/* * Cryptographic API. * * Function for checking keys for the DES and Tripple DES Encryption * algorithms. * * Originally released as descore by Dana L. How <how@isl.stanford.edu>. * Modified by Raimar Falke <rf13@inf.tu-dresden.de> for the Linux-Kernel. * Derived from Cryptoapi and Nettle implementations, adapted for in-place * scatterlist interface.  Changed LGPL to GPL per section 3 of the LGPL. * * s390 Version: *   Copyright (C) 2003 IBM Deutschland GmbH, IBM Corporation *   Author(s): Thomas Spatzier (tspat@de.ibm.com) * * Derived from "crypto/des.c" *   Copyright (c) 1992 Dana L. How. *   Copyright (c) Raimar Falke <rf13@inf.tu-dresden.de> *   Copyright (c) Gisle Sflensminde <gisle@ii.uib.no> *   Copyright (C) 2001 Niels Mvller. *   Copyright (c) 2002 James Morris <jmorris@intercode.com.au> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * */#include <linux/init.h>#include <linux/module.h>#include <linux/errno.h>#include <linux/crypto.h>#define ROR(d,c,o)	((d) = (d) >> (c) | (d) << (o))static const u8 parity[] = {	8,1,0,8,0,8,8,0,0,8,8,0,8,0,2,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,3,	0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,	0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,	8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,	0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,	8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,	8,0,0,8,0,8,8,0,0,8,8,0,8,0,0,8,0,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,	4,8,8,0,8,0,0,8,8,0,0,8,0,8,8,0,8,5,0,8,0,8,8,0,0,8,8,0,8,0,6,8,};/* * RFC2451: Weak key checks SHOULD be performed. */intcrypto_des_check_key(const u8 *key, unsigned int keylen, u32 *flags){	u32 n, w;	n  = parity[key[0]]; n <<= 4;	n |= parity[key[1]]; n <<= 4;	n |= parity[key[2]]; n <<= 4;	n |= parity[key[3]]; n <<= 4;	n |= parity[key[4]]; n <<= 4;	n |= parity[key[5]]; n <<= 4;	n |= parity[key[6]]; n <<= 4;	n |= parity[key[7]];	w = 0x88888888L;	if ((*flags & CRYPTO_TFM_REQ_WEAK_KEY)	    && !((n - (w >> 3)) & w)) {  /* 1 in 10^10 keys passes this test */		if (n < 0x41415151) {			if (n < 0x31312121) {				if (n < 0x14141515) {					/* 01 01 01 01 01 01 01 01 */					if (n == 0x11111111) goto weak;					/* 01 1F 01 1F 01 0E 01 0E */					if (n == 0x13131212) goto weak;				} else {					/* 01 E0 01 E0 01 F1 01 F1 */					if (n == 0x14141515) goto weak;					/* 01 FE 01 FE 01 FE 01 FE */					if (n == 0x16161616) goto weak;				}			} else {				if (n < 0x34342525) {					/* 1F 01 1F 01 0E 01 0E 01 */					if (n == 0x31312121) goto weak;					/* 1F 1F 1F 1F 0E 0E 0E 0E (?) */					if (n == 0x33332222) goto weak;				} else {					/* 1F E0 1F E0 0E F1 0E F1 */					if (n == 0x34342525) goto weak;					/* 1F FE 1F FE 0E FE 0E FE */					if (n == 0x36362626) goto weak;				}			}		} else {			if (n < 0x61616161) {				if (n < 0x44445555) {					/* E0 01 E0 01 F1 01 F1 01 */					if (n == 0x41415151) goto weak;					/* E0 1F E0 1F F1 0E F1 0E */					if (n == 0x43435252) goto weak;				} else {					/* E0 E0 E0 E0 F1 F1 F1 F1 (?) */					if (n == 0x44445555) goto weak;					/* E0 FE E0 FE F1 FE F1 FE */					if (n == 0x46465656) goto weak;				}			} else {				if (n < 0x64646565) {					/* FE 01 FE 01 FE 01 FE 01 */					if (n == 0x61616161) goto weak;					/* FE 1F FE 1F FE 0E FE 0E */					if (n == 0x63636262) goto weak;				} else {					/* FE E0 FE E0 FE F1 FE F1 */					if (n == 0x64646565) goto weak;					/* FE FE FE FE FE FE FE FE */					if (n == 0x66666666) goto weak;				}			}		}	}	return 0;weak:	*flags |= CRYPTO_TFM_RES_WEAK_KEY;	return -EINVAL;}EXPORT_SYMBOL(crypto_des_check_key);MODULE_LICENSE("GPL");MODULE_DESCRIPTION("Key Check function for DES &  DES3 Cipher Algorithms");