API Documentation

AntiSSRF .NET Library

The AntiSSRF .NET Library is a library for C# applications using .NET that provides robust URL validation and HTTP request protection to prevent SSRF vulnerabilities in code. It is designed as an easy, drop-in library with minimal impact on the engineering team, implemented both as an HttpMessageHandler for use with HttpClient and as a static URL validator, depending on use case.

Usage Instructions

The AntiSSRF Library provides validation for different scenarios based on your trust requirements:

Use Case Description Documentation Link
General Case The untrusted URL can belong to any domain or an untrusted domain. AntiSSRFPolicy
Azure Key Vault Domain The untrusted URL must be an Azure Key Vault endpoint. URIValidator.InAzureKeyVaultDomain
Azure Storage Domain The untrusted URL must be an Azure Storage endpoint. URIValidator.InAzureStorageDomain
Allowlist of Trusted Domains The untrusted URL must belong to a specific, trusted domain. URIValidator.InDomain

Classes

Class Description
AntiSSRFPolicy Represents a customizable security policy and provides an AntiSSRFHandler to ensure all outgoing HttpClient requests match the security policy.
AntiSSRFHandler An HttpMessageHandler that enforces the AntiSSRFPolicy on all outgoing requests.
IPAddressRanges Provides predefined IP address ranges for use with AntiSSRF policies.
URIValidator Provides static methods for validating the hostname and protocol of URLs.

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