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