hurd/hurdinit.c

   1 /* Copyright (C) 1992-2018 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, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/stat.h>
  19 #include <stdlib.h>
  20 #include <stdio.h>
  21 #include <unistd.h>
  22 #include <hurd.h>
  23 #include <hurd/port.h>
  24 #include "set-hooks.h"
  25 #include "hurdmalloc.h"         /* XXX */
  26
  27
  28 int _hurd_exec_flags;
  29 struct hurd_port *_hurd_ports;
  30 unsigned int _hurd_nports;
  31 mode_t _hurd_umask;
  32 sigset_t _hurdsig_traced;
  33
  34 char **__libc_argv;
  35 int __libc_argc;
  36
  37
  38 error_t
  39 _hurd_ports_use (int which, error_t (*operate) (mach_port_t))
  40 {
  41   if (__glibc_unlikely (_hurd_ports == NULL))
  42     /* This means that _hurd_init has not been called yet, which is
  43        normally only the case in the bootstrap filesystem, and there
  44        only in the early phases of booting.  */
  45     return EGRATUITOUS;
  46
  47   return HURD_PORT_USE (&_hurd_ports[which], (*operate) (port));
  48 }
  49
  50 DEFINE_HOOK (_hurd_subinit, (void));
  51
  52 __typeof (_hurd_proc_init) _hurd_new_proc_init; /* below */
  53
  54 /* Initialize the library data structures from the
  55    ints and ports passed to us by the exec server.
  56
  57    PORTARRAY and INTARRAY are vm_deallocate'd.  */
  58
  59 void
  60 _hurd_init (int flags, char **argv,
  61             mach_port_t *portarray, size_t portarraysize,
  62             int *intarray, size_t intarraysize)
  63 {
  64   size_t i;
  65
  66   _hurd_exec_flags = flags;
  67
  68   _hurd_ports = malloc (portarraysize * sizeof (*_hurd_ports));
  69   if (_hurd_ports == NULL)
  70     __libc_fatal ("Can't allocate _hurd_ports\n");
  71   _hurd_nports = portarraysize;
  72
  73   /* See what ports we were passed.  */
  74   for (i = 0; i < portarraysize; ++i)
  75     _hurd_port_init (&_hurd_ports[i], portarray[i]);
  76
  77   /* When the user asks for the bootstrap port,
  78      he will get the one the exec server passed us.  */
  79   __task_set_special_port (__mach_task_self (), TASK_BOOTSTRAP_PORT,
  80                            portarray[INIT_PORT_BOOTSTRAP]);
  81
  82   if (intarraysize > INIT_UMASK)
  83     _hurd_umask = intarray[INIT_UMASK] & 0777;
  84   else
  85     _hurd_umask = CMASK;
  86
  87   if (intarraysize > INIT_TRACEMASK)
  88     _hurdsig_traced = intarray[INIT_TRACEMASK];
  89
  90   /* Tell the proc server we exist, if it does.  */
  91   if (portarray[INIT_PORT_PROC] != MACH_PORT_NULL)
  92     _hurd_new_proc_init (argv, intarray, intarraysize);
  93
  94   /* All done with init ints and ports.  */
  95   __vm_deallocate (__mach_task_self (),
  96                    (vm_address_t) intarray,
  97                    intarraysize * sizeof (int));
  98   __vm_deallocate (__mach_task_self (),
  99                    (vm_address_t) portarray,
 100                    portarraysize * sizeof (mach_port_t));
 101
 102   if (flags & EXEC_SECURE)
 103     /* XXX if secure exec, elide environment variables
 104        which the library uses and could be security holes.
 105        CORESERVER, COREFILE
 106        */ ;
 107
 108   /* Call other things which want to do some initialization.  These are not
 109      on the __libc_subinit hook because things there like to be able to
 110      assume the availability of the POSIX.1 services we provide.  */
 111   RUN_HOOK (_hurd_subinit, ());
 112 }
 113 libc_hidden_def (_hurd_init)
 114 \f
 115 #include <hurd/signal.h>
 116
 117 /* The user can do "int _hide_arguments = 1;" to make
 118    sure the arguments are never visible with `ps'.  */
 119 int _hide_arguments, _hide_environment;
 120
 121 /* Hook for things which should be initialized as soon as the proc
 122    server is available.  */
 123 DEFINE_HOOK (_hurd_proc_subinit, (void));
 124
 125 /* Do startup handshaking with the proc server just installed in _hurd_ports.
 126    Call _hurdsig_init to set up signal processing.  */
 127
 128 void
 129 _hurd_new_proc_init (char **argv,
 130                      const int *intarray, size_t intarraysize)
 131 {
 132   mach_port_t oldmsg;
 133   struct hurd_userlink ulink;
 134   process_t procserver;
 135
 136   /* Initialize the signal code; Mach exceptions will become signals.  */
 137   _hurdsig_init (intarray, intarraysize);
 138
 139   /* The signal thread is now prepared to receive messages.
 140      It is safe to give the port to the proc server.  */
 141
 142   procserver = _hurd_port_get (&_hurd_ports[INIT_PORT_PROC], &ulink);
 143
 144   /* Give the proc server our message port.  */
 145   __proc_setmsgport (procserver, _hurd_msgport, &oldmsg);
 146   if (oldmsg != MACH_PORT_NULL)
 147     /* Deallocate the old msg port we replaced.  */
 148     __mach_port_deallocate (__mach_task_self (), oldmsg);
 149
 150   /* Tell the proc server where our args and environment are.  */
 151   __proc_set_arg_locations (procserver,
 152                             _hide_arguments ? 0 : (vm_address_t) argv,
 153                             _hide_environment ? 0 : (vm_address_t) __environ);
 154
 155   _hurd_port_free (&_hurd_ports[INIT_PORT_PROC], &ulink, procserver);
 156
 157   /* Initialize proc server-assisted fault recovery for the signal thread.  */
 158   _hurdsig_fault_init ();
 159
 160   /* Call other things which want to do some initialization.  These are not
 161      on the _hurd_subinit hook because things there assume that things done
 162      here, like _hurd_pid, are already initialized.  */
 163   RUN_HOOK (_hurd_proc_subinit, ());
 164
 165   /* XXX This code should probably be removed entirely at some point.  This
 166      conditional should make it reasonably usable with old gdb's for a
 167      while.  Eventually it probably makes most sense for the exec server to
 168      mask out EXEC_SIGTRAP so the debugged program is closer to not being
 169      able to tell it's being debugged.  */
 170   if (!__sigisemptyset (&_hurdsig_traced)
 171 #ifdef EXEC_SIGTRAP
 172       && !(_hurd_exec_flags & EXEC_SIGTRAP)
 173 #endif
 174       )
 175     /* This process is "traced", meaning it should stop on signals or exec.
 176        We are all set up now to handle signals.  Stop ourselves, to inform
 177        our parent (presumably a debugger) that the exec has completed.  */
 178     __msg_sig_post (_hurd_msgport, SIGTRAP, 0, __mach_task_self ());
 179 }
 180
 181 #include <shlib-compat.h>
 182 versioned_symbol (libc, _hurd_new_proc_init, _hurd_proc_init, GLIBC_2_1);
 183 \f
 184 /* Called when we get a message telling us to change our proc server port.  */
 185
 186 error_t
 187 _hurd_setproc (process_t procserver)
 188 {
 189   error_t err;
 190   mach_port_t oldmsg;
 191
 192   /* Give the proc server our message port.  */
 193   if (err = __proc_setmsgport (procserver, _hurd_msgport, &oldmsg))
 194     return err;
 195   if (oldmsg != MACH_PORT_NULL)
 196     /* Deallocate the old msg port we replaced.  */
 197     __mach_port_deallocate (__mach_task_self (), oldmsg);
 198
 199   /* Tell the proc server where our args and environment are.  */
 200   if (err = __proc_set_arg_locations (procserver,
 201                                       _hide_arguments ? 0 :
 202                                       (vm_address_t) __libc_argv,
 203                                       _hide_environment ? 0 :
 204                                       (vm_address_t) __environ))
 205     return err;
 206
 207   /* Those calls worked, so the port looks good.  */
 208   _hurd_port_set (&_hurd_ports[INIT_PORT_PROC], procserver);
 209
 210   {
 211     pid_t oldpgrp = _hurd_pgrp;
 212
 213     /* Call these functions again so they can fetch the
 214        new information from the new proc server.  */
 215     RUN_HOOK (_hurd_proc_subinit, ());
 216
 217     if (_hurd_pgrp != oldpgrp)
 218       {
 219         /* Run things that want notification of a pgrp change.  */
 220         DECLARE_HOOK (_hurd_pgrp_changed_hook, (pid_t));
 221         RUN_HOOK (_hurd_pgrp_changed_hook, (_hurd_pgrp));
 222       }
 223   }
 224
 225   return 0;
 226 }