Capabilities to provide UDP services with Apache

[Matthew Gress <za...@visi.com>]

I have already posted to the users list and was referred here.

Apache can communicate with several TCP protocols but I have a module
project which needs UDP communications as well.  I have searched the
documentation, archives, and 2.0.48 HTTPD server source for this and all
I find are references for beos, testcockets, LDAP,  DNS lookups and some
OS-related stuff regarding NIS.  Oh yeah, and an old SSL exploit
apparently made HTTPD open a UDP listener too...

In any case, I have not found a reference to how to configure apache to
do this and need to know where I should start to create or adapt for 
this functionality.
We realized that we might have to code this personally to make this
work, but would rather not if it is already in existence.

Another question I have is, can we create a module that services UDP 
"connections" without
hitting the cental apache server code.

Thanks!
Matthew Gress

Re: Capabilities to provide UDP services with Apache

[Jeff Trawick <tr...@attglobal.net>]

Matthew Gress wrote:

> Another question I have is, can we create a module that services UDP 
> "connections" without
> hitting the cental apache server code.

what has to happen when a datagram is received?  something totally in the scope 
of the module, or should Apache's HTTP processing be performed on a request 
extracted from the datagram?

Re: Capabilities to provide UDP (not TCP) services with Apache

[za...@visi.com]

Yeah, it is a little weird, but not HTTP, another protocol on top of UDP
specific to our application.  

MPM, so that section is the jumping-off point for considering UDP instead of
TCP, and the mod_echo for refernce to another protocol (though TCP) being
implemented in a module.  

In fact, the worker thread model was in my follow-up question, since we would
want to make sure that our module (if we can write one that does what we want
without hitting the "central" code) would still be able to take advantage of
those worker-model schemes.

As you can tell I am not as familiar with the deep architecture, just starting
the investigation and looking for pointers.

Thanks for your response!
Matthew

Quoting "William A. Rowe, Jr." <wr...@rowe-clan.net>:

> I'm totally confused now :)  Do you want Apache to handle the UDP request
> as an HTTP request?  Or do you want a UDP port that does something else?
> 
> First if you want a pool of UDP listeners, explore the MPM - it's the MPM's
> job to dispatch requests from TCP, so it would make sense to build upon
> another MPM to handle the connections.
> 
> Second if you want to handle a protocol other than HTTP, see mod_echo
> as an example (trivial of course, just as the echo protocol is trivial.)
> 
> Bill
> 
> At 06:22 PM 2/4/2004, Matthew Gress wrote:
> >I am curious about what it would take to use an alternate protocol at layer
> 4 with apache.
> >
> >>I have already posted to the users list and was referred here.
> >>
> >>Apache can communicate with several TCP protocols but I have a module
> >>project which needs UDP communications as well.  I have searched the
> >>documentation, archives, and 2.0.48 HTTPD server source for this and all
> >>I find are references for beos, testcockets, LDAP,  DNS lookups and some
> >>OS-related stuff regarding NIS.  Oh yeah, and an old SSL exploit
> >>apparently made HTTPD open a UDP listener too...
> >>
> >>In any case, I have not found a reference to how to configure apache to
> >>do this and need to know where I should start to create or adapt for this
> functionality.
> >>We realized that we might have to code this personally to make this
> >>work, but would rather not if it is already in existence.
> >>
> >>Another question I have is, can we create a module that services UDP
> "connections" without
> >>hitting the cental apache server code.
> >>
> >>Thanks!
> >>Matthew Gress

Re: Capabilities to provide UDP (not TCP) services with Apache

["William A. Rowe, Jr." <wr...@rowe-clan.net>]

I'm totally confused now :)  Do you want Apache to handle the UDP request
as an HTTP request?  Or do you want a UDP port that does something else?

First if you want a pool of UDP listeners, explore the MPM - it's the MPM's
job to dispatch requests from TCP, so it would make sense to build upon
another MPM to handle the connections.

Second if you want to handle a protocol other than HTTP, see mod_echo
as an example (trivial of course, just as the echo protocol is trivial.)

Bill

At 06:22 PM 2/4/2004, Matthew Gress wrote:
>I am curious about what it would take to use an alternate protocol at layer 4 with apache.
>
>>I have already posted to the users list and was referred here.
>>
>>Apache can communicate with several TCP protocols but I have a module
>>project which needs UDP communications as well.  I have searched the
>>documentation, archives, and 2.0.48 HTTPD server source for this and all
>>I find are references for beos, testcockets, LDAP,  DNS lookups and some
>>OS-related stuff regarding NIS.  Oh yeah, and an old SSL exploit
>>apparently made HTTPD open a UDP listener too...
>>
>>In any case, I have not found a reference to how to configure apache to
>>do this and need to know where I should start to create or adapt for this functionality.
>>We realized that we might have to code this personally to make this
>>work, but would rather not if it is already in existence.
>>
>>Another question I have is, can we create a module that services UDP "connections" without
>>hitting the cental apache server code.
>>
>>Thanks!
>>Matthew Gress

Capabilities to provide UDP (not TCP) services with Apache

[Matthew Gress <za...@visi.com>]

I am curious about what it would take to use an alternate protocol at 
layer 4 with apache.

> I have already posted to the users list and was referred here.
>
> Apache can communicate with several TCP protocols but I have a module
> project which needs UDP communications as well.  I have searched the
> documentation, archives, and 2.0.48 HTTPD server source for this and all
> I find are references for beos, testcockets, LDAP,  DNS lookups and some
> OS-related stuff regarding NIS.  Oh yeah, and an old SSL exploit
> apparently made HTTPD open a UDP listener too...
>
> In any case, I have not found a reference to how to configure apache to
> do this and need to know where I should start to create or adapt for 
> this functionality.
> We realized that we might have to code this personally to make this
> work, but would rather not if it is already in existence.
>
> Another question I have is, can we create a module that services UDP 
> "connections" without
> hitting the cental apache server code.
>
> Thanks!
> Matthew Gress
>
>

Re: Capabilities to provide UDP services with Apache

[Nick Kew <ni...@webthing.com>]

On Wed, 28 Jan 2004, Matthew Gress wrote:

> In any case, I have not found a reference to how to configure apache to
> do this and need to know where I should start to create or adapt for
> this functionality.

I think you just have to write it.  The nearest thing Apache has to
a utility library is the APR.

> Another question I have is, can we create a module that services UDP
> "connections" without
> hitting the cental apache server code.

Are you sure this prospective module wants to live within Apache?
What are you expecting this to gain for you over (say) an RPC-based
daemon sitting alongside Apache?

-- 
Nick Kew