Tcl

Export an Encrypted PKCS #8 Private Key as Encoded Text

Demonstrates the Chilkat PrivateKey.GetPkcs8EncryptedENC method, which exports the key as password-protected PKCS #8 DER and encodes the encrypted DER as text. The first argument names the binary encoding and the second is the password. The cipher is selected by Pkcs8EncryptAlg.

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: This combines encryption with text encoding: the key is protected by a passphrase and returned as a string, ideal for storing an encrypted key in a text-only medium such as JSON or an environment variable. It is the encrypted counterpart to GetPkcs8ENC. Source the password securely.

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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
}

#  The key password is not hard-coded in a real application; obtain it from an interactive
#  prompt, environment variable, or a secrets vault.
set password "myKeyPassword"

#  Export as password-protected PKCS #8 DER, then encode the encrypted DER as text.  The 1st
#  argument names the binary encoding and the 2nd is the password.  The cipher is selected by the
#  Pkcs8EncryptAlg property.
set encoded [CkPrivateKey_getPkcs8EncryptedENC $privKey "base64" $password]
if {[CkPrivateKey_get_LastMethodSuccess $privKey] == 0} then {
    puts [CkPrivateKey_lastErrorText $privKey]
    delete_CkPrivateKey $privKey
    exit
}

puts "$encoded"

delete_CkPrivateKey $privKey