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/* NetworkManager -- Network link manager
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Copyright (C) 2007 - 2013 Red Hat, Inc.
*/
#include "nm-default.h"
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include "nm-utils/nm-vpn-plugin-macros.h"
#include "nm-dhcp-helper-api.h"
/*****************************************************************************/
#if NM_MORE_LOGGING
#define _NMLOG_ENABLED(level) TRUE
#else
#define _NMLOG_ENABLED(level) ((level) <= LOG_ERR)
#endif
#define _NMLOG(always_enabled, level, ...) \
G_STMT_START { \
if ((always_enabled) || _NMLOG_ENABLED (level)) { \
GTimeVal _tv; \
\
g_get_current_time (&_tv); \
g_print ("nm-dhcp-helper[%ld] %-7s [%ld.%04ld] " _NM_UTILS_MACRO_FIRST (__VA_ARGS__) "\n", \
(long) getpid (), \
nm_utils_syslog_to_str (level), \
_tv.tv_sec, _tv.tv_usec / 100 \
_NM_UTILS_MACRO_REST (__VA_ARGS__)); \
} \
} G_STMT_END
#define _LOGD(...) _NMLOG(TRUE, LOG_INFO, __VA_ARGS__)
#define _LOGI(...) _NMLOG(TRUE, LOG_NOTICE, __VA_ARGS__)
#define _LOGW(...) _NMLOG(TRUE, LOG_WARNING, __VA_ARGS__)
#define _LOGE(...) _NMLOG(TRUE, LOG_ERR, __VA_ARGS__)
#define _LOGd(...) _NMLOG(FALSE, LOG_INFO, __VA_ARGS__)
#define _LOGi(...) _NMLOG(FALSE, LOG_NOTICE, __VA_ARGS__)
#define _LOGw(...) _NMLOG(FALSE, LOG_WARNING, __VA_ARGS__)
/*****************************************************************************/
static const char * ignore[] = {"PATH", "SHLVL", "_", "PWD", "dhc_dbus", NULL};
static GVariant *
build_signal_parameters (void)
{
char **item;
GVariantBuilder builder;
g_variant_builder_init (&builder, G_VARIANT_TYPE_VARDICT);
/* List environment and format for dbus dict */
for (item = environ; *item; item++) {
char *name, *val, **p;
/* Split on the = */
name = g_strdup (*item);
val = strchr (name, '=');
if (!val || val == name)
goto next;
*val++ = '\0';
/* Ignore non-DCHP-related environment variables */
for (p = (char **) ignore; *p; p++) {
if (strncmp (name, *p, strlen (*p)) == 0)
goto next;
}
/* Value passed as a byte array rather than a string, because there are
* no character encoding guarantees with DHCP, and D-Bus requires
* strings to be UTF-8.
*
* Note that we can't use g_variant_new_bytestring() here, because that
* includes the trailing '\0'. (??!?)
*/
g_variant_builder_add (&builder, "{sv}",
name,
g_variant_new_fixed_array (G_VARIANT_TYPE_BYTE,
val, strlen (val), 1));
next:
g_free (name);
}
return g_variant_ref_sink (g_variant_new ("(a{sv})", &builder));
}
static void
kill_pid (void)
{
const char *pid_str;
pid_t pid = 0;
pid_str = getenv ("pid");
if (pid_str)
pid = strtol (pid_str, NULL, 10);
if (pid) {
_LOGI ("a fatal error occurred, kill dhclient instance with pid %d", pid);
kill (pid, SIGTERM);
}
}
int
main (int argc, char *argv[])
{
gs_unref_object GDBusConnection *connection = NULL;
gs_free_error GError *error = NULL;
gs_unref_variant GVariant *parameters = NULL;
gs_unref_variant GVariant *result = NULL;
gboolean success = FALSE;
guint try_count = 0;
gint64 time_end;
/* FIXME: g_dbus_connection_new_for_address_sync() tries to connect to the socket in
* non-blocking mode, which can easily fail with EAGAIN, causing the creation of the
* socket to fail with "Could not connect: Resource temporarily unavailable".
*
* We should instead create the GIOStream ourself and block on connecting to
* the socket. */
connection = g_dbus_connection_new_for_address_sync ("unix:path=" NMRUNDIR "/private-dhcp",
G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT,
NULL, NULL, &error);
if (!connection) {
g_dbus_error_strip_remote_error (error);
_LOGE ("could not connect to NetworkManager D-Bus socket: %s",
error->message);
goto out;
}
parameters = build_signal_parameters ();
time_end = g_get_monotonic_time () + (200 * 1000L); /* retry for at most 200 milliseconds */
do_notify:
try_count++;
result = g_dbus_connection_call_sync (connection,
NULL,
NM_DHCP_HELPER_SERVER_OBJECT_PATH,
NM_DHCP_HELPER_SERVER_INTERFACE_NAME,
NM_DHCP_HELPER_SERVER_METHOD_NOTIFY,
parameters,
NULL,
G_DBUS_CALL_FLAGS_NONE,
1000,
NULL,
&error);
if (!result) {
gs_free char *s_err = NULL;
s_err = g_dbus_error_get_remote_error (error);
if (NM_IN_STRSET (s_err, "org.freedesktop.DBus.Error.UnknownMethod")) {
gint64 remaining_time = time_end - g_get_monotonic_time ();
/* I am not sure that a race can actually happen, as we register the object
* on the server side during GDBusServer:new-connection signal.
*
* However, there was also a race for subscribing to an event, so let's just
* do some retry. */
if (remaining_time > 0) {
_LOGi ("failure to call notify: %s (retry %u)", error->message, try_count);
g_usleep (NM_MIN (NM_CLAMP ((gint64) (100L * (1L << try_count)), 5000, 25000), remaining_time));
g_clear_error (&error);
goto do_notify;
}
}
_LOGW ("failure to call notify: %s (try signal via Event)", error->message);
g_clear_error (&error);
/* for backward compatibility, try to emit the signal. There is no stable
* API between the dhcp-helper and NetworkManager. However, while upgrading
* the NetworkManager package, a newer helper might want to notify an
* older server, which still uses the "Event". */
if (!g_dbus_connection_emit_signal (connection,
NULL,
"/",
NM_DHCP_CLIENT_DBUS_IFACE,
"Event",
parameters,
&error)) {
g_dbus_error_strip_remote_error (error);
_LOGE ("could not send DHCP Event signal: %s", error->message);
goto out;
}
/* We were able to send the asynchronous Event. Consider that a success. */
success = TRUE;
} else
success = TRUE;
if (!g_dbus_connection_flush_sync (connection, NULL, &error)) {
g_dbus_error_strip_remote_error (error);
_LOGE ("could not flush D-Bus connection: %s", error->message);
success = FALSE;
goto out;
}
out:
if (!success)
kill_pid ();
return success ? EXIT_SUCCESS : EXIT_FAILURE;
}
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