Tcl

Export a Private Key as a JWK

Demonstrates the Chilkat PrivateKey.GetJwk method, which exports the key as a compact JWK (JSON Web Key). It takes no arguments; binary values use Base64url without padding.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: JWK is the JSON key format used across modern web security — JWT, OAuth, OpenID Connect. Exporting to it lets you publish a key into a JWK Set or hand it to a web framework that speaks JWK. Note this is the private JWK: it includes the private parameters (d and, for RSA, the CRT values), so it is highly sensitive — publish only the public JWK derived from ToPublicKey when sharing.

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Tcl


load ./chilkat.dll

set success 0

#  Load a private key to export.
set privKey [new_CkPrivateKey]

set success [CkPrivateKey_LoadPemFile $privKey "qa_data/private.pem"]
if {$success == 0} then {
    puts [CkPrivateKey_lastErrorText $privKey]
    delete_CkPrivateKey $privKey
    exit
}

#  Export as a compact JWK (JSON Web Key).  Binary values use Base64url without padding.
set jwk [CkPrivateKey_getJwk $privKey]
if {[CkPrivateKey_get_LastMethodSuccess $privKey] == 0} then {
    puts [CkPrivateKey_lastErrorText $privKey]
    delete_CkPrivateKey $privKey
    exit
}

puts "$jwk"

delete_CkPrivateKey $privKey