[NIFI-10955] In JASN1Reader allow preprocess of ASN files to reconcile unsupported features

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0-M1, 1.22.0
• Assignee: Tamas Palfy
• Reporter: Tamas Palfy
• Created: 06/Dec/22 19:02
• Updated: 12/Apr/23 03:23
• Resolved: 12/Apr/23 03:23

Description

The ASN specification allows the creation of valid ASN files that has features unrecognized by the asn1bean library we are using in JASN1Reader.

We can add a preprocessing step that creates modified versions of the provided ASN files (leaving the originals intact) that removes unsupported features in a way that makes them less strict but otherwise should still be compatible with incoming data.

Identified unsupported features:

• Certain constraint types
  • E.g.

    SomeType ::= INTEGER (ALL EXCEPT (0..15))
    

• Extension marker (a.k.a "ellipsis" or

  ...
  

  )

• • Can occur in constraints (e.g.

    SomeType ::= INTEGER (0..8,...,100..200)
    

    although

    SomeType ::= INTEGER (0..8,...)
    

    works)

• • or in type definitions (e.g.

    RootType::= SEQUENCE {
    	field1		INTEGER,
    	field2		INTEGER,
    	...,
    	field3      INTEGER
    }
    

    but this seems to work as well).

• Version brackets e.g.

  SomeType ::= SEQUENCE {
  	integerField1		INTEGER,
  	integerField2		INTEGER,
  	...,
  [[ -- from version 2
  	integerField3		INTEGER,
  	integerField4		INTEGER ]]
  }
  

  Seems to require extension marker as well.

Issue Links

• links to: GitHub Pull Request #6769