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Lianja

Convert RSA Private Key to Public Key

See more RSA Examples

Demonstrates how to get a public RSA key from a private RSA key.

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Lianja
llSuccess = .F.

loPrivKey = createobject("CkPrivateKey")

// Step 1: Load the private key from a source.
// (Chilkat can load private keys from all types of formats, and from in-memory bytes or encoded strings.
// see the online reference documentation for more options.)
llSuccess = loPrivKey.LoadPemFile("qa_data/pem/VP_Private.pem")
if (llSuccess = .F.) then
    ? loPrivKey.LastErrorText
    release loPrivKey
    return
endif

// Step 2: Get the public key object from the private key object.
loPubKey = createobject("CkPublicKey")
loPrivKey.ToPublicKey(loPubKey)

// Step 3: Save the public key in a desired format. 
// (Chilkat can load or save public and private keys in many different formats.  See
// the online reference documentation for more options.)

// Saves to a PKCS8 PEM file.
llBPreferPkcs1 = .F.
llSuccess = loPubKey.SavePemFile(llBPreferPkcs1,"qa_data/pem/VP_Public.pem")
if (loPubKey.LastMethodSuccess = .F.) then
    ? loPubKey.LastErrorText
    release loPrivKey
    release loPubKey
    return
endif

? "Extracted and saved public key from private key."


release loPrivKey
release loPubKey