D-Bus  1.10.24
dbus-server-unix.c
1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-server-unix.c Server implementation for Unix network protocols.
3  *
4  * Copyright (C) 2002, 2003, 2004 Red Hat Inc.
5  *
6  * Licensed under the Academic Free License version 2.1
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  *
22  */
23 
24 #include <config.h>
25 #include "dbus-internals.h"
26 #include "dbus-server-unix.h"
27 #include "dbus-server-socket.h"
28 #include "dbus-server-launchd.h"
29 #include "dbus-transport-unix.h"
30 #include "dbus-connection-internal.h"
31 #include "dbus-sysdeps-unix.h"
32 #include "dbus-string.h"
33 
53 DBusServerListenResult
55  DBusServer **server_p,
56  DBusError *error)
57 {
58  const char *method;
59 
60  *server_p = NULL;
61 
62  method = dbus_address_entry_get_method (entry);
63 
64  if (strcmp (method, "unix") == 0)
65  {
66  const char *path = dbus_address_entry_get_value (entry, "path");
67  const char *tmpdir = dbus_address_entry_get_value (entry, "tmpdir");
68  const char *abstract = dbus_address_entry_get_value (entry, "abstract");
69  const char *runtime = dbus_address_entry_get_value (entry, "runtime");
70  int mutually_exclusive_modes = 0;
71 
72  mutually_exclusive_modes = (path != NULL) + (tmpdir != NULL) +
73  (abstract != NULL) + (runtime != NULL);
74 
75  if (mutually_exclusive_modes < 1)
76  {
77  _dbus_set_bad_address(error, "unix",
78  "path or tmpdir or abstract or runtime",
79  NULL);
80  return DBUS_SERVER_LISTEN_BAD_ADDRESS;
81  }
82 
83  if (mutually_exclusive_modes > 1)
84  {
86  "cannot specify two of \"path\", \"tmpdir\", \"abstract\" and \"runtime\" at the same time");
87  return DBUS_SERVER_LISTEN_BAD_ADDRESS;
88  }
89 
90  if (runtime != NULL)
91  {
92  DBusString full_path;
93  DBusString filename;
94  const char *runtimedir;
95 
96  if (strcmp (runtime, "yes") != 0)
97  {
99  "if given, the only value allowed for \"runtime\" is \"yes\"");
100  return DBUS_SERVER_LISTEN_BAD_ADDRESS;
101  }
102 
103  runtimedir = _dbus_getenv ("XDG_RUNTIME_DIR");
104 
105  if (runtimedir == NULL)
106  {
107  dbus_set_error (error,
108  DBUS_ERROR_NOT_SUPPORTED, "\"XDG_RUNTIME_DIR\" is not set");
109  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
110  }
111 
112  _dbus_string_init_const (&filename, "bus");
113 
114  if (!_dbus_string_init (&full_path))
115  {
116  _DBUS_SET_OOM (error);
117  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
118  }
119 
120  if (!_dbus_string_append (&full_path, runtimedir) ||
121  !_dbus_concat_dir_and_file (&full_path, &filename))
122  {
123  _dbus_string_free (&full_path);
124  _DBUS_SET_OOM (error);
125  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
126  }
127 
128  /* We can safely use filesystem sockets in the runtime directory,
129  * and they are preferred because they can be bind-mounted between
130  * Linux containers. */
132  _dbus_string_get_const_data (&full_path),
133  FALSE, error);
134 
135  _dbus_string_free (&full_path);
136  }
137  else if (tmpdir != NULL)
138  {
139  DBusString full_path;
140  DBusString filename;
141 
142  if (!_dbus_string_init (&full_path))
143  {
145  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
146  }
147 
148  if (!_dbus_string_init (&filename))
149  {
150  _dbus_string_free (&full_path);
152  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
153  }
154 
155  if (!_dbus_string_append (&filename, "dbus-"))
156  {
157  _dbus_string_free (&full_path);
158  _dbus_string_free (&filename);
160  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
161  }
162 
163  if (!_dbus_generate_random_ascii (&filename, 10, error))
164  {
165  _dbus_string_free (&full_path);
166  _dbus_string_free (&filename);
167  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
168  }
169 
170  if (!_dbus_string_append (&full_path, tmpdir) ||
171  !_dbus_concat_dir_and_file (&full_path, &filename))
172  {
173  _dbus_string_free (&full_path);
174  _dbus_string_free (&filename);
176  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
177  }
178 
179  /* Always use abstract namespace if possible with tmpdir */
180 
181  *server_p =
182  _dbus_server_new_for_domain_socket (_dbus_string_get_const_data (&full_path),
183 #ifdef HAVE_ABSTRACT_SOCKETS
184  TRUE,
185 #else
186  FALSE,
187 #endif
188  error);
189 
190  _dbus_string_free (&full_path);
191  _dbus_string_free (&filename);
192  }
193  else
194  {
195  if (path)
196  *server_p = _dbus_server_new_for_domain_socket (path, FALSE, error);
197  else
198  *server_p = _dbus_server_new_for_domain_socket (abstract, TRUE, error);
199  }
200 
201  if (*server_p != NULL)
202  {
203  _DBUS_ASSERT_ERROR_IS_CLEAR(error);
204  return DBUS_SERVER_LISTEN_OK;
205  }
206  else
207  {
208  _DBUS_ASSERT_ERROR_IS_SET(error);
209  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
210  }
211  }
212  else if (strcmp (method, "systemd") == 0)
213  {
214  int i, n;
215  DBusSocket *fds;
216  DBusString address;
217 
218  n = _dbus_listen_systemd_sockets (&fds, error);
219  if (n < 0)
220  {
221  _DBUS_ASSERT_ERROR_IS_SET (error);
222  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
223  }
224 
225  if (!_dbus_string_init (&address))
226  goto systemd_oom;
227 
228  for (i = 0; i < n; i++)
229  {
230  if (i > 0)
231  {
232  if (!_dbus_string_append (&address, ";"))
233  goto systemd_oom;
234  }
235  if (!_dbus_append_address_from_socket (fds[i], &address, error))
236  goto systemd_err;
237  }
238 
239  *server_p = _dbus_server_new_for_socket (fds, n, &address, NULL, error);
240  if (*server_p == NULL)
241  goto systemd_err;
242 
243  dbus_free (fds);
244 
245  return DBUS_SERVER_LISTEN_OK;
246 
247  systemd_oom:
248  _DBUS_SET_OOM (error);
249  systemd_err:
250  for (i = 0; i < n; i++)
251  {
252  _dbus_close_socket (fds[i], NULL);
253  }
254  dbus_free (fds);
255  _dbus_string_free (&address);
256 
257  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
258  }
259 #ifdef DBUS_ENABLE_LAUNCHD
260  else if (strcmp (method, "launchd") == 0)
261  {
262  const char *launchd_env_var = dbus_address_entry_get_value (entry, "env");
263  if (launchd_env_var == NULL)
264  {
265  _dbus_set_bad_address (error, "launchd", "env", NULL);
266  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
267  }
268  *server_p = _dbus_server_new_for_launchd (launchd_env_var, error);
269 
270  if (*server_p != NULL)
271  {
272  _DBUS_ASSERT_ERROR_IS_CLEAR(error);
273  return DBUS_SERVER_LISTEN_OK;
274  }
275  else
276  {
277  _DBUS_ASSERT_ERROR_IS_SET(error);
278  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
279  }
280  }
281 #endif
282  else
283  {
284  /* If we don't handle the method, we return NULL with the
285  * error unset
286  */
287  _DBUS_ASSERT_ERROR_IS_CLEAR(error);
288  return DBUS_SERVER_LISTEN_NOT_HANDLED;
289  }
290 }
291 
300 DBusServer*
302  dbus_bool_t abstract,
303  DBusError *error)
304 {
305  DBusServer *server;
306  DBusSocket listen_fd;
307  DBusString address;
308  char *path_copy;
309  DBusString path_str;
310 
311  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
312 
313  if (!_dbus_string_init (&address))
314  {
316  return NULL;
317  }
318 
319  _dbus_string_init_const (&path_str, path);
320  if ((abstract &&
321  !_dbus_string_append (&address, "unix:abstract=")) ||
322  (!abstract &&
323  !_dbus_string_append (&address, "unix:path=")) ||
324  !_dbus_address_append_escaped (&address, &path_str))
325  {
327  goto failed_0;
328  }
329 
330  if (abstract)
331  {
332  path_copy = NULL;
333  }
334  else
335  {
336  path_copy = _dbus_strdup (path);
337  if (path_copy == NULL)
338  {
340  goto failed_0;
341  }
342  }
343 
344  listen_fd.fd = _dbus_listen_unix_socket (path, abstract, error);
345 
346  if (listen_fd.fd < 0)
347  {
348  _DBUS_ASSERT_ERROR_IS_SET (error);
349  goto failed_1;
350  }
351 
352  server = _dbus_server_new_for_socket (&listen_fd, 1, &address, 0, error);
353  if (server == NULL)
354  {
355  goto failed_2;
356  }
357 
358  if (path_copy != NULL)
359  _dbus_server_socket_own_filename(server, path_copy);
360 
361  _dbus_string_free (&address);
362 
363  return server;
364 
365  failed_2:
366  _dbus_close_socket (listen_fd, NULL);
367  failed_1:
368  dbus_free (path_copy);
369  failed_0:
370  _dbus_string_free (&address);
371 
372  return NULL;
373 }
374 
dbus_bool_t _dbus_string_append(DBusString *str, const char *buffer)
Appends a nul-terminated C-style string to a DBusString.
Definition: dbus-string.c:935
#define NULL
A null pointer, defined appropriately for C or C++.
void dbus_free(void *memory)
Frees a block of memory previously allocated by dbus_malloc() or dbus_malloc0().
Definition: dbus-memory.c:701
DBusServer * _dbus_server_new_for_launchd(const char *launchd_env_var, DBusError *error)
Creates a new server from launchd.
#define DBUS_ERROR_NOT_SUPPORTED
Requested operation isn&#39;t supported (like ENOSYS on UNIX).
Internals of DBusServer object.
dbus_bool_t _dbus_append_address_from_socket(DBusSocket fd, DBusString *address, DBusError *error)
Read the address from the socket and append it to the string.
const char * dbus_address_entry_get_method(DBusAddressEntry *entry)
Returns the method string of an address entry.
Definition: dbus-address.c:227
dbus_bool_t _dbus_concat_dir_and_file(DBusString *dir, const DBusString *next_component)
Appends the given filename to the given directory.
dbus_bool_t _dbus_string_init(DBusString *str)
Initializes a string.
Definition: dbus-string.c:175
DBusServerListenResult _dbus_server_listen_platform_specific(DBusAddressEntry *entry, DBusServer **server_p, DBusError *error)
Tries to interpret the address entry in a platform-specific way, creating a platform-specific server ...
dbus_bool_t _dbus_close_socket(DBusSocket fd, DBusError *error)
Closes a socket.
DBusServer * _dbus_server_new_for_socket(DBusSocket *fds, int n_fds, const DBusString *address, DBusNonceFile *noncefile, DBusError *error)
Creates a new server listening on the given file descriptor.
Socket interface.
Definition: dbus-sysdeps.h:148
const char * dbus_address_entry_get_value(DBusAddressEntry *entry, const char *key)
Returns a value from a key of an entry.
Definition: dbus-address.c:244
dbus_uint32_t dbus_bool_t
A boolean, valid values are TRUE and FALSE.
Definition: dbus-types.h:35
void _dbus_string_init_const(DBusString *str, const char *value)
Initializes a constant string.
Definition: dbus-string.c:190
dbus_bool_t _dbus_generate_random_ascii(DBusString *str, int n_bytes, DBusError *error)
Generates the given number of random bytes, where the bytes are chosen from the alphanumeric ASCII su...
Definition: dbus-sysdeps.c:550
void _dbus_server_socket_own_filename(DBusServer *server, char *filename)
This is a bad hack since it&#39;s really unix domain socket specific.
int _dbus_listen_systemd_sockets(DBusSocket **fds, DBusError *error)
Acquires one or more sockets passed in from systemd.
Internals of DBusAddressEntry.
Definition: dbus-address.c:43
void _dbus_set_bad_address(DBusError *error, const char *address_problem_type, const char *address_problem_field, const char *address_problem_other)
Sets DBUS_ERROR_BAD_ADDRESS.
Definition: dbus-address.c:65
Object representing an exception.
Definition: dbus-errors.h:48
dbus_bool_t _dbus_address_append_escaped(DBusString *escaped, const DBusString *unescaped)
Appends an escaped version of one string to another string, using the D-Bus address escaping mechanis...
Definition: dbus-address.c:104
void dbus_set_error(DBusError *error, const char *name, const char *format,...)
Assigns an error name and message to a DBusError.
Definition: dbus-errors.c:354
void _dbus_string_free(DBusString *str)
Frees a string created by _dbus_string_init().
Definition: dbus-string.c:259
#define TRUE
Expands to &quot;1&quot;.
DBusServer * _dbus_server_new_for_domain_socket(const char *path, dbus_bool_t abstract, DBusError *error)
Creates a new server listening on the given Unix domain socket.
#define DBUS_ERROR_NO_MEMORY
There was not enough memory to complete an operation.
#define FALSE
Expands to &quot;0&quot;.
char * _dbus_strdup(const char *str)
Duplicates a string.
const char * _dbus_getenv(const char *varname)
Wrapper for getenv().
Definition: dbus-sysdeps.c:185
int _dbus_listen_unix_socket(const char *path, dbus_bool_t abstract, DBusError *error)
Creates a socket and binds it to the given path, then listens on the socket.