OpenSSL "ans1parse" - Wrap of Primitive Field

Q

Can I wrap a primitive field into a BIT STRING or OCTET STRING field with the OpenSSL "asn1parse" command?

✍: FYIcenter.com

A

Yes, you can wrap any ASN.1 primitive field into a BIT STRING or OCTET STRING field using the BITWRAP or OCTWRAP modifiers using the OpenSSL "asn1parse" command.

The test below gives some demonstrations of wrapping primitive field into BIT STRING or OCTET STRING:

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr BITWRAP,INTEGER:127 -dump
    0:d=0  hl=2 l=   4 prim: BIT STRING
      0000 - 00 02 01 7f                                       ....

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,INTEGER:127
    0:d=0  hl=2 l=   3 prim: OCTET STRING      [HEX DUMP]:02017F

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,INTEGER:128
    0:d=0  hl=2 l=   4 prim: OCTET STRING      [HEX DUMP]:02020080
    
C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,INTEGER:-0x01
    0:d=0  hl=2 l=   3 prim: OCTET STRING      [HEX DUMP]:0201FF

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,IA5STRING:"1234"
    0:d=0  hl=2 l=   6 prim: OCTET STRING      [HEX DUMP]:160431323334

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,OBJECT:2.5.4.3
    0:d=0  hl=2 l=   5 prim: OCTET STRING      [HEX DUMP]:0603550403

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,BITSTRING:"1234"
    0:d=0  hl=2 l=   7 prim: OCTET STRING      [HEX DUMP]:03050031323334

C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,FORMAT:HEX,BITSTRING:41424344
    0:d=0  hl=2 l=   7 prim: OCTET STRING      [HEX DUMP]:03050041424344
    
C:\Users\fyicenter>\local\openssl\openssl 
   asn1parse -genstr OCTWRAP,FORMAT:HEX,OCTETSTRING:41424244
    0:d=0  hl=2 l=   6 prim: OCTET STRING      [HEX DUMP]:040441424244

 

OpenSSL "ans1parse" - DER (Distinguished Encoding Rules)

OpenSSL "ans1parse" - BITWRAP and OCTWRAP Modifiers

OpenSSL "ans1parse" Command

⇑⇑ OpenSSL Tutorials

2016-09-28, 4771👍, 0💬