Android RSA key length

Question

I would like to generate and store securely a 4096 bit RSA key pair on an Android device running API 18+ (4.3). The documentation states the AndroidKeyStore supports 4096 bit keys on API 18. However there is no method/way for setting the key length using the KeyPairGeneratorSpec. The setKeyLength and the setAlgorithmParameterSpec are API 19+. Since the documentation claims that the 4096 key length is supported there has to be some way of setting that.

Tiffanietiffanle

The AndroidKeyStore always had more features than accessible through it's public API. See the blog post Credential storage enhancements in Android 4.3. – Tew

@Robert: That blog posts specifically says the keysize cannot be changed from the default of 2048. – Szabadka

any answer on this? – Curule