Xbase++

RSAES-OAEP Encrypt String with AES-128 Content Encryption and SHA256

See more Encryption Examples

Encrypts a string using RSAES-OAEP with SHA256 and AES-128 content encryption to produce PKCS7 output (base64 encoded).

Note: This example requires Chilkat v9.5.0.67 or greater.

Xbase++

LOCAL nSuccess
LOCAL oSb
LOCAL i
LOCAL oCert
LOCAL oCrypt
LOCAL cBase64Pkcs7

nSuccess := 0

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

//  First build a string to be encrypted
oSb := CreateObject("Chilkat.StringBuilder")
i := 1
DO WHILE i < 25
    oSb:AppendInt(i)
    oSb:Append(" the quick brown fox jumped over the lazy dog." + Chr(13) + Chr(10))
    i := i + 1
ENDDO

? oSb:GetAsString()

//  The string to be encrypted looks like this:

//  1 the quick brown fox jumped over the lazy dog.
//  2 the quick brown fox jumped over the lazy dog.
//  3 the quick brown fox jumped over the lazy dog.
//  4 the quick brown fox jumped over the lazy dog.
//  5 the quick brown fox jumped over the lazy dog.
//  6 the quick brown fox jumped over the lazy dog.
//  ...

//  Load a digital certificate. 
//  We don't need the private key for encryption.
//  Only the public key is needed (which is included in a certificate).
oCert := CreateObject("Chilkat.Cert")
nSuccess := oCert:LoadFromFile("qa_data/rsaes-oaep/cert.pem")
IF (nSuccess != 1)
    ? oCert:LastErrorText
    oSb:destroy()
    oCert:destroy()
    RETURN
ENDIF

oCrypt := CreateObject("Chilkat.Crypt2")

//  Tell the crypt object to use the certificate.
oCrypt:SetEncryptCert(oCert)

//  Indicate that we want PKI encryption (i.e. public-key infrastructure)
//  to produce a CMS message (Cryptographic Message Syntax/PKCS7),
//  that is be created with RSAES-OAEP padding, SHA256, and AES-128 for the
//  bulk encryption.
oCrypt:CryptAlgorithm := "pki"
oCrypt:Pkcs7CryptAlg := "aes"
oCrypt:KeyLength := 128
oCrypt:OaepHash := "sha256"
oCrypt:OaepPadding := 1

//  Also, don't forget to be specific about the character encoding (byte representation) of the
//  string to be encrypted.
oCrypt:Charset := "utf-8"

//  Now indicate that the PKCS7 output is to be returned in the base64 encoding.
oCrypt:EncodingMode := "base64"

cBase64Pkcs7 := oCrypt:EncryptStringENC(oSb:GetAsString())
IF (oCrypt:LastMethodSuccess != 1)
    ? oCrypt:LastErrorText
    oSb:destroy()
    oCert:destroy()
    oCrypt:destroy()
    RETURN
ENDIF

//  Show the output
? cBase64Pkcs7

//  This base64 can be copy-and-pasted into the form at http://lapo.it/asn1js/
//  to verify that all the chosen algorithms were indeed used.

? "OK."

oSb:destroy()
oCert:destroy()
oCrypt:destroy()