2011-01-28 16:07:46 -08:00

170 lines
4.1 KiB
C

// Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
//
// This file is part of the VNC system.
//
// The VNC system 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.
//
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
//
// If the source code for the VNC system is not available from the place whence
// you received this file, check http://www.uk.research.att.com/vnc or contact
// the authors on vnc@uk.research.att.com for information on obtaining it.
/*
* vncauth.c - Functions for VNC password management and authentication.
*/
/*
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
*/
#include "stdhdrs.h"
#include "vncauth.h"
#include "d3des.h"
/*
* We use a fixed key to store passwords, since we assume that our local
* file system is secure but nonetheless don't want to store passwords
* as plaintext.
*/
unsigned char fixedkey[8] = {23,82,107,6,35,78,88,7};
/*
* Encrypt CHALLENGESIZE bytes in memory using a password.
*/
void
vncEncryptBytes(unsigned char *bytes, char *passwd)
{
unsigned char key[8];
unsigned int i;
/* key is simply password padded with nulls */
for (i = 0; i < 8; i++) {
if (i < strlen(passwd)) {
key[i] = passwd[i];
} else {
key[i] = 0;
}
}
deskey(key, EN0);
for (i = 0; i < CHALLENGESIZE; i += 8) {
des(bytes+i, bytes+i);
}
}
/*
* Encrypt a password into the specified space.
* encryptedPasswd will be 8 bytes long - sufficient space
* should be allocated.
*/
void
vncEncryptPasswd( unsigned char *encryptedPasswd, char *passwd )
{
unsigned int i;
/* pad password with nulls */
for (i = 0; i < MAXPWLEN; i++) {
if (i < strlen(passwd)) {
encryptedPasswd[i] = passwd[i];
} else {
encryptedPasswd[i] = 0;
}
}
/* Do encryption in-place - this way we overwrite our copy of the plaintext
password */
deskey(fixedkey, EN0);
des(encryptedPasswd, encryptedPasswd);
}
void
vncEncryptPasswdMs( unsigned char *encryptedPasswd, char *passwd )
{
unsigned int i;
/* pad password with nulls */
for (i = 0; i < 32; i++) {
if (i < strlen(passwd)) {
encryptedPasswd[i] = passwd[i];
} else {
encryptedPasswd[i] = 0;
}
}
/* Do encryption in-place - this way we overwrite our copy of the plaintext
password */
deskey(fixedkey, EN0);
des(encryptedPasswd, encryptedPasswd);
}
/*
* Decrypt a password. Returns a pointer to a newly allocated
* string containing the password or a null pointer if the password could
* not be retrieved for some reason.
*/
char *
vncDecryptPasswd(const unsigned char *encryptedPasswd)
{
unsigned int i;
unsigned char *passwd = (unsigned char *)malloc(MAXPWLEN+1);
memcpy(passwd, encryptedPasswd, MAXPWLEN);
for (i = 0; i < MAXPWLEN; i++) {
passwd[i] = encryptedPasswd[i];
}
deskey(fixedkey, DE1);
des(passwd, passwd);
passwd[MAXPWLEN] = 0;
return (char *)passwd;
}
/*
* marscha@2006
* Encrypt bytes[length] in memory using key.
* Key has to be 8 bytes, length a multiple of 8 bytes.
*/
void
vncEncryptBytes2(unsigned char *where, const int length, unsigned char *key) {
int i, j;
deskey(key, EN0);
for (i = 0; i< 8; i++)
where[i] ^= key[i];
des(where, where);
for (i = 8; i < length; i += 8) {
for (j = 0; j < 8; j++)
where[i + j] ^= where[i + j - 8];
des(where + i, where + i);
}
}