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, 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 <stdlib.h>
  26 #include <string.h>
  27
  28 #include <gobject/gvaluecollector.h>
  29
  30 #include "gcredentials.h"
  31 #include "gcredentialsprivate.h"
  32 #include "gnetworking.h"
  33 #include "gioerror.h"
  34 #include "gioenumtypes.h"
  35
  36 #include "glibintl.h"
  37
  38 /**
  39  * SECTION:gcredentials
  40  * @short_description: An object containing credentials
  41  * @include: gio/gio.h
  42  *
  43  * The #GCredentials type is a reference-counted wrapper for native
  44  * credentials. This information is typically used for identifying,
  45  * authenticating and authorizing other processes.
  46  *
  47  * Some operating systems supports looking up the credentials of the
  48  * remote peer of a communication endpoint - see e.g.
  49  * g_socket_get_credentials().
  50  *
  51  * Some operating systems supports securely sending and receiving
  52  * credentials over a Unix Domain Socket, see
  53  * #GUnixCredentialsMessage, g_unix_connection_send_credentials() and
  54  * g_unix_connection_receive_credentials() for details.
  55  *
  56  * On Linux, the native credential type is a <type>struct ucred</type>
  57  * - see the
  58  * <citerefentry><refentrytitle>unix</refentrytitle><manvolnum>7</manvolnum></citerefentry>
  59  * man page for details. This corresponds to
  60  * %G_CREDENTIALS_TYPE_LINUX_UCRED.
  61  *
  62  * On FreeBSD, Debian GNU/kFreeBSD, and GNU/Hurd, the native
  63  * credential type is a <type>struct cmsgcred</type>. This corresponds
  64  * to %G_CREDENTIALS_TYPE_FREEBSD_CMSGCRED.
  65  *
  66  * On OpenBSD, the native credential type is a <type>struct sockpeercred</type>.
  67  * This corresponds to %G_CREDENTIALS_TYPE_OPENBSD_SOCKPEERCRED.
  68  *
  69  * On Solaris (including OpenSolaris and its derivatives), the native
  70  * credential type is a <type>ucred_t</type>. This corresponds to
  71  * %G_CREDENTIALS_TYPE_SOLARIS_UCRED.
  72  */
  73
  74 /**
  75  * GCredentials:
  76  *
  77  * The #GCredentials structure contains only private data and
  78  * should only be accessed using the provided API.
  79  *
  80  * Since: 2.26
  81  */
  82 struct _GCredentials
  83 {
  84   /*< private >*/
  85   GObject parent_instance;
  86
  87 #if G_CREDENTIALS_USE_LINUX_UCRED
  88   struct ucred native;
  89 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
  90   struct cmsgcred native;
  91 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
  92   struct sockpeercred native;
  93 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
  94   ucred_t *native;
  95 #else
  96   #ifdef __GNUC__
  97   #warning Please add GCredentials support for your OS
  98   #endif
  99 #endif
 100 };
 101
 102 /**
 103  * GCredentialsClass:
 104  *
 105  * Class structure for #GCredentials.
 106  *
 107  * Since: 2.26
 108  */
 109 struct _GCredentialsClass
 110 {
 111   /*< private >*/
 112   GObjectClass parent_class;
 113 };
 114
 115 G_DEFINE_TYPE (GCredentials, g_credentials, G_TYPE_OBJECT);
 116
 117 static void
 118 g_credentials_finalize (GObject *object)
 119 {
 120 #if G_CREDENTIALS_USE_SOLARIS_UCRED
 121   GCredentials *credentials = G_CREDENTIALS (object);
 122
 123   ucred_free (credentials->native);
 124 #endif
 125
 126   if (G_OBJECT_CLASS (g_credentials_parent_class)->finalize != NULL)
 127     G_OBJECT_CLASS (g_credentials_parent_class)->finalize (object);
 128 }
 129
 130
 131 static void
 132 g_credentials_class_init (GCredentialsClass *klass)
 133 {
 134   GObjectClass *gobject_class;
 135
 136   gobject_class = G_OBJECT_CLASS (klass);
 137   gobject_class->finalize = g_credentials_finalize;
 138 }
 139
 140 static void
 141 g_credentials_init (GCredentials *credentials)
 142 {
 143 #if G_CREDENTIALS_USE_LINUX_UCRED
 144   credentials->native.pid = getpid ();
 145   credentials->native.uid = geteuid ();
 146   credentials->native.gid = getegid ();
 147 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 148   memset (&credentials->native, 0, sizeof (struct cmsgcred));
 149   credentials->native.cmcred_pid  = getpid ();
 150   credentials->native.cmcred_euid = geteuid ();
 151   credentials->native.cmcred_gid  = getegid ();
 152 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 153   credentials->native.pid = getpid ();
 154   credentials->native.uid = geteuid ();
 155   credentials->native.gid = getegid ();
 156 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 157   credentials->native = ucred_get (P_MYID);
 158 #endif
 159 }
 160
 161 /* ---------------------------------------------------------------------------------------------------- */
 162
 163 /**
 164  * g_credentials_new:
 165  *
 166  * Creates a new #GCredentials object with credentials matching the
 167  * the current process.
 168  *
 169  * Returns: A #GCredentials. Free with g_object_unref().
 170  *
 171  * Since: 2.26
 172  */
 173 GCredentials *
 174 g_credentials_new (void)
 175 {
 176   return g_object_new (G_TYPE_CREDENTIALS, NULL);
 177 }
 178
 179 /* ---------------------------------------------------------------------------------------------------- */
 180
 181 /**
 182  * g_credentials_to_string:
 183  * @credentials: A #GCredentials object.
 184  *
 185  * Creates a human-readable textual representation of @credentials
 186  * that can be used in logging and debug messages. The format of the
 187  * returned string may change in future GLib release.
 188  *
 189  * Returns: A string that should be freed with g_free().
 190  *
 191  * Since: 2.26
 192  */
 193 gchar *
 194 g_credentials_to_string (GCredentials *credentials)
 195 {
 196   GString *ret;
 197
 198   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), NULL);
 199
 200   ret = g_string_new ("GCredentials:");
 201 #if G_CREDENTIALS_USE_LINUX_UCRED
 202   g_string_append (ret, "linux-ucred:");
 203   if (credentials->native.pid != -1)
 204     g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.pid);
 205   if (credentials->native.uid != -1)
 206     g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.uid);
 207   if (credentials->native.gid != -1)
 208     g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.gid);
 209   if (ret->str[ret->len - 1] == ',')
 210     ret->str[ret->len - 1] = '\0';
 211 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 212   g_string_append (ret, "freebsd-cmsgcred:");
 213   if (credentials->native.cmcred_pid != -1)
 214     g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.cmcred_pid);
 215   if (credentials->native.cmcred_euid != -1)
 216     g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.cmcred_euid);
 217   if (credentials->native.cmcred_gid != -1)
 218     g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.cmcred_gid);
 219 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 220   g_string_append (ret, "openbsd-sockpeercred:");
 221   if (credentials->native.pid != -1)
 222     g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.pid);
 223   if (credentials->native.uid != -1)
 224     g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.uid);
 225   if (credentials->native.gid != -1)
 226     g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) credentials->native.gid);
 227   if (ret->str[ret->len - 1] == ',')
 228     ret->str[ret->len - 1] = '\0';
 229 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 230   g_string_append (ret, "solaris-ucred:");
 231   {
 232     id_t id;
 233     if ((id = ucred_getpid (credentials->native)) != -1)
 234       g_string_append_printf (ret, "pid=%" G_GINT64_FORMAT ",", (gint64) id);
 235     if ((id = ucred_geteuid (credentials->native)) != -1)
 236       g_string_append_printf (ret, "uid=%" G_GINT64_FORMAT ",", (gint64) id);
 237     if ((id = ucred_getegid (credentials->native)) != -1)
 238       g_string_append_printf (ret, "gid=%" G_GINT64_FORMAT ",", (gint64) id);
 239     if (ret->str[ret->len - 1] == ',')
 240       ret->str[ret->len - 1] = '\0';
 241   }
 242 #else
 243   g_string_append (ret, "unknown");
 244 #endif
 245
 246   return g_string_free (ret, FALSE);
 247 }
 248
 249 /* ---------------------------------------------------------------------------------------------------- */
 250
 251 /**
 252  * g_credentials_is_same_user:
 253  * @credentials: A #GCredentials.
 254  * @other_credentials: A #GCredentials.
 255  * @error: Return location for error or %NULL.
 256  *
 257  * Checks if @credentials and @other_credentials is the same user.
 258  *
 259  * This operation can fail if #GCredentials is not supported on the
 260  * the OS.
 261  *
 262  * Returns: %TRUE if @credentials and @other_credentials has the same
 263  * user, %FALSE otherwise or if @error is set.
 264  *
 265  * Since: 2.26
 266  */
 267 gboolean
 268 g_credentials_is_same_user (GCredentials  *credentials,
 269                             GCredentials  *other_credentials,
 270                             GError       **error)
 271 {
 272   gboolean ret;
 273
 274   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), FALSE);
 275   g_return_val_if_fail (G_IS_CREDENTIALS (other_credentials), FALSE);
 276   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 277
 278   ret = FALSE;
 279 #if G_CREDENTIALS_USE_LINUX_UCRED
 280   if (credentials->native.uid == other_credentials->native.uid)
 281     ret = TRUE;
 282 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 283   if (credentials->native.cmcred_euid == other_credentials->native.cmcred_euid)
 284     ret = TRUE;
 285 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 286   if (credentials->native.uid == other_credentials->native.uid)
 287     ret = TRUE;
 288 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 289   if (ucred_geteuid (credentials->native) == ucred_geteuid (other_credentials->native))
 290     ret = TRUE;
 291 #else
 292   g_set_error_literal (error,
 293                        G_IO_ERROR,
 294                        G_IO_ERROR_NOT_SUPPORTED,
 295                        _("GCredentials is not implemented on this OS"));
 296 #endif
 297
 298   return ret;
 299 }
 300
 301 static gboolean
 302 credentials_native_type_check (GCredentialsType  requested_type,
 303                                const char       *op)
 304 {
 305   GEnumClass *enum_class;
 306   GEnumValue *requested;
 307 #if G_CREDENTIALS_SUPPORTED
 308   GEnumValue *supported;
 309 #endif
 310
 311 #if G_CREDENTIALS_SUPPORTED
 312   if (requested_type == G_CREDENTIALS_NATIVE_TYPE)
 313     return TRUE;
 314 #endif
 315
 316   enum_class = g_type_class_ref (g_credentials_type_get_type ());
 317   requested = g_enum_get_value (enum_class, requested_type);
 318
 319 #if G_CREDENTIALS_SUPPORTED
 320   supported = g_enum_get_value (enum_class, G_CREDENTIALS_NATIVE_TYPE);
 321   g_warning ("g_credentials_%s_native: Trying to %s credentials of type %s "
 322              "but only %s is supported on this platform.",
 323              op, op,
 324              requested ? requested->value_name : "(unknown)",
 325              supported->value_name);
 326 #else
 327   g_warning ("g_credentials_%s_native: Trying to %s credentials of type %s "
 328              "but there is no support for GCredentials on this platform.",
 329              op, op,
 330              requested ? requested->value_name : "(unknown)");
 331 #endif
 332
 333   g_type_class_unref (enum_class);
 334   return FALSE;
 335 }
 336
 337 /**
 338  * g_credentials_get_native: (skip)
 339  * @credentials: A #GCredentials.
 340  * @native_type: The type of native credentials to get.
 341  *
 342  * Gets a pointer to native credentials of type @native_type from
 343  * @credentials.
 344  *
 345  * It is a programming error (which will cause an warning to be
 346  * logged) to use this method if there is no #GCredentials support for
 347  * the OS or if @native_type isn't supported by the OS.
 348  *
 349  * Returns: The pointer to native credentials or %NULL if the
 350  * operation there is no #GCredentials support for the OS or if
 351  * @native_type isn't supported by the OS. Do not free the returned
 352  * data, it is owned by @credentials.
 353  *
 354  * Since: 2.26
 355  */
 356 gpointer
 357 g_credentials_get_native (GCredentials     *credentials,
 358                           GCredentialsType  native_type)
 359 {
 360   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), NULL);
 361
 362   if (!credentials_native_type_check (native_type, "get"))
 363     return NULL;
 364
 365 #if G_CREDENTIALS_USE_SOLARIS_UCRED
 366   return credentials->native;
 367 #elif G_CREDENTIALS_SUPPORTED
 368   return &credentials->native;
 369 #else
 370   g_assert_not_reached ();
 371 #endif
 372 }
 373
 374 /**
 375  * g_credentials_set_native:
 376  * @credentials: A #GCredentials.
 377  * @native_type: The type of native credentials to set.
 378  * @native: A pointer to native credentials.
 379  *
 380  * Copies the native credentials of type @native_type from @native
 381  * into @credentials.
 382  *
 383  * It is a programming error (which will cause an warning to be
 384  * logged) to use this method if there is no #GCredentials support for
 385  * the OS or if @native_type isn't supported by the OS.
 386  *
 387  * Since: 2.26
 388  */
 389 void
 390 g_credentials_set_native (GCredentials     *credentials,
 391                           GCredentialsType  native_type,
 392                           gpointer          native)
 393 {
 394   if (!credentials_native_type_check (native_type, "set"))
 395     return;
 396
 397 #if G_CREDENTIALS_USE_SOLARIS_UCRED
 398   memcpy (credentials->native, native, ucred_size ());
 399 #elif G_CREDENTIALS_SUPPORTED
 400   memcpy (&credentials->native, native, sizeof (credentials->native));
 401 #else
 402   g_assert_not_reached ();
 403 #endif
 404 }
 405
 406 /* ---------------------------------------------------------------------------------------------------- */
 407
 408 #ifdef G_OS_UNIX
 409 /**
 410  * g_credentials_get_unix_user:
 411  * @credentials: A #GCredentials
 412  * @error: Return location for error or %NULL.
 413  *
 414  * Tries to get the UNIX user identifier from @credentials. This
 415  * method is only available on UNIX platforms.
 416  *
 417  * This operation can fail if #GCredentials is not supported on the
 418  * OS or if the native credentials type does not contain information
 419  * about the UNIX user.
 420  *
 421  * Returns: The UNIX user identifier or -1 if @error is set.
 422  *
 423  * Since: 2.26
 424  */
 425 uid_t
 426 g_credentials_get_unix_user (GCredentials    *credentials,
 427                              GError         **error)
 428 {
 429   uid_t ret;
 430
 431   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), -1);
 432   g_return_val_if_fail (error == NULL || *error == NULL, -1);
 433
 434 #if G_CREDENTIALS_USE_LINUX_UCRED
 435   ret = credentials->native.uid;
 436 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 437   ret = credentials->native.cmcred_euid;
 438 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 439   ret = credentials->native.uid;
 440 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 441   ret = ucred_geteuid (credentials->native);
 442 #else
 443   ret = -1;
 444   g_set_error_literal (error,
 445                        G_IO_ERROR,
 446                        G_IO_ERROR_NOT_SUPPORTED,
 447                        _("There is no GCredentials support for your platform"));
 448 #endif
 449
 450   return ret;
 451 }
 452
 453 /**
 454  * g_credentials_get_unix_pid:
 455  * @credentials: A #GCredentials
 456  * @error: Return location for error or %NULL.
 457  *
 458  * Tries to get the UNIX process identifier from @credentials. This
 459  * method is only available on UNIX platforms.
 460  *
 461  * This operation can fail if #GCredentials is not supported on the
 462  * OS or if the native credentials type does not contain information
 463  * about the UNIX process ID.
 464  *
 465  * Returns: The UNIX process ID, or -1 if @error is set.
 466  *
 467  * Since: 2.36
 468  */
 469 pid_t
 470 g_credentials_get_unix_pid (GCredentials    *credentials,
 471                             GError         **error)
 472 {
 473   pid_t ret;
 474
 475   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), -1);
 476   g_return_val_if_fail (error == NULL || *error == NULL, -1);
 477
 478 #if G_CREDENTIALS_USE_LINUX_UCRED
 479   ret = credentials->native.pid;
 480 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 481   ret = credentials->native.cmcred_pid;
 482 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 483   ret = credentials->native.pid;
 484 #elif G_CREDENTIALS_USE_SOLARIS_UCRED
 485   ret = ucred_getpid (credentials->native);
 486 #else
 487   ret = -1;
 488   g_set_error_literal (error,
 489                        G_IO_ERROR,
 490                        G_IO_ERROR_NOT_SUPPORTED,
 491                        _("GCredentials does not contain a process ID on this OS"));
 492 #endif
 493
 494   return ret;
 495 }
 496
 497 /**
 498  * g_credentials_set_unix_user:
 499  * @credentials: A #GCredentials.
 500  * @uid: The UNIX user identifier to set.
 501  * @error: Return location for error or %NULL.
 502  *
 503  * Tries to set the UNIX user identifier on @credentials. This method
 504  * is only available on UNIX platforms.
 505  *
 506  * This operation can fail if #GCredentials is not supported on the
 507  * OS or if the native credentials type does not contain information
 508  * about the UNIX user. It can also fail if the OS does not allow the
 509  * use of "spoofed" credentials.
 510  *
 511  * Returns: %TRUE if @uid was set, %FALSE if error is set.
 512  *
 513  * Since: 2.26
 514  */
 515 gboolean
 516 g_credentials_set_unix_user (GCredentials    *credentials,
 517                              uid_t            uid,
 518                              GError         **error)
 519 {
 520   gboolean ret;
 521
 522   g_return_val_if_fail (G_IS_CREDENTIALS (credentials), FALSE);
 523   g_return_val_if_fail (uid != -1, FALSE);
 524   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 525
 526   ret = FALSE;
 527 #if G_CREDENTIALS_USE_LINUX_UCRED
 528   credentials->native.uid = uid;
 529   ret = TRUE;
 530 #elif G_CREDENTIALS_USE_FREEBSD_CMSGCRED
 531   credentials->native.cmcred_euid = uid;
 532   ret = TRUE;
 533 #elif G_CREDENTIALS_USE_OPENBSD_SOCKPEERCRED
 534   credentials->native.uid = uid;
 535   ret = TRUE;
 536 #elif !G_CREDENTIALS_SPOOFING_SUPPORTED
 537   g_set_error_literal (error,
 538                        G_IO_ERROR,
 539                        G_IO_ERROR_PERMISSION_DENIED,
 540                        _("Credentials spoofing is not possible on this OS"));
 541   ret = FALSE;
 542 #else
 543   g_set_error_literal (error,
 544                        G_IO_ERROR,
 545                        G_IO_ERROR_NOT_SUPPORTED,
 546                        _("GCredentials is not implemented on this OS"));
 547   ret = FALSE;
 548 #endif
 549
 550   return ret;
 551 }
 552
 553 #endif /* G_OS_UNIX */