gstreamer/gst/librfb/vncauth.c
2011-05-20 00:16:00 +03:00

177 lines
3.6 KiB
C

/*
* Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
*
* This 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 software 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.
*/
/*
* vncauth.c - Functions for VNC password management and authentication.
*/
#include "config.h"
#include <glib.h>
#include "_stdint.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "time.h"
#include "vncauth.h"
#include "d3des.h"
#include "sys/stat.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 a password and store it in a file. Returns 0 if successful,
* 1 if the file could not be written.
*/
int32_t
vncEncryptAndStorePasswd (char *passwd, char *fname)
{
FILE *fp;
uint32_t i;
unsigned char encryptedPasswd[8];
if ((fp = fopen (fname, "w")) == NULL)
return 1;
chmod (fname, S_IRUSR | S_IWUSR);
/* pad password with nulls */
for (i = 0; i < 8; 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);
for (i = 0; i < 8; i++) {
putc (encryptedPasswd[i], fp);
}
fclose (fp);
return 0;
}
/*
* Decrypt a password from a file. 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 *
vncDecryptPasswdFromFile (char *fname)
{
FILE *fp;
int32_t i, ch;
unsigned char *passwd;
if ((fp = fopen (fname, "r")) == NULL)
return NULL;
passwd = (unsigned char *) malloc (9);
for (i = 0; i < 8; i++) {
ch = getc (fp);
if (ch == EOF) {
fclose (fp);
free (passwd);
return NULL;
}
passwd[i] = ch;
}
fclose (fp);
deskey (fixedkey, DE1);
des (passwd, passwd);
passwd[8] = 0;
return (char *) passwd;
}
/*
* Generate CHALLENGESIZE random bytes for use in challenge-response
* authentication.
*/
void
vncRandomBytes (unsigned char *bytes)
{
int32_t i;
uint32_t seed = (uint32_t) time (0);
#ifndef G_OS_WIN32
srandom (seed);
#else
srand (seed);
#endif
for (i = 0; i < CHALLENGESIZE; i++) {
#ifndef G_OS_WIN32
bytes[i] = (unsigned char) (random () & 255);
#else
bytes[i] = (unsigned char) (rand () & 255);
#endif
}
}
/*
* Encrypt CHALLENGESIZE bytes in memory using a password.
*/
void
vncEncryptBytes (unsigned char *bytes, char *passwd)
{
unsigned char key[8];
uint32_t 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);
}
}