glibc/crypt/crypt-entry.c

193 lines
5.3 KiB
C

/*
* UFC-crypt: ultra fast crypt(3) implementation
*
* Copyright (C) 1991-2017 Free Software Foundation, Inc.
*
* The GNU C Library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* The GNU C Library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with the GNU C Library; if not, see
* <http://www.gnu.org/licenses/>.
*
* crypt entry points
*
* @(#)crypt-entry.c 1.2 12/20/96
*
*/
#ifdef DEBUG
#include <stdio.h>
#endif
#include <string.h>
#include <errno.h>
#include <fips-private.h>
#ifndef STATIC
#define STATIC static
#endif
#include "crypt-private.h"
/* Prototypes for local functions. */
#ifndef __GNU_LIBRARY__
void _ufc_clearmem (char *start, int cnt);
#else
#define _ufc_clearmem(start, cnt) memset(start, 0, cnt)
#endif
extern char *__md5_crypt_r (const char *key, const char *salt, char *buffer,
int buflen);
extern char *__md5_crypt (const char *key, const char *salt);
extern char *__sha256_crypt_r (const char *key, const char *salt,
char *buffer, int buflen);
extern char *__sha256_crypt (const char *key, const char *salt);
extern char *__sha512_crypt_r (const char *key, const char *salt,
char *buffer, int buflen);
extern char *__sha512_crypt (const char *key, const char *salt);
/* Define our magic string to mark salt for MD5 encryption
replacement. This is meant to be the same as for other MD5 based
encryption implementations. */
static const char md5_salt_prefix[] = "$1$";
/* Magic string for SHA256 encryption. */
static const char sha256_salt_prefix[] = "$5$";
/* Magic string for SHA512 encryption. */
static const char sha512_salt_prefix[] = "$6$";
/* For use by the old, non-reentrant routines (crypt/encrypt/setkey) */
extern struct crypt_data _ufc_foobar;
/*
* UNIX crypt function
*/
char *
__crypt_r (const char *key, const char *salt,
struct crypt_data * __restrict data)
{
ufc_long res[4];
char ktab[9];
ufc_long xx = 25; /* to cope with GCC long long compiler bugs */
#ifdef _LIBC
/* Try to find out whether we have to use MD5 encryption replacement. */
if (strncmp (md5_salt_prefix, salt, sizeof (md5_salt_prefix) - 1) == 0)
{
/* FIPS rules out MD5 password encryption. */
if (fips_enabled_p ())
{
__set_errno (EPERM);
return NULL;
}
return __md5_crypt_r (key, salt, (char *) data,
sizeof (struct crypt_data));
}
/* Try to find out whether we have to use SHA256 encryption replacement. */
if (strncmp (sha256_salt_prefix, salt, sizeof (sha256_salt_prefix) - 1) == 0)
return __sha256_crypt_r (key, salt, (char *) data,
sizeof (struct crypt_data));
/* Try to find out whether we have to use SHA512 encryption replacement. */
if (strncmp (sha512_salt_prefix, salt, sizeof (sha512_salt_prefix) - 1) == 0)
return __sha512_crypt_r (key, salt, (char *) data,
sizeof (struct crypt_data));
#endif
/*
* Hack DES tables according to salt
*/
if (!_ufc_setup_salt_r (salt, data))
{
__set_errno (EINVAL);
return NULL;
}
/* FIPS rules out DES password encryption. */
if (fips_enabled_p ())
{
__set_errno (EPERM);
return NULL;
}
/*
* Setup key schedule
*/
_ufc_clearmem (ktab, (int) sizeof (ktab));
(void) strncpy (ktab, key, 8);
_ufc_mk_keytab_r (ktab, data);
/*
* Go for the 25 DES encryptions
*/
_ufc_clearmem ((char*) res, (int) sizeof (res));
_ufc_doit_r (xx, data, &res[0]);
/*
* Do final permutations
*/
_ufc_dofinalperm_r (res, data);
/*
* And convert back to 6 bit ASCII
*/
_ufc_output_conversion_r (res[0], res[1], salt, data);
/*
* Erase key-dependent intermediate data. Data dependent only on
* the salt is not considered sensitive.
*/
explicit_bzero (ktab, sizeof (ktab));
explicit_bzero (data->keysched, sizeof (data->keysched));
explicit_bzero (res, sizeof (res));
return data->crypt_3_buf;
}
weak_alias (__crypt_r, crypt_r)
char *
crypt (const char *key, const char *salt)
{
#ifdef _LIBC
/* Try to find out whether we have to use MD5 encryption replacement. */
if (strncmp (md5_salt_prefix, salt, sizeof (md5_salt_prefix) - 1) == 0
/* Let __crypt_r deal with the error code if FIPS is enabled. */
&& !fips_enabled_p ())
return __md5_crypt (key, salt);
/* Try to find out whether we have to use SHA256 encryption replacement. */
if (strncmp (sha256_salt_prefix, salt, sizeof (sha256_salt_prefix) - 1) == 0)
return __sha256_crypt (key, salt);
/* Try to find out whether we have to use SHA512 encryption replacement. */
if (strncmp (sha512_salt_prefix, salt, sizeof (sha512_salt_prefix) - 1) == 0)
return __sha512_crypt (key, salt);
#endif
return __crypt_r (key, salt, &_ufc_foobar);
}
/*
* To make fcrypt users happy.
* They don't need to call init_des.
*/
#ifdef _LIBC
weak_alias (crypt, fcrypt)
#else
char *
__fcrypt (const char *key, const char *salt)
{
return crypt (key, salt);
}
#endif