pypush-plus-plus/apns.py
2023-05-02 17:48:47 -04:00

233 lines
6.6 KiB
Python

from __future__ import annotations
import random
import socket
import threading
import time
from hashlib import sha1
import tlslite
import albert
COURIER_HOST = "windows.courier.push.apple.com" # TODO: Get this from config
COURIER_PORT = 5223
ALPN = [b"apns-security-v2"]
# Connect to the courier server
def _connect(private_key: str, cert: str) -> tlslite.TLSConnection:
# Connect to the courier server
sock = socket.create_connection((COURIER_HOST, COURIER_PORT))
# Wrap the socket in TLS
sock = tlslite.TLSConnection(sock)
# Parse the certificate and private key
cert = tlslite.X509CertChain([tlslite.X509().parse(cert)])
private_key = tlslite.parsePEMKey(private_key, private=True)
# Handshake with the server
sock.handshakeClientCert(cert, private_key, alpn=ALPN)
return sock
class APNSConnection:
incoming_queue = []
def _queue_filler(self):
while True and not self.sock.closed:
# print(self.sock.closed)
# print("QUEUE: Waiting for payload...")
# self.sock.read(1)
# print("QUEUE: Got payload?")
payload = _deserialize_payload(self.sock)
# print("QUEUE: Got payload?")
if payload is not None:
# print("QUEUE: Received payload: " + str(payload))
self.incoming_queue.append(payload)
# print("QUEUE: Thread ended")
def _pop_by_id(self, id: int) -> tuple[int, list[tuple[int, bytes]]] | None:
# print("QUEUE: Looking for id " + str(id) + " in " + str(self.incoming_queue))
for i in range(len(self.incoming_queue)):
if self.incoming_queue[i][0] == id:
return self.incoming_queue.pop(i)
return None
def wait_for_packet(self, id: int) -> tuple[int, list[tuple[int, bytes]]]:
payload = self._pop_by_id(id)
while payload is None:
payload = self._pop_by_id(id)
time.sleep(0.1)
return payload
def __init__(self, private_key=None, cert=None):
# Generate the private key and certificate if they're not provided
if private_key is None or cert is None:
self.private_key, self.cert = albert.generate_push_cert()
else:
self.private_key, self.cert = private_key, cert
self.sock = _connect(self.private_key, self.cert)
# Start the queue filler thread
self.queue_filler_thread = threading.Thread(
target=self._queue_filler, daemon=True
)
self.queue_filler_thread.start()
def connect(self, root: bool = True, token: bytes = None):
flags = 0b01000001
if root:
flags |= 0b0100
if token is None:
payload = _serialize_payload(
7, [(2, 0x01.to_bytes(1, 'big')), (5, flags.to_bytes(4, 'big'))]
)
else:
payload = _serialize_payload(
7, [(1, token), (2, 0x01.to_bytes(1, 'big')), (5, flags.to_bytes(4, 'big'))]
)
self.sock.write(payload)
payload = self.wait_for_packet(8)
if (
payload == None
or payload[0] != 8
or _get_field(payload[1], 1) != 0x00.to_bytes(1, 'big')
):
raise Exception("Failed to connect")
new_token = _get_field(payload[1], 3)
if new_token is not None:
self.token = new_token
elif token is not None:
self.token = token
else:
raise Exception("No token")
return self.token
def filter(self, topics: list[str]):
fields = [(1, self.token)]
for topic in topics:
fields.append((2, sha1(topic.encode()).digest()))
payload = _serialize_payload(9, fields)
self.sock.write(payload)
def send_message(self, topic: str, payload: str, id=None):
if id is None:
id = random.randbytes(4)
payload = _serialize_payload(
0x0A,
[
(4, id),
(1, sha1(topic.encode()).digest()),
(2, self.token),
(3, payload),
],
)
self.sock.write(payload)
payload = self.wait_for_packet(0x0B)
if payload[1][0][1] != 0x00.to_bytes(1, 'big'):
raise Exception("Failed to send message")
def set_state(self, state: int):
self.sock.write(
_serialize_payload(
0x14, [(1, state.to_bytes(1, 'big')), (2, 0x7FFFFFFF.to_bytes(4, 'big'))]
)
)
def keep_alive(self):
self.sock.write(_serialize_payload(0x0C, []))
# TODO: Find a way to make this non-blocking
# def expect_message(self) -> tuple[int, list[tuple[int, bytes]]] | None:
# return _deserialize_payload(self.sock)
def _serialize_field(id: int, value: bytes) -> bytes:
return id.to_bytes(1, 'big') + len(value).to_bytes(2, "big") + value
def _serialize_payload(id: int, fields: list[(int, bytes)]) -> bytes:
payload = b""
for fid, value in fields:
if fid is not None:
payload += _serialize_field(fid, value)
return id.to_bytes(1, 'big') + len(payload).to_bytes(4, "big") + payload
def _deserialize_field(stream: bytes) -> tuple[int, bytes]:
id = int.from_bytes(stream[:1], "big")
length = int.from_bytes(stream[1:3], "big")
value = stream[3 : 3 + length]
return id, value
# Note: Takes a stream, not a buffer, as we do not know the length of the payload
# WILL BLOCK IF THE STREAM IS EMPTY
def _deserialize_payload(stream) -> tuple[int, list[tuple[int, bytes]]] | None:
id = int.from_bytes(stream.read(1), "big")
if id == 0x0:
return None
length = int.from_bytes(stream.read(4), "big")
buffer = stream.read(length)
fields = []
while len(buffer) > 0:
fid, value = _deserialize_field(buffer)
fields.append((fid, value))
buffer = buffer[3 + len(value) :]
return id, fields
def _deserialize_payload_from_buffer(
buffer: bytes,
) -> tuple[int, list[tuple[int, bytes]]] | None:
id = int.from_bytes(buffer[:1], "big")
if id == 0x0:
return None
length = int.from_bytes(buffer[1:5], "big")
buffer = buffer[5:]
if len(buffer) < length:
raise Exception("Buffer is too short")
fields = []
while len(buffer) > 0:
fid, value = _deserialize_field(buffer)
fields.append((fid, value))
buffer = buffer[3 + len(value) :]
return id, fields
# Returns the value of the first field with the given id
def _get_field(fields: list[tuple[int, bytes]], id: int) -> bytes:
for field_id, value in fields:
if field_id == id:
return value
return None