openldap/libraries/libldap/utf-8.c
Quanah Gibson-Mount f6ad222e41 Happy New Year!
2020-01-09 16:50:21 +00:00

563 lines
12 KiB
C

/* utf-8.c -- Basic UTF-8 routines */
/* $OpenLDAP$ */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
*
* Copyright 1998-2020 The OpenLDAP Foundation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted only as authorized by the OpenLDAP
* Public License.
*
* A copy of this license is available in the file LICENSE in the
* top-level directory of the distribution or, alternatively, at
* <http://www.OpenLDAP.org/license.html>.
*/
/* Basic UTF-8 routines
*
* These routines are "dumb". Though they understand UTF-8,
* they don't grok Unicode. That is, they can push bits,
* but don't have a clue what the bits represent. That's
* good enough for use with the LDAP Client SDK.
*
* These routines are not optimized.
*/
#include "portable.h"
#include <stdio.h>
#include <ac/stdlib.h>
#include <ac/socket.h>
#include <ac/string.h>
#include <ac/time.h>
#include "ldap_utf8.h"
#include "ldap-int.h"
#include "ldap_defaults.h"
/*
* return the number of bytes required to hold the
* NULL-terminated UTF-8 string NOT INCLUDING the
* termination.
*/
ber_len_t ldap_utf8_bytes( const char * p )
{
ber_len_t bytes;
for( bytes=0; p[bytes]; bytes++ ) {
/* EMPTY */ ;
}
return bytes;
}
ber_len_t ldap_utf8_chars( const char * p )
{
/* could be optimized and could check for invalid sequences */
ber_len_t chars=0;
for( ; *p ; LDAP_UTF8_INCR(p) ) {
chars++;
}
return chars;
}
/* return offset to next character */
int ldap_utf8_offset( const char * p )
{
return LDAP_UTF8_NEXT(p) - p;
}
/*
* Returns length indicated by first byte.
*/
const char ldap_utf8_lentab[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 0, 0 };
int ldap_utf8_charlen( const char * p )
{
if (!(*p & 0x80))
return 1;
return ldap_utf8_lentab[*(const unsigned char *)p ^ 0x80];
}
/*
* Make sure the UTF-8 char used the shortest possible encoding
* returns charlen if valid, 0 if not.
*
* Here are the valid UTF-8 encodings, taken from RFC 2279 page 4.
* The table is slightly modified from that of the RFC.
*
* UCS-4 range (hex) UTF-8 sequence (binary)
* 0000 0000-0000 007F 0.......
* 0000 0080-0000 07FF 110++++. 10......
* 0000 0800-0000 FFFF 1110++++ 10+..... 10......
* 0001 0000-001F FFFF 11110+++ 10++.... 10...... 10......
* 0020 0000-03FF FFFF 111110++ 10+++... 10...... 10...... 10......
* 0400 0000-7FFF FFFF 1111110+ 10++++.. 10...... 10...... 10...... 10......
*
* The '.' bits are "don't cares". When validating a UTF-8 sequence,
* at least one of the '+' bits must be set, otherwise the character
* should have been encoded in fewer octets. Note that in the two-octet
* case, only the first octet needs to be validated, and this is done
* in the ldap_utf8_lentab[] above.
*/
/* mask of required bits in second octet */
#undef c
#define c const char
c ldap_utf8_mintab[] = {
(c)0x20, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80,
(c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80,
(c)0x30, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80, (c)0x80,
(c)0x38, (c)0x80, (c)0x80, (c)0x80, (c)0x3c, (c)0x80, (c)0x00, (c)0x00 };
#undef c
int ldap_utf8_charlen2( const char * p )
{
int i = LDAP_UTF8_CHARLEN( p );
if ( i > 2 ) {
if ( !( ldap_utf8_mintab[*p & 0x1f] & p[1] ) )
i = 0;
}
return i;
}
/* conv UTF-8 to UCS-4, useful for comparisons */
ldap_ucs4_t ldap_x_utf8_to_ucs4( const char * p )
{
const unsigned char *c = (const unsigned char *) p;
ldap_ucs4_t ch;
int len, i;
static unsigned char mask[] = {
0, 0x7f, 0x1f, 0x0f, 0x07, 0x03, 0x01 };
len = LDAP_UTF8_CHARLEN2(p, len);
if( len == 0 ) return LDAP_UCS4_INVALID;
ch = c[0] & mask[len];
for(i=1; i < len; i++) {
if ((c[i] & 0xc0) != 0x80) {
return LDAP_UCS4_INVALID;
}
ch <<= 6;
ch |= c[i] & 0x3f;
}
return ch;
}
/* conv UCS-4 to UTF-8, not used */
int ldap_x_ucs4_to_utf8( ldap_ucs4_t c, char *buf )
{
int len=0;
unsigned char* p = (unsigned char *) buf;
/* not a valid Unicode character */
if ( c < 0 ) return 0;
/* Just return length, don't convert */
if(buf == NULL) {
if( c < 0x80 ) return 1;
else if( c < 0x800 ) return 2;
else if( c < 0x10000 ) return 3;
else if( c < 0x200000 ) return 4;
else if( c < 0x4000000 ) return 5;
else return 6;
}
if( c < 0x80 ) {
p[len++] = c;
} else if( c < 0x800 ) {
p[len++] = 0xc0 | ( c >> 6 );
p[len++] = 0x80 | ( c & 0x3f );
} else if( c < 0x10000 ) {
p[len++] = 0xe0 | ( c >> 12 );
p[len++] = 0x80 | ( (c >> 6) & 0x3f );
p[len++] = 0x80 | ( c & 0x3f );
} else if( c < 0x200000 ) {
p[len++] = 0xf0 | ( c >> 18 );
p[len++] = 0x80 | ( (c >> 12) & 0x3f );
p[len++] = 0x80 | ( (c >> 6) & 0x3f );
p[len++] = 0x80 | ( c & 0x3f );
} else if( c < 0x4000000 ) {
p[len++] = 0xf8 | ( c >> 24 );
p[len++] = 0x80 | ( (c >> 18) & 0x3f );
p[len++] = 0x80 | ( (c >> 12) & 0x3f );
p[len++] = 0x80 | ( (c >> 6) & 0x3f );
p[len++] = 0x80 | ( c & 0x3f );
} else /* if( c < 0x80000000 ) */ {
p[len++] = 0xfc | ( c >> 30 );
p[len++] = 0x80 | ( (c >> 24) & 0x3f );
p[len++] = 0x80 | ( (c >> 18) & 0x3f );
p[len++] = 0x80 | ( (c >> 12) & 0x3f );
p[len++] = 0x80 | ( (c >> 6) & 0x3f );
p[len++] = 0x80 | ( c & 0x3f );
}
return len;
}
#define LDAP_UCS_UTF8LEN(c) \
c < 0 ? 0 : (c < 0x80 ? 1 : (c < 0x800 ? 2 : (c < 0x10000 ? 3 : \
(c < 0x200000 ? 4 : (c < 0x4000000 ? 5 : 6)))))
/* Convert a string to UTF-8 format. The input string is expected to
* have characters of 1, 2, or 4 octets (in network byte order)
* corresponding to the ASN.1 T61STRING, BMPSTRING, and UNIVERSALSTRING
* types respectively. (Here T61STRING just means that there is one
* octet per character and characters may use the high bit of the octet.
* The characters are assumed to use ISO mappings, no provision is made
* for converting from T.61 coding rules to Unicode.)
*/
int
ldap_ucs_to_utf8s( struct berval *ucs, int csize, struct berval *utf8s )
{
unsigned char *in, *end;
char *ptr;
ldap_ucs4_t u;
int i, l = 0;
utf8s->bv_val = NULL;
utf8s->bv_len = 0;
in = (unsigned char *)ucs->bv_val;
/* Make sure we stop at an even multiple of csize */
end = in + ( ucs->bv_len & ~(csize-1) );
for (; in < end; ) {
u = *in++;
if (csize > 1) {
u <<= 8;
u |= *in++;
}
if (csize > 2) {
u <<= 8;
u |= *in++;
u <<= 8;
u |= *in++;
}
i = LDAP_UCS_UTF8LEN(u);
if (i == 0)
return LDAP_INVALID_SYNTAX;
l += i;
}
utf8s->bv_val = LDAP_MALLOC( l+1 );
if (utf8s->bv_val == NULL)
return LDAP_NO_MEMORY;
utf8s->bv_len = l;
ptr = utf8s->bv_val;
for (in = (unsigned char *)ucs->bv_val; in < end; ) {
u = *in++;
if (csize > 1) {
u <<= 8;
u |= *in++;
}
if (csize > 2) {
u <<= 8;
u |= *in++;
u <<= 8;
u |= *in++;
}
ptr += ldap_x_ucs4_to_utf8(u, ptr);
}
*ptr = '\0';
return LDAP_SUCCESS;
}
/*
* Advance to the next UTF-8 character
*
* Ignores length of multibyte character, instead rely on
* continuation markers to find start of next character.
* This allows for "resyncing" of when invalid characters
* are provided provided the start of the next character
* is appears within the 6 bytes examined.
*/
char* ldap_utf8_next( const char * p )
{
int i;
const unsigned char *u = (const unsigned char *) p;
if( LDAP_UTF8_ISASCII(u) ) {
return (char *) &p[1];
}
for( i=1; i<6; i++ ) {
if ( ( u[i] & 0xc0 ) != 0x80 ) {
return (char *) &p[i];
}
}
return (char *) &p[i];
}
/*
* Advance to the previous UTF-8 character
*
* Ignores length of multibyte character, instead rely on
* continuation markers to find start of next character.
* This allows for "resyncing" of when invalid characters
* are provided provided the start of the next character
* is appears within the 6 bytes examined.
*/
char* ldap_utf8_prev( const char * p )
{
int i;
const unsigned char *u = (const unsigned char *) p;
for( i=-1; i>-6 ; i-- ) {
if ( ( u[i] & 0xc0 ) != 0x80 ) {
return (char *) &p[i];
}
}
return (char *) &p[i];
}
/*
* Copy one UTF-8 character from src to dst returning
* number of bytes copied.
*
* Ignores length of multibyte character, instead rely on
* continuation markers to find start of next character.
* This allows for "resyncing" of when invalid characters
* are provided provided the start of the next character
* is appears within the 6 bytes examined.
*/
int ldap_utf8_copy( char* dst, const char *src )
{
int i;
const unsigned char *u = (const unsigned char *) src;
dst[0] = src[0];
if( LDAP_UTF8_ISASCII(u) ) {
return 1;
}
for( i=1; i<6; i++ ) {
if ( ( u[i] & 0xc0 ) != 0x80 ) {
return i;
}
dst[i] = src[i];
}
return i;
}
#ifndef UTF8_ALPHA_CTYPE
/*
* UTF-8 ctype routines
* Only deals with characters < 0x80 (ie: US-ASCII)
*/
int ldap_utf8_isascii( const char * p )
{
unsigned c = * (const unsigned char *) p;
return LDAP_ASCII(c);
}
int ldap_utf8_isdigit( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
return LDAP_DIGIT( c );
}
int ldap_utf8_isxdigit( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
return LDAP_HEX(c);
}
int ldap_utf8_isspace( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
switch(c) {
case ' ':
case '\t':
case '\n':
case '\r':
case '\v':
case '\f':
return 1;
}
return 0;
}
/*
* These are not needed by the C SDK and are
* not "good enough" for general use.
*/
int ldap_utf8_isalpha( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
return LDAP_ALPHA(c);
}
int ldap_utf8_isalnum( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
return LDAP_ALNUM(c);
}
int ldap_utf8_islower( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
return LDAP_LOWER(c);
}
int ldap_utf8_isupper( const char * p )
{
unsigned c = * (const unsigned char *) p;
if(!LDAP_ASCII(c)) return 0;
return LDAP_UPPER(c);
}
#endif
/*
* UTF-8 string routines
*/
/* like strchr() */
char * (ldap_utf8_strchr)( const char *str, const char *chr )
{
for( ; *str != '\0'; LDAP_UTF8_INCR(str) ) {
if( ldap_x_utf8_to_ucs4( str ) == ldap_x_utf8_to_ucs4( chr ) ) {
return (char *) str;
}
}
return NULL;
}
/* like strcspn() but returns number of bytes, not characters */
ber_len_t (ldap_utf8_strcspn)( const char *str, const char *set )
{
const char *cstr;
const char *cset;
for( cstr = str; *cstr != '\0'; LDAP_UTF8_INCR(cstr) ) {
for( cset = set; *cset != '\0'; LDAP_UTF8_INCR(cset) ) {
if( ldap_x_utf8_to_ucs4( cstr ) == ldap_x_utf8_to_ucs4( cset ) ) {
return cstr - str;
}
}
}
return cstr - str;
}
/* like strspn() but returns number of bytes, not characters */
ber_len_t (ldap_utf8_strspn)( const char *str, const char *set )
{
const char *cstr;
const char *cset;
for( cstr = str; *cstr != '\0'; LDAP_UTF8_INCR(cstr) ) {
for( cset = set; ; LDAP_UTF8_INCR(cset) ) {
if( *cset == '\0' ) {
return cstr - str;
}
if( ldap_x_utf8_to_ucs4( cstr ) == ldap_x_utf8_to_ucs4( cset ) ) {
break;
}
}
}
return cstr - str;
}
/* like strpbrk(), replaces strchr() as well */
char *(ldap_utf8_strpbrk)( const char *str, const char *set )
{
for( ; *str != '\0'; LDAP_UTF8_INCR(str) ) {
const char *cset;
for( cset = set; *cset != '\0'; LDAP_UTF8_INCR(cset) ) {
if( ldap_x_utf8_to_ucs4( str ) == ldap_x_utf8_to_ucs4( cset ) ) {
return (char *) str;
}
}
}
return NULL;
}
/* like strtok_r(), not strtok() */
char *(ldap_utf8_strtok)(char *str, const char *sep, char **last)
{
char *begin;
char *end;
if( last == NULL ) return NULL;
begin = str ? str : *last;
begin += ldap_utf8_strspn( begin, sep );
if( *begin == '\0' ) {
*last = NULL;
return NULL;
}
end = &begin[ ldap_utf8_strcspn( begin, sep ) ];
if( *end != '\0' ) {
char *next = LDAP_UTF8_NEXT( end );
*end = '\0';
end = next;
}
*last = end;
return begin;
}