Implement authentication support for wxWebRequest under Mac

Add wxWebAuthChallengeURLSession and use the appropriate delegate
callback to create it.

include/wx/osx/private/webrequest_urlsession.h

@@ -14,6 +14,7 @@
 
 #include "wx/private/webrequest.h"
 
+DECLARE_WXCOCOA_OBJC_CLASS(NSURLCredential);
 DECLARE_WXCOCOA_OBJC_CLASS(NSURLSession);
 DECLARE_WXCOCOA_OBJC_CLASS(NSURLSessionTask);
 DECLARE_WXCOCOA_OBJC_CLASS(wxWebSessionDelegate);
@@ -22,6 +23,29 @@ class wxWebSessionURLSession;
 class wxWebRequestURLSession;
 class wxWebResponseURLSession;
 
+class wxWebAuthChallengeURLSession : public wxWebAuthChallengeImpl
+{
+public:
+    wxWebAuthChallengeURLSession(wxWebAuthChallenge::Source source,
+                                 wxWebRequestURLSession& request)
+        : wxWebAuthChallengeImpl(source),
+          m_request(request)
+    {
+    }
+
+    ~wxWebAuthChallengeURLSession();
+
+    void SetCredentials(const wxWebCredentials& cred) wxOVERRIDE;
+
+    WX_NSURLCredential GetURLCredential() const { return m_cred; }
+
+private:
+    wxWebRequestURLSession& m_request;
+    WX_NSURLCredential m_cred = NULL;
+
+    wxDECLARE_NO_COPY_CLASS(wxWebAuthChallengeURLSession);
+};
+
 class wxWebResponseURLSession : public wxWebResponseImpl
 {
 public:
@@ -67,7 +91,8 @@ public:
     wxWebResponseImplPtr GetResponse() const wxOVERRIDE
         { return m_response; }
 
-    wxWebAuthChallengeImplPtr GetAuthChallenge() const wxOVERRIDE;
+    wxWebAuthChallengeImplPtr GetAuthChallenge() const wxOVERRIDE
+        { return m_authChallenge; }
 
     wxFileOffset GetBytesSent() const wxOVERRIDE;
 
@@ -79,14 +104,22 @@ public:
 
     void HandleCompletion();
 
+    void HandleChallenge(wxWebAuthChallengeURLSession* challenge);
+
+    void OnSetCredentials(const wxWebCredentials& cred);
+
     wxWebResponseURLSession* GetResponseImplPtr() const
         { return m_response.get(); }
 
+    wxWebAuthChallengeURLSession* GetAuthChallengeImplPtr() const
+        { return m_authChallenge.get(); }
+
 private:
     wxWebSessionURLSession& m_sessionImpl;
     wxString m_url;
     WX_NSURLSessionTask m_task;
     wxObjectDataPtr<wxWebResponseURLSession> m_response;
+    wxObjectDataPtr<wxWebAuthChallengeURLSession> m_authChallenge;
 
     wxDECLARE_NO_COPY_CLASS(wxWebRequestURLSession);
 };

src/osx/webrequest_urlsession.mm

@@ -97,6 +97,60 @@
     [m_requests removeObjectForKey:task];
 }
 
+- (void)URLSession:(NSURLSession *)session
+        task:(NSURLSessionTask *)task
+        didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge
+        completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition, NSURLCredential *credential))completionHandler
+{
+    wxUnusedVar(session);
+
+    wxWebRequestURLSession* request = [self requestForTask:task];
+    wxCHECK_RET( request, "received authentication challenge for an unknown task" );
+
+    NSURLProtectionSpace* const space = [challenge protectionSpace];
+
+    wxLogTrace(wxTRACE_WEBREQUEST, "Request %p: didReceiveChallenge for %s",
+               request,
+               wxCFStringRefFromGet([space description]).AsString());
+
+    // We need to distinguish between session-wide and task-specific
+    // authentication challenges, we're only really interested in the latter
+    // ones here (but apparently there is no way to get just them, even though
+    // the documentation seems to imply that session-wide challenges shouldn't
+    // be sent to this task-specific delegate -- but they're, at least under
+    // 10.14).
+    const auto authMethod = space.authenticationMethod;
+    if ( authMethod == NSURLAuthenticationMethodHTTPBasic ||
+            authMethod == NSURLAuthenticationMethodHTTPDigest )
+    {
+        if ( auto* const authChallenge = request->GetAuthChallengeImplPtr() )
+        {
+            // We're going to get called until we don't provide the correct
+            // credentials, so don't use them again (and again, and again...)
+            // if we had already used them unsuccessfully.
+            if ( !challenge.previousFailureCount )
+            {
+                wxLogTrace(wxTRACE_WEBREQUEST, "Request %p: using credentials", request);
+
+                completionHandler(NSURLSessionAuthChallengeUseCredential,
+                                  authChallenge->GetURLCredential());
+
+                return;
+            }
+
+            wxLogTrace(wxTRACE_WEBREQUEST, "Request %p: not using failing credentials again", request);
+        }
+
+        request->HandleChallenge(new wxWebAuthChallengeURLSession(
+            [space isProxy] ? wxWebAuthChallenge::Source_Proxy
+                            : wxWebAuthChallenge::Source_Server,
+            *request
+        ));
+    }
+
+    completionHandler(NSURLSessionAuthChallengePerformDefaultHandling, nil);
+}
+
 @end
 
 //
@@ -170,14 +224,22 @@ void wxWebRequestURLSession::Cancel()
 
 void wxWebRequestURLSession::HandleCompletion()
 {
+    switch ( m_response->GetStatus() )
+    {
+        case 401:
+        case 407:
+            SetState(wxWebRequest::State_Unauthorized, m_response->GetStatusText());
+            break;
+
+        default:
             if ( CheckServerStatus() )
                 SetState(wxWebRequest::State_Completed);
+    }
 }
 
-wxWebAuthChallengeImplPtr wxWebRequestURLSession::GetAuthChallenge() const
+void wxWebRequestURLSession::HandleChallenge(wxWebAuthChallengeURLSession* challenge)
 {
-    wxFAIL_MSG("not implemented");
-    return wxWebAuthChallengeImplPtr();
+    m_authChallenge.reset(challenge);
 }
 
 wxFileOffset wxWebRequestURLSession::GetBytesSent() const
@@ -200,6 +262,33 @@ wxFileOffset wxWebRequestURLSession::GetBytesExpectedToReceive() const
     return m_task.countOfBytesExpectedToReceive;
 }
 
+//
+// wxWebAuthChallengeURLSession
+//
+
+wxWebAuthChallengeURLSession::~wxWebAuthChallengeURLSession()
+{
+    [m_cred release];
+}
+
+void wxWebAuthChallengeURLSession::SetCredentials(const wxWebCredentials& cred)
+{
+    wxLogTrace(wxTRACE_WEBREQUEST, "Request %p: setting credentials", &m_request);
+
+    [m_cred release];
+
+    m_cred = [NSURLCredential
+        credentialWithUser:wxCFStringRef(cred.GetUser()).AsNSString()
+        password:wxCFStringRef(wxSecretString(cred.GetPassword())).AsNSString()
+        persistence:NSURLCredentialPersistenceNone
+    ];
+
+    [m_cred retain];
+
+    m_request.Start();
+}
+
+
 //
 // wxWebResponseURLSession
 //

tests/net/webrequest.cpp

@@ -42,12 +42,6 @@ public:
         dataSize = 0;
     }
 
-    static bool UsingNSURLSession()
-    {
-        return wxWebSession::GetDefault().GetLibraryVersionInfo().GetName()
-                == "URLSession";
-    }
-
     // All tests should call this function first and skip the test entirely if
     // it returns false, as this indicates that web requests tests are disabled.
     bool InitBaseURL()
@@ -240,12 +234,6 @@ TEST_CASE_METHOD(RequestFixture,
     if ( !InitBaseURL() )
         return;
 
-    if ( UsingNSURLSession() )
-    {
-        WARN("NSURLSession backend doesn't support authentication, skipping.");
-        return;
-    }
-
     Create("/basic-auth/wxtest/wxwidgets");
     Run(wxWebRequest::State_Unauthorized, 401);
     REQUIRE( request.GetAuthChallenge().IsOk() );
@@ -273,12 +261,6 @@ TEST_CASE_METHOD(RequestFixture,
     if ( !InitBaseURL() )
         return;
 
-    if ( UsingNSURLSession() )
-    {
-        WARN("NSURLSession backend doesn't support authentication, skipping.");
-        return;
-    }
-
     Create("/digest-auth/auth/wxtest/wxwidgets");
     Run(wxWebRequest::State_Unauthorized, 401);
     REQUIRE( request.GetAuthChallenge().IsOk() );