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#1304 P25 Phase 1/2 decoder enhancements. (#1898)

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* P25 Phase 2 now supports control channel decoding and decoder was enhanced to improve decodes.
* Radio reference site editor updated for phase 2 sites to allow user to select FDMA or TDMA control.
* Decode events are now minimized and de-duplicated.
* Fully parsing all phase 1/2 messages from the latest ICD.
* Vendor specific messaging recoveries (Moto & Harris).
* Patch group management enhancements with stale patch detection.
* Tuner editor now fully resets the min/max frequency values
* Default traffic channel count increased to 20 (from 3).
* ISSI roaming radio and talkgroup values now displayed and aliasable as fully qualified values (e.g. 1234(123.456.7890)
* Moto emergency alarm activation messaging support
* Expanded list of P25 encryption algorithms
* Message (bits) viewer enhanced for P25 phase 1 and phase 2
* IPV4 addresses and UDP ports no longer classified as user values - won't display in event views.
* New framework for describing message binary fields that should reduce overall memory footprint and enhance code readability

Co-authored-by: Dennis Sheirer <dsheirer@github.com>
This commit is contained in:
Denny Sheirer
2024-04-26 13:55:17 -04:00
committed by GitHub
parent f5938fa8e2
commit 7e709d9d6f
430 changed files with 30098 additions and 13300 deletions
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49
src/main/java/io/github/dsheirer/edac/CRCUtil.java
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@@ -1,6 +1,6 @@
/*
* *****************************************************************************
* Copyright (C) 2014-2023 Dennis Sheirer
* Copyright (C) 2014-2024 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
@@ -19,6 +19,7 @@
package io.github.dsheirer.edac;
import io.github.dsheirer.bits.BinaryMessage;
import io.github.dsheirer.bits.CorrectedBinaryMessage;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@@ -32,8 +33,7 @@ public class CRCUtil
long initialFill,
boolean includeCRCBitErrors)
{
long[] crcTable = new long[messageSize +
(includeCRCBitErrors ? crcSize : 0)];
long[] crcTable = new long[messageSize + (includeCRCBitErrors ? crcSize : 0)];
int[] checksumIndexes = new int[crcSize];
@@ -132,20 +132,12 @@ public class CRCUtil
* @return message with all message bits zeroed out, and the remainder
* placed in the crc field which starts at index messageLength
*/
public static BinaryMessage decode(BinaryMessage message,
int messageStart,
int messageSize,
long polynomial,
int crcSize)
public static BinaryMessage decode(BinaryMessage message, int messageStart, int messageSize, long polynomial, int crcSize)
{
for(int i = message.nextSetBit(messageStart);
i >= messageStart && i < messageSize;
i = message.nextSetBit(i + 1))
for(int i = message.nextSetBit(messageStart); i >= messageStart && i < messageSize; i = message.nextSetBit(i + 1))
{
BinaryMessage polySet = new BinaryMessage(crcSize + i + 1);
polySet.load(i, crcSize + 1, polynomial);
message.xor(polySet);
System.out.println(message.toString());
}
@@ -226,8 +218,11 @@ public class CRCUtil
{
mLog.debug("Starting");
long poly = 0x13l;
long[] checksums = generate(32, 4, poly, 0, true);
int messageSize = 164;
int crcSize = 16;
long poly = 0x11021l;
long initialFill = 0x0l;
long[] checksums = CRCUtil.generate(messageSize, crcSize, poly, initialFill, true);
StringBuilder sb = new StringBuilder();
sb.append("private static int[] CHECKSUMS = new int[]{");
@@ -238,7 +233,29 @@ public class CRCUtil
}
sb.append("};");
System.out.println("Checksums:\n" + sb);
String hex = "7CFC0039420170452A4F9970000000000000000000D05";
CorrectedBinaryMessage message = new CorrectedBinaryMessage(BinaryMessage.loadHex(hex));
int calculated = 0xFFF; //Initial fill of all ones
int messageStart = 0;
/* Iterate the set bits and XOR running checksum with lookup value */
for(int i = message.nextSetBit(messageStart);
i >= messageStart && i < messageSize;
i = message.nextSetBit(i + 1))
{
System.out.println("Bit [" + i + "] is set");
calculated ^= checksums[i];
}
int checksum = message.getInt(messageSize, messageSize + crcSize - 1);
int residual = calculated ^ checksum;
mLog.debug("CALC:" + Integer.toHexString(calculated).toUpperCase() +
" CHECK:" + Integer.toHexString(checksum).toUpperCase() +
" RESIDUAL:" + Integer.toHexString(residual).toUpperCase());
}
}