libSystemConfiguration/libSystemConfiguration_server.c

   1 /*
   2  * Copyright (c) 2012-2018 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 #include <os/availability.h>
  25 #include <TargetConditionals.h>
  26 #include <dispatch/dispatch.h>
  27 #include <vproc.h>
  28 #include <vproc_priv.h>
  29 #include <xpc/xpc.h>
  30 #include <xpc/private.h>
  31
  32 #include <CoreFoundation/CoreFoundation.h>
  33 #include <SystemConfiguration/SCPrivate.h>
  34 #include "libSystemConfiguration_server.h"
  35
  36 #define kTrailingEdgeAgentEntitlement "com.apple.SystemConfiguration.trailing-edge-agent"
  37
  38 #ifdef  SC_LOG_HANDLE
  39 #include <os/log.h>
  40 os_log_t        SC_LOG_HANDLE;
  41 #endif  //SC_LOG_HANDLE
  42
  43
  44 #pragma mark -
  45 #pragma mark client connection trackng
  46
  47
  48 typedef struct {
  49         xpc_connection_t        connection;
  50 } client_key_t;
  51
  52 typedef struct {
  53         pid_t                   pid;
  54         uint64_t                generation_pushed;
  55         uint64_t                generation_acknowledged;
  56 } client_val_t;
  57
  58
  59 static __inline__ CF_RETURNS_RETAINED CFDataRef
  60 _client_key(xpc_connection_t c)
  61 {
  62         client_key_t    key;
  63         CFDataRef       client_key;
  64
  65         key.connection = c;
  66         client_key = CFDataCreate(NULL, (UInt8 *)&key, sizeof(key));
  67         return client_key;
  68 }
  69
  70
  71 static void
  72 _handle_entitlement_check_failure(pid_t pid)
  73 {
  74         static Boolean                  cleanupScheduled        = FALSE;
  75         static dispatch_once_t          initializer             = 0;
  76         static CFMutableArrayRef        pids                    = NULL;
  77         static dispatch_queue_t         queue                   = NULL;
  78
  79         dispatch_once(&initializer, ^{
  80                 pids = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
  81                 queue = dispatch_queue_create("handle unentitled ack", NULL);
  82         });
  83
  84         dispatch_sync(queue, ^{
  85                 CFNumberRef     pidNumber       = CFNumberCreate(kCFAllocatorDefault, kCFNumberIntType, &pid);
  86
  87                 if (!CFArrayContainsValue(pids, CFRangeMake(0, CFArrayGetCount(pids)), pidNumber)) {
  88                         CFArrayAppendValue(pids, pidNumber);
  89
  90                         SC_log(LOG_INFO, "DNS/nwi dropping ack w/no entitlement, pid = %d", pid);
  91
  92                         if (!cleanupScheduled) {
  93                                 cleanupScheduled = TRUE;
  94                                 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 180LL * NSEC_PER_SEC), queue, ^{
  95                                         CFArrayRemoveAllValues(pids);
  96                                         cleanupScheduled = FALSE;
  97                                 });
  98                         }
  99                 }
 100
 101                 CFRelease(pidNumber);
 102         });
 103 }
 104
 105
 106 /*
 107  * libSystemConfiguraiton_client
 108  *
 109  * - all APIs must be called from the same [serial] dispatch queue
 110  */
 111
 112
 113 __private_extern__
 114 void
 115 _libSC_info_server_init(libSC_info_server_t *server_info) {
 116         bzero(server_info, sizeof(*server_info));
 117         server_info->info = CFDictionaryCreateMutable(NULL,
 118                                                       0,
 119                                                       &kCFTypeDictionaryKeyCallBacks,
 120                                                       &kCFTypeDictionaryValueCallBacks);
 121         return;
 122 }
 123
 124
 125 __private_extern__
 126 void
 127 _libSC_info_server_set_data(libSC_info_server_t *server_info,
 128                             CFDataRef           data,
 129                             uint64_t            generation)
 130 {
 131         // update stored configuration
 132         if (server_info->data != NULL) {
 133                 CFRelease(server_info->data);
 134                 server_info->data = NULL;
 135         }
 136         if (data != NULL) {
 137                 CFRetain(data);
 138                 server_info->data = data;
 139         }
 140
 141         // update generation
 142         if (generation == 0) {
 143                 // generation must be non-zero
 144                 generation = 1;
 145         }
 146         server_info->generation = generation;
 147
 148         // new configuration, all ack'ing clients need to
 149         // check-in again
 150         server_info->inSync_NO += server_info->inSync_YES;
 151         server_info->inSync_YES = 0;
 152
 153         return;
 154 }
 155
 156
 157 /*
 158  * _libSC_info_server_in_sync
 159  *
 160  * Called to check if all of the "active" configuration [XPC] connection
 161  * are in sync with the requested generation.
 162  */
 163 __private_extern__
 164 Boolean
 165 _libSC_info_server_in_sync(libSC_info_server_t *server_info)
 166 {
 167         return (server_info->inSync_NO == 0) ? TRUE : FALSE;
 168 }
 169
 170
 171 /*
 172  * _libSC_info_server_open
 173  *
 174  * Called when a new configuration [XPC] connection
 175  * is established.
 176  *
 177  * - tracks the last generation pushed to the caller and
 178  *   the last generation ack'd by the caller
 179  */
 180 __private_extern__
 181 void
 182 _libSC_info_server_open(libSC_info_server_t     *server_info,
 183                         xpc_connection_t        c)
 184 {
 185         CFDataRef               client_key;
 186         CFMutableDataRef        client_val;
 187         client_val_t            *val;
 188
 189         client_key = _client_key(c);
 190
 191         client_val = CFDataCreateMutable(NULL, sizeof(*val));
 192         CFDataSetLength(client_val, sizeof(*val));
 193
 194         val = (client_val_t *)(void *)CFDataGetMutableBytePtr(client_val);
 195         val->pid                     = xpc_connection_get_pid(c);
 196         val->generation_pushed       = 0;
 197         val->generation_acknowledged = 0;
 198
 199         CFDictionarySetValue(server_info->info, client_key, client_val);
 200         CFRelease(client_key);
 201         CFRelease(client_val);
 202
 203         return;
 204 }
 205
 206
 207 /*
 208  * _libSC_info_server_get_data
 209  *
 210  * Called when a [XPC] connection wants the current configuration.
 211  *
 212  * - updates the last generation pushed to the caller
 213  */
 214 __private_extern__
 215 CFDataRef
 216 _libSC_info_server_get_data(libSC_info_server_t *server_info,
 217                             xpc_connection_t    c,
 218                             uint64_t            *generation)
 219 {
 220         CFDataRef               client_key;
 221         CFMutableDataRef        client_val;
 222         client_val_t            *val;
 223
 224         // update last generation pushed to client
 225         client_key = _client_key(c);
 226         client_val = (CFMutableDataRef)CFDictionaryGetValue(server_info->info, client_key);
 227         CFRelease(client_key);
 228
 229         val = (client_val_t *)(void *)CFDataGetMutableBytePtr(client_val);
 230         val->generation_pushed = server_info->generation;
 231
 232         // return generation
 233         *generation = server_info->generation;
 234         if (*generation == 1) {
 235                 *generation = 0;
 236         }
 237
 238         // return data
 239         return server_info->data;
 240 }
 241
 242
 243 /*
 244  * _libSC_info_server_acknowledged
 245  *
 246  * Called when a [XPC] connection wants to acknowledge a
 247  * processed configuration.
 248  *
 249  * - updates the last generation ack'd by the caller
 250  * - updates the count of [XPC] connections that are / not in sync
 251  */
 252 __private_extern__
 253 Boolean
 254 _libSC_info_server_acknowledged(libSC_info_server_t     *server_info,
 255                                 xpc_connection_t        c,
 256                                 uint64_t                generation)
 257 {
 258         CFDataRef               client_key;
 259         CFMutableDataRef        client_val;
 260         xpc_object_t            ent_value;
 261         Boolean                 entitled        = FALSE;
 262         Boolean                 sync_updated    = FALSE;
 263         client_val_t            *val;
 264
 265         ent_value = xpc_connection_copy_entitlement_value(c, kTrailingEdgeAgentEntitlement);
 266         if (ent_value != NULL) {
 267                 if (xpc_get_type(ent_value) == XPC_TYPE_BOOL) {
 268                         entitled = xpc_bool_get_value(ent_value);
 269                 }
 270                 xpc_release(ent_value);
 271         }
 272
 273         if (!entitled) {
 274                 _handle_entitlement_check_failure(xpc_connection_get_pid(c));
 275                 return FALSE;
 276         }
 277
 278         client_key = _client_key(c);
 279         client_val = (CFMutableDataRef)CFDictionaryGetValue(server_info->info, client_key);
 280         CFRelease(client_key);
 281
 282         val = (client_val_t *)(void *)CFDataGetMutableBytePtr(client_val);
 283
 284         if (val->generation_acknowledged == 0) {
 285                 // if first ack
 286                 if (generation == server_info->generation) {
 287                         server_info->inSync_YES++;
 288                 } else {
 289                         server_info->inSync_NO++;
 290                         sync_updated = TRUE;
 291                 }
 292         } else if ((generation != val->generation_acknowledged) &&
 293                     (generation == server_info->generation)) {
 294                 // if we've previously ack'd a configuration
 295                 // ... and if we are ack'ing a configuration
 296                 //     that we have not previously ack'd
 297                 // ... and if we're ack'ing the current stored
 298                 //     configuration
 299                 server_info->inSync_NO--;
 300                 server_info->inSync_YES++;
 301                 sync_updated = TRUE;
 302         }
 303
 304         val->generation_acknowledged = generation;
 305
 306         return sync_updated;
 307 }
 308
 309
 310 /*
 311  * _libSC_info_server_close
 312  *
 313  * Called when a configuration [XPC] connection is closed.
 314  */
 315 __private_extern__
 316 Boolean
 317 _libSC_info_server_close(libSC_info_server_t    *server_info,
 318                          xpc_connection_t       c)
 319 {
 320         CFDataRef               client_key;
 321         CFMutableDataRef        client_val;
 322         Boolean                 sync_updated    = FALSE;
 323
 324         client_key = _client_key(c);
 325
 326         // get client info, remove ack'd info
 327         client_val = (CFMutableDataRef)CFDictionaryGetValue(server_info->info, client_key);
 328         if (client_val != NULL) {
 329                 client_val_t    *val;
 330
 331                 val = (client_val_t *)(void *)CFDataGetMutableBytePtr(client_val);
 332                 if (val->generation_acknowledged > 0) {
 333                         // if we've previously ack'd a configuration
 334                         if (val->generation_acknowledged == server_info->generation) {
 335                                 // if currently in sync
 336                                 server_info->inSync_YES--;
 337                         } else {
 338                                 // if currently NOT in sync
 339                                 server_info->inSync_NO--;
 340                                 sync_updated = TRUE;
 341                         }
 342                 }
 343         }
 344
 345         CFDictionaryRemoveValue(server_info->info, client_key);
 346         CFRelease(client_key);
 347
 348         return sync_updated;
 349 }
 350