diff --git a/app/src/main/java/info/nightscout/android/medtronic/GetHmacAndKeyActivity.java b/app/src/main/java/info/nightscout/android/medtronic/GetHmacAndKeyActivity.java
index 64c30b3aea050802499e70eac5b49b00e373fbea..f283f844fbee0a6529dfaa5ab52e549bec048f92 100644
--- a/app/src/main/java/info/nightscout/android/medtronic/GetHmacAndKeyActivity.java
+++ b/app/src/main/java/info/nightscout/android/medtronic/GetHmacAndKeyActivity.java
@@ -340,7 +340,6 @@ public class GetHmacAndKeyActivity extends AppCompatActivity implements LoaderCa
String key = MessageUtils.byteArrayToHexString((byte[]) keyResponse.readObject());
realm.beginTransaction();
- info.setHmac(hmac);
info.setKey(key);
realm.commitTransaction();
}
diff --git a/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlReader.java b/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlReader.java
index f4aeb0c90953398ab78394ea7f1600430657958b..6dd908f0dd3f57b8d8c585d51690eaee4b82df5b 100644
--- a/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlReader.java
+++ b/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlReader.java
@@ -9,6 +9,7 @@ import java.io.IOException;
import java.math.BigDecimal;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
+import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
@@ -36,6 +37,7 @@ import info.nightscout.android.medtronic.message.PumpStatusResponseMessage;
import info.nightscout.android.medtronic.message.PumpTimeRequestMessage;
import info.nightscout.android.medtronic.message.PumpTimeResponseMessage;
import info.nightscout.android.medtronic.message.ReadInfoResponseMessage;
+import info.nightscout.android.medtronic.message.RequestLinkKeyResponseMessage;
import info.nightscout.android.medtronic.message.UnexpectedMessageException;
import info.nightscout.android.model.medtronicNg.PumpStatusEvent;
import info.nightscout.android.utils.HexDump;
@@ -238,7 +240,7 @@ public class MedtronicCnlReader implements ContourNextLinkMessageHandler {
Log.d(TAG, "Finished enterPasshtroughMode");
}
- public void openConnection() throws IOException, TimeoutException {
+ public void openConnection() throws IOException, TimeoutException, NoSuchAlgorithmException {
Log.d(TAG, "Begin openConnection");
new ContourNextLinkBinaryMessage(ContourNextLinkBinaryMessage.CommandType.OPEN_CONNECTION, mPumpSession, mPumpSession.getHMAC()).send(this);
// FIXME - We need to care what the response message is - wrong MAC and all that
@@ -264,6 +266,24 @@ public class MedtronicCnlReader implements ContourNextLinkMessageHandler {
Log.d(TAG, String.format("Finished requestReadInfo. linkMAC = '%d', pumpMAC = '%d", linkMAC, pumpMAC));
}
+ public void requestLinkKey() throws IOException, TimeoutException, EncryptionException, ChecksumException {
+ Log.d(TAG, "Begin requestLinkKey");
+ new ContourNextLinkBinaryMessage(ContourNextLinkBinaryMessage.CommandType.REQUEST_LINK_KEY, mPumpSession, null).send(this);
+
+ ContourNextLinkMessage response = RequestLinkKeyResponseMessage.fromBytes(mPumpSession, readMessage());
+
+ // FIXME - this needs to go into RequestLinkKeyResponseMessage
+ ByteBuffer infoBuffer = ByteBuffer.allocate(55);
+ infoBuffer.order(ByteOrder.BIG_ENDIAN);
+ infoBuffer.put(response.encode(), 0x21, 55);
+
+ byte[] packedLinkKey = infoBuffer.array();
+
+ this.getPumpSession().setPackedLinkKey(packedLinkKey);
+
+ Log.d(TAG, String.format("Finished requestLinkKey. linkKey = '%s'", this.getPumpSession().getKey()));
+ }
+
public byte negotiateChannel(byte lastRadioChannel) throws IOException, ChecksumException, TimeoutException {
ArrayList<Byte> radioChannels = new ArrayList<>(Arrays.asList(ArrayUtils.toObject(RADIO_CHANNELS)));
diff --git a/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlSession.java b/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlSession.java
index 0f22dd79dc7950f50849f69d7397288e900a7181..215e7f3e6174163da35db8824c928d87f5d454bb 100644
--- a/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlSession.java
+++ b/app/src/main/java/info/nightscout/android/medtronic/MedtronicCnlSession.java
@@ -1,12 +1,21 @@
package info.nightscout.android.medtronic;
+import org.apache.commons.lang3.ArrayUtils;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
/**
* Created by lgoedhart on 26/03/2016.
*/
public class MedtronicCnlSession {
+ private static final String HMAC_PADDING = "A4BD6CED9A42602564F413123";
+
private byte[] HMAC;
private byte[] key;
+ private String stickSerial;
+
private long linkMAC;
private long pumpMAC;
@@ -14,16 +23,31 @@ public class MedtronicCnlSession {
private int bayerSequenceNumber = 1;
private int medtronicSequenceNumber = 1;
- public byte[] getHMAC() {
+ /*public byte[] getHMAC() {
return HMAC;
+ }*/
+
+ public byte[] getHMAC() throws NoSuchAlgorithmException {
+ String shortSerial = this.stickSerial.replaceAll("\\d+-", "");
+ byte[] message = (shortSerial + HMAC_PADDING).getBytes();
+ byte[] numArray;
+
+ MessageDigest instance = MessageDigest.getInstance("SHA-256");
+ instance.update(message);
+
+ numArray = instance.digest();
+ ArrayUtils.reverse(numArray);
+
+ return numArray;
}
public byte[] getKey() {
return key;
}
+
public byte[] getIV() {
byte[] iv = new byte[key.length];
- System.arraycopy(key,0,iv,0,key.length);
+ System.arraycopy(key, 0, iv, 0, key.length);
iv[0] = radioChannel;
return iv;
}
@@ -32,7 +56,7 @@ public class MedtronicCnlSession {
return linkMAC;
}
- public void setLinkMAC( long linkMAC ) {
+ public void setLinkMAC(long linkMAC) {
this.linkMAC = linkMAC;
}
@@ -40,7 +64,7 @@ public class MedtronicCnlSession {
return pumpMAC;
}
- public void setPumpMAC( long pumpMAC ) {
+ public void setPumpMAC(long pumpMAC) {
this.pumpMAC = pumpMAC;
}
@@ -68,11 +92,39 @@ public class MedtronicCnlSession {
this.radioChannel = radioChannel;
}
- public void setHMAC( byte[] hmac ) {
+ public void setHMAC(byte[] hmac) {
this.HMAC = hmac;
}
- public void setKey( byte[] key ) {
+ public void setKey(byte[] key) {
this.key = key;
}
+
+ public void setPackedLinkKey(byte[] packedLinkKey) {
+ this.key = new byte[16];
+
+ int pos = this.stickSerial.charAt(this.stickSerial.length() - 1) & 7;
+
+ for (int i = 0; i < this.key.length; i++) {
+ if ((packedLinkKey[pos + 1] & 1) == 1) {
+ this.key[i] = (byte) ~packedLinkKey[pos];
+ } else {
+ this.key[i] = packedLinkKey[pos];
+ }
+
+ if (((packedLinkKey[pos + 1] >> 1) & 1) == 0) {
+ pos += 3;
+ } else {
+ pos += 2;
+ }
+ }
+ }
+
+ public String getStickSerial() {
+ return stickSerial;
+ }
+
+ public void setStickSerial(String stickSerial) {
+ this.stickSerial = stickSerial;
+ }
}
diff --git a/app/src/main/java/info/nightscout/android/medtronic/message/ContourNextLinkBinaryMessage.java b/app/src/main/java/info/nightscout/android/medtronic/message/ContourNextLinkBinaryMessage.java
index c5b8107a3c4c7aed1fd091f0312e8a51e76b3297..95e94baa56ef73718e3db0d2d13e272f8b48a058 100644
--- a/app/src/main/java/info/nightscout/android/medtronic/message/ContourNextLinkBinaryMessage.java
+++ b/app/src/main/java/info/nightscout/android/medtronic/message/ContourNextLinkBinaryMessage.java
@@ -34,6 +34,10 @@ public class ContourNextLinkBinaryMessage extends ContourNextLinkMessage{
CommandType(int commandType) {
value = (byte) commandType;
}
+
+ public int getValue() {
+ return value;
+ }
}
public ContourNextLinkBinaryMessage(CommandType commandType, MedtronicCnlSession pumpSession, byte[] payload) {
diff --git a/app/src/main/java/info/nightscout/android/medtronic/message/MedtronicReceiveMessage.java b/app/src/main/java/info/nightscout/android/medtronic/message/MedtronicReceiveMessage.java
index 28dd3a5e76d16ea819f742f6487d0ff563c7fef9..c2f4a7d58cf10d70925e3d2ab15e3358a4ff3a3f 100644
--- a/app/src/main/java/info/nightscout/android/medtronic/message/MedtronicReceiveMessage.java
+++ b/app/src/main/java/info/nightscout/android/medtronic/message/MedtronicReceiveMessage.java
@@ -45,7 +45,10 @@ public class MedtronicReceiveMessage extends MedtronicMessage {
// TODO - Validate the message, inner CCITT, serial numbers, etc
// If there's not 57 bytes, then we got back a bad message. Not sure how to process these yet.
- if( bytes.length >= 57 ) {
+ // Also, READ_INFO and REQUEST_LINK_KEY are not encrypted
+ if (bytes.length >= 57 &&
+ (bytes[18] != CommandType.READ_INFO.getValue()) &&
+ (bytes[18] != CommandType.REQUEST_LINK_KEY_RESPONSE.getValue())) {
// Replace the encrypted bytes by their decrypted equivalent (same block size)
byte encryptedPayloadSize = bytes[56];
diff --git a/app/src/main/java/info/nightscout/android/medtronic/message/RequestLinkKeyResponseMessage.java b/app/src/main/java/info/nightscout/android/medtronic/message/RequestLinkKeyResponseMessage.java
new file mode 100644
index 0000000000000000000000000000000000000000..423e40fb8ab61296fc9c26995837a56932715a7e
--- /dev/null
+++ b/app/src/main/java/info/nightscout/android/medtronic/message/RequestLinkKeyResponseMessage.java
@@ -0,0 +1,21 @@
+package info.nightscout.android.medtronic.message;
+
+import info.nightscout.android.medtronic.MedtronicCnlSession;
+
+/**
+ * Created by lgoedhart on 10/05/2016.
+ */
+public class RequestLinkKeyResponseMessage extends MedtronicReceiveMessage {
+ protected RequestLinkKeyResponseMessage(CommandType commandType, CommandAction commandAction, MedtronicCnlSession pumpSession, byte[] payload) {
+ super(commandType, commandAction, pumpSession, payload);
+ }
+
+ public static ContourNextLinkMessage fromBytes(MedtronicCnlSession pumpSession, byte[] bytes) throws ChecksumException, EncryptionException {
+ // TODO - turn this into a factory
+ ContourNextLinkMessage message = MedtronicReceiveMessage.fromBytes(pumpSession, bytes);
+
+ // TODO - Validate the MessageType
+
+ return message;
+ }
+}
\ No newline at end of file
diff --git a/app/src/main/java/info/nightscout/android/medtronic/service/MedtronicCnlIntentService.java b/app/src/main/java/info/nightscout/android/medtronic/service/MedtronicCnlIntentService.java
index 5a403aa65172fda96de03c2d04022b18acec924d..814f29de870282cf6b54da5c6619dbbadc4f6864 100644
--- a/app/src/main/java/info/nightscout/android/medtronic/service/MedtronicCnlIntentService.java
+++ b/app/src/main/java/info/nightscout/android/medtronic/service/MedtronicCnlIntentService.java
@@ -16,6 +16,7 @@ import android.support.v4.content.LocalBroadcastManager;
import android.util.Log;
import java.io.IOException;
+import java.security.NoSuchAlgorithmException;
import java.util.Date;
import java.util.Locale;
import java.util.concurrent.TimeoutException;
@@ -157,6 +158,9 @@ public class MedtronicCnlIntentService extends IntentService {
info = realm.copyToRealm(info);
}
+ cnlReader.getPumpSession().setStickSerial(info.getSerialNumber());
+
+ /*
String hmac = info.getHmac();
String key = info.getKey();
@@ -173,6 +177,7 @@ public class MedtronicCnlIntentService extends IntentService {
cnlReader.getPumpSession().setHMAC(MessageUtils.hexStringToByteArray(hmac));
cnlReader.getPumpSession().setKey(MessageUtils.hexStringToByteArray(key));
+ */
cnlReader.enterControlMode();
@@ -181,6 +186,17 @@ public class MedtronicCnlIntentService extends IntentService {
cnlReader.openConnection();
cnlReader.requestReadInfo();
+ String key = info.getKey();
+
+ if (key == null) {
+ cnlReader.requestLinkKey();
+
+ info.setKey(MessageUtils.byteArrayToHexString(cnlReader.getPumpSession().getKey()));
+ key = info.getKey();
+ }
+
+ cnlReader.getPumpSession().setKey(MessageUtils.hexStringToByteArray(key));
+
long pumpMAC = cnlReader.getPumpSession().getPumpMAC();
Log.i(TAG, "PumpInfo MAC: " + (pumpMAC & 0xffffff));
MainActivity.setActivePumpMac(pumpMAC);
@@ -250,6 +266,9 @@ public class MedtronicCnlIntentService extends IntentService {
} catch (UnexpectedMessageException e) {
Log.e(TAG, "Unexpected Message", e);
sendStatus("Communication Error: " + e.getMessage());
+ } catch (NoSuchAlgorithmException e) {
+ Log.e(TAG, "Could not determine CNL HMAC", e);
+ sendStatus("Error connecting to Contour Next Link: Hashing error.");
} finally {
//TODO : 05.11.2016 has the close to be here?
cnlReader.closeConnection();
@@ -304,7 +323,7 @@ public class MedtronicCnlIntentService extends IntentService {
final Intent receiverIntent = new Intent(this, XDripPlusUploadReceiver.class);
final long timestamp = System.currentTimeMillis() + 500L;
final PendingIntent pendingIntent = PendingIntent.getBroadcast(this, (int) timestamp, receiverIntent, PendingIntent.FLAG_ONE_SHOT);
- Log.d(TAG,"Scheduling xDrip+ send");
+ Log.d(TAG, "Scheduling xDrip+ send");
wakeUpIntent(getApplicationContext(), timestamp, pendingIntent);
}
}
@@ -312,7 +331,7 @@ public class MedtronicCnlIntentService extends IntentService {
private void uploadToNightscout() {
Intent receiverIntent = new Intent(this, NightscoutUploadReceiver.class);
final long timestamp = System.currentTimeMillis() + 1000L;
- final PendingIntent pendingIntent = PendingIntent.getBroadcast(this, (int)timestamp, receiverIntent, PendingIntent.FLAG_ONE_SHOT);
+ final PendingIntent pendingIntent = PendingIntent.getBroadcast(this, (int) timestamp, receiverIntent, PendingIntent.FLAG_ONE_SHOT);
wakeUpIntent(getApplicationContext(), timestamp, pendingIntent);
}
diff --git a/app/src/main/java/info/nightscout/android/model/medtronicNg/ContourNextLinkInfo.java b/app/src/main/java/info/nightscout/android/model/medtronicNg/ContourNextLinkInfo.java
index 404d801c8250aaa33c13ca53e58b0d9f0e852a05..9b054671a3580a5c5e142405e89d8ea52147e100 100644
--- a/app/src/main/java/info/nightscout/android/model/medtronicNg/ContourNextLinkInfo.java
+++ b/app/src/main/java/info/nightscout/android/model/medtronicNg/ContourNextLinkInfo.java
@@ -9,7 +9,6 @@ import io.realm.annotations.PrimaryKey;
public class ContourNextLinkInfo extends RealmObject {
@PrimaryKey
private String serialNumber;
- private String hmac;
private String key;
public String getSerialNumber() {
@@ -20,14 +19,6 @@ public class ContourNextLinkInfo extends RealmObject {
this.serialNumber = serialNumber;
}
- public String getHmac() {
- return hmac;
- }
-
- public void setHmac(String hmac) {
- this.hmac = hmac;
- }
-
public String getKey() {
return key;
}