RFR: 8244336: Restrict algorithms at JCE layer

[Valerie Peng]

On Thu, 24 Jul 2025 21:36:58 GMT, Anthony Scarpino <ascarpino at openjdk.org> wrote:

>> This enhancement introduces a new security property "jdk.crypto.disabledAlgorithms" which can be leveraged to disable algorithms for JCE/JCA crypto services. For now, only Cipher, KeyStore, MessageDigest, and Signature services support this new security property. The support can be expanded later to cover more services if needed. Note that this security property is meant to disable algorithms irrespective of providers. If the algorithm is found to be disabled, it will be rejected before reaching out to provider(s) for the corresponding implementation(s).
>> 
>> A few implementation notes:
>> 1) The specified security property value is lazily loaded and all changes after it's been loaded are ignored. Invalid entries, e.g. wrong syntax, are ignored and removed. The algorithm name check is case-insensitive. If a disabled algorithm is known to has an object identifier (oid) by JDK, this oid and its aliases is also added to the disabled services.
>> 2) The algorithm name checking impl is based on the sun.security.util.AlgorithmConstraints class, but without the decomposing and different constraints.
>> 3) The hardwiring of NONEwithRSA signature to RSA/ECB/PKCS1Padding cipher in java.security.Signature class is removed. Instead, this is moved to the provider level, i.e. SunJCE and SunPKCS11 provider are changed to claim the NONEwithRSA signature support. Disabling one will not affect the other. 
>> 
>> CSR will be filed once the review is wrapping up.
>> 
>> Thanks~
>> Valerie
>
> src/java.base/share/classes/sun/security/util/KnownOIDs.java line 186:
> 
>> 184:     // RSASecurity
>> 185:     // PKCS1 1.2.840.113549.1.1.*
>> 186:     PKCS1("1.2.840.113549.1.1", "RSA", false), // RSA KeyPairGenerator and KeyFactory
> 
> With you specifying a new "RSA" stdName in the `RSA` enum, do we really need a `"RSA", false` here?  After doing an internet search on the OID, it looks like "PKCS-1" maybe more appropriate.

The reason for `"RSA", false` is because the `KnownOIDs.stdName()` is meant to return the user-friendly standard algorithm name and the crypto services using this PKCS1 OID is `RSA` KeyPairGenerator and KeyFactory. Existing regression test doesn't cover this particular scenario and I feel it's safer to not changing this unless it is known to cause a problem.

> src/java.base/share/conf/security/java.security line 775:
> 
>> 773: 
>> 774: #
>> 775: # Algorithm restrictions for Java Crypto API services
> 
> Since this is a title, an empty comment line between this and the start of the description would be appropriate.

Yes, I will add one.

> src/java.base/share/conf/security/java.security line 776:
> 
>> 774: #
>> 775: # Algorithm restrictions for Java Crypto API services
>> 776: # The syntax of the disabled services string is described as follows:
> 
> Before you get into the syntax, I think you should explain what the feature is and how it is triggered, such as, `getInstance()`.

Will do.

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PR Review Comment: https://git.openjdk.org/jdk/pull/26377#discussion_r2241443431
PR Review Comment: https://git.openjdk.org/jdk/pull/26377#discussion_r2241445300
PR Review Comment: https://git.openjdk.org/jdk/pull/26377#discussion_r2241446396