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MAX_CARLINK_A270S/MXC_A27-PCB4.5-270S/lib/wolfssl/wolfcrypt/src/curve25519.c
2025-01-21 16:49:37 +08:00

721 lines
19 KiB
C

/* curve25519.c
*
* Copyright (C) 2006-2023 wolfSSL Inc.
*
* This file is part of wolfSSL.
*
* wolfSSL 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.
*
* wolfSSL 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
*/
/* Based On Daniel J Bernstein's curve25519 Public Domain ref10 work. */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <wolfssl/wolfcrypt/settings.h>
#ifdef HAVE_CURVE25519
#include <wolfssl/wolfcrypt/curve25519.h>
#include <wolfssl/wolfcrypt/error-crypt.h>
#ifdef NO_INLINE
#include <wolfssl/wolfcrypt/misc.h>
#else
#define WOLFSSL_MISC_INCLUDED
#include <wolfcrypt/src/misc.c>
#endif
#if defined(FREESCALE_LTC_ECC)
#include <wolfssl/wolfcrypt/port/nxp/ksdk_port.h>
#endif
#ifdef WOLFSSL_SE050
#include <wolfssl/wolfcrypt/port/nxp/se050_port.h>
#endif
#ifdef WOLF_CRYPTO_CB
#include <wolfssl/wolfcrypt/cryptocb.h>
#endif
#if defined(WOLFSSL_LINUXKM) && !defined(USE_INTEL_SPEEDUP)
/* force off unneeded vector register save/restore. */
#undef SAVE_VECTOR_REGISTERS
#define SAVE_VECTOR_REGISTERS(...) WC_DO_NOTHING
#undef RESTORE_VECTOR_REGISTERS
#define RESTORE_VECTOR_REGISTERS() WC_DO_NOTHING
#endif
const curve25519_set_type curve25519_sets[] = {
{
CURVE25519_KEYSIZE,
"CURVE25519",
}
};
static const word32 kCurve25519BasePoint[CURVE25519_KEYSIZE/sizeof(word32)] = {
#ifdef BIG_ENDIAN_ORDER
0x09000000
#else
9
#endif
};
/* Curve25519 private key must be less than order */
/* These functions clamp private k and check it */
static WC_INLINE int curve25519_priv_clamp(byte* priv)
{
priv[0] &= 248;
priv[CURVE25519_KEYSIZE-1] &= 127;
priv[CURVE25519_KEYSIZE-1] |= 64;
return 0;
}
static WC_INLINE int curve25519_priv_clamp_check(const byte* priv)
{
/* check that private part of key has been clamped */
int ret = 0;
if ((priv[0] & ~248) ||
(priv[CURVE25519_KEYSIZE-1] & 128)) {
ret = ECC_BAD_ARG_E;
}
return ret;
}
static WC_INLINE void curve25519_copy_point(byte* out, const byte* point,
int endian)
{
if (endian == EC25519_BIG_ENDIAN) {
int i;
/* put shared secret key in Big Endian format */
for (i = 0; i < CURVE25519_KEYSIZE; i++) {
out[i] = point[CURVE25519_KEYSIZE - i -1];
}
}
else { /* put shared secret key in Little Endian format */
XMEMCPY(out, point, CURVE25519_KEYSIZE);
}
}
/* compute the public key from an existing private key, using bare vectors.
*
* return value is propagated from curve25519() (0 on success), or
* ECC_BAD_ARG_E, and the byte vectors are little endian.
*/
int wc_curve25519_make_pub(int public_size, byte* pub, int private_size,
const byte* priv)
{
int ret;
#ifdef FREESCALE_LTC_ECC
const ECPoint* basepoint = nxp_ltc_curve25519_GetBasePoint();
ECPoint wc_pub;
#endif
if ( (public_size != CURVE25519_KEYSIZE) ||
(private_size != CURVE25519_KEYSIZE)) {
return ECC_BAD_ARG_E;
}
if ((pub == NULL) || (priv == NULL)) {
return ECC_BAD_ARG_E;
}
/* check clamping */
ret = curve25519_priv_clamp_check(priv);
if (ret != 0)
return ret;
#ifdef FREESCALE_LTC_ECC
/* input basepoint on Weierstrass curve */
ret = nxp_ltc_curve25519(&wc_pub, priv, basepoint, kLTC_Weierstrass);
if (ret == 0) {
XMEMCPY(pub, wc_pub.point, CURVE25519_KEYSIZE);
}
#else
fe_init();
SAVE_VECTOR_REGISTERS(return _svr_ret;);
ret = curve25519(pub, priv, (byte*)kCurve25519BasePoint);
RESTORE_VECTOR_REGISTERS();
#endif
return ret;
}
/* compute the public key from an existing private key, with supplied basepoint,
* using bare vectors.
*
* return value is propagated from curve25519() (0 on success),
* and the byte vectors are little endian.
*/
int wc_curve25519_generic(int public_size, byte* pub,
int private_size, const byte* priv,
int basepoint_size, const byte* basepoint)
{
#ifdef FREESCALE_LTC_ECC
/* unsupported with NXP LTC, only supports single basepoint with
* nxp_ltc_curve25519_GetBasePoint() */
return WC_HW_E;
#else
int ret;
if ((public_size != CURVE25519_KEYSIZE) ||
(private_size != CURVE25519_KEYSIZE) ||
(basepoint_size != CURVE25519_KEYSIZE)) {
return ECC_BAD_ARG_E;
}
if ((pub == NULL) || (priv == NULL) || (basepoint == NULL))
return ECC_BAD_ARG_E;
/* check clamping */
ret = curve25519_priv_clamp_check(priv);
if (ret != 0)
return ret;
fe_init();
SAVE_VECTOR_REGISTERS(return _svr_ret;);
ret = curve25519(pub, priv, basepoint);
RESTORE_VECTOR_REGISTERS();
return ret;
#endif /* FREESCALE_LTC_ECC */
}
/* generate a new private key, as a bare vector.
*
* return value is propagated from wc_RNG_GenerateBlock(() (0 on success),
* or BAD_FUNC_ARG/ECC_BAD_ARG_E, and the byte vector is little endian.
*/
int wc_curve25519_make_priv(WC_RNG* rng, int keysize, byte* key)
{
int ret;
if (key == NULL || rng == NULL)
return BAD_FUNC_ARG;
/* currently only a key size of 32 bytes is used */
if (keysize != CURVE25519_KEYSIZE)
return ECC_BAD_ARG_E;
/* random number for private key */
ret = wc_RNG_GenerateBlock(rng, key, (word32)keysize);
if (ret == 0) {
/* Clamp the private key */
ret = curve25519_priv_clamp(key);
}
return ret;
}
/* generate a new keypair.
*
* return value is propagated from wc_curve25519_make_private() or
* wc_curve25519_make_pub() (0 on success).
*/
int wc_curve25519_make_key(WC_RNG* rng, int keysize, curve25519_key* key)
{
int ret;
if (key == NULL || rng == NULL)
return BAD_FUNC_ARG;
#ifdef WOLF_CRYPTO_CB
if (key->devId != INVALID_DEVID) {
ret = wc_CryptoCb_Curve25519Gen(rng, keysize, key);
if (ret != WC_NO_ERR_TRACE(CRYPTOCB_UNAVAILABLE))
return ret;
/* fall-through when unavailable */
}
#endif
#ifdef WOLFSSL_SE050
ret = se050_curve25519_create_key(key, keysize);
#else
ret = wc_curve25519_make_priv(rng, keysize, key->k);
if (ret == 0) {
key->privSet = 1;
ret = wc_curve25519_make_pub((int)sizeof(key->p.point), key->p.point,
(int)sizeof(key->k), key->k);
key->pubSet = (ret == 0);
}
#endif
return ret;
}
#ifdef HAVE_CURVE25519_SHARED_SECRET
int wc_curve25519_shared_secret(curve25519_key* private_key,
curve25519_key* public_key,
byte* out, word32* outlen)
{
return wc_curve25519_shared_secret_ex(private_key, public_key,
out, outlen, EC25519_BIG_ENDIAN);
}
int wc_curve25519_shared_secret_ex(curve25519_key* private_key,
curve25519_key* public_key,
byte* out, word32* outlen, int endian)
{
int ret;
ECPoint o;
/* sanity check */
if (private_key == NULL || public_key == NULL ||
out == NULL || outlen == NULL || *outlen < CURVE25519_KEYSIZE) {
return BAD_FUNC_ARG;
}
/* make sure we have a populated private and public key */
if (!public_key->pubSet
#ifndef WOLFSSL_SE050
|| !private_key->privSet
#endif
) {
return ECC_BAD_ARG_E;
}
/* avoid implementation fingerprinting - make sure signed bit is not set */
if (public_key->p.point[CURVE25519_KEYSIZE-1] & 0x80) {
return ECC_BAD_ARG_E;
}
#ifdef WOLF_CRYPTO_CB
if (private_key->devId != INVALID_DEVID) {
ret = wc_CryptoCb_Curve25519(private_key, public_key, out, outlen,
endian);
if (ret != WC_NO_ERR_TRACE(CRYPTOCB_UNAVAILABLE))
return ret;
/* fall-through when unavailable */
}
#endif
XMEMSET(&o, 0, sizeof(o));
#ifdef FREESCALE_LTC_ECC
/* input point P on Curve25519 */
ret = nxp_ltc_curve25519(&o, private_key->k, &public_key->p,
kLTC_Curve25519);
#else
#ifdef WOLFSSL_SE050
if (!private_key->privSet) {
/* use NXP SE050: "privSet" is not set */
ret = se050_curve25519_shared_secret(private_key, public_key, &o);
}
else
#endif
{
SAVE_VECTOR_REGISTERS(return _svr_ret;);
ret = curve25519(o.point, private_key->k, public_key->p.point);
RESTORE_VECTOR_REGISTERS();
}
#endif
#ifdef WOLFSSL_ECDHX_SHARED_NOT_ZERO
if (ret == 0) {
int i;
byte t = 0;
for (i = 0; i < CURVE25519_KEYSIZE; i++) {
t |= o.point[i];
}
if (t == 0) {
ret = ECC_OUT_OF_RANGE_E;
}
}
#endif
if (ret == 0) {
curve25519_copy_point(out, o.point, endian);
*outlen = CURVE25519_KEYSIZE;
}
ForceZero(&o, sizeof(o));
return ret;
}
#endif /* HAVE_CURVE25519_SHARED_SECRET */
#ifdef HAVE_CURVE25519_KEY_EXPORT
/* export curve25519 public key (Big endian)
* return 0 on success */
int wc_curve25519_export_public(curve25519_key* key, byte* out, word32* outLen)
{
return wc_curve25519_export_public_ex(key, out, outLen, EC25519_BIG_ENDIAN);
}
/* export curve25519 public key (Big or Little endian)
* return 0 on success */
int wc_curve25519_export_public_ex(curve25519_key* key, byte* out,
word32* outLen, int endian)
{
int ret = 0;
if (key == NULL || out == NULL || outLen == NULL) {
return BAD_FUNC_ARG;
}
/* check and set outgoing key size */
if (*outLen < CURVE25519_KEYSIZE) {
*outLen = CURVE25519_KEYSIZE;
return ECC_BAD_ARG_E;
}
/* calculate public if missing */
if (!key->pubSet) {
ret = wc_curve25519_make_pub((int)sizeof(key->p.point), key->p.point,
(int)sizeof(key->k), key->k);
key->pubSet = (ret == 0);
}
/* export public point with endianness */
curve25519_copy_point(out, key->p.point, endian);
*outLen = CURVE25519_KEYSIZE;
return ret;
}
#endif /* HAVE_CURVE25519_KEY_EXPORT */
#ifdef HAVE_CURVE25519_KEY_IMPORT
/* import curve25519 public key (Big endian)
* return 0 on success */
int wc_curve25519_import_public(const byte* in, word32 inLen,
curve25519_key* key)
{
return wc_curve25519_import_public_ex(in, inLen, key, EC25519_BIG_ENDIAN);
}
/* import curve25519 public key (Big or Little endian)
* return 0 on success */
int wc_curve25519_import_public_ex(const byte* in, word32 inLen,
curve25519_key* key, int endian)
{
#ifdef FREESCALE_LTC_ECC
ltc_pkha_ecc_point_t ltcPoint;
#endif
/* sanity check */
if (key == NULL || in == NULL) {
return BAD_FUNC_ARG;
}
/* check size of incoming keys */
if (inLen != CURVE25519_KEYSIZE) {
return ECC_BAD_ARG_E;
}
/* import public point with endianness */
curve25519_copy_point(key->p.point, in, endian);
key->pubSet = 1;
key->dp = &curve25519_sets[0];
/* LTC needs also Y coordinate - let's compute it */
#ifdef FREESCALE_LTC_ECC
ltcPoint.X = &key->p.point[0];
ltcPoint.Y = &key->p.pointY[0];
LTC_PKHA_Curve25519ComputeY(&ltcPoint);
#endif
return 0;
}
/* Check the public key value (big or little endian)
*
* pub Public key bytes.
* pubSz Size of public key in bytes.
* endian Public key bytes passed in as big-endian or little-endian.
* returns BAD_FUNC_ARGS when pub is NULL,
* BUFFER_E when size of public key is zero;
* ECC_OUT_OF_RANGE_E if the high bit is set;
* ECC_BAD_ARG_E if key length is not 32 bytes, public key value is
* zero or one; and
* 0 otherwise.
*/
int wc_curve25519_check_public(const byte* pub, word32 pubSz, int endian)
{
word32 i;
if (pub == NULL)
return BAD_FUNC_ARG;
/* Check for empty key data */
if (pubSz == 0)
return BUFFER_E;
/* Check key length */
if (pubSz != CURVE25519_KEYSIZE)
return ECC_BAD_ARG_E;
if (endian == EC25519_LITTLE_ENDIAN) {
/* Check for value of zero or one */
for (i = CURVE25519_KEYSIZE - 1; i > 0; i--) {
if (pub[i] != 0)
break;
}
if (i == 0 && (pub[0] == 0 || pub[0] == 1))
return ECC_BAD_ARG_E;
/* Check high bit set */
if (pub[CURVE25519_KEYSIZE - 1] & 0x80)
return ECC_OUT_OF_RANGE_E;
/* Check for order-1 or higher. */
if (pub[CURVE25519_KEYSIZE - 1] == 0x7f) {
for (i = CURVE25519_KEYSIZE - 2; i > 0; i--) {
if (pub[i] != 0xff)
break;
}
if (i == 0 && (pub[0] >= 0xec))
return ECC_BAD_ARG_E;
}
}
else {
/* Check for value of zero or one */
for (i = 0; i < CURVE25519_KEYSIZE - 1; i++) {
if (pub[i] != 0)
break;
}
if (i == CURVE25519_KEYSIZE - 1 && (pub[i] == 0 || pub[i] == 1))
return ECC_BAD_ARG_E;
/* Check high bit set */
if (pub[0] & 0x80)
return ECC_OUT_OF_RANGE_E;
/* Check for order-1 or higher. */
if (pub[0] == 0x7f) {
for (i = 1; i < CURVE25519_KEYSIZE - 1; i++) {
if (pub[i] != 0)
break;
}
if (i == CURVE25519_KEYSIZE - 1 && (pub[i] >= 0xec))
return ECC_BAD_ARG_E;
}
}
return 0;
}
#endif /* HAVE_CURVE25519_KEY_IMPORT */
#ifdef HAVE_CURVE25519_KEY_EXPORT
/* export curve25519 private key only raw (Big endian)
* outLen is in/out size
* return 0 on success */
int wc_curve25519_export_private_raw(curve25519_key* key, byte* out,
word32* outLen)
{
return wc_curve25519_export_private_raw_ex(key, out, outLen,
EC25519_BIG_ENDIAN);
}
/* export curve25519 private key only raw (Big or Little endian)
* outLen is in/out size
* return 0 on success */
int wc_curve25519_export_private_raw_ex(curve25519_key* key, byte* out,
word32* outLen, int endian)
{
/* sanity check */
if (key == NULL || out == NULL || outLen == NULL)
return BAD_FUNC_ARG;
/* check size of outgoing buffer */
if (*outLen < CURVE25519_KEYSIZE) {
*outLen = CURVE25519_KEYSIZE;
return ECC_BAD_ARG_E;
}
/* export private scalar with endianness */
curve25519_copy_point(out, key->k, endian);
*outLen = CURVE25519_KEYSIZE;
return 0;
}
/* curve25519 key pair export (Big or Little endian)
* return 0 on success */
int wc_curve25519_export_key_raw(curve25519_key* key,
byte* priv, word32 *privSz,
byte* pub, word32 *pubSz)
{
return wc_curve25519_export_key_raw_ex(key, priv, privSz,
pub, pubSz, EC25519_BIG_ENDIAN);
}
/* curve25519 key pair export (Big or Little endian)
* return 0 on success */
int wc_curve25519_export_key_raw_ex(curve25519_key* key,
byte* priv, word32 *privSz,
byte* pub, word32 *pubSz,
int endian)
{
int ret;
/* export private part */
ret = wc_curve25519_export_private_raw_ex(key, priv, privSz, endian);
if (ret != 0)
return ret;
/* export public part */
return wc_curve25519_export_public_ex(key, pub, pubSz, endian);
}
#endif /* HAVE_CURVE25519_KEY_EXPORT */
#ifdef HAVE_CURVE25519_KEY_IMPORT
/* curve25519 private key import (Big endian)
* Public key to match private key needs to be imported too
* return 0 on success */
int wc_curve25519_import_private_raw(const byte* priv, word32 privSz,
const byte* pub, word32 pubSz,
curve25519_key* key)
{
return wc_curve25519_import_private_raw_ex(priv, privSz, pub, pubSz,
key, EC25519_BIG_ENDIAN);
}
/* curve25519 private key import (Big or Little endian)
* Public key to match private key needs to be imported too
* return 0 on success */
int wc_curve25519_import_private_raw_ex(const byte* priv, word32 privSz,
const byte* pub, word32 pubSz,
curve25519_key* key, int endian)
{
int ret;
/* import private part */
ret = wc_curve25519_import_private_ex(priv, privSz, key, endian);
if (ret != 0)
return ret;
/* import public part */
return wc_curve25519_import_public_ex(pub, pubSz, key, endian);
}
/* curve25519 private key import only. (Big endian)
* return 0 on success */
int wc_curve25519_import_private(const byte* priv, word32 privSz,
curve25519_key* key)
{
return wc_curve25519_import_private_ex(priv, privSz,
key, EC25519_BIG_ENDIAN);
}
/* curve25519 private key import only. (Big or Little endian)
* return 0 on success */
int wc_curve25519_import_private_ex(const byte* priv, word32 privSz,
curve25519_key* key, int endian)
{
/* sanity check */
if (key == NULL || priv == NULL) {
return BAD_FUNC_ARG;
}
/* check size of incoming keys */
if ((int)privSz != CURVE25519_KEYSIZE) {
return ECC_BAD_ARG_E;
}
#ifdef WOLFSSL_SE050
/* release NXP resources if set */
se050_curve25519_free_key(key);
#endif
/* import private scalar with endianness */
curve25519_copy_point(key->k, priv, endian);
key->privSet = 1;
key->dp = &curve25519_sets[0];
/* Clamp the key */
return curve25519_priv_clamp(key->k);
}
#endif /* HAVE_CURVE25519_KEY_IMPORT */
int wc_curve25519_init_ex(curve25519_key* key, void* heap, int devId)
{
if (key == NULL)
return BAD_FUNC_ARG;
XMEMSET(key, 0, sizeof(*key));
/* currently the format for curve25519 */
key->dp = &curve25519_sets[0];
#ifdef WOLF_CRYPTO_CB
key->devId = devId;
#else
(void)devId;
#endif
(void)heap; /* if needed for XMALLOC/XFREE in future */
#ifndef FREESCALE_LTC_ECC
fe_init();
#endif
#ifdef WOLFSSL_CHECK_MEM_ZERO
wc_MemZero_Add("wc_curve25519_init_ex key->k", key->k, CURVE25519_KEYSIZE);
#endif
return 0;
}
int wc_curve25519_init(curve25519_key* key)
{
return wc_curve25519_init_ex(key, NULL, INVALID_DEVID);
}
/* Clean the memory of a key */
void wc_curve25519_free(curve25519_key* key)
{
if (key == NULL)
return;
#ifdef WOLFSSL_SE050
se050_curve25519_free_key(key);
#endif
key->dp = NULL;
ForceZero(key->k, sizeof(key->k));
XMEMSET(&key->p, 0, sizeof(key->p));
key->pubSet = 0;
key->privSet = 0;
#ifdef WOLFSSL_CHECK_MEM_ZERO
wc_MemZero_Check(key, sizeof(curve25519_key));
#endif
}
/* get key size */
int wc_curve25519_size(curve25519_key* key)
{
if (key == NULL)
return 0;
return key->dp->size;
}
#endif /*HAVE_CURVE25519*/