Re: [Lsr] New Version Notification for draft-wu-lsr-pce-discovery-security-support-00.txt

["Acee Lindem (acee)" <[e-mail]>]

Hi Qin, 

I believe it is a significant security exposure to include the actual keys in IGPs. What I was suggesting was to include an identifier of the key to be used.

Thanks,
Acee

On 8/24/18, 10:56 PM, "Qin Wu" <[e-mail]> wrote:

    Hi, Acee:
    -----邮件原件-----
    发件人: Acee Lindem (acee) [mailto:[e-mail]] 
    发送时间: 2018年8月24日 22:23
    收件人: Qin Wu; [e-mail]
    主题: Re: New Version Notification for draft-wu-lsr-pce-discovery-security-support-00.txt
    
    Hi Qin, 
    
    On 8/23/18, 11:03 PM, "Qin Wu" <[e-mail]> wrote:
    
        Hi, Folks:
        draft-wu-pce-discovery-pceps-support-07 has been resubmitted to LSR as draft-wu-lsr-pce-discovery-security-support-00 based on Chairs' suggestion.
        https://tools.ietf.org/html/draft-wu-lsr-pce-discovery-security-support-00
        This draft define IGP extension for PCEP security support, 
        1.TCP AO which has been published as RFC5295.
        2.PCEP over TLS which has been published as RFC8253 recently.
        
        One issue raised by chair is shared key support for TCP-AO, how do you get shared key?
    
    I guess my point was is that if you are distributing shared keys, you probably know whether or not TCP-AO is supported. Having said that, possibly the draft should include some sort of key-id for TCP-AO or TLS usage. For example, the key-chain name from RFC 8177. We don't need to decide now. 
    
    [Qin]: RFC5088 " OSPF Protocol Extensions for PCE discovery" said:
    "
       PCE discovery information is, by nature, fairly static and does not
       change with PCE activity.  Changes in PCE discovery information may
       occur as a result of PCE configuration updates, PCE
       deployment/activation, PCE deactivation/suppression, or PCE failure.
       Hence, this information is not expected to change frequently.
    "
    So security capability as part of PCE discovery information should also be static. 
    
    RFC5926 section 3.1 said:
    "
    In TCP-AO's manual key mode, this is a key shared by both peers, entered via some interface to their
    respective configurations.  The Master_Key is used as the seed for the KDF.
    "
    My impression TCP-AO relies on manual installation for shared key. But TLS has key management protocol to exchange shared key,e.g., one defined in RFC4279.
    We can either negotiate shared key for TCP-AO in the PCE discovery phase or during PCE configuration phase. For TLS usage, this is not needed, in my opinion.
    To support shared key negotiation during PCE discovery phase, we need to define a IGP PCED Sub-TLV for TCP-AO, I am not sure this is allowed according to RFC5088,
    It looks this new IGP PCEP TLV is a companion Sub-TLV for PCE-CAP-FLAGS Sub-TLV. 
    If adding a new Sub-TLV is allowed, we can add algorithm identifier and key chain name,key identifier altogether.
    
    If negotiating shared key during PCE configuration phase, it is clearly beyond scope of this draft.
    Thanks,
    Acee 
    
    
        we believe to support TCP-AO, RFC5296 should also be implemented, which provide PSK and associated ciphersuit.
        Let us know if you have any other opinion?
        
        -Qin
        -----邮件原件-----
        发件人: [e-mail] [mailto:[e-mail]] 
        发送时间: 2018年8月24日 10:57
        收件人: Daniel King; wangzitao; Dhruv Dhody; wangzitao; Diego R. Lopez; Diego Lopez; Qin Wu
        主题: New Version Notification for draft-wu-lsr-pce-discovery-security-support-00.txt
        
        
        A new version of I-D, draft-wu-lsr-pce-discovery-security-support-00.txt
        has been successfully submitted by Qin Wu and posted to the IETF repository.
        
        Name:		draft-wu-lsr-pce-discovery-security-support
        Revision:	00
        Title:		IGP extension for PCEP security capability support in the PCE discovery
        Document date:	2018-08-23
        Group:		Individual Submission
        Pages:		6
        URL:            https://www.ietf.org/internet-drafts/draft-wu-lsr-pce-discovery-security-support-00.txt
        Status:         https://datatracker.ietf.org/doc/draft-wu-lsr-pce-discovery-security-support/
        Htmlized:       https://tools.ietf.org/html/draft-wu-lsr-pce-discovery-security-support-00
        Htmlized:       https://datatracker.ietf.org/doc/html/draft-wu-lsr-pce-discovery-security-support
        
        
        Abstract:
           When a Path Computation Element (PCE) is a Label Switching Router
           (LSR) participating in the Interior Gateway Protocol (IGP), or even a
           server participating in IGP, its presence and path computation
           capabilities can be advertised using IGP flooding.  The IGP
           extensions for PCE discovery (RFC 5088 and RFC 5089) define a method
           to advertise path computation capabilities using IGP flooding for
           OSPF and IS-IS respectively.  However these specifications lack a
           method to advertise PCEP security (e.g., Transport Layer
           Security(TLS),TCP Authentication Option (TCP-AO)) support capability.
        
           This document proposes new capability flag bits for PCE-CAP-FLAGS
           sub-TLV that can be announced as attribute in the IGP advertisement
           to distribute PCEP security support information.
        
                                                                                          
        
        
        Please note that it may take a couple of minutes from the time of submission until the htmlized version and diff are available at tools.ietf.org.
        
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