michael@0: /*
michael@0:  * Copyright (c) 2000,2001,2002 Japan Network Information Center.
michael@0:  * All rights reserved.
michael@0:  *  
michael@0:  * By using this file, you agree to the terms and conditions set forth bellow.
michael@0:  * 
michael@0:  * 			LICENSE TERMS AND CONDITIONS 
michael@0:  * 
michael@0:  * The following License Terms and Conditions apply, unless a different
michael@0:  * license is obtained from Japan Network Information Center ("JPNIC"),
michael@0:  * a Japanese association, Kokusai-Kougyou-Kanda Bldg 6F, 2-3-4 Uchi-Kanda,
michael@0:  * Chiyoda-ku, Tokyo 101-0047, Japan.
michael@0:  * 
michael@0:  * 1. Use, Modification and Redistribution (including distribution of any
michael@0:  *    modified or derived work) in source and/or binary forms is permitted
michael@0:  *    under this License Terms and Conditions.
michael@0:  * 
michael@0:  * 2. Redistribution of source code must retain the copyright notices as they
michael@0:  *    appear in each source code file, this License Terms and Conditions.
michael@0:  * 
michael@0:  * 3. Redistribution in binary form must reproduce the Copyright Notice,
michael@0:  *    this License Terms and Conditions, in the documentation and/or other
michael@0:  *    materials provided with the distribution.  For the purposes of binary
michael@0:  *    distribution the "Copyright Notice" refers to the following language:
michael@0:  *    "Copyright (c) 2000-2002 Japan Network Information Center.  All rights reserved."
michael@0:  * 
michael@0:  * 4. The name of JPNIC may not be used to endorse or promote products
michael@0:  *    derived from this Software without specific prior written approval of
michael@0:  *    JPNIC.
michael@0:  * 
michael@0:  * 5. Disclaimer/Limitation of Liability: THIS SOFTWARE IS PROVIDED BY JPNIC
michael@0:  *    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  *    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
michael@0:  *    PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL JPNIC BE LIABLE
michael@0:  *    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
michael@0:  *    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
michael@0:  *    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
michael@0:  *    BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
michael@0:  *    WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
michael@0:  *    OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
michael@0:  *    ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include <stddef.h>
michael@0: #include <stdlib.h>
michael@0: #include <string.h>
michael@0: 
michael@0: #include "nsIDNKitInterface.h"
michael@0: 
michael@0: 
michael@0: #define RACE_2OCTET_MODE	0xd8
michael@0: #define RACE_ESCAPE		0xff
michael@0: #define RACE_ESCAPE_2ND		0x99
michael@0: 
michael@0: /*
michael@0:  * Compression type.
michael@0:  */
michael@0: enum {
michael@0: 	compress_one,	/* all characters are in a single row */
michael@0: 	compress_two,	/* row 0 and another row */
michael@0: 	compress_none	/* nope */
michael@0: };
michael@0: 
michael@0: 
michael@0: idn_result_t
michael@0: race_decode_decompress(const char *from, uint16_t *buf, size_t buflen)
michael@0: {
michael@0: 	uint16_t *p = buf;
michael@0: 	unsigned int bitbuf = 0;
michael@0: 	int bitlen = 0;
michael@0: 	unsigned int i, j;
michael@0: 	size_t len;
michael@0: 
michael@0: 	while (*from != '\0') {
michael@0: 		int c = *from++;
michael@0: 		int x;
michael@0: 
michael@0: 		if ('a' <= c && c <= 'z')
michael@0: 			x = c - 'a';
michael@0: 		else if ('A' <= c && c <= 'Z')
michael@0: 			x = c - 'A';
michael@0: 		else if ('2' <= c && c <= '7')
michael@0: 			x = c - '2' + 26;
michael@0: 		else
michael@0: 			return (idn_invalid_encoding);
michael@0: 
michael@0: 		bitbuf = (bitbuf << 5) + x;
michael@0: 		bitlen += 5;
michael@0: 		if (bitlen >= 8) {
michael@0: 			*p++ = (bitbuf >> (bitlen - 8)) & 0xff;
michael@0: 			bitlen -= 8;
michael@0: 		}
michael@0: 	}
michael@0: 	len = p - buf;
michael@0: 
michael@0: 	/*
michael@0: 	 * Now 'buf' holds the decoded string.
michael@0: 	 */
michael@0: 
michael@0: 	/*
michael@0: 	 * Decompress.
michael@0: 	 */
michael@0: 	if (buf[0] == RACE_2OCTET_MODE) {
michael@0: 		if ((len - 1) % 2 != 0)
michael@0: 			return (idn_invalid_encoding);
michael@0: 		for (i = 1, j = 0; i < len; i += 2, j++)
michael@0: 			buf[j] = (buf[i] << 8) + buf[i + 1];
michael@0: 		len = j;
michael@0: 	} else {
michael@0: 		uint16_t c = buf[0] << 8;	/* higher octet */
michael@0: 
michael@0: 		for (i = 1, j = 0; i < len; j++) {
michael@0: 			if (buf[i] == RACE_ESCAPE) {
michael@0: 				if (i + 1 >= len)
michael@0: 					return (idn_invalid_encoding);
michael@0: 				else if (buf[i + 1] == RACE_ESCAPE_2ND)
michael@0: 					buf[j] = c | 0xff;
michael@0: 				else
michael@0: 					buf[j] = buf[i + 1];
michael@0: 				i += 2;
michael@0: 
michael@0: 			} else if (buf[i] == 0x99 && c == 0x00) {
michael@0: 				/*
michael@0: 				 * The RACE specification says this is error.
michael@0: 				 */
michael@0: 				return (idn_invalid_encoding);
michael@0: 				 
michael@0: 			} else {
michael@0: 				buf[j] = c | buf[i++];
michael@0: 			}
michael@0: 		}
michael@0: 		len = j;
michael@0: 	}
michael@0: 	buf[len] = '\0';
michael@0: 
michael@0: 	return (idn_success);
michael@0: }
michael@0: 
michael@0: idn_result_t
michael@0: race_compress_encode(const uint16_t *p, int compress_mode,
michael@0: 		     char *to, size_t tolen)
michael@0: {
michael@0: 	uint32_t bitbuf = *p++;	/* bit stream buffer */
michael@0: 	int bitlen = 8;			/* # of bits in 'bitbuf' */
michael@0: 
michael@0: 	while (*p != '\0' || bitlen > 0) {
michael@0: 		unsigned int c = *p;
michael@0: 
michael@0: 		if (c == '\0') {
michael@0: 			/* End of data.  Flush. */
michael@0: 			bitbuf <<= (5 - bitlen);
michael@0: 			bitlen = 5;
michael@0: 		} else if (compress_mode == compress_none) {
michael@0: 			/* Push 16 bit data. */
michael@0: 			bitbuf = (bitbuf << 16) | c;
michael@0: 			bitlen += 16;
michael@0: 			p++;
michael@0: 		} else {/* compress_mode == compress_one/compress_two */
michael@0: 			/* Push 8 or 16 bit data. */
michael@0: 			if (compress_mode == compress_two &&
michael@0: 			    (c & 0xff00) == 0) {
michael@0: 				/* Upper octet is zero (and not U1). */
michael@0: 				bitbuf = (bitbuf << 16) | 0xff00 | c;
michael@0: 				bitlen += 16;
michael@0: 			} else if ((c & 0xff) == 0xff) {
michael@0: 				/* Lower octet is 0xff. */
michael@0: 				bitbuf = (bitbuf << 16) |
michael@0: 					(RACE_ESCAPE << 8) | RACE_ESCAPE_2ND;
michael@0: 				bitlen += 16;
michael@0: 			} else {
michael@0: 				/* Just output lower octet. */
michael@0: 				bitbuf = (bitbuf << 8) | (c & 0xff);
michael@0: 				bitlen += 8;
michael@0: 			}
michael@0: 			p++;
michael@0: 		}
michael@0: 
michael@0: 		/*
michael@0: 		 * Output bits in 'bitbuf' in 5-bit unit.
michael@0: 		 */
michael@0: 		while (bitlen >= 5) {
michael@0: 			int x;
michael@0: 
michael@0: 			/* Get top 5 bits. */
michael@0: 			x = (bitbuf >> (bitlen - 5)) & 0x1f;
michael@0: 			bitlen -= 5;
michael@0: 
michael@0: 			/* Encode. */
michael@0: 			if (x < 26)
michael@0: 				x += 'a';
michael@0: 			else
michael@0: 				x = (x - 26) + '2';
michael@0: 
michael@0: 			if (tolen < 1)
michael@0: 				return (idn_buffer_overflow);
michael@0: 
michael@0: 			*to++ = x;
michael@0: 			tolen--;
michael@0: 		}
michael@0: 	}
michael@0: 
michael@0: 	if (tolen <= 0)
michael@0: 		return (idn_buffer_overflow);
michael@0: 
michael@0: 	*to = '\0';
michael@0: 	return (idn_success);
michael@0: }
michael@0: 
michael@0: int
michael@0: get_compress_mode(uint16_t *p) {
michael@0: 	int zero = 0;
michael@0: 	unsigned int upper = 0;
michael@0: 	uint16_t *modepos = p - 1;
michael@0: 
michael@0: 	while (*p != '\0') {
michael@0: 		unsigned int hi = *p++ & 0xff00;
michael@0: 
michael@0: 		if (hi == 0) {
michael@0: 			zero++;
michael@0: 		} else if (hi == upper) {
michael@0: 			;
michael@0: 		} else if (upper == 0) {
michael@0: 			upper = hi;
michael@0: 		} else {
michael@0: 			*modepos = RACE_2OCTET_MODE;
michael@0: 			return (compress_none);
michael@0: 		}
michael@0: 	}
michael@0: 	*modepos = upper >> 8;
michael@0: 	if (upper > 0 && zero > 0)
michael@0: 		return (compress_two);
michael@0: 	else
michael@0: 		return (compress_one);
michael@0: }