bsd/kern/kern_sfi.c

   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 #include <kern/policy_internal.h>
  45
  46 /*
  47  * This file provides the syscall-based configuration facility
  48  * for Selective Forced Idle (SFI). Input arguments have basic checking
  49  * applied here, although more specific semantic checking is done in
  50  * osfmk/kern/sfi.c. All copyin()/copyout() operations are performed
  51  * in this source file.
  52  */
  53
  54 #define SFI_DEBUG 0
  55
  56 #if SFI_DEBUG
  57 #define dprintf(...) printf(__VA_ARGS__)
  58 #else
  59 #define dprintf(...) do { } while(0)
  60 #endif
  61
  62 static int proc_apply_sfi_managed(proc_t p, void * arg);
  63
  64 int
  65 sfi_ctl(struct proc *p __unused, struct sfi_ctl_args *uap, int32_t *retval __unused)
  66 {
  67         uint32_t        operation = uap->operation;
  68         int                     error = 0;
  69         kern_return_t   kret = KERN_SUCCESS;
  70         uint64_t        out_time = 0;
  71
  72         switch (operation) {
  73         case SFI_CTL_OPERATION_SFI_SET_WINDOW:
  74                 if (uap->out_time != USER_ADDR_NULL) {
  75                         return EINVAL;
  76                 }
  77                 if (uap->sfi_class != SFI_CLASS_UNSPECIFIED) {
  78                         return EINVAL;
  79                 }
  80
  81                 error = priv_check_cred(kauth_cred_get(), PRIV_SELECTIVE_FORCED_IDLE, 0);
  82                 if (error) {
  83                         dprintf("%s failed privilege check for sfi_ctl: %d\n", p->p_comm, error);
  84                         return error;
  85                 } else {
  86                         dprintf("%s succeeded privilege check for sfi_ctl\n", p->p_comm);
  87                 }
  88
  89                 if (uap->time == 0) {
  90                         /* actually a cancel */
  91                         kret = sfi_window_cancel();
  92                 } else {
  93                         kret = sfi_set_window(uap->time);
  94                 }
  95
  96                 if (kret) {
  97                         error = EINVAL;
  98                 }
  99
 100                 break;
 101         case SFI_CTL_OPERATION_SFI_GET_WINDOW:
 102                 if (uap->time != 0) {
 103                         return EINVAL;
 104                 }
 105                 if (uap->sfi_class != SFI_CLASS_UNSPECIFIED) {
 106                         return EINVAL;
 107                 }
 108
 109                 kret = sfi_get_window(&out_time);
 110                 if (kret == KERN_SUCCESS) {
 111                         error = copyout(&out_time, uap->out_time, sizeof(out_time));
 112                 } else {
 113                         error = EINVAL;
 114                 }
 115
 116                 break;
 117         case SFI_CTL_OPERATION_SET_CLASS_OFFTIME:
 118                 if (uap->out_time != USER_ADDR_NULL) {
 119                         return EINVAL;
 120                 }
 121
 122                 error = priv_check_cred(kauth_cred_get(), PRIV_SELECTIVE_FORCED_IDLE, 0);
 123                 if (error) {
 124                         dprintf("%s failed privilege check for sfi_ctl: %d\n", p->p_comm, error);
 125                         return error;
 126                 } else {
 127                         dprintf("%s succeeded privilege check for sfi_ctl\n", p->p_comm);
 128                 }
 129
 130                 if (uap->time == 0) {
 131                         /* actually a cancel */
 132                         kret = sfi_class_offtime_cancel(uap->sfi_class);
 133                 } else {
 134                         kret = sfi_set_class_offtime(uap->sfi_class, uap->time);
 135                 }
 136
 137                 if (kret) {
 138                         error = EINVAL;
 139                 }
 140
 141                 break;
 142         case SFI_CTL_OPERATION_GET_CLASS_OFFTIME:
 143                 if (uap->time != 0) {
 144                         return EINVAL;
 145                 }
 146
 147                 kret = sfi_get_class_offtime(uap->sfi_class, &out_time);
 148                 if (kret == KERN_SUCCESS) {
 149                         error = copyout(&out_time, uap->out_time, sizeof(out_time));
 150                 } else {
 151                         error = EINVAL;
 152                 }
 153
 154                 break;
 155         default:
 156                 error = ENOTSUP;
 157                 break;
 158         }
 159
 160         return error;
 161 }
 162
 163 static int
 164 proc_apply_sfi_managed(proc_t p, void * arg)
 165 {
 166         uint32_t flags = *(uint32_t *)arg;
 167         pid_t pid = p->p_pid;
 168         boolean_t managed_enabled = (flags == SFI_PROCESS_SET_MANAGED)? TRUE : FALSE;
 169
 170         if (pid == 0) {         /* ignore setting on kernproc */
 171                 return PROC_RETURNED;
 172         }
 173
 174         if (managed_enabled) {
 175                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SFI, SFI_PID_SET_MANAGED) | DBG_FUNC_NONE, pid, 0, 0, 0, 0);
 176         } else {
 177                 KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SFI, SFI_PID_CLEAR_MANAGED) | DBG_FUNC_NONE, pid, 0, 0, 0, 0);
 178         }
 179
 180         proc_set_task_policy(p->task,
 181             TASK_POLICY_ATTRIBUTE, TASK_POLICY_SFI_MANAGED,
 182             managed_enabled ? TASK_POLICY_ENABLE : TASK_POLICY_DISABLE);
 183
 184         return PROC_RETURNED;
 185 }
 186
 187 int
 188 sfi_pidctl(struct proc *p __unused, struct sfi_pidctl_args *uap, int32_t *retval __unused)
 189 {
 190         uint32_t        operation = uap->operation;
 191         pid_t           pid = uap->pid;
 192         int                     error = 0;
 193         uint32_t        out_flags = 0;
 194         boolean_t       managed_enabled;
 195         proc_t          targetp;
 196
 197         switch (operation) {
 198         case SFI_PIDCTL_OPERATION_PID_SET_FLAGS:
 199                 if (uap->out_sfi_flags != USER_ADDR_NULL
 200                     || !(uap->sfi_flags & SFI_PROCESS_SET_MANAGED_MASK)
 201                     || uap->sfi_flags == SFI_PROCESS_SET_MANAGED_MASK) {
 202                         return EINVAL;
 203                 }
 204
 205                 error = priv_check_cred(kauth_cred_get(), PRIV_SELECTIVE_FORCED_IDLE, 0);
 206                 if (error) {
 207                         dprintf("%s failed privilege check for sfi_pidctl: %d\n", p->p_comm, error);
 208                         return error;
 209                 } else {
 210                         dprintf("%s succeeded privilege check for sfi_pidctl\n", p->p_comm);
 211                 }
 212
 213                 if (uap->pid == 0) {
 214                         /* only allow SFI_PROCESS_SET_UNMANAGED for pid 0 */
 215                         if (uap->sfi_flags != SFI_PROCESS_SET_UNMANAGED) {
 216                                 return EINVAL;
 217                         }
 218
 219                         proc_iterate(PROC_ALLPROCLIST, proc_apply_sfi_managed, (void *)&uap->sfi_flags, NULL, NULL);
 220                         break;
 221                 }
 222
 223                 targetp = proc_find(pid);
 224                 if (!targetp) {
 225                         error = ESRCH;
 226                         break;
 227                 }
 228
 229                 proc_apply_sfi_managed(targetp, (void *)&uap->sfi_flags);
 230
 231                 proc_rele(targetp);
 232
 233                 break;
 234         case SFI_PIDCTL_OPERATION_PID_GET_FLAGS:
 235                 if (uap->sfi_flags != 0) {
 236                         return EINVAL;
 237                 }
 238                 if (uap->pid == 0) {
 239                         return EINVAL;
 240                 }
 241
 242                 targetp = proc_find(pid);
 243                 if (!targetp) {
 244                         error = ESRCH;
 245                         break;
 246                 }
 247
 248                 managed_enabled = proc_get_task_policy(targetp->task, TASK_POLICY_ATTRIBUTE, TASK_POLICY_SFI_MANAGED);
 249
 250                 proc_rele(targetp);
 251
 252                 out_flags = managed_enabled ? SFI_PROCESS_SET_MANAGED : SFI_PROCESS_SET_UNMANAGED;
 253
 254                 error = copyout(&out_flags, uap->out_sfi_flags, sizeof(out_flags));
 255
 256                 break;
 257         default:
 258                 error = ENOTSUP;
 259                 break;
 260         }
 261
 262         return error;
 263 }