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DataFlex

RSA Sign utf-8 Bytes of String to get Base64 RSA Signature

See more Apple Keychain Examples

Demonstrates how RSA sign the utf-8 byte representation of a string to get the signature in base64 format.

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Variant vCert
    Handle hoCert
    Handle hoSb
    Boolean iCrlfLineEnding
    Integer i
    Handle hoRsa
    String sStringToSign
    String sSigBase64
    String sTemp1
    Boolean bTemp1

    Move False To iSuccess

    // Assuming the smartcard/USB token is installed with the correct drivers from the manufacturer,
    // this code can work on multiple platforms including Windows, MacOS, Linux, and iOS.

    // Chilkat automatically detects and determines the way in which the HSM is used,
    // which can be by PKCS11, Apple Keychain, Microsoft CNG / Crypto API, or ScMinidriver.

    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End

    // Set the token/smartcard PIN prior to loading.
    Set ComSmartCardPin Of hoCert To "123456"

    // Specify the certificate by its common name.
    Get ComLoadFromSmartcard Of hoCert "cn=chilkat-rsa-2048" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComSubjectCN Of hoCert To sTemp1
    Showln "Signing with cert: " sTemp1

    // Create a string to be hashed and signed.
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSb
    If (Not(IsComObjectCreated(hoSb))) Begin
        Send CreateComObject of hoSb
    End
    Move True To iCrlfLineEnding

    For i From 0 To 10
        Get ComAppendLine Of hoSb "This is a test." iCrlfLineEnding To iSuccess
    Loop

    Get Create (RefClass(cComChilkatRsa)) To hoRsa
    If (Not(IsComObjectCreated(hoRsa))) Begin
        Send CreateComObject of hoRsa
    End

    // Use the certificate's private key for signing.
    Get pvComObject of hoCert to vCert
    Get ComSetX509Cert Of hoRsa vCert True To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoRsa To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Sign the SHA-256 hash of the utf-8 byte representation of the contents of sb
    // Return the signature in base64 format.
    Set ComEncodingMode Of hoRsa To "base64"
    Set ComCharset Of hoRsa To "utf-8"
    Get ComGetAsString Of hoSb To sStringToSign
    Get ComSignStringENC Of hoRsa sStringToSign "sha256" To sSigBase64
    Get ComLastMethodSuccess Of hoRsa To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoRsa To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "RSA signature as base64: " sSigBase64


End_Procedure