PureBasic

Duplicate openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

The in.dat file can contain text or binary data of any type. The OpenSSL command does the following:

1. Creates a SHA256 digest of the contents of the input file
2. Signs the SHA256 digest using the private key.

PureBasic

IncludeFile "CkBinData.pb"
IncludeFile "CkPrivateKey.pb"
IncludeFile "CkRsa.pb"

Procedure ChilkatExample()

    success.i = 0

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

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

    ; Load the private key from an PEM file:
    success = CkPrivateKey::ckLoadPemFile(pkey,"private.pem")
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(pkey)
        CkPrivateKey::ckDispose(pkey)
        ProcedureReturn
    EndIf

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

    ; Import the private key into the RSA component:
    success = CkRsa::ckUsePrivateKey(rsa,pkey)
    If success = 0
        Debug CkRsa::ckLastErrorText(rsa)
        CkPrivateKey::ckDispose(pkey)
        CkRsa::ckDispose(rsa)
        ProcedureReturn
    EndIf

    ; OpenSSL uses big-endian.
    CkRsa::setCkLittleEndian(rsa, 0)

    ; Load the file to be signed.
    bdFileData.i = CkBinData::ckCreate()
    If bdFileData.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkBinData::ckLoadFile(bdFileData,"in.dat")

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

    success = CkRsa::ckSignBd(rsa,bdFileData,"sha256",bdSig)
    If success = 0
        Debug CkRsa::ckLastErrorText(rsa)
        CkPrivateKey::ckDispose(pkey)
        CkRsa::ckDispose(rsa)
        CkBinData::ckDispose(bdFileData)
        CkBinData::ckDispose(bdSig)
        ProcedureReturn
    EndIf

    ; Save the binary signature to a file.
    success = CkBinData::ckWriteFile(bdSig,"signature.sig")
    If success <> 1
        Debug "Failed to write signature.sig."
        CkPrivateKey::ckDispose(pkey)
        CkRsa::ckDispose(rsa)
        CkBinData::ckDispose(bdFileData)
        CkBinData::ckDispose(bdSig)
        ProcedureReturn
    EndIf

    Debug "Success."


    CkPrivateKey::ckDispose(pkey)
    CkRsa::ckDispose(rsa)
    CkBinData::ckDispose(bdFileData)
    CkBinData::ckDispose(bdSig)


    ProcedureReturn
EndProcedure