RSASSA-PSS key pairs do not expose PSS params via RSAKey.getParams()

[MarkAtwood]

Summary

KeyPairGenerator for RSASSA-PSS ignores the AlgorithmParameterSpec embedded in RSAKeyGenParameterSpec.getKeyParams() (Java 11+). The generated public key's getParams() returns null instead of the PSS parameters the key was generated with.

Expected behavior (per Java spec)

java.security.interfaces.RSAKey.getParams() (Java 11+) should return the PSSParameterSpec for RSASSA-PSS keys. This is how a verifier obtains the correct hash algorithm and salt length from the key, avoiding the need for out-of-band parameter negotiation.

Impact

The following idiomatic verification pattern fails with wolfJCE:

verifier.initVerify(pub);
verifier.setParameter(pub.getParams());  // returns null → hash never initialized
verifier.update(msg);
verifier.verify(sig);  // throws "Parameters must be set before updating with RSASSA-PSS"

Additionally, Signature.initVerify(pub) cannot auto-initialize PSS parameters from the key, so callers must always call setParameter explicitly with externally-obtained params.

Fix

• In WolfCryptKeyPairGenerator.initialize(), store RSAKeyGenParameterSpec.getKeyParams() when generating RSASSA-PSS keys.
• Wrap the generated public key so getParams() returns the stored PSSParameterSpec.
• In WolfCryptSignature.engineInitVerify(), if the padding is WC_RSA_PSS and the public key returns a PSSParameterSpec from getParams(), use it to initialize the digest automatically.

Discovered by

Wycheproof RsaPssTest.testSignVerifyWithParameters, testEncodeDecodePublic, testEncodeDecodePublicWithParameters.