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 <typedefs.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 1888	Rev 2071
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>	46	#include <typedefs.h>
47	#include <errno.h>	47	#include <errno.h>
48		48
49	/** Set capabilities.	49	/** Set capabilities.
50	*	50	*
51	* @param t Task whose capabilities are to be changed.	51	* @param t Task whose capabilities are to be changed.
52	* @param caps New set of capabilities.	52	* @param caps New set of capabilities.
53	*/	53	*/
54	void cap_set(task_t *t, cap_t caps)	54	void cap_set(task_t *t, cap_t caps)
55	{	55	{
56	ipl_t ipl;	56	ipl_t ipl;
57		57
58	ipl = interrupts_disable();	58	ipl = interrupts_disable();
59	spinlock_lock(&t->lock);	59	spinlock_lock(&t->lock);
60		60
61	t->capabilities = caps;	61	t->capabilities = caps;
62		62
63	spinlock_unlock(&t->lock);	63	spinlock_unlock(&t->lock);
64	interrupts_restore(ipl);	64	interrupts_restore(ipl);
65	}	65	}
66		66
67	/** Get capabilities.	67	/** Get capabilities.
68	*	68	*
69	* @param t Task whose capabilities are to be returned.	69	* @param t Task whose capabilities are to be returned.
70	* @return Task's capabilities.	70	* @return Task's capabilities.
71	*/	71	*/
72	cap_t cap_get(task_t *t)	72	cap_t cap_get(task_t *t)
73	{	73	{
74	ipl_t ipl;	74	ipl_t ipl;
75	cap_t caps;	75	cap_t caps;
76		76
77	ipl = interrupts_disable();	77	ipl = interrupts_disable();
78	spinlock_lock(&t->lock);	78	spinlock_lock(&t->lock);
79		79
80	caps = t->capabilities;	80	caps = t->capabilities;
81		81
82	spinlock_unlock(&t->lock);	82	spinlock_unlock(&t->lock);
83	interrupts_restore(ipl);	83	interrupts_restore(ipl);
84		84
85	return caps;	85	return caps;
86	}	86	}
87		87
88	/** Grant capabilities to a task.	88	/** Grant capabilities to a task.
89	*	89	*
90	* The calling task must have the CAP_CAP capability.	90	* The calling task must have the CAP_CAP capability.
91	*	91	*
92	* @param uspace_taskid_arg Userspace structure holding destination task ID.	92	* @param uspace_taskid_arg Userspace structure holding destination task ID.
93	* @param caps Capabilities to grant.	93	* @param caps Capabilities to grant.
94	*	94	*
95	* @return Zero on success or an error code from @ref errno.h.	95	* @return Zero on success or an error code from @ref errno.h.
96	*/	96	*/
97	unative_t sys_cap_grant(sysarg64_t *uspace_taskid_arg, cap_t caps)	97	unative_t sys_cap_grant(sysarg64_t *uspace_taskid_arg, cap_t caps)
98	{	98	{
99	sysarg64_t taskid_arg;	99	sysarg64_t taskid_arg;
100	task_t *t;	100	task_t *t;
101	ipl_t ipl;	101	ipl_t ipl;
102	int rc;	102	int rc;
103		103
104	if (!(cap_get(TASK) & CAP_CAP))	104	if (!(cap_get(TASK) & CAP_CAP))
105	return (unative_t) EPERM;	105	return (unative_t) EPERM;
106		106
107	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));	107	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
108	if (rc != 0)	108	if (rc != 0)
109	return (unative_t) rc;	109	return (unative_t) rc;
110		110
111	ipl = interrupts_disable();	111	ipl = interrupts_disable();
112	spinlock_lock(&tasks_lock);	112	spinlock_lock(&tasks_lock);
113	t = task_find_by_id((task_id_t) taskid_arg.value);	113	t = task_find_by_id((task_id_t) taskid_arg.value);
114	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {	114	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {
115	spinlock_unlock(&tasks_lock);	115	spinlock_unlock(&tasks_lock);
116	interrupts_restore(ipl);	116	interrupts_restore(ipl);
117	return (unative_t) ENOENT;	117	return (unative_t) ENOENT;
118	}	118	}
119		119
120	spinlock_lock(&t->lock);	120	spinlock_lock(&t->lock);
121	cap_set(t, cap_get(t) \| caps);	121	cap_set(t, cap_get(t) \| caps);
122	spinlock_unlock(&t->lock);	122	spinlock_unlock(&t->lock);
123		123
124	spinlock_unlock(&tasks_lock);	124	spinlock_unlock(&tasks_lock);
125	interrupts_restore(ipl);	125	interrupts_restore(ipl);
126	return 0;	126	return 0;
127	}	127	}
128		128
129	/** Revoke capabilities from a task.	129	/** Revoke capabilities from a task.
130	*	130	*
131	* The calling task must have the CAP_CAP capability or the caller must	131	* The calling task must have the CAP_CAP capability or the caller must
132	* attempt to revoke capabilities from itself.	132	* attempt to revoke capabilities from itself.
133	*	133	*
134	* @param uspace_taskid_arg Userspace structure holding destination task ID.	134	* @param uspace_taskid_arg Userspace structure holding destination task ID.
135	* @param caps Capabilities to revoke.	135	* @param caps Capabilities to revoke.
136	*	136	*
137	* @return Zero on success or an error code from @ref errno.h.	137	* @return Zero on success or an error code from @ref errno.h.
138	*/	138	*/
139	unative_t sys_cap_revoke(sysarg64_t *uspace_taskid_arg, cap_t caps)	139	unative_t sys_cap_revoke(sysarg64_t *uspace_taskid_arg, cap_t caps)
140	{	140	{
141	sysarg64_t taskid_arg;	141	sysarg64_t taskid_arg;
142	task_t *t;	142	task_t *t;
143	ipl_t ipl;	143	ipl_t ipl;
144	int rc;	144	int rc;
145		145
146	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));	146	rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
147	if (rc != 0)	147	if (rc != 0)
148	return (unative_t) rc;	148	return (unative_t) rc;
149		149
150	ipl = interrupts_disable();	150	ipl = interrupts_disable();
151	spinlock_lock(&tasks_lock);	151	spinlock_lock(&tasks_lock);
152	t = task_find_by_id((task_id_t) taskid_arg.value);	152	t = task_find_by_id((task_id_t) taskid_arg.value);
153	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {	153	if ((!t) \|\| (!context_check(CONTEXT, t->context))) {
154	spinlock_unlock(&tasks_lock);	154	spinlock_unlock(&tasks_lock);
155	interrupts_restore(ipl);	155	interrupts_restore(ipl);
156	return (unative_t) ENOENT;	156	return (unative_t) ENOENT;
157	}	157	}
158		158
159	/*	159	/*
160	* Revoking capabilities is different from granting them in that	160	* Revoking capabilities is different from granting them in that
161	* a task can revoke capabilities from itself even if it	161	* a task can revoke capabilities from itself even if it
162	* doesn't have CAP_CAP.	162	* doesn't have CAP_CAP.
163	*/	163	*/
164	if (!(cap_get(TASK) & CAP_CAP) \|\| !(t == TASK)) {	164	if (!(cap_get(TASK) & CAP_CAP) \|\| !(t == TASK)) {
165	spinlock_unlock(&tasks_lock);	165	spinlock_unlock(&tasks_lock);
166	interrupts_restore(ipl);	166	interrupts_restore(ipl);
167	return (unative_t) EPERM;	167	return (unative_t) EPERM;
168	}	168	}
169		169
170	spinlock_lock(&t->lock);	170	spinlock_lock(&t->lock);
171	cap_set(t, cap_get(t) & ~caps);	171	cap_set(t, cap_get(t) & ~caps);
172	spinlock_unlock(&t->lock);	172	spinlock_unlock(&t->lock);
173		173
174	spinlock_unlock(&tasks_lock);	174	spinlock_unlock(&tasks_lock);
175		175
176	interrupts_restore(ipl);	176	interrupts_restore(ipl);
177	return 0;	177	return 0;
178	}	178	}
179		179
180	/** @}	180	/** @}
181	*/	181	*/
182		182
183		183

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(root)/trunk/kernel/generic/src/security/cap.c – Rev 1888 → 2071