implement SPS1 command

I had to add a new dependency: `tink-android:1.5.0` for X25519

core/core_dependencies.gradle

@@ -47,6 +47,7 @@ dependencies {
     //CryptoUtil
     api 'com.madgag.spongycastle:core:1.58.0.0'
 
+
     // Graphview cannot be upgraded
     api "com.jjoe64:graphview:4.0.1"
 

omnipod-dash/build.gradle

@@ -21,7 +21,6 @@ dependencies {
     implementation "androidx.room:room-runtime:$room_version"
     implementation "androidx.room:room-rxjava2:$room_version"
     kapt "androidx.room:room-compiler:$room_version"
-
     implementation 'com.github.guepardoapps:kulid:1.1.2.0'
-
+    implementation 'com.google.crypto.tink:tink-android:1.5.0'
-}
+}

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/OmnipodDashBleManagerImpl.kt

@@ -5,6 +5,7 @@ import android.bluetooth.BluetoothDevice
 import android.bluetooth.BluetoothManager
 import android.bluetooth.BluetoothProfile
 import android.content.Context
+import com.google.crypto.tink.subtle.X25519
 import info.nightscout.androidaps.logging.AAPSLogger
 import info.nightscout.androidaps.logging.LTag
 import info.nightscout.androidaps.plugins.pump.omnipod.dash.BuildConfig
@@ -24,6 +25,7 @@ import org.apache.commons.lang3.NotImplementedException
 import java.util.concurrent.BlockingQueue
 import java.util.concurrent.LinkedBlockingDeque
 import java.util.concurrent.TimeoutException
+import javax.crypto.KeyAgreement
 import javax.inject.Inject
 import javax.inject.Singleton
 

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/command/BleCommand.kt

@@ -1,5 +1,7 @@
 package info.nightscout.androidaps.plugins.pump.omnipod.dash.driver.comm.command
 
+import info.nightscout.androidaps.utils.extensions.toHex
+
 open class BleCommand(val data: ByteArray) {
 
     constructor(type: BleCommandType) : this(byteArrayOf(type.value))
@@ -17,6 +19,10 @@ open class BleCommand(val data: ByteArray) {
         return true
     }
 
+    override fun toString(): String {
+        return "Raw command: [${data.toHex()}]";
+    }
+
     override fun hashCode(): Int {
         return data.contentHashCode()
     }

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/ltk/LTKExchanger.kt

@@ -1,31 +1,41 @@
 package info.nightscout.androidaps.plugins.pump.omnipod.dash.driver.comm.ltk
 
+import com.google.crypto.tink.subtle.X25519
 import info.nightscout.androidaps.logging.AAPSLogger
+import info.nightscout.androidaps.logging.LTag
 import info.nightscout.androidaps.plugins.pump.omnipod.dash.driver.comm.OmnipodDashBleManagerImpl
 import info.nightscout.androidaps.plugins.pump.omnipod.dash.driver.comm.Id
 import info.nightscout.androidaps.plugins.pump.omnipod.dash.driver.comm.message.MessageIO
 import info.nightscout.androidaps.plugins.pump.omnipod.dash.driver.comm.message.StringLengthPrefixEncoding
 import info.nightscout.androidaps.utils.extensions.hexStringToByteArray
+import java.security.SecureRandom
 
 internal class LTKExchanger(private val aapsLogger: AAPSLogger, private val msgIO: MessageIO) {
+    private val privateKey = X25519.generatePrivateKey()
+    private val nonce = ByteArray(16)
+    private val controllerId = Id.fromInt(OmnipodDashBleManagerImpl.CONTROLLER_ID)
+    val nodeId = controllerId.increment()
+    private var seq: Byte = 1
+
+    init{
+        val random = SecureRandom()
+        random.nextBytes(nonce)
+    }
 
     fun negotiateLTKAndNonce(): LTK? {
         // send SP1, SP2
-        // TODO: get this from somewhere(preferences?)
+        var sp1sp2 = sp1sp2(nodeId.address, sp2())
-        var seq: Byte = 1
-        val controllerId = Id.fromInt(OmnipodDashBleManagerImpl.CONTROLLER_ID)
-        val nodeId = controllerId.increment()
-
-        var sp1sp2 = sp1sp2(nodeId.address, sp2(), seq, controllerId, nodeId)
         msgIO.sendMesssage(sp1sp2.messagePacket)
 
-/*
+        seq++
-        var sps1 =
+        var sps1 = sps1()
         msgIO.sendMesssage(sps1.messagePacket)
         // send SPS1
+
         // read SPS1
         val podSps1 = msgIO.receiveMessage()
-
+        aapsLogger.info(LTag.PUMPBTCOMM, "Received message: %s", podSps1)
+/*
         // send SPS2
         var sps2 = PairMessage()
         msgIO.sendMesssage(sps2.messagePacket)
@@ -46,7 +56,7 @@ internal class LTKExchanger(private val aapsLogger: AAPSLogger, private val msgI
         return GET_POD_STATUS_HEX_COMMAND.hexStringToByteArray()
     }
 
-    fun sp1sp2(sp1: ByteArray, sp2: ByteArray, seq: Byte, controllerId: Id, nodeId: Id): PairMessage {
+    fun sp1sp2(sp1: ByteArray, sp2: ByteArray): PairMessage {
         val payload = StringLengthPrefixEncoding.formatKeys(
             arrayOf("SP1=", ",SP2="),
             arrayOf(sp1, sp2),
@@ -59,6 +69,20 @@ internal class LTKExchanger(private val aapsLogger: AAPSLogger, private val msgI
         )
     }
 
+    fun sps1(): PairMessage {
+        val publicKey = X25519.publicFromPrivate(privateKey)
+        val payload = StringLengthPrefixEncoding.formatKeys(
+            arrayOf("SPS1="),
+            arrayOf(publicKey+nonce),
+        )
+        return PairMessage(
+            sequenceNumber = seq,
+            source = controllerId,
+            destination = nodeId,
+            payload = payload,
+        )
+    }
+
     companion object {
 
         private val GET_POD_STATUS_HEX_COMMAND = "ffc32dbd08030e0100008a" // TODO for now we are assuming this command is build out of constant parameters, use a proper command builder for that.

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/message/MessageIO.kt

@@ -38,7 +38,7 @@ class MessageIO(private val aapsLogger: AAPSLogger, private val bleIO: BleIO) {
 
     fun receiveMessage(): MessagePacket {
         val expectRTS = bleIO.receivePacket(CharacteristicType.CMD)
-        if (BleCommand(expectRTS) != BleCommandCTS()) {
+        if (BleCommand(expectRTS) != BleCommandRTS()) {
             throw UnexpectedCommandException(BleCommand(expectRTS))
         }
         bleIO.sendAndConfirmPacket(CharacteristicType.CMD, BleCommandCTS().data)
@@ -53,7 +53,7 @@ class MessageIO(private val aapsLogger: AAPSLogger, private val bleIO: BleIO) {
             }
         }
         if (joiner.oneExtra) {
-            var data = bleIO.receivePacket(CharacteristicType.DATA)
+            data = bleIO.receivePacket(CharacteristicType.DATA)
             val accumulateAction = joiner.accumulate(data)
             if (accumulateAction is PayloadJoinerActionReject) {
                 bleIO.sendAndConfirmPacket(CharacteristicType.CMD, BleCommandNack(accumulateAction.idx).data)

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/message/PayloadSplitter.kt

@@ -25,6 +25,7 @@ internal class PayloadSplitter(private val payload: ByteArray) {
                 ret.add(LastOptionalPlusOneBlePacket(
                     index = 1,
                     payload = payload.copyOfRange(end, payload.size),
+                    size = (payload.size-end).toByte(),
                 ))
             }
             return ret
@@ -53,9 +54,10 @@ internal class PayloadSplitter(private val payload: ByteArray) {
             payload = payload.copyOfRange(middleFragments * MiddleBlePacket.CAPACITY + FirstBlePacket.CAPACITY_WITH_MIDDLE_PACKETS, middleFragments * MiddleBlePacket.CAPACITY + FirstBlePacket.CAPACITY_WITH_MIDDLE_PACKETS + end),
             crc32 = crc32,
         ))
-        if (rest > 14) {
+        if (rest > LastBlePacket.CAPACITY) {
             ret.add(LastOptionalPlusOneBlePacket(
                 index = (middleFragments + 2).toByte(),
+                size = (rest-LastBlePacket.CAPACITY).toByte(),
                 payload = payload.copyOfRange(middleFragments * MiddleBlePacket.CAPACITY + FirstBlePacket.CAPACITY_WITH_MIDDLE_PACKETS + LastBlePacket.CAPACITY, payload.size),
             ))
         }

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/packet/BlePacket.kt

@@ -7,6 +7,7 @@ sealed class BlePacket {
     abstract fun asByteArray(): ByteArray
 
     companion object {
+
         const val MAX_BLE_PACKET_LEN = 20
         const val MAX_BLE_BUFFER_LEN = MAX_BLE_PACKET_LEN + 1 // we use this as the size allocated for the ByteBuffer
     }
@@ -33,6 +34,7 @@ data class FirstBlePacket(val totalFragments: Byte, val payload: ByteArray, val
     }
 
     companion object {
+
         internal const val CAPACITY_WITHOUT_MIDDLE_PACKETS = 13 // we are using all fields
         internal const val CAPACITY_WITH_MIDDLE_PACKETS = 18 // we are not using crc32 or size
         internal const val CAPACITY_WITH_THE_OPTIONAL_PLUS_ONE_PACKET = 18
@@ -46,6 +48,7 @@ data class MiddleBlePacket(val index: Byte, val payload: ByteArray) : BlePacket(
     }
 
     companion object {
+
         internal const val CAPACITY = 19
     }
 }
@@ -66,14 +69,15 @@ data class LastBlePacket(val index: Byte, val size: Byte, val payload: ByteArray
     }
 
     companion object {
+
         internal const val CAPACITY = 14
     }
 }
 
-data class LastOptionalPlusOneBlePacket(val index: Byte, val payload: ByteArray) : BlePacket() {
+data class LastOptionalPlusOneBlePacket(val index: Byte, val payload: ByteArray, val size: Byte) : BlePacket() {
 
     override fun asByteArray(): ByteArray {
-        return byteArrayOf(index) + payload
+        return byteArrayOf(index, size) + payload
     }
 }
 

omnipod-dash/src/main/java/info/nightscout/androidaps/plugins/pump/omnipod/dash/driver/comm/scan/BleDiscoveredDevice.kt

@@ -31,7 +31,6 @@ class BleDiscoveredDevice(val scanResult: ScanResult, private val scanRecord: Sc
     @Throws(DiscoveredInvalidPodException::class)
 
     private fun validatePodId() {
-        val scanRecord = scanResult.scanRecord
         val serviceUUIDs = scanRecord.serviceUuids
         val hexPodId = extractUUID16(serviceUUIDs[3]) + extractUUID16(serviceUUIDs[4])
         val podId = hexPodId.toLong(16)