(Lianja) Encrypt/Decrypt using PFX to produce -----BEGIN PKCS7----- ... -----END PKCS7-----

First we encrypt using a certificate + public key to produce output such as:

-----BEGIN PKCS7-----
MIIHPwYJKoZIhvcNAQcEoIIHMDCCBywC ...
...
...
-----END PKCS7-----

Chilkat Lianja Extension Download Chilkat Lianja Extension

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

loCrypt = createobject("CkCrypt2")

// Specify the encryption to be used.
// "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
loCrypt.CryptAlgorithm = "pki"
loCrypt.Pkcs7CryptAlg = "aes"
loCrypt.KeyLength = 128
loCrypt.OaepHash = "sha256"
loCrypt.OaepPadding = .T.

// A certificate is needed as the encryption key.
// Althought the PFX contains the associated private key, we don't need it for encryption.
// (A certificate usually contains the public key by default.)
loCert = createobject("CkCert")
llSuccess = loCert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
if (llSuccess <> .T.) then
    ? loCert.LastErrorText
    release loCrypt
    release loCert
    return
endif

// Tell the crypt object to use the certificate.
loCrypt.SetEncryptCert(loCert)

lcToBeEncrypted = "This string is to be encrypted."

// Get the result in multi-line BASE64 MIME format.
loCrypt.EncodingMode = "base64_mime"

lcEncryptedStr = loCrypt.EncryptStringENC(lcToBeEncrypted)
if (llSuccess <> .T.) then
    ? loCrypt.LastErrorText
    release loCrypt
    release loCert
    return
endif

// Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
loSb = createobject("CkStringBuilder")
loSb.AppendLine("-----BEGIN PKCS7-----",.T.)
loSb.Append(lcEncryptedStr)
loSb.AppendLine("-----END PKCS7-----",.T.)

lcOutStr = loSb.GetAsString()

? lcOutStr

// Sample output:

// -----BEGIN PKCS7-----
// MIICXAYJKoZIhvcNAQcDoIICTTCCAkkCAQAxggH0MIIB8AIBADCBrDCBlzELMAkGA1UEBhMCR0Ix
// GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR
// Q09NT0RPIENBIExpbWl0ZWQxPTA7BgNVBAMTNENPTU9ETyBSU0EgQ2xpZW50IEF1dGhlbnRpY2F0
// aW9uIGFuZCBTZWN1cmUgRW1haWwgQ0ECEB6M1ZwZdZU7LrAIdurulmUwOAYJKoZIhvcNAQEHMCug
// DzANBglghkgBZQMEAgEFAKEYMBYGCSqGSIb3DQEBCDAJBgUrDgMCGgUABIIBAK/BZG/iXJ8az7zL
// 8EQ77mc+oDPQ4w1hyytK2ip4djkPVvTfYhcoDQ+G/DBU+urJfrVBi5H9gmpXwYyfKlyUxBVRVEJl
// V/V5QQi4JmNTFbmgWh5tp9zDS98l6A2Va4Zs0Wy/owGLfvwitlxd1dsfVAV2hmBYS24BMpNcty5/
// 0atcKYmSou13G78ztTKdMy1tECgZy8kerMsPdDQbSxEZkT3KpQ8C5uEQqYF3bIVaeZzha/Ywieh/
// tvO0T4aAmeJufwkNdVECmU7kuhnNaVPXknFl7jeibTl6zA/VcJKBKcIYT9FRC7KjdooI8q+jtQ/V
// k6RP4POaowkFg1QWRPEWeqIwTAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBAgQQEEFQduqeJqXQXzy4
// JpkoDoAgdldJDB9zEkpMpgr5/fR2iLvh5kC6BPfhOYjsawBY4Ok=
// -----END PKCS7-----

// ----------------------------------------------------------------------------------------
// Let's Decrypt the above string.

// Start with what was produced above..
loSb.Clear()
llBCrlf = .T.
loSb.AppendLine("-----BEGIN PKCS7-----",llBCrlf)
loSb.AppendLine("MIICXAYJKoZIhvcNAQcDoIICTTCCAkkCAQAxggH0MIIB8AIBADCBrDCBlzELMAkGA1UEBhMCR0Ix",llBCrlf)
loSb.AppendLine("GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR",llBCrlf)
loSb.AppendLine("Q09NT0RPIENBIExpbWl0ZWQxPTA7BgNVBAMTNENPTU9ETyBSU0EgQ2xpZW50IEF1dGhlbnRpY2F0",llBCrlf)
loSb.AppendLine("aW9uIGFuZCBTZWN1cmUgRW1haWwgQ0ECEB6M1ZwZdZU7LrAIdurulmUwOAYJKoZIhvcNAQEHMCug",llBCrlf)
loSb.AppendLine("DzANBglghkgBZQMEAgEFAKEYMBYGCSqGSIb3DQEBCDAJBgUrDgMCGgUABIIBAK/BZG/iXJ8az7zL",llBCrlf)
loSb.AppendLine("8EQ77mc+oDPQ4w1hyytK2ip4djkPVvTfYhcoDQ+G/DBU+urJfrVBi5H9gmpXwYyfKlyUxBVRVEJl",llBCrlf)
loSb.AppendLine("V/V5QQi4JmNTFbmgWh5tp9zDS98l6A2Va4Zs0Wy/owGLfvwitlxd1dsfVAV2hmBYS24BMpNcty5/",llBCrlf)
loSb.AppendLine("0atcKYmSou13G78ztTKdMy1tECgZy8kerMsPdDQbSxEZkT3KpQ8C5uEQqYF3bIVaeZzha/Ywieh/",llBCrlf)
loSb.AppendLine("tvO0T4aAmeJufwkNdVECmU7kuhnNaVPXknFl7jeibTl6zA/VcJKBKcIYT9FRC7KjdooI8q+jtQ/V",llBCrlf)
loSb.AppendLine("k6RP4POaowkFg1QWRPEWeqIwTAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBAgQQEEFQduqeJqXQXzy4",llBCrlf)
loSb.AppendLine("JpkoDoAgdldJDB9zEkpMpgr5/fR2iLvh5kC6BPfhOYjsawBY4Ok=",llBCrlf)
loSb.AppendLine("-----END PKCS7-----",llBCrlf)

loDecrypt = createobject("CkCrypt2")
loDecrypt.CryptAlgorithm = "pki"

// Use the same cert + private key from the PFX above.
// For decryption, we need the private key.  Given that the certificate was loaded from a PFX,
// we should already have it.
llSuccess = loDecrypt.SetDecryptCert(loCert)

loDecrypt.EncodingMode = "base64"
lcDecryptedText = loDecrypt.DecryptStringENC(loSb.GetBetween("-----BEGIN PKCS7-----","-----END PKCS7-----"))

? lcDecryptedText


release loCrypt
release loCert
release loSb
release loDecrypt