server/mach.c

   1 /*
   2  * Server-side debugger support using Mach primitives
   3  *
   4  * Copyright (C) 1999, 2006 Alexandre Julliard
   5  * Copyright (C) 2006 Ken Thomases for CodeWeavers
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include "config.h"
  23
  24 #include <assert.h>
  25 #include <errno.h>
  26 #include <stdio.h>
  27 #include <signal.h>
  28 #include <stdarg.h>
  29 #include <sys/types.h>
  30 #include <unistd.h>
  31 #ifdef HAVE_SYS_SYSCALL_H
  32 #include <sys/syscall.h>
  33 #endif
  34 #ifdef HAVE_SYS_SYSCTL_H
  35 #include <sys/sysctl.h>
  36 #endif
  37
  38 #include "ntstatus.h"
  39 #define WIN32_NO_STATUS
  40 #include "winternl.h"
  41
  42 #include "file.h"
  43 #include "process.h"
  44 #include "thread.h"
  45 #include "request.h"
  46
  47 #ifdef USE_MACH
  48
  49 #include <mach/mach.h>
  50 #include <mach/mach_error.h>
  51 #include <mach/thread_act.h>
  52 #include <mach/mach_vm.h>
  53 #include <servers/bootstrap.h>
  54
  55 static mach_port_t server_mach_port;
  56
  57 void sigchld_callback(void)
  58 {
  59     assert(0);  /* should never be called on MacOS */
  60 }
  61
  62 static void mach_set_error(kern_return_t mach_error)
  63 {
  64     switch (mach_error)
  65     {
  66         case KERN_SUCCESS:              break;
  67         case KERN_INVALID_ARGUMENT:     set_error(STATUS_INVALID_PARAMETER); break;
  68         case KERN_NO_SPACE:             set_error(STATUS_NO_MEMORY); break;
  69         case KERN_PROTECTION_FAILURE:   set_error(STATUS_ACCESS_DENIED); break;
  70         case KERN_INVALID_ADDRESS:      set_error(STATUS_ACCESS_VIOLATION); break;
  71         default:                        set_error(STATUS_UNSUCCESSFUL); break;
  72     }
  73 }
  74
  75 static mach_port_t get_process_port( struct process *process )
  76 {
  77     return process->trace_data;
  78 }
  79
  80 static int is_rosetta( void )
  81 {
  82     static int rosetta_status, did_check = 0;
  83     if (!did_check)
  84     {
  85         /* returns 0 for native process or on error, 1 for translated */
  86         int ret = 0;
  87         size_t size = sizeof(ret);
  88         if (sysctlbyname( "sysctl.proc_translated", &ret, &size, NULL, 0 ) == -1)
  89             rosetta_status = 0;
  90         else
  91             rosetta_status = ret;
  92
  93         did_check = 1;
  94     }
  95
  96     return rosetta_status;
  97 }
  98
  99 /* initialize the process control mechanism */
 100 void init_tracing_mechanism(void)
 101 {
 102     mach_port_t bp;
 103
 104     if (task_get_bootstrap_port(mach_task_self(), &bp) != KERN_SUCCESS)
 105         fatal_error("Can't find bootstrap port\n");
 106     if (mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &server_mach_port) != KERN_SUCCESS)
 107         fatal_error("Can't allocate port\n");
 108     if  (mach_port_insert_right( mach_task_self(),
 109                                  server_mach_port,
 110                                  server_mach_port,
 111                                  MACH_MSG_TYPE_MAKE_SEND ) != KERN_SUCCESS)
 112             fatal_error("Error inserting rights\n");
 113     if (bootstrap_register(bp, server_dir, server_mach_port) != KERN_SUCCESS)
 114         fatal_error("Can't check in server_mach_port\n");
 115     mach_port_deallocate(mach_task_self(), bp);
 116 }
 117
 118 /* initialize the per-process tracing mechanism */
 119 void init_process_tracing( struct process *process )
 120 {
 121     int pid, ret;
 122     struct
 123     {
 124         mach_msg_header_t           header;
 125         mach_msg_body_t             body;
 126         mach_msg_port_descriptor_t  task_port;
 127         mach_msg_trailer_t          trailer; /* only present on receive */
 128     } msg;
 129
 130     for (;;)
 131     {
 132         ret = mach_msg( &msg.header, MACH_RCV_MSG|MACH_RCV_TIMEOUT, 0, sizeof(msg),
 133                         server_mach_port, 0, 0 );
 134         if (ret)
 135         {
 136             if (ret != MACH_RCV_TIMED_OUT && debug_level)
 137                 fprintf( stderr, "warning: mach port receive failed with %x\n", ret );
 138             return;
 139         }
 140
 141         /* if anything in the message is invalid, ignore it */
 142         if (msg.header.msgh_size != offsetof(typeof(msg), trailer)) continue;
 143         if (msg.body.msgh_descriptor_count != 1) continue;
 144         if (msg.task_port.type != MACH_MSG_PORT_DESCRIPTOR) continue;
 145         if (msg.task_port.disposition != MACH_MSG_TYPE_PORT_SEND) continue;
 146         if (msg.task_port.name == MACH_PORT_NULL) continue;
 147         if (msg.task_port.name == MACH_PORT_DEAD) continue;
 148
 149         if (!pid_for_task( msg.task_port.name, &pid ))
 150         {
 151             struct thread *thread = get_thread_from_pid( pid );
 152
 153             if (thread && !thread->process->trace_data)
 154                 thread->process->trace_data = msg.task_port.name;
 155             else
 156                 mach_port_deallocate( mach_task_self(), msg.task_port.name );
 157         }
 158     }
 159 }
 160
 161 /* terminate the per-process tracing mechanism */
 162 void finish_process_tracing( struct process *process )
 163 {
 164     if (process->trace_data)
 165     {
 166         mach_port_deallocate( mach_task_self(), process->trace_data );
 167         process->trace_data = 0;
 168     }
 169 }
 170
 171 /* initialize registers in new thread if necessary */
 172 void init_thread_context( struct thread *thread )
 173 {
 174 }
 175
 176 /* retrieve the thread x86 registers */
 177 void get_thread_context( struct thread *thread, context_t *context, unsigned int flags )
 178 {
 179 #if defined(__i386__) || defined(__x86_64__)
 180     x86_debug_state_t state;
 181     mach_msg_type_number_t count = sizeof(state) / sizeof(int);
 182     mach_msg_type_name_t type;
 183     mach_port_t port, process_port = get_process_port( thread->process );
 184     kern_return_t ret;
 185     unsigned long dr[8];
 186
 187     /* all other regs are handled on the client side */
 188     assert( flags == SERVER_CTX_DEBUG_REGISTERS );
 189
 190     if (is_rosetta())
 191     {
 192         /* getting debug registers of a translated process is not supported cross-process, return all zeroes */
 193         memset( &context->debug, 0, sizeof(context->debug) );
 194         context->flags |= SERVER_CTX_DEBUG_REGISTERS;
 195         return;
 196     }
 197
 198     if (thread->unix_pid == -1 || !process_port ||
 199         mach_port_extract_right( process_port, thread->unix_tid,
 200                                  MACH_MSG_TYPE_COPY_SEND, &port, &type ))
 201     {
 202         set_error( STATUS_ACCESS_DENIED );
 203         return;
 204     }
 205
 206     ret = thread_get_state( port, x86_DEBUG_STATE, (thread_state_t)&state, &count );
 207     if (!ret)
 208     {
 209         assert( state.dsh.flavor == x86_DEBUG_STATE32 ||
 210                 state.dsh.flavor == x86_DEBUG_STATE64 );
 211
 212         if (state.dsh.flavor == x86_DEBUG_STATE64)
 213         {
 214             dr[0] = state.uds.ds64.__dr0;
 215             dr[1] = state.uds.ds64.__dr1;
 216             dr[2] = state.uds.ds64.__dr2;
 217             dr[3] = state.uds.ds64.__dr3;
 218             dr[6] = state.uds.ds64.__dr6;
 219             dr[7] = state.uds.ds64.__dr7;
 220         }
 221         else
 222         {
 223             dr[0] = state.uds.ds32.__dr0;
 224             dr[1] = state.uds.ds32.__dr1;
 225             dr[2] = state.uds.ds32.__dr2;
 226             dr[3] = state.uds.ds32.__dr3;
 227             dr[6] = state.uds.ds32.__dr6;
 228             dr[7] = state.uds.ds32.__dr7;
 229         }
 230
 231         switch (context->machine)
 232         {
 233         case IMAGE_FILE_MACHINE_I386:
 234             context->debug.i386_regs.dr0 = dr[0];
 235             context->debug.i386_regs.dr1 = dr[1];
 236             context->debug.i386_regs.dr2 = dr[2];
 237             context->debug.i386_regs.dr3 = dr[3];
 238             context->debug.i386_regs.dr6 = dr[6];
 239             context->debug.i386_regs.dr7 = dr[7];
 240             break;
 241         case IMAGE_FILE_MACHINE_AMD64:
 242             context->debug.x86_64_regs.dr0 = dr[0];
 243             context->debug.x86_64_regs.dr1 = dr[1];
 244             context->debug.x86_64_regs.dr2 = dr[2];
 245             context->debug.x86_64_regs.dr3 = dr[3];
 246             context->debug.x86_64_regs.dr6 = dr[6];
 247             context->debug.x86_64_regs.dr7 = dr[7];
 248             break;
 249         default:
 250             set_error( STATUS_INVALID_PARAMETER );
 251             goto done;
 252         }
 253         context->flags |= SERVER_CTX_DEBUG_REGISTERS;
 254     }
 255     else
 256         mach_set_error( ret );
 257 done:
 258     mach_port_deallocate( mach_task_self(), port );
 259 #endif
 260 }
 261
 262 /* set the thread x86 registers */
 263 void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
 264 {
 265 #if defined(__i386__) || defined(__x86_64__)
 266     x86_debug_state_t state;
 267     mach_msg_type_number_t count = sizeof(state) / sizeof(int);
 268     mach_msg_type_name_t type;
 269     mach_port_t port, process_port = get_process_port( thread->process );
 270     unsigned long dr[8];
 271     kern_return_t ret;
 272
 273     /* all other regs are handled on the client side */
 274     assert( flags == SERVER_CTX_DEBUG_REGISTERS );
 275
 276     if (is_rosetta())
 277     {
 278         /* Setting debug registers of a translated process is not supported cross-process
 279          * (and even in-process, setting debug registers never has the desired effect).
 280          */
 281         set_error( STATUS_UNSUCCESSFUL );
 282         return;
 283     }
 284
 285     if (thread->unix_pid == -1 || !process_port ||
 286         mach_port_extract_right( process_port, thread->unix_tid,
 287                                  MACH_MSG_TYPE_COPY_SEND, &port, &type ))
 288     {
 289         set_error( STATUS_ACCESS_DENIED );
 290         return;
 291     }
 292
 293     /* get the debug state to determine which flavor to use */
 294     ret = thread_get_state(port, x86_DEBUG_STATE, (thread_state_t)&state, &count);
 295     if (ret)
 296     {
 297         mach_set_error( ret );
 298         goto done;
 299     }
 300     assert( state.dsh.flavor == x86_DEBUG_STATE32 ||
 301             state.dsh.flavor == x86_DEBUG_STATE64 );
 302
 303     switch (context->machine)
 304     {
 305         case IMAGE_FILE_MACHINE_I386:
 306             dr[0] = context->debug.i386_regs.dr0;
 307             dr[1] = context->debug.i386_regs.dr1;
 308             dr[2] = context->debug.i386_regs.dr2;
 309             dr[3] = context->debug.i386_regs.dr3;
 310             dr[6] = context->debug.i386_regs.dr6;
 311             dr[7] = context->debug.i386_regs.dr7;
 312             break;
 313         case IMAGE_FILE_MACHINE_AMD64:
 314             dr[0] = context->debug.x86_64_regs.dr0;
 315             dr[1] = context->debug.x86_64_regs.dr1;
 316             dr[2] = context->debug.x86_64_regs.dr2;
 317             dr[3] = context->debug.x86_64_regs.dr3;
 318             dr[6] = context->debug.x86_64_regs.dr6;
 319             dr[7] = context->debug.x86_64_regs.dr7;
 320             break;
 321         default:
 322             set_error( STATUS_INVALID_PARAMETER );
 323             goto done;
 324     }
 325
 326     /* Mac OS doesn't allow setting the global breakpoint flags */
 327     dr[7] = (dr[7] & ~0xaa) | ((dr[7] & 0xaa) >> 1);
 328
 329     if (state.dsh.flavor == x86_DEBUG_STATE64)
 330     {
 331         state.dsh.count = sizeof(state.uds.ds64) / sizeof(int);
 332         state.uds.ds64.__dr0 = dr[0];
 333         state.uds.ds64.__dr1 = dr[1];
 334         state.uds.ds64.__dr2 = dr[2];
 335         state.uds.ds64.__dr3 = dr[3];
 336         state.uds.ds64.__dr4 = 0;
 337         state.uds.ds64.__dr5 = 0;
 338         state.uds.ds64.__dr6 = dr[6];
 339         state.uds.ds64.__dr7 = dr[7];
 340     }
 341     else
 342     {
 343         state.dsh.count = sizeof(state.uds.ds32) / sizeof(int);
 344         state.uds.ds32.__dr0 = dr[0];
 345         state.uds.ds32.__dr1 = dr[1];
 346         state.uds.ds32.__dr2 = dr[2];
 347         state.uds.ds32.__dr3 = dr[3];
 348         state.uds.ds32.__dr4 = 0;
 349         state.uds.ds32.__dr5 = 0;
 350         state.uds.ds32.__dr6 = dr[6];
 351         state.uds.ds32.__dr7 = dr[7];
 352     }
 353     ret = thread_set_state( port, x86_DEBUG_STATE, (thread_state_t)&state, count );
 354     if (ret)
 355         mach_set_error( ret );
 356 done:
 357     mach_port_deallocate( mach_task_self(), port );
 358 #endif
 359 }
 360
 361 int send_thread_signal( struct thread *thread, int sig )
 362 {
 363     int ret = -1;
 364     mach_port_t process_port = get_process_port( thread->process );
 365
 366     if (thread->unix_pid != -1 && process_port)
 367     {
 368         mach_msg_type_name_t type;
 369         mach_port_t port;
 370
 371         if (!mach_port_extract_right( process_port, thread->unix_tid,
 372                                       MACH_MSG_TYPE_COPY_SEND, &port, &type ))
 373         {
 374             ret = syscall( SYS___pthread_kill, port, sig );
 375             mach_port_deallocate( mach_task_self(), port );
 376         }
 377         else errno = ESRCH;
 378
 379         if (ret == -1 && errno == ESRCH) /* thread got killed */
 380         {
 381             thread->unix_pid = -1;
 382             thread->unix_tid = -1;
 383         }
 384     }
 385     if (debug_level && ret != -1)
 386         fprintf( stderr, "%04x: *sent signal* signal=%d\n", thread->id, sig );
 387     return (ret != -1);
 388 }
 389
 390 /* read data from a process memory space */
 391 int read_process_memory( struct process *process, client_ptr_t ptr, data_size_t size, char *dest )
 392 {
 393     kern_return_t ret;
 394     mach_msg_type_number_t bytes_read;
 395     mach_vm_offset_t offset;
 396     vm_offset_t data;
 397     mach_vm_address_t aligned_address;
 398     mach_vm_size_t aligned_size;
 399     unsigned int page_size = get_page_size();
 400     mach_port_t process_port = get_process_port( process );
 401
 402     if (!process_port)
 403     {
 404         set_error( STATUS_ACCESS_DENIED );
 405         return 0;
 406     }
 407     if ((mach_vm_address_t)ptr != ptr)
 408     {
 409         set_error( STATUS_ACCESS_DENIED );
 410         return 0;
 411     }
 412
 413     if ((ret = task_suspend( process_port )) != KERN_SUCCESS)
 414     {
 415         mach_set_error( ret );
 416         return 0;
 417     }
 418
 419     offset = ptr % page_size;
 420     aligned_address = (mach_vm_address_t)(ptr - offset);
 421     aligned_size = (size + offset + page_size - 1) / page_size * page_size;
 422
 423     ret = mach_vm_read( process_port, aligned_address, aligned_size, &data, &bytes_read );
 424     if (ret != KERN_SUCCESS) mach_set_error( ret );
 425     else
 426     {
 427         memcpy( dest, (char *)data + offset, size );
 428         mach_vm_deallocate( mach_task_self(), data, bytes_read );
 429     }
 430     task_resume( process_port );
 431     return (ret == KERN_SUCCESS);
 432 }
 433
 434 /* write data to a process memory space */
 435 int write_process_memory( struct process *process, client_ptr_t ptr, data_size_t size, const char *src )
 436 {
 437     kern_return_t ret;
 438     mach_vm_address_t aligned_address, region_address;
 439     mach_vm_size_t aligned_size, region_size;
 440     mach_msg_type_number_t info_size, bytes_read;
 441     mach_vm_offset_t offset;
 442     vm_offset_t task_mem = 0;
 443     struct vm_region_basic_info_64 info;
 444     mach_port_t dummy;
 445     unsigned int page_size = get_page_size();
 446     mach_port_t process_port = get_process_port( process );
 447
 448     if (!process_port)
 449     {
 450         set_error( STATUS_ACCESS_DENIED );
 451         return 0;
 452     }
 453     if ((mach_vm_address_t)ptr != ptr)
 454     {
 455         set_error( STATUS_ACCESS_DENIED );
 456         return 0;
 457     }
 458
 459     offset = ptr % page_size;
 460     aligned_address = (mach_vm_address_t)(ptr - offset);
 461     aligned_size = (size + offset + page_size - 1) / page_size * page_size;
 462
 463     if ((ret = task_suspend( process_port )) != KERN_SUCCESS)
 464     {
 465         mach_set_error( ret );
 466         return 0;
 467     }
 468
 469     ret = mach_vm_read( process_port, aligned_address, aligned_size, &task_mem, &bytes_read );
 470     if (ret != KERN_SUCCESS)
 471     {
 472         mach_set_error( ret );
 473         goto failed;
 474     }
 475     region_address = aligned_address;
 476     info_size = sizeof(info);
 477     ret = mach_vm_region( process_port, &region_address, &region_size, VM_REGION_BASIC_INFO_64,
 478                      (vm_region_info_t)&info, &info_size, &dummy );
 479     if (ret != KERN_SUCCESS)
 480     {
 481         mach_set_error( ret );
 482         goto failed;
 483     }
 484     if (region_address > aligned_address ||
 485         region_address + region_size < aligned_address + aligned_size)
 486     {
 487         /* FIXME: should support multiple regions */
 488         set_error( ERROR_ACCESS_DENIED );
 489         goto failed;
 490     }
 491     ret = mach_vm_protect( process_port, aligned_address, aligned_size, 0, VM_PROT_READ | VM_PROT_WRITE );
 492     if (ret != KERN_SUCCESS)
 493     {
 494         mach_set_error( ret );
 495         goto failed;
 496     }
 497
 498     /* FIXME: there's an optimization that can be made: check first and last */
 499     /* pages for writability; read first and last pages; write interior */
 500     /* pages to task without ever reading&modifying them; if that succeeds, */
 501     /* modify first and last pages and write them. */
 502
 503     memcpy( (char*)task_mem + offset, src, size );
 504
 505     ret = mach_vm_write( process_port, aligned_address, task_mem, bytes_read );
 506     if (ret != KERN_SUCCESS) mach_set_error( ret );
 507     else
 508     {
 509         mach_vm_deallocate( mach_task_self(), task_mem, bytes_read );
 510         /* restore protection */
 511         mach_vm_protect( process_port, aligned_address, aligned_size, 0, info.protection );
 512         task_resume( process_port );
 513         return 1;
 514     }
 515
 516 failed:
 517     if (task_mem) mach_vm_deallocate( mach_task_self(), task_mem, bytes_read );
 518     task_resume( process_port );
 519     return 0;
 520 }
 521
 522 /* retrieve an LDT selector entry */
 523 void get_selector_entry( struct thread *thread, int entry, unsigned int *base,
 524                          unsigned int *limit, unsigned char *flags )
 525 {
 526     const unsigned int total_size = (2 * sizeof(int) + 1) * 8192;
 527     struct process *process = thread->process;
 528     unsigned int page_size = get_page_size();
 529     vm_offset_t data;
 530     kern_return_t ret;
 531     mach_msg_type_number_t bytes_read;
 532     mach_port_t process_port = get_process_port( thread->process );
 533
 534     if (!process->ldt_copy || !process_port)
 535     {
 536         set_error( STATUS_ACCESS_DENIED );
 537         return;
 538     }
 539     if (entry >= 8192)
 540     {
 541         set_error( STATUS_INVALID_PARAMETER );  /* FIXME */
 542         return;
 543     }
 544
 545     if ((ret = task_suspend( process_port )) == KERN_SUCCESS)
 546     {
 547         mach_vm_offset_t offset = process->ldt_copy % page_size;
 548         mach_vm_address_t aligned_address = (mach_vm_address_t)(process->ldt_copy - offset);
 549         mach_vm_size_t aligned_size = (total_size + offset + page_size - 1) / page_size * page_size;
 550
 551         ret = mach_vm_read( process_port, aligned_address, aligned_size, &data, &bytes_read );
 552         if (ret != KERN_SUCCESS) mach_set_error( ret );
 553         else
 554         {
 555             const int *ldt = (const int *)((char *)data + offset);
 556             memcpy( base, ldt + entry, sizeof(int) );
 557             memcpy( limit, ldt + entry + 8192, sizeof(int) );
 558             memcpy( flags, (char *)(ldt + 2 * 8192) + entry, 1 );
 559             mach_vm_deallocate( mach_task_self(), data, bytes_read );
 560         }
 561         task_resume( process_port );
 562     }
 563     else mach_set_error( ret );
 564 }
 565
 566 #endif  /* USE_MACH */