src/daemon/dbus/tlm-dbus-server-p2p.c

   1 /* vi: set et sw=4 ts=4 cino=t0,(0: */
   2 /* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   3 /*
   4  * This file is part of tlm
   5  *
   6  * Copyright (C) 2014 Intel Corporation.
   7  *
   8  * Contact: Imran Zaman <imran.zaman@intel.com>
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with this library; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  23  * 02110-1301 USA
  24  */
  25 #include <errno.h>
  26 #include <string.h>
  27 #include <glib/gstdio.h>
  28 #include <unistd.h>
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <sys/stat.h>
  32 #include <fcntl.h>
  33
  34 #include "common/dbus/tlm-dbus.h"
  35 #include "common/tlm-log.h"
  36
  37 #include "tlm-dbus-server-p2p.h"
  38 #include "tlm-dbus-server-interface.h"
  39 #include "tlm-dbus-login-adapter.h"
  40
  41 enum
  42 {
  43     PROP_0,
  44
  45     IFACE_PROP_TYPE,
  46     PROP_ADDRESS,
  47
  48     N_PROPERTIES
  49 };
  50
  51 enum {
  52     SIG_CLIENT_ADDED,
  53     SIG_CLIENT_REMOVED,
  54
  55     SIG_MAX
  56 };
  57
  58 static guint signals[SIG_MAX];
  59
  60 struct _TlmDbusServerP2PPrivate
  61 {
  62     GHashTable *login_object_adapters;
  63     GDBusServer *bus_server;
  64     gchar *address;
  65     uid_t uid;
  66 };
  67
  68 static void
  69 _tlm_dbus_server_p2p_interface_init (
  70         TlmDbusServerInterface *iface);
  71
  72 gboolean
  73 _tlm_dbus_server_p2p_stop (
  74         TlmDbusServer *self);
  75
  76 static void
  77 _on_connection_closed (
  78         GDBusConnection *connection,
  79         gboolean remote_peer_vanished,
  80         GError *error,
  81         gpointer user_data);
  82
  83 G_DEFINE_TYPE_WITH_CODE (TlmDbusServerP2P,
  84         tlm_dbus_server_p2p, G_TYPE_OBJECT,
  85         G_IMPLEMENT_INTERFACE (TLM_TYPE_DBUS_SERVER,
  86                 _tlm_dbus_server_p2p_interface_init)
  87         G_ADD_PRIVATE(TlmDbusServerP2P));
  88
  89 static void
  90 _set_property (
  91         GObject *object,
  92         guint property_id,
  93         const GValue *value,
  94         GParamSpec *pspec)
  95 {
  96     TlmDbusServerP2P *self = TLM_DBUS_SERVER_P2P (object);
  97     switch (property_id) {
  98         case IFACE_PROP_TYPE: {
  99             break;
 100         }
 101         case PROP_ADDRESS: {
 102             self->priv->address = g_value_dup_string (value);
 103             break;
 104         }
 105         default:
 106             G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 107     }
 108 }
 109
 110 static void
 111 _get_property (
 112         GObject *object,
 113         guint property_id,
 114         GValue *value,
 115         GParamSpec *pspec)
 116 {
 117     TlmDbusServerP2P *self = TLM_DBUS_SERVER_P2P (object);
 118
 119     switch (property_id) {
 120         case IFACE_PROP_TYPE: {
 121             g_value_set_uint (value, (guint)TLM_DBUS_SERVER_BUSTYPE_P2P);
 122             break;
 123         }
 124         case PROP_ADDRESS: {
 125             g_value_set_string (value, g_dbus_server_get_client_address (
 126                     self->priv->bus_server));
 127             break;
 128         }
 129         default:
 130             G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 131     }
 132 }
 133
 134 static gboolean
 135 _compare_by_pointer (
 136         gpointer key,
 137         gpointer value,
 138         gpointer dead_object)
 139 {
 140     return value == dead_object;
 141 }
 142
 143 static void
 144 _on_login_object_dispose (
 145         gpointer data,
 146         GObject *dead)
 147 {
 148     TlmDbusServerP2P *server = TLM_DBUS_SERVER_P2P (data);
 149     g_return_if_fail (server);
 150     g_hash_table_foreach_steal (server->priv->login_object_adapters,
 151                 _compare_by_pointer, dead);
 152 }
 153
 154 static void
 155 _clear_login_object_watchers (
 156         gpointer connection,
 157         gpointer login_object,
 158         gpointer user_data)
 159 {
 160     g_signal_handlers_disconnect_by_func (connection, _on_connection_closed,
 161             user_data);
 162     g_object_weak_unref (G_OBJECT(login_object), _on_login_object_dispose,
 163             user_data);
 164 }
 165
 166 static void
 167 _add_login_object_watchers (
 168         gpointer connection,
 169         gpointer login_object,
 170         TlmDbusServerP2P *server)
 171 {
 172     g_signal_connect (connection, "closed", G_CALLBACK(_on_connection_closed),
 173             server);
 174     g_object_weak_ref (G_OBJECT (login_object), _on_login_object_dispose,
 175             server);
 176     g_hash_table_insert (server->priv->login_object_adapters, connection,
 177             login_object);
 178 }
 179
 180 static void
 181 _dispose (
 182         GObject *object)
 183 {
 184     TlmDbusServerP2P *self = TLM_DBUS_SERVER_P2P (object);
 185
 186     _tlm_dbus_server_p2p_stop (TLM_DBUS_SERVER (self));
 187
 188     G_OBJECT_CLASS (tlm_dbus_server_p2p_parent_class)->dispose (object);
 189 }
 190
 191 static void
 192 _finalize (
 193         GObject *object)
 194 {
 195     TlmDbusServerP2P *self = TLM_DBUS_SERVER_P2P (object);
 196     if (self->priv->address) {
 197         if (g_str_has_prefix (self->priv->address, "unix:path=")) {
 198             const gchar *path = g_strstr_len(self->priv->address, -1,
 199                     "unix:path=") + 10;
 200             if (path) {
 201                 g_unlink (path);
 202             }
 203         }
 204         g_free (self->priv->address);
 205         self->priv->address = NULL;
 206     }
 207     G_OBJECT_CLASS (tlm_dbus_server_p2p_parent_class)->finalize (object);
 208 }
 209
 210 static void
 211 tlm_dbus_server_p2p_class_init (
 212         TlmDbusServerP2PClass *klass)
 213 {
 214     GObjectClass* object_class = G_OBJECT_CLASS (klass);
 215     GParamSpec *address_spec = NULL;
 216
 217     object_class->get_property = _get_property;
 218     object_class->set_property = _set_property;
 219     object_class->dispose = _dispose;
 220     object_class->finalize = _finalize;
 221
 222     g_object_class_override_property (object_class, IFACE_PROP_TYPE, "bustype");
 223
 224     address_spec = g_param_spec_string ("address", "server address",
 225             "Server socket address",  NULL,
 226             G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
 227             G_PARAM_STATIC_STRINGS);
 228     g_object_class_install_property (object_class, PROP_ADDRESS, address_spec);
 229
 230     signals[SIG_CLIENT_ADDED] = g_signal_new ("client-added",
 231             TLM_TYPE_DBUS_SERVER_P2P,
 232             G_SIGNAL_RUN_LAST,
 233             0,
 234             NULL,
 235             NULL,
 236             NULL,
 237             G_TYPE_NONE,
 238             1,
 239             TLM_TYPE_LOGIN_ADAPTER);
 240
 241     signals[SIG_CLIENT_REMOVED] = g_signal_new ("client-removed",
 242             TLM_TYPE_DBUS_SERVER_P2P,
 243             G_SIGNAL_RUN_LAST,
 244             0,
 245             NULL,
 246             NULL,
 247             NULL,
 248             G_TYPE_NONE,
 249             1,
 250             TLM_TYPE_LOGIN_ADAPTER);
 251 }
 252
 253 static void
 254 tlm_dbus_server_p2p_init (
 255         TlmDbusServerP2P *self)
 256 {
 257     self->priv = tlm_dbus_server_p2p_get_instance_private (self);
 258     self->priv->bus_server = NULL;
 259     self->priv->address = NULL;
 260     self->priv->uid = 0;
 261     self->priv->login_object_adapters = g_hash_table_new_full (g_direct_hash,
 262             g_direct_equal, NULL, g_object_unref);
 263 }
 264
 265 static void
 266 _on_connection_closed (
 267         GDBusConnection *connection,
 268         gboolean remote_peer_vanished,
 269         GError *error,
 270         gpointer user_data)
 271 {
 272     TlmDbusServerP2P *server = TLM_DBUS_SERVER_P2P (user_data);
 273     gpointer login_object = g_hash_table_lookup (
 274             server->priv->login_object_adapters, connection);
 275     if  (login_object) {
 276         _clear_login_object_watchers (connection, login_object, user_data);
 277         DBG("p2p dbus connection(%p) closed (peer vanished : %d)"
 278                 " with error: %s", connection, remote_peer_vanished,
 279                 error ? error->message : "NONE");
 280
 281         g_signal_emit (server, signals[SIG_CLIENT_REMOVED], 0, login_object);
 282         g_hash_table_remove (server->priv->login_object_adapters, connection);
 283     }
 284 }
 285
 286 static void
 287 _tlm_dbus_server_p2p_add_login_obj (
 288         TlmDbusServerP2P *server,
 289         GDBusConnection *connection)
 290 {
 291     TlmDbusLoginAdapter *login_object = NULL;
 292
 293     DBG("export interfaces on connection %p", connection);
 294
 295     login_object = tlm_dbus_login_adapter_new_with_connection (connection);
 296
 297     _add_login_object_watchers (connection, login_object, server);
 298     g_signal_emit (server, signals[SIG_CLIENT_ADDED], 0, login_object);
 299 }
 300
 301 static gboolean
 302 _on_client_request (
 303         GDBusServer *dbus_server,
 304         GDBusConnection *connection,
 305         gpointer user_data)
 306 {
 307     TlmDbusServerP2P *server = TLM_DBUS_SERVER_P2P (user_data);
 308     if (!server) {
 309         WARN ("memory corruption");
 310         return TRUE;
 311     }
 312     _tlm_dbus_server_p2p_add_login_obj (server, connection);
 313     return TRUE;
 314 }
 315
 316 gboolean
 317 _tlm_dbus_server_p2p_start (
 318         TlmDbusServer *self)
 319 {
 320     g_return_val_if_fail (TLM_IS_DBUS_SERVER_P2P (self), FALSE);
 321
 322     DBG("start P2P DBus Server");
 323
 324     TlmDbusServerP2P *server = TLM_DBUS_SERVER_P2P (self);
 325     if (!server->priv->bus_server) {
 326         GError *err = NULL;
 327         gchar *guid = g_dbus_generate_guid ();
 328         server->priv->bus_server = g_dbus_server_new_sync (
 329                 server->priv->address, G_DBUS_SERVER_FLAGS_NONE, guid, NULL,
 330                 NULL, &err);
 331         g_free (guid);
 332
 333         if (!server->priv->bus_server) {
 334             WARN ("Failed to start server at address '%s':%s",
 335                     server->priv->address, err ? err->message : "NULL");
 336             g_error_free (err);
 337             return FALSE;
 338         }
 339
 340         g_signal_connect (server->priv->bus_server, "new-connection",
 341                 G_CALLBACK(_on_client_request), server);
 342     }
 343
 344     if (!g_dbus_server_is_active (server->priv->bus_server)) {
 345         const gchar *path = NULL;
 346         g_dbus_server_start (server->priv->bus_server);
 347         path = g_strstr_len(server->priv->address, -1, "unix:path=") + 10;
 348         if (path) {
 349             if (chown (path, server->priv->uid, -1) < 0) {
 350                 WARN("Unable to set ownership");
 351             }
 352             if (g_chmod (path, S_IRUSR | S_IWUSR) < 0) {
 353                 WARN("Unable to set mode '%d' for '%s'",
 354                     S_IRUSR|S_IWUSR, path);
 355             }
 356         }
 357     }
 358     DBG("dbus server started at : %s", server->priv->address);
 359
 360     return TRUE;
 361 }
 362
 363 gboolean
 364 _tlm_dbus_server_p2p_stop (
 365         TlmDbusServer *self)
 366 {
 367     g_return_val_if_fail (TLM_IS_DBUS_SERVER_P2P (self), FALSE);
 368     DBG ("self %p", self);
 369
 370     TlmDbusServerP2P *server = TLM_DBUS_SERVER_P2P (self);
 371
 372     if (server->priv->login_object_adapters) {
 373         DBG("cleanup watchers");
 374         g_hash_table_foreach (server->priv->login_object_adapters,
 375                 _clear_login_object_watchers, server);
 376         g_hash_table_unref (server->priv->login_object_adapters);
 377         server->priv->login_object_adapters = NULL;
 378     }
 379
 380     if (server->priv->bus_server) {
 381         DBG("stop P2P DBus Server");
 382         g_signal_handlers_disconnect_by_func (server->priv->bus_server,
 383                 _on_client_request, server);
 384         if (g_dbus_server_is_active (server->priv->bus_server))
 385             g_dbus_server_stop (server->priv->bus_server);
 386         g_object_unref (server->priv->bus_server);
 387         server->priv->bus_server = NULL;
 388     }
 389
 390     return TRUE;
 391 }
 392
 393 static pid_t
 394 _tlm_dbus_server_p2p_get_remote_pid (
 395         TlmDbusServer *self,
 396         GDBusMethodInvocation *invocation)
 397 {
 398     pid_t remote_pid = 0;
 399     GDBusConnection *connection = NULL;
 400     gint peer_fd = -1;
 401     struct ucred peer_cred;
 402     socklen_t cred_size = sizeof(peer_cred);
 403
 404     g_return_val_if_fail (invocation && TLM_IS_DBUS_SERVER_P2P (self),
 405             remote_pid);
 406
 407     connection = g_dbus_method_invocation_get_connection (invocation);
 408     peer_fd = g_socket_get_fd (g_socket_connection_get_socket (
 409             G_SOCKET_CONNECTION (g_dbus_connection_get_stream(connection))));
 410     if (peer_fd < 0 || getsockopt (peer_fd, SOL_SOCKET, SO_PEERCRED,
 411             &peer_cred, &cred_size) != 0) {
 412         WARN ("getsockopt() for SO_PEERCRED failed");
 413         return remote_pid;
 414     }
 415     DBG ("remote p2p peer pid=%d uid=%d gid=%d", peer_cred.pid, peer_cred.uid,
 416             peer_cred.gid);
 417
 418     return peer_cred.pid;
 419 }
 420
 421 static void
 422 _tlm_dbus_server_p2p_interface_init (
 423         TlmDbusServerInterface *iface)
 424 {
 425     iface->start = _tlm_dbus_server_p2p_start;
 426     iface->stop = _tlm_dbus_server_p2p_stop;
 427     iface->get_remote_pid = _tlm_dbus_server_p2p_get_remote_pid;
 428 }
 429
 430 TlmDbusServerP2P *
 431 tlm_dbus_server_p2p_new (
 432         const gchar *address,
 433         uid_t uid)
 434 {
 435     TlmDbusServerP2P *server = TLM_DBUS_SERVER_P2P (
 436         g_object_new (TLM_TYPE_DBUS_SERVER_P2P, "address", address, NULL));
 437
 438     DBG("create P2P DBus Server: %p", server);
 439     if (!server) {
 440         return NULL;
 441     }
 442     server->priv->uid = uid;
 443
 444     if (g_str_has_prefix(address, "unix:path=")) {
 445         const gchar *file_path = g_strstr_len (address, -1, "unix:path=") + 10;
 446
 447         if (g_file_test(file_path, G_FILE_TEST_EXISTS)) {
 448             g_unlink (file_path);
 449         }
 450         gchar *base_path = g_path_get_dirname (file_path);
 451
 452         if (g_mkdir_with_parents (base_path,
 453                 S_IRUSR |S_IWUSR |S_IXUSR |S_IXGRP |S_IXOTH) == -1) {
 454             gchar strerr_buf[MAX_STRERROR_LEN] = {0,};
 455             WARN ("Could not create '%s', error: %s", base_path,
 456                     strerror_r(errno, strerr_buf, MAX_STRERROR_LEN));
 457             g_object_unref (server);
 458             server = NULL;
 459         }
 460         g_free (base_path);
 461     }
 462
 463     return server;
 464 }