342 lines
8.9 KiB
C
342 lines
8.9 KiB
C
#ifndef lint
|
|
static char *rcsid = "$Id: dn.c,v 1.8 2000/09/20 02:47:31 ishisone Exp $";
|
|
#endif
|
|
|
|
/*
|
|
* Copyright (c) 2000 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, Fuundo Bldg., 1-2 Kanda Ogawamachi, Chiyoda-ku,
|
|
* Tokyo, 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) Japan Network Information Center. All rights reserved."
|
|
*
|
|
* 4. Neither the name of JPNIC may 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.
|
|
*
|
|
* 6. Indemnification by Licensee
|
|
* Any person or entities using and/or redistributing this Software under
|
|
* this License Terms and Conditions shall defend indemnify and hold
|
|
* harmless JPNIC from and against any and all judgements damages,
|
|
* expenses, settlement liabilities, cost and other liabilities of any
|
|
* kind as a result of use and redistribution of this Software or any
|
|
* claim, suite, action, litigation or proceeding by any third party
|
|
* arising out of or relates to this License Terms and Conditions.
|
|
*
|
|
* 7. Governing Law, Jurisdiction and Venue
|
|
* This License Terms and Conditions shall be governed by and and
|
|
* construed in accordance with the law of Japan. Any person or entities
|
|
* using and/or redistributing this Software under this License Terms and
|
|
* Conditions hereby agrees and consent to the personal and exclusive
|
|
* jurisdiction and venue of Tokyo District Court of Japan.
|
|
*/
|
|
|
|
/*
|
|
* Domain name compression/expansion.
|
|
*
|
|
* Similar to the functionality of dn_comp/dn_expand in the resolv library.
|
|
* In fact, the loop detection in mdn__dn_expand is borrowed from
|
|
* ns_name_unpack.
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#include <stddef.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include <mdn/result.h>
|
|
#include <mdn/assert.h>
|
|
#include <mdn/logmacro.h>
|
|
#include <mdn/dn.h>
|
|
|
|
#define COMPRESS_MASK 0xc0
|
|
#define COMPRESS_FLAG 0xc0
|
|
#define MAX_OFFSET 0x3fff
|
|
|
|
#define MAXNAMELEN 1024
|
|
#define MAXLABEL 63
|
|
#define MAXCOMPRESS 255
|
|
|
|
/*
|
|
* uppercase -> lowercase conversion table, to be initialized
|
|
* by init_lcase().
|
|
*/
|
|
static char lcase[128];
|
|
|
|
static mdn_result_t split_name(const char *name, unsigned char *namebuf);
|
|
static int find_label(const unsigned char *p, int limit,
|
|
mdn__dn_t *ctx);
|
|
static int match(const unsigned char *p, const unsigned char *q,
|
|
mdn__dn_t *ctx);
|
|
static void append_ptr(mdn__dn_t *ctx, unsigned char *ptr);
|
|
static int get_offset(const unsigned char *p);
|
|
static void init_lcase(void);
|
|
|
|
|
|
mdn_result_t
|
|
mdn__dn_expand(const char *msg, size_t msglen, const char *compressed,
|
|
char *expanded, size_t buflen, size_t *complenp)
|
|
{
|
|
const unsigned char *p = (const unsigned char *)compressed;
|
|
const unsigned char *ueom = (const unsigned char *)(msg + msglen);
|
|
int compress_len = 0;
|
|
size_t checked = 0;
|
|
|
|
assert(msg != NULL && expanded != NULL && complenp != NULL);
|
|
|
|
/*
|
|
* Sanity check.
|
|
*/
|
|
if (compressed < msg || msg + msglen <= compressed)
|
|
return (mdn_invalid_message);
|
|
|
|
if (*p == 0) {
|
|
/* Root label */
|
|
if (buflen < 2)
|
|
return (mdn_buffer_overflow);
|
|
(void)strcpy(expanded, ".");
|
|
*complenp = 1;
|
|
return (mdn_success);
|
|
}
|
|
|
|
while (p < ueom) {
|
|
int c = *p++;
|
|
size_t len;
|
|
|
|
len = c & ~COMPRESS_MASK;
|
|
|
|
if (c == 0) {
|
|
if (compress_len == 0)
|
|
compress_len = (const char *)p - compressed;
|
|
*complenp = compress_len;
|
|
return (mdn_success);
|
|
} else if ((c & COMPRESS_MASK) == 0) {
|
|
if (p + len > ueom)
|
|
return (mdn_invalid_message);
|
|
if (buflen < len + 2)
|
|
return (mdn_buffer_overflow);
|
|
(void)memcpy(expanded, p, len);
|
|
(void)strcpy(expanded + len, "."); /* dot and NUL */
|
|
p += len;
|
|
checked += len + 1;
|
|
expanded += len + 1;
|
|
buflen -= len + 1;
|
|
} else if ((c & COMPRESS_MASK) == COMPRESS_FLAG) {
|
|
if (p >= ueom)
|
|
return (mdn_invalid_message);
|
|
len = (len << 8) + *p++;
|
|
if (compress_len == 0)
|
|
compress_len = (const char *)p - compressed;
|
|
p = (const unsigned char *)(msg + len);
|
|
|
|
/*
|
|
* Loop detection.
|
|
*/
|
|
checked += 2;
|
|
if (checked >= msglen) {
|
|
WARNING(("mdn__dn_expand: loop detected\n"));
|
|
return (mdn_invalid_message);
|
|
}
|
|
} else {
|
|
return (mdn_invalid_message);
|
|
}
|
|
}
|
|
return (mdn_invalid_message);
|
|
}
|
|
|
|
void
|
|
mdn__dn_initcompress(mdn__dn_t *ctx, const char *msg) {
|
|
ctx->msg = (const unsigned char *)msg;
|
|
ctx->cur = 0;
|
|
}
|
|
|
|
mdn_result_t
|
|
mdn__dn_compress(const char *name, char *sptr, size_t length,
|
|
mdn__dn_t *ctx, size_t *complenp)
|
|
{
|
|
unsigned char namebuf[MAXNAMELEN+1];
|
|
unsigned char *ptr, *p;
|
|
mdn_result_t r;
|
|
int offset_limit;
|
|
static int initialized = 0;
|
|
|
|
if (!initialized) {
|
|
init_lcase();
|
|
initialized = 1;
|
|
}
|
|
|
|
/*
|
|
* Split domain name into labels.
|
|
*/
|
|
if ((r = split_name(name, namebuf)) != mdn_success)
|
|
return (r);
|
|
|
|
p = namebuf;
|
|
ptr = (unsigned char *)sptr;
|
|
offset_limit = ctx->cur;
|
|
while (*p != 0) {
|
|
int off;
|
|
|
|
if ((off = find_label(p, offset_limit, ctx)) >= 0) {
|
|
if (length < 2)
|
|
return (mdn_buffer_overflow);
|
|
|
|
ptr[0] = COMPRESS_FLAG | (off >> 8);
|
|
ptr[1] = off & 0xff;
|
|
ptr += 2;
|
|
if ((*complenp = (char *)ptr - sptr) > MAXCOMPRESS)
|
|
return (mdn_invalid_name);
|
|
return (mdn_success);
|
|
} else {
|
|
int l = *p + 1;
|
|
|
|
if (length < l)
|
|
return (mdn_buffer_overflow);
|
|
|
|
(void)memcpy(ptr, p, l);
|
|
append_ptr(ctx, ptr);
|
|
|
|
ptr += l;
|
|
length -= l;
|
|
}
|
|
p += *p + 1;
|
|
}
|
|
if (length < 1)
|
|
return (mdn_buffer_overflow);
|
|
*ptr++ = 0;
|
|
if ((*complenp = (char *)ptr - sptr) > MAXCOMPRESS)
|
|
return (mdn_invalid_name);
|
|
return (mdn_success);
|
|
}
|
|
|
|
static mdn_result_t
|
|
split_name(const char *name, unsigned char *namebuf) {
|
|
const unsigned char *p = (const unsigned char *)name;
|
|
const unsigned char *end = p + MAXNAMELEN;
|
|
unsigned char *q, *qtop;
|
|
|
|
q = namebuf;
|
|
qtop = q++;
|
|
while (p < end) {
|
|
if (*p == '.' || *p == '\0') {
|
|
int len = q - qtop - 1;
|
|
if (len > MAXLABEL)
|
|
return (mdn_invalid_name);
|
|
*qtop = len;
|
|
qtop = q++;
|
|
if (*p == '\0') {
|
|
*qtop = 0;
|
|
return (mdn_success);
|
|
}
|
|
p++;
|
|
} else {
|
|
*q++ = *p++;
|
|
}
|
|
}
|
|
/* Name too long. */
|
|
return (mdn_invalid_name);
|
|
}
|
|
|
|
static int
|
|
find_label(const unsigned char *p, int limit, mdn__dn_t *ctx) {
|
|
int i;
|
|
|
|
assert(limit <= ctx->cur);
|
|
|
|
if (ctx == NULL)
|
|
return (-1);
|
|
|
|
for (i = 0; i < limit; i++) {
|
|
if (match(p, ctx->msg + ctx->offset[i], ctx))
|
|
return (ctx->offset[i]);
|
|
}
|
|
return (-1);
|
|
}
|
|
|
|
static int
|
|
match(const unsigned char *p, const unsigned char *q, mdn__dn_t *ctx) {
|
|
for (;;) {
|
|
int len, l;
|
|
|
|
/* Dereference 'q'. */
|
|
while ((*q & COMPRESS_FLAG) != 0) {
|
|
int offset = get_offset(q);
|
|
|
|
if (offset < 0 || offset > MAX_OFFSET)
|
|
return (0);
|
|
q = ctx->msg + offset;
|
|
}
|
|
|
|
/* Check length. */
|
|
len = *p++;
|
|
if (*q++ != len)
|
|
return (0);
|
|
|
|
if (len == 0)
|
|
return (1);
|
|
|
|
/* Compare labels. */
|
|
for (l = 0; l < len; l++, p++, q++) {
|
|
if (*p == *q)
|
|
continue;
|
|
else if (*p < 128 && *q < 128 &&
|
|
lcase[*p] == lcase[*q])
|
|
continue;
|
|
else
|
|
return (0);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
append_ptr(mdn__dn_t *ctx, unsigned char *ptr) {
|
|
if (ctx != NULL && ctx->cur < MDN_DN_NPTRS &&
|
|
ptr >= ctx->msg && (ptr - ctx->msg) <= MAX_OFFSET)
|
|
ctx->offset[ctx->cur++] = ptr - ctx->msg;
|
|
}
|
|
|
|
static int
|
|
get_offset(const unsigned char *p) {
|
|
return (((p[0] & ~COMPRESS_MASK) << 8) | p[1]);
|
|
}
|
|
|
|
static void
|
|
init_lcase(void) {
|
|
int i;
|
|
|
|
for (i = 0; i < 128; i++)
|
|
lcase[i] = i;
|
|
for (i = 'A'; i <= 'Z'; i++)
|
|
lcase[i] += 'a' - 'A';
|
|
}
|