gecko-dev/netwerk/dns/race.c

236 строки
5.7 KiB
C
Исходник Обычный вид История

/*
* Copyright (c) 2000,2001,2002 Japan Network Information Center.
* All rights reserved.
*
* By using this file, you agree to the terms and conditions set forth bellow.
*
* LICENSE TERMS AND CONDITIONS
*
* The following License Terms and Conditions apply, unless a different
* license is obtained from Japan Network Information Center ("JPNIC"),
* a Japanese association, Kokusai-Kougyou-Kanda Bldg 6F, 2-3-4 Uchi-Kanda,
* Chiyoda-ku, Tokyo 101-0047, Japan.
*
* 1. Use, Modification and Redistribution (including distribution of any
* modified or derived work) in source and/or binary forms is permitted
* under this License Terms and Conditions.
*
* 2. Redistribution of source code must retain the copyright notices as they
* appear in each source code file, this License Terms and Conditions.
*
* 3. Redistribution in binary form must reproduce the Copyright Notice,
* this License Terms and Conditions, in the documentation and/or other
* materials provided with the distribution. For the purposes of binary
* distribution the "Copyright Notice" refers to the following language:
* "Copyright (c) 2000-2002 Japan Network Information Center. All rights reserved."
*
* 4. The name of JPNIC may not be used to endorse or promote products
* derived from this Software without specific prior written approval of
* JPNIC.
*
* 5. Disclaimer/Limitation of Liability: THIS SOFTWARE IS PROVIDED BY JPNIC
* "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 JPNIC 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 DAMAGES.
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include "nsIDNKitInterface.h"
#define RACE_2OCTET_MODE 0xd8
#define RACE_ESCAPE 0xff
#define RACE_ESCAPE_2ND 0x99
/*
* Compression type.
*/
enum {
compress_one, /* all characters are in a single row */
compress_two, /* row 0 and another row */
compress_none /* nope */
};
idn_result_t
race_decode_decompress(const char *from, uint16_t *buf, size_t buflen)
{
uint16_t *p = buf;
unsigned int bitbuf = 0;
int bitlen = 0;
unsigned int i, j;
size_t len;
while (*from != '\0') {
int c = *from++;
int x;
if ('a' <= c && c <= 'z')
x = c - 'a';
else if ('A' <= c && c <= 'Z')
x = c - 'A';
else if ('2' <= c && c <= '7')
x = c - '2' + 26;
else
return (idn_invalid_encoding);
bitbuf = (bitbuf << 5) + x;
bitlen += 5;
if (bitlen >= 8) {
*p++ = (bitbuf >> (bitlen - 8)) & 0xff;
bitlen -= 8;
}
}
len = p - buf;
/*
* Now 'buf' holds the decoded string.
*/
/*
* Decompress.
*/
if (buf[0] == RACE_2OCTET_MODE) {
if ((len - 1) % 2 != 0)
return (idn_invalid_encoding);
for (i = 1, j = 0; i < len; i += 2, j++)
buf[j] = (buf[i] << 8) + buf[i + 1];
len = j;
} else {
uint16_t c = buf[0] << 8; /* higher octet */
for (i = 1, j = 0; i < len; j++) {
if (buf[i] == RACE_ESCAPE) {
if (i + 1 >= len)
return (idn_invalid_encoding);
else if (buf[i + 1] == RACE_ESCAPE_2ND)
buf[j] = c | 0xff;
else
buf[j] = buf[i + 1];
i += 2;
} else if (buf[i] == 0x99 && c == 0x00) {
/*
* The RACE specification says this is error.
*/
return (idn_invalid_encoding);
} else {
buf[j] = c | buf[i++];
}
}
len = j;
}
buf[len] = '\0';
return (idn_success);
}
idn_result_t
race_compress_encode(const uint16_t *p, int compress_mode,
char *to, size_t tolen)
{
uint32_t bitbuf = *p++; /* bit stream buffer */
int bitlen = 8; /* # of bits in 'bitbuf' */
while (*p != '\0' || bitlen > 0) {
unsigned int c = *p;
if (c == '\0') {
/* End of data. Flush. */
bitbuf <<= (5 - bitlen);
bitlen = 5;
} else if (compress_mode == compress_none) {
/* Push 16 bit data. */
bitbuf = (bitbuf << 16) | c;
bitlen += 16;
p++;
} else {/* compress_mode == compress_one/compress_two */
/* Push 8 or 16 bit data. */
if (compress_mode == compress_two &&
(c & 0xff00) == 0) {
/* Upper octet is zero (and not U1). */
bitbuf = (bitbuf << 16) | 0xff00 | c;
bitlen += 16;
} else if ((c & 0xff) == 0xff) {
/* Lower octet is 0xff. */
bitbuf = (bitbuf << 16) |
(RACE_ESCAPE << 8) | RACE_ESCAPE_2ND;
bitlen += 16;
} else {
/* Just output lower octet. */
bitbuf = (bitbuf << 8) | (c & 0xff);
bitlen += 8;
}
p++;
}
/*
* Output bits in 'bitbuf' in 5-bit unit.
*/
while (bitlen >= 5) {
int x;
/* Get top 5 bits. */
x = (bitbuf >> (bitlen - 5)) & 0x1f;
bitlen -= 5;
/* Encode. */
if (x < 26)
x += 'a';
else
x = (x - 26) + '2';
if (tolen < 1)
return (idn_buffer_overflow);
*to++ = x;
tolen--;
}
}
if (tolen <= 0)
return (idn_buffer_overflow);
*to = '\0';
return (idn_success);
}
int
get_compress_mode(uint16_t *p) {
int zero = 0;
unsigned int upper = 0;
uint16_t *modepos = p - 1;
while (*p != '\0') {
unsigned int hi = *p++ & 0xff00;
if (hi == 0) {
zero++;
} else if (hi == upper) {
;
} else if (upper == 0) {
upper = hi;
} else {
*modepos = RACE_2OCTET_MODE;
return (compress_none);
}
}
*modepos = upper >> 8;
if (upper > 0 && zero > 0)
return (compress_two);
else
return (compress_one);
}