1/*
2 * Copyright (c) 2013 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 *
28 */
29
30#include <kern/assert.h>
31#include <kern/locks.h>
32#include <kern/task.h>
33#include <kern/thread.h>
34#include <kern/sfi.h>
35#include <libkern/libkern.h>
36#include <mach/mach_time.h>
37#include <pexpert/pexpert.h>
38#include <sys/proc.h>
39#include <sys/proc_info.h>
40#include <sys/sysproto.h>
41#include <sys/sfi.h>
42#include <sys/kdebug.h>
43#include <sys/priv.h>
44
45/*
46 * This file provides the syscall-based configuration facility
47 * for Selective Forced Idle (SFI). Input arguments have basic checking
48 * applied here, although more specific semantic checking is done in
49 * osfmk/kern/sfi.c. All copyin()/copyout() operations are performed
50 * in this source file.
51 */
52
53#define SFI_DEBUG 0
54
55#if SFI_DEBUG
56#define dprintf(...) printf(__VA_ARGS__)
57#else
58#define dprintf(...) do { } while(0)
59#endif
60
61static int proc_apply_sfi_managed(proc_t p, void * arg);
62
63int sfi_ctl(struct proc *p __unused, struct sfi_ctl_args *uap, int32_t *retval __unused)
64{
65	uint32_t	operation = uap->operation;
66	int			error = 0;
67	kern_return_t	kret = KERN_SUCCESS;
68	uint64_t	out_time = 0;
69
70	switch (operation) {
71		case SFI_CTL_OPERATION_SFI_SET_WINDOW:
72			if (uap->out_time != USER_ADDR_NULL) {
73				return EINVAL;
74			}
75			if (uap->sfi_class != SFI_CLASS_UNSPECIFIED) {
76				return EINVAL;
77			}
78
79			error = priv_check_cred(kauth_cred_get(), PRIV_SELECTIVE_FORCED_IDLE, 0);
80			if (error) {
81				dprintf("%s failed privilege check for sfi_ctl: %d\n", p->p_comm, error);
82				return (error);
83			} else {
84				dprintf("%s succeeded privilege check for sfi_ctl\n", p->p_comm);
85			}
86
87			if (uap->time == 0) {
88				/* actually a cancel */
89				kret = sfi_window_cancel();
90			} else {
91				kret = sfi_set_window(uap->time);
92			}
93
94			if (kret) {
95				error = EINVAL;
96			}
97
98			break;
99		case SFI_CTL_OPERATION_SFI_GET_WINDOW:
100			if (uap->time != 0) {
101				return EINVAL;
102			}
103			if (uap->sfi_class != SFI_CLASS_UNSPECIFIED) {
104				return EINVAL;
105			}
106
107			kret = sfi_get_window(&out_time);
108			if (kret == KERN_SUCCESS) {
109				error = copyout(&out_time, uap->out_time, sizeof(out_time));
110			} else {
111				error = EINVAL;
112			}
113
114			break;
115		case SFI_CTL_OPERATION_SET_CLASS_OFFTIME:
116			if (uap->out_time != USER_ADDR_NULL) {
117				return EINVAL;
118			}
119
120			error = priv_check_cred(kauth_cred_get(), PRIV_SELECTIVE_FORCED_IDLE, 0);
121			if (error) {
122				dprintf("%s failed privilege check for sfi_ctl: %d\n", p->p_comm, error);
123				return (error);
124			} else {
125				dprintf("%s succeeded privilege check for sfi_ctl\n", p->p_comm);
126			}
127
128			if (uap->time == 0) {
129				/* actually a cancel */
130				kret = sfi_class_offtime_cancel(uap->sfi_class);
131			} else {
132				kret = sfi_set_class_offtime(uap->sfi_class, uap->time);
133			}
134
135			if (kret) {
136				error = EINVAL;
137			}
138
139			break;
140		case SFI_CTL_OPERATION_GET_CLASS_OFFTIME:
141			if (uap->time != 0) {
142				return EINVAL;
143			}
144
145			kret = sfi_get_class_offtime(uap->sfi_class, &out_time);
146			if (kret == KERN_SUCCESS) {
147				error = copyout(&out_time, uap->out_time, sizeof(out_time));
148			} else {
149				error = EINVAL;
150			}
151
152			break;
153		default:
154			error = ENOTSUP;
155			break;
156	}
157
158	return error;
159}
160
161static int proc_apply_sfi_managed(proc_t p, void * arg)
162{
163	uint32_t flags = *(uint32_t *)arg;
164	pid_t pid = p->p_pid;
165	boolean_t managed_enabled = (flags == SFI_PROCESS_SET_MANAGED)? TRUE : FALSE;
166
167	if (pid == 0) {		/* ignore setting on kernproc */
168		return PROC_RETURNED;
169	}
170
171	if (managed_enabled) {
172		KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SFI, SFI_PID_SET_MANAGED) | DBG_FUNC_NONE, pid, 0, 0, 0, 0);
173	} else {
174		KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SFI, SFI_PID_CLEAR_MANAGED) | DBG_FUNC_NONE, pid, 0, 0, 0, 0);
175	}
176
177	proc_set_task_policy(p->task, THREAD_NULL,
178								 TASK_POLICY_ATTRIBUTE, TASK_POLICY_SFI_MANAGED,
179								 managed_enabled ? TASK_POLICY_ENABLE : TASK_POLICY_DISABLE);
180	return PROC_RETURNED;
181}
182
183int sfi_pidctl(struct proc *p __unused, struct sfi_pidctl_args *uap, int32_t *retval __unused)
184{
185	uint32_t	operation = uap->operation;
186	pid_t		pid = uap->pid;
187	int			error = 0;
188	uint32_t	out_flags = 0;
189	boolean_t	managed_enabled;
190	proc_t		targetp;
191
192	switch (operation) {
193		case SFI_PIDCTL_OPERATION_PID_SET_FLAGS:
194			if (uap->out_sfi_flags != USER_ADDR_NULL
195			    || !(uap->sfi_flags & SFI_PROCESS_SET_MANAGED_MASK)
196			    || uap->sfi_flags == SFI_PROCESS_SET_MANAGED_MASK) {
197				return EINVAL;
198			}
199
200			error = priv_check_cred(kauth_cred_get(), PRIV_SELECTIVE_FORCED_IDLE, 0);
201			if (error) {
202				dprintf("%s failed privilege check for sfi_pidctl: %d\n", p->p_comm, error);
203				return (error);
204			} else {
205				dprintf("%s succeeded privilege check for sfi_pidctl\n", p->p_comm);
206			}
207
208			if (uap->pid == 0) {
209				/* only allow SFI_PROCESS_SET_UNMANAGED for pid 0 */
210				if (uap->sfi_flags != SFI_PROCESS_SET_UNMANAGED) {
211					return EINVAL;
212				}
213
214				proc_iterate(PROC_ALLPROCLIST, proc_apply_sfi_managed, (void *)&uap->sfi_flags, NULL, NULL);
215				break;
216			}
217
218			targetp = proc_find(pid);
219			if (!targetp) {
220				error = ESRCH;
221				break;
222			}
223
224			proc_apply_sfi_managed(targetp, (void *)&uap->sfi_flags);
225
226			proc_rele(targetp);
227
228			break;
229		case SFI_PIDCTL_OPERATION_PID_GET_FLAGS:
230			if (uap->sfi_flags != 0) {
231				return EINVAL;
232			}
233			if (uap->pid == 0) {
234				return EINVAL;
235			}
236
237			targetp = proc_find(pid);
238			if (!targetp) {
239				error = ESRCH;
240				break;
241			}
242
243			managed_enabled = proc_get_task_policy(targetp->task, THREAD_NULL, TASK_POLICY_ATTRIBUTE, TASK_POLICY_SFI_MANAGED);
244
245			proc_rele(targetp);
246
247			out_flags = managed_enabled ? SFI_PROCESS_SET_MANAGED : SFI_PROCESS_SET_UNMANAGED;
248
249			error = copyout(&out_flags, uap->out_sfi_flags, sizeof(out_flags));
250
251			break;
252		default:
253			error = ENOTSUP;
254			break;
255	}
256
257	return error;
258}
259