fix: 修复代理问题

.venv/lib/python3.9/site-packages/python_socks/_protocols/socks4.py

@@ -0,0 +1,116 @@
+import enum
+import ipaddress
+import socket
+from dataclasses import dataclass
+from typing import Optional
+
+from .errors import ReplyError
+from .._helpers import is_ipv4_address
+
+RSV = NULL = 0x00
+SOCKS_VER = 0x04
+
+
+class Command(enum.IntEnum):
+    CONNECT = 0x01
+    BIND = 0x02
+
+
+class ReplyCode(enum.IntEnum):
+    REQUEST_GRANTED = 0x5A
+    REQUEST_REJECTED_OR_FAILED = 0x5B
+    CONNECTION_FAILED = 0x5C
+    AUTHENTICATION_FAILED = 0x5D
+
+
+ReplyMessages = {
+    ReplyCode.REQUEST_GRANTED: 'Request granted',
+    ReplyCode.REQUEST_REJECTED_OR_FAILED: 'Request rejected or failed',
+    ReplyCode.CONNECTION_FAILED: (
+        'Request rejected because SOCKS server cannot connect to identd on the client'
+    ),
+    ReplyCode.AUTHENTICATION_FAILED: (
+        'Request rejected because the client program and identd report different user-ids'
+    ),
+}
+
+
+@dataclass
+class ConnectRequest:
+    host: str  # hostname or IPv4 address
+    port: int
+    user_id: Optional[str]
+
+    def dumps(self):
+        port_bytes = self.port.to_bytes(2, 'big')
+        include_hostname = False
+
+        if is_ipv4_address(self.host):
+            host_bytes = ipaddress.IPv4Address(self.host).packed
+        else:
+            include_hostname = True
+            host_bytes = bytes([NULL, NULL, NULL, 1])
+
+        data = bytearray([SOCKS_VER, Command.CONNECT])
+        data += port_bytes
+        data += host_bytes
+
+        if self.user_id:
+            data += self.user_id.encode('ascii')
+
+        data.append(NULL)
+
+        if include_hostname:
+            data += self.host.encode('idna')
+            data.append(NULL)
+
+        return bytes(data)
+
+
+@dataclass
+class ConnectReply:
+    SIZE = 8
+
+    rsv: int
+    reply: ReplyCode
+    host: str  # should be ignored when using Command.CONNECT
+    port: int  # should be ignored when using Command.CONNECT
+
+    @classmethod
+    def loads(cls, data: bytes) -> 'ConnectReply':
+        if len(data) != cls.SIZE:
+            raise ReplyError('Malformed connect reply')
+
+        rsv = data[0]
+        if rsv != RSV:  # pragma: no cover
+            raise ReplyError(f'Unexpected reply version: {data[0]:#02X}')
+
+        try:
+            reply = ReplyCode(data[1])
+        except ValueError:
+            raise ReplyError(f'Invalid reply code: {data[1]:#02X}')
+
+        if reply != ReplyCode.REQUEST_GRANTED:  # pragma: no cover
+            msg = ReplyMessages.get(reply, 'Unknown error')
+            raise ReplyError(msg, error_code=reply)
+
+        try:
+            port = int.from_bytes(data[2:4], byteorder="big")
+        except ValueError:
+            raise ReplyError('Invalid port data')
+
+        try:
+            host = socket.inet_ntop(socket.AF_INET, data[4:8])
+        except ValueError:
+            raise ReplyError('Invalid port data')
+
+        return cls(rsv=rsv, reply=reply, host=host, port=port)
+
+
+# noinspection PyMethodMayBeStatic
+class Connection:
+    def send(self, request: ConnectRequest) -> bytes:
+        return request.dumps()
+
+    def receive(self, data: bytes) -> ConnectReply:
+        return ConnectReply.loads(data)