hurd/hurdinit.c

   1 /* Copyright (C) 1992-2022 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    <https://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 <ldsodefs.h>
  25 #include "set-hooks.h"
  26 #include "hurdmalloc.h"         /* XXX */
  27
  28
  29 int _hurd_exec_flags;
  30 struct hurd_port *_hurd_ports;
  31 unsigned int _hurd_nports;
  32 mode_t _hurd_umask;
  33 sigset_t _hurdsig_traced;
  34
  35 char **__libc_argv;
  36 int __libc_argc;
  37
  38 static int *_hurd_intarray;
  39 static size_t _hurd_intarraysize;
  40 static mach_port_t *_hurd_portarray;
  41 static size_t _hurd_portarraysize;
  42
  43 error_t
  44 _hurd_ports_use (int which, error_t (*operate) (mach_port_t))
  45 {
  46   if (__glibc_unlikely (_hurd_ports == NULL))
  47     /* This means that _hurd_init has not been called yet, which is
  48        normally only the case in the bootstrap filesystem, and there
  49        only in the early phases of booting.  */
  50     return EGRATUITOUS;
  51
  52   return HURD_PORT_USE (&_hurd_ports[which], (*operate) (port));
  53 }
  54
  55 DEFINE_HOOK (_hurd_subinit, (void));
  56
  57 __typeof (_hurd_proc_init) _hurd_new_proc_init; /* below */
  58
  59 /* Initialize the library data structures from the
  60    ints and ports passed to us by the exec server.
  61
  62    PORTARRAY and INTARRAY are vm_deallocate'd.  */
  63
  64 void
  65 _hurd_init (int flags, char **argv,
  66             mach_port_t *portarray, size_t portarraysize,
  67             int *intarray, size_t intarraysize)
  68 {
  69   size_t i;
  70
  71   _hurd_exec_flags = flags;
  72
  73   _hurd_ports = malloc (portarraysize * sizeof (*_hurd_ports));
  74   if (_hurd_ports == NULL)
  75     __libc_fatal ("Can't allocate _hurd_ports\n");
  76   _hurd_nports = portarraysize;
  77
  78   /* See what ports we were passed.  */
  79   for (i = 0; i < portarraysize; ++i)
  80     _hurd_port_init (&_hurd_ports[i], portarray[i]);
  81
  82   /* When the user asks for the bootstrap port,
  83      he will get the one the exec server passed us.  */
  84   __task_set_special_port (__mach_task_self (), TASK_BOOTSTRAP_PORT,
  85                            portarray[INIT_PORT_BOOTSTRAP]);
  86
  87   if (intarraysize > INIT_UMASK)
  88     _hurd_umask = intarray[INIT_UMASK] & 0777;
  89   else
  90     _hurd_umask = CMASK;
  91
  92   if (intarraysize > INIT_TRACEMASK)
  93     _hurdsig_traced = intarray[INIT_TRACEMASK];
  94
  95   _hurd_intarray = intarray;
  96   _hurd_intarraysize = intarraysize;
  97   _hurd_portarray = portarray;
  98   _hurd_portarraysize = portarraysize;
  99
 100   if (flags & EXEC_SECURE)
 101     {
 102       /* XXX if secure exec, elide environment variables
 103          which the library uses and could be security holes.
 104          CORESERVER, COREFILE
 105       */
 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_RELHOOK (_hurd_subinit, ());
 112 }
 113 libc_hidden_def (_hurd_init)
 114
 115 void
 116 _hurd_libc_proc_init (char **argv)
 117 {
 118   if (_hurd_portarray)
 119     {
 120       /* We will start the signal thread, so we need to initialize libpthread
 121        * if linked in.  */
 122       if (__pthread_initialize_minimal != NULL)
 123         __pthread_initialize_minimal ();
 124
 125       /* Tell the proc server we exist, if it does.  */
 126       if (_hurd_portarray[INIT_PORT_PROC] != MACH_PORT_NULL)
 127         _hurd_new_proc_init (argv, _hurd_intarray, _hurd_intarraysize);
 128
 129       /* All done with init ints and ports.  */
 130       __vm_deallocate (__mach_task_self (),
 131                        (vm_address_t) _hurd_intarray,
 132                        _hurd_intarraysize * sizeof (int));
 133       _hurd_intarray = NULL;
 134       _hurd_intarraysize = 0;
 135
 136       __vm_deallocate (__mach_task_self (),
 137                        (vm_address_t) _hurd_portarray,
 138                        _hurd_portarraysize * sizeof (mach_port_t));
 139       _hurd_portarray = NULL;
 140       _hurd_portarraysize = 0;
 141     }
 142 }
 143 libc_hidden_def (_hurd_libc_proc_init)
 144 \f
 145 #include <hurd/signal.h>
 146
 147 /* The user can do "int _hide_arguments = 1;" to make
 148    sure the arguments are never visible with `ps'.  */
 149 int _hide_arguments, _hide_environment;
 150
 151 /* Hook for things which should be initialized as soon as the proc
 152    server is available.  */
 153 DEFINE_HOOK (_hurd_proc_subinit, (void));
 154
 155 /* Do startup handshaking with the proc server just installed in _hurd_ports.
 156    Call _hurdsig_init to set up signal processing.  */
 157
 158 void
 159 _hurd_new_proc_init (char **argv,
 160                      const int *intarray, size_t intarraysize)
 161 {
 162   mach_port_t oldmsg;
 163   struct hurd_userlink ulink;
 164   process_t procserver;
 165
 166   /* Initialize the signal code; Mach exceptions will become signals.  */
 167   _hurdsig_init (intarray, intarraysize);
 168
 169   /* The signal thread is now prepared to receive messages.
 170      It is safe to give the port to the proc server.  */
 171
 172   procserver = _hurd_port_get (&_hurd_ports[INIT_PORT_PROC], &ulink);
 173
 174   /* Give the proc server our message port.  */
 175   __proc_setmsgport (procserver, _hurd_msgport, &oldmsg);
 176   if (oldmsg != MACH_PORT_NULL)
 177     /* Deallocate the old msg port we replaced.  */
 178     __mach_port_deallocate (__mach_task_self (), oldmsg);
 179
 180   /* Tell the proc server where our args and environment are.  */
 181   __proc_set_arg_locations (procserver,
 182                             _hide_arguments ? 0 : (vm_address_t) argv,
 183                             _hide_environment ? 0 : (vm_address_t) __environ);
 184
 185   _hurd_port_free (&_hurd_ports[INIT_PORT_PROC], &ulink, procserver);
 186
 187   /* Initialize proc server-assisted fault recovery for the signal thread.  */
 188   _hurdsig_fault_init ();
 189
 190   /* Call other things which want to do some initialization.  These are not
 191      on the _hurd_subinit hook because things there assume that things done
 192      here, like _hurd_pid, are already initialized.  */
 193   RUN_RELHOOK (_hurd_proc_subinit, ());
 194
 195   /* XXX This code should probably be removed entirely at some point.  This
 196      conditional should make it reasonably usable with old gdb's for a
 197      while.  Eventually it probably makes most sense for the exec server to
 198      mask out EXEC_SIGTRAP so the debugged program is closer to not being
 199      able to tell it's being debugged.  */
 200   if (!__sigisemptyset (&_hurdsig_traced)
 201 #ifdef EXEC_SIGTRAP
 202       && !(_hurd_exec_flags & EXEC_SIGTRAP)
 203 #endif
 204       )
 205     /* This process is "traced", meaning it should stop on signals or exec.
 206        We are all set up now to handle signals.  Stop ourselves, to inform
 207        our parent (presumably a debugger) that the exec has completed.  */
 208     __msg_sig_post (_hurd_msgport, SIGTRAP, TRAP_TRACE, __mach_task_self ());
 209 }
 210
 211 #include <shlib-compat.h>
 212 versioned_symbol (libc, _hurd_new_proc_init, _hurd_proc_init, GLIBC_2_1);
 213 \f
 214 /* Called when we get a message telling us to change our proc server port.  */
 215
 216 error_t
 217 _hurd_setproc (process_t procserver)
 218 {
 219   error_t err;
 220   mach_port_t oldmsg;
 221
 222   /* Give the proc server our message port.  */
 223   if (err = __proc_setmsgport (procserver, _hurd_msgport, &oldmsg))
 224     return err;
 225   if (oldmsg != MACH_PORT_NULL)
 226     /* Deallocate the old msg port we replaced.  */
 227     __mach_port_deallocate (__mach_task_self (), oldmsg);
 228
 229   /* Tell the proc server where our args and environment are.  */
 230   if (err = __proc_set_arg_locations (procserver,
 231                                       _hide_arguments ? 0
 232                                       : (vm_address_t) __libc_argv,
 233                                       _hide_environment ? 0
 234                                       : (vm_address_t) __environ))
 235     return err;
 236
 237   /* Those calls worked, so the port looks good.  */
 238   _hurd_port_set (&_hurd_ports[INIT_PORT_PROC], procserver);
 239
 240   {
 241     pid_t oldpgrp = _hurd_pgrp;
 242
 243     /* Call these functions again so they can fetch the
 244        new information from the new proc server.  */
 245     RUN_RELHOOK (_hurd_proc_subinit, ());
 246
 247     if (_hurd_pgrp != oldpgrp)
 248       {
 249         /* Run things that want notification of a pgrp change.  */
 250         DECLARE_HOOK (_hurd_pgrp_changed_hook, (pid_t));
 251         RUN_HOOK (_hurd_pgrp_changed_hook, (_hurd_pgrp));
 252       }
 253   }
 254
 255   return 0;
 256 }