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DataFlex Requires Chilkat v11.0.0+

RSA Encrypt with SHA-256 hash function and SHA-256 mask function

See more RSA Examples

How can this Javascript be duplicated using Chilkat?
function a(e, t) {
                var r = s.pki.publicKeyFromPem(e)
                  , n = r.encrypt(t, "RSA-OAEP", {
                    md: s.md.sha256.create(),
                    mgf1: {
                        md: s.md.sha1.create()
                    }
                });
                return s.util.encode64(n)
            }

Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens, even using the same data and key, the result will be different -- but still valid. One should not expect to get the same output.

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Variant vPubkey
    Handle hoPubkey
    Handle hoSbPem
    Boolean iBCrlf
    String sOriginalData
    Handle hoCrypt
    Variant hoHashBytes
    Handle hoRsa
    Boolean iBUsePrivateKey
    String sEncryptedStr
    String sTemp1
    Boolean bTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatPublicKey)) To hoPubkey
    If (Not(IsComObjectCreated(hoPubkey))) Begin
        Send CreateComObject of hoPubkey
    End

    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbPem
    If (Not(IsComObjectCreated(hoSbPem))) Begin
        Send CreateComObject of hoSbPem
    End
    Move True To iBCrlf
    Get ComAppendLine Of hoSbPem "-----BEGIN PUBLIC KEY-----" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "SwIDAQAB" iBCrlf To iSuccess
    Get ComAppendLine Of hoSbPem "-----END PUBLIC KEY-----" iBCrlf To iSuccess

    //  Load the public key object from the PEM. 
    Get ComGetAsString Of hoSbPem To sTemp1
    Get ComLoadFromString Of hoPubkey sTemp1 To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPubkey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Move "This is the original data to be SHA-256 hashed and RSA encrypted." To sOriginalData

    //  First we SHA-256 hash the original data.
    Get Create (RefClass(cComChilkatCrypt2)) To hoCrypt
    If (Not(IsComObjectCreated(hoCrypt))) Begin
        Send CreateComObject of hoCrypt
    End
    Set ComHashAlgorithm Of hoCrypt To "SHA-256"

    Get ComHashString Of hoCrypt sOriginalData To hoHashBytes

    //  Now to RSA encrypt using OAEP padding with SHA-256 for the mask function.
    Get Create (RefClass(cComChilkatRsa)) To hoRsa
    If (Not(IsComObjectCreated(hoRsa))) Begin
        Send CreateComObject of hoRsa
    End
    Set ComPkcsPadding Of hoRsa To False
    Set ComOaepHash Of hoRsa To "SHA256"
    Get pvComObject of hoPubkey to vPubkey
    Get ComUsePublicKey Of hoRsa vPubkey To iSuccess
    Set ComEncodingMode Of hoRsa To "base64"

    //  Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens,
    //  even using the same data and key, the result will be different --  but still valid.  One should not expect
    //  to get the same output.
    Move False To iBUsePrivateKey
    Get ComEncryptBytesENC Of hoRsa vHashBytes iBUsePrivateKey To sEncryptedStr
    Get ComLastMethodSuccess Of hoRsa To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoRsa To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "Base64 RSA encrypted output: " sEncryptedStr


End_Procedure