(PureBasic) Send Encrypted Email with a Selected Algorithm (AES, 3DES, etc.)

Sends an encrypted email using the recipient's digital certificate from a .cer file, and chooses 3DES for the encryption algorithm. (It is also possible to send AES encrypted email w/ 128-bit, 192-bit, or 256-bit encryption simply by setting the Pkcs7CryptAlg and Pkcs7KeyLength properties.)

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkCert.pb"
IncludeFile "CkEmail.pb"
IncludeFile "CkMailMan.pb"

Procedure ChilkatExample()

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

    ; The mailman object is used for sending and receiving email.
    mailman.i = CkMailMan::ckCreate()
    If mailman.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Set the SMTP server.
    CkMailMan::setCkSmtpHost(mailman, "smtp.mymailserver.com")

    ; Load the .cer file into a certificate object.
    ; When sending S/MIME encrypted email, it is the recipient's
    ; certificate that is used for encryption.  Only the public key
    ; is needed to encrypt.  The recipient is the only
    ; one possessing the private key, and therefore is the only
    ; one able to decrypt.
    cert.i = CkCert::ckCreate()
    If cert.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success.i = CkCert::ckLoadFromFile(cert,"cknotes.cer")
    If success <> 1
        Debug CkCert::ckLastErrorText(cert)
        CkMailMan::ckDispose(mailman)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; Create a new email object
    email.i = CkEmail::ckCreate()
    If email.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkEmail::setCkSubject(email, "This email is encrypted")
    CkEmail::setCkBody(email, "This is a digitally encrypted mail")
    CkEmail::setCkFrom(email, "Chilkat Support <support@chilkatsoft.com>")
    success = CkEmail::ckAddTo(email,"Chilkat Blog","admin@cknotes.com")

    ; Indicate that the email is to be sent encrypted.
    CkEmail::setCkSendEncrypted(email, 1)

    ; Specify the certificate to be used for encryption.
    success = CkEmail::ckSetEncryptCert(email,cert)

    ; If desired, specify the encryption algorithm to be used.
    ; The Pkcs7CryptAlg property can be set to "aes", "des", "3des", or "rc2"
    CkEmail::setCkPkcs7CryptAlg(email, "3des")

    ; If desired, set the key length (in bits) for the encryption algorithm:
    ; The possible values allowed depend on the Pkcs7CryptAlg property. 
    ; For "aes", the key length may be 128, 192, or 256. 
    ; For "3des" the key length must be 192. 
    ; For "des" the key length must be 40. 
    ; For "rc2" the key length can be 40, 56, 64, or 128.
    CkEmail::setCkPkcs7KeyLength(email, 192)

    success = CkMailMan::ckSendEmail(mailman,email)
    If success <> 1
        Debug CkMailMan::ckLastErrorText(mailman)
    Else
        Debug "Mail Sent!"
    EndIf



    CkMailMan::ckDispose(mailman)
    CkCert::ckDispose(cert)
    CkEmail::ckDispose(email)


    ProcedureReturn
EndProcedure