306 lines
9.3 KiB
C
306 lines
9.3 KiB
C
/*
|
|
* Copyright (c) 1996
|
|
* Bill Paul <wpaul@ctr.columbia.edu>. 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.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Bill Paul.
|
|
* 4. Neither the name of the author nor the names of any co-contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY Bill Paul 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 Bill Paul 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/types.h>
|
|
#include <sys/param.h>
|
|
#include <dirent.h>
|
|
#include <dlfcn.h>
|
|
#include <err.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <rpc/des_crypt.h>
|
|
#include <rpc/des.h>
|
|
#include "crypt.h"
|
|
|
|
#ifndef lint
|
|
static const char rcsid[] =
|
|
"$FreeBSD$";
|
|
#endif /* not lint */
|
|
|
|
/*
|
|
* The U.S. government stupidly believes that a) it can keep strong
|
|
* crypto code a secret and b) that doing so somehow protects national
|
|
* interests. It's wrong on both counts, but until it listens to reason
|
|
* we have to make certain compromises so it doesn't have an excuse to
|
|
* throw us in federal prison.
|
|
*
|
|
* Consequently, the core OS ships without DES support, and keyserv
|
|
* defaults to using ARCFOUR with only a 40 bit key, just like nutscrape.
|
|
* This breaks compatibility with Secure RPC on other systems, but it
|
|
* allows Secure RPC to work between FreeBSD systems that don't have the
|
|
* DES package installed without throwing security totally out the window.
|
|
*
|
|
* In order to avoid having to supply two versions of keyserv (one with
|
|
* DES and one without), we use dlopen() and friends to load libdes.so
|
|
* into our address space at runtime. We check for the presence of
|
|
* /usr/lib/libdes.so.3.0 at startup and load it if we find it. If we
|
|
* can't find it, or the __des_crypt symbol doesn't exist, we fall back
|
|
* to the ARCFOUR encryption code. The user can specify another path using
|
|
* the -p flag.
|
|
*/
|
|
|
|
/* arcfour.h */
|
|
typedef struct arcfour_key
|
|
{
|
|
unsigned char state[256];
|
|
unsigned char x;
|
|
unsigned char y;
|
|
} arcfour_key;
|
|
|
|
static void prepare_key(unsigned char *key_data_ptr,int key_data_len,
|
|
arcfour_key *key);
|
|
static void arcfour(unsigned char *buffer_ptr,int buffer_len,arcfour_key * key);
|
|
static void swap_byte(unsigned char *a, unsigned char *b);
|
|
|
|
static void prepare_key(unsigned char *key_data_ptr, int key_data_len,
|
|
arcfour_key *key)
|
|
{
|
|
unsigned char index1;
|
|
unsigned char index2;
|
|
unsigned char* state;
|
|
short counter;
|
|
|
|
state = &key->state[0];
|
|
for(counter = 0; counter < 256; counter++)
|
|
state[counter] = counter;
|
|
key->x = 0;
|
|
key->y = 0;
|
|
index1 = 0;
|
|
index2 = 0;
|
|
for(counter = 0; counter < 256; counter++)
|
|
{
|
|
index2 = (key_data_ptr[index1] + state[counter] +
|
|
index2) % 256;
|
|
swap_byte(&state[counter], &state[index2]);
|
|
|
|
index1 = (index1 + 1) % key_data_len;
|
|
}
|
|
}
|
|
|
|
static void arcfour(unsigned char *buffer_ptr, int buffer_len, arcfour_key *key)
|
|
{
|
|
unsigned char x;
|
|
unsigned char y;
|
|
unsigned char* state;
|
|
unsigned char xorIndex;
|
|
short counter;
|
|
|
|
x = key->x;
|
|
y = key->y;
|
|
|
|
state = &key->state[0];
|
|
for(counter = 0; counter < buffer_len; counter ++)
|
|
{
|
|
x = (x + 1) % 256;
|
|
y = (state[x] + y) % 256;
|
|
swap_byte(&state[x], &state[y]);
|
|
|
|
xorIndex = (state[x] + state[y]) % 256;
|
|
|
|
buffer_ptr[counter] ^= state[xorIndex];
|
|
}
|
|
key->x = x;
|
|
key->y = y;
|
|
}
|
|
|
|
static void swap_byte(unsigned char *a, unsigned char *b)
|
|
{
|
|
unsigned char swapByte;
|
|
|
|
swapByte = *a;
|
|
*a = *b;
|
|
*b = swapByte;
|
|
}
|
|
|
|
/* Dummy _des_crypt function that uses ARCFOUR with a 40 bit key */
|
|
int _arcfour_crypt(buf, len, desp)
|
|
char *buf;
|
|
int len;
|
|
struct desparams *desp;
|
|
{
|
|
struct arcfour_key arcfourk;
|
|
|
|
/*
|
|
* U.S. government anti-crypto weasels take
|
|
* note: although we are supplied with a 64 bit
|
|
* key, we're only passing 40 bits to the ARCFOUR
|
|
* encryption code. So there.
|
|
*/
|
|
prepare_key(desp->des_key, 5, &arcfourk);
|
|
arcfour(buf, len, &arcfourk);
|
|
|
|
return(DESERR_NOHWDEVICE);
|
|
}
|
|
|
|
int (*_my_crypt)__P((char *, int, struct desparams *)) = NULL;
|
|
|
|
static void *dlhandle;
|
|
|
|
#ifndef _PATH_USRLIB
|
|
#define _PATH_USRLIB "/usr/lib"
|
|
#endif
|
|
|
|
#ifndef LIBCRYPTO
|
|
#ifdef OBJFORMAT_ELF
|
|
#define LIBCRYPTO "libcrypto.so.1"
|
|
#else
|
|
#define LIBCRYPTO "libcrypto.so.1."
|
|
#endif /* OBJFORMAT_ELF */
|
|
#endif
|
|
|
|
void load_des(warn, libpath)
|
|
int warn;
|
|
char *libpath;
|
|
{
|
|
char dlpath[MAXPATHLEN];
|
|
|
|
if (libpath == NULL) {
|
|
#ifdef OBJFORMAT_ELF
|
|
snprintf(dlpath, sizeof(dlpath), "%s/%s", _PATH_USRLIB, LIBCRYPTO);
|
|
#else
|
|
len = strlen(LIBCRYPTO);
|
|
if ((dird = opendir(_PATH_USRLIB)) == NULL)
|
|
err(1, "opendir(/usr/lib) failed");
|
|
|
|
while ((dirp = readdir(dird)) != NULL) {
|
|
/* must have a minor number */
|
|
if (strlen(dirp->d_name) <= len)
|
|
continue;
|
|
if (!strncmp(dirp->d_name, LIBCRYPTO, len)) {
|
|
if (atoi((dirp->d_name + len + 1)) > minor) {
|
|
minor = atoi((dirp->d_name + len + 1));
|
|
snprintf(dlpath,sizeof(dlpath),"%s/%s",
|
|
_PATH_USRLIB, dirp->d_name);
|
|
}
|
|
}
|
|
}
|
|
|
|
closedir(dird);
|
|
#endif /* OBJFORMAT_ELF */
|
|
} else
|
|
snprintf(dlpath, sizeof(dlpath), "%s", libpath);
|
|
|
|
if (dlpath != NULL && (dlhandle = dlopen(dlpath, 0444)) != NULL)
|
|
#ifdef OBJFORMAT_ELF
|
|
_my_crypt = (int (*)())dlsym(dlhandle, "_des_crypt");
|
|
#else
|
|
_my_crypt = (int (*)())dlsym(dlhandle, "__des_crypt");
|
|
#endif /* OBJFORMAT_ELF */
|
|
|
|
if (_my_crypt == NULL) {
|
|
if (dlhandle != NULL)
|
|
dlclose(dlhandle);
|
|
_my_crypt = &_arcfour_crypt;
|
|
if (warn) {
|
|
printf ("DES support disabled -- using ARCFOUR instead.\n");
|
|
printf ("Warning: ARCFOUR cipher is not compatible with ");
|
|
printf ("other Secure RPC implementations.\nInstall ");
|
|
printf ("the FreeBSD 'des' distribution to enable");
|
|
printf (" DES encryption.\n");
|
|
}
|
|
} else {
|
|
if (warn) {
|
|
printf ("DES support enabled\n");
|
|
printf ("Using %s shared object.\n", dlpath);
|
|
}
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
desresp *
|
|
des_crypt_1_svc(desargs *argp, struct svc_req *rqstp)
|
|
{
|
|
static desresp result;
|
|
struct desparams dparm;
|
|
|
|
if (argp->desbuf.desbuf_len > DES_MAXDATA) {
|
|
result.stat = DESERR_BADPARAM;
|
|
return(&result);
|
|
}
|
|
|
|
|
|
bcopy(argp->des_key, dparm.des_key, 8);
|
|
bcopy(argp->des_ivec, dparm.des_ivec, 8);
|
|
dparm.des_mode = argp->des_mode;
|
|
dparm.des_dir = argp->des_dir;
|
|
#ifdef BROKEN_DES
|
|
dparm.UDES.UDES_buf = argp->desbuf.desbuf_val;
|
|
#endif
|
|
|
|
/*
|
|
* XXX This compensates for a bug in the libdes Secure RPC
|
|
* compat interface. (Actually, there are a couple.) The
|
|
* des_ecb_encrypt() routine in libdes only encrypts 8 bytes
|
|
* (64 bits) at a time. However, the Sun Secure RPC ecb_crypt()
|
|
* routine is supposed to be able to handle buffers up to 8Kbytes.
|
|
* The rpc_enc module in libdes ignores this fact and just drops
|
|
* the length parameter on the floor, encrypting only the
|
|
* first 64 bits of whatever buffer you feed it. We deal with
|
|
* this here: if we're using DES encryption, and we're using
|
|
* ECB mode, then we make a pass over the entire buffer
|
|
* ourselves. Note: the rpc_enc module incorrectly transposes
|
|
* the mode flags, so when you ask for CBC mode, you're really
|
|
* getting ECB mode.
|
|
*/
|
|
#ifdef BROKEN_DES
|
|
if (_my_crypt != &_arcfour_crypt && argp->des_mode == CBC) {
|
|
#else
|
|
if (_my_crypt != &_arcfour_crypt && argp->des_mode == ECB) {
|
|
#endif
|
|
int i;
|
|
char *dptr;
|
|
|
|
for (i = 0; i < argp->desbuf.desbuf_len / 8; i++) {
|
|
dptr = argp->desbuf.desbuf_val;
|
|
dptr += (i * 8);
|
|
#ifdef BROKEN_DES
|
|
dparm.UDES.UDES_buf = dptr;
|
|
#endif
|
|
result.stat = _my_crypt(dptr, 8, &dparm);
|
|
}
|
|
} else {
|
|
result.stat = _my_crypt(argp->desbuf.desbuf_val,
|
|
argp->desbuf.desbuf_len,
|
|
&dparm);
|
|
}
|
|
|
|
if (result.stat == DESERR_NONE || result.stat == DESERR_NOHWDEVICE) {
|
|
bcopy(dparm.des_ivec, result.des_ivec, 8);
|
|
result.desbuf.desbuf_len = argp->desbuf.desbuf_len;
|
|
result.desbuf.desbuf_val = argp->desbuf.desbuf_val;
|
|
}
|
|
|
|
return (&result);
|
|
}
|