TheArchive/session-android
1
0
Fork 0
mirror of https://github.com/oxen-io/session-android.git synced 2025-08-11 20:47:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

clean & refactor session protocol encryption

Browse Source
This commit is contained in:
Ryan ZHAO
2021-03-12 13:37:16 +11:00
parent 60f51af295
commit 91f9138d62
21 changed files with 105 additions and 111 deletions
Download Patch File Download Diff File Expand all files Collapse all files

46
libsession/src/main/java/org/session/libsession/messaging/sending_receiving/MessageSenderEncryption.kt
View File

@@ -1,11 +1,53 @@
package org.session.libsession.messaging.sending_receiving
import com.goterl.lazycode.lazysodium.LazySodiumAndroid
import com.goterl.lazycode.lazysodium.SodiumAndroid
import com.goterl.lazycode.lazysodium.interfaces.Box
import com.goterl.lazycode.lazysodium.interfaces.Sign
import org.session.libsession.messaging.MessagingConfiguration
import org.session.libsession.messaging.sending_receiving.MessageSender.Error
import org.session.libsession.utilities.KeyPairUtilities
import org.session.libsignal.service.loki.utilities.removing05PrefixIfNeeded
import org.session.libsignal.utilities.Hex
import org.session.libsignal.utilities.logging.Log
object MessageSenderEncryption {
internal fun encryptWithSessionProtocol(plaintext: ByteArray, recipientPublicKey: String): ByteArray{
return MessagingConfiguration.shared.sessionProtocol.encrypt(plaintext, recipientPublicKey)
private val sodium by lazy { LazySodiumAndroid(SodiumAndroid()) }
/**
* Encrypts `plaintext` using the Session protocol for `hexEncodedX25519PublicKey`.
*
* @param plaintext the plaintext to encrypt. Must already be padded.
* @param recipientHexEncodedX25519PublicKey the X25519 public key to encrypt for. Could be the Session ID of a user, or the public key of a closed group.
*
* @return the encrypted message.
*/
internal fun encryptWithSessionProtocol(plaintext: ByteArray, recipientHexEncodedX25519PublicKey: String): ByteArray{
val context = MessagingConfiguration.shared.context
val userED25519KeyPair = KeyPairUtilities.getUserED25519KeyPair(context) ?: throw Error.NoUserED25519KeyPair
val recipientX25519PublicKey = Hex.fromStringCondensed(recipientHexEncodedX25519PublicKey.removing05PrefixIfNeeded())
val verificationData = plaintext + userED25519KeyPair.publicKey.asBytes + recipientX25519PublicKey
val signature = ByteArray(Sign.BYTES)
try {
sodium.cryptoSignDetached(signature, verificationData, verificationData.size.toLong(), userED25519KeyPair.secretKey.asBytes)
} catch (exception: Exception) {
Log.d("Loki", "Couldn't sign message due to error: $exception.")
throw Error.SigningFailed
}
val plaintextWithMetadata = plaintext + userED25519KeyPair.publicKey.asBytes + signature
val ciphertext = ByteArray(plaintextWithMetadata.size + Box.SEALBYTES)
try {
sodium.cryptoBoxSeal(ciphertext, plaintextWithMetadata, plaintextWithMetadata.size.toLong(), recipientX25519PublicKey)
} catch (exception: Exception) {
Log.d("Loki", "Couldn't encrypt message due to error: $exception.")
throw Error.EncryptionFailed
}
return ciphertext
}
}

111
libsession/src/main/java/org/session/libsession/utilities/IdentityKeyUtil.java Normal file
View File

@@ -0,0 +1,111 @@
/*
* Copyright (C) 2011 Whisper Systems
* Copyright (C) 2013 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/>.
*/
package org.session.libsession.utilities;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import androidx.annotation.NonNull;
import org.session.libsignal.libsignal.ecc.ECPublicKey;
import org.session.libsignal.libsignal.IdentityKey;
import org.session.libsignal.libsignal.IdentityKeyPair;
import org.session.libsignal.libsignal.InvalidKeyException;
import org.session.libsignal.libsignal.ecc.Curve;
import org.session.libsignal.libsignal.ecc.ECKeyPair;
import org.session.libsignal.libsignal.ecc.ECPrivateKey;
import org.session.libsignal.utilities.Base64;
import java.io.IOException;
/**
* Utility class for working with identity keys.
*
* @author Moxie Marlinspike
*/
public class IdentityKeyUtil {
private static final String MASTER_SECRET_UTIL_PREFERENCES_NAME = "SecureSMS-Preferences";
@SuppressWarnings("unused")
private static final String TAG = IdentityKeyUtil.class.getSimpleName();
public static final String IDENTITY_PUBLIC_KEY_PREF = "pref_identity_public_v3";
public static final String IDENTITY_PRIVATE_KEY_PREF = "pref_identity_private_v3";
public static final String ED25519_PUBLIC_KEY = "pref_ed25519_public_key";
public static final String ED25519_SECRET_KEY = "pref_ed25519_secret_key";
public static final String LOKI_SEED = "loki_seed";
public static boolean hasIdentityKey(Context context) {
SharedPreferences preferences = context.getSharedPreferences(MASTER_SECRET_UTIL_PREFERENCES_NAME, 0);
return
preferences.contains(IDENTITY_PUBLIC_KEY_PREF) &&
preferences.contains(IDENTITY_PRIVATE_KEY_PREF);
}
public static @NonNull IdentityKey getIdentityKey(@NonNull Context context) {
if (!hasIdentityKey(context)) throw new AssertionError("There isn't one!");
try {
byte[] publicKeyBytes = Base64.decode(retrieve(context, IDENTITY_PUBLIC_KEY_PREF));
return new IdentityKey(publicKeyBytes, 0);
} catch (IOException | InvalidKeyException e) {
throw new AssertionError(e);
}
}
public static @NonNull IdentityKeyPair getIdentityKeyPair(@NonNull Context context) {
if (!hasIdentityKey(context)) throw new AssertionError("There isn't one!");
try {
IdentityKey publicKey = getIdentityKey(context);
ECPrivateKey privateKey = Curve.decodePrivatePoint(Base64.decode(retrieve(context, IDENTITY_PRIVATE_KEY_PREF)));
return new IdentityKeyPair(publicKey, privateKey);
} catch (IOException e) {
throw new AssertionError(e);
}
}
public static void generateIdentityKeyPair(@NonNull Context context) {
ECKeyPair keyPair = Curve.generateKeyPair();
ECPublicKey publicKey = keyPair.getPublicKey();
ECPrivateKey privateKey = keyPair.getPrivateKey();
save(context, IDENTITY_PUBLIC_KEY_PREF, Base64.encodeBytes(publicKey.serialize()));
save(context, IDENTITY_PRIVATE_KEY_PREF, Base64.encodeBytes(privateKey.serialize()));
}
public static String retrieve(Context context, String key) {
SharedPreferences preferences = context.getSharedPreferences(MASTER_SECRET_UTIL_PREFERENCES_NAME, 0);
return preferences.getString(key, null);
}
public static void save(Context context, String key, String value) {
SharedPreferences preferences = context.getSharedPreferences(MASTER_SECRET_UTIL_PREFERENCES_NAME, 0);
Editor preferencesEditor = preferences.edit();
preferencesEditor.putString(key, value);
if (!preferencesEditor.commit()) throw new AssertionError("failed to save identity key/value to shared preferences");
}
public static void delete(Context context, String key) {
context.getSharedPreferences(MASTER_SECRET_UTIL_PREFERENCES_NAME, 0).edit().remove(key).commit();
}
}

60
libsession/src/main/java/org/session/libsession/utilities/KeyPairUtilities.kt Normal file
View File

@@ -0,0 +1,60 @@
package org.session.libsession.utilities
import android.content.Context
import com.goterl.lazycode.lazysodium.LazySodiumAndroid
import com.goterl.lazycode.lazysodium.SodiumAndroid
import com.goterl.lazycode.lazysodium.utils.Key
import com.goterl.lazycode.lazysodium.utils.KeyPair
import org.session.libsignal.utilities.Base64
import org.session.libsignal.utilities.Hex
import org.session.libsignal.libsignal.ecc.DjbECPrivateKey
import org.session.libsignal.libsignal.ecc.DjbECPublicKey
import org.session.libsignal.libsignal.ecc.ECKeyPair
object KeyPairUtilities {
private val sodium by lazy { LazySodiumAndroid(SodiumAndroid()) }
fun generate(): KeyPairGenerationResult {
val seed = sodium.randomBytesBuf(16)
try {
return generate(seed)
} catch (exception: Exception) {
return generate()
}
}
fun generate(seed: ByteArray): KeyPairGenerationResult {
val padding = ByteArray(16) { 0 }
val ed25519KeyPair = sodium.cryptoSignSeedKeypair(seed + padding)
val sodiumX25519KeyPair = sodium.convertKeyPairEd25519ToCurve25519(ed25519KeyPair)
val x25519KeyPair = ECKeyPair(DjbECPublicKey(sodiumX25519KeyPair.publicKey.asBytes), DjbECPrivateKey(sodiumX25519KeyPair.secretKey.asBytes))
return KeyPairGenerationResult(seed, ed25519KeyPair, x25519KeyPair)
}
fun store(context: Context, seed: ByteArray, ed25519KeyPair: KeyPair, x25519KeyPair: ECKeyPair) {
IdentityKeyUtil.save(context, IdentityKeyUtil.LOKI_SEED, Hex.toStringCondensed(seed))
IdentityKeyUtil.save(context, IdentityKeyUtil.IDENTITY_PUBLIC_KEY_PREF, Base64.encodeBytes(x25519KeyPair.publicKey.serialize()))
IdentityKeyUtil.save(context, IdentityKeyUtil.IDENTITY_PRIVATE_KEY_PREF, Base64.encodeBytes(x25519KeyPair.privateKey.serialize()))
IdentityKeyUtil.save(context, IdentityKeyUtil.ED25519_PUBLIC_KEY, Base64.encodeBytes(ed25519KeyPair.publicKey.asBytes))
IdentityKeyUtil.save(context, IdentityKeyUtil.ED25519_SECRET_KEY, Base64.encodeBytes(ed25519KeyPair.secretKey.asBytes))
}
fun hasV2KeyPair(context: Context): Boolean {
return (IdentityKeyUtil.retrieve(context, IdentityKeyUtil.ED25519_SECRET_KEY) != null)
}
fun getUserED25519KeyPair(context: Context): KeyPair? {
val base64EncodedED25519PublicKey = IdentityKeyUtil.retrieve(context, IdentityKeyUtil.ED25519_PUBLIC_KEY) ?: return null
val base64EncodedED25519SecretKey = IdentityKeyUtil.retrieve(context, IdentityKeyUtil.ED25519_SECRET_KEY) ?: return null
val ed25519PublicKey = Key.fromBytes(Base64.decode(base64EncodedED25519PublicKey))
val ed25519SecretKey = Key.fromBytes(Base64.decode(base64EncodedED25519SecretKey))
return KeyPair(ed25519PublicKey, ed25519SecretKey)
}
data class KeyPairGenerationResult(
val seed: ByteArray,
val ed25519KeyPair: KeyPair,
val x25519KeyPair: ECKeyPair
)
}