/*
* Copyright (c) 2013, Red Hat Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
* * Redistributions in binary form must reproduce the
* above copyright notice, this list of conditions and
* the following disclaimer in the documentation and/or
* other materials provided with the distribution.
* * The names of contributors to this software may not be
* used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
* THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* Author: Stef Walter <stefw@redhat.com>
*/
#include "config.h"
#include "buffer.h"
#include "debug.h"
#include "utf8.h"
#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
/*
* Some parts come from FreeBSD utf8.c
*
* Copyright (c) 2002-2004 Tim J. Robbins
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
static ssize_t
utf8_to_uchar (const char *str,
size_t len,
uint32_t *uc)
{
int ch, i, mask, want;
uint32_t lbound, uch;
assert (str != NULL);
assert (len > 0);
assert (uc != NULL);
if (((ch = (unsigned char)*str) & ~0x7f) == 0) {
/* Fast path for plain ASCII characters. */
*uc = ch;
return 1;
}
/*
* Determine the number of octets that make up this character
* from the first octet, and a mask that extracts the
* interesting bits of the first octet. We already know
* the character is at least two bytes long.
*
* We also specify a lower bound for the character code to
* detect redundant, non-"shortest form" encodings. For
* example, the sequence C0 80 is _not_ a legal representation
* of the null character. This enforces a 1-to-1 mapping
* between character codes and their multibyte representations.
*/
ch = (unsigned char)*str;
if ((ch & 0xe0) == 0xc0) {
mask = 0x1f;
want = 2;
lbound = 0x80;
} else if ((ch & 0xf0) == 0xe0) {
mask = 0x0f;
want = 3;
lbound = 0x800;
} else if ((ch & 0xf8) == 0xf0) {
mask = 0x07;
want = 4;
lbound = 0x10000;
} else if ((ch & 0xfc) == 0xf8) {
mask = 0x03;
want = 5;
lbound = 0x200000;
} else if ((ch & 0xfe) == 0xfc) {
mask = 0x01;
want = 6;
lbound = 0x4000000;
} else {
/*
* Malformed input; input is not UTF-8.
*/
return -1;
}
if (want > len) {
/* Incomplete multibyte sequence. */
return -1;
}
/*
* Decode the octet sequence representing the character in chunks
* of 6 bits, most significant first.
*/
uch = (unsigned char)*str++ & mask;
for (i = 1; i < want; i++) {
if ((*str & 0xc0) != 0x80) {
/*
* Malformed input; bad characters in the middle
* of a character.
*/
return -1;
}
uch <<= 6;
uch |= *str++ & 0x3f;
}
if (uch < lbound) {
/*
* Malformed input; redundant encoding.
*/
return -1;
}
if ((uch >= 0xd800 && uch <= 0xdfff) || uch > 0x10ffff) {
/*
* Malformed input; invalid code points.
*/
return -1;
}
*uc = uch;
return want;
}
static size_t
utf8_for_uchar (uint32_t uc,
char *str,
size_t len)
{
unsigned char lead;
int i, want;
assert (str != NULL);
assert (len >= 6);
if ((uc & ~0x7f) == 0) {
/* Fast path for plain ASCII characters. */
*str = (char)uc;
return 1;
}
/*
* Determine the number of octets needed to represent this character.
* We always output the shortest sequence possible. Also specify the
* first few bits of the first octet, which contains the information
* about the sequence length.
*/
if ((uc & ~0x7ff) == 0) {
lead = 0xc0;
want = 2;
} else if ((uc & ~0xffff) == 0) {
lead = 0xe0;
want = 3;
} else if ((uc & ~0x1fffff) == 0) {
lead = 0xf0;
want = 4;
} else if ((uc & ~0x3ffffff) == 0) {
lead = 0xf8;
want = 5;
} else if ((uc & ~0x7fffffff) == 0) {
lead = 0xfc;
want = 6;
} else {
return -1;
}
assert (want <= len);
/*
* Output the octets representing the character in chunks
* of 6 bits, least significant last. The first octet is
* a special case because it contains the sequence length
* information.
*/
for (i = want - 1; i > 0; i--) {
str[i] = (uc & 0x3f) | 0x80;
uc >>= 6;
}
*str = (uc & 0xff) | lead;
return want;
}
static ssize_t
ucs2be_to_uchar (const unsigned char *str,
size_t len,
uint32_t *wc)
{
assert (str != NULL);
assert (len != 0);
assert (wc != NULL);
if (len < 2)
return -1;
*wc = (str[0] << 8 | str[1]);
return 2;
}
static ssize_t
ucs4be_to_uchar (const unsigned char *str,
size_t len,
uint32_t *uc)
{
assert (str != NULL);
assert (len != 0);
assert (uc != NULL);
if (len < 4)
return -1;
*uc = ((uint32_t) str[0] << 24 | str[1] << 16 | str[2] << 8 | str[3]);
return 4;
}
bool
p11_utf8_validate (const char *str,
ssize_t len)
{
uint32_t dummy;
ssize_t ret;
if (len < 0)
len = strlen (str);
while (len > 0) {
ret = utf8_to_uchar (str, len, &dummy);
if (ret < 0)
return false;
str += ret;
len -= ret;
}
return true;
}
static char *
utf8_for_convert (ssize_t (* convert) (const unsigned char *, size_t, uint32_t *),
const unsigned char *str,
size_t num_bytes,
size_t *ret_len)
{
p11_buffer buf;
char block[6];
uint32_t uc;
ssize_t ret;
assert (convert);
if (!p11_buffer_init_null (&buf, num_bytes))
return_val_if_reached (NULL);
while (num_bytes != 0) {
ret = (convert) (str, num_bytes, &uc);
if (ret < 0) {
p11_buffer_uninit (&buf);
return NULL;
}
str += ret;
num_bytes -= ret;
ret = utf8_for_uchar (uc, block, 6);
if (ret < 0) {
p11_buffer_uninit (&buf);
return NULL;
}
p11_buffer_add (&buf, block, ret);
}
return_val_if_fail (p11_buffer_ok (&buf), NULL);
return p11_buffer_steal (&buf, ret_len);
}
char *
p11_utf8_for_ucs2be (const unsigned char *str,
size_t num_bytes,
size_t *ret_len)
{
assert (str != NULL);
return utf8_for_convert (ucs2be_to_uchar, str, num_bytes, ret_len);
}
char *
p11_utf8_for_ucs4be (const unsigned char *str,
size_t num_bytes,
size_t *ret_len)
{
assert (str != NULL);
return utf8_for_convert (ucs4be_to_uchar, str, num_bytes, ret_len);
}