PowerBuilder

Demonstrate RSA Encrypt/Decrypt using BinData

See more RSA Examples

Demonstrates how to RSA encrypt and decrypt data contained in a Chilkat BinData object. PowerBuilder

integer li_rc
integer li_Success
oleobject loo_PubKey
oleobject loo_Rsa
oleobject loo_Bd
integer i
oleobject loo_PrivKey
string ls_Password

li_Success = 0

// The RSA public key is used for encryption, and the private key for decryption.

// The public key's role is to make encryption accessible to anyone while ensuring that
// only the private key holder can decrypt the messages.
// The public key is designed to be widely distributed so anyone can use it to encrypt messages
// intended for the owner of the private key.

// Load our 2048-bit RSA public key.
loo_PubKey = create oleobject
li_rc = loo_PubKey.ConnectToNewObject("Chilkat.PublicKey")
if li_rc < 0 then
    destroy loo_PubKey
    MessageBox("Error","Connecting to COM object failed")
    return
end if
// In all Chilkat methods expecting a path, you pass either absolute or relative paths.
li_Success = loo_PubKey.LoadFromFile("rsaKeys/myTestRsaPublic.pem")
if li_Success = 0 then
    Write-Debug loo_PubKey.LastErrorText
    destroy loo_PubKey
    return
end if

loo_Rsa = create oleobject
li_rc = loo_Rsa.ConnectToNewObject("Chilkat.Rsa")

// Tell RSA to use the public key.
loo_Rsa.UsePublicKey(loo_PubKey)

// RSA encryption is for small amounts of data, on the order of 200 bytes or less.
// The maximum number of bytes that can be RSA encrypted depends
// on the RSA key size and padding scheme (OAEP padding vs PKCS#1 v1.5 padding).
// For specific limits, see: RSA Encryption Maximum Number of Bytes

// Create some binary data to encrypt.
loo_Bd = create oleobject
li_rc = loo_Bd.ConnectToNewObject("Chilkat.BinData")

i = 0
for i = 0 to 49
    loo_Bd.AppendByte(i)
next

// Show the bytes to be encrypted in hex format:
Write-Debug "To be encrypted: " + loo_Bd.GetEncoded("hex")

// To be encrypted: 000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F202122232425262728292A2B2C2D2E2F3031

// RSA encrypt the contents of the bd, replacing the contents with the RSA encrypted data.
loo_Rsa.EncryptBd(loo_Bd,0)

// Now it is encrypted.
Write-Debug "Encrypted size = " + string(loo_Bd.NumBytes)
Write-Debug loo_Bd.GetEncoded("hex")

// Encrypted size = 256
// 749ED9D0A8767C06C09AD9697F654F86B145F966722F9714902C4175BDBD02E68984ECF111D4D461
// EDB4A8E677D399D19CCA60F35C6DE9972F4262880FE9D77DB75915393E8E7DB80AAB5E383013FAEB
// 60C77D1E6FECC9A7C8426976416C6218FE7DA998EE063CE709E79C240F8625F4A56A0A33AFD63F7A
// BA26F2A692B42E878C53B78602C725FE63FF961A46A2B9D436E5E3D9D64AE3F1D1F5AD5F5B47FCD69
// 447306B77F2FD6D766CCAA1A110A3371586B43DF0D7FFE2220D1B305CF9371AC342F849FB0C90CD99E
// C176928D877FE1C0DE1A7CB6EB824FEC7E1DCF90EF2C6BA9F1DFD3EBFBE89C51AF074DC6AE02E544A78
// 5018C36D3D48B2EF5202AF61AC

// ------------------------------------------------------------------------------------------------------------------------
// Let's decrypt, which requires the matching private key...

// Load the matching 2048-bit RSA private key.
loo_PrivKey = create oleobject
li_rc = loo_PrivKey.ConnectToNewObject("Chilkat.PrivateKey")

ls_Password = "secret"
li_Success = loo_PrivKey.LoadAnyFormatFile("rsaKeys/myTestRsaPrivate.pem",ls_Password)
if li_Success = 0 then
    Write-Debug loo_PrivKey.LastErrorText
    destroy loo_PubKey
    destroy loo_Rsa
    destroy loo_Bd
    destroy loo_PrivKey
    return
end if

// Tell the RSA object to use the private key.
loo_Rsa.UsePrivateKey(loo_PrivKey)

// Decrypt
li_Success = loo_Rsa.DecryptBd(loo_Bd,1)
if li_Success = 0 then
    Write-Debug loo_Rsa.LastErrorText
    destroy loo_PubKey
    destroy loo_Rsa
    destroy loo_Bd
    destroy loo_PrivKey
    return
end if

// Examine the contents of bd to see if it now contains the unencrypted original data.
Write-Debug "Decrypted: " + loo_Bd.GetEncoded("hex")

// Decrypted: 000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F202122232425262728292A2B2C2D2E2F3031


destroy loo_PubKey
destroy loo_Rsa
destroy loo_Bd
destroy loo_PrivKey