[RFR] 8160768: Add capability to custom resolve host/domain names within the default JDNI LDAP provider

[Daniel Fuchs]

Hi Rob,

LdapCtxFactory.java

  187             for (String u : r.getEndpoints()) {
  188                 try {
  189                     ctx = getLdapCtxFromUrl(
  190                             r.getDomainName(), new LdapURL(u), env);
  191                 } catch (NamingException e) {
  192                     // try the next element
  193                     lastException = e;
  194                 }
  195             }

is a break statement missing after line 190?

If not then can you add a comment explaining why only the last
context is retained (and returned?)

Alternatively, if a break is indeed missing, these three lines
could be moved into the for loop above:

  206             // Record the URL that created the context
  207             ctx.setProviderUrl(url);
  208             return ctx;

and maybe lines 206-207 could be moved into the
getLdapCtxFromUrl() method?

LdapDnsProviderService.java:

Why is this class non final? If it can be made final then
the protected methods should probably become package.

LdapDnsProvider.java:

It is strange to see new APIs with Hashtable in the method
signature. I understand that our implementation will need
an Hashtable at some point to call javax.naming.spi.NamingProvider,
but how likely is it that a clean room implementation of
a LdapDnsProvider will need to do that?

Maybe we could have Map<?,?> in the signature instead - and
leave the burden to our implementation - somewhere in ServiceLocator,
to adapt back to Hashtable where it needs to?


best regards,

-- daniel


On 25/10/2018 17:34, Rob McKenna wrote:
> This recently received CSR approval, so it seems like a good time to pick
> the codereview up again:
> 
> http://cr.openjdk.java.net/~robm/8160768/webrev.08/
> 
> Referencing:
> 
> http://mail.openjdk.java.net/pipermail/core-libs-dev/2017-December/050794.html
> 
> 1) I'm copying the behaviour from
> LdapCtxFactory.getInitialContext(Hashtable<?,?>) where an empty String is
> the default value used when the provider url is null.
> 
> I don't think HostnameChecker (by way of SNIHostname) will accept either
> empty or null values when doing the comparison.
> 
> Somewhat oddly however, LdapCtx.extendedOperation(ExtendedRequest)
> appears to pass the String "null" to
> StartTlsResponseImpl.setConnection(Connection, String), which attempts
> to substitute null values with the Connections host so there may be a bug
> here.
> 
> I'm happy to allow null returns here if necessary. Sean, can you
> comment on the distinction between null & "" as far as hostname
> verification is concerned?
> 
> 2) In the latest iteration lookupEndpoints() returns an
> Optional<LdapDnsResult>. Currently neither getEndpoints() nor
> getDomainName() can be null. (they can be an empty list and/or an empty
> String however)
> 
> 3) Corrected.
> 
> 4) See https://www.oracle.com/technetwork/java/seccodeguide-139067.html#4-5
> 
>      -Rob
>