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#1849 Map enhancements. Adds track list, zoom to selection, history trail size and other features. (#1920)

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Co-authored-by: Dennis Sheirer <dsheirer@github.com>
This commit is contained in:
Denny Sheirer
2024-05-19 07:06:44 -04:00
committed by GitHub
parent c50a914632
commit dddda052fa
14 changed files with 1566 additions and 241 deletions
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103
src/main/java/io/github/dsheirer/module/decode/p25/phase2/timeslot/LinearFeedbackShiftRegister.java
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@@ -1,23 +1,20 @@
/*
* *****************************************************************************
* Copyright (C) 2014-2024 Dennis Sheirer
*
* * ******************************************************************************
* * Copyright (C) 2014-2019 Dennis Sheirer
* *
* * 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 <http://www.gnu.org/licenses/>
* * *****************************************************************************
* 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 <http://www.gnu.org/licenses/>
* ****************************************************************************
*/
package io.github.dsheirer.module.decode.p25.phase2.timeslot;
@@ -63,9 +60,6 @@ public class LinearFeedbackShiftRegister
mSystem = system;
mNac = nac;
int temp = 0xFFFFF & 1;
long tempShift = temp << 24;
mRegisters = (long)(0xFFFFF & wacn) << 24;
mRegisters += (0xFFF & system) << 12;
mRegisters += (0xFFF & nac);
@@ -78,6 +72,16 @@ public class LinearFeedbackShiftRegister
mCurrentOutput = getTap(TAP_43);
}
/**
* Loads the seed value directly into the registers.
* @param seed for the lfsr
*/
public void updateSeed(long seed)
{
mRegisters = seed;
mCurrentOutput = getTap(TAP_43);
}
/**
* Indicates if the shift register is currently configured for the argument values (and doesn't need updating).
*
@@ -120,6 +124,32 @@ public class LinearFeedbackShiftRegister
return sequence;
}
/**
* Generates a (de)scrambling sequence for the specified seed and length
* @param seed value to use
* @param length of the generated sequence
* @return scrambling sequence in a binary message
*/
public BinaryMessage generateScramblingSequence(long seed, int length)
{
updateSeed(seed);
BinaryMessage sequence = new BinaryMessage(length);
try
{
for(int x = 0; x < length; x++)
{
sequence.add(next());
}
}
catch(BitSetFullException e)
{
//This shouldn't happen
}
return sequence;
}
/**
* Provides the next output bit from the LFSR
*/
@@ -152,4 +182,39 @@ public class LinearFeedbackShiftRegister
{
return (mRegisters & tap) == tap;
}
public static void main(String[] args)
{
long seed = 0;
int wacn = 0xBEE00;
int system = 0x1C7;
int nac = 0x1C1;
seed = (long)(0xFFFFF & wacn) << 24;
seed += (0xFFF & system) << 12;
seed += (0xFFF & nac);
seed = 0xBEE001C7013l;
System.out.println("Seed: " + Long.toHexString(seed).toUpperCase());
LinearFeedbackShiftRegister lfsr = new LinearFeedbackShiftRegister();
// BinaryMessage scramble = lfsr.generateScramblingSequence(0xBEE07, 0x40F, 0x04E);
BinaryMessage scramble = lfsr.generateScramblingSequence(seed, 400);
System.out.println("SCRAM: " + scramble.toHexString());
// scramble.rotateRight(64, 0, 401);
System.out.println("SCRAM: " + scramble.toHexString());
BinaryMessage raw1 = BinaryMessage.loadHex("BEE001C70139CB7D5F2D4823695F7ED499EA998F8748E6DAB167FAC15EC2C6222E");
// BinaryMessage raw1 = BinaryMessage.loadHex("BEE0740F04E0172D21681A1B52FFBFBFEE53D2A5ADB9561CADF4D955EBF1CB0000");
// BinaryMessage raw2 = BinaryMessage.loadHex("BEE0740F04E0DD2D21681A1B52FFBFBFEE53FE86BEF78FD5AB910B2376F9D80000");
System.out.println(" RAW: " + raw1.toHexString());
System.out.println(" xxx: BEE001C70139CB");
int length = raw1.length();
raw1.xor(scramble);
BinaryMessage descrambled = raw1.get(0, length);
System.out.println("DESCR: " + descrambled.toHexString());
}
}