OWIN: webapi call returning 401 unauthoried Error in Azure

Question

I have created two applications one for front end(created using AngularJs and Asp.Net MVC) and for backend I used web Api application.

I am trying to secure my application with forms authentication in front End and implemented basic forms authentication in back End.

When I tested locally in IIS it works fine.But when I hosted my application in Azure, API call with authentication attribute returns with 401 unauthorized error.

response Header:

 Access-Control-Allow-Origin:*
    Cache-Control:no-cache
    Content-Length:0
    Date:Wed, 05 Oct 2016 11:08:30 GMT
    Expires:-1
    Pragma:no-cache
    Server:Microsoft-IIS/8.0
    Set-Cookie:ARRAffinity=925cd503f9e5771e9ad651c59baa4a1f678d93cac8b9da4dc9bcb64892ac8710;Path=/;Domain=FrontEnd.azurewebsites.net
    WWW-Authenticate:Basic realm="Backend.azurewebsites.net"
    X-AspNet-Version:4.0.30319
    X-Powered-By:ASP.NET

Request Header;

Accept:application/json, text/plain, */*
Accept-Encoding:gzip, deflate, sdch, br
Accept-Language:en-US,en;q=0.8
Cache-Control:no-cache
Connection:keep-alive
Host:backend.azurewebsites.net
Origin:http://FrontEnd.azurewebsites.net
Pragma:no-cache
Referer:http://FrontEnd.azurewebsites.net/
Token:null
User-Agent:Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36

But in local along with request header

    Authorization: Basic dmlzaG53guFua2FyLnNha3Roadh4bEBnbWFpbC5jb206MTIzMTIz
   Cookie: __RequestVerificationToken_L3Nfg4dwc3Bh0=YGwlXkckjhg6xTESkI-lN9sNtDVsfefshsrvGWPKekmv_GLZ0Rq8eA5P8Z7sdf4trwbPX4WymcGJJrLamQLMe2Vf2D2fVUg4qJptOvcsCWg1; ASP.NET_SessionId=gk4s1rlsfg5gfeafo3455dkr; .ASPXAUTH=C8113FD23FC4902dsfrsdf5FB3399BA121703F41F9A57AEA50667F2AD4FC02F3D3955215A91F6A3A2EA4287202522380435A93D8BE78D45E6D24FB7E05F64653AE06E0026DEB2911343591563F70EE8EE76338F07CBABE6EA4B95359F3C31sdf9C999sdf2864849gfdB916A06gfds29E3C8D01D2371807E98335000D4D14B391CCE3zxcd49DB77696F4BB77E4434

is passed

Authorization and Cookie parameter is not get added in request from azure frontEND app with forms authentication.

I Looked into authentication/authorization configuration of my backend app in azure it sets off.can any body know what is the issue or what I need to configure in azure portal.Thanks in advance.

Answer 1

This issue is due to cors you can solve this by adding in your request,

 $http({
  ....
  headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
  withCredentials: true,
  })

WEB.Config of web API

 <system.webServer>
        <validation validateIntegratedModeConfiguration="false" />
            <handlers>
                <remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" />
                <remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" />
                <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
                <remove name="OPTIONSVerbHandler" />
                <remove name="TRACEVerbHandler" />

                <add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
                <add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0" />
                <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
            </handlers>


            <httpProtocol>
                <customHeaders>
                    <add name="Access-Control-Allow-Origin" value="**FrontEnd URL**" />
                    <add name="Access-Control-Allow-Headers" value="Origin, X-Requested-With, Content-Type, Accept, Cache-Control" />
                    <add name="Access-Control-Allow-Credentials" value="true" />
                    <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
                </customHeaders>
            </httpProtocol>
      </system.webServer>

you also refer this URl as well: https://www.asp.net/web-api/overview/security/enabling-cross-origin-requests-in-web-api

Answer 2

This is probably because they are no longer hosted on the same machine (depending on your Azure setup). I've had a similar problem with machineKey myself.

Follow the instructions in the following URL to match up the settings between the applications and you should be fine:

https://msdn.microsoft.com/en-us/library/eb0zx8fc.aspx

EDIT: With Access-Control-Allow-Origin:* in the response header it is probably not a normal CORS problem, although machineKey and CORS problems often come together. If the machineKey fix does not work, check how you are handling CORS pre-flight checks. See my answer here.