Subject: [spring] Roman Danyliw's Discuss on draft-ietf-spring-sr-yang-29: (with DISCUSS and COMMENT)

From: Roman Danyliw via Datatracker <[email-masked]>
Date: Wed, 20 Jan 2021 19:13:01 -0800

Roman Danyliw has entered the following ballot position for
draft-ietf-spring-sr-yang-29: Discuss

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DISCUSS:
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Section 9.  The primary impact of the manipulating writable nodes appears to be
characterized as DoS.  Don’t the possible consequences also include the ability
to leak traffic outside the trusted domain or to route traffic through
arbitrary paths of the attackers choosing potentially enable on-path inspection
or manipulation of traffic; or avoidance of security controls?

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COMMENT:
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** Section 9.  Thanks for using the templated YANG Security Considerations.  A
nit on the references s/[RFC6536]/[RFC8341]/

** Section 9.  The following caution around readable nodes didn’t parse for me.
 Was the intent as follows:

OLD
The exposure of both local
   bindings and SID database will exposure segment routing paths that
   may be attacked.

NEW
The exposure of either the local bindings or SID database would provide an
attacker the segment routing paths and related topology information.

** Section 9.  Typo. s/a a/a/

** Section 9.  Typo. s/rediection/redirection/

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From: "Acee Lindem (acee)" <[email-masked]>
Date: Mon, 25 Jan 2021 19:27:43 +0000

Hi Roman,

Please see inline. 

On 1/20/21, 10:13 PM, "Roman Danyliw via Datatracker" <[email-masked]> wrote:

We have revised the writable nodes in the -30 version:

      /segment-routing/mpls/bindings - Modification to the local
      bindings could result in a Denial of Service (DoS) attack.  An
      attacker may also try to create segment conflicts (using the same
      segment identifier for different purposes) to redirect traffic
      within the trusted domain.  However, the traffic will remain
      within the trusted domain.  Redirection could be used to route the
      traffic to compromised nodes within the trusted domain or to avoid
      certain security functions (e.g., firewall).  Refer to section 8.1
      [RFC8402] for a discussion of the SR-MPLS trusted domain.

      /segment-routing/mpls/srgb - Modification of the Segment Routing
      Global Block (SRGB) could be used to mount a DoS attack.  For                                                         
      example, if the SRGB size is reduced to a very small value, a lot
      of existing segments could no longer be installed leading to a
      traffic disruption.

      /segment-routing/mpls/srlb - Modification of the Segment Routing
      Local Block (SRLB) could be used to mount a DoS attacks similar to
      those applicable to the SRGB.

      /segment-routing/mpls/label-blocks - Modification of the Segment
      Routing label blocks could be used to mount a DoS attack.

    OLD

    NEW

We've incorporated all your comments into the -30 version. 

Thanks,
Acee

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From: Roman Danyliw <[email-masked]>
Date: Tue, 26 Jan 2021 23:26:07 +0000

Hi Acee and Martin!

Thanks for the quick edits and additional explanation.  This text addressed all of my IESG review feedback.  I've cleared my ballot.

Regards,
Roman

> -----Original Message-----
> From: Acee Lindem (acee) <[email-masked]>
> Sent: Monday, January 25, 2021 2:28 PM
> To: Roman Danyliw <[email-masked]>; The IESG <[email-masked]>
> Cc: [email-masked]; [email-masked]; [email-masked];
> Joel Halpern <[email-masked]>
> Subject: Re: Roman Danyliw's Discuss on draft-ietf-spring-sr-yang-29: (with
> DISCUSS and COMMENT)
> 
> Hi Roman,
> 
> Please see inline.
> 
>