NetBSD-5.0.2/crypto/dist/heimdal/lib/hcrypto/rsa-gmp.c
/*
* Copyright (c) 2006 - 2007 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
__RCSID("$Heimdal$"
"$NetBSD: rsa-gmp.c,v 1.1 2008/03/22 09:39:27 mlelstv Exp $");
#include <stdio.h>
#include <stdlib.h>
#include <krb5-types.h>
#include <assert.h>
#include <rsa.h>
#include <roken.h>
#ifdef HAVE_GMP
#include <gmp.h>
static void
BN2mpz(mpz_t s, const BIGNUM *bn)
{
size_t len;
void *p;
len = BN_num_bytes(bn);
p = malloc(len);
BN_bn2bin(bn, p);
mpz_import(s, len, 1, 1, 1, 0, p);
free(p);
}
static BIGNUM *
mpz2BN(mpz_t s)
{
size_t size;
BIGNUM *bn;
void *p;
mpz_export(NULL, &size, 1, 1, 1, 0, s);
p = malloc(size);
if (p == NULL && size != 0)
return NULL;
mpz_export(p, &size, 1, 1, 1, 0, s);
bn = BN_bin2bn(p, size, NULL);
free(p);
return bn;
}
static int
rsa_private_calculate(mpz_t in, mpz_t p, mpz_t q,
mpz_t dmp1, mpz_t dmq1, mpz_t iqmp,
mpz_t out)
{
mpz_t vp, vq, u;
mpz_init(vp); mpz_init(vq); mpz_init(u);
/* vq = c ^ (d mod (q - 1)) mod q */
/* vp = c ^ (d mod (p - 1)) mod p */
mpz_fdiv_r(vp, m, p);
mpz_powm(vp, vp, dmp1, p);
mpz_fdiv_r(vq, m, q);
mpz_powm(vq, vq, dmq1, q);
/* C2 = 1/q mod p (iqmp) */
/* u = (vp - vq)C2 mod p. */
mpz_sub(u, vp, vq);
#if 0
if (mp_int_compare_zero(&u) < 0)
mp_int_add(&u, p, &u);
#endif
mpz_mul(u, iqmp, u);
mpz_fdiv_r(u, u, p);
/* c ^ d mod n = vq + u q */
mpz_mul(u, q, u);
mpz_add(out, x, xq);
mpz_clear(vp);
mpz_clear(vq);
mpz_clear(u);
return 0;
}
/*
*
*/
static int
gmp_rsa_public_encrypt(int flen, const unsigned char* from,
unsigned char* to, RSA* rsa, int padding)
{
unsigned char *p, *p0;
mp_result res;
size_t size, padlen;
mpz_t enc, dec, n, e;
if (padding != RSA_PKCS1_PADDING)
return -1;
size = RSA_size(rsa);
if (size < RSA_PKCS1_PADDING_SIZE || size - RSA_PKCS1_PADDING_SIZE < flen)
return -2;
BN2mpz(n, rsa->n);
BN2mpz(e, rsa->e);
p = p0 = malloc(size - 1);
if (p0 == NULL) {
mpz_clear(e);
mpz_clear(n);
return -3;
}
padlen = size - flen - 3;
assert(padlen >= 8);
*p++ = 2;
if (RAND_bytes(p, padlen) != 1) {
mpz_clear(e);
mpz_clear(n);
free(p0);
return -4;
}
while(padlen) {
if (*p == 0)
*p = 1;
padlen--;
p++;
}
*p++ = 0;
memcpy(p, from, flen);
p += flen;
assert((p - p0) == size - 1);
mpz_init(enc);
mpz_init(dec);
mpz_import(dec, size - 1, 1, 1, 1, 0, p0);
free(p0);
mpz_powm(enc, dec, e, n);
mpz_clear(dec);
mpz_clear(e);
mpz_clear(n);
{
size_t ssize;
mpz_export(to, &ssize, 1, 1, 1, 0, enc);
assert(size >= ssize);
size = ssize;
}
mpz_clear(enc);
return size;
}
static int
gmp_rsa_public_decrypt(int flen, const unsigned char* from,
unsigned char* to, RSA* rsa, int padding)
{
unsigned char *p;
size_t size;
mpz_t s, us, n, e;
if (padding != RSA_PKCS1_PADDING)
return -1;
if (flen > RSA_size(rsa))
return -2;
BN2mpz(n, rsa->n);
BN2mpz(e, rsa->e);
#if 0
/* Check that the exponent is larger then 3 */
if (mp_int_compare_value(&e, 3) <= 0) {
mp_int_clear(&n);
mp_int_clear(&e);
return -3;
}
#endif
mpz_init(s);
mpz_init(us);
mpz_import(s, flen, 1, 1, 1, 0, rk_UNCONST(from));
if (mpz_cmp(s, n) >= 0) {
mpz_clear(n);
mpz_clear(e);
return -4;
}
mpz_powm(us, s, e, n);
mpz_clear(s);
mpz_clear(n);
mpz_clear(e);
p = to;
mpz_export(p, &size, 1, 1, 1, 0, us);
assert(size <= RSA_size(rsa));
mpz_clear(us);
/* head zero was skipped by mp_int_to_unsigned */
if (*p == 0)
return -6;
if (*p != 1)
return -7;
size--; p++;
while (size && *p == 0xff) {
size--; p++;
}
if (size == 0 || *p != 0)
return -8;
size--; p++;
memmove(to, p, size);
return size;
}
static int
gmp_rsa_private_encrypt(int flen, const unsigned char* from,
unsigned char* to, RSA* rsa, int padding)
{
unsigned char *p, *p0;
size_t size;
mpz_t in, out, n, e, b, bi;
if (padding != RSA_PKCS1_PADDING)
return -1;
size = RSA_size(rsa);
if (size < RSA_PKCS1_PADDING_SIZE || size - RSA_PKCS1_PADDING_SIZE < flen)
return -2;
p0 = p = malloc(size);
*p++ = 0;
*p++ = 1;
memset(p, 0xff, size - flen - 3);
p += size - flen - 3;
*p++ = 0;
memcpy(p, from, flen);
p += flen;
assert((p - p0) == size);
BN2mpz(&n, rsa->n);
BN2mpz(&e, rsa->e);
mp_int_init(&in);
mp_int_init(&out);
mpz_import(in, size, 1, 1, 1, 0, p0);
free(p0);
#if 0
if(mp_int_compare_zero(&in) < 0 ||
mp_int_compare(&in, &n) >= 0) {
size = 0;
goto out;
}
#endif
if (rsa->p && rsa->q && rsa->dmp1 && rsa->dmq1 && rsa->iqmp) {
mpz_t p, q, dmp1, dmq1, iqmp;
BN2mpz(p, rsa->p);
BN2mpz(q, rsa->q);
BN2mpz(dmp1, rsa->dmp1);
BN2mpz(dmq1, rsa->dmq1);
BN2mpz(iqmp, rsa->iqmp);
rsa_private_calculate(in, p, q, dmp1, dmq1, iqmp, out);
mp_int_clear(&p);
mp_int_clear(&q);
mp_int_clear(&dmp1);
mp_int_clear(&dmq1);
mp_int_clear(&iqmp);
} else {
mpz_t d;
BN2mpz(d, rsa->d);
mpz_powm(out, in, d, n);
mp_int_clear(d);
if (res != MP_OK) {
size = 0;
goto out;
}
}
{
size_t ssize;
mpz_export(to, &ssize, 1, 1, 1, 0, out);
assert(size >= ssize);
size = ssize;
}
out:
mpz_clear(e);
mpz_clear(n);
mpz_clear(in);
mpz_clear(out);
return size;
}
static int
gmp_rsa_private_decrypt(int flen, const unsigned char* from,
unsigned char* to, RSA* rsa, int padding)
{
unsigned char *ptr;
size_t size;
mpz_t in, out, n, e, b, bi;
if (padding != RSA_PKCS1_PADDING)
return -1;
size = RSA_size(rsa);
if (flen > size)
return -2;
mpz_init(in);
mpz_init(out);
BN2mpz(n, rsa->n);
BN2mpz(e, rsa->e);
res = mp_int_read_unsigned(&in, rk_UNCONST(from), flen);
if (res != MP_OK) {
size = -1;
goto out;
}
if(mp_int_compare_zero(&in) < 0 ||
mp_int_compare(&in, &n) >= 0) {
size = 0;
goto out;
}
if (rsa->p && rsa->q && rsa->dmp1 && rsa->dmq1 && rsa->iqmp) {
mpz_t p, q, dmp1, dmq1, iqmp;
BN2mpz(p, rsa->p);
BN2mpz(q, rsa->q);
BN2mpz(dmp1, rsa->dmp1);
BN2mpz(dmq1, rsa->dmq1);
BN2mpz(iqmp, rsa->iqmp);
res = rsa_private_calculate(in, p, q, dmp1, dmq1, iqmp, out);
mpz_clear(p);
mpz_clear(q);
mpz_clear(dmp1);
mpz_clear(dmq1);
mpz_clear(iqmp);
} else {
mpz_t d;
#if 0
if(mp_int_compare_zero(&in) < 0 ||
mp_int_compare(&in, &n) >= 0)
return MP_RANGE;
#endif
BN2mpz(d, rsa->d);
mpz_powm(out, in, d, n);
mp_int_clear(d);
if (res != MP_OK) {
size = 0;
goto out;
}
}
ptr = to;
{
size_t ssize;
mpz_export(ptr, &ssize, 1, 1, 1, 0, out);
assert(size >= ssize);
size = ssize;
}
/* head zero was skipped by mp_int_to_unsigned */
if (*ptr != 2)
return -3;
size--; ptr++;
while (size && *ptr != 0) {
size--; ptr++;
}
if (size == 0)
return -4;
size--; ptr++;
memmove(to, ptr, size);
out:
mpz_clear(e);
mpz_clear(n);
mpz_clear(in);
mpz_clear(out);
return size;
}
static int
gmp_rsa_generate_key(RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb)
{
mpz_t el, p, q, n, d, dmp1, dmq1, iqmp, t1, t2, t3;
int counter, ret;
if (bits < 789)
return -1;
ret = -1;
mpz_init(el);
mpz_init(p);
mpz_init(q);
mpz_init(n);
mpz_init(d);
mpz_init(dmp1);
mpz_init(dmq1);
mpz_init(iqmp);
mpz_init(t1);
mpz_init(t2);
mpz_init(t3);
BN2mpz(el, e);
/* generate p and q so that p != q and bits(pq) ~ bits */
counter = 0;
#if 0
do {
BN_GENCB_call(cb, 2, counter++);
CHECK(random_num(&p, bits / 2 + 1), 0);
CHECK(mp_int_find_prime(&p), MP_TRUE);
CHECK(mp_int_sub_value(&p, 1, &t1), MP_OK);
CHECK(mp_int_gcd(&t1, &el, &t2), MP_OK);
} while(mp_int_compare_value(&t2, 1) != 0);
BN_GENCB_call(cb, 3, 0);
counter = 0;
do {
BN_GENCB_call(cb, 2, counter++);
CHECK(random_num(&q, bits / 2 + 1), 0);
CHECK(mp_int_find_prime(&q), MP_TRUE);
if (mp_int_compare(&p, &q) == 0) /* don't let p and q be the same */
continue;
CHECK(mp_int_sub_value(&q, 1, &t1), MP_OK);
CHECK(mp_int_gcd(&t1, &el, &t2), MP_OK);
} while(mp_int_compare_value(&t2, 1) != 0);
/* make p > q */
if (mp_int_compare(&p, &q) < 0)
mp_int_swap(&p, &q);
BN_GENCB_call(cb, 3, 1);
/* calculate n, n = p * q */
CHECK(mp_int_mul(&p, &q, &n), MP_OK);
/* calculate d, d = 1/e mod (p - 1)(q - 1) */
CHECK(mp_int_sub_value(&p, 1, &t1), MP_OK);
CHECK(mp_int_sub_value(&q, 1, &t2), MP_OK);
CHECK(mp_int_mul(&t1, &t2, &t3), MP_OK);
CHECK(mp_int_invmod(&el, &t3, &d), MP_OK);
/* calculate dmp1 dmp1 = d mod (p-1) */
CHECK(mp_int_mod(&d, &t1, &dmp1), MP_OK);
/* calculate dmq1 dmq1 = d mod (q-1) */
CHECK(mp_int_mod(&d, &t2, &dmq1), MP_OK);
/* calculate iqmp iqmp = 1/q mod p */
CHECK(mp_int_invmod(&q, &p, &iqmp), MP_OK);
/* fill in RSA key */
rsa->e = mpz2BN(&el);
rsa->p = mpz2BN(&p);
rsa->q = mpz2BN(&q);
rsa->n = mpz2BN(&n);
rsa->d = mpz2BN(&d);
rsa->dmp1 = mpz2BN(&dmp1);
rsa->dmq1 = mpz2BN(&dmq1);
rsa->iqmp = mpz2BN(&iqmp);
ret = 1;
#endif
out:
mpz_clear(el);
mpz_clear(p);
mpz_clear(q);
mpz_clear(n);
mpz_clear(d);
mpz_clear(dmp1);
mpz_clear(dmq1);
mpz_clear(iqmp);
mpz_clear(t1);
mpz_clear(t2);
mpz_clear(t3);
return ret;
}
static int
gmp_rsa_init(RSA *rsa)
{
return 1;
}
static int
gmp_rsa_finish(RSA *rsa)
{
return 1;
}
const RSA_METHOD hc_rsa_gmp_method = {
"hcrypto GMP RSA",
gmp_rsa_public_encrypt,
gmp_rsa_public_decrypt,
gmp_rsa_private_encrypt,
gmp_rsa_private_decrypt,
NULL,
NULL,
gmp_rsa_init,
gmp_rsa_finish,
0,
NULL,
NULL,
NULL,
gmp_rsa_generate_key
};
#endif /* HAVE_GMP */
/**
* RSA implementation using Gnu Multipresistion Library.
*/
const RSA_METHOD *
RSA_gmp_method(void)
{
#ifdef HAVE_GMP
return &hc_rsa_gmp_method;
#else
return NULL;
#endif
}