OSX/libsecurity_utilities/lib/mach++.cpp

   1 /*
   2  * Copyright (c) 2000-2004,2011-2012,2014 Apple Inc. All Rights Reserved.
   3  *
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   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,
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  18  * Please see the License for the specific language governing rights and
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  22  */
  23
  24
  25 //
  26 // mach++ - C++ bindings for useful Mach primitives
  27 //
  28 #define __STDC_WANT_LIB_EXT1__ 1
  29 #include <string.h>
  30
  31 #include <security_utilities/mach++.h>
  32 #include <mach/mach_error.h>
  33 #include <security_utilities/debugging.h>
  34 #include <servers/bootstrap_defs.h>     // debug
  35 #include <bootstrap_priv.h>
  36
  37 namespace Security {
  38 namespace MachPlusPlus {
  39
  40
  41 //
  42 // Mach subsystem exceptions, a subclass of CssmCommonError
  43 //
  44 Error::Error(kern_return_t err) : error(err)
  45 {
  46     SECURITY_EXCEPTION_THROW_MACH(this, err);
  47     secnotice("security_exception", "mach error: %d", err);
  48 }
  49
  50 Error::~Error() throw()
  51 { }
  52
  53
  54 OSStatus Error::osStatus() const
  55 {
  56         switch (error) {
  57         case MIG_BAD_ARGUMENTS:
  58         case MIG_TYPE_ERROR:
  59         case MIG_REMOTE_ERROR:
  60                 return errSecServiceNotAvailable;               // IPC mismatch of some sort
  61         default:
  62                 return -1;              //@@@ some "internal error" code, perhaps?
  63         }
  64 }
  65
  66 int Error::unixError() const
  67 {
  68         switch (error) {
  69         case MIG_BAD_ARGUMENTS:
  70         case MIG_TYPE_ERROR:
  71         case MIG_REMOTE_ERROR:
  72                 return ERPCMISMATCH;            // IPC mismatch of some sort
  73         default:
  74                 return -1;              //@@@ some "internal error" code, perhaps?
  75         }
  76 }
  77
  78 void Error::check(kern_return_t status)
  79 {
  80         if (status != KERN_SUCCESS)
  81                 Error::throwMe(status);
  82 }
  83
  84 void Error::throwMe(kern_return_t err)
  85 {
  86         throw Error(err);
  87 }
  88
  89
  90 //
  91 // Memory management
  92 //
  93 void *allocate(size_t size)
  94 {
  95         vm_address_t address;
  96         check(vm_allocate(mach_task_self(), &address, size, true));
  97         return reinterpret_cast<void *>(address);
  98 }
  99
 100 void deallocate(vm_address_t address, size_t size)
 101 {
 102         check(vm_deallocate(mach_task_self(), address, size));
 103 }
 104
 105
 106 //
 107 // Port functions
 108 //
 109 mach_port_urefs_t Port::getRefs(mach_port_right_t right)
 110 {
 111         mach_port_urefs_t count;
 112         check(::mach_port_get_refs(self(), mPort, right, &count));
 113         return count;
 114 }
 115
 116 mach_port_t Port::requestNotify(mach_port_t notify, mach_msg_id_t type, mach_port_mscount_t sync)
 117 {
 118     mach_port_t previous;
 119     check(mach_port_request_notification(self(), mPort, type, sync, notify,
 120         MACH_MSG_TYPE_MAKE_SEND_ONCE, &previous));
 121
 122 #if !defined(NDEBUG)
 123         const char *typeName;
 124         switch (type) {
 125         case MACH_NOTIFY_PORT_DELETED:  typeName = "port deleted"; break;
 126         case MACH_NOTIFY_PORT_DESTROYED:typeName = "port destroyed"; break;
 127         case MACH_NOTIFY_NO_SENDERS:    typeName = "no senders"; break;
 128         case MACH_NOTIFY_SEND_ONCE:             typeName = "send once"; break;
 129         case MACH_NOTIFY_DEAD_NAME:             typeName = "dead name"; break;
 130         default:                                                typeName = "???"; break;
 131         }
 132         if (notify == MACH_PORT_NULL)
 133                 secinfo("port", "%d cancel notify %s", port(), typeName);
 134         else
 135                 secinfo("port", "%d request notify %s to %d (sync %d)", port(), typeName, notify, sync);
 136 #endif //!NDEBUG
 137
 138     return previous;
 139 }
 140
 141 mach_port_t Port::cancelNotify(mach_msg_id_t type)
 142 {
 143     // Mach won't let us unset the DPN port if we are already dead
 144     // (EVEN if the DPN has already been sent!) So just ignore that case...
 145     if (isDead())
 146         return MACH_PORT_NULL;
 147         return requestNotify(MACH_PORT_NULL, type);
 148 }
 149
 150 mach_port_msgcount_t Port::qlimit() const
 151 {
 152         mach_port_limits_t limits;
 153         mach_msg_type_number_t infoCount = 1;
 154         check(::mach_port_get_attributes(self(), mPort, MACH_PORT_LIMITS_INFO,
 155                 mach_port_info_t(&limits), &infoCount));
 156         assert(infoCount == 1);
 157         return limits.mpl_qlimit;
 158 }
 159
 160 void Port::qlimit(mach_port_msgcount_t limit)
 161 {
 162         mach_port_limits_t limits;
 163         limits.mpl_qlimit = limit;
 164         check(::mach_port_set_attributes(self(), mPort, MACH_PORT_LIMITS_INFO,
 165                 mach_port_info_t(&limits), MACH_PORT_LIMITS_INFO_COUNT));
 166 }
 167
 168
 169 //
 170 // PortSet features
 171 //
 172 set<Port> PortSet::members() const
 173 {
 174         mach_port_array_t members;
 175         mach_msg_type_number_t count;
 176         check(::mach_port_get_set_status(self(), mPort, &members, &count));
 177         try {
 178                 set<Port> result;
 179                 copy(members, members+count, inserter(result, result.begin()));
 180                 vm_deallocate(self(), vm_address_t(members), count * sizeof(members[0]));
 181                 return result;
 182         } catch (...) {
 183                 vm_deallocate(self(), vm_address_t(members), count * sizeof(members[0]));
 184                 throw;
 185         }
 186 }
 187
 188
 189 bool PortSet::contains(Port member) const
 190 {
 191         set<Port> memberSet = members();
 192         return memberSet.find(member) != memberSet.end();
 193 }
 194
 195
 196 //
 197 // Task port features
 198 //
 199 TaskPort::TaskPort(pid_t pid)
 200 {
 201         check(::task_for_pid(self(), pid, &mPort));
 202 }
 203
 204 pid_t TaskPort::pid() const
 205 {
 206     pid_t pid;
 207     check(::pid_for_task(mPort, &pid));
 208     return pid;
 209 }
 210
 211
 212 //
 213 // Bootstrap port management
 214 //
 215 mach_port_t Bootstrap::checkIn(const char *name) const
 216 {
 217         mach_port_t port;
 218         check(::bootstrap_check_in(mPort, makeName(name), &port));
 219         return port;
 220 }
 221
 222 mach_port_t Bootstrap::checkInOptional(const char *name) const
 223 {
 224         mach_port_t port;
 225         switch (kern_return_t err = ::bootstrap_check_in(mPort, makeName(name), &port)) {
 226         case BOOTSTRAP_SERVICE_ACTIVE:
 227     case BOOTSTRAP_UNKNOWN_SERVICE:
 228         case BOOTSTRAP_NOT_PRIVILEGED:
 229         return MACH_PORT_NULL;
 230         default:
 231                 check(err);
 232         }
 233         return port;
 234 }
 235
 236 void Bootstrap::registerAs(mach_port_t port, const char *name) const
 237 {
 238         secinfo("bootstrap", "creating service port %d in %d:%s", port, this->port(), name);
 239         check(::bootstrap_register(mPort, makeName(name), port));
 240 }
 241
 242 mach_port_t Bootstrap::lookup(const char *name) const
 243 {
 244         mach_port_t port;
 245         check(::bootstrap_look_up(mPort, makeName(name), &port));
 246         return port;
 247 }
 248
 249 mach_port_t Bootstrap::lookup2(const char *name) const
 250 {
 251         mach_port_t port;
 252         check(::bootstrap_look_up2(mPort, makeName(name), &port, 0, BOOTSTRAP_PRIVILEGED_SERVER));
 253         return port;
 254 }
 255
 256 mach_port_t Bootstrap::lookupOptional(const char *name) const
 257 {
 258         mach_port_t port;
 259         kern_return_t err = ::bootstrap_look_up(mPort, makeName(name), &port);
 260     if (err == BOOTSTRAP_UNKNOWN_SERVICE)
 261         return 0;
 262     check(err);
 263         return port;
 264 }
 265
 266
 267 Bootstrap Bootstrap::subset(Port requestor)
 268 {
 269     mach_port_t sub;
 270     check(::bootstrap_subset(mPort, requestor, &sub));
 271     return sub;
 272 }
 273
 274
 275 //
 276 // ReceivePorts
 277 //
 278 ReceivePort::ReceivePort(const char *name, const Bootstrap &bootstrap, bool tryCheckin /* = true */)
 279 {
 280         if (tryCheckin)
 281                 mPort = bootstrap.checkInOptional(name);
 282         if (!mPort) {
 283                 allocate();
 284                 // Bootstrap registration requires a send right to (copy) send.
 285                 // Make a temporary one, send it, then take it away again, to avoid
 286                 // messing up the caller's send right accounting.
 287                 insertRight(MACH_MSG_TYPE_MAKE_SEND);
 288                 bootstrap.registerAs(mPort, name);
 289                 modRefs(MACH_PORT_RIGHT_SEND, -1);
 290         }
 291 }
 292
 293
 294 //
 295 // Stack-based bootstrap switcher
 296 //
 297 ModuleNexus<Mutex> StBootstrap::critical;
 298
 299 StBootstrap::StBootstrap(const Bootstrap &newBoot, const TaskPort &task)
 300     : mTask(task), locker(critical())
 301 {
 302     mOldBoot = Bootstrap();
 303     mTask.bootstrap(newBoot);
 304     secinfo("StBoot", "bootstrap for %d switched to %d", mTask.port(), newBoot.port());
 305 }
 306
 307 StBootstrap::~StBootstrap()
 308 {
 309     mTask.bootstrap(mOldBoot);
 310     secinfo("StBoot", "bootstrap for %d returned to %d", mTask.port(), mOldBoot.port());
 311 }
 312
 313
 314 //
 315 // Mach message buffers
 316 //
 317 Message::Message(void *buffer, mach_msg_size_t size)
 318         : mBuffer(NULL), mRelease(false)
 319 {
 320         setBuffer(buffer, size);
 321 }
 322
 323 Message::Message(mach_msg_size_t size)
 324         : mBuffer(NULL), mRelease(false)
 325 {
 326         setBuffer(size);
 327 }
 328
 329 Message::Message()
 330         : mBuffer(NULL), mRelease(false)
 331 { }
 332
 333
 334 Message::~Message()
 335 {
 336         release();
 337 }
 338
 339
 340 void Message::setBuffer(void *buffer, mach_msg_size_t size)
 341 {
 342         release();
 343         mBuffer = reinterpret_cast<mig_reply_error_t *>(buffer);
 344         mSize = size;
 345         mRelease = false;
 346 }
 347
 348 void Message::setBuffer(mach_msg_size_t size)
 349 {
 350         assert(size >= sizeof(mach_msg_header_t));
 351         release();
 352         mSize = size + MAX_TRAILER_SIZE;
 353         mBuffer = reinterpret_cast<mig_reply_error_t *>(new char[mSize]());
 354         mRelease = true;
 355 }
 356
 357 void Message::clearBuffer(void)
 358 {
 359     (void)memset_s(mBuffer, mSize, 0, mSize);
 360 }
 361
 362 void Message::release()
 363 {
 364         if (mRelease)
 365                 delete[] reinterpret_cast<char *>(mBuffer);
 366 }
 367
 368
 369 bool Message::check(kern_return_t status)
 370 {
 371     switch (status) {
 372     case KERN_SUCCESS:
 373         return true;
 374     case MACH_RCV_TIMED_OUT:
 375     case MACH_SEND_TIMED_OUT:
 376         return false;
 377     default:
 378         Error::throwMe(status);
 379     }
 380 }
 381
 382
 383 bool Message::send(mach_msg_option_t options,
 384     mach_msg_timeout_t timeout,
 385     mach_port_name_t notify)
 386 {
 387     return check(mach_msg_overwrite(*this,
 388         options | MACH_SEND_MSG,
 389         length(),
 390         0, MACH_PORT_NULL,
 391         timeout, notify,
 392         NULL, 0));
 393 }
 394
 395 bool Message::receive(mach_port_t receivePort,
 396     mach_msg_option_t options,
 397     mach_msg_timeout_t timeout,
 398     mach_port_name_t notify)
 399 {
 400     return check(mach_msg_overwrite(*this,
 401         options | MACH_RCV_MSG,
 402         length(),
 403         mSize, receivePort,
 404         timeout, notify,
 405         NULL, 0));
 406 }
 407
 408 bool Message::sendReceive(mach_port_t receivePort,
 409     mach_msg_option_t options,
 410     mach_msg_timeout_t timeout,
 411     mach_port_name_t notify)
 412 {
 413     return check(mach_msg_overwrite(*this,
 414         options | MACH_SEND_MSG | MACH_RCV_MSG,
 415         length(),
 416         mSize, receivePort,
 417         timeout, notify,
 418         NULL, 0));
 419 }
 420
 421 /* cribbed from libdispatch: _dispatch_mach_msg_get_audit_trailer */
 422 mach_msg_audit_trailer_t *
 423 Message::auditTrailer()
 424 {
 425     mach_msg_header_t *hdr = &mBuffer->Head;
 426     mach_msg_trailer_t *tlr = NULL;
 427     mach_msg_audit_trailer_t *audit_tlr = NULL;
 428     tlr = (mach_msg_trailer_t *)((unsigned char *)hdr +
 429             round_msg(hdr->msgh_size));
 430     // The trailer should always be of format zero.
 431     if (tlr->msgh_trailer_type == MACH_MSG_TRAILER_FORMAT_0) {
 432         if (tlr->msgh_trailer_size >= sizeof(mach_msg_audit_trailer_t)) {
 433             audit_tlr = (mach_msg_audit_trailer_t *)tlr;
 434         }
 435     }
 436     return audit_tlr;
 437 }
 438
 439 //
 440 // Debug dumping of ports etc.
 441 //
 442 #if defined(DEBUGDUMP)
 443
 444 void Port::dump(const char *descr)
 445 {
 446     if (mPort == MACH_PORT_NULL) {
 447         Debug::dump("[%s==NULL]\n", descr ? descr : "port");
 448     } else {
 449         Debug::dump("[%s(%d)", descr ? descr : "port", mPort);
 450         mach_port_type_t type;
 451         if (kern_return_t err = mach_port_type(self(), mPort, &type)) {
 452             Debug::dump(" !%s", mach_error_string(err));
 453         } else {
 454             if (type & MACH_PORT_TYPE_SEND)
 455                 Debug::dump(" send(%d)", getRefs(MACH_PORT_RIGHT_SEND));
 456             if (type & MACH_PORT_TYPE_RECEIVE)
 457                 Debug::dump(" rcv");
 458             if (type & MACH_PORT_TYPE_SEND_ONCE)
 459                 Debug::dump(" once(%d)", getRefs(MACH_PORT_RIGHT_SEND));
 460             if (type & MACH_PORT_TYPE_PORT_SET)
 461                 Debug::dump(" set");
 462             if (type & MACH_PORT_TYPE_DEAD_NAME)
 463                 Debug::dump(" dead(%d)", getRefs(MACH_PORT_RIGHT_SEND));
 464             if (type & MACH_PORT_TYPE_DNREQUEST)
 465                 Debug::dump(" dnreq");
 466             // handle unknown/unexpected type flags
 467             if (type & ~(MACH_PORT_TYPE_SEND|MACH_PORT_TYPE_RECEIVE|MACH_PORT_TYPE_SEND_ONCE|
 468                     MACH_PORT_TYPE_PORT_SET|MACH_PORT_TYPE_DEAD_NAME|MACH_PORT_TYPE_DNREQUEST))
 469                 Debug::dump(" type(0x%x)", type);
 470         }
 471         Debug::dump("]\n");
 472     }
 473 }
 474
 475
 476 #endif //DEBUGDUMP
 477
 478
 479 } // end namespace MachPlusPlus
 480 } // end namespace Security