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
  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
  61 static int proc_apply_sfi_managed(proc_t p, void * arg);
  62
  63 int 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
 161 static 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
 183 int 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 }