Plugins/KernelEventMonitor/ev_extra.m

   1 /*
   2  * Copyright (c) 2013, 2014 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*
  25  * Modification History
  26  *
  27  * October 7, 2013      Allan Nathanson <ajn@apple.com>
  28  * - initial revision
  29  */
  30
  31
  32 #include <CoreFoundation/CoreFoundation.h>
  33 #include <SystemConfiguration/SystemConfiguration.h>
  34 #include <SystemConfiguration/SCPrivate.h>
  35
  36 #include "eventmon.h"
  37 #include "ev_extra.h"
  38
  39
  40 static CFBooleanRef
  41 is_expensive(SCNetworkInterfaceRef interface)
  42 {
  43         CFBooleanRef    expensive       = NULL;
  44         CFStringRef     interfaceType;
  45
  46         while (interface != NULL) {
  47                 SCNetworkInterfaceRef   child;
  48
  49                 child = SCNetworkInterfaceGetInterface(interface);
  50                 if (child == NULL) {
  51                         break;
  52                 }
  53
  54                 interface = child;
  55         }
  56
  57         // assume NOT expensive
  58         expensive = kCFBooleanFalse;
  59
  60         interfaceType = SCNetworkInterfaceGetInterfaceType(interface);
  61         if (_SCNetworkInterfaceIsTethered(interface)) {
  62                 // if tethered (to iOS) interface
  63                 expensive = kCFBooleanTrue;
  64         } else if (_SCNetworkInterfaceIsBluetoothPAN(interface)) {
  65                 // if BT-PAN interface
  66                 expensive = kCFBooleanTrue;
  67         } else if (CFEqual(interfaceType, kSCNetworkInterfaceTypeWWAN)) {
  68                 // if WWAN [Ethernet] interface
  69                 expensive = kCFBooleanTrue;
  70         }
  71
  72         return expensive;
  73 }
  74
  75
  76 static int
  77 ifexpensive_set(int s, const char * name, uint32_t expensive)
  78 {
  79 #if     defined(SIOCSIFEXPENSIVE) && !defined(MAIN)
  80         struct ifreq    ifr;
  81
  82         bzero(&ifr, sizeof(ifr));
  83         strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
  84         ifr.ifr_expensive = expensive;
  85         return (ioctl(s, SIOCSIFEXPENSIVE, &ifr));
  86 #else   // defined(SIOCSIFEXPENSIVE) && !defined(MAIN)
  87         return 0;
  88 #endif  // defined(SIOCSIFEXPENSIVE) && !defined(MAIN)
  89 }
  90
  91
  92 __private_extern__
  93 CFBooleanRef
  94 interface_update_expensive(const char *if_name)
  95 {
  96         CFBooleanRef            expensive       = NULL;
  97         SCNetworkInterfaceRef   interface;
  98         CFStringRef             interface_name;
  99         int                     s;
 100
 101         interface_name = CFStringCreateWithCString(NULL, if_name, kCFStringEncodingMacRoman);
 102         interface = _SCNetworkInterfaceCreateWithBSDName(NULL, interface_name, kIncludeNoVirtualInterfaces);
 103         CFRelease(interface_name);
 104
 105         if (interface != NULL) {
 106                 expensive = is_expensive(interface);
 107                 CFRelease(interface);
 108         }
 109
 110         // mark ... or clear ... the [if_name] interface as "expensive"
 111         s = dgram_socket(AF_INET);
 112         if (s != -1) {
 113                 ifexpensive_set(s,
 114                                 if_name,
 115                                 ((expensive != NULL) && CFBooleanGetValue(expensive)) ? 1 : 0);
 116                 close(s);
 117         }
 118
 119         return expensive;
 120 }
 121
 122
 123 #ifdef  MAIN
 124
 125 int
 126 dgram_socket(int domain)
 127 {
 128         return (socket(domain, SOCK_DGRAM, 0));
 129 }
 130
 131 int
 132 main(int argc, char **argv)
 133 {
 134         CFBooleanRef    expensive;
 135
 136         if (argc < 1 + 1) {
 137                 SCPrint(TRUE, stderr, CFSTR("usage: %s <interface>\n"), argv[0]);
 138                 exit(1);
 139         }
 140
 141         expensive = interface_update_expensive(argv[1]);
 142         if (expensive != NULL) {
 143                 SCPrint(TRUE, stdout, CFSTR("interface \"%s\": %@\n"), argv[1], expensive);
 144         } else {
 145                 SCPrint(TRUE, stdout, CFSTR("interface \"%s\": could not determine \"expensive\" status\n"), argv[1]);
 146         }
 147
 148         exit(0);
 149 }
 150 #endif  // MAIN