Code review request, 8028518, Increase the priorities of GCM cipher suites
Xuelei Fan
Xuelei.Fan at Oracle.COM
Sat Jan 4 02:58:43 UTC 2014
On 1/4/2014 10:47 AM, Bradford Wetmore wrote:
>
>
> 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.
>
Understand. Do you note the circumstance of this spec, at the "level of
security of 128 bits"? In the next paragraph, it also talks about "
level of security of 192 bits".
If configured at a minimum level of security of 192 bits, the client
MUST offer the TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 cipher suite
and MUST NOT offer the TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 cipher
suite.
That's also one point I said that the preference are not RFC 6460
compliant at present. We may make improvement in the future.
> 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
I think except the above two cipher suites, the order of the following
cipher suites still adhere to the rules described in line 964-977. Right?
Thanks,
Xuelei
> 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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