Python FTP隐式TLS连接问题
- 2025-03-21 09:06:00
- admin 原创
- 33
问题描述:
我需要连接到 FTPS 服务器,我可以使用 lftp 成功连接到该服务器。但是,当我尝试使用 Python ftplib.FTP_TLS 时,它超时了,堆栈跟踪显示它正在等待服务器发送欢迎消息或类似消息。有人知道问题是什么以及如何克服吗?我想知道服务器端是否需要做些什么,但是为什么 lftp 客户端工作正常。任何帮助都非常感谢。
以下是堆栈跟踪:
ftp = ftplib.FTP_TLS()
ftp.connect(cfg.HOST, cfg.PORT, timeout=60)
File "C:Users/usernameSoftwaresPython27libtplib.py", line 135, in connect
self.welcome = self.getresp()
File "C:Users/usernameSoftwaresPython27libtplib.py", line 210, in getresp
resp = self.getmultiline()
File "C:Users/usernameSoftwaresPython27libtplib.py", line 196, in getmultiline
line = self.getline()
File "C:Users/usernameSoftwaresPython27libtplib.py", line 183, in getline
line = self.file.readline()
File "C:Users/usernameSoftwaresPython27libsocket.py", line 447, in readline
data = self._sock.recv(self._rbufsize)
socket.timeout: timed out
使用 lftp 成功登录到同一个 ftps 服务器:
$ lftp
lftp :~> open ftps://ip_address:990
lftp ip_address:~> set ftps:initial-prot P
lftp ip_address:~> login ftps_user_id ftps_user_passwd
lftp sftp_user_id@ip_address:~> ls
ls: Fatal error: SSL_connect: self signed certificate
lftp ftps_user_id@ip_address:~> set ssl:verif-certificate off
lftp ftps_user_id@ip_address:~> ls
lftp ftps_user_id@ip_address:/>
顺便说一句,我使用的是 Python 2.7.3。我使用 Google 进行了大量搜索,但没有找到任何有用的信息。
我仍然遇到这个问题,如果有人能帮助我将不胜感激。仔细查看 FTP.connect() 后发现,与服务器的连接没有问题,但从服务器获取确认(或欢迎消息)是一个问题。lftp 没有这个问题,FileZilla 也没有任何问题,如这里的日志所示 -
Status: Connecting to xx.xx.xx.xxx:990...
Status: Connection established, initializing TLS...
Status: Verifying certificate...
Status: TLS/SSL connection established, waiting for welcome message...
Response: 220- Vous allez vous connecter sur un serveur prive
Response: 220- Seules les personnes habilitees y sont autorisees
Response: 220 Les contrevenants s'exposent aux poursuites prevues par la loi.
Command: USER xxxxxxxxxxxxx
Response: 331 Password required for xxxxxxxxxxxxx.
Command: PASS **********
Response: 230 Login OK. Proceed.
Command: PBSZ 0
Response: 200 PBSZ Command OK. Protection buffer size set to 0.
Command: PROT P
Response: 200 PROT Command OK. Using Private data connection
Status: Connected
Status: Retrieving directory listing...
Command: PWD
Response: 257 "/" is current folder.
Command: TYPE I
Response: 200 Type set to I.
Command: PASV
Response: 227 Entering Passive Mode (81,93,20,199,4,206).
Command: MLSD
Response: 150 Opening BINARY mode data connection for MLSD /.
Response: 226 Transfer complete. 0 bytes transferred. 0 bps.
Status: Directory listing successful
解决方案 1:
扩展迄今为止提出的解决方案,问题是隐式 FTPS 连接需要自动对套接字进行 ssl 包装,然后我们才有机会调用 login()。人们提出的许多子类都是在 connect 方法的上下文中执行此操作的,我们可以更普遍地通过修改 self.sock 的 get/set 来管理此操作,并在设置时使用自动包装的属性:
import ftplib
import ssl
class ImplicitFTP_TLS(ftplib.FTP_TLS):
"""FTP_TLS subclass that automatically wraps sockets in SSL to support implicit FTPS."""
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self._sock = None
@property
def sock(self):
"""Return the socket."""
return self._sock
@sock.setter
def sock(self, value):
"""When modifying the socket, ensure that it is ssl wrapped."""
if value is not None and not isinstance(value, ssl.SSLSocket):
value = self.context.wrap_socket(value)
self._sock = value
使用方法基本与标准 FTP_TLS 类相同:
ftp_client = ImplicitFTP_TLS()
ftp_client.connect(host='ftp.example.com', port=990)
ftp_client.login(user='USERNAME', passwd='PASSWORD')
ftp_client.prot_p()
解决方案 2:
我为同样的问题研究了半天,终于弄明白了。
对于隐式 FTP TLS/SSL(默认端口 990),我们的客户端程序必须在创建套接字后立即建立 TLS/SSL 连接。但是 python 的类FTP_TLS
不会从 FTP 类重新加载connect函数。我们需要修复它:
class tyFTP(ftplib.FTP_TLS):
def __init__(self,
host='',
user='',
passwd='',
acct='',
keyfile=None,
certfile=None,
timeout=60):
ftplib.FTP_TLS.__init__(self,
host=host,
user=user,
passwd=passwd,
acct=acct,
keyfile=keyfile,
certfile=certfile,
timeout=timeout)
def connect(self, host='', port=0, timeout=-999):
"""Connect to host. Arguments are:
- host: hostname to connect to (string, default previous host)
- port: port to connect to (integer, default previous port)
"""
if host != '':
self.host = host
if port > 0:
self.port = port
if timeout != -999:
self.timeout = timeout
try:
self.sock = socket.create_connection((self.host, self.port), self.timeout)
self.af = self.sock.family
# add this line!!!
self.sock = ssl.wrap_socket(self.sock,
self.keyfile,
self.certfile,
ssl_version=ssl.PROTOCOL_TLSv1)
# add end
self.file = self.sock.makefile('rb')
self.welcome = self.getresp()
except Exception as e:
print(e)
return self.welcome
此派生类重新加载了connectFTP_TLS.prot_p()
函数并围绕套接字构建了 TLS 包装器。成功连接并登录 FTP 服务器后,您需要在执行任何 FTP 命令之前调用:!
希望这会有所帮助^_^
解决方案 3:
这是一个更加“工业化”的实现。
我们注意到,在前面的例子中, init中缺少名为“context”的属性。
下面的代码在 Python 2.7 和 Python 3 中都能完美运行。
代码
import ftplib, socket, ssl
FTPTLS_OBJ = ftplib.FTP_TLS
# Class to manage implicit FTP over TLS connections, with passive transfer mode
# - Important note:
# If you connect to a VSFTPD server, check that the vsftpd.conf file contains
# the property require_ssl_reuse=NO
class FTPTLS(FTPTLS_OBJ):
host = "127.0.0.1"
port = 990
user = "anonymous"
timeout = 60
logLevel = 0
# Init both this and super
def __init__(self, host=None, user=None, passwd=None, acct=None, keyfile=None, certfile=None, context=None, timeout=60):
FTPTLS_OBJ.__init__(self, host, user, passwd, acct, keyfile, certfile, context, timeout)
# Custom function: Open a new FTPS session (both connection & login)
def openSession(self, host="127.0.0.1", port=990, user="anonymous", password=None, timeout=60):
self.user = user
# connect()
ret = self.connect(host, port, timeout)
# prot_p(): Set up secure data connection.
try:
ret = self.prot_p()
if (self.logLevel > 1): self._log("INFO - FTPS prot_p() done: " + ret)
except Exception as e:
if (self.logLevel > 0): self._log("ERROR - FTPS prot_p() failed - " + str(e))
raise e
# login()
try:
ret = self.login(user=user, passwd=password)
if (self.logLevel > 1): self._log("INFO - FTPS login() done: " + ret)
except Exception as e:
if (self.logLevel > 0): self._log("ERROR - FTPS login() failed - " + str(e))
raise e
if (self.logLevel > 1): self._log("INFO - FTPS session successfully opened")
# Override function
def connect(self, host="127.0.0.1", port=990, timeout=60):
self.host = host
self.port = port
self.timeout = timeout
try:
self.sock = socket.create_connection((self.host, self.port), self.timeout)
self.af = self.sock.family
self.sock = ssl.wrap_socket(self.sock, self.keyfile, self.certfile)
self.file = self.sock.makefile('r')
self.welcome = self.getresp()
if (self.logLevel > 1): self._log("INFO - FTPS connect() done: " + self.welcome)
except Exception as e:
if (self.logLevel > 0): self._log("ERROR - FTPS connect() failed - " + str(e))
raise e
return self.welcome
# Override function
def makepasv(self):
host, port = FTPTLS_OBJ.makepasv(self)
# Change the host back to the original IP that was used for the connection
host = socket.gethostbyname(self.host)
return host, port
# Custom function: Close the session
def closeSession(self):
try:
self.close()
if (self.logLevel > 1): self._log("INFO - FTPS close() done")
except Exception as e:
if (self.logLevel > 0): self._log("ERROR - FTPS close() failed - " + str(e))
raise e
if (self.logLevel > 1): self._log("INFO - FTPS session successfully closed")
# Private method for logs
def _log(self, msg):
# Be free here on how to implement your own way to redirect logs (e.g: to a console, to a file, etc.)
print(msg)
使用示例
host = "www.myserver.com"
port = 990
user = "myUserId"
password = "myPassword"
myFtps = FTPTLS()
myFtps.logLevel = 2
myFtps.openSession(host, port, user, password)
print(myFtps.retrlines("LIST"))
myFtps.closeSession()
输出示例
INFO - FTPS connect() done: 220 (vsFTPd 3.0.2)
INFO - FTPS prot_p() done: 200 PROT now Private.
INFO - FTPS login() done: 230 Login successful.
INFO - FTPS session successfully opened
-rw------- 1 ftp ftp 86735 Mar 22 16:55 MyModel.yaml
-rw------- 1 ftp ftp 9298 Mar 22 16:55 MyData.csv
226 Directory send OK.
INFO - FTPS close() done
INFO - FTPS session successfully closed
解决方案 4:
扩展 NERV 的回应 - 它对我帮助很大,下面是我如何解决端口 990 上的隐式 TLS 连接需要身份验证的问题。
文件名:ImplicitTLS.py
from ftplib import FTP_TLS
import socket
import ssl
class tyFTP(FTP_TLS):
def __init__(self, host='', user='', passwd='', acct='', keyfile=None, certfile=None, timeout=60):
FTP_TLS.__init__(self, host, user, passwd, acct, keyfile, certfile, timeout)
def connect(self, host='', port=0, timeout=-999):
if host != '':
self.host = host
if port > 0:
self.port = port
if timeout != -999:
self.timeout = timeout
try:
self.sock = socket.create_connection((self.host, self.port), self.timeout)
self.af = self.sock.family
self.sock = ssl.wrap_socket(self.sock, self.keyfile, self.certfile, ssl_version=ssl.PROTOCOL_TLSv1)
self.file = self.sock.makefile('rb')
self.welcome = self.getresp()
except Exception as e:
print e
return self.welcome
然后从我的主应用程序中执行以下操作:
from ImplicityTLS import tyFTP
server = tyFTP()
server.connect(host="xxxxx", port=990)
server.login(user="yyyy", passwd="fffff")
server.prot_p()
就是这样,我可以下载文件等等。感谢 NERV 提供原始答案。
解决方案 5:
NERV 的回答和 Brad Decker 的样本确实很有帮助。非常感谢他们。他们为我节省了好几个小时。
不幸的是,最初它对我来说并不起作用。
ssl_version
就我的情况而言,一旦我从方法中删除了参数,连接就会正常工作ssl.wrap_socket
。此外,要向服务器发送任何命令,我必须ntransfercmd
从FTP_TLS
类中覆盖方法并在那里删除ssl_version
参数。
这就是对我有用的代码:
from ftplib import FTP_TLS, FTP
import socket
import ssl
class IMPLICIT_FTP_TLS(FTP_TLS):
def __init__(self, host='', user='', passwd='', acct='', keyfile=None,
certfile=None, timeout=60):
FTP_TLS.__init__(self, host, user, passwd, acct, keyfile, certfile, timeout)
def connect(self, host='', port=0, timeout=-999):
'''Connect to host. Arguments are:
- host: hostname to connect to (string, default previous host)
- port: port to connect to (integer, default previous port)
'''
if host != '':
self.host = host
if port > 0:
self.port = port
if timeout != -999:
self.timeout = timeout
try:
self.sock = socket.create_connection((self.host, self.port), self.timeout)
self.af = self.sock.family
self.sock = ssl.wrap_socket(self.sock, self.keyfile, self.certfile)
self.file = self.sock.makefile('rb')
self.welcome = self.getresp()
except Exception as e:
print (e)
return self.welcome
def ntransfercmd(self, cmd, rest=None):
conn, size = FTP.ntransfercmd(self, cmd, rest)
if self._prot_p:
conn = ssl.wrap_socket(conn, self.keyfile, self.certfile)
return conn, size
以下是必填示例:
>>> ftps = IMPLICIT_FTP_TLS()
>>> ftps.connect(host='your.ftp.host', port=990)
>>> ftps.login(user="your_user", passwd="your_passwd")
>>> ftps.prot_p()
>>> ftps.retrlines('LIST')
解决方案 6:
我在使用隐式 TLS(也是被动模式)的 FTP 服务器中也遇到了同样的问题。我遇到了多个错误:
450 TLS session of data connection has not resumed or the session does not match the control connection
以及建议的解决方案。根据@George Leslie-Waksman 的记录,我的解决方案是:
class ImplicitFTP_TLS(ftplib.FTP_TLS):
"""
FTP_TLS subclass that automatically wraps sockets in SSL to support implicit FTPS.
Prefer explicit TLS whenever possible.
"""
def __init__(self, *args, **kwargs):
"""Initialise self."""
super().__init__(*args, **kwargs)
self._sock = None
@property
def sock(self):
"""Return the socket."""
return self._sock
@sock.setter
def sock(self, value):
"""When modifying the socket, ensure that it is SSL wrapped."""
if value is not None and not isinstance(value, ssl.SSLSocket):
value = self.context.wrap_socket(value)
self._sock = value
def ntransfercmd(self, cmd, rest=None):
"""Override the ntransfercmd method"""
conn, size = ftplib.FTP.ntransfercmd(self, cmd, rest)
conn = self.sock.context.wrap_socket(
conn, server_hostname=self.host, session=self.sock.session
)
return conn, size
新颖之处在于ntransfercmd
覆盖。
然后它的用法类似于ftplib.FTP_TLS
(以前的文章中有很多例子)。
覆盖connect
而不是使用sock
属性/设置器也是可行的。
解决方案 7:
我知道这个帖子已经很老了,ftp 也不像以前那么流行了,但无论如何,如果它能帮助到任何人,我愿意做出额外的贡献。我遇到了类似的情况,尝试使用被动模式下的 IMPLICIT(端口 990)ftps 连接到 ftp 服务器。在这种情况下,服务器在协商初始连接后,通常会提供一个新的主机 IP 地址和端口,可能与用于建立初始连接的 IP 地址和端口不同,实际的数据传输应该通过这些地址和端口进行。没什么大不了的,ftps 客户端(包括 python)可以处理这个问题,只有这个特定的服务器提供了一个不可路由的(可能是防火墙内部的)IP 地址。我注意到 FileZilla 连接没有问题,但 python ftplib 不能。然后我遇到了这个帖子:
如何在 ftplib 上用服务器地址替换不可路由的 IP 地址
这给了我线索。使用 Grzegorz Wierzowiecki 方法,我扩展了该线程中提到的方法并得出了这个结果,解决了我的问题。
import ftplib, os, sys
import socket
import ssl
FTPS_OBJ = ftplib.FTP_TLS
def conn_i_ftps(FTP_Site, Login_Name, Login_Password):
print "Starting IMPLICIT ftp_tls..."
ftps = tyFTP()
print ftps.connect(host=FTP_Site, port=990, timeout=120)
ftps.prot_p()
ftps.login(user=Login_Name, passwd=Login_Password)
print "Logged In"
ftps.retrlines('LIST')
# return ftps
class tyFTP(FTPS_OBJ):
def __init__(self, host='', user='', passwd='', acct='', keyfile=None, certfile=None, timeout=60):
FTPS_OBJ.__init__(self, host, user, passwd, acct, keyfile, certfile, timeout)
def connect(self, host='', port=0, timeout=-999):
if host != '':
self.host = host
if port > 0:
self.port = port
if timeout != -999:
self.timeout = timeout
try:
self.sock = socket.create_connection((self.host, self.port), self.timeout)
self.af = self.sock.family
self.sock = ssl.wrap_socket(self.sock, self.keyfile, self.certfile)
self.file = self.sock.makefile('rb')
self.welcome = self.getresp()
except Exception as e:
print e
return self.welcome
def makepasv(self):
print port #<---Show passively assigned port
print host #<---Show the non-routable, passively assigned IP
host, port = FTPS_OBJ.makepasv(self)
host = socket.gethostbyname(self.host) #<---- This changes the host back to the original IP that was used for the connection
print 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'
print host #<----Showing the original IP
return host, port
然后代码被像这样调用
FTP_Site = "ftp.someserver.com"
Login_Name = "some_name"
Login_Password = "some_passwd"
conn_i_ftps(FTP_Site, Login_Name, Login_Password)
我想人们可以在主机改回的行中使用 IF 语句来标识不可路由的地址,就像这样:
if host.split(".")[0] in (10, 192, 172):
host = socket.gethostbyname(self.host)
.
.
.
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