A enhanced secure Blazor iFrame component with built-in origin validation, bidirectional messaging, navigation tracking, and comprehensive security features.
dotnet add package BlazorFrame@using BlazorFrame
<!-- Simple iframe with automatic security -->
<BlazorFrame Src="https://example.com" />
<!-- Production-ready configuration -->
<BlazorFrame Src="https://widget.example.com"
SecurityOptions="@securityOptions"
OnValidatedMessage="HandleMessage"
OnSecurityViolation="HandleViolation" />
@code {
private readonly MessageSecurityOptions securityOptions = new MessageSecurityOptions()
.ForProduction() // Strict security settings
.WithBasicSandbox() // Enable iframe sandboxing
.RequireHttps(); // Enforce HTTPS transport
private Task HandleMessage(IframeMessage message)
{
Console.WriteLine($"Received message from {message.Origin}: {message.Data}");
return Task.CompletedTask;
}
private Task HandleViolation(IframeMessage violation)
{
Console.WriteLine($"Security violation: {violation.ValidationError}");
return Task.CompletedTask;
};
}// Development environment - relaxed security
var devOptions = new MessageSecurityOptions()
.ForDevelopment()
.WithPermissiveSandbox();
// Production environment - strict security
var prodOptions = new MessageSecurityOptions()
.ForProduction()
.WithStrictSandbox()
.ValidateAndThrow();
// Payment widgets - maximum security
var paymentOptions = new MessageSecurityOptions()
.ForPaymentWidget();<BlazorFrame Src="https://widget.example.com"
CspOptions="@cspOptions"
OnCspHeaderGenerated="HandleCspGenerated" />
@code {
private readonly CspOptions cspOptions = new CspOptions()
.ForProduction()
.AllowFrameSources("https://widget.example.com")
.WithScriptNonce("secure-nonce-123");
private Task HandleCspGenerated(CspHeader cspHeader)
{
// Apply CSP header to HTTP response
// HttpContext.Response.Headers.Add(cspHeader.HeaderName, cspHeader.HeaderValue);
return Task.CompletedTask;
}
}Comprehensive CSP integration for defense-in-depth security:
All iframe messages are automatically validated for:
| Level | Description | Use Case |
|---|---|---|
| None | No restrictions | Trusted content only |
| Basic | Scripts + same-origin | Most trusted widgets |
| Permissive | + forms + popups | Interactive widgets |
| Strict | Scripts + same-origin only | Display widgets |
| Paranoid | Scripts only | Untrusted content |
Interactive Demo - Try different security configurations live
This project is licensed under the MIT License.
Built with :heart: for the Blazor community