sysdeps/unix/sysv/linux/ptrace.c

   1 /* Copyright (C) 1995, 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <sys/types.h>
  21 #include <sys/ptrace.h>
  22 #include <sys/user.h>
  23 #include <stdarg.h>
  24
  25 #include <sysdep.h>
  26 #include <sys/syscall.h>
  27 #include <bp-checks.h>
  28
  29 extern long int __syscall_ptrace (int, pid_t, void *__unbounded,
  30                                   void *__unbounded);
  31
  32 long int
  33 ptrace (enum __ptrace_request request, ...)
  34 {
  35   long int res, ret;
  36   va_list ap;
  37   pid_t pid;
  38   void *addr, *data;
  39
  40   va_start (ap, request);
  41   pid = va_arg (ap, pid_t);
  42   addr = va_arg (ap, void *);
  43   data = va_arg (ap, void *);
  44   va_end (ap);
  45
  46   if (request > 0 && request < 4)
  47     data = &ret;
  48
  49 #if __BOUNDED_POINTERS__
  50   switch (request)
  51     {
  52     case PTRACE_PEEKTEXT:
  53     case PTRACE_PEEKDATA:
  54     case PTRACE_PEEKUSER:
  55     case PTRACE_POKETEXT:
  56     case PTRACE_POKEDATA:
  57     case PTRACE_POKEUSER:
  58       (void) CHECK_1 ((int *) addr);
  59       (void) CHECK_1 ((int *) data);
  60       break;
  61
  62     case PTRACE_GETREGS:
  63     case PTRACE_SETREGS:
  64 #ifdef __i386__
  65       (void) CHECK_1 ((struct user_regs_struct *) data);
  66 #else
  67       /* We don't know the size of data, so the best we can do is ensure
  68          that `data' is valid for at least one word.  */
  69       (void) CHECK_1 ((int *) data);
  70 #endif
  71       break;
  72
  73     case PTRACE_GETFPREGS:
  74     case PTRACE_SETFPREGS:
  75 #ifdef __i386__
  76       (void) CHECK_1 ((struct user_fpregs_struct *) data);
  77 #else
  78       /* We don't know the size of data, so the best we can do is ensure
  79          that `data' is valid for at least one word.  */
  80       (void) CHECK_1 ((int *) data);
  81 #endif
  82       break;
  83
  84     case PTRACE_GETFPXREGS:
  85     case PTRACE_SETFPXREGS:
  86 #ifdef __i386__
  87       (void) CHECK_1 ((struct user_fpxregs_struct *) data);
  88 #else
  89       /* We don't know the size of data, so the best we can do is ensure
  90          that `data' is valid for at least one word.  */
  91       (void) CHECK_1 ((int *) data);
  92 #endif
  93       break;
  94
  95     case PTRACE_TRACEME:
  96     case PTRACE_CONT:
  97     case PTRACE_KILL:
  98     case PTRACE_SINGLESTEP:
  99     case PTRACE_ATTACH:
 100     case PTRACE_DETACH:
 101     case PTRACE_SYSCALL:
 102       /* Neither `data' nor `addr' needs any checks.  */
 103       break;
 104     };
 105 #endif
 106
 107   res = INLINE_SYSCALL (ptrace, 4, request, pid,
 108                         __ptrvalue (addr), __ptrvalue (data));
 109   if (res >= 0 && request > 0 && request < 4)
 110     {
 111       __set_errno (0);
 112       return ret;
 113     }
 114
 115   return res;
 116 }