Re: Port Zero

From: STRAMBO (Strambo_at_t-online.de)
Date: 07/17/05

  • Next message: Ron: "Re: Port Zero"
    To: <incidents@securityfocus.com>
    Date: Sun, 17 Jul 2005 19:57:48 +0200
    
    

    Hi,

    Port 0 is officially a reserved port in TCP/IP networking, meaning that it
    should not be used for any TCP or UDP network communications.

    However, port 0 sometimes takes on a special meaning in network programming,
    particularly Unix socket programming. In this environment, port 0 is a
    programming technique for specifying system-allocated (dynamic) ports.

    Instead of "hard-coding" a particular port number, or writing code that
    searches for an open port, Unix programmers simply specify port 0 as a
    connection parameter. That triggers the operating system to automatically
    search for and return the next available port in the dynamic port number
    range.

    This programming technique does not work the same way in Microsoft Windows
    as it does in Unix.

    Best regards
    Strambo

    ----- Original Message -----
    From: <omibaba@gmail.com>
    To: <incidents@securityfocus.com>
    Sent: Saturday, July 16, 2005 6:14 AM
    Subject: Port Zero

    > Active Connections
    >
    > Proto Local Address Foreign Address State
    > TCP 0.0.0.0:135 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:445 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1025 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1028 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1054 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1307 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1344 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1445 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1447 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1452 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1453 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1455 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1460 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1465 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1466 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1469 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1491 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1496 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1498 0.0.0.0:0 LISTENING
    > TCP 0.0.0.0:1507 0.0.0.0:0 LISTENING
    >
    > Above is the output of netstat -an |more
    >
    > Guys / Gals Do you know what means port zero in Windoze Platform ? I know
    the answer but jst wanted to know anyone has a better explaination.
    >
    > In Unix Family port zero is used for socket programming but not the same
    in Windoze family.
    >
    > I have asked this question in many programs of mine in CEH - Certfied
    Ethical Hacking but still awaiting for answers. Lemme see if can get some
    answers for this post!!!!
    >
    > Ciao
    >
    > Baba
    > CEO
    > Appsec


  • Next message: Ron: "Re: Port Zero"

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