mutable contents of struct prison (hostname, securelevel, refcount,
pr_linux, ...)
o Generally introduce mtx_lock()/mtx_unlock() calls throughout kern/
so as to enforce these protections, in particular, in kern_mib.c
protection sysctl access to the hostname and securelevel, as well as
kern_prot.c access to the securelevel for access control purposes.
o Rewrite linux emulator abstractions for accessing per-jail linux
mib entries (osname, osrelease, osversion) so that they don't return
a pointer to the text in the struct linux_prison, rather, a copy
to an array passed into the calls. Likewise, update linprocfs to
use these primitives.
o Update in_pcb.c to always use prison_getip() rather than directly
accessing struct prison.
Reviewed by: jhb
readability.
o Conditionalize only the SYSCTL definitions for the regression
tree, not the variables itself, decreasing the number of #ifdef
REGRESSIONs scattered in kern_mib.c, and making the code more
readable.
Sponsored by: DARPA, NAI Labs
sysctl_req', which describes in-progress sysctl requests. This permits
sysctl handlers to have access to the current thread, permitting work
on implementing td->td_ucred, migration of suser() to using struct
thread to derive the appropriate ucred, and allowing struct thread to be
passed down to other code, such as network code where td is not currently
available (and curproc is used).
o Note: netncp and netsmb are not updated to reflect this change, as they
are not currently KSE-adapted.
Reviewed by: julian
Obtained from: TrustedBSD Project
consistent with the one other function in the file, and prevents long
lines in up-coming changes. This nominally pulls kern_mib.c a little
further down the long path to style(9) compliance.
'regression.*'.
o Add 'regression.securelevel_nonmonotonic', conditional on 'options
REGRESSION', which allows the securelevel to be lowered for the purposes
of efficient regression testing of securelevel policy decisions.
Regression tests for securelevels will be committed shortly.
NOTE: 'options REGRESSION' should never be used on production machines, as
it permits violation of system invariants so as to improve the ability to
effectively test edge cases, and improve testing efficiency.
one is present in the current jail, otherwise, to return the global
securelevel.
o If the securelevel is being updated, require that it be greater than
the maximum of local and global, if a local securelevel exists,
otherwise, just maximum of the global. If there is a local
securelevel, update the local one instead of the global one.
o Note: this does allow local securelevels to lag behind the global one
as long as the local one is not updated following a global increase.
Obtained from: TrustedBSD Project
Tunables are now derived at boot time from maxusers. ie: change maxusers
via a tunable and all the derivative settings change. You can change
the other tunables individually as well. Even hz etc is tunable.
been made machine independent and various other adjustments have been made
to support Alpha SMP.
- It splits the per-process portions of hardclock() and statclock() off
into hardclock_process() and statclock_process() respectively. hardclock()
and statclock() call the *_process() functions for the current process so
that UP systems will run as before. For SMP systems, it is simply necessary
to ensure that all other processors execute the *_process() functions when the
main clock functions are triggered on one CPU by an interrupt. For the alpha
4100, clock interrupts are delievered in a staggered broadcast fashion, so
we simply call hardclock/statclock on the boot CPU and call the *_process()
functions on the secondaries. For x86, we call statclock and hardclock as
usual and then call forward_hardclock/statclock in the MD code to send an IPI
to cause the AP's to execute forwared_hardclock/statclock which then call the
*_process() functions.
- forward_signal() and forward_roundrobin() have been reworked to be MI and to
involve less hackery. Now the cpu doing the forward sets any flags, etc. and
sends a very simple IPI_AST to the other cpu(s). AST IPIs now just basically
return so that they can execute ast() and don't bother with setting the
astpending or needresched flags themselves. This also removes the loop in
forward_signal() as sched_lock closes the race condition that the loop worked
around.
- need_resched(), resched_wanted() and clear_resched() have been changed to take
a process to act on rather than assuming curproc so that they can be used to
implement forward_roundrobin() as described above.
- Various other SMP variables have been moved to a MI subr_smp.c and a new
header sys/smp.h declares MI SMP variables and API's. The IPI API's from
machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h.
- The globaldata_register() and globaldata_find() functions as well as the
SLIST of globaldata structures has become MI and moved into subr_smp.c.
Also, the globaldata list is only available if SMP support is compiled in.
Reviewed by: jake, peter
Looked over by: eivind
credential structure, ucred (cr->cr_prison).
o Allow jail inheritence to be a function of credential inheritence.
o Abstract prison structure reference counting behind pr_hold() and
pr_free(), invoked by the similarly named credential reference
management functions, removing this code from per-ABI fork/exit code.
o Modify various jail() functions to use struct ucred arguments instead
of struct proc arguments.
o Introduce jailed() function to determine if a credential is jailed,
rather than directly checking pointers all over the place.
o Convert PRISON_CHECK() macro to prison_check() function.
o Move jail() function prototypes to jail.h.
o Emulate the P_JAILED flag in fill_kinfo_proc() and no longer set the
flag in the process flags field itself.
o Eliminate that "const" qualifier from suser/p_can/etc to reflect
mutex use.
Notes:
o Some further cleanup of the linux/jail code is still required.
o It's now possible to consider resolving some of the process vs
credential based permission checking confusion in the socket code.
o Mutex protection of struct prison is still not present, and is
required to protect the reference count plus some fields in the
structure.
Reviewed by: freebsd-arch
Obtained from: TrustedBSD Project
- All processes go into the same array of queues, with different
scheduling classes using different portions of the array. This
allows user processes to have their priorities propogated up into
interrupt thread range if need be.
- I chose 64 run queues as an arbitrary number that is greater than
32. We used to have 4 separate arrays of 32 queues each, so this
may not be optimal. The new run queue code was written with this
in mind; changing the number of run queues only requires changing
constants in runq.h and adjusting the priority levels.
- The new run queue code takes the run queue as a parameter. This
is intended to be used to create per-cpu run queues. Implement
wrappers for compatibility with the old interface which pass in
the global run queue structure.
- Group the priority level, user priority, native priority (before
propogation) and the scheduling class into a struct priority.
- Change any hard coded priority levels that I found to use
symbolic constants (TTIPRI and TTOPRI).
- Remove the curpriority global variable and use that of curproc.
This was used to detect when a process' priority had lowered and
it should yield. We now effectively yield on every interrupt.
- Activate propogate_priority(). It should now have the desired
effect without needing to also propogate the scheduling class.
- Temporarily comment out the call to vm_page_zero_idle() in the
idle loop. It interfered with propogate_priority() because
the idle process needed to do a non-blocking acquire of Giant
and then other processes would try to propogate their priority
onto it. The idle process should not do anything except idle.
vm_page_zero_idle() will return in the form of an idle priority
kernel thread which is woken up at apprioriate times by the vm
system.
- Update struct kinfo_proc to the new priority interface. Deliberately
change its size by adjusting the spare fields. It remained the same
size, but the layout has changed, so userland processes that use it
would parse the data incorrectly. The size constraint should really
be changed to an arbitrary version number. Also add a debug.sizeof
sysctl node for struct kinfo_proc.
Trimmed an extra sysctl when I moved kern.suser_permitted from kern_mib.c
to kern_prot.c. This commit should restore it, as well as fix the
resulting build problems.
Submitted by: asmodai
kern_prot, which cleans up some namespace issues
o Don't need a special handler to limit un-setting, as suser is used to
protect suser_permitted, making it one-way by definition.
Suggested by: bde
returning anything but EPERM.
o suser is enabled by default; once disabled, cannot be reenabled
o To be used in alternative security models where uid0 does not connote
additional privileges
o Should be noted that uid0 still has some additional powers as it
owns many important files and executables, so suffers from the same
fundamental security flaws as securelevels. This is fixed with
MAC integrity protection code (in progress)
o Not safe for consumption unless you are *really* sure you don't want
things like shutdown to work, et al :-)
Obtained from: TrustedBSD Project
<sys/bio.h>.
<sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall
not be made a nested include according to bdes teachings on the
subject of nested includes.
Diskdrivers and similar stuff below specfs::strategy() should no
longer need to include <sys/buf.> unless they need caching of data.
Still a few bogus uses of struct buf to track down.
Repocopy by: peter
``jail'', and move the set_hostname_allowed sysctl there, as well as
fixing a bug in the sysctl that resulted in jails being over-limited
(preventing them from reading as well as writing the hostname). Also,
correct some formatting issues, courtesy bde :-).
Reviewed by: phk
Approved by: jkh
or not a process in a jail, with privilege, may set the jail's hostname.
Defaults to 1, which permits this. May be set to 0 by a process with
appropriate privilege outside of jail. Preventing hostname renaming
from within a jail is currently required to make jails manageable, as they
a currently identifiable only by hostname using /proc, which may be
modified without this sysctl being set to 0. This will be documented
in upcoming man commits.
Authorized by: jkh, the ever-patient
discussed on current.
The following variables are defined (for now):
osname (defaults to "Linux")
Allow users to change the name of the OS as returned by uname(2),
specially added for all those Linux Netscape users and statistics
maniacs :-) We now have what we all wanted!
osrelease (defaults to "2.2.5")
Allow users to change the version of the OS as returned by uname(2).
Since -current supports glibc2.1 now, change the default to 2.2.5
(was 2.0.36).
oss_version (defaults to 198144 [0x030600])
This one will be used by the OSS_GETVERSION ioctl (PR 12917) which I
can commit now that we have the MIB. The default version number is the
lowest version possible with the current 'encoding'.
A note about imprisoned processes (see jail(2)):
These variables are copy-on-write (as suggested by phk). This means that
imprisoned processes will use the system wide value unless it is written/set
by the process. From that moment on, a copy local to the prison will be
used.
A note about the implementation:
I choose to add a single pointer to struct prison, because I didn't like the
idea of changing struct prison every time I come up with a new variable. As
a side effect, the extra storage is only needed when a variable is set from
within the prison. This also minimizes kernel bloat when the Linuxulator is
not used; both compiled in or as a module.
Reviewed by: bde (first version only) and phk
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/
directory containing rc.conf.local and rc.local, and possibly other
things in the future.
This sysctl is used by the diskless startup code and new rc.conf. If
it cannot be found or is empty, the system should revert to using /etc.
- moved definition of MACHINE_ARCH from cpu.h to parm.h as alpha.
- Added definitions of _MACHINE and _MACHINE_ARCH.
- Added hw.ispc98. The hw.ispc98 is 1 in PC98 kernel and is 0 in
IBM-PC kernel.
Discussed with: John Birrell <jb@FreeBSD.ORG>
_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.
Fix for RTPRIO scheduler to eliminate invalid context switches.
POSIX.4 headers and sysctl variables. Nothing should change
unless POSIX4 is defined or _POSIX_VERSION is set to 199309.
nothing good except of opening a can of (potential or real) security
holes. People maintaining a machine with higher security requirements
need to be on the console anyway, so there's no point in not forcing
them to reboot before starting maintenance.
Agreed by: hackers, guido
(phk's) sysctl framework, and I needed special code to disambiguate
the VFS_GENERIC node from the VFS_VFSCONF leaf, so I only converted
the leaves to the FreeBSD framework. The error handling isn't quite
right. CSRGS's sysctls seem to return ENOTDIR too much and FreeBSD's
sysctls don't agree with the man page.
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.
