RFR: 8245527: LDAP Cnannel Binding support for Java GSS/Kerberos

[Sean Mullan]

(resending to all lists on the review)

I'm just catching up a bit on this review.

Sorry if this has mentioned before, but are you planning to write a CSR 
and release note? I think this is needed for the 
com.sun.jndi.ldap.tls.cbtype property. I'm also wondering if this 
property should be documented in the javadocs, and why it is not a 
standard property (i.e. "java.naming.ldap.tls.cbtype").

I was also wondering what relation this has to the "G2" standard SASL 
mechanisms defined in RFC 5801 [1], and whether that is something we 
should be using to negotiate this channel binding, and if not, why not. 
Or if this is something that is implementation-specific and will only 
work with Microsoft LDAP technology, in which case, we might want to 
make that more explicit, perhaps by including "microsoft" or something 
like that in the property name.

Thanks,
Sean

[1] https://tools.ietf.org/html/rfc5801

On 6/8/20 9:07 AM, Aleks Efimov wrote:
> Hi Alexey,
> 
> I've looked through LdapCtx/LdapClient/SaslBind changes:
> 
> Do we need to check if CHANNEL_BINDING is set explicitly for all 
> connection types? Maybe we can move the check inside 'if (conn.sock 
> instanceof SSLSocket) {' block.
> 
> Also, instead of setting CHANNEL_BINDING in context environment and then 
> removing it in finally block, it would be better to clone the 
> environment, put calculated CHANNEL_BINDING into it, and pass the cloned 
> one to Sasl.createSaslClient.
> 
> Another suggestion about the code that verifies if both properties are 
> set before connection is started:
> As you've already mentioned the new code in LdapCtx is only needed for 
> checking if timeout is set. Could we try to remove LdapCtx::cbType field 
> and all related methods from LdapCtx (this class is already 
> over-complicated and hard to read) and replace it with some static 
> method in LdapSasl? It will help to localize all changes to LdapSasl 
> except for one line in LdapCtx.
> 
> I mean something like this:
> Replace
> +
> +            // verify LDAP channel binding property
> +            if (cbType != null && connectTimeout == -1)
> +                    throw new 
> NamingException(TlsChannelBinding.CHANNEL_BINDING_TYPE +
> +                            " property requires " +
> +                            CONNECT_TIMEOUT +
> +                            " property is set.");
> With
> + 
> LdapSasl.checkCbParameters((String)envprops.get(TlsChannelBinding.CHANNEL_BINDING_TYPE), 
> connectTimeout);
> 
> And add something like that to LdapSasl (or maybe pass the full env here):
> + public static void checkCbParameters(String cbTypePropertyValue, int 
> connectTimeout) throws NamingException {
> +     TlsChannelBindingType cbType = 
> TlsChannelBinding.parseType(cbTypePropertyValue);
> +     // verify LDAP channel binding property
> +     if (cbType != null && connectTimeout == -1) {
> +         throw new 
> NamingException(TlsChannelBinding.CHANNEL_BINDING_TYPE +
> +                 " property requires com.sun.jndi.ldap.connect.timeout" +
> +                 " property is set.");
> +     }
> + }
> 
> Other LdapCtx/LdapClient/SaslBind  changes look fine to me.
> 
> With Kind Regards,
> Aleksei
> 
> On 06/06/2020 20:45, Alexey Bakhtin wrote:
>> Hello Max, Daniel,
>>
>> Thank you for review.
>>
>> Please review new version of the patch :
>> http://cr.openjdk.java.net/~abakhtin/8245527/webrev.v5/
>>
>> In this version:
>> - TlsChannelBinding class is moved into the com.sun.jndi.ldap.sasl 
>> package
>> - SSL Ceritificate related code is moved from LdapClient  into the 
>> LdapSasl.saslBind method
>> - verification and removal of internal property is also moved to 
>> LdapSasl.saslBind method
>> - verification of connectTimeout property is moved to LdapCtx.connect. 
>> I’ve found that connectionTimeout could be assigned later then cbType
>>
>> The test for this issue is not ready yet. I did not find any suitable 
>> test case that can be reused.
>>
>> Thank you
>> Alexey
>>
>>> On 6 Jun 2020, at 09:44, Weijun Wang <weijun.wang at oracle.com> wrote:
>>>
>>>
>>>
>>>> On Jun 6, 2020, at 2:41 PM, Weijun Wang <weijun.wang at oracle.com> wrote:
>>>>
>>>>
>>>>
>>>>> On Jun 5, 2020, at 11:03 PM, Alexey Bakhtin <alexey at azul.com> wrote:
>>>>>
>>>>> Hello Max,
>>>>>
>>>>> Thank you a lot for review.
>>>>>
>>>>> Could you check the new version of the patch :
>>>>> http://cr.openjdk.java.net/~abakhtin/8245527/webrev.v4/
>>>>>
>>>>> I’ve made the following changes:
>>>>> - TlsChannelBinding class is moved to java.naming module.
>>>>> java.security.sasl module is not affected any more
>>>>> - I pass tlsCB.getData() directly to the SASL mechanism as you 
>>>>> suggested
>>>>> - I’ve made some guards to prevent application from using 
>>>>> "com.sun.security.sasl.tlschannelbinding” property directly:
>>>>>     - LdapClient verifies if internal property is not set
>>>> 245                     // Prepare TLS Channel Binding data
>>>> 246                     if (conn.sock instanceof SSLSocket) {
>>>> 247                         // Internal property cannot be set 
>>>> explicitly
>>>> 248                         if 
>>>> (env.get(TlsChannelBinding.CHANNEL_BINDING) != null) {
>>>> 249                             throw new 
>>>> NamingException(TlsChannelBinding.CHANNEL_BINDING +
>>>> 250                                     " property cannot be set 
>>>> explicitly");
>>>> 251                         }
>>>>
>>>> If not TLS, this property value be kept there and visible inside the 
>>>> SASL mech.
>>>>
>>>>>     - GssKrb5Client uses props.remove() to read and remove internal 
>>>>> property
>>> Maybe you can remove the value in LdapClient.java, in case the mech 
>>> used is not GSSAPI. You can remove it in a finally block after line 303.
>>>
>>> --Max
>>>
>>>> Traditionally, we use "com.sun..." name which is a JDK supported 
>>>> name (although not at Java SE level), you might want to use a name 
>>>> which is even more internal.
>>>>
>>>>
>>>> Thanks,
>>>> Max
>>>>
>>>> p.s. I see that NTLM also supports ChannelBinding. I'll see if I can 
>>>> improve the NTLM SASL mech to support it.
>