On 26/07/2023 21:53, Christopher Schultz wrote:
Mark,On 7/26/23 13:58, Mark Thomas wrote:I'm not a huge fan of this feature in general. I prefer supporting features backed by specifications rather than vendor specific hacks.I think the PROXY protocol is fairly standard, even if it's not backed by an RFC. It's published by haproxy, but supported by nginx, (obviously) haproxy, AWS, httpd[1], and a whole bunch of others (https://www.haproxy.com/blog/use-the-proxy-protocol-to-preserve-a-clients-ip-address).
ACK. That reduces my concerns somewhat.
Well, the reality is that people want to use this in the real world and this is essentially the only way to do it, barring coming up with a whole new protocol for the purpose (I'm looking at /you/ AJP!).
Indeed.
So why not use /the/ protocol that (a) exists and (b) is supported by every single product that currently supports this type of thing?My support for any patch is going to depend on the specifics of the patch.In addition to the comments in the BZ - exposing the data as a request attribute is inconsistent with other mechanisms that solve the same problem (e.g. see RemoteIpFilter)+1The whole point of PROXY is to kind of mix-together the capabilities of both the RemoteIPFilter/Valve (which uses HTTP headers for source-information) and the top-level idea of a Connector (something that binds to a socket and pushes bytes around).The confusing thing here is that those two jobs are performed at relatively different levels in Tomcat at the moment, as I understand things.
Yes and no. RemoteIP[Filter|Valve] insert/modify the data at a higher level because that is where they sit but the data originates from the SocketWrapper.
If some kind of UberConnector could be built which essentially does
something like the following, it would be ideal:
public void accept(Socket s) {
ProxyHeader proxyHeader = readProxyHeader(s);
Connector realConnector = getRealConnector();
realConnector.setRemoteIP(proxyHeader.getRemoteIP());
realConnector.setRemotePort(proxyHeader.getRemotePort());
realConnector.takeItAway(s);
}
I'm sure there are other pieces of information that would be good to
pass-through, but the identity of the remote client is the most
interesting one.
Yes, that is the general idea. Just a couple of minor tweaks to use the SocketWrapper rather than the Connector and to do it in a slightly different place. The Acceptor is too early as we want to do as little as possible on the Acceptor thread.
- needs to be implemented for all ConnectorsI hope not. The connectors should be able to just have a thin layer in front of them "sipping" the header off the beginning of the connection. I am *way* out of my depth here when it comes to Tomcat internals and so I don't want to appear to be telling you (Mark) "how it works/should work", but conceptually it "seems easy". That may not translate into "easy implementation" or it may mean "tons of refactoring that we wouldn't need if we didn't care that much."
My point was that the provided patch only implements this for NIO. It needs to implement it for NIO2 as well. APR/Native looks to be a lot more difficult to implement and I'd be happy not implementing it for APR/Native.
- I'd expect it to look more like the SNI processingSNI processing is very connector-dependent, of course, because it's HTTPS-only. PROXY should allow HTTP, HTTPS, AJP, SFTP, JDBC, anything. So if it can be implemented as something that can just "sit in front of" *any* connector now or in the future of Tomcat, that would be ideal. It could definitely be implemented as an "optional feature" on a Connector-by-Connector basis, but my sense is that it can be done separately and globally.
Ah. You are thinking Connector as in protocol (HTTP, AJP, etc) whereas I am thinking in terms of implementation (NIO, NIO2, etc).
SNI is handled independently of implementation and I think PROXY should be handled the same way. They also sit at almost the same point in the processing (PROXY needs to be first). PROXY parsing could be implemented within the existing handshake() method but I think it would be much cleaner in a separate method.
Without looking at it too closely I think the implementation would look something like:
- a new method on SocketWrapperBase that
- checks if PROXY is enabled
- returns immediately if PROXY is not enabled or has already
been parsed
- uses a new utility class (or classes) to parse the header
(reading via the read() methods on SocketWrapperBase)
- sets the cached values for remoteAddr, remoteHost,
remotePort etc
- The SocketProcessor.doRun() implementations add a call to this new
method just before the TLS handshake
If we want to support the TLS information then a little additional
refactoring will be required (probably to cache the result of
SocketWrapperBase.getSslSupport) so the new utility classes can insert a
PROXY specific SSLSupport implementation.
Again, I'm speaking from a position of profound ignorance, here. Please don't hear me say "oh, this is easy, Mark... just go do it!" :)
:)Actually with the patch that has already been provided and the suggested implementation outline above I don't think there is too much work to do.
Generally, I don't think implementing this is going to be possible as some sort of plug-in.+1 Unless the plug-in is "a whole new set of protocol/endpoint/etc. handlers" which is a rather serious commitment.
On reflection, with the approach above we probably could implement this via a new plug-in framework but I am not sure it is worth the effort at this point. Something to keep in mind if we have more things wanting to integrate at this point in the processing chain.
Mark
-chris[1] https://httpd.apache.org/docs/2.4/mod/mod_remoteip.html search for "haproxy"On 26/07/2023 17:44, Amit Pande wrote:Missed to ask this: Looking the patch, it involves modifying Tomcat code.Was wondering if it would be possible to refactor this patch and/or allow Tomcat core code to extend and plug-in the proxy protocol support?Thanks, Amit -----Original Message----- From: Amit Pande Sent: Wednesday, July 26, 2023 11:43 AM To: Tomcat Users List <users@tomcat.apache.org> Subject: RE: [External] Re: Supporting Proxy Protocol in Tomcat Chris, Mark, Any thoughts on this?Mark, if we clean up the patch and re-submit, do you will have any concerns (specially security wise)?Thanks, Amit -----Original Message----- From: Jonathan S. Fisher <exabr...@gmail.com> Sent: Monday, July 24, 2023 12:41 PM To: Tomcat Users List <users@tomcat.apache.org> Subject: Re: [External] Re: Supporting Proxy Protocol in Tomcat Just a side note, because we're also very interested in this patch!Awhile back, I was successfully able to apply this patch and terminate TCP/TLS using HaProxy. We then had Tomcat listen on a unix domain socket and the Proxy protocol provided *most *of the relevant/required information to tomcat. I believe we had to add a Valve to tomcat to set the Remote IP however as the patch didn't handle that case.I can find my notes from that experiment, but I do remember getting a significant boost in throughput and decrease in latency.+1 for this patch and willing to help out!On Mon, Jul 24, 2023 at 11:22 AM Amit Pande <amit.pa...@veritas.com.invalid>wrote:Thank you, Chris, again for inputs. And sorry to circle back on this, late. One related question is - does it make sense to use the patch attached in https://bz.apache.org/bugzilla/show_bug.cgi?id=57830 ? And potentially, get it integrated into Tomcat versions? There are concerns from Mark about using the patch in its current state, but I see last comment (#24) on the issue and looks like there are some more points to be concluded. Thanks, Amit -----Original Message----- From: Christopher Schultz <ch...@christopherschultz.net> Sent: Wednesday, May 10, 2023 4:21 PM To: users@tomcat.apache.org Subject: Re: [External] Re: Supporting Proxy Protocol in Tomcat Amit, On 5/10/23 12:59, Amit Pande wrote:Yes, we intended to have Tomcat run behind a (transparent) TCP proxy e.g.https://www/. envoyproxy.io%2Fdocs%2Fenvoy%2Flatest%2Fintro%2Farch_overview%2Fother_ features%2Fip_transparency&data=05%7C01%7CAmit.Pande%40veritas.com%7Ca 85e610757b348137b4008db8c6d8156%7Cfc8e13c0422c4c55b3eaca318e6cac32%7C0 %7C0%7C638258174209955308%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAi LCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=W NEV4UQ5q4Nl8SEFHMz7C%2Fj3Qr7pCHpfyvQLeBn56uQ%3D&reserved=0 which supports the proxy protocol.Since there is not much action on thishttps://bz.a/ pache.org%2Fbugzilla%2Fshow_bug.cgi%3Fid%3D57830&data=05%7C01%7CAmit.Pande%40veritas.com%7Ca85e610757b348137b4008db8c6d8156%7Cfc8e13c0422c4c55b3eaca318e6cac32%7C0%7C0%7C638258174209955308%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=mH7TRJny1YUOsG%2BeFXno4xdvsLAjz%2BRkQgCnLfehXvQ%3D&reserved=0, does it imply that most of the times Tomcat is running behind HTTP proxies and not TCP proxies?Or does it mean that, Tomcat or applications running in Tomcat does notneed the remote client address information? I can't speak for anybody else, but I use Apache httpd as my reverse-proxy and I do terminate TLS. I also use it for load-balancing/fail-over, caching, some authorization, etc. I wouldn't be able to use a TCP load-balancer because I hide multiple servicesbehind my reverse-proxy which run in different places. It's not just s dumb pass-through.Hope that helps, -chris-----Original Message----- From: Christopher Schultz <ch...@christopherschultz.net> Sent: Monday, May 8, 2023 3:40 PM To: users@tomcat.apache.org Subject: [External] Re: Supporting Proxy Protocol in Tomcat Amit, On 5/4/23 16:07, Amit Pande wrote:We have a similar requirement as mentioned in the below enhancementrequest.https://bz/. a%2F&data=05%7C01%7CAmit.Pande%40veritas.com%7C07ebe3c927ed4b787206 08 db519ccce8%7Cfc8e13c0422c4c55b3eaca318e6cac32%7C0%7C0%7C63819350613 56 24269%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiL CJ BTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=3UFyiGJ9ZgtLqUzY9 JM CK2MfwKN3OAOKdr6JmTUGkPw%3D&reserved=0 pache.org%2Fbugzilla%2Fshow_bug.cgi%3Fid%3D57830&data=05%7C01%7CAmit. P ande%40veritas.com%7Cab789327b86845e8ad7208db50046f55%7Cfc8e13c0422 c4 c 55b3eaca318e6cac32%7C0%7C0%7C638191752206669206%7CUnknown%7CTWFpbGZ sb 3 d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3 D% 7 C3000%7C%7C%7C&sdata=6TXyKzlyjY3AIi6zQMFn2j9BhtwYo6Jkrd1V3nOl4mY%3D &r e served=0 Is there any plan to add this support in Tomcat in future releases?Nothing at the moment that I know of. I thought that markt had looked at this a while back and said it didn'tlook too difficult. It does require Tomcat to handle the stream directly and not just rely on Java's SSLServerSocket. I thought that had been done at some point, but it may not have. Handling the stream directly may have some other advantages as well, though it definitely makes the code more complicated.Also, since this was requested long time back and there is no update, are there any other alternatives to pass the client information from load balancer to Tomcat in situations where there is no SSL termination at load balancer?You mean like a network load balancer where the lb is just proxyingbytes and not looking at the data at all? The PROXY protocol really is the best way to do that, honestly.-chris -------------------------------------------------------------------- - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org -------------------------------------------------------------------- - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org--------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org-- Jonathan | exabr...@gmail.comPessimists, see a jar as half empty. Optimists, in contrast, see it as half full. Engineers, of course, understand the glass is twice as big as it needs to be.--------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org--------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org--------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
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