diff options
Diffstat (limited to 'dbus/dbus-sysdeps.c')
| -rw-r--r-- | dbus/dbus-sysdeps.c | 91 |
1 files changed, 65 insertions, 26 deletions
diff --git a/dbus/dbus-sysdeps.c b/dbus/dbus-sysdeps.c index ab79a722..35900d70 100644 --- a/dbus/dbus-sysdeps.c +++ b/dbus/dbus-sysdeps.c @@ -373,13 +373,19 @@ _dbus_write_two (int fd, * Creates a socket and connects it to the UNIX domain socket at the * given path. The connection fd is returned, and is set up as * nonblocking. + * + * Uses abstract sockets instead of filesystem-linked sockets if + * requested (it's possible only on Linux; see "man 7 unix" on Linux). + * On non-Linux abstract socket usage always fails. * * @param path the path to UNIX domain socket + * @param abstract #TRUE to use abstract namespace * @param error return location for error code * @returns connection file descriptor or -1 on error */ int _dbus_connect_unix_socket (const char *path, + dbus_bool_t abstract, DBusError *error) { int fd; @@ -401,7 +407,23 @@ _dbus_connect_unix_socket (const char *path, _DBUS_ZERO (addr); addr.sun_family = AF_UNIX; - strncpy (addr.sun_path, path, _DBUS_MAX_SUN_PATH_LENGTH - 1); + + if (abstract) + { +#ifdef HAVE_ABSTRACT_SOCKETS + addr.sun_path[0] = '\0'; /* this is what says "use abstract" */ + strncpy (&addr.sun_path[1], path, _DBUS_MAX_SUN_PATH_LENGTH - 2); +#else /* HAVE_ABSTRACT_SOCKETS */ + dbus_set_error (error, DBUS_ERROR_NOT_SUPPORTED, + "Operating system does not support abstract socket namespace\n"); + close (fd); + return -1; +#endif /* ! HAVE_ABSTRACT_SOCKETS */ + } + else + { + strncpy (addr.sun_path, path, _DBUS_MAX_SUN_PATH_LENGTH - 1); + } if (connect (fd, (struct sockaddr*) &addr, sizeof (addr)) < 0) { @@ -434,18 +456,19 @@ _dbus_connect_unix_socket (const char *path, * then listens on the socket. The socket is * set to be nonblocking. * - * @todo we'd like to be able to use the abstract namespace on linux - * (see "man 7 unix"). The question is whether to silently move all - * paths into that namespace if we can (I think that's best) or to - * require it to be specified explicitly in the dbus address. Also, - * need to sort out how to check for abstract namespace support. + * Uses abstract sockets instead of filesystem-linked + * sockets if requested (it's possible only on Linux; + * see "man 7 unix" on Linux). + * On non-Linux abstract socket usage always fails. * * @param path the socket name + * @param abstract #TRUE to use abstract namespace * @param error return location for errors * @returns the listening file descriptor or -1 on error */ int _dbus_listen_unix_socket (const char *path, + dbus_bool_t abstract, DBusError *error) { int listen_fd; @@ -463,27 +486,43 @@ _dbus_listen_unix_socket (const char *path, return -1; } - /* FIXME discussed security implications of this with Nalin, - * and we couldn't think of where it would kick our ass, but - * it still seems a bit sucky. It also has non-security suckage; - * really we'd prefer to exit if the socket is already in use. - * But there doesn't seem to be a good way to do this. - * - * Just to be extra careful, I threw in the stat() - clearly - * the stat() can't *fix* any security issue, but it at least - * avoids inadvertent/accidental data loss. - */ - { - struct stat sb; - - if (stat (path, &sb) == 0 && - S_ISSOCK (sb.st_mode)) - unlink (path); - } - _DBUS_ZERO (addr); addr.sun_family = AF_UNIX; - strncpy (addr.sun_path, path, _DBUS_MAX_SUN_PATH_LENGTH - 1); + + if (abstract) + { +#ifdef HAVE_ABSTRACT_SOCKETS + addr.sun_path[0] = '\0'; /* this is what says "use abstract" */ + strncpy (&addr.sun_path[1], path, _DBUS_MAX_SUN_PATH_LENGTH - 2); +#else /* HAVE_ABSTRACT_SOCKETS */ + dbus_set_error (error, DBUS_ERROR_NOT_SUPPORTED, + "Operating system does not support abstract socket namespace\n"); + close (listen_fd); + return -1; +#endif /* ! HAVE_ABSTRACT_SOCKETS */ + } + else + { + /* FIXME discussed security implications of this with Nalin, + * and we couldn't think of where it would kick our ass, but + * it still seems a bit sucky. It also has non-security suckage; + * really we'd prefer to exit if the socket is already in use. + * But there doesn't seem to be a good way to do this. + * + * Just to be extra careful, I threw in the stat() - clearly + * the stat() can't *fix* any security issue, but it at least + * avoids inadvertent/accidental data loss. + */ + { + struct stat sb; + + if (stat (path, &sb) == 0 && + S_ISSOCK (sb.st_mode)) + unlink (path); + } + + strncpy (addr.sun_path, path, _DBUS_MAX_SUN_PATH_LENGTH - 1); + } if (bind (listen_fd, (struct sockaddr*) &addr, SUN_LEN (&addr)) < 0) { @@ -513,7 +552,7 @@ _dbus_listen_unix_socket (const char *path, /* Try opening up the permissions, but if we can't, just go ahead * and continue, maybe it will be good enough. */ - if (chmod (path, 0777) < 0) + if (!abstract && chmod (path, 0777) < 0) _dbus_warn ("Could not set mode 0777 on socket %s\n", path); |