From 2b9187ac736feeb661e2814af8fa534a335998d4 Mon Sep 17 00:00:00 2001 From: Anton Tananaev Date: Tue, 6 Oct 2015 16:55:31 +1300 Subject: Clean up CRC-16 implementations --- src/org/traccar/helper/Checksum.java | 38 +++++++++++++++------- .../traccar/protocol/CastelProtocolDecoder.java | 4 +-- .../traccar/protocol/CityeasyProtocolEncoder.java | 2 +- src/org/traccar/protocol/Gt06ProtocolDecoder.java | 2 +- src/org/traccar/protocol/Gt06ProtocolEncoder.java | 2 +- .../traccar/protocol/MeiligaoProtocolDecoder.java | 2 +- .../traccar/protocol/NavigilProtocolDecoder.java | 2 +- 7 files changed, 33 insertions(+), 19 deletions(-) (limited to 'src/org/traccar') diff --git a/src/org/traccar/helper/Checksum.java b/src/org/traccar/helper/Checksum.java index cdf1bbf50..69c9dd499 100644 --- a/src/org/traccar/helper/Checksum.java +++ b/src/org/traccar/helper/Checksum.java @@ -91,8 +91,14 @@ public class Checksum { 0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0 }; - public static final int CRC16_CCITT = 0xFFFF; - public static final int CRC16_CCITT_XOROUT = 0xFFFF; + // More info: http://reveng.sourceforge.net/crc-catalogue/16.htm + public static final String CRC16_X25 = "X-25"; + public static final String CRC16_CCITT_FALSE = "CCITT-FALSE"; + public static final String CRC16_KERMIT = "KERMIT"; + public static final String CRC16_XMODEM = "XMODEM"; + public static final String CRC16_AUG_CCITT = "AUG-CCITT"; + public static final String CRC16_GENIBUS = "GENIBUS"; + public static final String CRC16_MCRF4XX = "MCRF4XX"; private static int crc16Unreflected(ByteBuffer buf, int crc_in, int[] table) { int crc16 = crc_in; @@ -110,16 +116,24 @@ public class Checksum { return crc16 & 0xFFFF; } - public static int crc16Ccitt(ByteBuffer buf) { - return crc16Reflected(buf, 0xFFFF, CRC16_CCITT_TABLE_REVERSE) ^ 0xFFFF; - } - - public static int crc16X25Ccitt(ByteBuffer buf) { - return crc16Unreflected(buf, 0xFFFF, CRC16_CCITT_TABLE); - } - - public static int crc16Ccitt(ByteBuffer buf, int seed, int xorout) { - return crc16Reflected(buf, seed, CRC16_CCITT_TABLE_REVERSE) ^ xorout; + public static int crc16(String type, ByteBuffer buf) { + switch (type) { + case CRC16_X25: + return crc16Reflected(buf, 0xFFFF, CRC16_CCITT_TABLE_REVERSE) ^ 0xFFFF; + case CRC16_CCITT_FALSE: + return crc16Unreflected(buf, 0xFFFF, CRC16_CCITT_TABLE); + case CRC16_KERMIT: + return crc16Reflected(buf, 0, CRC16_CCITT_TABLE_REVERSE); + case CRC16_XMODEM: + return crc16Unreflected(buf, 0, CRC16_CCITT_TABLE); + case CRC16_AUG_CCITT: + return crc16Unreflected(buf, 0x1d0f, CRC16_CCITT_TABLE); + case CRC16_GENIBUS: + return crc16Unreflected(buf, 0xFFFF, CRC16_CCITT_TABLE) ^ 0xFFFF; + case CRC16_MCRF4XX: + return crc16Reflected(buf, 0xFFFF, CRC16_CCITT_TABLE_REVERSE); + } + throw new UnsupportedOperationException(); } public static int crc32(ByteBuffer buf) { diff --git a/src/org/traccar/protocol/CastelProtocolDecoder.java b/src/org/traccar/protocol/CastelProtocolDecoder.java index f93b9762c..d7c6bbf46 100644 --- a/src/org/traccar/protocol/CastelProtocolDecoder.java +++ b/src/org/traccar/protocol/CastelProtocolDecoder.java @@ -95,7 +95,7 @@ public class CastelProtocolDecoder extends BaseProtocolDecoder { response.writeByte(version); response.writeBytes(id); response.writeShort(ChannelBuffers.swapShort(MSG_HEARTBEAT_RESPONSE)); - response.writeShort(Checksum.crc16Ccitt(response.toByteBuffer(0, response.writerIndex()))); + response.writeShort(Checksum.crc16(Checksum.CRC16_X25, response.toByteBuffer(0, response.writerIndex()))); response.writeByte(0x0D); response.writeByte(0x0A); channel.write(response, remoteAddress); } @@ -123,7 +123,7 @@ public class CastelProtocolDecoder extends BaseProtocolDecoder { response.writeInt(0xFFFFFFFF); response.writeShort(0); response.writeInt((int) (System.currentTimeMillis() / 1000)); - response.writeShort(Checksum.crc16Ccitt(response.toByteBuffer(0, response.writerIndex()))); + response.writeShort(Checksum.crc16(Checksum.CRC16_X25, response.toByteBuffer(0, response.writerIndex()))); response.writeByte(0x0D); response.writeByte(0x0A); channel.write(response, remoteAddress); } diff --git a/src/org/traccar/protocol/CityeasyProtocolEncoder.java b/src/org/traccar/protocol/CityeasyProtocolEncoder.java index cfe69a462..76c4199e1 100644 --- a/src/org/traccar/protocol/CityeasyProtocolEncoder.java +++ b/src/org/traccar/protocol/CityeasyProtocolEncoder.java @@ -33,7 +33,7 @@ public class CityeasyProtocolEncoder extends BaseProtocolEncoder { buf.writeShort(type); buf.writeBytes(content); buf.writeInt(0x0B); - buf.writeShort(Checksum.crc16Ccitt(buf.toByteBuffer(), 0, 0)); + buf.writeShort(Checksum.crc16(Checksum.CRC16_KERMIT, buf.toByteBuffer())); buf.writeByte('\r'); buf.writeByte('\n'); diff --git a/src/org/traccar/protocol/Gt06ProtocolDecoder.java b/src/org/traccar/protocol/Gt06ProtocolDecoder.java index ab5c80cf6..4c744dd9f 100644 --- a/src/org/traccar/protocol/Gt06ProtocolDecoder.java +++ b/src/org/traccar/protocol/Gt06ProtocolDecoder.java @@ -81,7 +81,7 @@ public class Gt06ProtocolDecoder extends BaseProtocolDecoder { response.writeByte(0x05); // size response.writeByte(type); response.writeShort(index); - response.writeShort(Checksum.crc16Ccitt(response.toByteBuffer(2, 4))); + response.writeShort(Checksum.crc16(Checksum.CRC16_X25, response.toByteBuffer(2, 4))); response.writeByte(0x0D); response.writeByte(0x0A); // ending channel.write(response); } diff --git a/src/org/traccar/protocol/Gt06ProtocolEncoder.java b/src/org/traccar/protocol/Gt06ProtocolEncoder.java index 9a1bb4571..f5b914b1c 100644 --- a/src/org/traccar/protocol/Gt06ProtocolEncoder.java +++ b/src/org/traccar/protocol/Gt06ProtocolEncoder.java @@ -40,7 +40,7 @@ public class Gt06ProtocolEncoder extends BaseProtocolEncoder { buf.writeShort(0); // message index - buf.writeShort(Checksum.crc16Ccitt(buf.toByteBuffer(2, buf.writerIndex() - 2))); + buf.writeShort(Checksum.crc16(Checksum.CRC16_X25, buf.toByteBuffer(2, buf.writerIndex() - 2))); buf.writeByte('\r'); buf.writeByte('\n'); diff --git a/src/org/traccar/protocol/MeiligaoProtocolDecoder.java b/src/org/traccar/protocol/MeiligaoProtocolDecoder.java index bde28492f..a7d8a884e 100644 --- a/src/org/traccar/protocol/MeiligaoProtocolDecoder.java +++ b/src/org/traccar/protocol/MeiligaoProtocolDecoder.java @@ -121,7 +121,7 @@ public class MeiligaoProtocolDecoder extends BaseProtocolDecoder { buf.writeBytes(id); buf.writeShort(type); buf.writeBytes(msg); - buf.writeShort(Checksum.crc16X25Ccitt(buf.toByteBuffer())); + buf.writeShort(Checksum.crc16(Checksum.CRC16_CCITT_FALSE, buf.toByteBuffer())); buf.writeByte('\r'); buf.writeByte('\n'); diff --git a/src/org/traccar/protocol/NavigilProtocolDecoder.java b/src/org/traccar/protocol/NavigilProtocolDecoder.java index 24c6618bb..142d19fc6 100644 --- a/src/org/traccar/protocol/NavigilProtocolDecoder.java +++ b/src/org/traccar/protocol/NavigilProtocolDecoder.java @@ -68,7 +68,7 @@ public class NavigilProtocolDecoder extends BaseProtocolDecoder { header.writeShort(MESSAGE_ACKNOWLEDGEMENT); header.writeShort(header.capacity() + data.capacity()); header.writeShort(0); - header.writeShort(Checksum.crc16X25Ccitt(data.toByteBuffer())); + header.writeShort(Checksum.crc16(Checksum.CRC16_CCITT_FALSE, data.toByteBuffer())); header.writeInt(0); header.writeInt((int) (System.currentTimeMillis() / 1000) + LEAP_SECONDS_DELTA); -- cgit v1.2.3