I am trying to generate a signature in RS256 algorithm using CrypterObject’s SHA and AsymmetricSign functions, following Scenario 2 on this article:
https://community.appeon.com/index.php/articles-blogs/tutorials-articles/2-powerbuilder/244-rest-enhancements-in-powerbuilder-2019
The private key is a 2048-bit key generated from an external source (openssl) and then converted to PKCS#8 format.
PB is able to generate the signature without any errors but the signature seems to be incorrect.
It could not be verified using the public key that was generated from the private key, and i have compared the PB-generated signature with an online tool and the two are different (the online tool signature can be verified by the public key so I can say it is correct).
Below is my script to generate the signature. Are there any missing/incorrect steps?
String ls_private_key_pkcs8, ls_sign
Blob lblb_private_key, lblb_hash, lblb_sign
CrypterObject lnv_CrypterObject
CoderObject lnv_CoderObject
lnv_CrypterObject = Create CrypterObject
lnv_CoderObject = Create CoderObject
ls_private_key_pkcs8 = 'MIIEvwIBADANBgkqhkiG9w0BAQEFAASCBKkwggSlAgEAAoIBAQCqEiwSEtzizwHq'
ls_private_key_pkcs8 += 'swCj+Y3DixlEjSvXya2/R9ftZBO5sPaOxDQP/YzZZqBjRpl6h6JyKh1fvtjidFPU'
ls_private_key_pkcs8 += 'zGLv1lQGzbZ3AHlOI09Dh4u2efuCFTcQfi9c8u6LkkQ4Ot0Bwv/mqSKBRthEXlEV'
...
...
...
lblb_private_key = lnv_CoderObject.Base64Decode(ls_private_key_pkcs8)
lblb_hash = lnv_CrypterObject.SHA(SHA256!, Blob('Key=Value', EncodingUTF8!))
lblb_sign = lnv_CrypterObject.AsymmetricSign(RSA!, lblb_hash, lblb_private_key)
ls_sign = lnv_CoderObject.Base64Encode(lblb_sign) //
