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