Question

我正在尝试在Twisted中编写SSH代理，它拦截SSH流量并将其转发到后端ssh服务器。

在前端我使用的是修改过的Conch，下面的代码子类为SSHSession：

def request_exec(self, data):
    cmd,data = common.getNS(data)
    log.msg('executing command "%s"' % cmd)
    prot = session.SSHSessionClient()
    prot.transport = self
    pf = _ProtocolFactory(prot)
    ep = endpoints.SSHCommandClientEndpoint.newConnection(reactor, cmd,
        USER, HOST, port=PORT, password=PASSWORD)
    ep.connect(pf)
    self.client = prot
    return 1

_ProtocolFactory类如下所示：

class _ProtocolFactory():
    """
    Factory to return the (existing) ssh session to pass to ssh command endpoint
    It does not actually function as a factory
    """

    def __init__(self, protocol):
        self.protocol = protocol


    def buildProtocol(self, addr):
        return self.protocol

整个事物接受来自用户的连接，我可以看到它成功登录到后端。

我遇到的问题是将stdout / stdin频道相互连接。后端连接上的SSHSession需要连接到前端的SSHSession。我试图将协议作为中间人，但我不认为这是正确的。

更新：单向数据传输正在使用自定义协议来转换客户端/服务器函数（因此dataReceived映射到写入，反之亦然：

class InBetween(protocol.Protocol):
    """
    This is the glue between the SSH server one one side and the
    SSH client on the other side
    """
    transport = None # Transport is the back-end the ssh-server
    client = None # Client is the front-end, the ssh-client
    buf = "" # buffer to send to back-end

    def write(self, bytes):
        # This is data going from the end-user to the back-end
        if not self.transport:
            self.buf += bytes
            return
        elif len(self.buf) and self.transport != None:
            self.transport.dataReceived(self.buf)
            self.buf = None
        self.transport.dataReceived(bytes)

   def dataReceived(self, data):
        # This is data going from the back-end to the end-user
        self.client.write(data)

使用Conch在Twisted中SSH到SSH代理

0 个答案: