Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1166 insertions, 0 deletions

diff --git a/testing/xpcshell/node-http2/lib/protocol/framer.js b/testing/xpcshell/node-http2/lib/protocol/framer.js
new file mode 100644
index 0000000000..055402f8d8
--- /dev/null
+++ b/testing/xpcshell/node-http2/lib/protocol/framer.js
@@ -0,0 +1,1166 @@
+// The framer consists of two [Transform Stream][1] subclasses that operate in [object mode][2]:
+// the Serializer and the Deserializer
+// [1]: https://nodejs.org/api/stream.html#stream_class_stream_transform
+// [2]: https://nodejs.org/api/stream.html#stream_new_stream_readable_options
+var assert = require('assert');
+
+var Transform = require('stream').Transform;
+
+exports.Serializer = Serializer;
+exports.Deserializer = Deserializer;
+
+var logData = Boolean(process.env.HTTP2_LOG_DATA);
+
+var MAX_PAYLOAD_SIZE = 16384;
+var WINDOW_UPDATE_PAYLOAD_SIZE = 4;
+
+// Serializer
+// ----------
+//
+//     Frame Objects
+//     * * * * * * * --+---------------------------
+//                     |                          |
+//                     v                          v           Buffers
+//      [] -----> Payload Ser. --[buffers]--> Header Ser. --> * * * *
+//     empty      adds payload                adds header
+//     array        buffers                     buffer
+
+function Serializer(log) {
+  this._log = log.child({ component: 'serializer' });
+  Transform.call(this, { objectMode: true });
+}
+Serializer.prototype = Object.create(Transform.prototype, { constructor: { value: Serializer } });
+
+// When there's an incoming frame object, it first generates the frame type specific part of the
+// frame (payload), and then then adds the header part which holds fields that are common to all
+// frame types (like the length of the payload).
+Serializer.prototype._transform = function _transform(frame, encoding, done) {
+  this._log.trace({ frame: frame }, 'Outgoing frame');
+
+  assert(frame.type in Serializer, 'Unknown frame type: ' + frame.type);
+
+  var buffers = [];
+  Serializer[frame.type](frame, buffers);
+  var length = Serializer.commonHeader(frame, buffers);
+
+  assert(length <= MAX_PAYLOAD_SIZE, 'Frame too large!');
+
+  for (var i = 0; i < buffers.length; i++) {
+    if (logData) {
+      this._log.trace({ data: buffers[i] }, 'Outgoing data');
+    }
+    this.push(buffers[i]);
+  }
+
+  done();
+};
+
+// Deserializer
+// ------------
+//
+//     Buffers
+//     * * * * --------+-------------------------
+//                     |                        |
+//                     v                        v           Frame Objects
+//      {} -----> Header Des. --{frame}--> Payload Des. --> * * * * * * *
+//     empty      adds parsed              adds parsed
+//     object  header properties        payload properties
+
+function Deserializer(log, role) {
+  this._role = role;
+  this._log = log.child({ component: 'deserializer' });
+  Transform.call(this, { objectMode: true });
+  this._next(COMMON_HEADER_SIZE);
+}
+Deserializer.prototype = Object.create(Transform.prototype, { constructor: { value: Deserializer } });
+
+// The Deserializer is stateful, and it's two main alternating states are: *waiting for header* and
+// *waiting for payload*. The state is stored in the boolean property `_waitingForHeader`.
+//
+// When entering a new state, a `_buffer` is created that will hold the accumulated data (header or
+// payload). The `_cursor` is used to track the progress.
+Deserializer.prototype._next = function(size) {
+  this._cursor = 0;
+  this._buffer = Buffer.alloc(size);
+  this._waitingForHeader = !this._waitingForHeader;
+  if (this._waitingForHeader) {
+    this._frame = {};
+  }
+};
+
+// Parsing an incoming buffer is an iterative process because it can hold multiple frames if it's
+// large enough. A `cursor` is used to track the progress in parsing the incoming `chunk`.
+Deserializer.prototype._transform = function _transform(chunk, encoding, done) {
+  var cursor = 0;
+
+  if (logData) {
+    this._log.trace({ data: chunk }, 'Incoming data');
+  }
+
+  while(cursor < chunk.length) {
+    // The content of an incoming buffer is first copied to `_buffer`. If it can't hold the full
+    // chunk, then only a part of it is copied.
+    var toCopy = Math.min(chunk.length - cursor, this._buffer.length - this._cursor);
+    chunk.copy(this._buffer, this._cursor, cursor, cursor + toCopy);
+    this._cursor += toCopy;
+    cursor += toCopy;
+
+    // When `_buffer` is full, it's content gets parsed either as header or payload depending on
+    // the actual state.
+
+    // If it's header then the parsed data is stored in a temporary variable and then the
+    // deserializer waits for the specified length payload.
+    if ((this._cursor === this._buffer.length) && this._waitingForHeader) {
+      var payloadSize = Deserializer.commonHeader(this._buffer, this._frame);
+      if (payloadSize <= MAX_PAYLOAD_SIZE) {
+        this._next(payloadSize);
+      } else {
+        this.emit('error', 'FRAME_SIZE_ERROR');
+        return;
+      }
+    }
+
+    // If it's payload then the the frame object is finalized and then gets pushed out.
+    // Unknown frame types are ignored.
+    //
+    // Note: If we just finished the parsing of a header and the payload length is 0, this branch
+    // will also run.
+    if ((this._cursor === this._buffer.length) && !this._waitingForHeader) {
+      if (this._frame.type) {
+        var error = Deserializer[this._frame.type](this._buffer, this._frame, this._role);
+        if (error) {
+          this._log.error('Incoming frame parsing error: ' + error);
+          this.emit('error', error);
+        } else {
+          this._log.trace({ frame: this._frame }, 'Incoming frame');
+          this.push(this._frame);
+        }
+      } else {
+        this._log.error('Unknown type incoming frame');
+        // Ignore it other than logging
+      }
+      this._next(COMMON_HEADER_SIZE);
+    }
+  }
+
+  done();
+};
+
+// [Frame Header](https://tools.ietf.org/html/rfc7540#section-4.1)
+// --------------------------------------------------------------
+//
+// HTTP/2 frames share a common base format consisting of a 9-byte header followed by 0 to 2^24 - 1
+// bytes of data.
+//
+// Additional size limits can be set by specific application uses. HTTP limits the frame size to
+// 16,384 octets by default, though this can be increased by a receiver.
+//
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |                 Length (24)                   |
+//     +---------------+---------------+---------------+
+//     |   Type (8)    |   Flags (8)   |
+//     +-+-----------------------------+---------------+---------------+
+//     |R|                 Stream Identifier (31)                      |
+//     +-+-------------------------------------------------------------+
+//     |                     Frame Data (0...)                       ...
+//     +---------------------------------------------------------------+
+//
+// The fields of the frame header are defined as:
+//
+// * Length:
+//   The length of the frame data expressed as an unsigned 24-bit integer. The 9 bytes of the frame
+//   header are not included in this value.
+//
+// * Type:
+//   The 8-bit type of the frame. The frame type determines how the remainder of the frame header
+//   and data are interpreted. Implementations MUST ignore unsupported and unrecognized frame types.
+//
+// * Flags:
+//   An 8-bit field reserved for frame-type specific boolean flags.
+//
+//   Flags are assigned semantics specific to the indicated frame type. Flags that have no defined
+//   semantics for a particular frame type MUST be ignored, and MUST be left unset (0) when sending.
+//
+// * R:
+//   A reserved 1-bit field. The semantics of this bit are undefined and the bit MUST remain unset
+//   (0) when sending and MUST be ignored when receiving.
+//
+// * Stream Identifier:
+//   A 31-bit stream identifier. The value 0 is reserved for frames that are associated with the
+//   connection as a whole as opposed to an individual stream.
+//
+// The structure and content of the remaining frame data is dependent entirely on the frame type.
+
+var COMMON_HEADER_SIZE = 9;
+
+var frameTypes = [];
+
+var frameFlags = {};
+
+var genericAttributes = ['type', 'flags', 'stream'];
+
+var typeSpecificAttributes = {};
+
+Serializer.commonHeader = function writeCommonHeader(frame, buffers) {
+  var headerBuffer = Buffer.alloc(COMMON_HEADER_SIZE);
+
+  var size = 0;
+  for (var i = 0; i < buffers.length; i++) {
+    size += buffers[i].length;
+  }
+  headerBuffer.writeUInt8(0, 0);
+  headerBuffer.writeUInt16BE(size, 1);
+
+  var typeId = frameTypes.indexOf(frame.type);  // If we are here then the type is valid for sure
+  headerBuffer.writeUInt8(typeId, 3);
+
+  var flagByte = 0;
+  for (var flag in frame.flags) {
+    var position = frameFlags[frame.type].indexOf(flag);
+    assert(position !== -1, 'Unknown flag for frame type ' + frame.type + ': ' + flag);
+    if (frame.flags[flag]) {
+      flagByte |= (1 << position);
+    }
+  }
+  headerBuffer.writeUInt8(flagByte, 4);
+
+  assert((0 <= frame.stream) && (frame.stream < 0x7fffffff), frame.stream);
+  headerBuffer.writeUInt32BE(frame.stream || 0, 5);
+
+  buffers.unshift(headerBuffer);
+
+  return size;
+};
+
+Deserializer.commonHeader = function readCommonHeader(buffer, frame) {
+  if (buffer.length < 9) {
+    return 'FRAME_SIZE_ERROR';
+  }
+
+  var totallyWastedByte = buffer.readUInt8(0);
+  var length = buffer.readUInt16BE(1);
+  // We do this just for sanity checking later on, to make sure no one sent us a
+  // frame that's super large.
+  length += totallyWastedByte << 16;
+
+  frame.type = frameTypes[buffer.readUInt8(3)];
+  if (!frame.type) {
+    // We are required to ignore unknown frame types
+    return length;
+  }
+
+  frame.flags = {};
+  var flagByte = buffer.readUInt8(4);
+  var definedFlags = frameFlags[frame.type];
+  for (var i = 0; i < definedFlags.length; i++) {
+    frame.flags[definedFlags[i]] = Boolean(flagByte & (1 << i));
+  }
+
+  frame.stream = buffer.readUInt32BE(5) & 0x7fffffff;
+
+  return length;
+};
+
+// Frame types
+// ===========
+
+// Every frame type is registered in the following places:
+//
+// * `frameTypes`: a register of frame type codes (used by `commonHeader()`)
+// * `frameFlags`: a register of valid flags for frame types (used by `commonHeader()`)
+// * `typeSpecificAttributes`: a register of frame specific frame object attributes (used by
+//   logging code and also serves as documentation for frame objects)
+
+// [DATA Frames](https://tools.ietf.org/html/rfc7540#section-6.1)
+// ------------------------------------------------------------
+//
+// DATA frames (type=0x0) convey arbitrary, variable-length sequences of octets associated with a
+// stream.
+//
+// The DATA frame defines the following flags:
+//
+// * END_STREAM (0x1):
+//   Bit 1 being set indicates that this frame is the last that the endpoint will send for the
+//   identified stream.
+// * PADDED (0x08):
+//   Bit 4 being set indicates that the Pad Length field is present.
+
+frameTypes[0x0] = 'DATA';
+
+frameFlags.DATA = ['END_STREAM', 'RESERVED2', 'RESERVED4', 'PADDED'];
+
+typeSpecificAttributes.DATA = ['data'];
+
+Serializer.DATA = function writeData(frame, buffers) {
+  buffers.push(frame.data);
+};
+
+Deserializer.DATA = function readData(buffer, frame) {
+  var dataOffset = 0;
+  var paddingLength = 0;
+  if (frame.flags.PADDED) {
+    if (buffer.length < 1) {
+      // We must have at least one byte for padding control, but we don't. Bad peer!
+      return 'FRAME_SIZE_ERROR';
+    }
+    paddingLength = (buffer.readUInt8(dataOffset) & 0xff);
+    dataOffset = 1;
+  }
+
+  if (paddingLength) {
+    if (paddingLength >= (buffer.length - 1)) {
+      // We don't have enough room for the padding advertised - bad peer!
+      return 'FRAME_SIZE_ERROR';
+    }
+    frame.data = buffer.slice(dataOffset, -1 * paddingLength);
+  } else {
+    frame.data = buffer.slice(dataOffset);
+  }
+};
+
+// [HEADERS](https://tools.ietf.org/html/rfc7540#section-6.2)
+// --------------------------------------------------------------
+//
+// The HEADERS frame (type=0x1) allows the sender to create a stream.
+//
+// The HEADERS frame defines the following flags:
+//
+// * END_STREAM (0x1):
+//   Bit 1 being set indicates that this frame is the last that the endpoint will send for the
+//   identified stream.
+// * END_HEADERS (0x4):
+//   The END_HEADERS bit indicates that this frame contains the entire payload necessary to provide
+//   a complete set of headers.
+// * PADDED (0x08):
+//   Bit 4 being set indicates that the Pad Length field is present.
+// * PRIORITY (0x20):
+//   Bit 6 being set indicates that the Exlusive Flag (E), Stream Dependency, and Weight fields are
+//   present.
+
+frameTypes[0x1] = 'HEADERS';
+
+frameFlags.HEADERS = ['END_STREAM', 'RESERVED2', 'END_HEADERS', 'PADDED', 'RESERVED5', 'PRIORITY'];
+
+typeSpecificAttributes.HEADERS = ['priorityDependency', 'priorityWeight', 'exclusiveDependency', 'headers', 'data'];
+
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |Pad Length? (8)|
+//     +-+-------------+---------------+-------------------------------+
+//     |E|                 Stream Dependency? (31)                     |
+//     +-+-------------+-----------------------------------------------+
+//     |  Weight? (8)  |
+//     +-+-------------+-----------------------------------------------+
+//     |                   Header Block Fragment (*)                 ...
+//     +---------------------------------------------------------------+
+//     |                           Padding (*)                       ...
+//     +---------------------------------------------------------------+
+//
+// The payload of a HEADERS frame contains a Headers Block
+
+Serializer.HEADERS = function writeHeadersPriority(frame, buffers) {
+  if (frame.flags.PRIORITY) {
+    var buffer = Buffer.alloc(5);
+    assert((0 <= frame.priorityDependency) && (frame.priorityDependency <= 0x7fffffff), frame.priorityDependency);
+    buffer.writeUInt32BE(frame.priorityDependency, 0);
+    if (frame.exclusiveDependency) {
+      buffer[0] |= 0x80;
+    }
+    assert((0 <= frame.priorityWeight) && (frame.priorityWeight <= 0xff), frame.priorityWeight);
+    buffer.writeUInt8(frame.priorityWeight, 4);
+    buffers.push(buffer);
+  }
+  buffers.push(frame.data);
+};
+
+Deserializer.HEADERS = function readHeadersPriority(buffer, frame) {
+  var minFrameLength = 0;
+  if (frame.flags.PADDED) {
+    minFrameLength += 1;
+  }
+  if (frame.flags.PRIORITY) {
+    minFrameLength += 5;
+  }
+  if (buffer.length < minFrameLength) {
+    // Peer didn't send enough data - bad peer!
+    return 'FRAME_SIZE_ERROR';
+  }
+
+  var dataOffset = 0;
+  var paddingLength = 0;
+  if (frame.flags.PADDED) {
+    paddingLength = (buffer.readUInt8(dataOffset) & 0xff);
+    dataOffset = 1;
+  }
+
+  if (frame.flags.PRIORITY) {
+    var dependencyData = Buffer.alloc(4);
+    buffer.copy(dependencyData, 0, dataOffset, dataOffset + 4);
+    dataOffset += 4;
+    frame.exclusiveDependency = !!(dependencyData[0] & 0x80);
+    dependencyData[0] &= 0x7f;
+    frame.priorityDependency = dependencyData.readUInt32BE(0);
+    frame.priorityWeight = buffer.readUInt8(dataOffset);
+    dataOffset += 1;
+  }
+
+  if (paddingLength) {
+    if ((buffer.length - dataOffset) < paddingLength) {
+      // Not enough data left to satisfy the advertised padding - bad peer!
+      return 'FRAME_SIZE_ERROR';
+    }
+    frame.data = buffer.slice(dataOffset, -1 * paddingLength);
+  } else {
+    frame.data = buffer.slice(dataOffset);
+  }
+};
+
+// [PRIORITY](https://tools.ietf.org/html/rfc7540#section-6.3)
+// -------------------------------------------------------
+//
+// The PRIORITY frame (type=0x2) specifies the sender-advised priority of a stream.
+//
+// The PRIORITY frame does not define any flags.
+
+frameTypes[0x2] = 'PRIORITY';
+
+frameFlags.PRIORITY = [];
+
+typeSpecificAttributes.PRIORITY = ['priorityDependency', 'priorityWeight', 'exclusiveDependency'];
+
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |E|                 Stream Dependency? (31)                     |
+//     +-+-------------+-----------------------------------------------+
+//     |  Weight? (8)  |
+//     +-+-------------+
+//
+// The payload of a PRIORITY frame contains an exclusive bit, a 31-bit dependency, and an 8-bit weight
+
+Serializer.PRIORITY = function writePriority(frame, buffers) {
+  var buffer = Buffer.alloc(5);
+  assert((0 <= frame.priorityDependency) && (frame.priorityDependency <= 0x7fffffff), frame.priorityDependency);
+  buffer.writeUInt32BE(frame.priorityDependency, 0);
+  if (frame.exclusiveDependency) {
+    buffer[0] |= 0x80;
+  }
+  assert((0 <= frame.priorityWeight) && (frame.priorityWeight <= 0xff), frame.priorityWeight);
+  buffer.writeUInt8(frame.priorityWeight, 4);
+
+  buffers.push(buffer);
+};
+
+Deserializer.PRIORITY = function readPriority(buffer, frame) {
+  if (buffer.length < 5) {
+    // PRIORITY frames are 5 bytes long. Bad peer!
+    return 'FRAME_SIZE_ERROR';
+  }
+  var dependencyData = Buffer.alloc(4);
+  buffer.copy(dependencyData, 0, 0, 4);
+  frame.exclusiveDependency = !!(dependencyData[0] & 0x80);
+  dependencyData[0] &= 0x7f;
+  frame.priorityDependency = dependencyData.readUInt32BE(0);
+  frame.priorityWeight = buffer.readUInt8(4);
+};
+
+// [RST_STREAM](https://tools.ietf.org/html/rfc7540#section-6.4)
+// -----------------------------------------------------------
+//
+// The RST_STREAM frame (type=0x3) allows for abnormal termination of a stream.
+//
+// No type-flags are defined.
+
+frameTypes[0x3] = 'RST_STREAM';
+
+frameFlags.RST_STREAM = [];
+
+typeSpecificAttributes.RST_STREAM = ['error'];
+
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |                         Error Code (32)                       |
+//     +---------------------------------------------------------------+
+//
+// The RST_STREAM frame contains a single unsigned, 32-bit integer identifying the error
+// code (see Error Codes). The error code indicates why the stream is being terminated.
+
+Serializer.RST_STREAM = function writeRstStream(frame, buffers) {
+  var buffer = Buffer.alloc(4);
+  var code = errorCodes.indexOf(frame.error);
+  assert((0 <= code) && (code <= 0xffffffff), code);
+  buffer.writeUInt32BE(code, 0);
+  buffers.push(buffer);
+};
+
+Deserializer.RST_STREAM = function readRstStream(buffer, frame) {
+  if (buffer.length < 4) {
+    // RST_STREAM is 4 bytes long. Bad peer!
+    return 'FRAME_SIZE_ERROR';
+  }
+  frame.error = errorCodes[buffer.readUInt32BE(0)];
+  if (!frame.error) {
+    // Unknown error codes are considered equivalent to INTERNAL_ERROR
+    frame.error = 'INTERNAL_ERROR';
+  }
+};
+
+// [SETTINGS](https://tools.ietf.org/html/rfc7540#section-6.5)
+// -------------------------------------------------------
+//
+// The SETTINGS frame (type=0x4) conveys configuration parameters that affect how endpoints
+// communicate.
+//
+// The SETTINGS frame defines the following flag:
+
+// * ACK (0x1):
+//   Bit 1 being set indicates that this frame acknowledges receipt and application of the peer's
+//   SETTINGS frame.
+frameTypes[0x4] = 'SETTINGS';
+
+frameFlags.SETTINGS = ['ACK'];
+
+typeSpecificAttributes.SETTINGS = ['settings'];
+
+// The payload of a SETTINGS frame consists of zero or more settings. Each setting consists of a
+// 16-bit identifier, and an unsigned 32-bit value.
+//
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |         Identifier(16)          |        Value (32)           |
+//     +-----------------+---------------------------------------------+
+//     ...Value                          |
+//     +---------------------------------+
+//
+// Each setting in a SETTINGS frame replaces the existing value for that setting.  Settings are
+// processed in the order in which they appear, and a receiver of a SETTINGS frame does not need to
+// maintain any state other than the current value of settings.  Therefore, the value of a setting
+// is the last value that is seen by a receiver. This permits the inclusion of the same settings
+// multiple times in the same SETTINGS frame, though doing so does nothing other than waste
+// connection capacity.
+
+Serializer.SETTINGS = function writeSettings(frame, buffers) {
+  var settings = [], settingsLeft = Object.keys(frame.settings);
+  definedSettings.forEach(function(setting, id) {
+    if (setting.name in frame.settings) {
+      settingsLeft.splice(settingsLeft.indexOf(setting.name), 1);
+      var value = frame.settings[setting.name];
+      settings.push({ id: id, value: setting.flag ? Boolean(value) : value });
+    }
+  });
+  assert(settingsLeft.length === 0, 'Unknown settings: ' + settingsLeft.join(', '));
+
+  var buffer = Buffer.alloc(settings.length * 6);
+  for (var i = 0; i < settings.length; i++) {
+    buffer.writeUInt16BE(settings[i].id & 0xffff, i*6);
+    buffer.writeUInt32BE(settings[i].value, i*6 + 2);
+  }
+
+  buffers.push(buffer);
+};
+
+Deserializer.SETTINGS = function readSettings(buffer, frame, role) {
+  frame.settings = {};
+
+  // Receipt of a SETTINGS frame with the ACK flag set and a length
+  // field value other than 0 MUST be treated as a connection error
+  // (Section 5.4.1) of type FRAME_SIZE_ERROR.
+  if(frame.flags.ACK && buffer.length != 0) {
+    return 'FRAME_SIZE_ERROR';
+  }
+
+  if (buffer.length % 6 !== 0) {
+    return 'PROTOCOL_ERROR';
+  }
+  for (var i = 0; i < buffer.length / 6; i++) {
+    var id = buffer.readUInt16BE(i*6) & 0xffff;
+    var setting = definedSettings[id];
+    if (setting) {
+      if (role == 'CLIENT' && setting.name == 'SETTINGS_ENABLE_PUSH') {
+        return 'SETTINGS frame on client got SETTINGS_ENABLE_PUSH';
+      }
+      var value = buffer.readUInt32BE(i*6 + 2);
+      frame.settings[setting.name] = setting.flag ? Boolean(value & 0x1) : value;
+    }
+  }
+};
+
+// The following settings are defined:
+var definedSettings = [];
+
+// * SETTINGS_HEADER_TABLE_SIZE (1):
+//   Allows the sender to inform the remote endpoint of the size of the header compression table
+//   used to decode header blocks.
+definedSettings[1] = { name: 'SETTINGS_HEADER_TABLE_SIZE', flag: false };
+
+// * SETTINGS_ENABLE_PUSH (2):
+//   This setting can be use to disable server push. An endpoint MUST NOT send a PUSH_PROMISE frame
+//   if it receives this setting set to a value of 0. The default value is 1, which indicates that
+//   push is permitted.
+definedSettings[2] = { name: 'SETTINGS_ENABLE_PUSH', flag: true };
+
+// * SETTINGS_MAX_CONCURRENT_STREAMS (3):
+//   indicates the maximum number of concurrent streams that the sender will allow.
+definedSettings[3] = { name: 'SETTINGS_MAX_CONCURRENT_STREAMS', flag: false };
+
+// * SETTINGS_INITIAL_WINDOW_SIZE (4):
+//   indicates the sender's initial stream window size (in bytes) for new streams.
+definedSettings[4] = { name: 'SETTINGS_INITIAL_WINDOW_SIZE', flag: false };
+
+// * SETTINGS_MAX_FRAME_SIZE (5):
+//   indicates the maximum size of a frame the receiver will allow.
+definedSettings[5] = { name: 'SETTINGS_MAX_FRAME_SIZE', flag: false };
+
+// [PUSH_PROMISE](https://tools.ietf.org/html/rfc7540#section-6.6)
+// ---------------------------------------------------------------
+//
+// The PUSH_PROMISE frame (type=0x5) is used to notify the peer endpoint in advance of streams the
+// sender intends to initiate.
+//
+// The PUSH_PROMISE frame defines the following flags:
+//
+// * END_PUSH_PROMISE (0x4):
+//   The END_PUSH_PROMISE bit indicates that this frame contains the entire payload necessary to
+//   provide a complete set of headers.
+
+frameTypes[0x5] = 'PUSH_PROMISE';
+
+frameFlags.PUSH_PROMISE = ['RESERVED1', 'RESERVED2', 'END_PUSH_PROMISE', 'PADDED'];
+
+typeSpecificAttributes.PUSH_PROMISE = ['promised_stream', 'headers', 'data'];
+
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |Pad Length? (8)|
+//     +-+-------------+-----------------------------------------------+
+//     |X|                Promised-Stream-ID (31)                      |
+//     +-+-------------------------------------------------------------+
+//     |                 Header Block Fragment (*)                   ...
+//     +---------------------------------------------------------------+
+//     |                         Padding (*)                         ...
+//     +---------------------------------------------------------------+
+//
+// The PUSH_PROMISE frame includes the unsigned 31-bit identifier of
+// the stream the endpoint plans to create along with a minimal set of headers that provide
+// additional context for the stream.
+
+Serializer.PUSH_PROMISE = function writePushPromise(frame, buffers) {
+  var buffer = Buffer.alloc(4);
+
+  var promised_stream = frame.promised_stream;
+  assert((0 <= promised_stream) && (promised_stream <= 0x7fffffff), promised_stream);
+  buffer.writeUInt32BE(promised_stream, 0);
+
+  buffers.push(buffer);
+  buffers.push(frame.data);
+};
+
+Deserializer.PUSH_PROMISE = function readPushPromise(buffer, frame) {
+  if (buffer.length < 4) {
+    return 'FRAME_SIZE_ERROR';
+  }
+  var dataOffset = 0;
+  var paddingLength = 0;
+  if (frame.flags.PADDED) {
+    if (buffer.length < 5) {
+      return 'FRAME_SIZE_ERROR';
+    }
+    paddingLength = (buffer.readUInt8(dataOffset) & 0xff);
+    dataOffset = 1;
+  }
+  frame.promised_stream = buffer.readUInt32BE(dataOffset) & 0x7fffffff;
+  dataOffset += 4;
+  if (paddingLength) {
+    if ((buffer.length - dataOffset) < paddingLength) {
+      return 'FRAME_SIZE_ERROR';
+    }
+    frame.data = buffer.slice(dataOffset, -1 * paddingLength);
+  } else {
+    frame.data = buffer.slice(dataOffset);
+  }
+};
+
+// [PING](https://tools.ietf.org/html/rfc7540#section-6.7)
+// -----------------------------------------------
+//
+// The PING frame (type=0x6) is a mechanism for measuring a minimal round-trip time from the
+// sender, as well as determining whether an idle connection is still functional.
+//
+// The PING frame defines one type-specific flag:
+//
+// * ACK (0x1):
+//   Bit 1 being set indicates that this PING frame is a PING response.
+
+frameTypes[0x6] = 'PING';
+
+frameFlags.PING = ['ACK'];
+
+typeSpecificAttributes.PING = ['data'];
+
+// In addition to the frame header, PING frames MUST contain 8 additional octets of opaque data.
+
+Serializer.PING = function writePing(frame, buffers) {
+  buffers.push(frame.data);
+};
+
+Deserializer.PING = function readPing(buffer, frame) {
+  if (buffer.length !== 8) {
+    return 'FRAME_SIZE_ERROR';
+  }
+  frame.data = buffer;
+};
+
+// [GOAWAY](https://tools.ietf.org/html/rfc7540#section-6.8)
+// ---------------------------------------------------
+//
+// The GOAWAY frame (type=0x7) informs the remote peer to stop creating streams on this connection.
+//
+// The GOAWAY frame does not define any flags.
+
+frameTypes[0x7] = 'GOAWAY';
+
+frameFlags.GOAWAY = [];
+
+typeSpecificAttributes.GOAWAY = ['last_stream', 'error'];
+
+//      0                   1                   2                   3
+//      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//     |X|                  Last-Stream-ID (31)                        |
+//     +-+-------------------------------------------------------------+
+//     |                      Error Code (32)                          |
+//     +---------------------------------------------------------------+
+//
+// The last stream identifier in the GOAWAY frame contains the highest numbered stream identifier
+// for which the sender of the GOAWAY frame has received frames on and might have taken some action
+// on.
+//
+// The GOAWAY frame also contains a 32-bit error code (see Error Codes) that contains the reason for
+// closing the connection.
+
+Serializer.GOAWAY = function writeGoaway(frame, buffers) {
+  var buffer = Buffer.alloc(8);
+
+  var last_stream = frame.last_stream;
+  assert((0 <= last_stream) && (last_stream <= 0x7fffffff), last_stream);
+  buffer.writeUInt32BE(last_stream, 0);
+
+  var code = errorCodes.indexOf(frame.error);
+  assert((0 <= code) && (code <= 0xffffffff), code);
+  buffer.writeUInt32BE(code, 4);
+
+  buffers.push(buffer);
+};
+
+Deserializer.GOAWAY = function readGoaway(buffer, frame) {
+  if (buffer.length !== 8) {
+    // GOAWAY must have 8 bytes
+    return 'FRAME_SIZE_ERROR';
+  }
+  frame.last_stream = buffer.readUInt32BE(0) & 0x7fffffff;
+  frame.error = errorCodes[buffer.readUInt32BE(4)];
+  if (!frame.error) {
+    // Unknown error types are to be considered equivalent to INTERNAL ERROR
+    frame.error = 'INTERNAL_ERROR';
+  }
+};
+
+// [WINDOW_UPDATE](https://tools.ietf.org/html/rfc7540#section-6.9)
+// -----------------------------------------------------------------
+//
+// The WINDOW_UPDATE frame (type=0x8) is used to implement flow control.
+//
+// The WINDOW_UPDATE frame does not define any flags.
+
+frameTypes[0x8] = 'WINDOW_UPDATE';
+
+frameFlags.WINDOW_UPDATE = [];
+
+typeSpecificAttributes.WINDOW_UPDATE = ['window_size'];
+
+// The payload of a WINDOW_UPDATE frame is a 32-bit value indicating the additional number of bytes
+// that the sender can transmit in addition to the existing flow control window. The legal range
+// for this field is 1 to 2^31 - 1 (0x7fffffff) bytes; the most significant bit of this value is
+// reserved.
+
+Serializer.WINDOW_UPDATE = function writeWindowUpdate(frame, buffers) {
+  var buffer = Buffer.alloc(4);
+
+  var window_size = frame.window_size;
+  assert((0 < window_size) && (window_size <= 0x7fffffff), window_size);
+  buffer.writeUInt32BE(window_size, 0);
+
+  buffers.push(buffer);
+};
+
+Deserializer.WINDOW_UPDATE = function readWindowUpdate(buffer, frame) {
+  if (buffer.length !== WINDOW_UPDATE_PAYLOAD_SIZE) {
+    return 'FRAME_SIZE_ERROR';
+  }
+  frame.window_size = buffer.readUInt32BE(0) & 0x7fffffff;
+  if (frame.window_size === 0) {
+    return 'PROTOCOL_ERROR';
+  }
+};
+
+// [CONTINUATION](https://tools.ietf.org/html/rfc7540#section-6.10)
+// ------------------------------------------------------------
+//
+// The CONTINUATION frame (type=0x9) is used to continue a sequence of header block fragments.
+//
+// The CONTINUATION frame defines the following flag:
+//
+// * END_HEADERS (0x4):
+//   The END_HEADERS bit indicates that this frame ends the sequence of header block fragments
+//   necessary to provide a complete set of headers.
+
+frameTypes[0x9] = 'CONTINUATION';
+
+frameFlags.CONTINUATION = ['RESERVED1', 'RESERVED2', 'END_HEADERS'];
+
+typeSpecificAttributes.CONTINUATION = ['headers', 'data'];
+
+Serializer.CONTINUATION = function writeContinuation(frame, buffers) {
+  buffers.push(frame.data);
+};
+
+Deserializer.CONTINUATION = function readContinuation(buffer, frame) {
+  frame.data = buffer;
+};
+
+// [ALTSVC](https://tools.ietf.org/html/rfc7838#section-4)
+// ------------------------------------------------------------
+//
+// The ALTSVC frame (type=0xA) advertises the availability of an alternative service to the client.
+//
+// The ALTSVC frame does not define any flags.
+
+frameTypes[0xA] = 'ALTSVC';
+
+frameFlags.ALTSVC = [];
+
+//     0                   1                   2                   3
+//     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+//    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//    |         Origin-Len (16)       | Origin? (*)                 ...
+//    +-------------------------------+----------------+--------------+
+//    |                   Alt-Svc-Field-Value (*)                   ...
+//    +---------------------------------------------------------------+
+//
+// The ALTSVC frame contains the following fields:
+//
+// Origin-Len: An unsigned, 16-bit integer indicating the length, in
+//    octets, of the Origin field.
+//
+// Origin: An OPTIONAL sequence of characters containing ASCII
+//    serialisation of an origin ([RFC6454](https://tools.ietf.org/html/rfc6454),
+//    Section 6.2) that the alternate service is applicable to.
+//
+// Alt-Svc-Field-Value: A sequence of octets (length determined by
+//    subtracting the length of all preceding fields from the frame
+//    length) containing a value identical to the Alt-Svc field value
+//    defined in (Section 3)[https://tools.ietf.org/html/rfc7838#section-3]
+//    (ABNF production "Alt-Svc").
+
+typeSpecificAttributes.ALTSVC = ['maxAge', 'port', 'protocolID', 'host',
+                                 'origin'];
+
+function istchar(c) {
+  return ('!#$&\'*+-.^_`|~1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.indexOf(c) > -1);
+}
+
+function hexencode(s) {
+  var t = '';
+  for (var i = 0; i < s.length; i++) {
+    if (!istchar(s[i])) {
+      t += '%';
+      t += Buffer.from(s[i]).toString('hex');
+    } else {
+      t += s[i];
+    }
+  }
+  return t;
+}
+
+Serializer.ALTSVC = function writeAltSvc(frame, buffers) {
+  var buffer = Buffer.alloc(2);
+  buffer.writeUInt16BE(frame.origin.length, 0);
+  buffers.push(buffer);
+  buffers.push(Buffer.from(frame.origin, 'ascii'));
+
+  var fieldValue = hexencode(frame.protocolID) + '="' + frame.host + ':' + frame.port + '"';
+  if (frame.maxAge !== 86400) { // 86400 is the default
+    fieldValue += "; ma=" + frame.maxAge;
+  }
+
+  buffers.push(Buffer.from(fieldValue, 'ascii'));
+};
+
+function stripquotes(s) {
+  var start = 0;
+  var end = s.length;
+  while ((start < end) && (s[start] === '"')) {
+    start++;
+  }
+  while ((end > start) && (s[end - 1] === '"')) {
+    end--;
+  }
+  if (start >= end) {
+    return "";
+  }
+  return s.substring(start, end);
+}
+
+function splitNameValue(nvpair) {
+  var eq = -1;
+  var inQuotes = false;
+
+  for (var i = 0; i < nvpair.length; i++) {
+    if (nvpair[i] === '"') {
+      inQuotes = !inQuotes;
+      continue;
+    }
+    if (inQuotes) {
+      continue;
+    }
+    if (nvpair[i] === '=') {
+      eq = i;
+      break;
+    }
+  }
+
+  if (eq === -1) {
+    return {'name': nvpair, 'value': null};
+  }
+
+  var name = stripquotes(nvpair.substring(0, eq).trim());
+  var value = stripquotes(nvpair.substring(eq + 1).trim());
+  return {'name': name, 'value': value};
+}
+
+function splitHeaderParameters(hv) {
+  return parseHeaderValue(hv, ';', splitNameValue);
+}
+
+function parseHeaderValue(hv, separator, callback) {
+  var start = 0;
+  var inQuotes = false;
+  var values = [];
+
+  for (var i = 0; i < hv.length; i++) {
+    if (hv[i] === '"') {
+      inQuotes = !inQuotes;
+      continue;
+    }
+    if (inQuotes) {
+      // Just skip this
+      continue;
+    }
+    if (hv[i] === separator) {
+      var newValue = hv.substring(start, i).trim();
+      if (newValue.length > 0) {
+        newValue = callback(newValue);
+        values.push(newValue);
+      }
+      start = i + 1;
+    }
+  }
+
+  var newValue = hv.substring(start).trim();
+  if (newValue.length > 0) {
+    newValue = callback(newValue);
+    values.push(newValue);
+  }
+
+  return values;
+}
+
+function rsplit(s, delim, count) {
+  var nsplits = 0;
+  var end = s.length;
+  var rval = [];
+  for (var i = s.length - 1; i >= 0; i--) {
+    if (s[i] === delim) {
+      var t = s.substring(i + 1, end);
+      end = i;
+      rval.unshift(t);
+      nsplits++;
+      if (nsplits === count) {
+        break;
+      }
+    }
+  }
+  if (end !== 0) {
+    rval.unshift(s.substring(0, end));
+  }
+  return rval;
+}
+
+function ishex(c) {
+  return ('0123456789ABCDEFabcdef'.indexOf(c) > -1);
+}
+
+function unescape(s) {
+  var i = 0;
+  var t = '';
+  while (i < s.length) {
+    if (s[i] != '%' || !ishex(s[i + 1]) || !ishex(s[i + 2])) {
+      t += s[i];
+    } else {
+      ++i;
+      var hexvalue = '';
+      if (i < s.length) {
+        hexvalue += s[i];
+        ++i;
+      }
+      if (i < s.length) {
+        hexvalue += s[i];
+      }
+      if (hexvalue.length > 0) {
+        t += Buffer.from(hexvalue, 'hex').toString();
+      } else {
+        t += '%';
+      }
+    }
+
+    ++i;
+  }
+  return t;
+}
+
+Deserializer.ALTSVC = function readAltSvc(buffer, frame) {
+  if (buffer.length < 2) {
+    return 'FRAME_SIZE_ERROR';
+  }
+  var originLength = buffer.readUInt16BE(0);
+  if ((buffer.length - 2) < originLength) {
+    return 'FRAME_SIZE_ERROR';
+  }
+  frame.origin = buffer.toString('ascii', 2, 2 + originLength);
+  var fieldValue = buffer.toString('ascii', 2 + originLength);
+  var values = parseHeaderValue(fieldValue, ',', splitHeaderParameters);
+  if (values.length > 1) {
+    // TODO - warn that we only use one here
+  }
+  if (values.length === 0) {
+    // Well that's a malformed frame. Just ignore it.
+    return;
+  }
+
+  var chosenAltSvc = values[0];
+  frame.maxAge = 86400; // Default
+  for (var i = 0; i < chosenAltSvc.length; i++) {
+    if (i === 0) {
+      // This corresponds to the protocolID="<host>:<port>" item
+      frame.protocolID = unescape(chosenAltSvc[i].name);
+      var hostport = rsplit(chosenAltSvc[i].value, ':', 1);
+      frame.host = hostport[0];
+      frame.port = parseInt(hostport[1], 10);
+    } else if (chosenAltSvc[i].name == 'ma') {
+      frame.maxAge = parseInt(chosenAltSvc[i].value, 10);
+    }
+    // Otherwise, we just ignore this
+  }
+};
+
+// frame 0xB was BLOCKED and some versions of chrome will
+// throw PROTOCOL_ERROR upon seeing it with non 0 payload
+
+frameTypes[0xC] = 'ORIGIN';
+frameFlags.ORIGIN = [];
+typeSpecificAttributes.ORIGIN = ['originList'];
+
+Serializer.ORIGIN = function writeOrigin(frame, buffers) {
+  for (var i = 0; i < frame.originList.length; i++) {
+    var buffer = Buffer.alloc(2);
+    buffer.writeUInt16BE(frame.originList[i].length, 0);
+    buffers.push(buffer);
+    buffers.push(Buffer.from(frame.originList[i], 'ascii'));
+  }
+};
+
+Deserializer.ORIGIN = function readOrigin(buffer, frame) {
+    // ignored
+};
+
+
+// [Error Codes](https://tools.ietf.org/html/rfc7540#section-7)
+// ------------------------------------------------------------
+
+var errorCodes = [
+  'NO_ERROR',
+  'PROTOCOL_ERROR',
+  'INTERNAL_ERROR',
+  'FLOW_CONTROL_ERROR',
+  'SETTINGS_TIMEOUT',
+  'STREAM_CLOSED',
+  'FRAME_SIZE_ERROR',
+  'REFUSED_STREAM',
+  'CANCEL',
+  'COMPRESSION_ERROR',
+  'CONNECT_ERROR',
+  'ENHANCE_YOUR_CALM',
+  'INADEQUATE_SECURITY',
+  'HTTP_1_1_REQUIRED'
+];
+
+// Logging
+// -------
+
+// [Bunyan serializers](https://github.com/trentm/node-bunyan#serializers) to improve logging output
+// for debug messages emitted in this component.
+exports.serializers = {};
+
+// * `frame` serializer: it transforms data attributes from Buffers to hex strings and filters out
+//   flags that are not present.
+var frameCounter = 0;
+exports.serializers.frame = function(frame) {
+  if (!frame) {
+    return null;
+  }
+
+  if ('id' in frame) {
+    return frame.id;
+  }
+
+  frame.id = frameCounter;
+  frameCounter += 1;
+
+  var logEntry = { id: frame.id };
+  genericAttributes.concat(typeSpecificAttributes[frame.type]).forEach(function(name) {
+    logEntry[name] = frame[name];
+  });
+
+  if (frame.data instanceof Buffer) {
+    if (logEntry.data.length > 50) {
+      logEntry.data = frame.data.slice(0, 47).toString('hex') + '...';
+    } else {
+      logEntry.data = frame.data.toString('hex');
+    }
+
+    if (!('length' in logEntry)) {
+      logEntry.length = frame.data.length;
+    }
+  }
+
+  if (frame.promised_stream instanceof Object) {
+    logEntry.promised_stream = 'stream-' + frame.promised_stream.id;
+  }
+
+  logEntry.flags = Object.keys(frame.flags || {}).filter(function(name) {
+    return frame.flags[name] === true;
+  });
+
+  return logEntry;
+};
+
+// * `data` serializer: it simply transforms a buffer to a hex string.
+exports.serializers.data = function(data) {
+  return data.toString('hex');
+};