configd.tproj/configd_server.c

   1 /*
   2  * Copyright (c) 2000-2007 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  * March 9, 2004                Allan Nathanson <ajn@apple.com>
  28  * - add DNS configuration server
  29  *
  30  * June 1, 2001                 Allan Nathanson <ajn@apple.com>
  31  * - public API conversion
  32  *
  33  * March 24, 2000               Allan Nathanson <ajn@apple.com>
  34  * - initial revision
  35  */
  36
  37 #include <sysexits.h>
  38 #include <unistd.h>
  39 #include <sys/types.h>
  40 #include <servers/bootstrap.h>
  41
  42 #include "configd.h"
  43 #include "configd_server.h"
  44 #include "notify_server.h"
  45 #include "session.h"
  46
  47 /* MiG generated externals and functions */
  48 extern struct mig_subsystem     _config_subsystem;
  49 extern boolean_t                config_server(mach_msg_header_t *, mach_msg_header_t *);
  50
  51 #include "shared_dns_info_types.h"
  52 #include "dnsinfo_server.h"
  53
  54 /* MiG generated externals and functions */
  55 extern struct mig_subsystem     _shared_dns_info_subsystem;
  56 extern boolean_t                shared_dns_info_server(mach_msg_header_t *, mach_msg_header_t *);
  57
  58 /* configd server port (for new session requests) */
  59 static CFMachPortRef            configd_port            = NULL;
  60
  61 /* priviledged bootstrap port (for registering/unregistering w/launchd) */
  62 static mach_port_t              priv_bootstrap_port     = MACH_PORT_NULL;
  63
  64 __private_extern__
  65 boolean_t
  66 config_demux(mach_msg_header_t *request, mach_msg_header_t *reply)
  67 {
  68         Boolean                         processed = FALSE;
  69
  70         /*
  71          * (attempt to) process SCDynamicStore requests.
  72          */
  73         processed = config_server(request, reply);
  74         if (processed) {
  75                 return TRUE;
  76         }
  77
  78         /*
  79          * (attempt to) process DNS configuration requests.
  80          */
  81         processed = shared_dns_info_server(request, reply);
  82         if (processed) {
  83                 return TRUE;
  84         }
  85
  86         /*
  87          * (attempt to) process (NO MORE SENDERS) notification messages.
  88          */
  89         processed = notify_server(request, reply);
  90         if (processed) {
  91                 return TRUE;
  92         }
  93
  94         /*
  95          * unknown message ID, log and return an error.
  96          */
  97         SCLog(TRUE, LOG_ERR, CFSTR("config_demux(): unknown message ID (%d) received"), request->msgh_id);
  98         reply->msgh_bits        = MACH_MSGH_BITS(MACH_MSGH_BITS_REMOTE(request->msgh_bits), 0);
  99         reply->msgh_remote_port = request->msgh_remote_port;
 100         reply->msgh_size        = sizeof(mig_reply_error_t);    /* Minimal size */
 101         reply->msgh_local_port  = MACH_PORT_NULL;
 102         reply->msgh_id          = request->msgh_id + 100;
 103         ((mig_reply_error_t *)reply)->NDR = NDR_record;
 104         ((mig_reply_error_t *)reply)->RetCode = MIG_BAD_ID;
 105
 106         return FALSE;
 107 }
 108
 109
 110 #define MACH_MSG_BUFFER_SIZE    128
 111
 112
 113 __private_extern__
 114 void
 115 configdCallback(CFMachPortRef port, void *msg, CFIndex size, void *info)
 116 {
 117         mig_reply_error_t *     bufRequest      = msg;
 118         uint32_t                bufReply_q[MACH_MSG_BUFFER_SIZE/sizeof(uint32_t)];
 119         mig_reply_error_t *     bufReply        = (mig_reply_error_t *)bufReply_q;
 120         static CFIndex          bufSize         = 0;
 121         mach_msg_return_t       mr;
 122         int                     options;
 123
 124         if (bufSize == 0) {
 125                 // get max size for MiG reply buffers
 126                 bufSize = _config_subsystem.maxsize;
 127                 if (_shared_dns_info_subsystem.maxsize > bufSize) {
 128                         bufSize = _shared_dns_info_subsystem.maxsize;
 129                 }
 130
 131                 // check if our on-the-stack reply buffer will be big enough
 132                 if (bufSize > sizeof(bufReply_q)) {
 133                         SCLog(TRUE, LOG_NOTICE,
 134                               CFSTR("configdCallback(): buffer size should be increased > %d"),
 135                               _config_subsystem.maxsize);
 136                 }
 137         }
 138
 139         if (bufSize > sizeof(bufReply_q)) {
 140                 bufReply = CFAllocatorAllocate(NULL, _config_subsystem.maxsize, 0);
 141         }
 142
 143         /* we have a request message */
 144         (void) config_demux(&bufRequest->Head, &bufReply->Head);
 145
 146         if (!(bufReply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)) {
 147                 if (bufReply->RetCode == MIG_NO_REPLY) {
 148                         bufReply->Head.msgh_remote_port = MACH_PORT_NULL;
 149                 } else if ((bufReply->RetCode != KERN_SUCCESS) &&
 150                            (bufRequest->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)) {
 151                         /*
 152                          * destroy the request - but not the reply port
 153                          */
 154                         bufRequest->Head.msgh_remote_port = MACH_PORT_NULL;
 155                         mach_msg_destroy(&bufRequest->Head);
 156                 }
 157         }
 158
 159         if (bufReply->Head.msgh_remote_port != MACH_PORT_NULL) {
 160                 /*
 161                  * send reply.
 162                  *
 163                  * We don't want to block indefinitely because the client
 164                  * isn't receiving messages from the reply port.
 165                  * If we have a send-once right for the reply port, then
 166                  * this isn't a concern because the send won't block.
 167                  * If we have a send right, we need to use MACH_SEND_TIMEOUT.
 168                  * To avoid falling off the kernel's fast RPC path unnecessarily,
 169                  * we only supply MACH_SEND_TIMEOUT when absolutely necessary.
 170                  */
 171
 172                 options = MACH_SEND_MSG;
 173                 if (MACH_MSGH_BITS_REMOTE(bufReply->Head.msgh_bits) != MACH_MSG_TYPE_MOVE_SEND_ONCE) {
 174                         options |= MACH_SEND_TIMEOUT;
 175                 }
 176                 mr = mach_msg(&bufReply->Head,          /* msg */
 177                               options,                  /* option */
 178                               bufReply->Head.msgh_size, /* send_size */
 179                               0,                        /* rcv_size */
 180                               MACH_PORT_NULL,           /* rcv_name */
 181                               MACH_MSG_TIMEOUT_NONE,    /* timeout */
 182                               MACH_PORT_NULL);          /* notify */
 183
 184                 /* Has a message error occurred? */
 185                 switch (mr) {
 186                         case MACH_SEND_INVALID_DEST:
 187                         case MACH_SEND_TIMED_OUT:
 188                                 break;
 189                         default :
 190                                 /* Includes success case.  */
 191                                 goto done;
 192                 }
 193         }
 194
 195         if (bufReply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX) {
 196                 mach_msg_destroy(&bufReply->Head);
 197         }
 198
 199     done :
 200
 201         if (bufReply != (mig_reply_error_t *)bufReply_q)
 202                 CFAllocatorDeallocate(NULL, bufReply);
 203         return;
 204 }
 205
 206
 207 __private_extern__
 208 boolean_t
 209 server_active(mach_port_t *restart_service_port)
 210 {
 211         char                    *service_name;
 212         kern_return_t           status;
 213
 214         service_name = getenv("SCD_SERVER");
 215         if (!service_name) {
 216                 service_name = SCD_SERVER;
 217         }
 218
 219         /* Check "configd" server status */
 220         status = bootstrap_check_in(bootstrap_port, service_name, restart_service_port);
 221         switch (status) {
 222                 case BOOTSTRAP_SUCCESS :
 223                         /* if we are being restarted by launchd */
 224                         priv_bootstrap_port = bootstrap_port;
 225                         break;
 226                 case BOOTSTRAP_SERVICE_ACTIVE :
 227                 case BOOTSTRAP_NOT_PRIVILEGED :
 228                         /* if another instance of the server is active (or starting) */
 229                         fprintf(stderr, "'%s' server already active\n",
 230                                 service_name);
 231                         return TRUE;
 232                 case BOOTSTRAP_UNKNOWN_SERVICE :
 233                         /* if the server is not currently registered/active */
 234                         *restart_service_port = MACH_PORT_NULL;
 235                         break;
 236                 default :
 237                         fprintf(stderr,
 238                                 "bootstrap_check_in() failed: %s\n",
 239                                 bootstrap_strerror(status));
 240                         exit (EX_UNAVAILABLE);
 241         }
 242
 243         return FALSE;
 244 }
 245
 246
 247 static CFStringRef
 248 serverMPCopyDescription(const void *info)
 249 {
 250         return CFStringCreateWithFormat(NULL, NULL, CFSTR("<main DynamicStore MP>"));
 251 }
 252
 253
 254 __private_extern__
 255 void
 256 server_init(mach_port_t         restart_service_port,
 257             Boolean             enableRestart)
 258 {
 259         serverSessionRef        mySession;
 260         CFRunLoopSourceRef      rls;
 261         char                    *service_name;
 262         mach_port_t             service_port    = restart_service_port;
 263         kern_return_t           status;
 264         mach_port_t             unpriv_bootstrap_port;
 265
 266         service_name = getenv("SCD_SERVER");
 267         if (!service_name) {
 268                 service_name = SCD_SERVER;
 269         }
 270
 271         if (service_port == MACH_PORT_NULL) {
 272                 mach_port_t     service_send_port;
 273
 274                 /* Check "configd" server status */
 275                 status = bootstrap_check_in(bootstrap_port, service_name, &service_port);
 276                 switch (status) {
 277                         case BOOTSTRAP_SUCCESS :
 278                                 /* if we are being restarted by launchd */
 279                                 priv_bootstrap_port = bootstrap_port;
 280                                 break;
 281                         case BOOTSTRAP_NOT_PRIVILEGED :
 282                                 /* if another instance of the server is starting */
 283                                 SCLog(TRUE, LOG_ERR, CFSTR("'%s' server already starting"), service_name);
 284                                 exit (EX_UNAVAILABLE);
 285                         case BOOTSTRAP_UNKNOWN_SERVICE :
 286                                 /* service not currently registered, "a good thing" (tm) */
 287                                 if (enableRestart) {
 288                                         status = bootstrap_create_server(bootstrap_port,
 289                                                                          "/usr/sbin/configd",
 290                                                                          geteuid(),
 291                                                                          FALSE,         /* not onDemand == restart now */
 292                                                                          &priv_bootstrap_port);
 293                                         if (status != BOOTSTRAP_SUCCESS) {
 294                                                 SCLog(TRUE, LOG_ERR,
 295                                                       CFSTR("server_init bootstrap_create_server() failed: %s"),
 296                                                       bootstrap_strerror(status));
 297                                                 exit (EX_UNAVAILABLE);
 298                                         }
 299                                 } else {
 300                                         priv_bootstrap_port = bootstrap_port;
 301                                 }
 302
 303                                 status = bootstrap_create_service(priv_bootstrap_port, service_name, &service_send_port);
 304                                 if (status != BOOTSTRAP_SUCCESS) {
 305                                         SCLog(TRUE, LOG_ERR,
 306                                               CFSTR("server_init bootstrap_create_service() failed: %s"),
 307                                               bootstrap_strerror(status));
 308                                         exit (EX_UNAVAILABLE);
 309                                 }
 310
 311                                 status = bootstrap_check_in(priv_bootstrap_port, service_name, &service_port);
 312                                 if (status != BOOTSTRAP_SUCCESS) {
 313                                         SCLog(TRUE, LOG_ERR,
 314                                               CFSTR("server_init bootstrap_check_in() failed: %s"),
 315                                               bootstrap_strerror(status));
 316                                         exit (EX_UNAVAILABLE);
 317                                 }
 318                                 break;
 319                         case BOOTSTRAP_SERVICE_ACTIVE :
 320                                 /* if another instance of the server is active */
 321                                 SCLog(TRUE, LOG_ERR, CFSTR("'%s' server already active"), service_name);
 322                                 exit (EX_UNAVAILABLE);
 323                         default :
 324                         SCLog(TRUE, LOG_ERR,
 325                               CFSTR("server_init bootstrap_check_in() failed: %s"),
 326                               bootstrap_strerror(status));
 327                         exit (EX_UNAVAILABLE);
 328                 }
 329
 330         }
 331
 332         /* we don't want to pass our priviledged bootstrap port along to any spawned helpers so... */
 333         status = bootstrap_unprivileged(priv_bootstrap_port, &unpriv_bootstrap_port);
 334         if (status != BOOTSTRAP_SUCCESS) {
 335                 SCLog(TRUE, LOG_ERR,
 336                       CFSTR("server_init bootstrap_unprivileged() failed: %s"),
 337                       bootstrap_strerror(status));
 338                 exit (EX_UNAVAILABLE);
 339         }
 340
 341         status = task_set_bootstrap_port(mach_task_self(), unpriv_bootstrap_port);
 342         if (status != BOOTSTRAP_SUCCESS) {
 343                 SCLog(TRUE, LOG_ERR,
 344                       CFSTR("server_init task_set_bootstrap_port(): %s"),
 345                       mach_error_string(status));
 346                 exit (EX_UNAVAILABLE);
 347         }
 348
 349         /* ... and make sure that the global "bootstrap_port" is also unpriviledged */
 350         bootstrap_port = unpriv_bootstrap_port;
 351
 352         /* Create the primary / new connection port and backing session */
 353         mySession = addSession(service_port, serverMPCopyDescription);
 354         configd_port = mySession->serverPort;
 355
 356         /*
 357          * Create and add a run loop source for the port and add this source
 358          * to both the default run loop mode and the "locked" mode. These two
 359          * modes will be used for normal (unlocked) communication with the
 360          * server and when multiple (locked) updates are requested by a single
 361          * session.
 362          */
 363         rls = CFMachPortCreateRunLoopSource(NULL, configd_port, 0);
 364         CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, kCFRunLoopDefaultMode);
 365         CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, CFSTR("locked"));
 366         CFRelease(rls);
 367
 368         return;
 369 }
 370
 371
 372 __private_extern__
 373 int
 374 server_shutdown()
 375 {
 376         char            *service_name;
 377         mach_port_t     service_port;
 378         kern_return_t   status;
 379
 380         /*
 381          * Note: we can't use SCLog() since the signal may be received while the
 382          *       logging thread lock is held.
 383          */
 384         if ((priv_bootstrap_port == MACH_PORT_NULL) || (configd_port == NULL)) {
 385                 return EX_OK;
 386         }
 387
 388         service_name = getenv("SCD_SERVER");
 389         if (!service_name) {
 390                 service_name = SCD_SERVER;
 391         }
 392
 393         service_port = CFMachPortGetPort(configd_port);
 394         if (service_port != MACH_PORT_NULL) {
 395                 (void) mach_port_destroy(mach_task_self(), service_port);
 396         }
 397
 398         status = bootstrap_register(priv_bootstrap_port, service_name, MACH_PORT_NULL);
 399         switch (status) {
 400                 case BOOTSTRAP_SUCCESS :
 401                         break;
 402                 case MACH_SEND_INVALID_DEST :
 403                 case MIG_SERVER_DIED :
 404                         /* something happened to launchd */
 405                         break;
 406                 default :
 407                         SCLog(TRUE, LOG_ERR,
 408                               CFSTR("server_shutdown bootstrap_register(): %s"),
 409                               bootstrap_strerror(status));
 410                         return EX_UNAVAILABLE;
 411         }
 412
 413         return EX_OK;
 414 }
 415
 416
 417 __private_extern__
 418 void
 419 server_loop()
 420 {
 421         CFStringRef     rlMode;
 422         int             rlStatus;
 423
 424         while (TRUE) {
 425                 /*
 426                  * if linked with a DEBUG version of the framework, display some
 427                  * debugging information
 428                  */
 429                 __showMachPortStatus();
 430
 431                 /*
 432                  * process one run loop event
 433                  */
 434                 rlMode = (storeLocked > 0) ? CFSTR("locked") : kCFRunLoopDefaultMode;
 435                 rlStatus = CFRunLoopRunInMode(rlMode, 1.0e10, TRUE);
 436
 437                 /*
 438                  * check for, and if necessary, push out change notifications
 439                  * to other processes.
 440                  */
 441                 pushNotifications();
 442         }
 443 }