如何使用powershell连接到tcp套接字以发送和接收数据？

Question

我写了一个小的Powershell脚本.

它使用.Net System.IO.StreamReader和System.IO.StreamWriter从/向TCP套接字读取和写入数据.

我想用它和发送/接收命令连接到套接字telnet样式.

我试图从System.IO.StreamReader读取带有ReadLine()方法的行,但是来自服务器的数据可能没有及时到达(？)或IDK.我没有使用异步命令.请帮助我!

这是我的脚本:

$FTPServer = "localhost"
$FTPPort = "21"

$tcpConnection = New-Object System.Net.Sockets.TcpClient($FTPServer, $FTPPort)
$tcpStream = $tcpConnection.GetStream()
$reader = New-Object System.IO.StreamReader($tcpStream)
$writer = New-Object System.IO.StreamWriter($tcpStream)
$writer.AutoFlush = $true

while ($tcpConnection.Connected)
{
    while ($tcpStream.DataAvailable)
    {
        $reader.ReadLine()
    }

    if ($tcpConnection.Connected)
    {
        Write-Host -NoNewline "prompt> "
        $command = Read-Host

        if ($command -eq "escape")
        {
            break
        }

        $writer.WriteLine($command) | Out-Null
    }
}

$reader.Close()
$writer.Close()
$tcpConnection.Close()

这是输出:

PS C:\Windows\System32\WindowsPowerShell\v1.0> test.ps1
220 Microsoft FTP Service
prompt> user username
331 Password required
prompt> pass password
230-Directory has 58,145,996,800 bytes of disk space available.
prompt> 
230 User logged in.
500 Command not understood.
prompt> help
214-The following commands are recognized (* ==>'s unimplemented).
    ABOR 
    ACCT 
    ADAT *
    ALLO 
    APPE 
    AUTH 
    CCC 
    CDUP 
    CWD 
    DELE 
    ENC *
    EPRT 
    EPSV 
    FEAT 
    HELP 
    HOST 
    LANG 
    LIST 
    MDTM 
    MIC *
    MKD 
    MODE 
    NLST 
    NOOP 
    OPTS 
    PASS 
    PASV 
    PBSZ 
    PORT 
    PROT 
    PWD 
    QUIT 
    REIN 
    REST 
    RETR 
    RMD 
    RNFR 
    RNTO 
    SITE 
prompt> escape

PS C:\Windows\System32\WindowsPowerShell\v1.0>

Answer 1

尝试使用缓冲区来读取响应.代码如下所示:

$tcpConnection = New-Object System.Net.Sockets.TcpClient($FTPServer, $FTPPort)
$tcpStream = $tcpConnection.GetStream()
$reader = New-Object System.IO.StreamReader($tcpStream)
$writer = New-Object System.IO.StreamWriter($tcpStream)
$writer.AutoFlush = $true

$buffer = new-object System.Byte[] 1024
$encoding = new-object System.Text.AsciiEncoding 

while ($tcpConnection.Connected)
{
    while ($tcpStream.DataAvailable)
    {

        $rawresponse = $reader.Read($buffer, 0, 1024)
        $response = $encoding.GetString($buffer, 0, $rawresponse)   
    }

    if ($tcpConnection.Connected)
    {
        Write-Host -NoNewline "prompt> "
        $command = Read-Host

        if ($command -eq "escape")
        {
            break
        }

        $writer.WriteLine($command) | Out-Null
    }
    start-sleep -Milliseconds 500
}

$reader.Close()
$writer.Close()
$tcpConnection.Close()