Xbase++ Requires Chilkat v11.0.0+

JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples

Creates a JSON Web Signatures (JWS) using HMAC SHA-256. Xbase++

LOCAL nSuccess
LOCAL oJwsProtHdr
LOCAL oJws
LOCAL cHmacKey
LOCAL nSignatureIndex
LOCAL nBIncludeBom
LOCAL cPayloadStr
LOCAL cJwsCompact
LOCAL oJws2
LOCAL v
LOCAL oJoseHeader

nSuccess := 0

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

//  First create the JWS Protected Header
oJwsProtHdr := CreateObject("Chilkat.JsonObject")
oJwsProtHdr:AppendString("typ", "JWT")
oJwsProtHdr:AppendString("alg", "HS256")
? "JWS Protected Header: " + oJwsProtHdr:Emit()

//  Output:
//  JWS Protected Header: {"typ":"JWT","alg":"HS256"}

oJws := CreateObject("Chilkat.Jws")

//  Set the HMAC key:
cHmacKey := "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow"
nSignatureIndex := 0
oJws:SetMacKey(nSignatureIndex, cHmacKey, "base64url")

//  Set the protected header:
oJws:SetProtectedHeader(nSignatureIndex, oJwsProtHdr)

//  Set the payload.
nBIncludeBom := 0
cPayloadStr := "In our village, folks say God crumbles up the old moon into stars."
oJws:SetPayload(cPayloadStr, "utf-8", nBIncludeBom)

//  Create the JWS
//  By default, the compact serialization is used.
cJwsCompact := oJws:CreateJws()
IF (oJws:LastMethodSuccess == 0)
    ? oJws:LastErrorText
    oJwsProtHdr:destroy()
    oJws:destroy()
    RETURN
ENDIF

? "JWS: " + cJwsCompact

//  sample output:
//  JWS: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.bsYsi8HJ0N6OqGI1hKQ9QQRNPxxA5qMpcHLtOvXatk8

//  Now load the JWS, validate, and recover the original text.
oJws2 := CreateObject("Chilkat.Jws")

//  Load the JWS.
nSuccess := oJws2:LoadJws(cJwsCompact)

//  Set the MAC key used for validation.
nSignatureIndex := 0
oJws2:SetMacKey(nSignatureIndex, cHmacKey, "base64url")

//  Validate the 1st (and only) signature at index 0..
v := oJws2:Validate(nSignatureIndex)
IF (v < 0)
    //  Perhaps Chilkat was not unlocked or the trial expired..
    ? "Method call failed for some other reason."
    ? oJws2:LastErrorText
    oJwsProtHdr:destroy()
    oJws:destroy()
    oJws2:destroy()
    RETURN
ENDIF

IF (v == 0)
    ? "Invalid signature.  The MAC key was incorrect, the JWS was invalid, or both."
    oJwsProtHdr:destroy()
    oJws:destroy()
    oJws2:destroy()
    RETURN
ENDIF

//  If we get here, the signature was validated..
? "Signature validated."

//  Recover the original content:
? oJws2:GetPayload("utf-8")

//  Examine the protected header:

oJoseHeader := CreateObject("Chilkat.JsonObject")
nSuccess := oJws2:GetProtectedH(nSignatureIndex, oJoseHeader)
IF (nSuccess == 0)
    ? oJws2:LastErrorText
    oJwsProtHdr:destroy()
    oJws:destroy()
    oJws2:destroy()
    oJoseHeader:destroy()
    RETURN
ENDIF

oJoseHeader:EmitCompact := 0

? "Protected (JOSE) header:"
? oJoseHeader:Emit()

//  Output:

//  	Signature validated.
//  	In our village, folks say God crumbles up the old moon into stars.
//  	Protected (JOSE) header:
//  	{ 
//  	  "typ": "JWT",
//  	  "alg": "HS256"
//  	}

oJwsProtHdr:destroy()
oJws:destroy()
oJws2:destroy()
oJoseHeader:destroy()