Add test for callback session persistence; extend authentication broker for refresh token hash initialization; enable config connection overrides

Author: sfmskywalker

src/apps/Elsa.ModularServer.Web/appsettings.json

@@ -59,6 +59,7 @@
             "EncryptionKey": "Q0hBTkdFX01FX1RPX0FfU0VDVVJFX1JBTkRPTV9LRVk="
           },
           "ExternalAuthentication": {
+            "AllowConfigurationConnectionOverrides": true,
             "LocalLogin": {
               "IsEnabled": true
             },

src/modules/Elsa.ExternalAuthentication/Services/ExternalAuthenticationBroker.cs

@@ -214,7 +214,8 @@ public async ValueTask<BrokerCallbackResult> CompleteCallbackAsync(string connec
                     StartedAt = clock.UtcNow,
                     LastRefreshedAt = clock.UtcNow,
                     ExpiresAt = clock.UtcNow.Add(options.Value.Lifetimes.MaximumSessionAge),
-                    RefreshExpiresAt = clock.UtcNow.Add(options.Value.Lifetimes.MaximumSessionAge)
+                    RefreshExpiresAt = clock.UtcNow.Add(options.Value.Lifetimes.MaximumSessionAge),
+                    CurrentRefreshTokenHash = CreateUnissuedRefreshTokenHash()
                 };
                 await sessionStore.SaveAsync(session, cancellationToken);
                 var code = CreateOpaqueValue();
@@ -511,6 +512,13 @@ private static void ValidateAuthorizationRequest(BrokerAuthorizationRequest requ
     }
     private static bool VerifyPkce(string challenge, string? verifier) => !string.IsNullOrWhiteSpace(verifier) && string.Equals(challenge, Base64Url(SHA256.HashData(Encoding.ASCII.GetBytes(verifier))), StringComparison.Ordinal);
     private static string CreateOpaqueValue() => Base64Url(RandomNumberGenerator.GetBytes(32));
+
+    /// <summary>
+    /// Sessions are persisted at callback completion, before the token issuer mints the first refresh token. The column is
+    /// required and uniquely indexed, so a per-session placeholder is stored until issuance rotates the real hash in. The
+    /// prefix keeps the value outside the hex-encoded hash space, so it can never be matched by a refresh-token lookup.
+    /// </summary>
+    private static string CreateUnissuedRefreshTokenHash() => $"unissued:{CreateOpaqueValue()}";
     private string Hash(string value) => handleHasher.Hash(value);
     private static string Base64Url(byte[] value) => Convert.ToBase64String(value).TrimEnd('=').Replace('+', '-').Replace('/', '_');
     private static Uri AppendCallbackParameters(Uri uri, string code, string? clientState)

test/integration/Elsa.ExternalAuthentication.IntegrationTests/Persistence/ExternalAuthenticationPersistenceTests.cs

@@ -241,6 +241,31 @@ public async Task DurableConcurrentReplacementUsesTheOldLinkIdAsAnAtomicGuard()
         }
     }
 
+    [Fact]
+    public async Task CallbackCompletionPersistsTheSessionBeforeAnyRefreshTokenIsIssued()
+    {
+        var identityResolver = Substitute.For<IExternalIdentityResolver>();
+        identityResolver.ResolveAsync(Arg.Any<ExternalIdentityResolutionContext>(), Arg.Any<CancellationToken>())
+            .Returns(ValueTask.FromResult(new ExternalIdentityResolution("user-a", false)));
+        var permissionGrantResolver = Substitute.For<IPermissionGrantResolver>();
+        permissionGrantResolver.ResolveAsync(Arg.Any<PermissionGrantResolutionContext>(), Arg.Any<CancellationToken>())
+            .Returns(ValueTask.FromResult(new PermissionGrantResult([], [])));
+        var adapter = new Broker.BrokerSecurityTests.RecordingAdapter
+        {
+            AuthenticationResult = new ExternalAuthenticationResult(new ExternalIdentity("https://issuer.example", "subject-a", EmptyClaims), EmptyClaims, [])
+        };
+        var broker = Broker.BrokerSecurityTests.CreateBroker(adapter, identityResolver: identityResolver, permissionGrantResolver: permissionGrantResolver, sessionStore: new EFCoreExternalAuthenticationSessionStore(new ExternalAuthenticationDbContextFactory(_services.GetRequiredService<IServiceScopeFactory>()), _clock));
+        await broker.InitiateExternalAsync(new BrokerAuthorizationRequest("studio", new Uri("https://studio.example/authentication/external/callback"), "code", "challenge", "S256", "/workflows", "contoso"), "tenant-a");
+
+        var result = await broker.CompleteCallbackAsync("contoso", adapter.CorrelationState!, new Dictionary<string, IReadOnlyCollection<string>> { ["state"] = [adapter.CorrelationState!] });
+
+        Assert.Null(result.Error);
+        await using var dbContext = await _dbContextFactory.CreateDbContextAsync();
+        var session = Assert.Single(await dbContext.ExternalAuthenticationSessions.ToListAsync());
+        Assert.False(string.IsNullOrEmpty(session.CurrentRefreshTokenHash));
+        Assert.Equal("user-a", session.UserId);
+    }
+
     private static IReadOnlyDictionary<string, IReadOnlyCollection<string>> EmptyClaims { get; } = new Dictionary<string, IReadOnlyCollection<string>>();
 
     private static IdentityProviderConnection CreateConnection(string id = "connection-a") => new()