gio/gcredentials.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, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Author: David Zeuthen <davidz@redhat.com>
  19  */
  20
  21 #include "config.h"
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #include <gobject/gvaluecollector.h>
  27
  28 #include "gcredentials.h"
  29 #include "gcredentialsprivate.h"
  30 #include "gnetworking.h"
  31 #include "gioerror.h"
  32 #include "gioenumtypes.h"
  33
  34 #include "glibintl.h"
  35
  36 /**
  37  * SECTION:gcredentials
  38  * @short_description: An object containing credentials
  39  * @include: gio/gio.h
  40  *
  41  * The #GCredentials type is a reference-counted wrapper for native
  42  * credentials. This information is typically used for identifying,
  43  * authenticating and authorizing other processes.
  44  *
  45  * Some operating systems supports looking up the credentials of the
  46  * remote peer of a communication endpoint - see e.g.
  47  * g_socket_get_credentials().
  48  *
  49  * Some operating systems supports securely sending and receiving
  50  * credentials over a Unix Domain Socket, see
  51  * #GUnixCredentialsMessage, g_unix_connection_send_credentials() and
  52  * g_unix_connection_receive_credentials() for details.
  53  *
  54  * On Linux, the native credential type is a struct ucred - see the
  55  * unix(7) man page for details. This corresponds to
  56  * %G_CREDENTIALS_TYPE_LINUX_UCRED.
  57  *
  58  * On FreeBSD, Debian GNU/kFreeBSD, and GNU/Hurd, the native
  59  * credential type is a struct cmsgcred. This corresponds
  60  * to %G_CREDENTIALS_TYPE_FREEBSD_CMSGCRED.
  61  *
  62  * On OpenBSD, the native credential type is a struct sockpeercred.
  63  * This corresponds to %G_CREDENTIALS_TYPE_OPENBSD_SOCKPEERCRED.
  64  *
  65  * On Solaris (including OpenSolaris and its derivatives), the native
  66  * credential type is a ucred_t. This corresponds to
  67  * %G_CREDENTIALS_TYPE_SOLARIS_UCRED.
  68  */
  69
  70 /**
  71  * GCredentials:
  72  *
  73  * The #GCredentials structure contains only private data and
  74  * should only be accessed using the provided API.
  75  *
  76  * Since: 2.26
  77  */
  78 struct _GCredentials
  79 {
  80   /*< private >*/
  81   GObject parent_instance;
  82
  83 #if G_CREDENTIALS_USE_LINUX_UCRED
  84   struct ucred native;
  85 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
  86   struct cmsgcred native;
  87 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
  88   struct sockpeercred native;
  89 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
  90   ucred_t *native;
  91 #else
  92   #ifdef __GNUC__
  93   #warning Please add GCredentials support for your OS
  94   #endif
  95 #endif
  96 };
  97
  98 /**
  99  * GCredentialsClass:
 100  *
 101  * Class structure for #GCredentials.
 102  *
 103  * Since: 2.26
 104  */
 105 struct _GCredentialsClass
 106 {
 107   /*< private >*/
 108   GObjectClass parent_class;
 109 };
 110
 111 G_DEFINE_TYPE (GCredentials, g_credentials, G_TYPE_OBJECT);
 112
 113 static void
 114 g_credentials_finalize (GObject *object)
 115 {
 116 #if G_CREDENTIALS_USE_SOLARIS_UCRED
 117   GCredentials *credentials = G_CREDENTIALS (object);
 118
 119   ucred_free (credentials->native);
 120 #endif
 121
 122   if (G_OBJECT_CLASS (g_credentials_parent_class)->finalize != NULL)
 123     G_OBJECT_CLASS (g_credentials_parent_class)->finalize (object);
 124 }
 125
 126
 127 static void
 128 g_credentials_class_init (GCredentialsClass *klass)
 129 {
 130   GObjectClass *gobject_class;
 131
 132   gobject_class = G_OBJECT_CLASS (klass);
 133   gobject_class->finalize = g_credentials_finalize;
 134 }
 135
 136 static void
 137 g_credentials_init (GCredentials *credentials)
 138 {
 139 #if G_CREDENTIALS_USE_LINUX_UCRED
 140   credentials->native.pid = getpid ();
 141   credentials->native.uid = geteuid ();
 142   credentials->native.gid = getegid ();
 143 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 144   memset (&credentials->native, 0, sizeof (struct cmsgcred));
 145   credentials->native.cmcred_pid  = getpid ();
 146   credentials->native.cmcred_euid = geteuid ();
 147   credentials->native.cmcred_gid  = getegid ();
 148 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 149   credentials->native.pid = getpid ();
 150   credentials->native.uid = geteuid ();
 151   credentials->native.gid = getegid ();
 152 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 153   credentials->native = ucred_get (P_MYID);
 154 #endif
 155 }
 156
 157 /* ---------------------------------------------------------------------------------------------------- */
 158
 159 /**
 160  * g_credentials_new:
 161  *
 162  * Creates a new #GCredentials object with credentials matching the
 163  * the current process.
 164  *
 165  * Returns: A #GCredentials. Free with g_object_unref().
 166  *
 167  * Since: 2.26
 168  */
 169 GCredentials *
 170 g_credentials_new (void)
 171 {
 172   return g_object_new (G_TYPE_CREDENTIALS, NULL);
 173 }
 174
 175 /* ---------------------------------------------------------------------------------------------------- */
 176
 177 /**
 178  * g_credentials_to_string:
 179  * @credentials: A #GCredentials object.
 180  *
 181  * Creates a human-readable textual representation of @credentials
 182  * that can be used in logging and debug messages. The format of the
 183  * returned string may change in future GLib release.
 184  *
 185  * Returns: A string that should be freed with g_free().
 186  *
 187  * Since: 2.26
 188  */
 189 gchar *
 190 g_credentials_to_string (GCredentials *credentials)
 191 {
 192   GString *ret;
 193
 194   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), NULL);
 195
 196   ret = g_string_new ("GCredentials:");
 197 #if G_CREDENTIALS_USE_LINUX_UCRED
 198   g_string_append (ret, "linux-ucred:");
 199   if (credentials->native.pid != -1)
 200     g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.pid);
 201   if (credentials->native.uid != -1)
 202     g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.uid);
 203   if (credentials->native.gid != -1)
 204     g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.gid);
 205   if (ret->str[ret->len - 1] == ',')
 206     ret->str[ret->len - 1] = '\0';
 207 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 208   g_string_append (ret, "freebsd-cmsgcred:");
 209   if (credentials->native.cmcred_pid != -1)
 210     g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.cmcred_pid);
 211   if (credentials->native.cmcred_euid != -1)
 212     g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.cmcred_euid);
 213   if (credentials->native.cmcred_gid != -1)
 214     g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.cmcred_gid);
 215 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 216   g_string_append (ret, "openbsd-sockpeercred:");
 217   if (credentials->native.pid != -1)
 218     g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.pid);
 219   if (credentials->native.uid != -1)
 220     g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.uid);
 221   if (credentials->native.gid != -1)
 222     g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.gid);
 223   if (ret->str[ret->len - 1] == ',')
 224     ret->str[ret->len - 1] = '\0';
 225 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 226   g_string_append (ret, "solaris-ucred:");
 227   {
 228     id_t id;
 229     if ((id = ucred_getpid (credentials->native)) != -1)
 230       g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) id);
 231     if ((id = ucred_geteuid (credentials->native)) != -1)
 232       g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) id);
 233     if ((id = ucred_getegid (credentials->native)) != -1)
 234       g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) id);
 235     if (ret->str[ret->len - 1] == ',')
 236       ret->str[ret->len - 1] = '\0';
 237   }
 238 #else
 239   g_string_append (ret, "unknown");
 240 #endif
 241
 242   return g_string_free (ret, FALSE);
 243 }
 244
 245 /* ---------------------------------------------------------------------------------------------------- */
 246
 247 /**
 248  * g_credentials_is_same_user:
 249  * @credentials: A #GCredentials.
 250  * @other_credentials: A #GCredentials.
 251  * @error: Return location for error or %NULL.
 252  *
 253  * Checks if @credentials and @other_credentials is the same user.
 254  *
 255  * This operation can fail if #GCredentials is not supported on the
 256  * the OS.
 257  *
 258  * Returns: %TRUE if @credentials and @other_credentials has the same
 259  * user, %FALSE otherwise or if @error is set.
 260  *
 261  * Since: 2.26
 262  */
 263 gboolean
 264 g_credentials_is_same_user (GCredentials  *credentials,
 265                             GCredentials  *other_credentials,
 266                             GError       **error)
 267 {
 268   gboolean ret;
 269
 270   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), FALSE);
 271   g_return_val_if_fail (G_IS_CREDENTIALS (other_credentials), FALSE);
 272   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 273
 274   ret = FALSE;
 275 #if G_CREDENTIALS_USE_LINUX_UCRED
 276   if (credentials->native.uid == other_credentials->native.uid)
 277     ret = TRUE;
 278 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 279   if (credentials->native.cmcred_euid == other_credentials->native.cmcred_euid)
 280     ret = TRUE;
 281 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 282   if (credentials->native.uid == other_credentials->native.uid)
 283     ret = TRUE;
 284 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 285   if (ucred_geteuid (credentials->native) == ucred_geteuid (other_credentials->native))
 286     ret = TRUE;
 287 #else
 288   g_set_error_literal (error,
 289                        G_IO_ERROR,
 290                        G_IO_ERROR_NOT_SUPPORTED,
 291                        _("GCredentials is not implemented on this OS"));
 292 #endif
 293
 294   return ret;
 295 }
 296
 297 static gboolean
 298 credentials_native_type_check (GCredentialsType  requested_type,
 299                                const char       *op)
 300 {
 301   GEnumClass *enum_class;
 302   GEnumValue *requested;
 303 #if G_CREDENTIALS_SUPPORTED
 304   GEnumValue *supported;
 305 #endif
 306
 307 #if G_CREDENTIALS_SUPPORTED
 308   if (requested_type == G_CREDENTIALS_NATIVE_TYPE)
 309     return TRUE;
 310 #endif
 311
 312   enum_class = g_type_class_ref (g_credentials_type_get_type ());
 313   requested = g_enum_get_value (enum_class, requested_type);
 314
 315 #if G_CREDENTIALS_SUPPORTED
 316   supported = g_enum_get_value (enum_class, G_CREDENTIALS_NATIVE_TYPE);
 317   g_warning ("g_credentials_%s_native: Trying to %s credentials of type %s "
 318              "but only %s is supported on this platform.",
 319              op, op,
 320              requested ? requested->value_name : "(unknown)",
 321              supported->value_name);
 322 #else
 323   g_warning ("g_credentials_%s_native: Trying to %s credentials of type %s "
 324              "but there is no support for GCredentials on this platform.",
 325              op, op,
 326              requested ? requested->value_name : "(unknown)");
 327 #endif
 328
 329   g_type_class_unref (enum_class);
 330   return FALSE;
 331 }
 332
 333 /**
 334  * g_credentials_get_native: (skip)
 335  * @credentials: A #GCredentials.
 336  * @native_type: The type of native credentials to get.
 337  *
 338  * Gets a pointer to native credentials of type @native_type from
 339  * @credentials.
 340  *
 341  * It is a programming error (which will cause an warning to be
 342  * logged) to use this method if there is no #GCredentials support for
 343  * the OS or if @native_type isn't supported by the OS.
 344  *
 345  * Returns: The pointer to native credentials or %NULL if the
 346  * operation there is no #GCredentials support for the OS or if
 347  * @native_type isn't supported by the OS. Do not free the returned
 348  * data, it is owned by @credentials.
 349  *
 350  * Since: 2.26
 351  */
 352 gpointer
 353 g_credentials_get_native (GCredentials     *credentials,
 354                           GCredentialsType  native_type)
 355 {
 356   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), NULL);
 357
 358   if (!credentials_native_type_check (native_type, "get"))
 359     return NULL;
 360
 361 #if G_CREDENTIALS_USE_SOLARIS_UCRED
 362   return credentials->native;
 363 #elif G_CREDENTIALS_SUPPORTED
 364   return &credentials->native;
 365 #else
 366   g_assert_not_reached ();
 367 #endif
 368 }
 369
 370 /**
 371  * g_credentials_set_native:
 372  * @credentials: A #GCredentials.
 373  * @native_type: The type of native credentials to set.
 374  * @native: A pointer to native credentials.
 375  *
 376  * Copies the native credentials of type @native_type from @native
 377  * into @credentials.
 378  *
 379  * It is a programming error (which will cause an warning to be
 380  * logged) to use this method if there is no #GCredentials support for
 381  * the OS or if @native_type isn't supported by the OS.
 382  *
 383  * Since: 2.26
 384  */
 385 void
 386 g_credentials_set_native (GCredentials     *credentials,
 387                           GCredentialsType  native_type,
 388                           gpointer          native)
 389 {
 390   if (!credentials_native_type_check (native_type, "set"))
 391     return;
 392
 393 #if G_CREDENTIALS_USE_SOLARIS_UCRED
 394   memcpy (credentials->native, native, ucred_size ());
 395 #elif G_CREDENTIALS_SUPPORTED
 396   memcpy (&credentials->native, native, sizeof (credentials->native));
 397 #else
 398   g_assert_not_reached ();
 399 #endif
 400 }
 401
 402 /* ---------------------------------------------------------------------------------------------------- */
 403
 404 #ifdef G_OS_UNIX
 405 /**
 406  * g_credentials_get_unix_user:
 407  * @credentials: A #GCredentials
 408  * @error: Return location for error or %NULL.
 409  *
 410  * Tries to get the UNIX user identifier from @credentials. This
 411  * method is only available on UNIX platforms.
 412  *
 413  * This operation can fail if #GCredentials is not supported on the
 414  * OS or if the native credentials type does not contain information
 415  * about the UNIX user.
 416  *
 417  * Returns: The UNIX user identifier or -1 if @error is set.
 418  *
 419  * Since: 2.26
 420  */
 421 uid_t
 422 g_credentials_get_unix_user (GCredentials    *credentials,
 423                              GError         **error)
 424 {
 425   uid_t ret;
 426
 427   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), -1);
 428   g_return_val_if_fail (error == NULL || *error == NULL, -1);
 429
 430 #if G_CREDENTIALS_USE_LINUX_UCRED
 431   ret = credentials->native.uid;
 432 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 433   ret = credentials->native.cmcred_euid;
 434 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 435   ret = credentials->native.uid;
 436 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 437   ret = ucred_geteuid (credentials->native);
 438 #else
 439   ret = -1;
 440   g_set_error_literal (error,
 441                        G_IO_ERROR,
 442                        G_IO_ERROR_NOT_SUPPORTED,
 443                        _("There is no GCredentials support for your platform"));
 444 #endif
 445
 446   return ret;
 447 }
 448
 449 /**
 450  * g_credentials_get_unix_pid:
 451  * @credentials: A #GCredentials
 452  * @error: Return location for error or %NULL.
 453  *
 454  * Tries to get the UNIX process identifier from @credentials. This
 455  * method is only available on UNIX platforms.
 456  *
 457  * This operation can fail if #GCredentials is not supported on the
 458  * OS or if the native credentials type does not contain information
 459  * about the UNIX process ID.
 460  *
 461  * Returns: The UNIX process ID, or -1 if @error is set.
 462  *
 463  * Since: 2.36
 464  */
 465 pid_t
 466 g_credentials_get_unix_pid (GCredentials    *credentials,
 467                             GError         **error)
 468 {
 469   pid_t ret;
 470
 471   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), -1);
 472   g_return_val_if_fail (error == NULL || *error == NULL, -1);
 473
 474 #if G_CREDENTIALS_USE_LINUX_UCRED
 475   ret = credentials->native.pid;
 476 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 477   ret = credentials->native.cmcred_pid;
 478 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 479   ret = credentials->native.pid;
 480 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 481   ret = ucred_getpid (credentials->native);
 482 #else
 483   ret = -1;
 484   g_set_error_literal (error,
 485                        G_IO_ERROR,
 486                        G_IO_ERROR_NOT_SUPPORTED,
 487                        _("GCredentials does not contain a process ID on this OS"));
 488 #endif
 489
 490   return ret;
 491 }
 492
 493 /**
 494  * g_credentials_set_unix_user:
 495  * @credentials: A #GCredentials.
 496  * @uid: The UNIX user identifier to set.
 497  * @error: Return location for error or %NULL.
 498  *
 499  * Tries to set the UNIX user identifier on @credentials. This method
 500  * is only available on UNIX platforms.
 501  *
 502  * This operation can fail if #GCredentials is not supported on the
 503  * OS or if the native credentials type does not contain information
 504  * about the UNIX user. It can also fail if the OS does not allow the
 505  * use of "spoofed" credentials.
 506  *
 507  * Returns: %TRUE if @uid was set, %FALSE if error is set.
 508  *
 509  * Since: 2.26
 510  */
 511 gboolean
 512 g_credentials_set_unix_user (GCredentials    *credentials,
 513                              uid_t            uid,
 514                              GError         **error)
 515 {
 516   gboolean ret;
 517
 518   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), FALSE);
 519   g_return_val_if_fail (uid != -1, FALSE);
 520   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 521
 522   ret = FALSE;
 523 #if G_CREDENTIALS_USE_LINUX_UCRED
 524   credentials->native.uid = uid;
 525   ret = TRUE;
 526 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 527   credentials->native.cmcred_euid = uid;
 528   ret = TRUE;
 529 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 530   credentials->native.uid = uid;
 531   ret = TRUE;
 532 #elif !G_CREDENTIALS_SPOOFING_SUPPORTED
 533   g_set_error_literal (error,
 534                        G_IO_ERROR,
 535                        G_IO_ERROR_PERMISSION_DENIED,
 536                        _("Credentials spoofing is not possible on this OS"));
 537   ret = FALSE;
 538 #else
 539   g_set_error_literal (error,
 540                        G_IO_ERROR,
 541                        G_IO_ERROR_NOT_SUPPORTED,
 542                        _("GCredentials is not implemented on this OS"));
 543   ret = FALSE;
 544 #endif
 545
 546   return ret;
 547 }
 548
 549 #endif /* G_OS_UNIX */