Re: [lamps] draft-housley-lamps-norevavail-00

[Russ Housley <[e-mail]>]

Tim:

The explicit flag is _very_ short.  When I made a bogus certificate to see how short, I was surprise to lear that OpenSSL already knows the OID...

Below is the whole certificate and the OpenSSL text output if you want to use some other tool to take a look.

Also, the explicit flag would allow the client to skip the OCSP query, even if it is going to fail soft.

Russ

= = = = = = = 

$openssl x509 -inform pem -in example_server_ecdsa.pem -text
Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            a5:b3:54:28:1b:b0:6e:51
        Signature Algorithm: ecdsa-with-SHA384
        Issuer: C = US, ST = VA, L = Herndon, O = Bogus CA
        Validity
            Not Before: May 19 17:57:30 2023 GMT
            Not After : May 26 17:57:30 2023 GMT
        Subject: CN = www.example.com, O = Example Corp., C = US
        Subject Public Key Info:
            Public Key Algorithm: id-ecPublicKey
                Public-Key: (384 bit)
                pub:
                    04:57:25:5a:14:09:8d:8e:55:46:13:cb:dc:c2:74:
                    aa:6b:ab:7a:e0:22:df:1b:88:9a:61:ac:dd:f5:d6:
                    6b:50:fc:83:d7:fe:cf:f4:27:11:fb:cf:35:8e:4a:
                    d1:30:ca:e0:2a:26:61:d2:ff:f1:91:dc:1d:b7:83:
                    61:23:82:fa:23:8b:c4:5a:a0:e6:3b:42:00:73:e1:
                    53:e7:2c:ae:ac:15:8c:90:85:22:95:d4:6f:0e:b3:
                    e8:0a:88:1a:7c:e2:6c
                ASN1 OID: secp384r1
                NIST CURVE: P-384
        X509v3 extensions:
            X509v3 No Revocation Available: 
                ..
            X509v3 Subject Alternative Name: 
                URI:http://www.example.com/
            X509v3 Key Usage: 
                Digital Signature
            X509v3 Extended Key Usage: 
                TLS Web Server Authentication
            Netscape Comment: 
                This certificate cannot be trusted for any purpose.
            X509v3 Subject Key Identifier: 
                84:3A:04:AC:34:73:61:19:39:9A:B6:45:6A:D3:7C:68:D3:5F:3D:DC
            X509v3 Authority Key Identifier: 
                F2:35:DB:34:04:DA:A5:55:F2:BD:69:03:99:B0:62:EC:E2:15:08:C1
    Signature Algorithm: ecdsa-with-SHA384
    Signature Value:
        30:65:02:31:00:d2:cf:b9:75:36:9b:4c:7a:bf:ef:ae:3a:6f:
        86:91:97:34:13:47:e4:2f:7d:b2:15:4e:bc:a6:25:91:f9:fb:
        04:2b:d8:9a:f1:86:e9:56:91:ef:18:93:e2:e8:5b:77:51:02:
        30:44:57:7c:d4:eb:57:44:c3:b8:1e:11:1d:87:ec:27:6b:0b:
        86:c7:34:4c:f5:0d:7e:08:52:59:e7:1a:9d:df:c2:38:2e:12:
        0d:58:9d:fd:7c:a0:ec:0d:43:42:bc:d3:be
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
$


> On May 19, 2023, at 1:23 PM, Tim Hollebeek <[e-mail]> wrote:
> 
> I was aware of that argument, but I was wondering if there was anything additional going on here that I had failed to think of.  With some people being very focused on certificate size, having an extension B that says “extension A intentionally left blank” perhaps needs some justification.  Or perhaps not.  On balance, I think it is best people have the option to be able to do so, for the reasons Rich mentions, but I have no strong feelings about it.
>  
> Since Mike mentioned browsers, when this last came up at CABF about seven years ago, we also answered the question about how browsers would handle this.  It’s actually trivial since they all mostly soft-fail on OCSP anyway.  In fact, in response to those discussions, Mozilla added code to ignore OCSP extensions for certificates with lifetimes less than some small number of days.  Some people even use it.
>  
> -Tim
>  
> From: Mike Ounsworth <[e-mail] <mailto:[e-mail]>> 
> Sent: Friday, May 19, 2023 12:48 PM
> To: Salz, Rich <rsalz=[e-mail] <mailto:rsalz=[e-mail]>>; Tim Hollebeek <[e-mail] <mailto:[e-mail]>>; Russ Housley <[e-mail] <mailto:[e-mail]>>; LAMPS <[e-mail] <mailto:[e-mail]>>
> Cc: Joe Mandel <[e-mail] <mailto:[e-mail]>>; Tomofumi Okubo <[e-mail] <mailto:[e-mail]>>
> Subject: RE: [lamps] draft-housley-lamps-norevavail-00
>  
> > In my security experience, it is always better to explicitly state something – the alarm did not sound – rather than have something implied by its absence
>  
> Fair enough.
>  
> ---
> Mike Ounsworth
>  
> From: Salz, Rich <rsalz=[e-mail] <mailto:rsalz=[e-mail]>> 
> Sent: Friday, May 19, 2023 10:44 AM
> To: Mike Ounsworth <[e-mail] <mailto:[e-mail]>>; Tim Hollebeek <[e-mail] <mailto:[e-mail]>>; Russ Housley <[e-mail] <mailto:[e-mail]>>; LAMPS <[e-mail] <mailto:[e-mail]>>
> Cc: Joe Mandel <[e-mail] <mailto:[e-mail]>>; Tomofumi Okubo <[e-mail] <mailto:[e-mail]>>
> Subject: [EXTERNAL] Re: [lamps] draft-housley-lamps-norevavail-00
>  
> WARNING: This email originated outside of Entrust.
> DO NOT CLICK links or attachments unless you trust the sender and know the content is safe.
> So yeah, exactly what Tim said: in what case is it helpful to explicitly state “No revocation info available” vs just leaving those extns out?
>  
> (Separate thread, separate issue)
>  
> In my security experience, it is always better to explicitly state something – the alarm did not sound – rather than have something implied by its absence – did the alarm sound? Do I know the CA is modern, did it make a mistake (been known to happen), etc.
>  
>  
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