(Xojo Plugin) RSA Encrypt RSA/ECB/OAEPWithSHA1AndMGF1Padding

Demonstrates how to RSA encrypt using RSA/ECB/OAEPWithSHA1AndMGF1Padding. Also demonstrates RSA/ECB/OAEPWithSHA-256AndMGF1Padding. Both of these terms are from Java's JCE. Note: In this context, "ECB" doesn't actually mean anything. It's a symmetric cipher mode that doesn't apply (or make sense) in this context.

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

Dim rsa As New Chilkat.Rsa

// First load a public key object with a public key.
// In this case, we'll load it from a file.
Dim pubkey As New Chilkat.PublicKey
Dim success As Boolean
success = pubkey.LoadFromFile("qa_data/pem/rsa_public.pem")
If (success <> True) Then
    System.DebugLog(pubkey.LastErrorText)
    Return
End If

// RSA encryption is limited to small amounts of data. The limit
// is typically a few hundred bytes and is based on the key size and
// padding (OAEP vs. PKCS1_5).  RSA encryption is typically used for
// encrypting hashes or symmetric (bulk encryption algorithm) secret keys.
Dim plainText As String
plainText = "Time is an illusion. Lunchtime doubly so."

// Import the public key to be used for encrypting.
success = rsa.ImportPublicKeyObj(pubkey)

// To get OAEP padding, set the OaepPadding property:
rsa.OaepPadding = True

// To use SHA1 or SHA-256, set the OaepHash property
rsa.OaepHash = "sha256"
// for SHA1 --
rsa.OaepHash = "sha1"

// Indicate we'll want hex output
rsa.EncodingMode = "hex"

// Encrypt..
Dim usePrivateKey As Boolean
usePrivateKey = False
Dim encryptedStr As String
encryptedStr = rsa.EncryptStringENC(plainText,usePrivateKey)
System.DebugLog(encryptedStr)

// -------------------------------------------------
// Now decrypt with the matching private key.
Dim rsa2 As New Chilkat.Rsa

Dim privKey As New Chilkat.PrivateKey
success = privKey.LoadEncryptedPem("qa_data/pem/rsa_passwd.pem","passwd")
If (success <> True) Then
    System.DebugLog(privKey.LastErrorText)
    Return
End If

success = rsa2.ImportPrivateKeyObj(privKey)

// Make sure we have the same settings used for encryption.
rsa2.OaepPadding = True
rsa2.EncodingMode = "hex"
rsa2.OaepHash = "sha1"

Dim originalStr As String
originalStr = rsa2.DecryptStringENC(encryptedStr,True)

System.DebugLog(originalStr)