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

The /preauth endpoint determines whether a user is authorized to log in, and (if so) returns the user's available authentication factors.
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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/preauth"

http.Login = integrationKey
http.Password = secretKey

set req = Server.CreateObject("Chilkat.HttpRequest")
req.AddParam "username","matt"

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>"

'  Sample successful output:

'  status code = 200

'  {
'    "response": {
'      "devices": [
'        {
'          "capabilities": [
'            "auto",
'            "push",
'            "sms",
'            "mobile_otp"
'          ],
'          "device": "DP6GYVTQ5NK82BMR851F",
'          "display_name": "iOS (XXX-XXX-1871)",
'          "name": "",
'          "number": "XXX-XXX-1871",
'          "type": "phone"
'        }
'      ],
'      "result": "auth",
'      "status_msg": "Account is active"
'    },
'    "stat": "OK"
'  }

'  Sample code to parse the above JSON response..

'  Use this online tool to generate parsing code from sample JSON: 
'  Generate Parsing Code from JSON

responseResult = json.StringOf("response.result")
responseStatus_msg = json.StringOf("response.status_msg")
stat = json.StringOf("stat")
i = 0
count_i = json.SizeOfArray("response.devices")
Do While i < count_i
    json.I = i
    device = json.StringOf("response.devices[i].device")
    display_name = json.StringOf("response.devices[i].display_name")
    name = json.StringOf("response.devices[i].name")
    number = json.StringOf("response.devices[i].number")
    v_type = json.StringOf("response.devices[i].type")
    j = 0
    count_j = json.SizeOfArray("response.devices[i].capabilities")
    Do While j < count_j
        json.J = j
        strVal = json.StringOf("response.devices[i].capabilities[j]")
        j = j + 1
    Loop
    i = i + 1
Loop

%>
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