PowerBuilder

JWE with DEFLATE Compression

See more JSON Web Encryption (JWE) Examples

Demonstrates how to DEFLATE ("zip") compress the JWE payload prior to encryption.

Note: This example requires Chilkat v9.5.0.66 or greater.

PowerBuilder

integer li_rc
integer li_Success
oleobject loo_SbPlainText
integer li_BCrLf
string ls_Line
oleobject loo_Jwe
oleobject loo_JweProtHdr
string ls_AesWrappingKey
oleobject loo_SbJweCompressed
oleobject loo_SbJweUncompressed
oleobject loo_Jwe2
oleobject loo_SbOriginalText

li_Success = 0

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

// Note: This example requires Chilkat v9.5.0.66 or greater.

// Create some plaintext to be encrypted.
// This example will demonstrate with and without DEFLATE (zip) compression.
loo_SbPlainText = create oleobject
li_rc = loo_SbPlainText.ConnectToNewObject("Chilkat.StringBuilder")
if li_rc < 0 then
    destroy loo_SbPlainText
    MessageBox("Error","Connecting to COM object failed")
    return
end if
li_BCrLf = 1
ls_Line = "Live long and prosper."
loo_SbPlainText.AppendLine(ls_Line,li_BCrLf)
loo_SbPlainText.AppendLine(ls_Line,li_BCrLf)
loo_SbPlainText.AppendLine(ls_Line,li_BCrLf)
loo_SbPlainText.AppendLine(ls_Line,li_BCrLf)

// The text to be encrypted:
Write-Debug loo_SbPlainText.GetAsString()

loo_Jwe = create oleobject
li_rc = loo_Jwe.ConnectToNewObject("Chilkat.Jwe")

// Build the JWE Protected Header: {"alg":"A128KW","enc":"A128CBC-HS256","zip":"DEF"}
// The "zip":"DEF" parameter indicates that the plaintext payload should
// be compressed prior to encryption.
loo_JweProtHdr = create oleobject
li_rc = loo_JweProtHdr.ConnectToNewObject("Chilkat.JsonObject")

loo_JweProtHdr.AppendString("alg","A128KW")
loo_JweProtHdr.AppendString("enc","A128CBC-HS256")
loo_JweProtHdr.AppendString("zip","DEF")
loo_Jwe.SetProtectedHeader(loo_JweProtHdr)

// Set the AES key wrap key:
ls_AesWrappingKey = "GawgguFyGrWKav7AX4VKUg"
loo_Jwe.SetWrappingKey(0,ls_AesWrappingKey,"base64url")

// Encrypt and return the JWE in sbJweCompressed:
loo_SbJweCompressed = create oleobject
li_rc = loo_SbJweCompressed.ConnectToNewObject("Chilkat.StringBuilder")

li_Success = loo_Jwe.EncryptSb(loo_SbPlainText,"utf-8",loo_SbJweCompressed)
if li_Success <> 1 then
    Write-Debug loo_Jwe.LastErrorText
    destroy loo_SbPlainText
    destroy loo_Jwe
    destroy loo_JweProtHdr
    destroy loo_SbJweCompressed
    return
end if

// Show the compressed JWE:
Write-Debug loo_SbJweCompressed.GetAsString()
Write-Debug "size of compressed JWE: " + string(loo_SbJweCompressed.Length)

// Now create a JWE without compression.
loo_JweProtHdr.Delete("zip")
// Make sure to update the shared protected header:
loo_Jwe.SetProtectedHeader(loo_JweProtHdr)

loo_SbJweUncompressed = create oleobject
li_rc = loo_SbJweUncompressed.ConnectToNewObject("Chilkat.StringBuilder")

li_Success = loo_Jwe.EncryptSb(loo_SbPlainText,"utf-8",loo_SbJweUncompressed)
if li_Success <> 1 then
    Write-Debug loo_Jwe.LastErrorText
    destroy loo_SbPlainText
    destroy loo_Jwe
    destroy loo_JweProtHdr
    destroy loo_SbJweCompressed
    destroy loo_SbJweUncompressed
    return
end if

// Show the uncompressed JWE:
Write-Debug loo_SbJweUncompressed.GetAsString()
Write-Debug "size of uncompressed JWE: " + string(loo_SbJweUncompressed.Length)

// Decrypting is the same whether compression is used or not.
// The "zip" header in the JWE indicates that the payload should be 
// automatically decompressed (inflated) after decrypting.
loo_Jwe2 = create oleobject
li_rc = loo_Jwe2.ConnectToNewObject("Chilkat.Jwe")

li_Success = loo_Jwe2.LoadJweSb(loo_SbJweCompressed)
if li_Success <> 1 then
    Write-Debug loo_Jwe2.LastErrorText
    destroy loo_SbPlainText
    destroy loo_Jwe
    destroy loo_JweProtHdr
    destroy loo_SbJweCompressed
    destroy loo_SbJweUncompressed
    destroy loo_Jwe2
    return
end if

// Set the AES wrap key.
loo_Jwe2.SetWrappingKey(0,ls_AesWrappingKey,"base64url")

// Decrypt (also automatically decompresses).
loo_SbOriginalText = create oleobject
li_rc = loo_SbOriginalText.ConnectToNewObject("Chilkat.StringBuilder")

li_Success = loo_Jwe2.DecryptSb(0,"utf-8",loo_SbOriginalText)
if li_Success <> 1 then
    Write-Debug loo_Jwe2.LastErrorText
    destroy loo_SbPlainText
    destroy loo_Jwe
    destroy loo_JweProtHdr
    destroy loo_SbJweCompressed
    destroy loo_SbJweUncompressed
    destroy loo_Jwe2
    destroy loo_SbOriginalText
    return
end if

Write-Debug "original text from compressed JWE: "
Write-Debug loo_SbOriginalText.GetAsString()

// -----------------------------------------------------------
// Do the same with the uncompressed JWE

li_Success = loo_Jwe2.LoadJweSb(loo_SbJweUncompressed)
if li_Success <> 1 then
    Write-Debug loo_Jwe2.LastErrorText
    destroy loo_SbPlainText
    destroy loo_Jwe
    destroy loo_JweProtHdr
    destroy loo_SbJweCompressed
    destroy loo_SbJweUncompressed
    destroy loo_Jwe2
    destroy loo_SbOriginalText
    return
end if

// Set the AES wrap key.
loo_Jwe2.SetWrappingKey(0,ls_AesWrappingKey,"base64url")

// Decrypt.
loo_SbOriginalText.Clear()
li_Success = loo_Jwe2.DecryptSb(0,"utf-8",loo_SbOriginalText)
if li_Success <> 1 then
    Write-Debug loo_Jwe2.LastErrorText
    destroy loo_SbPlainText
    destroy loo_Jwe
    destroy loo_JweProtHdr
    destroy loo_SbJweCompressed
    destroy loo_SbJweUncompressed
    destroy loo_Jwe2
    destroy loo_SbOriginalText
    return
end if

Write-Debug "original text from uncompressed JWE: "
Write-Debug loo_SbOriginalText.GetAsString()

// ------------------------------------------------
// The output of this example is:
// (Note: Your output data will be different because the content encryption key is randomly generated.)

// eyJhbGciOiJBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2IiwiemlwIjoiREVGIn0.xuW-pEAIdEUFnk10m8ocursvktO8Of9ByCCAt6LgKkkOtCWCUn1kQw.zpGj-9WVni3cQxyOuZbcGA.0hzP1myua3oYpUHwCIY_3edBUREbUpLaX6wYuJduOdI.Ppc6aEO3y3B8BJ1FKMPjlA
// size of compressed JWE: 212
// eyJhbGciOiJBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2In0.N4KeyC7nnSFkieJOyE24_zKeuV_m7v5UKoJb1TgV4Yc_r2RzUPNvyA.6AEdyXSCKx-iMmUJyypSLg.QpixfyrwhGpmwUDp623viik4smPav7vwPLiC2r-V-jwnSfEH3mxWu6DbrIz3mixaqATwynmEBzVPxvS9jTXpSAGCnniib4_0WoPl3r_wF5tlsKOEe--jpNso-DKd1Tp8jJxj3JkFWt3IRnUUKGj17g.sBfDwFc5fzpaI-UW8-SW4g
// size of uncompressed JWE: 303
// original text from compressed JWE: 
// Live long and prosper.
// Live long and prosper.
// Live long and prosper.
// Live long and prosper.
// 
// original text from uncompressed JWE: 
// Live long and prosper.
// Live long and prosper.
// Live long and prosper.
// Live long and prosper.
// 


destroy loo_SbPlainText
destroy loo_Jwe
destroy loo_JweProtHdr
destroy loo_SbJweCompressed
destroy loo_SbJweUncompressed
destroy loo_Jwe2
destroy loo_SbOriginalText