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/
file works with libpthread, but when built into libc_r which has a non-weak
symbol of the same name, the linker behaves unpredicatably and sometimes
links the wrong symbol. The linker behaviour is a byproduct of what
the program calls from object to object so it is like winning a lottery
if the program actually works. The odds are quite good - 95:1, I think.
We need a sure thing, though, so weak symbols can't be used instead
of renaming things.
_KPOSIX_PRIORITY_SCHEDULING options to work. Changes:
Change all "posix4" to "p1003_1b". Misnamed files are left
as "posix4" until I'm told if I can simply delete them and add
new ones;
Add _POSIX_PRIORITY_SCHEDULING system calls for FreeBSD and Linux;
Add man pages for _POSIX_PRIORITY_SCHEDULING system calls;
Add options to LINT;
Minor fixes to P1003_1B code during testing.
__msync13. The old one got moved to compat_12. Wrap __msync13 up
to look like FreeBSD's msync and be careful to respect the fact that
MS_SYNC is 0x0000 on FreeBSD, but 0x0004 on NetBSD.
Include the architecture specific sys makefile like previously, but
what this contains differs. It defines MDASM which list architecture
specific asm code that *replaces* syscalls of the same name defined
in MIASM (which gets defined by the syscall.mk or netbsd_syscall.mk
dependent of NETBSD_SYSCALLS being defined). If a syscall has a
C source implementation or something funny done to it, or just doesn't
need default asm source generated for it, then it is listed in NOASM.
syscall.mk is generated by makesyscalls.sh with other syscall files.
netbsd_syscall.mk is a hand-generated equivalent. So if a new syscall
is added and no other makefiles are edited, it will automatically have
the default asm source generated for it (whether you want it or not).
Anything listed in MDASM gets added to SRCS and gets built. For
each syscall name in MIASM, if it doesn't exist in MDASM or NOASM,
it gets added to the ASM or ASMR lists to have code generated for it.
If the syscall name was listed in HIDDEN_SYSCALLS (intended for use
by libc_r, not libc which has it defined, but empty), then the name
is added to the ASMR list and gets renamed before being built;
otherwise it is added to the ASM list and gets built with the same
name.
I wonder if this is too complicated. But it works on both i386 and alpha.
so that all these makefiles can be used to build libc_r too.
Added .if ${LIB} == "c" tests to restrict man page builds to libc
to avoid needlessly building them with libc_r too.
Split libc Makefile into Makefile and Makefile.inc to allow the
libc_r Makefile to include Makefile.inc too.
- dependencies actually work (I need this to propagate some fixes
in <machine/asm.h>)
- the cpp pipeline goes away, so errors can't leak out of it and
an ANSI cpp is automatically used.
- it's simpler - standard rules get used instead of repetitive
special rules. (This showed bugs in the strip steps in the
standard rules. The wrong strip flag was also used for *.po
here.)
Removed some ${ECHO}s and `@'s. Normal make echoing of what is
being done is now not much more verbose than the echo messages
were, and is more useful.
