/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* curve 25519 https://www.rfc-editor.org/rfc/rfc7748.txt */
#ifdef FREEBL_NO_DEPEND
#include "../stubs.h"
#endif
#include "ecl-priv.h"
#include "secitem.h"
#include "secerr.h"
#include "secport.h"
#include <stdlib.h>
#include <stdio.h>
/*
* point validation is not necessary in general. But this checks a point (px)
* against some known bad values.
*/
SECStatus
ec_Curve25519_pt_validate(
const SECItem *px)
{
PRUint8 *p;
PRUint64 i;
PRUint8 forbiddenValues[12][32] = {
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
{ 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
{ 0xe0, 0xeb, 0x7a, 0x7c, 0x3b, 0x41, 0xb8, 0xae,
0x16, 0x56, 0xe3, 0xfa, 0xf1, 0x9f, 0xc4, 0x6a,
0xda, 0x09, 0x8d, 0xeb, 0x9c, 0x32, 0xb1, 0xfd,
0x86, 0x62, 0x05, 0x16, 0x5f, 0x49, 0xb8, 0x00 },
{ 0x5f, 0x9c, 0x95, 0xbc, 0xa3, 0x50, 0x8c, 0x24,
0xb1, 0xd0, 0xb1, 0x55, 0x9c, 0x83, 0xef, 0x5b,
0x04, 0x44, 0x5c, 0xc4, 0x58, 0x1c, 0x8e, 0x86,
0xd8, 0x22, 0x4e, 0xdd, 0xd0, 0x9f, 0x11, 0x57 },
{ 0xec, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
{ 0xed, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
{ 0xee, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
{ 0xcd, 0xeb, 0x7a, 0x7c, 0x3b, 0x41, 0xb8, 0xae,
0x16, 0x56, 0xe3, 0xfa, 0xf1, 0x9f, 0xc4, 0x6a,
0xda, 0x09, 0x8d, 0xeb, 0x9c, 0x32, 0xb1, 0xfd,
0x86, 0x62, 0x05, 0x16, 0x5f, 0x49, 0xb8, 0x80 },
{ 0x4c, 0x9c, 0x95, 0xbc, 0xa3, 0x50, 0x8c, 0x24,
0xb1, 0xd0, 0xb1, 0x55, 0x9c, 0x83, 0xef, 0x5b,
0x04, 0x44, 0x5c, 0xc4, 0x58, 0x1c, 0x8e, 0x86,
0xd8, 0x22, 0x4e, 0xdd, 0xd0, 0x9f, 0x11, 0xd7 },
{ 0xd9, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
{ 0xda, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
{ 0xdb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
};
if (px->len == 32) {
p = px->data;
}
else {
return SECFailure;
}
for (i = 0; i < PR_ARRAY_SIZE(forbiddenValues); ++i) {
if (NSS_SecureMemcmp(p, forbiddenValues[i], px->len) == 0) {
return SECFailure;
}
}
return SECSuccess;
}
/*
* scalar validation is not necessary.
*/
SECStatus
ec_Curve25519_scalar_validate(
const SECItem *scalar)
{
if (!scalar || !scalar->data) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
if (scalar->len != 32) {
PORT_SetError(SEC_ERROR_BAD_KEY);
return SECFailure;
}
return SECSuccess;
}
/*
* Scalar multiplication for Curve25519.
* If P == NULL, the base point is used.
* Returns X = k*P
*/
SECStatus
ec_Curve25519_pt_mul(SECItem *X, SECItem *k, SECItem *P)
{
PRUint8 *px;
PRUint8 basePoint[32] = { 9 };
if (!P) {
px = basePoint;
}
else {
PORT_Assert(P->len == 32);
if (P->len != 32) {
return SECFailure;
}
px = P->data;
}
if (k->len != 32) {
return SECFailure;
}
SECStatus rv = ec_Curve25519_mul(X->data, k->data, px);
if (NSS_SecureMemcmpZero(X->data, X->len) == 0) {
return SECFailure;
}
return rv;
}
