Code review request, 8028518, Increase the priorities of GCM cipher suites

Bradford Wetmore bradford.wetmore at oracle.com
Fri Jan 3 18:47:29 PST 2014



On 1/3/2014 6:19 PM, Xuelei Fan wrote:
> On 1/4/2014 6:41 AM, Bradford Wetmore wrote:
>> Looks ok to me, with the exception as you pointed out that this doesn't
>> follow section 4 of RFC 6460.
> Sorry, I did not get it.  Would you mind point out the line number of
> the concern?

This section in RFC 6460:

    A Suite B TLS client configured at a minimum level of security of 128
    bits MUST offer the TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 or the
    TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 cipher suite in the
    ClientHello message.  The TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
    cipher suite is preferred; if offered, it MUST appear before the
    TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 cipher suite.

You have:

993  add("TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
...
995  add("TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",

>>  Why was this done, and how did you
>> originally determine the original ciphersuite ordering for GCMs?
>>
> Per RFC 6460, there are two profiles, "Suite B Combination 1" and "Suite
> B Combination 2".  SunJSSE default cipher suite preference does not
> compliant to the profiles at present.  That's why it is said,
> "The preference order of the GCM cipher suites does not follow the spec
> of RFC 6460."
>
> About the ordering, please refer to line 964-977 of CipherSuite.java

My question was, how did you choose the current order (currently lines 
1080-1110:

TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
TLS_RSA_WITH_AES_256_GCM_SHA384
TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384
TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384
TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
TLS_DHE_DSS_WITH_AES_256_GCM_SHA384
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
TLS_RSA_WITH_AES_128_GCM_SHA256
TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256
TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256
TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
TLS_DHE_DSS_WITH_AES_128_GCM_SHA256

Brad


> Thanks,
> Xuelei
>
>> Brad
>>
>>
>> On 12/29/2013 7:56 PM, Xuelei Fan wrote:
>>> Hi,
>>>
>>> Please review this small update.
>>>
>>> webrev: http://cr.openjdk.java.net/~xuelei/8028518/webrev.00/
>>>
>>> In TLS protocols, cipher suite specifies the crypto algorithms used in
>>> TLS connections.  The priorities of cipher suites define the preference
>>> order that a cipher suite may be used in a TLS connection.
>>>
>>> When introducing the AEAD/GCM cipher suites in SunJSSE provider (JEP
>>> 115)[1], for better compatibility and interoperability, we decided to
>>> decrease the priority of cipher suites in GCM mode for a while before
>>> GCM technologies mature in the industry.
>>>
>>> It's time to consider to increase the priorities of GCM mode cipher
>>> suite in early stage of JDK 9.
>>>
>>> Thanks,
>>> Xuelei
>>>
>>> [1] http://openjdk.java.net/jeps/115
>


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