Refactoring to clarify the use of crypto functions

app/src/androidTest/java/com/vitorpamplona/amethyst/CryptoUtilsTest.kt

@@ -24,7 +24,7 @@ class CryptoUtilsTest {
         val privateKey = "f410f88bcec6cbfda04d6a273c7b1dd8bba144cd45b71e87109cfa11dd7ed561"
         val publicKey = "765cd7cf91d3ad07423d114d5a39c61d52b2cdbc18ba055ddbbeec71fbe2aa2f"
 
-        val key = CryptoUtils.getSharedSecretXChaCha(privateKey = privateKey.hexToByteArray(), pubKey = publicKey.hexToByteArray())
+        val key = CryptoUtils.getSharedSecretNIP24(privateKey = privateKey.hexToByteArray(), pubKey = publicKey.hexToByteArray())
 
         assertEquals("577c966f499dddd8e8dcc34e8f352e283cc177e53ae372794947e0b8ede7cfd8", key.toHexKey())
     }
@@ -34,8 +34,8 @@ class CryptoUtilsTest {
         val sender = KeyPair()
         val receiver = KeyPair()
 
-        val sharedSecret1 = CryptoUtils.getSharedSecretXChaCha(sender.privKey!!, receiver.pubKey)
+        val sharedSecret1 = CryptoUtils.getSharedSecretNIP24(sender.privKey!!, receiver.pubKey)
-        val sharedSecret2 = CryptoUtils.getSharedSecretXChaCha(receiver.privKey!!, sender.pubKey)
+        val sharedSecret2 = CryptoUtils.getSharedSecretNIP24(receiver.privKey!!, sender.pubKey)
 
         assertEquals(sharedSecret1.toHexKey(), sharedSecret2.toHexKey())
 
@@ -53,8 +53,8 @@ class CryptoUtilsTest {
         val privateKey = CryptoUtils.privkeyCreate()
         val publicKey = CryptoUtils.pubkeyCreate(privateKey)
 
-        val encrypted = CryptoUtils.encrypt(msg, privateKey, publicKey)
+        val encrypted = CryptoUtils.encryptNIP04(msg, privateKey, publicKey)
-        val decrypted = CryptoUtils.decrypt(encrypted, privateKey, publicKey)
+        val decrypted = CryptoUtils.decryptNIP04(encrypted, privateKey, publicKey)
 
         assertEquals(msg, decrypted)
     }
@@ -66,8 +66,8 @@ class CryptoUtilsTest {
         val privateKey = CryptoUtils.privkeyCreate()
         val publicKey = CryptoUtils.pubkeyCreate(privateKey)
 
-        val encrypted = CryptoUtils.encryptXChaCha(msg, privateKey, publicKey)
+        val encrypted = CryptoUtils.encryptNIP24(msg, privateKey, publicKey)
-        val decrypted = CryptoUtils.decryptXChaCha(encrypted, privateKey, publicKey)
+        val decrypted = CryptoUtils.decryptNIP24(encrypted, privateKey, publicKey)
 
         assertEquals(msg, decrypted)
     }
@@ -78,10 +78,10 @@ class CryptoUtilsTest {
 
         val privateKey = CryptoUtils.privkeyCreate()
         val publicKey = CryptoUtils.pubkeyCreate(privateKey)
-        val sharedSecret = CryptoUtils.getSharedSecret(privateKey, publicKey)
+        val sharedSecret = CryptoUtils.getSharedSecretNIP04(privateKey, publicKey)
 
-        val encrypted = CryptoUtils.encrypt(msg, sharedSecret)
+        val encrypted = CryptoUtils.encryptNIP04(msg, sharedSecret)
-        val decrypted = CryptoUtils.decrypt(encrypted, sharedSecret)
+        val decrypted = CryptoUtils.decryptNIP04(encrypted, sharedSecret)
 
         assertEquals(msg, decrypted)
     }
@@ -92,10 +92,10 @@ class CryptoUtilsTest {
 
         val privateKey = CryptoUtils.privkeyCreate()
         val publicKey = CryptoUtils.pubkeyCreate(privateKey)
-        val sharedSecret = CryptoUtils.getSharedSecretXChaCha(privateKey, publicKey)
+        val sharedSecret = CryptoUtils.getSharedSecretNIP24(privateKey, publicKey)
 
-        val encrypted = CryptoUtils.encryptXChaCha(msg, sharedSecret)
+        val encrypted = CryptoUtils.encryptNIP24(msg, sharedSecret)
-        val decrypted = CryptoUtils.decryptXChaCha(encrypted, sharedSecret)
+        val decrypted = CryptoUtils.decryptNIP24(encrypted, sharedSecret)
 
         assertEquals(msg, decrypted)
     }

app/src/androidTest/java/com/vitorpamplona/amethyst/GiftWrapEventTest.kt

@@ -1,6 +1,7 @@
 package com.vitorpamplona.amethyst
 
 import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.vitorpamplona.amethyst.model.HexKey
 import com.vitorpamplona.amethyst.model.hexToByteArray
 import com.vitorpamplona.amethyst.model.toHexKey
 import com.vitorpamplona.amethyst.service.CryptoUtils
@@ -8,6 +9,7 @@ import com.vitorpamplona.amethyst.service.KeyPair
 import com.vitorpamplona.amethyst.service.model.ChatMessageEvent
 import com.vitorpamplona.amethyst.service.model.Event
 import com.vitorpamplona.amethyst.service.model.GiftWrapEvent
+import com.vitorpamplona.amethyst.service.model.Gossip
 import com.vitorpamplona.amethyst.service.model.NIP24Factory
 import com.vitorpamplona.amethyst.service.model.SealedGossipEvent
 import com.vitorpamplona.amethyst.service.relays.Client
@@ -34,18 +36,6 @@ class GiftWrapEventTest {
             sender.privKey!!
         )
 
-        events.forEach {
-            if (it.recipientPubKey() == sender.pubKey.toHexKey()) {
-                println(sender.privKey!!.toHexKey())
-                println(it.toJson())
-            }
-
-            if (it.recipientPubKey() == receiver.pubKey.toHexKey()) {
-                println(receiver.privKey!!.toHexKey())
-                println(it.toJson())
-            }
-        }
-
         // Simulate Receiver
         val eventsReceiverGets = events.filter { it.isTaggedUser(receiver.pubKey.toHexKey()) }
         eventsReceiverGets.forEach {
@@ -424,23 +414,11 @@ class GiftWrapEventTest {
  }
         """.trimIndent()
 
-        val privateKey = "de6152a85a0dea3b09a08a6f8139a314d498a7b52f7e5c28858b64270abd4c70".hexToByteArray()
+        val privateKey = "de6152a85a0dea3b09a08a6f8139a314d498a7b52f7e5c28858b64270abd4c70"
-        val wrap = Event.fromJson(json, Client.lenient) as GiftWrapEvent
+        val gossip = unwrapUnsealGossip(json, privateKey)
 
-        wrap.checkSignature()
+        assertNotNull(gossip)
-
+        assertEquals("Hola, que tal?", gossip?.content)
-        assertEquals(CryptoUtils.pubkeyCreate(privateKey).toHexKey(), wrap.recipientPubKey())
-
-        val event = wrap.unwrap(privateKey)
-        assertNotNull(event)
-
-        if (event is SealedGossipEvent) {
-            val innerData = event.unseal(privateKey)
-            assertNotNull(innerData)
-            assertEquals("Hola, que tal?", innerData?.content)
-        } else {
-            fail("Inner event is not a Sealed Gossip")
-        }
     }
 
     @Test
@@ -462,23 +440,11 @@ class GiftWrapEventTest {
 }
         """.trimIndent()
 
-        val privateKey = "409ff7654141eaa16cd2161fe5bd127aeaef71f270c67587474b78998a8e3533".hexToByteArray()
+        val privateKey = "409ff7654141eaa16cd2161fe5bd127aeaef71f270c67587474b78998a8e3533"
-        val wrap = Event.fromJson(json, Client.lenient) as GiftWrapEvent
+        val gossip = unwrapUnsealGossip(json, privateKey)
 
-        wrap.checkSignature()
+        assertNotNull(gossip)
-
+        assertEquals("Hola, que tal?", gossip?.content)
-        assertEquals(CryptoUtils.pubkeyCreate(privateKey).toHexKey(), wrap.recipientPubKey())
-
-        val event = wrap.unwrap(privateKey)
-        assertNotNull(event)
-
-        if (event is SealedGossipEvent) {
-            val innerData = event.unseal(privateKey)
-            assertNotNull(innerData)
-            assertEquals("Hola, que tal?", innerData?.content)
-        } else {
-            fail("Inner event is not a Sealed Gossip")
-        }
     }
 
     @Test
@@ -503,24 +469,11 @@ class GiftWrapEventTest {
 }
         """.trimIndent()
 
-        val privateKey = "09e0051fdf5fdd9dd7a54713583006442cbdbf87bdcdab1a402f26e527d56771".hexToByteArray()
+        val privateKey = "09e0051fdf5fdd9dd7a54713583006442cbdbf87bdcdab1a402f26e527d56771"
-        val wrap = Event.fromJson(json, Client.lenient) as GiftWrapEvent
+        val gossip = unwrapUnsealGossip(json, privateKey)
 
-        wrap.checkSignature()
+        assertNotNull(gossip)
-
+        assertEquals("test", gossip?.content)
-        assertEquals(CryptoUtils.pubkeyCreate(privateKey).toHexKey(), wrap.recipientPubKey())
-
-        val event = wrap.unwrap(privateKey)
-        assertNotNull(event)
-
-        if (event is SealedGossipEvent) {
-            val innerData = event.unseal(privateKey)
-            assertNotNull(innerData)
-            assertEquals("test", innerData?.content)
-        } else {
-            println(event?.toJson())
-            fail()
-        }
     }
 
     @Test
@@ -542,28 +495,35 @@ class GiftWrapEventTest {
 }
         """.trimIndent()
 
-        val privateKey = "09e0051fdf5fdd9dd7a54713583006442cbdbf87bdcdab1a402f26e527d56771".hexToByteArray()
+        val privateKey = "09e0051fdf5fdd9dd7a54713583006442cbdbf87bdcdab1a402f26e527d56771"
-        val wrap = Event.fromJson(json, Client.lenient) as GiftWrapEvent
 
+        val gossip = unwrapUnsealGossip(json, privateKey)
+
+        assertEquals("asdfasdfasdf", gossip?.content)
+        assertEquals(0L, gossip?.createdAt)
+        assertEquals("827ba09d32ab81d62c60f657b350198c8aaba84372dab9ad3f4f6b8b7274b707", gossip?.id)
+        assertEquals(14, gossip?.kind)
+        assertEquals("subject", gossip?.tags?.firstOrNull()?.get(0))
+        assertEquals("test", gossip?.tags?.firstOrNull()?.get(1))
+    }
+
+    fun unwrapUnsealGossip(json: String, privateKey: HexKey): Gossip? {
+        val pkBytes = privateKey.hexToByteArray()
+
+        val wrap = Event.fromJson(json, Client.lenient) as GiftWrapEvent
         wrap.checkSignature()
 
-        assertEquals(CryptoUtils.pubkeyCreate(privateKey).toHexKey(), wrap.recipientPubKey())
+        assertEquals(CryptoUtils.pubkeyCreate(pkBytes).toHexKey(), wrap.recipientPubKey())
 
-        val event = wrap.unwrap(privateKey)
+        val event = wrap.unwrap(pkBytes)
         assertNotNull(event)
 
-        if (event is SealedGossipEvent) {
+        return if (event is SealedGossipEvent) {
-            val innerData = event.unseal(privateKey)
+            return event.unseal(pkBytes)
-            assertNotNull(innerData)
-            assertEquals("asdfasdfasdf", innerData?.content)
-            assertEquals(0L, innerData?.createdAt)
-            assertEquals("827ba09d32ab81d62c60f657b350198c8aaba84372dab9ad3f4f6b8b7274b707", innerData?.id)
-            assertEquals(14, innerData?.kind)
-            assertEquals("subject", innerData?.tags?.firstOrNull()?.get(0))
-            assertEquals("test", innerData?.tags?.firstOrNull()?.get(1))
         } else {
             println(event?.toJson())
-            fail()
+            fail("Event is not a Sealed Gossip")
+            null
         }
     }
 }

app/src/main/java/com/vitorpamplona/amethyst/service/CryptoUtils.kt

@@ -1,10 +1,6 @@
 package com.vitorpamplona.amethyst.service
 
-import com.goterl.lazysodium.LazySodium
-import com.goterl.lazysodium.LazySodiumAndroid
-import com.goterl.lazysodium.Sodium
 import com.goterl.lazysodium.SodiumAndroid
-import com.goterl.lazysodium.utils.Base64MessageEncoder
 import com.goterl.lazysodium.utils.Key
 import fr.acinq.secp256k1.Hex
 import fr.acinq.secp256k1.Secp256k1
@@ -34,86 +30,6 @@ object CryptoUtils {
     fun sign(data: ByteArray, privKey: ByteArray): ByteArray =
         secp256k1.signSchnorr(data, privKey, null)
 
-    fun encrypt(msg: String, privateKey: ByteArray, pubKey: ByteArray): String {
-        val sharedSecret = getSharedSecret(privateKey, pubKey)
-        return encrypt(msg, sharedSecret)
-    }
-
-    fun encrypt(msg: String, sharedSecret: ByteArray): String {
-        val iv = ByteArray(16)
-        random.nextBytes(iv)
-        val cipher = Cipher.getInstance("AES/CBC/PKCS5Padding")
-        cipher.init(Cipher.ENCRYPT_MODE, SecretKeySpec(sharedSecret, "AES"), IvParameterSpec(iv))
-        val ivBase64 = Base64.getEncoder().encodeToString(iv)
-        val encryptedMsg = cipher.doFinal(msg.toByteArray())
-        val encryptedMsgBase64 = Base64.getEncoder().encodeToString(encryptedMsg)
-        return "$encryptedMsgBase64?iv=$ivBase64"
-    }
-
-    fun decrypt(msg: String, privateKey: ByteArray, pubKey: ByteArray): String {
-        val sharedSecret = getSharedSecret(privateKey, pubKey)
-        return decrypt(msg, sharedSecret)
-    }
-
-    fun decrypt(msg: String, sharedSecret: ByteArray): String {
-        val parts = msg.split("?iv=")
-        val iv = parts[1].run { Base64.getDecoder().decode(this) }
-        val encryptedMsg = parts.first().run { Base64.getDecoder().decode(this) }
-        val cipher = Cipher.getInstance("AES/CBC/PKCS5Padding")
-        cipher.init(Cipher.DECRYPT_MODE, SecretKeySpec(sharedSecret, "AES"), IvParameterSpec(iv))
-        return String(cipher.doFinal(encryptedMsg))
-    }
-
-    fun encryptXChaCha(msg: String, privateKey: ByteArray, pubKey: ByteArray): EncryptedInfo {
-        val sharedSecret = getSharedSecretXChaCha(privateKey, pubKey)
-        return encryptXChaCha(msg, sharedSecret)
-    }
-
-    fun encryptXChaCha(msg: String, sharedSecret: ByteArray): EncryptedInfo {
-        val lazySodium = LazySodiumAndroid(SodiumAndroid(), Base64MessageEncoder())
-
-        val key = Key.fromBytes(sharedSecret)
-
-        val nonce: ByteArray = lazySodium.nonce(24)
-        val messageBytes: ByteArray = msg.toByteArray()
-
-        val cipher = lazySodium.cryptoStreamXChaCha20Xor(
-            messageBytes = messageBytes,
-            nonce = nonce,
-            key = key
-        )
-
-        val cipherBase64 = Base64.getEncoder().encodeToString(cipher)
-        val nonceBase64 = Base64.getEncoder().encodeToString(nonce)
-
-        return EncryptedInfo(
-            ciphertext = cipherBase64,
-            nonce = nonceBase64,
-            v = Nip44Version.XChaCha20.versionCode
-        )
-    }
-
-    fun decryptXChaCha(encryptedInfo: EncryptedInfo, privateKey: ByteArray, pubKey: ByteArray): String? {
-        val sharedSecret = getSharedSecretXChaCha(privateKey, pubKey)
-        return decryptXChaCha(encryptedInfo, sharedSecret)
-    }
-
-    fun decryptXChaCha(encryptedInfo: EncryptedInfo, sharedSecret: ByteArray): String? {
-        val lazySodium = LazySodiumAndroid(SodiumAndroid(), Base64MessageEncoder())
-
-        val key = Key.fromBytes(sharedSecret)
-        val nonceBytes = Base64.getDecoder().decode(encryptedInfo.nonce)
-        val messageBytes = Base64.getDecoder().decode(encryptedInfo.ciphertext)
-
-        val cipher = lazySodium.cryptoStreamXChaCha20Xor(
-            messageBytes = messageBytes,
-            nonce = nonceBytes,
-            key = key
-        )
-
-        return cipher?.decodeToString()
-    }
-
     fun verifySignature(
         signature: ByteArray,
         hash: ByteArray,
@@ -130,100 +46,87 @@ object CryptoUtils {
     /**
      * @return 32B shared secret
      */
-    fun getSharedSecret(privateKey: ByteArray, pubKey: ByteArray): ByteArray =
+    fun getSharedSecretNIP04(privateKey: ByteArray, pubKey: ByteArray): ByteArray =
         secp256k1.pubKeyTweakMul(Hex.decode("02") + pubKey, privateKey).copyOfRange(1, 33)
 
+    fun encryptNIP04(msg: String, privateKey: ByteArray, pubKey: ByteArray): String {
+        val sharedSecret = getSharedSecretNIP04(privateKey, pubKey)
+        return encryptNIP04(msg, sharedSecret)
+    }
+
+    fun encryptNIP04(msg: String, sharedSecret: ByteArray): String {
+        val iv = ByteArray(16)
+        random.nextBytes(iv)
+        val cipher = Cipher.getInstance("AES/CBC/PKCS5Padding")
+        cipher.init(Cipher.ENCRYPT_MODE, SecretKeySpec(sharedSecret, "AES"), IvParameterSpec(iv))
+        val ivBase64 = Base64.getEncoder().encodeToString(iv)
+        val encryptedMsg = cipher.doFinal(msg.toByteArray())
+        val encryptedMsgBase64 = Base64.getEncoder().encodeToString(encryptedMsg)
+        return "$encryptedMsgBase64?iv=$ivBase64"
+    }
+
+    fun decryptNIP04(msg: String, privateKey: ByteArray, pubKey: ByteArray): String {
+        val sharedSecret = getSharedSecretNIP04(privateKey, pubKey)
+        return decryptNIP04(msg, sharedSecret)
+    }
+
+    fun decryptNIP04(msg: String, sharedSecret: ByteArray): String {
+        val parts = msg.split("?iv=")
+        val iv = parts[1].run { Base64.getDecoder().decode(this) }
+        val encryptedMsg = parts.first().run { Base64.getDecoder().decode(this) }
+        val cipher = Cipher.getInstance("AES/CBC/PKCS5Padding")
+        cipher.init(Cipher.DECRYPT_MODE, SecretKeySpec(sharedSecret, "AES"), IvParameterSpec(iv))
+        return String(cipher.doFinal(encryptedMsg))
+    }
+
+    fun encryptNIP24(msg: String, privateKey: ByteArray, pubKey: ByteArray): EncryptedInfo {
+        val sharedSecret = getSharedSecretNIP24(privateKey, pubKey)
+        return encryptNIP24(msg, sharedSecret)
+    }
+
+    fun encryptNIP24(msg: String, sharedSecret: ByteArray): EncryptedInfo {
+        val nonce = ByteArray(24)
+        random.nextBytes(nonce)
+
+        val cipher = SodiumAndroid().cryptoStreamXChaCha20Xor(
+            messageBytes = msg.toByteArray(),
+            nonce = nonce,
+            key = Key.fromBytes(sharedSecret)
+        )
+
+        val cipherBase64 = Base64.getEncoder().encodeToString(cipher)
+        val nonceBase64 = Base64.getEncoder().encodeToString(nonce)
+
+        return EncryptedInfo(
+            ciphertext = cipherBase64,
+            nonce = nonceBase64,
+            v = Nip44Version.XChaCha20.versionCode
+        )
+    }
+
+    fun decryptNIP24(encryptedInfo: EncryptedInfo, privateKey: ByteArray, pubKey: ByteArray): String? {
+        val sharedSecret = getSharedSecretNIP24(privateKey, pubKey)
+        return decryptNIP24(encryptedInfo, sharedSecret)
+    }
+
+    fun decryptNIP24(encryptedInfo: EncryptedInfo, sharedSecret: ByteArray): String? {
+        return SodiumAndroid().cryptoStreamXChaCha20Xor(
+            messageBytes = Base64.getDecoder().decode(encryptedInfo.ciphertext),
+            nonce = Base64.getDecoder().decode(encryptedInfo.nonce),
+            key = Key.fromBytes(sharedSecret)
+        )?.decodeToString()
+    }
+
     /**
      * @return 32B shared secret
      */
-    fun getSharedSecretXChaCha(privateKey: ByteArray, pubKey: ByteArray): ByteArray =
+    fun getSharedSecretNIP24(privateKey: ByteArray, pubKey: ByteArray): ByteArray =
         sha256(secp256k1.pubKeyTweakMul(Hex.decode("02") + pubKey, privateKey).copyOfRange(1, 33))
 }
 
-fun Int.toByteArray(): ByteArray {
-    val bytes = ByteArray(4)
-    (0..3).forEach {
-        bytes[3 - it] = ((this ushr (8 * it)) and 0xFFFF).toByte()
-    }
-    return bytes
-}
-
 data class EncryptedInfo(val ciphertext: String, val nonce: String, val v: Int)
 
 enum class Nip44Version(val versionCode: Int) {
     Reserved(0),
     XChaCha20(1)
 }
-
-fun Sodium.crypto_stream_xchacha20_xor_ic(
-    cipher: ByteArray,
-    message: ByteArray,
-    messageLen: Long,
-    nonce: ByteArray,
-    ic: Long,
-    key: ByteArray
-): Int {
-    /**
-     *
-     *     unsigned char k2[crypto_core_hchacha20_OUTPUTBYTES];
-
-     crypto_core_hchacha20(k2, n, k, NULL);
-     return crypto_stream_chacha20_xor_ic(
-     c, m, mlen, n + crypto_core_hchacha20_INPUTBYTES, ic, k2);
-     */
-
-    val k2 = ByteArray(32)
-
-    val nonceChaCha = nonce.drop(16).toByteArray()
-    assert(nonceChaCha.size == 8)
-
-    crypto_core_hchacha20(k2, nonce, key, null)
-    return crypto_stream_chacha20_xor_ic(
-        cipher,
-        message,
-        messageLen,
-        nonceChaCha,
-        ic,
-        k2
-    )
-}
-
-fun Sodium.crypto_stream_xchacha20_xor(
-    cipher: ByteArray,
-    message: ByteArray,
-    messageLen: Long,
-    nonce: ByteArray,
-    key: ByteArray
-): Int {
-    return crypto_stream_xchacha20_xor_ic(cipher, message, messageLen, nonce, 0, key)
-}
-
-fun LazySodium.cryptoStreamXChaCha20Xor(
-    cipher: ByteArray,
-    message: ByteArray,
-    messageLen: Long,
-    nonce: ByteArray,
-    key: ByteArray
-): Boolean {
-    require(!(messageLen < 0 || messageLen > message.size)) { "messageLen out of bounds: $messageLen" }
-    return successful(
-        getSodium().crypto_stream_xchacha20_xor(
-            cipher,
-            message,
-            messageLen,
-            nonce,
-            key
-        )
-    )
-}
-
-private fun LazySodium.cryptoStreamXChaCha20Xor(
-    messageBytes: ByteArray,
-    nonce: ByteArray,
-    key: Key
-): ByteArray? {
-    val mLen = messageBytes.size
-    val cipher = ByteArray(mLen)
-    val sucessful = cryptoStreamXChaCha20Xor(cipher, messageBytes, mLen.toLong(), nonce, key.asBytes)
-    return if (sucessful) cipher else null
-}

app/src/main/java/com/vitorpamplona/amethyst/service/SodiumUtils.kt

@@ -0,0 +1,75 @@
+package com.vitorpamplona.amethyst.service
+
+import com.goterl.lazysodium.Sodium
+import com.goterl.lazysodium.SodiumAndroid
+import com.goterl.lazysodium.utils.Key
+
+fun Sodium.crypto_stream_xchacha20_xor_ic(
+    cipher: ByteArray,
+    message: ByteArray,
+    messageLen: Long,
+    nonce: ByteArray,
+    ic: Long,
+    key: ByteArray
+): Int {
+    /**
+     * C++ Code:
+     *
+     * unsigned char k2[crypto_core_hchacha20_OUTPUTBYTES];
+     * crypto_core_hchacha20(k2, n, k, NULL);
+     * return crypto_stream_chacha20_xor_ic(
+     * c, m, mlen, n + crypto_core_hchacha20_INPUTBYTES, ic, k2);
+     */
+    val k2 = ByteArray(32)
+
+    val nonceChaCha = nonce.drop(16).toByteArray()
+    assert(nonceChaCha.size == 8)
+
+    crypto_core_hchacha20(k2, nonce, key, null)
+    return crypto_stream_chacha20_xor_ic(
+        cipher,
+        message,
+        messageLen,
+        nonceChaCha,
+        ic,
+        k2
+    )
+}
+
+fun Sodium.crypto_stream_xchacha20_xor(
+    cipher: ByteArray,
+    message: ByteArray,
+    messageLen: Long,
+    nonce: ByteArray,
+    key: ByteArray
+): Int {
+    return crypto_stream_xchacha20_xor_ic(cipher, message, messageLen, nonce, 0, key)
+}
+
+fun SodiumAndroid.cryptoStreamXChaCha20Xor(
+    cipher: ByteArray,
+    message: ByteArray,
+    messageLen: Long,
+    nonce: ByteArray,
+    key: ByteArray
+): Boolean {
+    require(!(messageLen < 0 || messageLen > message.size)) { "messageLen out of bounds: $messageLen" }
+    return crypto_stream_xchacha20_xor(
+        cipher,
+        message,
+        messageLen,
+        nonce,
+        key
+    ) == 0
+}
+
+fun SodiumAndroid.cryptoStreamXChaCha20Xor(
+    messageBytes: ByteArray,
+    nonce: ByteArray,
+    key: Key
+): ByteArray? {
+    val mLen = messageBytes.size
+    val cipher = ByteArray(mLen)
+    val sucessful = cryptoStreamXChaCha20Xor(cipher, messageBytes, mLen.toLong(), nonce, key.asBytes)
+    return if (sucessful) cipher else null
+}

app/src/main/java/com/vitorpamplona/amethyst/service/model/ATag.kt

@@ -6,7 +6,7 @@ import com.vitorpamplona.amethyst.model.hexToByteArray
 import com.vitorpamplona.amethyst.model.toHexKey
 import com.vitorpamplona.amethyst.service.bechToBytes
 import com.vitorpamplona.amethyst.service.nip19.Tlv
-import com.vitorpamplona.amethyst.service.toByteArray
+import com.vitorpamplona.amethyst.service.nip19.toByteArray
 import com.vitorpamplona.amethyst.service.toNAddress
 import fr.acinq.secp256k1.Hex
 

app/src/main/java/com/vitorpamplona/amethyst/service/model/GeneralListEvent.kt

@@ -28,9 +28,9 @@ abstract class GeneralListEvent(
         if (content.isBlank()) return null
 
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecret(privKey, pubKey.hexToByteArray())
+            val sharedSecret = CryptoUtils.getSharedSecretNIP04(privKey, pubKey.hexToByteArray())
 
-            return CryptoUtils.decrypt(content, sharedSecret)
+            return CryptoUtils.decryptNIP04(content, sharedSecret)
         } catch (e: Exception) {
             Log.w("GeneralList", "Error decrypting the message ${e.message} for ${dTag()}")
             null
@@ -91,7 +91,7 @@ abstract class GeneralListEvent(
             }
             val msg = gson.toJson(privTags)
 
-            return CryptoUtils.encrypt(
+            return CryptoUtils.encryptNIP04(
                 msg,
                 privateKey,
                 pubKey
@@ -102,7 +102,7 @@ abstract class GeneralListEvent(
             privateTags: List<List<String>>? = null,
             privateKey: ByteArray
         ): String {
-            return CryptoUtils.encrypt(
+            return CryptoUtils.encryptNIP04(
                 msg = gson.toJson(privateTags),
                 privateKey = privateKey,
                 pubKey = CryptoUtils.pubkeyCreate(privateKey)

app/src/main/java/com/vitorpamplona/amethyst/service/model/GiftWrapEvent.kt

@@ -40,14 +40,14 @@ class GiftWrapEvent(
         if (content.isBlank()) return null
 
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecretXChaCha(privKey, pubKey.hexToByteArray())
+            val sharedSecret = CryptoUtils.getSharedSecretNIP24(privKey, pubKey.hexToByteArray())
 
             val toDecrypt = gson.fromJson<EncryptedInfo>(
                 content,
                 EncryptedInfo::class.java
             )
 
-            return CryptoUtils.decryptXChaCha(toDecrypt, sharedSecret)
+            return CryptoUtils.decryptNIP24(toDecrypt, sharedSecret)
         } catch (e: Exception) {
             Log.w("GeneralList", "Error decrypting the message ${e.message}")
             null
@@ -65,10 +65,10 @@ class GiftWrapEvent(
             createdAt: Long = TimeUtils.now()
         ): GiftWrapEvent {
             val privateKey = CryptoUtils.privkeyCreate() // GiftWrap is always a random key
-            val sharedSecret = CryptoUtils.getSharedSecretXChaCha(privateKey, recipientPubKey.hexToByteArray())
+            val sharedSecret = CryptoUtils.getSharedSecretNIP24(privateKey, recipientPubKey.hexToByteArray())
 
             val content = gson.toJson(
-                CryptoUtils.encryptXChaCha(
+                CryptoUtils.encryptNIP24(
                     gson.toJson(event),
                     sharedSecret
                 )

app/src/main/java/com/vitorpamplona/amethyst/service/model/LnZapPaymentRequestEvent.kt

@@ -35,9 +35,9 @@ class LnZapPaymentRequestEvent(
         }
 
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecret(privKey, pubkey)
+            val sharedSecret = CryptoUtils.getSharedSecretNIP04(privKey, pubkey)
 
-            val jsonText = CryptoUtils.decrypt(content, sharedSecret)
+            val jsonText = CryptoUtils.decryptNIP04(content, sharedSecret)
 
             val payInvoiceMethod = gson.fromJson(jsonText, Request::class.java)
 
@@ -62,7 +62,7 @@ class LnZapPaymentRequestEvent(
             val pubKey = CryptoUtils.pubkeyCreate(privateKey)
             val serializedRequest = gson.toJson(PayInvoiceMethod.create(lnInvoice))
 
-            val content = CryptoUtils.encrypt(
+            val content = CryptoUtils.encryptNIP04(
                 serializedRequest,
                 privateKey,
                 walletServicePubkey.hexToByteArray()

app/src/main/java/com/vitorpamplona/amethyst/service/model/LnZapPaymentResponseEvent.kt

@@ -30,9 +30,9 @@ class LnZapPaymentResponseEvent(
 
     private fun decrypt(privKey: ByteArray, pubKey: ByteArray): String? {
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecret(privKey, pubKey)
+            val sharedSecret = CryptoUtils.getSharedSecretNIP04(privKey, pubKey)
 
-            val retVal = CryptoUtils.decrypt(content, sharedSecret)
+            val retVal = CryptoUtils.decryptNIP04(content, sharedSecret)
 
             if (retVal.startsWith(PrivateDmEvent.nip18Advertisement)) {
                 retVal.substring(16)

app/src/main/java/com/vitorpamplona/amethyst/service/model/LnZapRequestEvent.kt

@@ -136,7 +136,7 @@ class LnZapRequestEvent(
         }
 
         private fun encryptPrivateZapMessage(msg: String, privkey: ByteArray, pubkey: ByteArray): String {
-            var sharedSecret = CryptoUtils.getSharedSecret(privkey, pubkey)
+            var sharedSecret = CryptoUtils.getSharedSecretNIP04(privkey, pubkey)
             val iv = ByteArray(16)
             SecureRandom().nextBytes(iv)
 
@@ -155,7 +155,7 @@ class LnZapRequestEvent(
         }
 
         private fun decryptPrivateZapMessage(msg: String, privkey: ByteArray, pubkey: ByteArray): String {
-            var sharedSecret = CryptoUtils.getSharedSecret(privkey, pubkey)
+            var sharedSecret = CryptoUtils.getSharedSecretNIP04(privkey, pubkey)
             if (sharedSecret.size != 16 && sharedSecret.size != 32) {
                 throw IllegalArgumentException("Invalid shared secret size")
             }

app/src/main/java/com/vitorpamplona/amethyst/service/model/MuteListEvent.kt

@@ -23,9 +23,9 @@ class MuteListEvent(
 
     fun plainContent(privKey: ByteArray): String? {
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecret(privKey, pubKey.hexToByteArray())
+            val sharedSecret = CryptoUtils.getSharedSecretNIP04(privKey, pubKey.hexToByteArray())
 
-            return CryptoUtils.decrypt(content, sharedSecret)
+            return CryptoUtils.decryptNIP04(content, sharedSecret)
         } catch (e: Exception) {
             Log.w("BookmarkList", "Error decrypting the message ${e.message}")
             null
@@ -87,7 +87,7 @@ class MuteListEvent(
             }
             val msg = gson.toJson(privTags)
 
-            val content = CryptoUtils.encrypt(
+            val content = CryptoUtils.encryptNIP04(
                 msg,
                 privateKey,
                 pubKey

app/src/main/java/com/vitorpamplona/amethyst/service/model/PrivateDmEvent.kt

@@ -55,9 +55,9 @@ class PrivateDmEvent(
 
     fun plainContent(privKey: ByteArray, pubKey: ByteArray): String? {
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecret(privKey, pubKey)
+            val sharedSecret = CryptoUtils.getSharedSecretNIP04(privKey, pubKey)
 
-            val retVal = CryptoUtils.decrypt(content, sharedSecret)
+            val retVal = CryptoUtils.decryptNIP04(content, sharedSecret)
 
             if (retVal.startsWith(nip18Advertisement)) {
                 retVal.substring(16)
@@ -89,7 +89,7 @@ class PrivateDmEvent(
             zapRaiserAmount: Long?,
             geohash: String? = null
         ): PrivateDmEvent {
-            val content = CryptoUtils.encrypt(
+            val content = CryptoUtils.encryptNIP04(
                 if (advertiseNip18) { nip18Advertisement } else { "" } + msg,
                 privateKey,
                 recipientPubKey

app/src/main/java/com/vitorpamplona/amethyst/service/model/SealedGossipEvent.kt

@@ -38,14 +38,14 @@ class SealedGossipEvent(
         if (content.isBlank()) return null
 
         return try {
-            val sharedSecret = CryptoUtils.getSharedSecretXChaCha(privKey, pubKey.hexToByteArray())
+            val sharedSecret = CryptoUtils.getSharedSecretNIP24(privKey, pubKey.hexToByteArray())
 
             val toDecrypt = gson.fromJson<EncryptedInfo>(
                 content,
                 EncryptedInfo::class.java
             )
 
-            return CryptoUtils.decryptXChaCha(toDecrypt, sharedSecret)
+            return CryptoUtils.decryptNIP24(toDecrypt, sharedSecret)
         } catch (e: Exception) {
             Log.w("GeneralList", "Error decrypting the message ${e.message}")
             null
@@ -71,10 +71,10 @@ class SealedGossipEvent(
             privateKey: ByteArray,
             createdAt: Long = TimeUtils.now()
         ): SealedGossipEvent {
-            val sharedSecret = CryptoUtils.getSharedSecretXChaCha(privateKey, encryptTo.hexToByteArray())
+            val sharedSecret = CryptoUtils.getSharedSecretNIP24(privateKey, encryptTo.hexToByteArray())
 
             val content = gson.toJson(
-                CryptoUtils.encryptXChaCha(
+                CryptoUtils.encryptNIP24(
                     gson.toJson(gossip),
                     sharedSecret
                 )

app/src/main/java/com/vitorpamplona/amethyst/service/nip19/Nip19.kt

@@ -5,7 +5,6 @@ import androidx.compose.runtime.Immutable
 import com.vitorpamplona.amethyst.model.hexToByteArray
 import com.vitorpamplona.amethyst.model.toHexKey
 import com.vitorpamplona.amethyst.service.bechToBytes
-import com.vitorpamplona.amethyst.service.toByteArray
 import com.vitorpamplona.amethyst.service.toNEvent
 import java.util.regex.Pattern
 
@@ -170,3 +169,11 @@ object Nip19 {
         return fullArray.toNEvent()
     }
 }
+
+fun Int.toByteArray(): ByteArray {
+    val bytes = ByteArray(4)
+    (0..3).forEach {
+        bytes[3 - it] = ((this ushr (8 * it)) and 0xFFFF).toByte()
+    }
+    return bytes
+}