(PowerBuilder) JWS Using RSASSA-PSS using SHA-256 and MGF1 with SHA-256

Creates and validates a JSON Web Signature (JWS) using RSASSA-PSS using SHA-256 and MGF1 with SHA-256.

Chilkat supports all of the following JWS algorithms:

   +--------------+-------------------------------+--------------------+
   | "alg" Param  | Digital Signature or MAC      | Implementation     |
   | Value        | Algorithm                     | Requirements       |
   +--------------+-------------------------------+--------------------+
   | HS256        | HMAC using SHA-256            | Required           |
   | HS384        | HMAC using SHA-384            | Optional           |
   | HS512        | HMAC using SHA-512            | Optional           |
   | RS256        | RSASSA-PKCS1-v1_5 using       | Recommended        |
   |              | SHA-256                       |                    |
   | RS384        | RSASSA-PKCS1-v1_5 using       | Optional           |
   |              | SHA-384                       |                    |
   | RS512        | RSASSA-PKCS1-v1_5 using       | Optional           |
   |              | SHA-512                       |                    |
   | ES256        | ECDSA using P-256 and SHA-256 | Recommended+       |
   | ES384        | ECDSA using P-384 and SHA-384 | Optional           |
   | ES512        | ECDSA using P-521 and SHA-512 | Optional           |
   | PS256        | RSASSA-PSS using SHA-256 and  | Optional           |
   |              | MGF1 with SHA-256             |                    |
   | PS384        | RSASSA-PSS using SHA-384 and  | Optional           |
   |              | MGF1 with SHA-384             |                    |
   | PS512        | RSASSA-PSS using SHA-512 and  | Optional           |
   |              | MGF1 with SHA-512             |                    |
   +--------------+-------------------------------+--------------------+

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

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

integer li_rc
oleobject loo_SbJwk
oleobject loo_RsaKey
integer li_Success
oleobject loo_JwsProtHdr
oleobject loo_Jws
integer li_SignatureIndex
integer li_BIncludeBom
string ls_PayloadStr
string ls_JwsCompact
oleobject loo_Jws2
oleobject loo_RsaPubKey
integer v
oleobject loo_JoseHeader

// 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.

// Use the following RSA key loaded from JWK format.
loo_SbJwk = create oleobject
li_rc = loo_SbJwk.ConnectToNewObject("Chilkat_9_5_0.StringBuilder")
if li_rc < 0 then
    destroy loo_SbJwk
    MessageBox("Error","Connecting to COM object failed")
    return
end if
loo_SbJwk.Append("{\"kty\":\"RSA\",")
loo_SbJwk.Append("\"n\":\"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx")
loo_SbJwk.Append("HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs")
loo_SbJwk.Append("D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH")
loo_SbJwk.Append("SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV")
loo_SbJwk.Append("MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8")
loo_SbJwk.Append("NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ\",")
loo_SbJwk.Append("\"e\":\"AQAB\",")
loo_SbJwk.Append("\"d\":\"Eq5xpGnNCivDflJsRQBXHx1hdR1k6Ulwe2JZD50LpXyWPEAeP88vLNO97I")
loo_SbJwk.Append("jlA7_GQ5sLKMgvfTeXZx9SE-7YwVol2NXOoAJe46sui395IW_GO-pWJ1O0")
loo_SbJwk.Append("BkTGoVEn2bKVRUCgu-GjBVaYLU6f3l9kJfFNS3E0QbVdxzubSu3Mkqzjkn")
loo_SbJwk.Append("439X0M_V51gfpRLI9JYanrC4D4qAdGcopV_0ZHHzQlBjudU2QvXt4ehNYT")
loo_SbJwk.Append("CBr6XCLQUShb1juUO1ZdiYoFaFQT5Tw8bGUl_x_jTj3ccPDVZFD9pIuhLh")
loo_SbJwk.Append("BOneufuBiB4cS98l2SR_RQyGWSeWjnczT0QU91p1DhOVRuOopznQ\",")
loo_SbJwk.Append("\"p\":\"4BzEEOtIpmVdVEZNCqS7baC4crd0pqnRH_5IB3jw3bcxGn6QLvnEtfdUdi")
loo_SbJwk.Append("YrqBdss1l58BQ3KhooKeQTa9AB0Hw_Py5PJdTJNPY8cQn7ouZ2KKDcmnPG")
loo_SbJwk.Append("BY5t7yLc1QlQ5xHdwW1VhvKn-nXqhJTBgIPgtldC-KDV5z-y2XDwGUc\",")
loo_SbJwk.Append("\"q\":\"uQPEfgmVtjL0Uyyx88GZFF1fOunH3-7cepKmtH4pxhtCoHqpWmT8YAmZxa")
loo_SbJwk.Append("ewHgHAjLYsp1ZSe7zFYHj7C6ul7TjeLQeZD_YwD66t62wDmpe_HlB-TnBA")
loo_SbJwk.Append("-njbglfIsRLtXlnDzQkv5dTltRJ11BKBBypeeF6689rjcJIDEz9RWdc\",")
loo_SbJwk.Append("\"dp\":\"BwKfV3Akq5_MFZDFZCnW-wzl-CCo83WoZvnLQwCTeDv8uzluRSnm71I3Q")
loo_SbJwk.Append("CLdhrqE2e9YkxvuxdBfpT_PI7Yz-FOKnu1R6HsJeDCjn12Sk3vmAktV2zb")
loo_SbJwk.Append("34MCdy7cpdTh_YVr7tss2u6vneTwrA86rZtu5Mbr1C1XsmvkxHQAdYo0\",")
loo_SbJwk.Append("\"dq\":\"h_96-mK1R_7glhsum81dZxjTnYynPbZpHziZjeeHcXYsXaaMwkOlODsWa")
loo_SbJwk.Append("7I9xXDoRwbKgB719rrmI2oKr6N3Do9U0ajaHF-NKJnwgjMd2w9cjz3_-ky")
loo_SbJwk.Append("NlxAr2v4IKhGNpmM5iIgOS1VZnOZ68m6_pbLBSp3nssTdlqvd0tIiTHU\",")
loo_SbJwk.Append("\"qi\":\"IYd7DHOhrWvxkwPQsRM2tOgrjbcrfvtQJipd-DlcxyVuuM9sQLdgjVk2o")
loo_SbJwk.Append("y26F0EmpScGLq2MowX7fhd_QJQ3ydy5cY7YIBi87w93IKLEdfnbJtoOPLU")
loo_SbJwk.Append("W0ITrJReOgo1cq9SbsxYawBgfp_gh6A5603k2-ZQwVK0JKSHuLFkuQ3U\"")
loo_SbJwk.Append("}")

loo_RsaKey = create oleobject
li_rc = loo_RsaKey.ConnectToNewObject("Chilkat_9_5_0.PrivateKey")

// Note: This example loads the RSA key from JWK format.  Any format can be loaded
// into the private key object. (See the online reference documentation..)
li_Success = loo_RsaKey.LoadJwk(loo_SbJwk.GetAsString())
if li_Success <> 1 then
    Write-Debug loo_RsaKey.LastErrorText
    destroy loo_SbJwk
    destroy loo_RsaKey
    return
end if

// Create the JWS Protected Header
loo_JwsProtHdr = create oleobject
li_rc = loo_JwsProtHdr.ConnectToNewObject("Chilkat_9_5_0.JsonObject")

loo_JwsProtHdr.AppendString("alg","PS256")

loo_Jws = create oleobject
li_rc = loo_Jws.ConnectToNewObject("Chilkat_9_5_0.Jws")

// Set the protected header:
li_SignatureIndex = 0
loo_Jws.SetProtectedHeader(li_SignatureIndex,loo_JwsProtHdr)

// Set the RSA key:
loo_Jws.SetPrivateKey(li_SignatureIndex,loo_RsaKey)

// Set the payload.
li_BIncludeBom = 0
ls_PayloadStr = "In our village, folks say God crumbles up the old moon into stars."
loo_Jws.SetPayload(ls_PayloadStr,"utf-8",li_BIncludeBom)

// Create the JWS
// By default, the compact serialization is used.
ls_JwsCompact = loo_Jws.CreateJws()
if loo_Jws.LastMethodSuccess <> 1 then
    Write-Debug loo_Jws.LastErrorText
    destroy loo_SbJwk
    destroy loo_RsaKey
    destroy loo_JwsProtHdr
    destroy loo_Jws
    return
end if

Write-Debug "JWS: " + ls_JwsCompact

// Note: RSA PSS padding uses random values, so the output will be different each time a signature is produced.
// sample output:
// JWS: eyJhbGciOiJQUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.TRWhwRo5dMv9-8OzrInfJTwmUGYgjLfHk8lqF072ND-FmLWEBnUTOpY8oJXp8FdWw2SalbdOeNlrtlJjwk4XK8Ql2iJ_2qMCtxsvLPhKBOqFoAF4aBvTOEDVJDxf0DaBSiydEEtfTVV2iwBcjWabu5J2XieR5y7QZQtuHsn7T3qKBvCcCejN3Y2oqAT3qMHvu1fTms1r_91wBn_K7Wjd9UkZ1n02qQcUHJznR_OF2BgN7_KWIDAF9ZS9keoju2NPpPelO4yxa2XUPnehY3G7dHKoCxUEQR4d2Xc5voqDASTVCDqQS4PVOZdvT3Ein6-SanAlCwbWBbkvT8g6-5PImQ

// Now load the JWS, validate, and recover the original text.
loo_Jws2 = create oleobject
li_rc = loo_Jws2.ConnectToNewObject("Chilkat_9_5_0.Jws")

// Load the JWS.
li_Success = loo_Jws2.LoadJws(ls_JwsCompact)

loo_RsaPubKey = loo_RsaKey.GetPublicKey()

// Set the RSA public key used for validation.
li_SignatureIndex = 0
loo_Jws2.SetPublicKey(li_SignatureIndex,loo_RsaPubKey)
destroy loo_RsaPubKey

// Validate the 1st (and only) signature at index 0..
v = loo_Jws2.Validate(li_SignatureIndex)
if v < 0 then
    // Perhaps Chilkat was not unlocked or the trial expired..
    Write-Debug "Method call failed for some other reason."
    Write-Debug loo_Jws2.LastErrorText
    destroy loo_SbJwk
    destroy loo_RsaKey
    destroy loo_JwsProtHdr
    destroy loo_Jws
    destroy loo_Jws2
    return
end if

if v = 0 then
    Write-Debug "Invalid signature.  The RSA key was incorrect, the JWS was invalid, or both."
    destroy loo_SbJwk
    destroy loo_RsaKey
    destroy loo_JwsProtHdr
    destroy loo_Jws
    destroy loo_Jws2
    return
end if

// If we get here, the signature was validated..
Write-Debug "Signature validated."

// Recover the original content:
Write-Debug loo_Jws2.GetPayload("utf-8")

// Examine the protected header:
loo_JoseHeader = loo_Jws2.GetProtectedHeader(li_SignatureIndex)
if loo_Jws2.LastMethodSuccess <> 1 then
    Write-Debug "No protected header found at the given index."
    destroy loo_SbJwk
    destroy loo_RsaKey
    destroy loo_JwsProtHdr
    destroy loo_Jws
    destroy loo_Jws2
    return
end if

loo_JoseHeader.EmitCompact = 0

Write-Debug "Protected (JOSE) header:"
Write-Debug loo_JoseHeader.Emit()
destroy loo_JoseHeader

// Output:

// 	Signature validated.
// 	In our village, folks say God crumbles up the old moon into stars.
// 	Protected (JOSE) header:
// 	{ 
// 	  "alg": "PS256"
// 	}


destroy loo_SbJwk
destroy loo_RsaKey
destroy loo_JwsProtHdr
destroy loo_Jws
destroy loo_Jws2