1/* crypto/asn1/a_utf8.c */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to.  The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 *    notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 *    notice, this list of conditions and the following disclaimer in the
30 *    documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 *    must display the following acknowledgement:
33 *    "This product includes cryptographic software written by
34 *     Eric Young (eay@cryptsoft.com)"
35 *    The word 'cryptographic' can be left out if the rouines from the library
36 *    being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 *    the apps directory (application code) you must include an acknowledgement:
39 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed.  i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59#include <stdio.h>
60#include "cryptlib.h"
61#include <openssl/asn1.h>
62
63
64/* UTF8 utilities */
65
66/* This parses a UTF8 string one character at a time. It is passed a pointer
67 * to the string and the length of the string. It sets 'value' to the value of
68 * the current character. It returns the number of characters read or a
69 * negative error code:
70 * -1 = string too short
71 * -2 = illegal character
72 * -3 = subsequent characters not of the form 10xxxxxx
73 * -4 = character encoded incorrectly (not minimal length).
74 */
75
76int UTF8_getc(const unsigned char *str, int len, unsigned long *val)
77{
78	const unsigned char *p;
79	unsigned long value;
80	int ret;
81	if(len <= 0) return 0;
82	p = str;
83
84	/* Check syntax and work out the encoded value (if correct) */
85	if((*p & 0x80) == 0) {
86		value = *p++ & 0x7f;
87		ret = 1;
88	} else if((*p & 0xe0) == 0xc0) {
89		if(len < 2) return -1;
90		if((p[1] & 0xc0) != 0x80) return -3;
91		value = (*p++ & 0x1f) << 6;
92		value |= *p++ & 0x3f;
93		if(value < 0x80) return -4;
94		ret = 2;
95	} else if((*p & 0xf0) == 0xe0) {
96		if(len < 3) return -1;
97		if( ((p[1] & 0xc0) != 0x80)
98		   || ((p[2] & 0xc0) != 0x80) ) return -3;
99		value = (*p++ & 0xf) << 12;
100		value |= (*p++ & 0x3f) << 6;
101		value |= *p++ & 0x3f;
102		if(value < 0x800) return -4;
103		ret = 3;
104	} else if((*p & 0xf8) == 0xf0) {
105		if(len < 4) return -1;
106		if( ((p[1] & 0xc0) != 0x80)
107		   || ((p[2] & 0xc0) != 0x80)
108		   || ((p[3] & 0xc0) != 0x80) ) return -3;
109		value = ((unsigned long)(*p++ & 0x7)) << 18;
110		value |= (*p++ & 0x3f) << 12;
111		value |= (*p++ & 0x3f) << 6;
112		value |= *p++ & 0x3f;
113		if(value < 0x10000) return -4;
114		ret = 4;
115	} else if((*p & 0xfc) == 0xf8) {
116		if(len < 5) return -1;
117		if( ((p[1] & 0xc0) != 0x80)
118		   || ((p[2] & 0xc0) != 0x80)
119		   || ((p[3] & 0xc0) != 0x80)
120		   || ((p[4] & 0xc0) != 0x80) ) return -3;
121		value = ((unsigned long)(*p++ & 0x3)) << 24;
122		value |= ((unsigned long)(*p++ & 0x3f)) << 18;
123		value |= ((unsigned long)(*p++ & 0x3f)) << 12;
124		value |= (*p++ & 0x3f) << 6;
125		value |= *p++ & 0x3f;
126		if(value < 0x200000) return -4;
127		ret = 5;
128	} else if((*p & 0xfe) == 0xfc) {
129		if(len < 6) return -1;
130		if( ((p[1] & 0xc0) != 0x80)
131		   || ((p[2] & 0xc0) != 0x80)
132		   || ((p[3] & 0xc0) != 0x80)
133		   || ((p[4] & 0xc0) != 0x80)
134		   || ((p[5] & 0xc0) != 0x80) ) return -3;
135		value = ((unsigned long)(*p++ & 0x1)) << 30;
136		value |= ((unsigned long)(*p++ & 0x3f)) << 24;
137		value |= ((unsigned long)(*p++ & 0x3f)) << 18;
138		value |= ((unsigned long)(*p++ & 0x3f)) << 12;
139		value |= (*p++ & 0x3f) << 6;
140		value |= *p++ & 0x3f;
141		if(value < 0x4000000) return -4;
142		ret = 6;
143	} else return -2;
144	*val = value;
145	return ret;
146}
147
148/* This takes a character 'value' and writes the UTF8 encoded value in
149 * 'str' where 'str' is a buffer containing 'len' characters. Returns
150 * the number of characters written or -1 if 'len' is too small. 'str' can
151 * be set to NULL in which case it just returns the number of characters.
152 * It will need at most 6 characters.
153 */
154
155int UTF8_putc(unsigned char *str, int len, unsigned long value)
156{
157	if(!str) len = 6;	/* Maximum we will need */
158	else if(len <= 0) return -1;
159	if(value < 0x80) {
160		if(str) *str = (unsigned char)value;
161		return 1;
162	}
163	if(value < 0x800) {
164		if(len < 2) return -1;
165		if(str) {
166			*str++ = (unsigned char)(((value >> 6) & 0x1f) | 0xc0);
167			*str = (unsigned char)((value & 0x3f) | 0x80);
168		}
169		return 2;
170	}
171	if(value < 0x10000) {
172		if(len < 3) return -1;
173		if(str) {
174			*str++ = (unsigned char)(((value >> 12) & 0xf) | 0xe0);
175			*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
176			*str = (unsigned char)((value & 0x3f) | 0x80);
177		}
178		return 3;
179	}
180	if(value < 0x200000) {
181		if(len < 4) return -1;
182		if(str) {
183			*str++ = (unsigned char)(((value >> 18) & 0x7) | 0xf0);
184			*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);
185			*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
186			*str = (unsigned char)((value & 0x3f) | 0x80);
187		}
188		return 4;
189	}
190	if(value < 0x4000000) {
191		if(len < 5) return -1;
192		if(str) {
193			*str++ = (unsigned char)(((value >> 24) & 0x3) | 0xf8);
194			*str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80);
195			*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);
196			*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
197			*str = (unsigned char)((value & 0x3f) | 0x80);
198		}
199		return 5;
200	}
201	if(len < 6) return -1;
202	if(str) {
203		*str++ = (unsigned char)(((value >> 30) & 0x1) | 0xfc);
204		*str++ = (unsigned char)(((value >> 24) & 0x3f) | 0x80);
205		*str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80);
206		*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);
207		*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
208		*str = (unsigned char)((value & 0x3f) | 0x80);
209	}
210	return 6;
211}
212