configd.tproj/configd_server.c

   1 /*
   2  * Copyright (c) 2000-2009 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 __private_extern__
  62 boolean_t
  63 config_demux(mach_msg_header_t *request, mach_msg_header_t *reply)
  64 {
  65         Boolean                         processed = FALSE;
  66
  67         /*
  68          * (attempt to) process SCDynamicStore requests.
  69          */
  70         processed = config_server(request, reply);
  71         if (processed) {
  72                 return TRUE;
  73         }
  74
  75         /*
  76          * (attempt to) process DNS configuration requests.
  77          */
  78         processed = shared_dns_info_server(request, reply);
  79         if (processed) {
  80                 return TRUE;
  81         }
  82
  83         /*
  84          * (attempt to) process (NO MORE SENDERS) notification messages.
  85          */
  86         processed = notify_server(request, reply);
  87         if (processed) {
  88                 return TRUE;
  89         }
  90
  91         /*
  92          * unknown message ID, log and return an error.
  93          */
  94         SCLog(TRUE, LOG_ERR, CFSTR("config_demux(): unknown message ID (%d) received"), request->msgh_id);
  95         reply->msgh_bits        = MACH_MSGH_BITS(MACH_MSGH_BITS_REMOTE(request->msgh_bits), 0);
  96         reply->msgh_remote_port = request->msgh_remote_port;
  97         reply->msgh_size        = sizeof(mig_reply_error_t);    /* Minimal size */
  98         reply->msgh_local_port  = MACH_PORT_NULL;
  99         reply->msgh_id          = request->msgh_id + 100;
 100         ((mig_reply_error_t *)reply)->NDR = NDR_record;
 101         ((mig_reply_error_t *)reply)->RetCode = MIG_BAD_ID;
 102
 103         return FALSE;
 104 }
 105
 106
 107 #define MACH_MSG_BUFFER_SIZE    128
 108
 109
 110 __private_extern__
 111 void
 112 configdCallback(CFMachPortRef port, void *msg, CFIndex size, void *info)
 113 {
 114         mig_reply_error_t *     bufRequest      = msg;
 115         uint32_t                bufReply_q[MACH_MSG_BUFFER_SIZE/sizeof(uint32_t)];
 116         mig_reply_error_t *     bufReply        = (mig_reply_error_t *)bufReply_q;
 117         static CFIndex          bufSize         = 0;
 118         mach_msg_return_t       mr;
 119         int                     options;
 120
 121         if (bufSize == 0) {
 122                 // get max size for MiG reply buffers
 123                 bufSize = _config_subsystem.maxsize;
 124                 if (_shared_dns_info_subsystem.maxsize > bufSize) {
 125                         bufSize = _shared_dns_info_subsystem.maxsize;
 126                 }
 127
 128                 // check if our on-the-stack reply buffer will be big enough
 129                 if (bufSize > sizeof(bufReply_q)) {
 130                         SCLog(TRUE, LOG_NOTICE,
 131                               CFSTR("configdCallback(): buffer size should be increased > %d"),
 132                               _config_subsystem.maxsize);
 133                 }
 134         }
 135
 136         if (bufSize > sizeof(bufReply_q)) {
 137                 bufReply = CFAllocatorAllocate(NULL, _config_subsystem.maxsize, 0);
 138         }
 139
 140         /* we have a request message */
 141         (void) config_demux(&bufRequest->Head, &bufReply->Head);
 142
 143         if (!(bufReply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)) {
 144                 if (bufReply->RetCode == MIG_NO_REPLY) {
 145                         bufReply->Head.msgh_remote_port = MACH_PORT_NULL;
 146                 } else if ((bufReply->RetCode != KERN_SUCCESS) &&
 147                            (bufRequest->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)) {
 148                         /*
 149                          * destroy the request - but not the reply port
 150                          */
 151                         bufRequest->Head.msgh_remote_port = MACH_PORT_NULL;
 152                         mach_msg_destroy(&bufRequest->Head);
 153                 }
 154         }
 155
 156         if (bufReply->Head.msgh_remote_port != MACH_PORT_NULL) {
 157                 /*
 158                  * send reply.
 159                  *
 160                  * We don't want to block indefinitely because the client
 161                  * isn't receiving messages from the reply port.
 162                  * If we have a send-once right for the reply port, then
 163                  * this isn't a concern because the send won't block.
 164                  * If we have a send right, we need to use MACH_SEND_TIMEOUT.
 165                  * To avoid falling off the kernel's fast RPC path unnecessarily,
 166                  * we only supply MACH_SEND_TIMEOUT when absolutely necessary.
 167                  */
 168
 169                 options = MACH_SEND_MSG;
 170                 if (MACH_MSGH_BITS_REMOTE(bufReply->Head.msgh_bits) != MACH_MSG_TYPE_MOVE_SEND_ONCE) {
 171                         options |= MACH_SEND_TIMEOUT;
 172                 }
 173                 mr = mach_msg(&bufReply->Head,          /* msg */
 174                               options,                  /* option */
 175                               bufReply->Head.msgh_size, /* send_size */
 176                               0,                        /* rcv_size */
 177                               MACH_PORT_NULL,           /* rcv_name */
 178                               MACH_MSG_TIMEOUT_NONE,    /* timeout */
 179                               MACH_PORT_NULL);          /* notify */
 180
 181                 /* Has a message error occurred? */
 182                 switch (mr) {
 183                         case MACH_SEND_INVALID_DEST:
 184                         case MACH_SEND_TIMED_OUT:
 185                                 break;
 186                         default :
 187                                 /* Includes success case.  */
 188                                 goto done;
 189                 }
 190         }
 191
 192         if (bufReply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX) {
 193                 mach_msg_destroy(&bufReply->Head);
 194         }
 195
 196     done :
 197
 198         if (bufReply != (mig_reply_error_t *)bufReply_q)
 199                 CFAllocatorDeallocate(NULL, bufReply);
 200         return;
 201 }
 202
 203
 204 static CFStringRef
 205 serverMPCopyDescription(const void *info)
 206 {
 207         return CFStringCreateWithFormat(NULL, NULL, CFSTR("<main DynamicStore MP>"));
 208 }
 209
 210
 211 __private_extern__
 212 void
 213 server_init()
 214 {
 215         serverSessionRef        mySession;
 216         CFRunLoopSourceRef      rls;
 217         char                    *service_name;
 218         mach_port_t             service_port    = MACH_PORT_NULL;
 219         kern_return_t           status;
 220
 221         service_name = getenv("SCD_SERVER");
 222         if (!service_name) {
 223                 service_name = SCD_SERVER;
 224         }
 225
 226         /* Check "configd" server status */
 227         status = bootstrap_check_in(bootstrap_port, service_name, &service_port);
 228         switch (status) {
 229                 case BOOTSTRAP_SUCCESS :
 230                         /* if we are being [re-]started by launchd */
 231                         break;
 232                 case BOOTSTRAP_NOT_PRIVILEGED :
 233                         /* if another instance of the server is starting */
 234                         SCLog(TRUE, LOG_ERR, CFSTR("'%s' server already starting"), service_name);
 235                         exit (EX_UNAVAILABLE);
 236                 case BOOTSTRAP_SERVICE_ACTIVE :
 237                         /* if another instance of the server is active */
 238                         SCLog(TRUE, LOG_ERR, CFSTR("'%s' server already active"), service_name);
 239                         exit (EX_UNAVAILABLE);
 240                 default :
 241                         SCLog(TRUE, LOG_ERR,
 242                               CFSTR("server_init bootstrap_check_in() failed: %s"),
 243                               bootstrap_strerror(status));
 244                         exit (EX_UNAVAILABLE);
 245         }
 246
 247         /* Create the primary / new connection port and backing session */
 248         mySession = addSession(service_port, serverMPCopyDescription);
 249         configd_port = mySession->serverPort;
 250
 251         /*
 252          * Create and add a run loop source for the port and add this source
 253          * to both the default run loop mode and the "locked" mode. These two
 254          * modes will be used for normal (unlocked) communication with the
 255          * server and when multiple (locked) updates are requested by a single
 256          * session.
 257          */
 258         rls = CFMachPortCreateRunLoopSource(NULL, configd_port, 0);
 259         CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, kCFRunLoopDefaultMode);
 260         CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, CFSTR("locked"));
 261         CFRelease(rls);
 262
 263         return;
 264 }
 265
 266
 267 __private_extern__
 268 int
 269 server_shutdown()
 270 {
 271         if (configd_port != NULL) {
 272                 mach_port_t     service_port;
 273
 274                 service_port = CFMachPortGetPort(configd_port);
 275                 if (service_port != MACH_PORT_NULL) {
 276                         (void) mach_port_mod_refs(mach_task_self(),
 277                                                   service_port,
 278                                                   MACH_PORT_RIGHT_RECEIVE,
 279                                                   -1);
 280                 }
 281
 282                 CFMachPortInvalidate(configd_port);
 283                 CFRelease(configd_port);
 284                 configd_port = NULL;
 285         }
 286
 287         return EX_OK;
 288 }
 289
 290
 291 __private_extern__
 292 void
 293 server_loop()
 294 {
 295         CFStringRef     rlMode;
 296
 297         while (TRUE) {
 298                 /*
 299                  * process one run loop event
 300                  */
 301                 rlMode = (storeLocked > 0) ? CFSTR("locked") : kCFRunLoopDefaultMode;
 302                 CFRunLoopRunInMode(rlMode, 1.0e10, TRUE);
 303
 304                 /*
 305                  * check for, and if necessary, push out change notifications
 306                  * to other processes.
 307                  */
 308                 pushNotifications(_configd_trace);
 309         }
 310 }