RFR 8181841: A TSA server returns timestamp with precision higher than milliseconds

Weijun Wang weijun.wang at oracle.com
Tue Jun 13 01:48:23 UTC 2017



On 06/13/2017 09:44 AM, Weijun Wang wrote:
> Hi Michael
> 
> I cannot access ISO 8601 but according to
> https://en.wikipedia.org/wiki/GeneralizedTime:
> 
>> A GeneralizedTime is a time format in the ASN.1 notation. It consists
>> of a string value representing the calendar date, as defined in ISO
>> 8601, a time of day with an optional fractional seconds element and
>> the optional local time differential factor as defined in ISO 8601.
>>
>> In contrast to the UTCTime class of ASN.1 the GeneralizedTime uses a
>> four-digit representation of the year to avoid possible ambiguity.
>> Another difference is the possibility to encode time information of
>> any wanted precision via the fractional seconds element.
> 
> So my understanding is that ISO 8601 is only for "the optional local 
> time differential factor", and it does mention "any wanted precision".

Oh, ISO 8601 is for "the calendar date" and "the optional local time 
differential factor", but not "a time of day with an optional fractional 
seconds element".

--Max

> 
> In fact, I tried to generate a DER encoding of a GeneralizedTime with a 
> long fractional part and "openssl asn1parse" accepts it and displays all 
> the digits.
> 
> I can read X.680 but it does not mention any restriction.
> 
> Thanks
> Max
> 
> On 06/13/2017 01:07 AM, Michael StJohns wrote
>> The actual bound in GeneralizedTime is 6 digits of fractional time 
>> (according to ISO 8601) or 25 characters.  That should still continue
>> to be enforced.
>>



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