wip MessageSigner3

src/main/java/de/bixilon/minosoft/data/chat/signature/MessageChain.kt

@@ -15,13 +15,14 @@ package de.bixilon.minosoft.data.chat.signature
 
 import de.bixilon.minosoft.data.chat.signature.signer.MessageSigner
 import de.bixilon.minosoft.data.text.ChatComponent
+import de.bixilon.minosoft.protocol.network.connection.play.PlayConnection
 import de.bixilon.minosoft.protocol.versions.Version
 import java.security.PrivateKey
 import java.time.Instant
 import java.util.*
 
-class MessageChain(version: Version) {
+class MessageChain(version: Version, connection: PlayConnection) {
-    val signer = MessageSigner.forVersion(version)
+    val signer = MessageSigner.forVersion(version, connection)
 
     fun signMessage(privateKey: PrivateKey, message: String, preview: ChatComponent?, salt: Long, sender: UUID, time: Instant, lastSeen: LastSeenMessageList): ByteArray {
         return signer.signMessage(privateKey, message, preview, salt, sender, time, lastSeen)

src/main/java/de/bixilon/minosoft/data/chat/signature/MessageLink.kt

@@ -0,0 +1,28 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * 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 <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.data.chat.signature
+
+import java.util.*
+
+class MessageLink(
+    val index: Int,
+    val sender: UUID,
+    val sessionId: UUID,
+) {
+
+    fun next(): MessageLink {
+        // TODO: check Int.MAX_VALUE
+        return MessageLink(index + 1, sender, sessionId)
+    }
+}

src/main/java/de/bixilon/minosoft/data/chat/signature/errors/MessageExpiredError.kt

@@ -1,6 +1,6 @@
 /*
  * Minosoft
- * Copyright (C) 2020-2022 Moritz Zwerger
+ * Copyright (C) 2020-2023 Moritz Zwerger
  *
  * 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.
  *
@@ -18,4 +18,4 @@ import java.time.Instant
 class MessageExpiredError(
     val sent: Instant,
     val received: Instant,
-) : Exception("Message expired: Sent at $sent, but received to late at $received")
+) : Exception("Message expired: Sent at $sent, but received too late at $received")

src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner.kt

@@ -15,6 +15,7 @@ package de.bixilon.minosoft.data.chat.signature.signer
 
 import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
 import de.bixilon.minosoft.data.text.ChatComponent
+import de.bixilon.minosoft.protocol.network.connection.play.PlayConnection
 import de.bixilon.minosoft.protocol.protocol.ProtocolVersions
 import de.bixilon.minosoft.protocol.versions.Version
 import java.security.PrivateKey
@@ -28,14 +29,14 @@ interface MessageSigner {
 
     companion object {
 
-        fun forVersion(version: Version): MessageSigner {
+        fun forVersion(version: Version, connection: PlayConnection): MessageSigner {
             if (version < ProtocolVersions.V_1_19_1_PRE4) {
                 return MessageSigner1(version)
             }
             if (version < ProtocolVersions.V_22W42A) {
                 return MessageSigner2(version)
             }
-            return MessageSigner3(version)
+            return MessageSigner3(version, connection)
         }
     }
 }

src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner2.kt

@@ -14,9 +14,9 @@
 package de.bixilon.minosoft.data.chat.signature.signer
 
 import com.google.common.hash.Hashing
-import com.google.common.primitives.Longs
 import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
 import de.bixilon.minosoft.data.chat.signature.signer.MessageSigningUtil.getSignatureBytes
+import de.bixilon.minosoft.data.chat.signature.signer.MessageSigningUtil.update
 import de.bixilon.minosoft.data.text.ChatComponent
 import de.bixilon.minosoft.protocol.protocol.OutByteBuffer
 import de.bixilon.minosoft.protocol.protocol.ProtocolVersions
@@ -59,8 +59,7 @@ class MessageSigner2(
         val hash = Hashing.sha256().hashBytes(buffer.toArray()).asBytes()
 
         previous?.let { signature.update(it) }
-        signature.update(Longs.toByteArray(sender.mostSignificantBits))
+        signature.update(sender)
-        signature.update(Longs.toByteArray(sender.leastSignificantBits))
         signature.update(hash)
 
         return signature.sign()

src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3.kt

@@ -13,8 +13,15 @@
 
 package de.bixilon.minosoft.data.chat.signature.signer
 
+import com.google.common.primitives.Ints
+import com.google.common.primitives.Longs
 import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
+import de.bixilon.minosoft.data.chat.signature.MessageLink
+import de.bixilon.minosoft.data.chat.signature.signer.MessageSigningUtil.update
 import de.bixilon.minosoft.data.text.ChatComponent
+import de.bixilon.minosoft.protocol.ProtocolUtil.encodeNetwork
+import de.bixilon.minosoft.protocol.network.connection.play.PlayConnection
+import de.bixilon.minosoft.protocol.protocol.encryption.CryptManager
 import de.bixilon.minosoft.protocol.versions.Version
 import java.security.PrivateKey
 import java.time.Instant
@@ -22,9 +29,41 @@ import java.util.*
 
 class MessageSigner3(
     private val version: Version,
+    private val connection: PlayConnection,
 ) : MessageSigner {
+    private var link: MessageLink = MessageLink(0, connection.account.uuid, connection.sessionId)
 
     override fun signMessage(privateKey: PrivateKey, message: String, preview: ChatComponent?, salt: Long, sender: UUID, time: Instant, lastSeen: LastSeenMessageList): ByteArray {
-        TODO("Not yet implemented!")
+        val signature = CryptManager.createSignature(version)
+
+        signature.initSign(privateKey)
+
+        signature.update(Ints.toByteArray(1))
+
+        val link = nextLink()
+        signature.update(link.sender)
+        signature.update(link.sessionId)
+        signature.update(Ints.toByteArray(link.index))
+
+        // message body
+        signature.update(Longs.toByteArray(salt))
+        signature.update(Longs.toByteArray(time.epochSecond))
+        val encoded = message.encodeNetwork()
+        signature.update(Ints.toByteArray(encoded.size))
+        signature.update(encoded)
+
+        signature.update(Ints.toByteArray(lastSeen.messages.size))
+
+        for (lastSeenMessage in lastSeen.messages) {
+            signature.update(lastSeenMessage.signature)
+        }
+
+
+        return signature.sign()
+    }
+
+    private fun nextLink(): MessageLink {
+        this.link = this.link.next()
+        return this.link
     }
 }

src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigningUtil.kt

@@ -14,11 +14,19 @@
 package de.bixilon.minosoft.data.chat.signature.signer
 
 import com.fasterxml.jackson.core.io.JsonStringEncoder
+import com.google.common.primitives.Longs
 import de.bixilon.minosoft.protocol.ProtocolUtil.encodeNetwork
+import java.security.Signature
+import java.util.*
 
 object MessageSigningUtil {
 
     fun String.getSignatureBytes(): ByteArray {
         return """{"text":"${String(JsonStringEncoder.getInstance().quoteAsString(this))}"}""".encodeNetwork()
     }
+
+    fun Signature.update(uuid: UUID) {
+        update(Longs.toByteArray(uuid.mostSignificantBits))
+        update(Longs.toByteArray(uuid.leastSignificantBits))
+    }
 }

src/main/java/de/bixilon/minosoft/protocol/network/connection/play/ConnectionUtil.kt

@@ -47,7 +47,7 @@ import java.time.Instant
 class ConnectionUtil(
     private val connection: PlayConnection,
 ) {
-    private val chain = MessageChain(connection.version)
+    private val chain = MessageChain(connection.version, connection)
     private val random = SecureRandom()
 
     fun sendDebugMessage(message: Any) {