1 // Copyright (c) 2023 Apple Inc. All rights reserved. 2 // 3 // @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 4 // 5 // This file contains Original Code and/or Modifications of Original Code 6 // as defined in and that are subject to the Apple Public Source License 7 // Version 2.0 (the 'License'). You may not use this file except in 8 // compliance with the License. The rights granted to you under the License 9 // may not be used to create, or enable the creation or redistribution of, 10 // unlawful or unlicensed copies of an Apple operating system, or to 11 // circumvent, violate, or enable the circumvention or violation of, any 12 // terms of an Apple operating system software license agreement. 13 // 14 // Please obtain a copy of the License at 15 // http://www.opensource.apple.com/apsl/ and read it before using this file. 16 // 17 // The Original Code and all software distributed under the License are 18 // distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 19 // EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 20 // INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 21 // FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 22 // Please see the License for the specific language governing rights and 23 // limitations under the License. 24 // 25 // @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 26 27 #include <kern/cpc.h> 28 #include <sys/sysctl.h> 29 30 SYSCTL_NODE(_kern, OID_AUTO, cpc, CTLFLAG_RD, 0, 31 "CPU Performance Counters subsystem"); 32 33 static int 34 _cpc_sysctl_secure SYSCTL_HANDLER_ARGS 35 { 36 int enforced = cpc_is_secure(); 37 int changed = 0; 38 int error = sysctl_io_number(req, enforced, sizeof(enforced), &enforced, 39 &changed); 40 if (error != 0) { 41 return error; 42 } 43 if (changed) { 44 #if CPC_INSECURE 45 cpc_change_security(enforced); 46 #else // CPC_INSECURE 47 return EPERM; 48 #endif // !CPC_INSECURE 49 } 50 return 0; 51 } 52 53 #if CPC_INSECURE 54 #define CPC_SYSCTL_SECURE_PROT CTLFLAG_RW 55 #else // CPC_INSECURE 56 #define CPC_SYSCTL_SECURE_PROT CTLFLAG_RD 57 #endif // !CPC_INSECURE 58 59 SYSCTL_PROC(_kern_cpc, OID_AUTO, secure, CPC_SYSCTL_SECURE_PROT | CTLTYPE_INT, 60 0, 0, _cpc_sysctl_secure, "I", 61 "Whether the CPU Performance Counters system is operating securely."); 62