(PowerBuilder) Verify JWT with EdDSA / Ed25519 Signature

Note: This example requires Chilkat v9.5.0.84 or greater.

Demonstrates how to verify a JWT that was signed using an Ed25519 private key.

This example verifies the EdDSA signature. It also does the following:

• Checks to see if the time constraints ("nbf" and "exp") are valid.
• Recovers the original JOSE header.
• Recovers the original data.

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

integer li_rc
string ls_JsonPubKey
oleobject loo_PubKey
integer li_Success
oleobject loo_Jwt
string ls_Token
integer li_SigVerified
integer li_Leeway
integer li_BTimeValid
string ls_Payload
string ls_JoseHeader

// Demonstrates how to verify a JWT with an EdDSA/Ed25519 Signature
// *** Requires Chilkat v9.5.0.84 or greater.

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

// Use this Ed25519 public key for verification

ls_JsonPubKey = "{~"kty~": ~"OKP~",~"alg~": ~"EdDSA~",~"crv~": ~"Ed25519~",~"x~": ~"11qYAYKxCrfVS_7TyWQHOg7hcvPapiMlrwIaaPcHURo~"}"

loo_PubKey = create oleobject
// Use "Chilkat_9_5_0.PublicKey" for versions of Chilkat < 10.0.0
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
li_Success = loo_PubKey.LoadFromString(ls_JsonPubKey)
if li_Success = 0 then
    Write-Debug loo_PubKey.LastErrorText
    destroy loo_PubKey
    return
end if

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

ls_Token = "eyJhbGciOiJFZERTQSJ9.RXhhbXBsZSBvZiBFZDI1NTE5IHNpZ25pbmc.hgyY0il_MGCjP0JzlnLWG1PPOt7-09PGcvMg3AIbQR6dWbhijcNR4ki4iylGjg5BhVsPt9g7sVvpAr_MuM0KAg"

// First verify the signature.
li_SigVerified = loo_Jwt.VerifyJwtPk(ls_Token,loo_PubKey)
Write-Debug "verified: " + string(li_SigVerified)

if li_SigVerified = 0 then
    Write-Debug loo_Jwt.LastErrorText
    destroy loo_PubKey
    destroy loo_Jwt
    return
end if

// Let's see if the time constraints, if any, are valid.
// The above JWT was created on the afternoon of 16-May-2016, with an expiration of 1 hour.
// If the current system time is before the "nbf" time, or after the "exp" time,
// then IsTimeValid will return false/0.
// Also, we'll allow a leeway of 60 seconds to account for any clock skew.
// Note: If the token has no "nbf" or "exp" claim fields, then IsTimeValid is always true.
li_Leeway = 60
li_BTimeValid = loo_Jwt.IsTimeValid(ls_Token,li_Leeway)
Write-Debug "time constraints valid: " + string(li_BTimeValid)

// Recover the original data (the payload).
ls_Payload = loo_Jwt.GetPayload(ls_Token)
Write-Debug ls_Payload

// Recover the original JOSE header in the same way:
ls_JoseHeader = loo_Jwt.GetHeader(ls_Token)
Write-Debug ls_JoseHeader


destroy loo_PubKey
destroy loo_Jwt