+++ /dev/null
-/************************************************************************
- * Copyright 2010-2015 Brian McKelvey.
- *
- * 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.
- ***********************************************************************/
-
-var bufferUtil = require('./BufferUtil').BufferUtil;
-var bufferAllocUnsafe = require('./utils').bufferAllocUnsafe;
-
-const DECODE_HEADER = 1;
-const WAITING_FOR_16_BIT_LENGTH = 2;
-const WAITING_FOR_64_BIT_LENGTH = 3;
-const WAITING_FOR_MASK_KEY = 4;
-const WAITING_FOR_PAYLOAD = 5;
-const COMPLETE = 6;
-
-// WebSocketConnection will pass shared buffer objects for maskBytes and
-// frameHeader into the constructor to avoid tons of small memory allocations
-// for each frame we have to parse. This is only used for parsing frames
-// we receive off the wire.
-function WebSocketFrame(maskBytes, frameHeader, config) {
- this.maskBytes = maskBytes;
- this.frameHeader = frameHeader;
- this.config = config;
- this.maxReceivedFrameSize = config.maxReceivedFrameSize;
- this.protocolError = false;
- this.frameTooLarge = false;
- this.invalidCloseFrameLength = false;
- this.parseState = DECODE_HEADER;
- this.closeStatus = -1;
-}
-
-WebSocketFrame.prototype.addData = function(bufferList) {
- if (this.parseState === DECODE_HEADER) {
- if (bufferList.length >= 2) {
- bufferList.joinInto(this.frameHeader, 0, 0, 2);
- bufferList.advance(2);
- var firstByte = this.frameHeader[0];
- var secondByte = this.frameHeader[1];
-
- this.fin = Boolean(firstByte & 0x80);
- this.rsv1 = Boolean(firstByte & 0x40);
- this.rsv2 = Boolean(firstByte & 0x20);
- this.rsv3 = Boolean(firstByte & 0x10);
- this.mask = Boolean(secondByte & 0x80);
-
- this.opcode = firstByte & 0x0F;
- this.length = secondByte & 0x7F;
-
- // Control frame sanity check
- if (this.opcode >= 0x08) {
- if (this.length > 125) {
- this.protocolError = true;
- this.dropReason = 'Illegal control frame longer than 125 bytes.';
- return true;
- }
- if (!this.fin) {
- this.protocolError = true;
- this.dropReason = 'Control frames must not be fragmented.';
- return true;
- }
- }
-
- if (this.length === 126) {
- this.parseState = WAITING_FOR_16_BIT_LENGTH;
- }
- else if (this.length === 127) {
- this.parseState = WAITING_FOR_64_BIT_LENGTH;
- }
- else {
- this.parseState = WAITING_FOR_MASK_KEY;
- }
- }
- }
- if (this.parseState === WAITING_FOR_16_BIT_LENGTH) {
- if (bufferList.length >= 2) {
- bufferList.joinInto(this.frameHeader, 2, 0, 2);
- bufferList.advance(2);
- this.length = this.frameHeader.readUInt16BE(2);
- this.parseState = WAITING_FOR_MASK_KEY;
- }
- }
- else if (this.parseState === WAITING_FOR_64_BIT_LENGTH) {
- if (bufferList.length >= 8) {
- bufferList.joinInto(this.frameHeader, 2, 0, 8);
- bufferList.advance(8);
- var lengthPair = [
- this.frameHeader.readUInt32BE(2),
- this.frameHeader.readUInt32BE(2+4)
- ];
-
- if (lengthPair[0] !== 0) {
- this.protocolError = true;
- this.dropReason = 'Unsupported 64-bit length frame received';
- return true;
- }
- this.length = lengthPair[1];
- this.parseState = WAITING_FOR_MASK_KEY;
- }
- }
-
- if (this.parseState === WAITING_FOR_MASK_KEY) {
- if (this.mask) {
- if (bufferList.length >= 4) {
- bufferList.joinInto(this.maskBytes, 0, 0, 4);
- bufferList.advance(4);
- this.parseState = WAITING_FOR_PAYLOAD;
- }
- }
- else {
- this.parseState = WAITING_FOR_PAYLOAD;
- }
- }
-
- if (this.parseState === WAITING_FOR_PAYLOAD) {
- if (this.length > this.maxReceivedFrameSize) {
- this.frameTooLarge = true;
- this.dropReason = 'Frame size of ' + this.length.toString(10) +
- ' bytes exceeds maximum accepted frame size';
- return true;
- }
-
- if (this.length === 0) {
- this.binaryPayload = bufferAllocUnsafe(0);
- this.parseState = COMPLETE;
- return true;
- }
- if (bufferList.length >= this.length) {
- this.binaryPayload = bufferList.take(this.length);
- bufferList.advance(this.length);
- if (this.mask) {
- bufferUtil.unmask(this.binaryPayload, this.maskBytes);
- // xor(this.binaryPayload, this.maskBytes, 0);
- }
-
- if (this.opcode === 0x08) { // WebSocketOpcode.CONNECTION_CLOSE
- if (this.length === 1) {
- // Invalid length for a close frame. Must be zero or at least two.
- this.binaryPayload = bufferAllocUnsafe(0);
- this.invalidCloseFrameLength = true;
- }
- if (this.length >= 2) {
- this.closeStatus = this.binaryPayload.readUInt16BE(0);
- this.binaryPayload = this.binaryPayload.slice(2);
- }
- }
-
- this.parseState = COMPLETE;
- return true;
- }
- }
- return false;
-};
-
-WebSocketFrame.prototype.throwAwayPayload = function(bufferList) {
- if (bufferList.length >= this.length) {
- bufferList.advance(this.length);
- this.parseState = COMPLETE;
- return true;
- }
- return false;
-};
-
-WebSocketFrame.prototype.toBuffer = function(nullMask) {
- var maskKey;
- var headerLength = 2;
- var data;
- var outputPos;
- var firstByte = 0x00;
- var secondByte = 0x00;
-
- if (this.fin) {
- firstByte |= 0x80;
- }
- if (this.rsv1) {
- firstByte |= 0x40;
- }
- if (this.rsv2) {
- firstByte |= 0x20;
- }
- if (this.rsv3) {
- firstByte |= 0x10;
- }
- if (this.mask) {
- secondByte |= 0x80;
- }
-
- firstByte |= (this.opcode & 0x0F);
-
- // the close frame is a special case because the close reason is
- // prepended to the payload data.
- if (this.opcode === 0x08) {
- this.length = 2;
- if (this.binaryPayload) {
- this.length += this.binaryPayload.length;
- }
- data = bufferAllocUnsafe(this.length);
- data.writeUInt16BE(this.closeStatus, 0);
- if (this.length > 2) {
- this.binaryPayload.copy(data, 2);
- }
- }
- else if (this.binaryPayload) {
- data = this.binaryPayload;
- this.length = data.length;
- }
- else {
- this.length = 0;
- }
-
- if (this.length <= 125) {
- // encode the length directly into the two-byte frame header
- secondByte |= (this.length & 0x7F);
- }
- else if (this.length > 125 && this.length <= 0xFFFF) {
- // Use 16-bit length
- secondByte |= 126;
- headerLength += 2;
- }
- else if (this.length > 0xFFFF) {
- // Use 64-bit length
- secondByte |= 127;
- headerLength += 8;
- }
-
- var output = bufferAllocUnsafe(this.length + headerLength + (this.mask ? 4 : 0));
-
- // write the frame header
- output[0] = firstByte;
- output[1] = secondByte;
-
- outputPos = 2;
-
- if (this.length > 125 && this.length <= 0xFFFF) {
- // write 16-bit length
- output.writeUInt16BE(this.length, outputPos);
- outputPos += 2;
- }
- else if (this.length > 0xFFFF) {
- // write 64-bit length
- output.writeUInt32BE(0x00000000, outputPos);
- output.writeUInt32BE(this.length, outputPos + 4);
- outputPos += 8;
- }
-
- if (this.mask) {
- maskKey = nullMask ? 0 : ((Math.random() * 0xFFFFFFFF) >>> 0);
- this.maskBytes.writeUInt32BE(maskKey, 0);
-
- // write the mask key
- this.maskBytes.copy(output, outputPos);
- outputPos += 4;
-
- if (data) {
- bufferUtil.mask(data, this.maskBytes, output, outputPos, this.length);
- }
- }
- else if (data) {
- data.copy(output, outputPos);
- }
-
- return output;
-};
-
-WebSocketFrame.prototype.toString = function() {
- return 'Opcode: ' + this.opcode + ', fin: ' + this.fin + ', length: ' + this.length + ', hasPayload: ' + Boolean(this.binaryPayload) + ', masked: ' + this.mask;
-};
-
-
-module.exports = WebSocketFrame;