Fixed bug. Internal redirect was hard coded, changed to match quality of other providers and remove hard coded paths.

Is now able to operate with controllers not named "Account" with any view/path instead of the previous hard coded path.

Owin.Security.Providers/ArcGISOnline/ArcGISOnlineAuthenticationHandler.cs

@@ -34,6 +34,7 @@ namespace Owin.Security.Providers.ArcGISOnline
             try
             {
                 string code = null;
+                string state = null;
 
                 IReadableStringCollection query = Request.Query;
                 IList<string> values = query.GetValues("code");
@@ -41,17 +42,33 @@ namespace Owin.Security.Providers.ArcGISOnline
                 {
                     code = values[0];
                 }
+                values = query.GetValues("state");
+                if (values != null && values.Count == 1)
+                {
+                    state = values[0];
+                }
+
+                properties = Options.StateDataFormat.Unprotect(state);
+                if (properties == null)
+                {
+                    return null;
+                }
+                // OAuth2 10.12 CSRF
+                if (!ValidateCorrelationId(properties,logger))
+                {
+                    return new AuthenticationTicket(null, properties);
+                }
             
                 string requestPrefix = Request.Scheme + "://" + Request.Host;
                 string redirectUri = requestPrefix + Request.PathBase + Options.CallbackPath;
 
                 // Build up the body for the token request
                 var body = new List<KeyValuePair<string, string>>();
+                body.Add(new KeyValuePair<string, string>("grant_type", "authorization_code"));
                 body.Add(new KeyValuePair<string, string>("code", code));
                 body.Add(new KeyValuePair<string, string>("redirect_uri", redirectUri));
                 body.Add(new KeyValuePair<string, string>("client_id", Options.ClientId));
                 body.Add(new KeyValuePair<string, string>("client_secret", Options.ClientSecret));
-                body.Add(new KeyValuePair<string, string>("grant_type", "authorization_code"));
                 
                 // Request the token
                 var requestMessage = new HttpRequestMessage(HttpMethod.Post, Options.Endpoints.TokenEndpoint);
@@ -104,11 +121,7 @@ namespace Owin.Security.Providers.ArcGISOnline
                     Request.Host +
                     Request.PathBase;
 
-                context.Properties = new AuthenticationProperties
-                {
-                    RedirectUri = baseUri +
-                    "/Account/ExternalLoginCallback"
-                };
+                context.Properties = properties;
               
                 await Options.Provider.Authenticated(context);
 
@@ -146,7 +159,14 @@ namespace Owin.Security.Providers.ArcGISOnline
                 string redirectUri =
                     baseUri +
                     Options.CallbackPath;
+                AuthenticationProperties properties=challenge.Properties;
+                if (string.IsNullOrEmpty(properties.RedirectUri))
+                {
+                    properties.RedirectUri = currentUri;
+                }
 
+                GenerateCorrelationId(properties);
+                string state = Options.StateDataFormat.Protect(properties);
                 // comma separated
                 string scope = string.Join(",", Options.Scope);
 
@@ -154,7 +174,8 @@ namespace Owin.Security.Providers.ArcGISOnline
                     Options.Endpoints.AuthorizationEndpoint +
                         "?client_id=" + Uri.EscapeDataString(Options.ClientId) +
                         "&response_type=" + Uri.EscapeDataString(scope) +
-                        "&redirect_uri=" + Uri.EscapeDataString(redirectUri);
+                        "&redirect_uri=" + Uri.EscapeDataString(redirectUri) +
+                        "&state=" + Uri.EscapeDataString(state);
 
                 Response.Redirect(authorizationEndpoint);
             }