(PureBasic) Compute JWK Thumbprint for RSA and EC Private Keys

Demonstrates how to compute a JSON Web Key thumbprint for a private key (RSA or ECC).

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

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkStringBuilder.pb"
IncludeFile "CkPrivateKey.pb"

Procedure ChilkatExample()

    privKey.i = CkPrivateKey::ckCreate()
    If privKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; A private key can be loaded from any format (binary DER, PEM, etc.)
    ; This example will load the private keys from PEM format, 
    ; and will then compute the JWK thumbprint.

    ; First do it for this RSA private key...

    sbPem.i = CkStringBuilder::ckCreate()
    If sbPem.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    bCrlf.i = 1
    CkStringBuilder::ckAppendLine(sbPem,"-----BEGIN RSA PRIVATE KEY-----",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"Proc-Type: 4,ENCRYPTED",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"DEK-Info: DES-EDE3-CBC,2E65118E6C7B5207",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"7cYUTW4ZBdmVZ4ILB08hcTdm5ib0E0zcy+I7pHpNQfJHtI7BJ4omys5S19ufJPBJ",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"IzYjeO7oTVqI37F6EUmjZqG4WVE2UQbQDkosZbZN82O4Ipu1lFAPEbwjqePMKufz",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"snSQHKfnbyyDPEVNlJbs19NXC8v6g+pQay5rH/I6N2iBxgsTmuemZ54EhNQMZyEN",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"R/CiheArWEH9H8/4hd2gc9Tb2s0MwGHILL4kbbNm5tp3xw4ik7OYWNrj3m+nG6Xb",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"vKXh2xEanAZAyMXTqDJTHdn7/CEqusQPJjZGV+Mf1kjKu7p4qcXFnIXP5ILnTW7b",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"lHoWC4eweDzKOMRzXmbABEVSUvx2SmPl4TcoC5L1SCAHEmZaKbaY7S5l53u6gl0f",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"ULuQbt7Hr3THznlNFKkGT1/yVNt2QOm1emZd55LaNe8E7XsNSlhl0grYQ+Ue8Jba",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"x85OapltVjxM9wVCwbgFyi04ihdKHo9e+uYKeTGKv0hU5O7HEH1ev6t/s2u/UG6h",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"TqEsYrVp0CMHpt5uAF6nZyK6GZ/CHTxh/rz1hADMofem59+e6tVtjnPGA3EjnJT8",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"BMOw/D2QIDxjxj2GUzz+YJp50ENhWrL9oSDkG2nzv4NVL77QIy+T/2/f4PgokUDO",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"QJjIfxPWE40cHGHpnQtZvEPoxP0H3T0YhmEVwuJxX3uaWOY/8Fa1c7Ln0SwWdfV5",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"gYvJV8o6c3sumcq1O3agPDlHC5O4IxG7AZQ8CHRDyASogzfkY6P579ZOGYaO4al7",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"WA1YIpsHs3/1f4SByMuWe0NVkFfvXckjpqGrBQpTmqQzk6baa0VQ0cwU3XlkwHac",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"WB/fQ4jylwFzZDcp5JAo53n6aU72zgNvDlGTNKwdXXZI5U3JPocH0AiZgFFWYJLd",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"63PJLDnjyE3i6XMVlxifXKkXVv0RYSz+ByS7Oz9aCgnQhNU8ycv+UxtfkPQih5zE",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"/0Y2EEFknajmFJpNXczzF8OEzaswmR0AOjcCiklZKRf61rf5faJxJhhqKEEBJuL6",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"oodDVRk3OGU1yQSBazT8nK3V+e6FMo3tWkra2BXFCD+pKxTy014Cp59S1w6F1Fjt",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"WX7eMWSLWfQ56j2kLMBHq5gb2arqlqH3fsYOTD3TNjCYF3Sgx309kVPuOK5vw61P",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"pnL/LN3iGY42WR+9lfAyNN2qj9zvwKwscyYs5+DPQoPmcPcVGc3v/u66bLcOGbEU",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"OlGa/6gdD4GCp5E4fP/7GbnEY/PW2abquFhGB+pVdl3/4+1U/8kItlfWNZoG4FhE",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"gjMd7glmrdFiNJFFpf5ks1lVXGqJ4mZxqtEZrxUEwciZjm4V27a+E2KyV9NnksZ6",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"xF4tGPKIPsvNTV5o8ZqjiacxgbYmr2ywqDXKCgpU/RWSh1sLapqSQqbH/w0MquUj",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"VhVX0RMYH/foKtjagZf/KO1/mnCITl86treIdachGgR4wr/qqMjrpPUaPLCRY3JQ",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"00XUP1Mu6YPE0SnMYAVxZheqKHly3a1pg4Xp7YWlM671oUORs3+VENfnbIxgr+2D",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"TiJT9PxwpfK53Oh7RBSWHJZRuAdLUXE8DG+bl0N/QkJM6pFUxTI1AQ==",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"-----END RSA PRIVATE KEY-----",bCrlf)

    ; The actual password for the above PEM is "passwd".
    success.i = CkPrivateKey::ckLoadEncryptedPem(privKey,CkStringBuilder::ckGetAsString(sbPem),"passwd")
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)
        CkStringBuilder::ckDispose(sbPem)
        ProcedureReturn
    EndIf

    ; Generate the JWK thumbprint:
    Debug "JWK thumbprint: " + CkPrivateKey::ckGetJwkThumbprint(privKey,"SHA256")

    ; Output:
    ; JWK thumbprint: QzUpUAW1Y5iksGxq3r1o3JMROR6D7FLwvRlHmDQVg0I

    ; --------------------------------------------------------------
    ; Now let's do an EC private key.  The following is an unencrypted PEM containing a 384-bit EC key..
    CkStringBuilder::ckClear(sbPem)
    CkStringBuilder::ckAppendLine(sbPem,"-----BEGIN PRIVATE KEY-----",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"MIG2AgEAMBAGByqGSM49AgEGBSuBBAAiBIGeMIGbAgEBBDAamStb0Xep3y3sWw2u",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"SSAdUPkgQ9Rvhlnx8XEVOYy2teh69T0on77ja02m03n8t8WhZANiAARUNSar38Rz",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"lKPyZFsNSGUanzpNRth0C+MikVEH8FAlDHMMpAs34dyF4IK0uxgbiEe9bQ+ieLrl",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"6xwFR0yaTivuwoyXC+ScGUnwnpaXmid6UUgw4ypbneHsaKuZ9JLdMAo=",bCrlf)
    CkStringBuilder::ckAppendLine(sbPem,"-----END PRIVATE KEY-----",bCrlf)

    success = CkPrivateKey::ckLoadPem(privKey,CkStringBuilder::ckGetAsString(sbPem))
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)
        CkStringBuilder::ckDispose(sbPem)
        ProcedureReturn
    EndIf

    ; Generate the JWK thumbprint:
    Debug "JWK thumbprint: " + CkPrivateKey::ckGetJwkThumbprint(privKey,"SHA256")

    ; Output:
    ; JWK thumbprint: ABAUUfNSONFsZYvZ_o_0bsPT3qeG3jttXB09VC_ETWQ


    CkPrivateKey::ckDispose(privKey)
    CkStringBuilder::ckDispose(sbPem)


    ProcedureReturn
EndProcedure