---
title: X509
url: 'https://brendo.org/wp-content/plugins/two-factor-provider-webauthn/vendor/sop/x509'
markdown: 'https://brendo.org/wp-content/plugins/two-factor-provider-webauthn/vendor/sop/x509.md'
date: '2026-04-06'
description: 'X.509 A PHP library for X.509 public key certificates, attribute certificates, certification requests and certification path validation. Introduction This library provides a pure PHP implementation of X.509 certificates. The class hierarchy adapts to the ASN.1 types, which makes it easy to use …'
---

# X.509

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A PHP library for X.509 public key certificates, attribute certificates, certification requests and certification path validation.

## Introduction

This library provides a pure PHP implementation of X.509 certificates. The class hierarchy adapts to the ASN.1 types, which makes it easy to use corresponding RFC’s as a reference documentation.

## Features

- X.509 certificates ([RFC 5280](https://tools.ietf.org/html/rfc5280)) 
    - Certificate decoding and encoding
    - Certificate signing
- Certification requests ([PKCS #10](https://tools.ietf.org/html/rfc2986)) 
    - CSR decoding and encoding
- Certification path 
    - Path building
    - Path validation
- Attribute certificates ([RFC 5755](https://tools.ietf.org/html/rfc5755)) 
    - AC decoding and encoding
    - AC signing

## Requirements

- PHP >=7.2
- gmp
- [sop/asn1](https://github.com/sop/asn1)
- [sop/x501](https://github.com/sop/x501)
- [sop/crypto-types](https://github.com/sop/crypto-types)
- [sop/crypto-bridge](https://github.com/sop/crypto-bridge)
- [sop/crypto-encoding](https://github.com/sop/crypto-encoding)

## Installation

This library is available on [Packagist](https://packagist.org/packages/sop/x509).

```
composer require sop/x509
```

## Code examples

Examples are located in [`/examples`](https://github.com/sop/x509/tree/master/examples)directory.

- [Create a CA certificate](https://github.com/sop/x509/blob/master/examples/create-ca-cert.php)
- [Create a CSR](https://github.com/sop/x509/blob/master/examples/create-csr.php)
- [Issue a certificate](https://github.com/sop/x509/blob/master/examples/issue-cert.php)
- [Validate a certification path](https://github.com/sop/x509/blob/master/examples/path-validate.php)

## License

This project is licensed under the MIT License.

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