(PowerBuilder) AES and CHACHA20 Encrypt/Decrypt Text

Demonstrates the use of the new EncryptSb and DecryptSb methods introduced in Chilkat v9.5.0.67 to encrypt/decrypt the contents of StringBuilder objects.

Note: This example requires Chilkat v9.5.0.67 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

integer li_rc
integer li_Success
oleobject loo_Sb
integer i
oleobject loo_Crypt
string ls_IvHex
string ls_KeyHex
oleobject loo_BdEncrypted
oleobject loo_SbOriginal

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

// First build a string to be encrypted
loo_Sb = create oleobject
// Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
li_rc = loo_Sb.ConnectToNewObject("Chilkat.StringBuilder")
if li_rc < 0 then
    destroy loo_Sb
    MessageBox("Error","Connecting to COM object failed")
    return
end if
i = 1
do while i < 10
    loo_Sb.AppendInt(i)
    loo_Sb.Append(" the quick brown fox jumped over the lazy dog.~r~n")
    i = i + 1
loop

Write-Debug loo_Sb.GetAsString()

// The string to be encrypted looks like this:

// 1 the quick brown fox jumped over the lazy dog.
// 2 the quick brown fox jumped over the lazy dog.
// 3 the quick brown fox jumped over the lazy dog.
// 4 the quick brown fox jumped over the lazy dog.
// 5 the quick brown fox jumped over the lazy dog.
// 6 the quick brown fox jumped over the lazy dog.
// ...

loo_Crypt = create oleobject
// Use "Chilkat_9_5_0.Crypt2" for versions of Chilkat < 10.0.0
li_rc = loo_Crypt.ConnectToNewObject("Chilkat.Crypt2")

// Specify the encryption to be used.
// First we'll do AES-128 CBC
loo_Crypt.CryptAlgorithm = "aes"
loo_Crypt.CipherMode = "cbc"
loo_Crypt.KeyLength = 128

ls_IvHex = "000102030405060708090A0B0C0D0E0F"
loo_Crypt.SetEncodedIV(ls_IvHex,"hex")

ls_KeyHex = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"
loo_Crypt.SetEncodedKey(ls_KeyHex,"hex")

// When EncryptSb is called, the contents of the source (sb)
// remains unmodified.  The encrypted bytes are written into bdEncrypted.
// If bdEncrypted already contained data, it is replaced with the encrypted bytes.
loo_BdEncrypted = create oleobject
// Use "Chilkat_9_5_0.BinData" for versions of Chilkat < 10.0.0
li_rc = loo_BdEncrypted.ConnectToNewObject("Chilkat.BinData")

li_Success = loo_Crypt.EncryptSb(loo_Sb,loo_BdEncrypted)
if li_Success <> 1 then
    Write-Debug loo_Crypt.LastErrorText
    destroy loo_Sb
    destroy loo_Crypt
    destroy loo_BdEncrypted
    return
end if

// Examine the encrypted bytes:
Write-Debug loo_BdEncrypted.GetEncoded("base64_mime")

// Sample encrypted data:

// 0DdNZ22ckMMJBiaKhAu3wUEfh16XW356NIUsDmNs/xwbHe/p1201OmpfzwXwKktkAefu2pckrBgC
// df+1w8lRo+KAy5n5wlAgMGM/UrsVJsp0BmDPk1vaxKrmrGpSXOVCQs1n2+0atIs5YLiOG+Va3+Mi
// EQNb4YK7bNMmvt0++irBxTiGnkx/RncfKwgkbBUpl2x7yV13MW6lapDT6Md0DKAMsTXFJYGeIdEf
// g2uxDDQzI5gUOUHTMrXQ8paD/K76KKB9Jpp/kAM9z8g/d8KUmuphA7KI64d38xsgOmcITlbhlCQ2
// PDkcU6RRzX0FUTUSMgQukhy0jkLZEjHX9poKJD+iJTOkcQUC3OqR9hKhSrvIgJN4lxdR71MheOoQ
// 2wmvRdq+agTWWh333Vmb6J6yDV79aSpnqEDrA8Ks7Xzciol0gve91+JtVJlJKjWwEzWEU8GxF7Q8
// eaWI70lsC5nTLGcbqgKu6gzkzHlHyHaE2FAQA/d5I2dvfsAYUQCza0Zdyw8mmTtHhlP2Tfxj1uPv
// H4Q7BGuKnx3SWT2CnpbX4091w7KzLAztrbFBo/Tf9w8ZpgTK9k1ryfW9/xnk6rW6iQ==

// Decrypt to restore back to the original:
loo_SbOriginal = create oleobject
// Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
li_rc = loo_SbOriginal.ConnectToNewObject("Chilkat.StringBuilder")

li_Success = loo_Crypt.DecryptSb(loo_BdEncrypted,loo_SbOriginal)
if li_Success <> 1 then
    Write-Debug loo_Crypt.LastErrorText
    destroy loo_Sb
    destroy loo_Crypt
    destroy loo_BdEncrypted
    destroy loo_SbOriginal
    return
end if

// Examine the original data:
Write-Debug loo_SbOriginal.GetAsString()

// ----------------------------------------------------------------------------------
// To do chacha20 encryption, just change the settings:

loo_Crypt.CryptAlgorithm = "chacha20"
loo_Crypt.KeyLength = 256
// The initial count is the initial block counter for the chacha20 algorithm.
// It can be any integer, but must be set to the same when decrypting.
loo_Crypt.InitialCount = 22

// EncryptSb completely replaces the contents of bdEncrypted.
li_Success = loo_Crypt.EncryptSb(loo_Sb,loo_BdEncrypted)

// However.. DecryptSb appends the decrypted text to whatever may
// have already existed within sbOriginal.
li_Success = loo_Crypt.DecryptSb(loo_BdEncrypted,loo_SbOriginal)

Write-Debug "----"
Write-Debug "The original data should be here twice.  Once from the AES decrypt, and again from the chacha20 decrypt."
Write-Debug loo_SbOriginal.GetAsString()
Write-Debug "Success."


destroy loo_Sb
destroy loo_Crypt
destroy loo_BdEncrypted
destroy loo_SbOriginal