nmode's Git Repositories - signal-cli/blob - lib/src/main/java/org/asamk/signal/manager/util/KeyUtils.java

   1 package org.asamk.signal.manager.util;
   2
   3 import org.asamk.signal.manager.storage.SignalAccount;
   4 import org.signal.libsignal.protocol.IdentityKey;
   5 import org.signal.libsignal.protocol.IdentityKeyPair;
   6 import org.signal.libsignal.protocol.InvalidKeyException;
   7 import org.signal.libsignal.protocol.ecc.Curve;
   8 import org.signal.libsignal.protocol.ecc.ECPrivateKey;
   9 import org.signal.libsignal.protocol.kem.KEMKeyPair;
  10 import org.signal.libsignal.protocol.kem.KEMKeyType;
  11 import org.signal.libsignal.protocol.state.KyberPreKeyRecord;
  12 import org.signal.libsignal.protocol.state.PreKeyRecord;
  13 import org.signal.libsignal.protocol.state.SignedPreKeyRecord;
  14 import org.signal.libsignal.zkgroup.InvalidInputException;
  15 import org.signal.libsignal.zkgroup.profiles.ProfileKey;
  16 import org.whispersystems.signalservice.api.account.PreKeyCollection;
  17 import org.whispersystems.signalservice.api.backup.MediaRootBackupKey;
  18
  19 import java.security.SecureRandom;
  20 import java.util.ArrayList;
  21 import java.util.Base64;
  22 import java.util.List;
  23
  24 import static org.asamk.signal.manager.config.ServiceConfig.PREKEY_BATCH_SIZE;
  25 import static org.asamk.signal.manager.config.ServiceConfig.PREKEY_MAXIMUM_ID;
  26
  27 public class KeyUtils {
  28
  29     private static final SecureRandom secureRandom = new SecureRandom();
  30
  31     private KeyUtils() {
  32     }
  33
  34     public static IdentityKeyPair getIdentityKeyPair(byte[] publicKeyBytes, byte[] privateKeyBytes) {
  35         try {
  36             IdentityKey publicKey = new IdentityKey(publicKeyBytes);
  37             ECPrivateKey privateKey = Curve.decodePrivatePoint(privateKeyBytes);
  38
  39             return new IdentityKeyPair(publicKey, privateKey);
  40         } catch (InvalidKeyException e) {
  41             throw new AssertionError(e);
  42         }
  43     }
  44
  45     public static IdentityKeyPair generateIdentityKeyPair() {
  46         var djbKeyPair = Curve.generateKeyPair();
  47         var djbIdentityKey = new IdentityKey(djbKeyPair.getPublicKey());
  48         var djbPrivateKey = djbKeyPair.getPrivateKey();
  49
  50         return new IdentityKeyPair(djbIdentityKey, djbPrivateKey);
  51     }
  52
  53     public static List<PreKeyRecord> generatePreKeyRecords(final int offset) {
  54         var records = new ArrayList<PreKeyRecord>(PREKEY_BATCH_SIZE);
  55         for (var i = 0; i < PREKEY_BATCH_SIZE; i++) {
  56             var preKeyId = (offset + i) % PREKEY_MAXIMUM_ID;
  57             var keyPair = Curve.generateKeyPair();
  58             var record = new PreKeyRecord(preKeyId, keyPair);
  59
  60             records.add(record);
  61         }
  62         return records;
  63     }
  64
  65     public static SignedPreKeyRecord generateSignedPreKeyRecord(
  66             final int signedPreKeyId,
  67             final ECPrivateKey privateKey
  68     ) {
  69         var keyPair = Curve.generateKeyPair();
  70         byte[] signature;
  71         try {
  72             signature = Curve.calculateSignature(privateKey, keyPair.getPublicKey().serialize());
  73         } catch (InvalidKeyException e) {
  74             throw new AssertionError(e);
  75         }
  76         return new SignedPreKeyRecord(signedPreKeyId, System.currentTimeMillis(), keyPair, signature);
  77     }
  78
  79     public static List<KyberPreKeyRecord> generateKyberPreKeyRecords(final int offset, final ECPrivateKey privateKey) {
  80         var records = new ArrayList<KyberPreKeyRecord>(PREKEY_BATCH_SIZE);
  81         for (var i = 0; i < PREKEY_BATCH_SIZE; i++) {
  82             var preKeyId = (offset + i) % PREKEY_MAXIMUM_ID;
  83             records.add(generateKyberPreKeyRecord(preKeyId, privateKey));
  84         }
  85         return records;
  86     }
  87
  88     public static KyberPreKeyRecord generateKyberPreKeyRecord(final int preKeyId, final ECPrivateKey privateKey) {
  89         KEMKeyPair keyPair = KEMKeyPair.generate(KEMKeyType.KYBER_1024);
  90         byte[] signature = privateKey.calculateSignature(keyPair.getPublicKey().serialize());
  91
  92         return new KyberPreKeyRecord(preKeyId, System.currentTimeMillis(), keyPair, signature);
  93     }
  94
  95     public static ProfileKey createProfileKey() {
  96         try {
  97             return new ProfileKey(getSecretBytes(32));
  98         } catch (InvalidInputException e) {
  99             throw new AssertionError("Profile key is guaranteed to be 32 bytes here");
 100         }
 101     }
 102
 103     public static String createPassword() {
 104         return getSecret(18);
 105     }
 106
 107     public static byte[] createStickerUploadKey() {
 108         return getSecretBytes(32);
 109     }
 110
 111     public static MediaRootBackupKey createMediaRootBackupKey() {
 112         return new MediaRootBackupKey(getSecretBytes(32));
 113     }
 114
 115     public static byte[] createRawStorageId() {
 116         return getSecretBytes(16);
 117     }
 118
 119     private static String getSecret(int size) {
 120         var secret = getSecretBytes(size);
 121         return Base64.getEncoder().encodeToString(secret);
 122     }
 123
 124     public static byte[] getSecretBytes(int size) {
 125         var secret = new byte[size];
 126         secureRandom.nextBytes(secret);
 127         return secret;
 128     }
 129
 130     public static int getRandomInt(int bound) {
 131         return secureRandom.nextInt(bound);
 132     }
 133
 134     public static PreKeyCollection generatePreKeysForType(final SignalAccount.AccountData<?> accountData) {
 135         final var keyPair = accountData.getIdentityKeyPair();
 136         final var preKeyMetadata = accountData.getPreKeyMetadata();
 137
 138         final var nextSignedPreKeyId = preKeyMetadata.getNextSignedPreKeyId();
 139         final var signedPreKey = generateSignedPreKeyRecord(nextSignedPreKeyId, keyPair.getPrivateKey());
 140
 141         final var privateKey = keyPair.getPrivateKey();
 142         final var kyberPreKeyIdOffset = preKeyMetadata.getNextKyberPreKeyId();
 143         final var lastResortKyberPreKey = generateKyberPreKeyRecord(kyberPreKeyIdOffset, privateKey);
 144
 145         return new PreKeyCollection(keyPair.getPublicKey(), signedPreKey, lastResortKyberPreKey);
 146     }
 147 }