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I want to integrate the Aadhaar Card Authentication API for Aadhaar number Verification in PHP. I tried this and wrote code for API access.

I am getting this error. Please help me in generating the XML encryption field data below in PHP?

   <Auth uid="" tid="" ac="" sa="" ver="" txn="" lk="">
        <Uses pi="" pa="" pfa="" bio="" bt="" pin="" otp=""/>
        <Tkn type="" value=""/>
        <Meta udc="" fdc="" idc="" pip="" lot=”G|P” lov=""/>
        <Skey ci="" ki="">encrypted and encoded session key</Skey>
        <Data type=”X|P”>encrypted PID block</Data>
        <Hmac>SHA-256 Hash of Pid block, encrypted and then encoded</Hmac>
        <Signature>Digital signature of AUA</Signature>
    </Auth>