openssl/crypto/asn1/a_utf8.c

189 lines
5.9 KiB
C

/*
* Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/asn1.h>
/* UTF8 utilities */
/*-
* This parses a UTF8 string one character at a time. It is passed a pointer
* to the string and the length of the string. It sets 'value' to the value of
* the current character. It returns the number of characters read or a
* negative error code:
* -1 = string too short
* -2 = illegal character
* -3 = subsequent characters not of the form 10xxxxxx
* -4 = character encoded incorrectly (not minimal length).
*/
int UTF8_getc(const unsigned char *str, int len, unsigned long *val)
{
const unsigned char *p;
unsigned long value;
int ret;
if (len <= 0)
return 0;
p = str;
/* Check syntax and work out the encoded value (if correct) */
if ((*p & 0x80) == 0) {
value = *p++ & 0x7f;
ret = 1;
} else if ((*p & 0xe0) == 0xc0) {
if (len < 2)
return -1;
if ((p[1] & 0xc0) != 0x80)
return -3;
value = (*p++ & 0x1f) << 6;
value |= *p++ & 0x3f;
if (value < 0x80)
return -4;
ret = 2;
} else if ((*p & 0xf0) == 0xe0) {
if (len < 3)
return -1;
if (((p[1] & 0xc0) != 0x80)
|| ((p[2] & 0xc0) != 0x80))
return -3;
value = (*p++ & 0xf) << 12;
value |= (*p++ & 0x3f) << 6;
value |= *p++ & 0x3f;
if (value < 0x800)
return -4;
ret = 3;
} else if ((*p & 0xf8) == 0xf0) {
if (len < 4)
return -1;
if (((p[1] & 0xc0) != 0x80)
|| ((p[2] & 0xc0) != 0x80)
|| ((p[3] & 0xc0) != 0x80))
return -3;
value = ((unsigned long)(*p++ & 0x7)) << 18;
value |= (*p++ & 0x3f) << 12;
value |= (*p++ & 0x3f) << 6;
value |= *p++ & 0x3f;
if (value < 0x10000)
return -4;
ret = 4;
} else if ((*p & 0xfc) == 0xf8) {
if (len < 5)
return -1;
if (((p[1] & 0xc0) != 0x80)
|| ((p[2] & 0xc0) != 0x80)
|| ((p[3] & 0xc0) != 0x80)
|| ((p[4] & 0xc0) != 0x80))
return -3;
value = ((unsigned long)(*p++ & 0x3)) << 24;
value |= ((unsigned long)(*p++ & 0x3f)) << 18;
value |= ((unsigned long)(*p++ & 0x3f)) << 12;
value |= (*p++ & 0x3f) << 6;
value |= *p++ & 0x3f;
if (value < 0x200000)
return -4;
ret = 5;
} else if ((*p & 0xfe) == 0xfc) {
if (len < 6)
return -1;
if (((p[1] & 0xc0) != 0x80)
|| ((p[2] & 0xc0) != 0x80)
|| ((p[3] & 0xc0) != 0x80)
|| ((p[4] & 0xc0) != 0x80)
|| ((p[5] & 0xc0) != 0x80))
return -3;
value = ((unsigned long)(*p++ & 0x1)) << 30;
value |= ((unsigned long)(*p++ & 0x3f)) << 24;
value |= ((unsigned long)(*p++ & 0x3f)) << 18;
value |= ((unsigned long)(*p++ & 0x3f)) << 12;
value |= (*p++ & 0x3f) << 6;
value |= *p++ & 0x3f;
if (value < 0x4000000)
return -4;
ret = 6;
} else
return -2;
*val = value;
return ret;
}
/*
* This takes a character 'value' and writes the UTF8 encoded value in 'str'
* where 'str' is a buffer containing 'len' characters. Returns the number of
* characters written or -1 if 'len' is too small. 'str' can be set to NULL
* in which case it just returns the number of characters. It will need at
* most 6 characters.
*/
int UTF8_putc(unsigned char *str, int len, unsigned long value)
{
if (!str)
len = 6; /* Maximum we will need */
else if (len <= 0)
return -1;
if (value < 0x80) {
if (str)
*str = (unsigned char)value;
return 1;
}
if (value < 0x800) {
if (len < 2)
return -1;
if (str) {
*str++ = (unsigned char)(((value >> 6) & 0x1f) | 0xc0);
*str = (unsigned char)((value & 0x3f) | 0x80);
}
return 2;
}
if (value < 0x10000) {
if (len < 3)
return -1;
if (str) {
*str++ = (unsigned char)(((value >> 12) & 0xf) | 0xe0);
*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
*str = (unsigned char)((value & 0x3f) | 0x80);
}
return 3;
}
if (value < 0x200000) {
if (len < 4)
return -1;
if (str) {
*str++ = (unsigned char)(((value >> 18) & 0x7) | 0xf0);
*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);
*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
*str = (unsigned char)((value & 0x3f) | 0x80);
}
return 4;
}
if (value < 0x4000000) {
if (len < 5)
return -1;
if (str) {
*str++ = (unsigned char)(((value >> 24) & 0x3) | 0xf8);
*str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80);
*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);
*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
*str = (unsigned char)((value & 0x3f) | 0x80);
}
return 5;
}
if (len < 6)
return -1;
if (str) {
*str++ = (unsigned char)(((value >> 30) & 0x1) | 0xfc);
*str++ = (unsigned char)(((value >> 24) & 0x3f) | 0x80);
*str++ = (unsigned char)(((value >> 18) & 0x3f) | 0x80);
*str++ = (unsigned char)(((value >> 12) & 0x3f) | 0x80);
*str++ = (unsigned char)(((value >> 6) & 0x3f) | 0x80);
*str = (unsigned char)((value & 0x3f) | 0x80);
}
return 6;
}