asn.1 DER 编码隐式序列

Question

I am trying to encode the below ASN.1 grammar in DER format.

BuiltInStandardAttributes ::= SEQUENCE {
    organizational-unit-names [6] IMPLICIT OrganizationalUnitNames OPTIONAL 
    } 
    
OrganizationalUnitNames ::= SEQUENCE SIZE (1..ub-organizational-units)
                             OF OrganizationalUnitName

OrganizationalUnitName ::= PrintableString (SIZE
                    (1..ub-organizational-unit-name-length))
                

In the sample data, I have 2 PrintableString s "be" and "pai"

I tried the encoding as

SEQUENCE (1 elem)
  [6] (2 elem)
    PrintableString be
    PrintableString pai

30 0B A6 09 13 02 62 65 13 03 70 61 69

Is this correct? Here, how do I specify the inner SEQUENCE is IMPLICIT ?

Answer 1

You can test your encoding against your schema at https://asn1.io/PKI-Inspector .

For example, if

the inline IMPLICT is not specified

but your schema specifies the AUTOMATIC TAGS in the module definition, your encoding will match the schema . If your module specifies the EXPLICIT TAGS the encoding won't match .