WebSVN – HelenOS – Diff – /trunk/kernel/generic/src/security/cap.c


/*
 * Copyright (c) 2006 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup generic
 * @{
 */
 
/**
 * @file    cap.c
 * @brief   Capabilities control.
 *
 * @see cap.h
 */
 
#include <security/cap.h>
#include <proc/task.h>
#include <synch/spinlock.h>
#include <syscall/sysarg64.h>
#include <syscall/copy.h>
#include <arch.h>
 
#include <errno.h>
 
/** Set capabilities.
 *
 * @param t Task whose capabilities are to be changed.
 * @param caps New set of capabilities.
 */
void cap_set(task_t *t, cap_t caps)
{
    ipl_t ipl;
   
    ipl = interrupts_disable();
    spinlock_lock(&t->lock);
   
    t->capabilities = caps;
   
    spinlock_unlock(&t->lock);
    interrupts_restore(ipl);
}
 
/** Get capabilities.
 *
 * @param t Task whose capabilities are to be returned.
 * @return Task's capabilities.
 */
cap_t cap_get(task_t *t)
{
    ipl_t ipl;
    cap_t caps;
   
    ipl = interrupts_disable();
    spinlock_lock(&t->lock);
   
    caps = t->capabilities;
   
    spinlock_unlock(&t->lock);
    interrupts_restore(ipl);
   
    return caps;
}
 
/** Grant capabilities to a task.
 *
 * The calling task must have the CAP_CAP capability.
 *
 * @param uspace_taskid_arg Userspace structure holding destination task ID.
 * @param caps Capabilities to grant.
 *
 * @return Zero on success or an error code from @ref errno.h.
 */
unative_t sys_cap_grant(sysarg64_t *uspace_taskid_arg, cap_t caps)
{
    sysarg64_t taskid_arg;
    task_t *t;
    ipl_t ipl;
    int rc;
   
    if (!(cap_get(TASK) & CAP_CAP))
        return (unative_t) EPERM;
   
    rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
    if (rc != 0)
        return (unative_t) rc;
       
    ipl = interrupts_disable();
    spinlock_lock(&tasks_lock);
    t = task_find_by_id((task_id_t) taskid_arg.value);
    if ((!t) || (!context_check(CONTEXT, t->context))) {
        spinlock_unlock(&tasks_lock);
        interrupts_restore(ipl);
        return (unative_t) ENOENT;
    }
   
    spinlock_lock(&t->lock);
    cap_set(t, cap_get(t) | caps);
    spinlock_unlock(&t->lock);
   
    spinlock_unlock(&tasks_lock);
    interrupts_restore(ipl);   
    return 0;
}
 
/** Revoke capabilities from a task.
 *
 * The calling task must have the CAP_CAP capability or the caller must
 * attempt to revoke capabilities from itself.
 *
 * @param uspace_taskid_arg Userspace structure holding destination task ID.
 * @param caps Capabilities to revoke.
 *
 * @return Zero on success or an error code from @ref errno.h.
 */
unative_t sys_cap_revoke(sysarg64_t *uspace_taskid_arg, cap_t caps)
{
    sysarg64_t taskid_arg;
    task_t *t;
    ipl_t ipl;
    int rc;
   
    rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
    if (rc != 0)
        return (unative_t) rc;
 
    ipl = interrupts_disable();
    spinlock_lock(&tasks_lock);
    t = task_find_by_id((task_id_t) taskid_arg.value);
    if ((!t) || (!context_check(CONTEXT, t->context))) {
        spinlock_unlock(&tasks_lock);
        interrupts_restore(ipl);
        return (unative_t) ENOENT;
    }
 
    /*
     * Revoking capabilities is different from granting them in that
     * a task can revoke capabilities from itself even if it
     * doesn't have CAP_CAP.
     */
    if (!(cap_get(TASK) & CAP_CAP) || !(t == TASK)) {
        spinlock_unlock(&tasks_lock);
        interrupts_restore(ipl);
        return (unative_t) EPERM;
    }
   
    spinlock_lock(&t->lock);
    cap_set(t, cap_get(t) & ~caps);
    spinlock_unlock(&t->lock);
 
    spinlock_unlock(&tasks_lock);
 
    interrupts_restore(ipl);
    return 0;
}
 
/** @}
 */
 
 

Rev 2071	Rev 2089
1	/*	1	/*
2	* Copyright (c) 2006 Jakub Jermar	2	* Copyright (c) 2006 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup generic	29	/** @addtogroup generic
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file cap.c	34	* @file cap.c
35	* @brief Capabilities control.	35	* @brief Capabilities control.
36	*	36	*
37	* @see cap.h	37	* @see cap.h
38	*/	38	*/
39		39
40	#include <security/cap.h>	40	#include <security/cap.h>
41	#include <proc/task.h>	41	#include <proc/task.h>
42	#include <synch/spinlock.h>	42	#include <synch/spinlock.h>
43	#include <syscall/sysarg64.h>	43	#include <syscall/sysarg64.h>
44	#include <syscall/copy.h>	44	#include <syscall/copy.h>
45	#include <arch.h>	45	#include <arch.h>
46	#include <typedefs.h>	-
47	#include <errno.h>	46	#include <errno.h>
48		47
49	/** Set capabilities.	48	/** Set capabilities.
50	*	49	*
51	* @param t Task whose capabilities are to be changed.	50	* @param t Task whose capabilities are to be changed.
52	* @param caps New set of capabilities.	51	* @param caps New set of capabilities.
53	*/	52	*/
54	void cap_set(task_t *t, cap_t caps)	53	void cap_set(task_t *t, cap_t caps)
55	{	54	{
56	ipl_t ipl;	55	ipl_t ipl;
57		56
58	ipl = interrupts_disable();	57	ipl = interrupts_disable();
59	spinlock_lock(&t->lock);	58	spinlock_lock(&t->lock);
60		59
61	t->capabilities = caps;	60	t->capabilities = caps;
62		61
63	spinlock_unlock(&t->lock);	62	spinlock_unlock(&t->lock);
64	interrupts_restore(ipl);	63	interrupts_restore(ipl);
65	}	64	}
66		65
67	/** Get capabilities.	66	/** Get capabilities.
68	*	67	*
69	* @param t Task whose capabilities are to be returned.	68	* @param t Task whose capabilities are to be returned.
70	* @return Task's capabilities.	69	* @return Task's capabilities.
71	*/	70	*/
72	cap_t cap_get(task_t *t)	71	cap_t cap_get(task_t *t)
73	{	72	{
74	ipl_t ipl;	73	ipl_t ipl;
75	cap_t caps;	74	cap_t caps;
76		75
77	ipl = interrupts_disable();	76	ipl = interrupts_disable();
78	spinlock_lock(&t->lock);	77	spinlock_lock(&t->lock);
79		78
80	caps = t->capabilities;	79	caps = t->capabilities;
81		80
82	spinlock_unlock(&t->lock);	81	spinlock_unlock(&t->lock);
83	interrupts_restore(ipl);	82	interrupts_restore(ipl);
84		83
85	return caps;	84	return caps;
86	}	85	}
87		86
88	/** Grant capabilities to a task.	87	/** Grant capabilities to a task.
89	*	88	*
90	* The calling task must have the CAP_CAP capability.	89	* The calling task must have the CAP_CAP capability.
91	*	90	*
92	* @param uspace_taskid_arg Userspace structure holding destination task ID.	91	* @param uspace_taskid_arg Userspace structure holding destination task ID.
93	* @param caps Capabilities to grant.	92	* @param caps Capabilities to grant.
94	*	93	*
95	* @return Zero on success or an error code from @ref errno.h.	94	* @return Zero on success or an error code from @ref errno.h.
96	*/	95	*/
97	unative_t sys_cap_grant(sysarg64_t *uspace_taskid_arg, cap_t caps)	96	unative_t sys_cap_grant(sysarg64_t *uspace_taskid_arg, cap_t caps)
98	{	97	{
99	sysarg64_t taskid_arg;	98	sysarg64_t taskid_arg;
100	task_t *t;	99	task_t *t;
101	ipl_t ipl;	100	ipl_t ipl;
102	int rc;	101	int rc;
103		102
104	if (!(cap_get(TASK) & CAP_CAP))	103	if (!(cap_get(TASK) & CAP_CAP))
105	return (unative_t) EPERM;	104	return (unative_t) EPERM;
106		105
107	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));	106	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
108	if (rc != 0)	107	if (rc != 0)
109	return (unative_t) rc;	108	return (unative_t) rc;
110		109
111	ipl = interrupts_disable();	110	ipl = interrupts_disable();
112	spinlock_lock(&tasks_lock);	111	spinlock_lock(&tasks_lock);
113	t = task_find_by_id((task_id_t) taskid_arg.value);	112	t = task_find_by_id((task_id_t) taskid_arg.value);
114	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {	113	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {
115	spinlock_unlock(&tasks_lock);	114	spinlock_unlock(&tasks_lock);
116	interrupts_restore(ipl);	115	interrupts_restore(ipl);
117	return (unative_t) ENOENT;	116	return (unative_t) ENOENT;
118	}	117	}
119		118
120	spinlock_lock(&t->lock);	119	spinlock_lock(&t->lock);
121	cap_set(t, cap_get(t) \| caps);	120	cap_set(t, cap_get(t) \| caps);
122	spinlock_unlock(&t->lock);	121	spinlock_unlock(&t->lock);
123		122
124	spinlock_unlock(&tasks_lock);	123	spinlock_unlock(&tasks_lock);
125	interrupts_restore(ipl);	124	interrupts_restore(ipl);
126	return 0;	125	return 0;
127	}	126	}
128		127
129	/** Revoke capabilities from a task.	128	/** Revoke capabilities from a task.
130	*	129	*
131	* The calling task must have the CAP_CAP capability or the caller must	130	* The calling task must have the CAP_CAP capability or the caller must
132	* attempt to revoke capabilities from itself.	131	* attempt to revoke capabilities from itself.
133	*	132	*
134	* @param uspace_taskid_arg Userspace structure holding destination task ID.	133	* @param uspace_taskid_arg Userspace structure holding destination task ID.
135	* @param caps Capabilities to revoke.	134	* @param caps Capabilities to revoke.
136	*	135	*
137	* @return Zero on success or an error code from @ref errno.h.	136	* @return Zero on success or an error code from @ref errno.h.
138	*/	137	*/
139	unative_t sys_cap_revoke(sysarg64_t *uspace_taskid_arg, cap_t caps)	138	unative_t sys_cap_revoke(sysarg64_t *uspace_taskid_arg, cap_t caps)
140	{	139	{
141	sysarg64_t taskid_arg;	140	sysarg64_t taskid_arg;
142	task_t *t;	141	task_t *t;
143	ipl_t ipl;	142	ipl_t ipl;
144	int rc;	143	int rc;
145		144
146	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));	145	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
147	if (rc != 0)	146	if (rc != 0)
148	return (unative_t) rc;	147	return (unative_t) rc;
149		148
150	ipl = interrupts_disable();	149	ipl = interrupts_disable();
151	spinlock_lock(&tasks_lock);	150	spinlock_lock(&tasks_lock);
152	t = task_find_by_id((task_id_t) taskid_arg.value);	151	t = task_find_by_id((task_id_t) taskid_arg.value);
153	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {	152	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {
154	spinlock_unlock(&tasks_lock);	153	spinlock_unlock(&tasks_lock);
155	interrupts_restore(ipl);	154	interrupts_restore(ipl);
156	return (unative_t) ENOENT;	155	return (unative_t) ENOENT;
157	}	156	}
158		157
159	/*	158	/*
160	* Revoking capabilities is different from granting them in that	159	* Revoking capabilities is different from granting them in that
161	* a task can revoke capabilities from itself even if it	160	* a task can revoke capabilities from itself even if it
162	* doesn't have CAP_CAP.	161	* doesn't have CAP_CAP.
163	*/	162	*/
164	if (!(cap_get(TASK) & CAP_CAP) \|\| !(t == TASK)) {	163	if (!(cap_get(TASK) & CAP_CAP) \|\| !(t == TASK)) {
165	spinlock_unlock(&tasks_lock);	164	spinlock_unlock(&tasks_lock);
166	interrupts_restore(ipl);	165	interrupts_restore(ipl);
167	return (unative_t) EPERM;	166	return (unative_t) EPERM;
168	}	167	}
169		168
170	spinlock_lock(&t->lock);	169	spinlock_lock(&t->lock);
171	cap_set(t, cap_get(t) & ~caps);	170	cap_set(t, cap_get(t) & ~caps);
172	spinlock_unlock(&t->lock);	171	spinlock_unlock(&t->lock);
173		172
174	spinlock_unlock(&tasks_lock);	173	spinlock_unlock(&tasks_lock);
175		174
176	interrupts_restore(ipl);	175	interrupts_restore(ipl);
177	return 0;	176	return 0;
178	}	177	}
179		178
180	/** @}	179	/** @}
181	*/	180	*/
182		181
183		182

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(root)/trunk/kernel/generic/src/security/cap.c – Rev 2071 → 2089