Update the System.Net.Http integrations to support sending a contact address via the Form HTTP header

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpBuilder.cs

@@ -6,6 +6,7 @@
 
 using System.ComponentModel;
 using System.Net.Http.Headers;
+using System.Net.Mail;
 using System.Reflection;
 using OpenIddict.Client.SystemNetHttp;
 using Polly;
@@ -48,6 +49,38 @@ public sealed class OpenIddictClientSystemNetHttpBuilder
         return this;
     }
 
+    /// <summary>
+    /// Sets the contact address used in the "From" header that is attached
+    /// to the backchannel HTTP requests sent to the authorization server.
+    /// </summary>
+    /// <param name="address">The mail address.</param>
+    /// <returns>The <see cref="OpenIddictClientSystemNetHttpBuilder"/> instance.</returns>
+    public OpenIddictClientSystemNetHttpBuilder SetContactAddress(MailAddress address)
+    {
+        if (address is null)
+        {
+            throw new ArgumentNullException(nameof(address));
+        }
+
+        return Configure(options => options.ContactAddress = address);
+    }
+
+    /// <summary>
+    /// Sets the contact address used in the "From" header that is attached
+    /// to the backchannel HTTP requests sent to the authorization server.
+    /// </summary>
+    /// <param name="address">The mail address.</param>
+    /// <returns>The <see cref="OpenIddictClientSystemNetHttpBuilder"/> instance.</returns>
+    public OpenIddictClientSystemNetHttpBuilder SetContactAddress(string address)
+    {
+        if (string.IsNullOrEmpty(address))
+        {
+            throw new ArgumentException(SR.GetResourceString(SR.ID0366), nameof(address));
+        }
+
+        return SetContactAddress(new MailAddress(address));
+    }
+
     /// <summary>
     /// Replaces the default HTTP error policy used by the OpenIddict client services.
     /// </summary>
@@ -64,7 +97,7 @@ public sealed class OpenIddictClientSystemNetHttpBuilder
     }
 
     /// <summary>
-    /// Sets the product information used in the user agent header that is attached
+    /// Sets the product information used in the "User-Agent" header that is attached
     /// to the backchannel HTTP requests sent to the authorization server.
     /// </summary>
     /// <param name="information">The product information.</param>
@@ -80,7 +113,7 @@ public sealed class OpenIddictClientSystemNetHttpBuilder
     }
 
     /// <summary>
-    /// Sets the product information used in the user agent header that is attached
+    /// Sets the product information used in the "User-Agent" header that is attached
     /// to the backchannel HTTP requests sent to the authorization server.
     /// </summary>
     /// <param name="name">The product name.</param>

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpHandlers.Discovery.cs

@@ -19,6 +19,7 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
             PrepareGetHttpRequest<PrepareConfigurationRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareConfigurationRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareConfigurationRequestContext>.Descriptor,
+            AttachFromHeader<PrepareConfigurationRequestContext>.Descriptor,
             AttachQueryStringParameters<PrepareConfigurationRequestContext>.Descriptor,
             SendHttpRequest<ApplyConfigurationRequestContext>.Descriptor,
             DisposeHttpRequest<ApplyConfigurationRequestContext>.Descriptor,
@@ -38,6 +39,7 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
             PrepareGetHttpRequest<PrepareCryptographyRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareCryptographyRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareCryptographyRequestContext>.Descriptor,
+            AttachFromHeader<PrepareCryptographyRequestContext>.Descriptor,
             AttachQueryStringParameters<PrepareCryptographyRequestContext>.Descriptor,
             SendHttpRequest<ApplyCryptographyRequestContext>.Descriptor,
             DisposeHttpRequest<ApplyCryptographyRequestContext>.Descriptor,

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpHandlers.Exchange.cs

@@ -22,6 +22,7 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
             PreparePostHttpRequest<PrepareTokenRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareTokenRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareTokenRequestContext>.Descriptor,
+            AttachFromHeader<PrepareTokenRequestContext>.Descriptor,
             AttachBasicAuthenticationCredentials.Descriptor,
             AttachFormParameters<PrepareTokenRequestContext>.Descriptor,
             SendHttpRequest<ApplyTokenRequestContext>.Descriptor,

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpHandlers.Userinfo.cs

@@ -22,6 +22,7 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
             PrepareGetHttpRequest<PrepareUserinfoRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareUserinfoRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareUserinfoRequestContext>.Descriptor,
+            AttachFromHeader<PrepareUserinfoRequestContext>.Descriptor,
             AttachBearerAccessToken.Descriptor,
             AttachQueryStringParameters<PrepareUserinfoRequestContext>.Descriptor,
             SendHttpRequest<ApplyUserinfoRequestContext>.Descriptor,

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpHandlers.cs

@@ -9,6 +9,7 @@ using System.ComponentModel;
 using System.Diagnostics;
 using System.IO.Compression;
 using System.Net.Http.Headers;
+using System.Net.Mail;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Microsoft.Extensions.Primitives;
@@ -185,6 +186,47 @@ public static partial class OpenIddictClientSystemNetHttpHandlers
         }
     }
 
+    /// <summary>
+    /// Contains the logic responsible for attaching the contact address to the HTTP request.
+    /// </summary>
+    public sealed class AttachFromHeader<TContext> : IOpenIddictClientHandler<TContext> where TContext : BaseExternalContext
+    {
+        private readonly IOptionsMonitor<OpenIddictClientSystemNetHttpOptions> _options;
+
+        public AttachFromHeader(IOptionsMonitor<OpenIddictClientSystemNetHttpOptions> options)
+            => _options = options ?? throw new ArgumentNullException(nameof(options));
+
+        /// <summary>
+        /// Gets the default descriptor definition assigned to this handler.
+        /// </summary>
+        public static OpenIddictClientHandlerDescriptor Descriptor { get; }
+            = OpenIddictClientHandlerDescriptor.CreateBuilder<TContext>()
+                .AddFilter<RequireHttpMetadataUri>()
+                .UseSingletonHandler<AttachFromHeader<TContext>>()
+                .SetOrder(AttachUserAgentHeader<TContext>.Descriptor.Order + 1_000)
+                .SetType(OpenIddictClientHandlerType.BuiltIn)
+                .Build();
+
+        /// <inheritdoc/>
+        public ValueTask HandleAsync(TContext context)
+        {
+            if (context is null)
+            {
+                throw new ArgumentNullException(nameof(context));
+            }
+
+            // This handler only applies to System.Net.Http requests. If the HTTP request cannot be resolved,
+            // this may indicate that the request was incorrectly processed by another client stack.
+            var request = context.Transaction.GetHttpRequestMessage() ??
+                throw new InvalidOperationException(SR.GetResourceString(SR.ID0173));
+
+            // Attach the contact address specified in the options, if available.
+            request.Headers.From = _options.CurrentValue.ContactAddress?.ToString();
+
+            return default;
+        }
+    }
+
     /// <summary>
     /// Contains the logic responsible for attaching the query string parameters to the HTTP request.
     /// </summary>

src/OpenIddict.Client.SystemNetHttp/OpenIddictClientSystemNetHttpOptions.cs

@@ -6,6 +6,7 @@
 
 using System.Net;
 using System.Net.Http.Headers;
+using System.Net.Mail;
 using Polly;
 using Polly.Extensions.Http;
 
@@ -25,7 +26,13 @@ public sealed class OpenIddictClientSystemNetHttpOptions
             .WaitAndRetryAsync(4, attempt => TimeSpan.FromSeconds(Math.Pow(2, attempt)));
 
     /// <summary>
-    /// Gets or sets the product information used in the user agent header that is
+    /// Gets or sets the contact mail address used in the "From" header that is
+    /// attached to the backchannel HTTP requests sent to the authorization server.
+    /// </summary>
+    public MailAddress? ContactAddress { get; set; }
+
+    /// <summary>
+    /// Gets or sets the product information used in the "User-Agent" header that is
     /// attached to the backchannel HTTP requests sent to the authorization server.
     /// </summary>
     public ProductInfoHeaderValue? ProductInformation { get; set; }

src/OpenIddict.Validation.SystemNetHttp/OpenIddictValidationSystemNetHttpBuilder.cs

@@ -6,6 +6,7 @@
 
 using System.ComponentModel;
 using System.Net.Http.Headers;
+using System.Net.Mail;
 using System.Reflection;
 using OpenIddict.Validation.SystemNetHttp;
 using Polly;
@@ -48,6 +49,38 @@ public sealed class OpenIddictValidationSystemNetHttpBuilder
         return this;
     }
 
+    /// <summary>
+    /// Sets the contact address used in the "From" header that is attached
+    /// to the backchannel HTTP requests sent to the authorization server.
+    /// </summary>
+    /// <param name="address">The mail address.</param>
+    /// <returns>The <see cref="OpenIddictValidationSystemNetHttpBuilder"/> instance.</returns>
+    public OpenIddictValidationSystemNetHttpBuilder SetContactAddress(MailAddress address)
+    {
+        if (address is null)
+        {
+            throw new ArgumentNullException(nameof(address));
+        }
+
+        return Configure(options => options.ContactAddress = address);
+    }
+
+    /// <summary>
+    /// Sets the contact address used in the "From" header that is attached
+    /// to the backchannel HTTP requests sent to the authorization server.
+    /// </summary>
+    /// <param name="address">The mail address.</param>
+    /// <returns>The <see cref="OpenIddictValidationSystemNetHttpBuilder"/> instance.</returns>
+    public OpenIddictValidationSystemNetHttpBuilder SetContactAddress(string address)
+    {
+        if (string.IsNullOrEmpty(address))
+        {
+            throw new ArgumentException(SR.GetResourceString(SR.ID0366), nameof(address));
+        }
+
+        return SetContactAddress(new MailAddress(address));
+    }
+
     /// <summary>
     /// Replaces the default HTTP error policy used by the OpenIddict client services.
     /// </summary>
@@ -64,7 +97,7 @@ public sealed class OpenIddictValidationSystemNetHttpBuilder
     }
 
     /// <summary>
-    /// Sets the product information used in the user agent header that is attached
+    /// Sets the product information used in the "User-Agent" header that is attached
     /// to the backchannel HTTP requests sent to the authorization server.
     /// </summary>
     /// <param name="information">The product information.</param>
@@ -80,7 +113,7 @@ public sealed class OpenIddictValidationSystemNetHttpBuilder
     }
 
     /// <summary>
-    /// Sets the product information used in the user agent header that is attached
+    /// Sets the product information used in the "User-Agent" header that is attached
     /// to the backchannel HTTP requests sent to the authorization server.
     /// </summary>
     /// <param name="name">The product name.</param>
@@ -97,7 +130,7 @@ public sealed class OpenIddictValidationSystemNetHttpBuilder
     }
 
     /// <summary>
-    /// Sets the product information used in the user agent header that is attached
+    /// Sets the product information used in the "User-Agent" header that is attached
     /// to the backchannel HTTP requests sent to the authorization server based
     /// on the identity of the specified .NET assembly (name and version).
     /// </summary>

src/OpenIddict.Validation.SystemNetHttp/OpenIddictValidationSystemNetHttpHandlers.Discovery.cs

@@ -19,6 +19,7 @@ public static partial class OpenIddictValidationSystemNetHttpHandlers
             PrepareGetHttpRequest<PrepareConfigurationRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareConfigurationRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareConfigurationRequestContext>.Descriptor,
+            AttachFromHeader<PrepareConfigurationRequestContext>.Descriptor,
             AttachQueryStringParameters<PrepareConfigurationRequestContext>.Descriptor,
             SendHttpRequest<ApplyConfigurationRequestContext>.Descriptor,
             DisposeHttpRequest<ApplyConfigurationRequestContext>.Descriptor,
@@ -38,6 +39,7 @@ public static partial class OpenIddictValidationSystemNetHttpHandlers
             PrepareGetHttpRequest<PrepareCryptographyRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareCryptographyRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareCryptographyRequestContext>.Descriptor,
+            AttachFromHeader<PrepareCryptographyRequestContext>.Descriptor,
             AttachQueryStringParameters<PrepareCryptographyRequestContext>.Descriptor,
             SendHttpRequest<ApplyCryptographyRequestContext>.Descriptor,
             DisposeHttpRequest<ApplyCryptographyRequestContext>.Descriptor,

src/OpenIddict.Validation.SystemNetHttp/OpenIddictValidationSystemNetHttpHandlers.Introspection.cs

@@ -22,6 +22,7 @@ public static partial class OpenIddictValidationSystemNetHttpHandlers
             PreparePostHttpRequest<PrepareIntrospectionRequestContext>.Descriptor,
             AttachJsonAcceptHeaders<PrepareIntrospectionRequestContext>.Descriptor,
             AttachUserAgentHeader<PrepareIntrospectionRequestContext>.Descriptor,
+            AttachFromHeader<PrepareIntrospectionRequestContext>.Descriptor,
             AttachBasicAuthenticationCredentials.Descriptor,
             AttachFormParameters<PrepareIntrospectionRequestContext>.Descriptor,
             SendHttpRequest<ApplyIntrospectionRequestContext>.Descriptor,

src/OpenIddict.Validation.SystemNetHttp/OpenIddictValidationSystemNetHttpHandlers.cs

@@ -9,6 +9,7 @@ using System.ComponentModel;
 using System.Diagnostics;
 using System.IO.Compression;
 using System.Net.Http.Headers;
+using System.Net.Mail;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Microsoft.Extensions.Primitives;
@@ -186,6 +187,47 @@ public static partial class OpenIddictValidationSystemNetHttpHandlers
         }
     }
 
+    /// <summary>
+    /// Contains the logic responsible for attaching the contact address to the HTTP request.
+    /// </summary>
+    public sealed class AttachFromHeader<TContext> : IOpenIddictValidationHandler<TContext> where TContext : BaseExternalContext
+    {
+        private readonly IOptionsMonitor<OpenIddictValidationSystemNetHttpOptions> _options;
+
+        public AttachFromHeader(IOptionsMonitor<OpenIddictValidationSystemNetHttpOptions> options)
+            => _options = options ?? throw new ArgumentNullException(nameof(options));
+
+        /// <summary>
+        /// Gets the default descriptor definition assigned to this handler.
+        /// </summary>
+        public static OpenIddictValidationHandlerDescriptor Descriptor { get; }
+            = OpenIddictValidationHandlerDescriptor.CreateBuilder<TContext>()
+                .AddFilter<RequireHttpMetadataUri>()
+                .UseSingletonHandler<AttachFromHeader<TContext>>()
+                .SetOrder(AttachUserAgentHeader<TContext>.Descriptor.Order + 1_000)
+                .SetType(OpenIddictValidationHandlerType.BuiltIn)
+                .Build();
+
+        /// <inheritdoc/>
+        public ValueTask HandleAsync(TContext context)
+        {
+            if (context is null)
+            {
+                throw new ArgumentNullException(nameof(context));
+            }
+
+            // This handler only applies to System.Net.Http requests. If the HTTP request cannot be resolved,
+            // this may indicate that the request was incorrectly processed by another client stack.
+            var request = context.Transaction.GetHttpRequestMessage() ??
+                throw new InvalidOperationException(SR.GetResourceString(SR.ID0173));
+
+            // Attach the contact address specified in the options, if available.
+            request.Headers.From = _options.CurrentValue.ContactAddress?.ToString();
+
+            return default;
+        }
+    }
+
     /// <summary>
     /// Contains the logic responsible for attaching the query string parameters to the HTTP request.
     /// </summary>

src/OpenIddict.Validation.SystemNetHttp/OpenIddictValidationSystemNetHttpOptions.cs

@@ -6,6 +6,7 @@
 
 using System.Net;
 using System.Net.Http.Headers;
+using System.Net.Mail;
 using Polly;
 using Polly.Extensions.Http;
 
@@ -25,7 +26,13 @@ public sealed class OpenIddictValidationSystemNetHttpOptions
             .WaitAndRetryAsync(3, attempt => TimeSpan.FromSeconds(Math.Pow(2, attempt)));
 
     /// <summary>
-    /// Gets or sets the product information used in the user agent header that is
+    /// Gets or sets the contact mail address used in the "From" header that is
+    /// attached to the backchannel HTTP requests sent to the authorization server.
+    /// </summary>
+    public MailAddress? ContactAddress { get; set; }
+
+    /// <summary>
+    /// Gets or sets the product information used in the "User-Agent" header that is
     /// attached to the backchannel HTTP requests sent to the authorization server.
     /// </summary>
     public ProductInfoHeaderValue? ProductInformation { get; set; }