RE: [fw-wiz] insecurity in internet connection thro cable modems

From: Bruce Platt (Bruce@ei3.com)
Date: 02/17/03

  • Next message: Noonan, Wesley: "RE: [fw-wiz] insecurity in internet connection thro cable modems" 
    From: Bruce Platt <Bruce@ei3.com>
To: "'Noonan, Wesley'" <Wesley_Noonan@bmc.com>, 'Dave Mitchell' <dmitchell@viawest.net>
Date: Sun, 16 Feb 2003 20:39:22 -0500

    It's not hard to generate a free SSL cert for a Netscreen if you have access
    to OPENSSL on a nice unix box.

    Here's quick step by step for use in securing a management interface:

    - Create a self-signed root certificate using openssl as follows:

    #openssl req -x509 -newkey rsa:1024 -keyout key.pem -out ca-public.pem

    remove the private key from it as follows:

    #openssl req -x509 -newkey rsa:1024 -keyout key.pem -out ca-public.pem

    - Create a local certificate request on the netscreen you want to manage.
    Fill in the ip address field with the internet ip of the device. This set's
    one of the Cn fields in the cert to the IP of the interface.

    - Save it somewhere with an appropriate name like untrust-interface-ip.pem.

    - Sign the certificate with the local root CA created there with a command
    like:

    #openssl x509 -req -in untrust-interface-ip.pem -CA ca-public.pem -CAkey
    ca-private.key \
     -CAcreateserial -out untrust-interface-ip.crt -days 730

    - This is now a valid certficate for the netscreen which can be loaded from
    the certicicates tab.

    - The next step which is to load the self-signed root CA ito the netscreen
    by using the laod button on the CA tab. Do this by remaming the
    ca-public.pem to a place where your browser can open as a file and rename
    the file ca-public.cer. Then load it into the netscreen from the
    Certificates, CA tab.

    Once you have loaded it you should reboot your netscreen. Then go to the
    Administration tab and enable the certificate for web management, and enable
    SSL for the interface you want to manage, by choosing the local certificate
    you loaded earlier. Also choose the ciper method you want to use

    Then go to the interfaces tab and enable SSL on that interface.

    At this point you can log into the netscreen via https, however, your
    browser is likely to "barf" due to the certificate coming from an untrusted
    root certifying authority. You can fix this in the next step.

    - Finally, open the capublic.cer file in your browser and open it. For
    Internet Explorer, the certificate import wizard starts on your PC and you
    should import this certificate into the "Trusted Root Certification
    Authorities" store. From now on, your browser will accept the certificate
    created in above and loaded as a valid certifcate from a trusted authority.

    - Go to the interfacees tab, and disable the Web UI. You can still manage
    the NS from the web via SSL, bot not via normal port 80 http.

    Simlar sets of commands will give you certs to use to negotiate the VPN.

    Just fine for use on a private network where no one needs to see the
    validity of the CA.

    Regards,

    -----Original Message-----
    From: Noonan, Wesley [mailto:Wesley_Noonan@bmc.com]
    Sent: Sunday, February 16, 2003 6:44 PM
    To: 'Dave Mitchell'
    Cc: 'Brian Ford'; firewall-wizards@honor.icsalabs.com
    Subject: RE: [fw-wiz] insecurity in internet connection thro cable
    modems

    Freely admiting that I am not a netscreen expert (and thus, I could have
    missed something in the config or docs), I found that I was unable to get it
    to function and create keys without needing a certificate, which is a hassle
    for small shops that want a VPN and don't want to pay for a certificate that
    only has local significance. I also found their documentation to be lacking.
    This was true for setting up SSH connections to manage the device as well.

    With the PIX I can generate my own keys in 10 seconds with a single command
    and I am off and running. 10-11 commands later, the VPN is up.

    Like I said, I just kind of feel like netscreen is about where the PIX was 2
    years ago. I happen to like the CLI of the PIX as well, but that probably
    has more to do with my router background than anything else. Beside, CLI
    preference is such a highly subjective situation anyway.

    HTH

    Wes Noonan, MCSE/CCNA/CCDA/NNCSS/Security+
    Senior QA Rep.
    BMC Software, Inc.
    (713) 918-2412
    wnoonan@bmc.com
    http://www.bmc.com

    > -----Original Message-----
    > From: Dave Mitchell [mailto:dmitchell@viawest.net]
    > Sent: Sunday, February 16, 2003 11:39
    > To: Noonan, Wesley
    > Cc: 'Brian Ford'; firewall-wizards@honor.icsalabs.com
    > Subject: Re: [fw-wiz] insecurity in internet connection thro cable modems
    >
    > Wes,
    > GlobalPro makes it easier to maintain a fleet of Netscreens. I'm
    > confused
    > as to why you feel their VPN support is lacking? I've been able to
    > interoperate
    > Netscreen IPSec with Cisco PIX, Cisco IOS, Checkpoint, Cisco VPN3k,
    > FreeSWAN;
    > just to name some. Support for preshared keys, x509 certs, ldap auth, and
    > securid
    > auth make me feel that Netscreen's IPSec has quite a few features, not to
    > mention
    > higher throughput due to their ASIC's.
    >
    > -dave
    >
    >
    > On Sat, Feb 15, 2003 at 01:27:51PM -0600, Noonan, Wesley wrote:
    > > Having used both, I strongly prefer a PIX. It is much easier to maintain
    > a
    > > bunch of PIXen than it is to maintain a bunch of netscreens. It's not
    > that
    > > the netscreens are bad, it is just that the TCO is too high to try to
    > > maintain a "fleet" of them. In addition, I find their (netscreen) VPN
    > > support to be... well... lacking. It is a very convoluted process, much
    > like
    > > the PIX was 2 years ago.
    > >
    > > HTH
    > >
    > > Wes Noonan, MCSE/CCNA/CCDA/NNCSS/Security+
    > > Senior QA Rep.
    > > BMC Software, Inc.
    > > (713) 918-2412
    > > wnoonan@bmc.com
    > > http://www.bmc.com
    > >
    > >
    > > > -----Original Message-----
    > > > From: Brian Ford [mailto:brford@cisco.com]
    > > > Sent: Saturday, February 15, 2003 12:56
    > > > To: firewall-wizards@honor.icsalabs.com
    > > > Cc: Dave Mitchell
    > > > Subject: Re: [fw-wiz] insecurity in internet connection thro cable
    > modems
    > > >
    > > > Dave,
    > > >
    > > > >More than
    > > > >likely, natting a home network behind a linksys soho router would be
    > > > >sufficient.
    > > >
    > > > Yet another security policy that begins with "more than likely". What
    > > > happens in the "likely" case when someone figures out where you are
    > and
    > > > wants to get at your stuff?
    > > >
    > > > >Putting in PIX 501's at someones home would be insane. If you have to
    > > > >administer
    > > > >it, a small Netscreen is much easier than dealing with PIX.
    > > >
    > > > Gee Dave. Why would it be insane to use a PIX?
    > > >
    > > > To set up a PIX at home all you need is the PIX. You don't need a PC
    > and
    > > > the setup disk that NetScreen ships.
    > > >
    > > > The 501 ships with a default "plug and play" configuration that for
    > many
    > > > installs (including folks sitting behind a cable modem) requires no
    > > > modification to get up and running.
    > > >
    > > > The PIX also supports Cisco AUS (Auto Update Server) so that security
    > > > policy, operating system image, and configuration updates can be
    > securely
    > > > downloaded to the PIX from a central site without end user
    > intervention.
    > > >
    > > > You said "a small Netscreen is much easier than dealing with PIX".
    > Have
    > > > you really tried both products? Could it be that you just don't like
    > > > PIX? Or that you just don't know about the PIX?
    > > >
    > > > Liberty for All,
    > > >
    > > > Brian
    > > >
    > > > At 12:00 PM 2/15/2003 -0500, firewall-wizards-
    > request@honor.icsalabs.com
    > > > wrote:
    > > > >Message: 5
    > > > >Date: Fri, 14 Feb 2003 14:03:11 -0700
    > > > >From: Dave Mitchell <dmitchell@viawest.net>
    > > > >To: "Perrymon, Josh L." <PerrymonJ@bek.com>
    > > > >Cc: "'Chapman, Justin T'" <JtChapma@bhi-erc.com>,
    > > > > "'firewall-wizards@honor.icsalabs.com '"
    > > > > <firewall-wizards@honor.icsalabs.com>
    > > > >Subject: Re: [fw-wiz] insecurity in internet connection thro cable
    > modems
    > > > >
    > > > >For normal users I'd recommend some sort of appliance filter or
    > firewall.
    > > > >More than
    > > > >likely, natting a home network behind a linksys soho router would be
    > > > >sufficient. If you
    > > > >want to do VPNing and what not, I think a Netscreen 5 would be the
    > best
    > > > >for the home
    > > > >firewall. Putting in PIX 501's at someones home would be insane. If
    > you
    > > > >have to administer
    > > > >it, a small Netscreen is much easier than dealing with PIX.
    > > > >
    > > > >-dave
    > > > >
    > > > >On Fri, Feb 14, 2003 at 10:42:16AM -0600, Perrymon, Josh L. wrote:
    > > > > > Yeah... I ( Security Professional ) would implement IPChains or a
    > PIX
    > > > @
    > > > > > home...
    > > > > > But don't you think Linux is completely out of the question for a
    > > > regular
    > > > > > end user?????
    > > > > >
    > > > > > I'm looking for an application based firewall for my VPN users..
    > > > > > So far ZONE ALARM is my choice.. I just wished I could integrate
    > it
    > > > with
    > > > > > the PIX VPN client like the concentrator can.
    > > > > >
    > > > > >
    > > > > >
    > > > > > Any Ideas??
    > > > > > -JP
    > > > > >
    > > > > > -----Original Message-----
    > > > > > From: Chapman, Justin T [mailto:JtChapma@bhi-erc.com]
    > > > > > Sent: Friday, February 07, 2003 11:29 AM
    > > > > > To: 'firewall-wizards@honor.icsalabs.com '
    > > > > > Subject: RE: [fw-wiz] insecurity in internet connection thro cable
    > > > > > modems
    > > > > >
    > > > > >
    > > > > > >
    > > > > > >ipchains is old ( for the previous Linux Kernel 2.2 ), iptables
    > > > > > >http://www.iptables.org would be a better choice.
    > > > > >
    > > > > > Agreed. If it's an option at all, choose iptables over ipchains.
    > > > It's
    > > > > more
    > > > > > flexable and it's a stateful packet filter, which makes for a
    > > > "smarter"
    > > > > > firewall. IPtables (and ipchains for that matter) can be a bit
    > > > > intimidating
    > > > > > to work with, especially if you're new to the syntax. If you're
    > going
    > > > to
    > > > > > "rolll your own" firewall, I would suggest searching
    > > > Google/Freshmeat.net
    > > > > > for "iptables generator". There are plenty of scripts/web
    > > > frontends/guis
    > > > > > that make creating simple "consumer-grade" firewalls a snap. One
    > that
    > > > I
    > > > > > particularly like is a cgi-based one at:
    > > > > >
    > > > > > http://morizot.net/firewall/gen/
    > > > > >
    > > > > > Good luck!
    > > > > >
    > > > > > --justin
    > > > > >
    > > >
    > > >
    > > > Brian Ford
    > > > Consulting Engineer
    > > > Corporate Consulting Engineering, Office of the Chief Technology
    > Officer
    > > > Cisco Systems, Inc.
    > > > http://www.cisco.com
    > > > e-mail: brford@cisco.com
    > > >
    > > > _______________________________________________
    > > > firewall-wizards mailing list
    > > > firewall-wizards@honor.icsalabs.com
    > > > http://honor.icsalabs.com/mailman/listinfo/firewall-wizards
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