#279 Returns detailed message for failed status code and support two-…

…tiers status code (#286)

src/extractor.ts

@@ -6,7 +6,7 @@ const dom = DOMParser;
 
 interface ExtractorField {
   key: string;
-  localPath: string[];
+  localPath: string[] | string[][];
   attributes: string[];
   index?: string[];
   attributePath?: string[];
@@ -70,12 +70,35 @@ export const loginRequestFields: ExtractorFields = [
   }
 ];
 
-export const loginResponseFields: ((asserion: any) => ExtractorFields) = assertion => [
+// support two-tiers status code
+export const loginResponseStatusFields = [
   {
-    key: 'statusCode',
+    key: 'top',
     localPath: ['Response', 'Status', 'StatusCode'],
     attributes: ['Value'],
   },
+  {
+    key: 'second',
+    localPath: ['Response', 'Status', 'StatusCode', 'StatusCode'],
+    attributes: ['Value'],
+  }
+];
+
+// support two-tiers status code
+export const logoutResponseStatusFields = [
+  {
+    key: 'top',
+    localPath: ['LogoutResponse', 'Status', 'StatusCode'],
+    attributes: ['Value']
+  },
+  {
+    key: 'second',
+    localPath: ['LogoutResponse', 'Status', 'StatusCode', 'StatusCode'],
+    attributes: ['Value'],
+  }
+];
+
+export const loginResponseFields: ((asserion: any) => ExtractorFields) = assertion => [
   {
     key: 'conditions',
     localPath: ['Assertion', 'Conditions'],
@@ -156,11 +179,6 @@ export const logoutResponseFields: ExtractorFields = [
     localPath: ['LogoutResponse'],
     attributes: ['ID', 'Destination', 'InResponseTo']
   },
-  {
-    key: 'statusCode',
-    localPath: ['LogoutResponse', 'Status', 'StatusCode'],
-    attributes: ['Value']
-  },
   {
     key: 'issuer',
     localPath: ['LogoutResponse', 'Issuer'],

src/flow.ts

@@ -7,14 +7,17 @@ import {
   loginResponseFields,
   logoutRequestFields,
   logoutResponseFields,
-  ExtractorFields
+  ExtractorFields,
+  logoutResponseStatusFields,
+  loginResponseStatusFields
 } from './extractor';
 
 import {
   BindingNamespace,
   ParserType,
   wording,
-  MessageSignatureOrder
+  MessageSignatureOrder,
+  StatusCode
 } from './urn';
 
 const bindDict = wording.binding;
@@ -65,7 +68,7 @@ async function redirectFlow(options) {
 
   const xmlString = inflateString(decodeURIComponent(content));
 
-  // validate the response xml
+  // validate the xml (remarks: login response must be gone through post flow)
   if (
     parserType === urlParams.samlRequest ||
     parserType === urlParams.logoutRequest ||
@@ -86,6 +89,9 @@ async function redirectFlow(options) {
     extract: extract(xmlString, extractorFields),
   };
 
+  // check status based on different scenarios
+  await checkStatus(xmlString, parserType);
+
   // see if signature check is required
   // only verify message signature is enough
   if (checkSignature) {
@@ -140,9 +146,12 @@ async function postFlow(options): Promise<FlowResult> {
   // validate the xml first
   await libsaml.isValidXml(samlContent);
 
-  if (parserType !== 'SAMLResponse') {
+  if (parserType !== urlParams.samlResponse) {
     extractorFields = getDefaultExtractorFields(parserType, null);
   }
+
+  // check status based on different scenarios
+  await checkStatus(samlContent, parserType);
 
   // verify the signatures (the repsonse is encrypted then signed, then verify first then decrypt)
   if (
@@ -182,7 +191,9 @@ async function postFlow(options): Promise<FlowResult> {
     extract: extract(samlContent, extractorFields),
   };
 
-  // validation part
+  /**
+   *  Validation part: validate the context of response after signature is verified and decrpyted (optional)
+   */
   const targetEntityMetadata = from.entityMeta;
   const issuer = targetEntityMetadata.getEntityID();
   const extractedProperties = parseResult.extract;
@@ -223,6 +234,32 @@ async function postFlow(options): Promise<FlowResult> {
   return Promise.resolve(parseResult);
 }
 
+function checkStatus(content: string, parserType: string): Promise<string> {
+
+  // only check response parser
+  if (parserType !== urlParams.samlResponse && parserType !== urlParams.logoutResponse) {
+    return Promise.resolve('SKIPPED');
+  }
+
+  const fields = parserType === urlParams.samlResponse
+    ? loginResponseStatusFields
+    : logoutResponseStatusFields;
+
+  const {top, second} = extract(content, fields);
+
+  // only resolve when top-tier status code is success
+  if (top === StatusCode.Success) {
+    return Promise.resolve('OK');
+  }
+
+  if (!top) {
+    throw new Error('ERR_UNDEFINED_STATUS');
+  }
+
+  // returns a detailed error for two-tier error code
+  throw new Error(`ERR_FAILED_STATUS with top tier code: ${top}, second tier code: ${second}`);
+}
+
 export function flow(options): Promise<FlowResult> {
 
   const binding = options.binding;

src/urn.ts

@@ -16,10 +16,12 @@ export enum MessageSignatureOrder {
 }
 
 export enum StatusCode {
+  // top-tier
   Success = 'urn:oasis:names:tc:SAML:2.0:status:Success',
   Requester = 'urn:oasis:names:tc:SAML:2.0:status:Requester',
   Responder = 'urn:oasis:names:tc:SAML:2.0:status:Responder',
   VersionMismatch = 'urn:oasis:names:tc:SAML:2.0:status:VersionMismatch',
+  // second-tier to provide more information
   AuthFailed = 'urn:oasis:names:tc:SAML:2.0:status:AuthnFailed',
   InvalidAttrNameOrValue = 'urn:oasis:names:tc:SAML:2.0:status:InvalidAttrNameOrValue',
   InvalidNameIDPolicy = 'urn:oasis:names:tc:SAML:2.0:status:InvalidNameIDPolicy',

test/flow.ts

@@ -651,3 +651,12 @@ test('should reject signature wrapped response - case 2', async t => {
     t.is(e.message, 'ERR_POTENTIAL_WRAPPING_ATTACK');
   }
 });
+
+test('should throw two-tiers code error when the response does not return success status', async t => {
+  const failedResponse: string = String(readFileSync('./test/misc/failed_response.xml'));
+  try {
+    const _result = await sp.parseLoginResponse(idpNoEncrypt, 'post', { body: { SAMLResponse: utility.base64Encode(failedResponse) } });
+  } catch (e) {
+    t.is(e.message, 'ERR_FAILED_STATUS with top tier code: urn:oasis:names:tc:SAML:2.0:status:Requester, second tier code: urn:oasis:names:tc:SAML:2.0:status:InvalidNameIDPolicy');
+  }
+});

test/misc/failed_response.xml

@@ -0,0 +1 @@
+<samlp:Response xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion" ID="_8e8dc5f69a98cc4c1ff3427e5ce34606fd672f91e6" Version="2.0" IssueInstant="2014-07-17T01:01:48Z" Destination="http://sp.example.com/demo1/index.php?acs" InResponseTo="_41e758fee373d51639552c4b040b1090e97f6685"><saml:Issuer>https://idp.example.com/metadata</saml:Issuer><samlp:Status><samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Requester"><samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:InvalidNameIDPolicy"/></samlp:StatusCode></samlp:Status></samlp:Response>