freebsd-skq/lib/libcrypt/crypt-nthash.c
ed b7ac6522e5 Make libcrypt thread-safe. Add crypt_r(3).
glibc has a pretty nice function called crypt_r(3), which is nothing
more than crypt(3), but thread-safe. It accomplishes this by introducing
a 'struct crypt_data' structure that contains a buffer that is large
enough to hold the resulting string.

Let's go ahead and also add this function. It would be a shame if a
useful function like this wouldn't be usable in multithreaded apps.
Refactor crypt.c and all of the backends to no longer declare static
arrays, but write their output in a provided buffer.

There is no need to do any buffer length computation here, as we'll just
need to ensure that 'struct crypt_data' is large enough, which it is.
_PASSWORD_LEN is defined to 128 bytes, but in this case I'm picking 256,
as this is going to be part of the actual ABI.

Differential Revision:	https://reviews.freebsd.org/D7306
2016-08-10 15:16:28 +00:00

82 lines
2.4 KiB
C

/*-
* Copyright (c) 2003 Michael Bretterklieber
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <netinet/in.h>
#include <ctype.h>
#include <err.h>
#include <md4.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "crypt.h"
/*
* NT HASH = md4(str2unicode(pw))
*/
/* ARGSUSED */
int
crypt_nthash(const char *pw, const char *salt __unused, char *buffer)
{
size_t unipwLen;
int i;
static const char hexconvtab[] = "0123456789abcdef";
static const char *magic = "$3$";
u_int16_t unipw[128];
u_char hash[MD4_SIZE];
const char *s;
MD4_CTX ctx;
bzero(unipw, sizeof(unipw));
/* convert to unicode (thanx Archie) */
unipwLen = 0;
for (s = pw; unipwLen < sizeof(unipw) / 2 && *s; s++)
unipw[unipwLen++] = htons(*s << 8);
/* Compute MD4 of Unicode password */
MD4Init(&ctx);
MD4Update(&ctx, (u_char *)unipw, unipwLen*sizeof(u_int16_t));
MD4Final(hash, &ctx);
buffer = stpcpy(buffer, magic);
*buffer++ = '$';
for (i = 0; i < MD4_SIZE; i++) {
*buffer++ = hexconvtab[hash[i] >> 4];
*buffer++ = hexconvtab[hash[i] & 15];
}
*buffer = '\0';
return (0);
}