From 546f565023575c0975b7cc8fa3b9dea2f420918b Mon Sep 17 00:00:00 2001 From: anton2920 Date: Mon, 5 Sep 2022 11:21:45 +0100 Subject: Added support for escaping byte sequences --- .../org/traccar/protocol/G1rusProtocolDecoder.java | 107 +++++++++++++++------ 1 file changed, 75 insertions(+), 32 deletions(-) (limited to 'src/main/java/org') diff --git a/src/main/java/org/traccar/protocol/G1rusProtocolDecoder.java b/src/main/java/org/traccar/protocol/G1rusProtocolDecoder.java index 89303d1b1..d962e601e 100644 --- a/src/main/java/org/traccar/protocol/G1rusProtocolDecoder.java +++ b/src/main/java/org/traccar/protocol/G1rusProtocolDecoder.java @@ -3,6 +3,7 @@ package org.traccar.protocol; import com.google.common.primitives.Doubles; import com.google.common.primitives.Ints; import com.google.common.primitives.Longs; +import com.google.common.primitives.Shorts; import io.netty.buffer.ByteBuf; import io.netty.channel.Channel; import org.slf4j.Logger; @@ -63,6 +64,50 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { private static final int G1RUS_GPS_VDOP_MASK = 0b01000000; private static final int G1RUS_GPS_STAT_MASK = 0b10000000; + private static final int G1RUS_ESCAPE_CHAR = 0x1B; + + + private byte readUnsignedByteUnescaped(ByteBuf buf) { + byte first = (byte) buf.readUnsignedByte(); + if (first != G1RUS_ESCAPE_CHAR) { + return first; + } else { /* first == 0x1B */ + byte second = (byte) buf.readUnsignedByte(); + if (second == 0x00) { + return first; + } else { /* second == 0xE3 */ + return (byte) 0xF8; + } + } + } + + + private void readBytesUnescaped(ByteBuf buf, byte[] to) { + for (int i = 0; i < to.length; ++i) { + to[i] = readUnsignedByteUnescaped(buf); + } + } + + private void readBytesUnescaped(ByteBuf buf, byte[] to, int dstIndex, int length) { + for (int i = dstIndex; i < length; ++i) { + to[i] = readUnsignedByteUnescaped(buf); + } + } + + + private short readUnsignedShortUnescaped(ByteBuf buf) { + byte[] shortBuf = new byte[2]; + readBytesUnescaped(buf, shortBuf); + return Shorts.fromByteArray(shortBuf); + } + + + private int readIntUnescaped(ByteBuf buf) { + byte[] intBuf = new byte[4]; + readBytesUnescaped(buf, intBuf); + return Ints.fromByteArray(intBuf); + } + private void decodeSYSSub(ByteBuf buf) { LOGGER.info(""); @@ -75,23 +120,23 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { */ /* Device name */ - byte devNameLen = (byte) buf.readUnsignedByte(); + byte devNameLen = readUnsignedByteUnescaped(buf); byte[] devName = new byte[devNameLen & 0xF]; - buf.readBytes(devName); + readBytesUnescaped(buf, devName); String devNameString = new String(devName); LOGGER.info("Device name: " + devNameString); /* Firmware version */ - byte firmwareLen = (byte) buf.readUnsignedByte(); + byte firmwareLen = readUnsignedByteUnescaped(buf); byte[] firmware = new byte[firmwareLen & 0xF]; - buf.readBytes(firmware); + readBytesUnescaped(buf, firmware); String firmwareString = new String(firmware); LOGGER.info("Firmware version: " + firmwareString); /* Hardware version */ - byte hardwareLen = (byte) buf.readUnsignedByte(); + byte hardwareLen = readUnsignedByteUnescaped(buf); byte[] hardware = new byte[hardwareLen & 0xF]; - buf.readBytes(hardware); + readBytesUnescaped(buf, hardware); String hardwareString = new String(hardware); LOGGER.info("Hardware version: " + hardwareString); @@ -104,30 +149,30 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { buf.skipBytes(1); /* Total length */ - short subMask = (short) buf.readUnsignedShort(); + short subMask = readUnsignedShortUnescaped(buf); if ((subMask & G1RUS_GPS_SIGN_MASK) == G1RUS_GPS_SIGN_MASK) { buf.skipBytes(1); } if ((subMask & G1RUS_GPS_POS_MASK) == G1RUS_GPS_POS_MASK) { byte[] pos_buf = new byte[4]; - buf.readBytes(pos_buf); + readBytesUnescaped(buf, pos_buf); position.setLatitude((float) Ints.fromByteArray(pos_buf) / 1000000); LOGGER.info("Latitude: " + position.getLatitude()); - buf.readBytes(pos_buf); + readBytesUnescaped(buf, pos_buf); position.setLongitude((float) Ints.fromByteArray(pos_buf) / 1000000); LOGGER.info("Longitude: " + position.getLongitude()); } if ((subMask & G1RUS_GPS_SPD_MASK) == G1RUS_GPS_SPD_MASK) { - position.setSpeed(buf.readUnsignedShort()); + position.setSpeed(readUnsignedShortUnescaped(buf)); LOGGER.info("Speed: " + position.getSpeed()); } if ((subMask & G1RUS_GPS_AZTH_MASK) == G1RUS_GPS_AZTH_MASK) { - position.setCourse(buf.readUnsignedShort()); + position.setCourse(readUnsignedShortUnescaped(buf)); LOGGER.info("Course: " + position.getCourse()); } if ((subMask & G1RUS_GPS_ALT_MASK) == G1RUS_GPS_ALT_MASK) { - position.setAltitude(buf.readUnsignedShort()); + position.setAltitude(readUnsignedShortUnescaped(buf)); LOGGER.info("Altitude: " + position.getAltitude()); } if ((subMask & G1RUS_GPS_HDOP_MASK) == G1RUS_GPS_HDOP_MASK) { @@ -147,7 +192,7 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { private Position decodeRegular(Channel channel, SocketAddress remoteAddress, ByteBuf buf, long imei, byte packetType) { - int timestamp_ = buf.readInt(); + int timestamp_ = readIntUnescaped(buf); long timestamp = (946684800 + timestamp_) * 1000L; /* Convert received time to proper UNIX timestamp */ LOGGER.info("Date and time: " + new SimpleDateFormat("yyyy.MM.dd HH:mm:ss").format(new Date(timestamp))); @@ -158,7 +203,7 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { DeviceSession deviceSession = null; Position position = null; - short dataUploadingMask = (short) buf.readUnsignedShort(); + short dataUploadingMask = readUnsignedShortUnescaped(buf); if ((dataUploadingMask & G1RUS_DATA_SYS_MASK) == G1RUS_DATA_SYS_MASK) { decodeSYSSub(buf); } @@ -174,24 +219,24 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { decodeGPSSub(buf, position); } if ((dataUploadingMask & G1RUS_DATA_GSM_MASK) == G1RUS_DATA_GSM_MASK) { - buf.skipBytes(buf.readUnsignedByte()); + buf.skipBytes(readUnsignedByteUnescaped(buf)); } if ((dataUploadingMask & G1RUS_DATA_COT_MASK) == G1RUS_DATA_COT_MASK) { - buf.skipBytes(buf.readUnsignedByte()); + buf.skipBytes(readUnsignedByteUnescaped(buf)); } if ((dataUploadingMask & G1RUS_DATA_ADC_MASK) == G1RUS_DATA_ADC_MASK) { /*if (deviceSession == null) { return null; }*/ - buf.skipBytes(buf.readUnsignedByte()); + buf.skipBytes(readUnsignedByteUnescaped(buf)); // decodeADCSub(buf, position); } if ((dataUploadingMask & G1RUS_DATA_DTT_MASK) == G1RUS_DATA_DTT_MASK) { - buf.skipBytes(buf.readUnsignedByte()); + buf.skipBytes(readUnsignedByteUnescaped(buf)); } if ((dataUploadingMask & G1RUS_DATA_ETD_MASK) == G1RUS_DATA_ETD_MASK) { - buf.skipBytes(buf.readUnsignedByte()); + buf.skipBytes(readUnsignedByteUnescaped(buf)); } return position; @@ -220,15 +265,17 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { protected Object decode(Channel channel, SocketAddress remoteAddress, Object msg) throws Exception { ByteBuf buf = (ByteBuf) msg; - buf.skipBytes(1); /* Head */ + if (buf.readUnsignedByte() != G1RUS_HEAD_TAIL) { + return null; + } - LOGGER.info("Protocol version: " + buf.readUnsignedByte()); + LOGGER.info("Protocol version: " + readUnsignedByteUnescaped(buf)); - byte packetType = (byte) buf.readUnsignedByte(); + byte packetType = readUnsignedByteUnescaped(buf); printPacketType(packetType); byte[] imei = new byte[8]; - buf.readBytes(imei, 0, 7); + readBytesUnescaped(buf, imei, 0, 7); long imei_long = Longs.fromByteArray(imei); LOGGER.info("IMEI: " + imei_long); @@ -249,22 +296,18 @@ public class G1rusProtocolDecoder extends BaseProtocolDecoder { } else if ((packetType & G1RUS_TYPE_BCD_MASK) == G1RUS_TYPE_MIXED) { positions = new LinkedList<>(); - while (buf.readableBytes() > 3) { - short subPacketLength = (short) buf.readUnsignedShort(); - byte subPacketType = (byte) buf.readUnsignedByte(); + while (buf.readableBytes() > 5) { + short subPacketLength = readUnsignedShortUnescaped(buf); + byte subPacketType = readUnsignedByteUnescaped(buf); printPacketType(subPacketType); if ((subPacketType & G1RUS_TYPE_BCD_MASK) == G1RUS_TYPE_REGULAR) { - Position position = decodeRegular(channel, remoteAddress, buf, imei_long, packetType); + Position position = decodeRegular(channel, remoteAddress, buf, imei_long, subPacketType); if (position != null) { positions.add(position); } } else { - try { - buf.skipBytes(subPacketLength - 1); - } catch (Exception e) { - return positions; - } + buf.skipBytes(subPacketLength - 1); } /* else if ((subPacketType & G1RUS_TYPE_BCD_MASK) == G1RUS_TYPE_SMS_FORWARD) { buf.skipBytes(subPacketLength - 1); -- cgit v1.2.3