On Tue, Jun 9, 2015 at 12:28 PM, Sangjin Lee <[email protected]> wrote:
> Thanks folks. I filed DIRSERVER-2071: > https://issues.apache.org/jira/browse/DIRSERVER-2071 > thanks for the bug report, I have committed the fix in trunk, would it be possible for you to give a try? > > Sangjin > > On Mon, Jun 8, 2015 at 8:16 PM, Kiran Ayyagari <[email protected]> > wrote: > >> Hi Sangjin, >> >> On Tue, Jun 9, 2015 at 6:45 AM, Sangjin Lee <[email protected]> wrote: >> >>> Hi, >>> >>> This might be a known issue, but I was not able to find discussions on >>> this anywhere... >>> >>> I stumbled on an interesting issue with kerberos authentication failure >>> with an Apache DS server while debugging a hadoop unit test failure. FYI, >>> hadoop is using Apache DS 1.0.0-M20 with Mina 2.0.0-M15. This problem is >>> happening on some machines but not on others. >>> >>> Basically, a kerberos message to the Apache DS server is failing with >>> the following exception: >>> 2015-06-08 20:35:57,189 ERROR KerberosProtocolHandler - /127.0.0.1:54477 >>> EXCEPTION >>> org.apache.mina.filter.codec.ProtocolDecoderException: >>> java.lang.NullPointerException: message (Hexdump: ...) >>> at >>> org.apache.mina.filter.codec.ProtocolCodecFilter.messageReceived(ProtocolCodecFilter.java:234) >>> at >>> org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434) >>> at >>> org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilterChain.java:48) >>> at >>> org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceived(DefaultIoFilterChain.java:802) >>> at >>> org.apache.mina.core.filterchain.IoFilterAdapter.messageReceived(IoFilterAdapter.java:120) >>> at >>> org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434) >>> at >>> org.apache.mina.core.filterchain.DefaultIoFilterChain.fireMessageReceived(DefaultIoFilterChain.java:426) >>> at >>> org.apache.mina.core.polling.AbstractPollingIoProcessor.read(AbstractPollingIoProcessor.java:604) >>> at >>> org.apache.mina.core.polling.AbstractPollingIoProcessor.process(AbstractPollingIoProcessor.java:564) >>> at >>> org.apache.mina.core.polling.AbstractPollingIoProcessor.process(AbstractPollingIoProcessor.java:553) >>> at >>> org.apache.mina.core.polling.AbstractPollingIoProcessor.access$400(AbstractPollingIoProcessor.java:57) >>> at >>> org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor.run(AbstractPollingIoProcessor.java:892) >>> at >>> org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:65) >>> at >>> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) >>> at >>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) >>> at java.lang.Thread.run(Thread.java:745) >>> Caused by: java.lang.NullPointerException: message >>> at >>> org.apache.mina.filter.codec.AbstractProtocolDecoderOutput.write(AbstractProtocolDecoderOutput.java:44) >>> at >>> org.apache.directory.server.kerberos.protocol.codec.MinaKerberosDecoder.decode(MinaKerberosDecoder.java:65) >>> at >>> org.apache.mina.filter.codec.ProtocolCodecFilter.messageReceived(ProtocolCodecFilter.java:224) >>> ... 15 more >>> >>> >>> I traced it down to a rather silent failure of Asn1Decoder. Basically >>> the ASN.1 decoder thinks the byte buffer it is passed does not have the >>> promised size payload and aborts parsing: >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - >>> >>>========================================== >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - --> Decoding a PDU >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - >>> >>>------------------------------------------ >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - --- State = TAG_STATE_START >>> --- >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x6C >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - Tag 0x6C has been decoded >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - --- State = >>> LENGTH_STATE_START --- >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x82 >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - --- State = >>> LENGTH_STATE_PENDING --- >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x02 >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x02 >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x41 >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - --- State = LENGTH_STATE_END >>> --- >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x30 >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - Parent length : TLV expected >>> length stack : - null >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - Root TLV[577] >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - Length 577 has been decoded >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - --- State = >>> VALUE_STATE_START --- >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - current byte : 0x30 >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - >>> <<<------------------------------------------ >>> 2015-06-08 20:35:57,187 DEBUG Asn1Decoder - <-- End decoding : TLV[ >>> 0x6C, 577, DATA[... ]] >>> >>> >>> Here's an interesting thing however. The reason the buffer has fewer >>> bytes than the length value indicates is that the TCP message is split into >>> 2 packets due to a small TCP window size on this problematic machine. For >>> the kerberos message of size 585 bytes, the first 570 bytes are sent in the >>> first packet, and the remaining 15 bytes in another packet. The Asn1Decoder >>> thinks that it is missing the last 15 bytes and aborts decoding it. >>> >>> Having small TCP window sizes aside, this strikes me as a code issue. >>> Shouldn't the server be able to handle the kerberos message even if it is >>> split into multiple packets? Is this a known issue with a >>> workaround/solution? >>> >>> I looked at MinaKerberosDecoder, and see it extend >>> ProtocolDecoderAdapter. But shouldn't it extend CumulativeProtocolDecoder >>> to be able to handle situations like this? >>> >> the current ASN.1 decoder is supposed to handle this case, can you file a >> bug, I will take a look >> >>> >>> Thanks in advance, >>> Sangjin >>> >> >> >> >> -- >> Kiran Ayyagari >> http://keydap.com >> > > -- Kiran Ayyagari http://keydap.com
