PureBasic

RSA OAEP Padding

See more RSA Examples

Demonstrates how to use OAEP padding with the RSA encryption algorithm. More information about OAEP Padding. PureBasic

IncludeFile "CkPublicKey.pb"
IncludeFile "CkRsa.pb"

Procedure ChilkatExample()

    success.i = 0

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

    rsa.i = CkRsa::ckCreate()
    If rsa.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; RSA public key in XML format:
    pubKeyXml.s = "<RSAPublicKey><Modulus>of3im3mRgd2NLXIGoK6uYLg6jj0Ug2b42rnqa5Tbwz2ieFqMJqt+++x2oqLYGurlz49nt+7/785g3XYWqoka4u9c9zul6YubIjnBM72dQy7rEkEfbUxgjcxqXyjZFx+FpaxFUecLu688XEu+9UA42VKiCgcl+E7TrqnfeeYpNXc=</Modulus><Exponent>AQAB</Exponent></RSAPublicKey>"

    pubKey.i = CkPublicKey::ckCreate()
    If pubKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPublicKey::ckLoadFromString(pubKey,pubKeyXml)
    If success = 0
        Debug CkPublicKey::ckLastErrorText(pubKey)
        CkRsa::ckDispose(rsa)
        CkPublicKey::ckDispose(pubKey)
        ProcedureReturn
    EndIf

    success = CkRsa::ckUsePublicKey(rsa,pubKey)
    If success = 0
        Debug CkRsa::ckLastErrorText(rsa)
        CkRsa::ckDispose(rsa)
        CkPublicKey::ckDispose(pubKey)
        ProcedureReturn
    EndIf

    ; To use Optimal Asymmetric Encryption Padding (OAEP) padding,
    ; simply set the PkcsPadding property to 0
    CkRsa::setCkPkcsPadding(rsa, 0)

    ; Encrypt a string and return the encrypted data base64-encoded:
    CkRsa::setCkEncodingMode(rsa, "base64")

    plainText.s = "RSA Encryption should be easy."

    usePrivateKey.i = 0
    encryptedStr.s = CkRsa::ckEncryptStringENC(rsa,plainText,usePrivateKey)
    Debug encryptedStr


    CkRsa::ckDispose(rsa)
    CkPublicKey::ckDispose(pubKey)


    ProcedureReturn
EndProcedure