diff options
Diffstat (limited to 'netlib/websockets')
| -rw-r--r-- | netlib/websockets/__init__.py | 2 | ||||
| -rw-r--r-- | netlib/websockets/frame.py | 316 | ||||
| -rw-r--r-- | netlib/websockets/protocol.py | 115 |
3 files changed, 0 insertions, 433 deletions
diff --git a/netlib/websockets/__init__.py b/netlib/websockets/__init__.py deleted file mode 100644 index 1c143919..00000000 --- a/netlib/websockets/__init__.py +++ /dev/null @@ -1,2 +0,0 @@ -from .frame import * -from .protocol import * diff --git a/netlib/websockets/frame.py b/netlib/websockets/frame.py deleted file mode 100644 index fce2c9d3..00000000 --- a/netlib/websockets/frame.py +++ /dev/null @@ -1,316 +0,0 @@ -from __future__ import absolute_import -import os -import struct -import io -import warnings - -import six - -from .protocol import Masker -from netlib import tcp -from netlib import utils - - -MAX_16_BIT_INT = (1 << 16) -MAX_64_BIT_INT = (1 << 64) - -DEFAULT=object() - -OPCODE = utils.BiDi( - CONTINUE=0x00, - TEXT=0x01, - BINARY=0x02, - CLOSE=0x08, - PING=0x09, - PONG=0x0a -) - - -class FrameHeader(object): - - def __init__( - self, - opcode=OPCODE.TEXT, - payload_length=0, - fin=False, - rsv1=False, - rsv2=False, - rsv3=False, - masking_key=DEFAULT, - mask=DEFAULT, - length_code=DEFAULT - ): - if not 0 <= opcode < 2 ** 4: - raise ValueError("opcode must be 0-16") - self.opcode = opcode - self.payload_length = payload_length - self.fin = fin - self.rsv1 = rsv1 - self.rsv2 = rsv2 - self.rsv3 = rsv3 - - if length_code is DEFAULT: - self.length_code = self._make_length_code(self.payload_length) - else: - self.length_code = length_code - - if mask is DEFAULT and masking_key is DEFAULT: - self.mask = False - self.masking_key = b"" - elif mask is DEFAULT: - self.mask = 1 - self.masking_key = masking_key - elif masking_key is DEFAULT: - self.mask = mask - self.masking_key = os.urandom(4) - else: - self.mask = mask - self.masking_key = masking_key - - if self.masking_key and len(self.masking_key) != 4: - raise ValueError("Masking key must be 4 bytes.") - - @classmethod - def _make_length_code(self, length): - """ - A websockets frame contains an initial length_code, and an optional - extended length code to represent the actual length if length code is - larger than 125 - """ - if length <= 125: - return length - elif length >= 126 and length <= 65535: - return 126 - else: - return 127 - - def __repr__(self): - vals = [ - "ws frame:", - OPCODE.get_name(self.opcode, hex(self.opcode)).lower() - ] - flags = [] - for i in ["fin", "rsv1", "rsv2", "rsv3", "mask"]: - if getattr(self, i): - flags.append(i) - if flags: - vals.extend([":", "|".join(flags)]) - if self.masking_key: - vals.append(":key=%s" % repr(self.masking_key)) - if self.payload_length: - vals.append(" %s" % utils.pretty_size(self.payload_length)) - return "".join(vals) - - def human_readable(self): - warnings.warn("FrameHeader.to_bytes is deprecated, use bytes(frame_header) instead.", DeprecationWarning) - return repr(self) - - def __bytes__(self): - first_byte = utils.setbit(0, 7, self.fin) - first_byte = utils.setbit(first_byte, 6, self.rsv1) - first_byte = utils.setbit(first_byte, 5, self.rsv2) - first_byte = utils.setbit(first_byte, 4, self.rsv3) - first_byte = first_byte | self.opcode - - second_byte = utils.setbit(self.length_code, 7, self.mask) - - b = six.int2byte(first_byte) + six.int2byte(second_byte) - - if self.payload_length < 126: - pass - elif self.payload_length < MAX_16_BIT_INT: - # '!H' pack as 16 bit unsigned short - # add 2 byte extended payload length - b += struct.pack('!H', self.payload_length) - elif self.payload_length < MAX_64_BIT_INT: - # '!Q' = pack as 64 bit unsigned long long - # add 8 bytes extended payload length - b += struct.pack('!Q', self.payload_length) - if self.masking_key: - b += self.masking_key - return b - - if six.PY2: - __str__ = __bytes__ - - def to_bytes(self): - warnings.warn("FrameHeader.to_bytes is deprecated, use bytes(frame_header) instead.", DeprecationWarning) - return bytes(self) - - @classmethod - def from_file(cls, fp): - """ - read a websockets frame header - """ - first_byte = six.byte2int(fp.safe_read(1)) - second_byte = six.byte2int(fp.safe_read(1)) - - fin = utils.getbit(first_byte, 7) - rsv1 = utils.getbit(first_byte, 6) - rsv2 = utils.getbit(first_byte, 5) - rsv3 = utils.getbit(first_byte, 4) - # grab right-most 4 bits - opcode = first_byte & 15 - mask_bit = utils.getbit(second_byte, 7) - # grab the next 7 bits - length_code = second_byte & 127 - - # payload_lengthy > 125 indicates you need to read more bytes - # to get the actual payload length - if length_code <= 125: - payload_length = length_code - elif length_code == 126: - payload_length, = struct.unpack("!H", fp.safe_read(2)) - elif length_code == 127: - payload_length, = struct.unpack("!Q", fp.safe_read(8)) - - # masking key only present if mask bit set - if mask_bit == 1: - masking_key = fp.safe_read(4) - else: - masking_key = None - - return cls( - fin=fin, - rsv1=rsv1, - rsv2=rsv2, - rsv3=rsv3, - opcode=opcode, - mask=mask_bit, - length_code=length_code, - payload_length=payload_length, - masking_key=masking_key, - ) - - def __eq__(self, other): - if isinstance(other, FrameHeader): - return bytes(self) == bytes(other) - return False - - -class Frame(object): - - """ - Represents one websockets frame. - Constructor takes human readable forms of the frame components - from_bytes() is also avaliable. - - WebSockets Frame as defined in RFC6455 - - 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 - +-+-+-+-+-------+-+-------------+-------------------------------+ - |F|R|R|R| opcode|M| Payload len | Extended payload length | - |I|S|S|S| (4) |A| (7) | (16/64) | - |N|V|V|V| |S| | (if payload len==126/127) | - | |1|2|3| |K| | | - +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - + - | Extended payload length continued, if payload len == 127 | - + - - - - - - - - - - - - - - - +-------------------------------+ - | |Masking-key, if MASK set to 1 | - +-------------------------------+-------------------------------+ - | Masking-key (continued) | Payload Data | - +-------------------------------- - - - - - - - - - - - - - - - + - : Payload Data continued ... : - + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + - | Payload Data continued ... | - +---------------------------------------------------------------+ - """ - - def __init__(self, payload=b"", **kwargs): - self.payload = payload - kwargs["payload_length"] = kwargs.get("payload_length", len(payload)) - self.header = FrameHeader(**kwargs) - - @classmethod - def default(cls, message, from_client=False): - """ - Construct a basic websocket frame from some default values. - Creates a non-fragmented text frame. - """ - if from_client: - mask_bit = 1 - masking_key = os.urandom(4) - else: - mask_bit = 0 - masking_key = None - - return cls( - message, - fin=1, # final frame - opcode=OPCODE.TEXT, # text - mask=mask_bit, - masking_key=masking_key, - ) - - @classmethod - def from_bytes(cls, bytestring): - """ - Construct a websocket frame from an in-memory bytestring - to construct a frame from a stream of bytes, use from_file() directly - """ - return cls.from_file(tcp.Reader(io.BytesIO(bytestring))) - - def __repr__(self): - ret = repr(self.header) - if self.payload: - ret = ret + "\nPayload:\n" + utils.clean_bin(self.payload).decode("ascii") - return ret - - def human_readable(self): - warnings.warn("Frame.to_bytes is deprecated, use bytes(frame) instead.", DeprecationWarning) - return repr(self) - - def __bytes__(self): - """ - Serialize the frame to wire format. Returns a string. - """ - b = bytes(self.header) - if self.header.masking_key: - b += Masker(self.header.masking_key)(self.payload) - else: - b += self.payload - return b - - if six.PY2: - __str__ = __bytes__ - - def to_bytes(self): - warnings.warn("FrameHeader.to_bytes is deprecated, use bytes(frame_header) instead.", DeprecationWarning) - return bytes(self) - - def to_file(self, writer): - warnings.warn("Frame.to_file is deprecated, use wfile.write(bytes(frame)) instead.", DeprecationWarning) - writer.write(bytes(self)) - writer.flush() - - @classmethod - def from_file(cls, fp): - """ - read a websockets frame sent by a server or client - - fp is a "file like" object that could be backed by a network - stream or a disk or an in memory stream reader - """ - header = FrameHeader.from_file(fp) - payload = fp.safe_read(header.payload_length) - - if header.mask == 1 and header.masking_key: - payload = Masker(header.masking_key)(payload) - - return cls( - payload, - fin=header.fin, - opcode=header.opcode, - mask=header.mask, - payload_length=header.payload_length, - masking_key=header.masking_key, - rsv1=header.rsv1, - rsv2=header.rsv2, - rsv3=header.rsv3, - length_code=header.length_code - ) - - def __eq__(self, other): - if isinstance(other, Frame): - return bytes(self) == bytes(other) - return False diff --git a/netlib/websockets/protocol.py b/netlib/websockets/protocol.py deleted file mode 100644 index 1e95fa1c..00000000 --- a/netlib/websockets/protocol.py +++ /dev/null @@ -1,115 +0,0 @@ - - - -# Colleciton of utility functions that implement small portions of the RFC6455 -# WebSockets Protocol Useful for building WebSocket clients and servers. -# -# Emphassis is on readabilty, simplicity and modularity, not performance or -# completeness -# -# This is a work in progress and does not yet contain all the utilites need to -# create fully complient client/servers # -# Spec: https://tools.ietf.org/html/rfc6455 - -# The magic sha that websocket servers must know to prove they understand -# RFC6455 -from __future__ import absolute_import -import base64 -import hashlib -import os - -import binascii -import six -from ..http import Headers - -websockets_magic = b'258EAFA5-E914-47DA-95CA-C5AB0DC85B11' -VERSION = "13" - - -class Masker(object): - - """ - Data sent from the server must be masked to prevent malicious clients - from sending data over the wire in predictable patterns - - Servers do not have to mask data they send to the client. - https://tools.ietf.org/html/rfc6455#section-5.3 - """ - - def __init__(self, key): - self.key = key - self.offset = 0 - - def mask(self, offset, data): - result = bytearray(data) - if six.PY2: - for i in range(len(data)): - result[i] ^= ord(self.key[offset % 4]) - offset += 1 - result = str(result) - else: - - for i in range(len(data)): - result[i] ^= self.key[offset % 4] - offset += 1 - result = bytes(result) - return result - - def __call__(self, data): - ret = self.mask(self.offset, data) - self.offset += len(ret) - return ret - - -class WebsocketsProtocol(object): - - def __init__(self): - pass - - @classmethod - def client_handshake_headers(self, key=None, version=VERSION): - """ - Create the headers for a valid HTTP upgrade request. If Key is not - specified, it is generated, and can be found in sec-websocket-key in - the returned header set. - - Returns an instance of Headers - """ - if not key: - key = base64.b64encode(os.urandom(16)).decode('ascii') - return Headers( - sec_websocket_key=key, - sec_websocket_version=version, - connection="Upgrade", - upgrade="websocket", - ) - - @classmethod - def server_handshake_headers(self, key): - """ - The server response is a valid HTTP 101 response. - """ - return Headers( - sec_websocket_accept=self.create_server_nonce(key), - connection="Upgrade", - upgrade="websocket" - ) - - - @classmethod - def check_client_handshake(self, headers): - if headers.get("upgrade") != "websocket": - return - return headers.get("sec-websocket-key") - - - @classmethod - def check_server_handshake(self, headers): - if headers.get("upgrade") != "websocket": - return - return headers.get("sec-websocket-accept") - - - @classmethod - def create_server_nonce(self, client_nonce): - return base64.b64encode(hashlib.sha1(client_nonce + websockets_magic).digest()) |