hurd/hurdmsg.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 <hurd.h>
  19 #include <hurd/msg_server.h>
  20 #include <hurd/fd.h>
  21 #include <unistd.h>
  22 #include <limits.h>
  23 #include <string.h>
  24 #include <argz.h>
  25
  26
  27 #define AUTHCHECK \
  28   if (auth != mach_task_self () && ! __USEPORT (AUTH, port == auth)) \
  29     return EPERM
  30
  31
  32 /* Snarfing and frobbing the init ports.  */
  33
  34 kern_return_t
  35   _S_msg_get_init_port (mach_port_t msgport, mach_port_t auth, int which,
  36                         mach_port_t *result, mach_msg_type_name_t *result_type)
  37 {
  38   AUTHCHECK;
  39   *result_type = MACH_MSG_TYPE_MOVE_SEND;
  40   /* This function adds a new user reference for the *RESULT it gives back.
  41      Our reply message uses a move-send right that consumes this reference.  */
  42   return _hurd_ports_get (which, result);
  43 }
  44
  45 kern_return_t
  46 _S_msg_set_init_port (mach_port_t msgport, mach_port_t auth,
  47                       int which, mach_port_t port)
  48 {
  49   error_t err;
  50
  51   AUTHCHECK;
  52
  53   err = _hurd_ports_set (which, port);
  54   if (err == 0)
  55     __mach_port_deallocate (__mach_task_self (), port);
  56
  57   return 0;
  58 }
  59
  60 kern_return_t
  61 _S_msg_get_init_ports (mach_port_t msgport, mach_port_t auth,
  62                        mach_port_t **ports,
  63                        mach_msg_type_name_t *ports_type,
  64                        mach_msg_type_number_t *nports)
  65 {
  66   mach_msg_type_number_t i;
  67   error_t err;
  68
  69   AUTHCHECK;
  70
  71   if (err = __vm_allocate (__mach_task_self (), (vm_address_t *) ports,
  72                            _hurd_nports * sizeof (mach_port_t), 1))
  73     return err;
  74   *nports = _hurd_nports;
  75
  76   for (i = 0; i < _hurd_nports; ++i)
  77     /* This function adds a new user ref for the *RESULT it gives back.
  78        Our reply message uses move-send rights that consumes this ref.  */
  79     if (err = _hurd_ports_get (i, &(*ports)[i]))
  80       {
  81         /* Died part way through.  Deallocate the ports already fetched.  */
  82         while (i-- > 0)
  83           __mach_port_deallocate (__mach_task_self (), (*ports)[i]);
  84         __vm_deallocate (__mach_task_self (),
  85                          (vm_address_t) *ports,
  86                          *nports * sizeof (mach_port_t));
  87         return err;
  88       }
  89
  90   *ports_type = MACH_MSG_TYPE_MOVE_SEND;
  91   return 0;
  92 }
  93
  94 kern_return_t
  95 _S_msg_set_init_ports (mach_port_t msgport, mach_port_t auth,
  96                        const mach_port_t *ports, mach_msg_type_number_t nports)
  97 {
  98   mach_msg_type_number_t i;
  99   error_t err;
 100
 101   AUTHCHECK;
 102
 103   for (i = 0; i < _hurd_nports; ++i)
 104     {
 105       if (err = _hurd_ports_set (i, ports[i]))
 106         return err;
 107       else
 108         __mach_port_deallocate (__mach_task_self (), ports[i]);
 109     }
 110
 111   return 0;
 112 }
 113 \f
 114 /* Snarfing and frobbing the init ints.  */
 115
 116 static kern_return_t
 117 get_int (int which, int *value)
 118 {
 119   switch (which)
 120     {
 121     case INIT_UMASK:
 122       *value = _hurd_umask;
 123       return 0;
 124     case INIT_SIGPENDING:
 125       {
 126         struct hurd_sigstate *ss = _hurd_global_sigstate;
 127         __spin_lock (&ss->lock);
 128         *value = ss->pending;
 129         __spin_unlock (&ss->lock);
 130         return 0;
 131       }
 132     case INIT_SIGIGN:
 133       {
 134         struct hurd_sigstate *ss = _hurd_global_sigstate;
 135         sigset_t ign;
 136         int sig;
 137         __spin_lock (&ss->lock);
 138         __sigemptyset (&ign);
 139         for (sig = 1; sig < NSIG; ++sig)
 140           if (ss->actions[sig].sa_handler == SIG_IGN)
 141             __sigaddset (&ign, sig);
 142         __spin_unlock (&ss->lock);
 143         *value = ign;
 144         return 0;
 145       }
 146     default:
 147       return EINVAL;
 148     }
 149 }
 150
 151 kern_return_t
 152 _S_msg_get_init_int (mach_port_t msgport, mach_port_t auth,
 153                      int which, int *value)
 154 {
 155   AUTHCHECK;
 156
 157   return get_int (which, value);
 158 }
 159
 160 kern_return_t
 161 _S_msg_get_init_ints (mach_port_t msgport, mach_port_t auth,
 162                       int **values, mach_msg_type_number_t *nvalues)
 163 {
 164   error_t err;
 165   mach_msg_type_number_t i;
 166
 167   AUTHCHECK;
 168
 169   if (err = __vm_allocate (__mach_task_self (), (vm_address_t *) values,
 170                            INIT_INT_MAX * sizeof (int), 1))
 171     return err;
 172   *nvalues = INIT_INT_MAX;
 173
 174   for (i = 0; i < INIT_INT_MAX; ++i)
 175     switch (err = get_int (i, &(*values)[i]))
 176       {
 177       case 0:                   /* Success.  */
 178         break;
 179       case EINVAL:              /* Unknown index.  */
 180         (*values)[i] = 0;
 181         break;
 182       default:                  /* Lossage.  */
 183         __vm_deallocate (__mach_task_self (),
 184                          (vm_address_t) *values, INIT_INT_MAX * sizeof (int));
 185         return err;
 186       }
 187
 188   return 0;
 189 }
 190
 191
 192 static kern_return_t
 193 set_int (int which, int value)
 194 {
 195   switch (which)
 196     {
 197     case INIT_UMASK:
 198       _hurd_umask = value;
 199       return 0;
 200
 201       /* These are pretty odd things to do.  But you asked for it.  */
 202     case INIT_SIGPENDING:
 203       {
 204         struct hurd_sigstate *ss = _hurd_global_sigstate;
 205         __spin_lock (&ss->lock);
 206         ss->pending = value;
 207         __spin_unlock (&ss->lock);
 208         return 0;
 209       }
 210     case INIT_SIGIGN:
 211       {
 212         struct hurd_sigstate *ss = _hurd_global_sigstate;
 213         int sig;
 214         const sigset_t ign = value;
 215         __spin_lock (&ss->lock);
 216         for (sig = 1; sig < NSIG; ++sig)
 217           {
 218             if (__sigismember (&ign, sig))
 219               ss->actions[sig].sa_handler = SIG_IGN;
 220             else if (ss->actions[sig].sa_handler == SIG_IGN)
 221               ss->actions[sig].sa_handler = SIG_DFL;
 222           }
 223         __spin_unlock (&ss->lock);
 224         return 0;
 225
 226       case INIT_TRACEMASK:
 227         _hurdsig_traced = value;
 228         return 0;
 229       }
 230     default:
 231       return EINVAL;
 232     }
 233 }
 234
 235 kern_return_t
 236 _S_msg_set_init_int (mach_port_t msgport, mach_port_t auth,
 237                      int which, int value)
 238 {
 239   AUTHCHECK;
 240
 241   return set_int (which, value);
 242 }
 243
 244 kern_return_t
 245 _S_msg_set_init_ints (mach_port_t msgport, mach_port_t auth,
 246                       const int *values, mach_msg_type_number_t nvalues)
 247 {
 248   error_t err;
 249   mach_msg_type_number_t i;
 250
 251   AUTHCHECK;
 252
 253   for (i = 0; i < INIT_INT_MAX; ++i)
 254     switch (err = set_int (i, values[i]))
 255       {
 256       case 0:                   /* Success.  */
 257         break;
 258       case EINVAL:              /* Unknown index.  */
 259         break;
 260       default:                  /* Lossage.  */
 261         return err;
 262       }
 263
 264   return 0;
 265 }
 266 \f
 267
 268 kern_return_t
 269 _S_msg_get_fd (mach_port_t msgport, mach_port_t auth, int which,
 270                mach_port_t *result, mach_msg_type_name_t *result_type)
 271 {
 272   AUTHCHECK;
 273
 274   /* This creates a new user reference for the send right.
 275      Our reply message will move that reference to the caller.  */
 276   *result = __getdport (which);
 277   if (*result == MACH_PORT_NULL)
 278     return errno;
 279   *result_type = MACH_MSG_TYPE_MOVE_SEND;
 280
 281   return 0;
 282 }
 283
 284 kern_return_t
 285 _S_msg_set_fd (mach_port_t msgport, mach_port_t auth,
 286                int which, mach_port_t port)
 287 {
 288   AUTHCHECK;
 289
 290   /* We consume the reference if successful.  */
 291   return HURD_FD_USE (which, (_hurd_port2fd (descriptor, port, 0), 0));
 292 }
 293 \f
 294 /* Snarfing and frobbing environment variables.  */
 295
 296 kern_return_t
 297 _S_msg_get_env_variable (mach_port_t msgport,
 298                          const_string_t variable, //
 299                          char **data, mach_msg_type_number_t *datalen)
 300 {
 301   error_t err;
 302   mach_msg_type_number_t valuelen;
 303   const char *value = getenv (variable);
 304
 305   if (value == NULL)
 306     return ENOENT;
 307
 308   valuelen = strlen (value);
 309   if (valuelen > *datalen)
 310     {
 311       if (err = __vm_allocate (__mach_task_self (),
 312                                (vm_address_t *) data, valuelen, 1))
 313         return err;
 314     }
 315
 316   memcpy (*data, value, valuelen);
 317   *datalen = valuelen;
 318
 319   return 0;
 320 }
 321
 322
 323 kern_return_t
 324 _S_msg_set_env_variable (mach_port_t msgport, mach_port_t auth,
 325                          const_string_t variable, //
 326                          const_string_t value, //
 327                          int replace)
 328 {
 329   AUTHCHECK;
 330
 331   if (__setenv (variable, value, replace)) /* XXX name space */
 332     return errno;
 333   return 0;
 334 }
 335
 336 kern_return_t
 337 _S_msg_get_environment (mach_port_t msgport,
 338                         char **data, mach_msg_type_number_t *datalen)
 339 {
 340   /* Pack the environment into an array with nulls separating elements.  */
 341   if (__environ != NULL)
 342     {
 343       char *ap, **p;
 344       size_t envlen = 0;
 345
 346       for (p = __environ; *p != NULL; ++p)
 347         envlen += strlen (*p) + 1;
 348
 349       if (envlen > *datalen)
 350         {
 351           if (__vm_allocate (__mach_task_self (),
 352                              (vm_address_t *) data, envlen, 1))
 353             return ENOMEM;
 354         }
 355
 356       ap = *data;
 357       for (p = __environ; *p != NULL; ++p)
 358         ap = __memccpy (ap, *p, '\0', ULONG_MAX);
 359
 360       *datalen = envlen;
 361     }
 362   else
 363     *datalen = 0;
 364
 365   return 0;
 366 }
 367
 368 kern_return_t
 369 _S_msg_set_environment (mach_port_t msgport, mach_port_t auth,
 370                         const char *data, mach_msg_type_number_t datalen)
 371 {
 372   int _hurd_split_args (char *, mach_msg_type_number_t, char **);
 373   int envc;
 374   char **envp;
 375
 376   AUTHCHECK;
 377
 378   envc = __argz_count (data, datalen);
 379   envp = malloc ((envc + 1) * sizeof (char *));
 380   if (envp == NULL)
 381     return errno;
 382   __argz_extract (data, datalen, envp);
 383   __environ = envp;             /* XXX cooperate with loadenv et al */
 384   return 0;
 385 }
 386 \f
 387
 388 kern_return_t
 389 _S_msg_get_dtable (mach_port_t process,
 390                    mach_port_t auth,
 391                    portarray_t *dtable,
 392                    mach_msg_type_name_t *dtablePoly,
 393                    mach_msg_type_number_t *dtableCnt)
 394 {
 395   mach_port_t *ports;
 396   mach_msg_type_number_t i;
 397   error_t err;
 398
 399   AUTHCHECK;
 400
 401   HURD_CRITICAL_BEGIN;
 402   __mutex_lock (&_hurd_dtable_lock);
 403
 404   if (err = __vm_allocate (__mach_task_self (), (vm_address_t *) &ports,
 405                            _hurd_dtablesize * sizeof(mach_port_t), 1))
 406     goto out;
 407
 408   for (i = 0; i < _hurd_dtablesize; i++)
 409     {
 410       struct hurd_fd *cell = _hurd_dtable[i];
 411       if (cell == NULL)
 412         ports[i] = MACH_PORT_NULL;
 413       else
 414         {
 415           __spin_lock (&cell->port.lock);
 416           if (cell->port.port == MACH_PORT_NULL)
 417             ports[i] = MACH_PORT_NULL;
 418           else
 419             {
 420               ports[i] = cell->port.port;
 421               /* We will move this send right.  */
 422               __mach_port_mod_refs (__mach_task_self (), ports[i],
 423                                     MACH_PORT_RIGHT_SEND, +1);
 424             }
 425           __spin_unlock (&cell->port.lock);
 426         }
 427     }
 428
 429   *dtable = ports;
 430   *dtablePoly = MACH_MSG_TYPE_MOVE_SEND;
 431   *dtableCnt = _hurd_dtablesize;
 432
 433 out:
 434   __mutex_unlock (&_hurd_dtable_lock);
 435   HURD_CRITICAL_END;
 436   return err;
 437 }
 438
 439 /* XXX */
 440
 441 kern_return_t
 442 _S_msg_set_dtable (mach_port_t process,
 443                    mach_port_t refport,
 444                    const_portarray_t dtable,
 445                    mach_msg_type_number_t dtableCnt)
 446 { return EOPNOTSUPP; }