Xbase++ Requires Chilkat v11.0.0+

RSA Encrypt Hash using SHA256 hash function and SHA1 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.

Xbase++

LOCAL nSuccess
LOCAL oPubkey
LOCAL oSbPem
LOCAL nBCrlf
LOCAL cOriginalData
LOCAL oCrypt
LOCAL cHashBase64
LOCAL oRsa
LOCAL nBUsePrivateKey
LOCAL cEncryptedStr

nSuccess := 0

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

oPubkey := CreateObject("Chilkat.PublicKey")

oSbPem := CreateObject("Chilkat.StringBuilder")
nBCrlf := 1
oSbPem:AppendLine("-----BEGIN PUBLIC KEY-----", nBCrlf)
oSbPem:AppendLine("MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF", nBCrlf)
oSbPem:AppendLine("3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA", nBCrlf)
oSbPem:AppendLine("04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s", nBCrlf)
oSbPem:AppendLine("Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF", nBCrlf)
oSbPem:AppendLine("wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE", nBCrlf)
oSbPem:AppendLine("f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W", nBCrlf)
oSbPem:AppendLine("SwIDAQAB", nBCrlf)
oSbPem:AppendLine("-----END PUBLIC KEY-----", nBCrlf)

//  Load the public key object from the PEM. 
nSuccess := oPubkey:LoadFromString(oSbPem:GetAsString())
IF (nSuccess == 0)
    ? oPubkey:LastErrorText
    oPubkey:destroy()
    oSbPem:destroy()
    RETURN
ENDIF

cOriginalData := "This is the original data to be SHA-256 hashed and RSA encrypted."

//  First we SHA-256 hash the original data to get the hash in base64 format:
oCrypt := CreateObject("Chilkat.Crypt2")
oCrypt:HashAlgorithm := "SHA-256"
oCrypt:EncodingMode := "base64"
cHashBase64 := oCrypt:HashStringENC(cOriginalData)

//  Setup RSA to use OAEP padding with SHA-1 for the mask function.
oRsa := CreateObject("Chilkat.Rsa")
oRsa:PkcsPadding := 0
oRsa:OaepHash := "SHA256"
oRsa:UsePublicKey(oPubkey)
oRsa:EncodingMode := "base64"

//  We can provide a binary encoding mode, such as "base64", "hex", "base64url", etc.
//  for the Charset property.   The Charset property was previously limited to character encodings, such as
//  "utf-8", "iso-8859-1", etc.  If a binary encoding is used, then the string passed in is decoded to the binary
//  bytes as indicated.  (If an actual charset, such as "utf-8" is used, then the input string is converted to the
//  byte representation of the charset, and then encrypted.)

//  Given that a hash is composed of non-text binary bytes, we'll set the Charset property equal to "base64" 
//  (because we have the base64 hash from above).
oRsa:Charset := "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.
nBUsePrivateKey := 0
cEncryptedStr := oRsa:EncryptStringENC(cHashBase64, nBUsePrivateKey)
IF (oRsa:LastMethodSuccess == 0)
    ? oRsa:LastErrorText
    oPubkey:destroy()
    oSbPem:destroy()
    oCrypt:destroy()
    oRsa:destroy()
    RETURN
ENDIF

? "Base64 RSA encrypted output: " + cEncryptedStr

oPubkey:destroy()
oSbPem:destroy()
oCrypt:destroy()
oRsa:destroy()