V13: Fix members while using basic auth. (#18206)

* Flow additional identities to new principal

* Add extension to more easily get member identity

* Ensure the member is used instead of the backoffice user in `MemberManager`

* Update snippet

* Fix the comment that I broke

* Update src/Umbraco.Web.Common/Extensions/MemberClaimsPrincipalExtensions.cs

Co-authored-by: Andy Butland <abutland73@gmail.com>

---------

Co-authored-by: Andy Butland <abutland73@gmail.com>

src/Umbraco.Core/EmbeddedResources/Snippets/LoginStatus.cshtml

@@ -5,7 +5,7 @@
 @using Umbraco.Extensions
 
 @{
-    var isLoggedIn = Context.User?.Identity?.IsAuthenticated ?? false;
+    var isLoggedIn = Context.User.GetMemberIdentity()?.IsAuthenticated ?? false;
     var logoutModel = new PostRedirectModel();
     // You can modify this to redirect to a different URL instead of the current one
     logoutModel.RedirectUrl = null;
@@ -15,7 +15,7 @@
 {
     <div class="login-status">
 
-        <p>Welcome back <strong>@Context?.User?.Identity?.Name</strong>!</p>
+        <p>Welcome back <strong>@Context.User?.GetMemberIdentity()?.Name</strong>!</p>
 
         @using (Html.BeginUmbracoForm<UmbLoginStatusController>("HandleLogout", new { RedirectUrl = logoutModel.RedirectUrl }))
         {

src/Umbraco.Web.Common/Extensions/HttpContextExtensions.cs

@@ -62,9 +62,16 @@ public static class HttpContextExtensions
         // Update the HttpContext's user with the authenticated user's principal to ensure
         // that subsequent requests within the same context will recognize the user
         // as authenticated.
-        if (result.Succeeded)
+        if (result is { Succeeded: true, Principal.Identity: not null })
         {
-            httpContext.User = result.Principal;
+            // We need to get existing identities that are not the backoffice kind and flow them to the new identity
+            // Otherwise we can't log in as both a member and a backoffice user
+            // For instance if you've enabled basic auth.
+            ClaimsPrincipal? authenticatedPrincipal = result.Principal;
+            IEnumerable<ClaimsIdentity> existingIdentities = httpContext.User.Identities.Where(x => x.IsAuthenticated && x.AuthenticationType != authenticatedPrincipal.Identity.AuthenticationType);
+            authenticatedPrincipal.AddIdentities(existingIdentities);
+
+            httpContext.User = authenticatedPrincipal;
         }
 
         return result;

src/Umbraco.Web.Common/Extensions/MemberClaimsPrincipalExtensions.cs

@@ -0,0 +1,18 @@
+using System.Security.Claims;
+using Microsoft.AspNetCore.Identity;
+
+namespace Umbraco.Extensions;
+
+public static class MemberClaimsPrincipalExtensions
+{
+    /// <summary>
+    /// Tries to get specifically the member identity from the ClaimsPrincipal
+    /// </summary>
+    /// <remarks>
+    /// The identity returned is the one with default authentication type.
+    /// </remarks>
+    /// <param name="principal">The principal to find the identity in.</param>
+    /// <returns>The default authenticated authentication type identity.</returns>
+    public static ClaimsIdentity? GetMemberIdentity(this ClaimsPrincipal principal)
+        => principal.Identities.FirstOrDefault(x => x.AuthenticationType == IdentityConstants.ApplicationScheme);
+}

src/Umbraco.Web.Common/Security/MemberManager.cs

@@ -1,4 +1,5 @@
 using System.Globalization;
+using System.Security.Claims;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.Extensions.Logging;
@@ -124,8 +125,11 @@ public class MemberManager : UmbracoUserManager<MemberIdentityUser, MemberPasswo
     /// <inheritdoc />
     public virtual bool IsLoggedIn()
     {
-        HttpContext? httpContext = _httpContextAccessor.HttpContext;
-        return httpContext?.User.Identity?.IsAuthenticated ?? false;
+        // We have to try and specifically find the member identity, it's entirely possible for there to be both backoffice and member.
+        ClaimsIdentity? memberIdentity = _httpContextAccessor.HttpContext?.User.GetMemberIdentity();
+
+        return memberIdentity is not null &&
+               memberIdentity.IsAuthenticated;
     }
 
     /// <inheritdoc />
@@ -181,23 +185,27 @@ public class MemberManager : UmbracoUserManager<MemberIdentityUser, MemberPasswo
     /// <inheritdoc />
     public virtual async Task<MemberIdentityUser?> GetCurrentMemberAsync()
     {
-        if (_currentMember == null)
+        if (_currentMember is not null)
         {
-            if (!IsLoggedIn())
-            {
-                return null;
-            }
-
-            _currentMember = await GetUserAsync(_httpContextAccessor.HttpContext?.User!);
+            return _currentMember;
         }
 
+        if (IsLoggedIn() is false)
+        {
+            return null;
+        }
+
+        // Create a principal the represents the member security context.
+        var memberPrincipal = new ClaimsPrincipal(_httpContextAccessor.HttpContext?.User.GetMemberIdentity()!);
+        _currentMember = await GetUserAsync(memberPrincipal);
+
         return _currentMember;
     }
 
     public virtual IPublishedContent? AsPublishedMember(MemberIdentityUser user) => _store.GetPublishedMember(user);
 
     /// <summary>
-    ///     This will check if the member has access to this path
+    /// This will check if the member has access to this path.
     /// </summary>
     /// <param name="path"></param>
     /// <returns></returns>