/// <summary>
/// Forwards proxied headers onto current request
/// </summary>
/// <param name="builder"></param>
/// <param name="options">Enables the different forwarding options.</param>
/// <returns></returns>
public static IApplicationBuilder UseForwardedHeaders(this IApplicationBuilder builder, ForwardedHeadersOptions options)
{
if (builder == null)
{
throw new ArgumentNullException(nameof(builder));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
return builder.UseMiddleware<ForwardedHeadersMiddleware>(Options.Create(options));
}
public ForwardedHeadersMiddleware(RequestDelegate next, ILoggerFactory loggerFactory, IOptions<ForwardedHeadersOptions> options)
{
if (next == null)
{
throw new ArgumentNullException(nameof(next));
}
if (loggerFactory == null)
{
throw new ArgumentNullException(nameof(loggerFactory));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
_options = options.Value;
_logger = loggerFactory.CreateLogger<ForwardedHeadersMiddleware>();
_next = next;
}
public async Task XForwardedForForwardLimit(int limit, string header, string expectedIp, int expectedPort, string remainingHeader)
{
var assertsExecuted = false;
var builder = new WebHostBuilder()
.Configure(app =>
{
app.Use((context, next) =>
{
context.Connection.RemoteIpAddress = IPAddress.Parse("10.0.0.1");
context.Connection.RemotePort = 99;
return next();
});
var options = new ForwardedHeadersOptions
{
ForwardedHeaders = ForwardedHeaders.XForwardedFor,
ForwardLimit = limit,
};
options.KnownProxies.Clear();
options.KnownNetworks.Clear();
app.UseForwardedHeaders(options);
app.Run(context =>
{
Assert.Equal(expectedIp, context.Connection.RemoteIpAddress.ToString());
Assert.Equal(expectedPort, context.Connection.RemotePort);
Assert.Equal(remainingHeader, context.Request.Headers["X-Forwarded-For"].ToString());
assertsExecuted = true;
return Task.FromResult(0);
});
});
var server = new TestServer(builder);
var req = new HttpRequestMessage(HttpMethod.Get, "");
req.Headers.TryAddWithoutValidation("X-Forwarded-For", header);
await server.CreateClient().SendAsync(req);
Assert.True(assertsExecuted);
}
public void AllForwardsDisabledByDefault()
{
var options = new ForwardedHeadersOptions();
Assert.True(options.ForwardedHeaders == ForwardedHeaders.None);
Assert.Equal(1, options.ForwardLimit);
Assert.Equal(1, options.KnownNetworks.Count());
Assert.Equal(1, options.KnownProxies.Count());
}
public async Task XForwardedProtoOverrideLimitedByLoopback(string protoHeader, string forHeader, string remoteIp, bool loopback, string expected)
{
var assertsExecuted = false;
var builder = new WebHostBuilder()
.Configure(app =>
{
app.Use((context, next) =>
{
context.Connection.RemoteIpAddress = IPAddress.Parse(remoteIp);
return next();
});
var options = new ForwardedHeadersOptions
{
ForwardedHeaders = ForwardedHeaders.XForwardedProto | ForwardedHeaders.XForwardedFor,
ForwardLimit = 5,
};
if (!loopback)
{
options.KnownNetworks.Clear();
options.KnownProxies.Clear();
}
app.UseForwardedHeaders(options);
app.Run(context =>
{
Assert.Equal(expected, context.Request.Scheme);
assertsExecuted = true;
return Task.FromResult(0);
});
});
var server = new TestServer(builder);
var req = new HttpRequestMessage(HttpMethod.Get, "");
req.Headers.Add("X-Forwarded-Proto", protoHeader);
req.Headers.Add("X-Forwarded-For", forHeader);
await server.CreateClient().SendAsync(req);
Assert.True(assertsExecuted);
}
/// <summary>
/// Applies forwarded headers to their matching fields on the current request.
/// <para>
/// By convention, HTTP proxies forward information from the client in well-known HTTP headers.
/// The <see cref="ForwardedHeadersMiddleware"/> reads these headers and fills in the associated fields on HttpContext.
/// </para>
/// </summary>
/// <param name="builder">The <see cref="IApplicationBuilder" />.</param>
/// <param name="options">Enables the different forwarding options.</param>
/// <returns>A reference to <paramref name="builder" /> after the operation has completed.</returns>
public static IApplicationBuilder UseForwardedHeaders(this IApplicationBuilder builder, ForwardedHeadersOptions options)
{
if (builder == null)
{
throw new ArgumentNullException(nameof(builder));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
return(builder.UseMiddleware <ForwardedHeadersMiddleware>(Options.Create(options)));
}
