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linux-next/arch/h8300
David Howells ee18d64c1f KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]
Add a keyctl to install a process's session keyring onto its parent.  This
replaces the parent's session keyring.  Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again.  Normally this
will be after a wait*() syscall.

To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.

The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.

Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME.  This allows the
replacement to be performed at the point the parent process resumes userspace
execution.

This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership.  However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.

This can be tested with the following program:

	#include <stdio.h>
	#include <stdlib.h>
	#include <keyutils.h>

	#define KEYCTL_SESSION_TO_PARENT	18

	#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)

	int main(int argc, char **argv)
	{
		key_serial_t keyring, key;
		long ret;

		keyring = keyctl_join_session_keyring(argv[1]);
		OSERROR(keyring, "keyctl_join_session_keyring");

		key = add_key("user", "a", "b", 1, keyring);
		OSERROR(key, "add_key");

		ret = keyctl(KEYCTL_SESSION_TO_PARENT);
		OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");

		return 0;
	}

Compiled and linked with -lkeyutils, you should see something like:

	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: _ses
	355907932 --alswrv   4043    -1   \_ keyring: _uid.4043
	[dhowells@andromeda ~]$ /tmp/newpag
	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: _ses
	1055658746 --alswrv   4043  4043   \_ user: a
	[dhowells@andromeda ~]$ /tmp/newpag hello
	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: hello
	340417692 --alswrv   4043  4043   \_ user: a

Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02 21:29:22 +10:00
..
boot inflate: refactor inflate malloc code 2008-07-25 10:53:28 -07:00
include/asm KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #6] 2009-09-02 21:29:19 +10:00
kernel KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] 2009-09-02 21:29:22 +10:00
lib kbuild: fix AFLAGS use in h8300 and m68knommu 2007-10-15 21:03:59 +02:00
mm h8300: GENERIC_BUG support 2008-10-16 11:21:29 -07:00
platform h8300: update timer handler - delete files 2008-10-16 11:21:29 -07:00
defconfig h8300: defconfig update 2008-02-23 17:12:16 -08:00
Kconfig Staging: Kconfig for ARCH=arm,8300, cris 2009-01-06 13:51:38 -08:00
Kconfig.cpu h8/300: fix incorrect "select" directives in arch/h8300/Kconfig.cpu. 2009-06-23 12:50:05 -07:00
Kconfig.debug H8300: Typo: "buildin" -> "builtin" 2007-10-20 00:26:06 +02:00
Kconfig.ide Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
Makefile kbuild: enable 'make AFLAGS=...' to add additional options to AS 2007-10-15 21:59:31 +02:00
README Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00

linux-2.6 for H8/300 README
Yoshinori Sato <ysato@users.sourceforge.jp>

* Supported CPU
H8/300H and H8S

* Supported Target
1.simulator of GDB
  require patches.

2.AE 3068/AE 3069
  more information 
  MICROTRONIQUE <http://www.microtronique.com/>
  Akizuki Denshi Tsusho Ltd. <http://www.akizuki.ne.jp> (Japanese Only)

3.H8MAX 
  see http://ip-sol.jp/h8max/ (Japanese Only)

4.EDOSK2674
  see http://www.eu.renesas.com/products/mpumcu/tool/edk/support/edosk2674.html
      http://www.azpower.com/H8-uClinux/

* Toolchain Version
gcc-3.1 or higher and patch
see arch/h8300/tools_patch/README
binutils-2.12 or higher
gdb-5.2 or higher
The environment that can compile a h8300-elf binary is necessary.

* Userland Develop environment
used h8300-elf toolchains.
see http://www.uclinux.org/pub/uClinux/ports/h8/

* A few words of thanks
Porting to H8/300 serieses is support of Information-technology Promotion Agency, Japan.
I thank support.
and All developer/user.