[linux-2.6-block.git] / kernel / capability.c

/*
 * linux/kernel/capability.c
 *
 * Copyright (C) 1997  Andrew Main <zefram@fysh.org>
 *
 * Integrated into 2.1.97+,  Andrew G. Morgan <morgan@kernel.org>
 * 30 May 2002:	Cleanup, Robert M. Love <rml@tech9.net>
 */

#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/pid_namespace.h>
#include <asm/uaccess.h>

/*
 * This lock protects task->cap_* for all tasks including current.
 * Locking rule: acquire this prior to tasklist_lock.
 */
static DEFINE_SPINLOCK(task_capability_lock);

/*
 * Leveraged for setting/resetting capabilities
 */

const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET;
const kernel_cap_t __cap_full_set = CAP_FULL_SET;
const kernel_cap_t __cap_init_eff_set = CAP_INIT_EFF_SET;

EXPORT_SYMBOL(__cap_empty_set);
EXPORT_SYMBOL(__cap_full_set);
EXPORT_SYMBOL(__cap_init_eff_set);

/*
 * More recent versions of libcap are available from:
 *
 *   http://www.kernel.org/pub/linux/libs/security/linux-privs/
 */

static void warn_legacy_capability_use(void)
{
	static int warned;
	if (!warned) {
		char name[sizeof(current->comm)];

		printk(KERN_INFO "warning: `%s' uses 32-bit capabilities"
		       " (legacy support in use)\n",
		       get_task_comm(name, current));
		warned = 1;
	}
}

/*
 * Version 2 capabilities worked fine, but the linux/capability.h file
 * that accompanied their introduction encouraged their use without
 * the necessary user-space source code changes. As such, we have
 * created a version 3 with equivalent functionality to version 2, but
 * with a header change to protect legacy source code from using
 * version 2 when it wanted to use version 1. If your system has code
 * that trips the following warning, it is using version 2 specific
 * capabilities and may be doing so insecurely.
 *
 * The remedy is to either upgrade your version of libcap (to 2.10+,
 * if the application is linked against it), or recompile your
 * application with modern kernel headers and this warning will go
 * away.
 */

static void warn_deprecated_v2(void)
{
	static int warned;

	if (!warned) {
		char name[sizeof(current->comm)];

		printk(KERN_INFO "warning: `%s' uses deprecated v2"
		       " capabilities in a way that may be insecure.\n",
		       get_task_comm(name, current));
		warned = 1;
	}
}

/*
 * Version check. Return the number of u32s in each capability flag
 * array, or a negative value on error.
 */
static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
{
	__u32 version;

	if (get_user(version, &header->version))
		return -EFAULT;

	switch (version) {
	case _LINUX_CAPABILITY_VERSION_1:
		warn_legacy_capability_use();
		*tocopy = _LINUX_CAPABILITY_U32S_1;
		break;
	case _LINUX_CAPABILITY_VERSION_2:
		warn_deprecated_v2();
		/*
		 * fall through - v3 is otherwise equivalent to v2.
		 */
	case _LINUX_CAPABILITY_VERSION_3:
		*tocopy = _LINUX_CAPABILITY_U32S_3;
		break;
	default:
		if (put_user((u32)_KERNEL_CAPABILITY_VERSION, &header->version))
			return -EFAULT;
		return -EINVAL;
	}

	return 0;
}

/*
 * For sys_getproccap() and sys_setproccap(), any of the three
 * capability set pointers may be NULL -- indicating that that set is
 * uninteresting and/or not to be changed.
 */

/**
 * sys_capget - get the capabilities of a given process.
 * @header: pointer to struct that contains capability version and
 *	target pid data
 * @dataptr: pointer to struct that contains the effective, permitted,
 *	and inheritable capabilities that are returned
 *
 * Returns 0 on success and < 0 on error.
 */
asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
{
	int ret = 0;
	pid_t pid;
	struct task_struct *target;
	unsigned tocopy;
	kernel_cap_t pE, pI, pP;

	ret = cap_validate_magic(header, &tocopy);
	if (ret != 0)
		return ret;

	if (get_user(pid, &header->pid))
		return -EFAULT;

	if (pid < 0)
		return -EINVAL;

	spin_lock(&task_capability_lock);
	read_lock(&tasklist_lock);

	if (pid && pid != task_pid_vnr(current)) {
		target = find_task_by_vpid(pid);
		if (!target) {
			ret = -ESRCH;
			goto out;
		}
	} else
		target = current;

	ret = security_capget(target, &pE, &pI, &pP);

out:
	read_unlock(&tasklist_lock);
	spin_unlock(&task_capability_lock);

	if (!ret) {
		struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
		unsigned i;

		for (i = 0; i < tocopy; i++) {
			kdata[i].effective = pE.cap[i];
			kdata[i].permitted = pP.cap[i];
			kdata[i].inheritable = pI.cap[i];
		}

		/*
		 * Note, in the case, tocopy < _KERNEL_CAPABILITY_U32S,
		 * we silently drop the upper capabilities here. This
		 * has the effect of making older libcap
		 * implementations implicitly drop upper capability
		 * bits when they perform a: capget/modify/capset
		 * sequence.
		 *
		 * This behavior is considered fail-safe
		 * behavior. Upgrading the application to a newer
		 * version of libcap will enable access to the newer
		 * capabilities.
		 *
		 * An alternative would be to return an error here
		 * (-ERANGE), but that causes legacy applications to
		 * unexpectidly fail; the capget/modify/capset aborts
		 * before modification is attempted and the application
		 * fails.
		 */

		if (copy_to_user(dataptr, kdata, tocopy
				 * sizeof(struct __user_cap_data_struct))) {
			return -EFAULT;
		}
	}

	return ret;
}

/*
 * cap_set_pg - set capabilities for all processes in a given process
 * group.  We call this holding task_capability_lock and tasklist_lock.
 */
static inline int cap_set_pg(int pgrp_nr, kernel_cap_t *effective,
			      kernel_cap_t *inheritable,
			      kernel_cap_t *permitted)
{
	struct task_struct *g, *target;
	int ret = -EPERM;
	int found = 0;
	struct pid *pgrp;

	pgrp = find_vpid(pgrp_nr);
	do_each_pid_task(pgrp, PIDTYPE_PGID, g) {
		target = g;
		while_each_thread(g, target) {
			if (!security_capset_check(target, effective,
							inheritable,
							permitted)) {
				security_capset_set(target, effective,
							inheritable,
							permitted);
				ret = 0;
			}
			found = 1;
		}
	} while_each_pid_task(pgrp, PIDTYPE_PGID, g);

	if (!found)
		ret = 0;
	return ret;
}

/*
 * cap_set_all - set capabilities for all processes other than init
 * and self.  We call this holding task_capability_lock and tasklist_lock.
 */
static inline int cap_set_all(kernel_cap_t *effective,
			       kernel_cap_t *inheritable,
			       kernel_cap_t *permitted)
{
     struct task_struct *g, *target;
     int ret = -EPERM;
     int found = 0;

     do_each_thread(g, target) {
             if (target == current || is_container_init(target->group_leader))
                     continue;
             found = 1;
	     if (security_capset_check(target, effective, inheritable,
						permitted))
		     continue;
	     ret = 0;
	     security_capset_set(target, effective, inheritable, permitted);
     } while_each_thread(g, target);

     if (!found)
	     ret = 0;
     return ret;
}

/**
 * sys_capset - set capabilities for a process or a group of processes
 * @header: pointer to struct that contains capability version and
 *	target pid data
 * @data: pointer to struct that contains the effective, permitted,
 *	and inheritable capabilities
 *
 * Set capabilities for a given process, all processes, or all
 * processes in a given process group.
 *
 * The restrictions on setting capabilities are specified as:
 *
 * [pid is for the 'target' task.  'current' is the calling task.]
 *
 * I: any raised capabilities must be a subset of the (old current) permitted
 * P: any raised capabilities must be a subset of the (old current) permitted
 * E: must be set to a subset of (new target) permitted
 *
 * Returns 0 on success and < 0 on error.
 */
asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
{
	struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
	unsigned i, tocopy;
	kernel_cap_t inheritable, permitted, effective;
	struct task_struct *target;
	int ret;
	pid_t pid;

	ret = cap_validate_magic(header, &tocopy);
	if (ret != 0)
		return ret;

	if (get_user(pid, &header->pid))
		return -EFAULT;

	if (pid && pid != task_pid_vnr(current) && !capable(CAP_SETPCAP))
		return -EPERM;

	if (copy_from_user(&kdata, data, tocopy
			   * sizeof(struct __user_cap_data_struct))) {
		return -EFAULT;
	}

	for (i = 0; i < tocopy; i++) {
		effective.cap[i] = kdata[i].effective;
		permitted.cap[i] = kdata[i].permitted;
		inheritable.cap[i] = kdata[i].inheritable;
	}
	while (i < _KERNEL_CAPABILITY_U32S) {
		effective.cap[i] = 0;
		permitted.cap[i] = 0;
		inheritable.cap[i] = 0;
		i++;
	}

	spin_lock(&task_capability_lock);
	read_lock(&tasklist_lock);

	if (pid > 0 && pid != task_pid_vnr(current)) {
		target = find_task_by_vpid(pid);
		if (!target) {
			ret = -ESRCH;
			goto out;
		}
	} else
		target = current;

	ret = 0;

	/* having verified that the proposed changes are legal,
	   we now put them into effect. */
	if (pid < 0) {
		if (pid == -1)	/* all procs other than current and init */
			ret = cap_set_all(&effective, &inheritable, &permitted);

		else		/* all procs in process group */
			ret = cap_set_pg(-pid, &effective, &inheritable,
					 &permitted);
	} else {
		ret = security_capset_check(target, &effective, &inheritable,
					    &permitted);
		if (!ret)
			security_capset_set(target, &effective, &inheritable,
					    &permitted);
	}

out:
	read_unlock(&tasklist_lock);
	spin_unlock(&task_capability_lock);

	return ret;
}

int __capable(struct task_struct *t, int cap)
{
	if (security_capable(t, cap) == 0) {
		t->flags |= PF_SUPERPRIV;
		return 1;
	}
	return 0;
}

int capable(int cap)
{
	return __capable(current, cap);
}
EXPORT_SYMBOL(capable);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/kernel/capability.c
	3	*
	4	* Copyright (C) 1997 Andrew Main <zefram@fysh.org>
	5	*
72c2d582	6	* Integrated into 2.1.97+, Andrew G. Morgan <morgan@kernel.org>
1da177e4	7	* 30 May 2002: Cleanup, Robert M. Love <rml@tech9.net>
314f70fd	8	*/
1da177e4	9
c59ede7b	10	#include <linux/capability.h>
1da177e4 LT	11	#include <linux/mm.h>
	12	#include <linux/module.h>
	13	#include <linux/security.h>
	14	#include <linux/syscalls.h>
b460cbc5	15	#include <linux/pid_namespace.h>
1da177e4 LT	16	#include <asm/uaccess.h>
1da177e4 LT	17
1da177e4 LT	18	/*
	19	* This lock protects task->cap_* for all tasks including current.
	20	* Locking rule: acquire this prior to tasklist_lock.
	21	*/
	22	static DEFINE_SPINLOCK(task_capability_lock);
	23
e338d263 AM	24	/*
	25	* Leveraged for setting/resetting capabilities
	26	*/
	27
	28	const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET;
	29	const kernel_cap_t __cap_full_set = CAP_FULL_SET;
	30	const kernel_cap_t __cap_init_eff_set = CAP_INIT_EFF_SET;
	31
	32	EXPORT_SYMBOL(__cap_empty_set);
	33	EXPORT_SYMBOL(__cap_full_set);
	34	EXPORT_SYMBOL(__cap_init_eff_set);
	35
	36	/*
	37	* More recent versions of libcap are available from:
	38	*
	39	* http://www.kernel.org/pub/linux/libs/security/linux-privs/
	40	*/
	41
	42	static void warn_legacy_capability_use(void)
	43	{
	44	static int warned;
	45	if (!warned) {
	46	char name[sizeof(current->comm)];
	47
	48	printk(KERN_INFO "warning: `%s' uses 32-bit capabilities"
	49	" (legacy support in use)\n",
	50	get_task_comm(name, current));
	51	warned = 1;
	52	}
	53	}
	54
ca05a99a AM	55	/*
	56	* Version 2 capabilities worked fine, but the linux/capability.h file
	57	* that accompanied their introduction encouraged their use without
	58	* the necessary user-space source code changes. As such, we have
	59	* created a version 3 with equivalent functionality to version 2, but
	60	* with a header change to protect legacy source code from using
	61	* version 2 when it wanted to use version 1. If your system has code
	62	* that trips the following warning, it is using version 2 specific
	63	* capabilities and may be doing so insecurely.
	64	*
	65	* The remedy is to either upgrade your version of libcap (to 2.10+,
	66	* if the application is linked against it), or recompile your
	67	* application with modern kernel headers and this warning will go
	68	* away.
	69	*/
	70
	71	static void warn_deprecated_v2(void)
	72	{
	73	static int warned;
	74
	75	if (!warned) {
	76	char name[sizeof(current->comm)];
	77
	78	printk(KERN_INFO "warning: `%s' uses deprecated v2"
	79	" capabilities in a way that may be insecure.\n",
	80	get_task_comm(name, current));
	81	warned = 1;
	82	}
	83	}
	84
	85	/*
	86	* Version check. Return the number of u32s in each capability flag
	87	* array, or a negative value on error.
	88	*/
	89	static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
	90	{
	91	__u32 version;
	92
	93	if (get_user(version, &header->version))
	94	return -EFAULT;
	95
	96	switch (version) {
	97	case _LINUX_CAPABILITY_VERSION_1:
	98	warn_legacy_capability_use();
	99	*tocopy = _LINUX_CAPABILITY_U32S_1;
	100	break;
	101	case _LINUX_CAPABILITY_VERSION_2:
	102	warn_deprecated_v2();
	103	/*
	104	* fall through - v3 is otherwise equivalent to v2.
	105	*/
	106	case _LINUX_CAPABILITY_VERSION_3:
	107	*tocopy = _LINUX_CAPABILITY_U32S_3;
	108	break;
	109	default:
	110	if (put_user((u32)_KERNEL_CAPABILITY_VERSION, &header->version))
	111	return -EFAULT;
	112	return -EINVAL;
	113	}
	114
	115	return 0;
	116	}
	117
1da177e4 LT	118	/*
	119	* For sys_getproccap() and sys_setproccap(), any of the three
	120	* capability set pointers may be NULL -- indicating that that set is
	121	* uninteresting and/or not to be changed.
	122	*/
	123
207a7ba8	124	/**
1da177e4	125	* sys_capget - get the capabilities of a given process.
207a7ba8 RD	126	* @header: pointer to struct that contains capability version and
	127	* target pid data
	128	* @dataptr: pointer to struct that contains the effective, permitted,
	129	* and inheritable capabilities that are returned
	130	*
	131	* Returns 0 on success and < 0 on error.
1da177e4 LT	132	*/
	133	asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
	134	{
314f70fd DW	135	int ret = 0;
314f70fd DW	136	pid_t pid;
314f70fd	137	struct task_struct *target;
e338d263 AM	138	unsigned tocopy;
e338d263 AM	139	kernel_cap_t pE, pI, pP;
314f70fd	140
ca05a99a AM	141	ret = cap_validate_magic(header, &tocopy);
	142	if (ret != 0)
	143	return ret;
1da177e4	144
314f70fd DW	145	if (get_user(pid, &header->pid))
314f70fd DW	146	return -EFAULT;
1da177e4	147
314f70fd DW	148	if (pid < 0)
314f70fd DW	149	return -EINVAL;
1da177e4	150
314f70fd DW	151	spin_lock(&task_capability_lock);
314f70fd DW	152	read_lock(&tasklist_lock);
1da177e4	153
b488893a	154	if (pid && pid != task_pid_vnr(current)) {
228ebcbe	155	target = find_task_by_vpid(pid);
314f70fd DW	156	if (!target) {
	157	ret = -ESRCH;
	158	goto out;
	159	}
	160	} else
	161	target = current;
1da177e4	162
e338d263	163	ret = security_capget(target, &pE, &pI, &pP);
1da177e4 LT	164
1da177e4 LT	165	out:
314f70fd DW	166	read_unlock(&tasklist_lock);
314f70fd DW	167	spin_unlock(&task_capability_lock);
1da177e4	168
e338d263	169	if (!ret) {
ca05a99a	170	struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
e338d263 AM	171	unsigned i;
	172
	173	for (i = 0; i < tocopy; i++) {
	174	kdata[i].effective = pE.cap[i];
	175	kdata[i].permitted = pP.cap[i];
	176	kdata[i].inheritable = pI.cap[i];
	177	}
	178
	179	/*
ca05a99a	180	* Note, in the case, tocopy < _KERNEL_CAPABILITY_U32S,
e338d263 AM	181	* we silently drop the upper capabilities here. This
	182	* has the effect of making older libcap
	183	* implementations implicitly drop upper capability
	184	* bits when they perform a: capget/modify/capset
	185	* sequence.
	186	*
	187	* This behavior is considered fail-safe
	188	* behavior. Upgrading the application to a newer
	189	* version of libcap will enable access to the newer
	190	* capabilities.
	191	*
	192	* An alternative would be to return an error here
	193	* (-ERANGE), but that causes legacy applications to
	194	* unexpectidly fail; the capget/modify/capset aborts
	195	* before modification is attempted and the application
	196	* fails.
	197	*/
	198
	199	if (copy_to_user(dataptr, kdata, tocopy
	200	* sizeof(struct __user_cap_data_struct))) {
	201	return -EFAULT;
	202	}
	203	}
1da177e4	204
314f70fd	205	return ret;
1da177e4 LT	206	}
	207
	208	/*
	209	* cap_set_pg - set capabilities for all processes in a given process
	210	* group. We call this holding task_capability_lock and tasklist_lock.
	211	*/
41487c65	212	static inline int cap_set_pg(int pgrp_nr, kernel_cap_t *effective,
1da177e4 LT	213	kernel_cap_t *inheritable,
	214	kernel_cap_t *permitted)
	215	{
36c8b586	216	struct task_struct g, target;
1da177e4 LT	217	int ret = -EPERM;
1da177e4 LT	218	int found = 0;
41487c65	219	struct pid *pgrp;
1da177e4	220
8990571e	221	pgrp = find_vpid(pgrp_nr);
41487c65	222	do_each_pid_task(pgrp, PIDTYPE_PGID, g) {
1da177e4 LT	223	target = g;
	224	while_each_thread(g, target) {
	225	if (!security_capset_check(target, effective,
	226	inheritable,
	227	permitted)) {
	228	security_capset_set(target, effective,
	229	inheritable,
	230	permitted);
	231	ret = 0;
	232	}
	233	found = 1;
	234	}
41487c65	235	} while_each_pid_task(pgrp, PIDTYPE_PGID, g);
1da177e4 LT	236
1da177e4 LT	237	if (!found)
314f70fd	238	ret = 0;
1da177e4 LT	239	return ret;
	240	}
	241
	242	/*
	243	* cap_set_all - set capabilities for all processes other than init
	244	* and self. We call this holding task_capability_lock and tasklist_lock.
	245	*/
	246	static inline int cap_set_all(kernel_cap_t *effective,
	247	kernel_cap_t *inheritable,
	248	kernel_cap_t *permitted)
	249	{
36c8b586	250	struct task_struct g, target;
1da177e4 LT	251	int ret = -EPERM;
	252	int found = 0;
	253
	254	do_each_thread(g, target) {
b460cbc5	255	if (target == current \|\| is_container_init(target->group_leader))
1da177e4 LT	256	continue;
	257	found = 1;
	258	if (security_capset_check(target, effective, inheritable,
	259	permitted))
	260	continue;
	261	ret = 0;
	262	security_capset_set(target, effective, inheritable, permitted);
	263	} while_each_thread(g, target);
	264
	265	if (!found)
	266	ret = 0;
	267	return ret;
	268	}
	269
207a7ba8 RD	270	/**
	271	* sys_capset - set capabilities for a process or a group of processes
	272	* @header: pointer to struct that contains capability version and
	273	* target pid data
	274	* @data: pointer to struct that contains the effective, permitted,
	275	* and inheritable capabilities
	276	*
	277	* Set capabilities for a given process, all processes, or all
1da177e4 LT	278	* processes in a given process group.
	279	*
	280	* The restrictions on setting capabilities are specified as:
	281	*
	282	* [pid is for the 'target' task. 'current' is the calling task.]
	283	*
	284	* I: any raised capabilities must be a subset of the (old current) permitted
	285	* P: any raised capabilities must be a subset of the (old current) permitted
	286	* E: must be set to a subset of (new target) permitted
207a7ba8 RD	287	*
207a7ba8 RD	288	* Returns 0 on success and < 0 on error.
1da177e4 LT	289	*/
	290	asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
	291	{
ca05a99a	292	struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
e338d263	293	unsigned i, tocopy;
314f70fd	294	kernel_cap_t inheritable, permitted, effective;
314f70fd DW	295	struct task_struct *target;
	296	int ret;
	297	pid_t pid;
	298
ca05a99a AM	299	ret = cap_validate_magic(header, &tocopy);
	300	if (ret != 0)
	301	return ret;
314f70fd DW	302
	303	if (get_user(pid, &header->pid))
	304	return -EFAULT;
	305
b488893a	306	if (pid && pid != task_pid_vnr(current) && !capable(CAP_SETPCAP))
314f70fd DW	307	return -EPERM;
314f70fd DW	308
e338d263 AM	309	if (copy_from_user(&kdata, data, tocopy
e338d263 AM	310	* sizeof(struct __user_cap_data_struct))) {
314f70fd	311	return -EFAULT;
e338d263 AM	312	}
	313
	314	for (i = 0; i < tocopy; i++) {
	315	effective.cap[i] = kdata[i].effective;
	316	permitted.cap[i] = kdata[i].permitted;
	317	inheritable.cap[i] = kdata[i].inheritable;
	318	}
ca05a99a	319	while (i < _KERNEL_CAPABILITY_U32S) {
e338d263 AM	320	effective.cap[i] = 0;
	321	permitted.cap[i] = 0;
	322	inheritable.cap[i] = 0;
	323	i++;
	324	}
314f70fd DW	325
	326	spin_lock(&task_capability_lock);
	327	read_lock(&tasklist_lock);
	328
b488893a	329	if (pid > 0 && pid != task_pid_vnr(current)) {
228ebcbe	330	target = find_task_by_vpid(pid);
314f70fd DW	331	if (!target) {
	332	ret = -ESRCH;
	333	goto out;
	334	}
	335	} else
	336	target = current;
	337
	338	ret = 0;
	339
	340	/* having verified that the proposed changes are legal,
	341	we now put them into effect. */
	342	if (pid < 0) {
	343	if (pid == -1) /* all procs other than current and init */
	344	ret = cap_set_all(&effective, &inheritable, &permitted);
	345
	346	else /* all procs in process group */
	347	ret = cap_set_pg(-pid, &effective, &inheritable,
	348	&permitted);
	349	} else {
	350	ret = security_capset_check(target, &effective, &inheritable,
	351	&permitted);
	352	if (!ret)
	353	security_capset_set(target, &effective, &inheritable,
	354	&permitted);
	355	}
1da177e4 LT	356
1da177e4 LT	357	out:
314f70fd DW	358	read_unlock(&tasklist_lock);
314f70fd DW	359	spin_unlock(&task_capability_lock);
1da177e4	360
314f70fd	361	return ret;
1da177e4	362	}
12b5989b CW	363
	364	int __capable(struct task_struct *t, int cap)
	365	{
	366	if (security_capable(t, cap) == 0) {
	367	t->flags \|= PF_SUPERPRIV;
	368	return 1;
	369	}
	370	return 0;
	371	}
12b5989b CW	372
	373	int capable(int cap)
	374	{
	375	return __capable(current, cap);
	376	}
	377	EXPORT_SYMBOL(capable);