msdaps: Add a stub rowset proxy object.
[wine/hramrach.git] / server / ptrace.c
blob4fa48ecf17d7206ec4b3fc2e7a28649a42dffa56
1 /*
2 * Server-side ptrace support
4 * Copyright (C) 1999 Alexandre Julliard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
21 #include "config.h"
23 #include <assert.h>
24 #include <errno.h>
25 #include <stdio.h>
26 #include <signal.h>
27 #include <stdarg.h>
28 #include <sys/types.h>
29 #ifdef HAVE_SYS_PTRACE_H
30 # include <sys/ptrace.h>
31 #endif
32 #ifdef HAVE_SYS_PARAM_H
33 # include <sys/param.h>
34 #endif
35 #ifdef HAVE_SYS_WAIT_H
36 # include <sys/wait.h>
37 #endif
38 #ifdef HAVE_SYS_THR_H
39 # include <sys/ucontext.h>
40 # include <sys/thr.h>
41 #endif
42 #include <unistd.h>
44 #include "ntstatus.h"
45 #define WIN32_NO_STATUS
46 #include "winternl.h"
48 #include "file.h"
49 #include "process.h"
50 #include "thread.h"
52 #ifdef USE_PTRACE
54 #ifndef PTRACE_CONT
55 #define PTRACE_CONT PT_CONTINUE
56 #endif
57 #ifndef PTRACE_SINGLESTEP
58 #define PTRACE_SINGLESTEP PT_STEP
59 #endif
60 #ifndef PTRACE_ATTACH
61 #define PTRACE_ATTACH PT_ATTACH
62 #endif
63 #ifndef PTRACE_DETACH
64 #define PTRACE_DETACH PT_DETACH
65 #endif
66 #ifndef PTRACE_PEEKDATA
67 #define PTRACE_PEEKDATA PT_READ_D
68 #endif
69 #ifndef PTRACE_POKEDATA
70 #define PTRACE_POKEDATA PT_WRITE_D
71 #endif
72 #ifndef PTRACE_PEEKUSER
73 #define PTRACE_PEEKUSER PT_READ_U
74 #endif
75 #ifndef PTRACE_POKEUSER
76 #define PTRACE_POKEUSER PT_WRITE_U
77 #endif
79 #ifdef PT_GETDBREGS
80 #define PTRACE_GETDBREGS PT_GETDBREGS
81 #endif
82 #ifdef PT_SETDBREGS
83 #define PTRACE_SETDBREGS PT_SETDBREGS
84 #endif
86 #ifndef HAVE_SYS_PTRACE_H
87 #define PT_CONTINUE 0
88 #define PT_ATTACH 1
89 #define PT_DETACH 2
90 #define PT_READ_D 3
91 #define PT_WRITE_D 4
92 #define PT_STEP 5
93 static inline int ptrace(int req, ...) { errno = EPERM; return -1; /*FAIL*/ }
94 #endif /* HAVE_SYS_PTRACE_H */
96 /* handle a status returned by wait4 */
97 static int handle_child_status( struct thread *thread, int pid, int status, int want_sig )
99 if (WIFSTOPPED(status))
101 int sig = WSTOPSIG(status);
102 if (debug_level && thread)
103 fprintf( stderr, "%04x: *signal* signal=%d\n", thread->id, sig );
104 if (sig != want_sig)
106 /* ignore other signals for now */
107 ptrace( PTRACE_CONT, pid, (caddr_t)1, sig );
109 return sig;
111 if (thread && (WIFSIGNALED(status) || WIFEXITED(status)))
113 thread->unix_pid = -1;
114 thread->unix_tid = -1;
115 if (debug_level)
117 if (WIFSIGNALED(status))
118 fprintf( stderr, "%04x: *exited* signal=%d\n",
119 thread->id, WTERMSIG(status) );
120 else
121 fprintf( stderr, "%04x: *exited* status=%d\n",
122 thread->id, WEXITSTATUS(status) );
125 return 0;
128 /* wait4 wrapper to handle missing __WALL flag in older kernels */
129 static inline pid_t wait4_wrapper( pid_t pid, int *status, int options, struct rusage *usage )
131 #ifdef __WALL
132 static int wall_flag = __WALL;
134 for (;;)
136 pid_t ret = wait4( pid, status, options | wall_flag, usage );
137 if (ret != -1 || !wall_flag || errno != EINVAL) return ret;
138 wall_flag = 0;
140 #else
141 return wait4( pid, status, options, usage );
142 #endif
145 /* handle a SIGCHLD signal */
146 void sigchld_callback(void)
148 int pid, status;
150 for (;;)
152 if (!(pid = wait4_wrapper( -1, &status, WUNTRACED | WNOHANG, NULL ))) break;
153 if (pid != -1)
155 struct thread *thread = get_thread_from_tid( pid );
156 if (!thread) thread = get_thread_from_pid( pid );
157 handle_child_status( thread, pid, status, -1 );
159 else break;
163 /* return the Unix pid to use in ptrace calls for a given process */
164 static int get_ptrace_pid( struct thread *thread )
166 #ifdef linux /* linux always uses thread id */
167 if (thread->unix_tid != -1) return thread->unix_tid;
168 #endif
169 return thread->unix_pid;
172 /* return the Unix tid to use in ptrace calls for a given thread */
173 static int get_ptrace_tid( struct thread *thread )
175 if (thread->unix_tid != -1) return thread->unix_tid;
176 return thread->unix_pid;
179 /* wait for a ptraced child to get a certain signal */
180 static int wait4_thread( struct thread *thread, int signal )
182 int res, status;
184 start_watchdog();
185 for (;;)
187 if ((res = wait4_wrapper( get_ptrace_pid(thread), &status, WUNTRACED, NULL )) == -1)
189 if (errno == EINTR)
191 if (!watchdog_triggered()) continue;
192 if (debug_level) fprintf( stderr, "%04x: *watchdog* wait4 aborted\n", thread->id );
194 else if (errno == ECHILD) /* must have died */
196 thread->unix_pid = -1;
197 thread->unix_tid = -1;
199 else perror( "wait4" );
200 stop_watchdog();
201 return 0;
203 res = handle_child_status( thread, res, status, signal );
204 if (!res || res == signal) break;
206 stop_watchdog();
207 return (thread->unix_pid != -1);
210 /* send a signal to a specific thread */
211 static inline int tkill( int tgid, int pid, int sig )
213 #ifdef __linux__
214 int ret = -ENOSYS;
215 # ifdef __i386__
216 __asm__( "pushl %%ebx\n\t"
217 "movl %2,%%ebx\n\t"
218 "int $0x80\n\t"
219 "popl %%ebx\n\t"
220 : "=a" (ret)
221 : "0" (270) /*SYS_tgkill*/, "r" (tgid), "c" (pid), "d" (sig) );
222 if (ret == -ENOSYS)
223 __asm__( "pushl %%ebx\n\t"
224 "movl %2,%%ebx\n\t"
225 "int $0x80\n\t"
226 "popl %%ebx\n\t"
227 : "=a" (ret)
228 : "0" (238) /*SYS_tkill*/, "r" (pid), "c" (sig) );
229 # elif defined(__x86_64__)
230 __asm__( "syscall" : "=a" (ret)
231 : "0" (200) /*SYS_tkill*/, "D" (pid), "S" (sig) );
232 # endif
233 if (ret >= 0) return ret;
234 errno = -ret;
235 return -1;
236 #elif defined(__FreeBSD__) && defined(HAVE_THR_KILL2)
237 return thr_kill2( tgid, pid, sig );
238 #else
239 errno = ENOSYS;
240 return -1;
241 #endif
244 /* initialize the process tracing mechanism */
245 void init_tracing_mechanism(void)
247 /* no initialization needed for ptrace */
250 /* initialize the per-process tracing mechanism */
251 void init_process_tracing( struct process *process )
253 /* ptrace setup is done on-demand */
256 /* terminate the per-process tracing mechanism */
257 void finish_process_tracing( struct process *process )
261 /* send a Unix signal to a specific thread */
262 int send_thread_signal( struct thread *thread, int sig )
264 int ret = -1;
266 if (thread->unix_pid != -1)
268 if (thread->unix_tid != -1)
270 ret = tkill( thread->unix_pid, thread->unix_tid, sig );
271 if (ret == -1 && errno == ENOSYS) ret = kill( thread->unix_pid, sig );
273 else ret = kill( thread->unix_pid, sig );
275 if (ret == -1 && errno == ESRCH) /* thread got killed */
277 thread->unix_pid = -1;
278 thread->unix_tid = -1;
281 if (debug_level && ret != -1)
282 fprintf( stderr, "%04x: *sent signal* signal=%d\n", thread->id, sig );
283 return (ret != -1);
286 /* resume a thread after we have used ptrace on it */
287 static void resume_after_ptrace( struct thread *thread )
289 if (thread->unix_pid == -1) return;
290 if (ptrace( PTRACE_DETACH, get_ptrace_pid(thread), (caddr_t)1, 0 ) == -1)
292 if (errno == ESRCH) thread->unix_pid = thread->unix_tid = -1; /* thread got killed */
296 /* suspend a thread to allow using ptrace on it */
297 /* you must do a resume_after_ptrace when finished with the thread */
298 static int suspend_for_ptrace( struct thread *thread )
300 /* can't stop a thread while initialisation is in progress */
301 if (thread->unix_pid == -1 || !is_process_init_done(thread->process)) goto error;
303 /* this may fail if the client is already being debugged */
304 if (ptrace( PTRACE_ATTACH, get_ptrace_pid(thread), 0, 0 ) == -1)
306 if (errno == ESRCH) thread->unix_pid = thread->unix_tid = -1; /* thread got killed */
307 goto error;
309 if (wait4_thread( thread, SIGSTOP )) return 1;
310 resume_after_ptrace( thread );
311 error:
312 set_error( STATUS_ACCESS_DENIED );
313 return 0;
316 /* read a long from a thread address space */
317 static long read_thread_long( struct thread *thread, long *addr, long *data )
319 errno = 0;
320 *data = ptrace( PTRACE_PEEKDATA, get_ptrace_pid(thread), (caddr_t)addr, 0 );
321 if ( *data == -1 && errno)
323 file_set_error();
324 return -1;
326 return 0;
329 /* write a long to a thread address space */
330 static long write_thread_long( struct thread *thread, long *addr, long data, unsigned long mask )
332 long res;
333 if (mask != ~0u)
335 if (read_thread_long( thread, addr, &res ) == -1) return -1;
336 data = (data & mask) | (res & ~mask);
338 if ((res = ptrace( PTRACE_POKEDATA, get_ptrace_pid(thread), (caddr_t)addr, data )) == -1)
339 file_set_error();
340 return res;
343 /* return a thread of the process suitable for ptracing */
344 static struct thread *get_ptrace_thread( struct process *process )
346 struct thread *thread;
348 LIST_FOR_EACH_ENTRY( thread, &process->thread_list, struct thread, proc_entry )
350 if (thread->unix_pid != -1) return thread;
352 set_error( STATUS_ACCESS_DENIED ); /* process is dead */
353 return NULL;
356 /* read data from a process memory space */
357 int read_process_memory( struct process *process, client_ptr_t ptr, data_size_t size, char *dest )
359 struct thread *thread = get_ptrace_thread( process );
360 unsigned int first_offset, last_offset, len;
361 long data, *addr;
363 if (!thread) return 0;
365 if ((unsigned long)ptr != ptr)
367 set_error( STATUS_ACCESS_DENIED );
368 return 0;
371 first_offset = ptr % sizeof(long);
372 last_offset = (size + first_offset) % sizeof(long);
373 if (!last_offset) last_offset = sizeof(long);
375 addr = (long *)(unsigned long)(ptr - first_offset);
376 len = (size + first_offset + sizeof(long) - 1) / sizeof(long);
378 if (suspend_for_ptrace( thread ))
380 if (len > 1)
382 if (read_thread_long( thread, addr++, &data ) == -1) goto done;
383 memcpy( dest, (char *)&data + first_offset, sizeof(long) - first_offset );
384 dest += sizeof(long) - first_offset;
385 first_offset = 0;
386 len--;
389 while (len > 1)
391 if (read_thread_long( thread, addr++, &data ) == -1) goto done;
392 memcpy( dest, &data, sizeof(long) );
393 dest += sizeof(long);
394 len--;
397 if (read_thread_long( thread, addr++, &data ) == -1) goto done;
398 memcpy( dest, (char *)&data + first_offset, last_offset - first_offset );
399 len--;
401 done:
402 resume_after_ptrace( thread );
404 return !len;
407 /* make sure we can write to the whole address range */
408 /* len is the total size (in ints) */
409 static int check_process_write_access( struct thread *thread, long *addr, data_size_t len )
411 int page = get_page_size() / sizeof(int);
413 for (;;)
415 if (write_thread_long( thread, addr, 0, 0 ) == -1) return 0;
416 if (len <= page) break;
417 addr += page;
418 len -= page;
420 return (write_thread_long( thread, addr + len - 1, 0, 0 ) != -1);
423 /* write data to a process memory space */
424 int write_process_memory( struct process *process, client_ptr_t ptr, data_size_t size, const char *src )
426 struct thread *thread = get_ptrace_thread( process );
427 int ret = 0;
428 long data = 0;
429 data_size_t len;
430 long *addr;
431 unsigned long first_mask, first_offset, last_mask, last_offset;
433 if (!thread) return 0;
435 if ((unsigned long)ptr != ptr)
437 set_error( STATUS_ACCESS_DENIED );
438 return 0;
441 /* compute the mask for the first long */
442 first_mask = ~0;
443 first_offset = ptr % sizeof(long);
444 memset( &first_mask, 0, first_offset );
446 /* compute the mask for the last long */
447 last_offset = (size + first_offset) % sizeof(long);
448 if (!last_offset) last_offset = sizeof(long);
449 last_mask = 0;
450 memset( &last_mask, 0xff, last_offset );
452 addr = (long *)(unsigned long)(ptr - first_offset);
453 len = (size + first_offset + sizeof(long) - 1) / sizeof(long);
455 if (suspend_for_ptrace( thread ))
457 if (!check_process_write_access( thread, addr, len ))
459 set_error( STATUS_ACCESS_DENIED );
460 goto done;
462 /* first word is special */
463 if (len > 1)
465 memcpy( (char *)&data + first_offset, src, sizeof(long) - first_offset );
466 src += sizeof(long) - first_offset;
467 if (write_thread_long( thread, addr++, data, first_mask ) == -1) goto done;
468 first_offset = 0;
469 len--;
471 else last_mask &= first_mask;
473 while (len > 1)
475 memcpy( &data, src, sizeof(long) );
476 src += sizeof(long);
477 if (write_thread_long( thread, addr++, data, ~0ul ) == -1) goto done;
478 len--;
481 /* last word is special too */
482 memcpy( (char *)&data + first_offset, src, last_offset - first_offset );
483 if (write_thread_long( thread, addr, data, last_mask ) == -1) goto done;
484 ret = 1;
486 done:
487 resume_after_ptrace( thread );
489 return ret;
492 /* retrieve an LDT selector entry */
493 void get_selector_entry( struct thread *thread, int entry, unsigned int *base,
494 unsigned int *limit, unsigned char *flags )
496 if (!thread->process->ldt_copy)
498 set_error( STATUS_ACCESS_DENIED );
499 return;
501 if (entry >= 8192)
503 set_error( STATUS_ACCESS_VIOLATION );
504 return;
506 if (suspend_for_ptrace( thread ))
508 unsigned char flags_buf[sizeof(long)];
509 long *addr = (long *)(unsigned long)thread->process->ldt_copy + entry;
510 if (read_thread_long( thread, addr, (long *)base ) == -1) goto done;
511 if (read_thread_long( thread, addr + 8192, (long *)limit ) == -1) goto done;
512 addr = (long *)(unsigned long)thread->process->ldt_copy + 2*8192 + (entry / sizeof(long));
513 if (read_thread_long( thread, addr, (long *)flags_buf ) == -1) goto done;
514 *flags = flags_buf[entry % sizeof(long)];
515 done:
516 resume_after_ptrace( thread );
521 #if defined(linux) && (defined(__i386__) || defined(__x86_64__))
523 #ifdef HAVE_SYS_USER_H
524 # include <sys/user.h>
525 #endif
527 /* debug register offset in struct user */
528 #define DR_OFFSET(dr) ((((struct user *)0)->u_debugreg) + (dr))
530 /* retrieve the thread x86 registers */
531 void get_thread_context( struct thread *thread, context_t *context, unsigned int flags )
533 int i, pid = get_ptrace_tid(thread);
534 long data[8];
536 /* all other regs are handled on the client side */
537 assert( flags == SERVER_CTX_DEBUG_REGISTERS );
539 if (!suspend_for_ptrace( thread )) return;
541 for (i = 0; i < 8; i++)
543 if (i == 4 || i == 5) continue;
544 errno = 0;
545 data[i] = ptrace( PTRACE_PEEKUSER, pid, DR_OFFSET(i), 0 );
546 if ((data[i] == -1) && errno)
548 file_set_error();
549 goto done;
552 context->debug.i386_regs.dr0 = data[0];
553 context->debug.i386_regs.dr1 = data[1];
554 context->debug.i386_regs.dr2 = data[2];
555 context->debug.i386_regs.dr3 = data[3];
556 context->debug.i386_regs.dr6 = data[6];
557 context->debug.i386_regs.dr7 = data[7];
558 context->flags |= SERVER_CTX_DEBUG_REGISTERS;
559 done:
560 resume_after_ptrace( thread );
563 /* set the thread x86 registers */
564 void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
566 int pid = get_ptrace_tid( thread );
568 /* all other regs are handled on the client side */
569 assert( flags == SERVER_CTX_DEBUG_REGISTERS );
571 if (!suspend_for_ptrace( thread )) return;
573 if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(0), context->debug.i386_regs.dr0 ) == -1) goto error;
574 if (thread->context) thread->context->debug.i386_regs.dr0 = context->debug.i386_regs.dr0;
575 if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(1), context->debug.i386_regs.dr1 ) == -1) goto error;
576 if (thread->context) thread->context->debug.i386_regs.dr1 = context->debug.i386_regs.dr1;
577 if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(2), context->debug.i386_regs.dr2 ) == -1) goto error;
578 if (thread->context) thread->context->debug.i386_regs.dr2 = context->debug.i386_regs.dr2;
579 if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(3), context->debug.i386_regs.dr3 ) == -1) goto error;
580 if (thread->context) thread->context->debug.i386_regs.dr3 = context->debug.i386_regs.dr3;
581 if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(6), context->debug.i386_regs.dr6 ) == -1) goto error;
582 if (thread->context) thread->context->debug.i386_regs.dr6 = context->debug.i386_regs.dr6;
583 if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.i386_regs.dr7 ) == -1) goto error;
584 if (thread->context) thread->context->debug.i386_regs.dr7 = context->debug.i386_regs.dr7;
585 resume_after_ptrace( thread );
586 return;
587 error:
588 file_set_error();
589 resume_after_ptrace( thread );
592 #elif defined(__i386__) && defined(PTRACE_GETDBREGS) && defined(PTRACE_SETDBREGS) && \
593 (defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__) || defined(__NetBSD__))
595 #include <machine/reg.h>
597 /* retrieve the thread x86 registers */
598 void get_thread_context( struct thread *thread, context_t *context, unsigned int flags )
600 int pid = get_ptrace_tid(thread);
601 struct dbreg dbregs;
603 /* all other regs are handled on the client side */
604 assert( flags == SERVER_CTX_DEBUG_REGISTERS );
606 if (!suspend_for_ptrace( thread )) return;
608 if (ptrace( PTRACE_GETDBREGS, pid, (caddr_t) &dbregs, 0 ) == -1) file_set_error();
609 else
611 #ifdef DBREG_DRX
612 /* needed for FreeBSD, the structure fields have changed under 5.x */
613 context->debug.i386_regs.dr0 = DBREG_DRX((&dbregs), 0);
614 context->debug.i386_regs.dr1 = DBREG_DRX((&dbregs), 1);
615 context->debug.i386_regs.dr2 = DBREG_DRX((&dbregs), 2);
616 context->debug.i386_regs.dr3 = DBREG_DRX((&dbregs), 3);
617 context->debug.i386_regs.dr6 = DBREG_DRX((&dbregs), 6);
618 context->debug.i386_regs.dr7 = DBREG_DRX((&dbregs), 7);
619 #else
620 context->debug.i386_regs.dr0 = dbregs.dr0;
621 context->debug.i386_regs.dr1 = dbregs.dr1;
622 context->debug.i386_regs.dr2 = dbregs.dr2;
623 context->debug.i386_regs.dr3 = dbregs.dr3;
624 context->debug.i386_regs.dr6 = dbregs.dr6;
625 context->debug.i386_regs.dr7 = dbregs.dr7;
626 #endif
627 context->flags |= SERVER_CTX_DEBUG_REGISTERS;
629 resume_after_ptrace( thread );
632 /* set the thread x86 registers */
633 void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
635 int pid = get_ptrace_tid(thread);
636 struct dbreg dbregs;
638 /* all other regs are handled on the client side */
639 assert( flags == SERVER_CTX_DEBUG_REGISTERS );
641 if (!suspend_for_ptrace( thread )) return;
643 #ifdef DBREG_DRX
644 /* needed for FreeBSD, the structure fields have changed under 5.x */
645 DBREG_DRX((&dbregs), 0) = context->debug.i386_regs.dr0;
646 DBREG_DRX((&dbregs), 1) = context->debug.i386_regs.dr1;
647 DBREG_DRX((&dbregs), 2) = context->debug.i386_regs.dr2;
648 DBREG_DRX((&dbregs), 3) = context->debug.i386_regs.dr3;
649 DBREG_DRX((&dbregs), 4) = 0;
650 DBREG_DRX((&dbregs), 5) = 0;
651 DBREG_DRX((&dbregs), 6) = context->debug.i386_regs.dr6;
652 DBREG_DRX((&dbregs), 7) = context->debug.i386_regs.dr7;
653 #else
654 dbregs.dr0 = context->debug.i386_regs.dr0;
655 dbregs.dr1 = context->debug.i386_regs.dr1;
656 dbregs.dr2 = context->debug.i386_regs.dr2;
657 dbregs.dr3 = context->debug.i386_regs.dr3;
658 dbregs.dr4 = 0;
659 dbregs.dr5 = 0;
660 dbregs.dr6 = context->debug.i386_regs.dr6;
661 dbregs.dr7 = context->debug.i386_regs.dr7;
662 #endif
663 if (ptrace( PTRACE_SETDBREGS, pid, (caddr_t) &dbregs, 0 ) == -1) file_set_error();
664 else if (thread->context)
665 thread->context->debug.i386_regs = context->debug.i386_regs; /* update the cached values */
666 resume_after_ptrace( thread );
669 #else /* linux || __FreeBSD__ */
671 /* retrieve the thread x86 registers */
672 void get_thread_context( struct thread *thread, context_t *context, unsigned int flags )
676 /* set the thread x86 debug registers */
677 void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
681 #endif /* linux || __FreeBSD__ */
683 #endif /* USE_PTRACE */