1 /* 2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (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