Xbase++

Decrypt S/MIME using a Certificate with Private Key Access

Loads a CMS/PKCS #7 encrypted S/MIME message and decrypts it back to the original MIME content.

DecryptUsingCert takes a single certificate that already has access to its associated private key, for example a certificate loaded from a PFX.

The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background. A public-only certificate is insufficient for decryption. The certificate passed to DecryptUsingCert must be linked to its private key, as happens when it is loaded from a PFX/P12 file.

Chilkat Xbase++ Downloads

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Xbase++

LOCAL nSuccess
LOCAL oMime
LOCAL cPfxPassword
LOCAL oCert
LOCAL cBody

nSuccess := 0

oMime := CreateObject("Chilkat.Mime")
nSuccess := oMime:LoadMimeFile("qa_data/encrypted.eml")
IF (nSuccess == 0)
    ? oMime:LastErrorText
    oMime:destroy()
    RETURN
ENDIF

//  Decrypt using a certificate that already provides access to its private key (for example loaded
//  from a PFX).  The only argument is the certificate.
cPfxPassword := "myPfxPassword"
oCert := CreateObject("Chilkat.Cert")
nSuccess := oCert:LoadPfxFile("qa_data/recipient.pfx", cPfxPassword)
IF (nSuccess == 0)
    ? oCert:LastErrorText
    oMime:destroy()
    oCert:destroy()
    RETURN
ENDIF

nSuccess := oMime:DecryptUsingCert(oCert)
IF (nSuccess == 0)
    ? oMime:LastErrorText
    oMime:destroy()
    oCert:destroy()
    RETURN
ENDIF

cBody := oMime:GetBodyDecoded()
IF (oMime:LastMethodSuccess == 0)
    ? oMime:LastErrorText
    oMime:destroy()
    oCert:destroy()
    RETURN
ENDIF

? cBody

oMime:destroy()
oCert:destroy()