# node-asn1

**Repository Path**: mirrors_addons/node-asn1

## Basic Information

- **Project Name**: node-asn1
- **Description**: Contains parsers and serializers for ASN.1 (currently BER only)
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-05-03
- **Last Updated**: 2025-08-30

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# node-asn1

node-asn1 is a library for encoding and decoding ASN.1 datatypes in pure JS.
Currently BER encoding is supported; at some point I'll likely have to do DER.

## Usage

Mostly, if you're *actually* needing to read and write ASN.1, you probably don't
need this readme to explain what and why.  If you have no idea what ASN.1 is,
see [A Layman's Guide to a Subset of ASN.1, BER, and DER](layman.asc).

The source is pretty much self-explanatory, and has read/write methods for the
common types out there.

### Decoding

The following reads an ASN.1 sequence with a boolean.

    var Ber = require('asn1').Ber;

    var reader = new Ber.Reader(Buffer.from([0x30, 0x03, 0x01, 0x01, 0xff]));

    reader.readSequence();
    console.log('Sequence len: ' + reader.length);
    if (reader.peek() === Ber.Boolean)
      console.log(reader.readBoolean());

### Encoding

The following generates the same payload as above.

    var Ber = require('asn1').Ber;

    var writer = new Ber.Writer();

    writer.startSequence();
    writer.writeBoolean(true);
    writer.endSequence();

    console.log(writer.buffer);

## Installation

    npm install asn1

## License

MIT.

## Bugs

See <https://github.com/joyent/node-asn1/issues>.