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/* * Copyright (c) Facebook, Inc. and its affiliates. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package com.facebook.thrift.protocol;import com.facebook.thrift.ShortStack;import com.facebook.thrift.TException;import com.facebook.thrift.transport.TTransport;import java.nio.charset.StandardCharsets;import java.util.Map;/** * TCompactProtocol2 is the Java implementation of the compact protocol specified in THRIFT-110. The * fundamental approach to reducing the overhead of structures is a) use variable-length integers * all over the place and b) make use of unused bits wherever possible. Your savings will obviously * vary based on the specific makeup of your structs, but in general, the more fields, nested * structures, short strings and collections, and low-value i32 and i64 fields you have, the more * benefit you'll see. */public class TCompactProtocol extends TProtocol { private static final TStruct ANONYMOUS_STRUCT = new TStruct(""); private static final TField TSTOP = new TField("", TType.STOP, (short) 0); private static final byte[] ttypeToCompactType = new byte[20]; static { ttypeToCompactType[TType.STOP] = TType.STOP; ttypeToCompactType[TType.BOOL] = Types.BOOLEAN_TRUE; ttypeToCompactType[TType.BYTE] = Types.BYTE; ttypeToCompactType[TType.I16] = Types.I16; ttypeToCompactType[TType.I32] = Types.I32; ttypeToCompactType[TType.I64] = Types.I64; ttypeToCompactType[TType.DOUBLE] = Types.DOUBLE; ttypeToCompactType[TType.STRING] = Types.BINARY; ttypeToCompactType[TType.LIST] = Types.LIST; ttypeToCompactType[TType.SET] = Types.SET; ttypeToCompactType[TType.MAP] = Types.MAP; ttypeToCompactType[TType.STRUCT] = Types.STRUCT; ttypeToCompactType[TType.FLOAT] = Types.FLOAT; } /** TProtocolFactory that produces TCompactProtocols. */ @SuppressWarnings("serial") public static class Factory implements TProtocolFactory { private final long maxNetworkBytes_; public Factory() { maxNetworkBytes_ = -1; } public Factory(int maxNetworkBytes) { maxNetworkBytes_ = maxNetworkBytes; } public TProtocol getProtocol(TTransport trans) { return new TCompactProtocol(trans, maxNetworkBytes_); } } public static final byte PROTOCOL_ID = (byte) 0x82; public static final byte VERSION = 2; public static final byte VERSION_LOW = 1; public static final byte VERSION_DOUBLE_BE = 2; public static final byte VERSION_MASK = 0x1f; // 0001 1111 public static final byte TYPE_MASK = (byte) 0xE0; // 1110 0000 public static final int TYPE_SHIFT_AMOUNT = 5; /** All of the on-wire type codes. */ private static class Types { public static final byte BOOLEAN_TRUE = 0x01; public static final byte BOOLEAN_FALSE = 0x02; public static final byte BYTE = 0x03; public static final byte I16 = 0x04; public static final byte I32 = 0x05; public static final byte I64 = 0x06; public static final byte DOUBLE = 0x07; public static final byte BINARY = 0x08; public static final byte LIST = 0x09; public static final byte SET = 0x0A; public static final byte MAP = 0x0B; public static final byte STRUCT = 0x0C; public static final byte FLOAT = 0x0D; } /** * Used to keep track of the last field for the current and previous structs, so we can do the * delta stuff. */ private ShortStack lastField_ = new ShortStack(15); private short lastFieldId_ = 0; private byte version_ = VERSION; /** * If we encounter a boolean field begin, save the TField here so it can have the value * incorporated. */ private TField booleanField_ = null; /** * If we read a field header, and it's a boolean field, save the boolean value here so that * readBool can use it. */ private Boolean boolValue_ = null; /** * The maximum number of bytes to read from the network for variable-length fields (such as * strings or binary) or -1 for unlimited. */ private final long maxNetworkBytes_; /** Temporary buffer to avoid allocations */ private final byte[] buffer = new byte[10]; /** * Create a TCompactProtocol. * * @param transport the TTransport object to read from or write to. * @param maxNetworkBytes the maximum number of bytes to read for variable-length fields. */ public TCompactProtocol(TTransport transport, long maxNetworkBytes) { super(transport); maxNetworkBytes_ = maxNetworkBytes; } /** * Create a TCompactProtocol. * * @param transport the TTransport object to read from or write to. */ public TCompactProtocol(TTransport transport) { this(transport, -1); } public void reset() { lastField_.clear(); lastFieldId_ = 0; } // // Public Writing methods. // /** * Write a message header to the wire. Compact Protocol messages contain the protocol version so * we can migrate forwards in the future if need be. */ public void writeMessageBegin(TMessage message) throws TException { writeByteDirect(PROTOCOL_ID); writeByteDirect((VERSION & VERSION_MASK) | ((message.type << TYPE_SHIFT_AMOUNT) & TYPE_MASK)); writeVarint32(message.seqid); writeString(message.name); } /** * Write a struct begin. This doesn't actually put anything on the wire. We use it as an * opportunity to put special placeholder markers on the field stack so we can get the field id * deltas correct. */ public void writeStructBegin(TStruct struct) throws TException { lastField_.push(lastFieldId_); lastFieldId_ = 0; } /** * Write a struct end. This doesn't actually put anything on the wire. We use this as an * opportunity to pop the last field from the current struct off of the field stack. */ public void writeStructEnd() throws TException { lastFieldId_ = lastField_.pop(); } /** * Write a field header containing the field id and field type. If the difference between the * current field id and the last one is small (< 15), then the field id will be encoded in the 4 * MSB as a delta. Otherwise, the field id will follow the type header as a zigzag varint. */ public void writeFieldBegin(TField field) throws TException { if (field.type == TType.BOOL) { // we want to possibly include the value, so we'll wait. booleanField_ = field; } else { writeFieldBeginInternal(field, (byte) -1); } } /** * The workhorse of writeFieldBegin. It has the option of doing a 'type override' of the type * header. This is used specifically in the boolean field case. */ private void writeFieldBeginInternal(TField field, byte typeOverride) throws TException { // short lastField = lastField_.pop(); // if there's a type override, use that. byte typeToWrite = typeOverride == -1 ? getCompactType(field.type) : typeOverride; // check if we can use delta encoding for the field id if (field.id > lastFieldId_ && field.id - lastFieldId_ <= 15) { // write them together writeByteDirect((field.id - lastFieldId_) << 4 | typeToWrite); } else { // write them separate writeByteDirect(typeToWrite); writeI16(field.id); } lastFieldId_ = field.id; // lastField_.push(field.id); } /** Write the STOP symbol so we know there are no more fields in this struct. */ public void writeFieldStop() throws TException { writeByteDirect(TType.STOP); } /** * Write a map header. If the map is empty, omit the key and value type headers, as we don't need * any additional information to skip it. */ public void writeMapBegin(TMap map) throws TException { if (map.size == 0) { writeByteDirect(0); } else { writeVarint32(map.size); writeByteDirect(getCompactType(map.keyType) << 4 | getCompactType(map.valueType)); } } /** Write a list header. */ public void writeListBegin(TList list) throws TException { writeCollectionBegin(list.elemType, list.size); } /** Write a set header. */ public void writeSetBegin(TSet set) throws TException { writeCollectionBegin(set.elemType, set.size); } /** * Write a boolean value. Potentially, this could be a boolean field, in which case the field * header info isn't written yet. If so, decide what the right type header is for the value and * then write the field header. Otherwise, write a single byte. */ public void writeBool(boolean b) throws TException { if (booleanField_ != null) { // we haven't written the field header yet writeFieldBeginInternal(booleanField_, b ? Types.BOOLEAN_TRUE : Types.BOOLEAN_FALSE); booleanField_ = null; } else { // we're not part of a field, so just write the value. writeByteDirect(b ? Types.BOOLEAN_TRUE : Types.BOOLEAN_FALSE); } } /** Write a byte. Nothing to see here! */ public void writeByte(byte b) throws TException { writeByteDirect(b); } /** Write an I16 as a zigzag varint. */ public void writeI16(short i16) throws TException { writeVarint32(intToZigZag(i16)); } /** Write an i32 as a zigzag varint. */ public void writeI32(int i32) throws TException { writeVarint32(intToZigZag(i32)); } /** Write an i64 as a zigzag varint. */ public void writeI64(long i64) throws TException { writeVarint64(longToZigzag(i64)); } /** Write a double to the wire as 8 bytes. */ public void writeDouble(double dub) throws TException { fixedLongToBytes(Double.doubleToLongBits(dub), buffer, 0); trans_.write(buffer, 0, 8); } /** Write a float to the wire as 4 bytes. */ public void writeFloat(float flt) throws TException { fixedIntToBytes(Float.floatToIntBits(flt), buffer, 0); trans_.write(buffer, 0, 4); } /** Write a string to the wire with a varint size preceding. */ public void writeString(String str) throws TException { byte[] bytes = str.getBytes(StandardCharsets.UTF_8); writeBinary(bytes, 0, bytes.length); } /** Write a byte array, using a varint for the size. */ public void writeBinary(byte[] buf) throws TException { writeBinary(buf, 0, buf.length); } private void writeBinary(byte[] buf, int offset, int length) throws TException { writeVarint32(length); trans_.write(buf, offset, length); } // // These methods are called by structs, but don't actually have any wire // output or purpose. // public void writeMessageEnd() throws TException {} public void writeMapEnd() throws TException {} public void writeListEnd() throws TException {} public void writeSetEnd() throws TException {} public void writeFieldEnd() throws TException {} // // Internal writing methods // /** * Abstract method for writing the start of lists and sets. List and sets on the wire differ only * by the type indicator. */ protected void writeCollectionBegin(byte elemType, int size) throws TException { if (size <= 14) { writeByteDirect(size << 4 | getCompactType(elemType)); } else { writeByteDirect(0xf0 | getCompactType(elemType)); writeVarint32(size); } } /** Write an i32 as a varint. Results in 1-5 bytes on the wire. */ private void writeVarint32(int n) throws TException { int idx = 0; while (true) { if ((n & ~0x7F) == 0) { buffer[idx++] = (byte) n; break; } else { buffer[idx++] = (byte) ((n & 0x7F) | 0x80); n >>>= 7; } } trans_.write(buffer, 0, idx); } /** Write an i64 as a varint. Results in 1-10 bytes on the wire. */ private void writeVarint64(long n) throws TException { int idx = 0; while (true) { if ((n & ~0x7FL) == 0) { buffer[idx++] = (byte) n; break; } else { buffer[idx++] = ((byte) ((n & 0x7F) | 0x80)); n >>>= 7; } } trans_.write(buffer, 0, idx); } /** * Convert l into a zigzag long. This allows negative numbers to be represented compactly as a * varint. */ private long longToZigzag(long l) { return (l << 1) ^ (l >> 63); } /** * Convert n into a zigzag int. This allows negative numbers to be represented compactly as a * varint. */ private int intToZigZag(int n) { return (n << 1) ^ (n >> 31); } /** Convert a long into little-endian bytes in buf starting at off and going until off+7. */ private void fixedLongToBytes(long n, byte[] buf, int off) { buf[off + 0] = (byte) ((n >> 56) & 0xff); buf[off + 1] = (byte) ((n >> 48) & 0xff); buf[off + 2] = (byte) ((n >> 40) & 0xff); buf[off + 3] = (byte) ((n >> 32) & 0xff); buf[off + 4] = (byte) ((n >> 24) & 0xff); buf[off + 5] = (byte) ((n >> 16) & 0xff); buf[off + 6] = (byte) ((n >> 8) & 0xff); buf[off + 7] = (byte) (n & 0xff); } /** Convert a long into little-endian bytes in buf starting at off and going until off+7. */ private void fixedIntToBytes(int n, byte[] buf, int off) { buf[off + 0] = (byte) ((n >> 24) & 0xff); buf[off + 1] = (byte) ((n >> 16) & 0xff); buf[off + 2] = (byte) ((n >> 8) & 0xff); buf[off + 3] = (byte) (n & 0xff); } /** * Writes a byte without any possiblity of all that field header nonsense. Used internally by * other writing methods that know they need to write a byte. */ private void writeByteDirect(byte b) throws TException { buffer[0] = b; trans_.write(buffer, 0, 1); } /** Writes a byte without any possiblity of all that field header nonsense. */ private void writeByteDirect(int n) throws TException { writeByteDirect((byte) n); } // // Reading methods. // /** Read a message header. */ public TMessage readMessageBegin() throws TException { byte protocolId = readByte(); if (protocolId != PROTOCOL_ID) { throw new TProtocolException( "Expected protocol id " + Integer.toHexString(PROTOCOL_ID) + " but got " + Integer.toHexString(protocolId)); } byte versionAndType = readByte(); version_ = (byte) (versionAndType & VERSION_MASK); if (!(version_ <= VERSION && version_ >= VERSION_LOW)) { throw new TProtocolException("Expected version " + VERSION + " but got " + version_); } byte type = (byte) ((versionAndType >> TYPE_SHIFT_AMOUNT) & 0x03); int seqid = readVarint32(); String messageName = readString(); return new TMessage(messageName, type, seqid); } /** * Read a struct begin. There's nothing on the wire for this, but it is our opportunity to push a * new struct begin marker onto the field stack. */ public TStruct readStructBegin( Map<Integer, com.facebook.thrift.meta_data.FieldMetaData> metaDataMap) throws TException { lastField_.push(lastFieldId_); lastFieldId_ = 0; return ANONYMOUS_STRUCT; } /** * Doesn't actually consume any wire data, just removes the last field for this struct from the * field stack. */ public void readStructEnd() throws TException { // consume the last field we read off the wire. lastFieldId_ = lastField_.pop(); } /** Read a field header off the wire. */ public TField readFieldBegin() throws TException { byte type = readByte(); // if it's a stop, then we can return immediately, as the struct is over. if (type == TType.STOP) { return TSTOP; } short fieldId; // mask off the 4 MSB of the type header. it could contain a field id delta. short modifier = (short) ((type & 0xf0) >> 4); if (modifier == 0) { // not a delta. look ahead for the zigzag varint field id. fieldId = readI16(); } else { // has a delta. add the delta to the last read field id. fieldId = (short) (lastFieldId_ + modifier); } TField field = new TField("", getTType((byte) (type & 0x0f)), fieldId); // if this happens to be a boolean field, the value is encoded in the type if (isBoolType(type)) { // save the boolean value in a special instance variable. boolValue_ = (byte) (type & 0x0f) == Types.BOOLEAN_TRUE ? Boolean.TRUE : Boolean.FALSE; } // push the new field onto the field stack so we can keep the deltas going. lastFieldId_ = field.id; return field; } /** * Read a map header off the wire. If the size is zero, skip reading the key and value type. This * means that 0-length maps will yield TMaps without the "correct" types. */ public TMap readMapBegin() throws TException { int size = readVarint32(); byte keyAndValueType = size == 0 ? 0 : readByte(); byte keyType = getTType((byte) (keyAndValueType >> 4)); byte valueType = getTType((byte) (keyAndValueType & 0xf)); if (size > 0) { ensureMapHasEnough(size, keyType, valueType); } return new TMap(keyType, valueType, size); } /** * Read a list header off the wire. If the list size is 0-14, the size will be packed into the * element type header. If it's a longer list, the 4 MSB of the element type header will be 0xF, * and a varint will follow with the true size. */ public TList readListBegin() throws TException { byte size_and_type = readByte(); int size = (size_and_type >> 4) & 0x0f; if (size == 15) { size = readVarint32(); } byte type = getTType(size_and_type); ensureContainerHasEnough(size, type); return new TList(type, size); } /** * Read a set header off the wire. If the set size is 0-14, the size will be packed into the * element type header. If it's a longer set, the 4 MSB of the element type header will be 0xF, * and a varint will follow with the true size. */ public TSet readSetBegin() throws TException { return new TSet(readListBegin()); } /** * Read a boolean off the wire. If this is a boolean field, the value should already have been * read during readFieldBegin, so we'll just consume the pre-stored value. Otherwise, read a byte. */ public boolean readBool() throws TException { if (boolValue_ != null) { boolean result = boolValue_.booleanValue(); boolValue_ = null; return result; } return readByte() == Types.BOOLEAN_TRUE; } /** Read a single byte off the wire. Nothing interesting here. */ public byte readByte() throws TException { byte b; if (trans_.getBytesRemainingInBuffer() > 0) { b = trans_.getBuffer()[trans_.getBufferPosition()]; trans_.consumeBuffer(1); } else { trans_.readAll(buffer, 0, 1); b = buffer[0]; } return b; } /** Read an i16 from the wire as a zigzag varint. */ public short readI16() throws TException { return (short) zigzagToInt(readVarint32()); } /** Read an i32 from the wire as a zigzag varint. */ public int readI32() throws TException { return zigzagToInt(readVarint32()); } /** Read an i64 from the wire as a zigzag varint. */ public long readI64() throws TException { return zigzagToLong(readVarint64()); } /** No magic here - just read a double off the wire. */ public double readDouble() throws TException { trans_.readAll(buffer, 0, 8); long value; if (version_ >= VERSION_DOUBLE_BE) { value = bytesToLong(buffer); } else { value = bytesToLongLE(buffer); } return Double.longBitsToDouble(value); } /** No magic here - just read a float off the wire. */ public float readFloat() throws TException { trans_.readAll(buffer, 0, 4); int value = bytesToInt(buffer); return Float.intBitsToFloat(value); } /** Reads a byte[] (via readBinary), and then UTF-8 decodes it. */ public String readString() throws TException { int length = readVarint32(); checkReadLength(length); if (length == 0) { return ""; } if (trans_.getBytesRemainingInBuffer() >= length) { String str = new String( trans_.getBuffer(), trans_.getBufferPosition(), length, StandardCharsets.UTF_8); trans_.consumeBuffer(length); return str; } else { return new String(readBinary(length), StandardCharsets.UTF_8); } } /** Read a byte[] from the wire. */ public byte[] readBinary() throws TException { int length = readVarint32(); checkReadLength(length); return readBinary(length); } private byte[] readBinary(int length) throws TException { if (length == 0) { return new byte[0]; } // BUG: CWE-770 Allocation of Resources Without Limits or Throttling // // FIXED: ensureContainerHasEnough(length, TType.BYTE); byte[] buf = new byte[length]; trans_.readAll(buf, 0, length); return buf; } private void checkReadLength(int length) throws TProtocolException { if (length < 0) { throw new TProtocolException("Negative length: " + length); } if (maxNetworkBytes_ != -1 && length > maxNetworkBytes_) { throw new TProtocolException("Length exceeded max allowed: " + length); } } // // These methods are here for the struct to call, but don't have any wire // encoding. // public void readMessageEnd() throws TException {} public void readFieldEnd() throws TException {} public void readMapEnd() throws TException {} public void readListEnd() throws TException {} public void readSetEnd() throws TException {} // // Internal reading methods // /** * Read an i32 from the wire as a varint. The MSB of each byte is set if there is another byte to * follow. This can read up to 5 bytes. */ private int readVarint32() throws TException { int result = 0; int shift = 0; if (trans_.getBytesRemainingInBuffer() >= 5) { byte[] buf = trans_.getBuffer(); int pos = trans_.getBufferPosition(); int off = 0; while (true) { byte b = buf[pos + off]; result |= (int) (b & 0x7f) << shift; if ((b & 0x80) != 0x80) { break; } shift += 7; off++; } trans_.consumeBuffer(off + 1); } else { while (true) { byte b = readByte(); result |= (int) (b & 0x7f) << shift; if ((b & 0x80) != 0x80) { break; } shift += 7; } } return result; } /** * Read an i64 from the wire as a proper varint. The MSB of each byte is set if there is another * byte to follow. This can read up to 10 bytes. */ private long readVarint64() throws TException { int shift = 0; long result = 0; if (trans_.getBytesRemainingInBuffer() >= 10) { byte[] buf = trans_.getBuffer(); int pos = trans_.getBufferPosition(); int off = 0; while (true) { byte b = buf[pos + off]; result |= (long) (b & 0x7f) << shift; if ((b & 0x80) != 0x80) { break; } shift += 7; off++; } trans_.consumeBuffer(off + 1); } else { while (true) { byte b = readByte(); result |= (long) (b & 0x7f) << shift; if ((b & 0x80) != 0x80) { break; } shift += 7; } } return result; } // // encoding helpers // /** Convert from zigzag int to int. */ private int zigzagToInt(int n) { return (n >>> 1) ^ -(n & 1); } /** Convert from zigzag long to long. */ private long zigzagToLong(long n) { return (n >>> 1) ^ -(n & 1); } /** * Note that it's important that the mask bytes are long literals, otherwise they'll default to * ints, and when you shift an int left 56 bits, you just get a messed up int. */ private long bytesToLong(byte[] bytes) { return ((bytes[0] & 0xffL) << 56) | ((bytes[1] & 0xffL) << 48) | ((bytes[2] & 0xffL) << 40) | ((bytes[3] & 0xffL) << 32) | ((bytes[4] & 0xffL) << 24) | ((bytes[5] & 0xffL) << 16) | ((bytes[6] & 0xffL) << 8) | ((bytes[7] & 0xffL)); } /* Little endian version of the above */ private long bytesToLongLE(byte[] bytes) { return ((bytes[7] & 0xffL) << 56) | ((bytes[6] & 0xffL) << 48) | ((bytes[5] & 0xffL) << 40) | ((bytes[4] & 0xffL) << 32) | ((bytes[3] & 0xffL) << 24) | ((bytes[2] & 0xffL) << 16) | ((bytes[1] & 0xffL) << 8) | ((bytes[0] & 0xffL)); } private int bytesToInt(byte[] bytes) { return ((bytes[0] & 0xff) << 24) | ((bytes[1] & 0xff) << 16) | ((bytes[2] & 0xff) << 8) | ((bytes[3] & 0xff)); } // // type testing and converting // private boolean isBoolType(byte b) { int lowerNibble = b & 0x0f; return lowerNibble == Types.BOOLEAN_TRUE || lowerNibble == Types.BOOLEAN_FALSE; } /** Given a TCompactProtocol.Types constant, convert it to its corresponding TType value. */ private byte getTType(byte type) throws TProtocolException { switch ((byte) (type & 0x0f)) { case TType.STOP: return TType.STOP; case Types.BOOLEAN_FALSE: case Types.BOOLEAN_TRUE: return TType.BOOL; case Types.BYTE: return TType.BYTE; case Types.I16: return TType.I16; case Types.I32: return TType.I32; case Types.I64: return TType.I64; case Types.DOUBLE: return TType.DOUBLE; case Types.FLOAT: return TType.FLOAT; case Types.BINARY: return TType.STRING; case Types.LIST: return TType.LIST; case Types.SET: return TType.SET; case Types.MAP: return TType.MAP; case Types.STRUCT: return TType.STRUCT; default: throw new TProtocolException("don't know what type: " + (byte) (type & 0x0f)); } } /** Given a TType value, find the appropriate TCompactProtocol.Types constant. */ private byte getCompactType(byte ttype) { return ttypeToCompactType[ttype]; } @Override protected int typeMinimumSize(byte type) { switch (type & 0x0f) { case TType.BOOL: case TType.BYTE: case TType.I16: // because of variable length encoding case TType.I32: // because of variable length encoding case TType.I64: // because of variable length encoding return 1; case TType.FLOAT: return 4; case TType.DOUBLE: return 8; case TType.STRING: case TType.STRUCT: case TType.MAP: case TType.SET: case TType.LIST: case TType.ENUM: return 1; default: throw new TProtocolException( TProtocolException.INVALID_DATA, "Unexpected data type " + (byte) (type & 0x0f)); } }} |