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* TOMOYO: Remove wrapper function for reading keyword.Tetsuo Handa2010-08-021-4/+4
| | | | | | | Keyword strings are read-only. We can directly access them to reduce code size. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Rename symbols.Tetsuo Handa2010-08-021-22/+22
| | | | | | | Use shorter name in order to make it easier to fix 80 columns limit. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Use callback for updating entries.Tetsuo Handa2010-08-021-22/+13
| | | | | | | Use common code for elements using "struct list_head" + "bool" structure. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Use common structure for list element.Tetsuo Handa2010-08-021-9/+9
| | | | | | | Use common "struct list_head" + "bool" structure. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Use callback for updating entries.Tetsuo Handa2010-08-021-2/+2
| | | | | | | | Use common "struct list_head" + "bool" + "u8" structure and use common code for elements using that structure. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Update profile structure.Tetsuo Handa2010-08-021-172/+259
| | | | | | | | | | | | | | | | | | This patch allows users to change access control mode for per-operation basis. This feature comes from non LSM version of TOMOYO which is designed for permitting users to use SELinux and TOMOYO at the same time. SELinux does not care filename in a directory whereas TOMOYO does. Change of filename can change how the file is used. For example, renaming index.txt to .htaccess will change how the file is used. Thus, letting SELinux to enforce read()/write()/mmap() etc. restriction and letting TOMOYO to enforce rename() restriction is an example usage of this feature. What is unfortunate for me is that currently LSM does not allow users to use SELinux and LSM version of TOMOYO at the same time... Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add pathname aggregation support.Tetsuo Handa2010-08-021-0/+4
| | | | | | | | This patch allows users to aggregate programs which provide similar functionality (e.g. /usr/bin/vi and /usr/bin/emacs ). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Allow wildcard for execute permission.Tetsuo Handa2010-08-021-1/+1
| | | | | | | | | Some applications create and execute programs dynamically. We need to accept wildcard for execute permission because such programs contain random suffix in their filenames. This patch loosens up regulation of string parameters. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Several fixes for TOMOYO's management programs.Tetsuo Handa2010-08-021-5/+20
| | | | | Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Split files into some pieces.Tetsuo Handa2010-08-021-1120/+23
| | | | | | | security/tomoyo/common.c became too large to read. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add interactive enforcing mode.Tetsuo Handa2010-08-021-7/+419
| | | | | | | | | | | | | | | | | | | | | | | | | | | Since the behavior of the system is restricted by policy, we may need to update policy when you update packages. We need to update policy in the following cases. * The pathname of files has changed. * The dependency of files has changed. * The access permissions required has increased. The ideal way to update policy is to rebuild from the scratch using learning mode. But it is not desirable to change from enforcing mode to other mode if the system has once entered in production state. Suppose MAC could support per-application enforcing mode, the MAC becomes useless if an application that is not running in enforcing mode was cracked. For example, the whole system becomes vulnerable if only HTTP server application is running in learning mode to rebuild policy for the application. So, in TOMOYO Linux, updating policy is done while the system is running in enforcing mode. This patch implements "interactive enforcing mode" which allows administrators to judge whether to accept policy violation in enforcing mode or not. A demo movie is available at http://www.youtube.com/watch?v=b9q1Jo25LPA . Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add mount restriction.Tetsuo Handa2010-08-021-0/+35
| | | | | | | | mount(2) has three string and one numeric parameters. Split mount restriction code from security/tomoyo/file.c . Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Split file access control functions by type of parameters.Tetsuo Handa2010-08-021-5/+100
| | | | | | | | Check numeric parameters for operations that deal them (e.g. chmod/chown/ioctl). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Use structure for passing common arguments.Tetsuo Handa2010-08-021-17/+5
| | | | | | | Use "struct tomoyo_request_info" instead of passing individual arguments. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add numeric values grouping support.Tetsuo Handa2010-08-021-0/+161
| | | | | | | | This patch adds numeric values grouping support, which is useful for grouping numeric values such as file's UID, DAC's mode, ioctl()'s cmd number. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add pathname grouping support.Tetsuo Handa2010-05-171-13/+87
| | | | | | | | This patch adds pathname grouping support, which is useful for grouping pathnames that cannot be represented using /\{dir\}/ pattern. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Use stack memory for pending entry.Tetsuo Handa2010-05-101-18/+14
| | | | | | | Use stack memory for pending entry to reduce kmalloc() which will be kfree()d. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Use mutex_lock_interruptible.Tetsuo Handa2010-05-061-5/+8
| | | | | | | | | | Some of TOMOYO's functions may sleep after mutex_lock(). If OOM-killer selected a process which is waiting at mutex_lock(), the to-be-killed process can't be killed. Thus, replace mutex_lock() with mutex_lock_interruptible() so that the to-be-killed process can immediately return from TOMOYO's functions. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'master' into nextJames Morris2010-05-061-0/+1
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| * include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* | TOMOYO: Use GFP_NOFS rather than GFP_KERNEL.Tetsuo Handa2010-05-051-5/+5
| | | | | | | | | | | | | | | | | | In Ubuntu, security_path_*() hooks are exported to Unionfs. Thus, prepare for being called from inside VFS functions because I'm not sure whether it is safe to use GFP_KERNEL or not. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | Merge branch 'master' into nextJames Morris2010-03-301-0/+1
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| * tomoyo: fix potential use after freeDan Carpenter2010-03-141-0/+1
| | | | | | | | | | | | | | | | | | The original code returns a freed pointer. This function is expected to return NULL on errors. Signed-off-by: Dan Carpenter <error27@gmail.com> Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | Merge branch 'next-queue' into nextJames Morris2010-03-091-7/+3
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| * TOMOYO: Remove unused variables.Tetsuo Handa2010-03-021-7/+3
| | | | | | | | | | | | | | Variable "atmark" is currently unused. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Protect find_task_by_vpid() with RCU.Tetsuo Handa2010-02-251-0/+4
| | | | | | | | | | | | | | | | | | | | | | Holding tasklist_lock is no longer sufficient for find_task_by_vpid(). Explicit rcu_read_lock() is required. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> -- security/tomoyo/common.c | 4 ++++ 1 file changed, 4 insertions(+) Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Remove __func__ from tomoyo_is_correct_path/domainTetsuo Handa2010-02-171-14/+4
| | | | | | | | | | | | | | __func__ is used for only debug printk(). We can remove it. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Use shorter names.Tetsuo Handa2010-02-161-43/+31
| | | | | | | | | | | | | | Use shorter name to reduce newlines needed for 80 columns limit. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Add garbage collector.Tetsuo Handa2010-02-141-1/+4
| | | | | | | | | | | | | | | | | | This patch adds garbage collector support to TOMOYO. Elements are protected by "struct srcu_struct tomoyo_ss". Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Merge headers.Tetsuo Handa2010-02-141-23/+0
| | | | | | | | | | | | | | | | | | | | Gather structures and constants scattered around security/tomoyo/ directory. This is for preparation for adding garbage collector since garbage collector needs to know structures and constants which TOMOYO uses. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Add refcounter on string data.Tetsuo Handa2010-02-141-3/+7
| | | | | | | | | | | | | | | | | | | | Add refcounter to "struct tomoyo_name_entry" and replace tomoyo_save_name() with tomoyo_get_name()/tomoyo_put_name() pair so that we can kfree() when garbage collector is added. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Reduce lines by using common path for addition and deletion.Tetsuo Handa2010-02-111-16/+12
| | | | | | | | | | | | | | | | | | Since the codes for adding an entry and removing an entry are similar, we can save some lines by using "if (is_delete) { ... } else { ... }" branches. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Extract bitfieldTetsuo Handa2010-02-081-11/+5
| | | | | | | | | | | | | | | | | | Since list elements are rounded up to kmalloc() size rather than sizeof(int), saving one byte by using bitfields is no longer helpful. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Remove usage counter for temporary memory.Tetsuo Handa2010-01-261-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | TOMOYO was using own memory usage counter for detecting memory leak. But as kernel 2.6.31 introduced memory leak detection mechanism ( CONFIG_DEBUG_KMEMLEAK ), we no longer need to have own counter. We remove usage counter for memory used for permission checks, but we keep usage counter for memory used for policy so that we can apply quota. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Remove memory pool for list elements.Tetsuo Handa2010-01-101-33/+8
| | | | | | | | | | | | | | | | | | Currently, TOMOYO allocates memory for list elements from memory pool allocated by kmalloc(PAGE_SIZE). But that makes it difficult to kfree() when garbage collector is added. Thus, remove memory pool and use kmalloc(sizeof()). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Replace rw_semaphore by mutex.Tetsuo Handa2010-01-101-5/+7
| | | | | | | | | | | | | | | | | | | | Since readers no longer use down_read(), writers no longer need to use rw_semaphore. Replace individual rw_semaphore by single mutex. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Use RCU primitives for list operationTetsuo Handa2009-12-151-40/+50
| | | | | | | | | | | | | | | | | | Replace list operation with RCU primitives and replace down_read()/up_read() with srcu_read_lock()/srcu_read_unlock(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* | TOMOYO: Add rest of file operation restrictions.Tetsuo Handa2009-12-081-43/+18
|/ | | | | | | | LSM hooks for chmod()/chown()/chroot() are now ready. This patch utilizes these hooks. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add recursive directory matching operator support.Tetsuo Handa2009-11-251-79/+121
| | | | | | | | | | | | | | TOMOYO 1.7.1 has recursive directory matching operator support. I want to add it to TOMOYO for Linux 2.6.33 . ---------- [PATCH] TOMOYO: Add recursive directory matching operator support. This patch introduces new operator /\{dir\}/ which matches '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/ /dir/dir/dir/ ). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Move tomoyo_delete_domain().Tetsuo Handa2009-06-191-0/+30
| | | | | | | | We can mark tomoyo_delete_domain() as a "static" function by moving it from domain.c to common.c . Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Add description of lists and structures.Tetsuo Handa2009-06-091-5/+64
| | | | | | | | This patch adds some descriptions of lists and structures. This patch contains no code changes. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Remove unused field.Tetsuo Handa2009-06-091-1/+0
| | | | | | | TOMOYO 2.2.0 is not using total_len field of "struct tomoyo_path_info". Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Simplify policy reader.Tetsuo Handa2009-06-021-23/+18
| | | | | | | | | We can directly assign the result of tomoyo_io_printf() to done flag. Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Remove redundant markers.Tetsuo Handa2009-06-021-8/+0
| | | | | | | Remove '/***** START/STOP *****/' markers. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
* Reduce path_lookup() abusesAl Viro2009-05-091-3/+3
| | | | | | | | ... use kern_path() where possible [folded a fix from rdd] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* tomoyo: version bump to 2.2.0.Tetsuo Handa2009-04-141-3/+3
| | | | | | | Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp> Signed-off-by: James Morris <jmorris@namei.org>
* tomoyo: remove "undelete domain" command.Tetsuo Handa2009-04-071-6/+1
| | | | | | | | | | Since TOMOYO's policy management tools does not use the "undelete domain" command, we decided to remove that command. Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp> Signed-off-by: James Morris <jmorris@namei.org>
* TOMOYO: Don't create securityfs entries unless registered.Tetsuo Handa2009-02-151-0/+4
| | | | | | | | | | TOMOYO should not create /sys/kernel/security/tomoyo/ interface unless TOMOYO is registered. Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp> Signed-off-by: James Morris <jmorris@namei.org>
* Common functions for TOMOYO Linux.Kentaro Takeda2009-02-121-0/+2202
This file contains common functions (e.g. policy I/O, pattern matching). -------------------- About pattern matching -------------------- Since TOMOYO Linux is a name based access control, TOMOYO Linux seriously considers "safe" string representation. TOMOYO Linux's string manipulation functions make reviewers feel crazy, but there are reasons why TOMOYO Linux needs its own string manipulation functions. ----- Part 1 : preconditions ----- People definitely want to use wild card. To support pattern matching, we have to support wild card characters. In a typical Linux system, filenames are likely consists of only alphabets, numbers, and some characters (e.g. + - ~ . / ). But theoretically, the Linux kernel accepts all characters but NUL character (which is used as a terminator of a string). Some Linux systems can have filenames which contain * ? ** etc. Therefore, we have to somehow modify string so that we can distinguish wild card characters and normal characters. It might be possible for some application's configuration files to restrict acceptable characters. It is impossible for kernel to restrict acceptable characters. We can't accept approaches which will cause troubles for applications. ----- Part 2 : commonly used approaches ----- Text formatted strings separated by space character (0x20) and new line character (0x0A) is more preferable for users over array of NUL-terminated string. Thus, people use text formatted configuration files separated by space character and new line. We sometimes need to handle non-printable characters. Thus, people use \ character (0x5C) as escape character and represent non-printable characters using octal or hexadecimal format. At this point, we remind (at least) 3 approaches. (1) Shell glob style expression (2) POSIX regular expression (UNIX style regular expression) (3) Maverick wild card expression On the surface, (1) and (2) sound good choices. But they have a big pitfall. All meta-characters in (1) and (2) are legal characters for representing a pathname, and users easily write incorrect expression. What is worse, users unlikely notice incorrect expressions because characters used for regular pathnames unlikely contain meta-characters. This incorrect use of meta-characters in pathname representation reveals vulnerability (e.g. unexpected results) only when irregular pathname is specified. The authors of TOMOYO Linux think that approaches which adds some character for interpreting meta-characters as normal characters (i.e. (1) and (2)) are not suitable for security use. Therefore, the authors of TOMOYO Linux propose (3). ----- Part 3: consideration points ----- We need to solve encoding problem. A single character can be represented in several ways using encodings. For Japanese language, there are "ShiftJIS", "ISO-2022-JP", "EUC-JP", "UTF-8" and more. Some languages (e.g. Japanese language) supports multi-byte characters (where a single character is represented using several bytes). Some multi-byte characters may match the escape character. For Japanese language, some characters in "ShiftJIS" encoding match \ character, and bothering Web's CGI developers. It is important that the kernel string is not bothered by encoding problem. Linus said, "I really would expect that kernel strings don't have an encoding. They're just C strings: a NUL-terminated stream of bytes." http://lkml.org/lkml/2007/11/6/142 Yes. The kernel strings are just C strings. We are talking about how to store and carry "kernel strings" safely. If we store "kernel string" into policy file as-is, the "kernel string" will be interpreted differently depending on application's encoding settings. One application may interpret "kernel string" as "UTF-8", another application may interpret "kernel string" as "ShiftJIS". Therefore, we propose to represent strings using ASCII encoding. In this way, we are no longer bothered by encoding problems. We need to avoid information loss caused by display. It is difficult to input and display non-printable characters, but we have to be able to handle such characters because the kernel string is a C string. If we use only ASCII printable characters (from 0x21 to 0x7E) and space character (0x20) and new line character (0x0A), it is easy to input from keyboard and display on all terminals which is running Linux. Therefore, we propose to represent strings using only characters which value is one of "from 0x21 to 0x7E", "0x20", "0x0A". We need to consider ease of splitting strings from a line. If we use an approach which uses "\ " for representing a space character within a string, we have to count the string from the beginning to check whether this space character is accompanied with \ character or not. As a result, we cannot monotonically split a line using space character. If we use an approach which uses "\040" for representing a space character within a string, we can monotonically split a line using space character. If we use an approach which uses NUL character as a delimiter, we cannot use string manipulation functions for splitting strings from a line. Therefore, we propose that we represent space character as "\040". We need to avoid wrong designations (incorrect use of special characters). Not all users can understand and utilize POSIX's regular expressions correctly and perfectly. If a character acts as a wild card by default, the user will get unexpected result if that user didn't know the meaning of that character. Therefore, we propose that all characters but \ character act as a normal character and let the user add \ character to make a character act as a wild card. In this way, users needn't to know all wild card characters beforehand. They can learn when they encountered an unseen wild card character for their first time. ----- Part 4: supported wild card expressions ----- At this point, we have wild card expressions listed below. +-----------+--------------------------------------------------------------+ | Wild card | Meaning and example | +-----------+--------------------------------------------------------------+ | \* | More than or equals to 0 character other than '/'. | | | /var/log/samba/\* | +-----------+--------------------------------------------------------------+ | \@ | More than or equals to 0 character other than '/' or '.'. | | | /var/www/html/\@.html | +-----------+--------------------------------------------------------------+ | \? | 1 byte character other than '/'. | | | /tmp/mail.\?\?\?\?\?\? | +-----------+--------------------------------------------------------------+ | \$ | More than or equals to 1 decimal digit. | | | /proc/\$/cmdline | +-----------+--------------------------------------------------------------+ | \+ | 1 decimal digit. | | | /var/tmp/my_work.\+ | +-----------+--------------------------------------------------------------+ | \X | More than or equals to 1 hexadecimal digit. | | | /var/tmp/my-work.\X | +-----------+--------------------------------------------------------------+ | \x | 1 hexadecimal digit. | | | /tmp/my-work.\x | +-----------+--------------------------------------------------------------+ | \A | More than or equals to 1 alphabet character. | | | /var/log/my-work/\$-\A-\$.log | +-----------+--------------------------------------------------------------+ | \a | 1 alphabet character. | | | /home/users/\a/\*/public_html/\*.html | +-----------+--------------------------------------------------------------+ | \- | Pathname subtraction operator. | | | +---------------------+------------------------------------+ | | | | Example | Meaning | | | | +---------------------+------------------------------------+ | | | | /etc/\* | All files in /etc/ directory. | | | | +---------------------+------------------------------------+ | | | | /etc/\*\-\*shadow\* | /etc/\* other than /etc/\*shadow\* | | | | +---------------------+------------------------------------+ | | | | /\*\-proc\-sys/ | /\*/ other than /proc/ /sys/ | | | | +---------------------+------------------------------------+ | +-----------+--------------------------------------------------------------+ +----------------+---------------------------------------------------------+ | Representation | Meaning and example | +----------------+---------------------------------------------------------+ | \\ | backslash character itself. | +----------------+---------------------------------------------------------+ | \ooo | 1 byte character. | | | ooo is 001 <= ooo <= 040 || 177 <= ooo <= 377. | | | | | | \040 for space character. | | | \177 for del character. | | | | +----------------+---------------------------------------------------------+ ----- Part 5: Advantages ----- We can obtain extensibility. Since our proposed approach adds \ to a character to interpret as a wild card, we can introduce new wild card in future while maintaining backward compatibility. We can process monotonically. Since our proposed approach separates strings using a space character, we can split strings using existing string manipulation functions. We can reliably analyze access logs. It is guaranteed that a string doesn't contain space character (0x20) and new line character (0x0A). It is guaranteed that a string won't be converted by FTP and won't be damaged by a terminal's settings. It is guaranteed that a string won't be affected by encoding converters (except encodings which insert NUL character (e.g. UTF-16)). ----- Part 6: conclusion ----- TOMOYO Linux is using its own encoding with reasons described above. There is a disadvantage that we need to introduce a series of new string manipulation functions. But TOMOYO Linux's encoding is useful for all users (including audit and AppArmor) who want to perform pattern matching and safely exchange string information between the kernel and the userspace. -------------------- About policy interface -------------------- TOMOYO Linux creates the following files on securityfs (normally mounted on /sys/kernel/security) as interfaces between kernel and userspace. These files are for TOMOYO Linux management tools *only*, not for general programs. * profile * exception_policy * domain_policy * manager * meminfo * self_domain * version * .domain_status * .process_status ** /sys/kernel/security/tomoyo/profile ** This file is used to read or write profiles. "profile" means a running mode of process. A profile lists up functions and their modes in "$number-$variable=$value" format. The $number is profile number between 0 and 255. Each domain is assigned one profile. To assign profile to domains, use "ccs-setprofile" or "ccs-editpolicy" or "ccs-loadpolicy" commands. (Example) [root@tomoyo]# cat /sys/kernel/security/tomoyo/profile 0-COMMENT=-----Disabled Mode----- 0-MAC_FOR_FILE=disabled 0-MAX_ACCEPT_ENTRY=2048 0-TOMOYO_VERBOSE=disabled 1-COMMENT=-----Learning Mode----- 1-MAC_FOR_FILE=learning 1-MAX_ACCEPT_ENTRY=2048 1-TOMOYO_VERBOSE=disabled 2-COMMENT=-----Permissive Mode----- 2-MAC_FOR_FILE=permissive 2-MAX_ACCEPT_ENTRY=2048 2-TOMOYO_VERBOSE=enabled 3-COMMENT=-----Enforcing Mode----- 3-MAC_FOR_FILE=enforcing 3-MAX_ACCEPT_ENTRY=2048 3-TOMOYO_VERBOSE=enabled - MAC_FOR_FILE: Specifies access control level regarding file access requests. - MAX_ACCEPT_ENTRY: Limits the max number of ACL entries that are automatically appended during learning mode. Default is 2048. - TOMOYO_VERBOSE: Specifies whether to print domain policy violation messages or not. ** /sys/kernel/security/tomoyo/manager ** This file is used to read or append the list of programs or domains that can write to /sys/kernel/security/tomoyo interface. By default, only processes with both UID = 0 and EUID = 0 can modify policy via /sys/kernel/security/tomoyo interface. You can use keyword "manage_by_non_root" to allow policy modification by non root user. (Example) [root@tomoyo]# cat /sys/kernel/security/tomoyo/manager /usr/lib/ccs/loadpolicy /usr/lib/ccs/editpolicy /usr/lib/ccs/setlevel /usr/lib/ccs/setprofile /usr/lib/ccs/ld-watch /usr/lib/ccs/ccs-queryd ** /sys/kernel/security/tomoyo/exception_policy ** This file is used to read and write system global settings. Each line has a directive and operand pair. Directives are listed below. - initialize_domain: To initialize domain transition when specific program is executed, use initialize_domain directive. * initialize_domain "program" from "domain" * initialize_domain "program" from "the last program part of domain" * initialize_domain "program" If the part "from" and after is not given, the entry is applied to all domain. If the "domain" doesn't start with "<kernel>", the entry is applied to all domain whose domainname ends with "the last program part of domain". This directive is intended to aggregate domain transitions for daemon program and program that are invoked by the kernel on demand, by transiting to different domain. - keep_domain To prevent domain transition when program is executed from specific domain, use keep_domain directive. * keep_domain "program" from "domain" * keep_domain "program" from "the last program part of domain" * keep_domain "domain" * keep_domain "the last program part of domain" If the part "from" and before is not given, this entry is applied to all program. If the "domain" doesn't start with "<kernel>", the entry is applied to all domain whose domainname ends with "the last program part of domain". This directive is intended to reduce total number of domains and memory usage by suppressing unneeded domain transitions. To declare domain keepers, use keep_domain directive followed by domain definition. Any process that belongs to any domain declared with this directive, the process stays at the same domain unless any program registered with initialize_domain directive is executed. In order to control domain transition in detail, you can use no_keep_domain/no_initialize_domain keywrods. - alias: To allow executing programs using the name of symbolic links, use alias keyword followed by dereferenced pathname and reference pathname. For example, /sbin/pidof is a symbolic link to /sbin/killall5 . In normal case, if /sbin/pidof is executed, the domain is defined as if /sbin/killall5 is executed. By specifying "alias /sbin/killall5 /sbin/pidof", you can run /sbin/pidof in the domain for /sbin/pidof . (Example) alias /sbin/killall5 /sbin/pidof - allow_read: To grant unconditionally readable permissions, use allow_read keyword followed by canonicalized file. This keyword is intended to reduce size of domain policy by granting read access to library files such as GLIBC and locale files. Exception is, if ignore_global_allow_read keyword is given to a domain, entries specified by this keyword are ignored. (Example) allow_read /lib/libc-2.5.so - file_pattern: To declare pathname pattern, use file_pattern keyword followed by pathname pattern. The pathname pattern must be a canonicalized Pathname. This keyword is not applicable to neither granting execute permissions nor domain definitions. For example, canonicalized pathname that contains a process ID (i.e. /proc/PID/ files) needs to be grouped in order to make access control work well. (Example) file_pattern /proc/\$/cmdline - path_group To declare pathname group, use path_group keyword followed by name of the group and pathname pattern. For example, if you want to group all files under home directory, you can define path_group HOME-DIR-FILE /home/\*/\* path_group HOME-DIR-FILE /home/\*/\*/\* path_group HOME-DIR-FILE /home/\*/\*/\*/\* in the exception policy and use like allow_read @HOME-DIR-FILE to grant file access permission. - deny_rewrite: To deny overwriting already written contents of file (such as log files) by default, use deny_rewrite keyword followed by pathname pattern. Files whose pathname match the patterns are not permitted to open for writing without append mode or truncate unless the pathnames are explicitly granted using allow_rewrite keyword in domain policy. (Example) deny_rewrite /var/log/\* - aggregator To deal multiple programs as a single program, use aggregator keyword followed by name of original program and aggregated program. This keyword is intended to aggregate similar programs. For example, /usr/bin/tac and /bin/cat are similar. By specifying "aggregator /usr/bin/tac /bin/cat", you can run /usr/bin/tac in the domain for /bin/cat . For example, /usr/sbin/logrotate for Fedora Core 3 generates programs like /tmp/logrotate.\?\?\?\?\?\? and run them, but TOMOYO Linux doesn't allow using patterns for granting execute permission and defining domains. By specifying "aggregator /tmp/logrotate.\?\?\?\?\?\? /tmp/logrotate.tmp", you can run /tmp/logrotate.\?\?\?\?\?\? as if /tmp/logrotate.tmp is running. ** /sys/kernel/security/tomoyo/domain_policy ** This file contains definition of all domains and permissions that are granted to each domain. Lines from the next line to a domain definition ( any lines starting with "<kernel>") to the previous line to the next domain definitions are interpreted as access permissions for that domain. ** /sys/kernel/security/tomoyo/meminfo ** This file is to show the total RAM used to keep policy in the kernel by TOMOYO Linux in bytes. (Example) [root@tomoyo]# cat /sys/kernel/security/tomoyo/meminfo Shared: 61440 Private: 69632 Dynamic: 768 Total: 131840 You can set memory quota by writing to this file. (Example) [root@tomoyo]# echo Shared: 2097152 > /sys/kernel/security/tomoyo/meminfo [root@tomoyo]# echo Private: 2097152 > /sys/kernel/security/tomoyo/meminfo ** /sys/kernel/security/tomoyo/self_domain ** This file is to show the name of domain the caller process belongs to. (Example) [root@etch]# cat /sys/kernel/security/tomoyo/self_domain <kernel> /usr/sbin/sshd /bin/zsh /bin/cat ** /sys/kernel/security/tomoyo/version ** This file is used for getting TOMOYO Linux's version. (Example) [root@etch]# cat /sys/kernel/security/tomoyo/version 2.2.0-pre ** /sys/kernel/security/tomoyo/.domain_status ** This is a view (of a DBMS) that contains only profile number and domainnames of domain so that "ccs-setprofile" command can do line-oriented processing easily. ** /sys/kernel/security/tomoyo/.process_status ** This file is used by "ccs-ccstree" command to show "list of processes currently running" and "domains which each process belongs to" and "profile number which the domain is currently assigned" like "pstree" command. This file is writable by programs that aren't registered as policy manager. Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp> Signed-off-by: James Morris <jmorris@namei.org>