Re: Call for Community Feedback: Retiring IETF FTP Service

Adam Roach <adam@nostrum.com> Mon, 16 November 2020 16:48 UTC

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Subject: Re: Call for Community Feedback: Retiring IETF FTP Service
To: Lars Eggert <lars@eggert.org>, Russ Housley <housley@vigilsec.com>
Cc: IETF <ietf@ietf.org>
References: <af6ab231024c478bbd28bbec0f9c69c9@cert.org> <0D41F3FD-BA1F-4716-A165-4FE7529431A9@vigilsec.com> <D26DCBB6-3997-4A73-BB46-867B4FD79BD2@eggert.org>
From: Adam Roach <adam@nostrum.com>
Message-ID: <27b80ed2-76fb-aee7-f22d-de56019e9aa9@nostrum.com>
Date: Mon, 16 Nov 2020 10:48:14 -0600
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I do not object to turning off the FTP service.

In the analysis, I think there are two costs to consider and one 
benefit. The benefit of leaving it online, of course, is that some small 
group of users still find utility in FTP. Keith has outlined some of the 
reasons that users might prefer FTP, and I think it would be worthwhile 
replicating these properties in HTTP where possible (e.g., ensuring 
access to RFCs at a stable URL in a raw format, and possibly even 
configuring WebDAV on those paths in a read-only mode to support remote 
filesystem mounting).

The costs, as I mention, are twofold. There's a small operational cost 
to keeping the FTP service up, running, and configured. For example, if 
there were some reason to restructure the way files are stored on the 
server, it's one additional service that needs to be updated. This is 
probably pretty small from a monetary perspective.

The far greater cost is that every additional public-facing service on a 
server adds attack surface for malicious parties. And for less popular 
protocols like FTP, the chance of maintainers proactively finding and 
patching security vulnerabilities in their servers is vanishingly small. 
(If there's some vibrant community actively and continuously 
contributing to an FTP server implementation, that changes the calculus 
a fair bit, but that seems fantastically unlikely.)

So, on balance, it looks like retiring a lightly-used service is the 
right choice.

/a

On 11/16/2020 4:51 AM, Lars Eggert wrote:
> On 2020-11-16, at 12:43, Russ Housley <housley@vigilsec.com> wrote:
>> I support turning off the FTP service at ietf.org.
> +1
>
> Lars