gio/gunixsocketaddress.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2008 Christian Kellner, Samuel Cormier-Iijima
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Authors: Christian Kellner <gicmo@gnome.org>
  19  *          Samuel Cormier-Iijima <sciyoshi@gmail.com>
  20  */
  21
  22 #include <config.h>
  23 #include <glib.h>
  24 #include <string.h>
  25
  26 #include "gunixsocketaddress.h"
  27 #include "gsocketconnectable.h"
  28 #include "glibintl.h"
  29 #include "gnetworking.h"
  30
  31
  32 /**
  33  * SECTION:gunixsocketaddress
  34  * @short_description: UNIX GSocketAddress
  35  * @include: gio/gunixsocketaddress.h
  36  *
  37  * Support for UNIX-domain (also known as local) sockets.
  38  *
  39  * UNIX domain sockets are generally visible in the filesystem.
  40  * However, some systems support abstract socket names which are not
  41  * visible in the filesystem and not affected by the filesystem
  42  * permissions, visibility, etc. Currently this is only supported
  43  * under Linux. If you attempt to use abstract sockets on other
  44  * systems, function calls may return %G_IO_ERROR_NOT_SUPPORTED
  45  * errors. You can use g_unix_socket_address_abstract_names_supported()
  46  * to see if abstract names are supported.
  47  *
  48  * Note that `<gio/gunixsocketaddress.h>` belongs to the UNIX-specific GIO
  49  * interfaces, thus you have to use the `gio-unix-2.0.pc` pkg-config file
  50  * when using it.
  51  */
  52
  53 /**
  54  * GUnixSocketAddress:
  55  *
  56  * A UNIX-domain (local) socket address, corresponding to a
  57  * struct sockaddr_un.
  58  */
  59
  60 enum
  61 {
  62   PROP_0,
  63   PROP_PATH,
  64   PROP_PATH_AS_ARRAY,
  65   PROP_ABSTRACT,
  66   PROP_ADDRESS_TYPE
  67 };
  68
  69 #ifndef UNIX_PATH_MAX
  70 #define UNIX_PATH_MAX G_SIZEOF_MEMBER (struct sockaddr_un, sun_path)
  71 #endif
  72
  73 struct _GUnixSocketAddressPrivate
  74 {
  75   char path[UNIX_PATH_MAX]; /* Not including the initial zero in abstract case, so
  76                                we can guarantee zero termination of abstract
  77                                pathnames in the get_path() API */
  78   gsize path_len; /* Not including any terminating zeros */
  79   GUnixSocketAddressType address_type;
  80 };
  81
  82 static void   g_unix_socket_address_connectable_iface_init (GSocketConnectableIface *iface);
  83 static gchar *g_unix_socket_address_connectable_to_string  (GSocketConnectable      *connectable);
  84
  85 G_DEFINE_TYPE_WITH_CODE (GUnixSocketAddress, g_unix_socket_address, G_TYPE_SOCKET_ADDRESS,
  86                          G_ADD_PRIVATE (GUnixSocketAddress)
  87                          G_IMPLEMENT_INTERFACE (G_TYPE_SOCKET_CONNECTABLE,
  88                                                 g_unix_socket_address_connectable_iface_init))
  89
  90 static void
  91 g_unix_socket_address_set_property (GObject      *object,
  92                                     guint         prop_id,
  93                                     const GValue *value,
  94                                     GParamSpec   *pspec)
  95 {
  96   GUnixSocketAddress *address = G_UNIX_SOCKET_ADDRESS (object);
  97   const char *str;
  98   GByteArray *array;
  99   gsize len;
 100
 101   switch (prop_id)
 102     {
 103     case PROP_PATH:
 104       str = g_value_get_string (value);
 105       if (str)
 106         {
 107           g_strlcpy (address->priv->path, str,
 108                      sizeof (address->priv->path));
 109           address->priv->path_len = strlen (address->priv->path);
 110         }
 111       break;
 112
 113     case PROP_PATH_AS_ARRAY:
 114       array = g_value_get_boxed (value);
 115
 116       if (array)
 117         {
 118           /* Clip to fit in UNIX_PATH_MAX with zero termination or first byte */
 119           len = MIN (array->len, UNIX_PATH_MAX-1);
 120
 121           if (len != 0)
 122             memcpy (address->priv->path, array->data, len);
 123
 124           address->priv->path[len] = 0; /* Ensure null-terminated */
 125           address->priv->path_len = len;
 126         }
 127       break;
 128
 129     case PROP_ABSTRACT:
 130       /* Only set it if it's not the default... */
 131       if (g_value_get_boolean (value))
 132        address->priv->address_type = G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED;
 133       break;
 134
 135     case PROP_ADDRESS_TYPE:
 136       /* Only set it if it's not the default... */
 137       if (g_value_get_enum (value) != G_UNIX_SOCKET_ADDRESS_PATH)
 138         address->priv->address_type = g_value_get_enum (value);
 139       break;
 140
 141     default:
 142       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 143     }
 144 }
 145
 146 static void
 147 g_unix_socket_address_get_property (GObject    *object,
 148                                     guint       prop_id,
 149                                     GValue     *value,
 150                                     GParamSpec *pspec)
 151 {
 152   GUnixSocketAddress *address = G_UNIX_SOCKET_ADDRESS (object);
 153   GByteArray *array;
 154
 155   switch (prop_id)
 156     {
 157       case PROP_PATH:
 158         g_value_set_string (value, address->priv->path);
 159         break;
 160
 161       case PROP_PATH_AS_ARRAY:
 162         array = g_byte_array_sized_new (address->priv->path_len);
 163         g_byte_array_append (array, (guint8 *)address->priv->path, address->priv->path_len);
 164         g_value_take_boxed (value, array);
 165         break;
 166
 167       case PROP_ABSTRACT:
 168         g_value_set_boolean (value, (address->priv->address_type == G_UNIX_SOCKET_ADDRESS_ABSTRACT ||
 169                                      address->priv->address_type == G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED));
 170
 171         break;
 172
 173       case PROP_ADDRESS_TYPE:
 174         g_value_set_enum (value, address->priv->address_type);
 175         break;
 176
 177       default:
 178         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 179     }
 180 }
 181
 182 static GSocketFamily
 183 g_unix_socket_address_get_family (GSocketAddress *address)
 184 {
 185   g_assert (PF_UNIX == G_SOCKET_FAMILY_UNIX);
 186
 187   return G_SOCKET_FAMILY_UNIX;
 188 }
 189
 190 static gssize
 191 g_unix_socket_address_get_native_size (GSocketAddress *address)
 192 {
 193   GUnixSocketAddress *addr = G_UNIX_SOCKET_ADDRESS (address);
 194
 195   switch (addr->priv->address_type)
 196     {
 197     case G_UNIX_SOCKET_ADDRESS_ANONYMOUS:
 198       return G_STRUCT_OFFSET(struct sockaddr_un, sun_path);
 199     case G_UNIX_SOCKET_ADDRESS_ABSTRACT:
 200       return G_STRUCT_OFFSET(struct sockaddr_un, sun_path) + addr->priv->path_len + 1;
 201     default:
 202       return sizeof (struct sockaddr_un);
 203     }
 204 }
 205
 206 static gboolean
 207 g_unix_socket_address_to_native (GSocketAddress *address,
 208                                  gpointer        dest,
 209                                  gsize           destlen,
 210                                  GError        **error)
 211 {
 212   GUnixSocketAddress *addr = G_UNIX_SOCKET_ADDRESS (address);
 213   struct sockaddr_un *sock;
 214   gssize socklen;
 215
 216   socklen = g_unix_socket_address_get_native_size (address);
 217   if (destlen < socklen)
 218     {
 219       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NO_SPACE,
 220                            _("Not enough space for socket address"));
 221       return FALSE;
 222     }
 223
 224   sock = (struct sockaddr_un *) dest;
 225   memset (sock, 0, socklen);
 226   sock->sun_family = AF_UNIX;
 227
 228   switch (addr->priv->address_type)
 229     {
 230     case G_UNIX_SOCKET_ADDRESS_INVALID:
 231     case G_UNIX_SOCKET_ADDRESS_ANONYMOUS:
 232       break;
 233
 234     case G_UNIX_SOCKET_ADDRESS_PATH:
 235       strcpy (sock->sun_path, addr->priv->path);
 236       break;
 237
 238     case G_UNIX_SOCKET_ADDRESS_ABSTRACT:
 239     case G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED:
 240       if (!g_unix_socket_address_abstract_names_supported ())
 241         {
 242           g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 243                                _("Abstract UNIX domain socket addresses not supported on this system"));
 244           return FALSE;
 245         }
 246
 247       sock->sun_path[0] = 0;
 248       memcpy (sock->sun_path+1, addr->priv->path, addr->priv->path_len);
 249       break;
 250     }
 251
 252   return TRUE;
 253 }
 254
 255 static void
 256 g_unix_socket_address_class_init (GUnixSocketAddressClass *klass)
 257 {
 258   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 259   GSocketAddressClass *gsocketaddress_class = G_SOCKET_ADDRESS_CLASS (klass);
 260
 261   gobject_class->set_property = g_unix_socket_address_set_property;
 262   gobject_class->get_property = g_unix_socket_address_get_property;
 263
 264   gsocketaddress_class->get_family = g_unix_socket_address_get_family;
 265   gsocketaddress_class->to_native = g_unix_socket_address_to_native;
 266   gsocketaddress_class->get_native_size = g_unix_socket_address_get_native_size;
 267
 268   g_object_class_install_property (gobject_class,
 269                                    PROP_PATH,
 270                                    g_param_spec_string ("path",
 271                                                         P_("Path"),
 272                                                         P_("UNIX socket path"),
 273                                                         NULL,
 274                                                         G_PARAM_READWRITE |
 275                                                         G_PARAM_CONSTRUCT_ONLY |
 276                                                         G_PARAM_STATIC_STRINGS));
 277   g_object_class_install_property (gobject_class, PROP_PATH_AS_ARRAY,
 278                                    g_param_spec_boxed ("path-as-array",
 279                                                        P_("Path array"),
 280                                                        P_("UNIX socket path, as byte array"),
 281                                                        G_TYPE_BYTE_ARRAY,
 282                                                        G_PARAM_READWRITE |
 283                                                        G_PARAM_CONSTRUCT_ONLY |
 284                                                        G_PARAM_STATIC_STRINGS));
 285   /**
 286    * GUnixSocketAddress:abstract:
 287    *
 288    * Whether or not this is an abstract address
 289    *
 290    * Deprecated: Use #GUnixSocketAddress:address-type, which
 291    * distinguishes between zero-padded and non-zero-padded
 292    * abstract addresses.
 293    */
 294   g_object_class_install_property (gobject_class, PROP_ABSTRACT,
 295                                    g_param_spec_boolean ("abstract",
 296                                                          P_("Abstract"),
 297                                                          P_("Whether or not this is an abstract address"),
 298                                                          FALSE,
 299                                                          G_PARAM_READWRITE |
 300                                                          G_PARAM_CONSTRUCT_ONLY |
 301                                                          G_PARAM_STATIC_STRINGS));
 302   g_object_class_install_property (gobject_class, PROP_ADDRESS_TYPE,
 303                                    g_param_spec_enum ("address-type",
 304                                                       P_("Address type"),
 305                                                       P_("The type of UNIX socket address"),
 306                                                       G_TYPE_UNIX_SOCKET_ADDRESS_TYPE,
 307                                                       G_UNIX_SOCKET_ADDRESS_PATH,
 308                                                       G_PARAM_READWRITE |
 309                                                       G_PARAM_CONSTRUCT_ONLY |
 310                                                       G_PARAM_STATIC_STRINGS));
 311 }
 312
 313 static void
 314 g_unix_socket_address_connectable_iface_init (GSocketConnectableIface *iface)
 315 {
 316   GSocketConnectableIface *parent_iface = g_type_interface_peek_parent (iface);
 317
 318   iface->enumerate = parent_iface->enumerate;
 319   iface->proxy_enumerate = parent_iface->proxy_enumerate;
 320   iface->to_string = g_unix_socket_address_connectable_to_string;
 321 }
 322
 323 static gchar *
 324 g_unix_socket_address_connectable_to_string (GSocketConnectable *connectable)
 325 {
 326   GUnixSocketAddress *ua;
 327   GString *out;
 328   const gchar *path;
 329   gsize path_len, i;
 330
 331   ua = G_UNIX_SOCKET_ADDRESS (connectable);
 332
 333   /* Anonymous sockets have no path. */
 334   if (ua->priv->address_type == G_UNIX_SOCKET_ADDRESS_ANONYMOUS)
 335     return g_strdup ("anonymous");
 336
 337   path = g_unix_socket_address_get_path (ua);
 338   path_len = g_unix_socket_address_get_path_len (ua);
 339   out = g_string_sized_new (path_len);
 340
 341   /* Return the #GUnixSocketAddress:path, but with all non-printable characters
 342    * (including nul bytes) escaped to hex. */
 343   for (i = 0; i < path_len; i++)
 344     {
 345       guint8 c = path[i];
 346
 347       if (g_ascii_isprint (path[i]))
 348         g_string_append_c (out, c);
 349       else
 350         g_string_append_printf (out, "\\x%02x", (guint) c);
 351     }
 352
 353   return g_string_free (out, FALSE);
 354 }
 355
 356 static void
 357 g_unix_socket_address_init (GUnixSocketAddress *address)
 358 {
 359   address->priv = g_unix_socket_address_get_instance_private (address);
 360
 361   memset (address->priv->path, 0, sizeof (address->priv->path));
 362   address->priv->path_len = -1;
 363   address->priv->address_type = G_UNIX_SOCKET_ADDRESS_PATH;
 364 }
 365
 366 /**
 367  * g_unix_socket_address_new:
 368  * @path: the socket path
 369  *
 370  * Creates a new #GUnixSocketAddress for @path.
 371  *
 372  * To create abstract socket addresses, on systems that support that,
 373  * use g_unix_socket_address_new_abstract().
 374  *
 375  * Returns: a new #GUnixSocketAddress
 376  *
 377  * Since: 2.22
 378  */
 379 GSocketAddress *
 380 g_unix_socket_address_new (const gchar *path)
 381 {
 382   return g_object_new (G_TYPE_UNIX_SOCKET_ADDRESS,
 383                        "path", path,
 384                        "abstract", FALSE,
 385                        NULL);
 386 }
 387
 388 /**
 389  * g_unix_socket_address_new_abstract:
 390  * @path: (array length=path_len) (element-type gchar): the abstract name
 391  * @path_len: the length of @path, or -1
 392  *
 393  * Creates a new %G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED
 394  * #GUnixSocketAddress for @path.
 395  *
 396  * Returns: a new #GUnixSocketAddress
 397  *
 398  * Deprecated: Use g_unix_socket_address_new_with_type().
 399  */
 400 GSocketAddress *
 401 g_unix_socket_address_new_abstract (const gchar *path,
 402                                     gint         path_len)
 403 {
 404   return g_unix_socket_address_new_with_type (path, path_len,
 405                                               G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED);
 406 }
 407
 408 /**
 409  * g_unix_socket_address_new_with_type:
 410  * @path: (array length=path_len) (element-type gchar): the name
 411  * @path_len: the length of @path, or -1
 412  * @type: a #GUnixSocketAddressType
 413  *
 414  * Creates a new #GUnixSocketAddress of type @type with name @path.
 415  *
 416  * If @type is %G_UNIX_SOCKET_ADDRESS_PATH, this is equivalent to
 417  * calling g_unix_socket_address_new().
 418  *
 419  * If @type is %G_UNIX_SOCKET_ADDRESS_ANONYMOUS, @path and @path_len will be
 420  * ignored.
 421  *
 422  * If @path_type is %G_UNIX_SOCKET_ADDRESS_ABSTRACT, then @path_len
 423  * bytes of @path will be copied to the socket's path, and only those
 424  * bytes will be considered part of the name. (If @path_len is -1,
 425  * then @path is assumed to be NUL-terminated.) For example, if @path
 426  * was "test", then calling g_socket_address_get_native_size() on the
 427  * returned socket would return 7 (2 bytes of overhead, 1 byte for the
 428  * abstract-socket indicator byte, and 4 bytes for the name "test").
 429  *
 430  * If @path_type is %G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED, then
 431  * @path_len bytes of @path will be copied to the socket's path, the
 432  * rest of the path will be padded with 0 bytes, and the entire
 433  * zero-padded buffer will be considered the name. (As above, if
 434  * @path_len is -1, then @path is assumed to be NUL-terminated.) In
 435  * this case, g_socket_address_get_native_size() will always return
 436  * the full size of a `struct sockaddr_un`, although
 437  * g_unix_socket_address_get_path_len() will still return just the
 438  * length of @path.
 439  *
 440  * %G_UNIX_SOCKET_ADDRESS_ABSTRACT is preferred over
 441  * %G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED for new programs. Of course,
 442  * when connecting to a server created by another process, you must
 443  * use the appropriate type corresponding to how that process created
 444  * its listening socket.
 445  *
 446  * Returns: a new #GUnixSocketAddress
 447  *
 448  * Since: 2.26
 449  */
 450 GSocketAddress *
 451 g_unix_socket_address_new_with_type (const gchar            *path,
 452                                      gint                    path_len,
 453                                      GUnixSocketAddressType  type)
 454 {
 455   GSocketAddress *address;
 456   GByteArray *array;
 457
 458   if (type == G_UNIX_SOCKET_ADDRESS_ANONYMOUS)
 459     path_len = 0;
 460   else if (path_len == -1)
 461     path_len = strlen (path);
 462
 463   array = g_byte_array_sized_new (path_len);
 464
 465   g_byte_array_append (array, (guint8 *)path, path_len);
 466
 467   address = g_object_new (G_TYPE_UNIX_SOCKET_ADDRESS,
 468                           "path-as-array", array,
 469                           "address-type", type,
 470                           NULL);
 471
 472   g_byte_array_unref (array);
 473
 474   return address;
 475 }
 476
 477 /**
 478  * g_unix_socket_address_get_path:
 479  * @address: a #GInetSocketAddress
 480  *
 481  * Gets @address's path, or for abstract sockets the "name".
 482  *
 483  * Guaranteed to be zero-terminated, but an abstract socket
 484  * may contain embedded zeros, and thus you should use
 485  * g_unix_socket_address_get_path_len() to get the true length
 486  * of this string.
 487  *
 488  * Returns: the path for @address
 489  *
 490  * Since: 2.22
 491  */
 492 const char *
 493 g_unix_socket_address_get_path (GUnixSocketAddress *address)
 494 {
 495   return address->priv->path;
 496 }
 497
 498 /**
 499  * g_unix_socket_address_get_path_len:
 500  * @address: a #GInetSocketAddress
 501  *
 502  * Gets the length of @address's path.
 503  *
 504  * For details, see g_unix_socket_address_get_path().
 505  *
 506  * Returns: the length of the path
 507  *
 508  * Since: 2.22
 509  */
 510 gsize
 511 g_unix_socket_address_get_path_len (GUnixSocketAddress *address)
 512 {
 513   return address->priv->path_len;
 514 }
 515
 516 /**
 517  * g_unix_socket_address_get_address_type:
 518  * @address: a #GInetSocketAddress
 519  *
 520  * Gets @address's type.
 521  *
 522  * Returns: a #GUnixSocketAddressType
 523  *
 524  * Since: 2.26
 525  */
 526 GUnixSocketAddressType
 527 g_unix_socket_address_get_address_type (GUnixSocketAddress *address)
 528 {
 529   return address->priv->address_type;
 530 }
 531
 532 /**
 533  * g_unix_socket_address_get_is_abstract:
 534  * @address: a #GInetSocketAddress
 535  *
 536  * Tests if @address is abstract.
 537  *
 538  * Returns: %TRUE if the address is abstract, %FALSE otherwise
 539  *
 540  * Since: 2.22
 541  *
 542  * Deprecated: Use g_unix_socket_address_get_address_type()
 543  */
 544 gboolean
 545 g_unix_socket_address_get_is_abstract (GUnixSocketAddress *address)
 546 {
 547   return (address->priv->address_type == G_UNIX_SOCKET_ADDRESS_ABSTRACT ||
 548           address->priv->address_type == G_UNIX_SOCKET_ADDRESS_ABSTRACT_PADDED);
 549 }
 550
 551 /**
 552  * g_unix_socket_address_abstract_names_supported:
 553  *
 554  * Checks if abstract UNIX domain socket names are supported.
 555  *
 556  * Returns: %TRUE if supported, %FALSE otherwise
 557  *
 558  * Since: 2.22
 559  */
 560 gboolean
 561 g_unix_socket_address_abstract_names_supported (void)
 562 {
 563 #ifdef __linux__
 564   return TRUE;
 565 #else
 566   return FALSE;
 567 #endif
 568 }