gio/gdbusauthmechanismexternal.c

   1 /* GDBus - GLib D-Bus Library
   2  *
   3  * Copyright (C) 2008-2010 Red Hat, Inc.
   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 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, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: David Zeuthen <davidz@redhat.com>
  21  */
  22
  23 #include "config.h"
  24
  25 #include <string.h>
  26
  27 #include "gdbusauthmechanismexternal.h"
  28 #include "gcredentials.h"
  29 #include "gdbuserror.h"
  30 #include "gioenumtypes.h"
  31
  32 #include "glibintl.h"
  33
  34 struct _GDBusAuthMechanismExternalPrivate
  35 {
  36   gboolean is_client;
  37   gboolean is_server;
  38   GDBusAuthMechanismState state;
  39 };
  40
  41 static gint                     mechanism_get_priority              (void);
  42 static const gchar             *mechanism_get_name                  (void);
  43
  44 static gboolean                 mechanism_is_supported              (GDBusAuthMechanism   *mechanism);
  45 static gchar                   *mechanism_encode_data               (GDBusAuthMechanism   *mechanism,
  46                                                                      const gchar          *data,
  47                                                                      gsize                 data_len,
  48                                                                      gsize                *out_data_len);
  49 static gchar                   *mechanism_decode_data               (GDBusAuthMechanism   *mechanism,
  50                                                                      const gchar          *data,
  51                                                                      gsize                 data_len,
  52                                                                      gsize                *out_data_len);
  53 static GDBusAuthMechanismState  mechanism_server_get_state          (GDBusAuthMechanism   *mechanism);
  54 static void                     mechanism_server_initiate           (GDBusAuthMechanism   *mechanism,
  55                                                                      const gchar          *initial_response,
  56                                                                      gsize                 initial_response_len);
  57 static void                     mechanism_server_data_receive       (GDBusAuthMechanism   *mechanism,
  58                                                                      const gchar          *data,
  59                                                                      gsize                 data_len);
  60 static gchar                   *mechanism_server_data_send          (GDBusAuthMechanism   *mechanism,
  61                                                                      gsize                *out_data_len);
  62 static gchar                   *mechanism_server_get_reject_reason  (GDBusAuthMechanism   *mechanism);
  63 static void                     mechanism_server_shutdown           (GDBusAuthMechanism   *mechanism);
  64 static GDBusAuthMechanismState  mechanism_client_get_state          (GDBusAuthMechanism   *mechanism);
  65 static gchar                   *mechanism_client_initiate           (GDBusAuthMechanism   *mechanism,
  66                                                                      gsize                *out_initial_response_len);
  67 static void                     mechanism_client_data_receive       (GDBusAuthMechanism   *mechanism,
  68                                                                      const gchar          *data,
  69                                                                      gsize                 data_len);
  70 static gchar                   *mechanism_client_data_send          (GDBusAuthMechanism   *mechanism,
  71                                                                      gsize                *out_data_len);
  72 static void                     mechanism_client_shutdown           (GDBusAuthMechanism   *mechanism);
  73
  74 /* ---------------------------------------------------------------------------------------------------- */
  75
  76 G_DEFINE_TYPE_WITH_PRIVATE (GDBusAuthMechanismExternal, _g_dbus_auth_mechanism_external, G_TYPE_DBUS_AUTH_MECHANISM)
  77
  78 /* ---------------------------------------------------------------------------------------------------- */
  79
  80 static void
  81 _g_dbus_auth_mechanism_external_finalize (GObject *object)
  82 {
  83   //GDBusAuthMechanismExternal *mechanism = G_DBUS_AUTH_MECHANISM_EXTERNAL (object);
  84
  85   if (G_OBJECT_CLASS (_g_dbus_auth_mechanism_external_parent_class)->finalize != NULL)
  86     G_OBJECT_CLASS (_g_dbus_auth_mechanism_external_parent_class)->finalize (object);
  87 }
  88
  89 static void
  90 _g_dbus_auth_mechanism_external_class_init (GDBusAuthMechanismExternalClass *klass)
  91 {
  92   GObjectClass *gobject_class;
  93   GDBusAuthMechanismClass *mechanism_class;
  94
  95   gobject_class = G_OBJECT_CLASS (klass);
  96   gobject_class->finalize = _g_dbus_auth_mechanism_external_finalize;
  97
  98   mechanism_class = G_DBUS_AUTH_MECHANISM_CLASS (klass);
  99   mechanism_class->get_name                  = mechanism_get_name;
 100   mechanism_class->get_priority              = mechanism_get_priority;
 101   mechanism_class->is_supported              = mechanism_is_supported;
 102   mechanism_class->encode_data               = mechanism_encode_data;
 103   mechanism_class->decode_data               = mechanism_decode_data;
 104   mechanism_class->server_get_state          = mechanism_server_get_state;
 105   mechanism_class->server_initiate           = mechanism_server_initiate;
 106   mechanism_class->server_data_receive       = mechanism_server_data_receive;
 107   mechanism_class->server_data_send          = mechanism_server_data_send;
 108   mechanism_class->server_get_reject_reason  = mechanism_server_get_reject_reason;
 109   mechanism_class->server_shutdown           = mechanism_server_shutdown;
 110   mechanism_class->client_get_state          = mechanism_client_get_state;
 111   mechanism_class->client_initiate           = mechanism_client_initiate;
 112   mechanism_class->client_data_receive       = mechanism_client_data_receive;
 113   mechanism_class->client_data_send          = mechanism_client_data_send;
 114   mechanism_class->client_shutdown           = mechanism_client_shutdown;
 115 }
 116
 117 static void
 118 _g_dbus_auth_mechanism_external_init (GDBusAuthMechanismExternal *mechanism)
 119 {
 120   mechanism->priv = _g_dbus_auth_mechanism_external_get_instance_private (mechanism);
 121 }
 122
 123 /* ---------------------------------------------------------------------------------------------------- */
 124
 125 static gboolean
 126 mechanism_is_supported (GDBusAuthMechanism *mechanism)
 127 {
 128   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), FALSE);
 129   /* This mechanism is only available if credentials has been exchanged */
 130   if (_g_dbus_auth_mechanism_get_credentials (mechanism) != NULL)
 131     return TRUE;
 132   else
 133     return FALSE;
 134 }
 135
 136 static gint
 137 mechanism_get_priority (void)
 138 {
 139   /* We prefer EXTERNAL to most other mechanism (DBUS_COOKIE_SHA1 and ANONYMOUS) */
 140   return 100;
 141 }
 142
 143 static const gchar *
 144 mechanism_get_name (void)
 145 {
 146   return "EXTERNAL";
 147 }
 148
 149 static gchar *
 150 mechanism_encode_data (GDBusAuthMechanism   *mechanism,
 151                        const gchar          *data,
 152                        gsize                 data_len,
 153                        gsize                *out_data_len)
 154 {
 155   return NULL;
 156 }
 157
 158
 159 static gchar *
 160 mechanism_decode_data (GDBusAuthMechanism   *mechanism,
 161                        const gchar          *data,
 162                        gsize                 data_len,
 163                        gsize                *out_data_len)
 164 {
 165   return NULL;
 166 }
 167
 168 /* ---------------------------------------------------------------------------------------------------- */
 169
 170 static GDBusAuthMechanismState
 171 mechanism_server_get_state (GDBusAuthMechanism   *mechanism)
 172 {
 173   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 174
 175   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), G_DBUS_AUTH_MECHANISM_STATE_INVALID);
 176   g_return_val_if_fail (m->priv->is_server && !m->priv->is_client, G_DBUS_AUTH_MECHANISM_STATE_INVALID);
 177
 178   return m->priv->state;
 179 }
 180
 181 static gboolean
 182 data_matches_credentials (const gchar *data,
 183                           GCredentials *credentials)
 184 {
 185   gboolean match;
 186
 187   match = FALSE;
 188
 189   if (credentials == NULL)
 190     goto out;
 191
 192   if (data == NULL || strlen (data) == 0)
 193     goto out;
 194
 195 #if defined(G_OS_UNIX)
 196   {
 197     gint64 alleged_uid;
 198     gchar *endp;
 199
 200     /* on UNIX, this is the uid as a string in base 10 */
 201     alleged_uid = g_ascii_strtoll (data, &endp, 10);
 202     if (*endp == '\0')
 203       {
 204         if (g_credentials_get_unix_user (credentials, NULL) == alleged_uid)
 205           {
 206             match = TRUE;
 207           }
 208       }
 209   }
 210 #else
 211   /* TODO: Dont know how to compare credentials on this OS. Please implement. */
 212 #endif
 213
 214  out:
 215   return match;
 216 }
 217
 218 static void
 219 mechanism_server_initiate (GDBusAuthMechanism   *mechanism,
 220                            const gchar          *initial_response,
 221                            gsize                 initial_response_len)
 222 {
 223   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 224
 225   g_return_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism));
 226   g_return_if_fail (!m->priv->is_server && !m->priv->is_client);
 227
 228   m->priv->is_server = TRUE;
 229
 230   if (initial_response != NULL)
 231     {
 232       if (data_matches_credentials (initial_response, _g_dbus_auth_mechanism_get_credentials (mechanism)))
 233         {
 234           m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_ACCEPTED;
 235         }
 236       else
 237         {
 238           m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_REJECTED;
 239         }
 240     }
 241   else
 242     {
 243       m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_WAITING_FOR_DATA;
 244     }
 245 }
 246
 247 static void
 248 mechanism_server_data_receive (GDBusAuthMechanism   *mechanism,
 249                                const gchar          *data,
 250                                gsize                 data_len)
 251 {
 252   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 253
 254   g_return_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism));
 255   g_return_if_fail (m->priv->is_server && !m->priv->is_client);
 256   g_return_if_fail (m->priv->state == G_DBUS_AUTH_MECHANISM_STATE_WAITING_FOR_DATA);
 257
 258   if (data_matches_credentials (data, _g_dbus_auth_mechanism_get_credentials (mechanism)))
 259     {
 260       m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_ACCEPTED;
 261     }
 262   else
 263     {
 264       m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_REJECTED;
 265     }
 266 }
 267
 268 static gchar *
 269 mechanism_server_data_send (GDBusAuthMechanism   *mechanism,
 270                             gsize                *out_data_len)
 271 {
 272   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 273
 274   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), NULL);
 275   g_return_val_if_fail (m->priv->is_server && !m->priv->is_client, NULL);
 276   g_return_val_if_fail (m->priv->state == G_DBUS_AUTH_MECHANISM_STATE_HAVE_DATA_TO_SEND, NULL);
 277
 278   /* can never end up here because we are never in the HAVE_DATA_TO_SEND state */
 279   g_assert_not_reached ();
 280
 281   return NULL;
 282 }
 283
 284 static gchar *
 285 mechanism_server_get_reject_reason (GDBusAuthMechanism   *mechanism)
 286 {
 287   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 288
 289   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), NULL);
 290   g_return_val_if_fail (m->priv->is_server && !m->priv->is_client, NULL);
 291   g_return_val_if_fail (m->priv->state == G_DBUS_AUTH_MECHANISM_STATE_REJECTED, NULL);
 292
 293   /* can never end up here because we are never in the REJECTED state */
 294   g_assert_not_reached ();
 295
 296   return NULL;
 297 }
 298
 299 static void
 300 mechanism_server_shutdown (GDBusAuthMechanism   *mechanism)
 301 {
 302   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 303
 304   g_return_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism));
 305   g_return_if_fail (m->priv->is_server && !m->priv->is_client);
 306
 307   m->priv->is_server = FALSE;
 308 }
 309
 310 /* ---------------------------------------------------------------------------------------------------- */
 311
 312 static GDBusAuthMechanismState
 313 mechanism_client_get_state (GDBusAuthMechanism   *mechanism)
 314 {
 315   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 316
 317   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), G_DBUS_AUTH_MECHANISM_STATE_INVALID);
 318   g_return_val_if_fail (m->priv->is_client && !m->priv->is_server, G_DBUS_AUTH_MECHANISM_STATE_INVALID);
 319
 320   return m->priv->state;
 321 }
 322
 323 static gchar *
 324 mechanism_client_initiate (GDBusAuthMechanism   *mechanism,
 325                            gsize                *out_initial_response_len)
 326 {
 327   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 328   gchar *initial_response;
 329   GCredentials *credentials;
 330
 331   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), NULL);
 332   g_return_val_if_fail (!m->priv->is_server && !m->priv->is_client, NULL);
 333
 334   m->priv->is_client = TRUE;
 335   m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_ACCEPTED;
 336
 337   *out_initial_response_len = -1;
 338
 339   credentials = _g_dbus_auth_mechanism_get_credentials (mechanism);
 340   g_assert (credentials != NULL);
 341
 342   /* return the uid */
 343 #if defined(G_OS_UNIX)
 344   initial_response = g_strdup_printf ("%" G_GINT64_FORMAT, (gint64) g_credentials_get_unix_user (credentials, NULL));
 345 #elif defined(G_OS_WIN32)
 346 #ifdef __GNUC__
 347 #warning Dont know how to send credentials on this OS. The EXTERNAL D-Bus authentication mechanism will not work.
 348 #endif
 349   m->priv->state = G_DBUS_AUTH_MECHANISM_STATE_REJECTED;
 350 #endif
 351   return initial_response;
 352 }
 353
 354 static void
 355 mechanism_client_data_receive (GDBusAuthMechanism   *mechanism,
 356                                const gchar          *data,
 357                                gsize                 data_len)
 358 {
 359   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 360
 361   g_return_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism));
 362   g_return_if_fail (m->priv->is_client && !m->priv->is_server);
 363   g_return_if_fail (m->priv->state == G_DBUS_AUTH_MECHANISM_STATE_WAITING_FOR_DATA);
 364
 365   /* can never end up here because we are never in the WAITING_FOR_DATA state */
 366   g_assert_not_reached ();
 367 }
 368
 369 static gchar *
 370 mechanism_client_data_send (GDBusAuthMechanism   *mechanism,
 371                             gsize                *out_data_len)
 372 {
 373   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 374
 375   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism), NULL);
 376   g_return_val_if_fail (m->priv->is_client && !m->priv->is_server, NULL);
 377   g_return_val_if_fail (m->priv->state == G_DBUS_AUTH_MECHANISM_STATE_HAVE_DATA_TO_SEND, NULL);
 378
 379   /* can never end up here because we are never in the HAVE_DATA_TO_SEND state */
 380   g_assert_not_reached ();
 381
 382   return NULL;
 383 }
 384
 385 static void
 386 mechanism_client_shutdown (GDBusAuthMechanism   *mechanism)
 387 {
 388   GDBusAuthMechanismExternal *m = G_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism);
 389
 390   g_return_if_fail (G_IS_DBUS_AUTH_MECHANISM_EXTERNAL (mechanism));
 391   g_return_if_fail (m->priv->is_client && !m->priv->is_server);
 392
 393   m->priv->is_client = FALSE;
 394 }
 395
 396 /* ---------------------------------------------------------------------------------------------------- */