DER ASCII is a small human-editable language to emit DER (Distinguished Encoding Rules) or BER (Basic Encoding Rules) encodings of ASN.1 structures.

It provides two tools, ascii2der and der2ascii, to convert DER ASCII to a byte string and vice versa. To install them, run:

go get github.com/google/der-ascii/cmd/...

These tools may be used create test inputs by taking an existing DER or BER structure, disassembling it with der2ascii into DER ASCII, making adjustments, and assembling back into binary with ascii2der. This avoids having to manually fix up all the length prefixes. As a bonus, it acts as a human-readable view for DER structures.

For the language specification and basic examples, see language.txt. The samples directory includes more complex examples from real inputs.

This is not an official Google project.