freebsd-dev/eBones/des/new_rnd_key.c
1995-09-16 20:44:27 +00:00

155 lines
4.5 KiB
C

/*
* Copyright (c) 1995
* Mark Murray. 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 Mark Murray
* and Eric Young
* 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 MARK MURRAY 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 THE REGENTS 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.
*
* $Id$
*/
#include <unistd.h>
#include <string.h>
#include <sys/time.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#include <machine/types.h>
#include "des_locl.h"
/* This counter keeps track of the pseudo-random sequence */
static union {
u_int32_t ul0, ul1;
u_char uc[8];
} counter;
/* The current encryption schedule */
static des_key_schedule current_key;
/*
* des_set_random_generator_seed: starts a new pseudorandom sequence
* dependant on the supplied key
*/
void
des_set_random_generator_seed(new_key)
des_cblock *new_key;
{
des_key_sched(new_key, current_key);
/* reset the counter */
counter.ul0 = counter.ul1 = 0;
}
/*
* des_set_sequence_number: set the counter to a known value
*/
void
des_set_sequence_number(new_counter)
des_cblock new_counter;
{
bcopy((void *)new_counter, (char *)counter.uc, sizeof(counter));
}
/*
* des_generate_random_block: returns the next 64 bit random number
*/
void des_generate_random_block(random_block)
des_cblock *random_block;
{
/* Encrypt the counter to get pseudo-random numbers */
des_ecb_encrypt(&counter.uc, random_block, current_key, DES_ENCRYPT);
/* increment the 64-bit counter */
counter.ul0++;
if (!counter.ul0) counter.ul1++;
}
/*
* des_new_random_key: Invents a new, random strong key with odd parity.
*/
int
des_new_random_key(new_key)
des_cblock *new_key;
{
do {
des_generate_random_block(new_key);
des_set_odd_parity(new_key);
} while (des_is_weak_key(new_key));
return(0);
}
/*
* des_init_random_number_generator: intialises the random number generator
* to a truly nasty sequence using system
* supplied volatile variables.
*/
void
des_init_random_number_generator(key)
des_cblock *key;
{
/* 64-bit structures */
struct {
u_int32_t pid;
u_int32_t hostid;
} sysblock;
struct timeval timeblock;
struct {
u_int32_t tv_sec;
u_int32_t tv_usec;
} time64bit;
des_cblock new_key;
int mib[2];
size_t len;
/* Get host ID using official BSD 4.4 method */
mib[0] = CTL_KERN;
mib[1] = KERN_HOSTID;
len = sizeof(sysblock.hostid);
sysctl(mib, 2, &sysblock.hostid, &len, NULL, 0);
/* Get Process ID */
sysblock.pid = getpid();
/* Generate a new key, and use it to seed the random generator */
des_set_random_generator_seed(key);
des_set_sequence_number((unsigned char *)&sysblock);
des_new_random_key(&new_key);
des_set_random_generator_seed(&new_key);
/* Try to confuse the sequence counter */
gettimeofday(&timeblock, NULL);
time64bit.tv_sec = (u_int32_t)timeblock.tv_sec;
time64bit.tv_usec = (u_int32_t)timeblock.tv_usec;
des_set_sequence_number((unsigned char *)&time64bit);
/* Do the work */
des_new_random_key(&new_key);
des_set_random_generator_seed(&new_key);
}