(Tcl) Generate an RSA Key and Get as Base64 DER

Demonstrates how to generate a 2048-bit RSA key and return the public and private parts as unencrypted Base64 encoded DER.

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load ./chilkat.dll

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

set rsa [new_CkRsa]

# Generate a 2048-bit key.  Chilkat RSA supports
set success [CkRsa_GenerateKey $rsa 2048]
if {[expr $success != 1]} then {
    puts [CkRsa_lastErrorText $rsa]
    delete_CkRsa $rsa
    exit
}

# Get the public part of the key.
# pubKey is a CkPublicKey
set pubKey [CkRsa_ExportPublicKeyObj $rsa]

# There are two possible formats for representing the RSA public key 
# in ASN.1 (DER).  The possible formats are PKCS1 and PKCS8.
# We can get either by setting bChoosePkcs1 to 1 or 0.
set bChoosePkcs1 1
set pubKeyBase64Der [CkPublicKey_getEncoded $pubKey $bChoosePkcs1 "base64"]
puts "Public Key Base64 DER:"
puts "$pubKeyBase64Der"

delete_CkPublicKey $pubKey

# Now get the private key as Base64 DER:
# Get the private part of the key.
# (Note: A public key is actually just a subset of the private key.  
#  If you have the private key, you also have the public key.
#  Thus Chilkat provides a method to get the public key from the private key.)
# privKey is a CkPrivateKey
set privKey [CkRsa_ExportPrivateKeyObj $rsa]

# Again, we can get PKCS1 or PKCS8, but with different methods:
set privKeyPkcs1 [CkPrivateKey_getPkcs1ENC $privKey "base64"]
puts "Private Key PKCS1 Base64 DER:"
puts "$privKeyPkcs1"

set privKeyPkcs8 [CkPrivateKey_getPkcs8ENC $privKey "base64"]
puts "Private Key PKCS8 Base64 DER:"
puts "$privKeyPkcs8"

delete_CkPrivateKey $privKey


delete_CkRsa $rsa