1 | /* |
2 | * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
5 | * this file except in compliance with the License. You can obtain a copy |
6 | * in the file LICENSE in the source distribution or at |
7 | * https://www.openssl.org/source/license.html |
8 | */ |
9 | |
10 | #include <stdio.h> |
11 | #include "internal/cryptlib.h" |
12 | #include <openssl/asn1.h> |
13 | |
14 | /* UTF8 utilities */ |
15 | |
16 | /*- |
17 | * This parses a UTF8 string one character at a time. It is passed a pointer |
18 | * to the string and the length of the string. It sets 'value' to the value of |
19 | * the current character. It returns the number of characters read or a |
20 | * negative error code: |
21 | * -1 = string too short |
22 | * -2 = illegal character |
23 | * -3 = subsequent characters not of the form 10xxxxxx |
24 | * -4 = character encoded incorrectly (not minimal length). |
25 | */ |
26 | |
27 | int UTF8_getc(const unsigned char *str, int len, unsigned long *val) |
28 | { |
29 | const unsigned char *p; |
30 | unsigned long value; |
31 | int ret; |
32 | if (len <= 0) |
33 | return 0; |
34 | p = str; |
35 | |
36 | /* Check syntax and work out the encoded value (if correct) */ |
37 | if ((*p & 0x80) == 0) { |
38 | value = *p++ & 0x7f; |
39 | ret = 1; |
40 | } else if ((*p & 0xe0) == 0xc0) { |
41 | if (len < 2) |
42 | return -1; |
43 | if ((p[1] & 0xc0) != 0x80) |
44 | return -3; |
45 | value = (*p++ & 0x1f) << 6; |
46 | value |= *p++ & 0x3f; |
47 | if (value < 0x80) |
48 | return -4; |
49 | ret = 2; |
50 | } else if ((*p & 0xf0) == 0xe0) { |
51 | if (len < 3) |
52 | return -1; |
53 | if (((p[1] & 0xc0) != 0x80) |
54 | || ((p[2] & 0xc0) != 0x80)) |
55 | return -3; |
56 | value = (*p++ & 0xf) << 12; |
57 | value |= (*p++ & 0x3f) << 6; |
58 | value |= *p++ & 0x3f; |
59 | if (value < 0x800) |
60 | return -4; |
61 | ret = 3; |
62 | } else if ((*p & 0xf8) == 0xf0) { |
63 | if (len < 4) |
64 | return -1; |
65 | if (((p[1] & 0xc0) != 0x80) |
66 | || ((p[2] & 0xc0) != 0x80) |
67 | || ((p[3] & 0xc0) != 0x80)) |
68 | return -3; |
69 | value = ((unsigned long)(*p++ & 0x7)) << 18; |
70 | value |= (*p++ & 0x3f) << 12; |
71 | value |= (*p++ & 0x3f) << 6; |
72 | value |= *p++ & 0x3f; |
73 | if (value < 0x10000) |
74 | return -4; |
75 | ret = 4; |
76 | } else if ((*p & 0xfc) == 0xf8) { |
77 | if (len < 5) |
78 | return -1; |
79 | if (((p[1] & 0xc0) != 0x80) |
80 | || ((p[2] & 0xc0) != 0x80) |
81 | || ((p[3] & 0xc0) != 0x80) |
82 | || ((p[4] & 0xc0) != 0x80)) |
83 | return -3; |
84 | value = ((unsigned long)(*p++ & 0x3)) << 24; |
85 | value |= ((unsigned long)(*p++ & 0x3f)) << 18; |
86 | value |= ((unsigned long)(*p++ & 0x3f)) << 12; |
87 | value |= (*p++ & 0x3f) << 6; |
88 | value |= *p++ & 0x3f; |
89 | if (value < 0x200000) |
90 | return -4; |
91 | ret = 5; |
92 | } else if ((*p & 0xfe) == 0xfc) { |
93 | if (len < 6) |
94 | return -1; |
95 | if (((p[1] & 0xc0) != 0x80) |
96 | || ((p[2] & 0xc0) != 0x80) |
97 | || ((p[3] & 0xc0) != 0x80) |
98 | || ((p[4] & 0xc0) != 0x80) |
99 | || ((p[5] & 0xc0) != 0x80)) |
100 | return -3; |
101 | value = ((unsigned long)(*p++ & 0x1)) << 30; |
102 | value |= ((unsigned long)(*p++ & 0x3f)) << 24; |
103 | value |= ((unsigned long)(*p++ & 0x3f)) << 18; |
104 | value |= ((unsigned long)(*p++ & 0x3f)) << 12; |
105 | value |= (*p++ & 0x3f) << 6; |
106 | value |= *p++ & 0x3f; |
107 | if (value < 0x4000000) |
108 | return -4; |
109 | ret = 6; |
110 | } else |
111 | return -2; |
112 | *val = value; |
113 | return ret; |
114 | } |
115 | |
116 | /* |
117 | * This takes a character 'value' and writes the UTF8 encoded value in 'str' |
118 | * where 'str' is a buffer containing 'len' characters. Returns the number of |
119 | * characters written or -1 if 'len' is too small. 'str' can be set to NULL |
120 | * in which case it just returns the number of characters. It will need at |
121 | * most 6 characters. |
122 | */ |
123 | |
124 | int UTF8_putc(unsigned char *str, int len, unsigned long value) |
125 | { |
126 | if (!str) |
127 | len = 6; /* Maximum we will need */ |
128 | else if (len <= 0) |
129 | return -1; |
130 | if (value < 0x80) { |
131 | if (str) |
132 | *str = (unsigned char)value; |
133 | return 1; |
134 | } |
135 | if (value < 0x800) { |
136 | if (len < 2) |
137 | return -1; |
138 | if (str) { |
139 | *str++ = (unsigned char)(((value >> 6) & 0x1f) | 0xc0); |
140 | *str = (unsigned char)((value & 0x3f) | 0x80); |
141 | } |
142 | return 2; |
143 | } |
144 | if (value < 0x10000) { |
145 | if (len < 3) |
146 | return -1; |
147 | if (str) { |
148 | *str++ = (unsigned char)(((value >> 12) & 0xf) | 0xe0); |
149 | *str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80); |
150 | *str = (unsigned char)((value & 0x3f) | 0x80); |
151 | } |
152 | return 3; |
153 | } |
154 | if (value < 0x200000) { |
155 | if (len < 4) |
156 | return -1; |
157 | if (str) { |
158 | *str++ = (unsigned char)(((value >> 18) & 0x7) | 0xf0); |
159 | *str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80); |
160 | *str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80); |
161 | *str = (unsigned char)((value & 0x3f) | 0x80); |
162 | } |
163 | return 4; |
164 | } |
165 | if (value < 0x4000000) { |
166 | if (len < 5) |
167 | return -1; |
168 | if (str) { |
169 | *str++ = (unsigned char)(((value >> 24) & 0x3) | 0xf8); |
170 | *str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80); |
171 | *str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80); |
172 | *str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80); |
173 | *str = (unsigned char)((value & 0x3f) | 0x80); |
174 | } |
175 | return 5; |
176 | } |
177 | if (len < 6) |
178 | return -1; |
179 | if (str) { |
180 | *str++ = (unsigned char)(((value >> 30) & 0x1) | 0xfc); |
181 | *str++ = (unsigned char)(((value >> 24) & 0x3f) | 0x80); |
182 | *str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80); |
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 6; |
188 | } |
189 | |