path: root/hurd/translator/pfinet/implementation.mdwn

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The `pfinet` server is a hacked Linux internet implementation with a glue layer
translating between the Hurd [[RPC]]s and the middle layer of the Linux
implementation.


# Bugs

## Those Listed on [[Open_Issues]]

## [[IPv6]]

## IRC, freenode, #hurd, 2013-04-03

    <braunr> youpi: there are indeed historical bugs with small packets and
      tcp_nodelay in linux 2.0/2.2 tcp/ip
    <youpi> oh
    <braunr> http://jl-icase.home.comcast.net/~jl-icase/LinuxTCP2.html

## MAC Addresses

[[!tag open_issue_hurd]]


### IRC, freenode, #hurd, 2013-09-21

    <jproulx> what command will show me the MAC address of an interface?
    <youpi> ah, too bad inetutils-ifconfig doesn't seem to be showing it
    <youpi> I don't think we already have a tool for that
    <youpi> it would be a matter of patching inetutils-ifconfig


## Routing Tables

[[!tag open_issue_hurd]]


### IRC, freenode, #hurd, 2013-09-21

    <jproulx> Hmmm, OK I can work around that, what about routing tables, can I
      see them?  can I add routes besides the pfinet -g default route?
    <youpi> I don't think there is a tool for that yet
    <youpi> it's not plugged inside pfinet anyway


## IRC, freenode, #hurd, 2014-01-15

    <braunr> 2014-01-14 23:06:38 IPv4 socket creation failed: Computer bought
      the farm
    <braunr> :O
    <youpi> hum :)
    <youpi> perhaps related with your change for "lo" performance?
    <braunr> unlikely
    <youpi> I don't see what would have changed in pfinet otherwise
    <braunr> mig generated code if i'm right
    <braunr> lib*fs
    <braunr> libfshelp
    <braunr> looks plenty enough
    <braunr> teythoon's output has been quite high, it's not so suprising to
      spot such integration issues


### IRC, freenode, #hurd, 2014-01-16

    <braunr> teythoon: so, did you see we have bugs on the latest hurd packages
      :)
    <braunr> for some reason, exim4 starts nicely on darnassus, but not on
      another test vm
    <braunr> and there is a "deallocate invalid name" error at boot time
    <braunr> it's also present with your packages
    <teythoon> yes

    <braunr> not being able to start exim4 and other servers on some machines,
      apparently randomly, is a bit frightening to me
    <braunr> as the message says, "most probably a bug"
    <teythoon> yes
    <braunr> so we have to get rid of it as soon as possible so we can get to
      the more interesting stuff
    <teythoon> but there is no way to attribute this message to a process
    <braunr> well, for those at boot time, there is
    <teythoon> ?
    <braunr> if i disable exim, i don't get it :p
    <teythoon> oh ?
    <braunr> but again, it doesn't occur on all machines
    <braunr> and that part is the one i don't like at all
    <teythoon> still, is it in exim, pfinet, pflocal, ... ?
    <teythoon> no way to answer that
    <braunr> ah right sorry
    <braunr> it's probably pfinet, since exim says computer bought the farm on
      a socket
    <braunr> pflocal had its same pid
    <teythoon> ok
    <braunr> and after an upgrade, i don't reproduce that
    <braunr> good, in a way
    <braunr> there still is the one, after auth
    <teythoon> yes
    <teythoon> i'm seeing that too
    <braunr> (as in "exec init proc auth"
    <braunr> shouldn't be too hard to fix
    <braunr> i'll settle on this one after i'm done with libps
    <gnu_srs> (15:21:34) braunr: it's probably pfinet, since exim says computer
      bought the farm on a socket:
    <gnu_srs> remember my having problems with removing a socket file, maybe
      related, probably not pfinet then?
    <braunr> gnu_srs: unlikely
    <braunr> that pfinet bug may have been completely transient
    <braunr> fixed by upgrading packages
    <gnu_srs> braunr: k!

    <braunr> and exim4 keeps crashing on my hurd instance at home
    <braunr> (pfinet actually)
    <braunr> uh, ok, a stupid typo ..
    <braunr> teythoon: --natmask in the /servers/socket/2 node, but correct
      options in the 26 one .... :)


### IRC, freenode, #hurd, 2014-01-17

    <teythoon> braunr: *phew*


# Reimplementation, [[!GNU_Savannah_task 5469]]

## [[community/gsoc/project_ideas/tcp_ip_stack]]

## IRC, freenode, #hurd, 2013-04-03

[[!tag open_issue_hurd]]

    <youpi> I was thinking about just using liblwip this afternoon, btw
    <braunr> what is it ?
    <braunr> hm, why not
    <braunr> i would still prefer using code from netbsd
    <braunr> especially now with the rump kernel project making it even easier

[[open_issues/user-space_device_drivers]], *External Projects*, *The Anykernel
and Rump Kernels*.

    <youpi> well, whatever is easy to maintain up to date actually
    <braunr> netbsd's focus on general portability normally makes it easy to
      maintain
    <braunr> the author of the rump project was able to make netbsd code run in
      browsers :)
    <braunr> and he actually showed clients using the networking stack on
      windows, remotely (not in the same process)
    <braunr> so that's very close to what we want
    <youpi> indeed
    <youpi> though liblwip is exactly the same portability focus :)
    <braunr> apparently, for embedded systems
    <youpi> but bsd's code is probably better
    <youpi> yes
    <braunr> i think so, more general purpose, larger user base
    <youpi> I used it for the stubdomains in Xen
    <youpi> (it = lwip)
    <braunr> ok

Cloudius OSv apparently have isolated/re-used a BSD networking stack,
<http://www.osv.io/>, <https://github.com/cloudius-systems/osv>.


## IRC, freenode, #hurd, 2014-02-06

    <akshay1994> Hello Everyone! Just set up my Hurd system. I need some help
      now, in selecting a project on which i can work, and delving further into
      this. 
    <braunr> akshay1994: what are you interested in ?
    <akshay1994> I was going through the project ideas. Found TCP/IP Stack, and
      CD Audio grabbing interesting.
    <braunr> cd audio grabbing ?
    <braunr> hm why not
    <braunr> akshay1994: you have to understand that, when it come to drivers,
      we prefer reusing existing implementations in contained servers than
      rewriting ourselves
    <braunr> the networking stack project would be very interesting, yes
    <akshay1994> Yes. I was indeed reading about the network stack. 
    <akshay1994> So we need an easily modularise-able userspace stack, which we
      can run as a server for now. 
    <akshay1994> And split into different protocol layers later.
    <braunr> hum no
    <braunr> we probably want to stick to the model we're currently using with
      pfinet
    <braunr> for network drivers, yes
    <braunr> i strongly suspect we want the whole IPv4/IPv6 networking stack in
      a single server
    <braunr> and writing glue code so that it works on the hurd
    <braunr> then, you may want to add hooks for firewall/qos/etc...
    <braunr> (although i think qos should be embedded to)
    <braunr> sjbalaji: i also suggest reusing the netbsd networking stack,
      since netbsd is well known for its clean portable code, and it has a
      rather large user base (compared to us or other less known projects) and
      is well maintained
    <braunr> the rump project might make porting even easier

[[open_issues/user-space_device_drivers]], *External Projects*, *The Anykernel
and Rump Kernels*.

    <akshay1994> okay! I was reading the project idea, where they mention that
      a true hurdish stack will use a set of translator processes , each
      implementing a different protocol layer
    <braunr> a true hurdish stack would
    <braunr> i strongly doubt we'll ever have the man power to write one
    <braunr> i don't really see the point either to be honest :/
    <akshay1994> haha! 
    <braunr> but others have better vision than me for these things so i don't
      know
    <akshay1994> So, what are the problems we are facing with the current
      pfinet implementation?
    <braunr> it's old
    <braunr> meaning it doesn't implement some features that may be important,
      and has a few bugs due to lack of maintenance
    <braunr> maintenance here being updating the code base with a newer
      version, and we don't particularly want to continue grabbing code from
      linux 2.2 :)
    <akshay1994> I see. I was just skimming through google, about userspace
      network stacks, but I think I might need to first understand how the
      current one works and interacts with the system, before proceeding
      further!
    <braunr> yes
    <braunr> the very idea of a userspace stack itself has little implications
    <braunr> it basically means it doesn't run in system mode, and instead of
      directly calling functions, it uses RPCs to communicate with other parts
      of the system

    <akshay1994> braunr: I looked at the netBSD net-stack, and also how hurd
      (and mach) work. I'm starting with the hacking guide. Seems a little
      difficult :p
    <akshay1994> But i feel, I'll get over it. Any tips?
    <braunr> akshay1994: it's not straightforward
    <akshay1994> I know. Browsing through pfinet gave me an idea, how complex a
      thing I'm trying to deal with in first try :p


### IRC, freenode, #hurd, 2014-02-09

    <antrik> braunr: the point of a hurdisch network stack is the same as a
      hurdish block layer, and in fact anything hurdish: you can do things like
      tunelling in a natural manner, rather than needing special loopback code
      and complex control interfaces
    <braunr> antrik: i don't see how something like the current pfinet would
      prevent that


# IRC, freenode, #hurd, 2013-10-31

    <braunr> looks like there is a deadlock in pfinet
    <braunr> maybe triggered or caused by my thread destruction patch

[[open_issues/libpthread/t/fix_have_kernel_resources]].