1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
# SPDX-FileCopyrightText: 2024 Greenbone AG
#
# SPDX-License-Identifier: GPL-3.0-or-later
import logging
import socket as socketlib
from abc import ABC, abstractmethod
from time import time
from typing import Optional, Protocol, Union, runtime_checkable
from gvm.errors import GvmError
BUF_SIZE = 16 * 1024
DEFAULT_TIMEOUT = 60 # in seconds
logger = logging.getLogger(__name__)
@runtime_checkable
class GvmConnection(Protocol):
"""
Python `protocol <https://docs.python.org/3/library/typing.html#typing.Protocol>`_
for GvmConnection classes.
"""
def connect(self) -> None:
"""Establish a connection to a remote server"""
def disconnect(self) -> None:
"""Send data to the connected remote server
Arguments:
data: Data to be send to the server. Either utf-8 encoded string or
bytes.
"""
def send(self, data: bytes) -> None:
"""Send data to the connected remote server
Args:
data: Data to be send to the server as bytes.
"""
def read(self) -> bytes:
"""Read data from the remote server
Returns:
data as bytes
"""
def finish_send(self):
"""Indicate to the remote server you are done with sending data"""
class AbstractGvmConnection(ABC):
"""
Base class for establishing a connection to a remote server daemon.
Arguments:
timeout: Timeout in seconds for the connection. None to
wait indefinitely
"""
def __init__(self, timeout: Optional[Union[int, float]] = DEFAULT_TIMEOUT):
self._socket: Optional[socketlib.SocketType] = None
self._timeout = timeout if timeout is not None else DEFAULT_TIMEOUT
def _read(self) -> bytes:
if self._socket is None:
raise GvmError("Socket is not connected")
return self._socket.recv(BUF_SIZE)
@abstractmethod
def connect(self) -> None:
"""Establish a connection to a remote server"""
raise NotImplementedError
def send(self, data: bytes) -> None:
"""Send data to the connected remote server
Args:
data: Data to be send to the server as bytes.
"""
if self._socket is None:
raise GvmError("Socket is not connected")
self._socket.sendall(data)
def read(self) -> bytes:
"""Read data from the remote server
Returns:
data as bytes
"""
break_timeout = (
time() + self._timeout if self._timeout is not None else None
)
data = self._read()
if not data:
# Connection was closed by server
raise GvmError("Remote closed the connection")
if break_timeout and time() > break_timeout:
raise GvmError("Timeout while reading the response")
return data
def disconnect(self) -> None:
"""Disconnect and close the connection to the remote server"""
try:
if self._socket is not None:
self._socket.close()
except OSError as e:
logger.debug("Connection closing error: %s", e)
def finish_send(self):
"""Indicate to the remote server you are done with sending data"""
if self._socket is not None:
# shutdown socket for sending. only allow reading data afterwards
self._socket.shutdown(socketlib.SHUT_WR)
|
