_function)(s, filter->data));
168 				} else { /* illegal character */
169 					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
170 				}
171 			} else {
172 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
173 				filter->cache = n;
174 			}
175 		} else {
176 			if (filter->cache & 0xfff0000) {
177 				/* We were waiting for the 2nd part of a surrogate pair */
178 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
179 			}
180 			filter->cache = n;
181 			CK((*filter->output_function)(s, filter->data));
182 		}
183 		break;
184 
185 	case 5:
186 		filter->cache |= n << 8;
187 		filter->status = 6;
188 		break;
189 	case 6:
190 		filter->cache |= n << 2;
191 		filter->status = 7;
192 		break;
193 	case 7:
194 		s = ((n >> 4) & 0x3) | (filter->cache & 0xffff);
195 		n = (n & 0xf) << 12;
196 		filter->status = 8;
197 		if (s >= 0xd800 && s < 0xdc00) {
198 			if (filter->cache & 0xfff0000) {
199 				/* We were waiting for the 2nd part of a surrogate pair */
200 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
201 			}
202 			s = (((s & 0x3ff) << 16) + 0x400000) | n;
203 			filter->cache = s;
204 		} else if (s >= 0xdc00 && s < 0xe000) {
205 			/* 2nd part of surrogate pair */
206 			if (filter->cache & 0xfff0000) {
207 				s &= 0x3ff;
208 				s |= (filter->cache & 0xfff0000) >> 6;
209 				filter->cache = n;
210 				if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
211 					CK((*filter->output_function)(s, filter->data));
212 				} else { /* illegal character */
213 					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
214 				}
215 			} else {
216 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
217 				filter->cache = n;
218 			}
219 		} else {
220 			if (filter->cache & 0xfff0000) {
221 				/* We were waiting for the 2nd part of a surrogate pair */
222 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
223 			}
224 			filter->cache = n;
225 			CK((*filter->output_function)(s, filter->data));
226 		}
227 		break;
228 
229 	case 8:
230 		filter->cache |= n << 6;
231 		filter->status = 9;
232 		break;
233 	case 9:
234 		s = n | (filter->cache & 0xffff);
235 		filter->status = 2;
236 		if (s >= 0xd800 && s < 0xdc00) {
237 			if (filter->cache & 0xfff0000) {
238 				/* We were waiting for the 2nd part of a surrogate pair */
239 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
240 			}
241 			s = (((s & 0x3ff) << 16) + 0x400000);
242 			filter->cache = s;
243 		} else if (s >= 0xdc00 && s < 0xe000) {
244 			if (filter->cache & 0xfff0000) {
245 				s &= 0x3ff;
246 				s |= (filter->cache & 0xfff0000) >> 6;
247 				filter->cache = 0;
248 				if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
249 					CK((*filter->output_function)(s, filter->data));
250 				} else { /* illegal character */
251 					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
252 				}
253 			} else {
254 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
255 				filter->cache = 0;
256 			}
257 		} else {
258 			if (filter->cache & 0xfff0000) {
259 				/* We were waiting for the 2nd part of a surrogate pair */
260 				(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
261 			}
262 			filter->cache = 0;
263 			CK((*filter->output_function)(s, filter->data));
264 		}
265 		break;
266 
267 	default:
268 		filter->status = 0;
269 		break;
270 	}
271 
272 	return 0;
273 }
274 
mbfl_filt_conv_utf7_wchar_flush(mbfl_convert_filter * filter)275 static int mbfl_filt_conv_utf7_wchar_flush(mbfl_convert_filter *filter)
276 {
277 	if (filter->cache) {
278 		/* Either we were expecting the 2nd half of a surrogate pair which
279 		 * never came, or else the last Base64 data was not padded with zeroes */
280 		(*filter->output_function)(MBFL_BAD_INPUT, filter->data);
281 	}
282 
283 	if (filter->flush_function) {
284 		(*filter->flush_function)(filter->data);
285 	}
286 
287 	return 0;
288 }
289 
mbfl_filt_conv_wchar_utf7(int c,mbfl_convert_filter * filter)290 int mbfl_filt_conv_wchar_utf7(int c, mbfl_convert_filter *filter)
291 {
292 	int s;
293 
294 	int n = 0;
295 	if (c >= 0 && c < 0x80) { /* ASCII */
296 		if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '\0' || c == '/' || c == '-') {
297 			n = 1;
298 		} else if (c == ' ' || c == '\t' || c == '\r' || c == '\n' || c == '\'' || c == '(' || c == ')' || c == ',' || c == '.' || c == ':' || c == '?') {
299 			n = 2;
300 		}
301 	} else if (c >= 0 && c < MBFL_WCSPLANE_UCS2MAX) {
302 		;
303 	} else if (c >= MBFL_WCSPLANE_SUPMIN && c < MBFL_WCSPLANE_SUPMAX) {
304 		CK((*filter->filter_function)(((c >> 10) - 0x40) | 0xd800, filter));
305 		CK((*filter->filter_function)((c & 0x3ff) | 0xdc00, filter));
306 		return 0;
307 	} else {
308 		CK(mbfl_filt_conv_illegal_output(c, filter));
309 		return 0;
310 	}
311 
312 	switch (filter->status) {
313 	case 0:
314 		if (n != 0) { /* directly encode characters */
315 			CK((*filter->output_function)(c, filter->data));
316 		} else { /* Modified Base64 */
317 			CK((*filter->output_function)('+', filter->data));
318 			filter->status = 1;
319 			filter->cache = c;
320 		}
321 		break;
322 
323 	/* encode Modified Base64 */
324 	case 1:
325 		s = filter->cache;
326 		CK((*filter->output_function)(mbfl_base64_table[(s >> 10) & 0x3f], filter->data));
327 		CK((*filter->output_function)(mbfl_base64_table[(s >> 4) & 0x3f], filter->data));
328 		if (n != 0) {
329 			CK((*filter->output_function)(mbfl_base64_table[(s << 2) & 0x3c], filter->data));
330 			if (n == 1) {
331 				CK((*filter->output_function)('-', filter->data));
332 			}
333 			CK((*filter->output_function)(c, filter->data));
334 			filter->status = 0;
335 		} else {
336 			filter->status = 2;
337 			filter->cache = ((s & 0xf) << 16) | c;
338 		}
339 		break;
340 
341 	case 2:
342 		s = filter->cache;
343 		CK((*filter->output_function)(mbfl_base64_table[(s >> 14) & 0x3f], filter->data));
344 		CK((*filter->output_function)(mbfl_base64_table[(s >> 8) & 0x3f], filter->data));
345 		CK((*filter->output_function)(mbfl_base64_table[(s >> 2) & 0x3f], filter->data));
346 		if (n != 0) {
347 			CK((*filter->output_function)(mbfl_base64_table[(s << 4) & 0x30], filter->data));
348 			if (n == 1) {
349 				CK((*filter->output_function)('-', filter->data));
350 			}
351 			CK((*filter->output_function)(c, filter->data));
352 			filter->status = 0;
353 		} else {
354 			filter->status = 3;
355 			filter->cache = ((s & 0x3) << 16) | c;
356 		}
357 		break;
358 
359 	case 3:
360 		s = filter->cache;
361 		CK((*filter->output_function)(mbfl_base64_table[(s >> 12) & 0x3f], filter->data));
362 		CK((*filter->output_function)(mbfl_base64_table[(s >> 6) & 0x3f], filter->data));
363 		CK((*filter->output_function)(mbfl_base64_table[s & 0x3f], filter->data));
364 		if (n != 0) {
365 			if (n == 1) {
366 				CK((*filter->output_function)('-', filter->data));
367 			}
368 			CK((*filter->output_function)(c, filter->data));
369 			filter->status = 0;
370 		} else {
371 			filter->status = 1;
372 			filter->cache = c;
373 		}
374 		break;
375 
376 	default:
377 		filter->status = 0;
378 		break;
379 	}
380 
381 	return 0;
382 }
383 
mbfl_filt_conv_wchar_utf7_flush(mbfl_convert_filter * filter)384 int mbfl_filt_conv_wchar_utf7_flush(mbfl_convert_filter *filter)
385 {
386 	int status = filter->status;
387 	int cache = filter->cache;
388 
389 	/* flush fragments */
390 	switch (status) {
391 	case 1:
392 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 10) & 0x3f], filter->data));
393 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 4) & 0x3f], filter->data));
394 		CK((*filter->output_function)(mbfl_base64_table[(cache << 2) & 0x3c], filter->data));
395 		CK((*filter->output_function)('-', filter->data));
396 		break;
397 
398 	case 2:
399 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 14) & 0x3f], filter->data));
400 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 8) & 0x3f], filter->data));
401 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 2) & 0x3f], filter->data));
402 		CK((*filter->output_function)(mbfl_base64_table[(cache << 4) & 0x30], filter->data));
403 		CK((*filter->output_function)('-', filter->data));
404 		break;
405 
406 	case 3:
407 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 12) & 0x3f], filter->data));
408 		CK((*filter->output_function)(mbfl_base64_table[(cache >> 6) & 0x3f], filter->data));
409 		CK((*filter->output_function)(mbfl_base64_table[cache & 0x3f], filter->data));
410 		CK((*filter->output_function)('-', filter->data));
411 		break;
412 	}
413 
414 	if (filter->flush_function) {
415 		(*filter->flush_function)(filter->data);
416 	}
417 
418 	return 0;
419 }
420