asn1parse.1s

Parse ASN.1 data

TLDR

Parse ASN.1 data

$ asn1parse -in [file.der]

Parse PEM encoded file

$ asn1parse -in [file.pem] -inform PEM

Parse with offset

$ asn1parse -in [file.der] -offset [100]

Show structure in detail

$ asn1parse -in [file.der] -dump

SYNOPSIS

asn1parse [-in file] [-inform format] [-offset n] [-dump] [options]

asn1parse is an OpenSSL diagnostic utility that parses ASN.1 (Abstract Syntax Notation One) encoded data. It displays the structure of certificates, keys, and other cryptographic objects in a human-readable format.
The tool is invaluable for debugging certificate issues, understanding data structures, and analyzing encoded data.

PARAMETERS

-in file

Input file

-inform format

Input format: PEM or DER

-out file

Output file

-noout

Don't output parsed structure

-offset n

Start parsing at offset n

-length n

Parse n bytes

-dump

Hex dump of content

-strparse offset

Parse nested structure at offset

-genstr string

Generate ASN.1 from string

CAVEATS

Requires understanding of ASN.1 structure. Output can be verbose for complex objects. Mainly for debugging, not routine use.

HISTORY

asn1parse is part of OpenSSL, which has been the standard cryptographic toolkit since the late 1990s.