P25-P2 Encryption Synchronization ReSync (#1792)

* resync ess processor on PTT, END_PTT, HANGTIME, or IDLE * Re-order of AbstractVoiceTimeslot. Voice2 should be processed first, as any accumulated ESS information applies to the following Voice slots * Update P25 MBE recorders to include synchronized encryption information --------- Co-authored-by: Sawyer, Caleb (US) - ISR <Caleb.Sawyer@L3Harris.com>
DSheirer · Jan 12, 2024 · 3c18bfd · 3c18bfd
1 parent d89ba65
commit 3c18bfd
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Showing 3 changed files with 61 additions and 2 deletions.
diff --git a/src/main/java/io/github/dsheirer/module/decode/p25/audio/P25P1CallSequenceRecorder.java b/src/main/java/io/github/dsheirer/module/decode/p25/audio/P25P1CallSequenceRecorder.java
@@ -25,6 +25,9 @@
 import io.github.dsheirer.bits.BinaryMessage;
 import io.github.dsheirer.message.IMessage;
 import io.github.dsheirer.module.decode.p25.phase1.message.P25Message;
+import io.github.dsheirer.module.decode.p25.phase1.message.hdu.HDUMessage;
+import io.github.dsheirer.module.decode.p25.phase1.message.hdu.HeaderData;
+import io.github.dsheirer.identifier.encryption.EncryptionKeyIdentifier;
 import io.github.dsheirer.module.decode.p25.phase1.message.lc.LinkControlWord;
 import io.github.dsheirer.module.decode.p25.phase1.message.lc.motorola.LCMotorolaPatchGroupVoiceChannelUpdate;
 import io.github.dsheirer.module.decode.p25.phase1.message.lc.motorola.LCMotorolaPatchGroupVoiceChannelUser;
@@ -124,6 +127,10 @@ else if(message instanceof TDUMessage)
         {
             flush();
         }
+        else if (message instanceof HDUMessage)
+        {
+            process((HDUMessage)message);
+        }
     }
 
     private void process(TDULinkControlMessage tdulc)
@@ -228,4 +235,21 @@ private void process(LDU2Message ldu2Message)
             mCallSequence.setEncryptionSyncParameters(parameters);
         }
     }
+
+    private void process(HDUMessage hduMessage)
+    {
+        if(mCallSequence == null)
+        {
+            mCallSequence = new MBECallSequence(PROTOCOL);
+        }
+
+        HeaderData hd = hduMessage.getHeaderData();
+
+        if (hd.isEncryptedAudio())
+        {
+            mCallSequence.setEncrypted(true);
+            Phase2EncryptionSyncParameters esp = new Phase2EncryptionSyncParameters((EncryptionKeyIdentifier)hd.getEncryptionKey(), hd.getMessageIndicator());
+            mCallSequence.setEncryptionSyncParameters(esp);
+        }
+    }
 }
diff --git a/src/main/java/io/github/dsheirer/module/decode/p25/audio/P25P2CallSequenceRecorder.java b/src/main/java/io/github/dsheirer/module/decode/p25/audio/P25P2CallSequenceRecorder.java
@@ -27,6 +27,7 @@
 import io.github.dsheirer.audio.codec.mbe.MBECallSequenceRecorder;
 import io.github.dsheirer.bits.BinaryMessage;
 import io.github.dsheirer.message.IMessage;
+import io.github.dsheirer.module.decode.p25.phase2.message.EncryptionSynchronizationSequence;
 import io.github.dsheirer.module.decode.p25.phase2.message.P25P2Message;
 import io.github.dsheirer.module.decode.p25.phase2.message.mac.MacMessage;
 import io.github.dsheirer.module.decode.p25.phase2.message.mac.MacStructure;
@@ -153,6 +154,10 @@ else if(message instanceof MacMessage)
             {
                 process((MacMessage)message);
             }
+            else if (message instanceof EncryptionSynchronizationSequence)
+            {
+                processEss((EncryptionSynchronizationSequence)message);
+            }
         }
 
         /**
@@ -382,5 +387,18 @@ private void processPTT(MacStructure mac) {
                 mLog.warn("Expected push-to-talk structure but found: " + mac.getClass());
             }
         }
+
+        private void processEss(EncryptionSynchronizationSequence ess)
+        {
+            if(mCallSequence == null)
+            {
+                mCallSequence = new MBECallSequence(PROTOCOL);
+            }
+            if (ess.isEncrypted())
+            {
+                mCallSequence.setEncrypted(true);
+                mCallSequence.setEncryptionSyncParameters(ess);
+            }
+        }
     }
 }
diff --git a/src/main/java/io/github/dsheirer/module/decode/p25/phase2/P25P2MessageProcessor.java b/src/main/java/io/github/dsheirer/module/decode/p25/phase2/P25P2MessageProcessor.java
@@ -101,11 +101,30 @@ public void receive(IMessage message)
                                 mFrequencyBandMap.put(bandIdentifier.getIdentifier(), bandIdentifier);
                             }
 
+                            switch(macMessage.getMacPduType())
+                            {
+                                case MAC_1_PTT:
+                                case MAC_2_END_PTT:
+                                case MAC_6_HANGTIME:
+                                case MAC_3_IDLE:
+                                    if (timeslot.getTimeslot() == 0)
+                                    {
+                                        mESSProcessor0.reset();
+                                    }
+                                    else
+                                    {
+                                        mESSProcessor1.reset();
+                                    }
+                                    break;
+                            }
+
                             mMessageListener.receive(macMessage);
                         }
                     }
                     else if(timeslot instanceof AbstractVoiceTimeslot)
                     {
+                        mMessageListener.receive(timeslot);
+
                         if(timeslot.getTimeslot() == 0)
                         {
                             mESSProcessor0.process((AbstractVoiceTimeslot)timeslot);
@@ -139,8 +158,6 @@ else if(timeslot instanceof AbstractVoiceTimeslot)
                             }
                         }
 
-                        mMessageListener.receive(timeslot);
-
                     }
                     else
                     {