History log of /freebsd-10.1-release/sys/i386/ibcs2/ibcs2_fcntl.c
Revision Date Author Comments
(<<< Hide modified files)
(Show modified files >>>)
# 272461 02-Oct-2014 gjb

Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

# 256281 10-Oct-2013 gjb

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation


# 255219 04-Sep-2013 pjd

Change the cap_rights_t type from uint64_t to a structure that we can extend
in the future in a backward compatible (API and ABI) way.

The cap_rights_t represents capability rights. We used to use one bit to
represent one right, but we are running out of spare bits. Currently the new
structure provides place for 114 rights (so 50 more than the previous
cap_rights_t), but it is possible to grow the structure to hold at least 285
rights, although we can make it even larger if 285 rights won't be enough.

The structure definition looks like this:

struct cap_rights {
uint64_t cr_rights[CAP_RIGHTS_VERSION + 2];
};

The initial CAP_RIGHTS_VERSION is 0.

The top two bits in the first element of the cr_rights[] array contain total
number of elements in the array - 2. This means if those two bits are equal to
0, we have 2 array elements.

The top two bits in all remaining array elements should be 0.
The next five bits in all array elements contain array index. Only one bit is
used and bit position in this five-bits range defines array index. This means
there can be at most five array elements in the future.

To define new right the CAPRIGHT() macro must be used. The macro takes two
arguments - an array index and a bit to set, eg.

#define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL)

We still support aliases that combine few rights, but the rights have to belong
to the same array element, eg:

#define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL)
#define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL)

#define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP)

There is new API to manage the new cap_rights_t structure:

cap_rights_t *cap_rights_init(cap_rights_t *rights, ...);
void cap_rights_set(cap_rights_t *rights, ...);
void cap_rights_clear(cap_rights_t *rights, ...);
bool cap_rights_is_set(const cap_rights_t *rights, ...);

bool cap_rights_is_valid(const cap_rights_t *rights);
void cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src);
void cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src);
bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little);

Capability rights to the cap_rights_init(), cap_rights_set(),
cap_rights_clear() and cap_rights_is_set() functions are provided by
separating them with commas, eg:

cap_rights_t rights;

cap_rights_init(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT);

There is no need to terminate the list of rights, as those functions are
actually macros that take care of the termination, eg:

#define cap_rights_set(rights, ...) \
__cap_rights_set((rights), __VA_ARGS__, 0ULL)
void __cap_rights_set(cap_rights_t *rights, ...);

Thanks to using one bit as an array index we can assert in those functions that
there are no two rights belonging to different array elements provided
together. For example this is illegal and will be detected, because CAP_LOOKUP
belongs to element 0 and CAP_PDKILL to element 1:

cap_rights_init(&rights, CAP_LOOKUP | CAP_PDKILL);

Providing several rights that belongs to the same array's element this way is
correct, but is not advised. It should only be used for aliases definition.

This commit also breaks compatibility with some existing Capsicum system calls,
but I see no other way to do that. This should be fine as Capsicum is still
experimental and this change is not going to 9.x.

Sponsored by: The FreeBSD Foundation


# 227691 19-Nov-2011 ed

Improve *access*() parameter name consistency.

The current code mixes the use of `flags' and `mode'. This is a bit
confusing, since the faccessat() function as a `flag' parameter to store
the AT_ flag.

Make this less confusing by using the same name as used in the POSIX
specification -- `amode'.


# 224778 11-Aug-2011 rwatson

Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *. With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by: re (bz)
Submitted by: jonathan
Sponsored by: Google Inc


# 177633 26-Mar-2008 dfr

Add the new kernel-mode NFS Lock Manager. To use it instead of the
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.

Highlights include:

* Thread-safe kernel RPC client - many threads can use the same RPC
client handle safely with replies being de-multiplexed at the socket
upcall (typically driven directly by the NIC interrupt) and handed
off to whichever thread matches the reply. For UDP sockets, many RPC
clients can share the same socket. This allows the use of a single
privileged UDP port number to talk to an arbitrary number of remote
hosts.

* Single-threaded kernel RPC server. Adding support for multi-threaded
server would be relatively straightforward and would follow
approximately the Solaris KPI. A single thread should be sufficient
for the NLM since it should rarely block in normal operation.

* Kernel mode NLM server supporting cancel requests and granted
callbacks. I've tested the NLM server reasonably extensively - it
passes both my own tests and the NFS Connectathon locking tests
running on Solaris, Mac OS X and Ubuntu Linux.

* Userland NLM client supported. While the NLM server doesn't have
support for the local NFS client's locking needs, it does have to
field async replies and granted callbacks from remote NLMs that the
local client has contacted. We relay these replies to the userland
rpc.lockd over a local domain RPC socket.

* Robust deadlock detection for the local lock manager. In particular
it will detect deadlocks caused by a lock request that covers more
than one blocking request. As required by the NLM protocol, all
deadlock detection happens synchronously - a user is guaranteed that
if a lock request isn't rejected immediately, the lock will
eventually be granted. The old system allowed for a 'deferred
deadlock' condition where a blocked lock request could wake up and
find that some other deadlock-causing lock owner had beaten them to
the lock.

* Since both local and remote locks are managed by the same kernel
locking code, local and remote processes can safely use file locks
for mutual exclusion. Local processes have no fairness advantage
compared to remote processes when contending to lock a region that
has just been unlocked - the local lock manager enforces a strict
first-come first-served model for both local and remote lockers.

Sponsored by: Isilon Systems
PR: 95247 107555 115524 116679
MFC after: 2 weeks


# 141488 07-Feb-2005 jhb

- Implement ibcs2_emul_find() using kern_alternate_path(). This changes
the semantics in that the returned filename to use is now a kernel
pointer rather than a user space pointer. This required changing the
arguments to the CHECKALT*() macros some and changing the various system
calls that used pathnames to use the kern_foo() functions that can accept
kernel space filename pointers instead of calling the system call
directly.
- Use kern_open(), kern_access(), kern_execve(), kern_mkfifo(), kern_mknod(),
kern_setitimer(), kern_getrusage(), kern_utimes(), kern_unlink(),
kern_chdir(), kern_chmod(), kern_chown(), kern_symlink(), kern_readlink(),
kern_select(), kern_statfs(), kern_fstatfs(), kern_stat(), kern_lstat(),
kern_fstat().
- Drop the unused 'uap' argument from spx_open().
- Replace a stale duplication of vn_access() in xenix_access() lacking
recent additions such as MAC checks, etc. with a call to kern_access().


# 139799 06-Jan-2005 imp

/* -> /*- for license, add FreeBSD tag


# 134266 24-Aug-2004 jhb

Fix the ABI wrappers to use kern_fcntl() rather than calling fcntl()
directly. This removes a few more users of the stackgap and also marks
the syscalls using these wrappers MP safe where appropriate.

Tested on: i386 with linux acroread5
Compiled on: i386, alpha LINT


# 115684 02-Jun-2003 obrien

Use __FBSDID().


# 107849 13-Dec-2002 alfred

SCARGS removal take II.


# 107839 13-Dec-2002 alfred

Backout removal SCARGS, the code freeze is only "selectively" over.


# 107838 13-Dec-2002 alfred

Remove SCARGS.

Reviewed by: md5


# 102003 17-Aug-2002 rwatson

In continuation of early fileop credential changes, modify fo_ioctl() to
accept an 'active_cred' argument reflecting the credential of the thread
initiating the ioctl operation.

- Change fo_ioctl() to accept active_cred; change consumers of the
fo_ioctl() interface to generally pass active_cred from td->td_ucred.
- In fifofs, initialize filetmp.f_cred to ap->a_cred so that the
invocations of soo_ioctl() are provided access to the calling f_cred.
Pass ap->a_td->td_ucred as the active_cred, but note that this is
required because we don't yet distinguish file_cred and active_cred
in invoking VOP's.
- Update kqueue_ioctl() for its new argument.
- Update pipe_ioctl() for its new argument, pass active_cred rather
than td_ucred to MAC for authorization.
- Update soo_ioctl() for its new argument.
- Update vn_ioctl() for its new argument, use active_cred rather than
td->td_ucred to authorize VOP_IOCTL() and the associated VOP_GETATTR().

Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs


# 92761 20-Mar-2002 alfred

Remove __P.


# 89319 13-Jan-2002 alfred

Replace ffind_* with fget calls.

Make fget MPsafe.

Make fgetvp and fgetsock use the fget subsystem to reduce code bloat.

Push giant down in fpathconf().


# 89306 13-Jan-2002 alfred

SMP Lock struct file, filedesc and the global file list.

Seigo Tanimura (tanimura) posted the initial delta.

I've polished it quite a bit reducing the need for locking and
adapting it for KSE.

Locks:

1 mutex in each filedesc
protects all the fields.
protects "struct file" initialization, while a struct file
is being changed from &badfileops -> &pipeops or something
the filedesc should be locked.

1 mutex in each struct file
protects the refcount fields.
doesn't protect anything else.
the flags used for garbage collection have been moved to
f_gcflag which was the FILLER short, this doesn't need
locking because the garbage collection is a single threaded
container.
could likely be made to use a pool mutex.

1 sx lock for the global filelist.

struct file * fhold(struct file *fp);
/* increments reference count on a file */

struct file * fhold_locked(struct file *fp);
/* like fhold but expects file to locked */

struct file * ffind_hold(struct thread *, int fd);
/* finds the struct file in thread, adds one reference and
returns it unlocked */

struct file * ffind_lock(struct thread *, int fd);
/* ffind_hold, but returns file locked */

I still have to smp-safe the fget cruft, I'll get to that asap.


# 83366 12-Sep-2001 julian

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha


# 76166 01-May-2001 markm

Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
other "system" header files.

Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.

Sort sys/*.h includes where possible in affected files.

OK'ed by: bde (with reservations)


# 71489 23-Jan-2001 jhb

Proc locking.


# 51418 19-Sep-1999 green

This is what was "fdfix2.patch," a fix for fd sharing. It's pretty
far-reaching in fd-land, so you'll want to consult the code for
changes. The biggest change is that now, you don't use
fp->f_ops->fo_foo(fp, bar)
but instead
fo_foo(fp, bar),
which increments and decrements the fp refcount upon entry and exit.
Two new calls, fhold() and fdrop(), are provided. Each does what it
seems like it should, and if fdrop() brings the refcount to zero, the
fd is freed as well.

Thanks to peter ("to hell with it, it looks ok to me.") for his review.
Thanks to msmith for keeping me from putting locks everywhere :)

Reviewed by: peter


# 50477 27-Aug-1999 peter

$Id$ -> $FreeBSD$


# 46568 06-May-1999 peter

Add sufficient braces to keep egcs happy about potentially ambiguous
if/else nesting.


# 33071 04-Feb-1998 eivind

Make SPX_HACK a new-style option.


# 30994 06-Nov-1997 phk

Move the "retval" (3rd) parameter from all syscall functions and put
it in struct proc instead.

This fixes a boatload of compiler warning, and removes a lot of cruft
from the sources.

I have not removed the /*ARGSUSED*/, they will require some looking at.

libkvm, ps and other userland struct proc frobbing programs will need
recompiled.


# 27537 20-Jul-1997 bde

Removed unused #includes.


# 24206 24-Mar-1997 bde

Don't include <sys/ioctl.h> in the kernel. Stage 4: include
<sys/ttycom.h> and sometimes <sys/filio.h> instead of <sys/ioctl.h>
in miscellaneous files. Most of these files have nothing to do
with ttys but need to include <sys/ttycom.h> to get the definitions
of TIOC[SG]PGRP which are (ab)used to convert F[SG]ETOWN fcntls into
ioctls.


# 24131 23-Mar-1997 bde

Don't #include <sys/fcntl.h> in <sys/file.h> if KERNEL is defined.
Fixed everything that depended on getting fcntl.h stuff from the wrong
place. Most things don't depend on file.h stuff at all.


# 22975 22-Feb-1997 peter

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.


# 21673 14-Jan-1997 jkh

Make the long-awaited change from $Id$ to $FreeBSD$

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.


# 12218 12-Nov-1995 bde

Added (null for the i386) conversions from ibcs2's bogus fcntl args
struct to the standard bogus fcntl args struct.


# 11527 16-Oct-1995 swallace

Add a hack to emulator to emulat spx device for local X connections.
This is truly a hack. The idea is taken from the Linux ibcs2 emulator.

To use this feature, you must use the option,
options SPX_HACK
in your config.

Also, in /compat/ibcs2/dev, you must do:

lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 X0R@ -> /dev/null
lrwxr-xr-x 1 root wheel 7 Oct 15 22:20 nfsd@ -> socksys
lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 socksys@ -> /dev/null
crw-rw-rw- 1 root wheel 41, 1 Oct 15 22:14 spx

Do NOT use old socksys driver as that has been removed.
This hack needs /compat/ibcs2/dev/spx to be any device that does NOT
exist/configured (so the now non-existant spx major/minor works fine).
When an open() is called, the error ENXIO is checked and then the
path is checked. If spx open detected, then a unix socket is opened
to the hardcoded path "/tmp/.X11-unix/X0".

As the Linux hacker author mentioned, the real way would be to detect
the getmsg/putmsg through /dev/X0R and /dev/spx. Until this true
solution is implemented (if ever), I think this hack is important
enough to be put into the tree, even though I don't like it dirtying
up my clean code (which is what #ifdef SPX_HACK is for).


# 11397 10-Oct-1995 swallace

Remove old files no longer needed.
Add new files created for emulator.
Modify NetBSD import to work with FreeBSD and add new features and
code. The complete emulator is essentially a combination of work/code
implemented by Sean Eric Fagan, Soren Schmidt, Scott Bartram, and myself,
Steven Wallace.

Features of this new emulator system include:

o "clean" code, including strict prototyping.
o Auto-generation of ibcs2 system calls, xenix system calls, isc system
calls. Generation includes system tables, structure definitions,
and prototyping of function calls.
o ibcs2 emulator does not rely on any COMPAT_43 system calls.
o embedded socksys support
o ibcs2 msgsys, semsys, shmsys calls supported if supported in kernel
o alternate /emul/ibcs2 namespace searched first for files in ibcs2
system. Usefull to keep sysv libraries, binaries in /emul/ibcs2.
o many other finer details and functions fixed or implemented.


# 11395 10-Oct-1995 swallace

This commit was generated by cvs2svn to compensate for changes in r11394,
which included commits to RCS files with non-trunk default branches.


# 11394 10-Oct-1995 swallace

Import of original NetBSD's ibcs2 emulator sources by Scott Bartram,
which is used as a basis for a more complete and cleaner ibcs2 emulator.
(snapshot about May 1995 with a few files from September 1995)

Some files and code from old emulator still remains.
New files, features, and changes have been implemented by myself,
which will be shown in following commits.