Lianja Requires Chilkat v11.0.0+

RSA SHA256 Signature using Private Key from Java Keystore

See more RSA Examples

Signs plaintext using RSA SHA256 using a key from a Java keystore.

Duplicatest this code:

KeyStore keystore; // key repository for keys containing signature certificate
String alias; // alias for the certificate in the key repository
String password; // password for the certificate's private key
String plaintext; // text being signed


Signature signature = Signature.getInstance("SHA256withRSA");
signature.initSign((PrivateKey) keystore.getKey(alias, password.toCharArray()));
signature.update(plaintext.getBytes("UTF-8"));
byte[] rsa_text= signature.sign();

Lianja

llSuccess = .F.

//  This requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

loJks = createobject("CkJavaKeyStore")

lcJksPassword = "secret"

//  Load the Java keystore from a file.  The JKS file password is used
//  to verify the keyed digest that is found at the very end of the keystore.
//  It verifies that the keystore has not been modified.
llSuccess = loJks.LoadFile(lcJksPassword,"qa_data/jks/sample_secret.jks")
if (llSuccess = .F.) then
    ? loJks.LastErrorText
    release loJks
    return
endif

//  Get the private key from the JKS.
//  The private key password may be different than the file password.
lcPrivKeyPassword = "secret"
llCaseSensitive = .F.
loPrivKey = createobject("CkPrivateKey")
llSuccess = loJks.PrivateKeyOf(lcPrivKeyPassword,"some.alias",llCaseSensitive,loPrivKey)
if (llSuccess = .F.) then
    ? loJks.LastErrorText
    release loJks
    release loPrivKey
    return
endif

//  Establish the RSA object and tell it to use the private key..
loRsa = createobject("CkRsa")

llSuccess = loRsa.UsePrivateKey(loPrivKey)
if (llSuccess = .F.) then
    ? loRsa.LastErrorText
    release loJks
    release loPrivKey
    release loRsa
    return
endif

//  Indicate we'll be signing the utf-8 byte representation of the string..
loRsa.Charset = "utf-8"

//  Sign some plaintext using RSA-SHA256

lcPlaintext = "this is the text to be signed"
loBinarySignature = loRsa.SignString(lcPlaintext,"SHA256")
if (loRsa.LastMethodSuccess = .F.) then
    ? loRsa.LastErrorText
    release loJks
    release loPrivKey
    release loRsa
    return
endif

//  Alternatively, if the signature is desired in some encoded string form,
//  such as base64, base64-url, hex, etc.
loRsa.EncodingMode = "base64-url"
lcSignatureStr = loRsa.SignStringENC(lcPlaintext,"SHA256")
? "base64-url RSA signature: " + lcSignatureStr


release loJks
release loPrivKey
release loRsa