session-android/libaxolotl/jni/curve25519-jni.c
Moxie Marlinspike 27b5bf54cc Remove 1 mod 8.
2014-10-20 12:25:39 -07:00

109 lines
4.6 KiB
C

/**
* Copyright (C) 2013-2014 Open Whisper Systems
*
* This program 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 3 of the License, or
* (at your option) any later version.
*
* This program 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, see <http://www.gnu.org/licenses/>.
*/
#include <string.h>
#include <stdint.h>
#include <jni.h>
#include "curve25519-donna.h"
#include "curve_sigs.h"
JNIEXPORT jbyteArray JNICALL Java_org_whispersystems_libaxolotl_ecc_Curve25519_generatePrivateKey
(JNIEnv *env, jclass clazz, jbyteArray random)
{
uint8_t* privateKey = (uint8_t*)(*env)->GetByteArrayElements(env, random, 0);
privateKey[0] &= 248;
privateKey[31] &= 127;
privateKey[31] |= 64;
(*env)->ReleaseByteArrayElements(env, random, privateKey, 0);
return random;
}
JNIEXPORT jbyteArray JNICALL Java_org_whispersystems_libaxolotl_ecc_Curve25519_generatePublicKey
(JNIEnv *env, jclass clazz, jbyteArray privateKey)
{
static const uint8_t basepoint[32] = {9};
jbyteArray publicKey = (*env)->NewByteArray(env, 32);
uint8_t* publicKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, publicKey, 0);
uint8_t* privateKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, privateKey, 0);
curve25519_donna(publicKeyBytes, privateKeyBytes, basepoint);
(*env)->ReleaseByteArrayElements(env, publicKey, publicKeyBytes, 0);
(*env)->ReleaseByteArrayElements(env, privateKey, privateKeyBytes, 0);
return publicKey;
}
JNIEXPORT jbyteArray JNICALL Java_org_whispersystems_libaxolotl_ecc_Curve25519_calculateAgreement
(JNIEnv *env, jclass clazz, jbyteArray privateKey, jbyteArray publicKey)
{
jbyteArray sharedKey = (*env)->NewByteArray(env, 32);
uint8_t* sharedKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, sharedKey, 0);
uint8_t* privateKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, privateKey, 0);
uint8_t* publicKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, publicKey, 0);
curve25519_donna(sharedKeyBytes, privateKeyBytes, publicKeyBytes);
(*env)->ReleaseByteArrayElements(env, sharedKey, sharedKeyBytes, 0);
(*env)->ReleaseByteArrayElements(env, publicKey, publicKeyBytes, 0);
(*env)->ReleaseByteArrayElements(env, privateKey, privateKeyBytes, 0);
return sharedKey;
}
JNIEXPORT jbyteArray JNICALL Java_org_whispersystems_libaxolotl_ecc_Curve25519_calculateSignature
(JNIEnv *env, jclass clazz, jbyteArray random, jbyteArray privateKey, jbyteArray message)
{
jbyteArray signature = (*env)->NewByteArray(env, 64);
uint8_t* signatureBytes = (uint8_t*)(*env)->GetByteArrayElements(env, signature, 0);
uint8_t* randomBytes = (uint8_t*)(*env)->GetByteArrayElements(env, random, 0);
uint8_t* privateKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, privateKey, 0);
uint8_t* messageBytes = (uint8_t*)(*env)->GetByteArrayElements(env, message, 0);
jsize messageLength = (*env)->GetArrayLength(env, message);
curve25519_sign(signatureBytes, privateKeyBytes, messageBytes, messageLength, randomBytes);
(*env)->ReleaseByteArrayElements(env, signature, signatureBytes, 0);
(*env)->ReleaseByteArrayElements(env, random, randomBytes, 0);
(*env)->ReleaseByteArrayElements(env, privateKey, privateKeyBytes, 0);
(*env)->ReleaseByteArrayElements(env, message, messageBytes, 0);
return signature;
}
JNIEXPORT jboolean JNICALL Java_org_whispersystems_libaxolotl_ecc_Curve25519_verifySignature
(JNIEnv *env, jclass clazz, jbyteArray publicKey, jbyteArray message, jbyteArray signature)
{
uint8_t* signatureBytes = (uint8_t*)(*env)->GetByteArrayElements(env, signature, 0);
uint8_t* publicKeyBytes = (uint8_t*)(*env)->GetByteArrayElements(env, publicKey, 0);
uint8_t* messageBytes = (uint8_t*)(*env)->GetByteArrayElements(env, message, 0);
jsize messageLength = (*env)->GetArrayLength(env, message);
jboolean result = (curve25519_verify(signatureBytes, publicKeyBytes, messageBytes, messageLength) == 0);
(*env)->ReleaseByteArrayElements(env, signature, signatureBytes, 0);
(*env)->ReleaseByteArrayElements(env, publicKey, publicKeyBytes, 0);
(*env)->ReleaseByteArrayElements(env, message, messageBytes, 0);
return result;
}