Sign a File to Create a .p7m File

Visual FoxPro example to sign a file creating a .p7m file as output. The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

Download Chilkat Crypt ActiveX

LOCAL loCrypt
LOCAL lnSuccess
LOCAL loCcs
LOCAL loCertStore
LOCAL loCert

loCrypt = CreateObject('Chilkat.Crypt2')

*  Any string argument automatically begins the 30-day trial.

lnSuccess = loCrypt.UnlockComponent("30-day trial")
IF (lnSuccess <> 1) THEN
    =MESSAGEBOX("Crypt component unlock failed")
    QUIT
ENDIF

*  Find our digital certificate from the Current User certificate store.
loCcs = CreateObject('Chilkat.CreateCS')

loCertStore = loCcs.OpenCurrentUserStore()

loCert = loCertStore.FindCertBySubjectCN("Chilkat Software, Inc.")
IF (loCert = NULL ) THEN
    =MESSAGEBOX(loCert.LastErrorText)
    RELEASE loCertStore
    QUIT
ENDIF

*  Tell the crypt component to use this cert.
loCrypt.SetSigningCert(loCert)

RELEASE loCertStore

*  We can sign any type of file, creating a .p7s as output:
lnSuccess = loCrypt.CreateP7M("test.xml","test.p7m")
IF (lnSuccess = 0) THEN
    =MESSAGEBOX(loCrypt.LastErrorText)
    RELEASE loCert
    QUIT
ENDIF

*  Verify and restore the original file:
loCrypt.SetVerifyCert(loCert)

lnSuccess = loCrypt.VerifyP7M("test.p7m","testRestored.xml")
IF (lnSuccess = 0) THEN
    =MESSAGEBOX(loCrypt.LastErrorText)
    RELEASE loCert
    QUIT
ENDIF

RELEASE loCert

=MESSAGEBOX("Success!")