asn1-parser.js/README.md

97 regels
2.7 KiB
Markdown

# BlueCrypt ASN.1 Parser
An ASN.1 parser in less than 100 lines of Vanilla JavaScript,
part of the BlueCrypt suite.
<br>
<small>(< 150 with newlines and comments)</small>
| < 100 lines of code | 1.1k gzipped | 2.5k minified | 4.7k with comments |
# Features
* [x] Complete ASN.1 parser
* [x] Parses x.509 certificates
* [x] PEM (base64-encoded DER)
* [x] VanillaJS, Zero Dependencies
* [x] Browsers (back to ES5.1)
* [ ] Node.js (built, publishing soon)
* [ ] Online Demo (built, publishing soon)
![](https://i.imgur.com/gV7w7bM.png)
<!--
# Demo
<https://coolaj86.com/demos/asn1-parser/>
-->
# Usage
```html
<script src="https://git.coolaj86.com/coolaj86/asn1-parser.js/raw/branch/master/asn1-parser.js"></script>
```
```js
'use strict";
var ASN1 = window.ASN1 // 62 lines
var Enc = window.Enc // 27 lines
var PEM = window.PEM // 6 lines
var pem = [ '-----BEGIN EC PRIVATE KEY-----'
+ 'MHcCAQEEIImMnaNu2jRjvQwVFnhhDw/KDYtS2Q6n8T5kJYniwY1UoAoGCCqGSM49'
+ 'AwEHoUQDQgAEIT1SWLxsacPiE5Z16jkopAn8/+85rMjgyCokrnjDft6Y/YnA4A50'
+ 'yZe7CnFsqeDcpnPbubP6cpYiVcnevNIYyg=='
+ '-----END EC PRIVATE KEY-----'
].join('\n');
var der = PEM.parseBlock(pem).der;
var json = ASN1.parse(der);
console.log(json);
```
```json
{ "type": 48 /*0x30*/, "lengthSize": 0, "length": 89
, "children": [
{ "type": 48 /*0x30*/, "lengthSize": 0, "length": 19
, "children": [
{ "type": 6, "lengthSize": 0, "length": 7, "value": <0x2a8648ce3d0201> },
{ "type": 6, "lengthSize": 0, "length": 8, "value": <0x2a8648ce3d030107> }
]
},
{ "type": 3, "lengthSize": 0, "length": 66,
"value": "<0x04213d5258bc6c69c3e2139675ea3928a409fcffef39acc8e0c82a24ae78c37ede98fd89c0e00e74c997bb0a716ca9e0dca673dbb9b3fa72962255c9debcd218ca>"
}
]
}
```
Note: `value` will be a `Uint8Array`, not a hex string.
### Optimistic Parsing
This is a dumbed-down, minimal ASN1 parser.
Rather than incorporating knowledge of each possible x509 schema
to know whether to traverse deeper into a value container,
it always tries to dive in (and backs out when parsing fails).
It is possible that it will produce false positives, but not likely
in real-world scenarios (PEM, x509, CSR, etc).
I'd be interested to hear if you encounter such a case.
### Zero Dependencies
> A little copying is better than a little dependency - Golang Proverbs by Rob Pike
Rather than requiring hundreds (or thousands) of lines of dependencies,
this library takes the approach of including from other libraries in its suite
to produce a small, focused file that does exactly what it needs to do.
# Legal
[BlueCrypt VanillaJS ASN.1 Parser](https://git.coolaj86.com/coolaj86/asn1-parser.js) |
MPL-2.0