Classic ASP Requires Chilkat v11.0.0+
Duo Auth API - Async Auth

If you enable async, then your application will be able to retrieve real-time status updates from the authentication process, rather than receiving no information until the process is complete.
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Classic ASP
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<%
success = 0

'  This example assumes the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.

integrationKey = "DIMS3V5QDVG9J9ABRXC4"
secretKey = "HWVQ46nubLBxhnRlKddTltWIi3hL0fIQF2qTvLab"

set http = Server.CreateObject("Chilkat.Http")

http.Accept = "application/json"

'  Use your own hostname here:
url = "https://api-a03782e1.duosecurity.com/auth/v2/auth"

'  This example requires Chilkat v9.5.0.89 or greater because Chilkat will automatically
'  generate and send the HMAC signature for the requires based on the integration key and secret key.
http.Login = integrationKey
http.Password = secretKey

set req = Server.CreateObject("Chilkat.HttpRequest")
req.AddParam "username","matt"
req.AddParam "factor","push"
'  The device ID can be obtained from the preauth response.  See Duo Preauth Example
req.AddParam "device","DP6GYVTQ5NK82BMR851F"
'  Add the async param to get an immediate response, then periodically check for updates to find out when the MFA authentication completes for fails.
req.AddParam "async","1"

req.HttpVerb = "POST"
req.ContentType = "application/x-www-form-urlencoded"

set resp = Server.CreateObject("Chilkat.HttpResponse")
success = http.HttpReq(url,req,resp)
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( http.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "status code = " & resp.StatusCode) & "</pre>"

set json = Server.CreateObject("Chilkat.JsonObject")
success = json.Load(resp.BodyStr)
json.EmitCompact = 0
Response.Write "<pre>" & Server.HTMLEncode( json.Emit()) & "</pre>"

If (resp.StatusCode <> 200) Then
    Response.End
End If

'  Sample successful output:

'  status code = 200

'  {
'    "stat": "OK",
'    "response": {
'      "txid": "45f7c92b-f45f-4862-8545-e0f58e78075a"
'    }
'  }

txid = json.StringOf("response.txid")

'  Use your own hostname here:
set sbUrl = Server.CreateObject("Chilkat.StringBuilder")
success = sbUrl.Append("https://api-a03782e1.duosecurity.com/auth/v2/auth_status?txid=")
success = sbUrl.Append(txid)
url = sbUrl.GetAsString()

Response.Write "<pre>" & Server.HTMLEncode( "Auth status URL: " & url) & "</pre>"

set sbResult = Server.CreateObject("Chilkat.StringBuilder")

'  Wait for a response...
i = 0
maxWaitIterations = 100
Do While i < maxWaitIterations
    '  Wait 3 seconds.
    http.SleepMs 3000

    Response.Write "<pre>" & Server.HTMLEncode( "Polling...") & "</pre>"

    success = http.HttpNoBody("GET",url,resp)
    If (success = 0) Then
        Response.Write "<pre>" & Server.HTMLEncode( http.LastErrorText) & "</pre>"
        Response.End
    End If

    If (resp.StatusCode <> 200) Then
        Response.Write "<pre>" & Server.HTMLEncode( "error status code = " & resp.StatusCode) & "</pre>"
        Response.Write "<pre>" & Server.HTMLEncode( resp.BodyStr) & "</pre>"
        Response.Write "<pre>" & Server.HTMLEncode( "Failed.") & "</pre>"
        Response.End
    End If

    '  Sample response:

    '  	{
    '  	  "stat": "OK",
    '  	  "response": {
    '  	    "result": "waiting",
    '  	    "status": "pushed",
    '  	    "status_msg": "Pushed a login request to your phone..."
    '  	  }
    '  	}

    success = json.Load(resp.BodyStr)

    '  The responseResult can be "allow", "deny", or "waiting"
    sbResult.Clear 
    success = json.StringOfSb("response.result",sbResult)
    responseStatus = json.StringOf("response.status")
    responseStatus_msg = json.StringOf("response.status_msg")

    Response.Write "<pre>" & Server.HTMLEncode( sbResult.GetAsString()) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( responseStatus) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( responseStatus_msg) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( "") & "</pre>"

    If (sbResult.ContentsEqual("waiting",1) = 1) Then
        i = i + 1
    Else
        '  Force loop exit..
        i = maxWaitIterations
    End If

Loop

Response.Write "<pre>" & Server.HTMLEncode( "Finished.") & "</pre>"

%>
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