Show SAN extension as string not HEX

[RufusJWB]

It would be helpful, if the SAN extension wouldn't be shown as HEX but as ASCII strings:

[Crypt32]

Unfortunately, it is not possible at the moment and is known limitation. SAN extension is a GeneralName which is a choice of implicitly tagged alternative names:

GeneralName ::= CHOICE 
{
  otherName              [0] IMPLICIT OtherName,
  rfc822Name             [1] IMPLICIT IA5STRING,
  dNSName                [2] IMPLICIT IA5STRING,
  x400Address            [3] IMPLICIT SeqOfAny,       --Not supported
  directoryName          [4] EXPLICIT ANY,    
  ediPartyName           [5] IMPLICIT SeqOfAny,
  uniformResourceLocator [6] IMPLICIT IA5STRING,
  iPAddress              [7] IMPLICIT OCTETSTRING,
  registeredID           [8] IMPLICIT EncodedObjectID --Not supported
}

ASN.1 editor decodes arbitrary data and do not attempt to parse complex data types. That is, when decoding the SAN extension, the tool has no idea what it is decoding and can't decode implicitly tagged types, because context is unknown. In order to properly represent SAN choice, the tool must have a context and use complex heurestics and predefined tables of known X.509 types. For example, authority key identifier extension uses implicitly tagged choice. But it can be a hash of issuer public key, which is a hex string, not encoded ASCII characters.

The only exception was made for uniformResourceLocator because I never faced so large choice in X.509 apart from URI alternative name, thus I'm decoding it as text at my own risk.

[RufusJWB]

Do I understand it correctly, that the ASN.1 editor would need to know the x509 grammar to decode the SAN extension correctly?

[ralienpp]

@Crypt32, would it be possible to add a context menu entry called View as text?

Asn1Editor doesn't need to be extended in way that makes it capable of figuring out what data it is looking at - the decision is delegated to a human.

It would be beneficial for my use case, where I have a file open for many hours at a time - a few manual clicks aren't a burden, but the ability to see the data as text in multiple nodes would surely make my life easier.

p.s. I don't mean that this should be done specifically for the SAN extension, but to any node in the tree.

[Crypt32]

Implemented in v23.12.17