feat(vanilla): add testing infrastructure and tests (NK-wjnczv)

1 files changed, 444 insertions, 0 deletions

diff --git a/vanilla/node_modules/undici/lib/web/websocket/receiver.js b/vanilla/node_modules/undici/lib/web/websocket/receiver.js
new file mode 100644
index 0000000..ba0a5aa
--- /dev/null
+++ b/vanilla/node_modules/undici/lib/web/websocket/receiver.js
@@ -0,0 +1,444 @@
+'use strict'
+
+const { Writable } = require('node:stream')
+const assert = require('node:assert')
+const { parserStates, opcodes, states, emptyBuffer, sentCloseFrameState } = require('./constants')
+const {
+  isValidStatusCode,
+  isValidOpcode,
+  websocketMessageReceived,
+  utf8Decode,
+  isControlFrame,
+  isTextBinaryFrame,
+  isContinuationFrame
+} = require('./util')
+const { failWebsocketConnection } = require('./connection')
+const { WebsocketFrameSend } = require('./frame')
+const { PerMessageDeflate } = require('./permessage-deflate')
+
+// This code was influenced by ws released under the MIT license.
+// Copyright (c) 2011 Einar Otto Stangvik <einaros@gmail.com>
+// Copyright (c) 2013 Arnout Kazemier and contributors
+// Copyright (c) 2016 Luigi Pinca and contributors
+
+class ByteParser extends Writable {
+  #buffers = []
+  #fragmentsBytes = 0
+  #byteOffset = 0
+  #loop = false
+
+  #state = parserStates.INFO
+
+  #info = {}
+  #fragments = []
+
+  /** @type {Map<string, PerMessageDeflate>} */
+  #extensions
+
+  /** @type {import('./websocket').Handler} */
+  #handler
+
+  constructor (handler, extensions) {
+    super()
+
+    this.#handler = handler
+    this.#extensions = extensions == null ? new Map() : extensions
+
+    if (this.#extensions.has('permessage-deflate')) {
+      this.#extensions.set('permessage-deflate', new PerMessageDeflate(extensions))
+    }
+  }
+
+  /**
+   * @param {Buffer} chunk
+   * @param {() => void} callback
+   */
+  _write (chunk, _, callback) {
+    this.#buffers.push(chunk)
+    this.#byteOffset += chunk.length
+    this.#loop = true
+
+    this.run(callback)
+  }
+
+  /**
+   * Runs whenever a new chunk is received.
+   * Callback is called whenever there are no more chunks buffering,
+   * or not enough bytes are buffered to parse.
+   */
+  run (callback) {
+    while (this.#loop) {
+      if (this.#state === parserStates.INFO) {
+        // If there aren't enough bytes to parse the payload length, etc.
+        if (this.#byteOffset < 2) {
+          return callback()
+        }
+
+        const buffer = this.consume(2)
+        const fin = (buffer[0] & 0x80) !== 0
+        const opcode = buffer[0] & 0x0F
+        const masked = (buffer[1] & 0x80) === 0x80
+
+        const fragmented = !fin && opcode !== opcodes.CONTINUATION
+        const payloadLength = buffer[1] & 0x7F
+
+        const rsv1 = buffer[0] & 0x40
+        const rsv2 = buffer[0] & 0x20
+        const rsv3 = buffer[0] & 0x10
+
+        if (!isValidOpcode(opcode)) {
+          failWebsocketConnection(this.#handler, 1002, 'Invalid opcode received')
+          return callback()
+        }
+
+        if (masked) {
+          failWebsocketConnection(this.#handler, 1002, 'Frame cannot be masked')
+          return callback()
+        }
+
+        // MUST be 0 unless an extension is negotiated that defines meanings
+        // for non-zero values.  If a nonzero value is received and none of
+        // the negotiated extensions defines the meaning of such a nonzero
+        // value, the receiving endpoint MUST _Fail the WebSocket
+        // Connection_.
+        // This document allocates the RSV1 bit of the WebSocket header for
+        // PMCEs and calls the bit the "Per-Message Compressed" bit.  On a
+        // WebSocket connection where a PMCE is in use, this bit indicates
+        // whether a message is compressed or not.
+        if (rsv1 !== 0 && !this.#extensions.has('permessage-deflate')) {
+          failWebsocketConnection(this.#handler, 1002, 'Expected RSV1 to be clear.')
+          return
+        }
+
+        if (rsv2 !== 0 || rsv3 !== 0) {
+          failWebsocketConnection(this.#handler, 1002, 'RSV1, RSV2, RSV3 must be clear')
+          return
+        }
+
+        if (fragmented && !isTextBinaryFrame(opcode)) {
+          // Only text and binary frames can be fragmented
+          failWebsocketConnection(this.#handler, 1002, 'Invalid frame type was fragmented.')
+          return
+        }
+
+        // If we are already parsing a text/binary frame and do not receive either
+        // a continuation frame or close frame, fail the connection.
+        if (isTextBinaryFrame(opcode) && this.#fragments.length > 0) {
+          failWebsocketConnection(this.#handler, 1002, 'Expected continuation frame')
+          return
+        }
+
+        if (this.#info.fragmented && fragmented) {
+          // A fragmented frame can't be fragmented itself
+          failWebsocketConnection(this.#handler, 1002, 'Fragmented frame exceeded 125 bytes.')
+          return
+        }
+
+        // "All control frames MUST have a payload length of 125 bytes or less
+        // and MUST NOT be fragmented."
+        if ((payloadLength > 125 || fragmented) && isControlFrame(opcode)) {
+          failWebsocketConnection(this.#handler, 1002, 'Control frame either too large or fragmented')
+          return
+        }
+
+        if (isContinuationFrame(opcode) && this.#fragments.length === 0 && !this.#info.compressed) {
+          failWebsocketConnection(this.#handler, 1002, 'Unexpected continuation frame')
+          return
+        }
+
+        if (payloadLength <= 125) {
+          this.#info.payloadLength = payloadLength
+          this.#state = parserStates.READ_DATA
+        } else if (payloadLength === 126) {
+          this.#state = parserStates.PAYLOADLENGTH_16
+        } else if (payloadLength === 127) {
+          this.#state = parserStates.PAYLOADLENGTH_64
+        }
+
+        if (isTextBinaryFrame(opcode)) {
+          this.#info.binaryType = opcode
+          this.#info.compressed = rsv1 !== 0
+        }
+
+        this.#info.opcode = opcode
+        this.#info.masked = masked
+        this.#info.fin = fin
+        this.#info.fragmented = fragmented
+      } else if (this.#state === parserStates.PAYLOADLENGTH_16) {
+        if (this.#byteOffset < 2) {
+          return callback()
+        }
+
+        const buffer = this.consume(2)
+
+        this.#info.payloadLength = buffer.readUInt16BE(0)
+        this.#state = parserStates.READ_DATA
+      } else if (this.#state === parserStates.PAYLOADLENGTH_64) {
+        if (this.#byteOffset < 8) {
+          return callback()
+        }
+
+        const buffer = this.consume(8)
+        const upper = buffer.readUInt32BE(0)
+
+        // 2^31 is the maximum bytes an arraybuffer can contain
+        // on 32-bit systems. Although, on 64-bit systems, this is
+        // 2^53-1 bytes.
+        // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_array_length
+        // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/common/globals.h;drc=1946212ac0100668f14eb9e2843bdd846e510a1e;bpv=1;bpt=1;l=1275
+        // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/objects/js-array-buffer.h;l=34;drc=1946212ac0100668f14eb9e2843bdd846e510a1e
+        if (upper > 2 ** 31 - 1) {
+          failWebsocketConnection(this.#handler, 1009, 'Received payload length > 2^31 bytes.')
+          return
+        }
+
+        const lower = buffer.readUInt32BE(4)
+
+        this.#info.payloadLength = (upper << 8) + lower
+        this.#state = parserStates.READ_DATA
+      } else if (this.#state === parserStates.READ_DATA) {
+        if (this.#byteOffset < this.#info.payloadLength) {
+          return callback()
+        }
+
+        const body = this.consume(this.#info.payloadLength)
+
+        if (isControlFrame(this.#info.opcode)) {
+          this.#loop = this.parseControlFrame(body)
+          this.#state = parserStates.INFO
+        } else {
+          if (!this.#info.compressed) {
+            this.writeFragments(body)
+
+            // If the frame is not fragmented, a message has been received.
+            // If the frame is fragmented, it will terminate with a fin bit set
+            // and an opcode of 0 (continuation), therefore we handle that when
+            // parsing continuation frames, not here.
+            if (!this.#info.fragmented && this.#info.fin) {
+              websocketMessageReceived(this.#handler, this.#info.binaryType, this.consumeFragments())
+            }
+
+            this.#state = parserStates.INFO
+          } else {
+            this.#extensions.get('permessage-deflate').decompress(body, this.#info.fin, (error, data) => {
+              if (error) {
+                failWebsocketConnection(this.#handler, 1007, error.message)
+                return
+              }
+
+              this.writeFragments(data)
+
+              if (!this.#info.fin) {
+                this.#state = parserStates.INFO
+                this.#loop = true
+                this.run(callback)
+                return
+              }
+
+              websocketMessageReceived(this.#handler, this.#info.binaryType, this.consumeFragments())
+
+              this.#loop = true
+              this.#state = parserStates.INFO
+              this.run(callback)
+            })
+
+            this.#loop = false
+            break
+          }
+        }
+      }
+    }
+  }
+
+  /**
+   * Take n bytes from the buffered Buffers
+   * @param {number} n
+   * @returns {Buffer}
+   */
+  consume (n) {
+    if (n > this.#byteOffset) {
+      throw new Error('Called consume() before buffers satiated.')
+    } else if (n === 0) {
+      return emptyBuffer
+    }
+
+    this.#byteOffset -= n
+
+    const first = this.#buffers[0]
+
+    if (first.length > n) {
+      // replace with remaining buffer
+      this.#buffers[0] = first.subarray(n, first.length)
+      return first.subarray(0, n)
+    } else if (first.length === n) {
+      // prefect match
+      return this.#buffers.shift()
+    } else {
+      let offset = 0
+      // If Buffer.allocUnsafe is used, extra copies will be made because the offset is non-zero.
+      const buffer = Buffer.allocUnsafeSlow(n)
+      while (offset !== n) {
+        const next = this.#buffers[0]
+        const length = next.length
+
+        if (length + offset === n) {
+          buffer.set(this.#buffers.shift(), offset)
+          break
+        } else if (length + offset > n) {
+          buffer.set(next.subarray(0, n - offset), offset)
+          this.#buffers[0] = next.subarray(n - offset)
+          break
+        } else {
+          buffer.set(this.#buffers.shift(), offset)
+          offset += length
+        }
+      }
+
+      return buffer
+    }
+  }
+
+  writeFragments (fragment) {
+    this.#fragmentsBytes += fragment.length
+    this.#fragments.push(fragment)
+  }
+
+  consumeFragments () {
+    const fragments = this.#fragments
+
+    if (fragments.length === 1) {
+      // single fragment
+      this.#fragmentsBytes = 0
+      return fragments.shift()
+    }
+
+    let offset = 0
+    // If Buffer.allocUnsafe is used, extra copies will be made because the offset is non-zero.
+    const output = Buffer.allocUnsafeSlow(this.#fragmentsBytes)
+
+    for (let i = 0; i < fragments.length; ++i) {
+      const buffer = fragments[i]
+      output.set(buffer, offset)
+      offset += buffer.length
+    }
+
+    this.#fragments = []
+    this.#fragmentsBytes = 0
+
+    return output
+  }
+
+  parseCloseBody (data) {
+    assert(data.length !== 1)
+
+    // https://datatracker.ietf.org/doc/html/rfc6455#section-7.1.5
+    /** @type {number|undefined} */
+    let code
+
+    if (data.length >= 2) {
+      // _The WebSocket Connection Close Code_ is
+      // defined as the status code (Section 7.4) contained in the first Close
+      // control frame received by the application
+      code = data.readUInt16BE(0)
+    }
+
+    if (code !== undefined && !isValidStatusCode(code)) {
+      return { code: 1002, reason: 'Invalid status code', error: true }
+    }
+
+    // https://datatracker.ietf.org/doc/html/rfc6455#section-7.1.6
+    /** @type {Buffer} */
+    let reason = data.subarray(2)
+
+    // Remove BOM
+    if (reason[0] === 0xEF && reason[1] === 0xBB && reason[2] === 0xBF) {
+      reason = reason.subarray(3)
+    }
+
+    try {
+      reason = utf8Decode(reason)
+    } catch {
+      return { code: 1007, reason: 'Invalid UTF-8', error: true }
+    }
+
+    return { code, reason, error: false }
+  }
+
+  /**
+   * Parses control frames.
+   * @param {Buffer} body
+   */
+  parseControlFrame (body) {
+    const { opcode, payloadLength } = this.#info
+
+    if (opcode === opcodes.CLOSE) {
+      if (payloadLength === 1) {
+        failWebsocketConnection(this.#handler, 1002, 'Received close frame with a 1-byte body.')
+        return false
+      }
+
+      this.#info.closeInfo = this.parseCloseBody(body)
+
+      if (this.#info.closeInfo.error) {
+        const { code, reason } = this.#info.closeInfo
+
+        failWebsocketConnection(this.#handler, code, reason)
+        return false
+      }
+
+      // Upon receiving such a frame, the other peer sends a
+      // Close frame in response, if it hasn't already sent one.
+      if (!this.#handler.closeState.has(sentCloseFrameState.SENT) && !this.#handler.closeState.has(sentCloseFrameState.RECEIVED)) {
+        // If an endpoint receives a Close frame and did not previously send a
+        // Close frame, the endpoint MUST send a Close frame in response.  (When
+        // sending a Close frame in response, the endpoint typically echos the
+        // status code it received.)
+        let body = emptyBuffer
+        if (this.#info.closeInfo.code) {
+          body = Buffer.allocUnsafe(2)
+          body.writeUInt16BE(this.#info.closeInfo.code, 0)
+        }
+        const closeFrame = new WebsocketFrameSend(body)
+
+        this.#handler.socket.write(closeFrame.createFrame(opcodes.CLOSE))
+        this.#handler.closeState.add(sentCloseFrameState.SENT)
+      }
+
+      // Upon either sending or receiving a Close control frame, it is said
+      // that _The WebSocket Closing Handshake is Started_ and that the
+      // WebSocket connection is in the CLOSING state.
+      this.#handler.readyState = states.CLOSING
+      this.#handler.closeState.add(sentCloseFrameState.RECEIVED)
+
+      return false
+    } else if (opcode === opcodes.PING) {
+      // Upon receipt of a Ping frame, an endpoint MUST send a Pong frame in
+      // response, unless it already received a Close frame.
+      // A Pong frame sent in response to a Ping frame must have identical
+      // "Application data"
+
+      if (!this.#handler.closeState.has(sentCloseFrameState.RECEIVED)) {
+        const frame = new WebsocketFrameSend(body)
+
+        this.#handler.socket.write(frame.createFrame(opcodes.PONG))
+
+        this.#handler.onPing(body)
+      }
+    } else if (opcode === opcodes.PONG) {
+      // A Pong frame MAY be sent unsolicited.  This serves as a
+      // unidirectional heartbeat.  A response to an unsolicited Pong frame is
+      // not expected.
+      this.#handler.onPong(body)
+    }
+
+    return true
+  }
+
+  get closingInfo () {
+    return this.#info.closeInfo
+  }
+}
+
+module.exports = {
+  ByteParser
+}