Code review request, 7106773: 512 bits RSA key cannot work with SHA384 and SHA512

Xuelei Fan xuelei.fan at oracle.com
Fri Nov 18 14:38:19 UTC 2011 

On 11/18/2011 10:16 PM, Weijun Wang wrote:
> 
> On 11/18/2011 08:39 PM, Xuelei Fan wrote:
>> The VPN is awesomely bad today.
>>
>> The webrev in cr.openjdk is
>> http://cr.openjdk.java.net/~xuelei/7106773/webrev.01/
>>
>> On 11/18/2011 7:39 PM, Weijun Wang wrote:
>>> Oh, there seems to be much more non-trivial code changes then the
>>> previous version of webrev.
>>>
>>> I now focus on the utility class KeyLength.java:
>>>
>>> In ReflectiveProvider, how about adding a "." at the end of package
>>> name?
>>>
>> It's safer.
>>
>>> Also, is the while loop really necessary in getKeyLengthMethod? Why not
>>> directly call getDeclaredMethod on the the baseClassName? If you want to
>>> make sure the current class is a subclass of the baseClassName, try
>>> isAssignableFrom.
>>>
>> It's a little strange of the implement of getKeyLengthMethod() because
>> of the following causes:
>> 1. Class.getDeclaredMethod() cannot return inherited methods.
>>
>> 2. Class.forName("sun.security.pkcs11.P11Key") is not reliable.
>>     The current class loader is not always able to find the P11Key class.
> 
> Oh, In which case?
> 
In the previous webrev, I found the case while running
test/sun/security/pkcs11/KeyStore/ClientAuth.java while call
Class.forName() with the current class loader.

>>   As you saw in the previous webrev, I specified the class loader while
>> searching for the class:
>>     Class.forName("sun.security.pkcs11.P11Key", true,
>>                        key.getClass().getClassLoader());
>>
>>     There is one assumption that every key will come from the same class
>> loader during the JVM life. So we can cache the loaded P11Key class.
>> It's a little risky.
>>
>>     And more, it's OK when there is only one PKCS11 provider.  However,
>> while we adding MSCAPI in, we will have to look through both PKCS11
>> provider and MSCAPI provider in order to select the proper cached key
>> class. If we get a key from none of PKCS11 and MSCAPI, we will continue
>> calling the Class.forName() repeatedly until we are able to encounter
>> the PKCS11 key or MSCAPI key. It's very bad in performance.
>>
>>     The calling in the getKeyLengthMethod() is lightweight, and we don't
>> have to worry about the class loader any more.
> 
> Calling getDeclaredMethod each time is a waste. How about just
> 
>         while (clazz != null) {
>             if (clazz.getName().equals(baseClassName)) {
>                 // do sth
>                 break;
>             }
>             clazz = clazz.getSuperclass();
>         }
> 
> Also, you're using methods in reflection. Is it faster to use fields?
> 
I also concerns about the override of the target method, although there
is no such override at present. From some reports, it seems that fields
reflection cost more cycles than method reflection.

Performance is a big issue here. What do you think if we change the get
key length method of pkcs11.P11Key and mscapi.Key for better performance?

Thanks,
Xuelei

> Thanks
> Max
> 
>>
>>> As for the test, I was thinking that you can add a unit test on the
>>> KeyLength class itself.
>>>
>> I may add some new and simple tests on KeyLength only.
>>
>> Thanks,
>> Xuelei
>>
>>> Thanks
>>> Max
>>>
>>>
>>> On 11/17/2011 11:14 PM, Xuelei Fan wrote:
>>>> Sean, could you also review the fix? I plan to backport the fix to JDK
>>>> 7, so that the key size constraints for both JSSE and CertPath can work
>>>> with PKCS11 and MSCPI.
>>>>
>>>> updated webrev:
>>>> http://javaweb.us.oracle.com/~xf138604/bugbios/7106773/webrev.01/
>>>>
>>>> In the new webrev, I add a new KeyLength class under sun.security.util.
>>>> I think it may be useful for other models.
>>>>
>>>> On 11/11/2011 2:33 PM, Weijun Wang wrote:
>>>>> SSLContextVersion.java:
>>>>>
>>>>>      typo: suported ->   supported
>>>>>
>>>> Updated.
>>>>
>>>>> DisabledAlgorithmConstraints.java:
>>>>>
>>>>>      When can size == 0? Why it's not allowed?
>>>>>
>>>> It's a line of dummy code in case the get key size method return 0.
>>>>
>>>>>      Yes, I think the reflection calls should be wrapped in doPriv
>>>>>
>>>>>      Please also consider keys from MSCAPI
>>>>>
>>>> Support MSCAPI now.
>>>>
>>>>>      Try looking at sun.misc.SharedSecrets and see if it's better
>>>>>      for you. Probably not. That class is used to share non-public
>>>>>      methods in public classes. Not the same case here.
>>>>>
>>>>> SignatureAndHashAlgorithm.java:
>>>>>
>>>>>      Is it possible to combine expected and signingKey into a single
>>>>>      signingKey? Of course that means it might need to be never null
>>>>>      and all key alg call it in a consistent way. I wonder if this
>>>>>      is OK for you.
>>>>>
>>>> It not always work. For example, the key algorithm may be "EC", but the
>>>> expected algorithm may be "ECDSA".
>>>>
>>>>>      The RSAKey interface seems not used anywhere.
>>>>>
>>>> Yes, removed.
>>>>
>>>>>      How about changing
>>>>>
>>>>>       288 }   // Otherwise, cannot determine the key size, prefer the
>>>>> most
>>>>>       289     // perferable hash algorithm.
>>>>>
>>>>>      to
>>>>>
>>>>>       maxDigestLength = Integer.MAX_VALUE;
>>>>>
>>>>>      then you don't need to assign -1 and check for<   0 later.
>>>>>
>>>> Good point.
>>>>
>>>>>      I would be glad if lines 302-306 can be further indented 4 spaces
>>>>>
>>>>>      The comment on lines 268-273 is confusing, because you did
>>>>> calculate
>>>>>      maxDigestAlgorithm for 512 bits key later.
>>>>>
>>>>>      Personally, I prefer comments on 274-281 and codes on 284-288
>>>>>      to be from a smaller keySize to bigger ones, but everything is
>>>>> OK.
>>>>>
>>>> Updated.
>>>>
>>>>> Test:
>>>>>
>>>>>      I would like a unit test on
>>>>> DisabledAlgorithmConstraints::getKeySize.
>>>>>      Hopefully the test can cover all SecretKey and PrivateKey from
>>>>> all
>>>>>      providers with all keysizes.
>>>>>
>>>> Added some new tests for PKCS11 and MSCAPI.
>>>>
>>>> Thanks,
>>>> Xuelei
>>>>
>>>>> Thanks
>>>>> Max
>>>>>
>>>>> On 11/11/2011 01:09 PM, Xuelei Fan wrote:
>>>>>> Hi Weijun,
>>>>>>
>>>>>> Are you available to review my fix for CR 7106773? The fix in JSSE
>>>>>> part
>>>>>> is straightforward in that the call to
>>>>>> SignatureAndHashAlgorithm.getPreferableAlgorithm() needs an
>>>>>> additional
>>>>>> Key parameter for RSA key exchanges. The significant change is at
>>>>>> sun/security/util/DisabledAlgorithmConstraints.java. I modified the
>>>>>> code
>>>>>> in order to get the key size of the unextractable key in PKCS#11
>>>>>> device.
>>>>>>
>>>>>> webrev: http://cr.openjdk.java.net/~xuelei/7106773/webrev.00/
>>>>>>
>>>>>> Thanks,
>>>>>> Xuelei
>>>>
>>

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