This is a seriously beefed up chroot kind of thing. The process
is jailed along the same lines as a chroot does it, but with
additional tough restrictions imposed on what the superuser can do.
For all I know, it is safe to hand over the root bit inside a
prison to the customer living in that prison, this is what
it was developed for in fact: "real virtual servers".
Each prison has an ip number associated with it, which all IP
communications will be coerced to use and each prison has its own
hostname.
Needless to say, you need more RAM this way, but the advantage is
that each customer can run their own particular version of apache
and not stomp on the toes of their neighbors.
It generally does what one would expect, but setting up a jail
still takes a little knowledge.
A few notes:
I have no scripts for setting up a jail, don't ask me for them.
The IP number should be an alias on one of the interfaces.
mount a /proc in each jail, it will make ps more useable.
/proc/<pid>/status tells the hostname of the prison for
jailed processes.
Quotas are only sensible if you have a mountpoint per prison.
There are no privisions for stopping resource-hogging.
Some "#ifdef INET" and similar may be missing (send patches!)
If somebody wants to take it from here and develop it into
more of a "virtual machine" they should be most welcome!
Tools, comments, patches & documentation most welcome.
Have fun...
Sponsored by: http://www.rndassociates.com/
Run for almost a year by: http://www.servetheweb.com/
Distribute all but the most fundamental malloc types. This time I also
remembered the trick to making things static: Put "static" in front of
them.
A couple of finer points by: bde
socket addresses in mbufs. (Socket buffers are the one exception.) A number
of kernel APIs needed to get fixed in order to make this happen. Also,
fix three protocol families which kept PCBs in mbufs to not malloc them
instead. Delete some old compatibility cruft while we're at it, and add
some new routines in the in_cksum family.
1/ is compatible with the old route(1) in case needed.
2/ actually fixes the problem while vetting bad user input.
note: I have already fixed route(1) so the problem shouldn't occur.
if it does. use 0.0.0.0/0 instead of the word 'default' :)
We need to accept at least one sockaddr with zero length, in order
to be able to set the default route.
Suggested by: Phone conversation with Julian (sleep well!)
Route(1) has a bug that sends a bad message to the kernel. The kernel
trusts it and crashes. Add some sanity checks so that
we don't trust the user quite as much any more.
(also add a comment in if_ethersubr.c)
This commit includes the following changes:
1) Old-style (pr_usrreq()) protocols are no longer supported, the compatibility
glue for them is deleted, and the kernel will panic on boot if any are compiled
in.
2) Certain protocol entry points are modified to take a process structure,
so they they can easily tell whether or not it is possible to sleep, and
also to access credentials.
3) SS_PRIV is no more, and with it goes the SO_PRIVSTATE setsockopt()
call. Protocols should use the process pointer they are now passed.
4) The PF_LOCAL and PF_ROUTE families have been updated to use the new
style, as has the `raw' skeleton family.
5) PF_LOCAL sockets now obey the process's umask when creating a socket
in the filesystem.
As a result, LINT is now broken. I'm hoping that some enterprising hacker
with a bit more time will either make the broken bits work (should be
easy for netipx) or dike them out.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
previous hackery involving struct in_ifaddr and arpcom. Get rid of the
abominable multi_kludge. Update all network interfaces to use the
new machanism. Distressingly few Ethernet drivers program the multicast
filter properly (assuming the hardware has one, which it usually does).
to TAILQs. Fix places which referenced these for no good reason
that I can see (the references remain, but were fixed to compile
again; they are still questionable).
purpose, other than to get in the way of the ARP table and cause
"can't allocate llinfo" errors.
This change may cause gated or routed to start complaining when adding
such routes. If so, these programs will need to be fixed to not try
to add these routes.
Reviewed by: wollman
Submitted by: Mike Mitchell, supervisor@alb.asctmd.com
This is a bulk mport of Mike's IPX/SPX protocol stacks and all the
related gunf that goes with it..
it is not guaranteed to work 100% correctly at this time
but as we had several people trying to work on it
I figured it would be better to get it checked in so
they could all get teh same thing to work on..
Mikes been using it for a year or so
but on 2.0
more changes and stuff will be merged in from other developers now that this is in.
Mike Mitchell, Network Engineer
AMTECH Systems Corporation, Technology and Manufacturing
8600 Jefferson Street, Albuquerque, New Mexico 87113 (505) 856-8000
supervisor@alb.asctmd.com
there may even be LKMs.) Also, change the internal name of `unixdomain'
to `localdomain' since AF_LOCAL is now the preferred name of this family.
Declare netisr correctly and in the right place.
and one set by the protocol family. Also add another parameter to
rtalloc1() to allow for any interface flags to be ignored; currently
this is only useful for RTF_PRCLONING. Get rid of rt_prflags and re-unite
with rt_flags. Add T/TCP ``route metrics''.
NB: YOU MUST RECOMPILE `route' AND OTHER RELATED PROGRAMS AS A RESULT OF
THIS CHANGE.
This also adds a new interface parameter, `ifi_physical', which will
eventually replace IFF_ALTPHYS as the mechanism for specifying the
particular physical connection desired on a multiple-connection card.
NB: YOU MUST RECOMPILE `ifconfig' AND OTHER RELATED PROGRAMS AS A RESULT OF
THIS CHANGE.
a route. (This still doesn't work, but it doesn't panic now.) It looks
like there may be a number of incipient bugs in this code.
Also, get ready for the time when all IP gateway routes are cloning, which
is necessary to keep proper TCP statistics.
- Allow PPP to run multicasts natively.
- Deal properly with lots of similarly-named interfaces.
- Don't sign-extend if_flags.
NB: the last fix (to rtsock.c) must be reversed when we expand if_flags to a
reasonable size.
Submitted by: Mark Treacy
