RFR 8205445: Add RSASSA-PSS Signature support to SunMSCAPI

Weijun Wang weijun.wang at oracle.com
Thu Jun 21 11:12:53 UTC 2018

Please take a review on this change

and the release note at


The code change adds RSASSA-PSS signature support to the SunMSCAPI provider.

Several notes:

1. CryptoAPI (which SunMSCAPI is based on and now a deprecated technology) does not support RSASSA-PSS. In fact, CNG [1] is used to perform the signing and verification. This is certainly not a perfect solution and we are thinking of support CNG in a more sophisticated way in future releases of JDK.

2. For unknown reason, the newly added verification code for RSASSA-PSS does not work correctly (precisely, ::NCryptTranslateHandle returns NTE_INVALID_PARAMETER). A fallback mechanism is added into mscapi/RSASignature.java. A SunRsaSign Signature object is actually used when a SunMSCAPI Signature is initialized to verify an RSASSA-PSS signature.

3. It looks like CNG only supports PSSParamterSpec with the same message hash algorithm and MGF1 hash algorithm, because there is only one algorithm field in BCRYPT_PSS_PADDING_INFO [2]. This is checked when setting the parameter.

4. It looks like CNG only supports RSASSA-PSS using these hash algorithms: SHA-1, SHA-256, SHA-384, and SHA-512. This is not checked at parameter setting but sign() will throw a SignatureException saying "Unrecognised hash algorithm". Since the verify() side uses a fallback SunRsaSign signature, other hash algorithms are supported.


[1] https://msdn.microsoft.com/en-us/library/windows/desktop/aa376210(v=vs.85).aspx
[2] https://msdn.microsoft.com/en-us/library/windows/desktop/aa375529(v=vs.85).aspx
[3] https://msdn.microsoft.com/en-us/library/windows/desktop/aa375534(v=vs.85).aspx

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