Re: asn1Decoding(1) fails to decode a CHOICE?

[Nikos Mavrogiannopoulos]

On 10/06/2012 08:42 PM, Ivan Shmakov wrote:


>  >> The integer is 42 decimal, or 2A hexadecimal, and it's stored as the
>  >> third (and the last) octet of the sequence.
> 
>  > I don't see any integer there with "openssl asn1parse".
>       AIUI, X.690 §8.1.2 specifies that there could only be one tag
>       per value, and the CHOICE above uses “private” tags (PRIVATE 0,
>       PRIVATE 1) to distinguish the members, instead of the
>       “universal”, type-encoding tags (such as INTEGER = UNIVERSAL 2.)

>       There isn't much choice here, actually, as the types of these

>       CHOICE members just happen to coincide.


It looks like a corner case indeed. I do not know what should be the
encoding in that case. Do you have any use-case that is affected by this
behavior or it is a test example?

>  > Could be but I've never needed that tool.  Maybe given its
>  > limitations it is a good idea to even remove it.  When I need to
>  > generate structures I use libtasn1 directly.
>       Honestly, I'd hesitate to write C code when the task at hand
>       could be accomplished with a higher-level language, such as
>       Shell (or Perl), which seem to speak in favor of retaining such
>       command-line tools.

>       (I hope to check if these tools could be improved by some simple
>       changes.)

Indeed. Would you be interested into augmenting this application? I
don't think it is hard to make it a practical tool to generate structures.

regards,
Nikos