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-rw-r--r--src/dns-manager/nm-dns-dnsmasq.c370
1 files changed, 370 insertions, 0 deletions
diff --git a/src/dns-manager/nm-dns-dnsmasq.c b/src/dns-manager/nm-dns-dnsmasq.c
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index 0000000000..254e2ffbb6
--- /dev/null
+++ b/src/dns-manager/nm-dns-dnsmasq.c
@@ -0,0 +1,370 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
+/*
+ * Copyright (C) 2010 Dan Williams <dcbw@redhat.com>
+ *
+ * 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, 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.
+ *
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <arpa/inet.h>
+#include <sys/stat.h>
+
+#include <glib.h>
+#include <glib/gi18n.h>
+
+#include "nm-dns-dnsmasq.h"
+#include "nm-logging.h"
+#include "nm-ip4-config.h"
+#include "nm-ip6-config.h"
+
+G_DEFINE_TYPE (NMDnsDnsmasq, nm_dns_dnsmasq, NM_TYPE_DNS_PLUGIN)
+
+#define NM_DNS_DNSMASQ_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), NM_TYPE_DNS_DNSMASQ, NMDnsDnsmasqPrivate))
+
+#define PIDFILE LOCALSTATEDIR "/run/nm-dns-dnsmasq.pid"
+#define CONFFILE LOCALSTATEDIR "/run/nm-dns-dnsmasq.conf"
+
+typedef struct {
+ guint32 foo;
+} NMDnsDnsmasqPrivate;
+
+/*******************************************/
+
+static inline const char *
+find_dnsmasq (void)
+{
+ static const char *paths[] = {
+ "/usr/local/sbin/dnsmasq",
+ "/usr/sbin/dnsmasq",
+ "/sbin/dnsmasq",
+ NULL
+ };
+ const char **binary = paths;
+
+ while (*binary != NULL) {
+ if (g_file_test (*binary, G_FILE_TEST_EXISTS))
+ return *binary;
+ binary++;
+ }
+ return NULL;
+}
+
+static gboolean
+add_ip4_config (GString *str, NMIP4Config *ip4, gboolean split)
+{
+ char buf[INET_ADDRSTRLEN + 1];
+ struct in_addr addr;
+ int n, i;
+ gboolean added = FALSE;
+
+ if (split) {
+ /* FIXME: it appears that dnsmasq can only handle one nameserver
+ * per domain (at the manpage seems to indicate that) so only use
+ * the first nameserver here.
+ */
+ addr.s_addr = nm_ip4_config_get_nameserver (ip4, 0);
+ memset (&buf[0], 0, sizeof (buf));
+ if (!inet_ntop (AF_INET, &addr, buf, sizeof (buf)))
+ return FALSE;
+
+ /* searches are preferred over domains */
+ n = nm_ip4_config_get_num_searches (ip4);
+ for (i = 0; i < n; i++) {
+ g_string_append_printf (str, "server=/%s/%s\n",
+ nm_ip4_config_get_search (ip4, i),
+ buf);
+ added = TRUE;
+ }
+
+ if (n == 0) {
+ /* If not searches, use any domains */
+ n = nm_ip4_config_get_num_domains (ip4);
+ for (i = 0; i < n; i++) {
+ g_string_append_printf (str, "server=/%s/%s\n",
+ nm_ip4_config_get_domain (ip4, i),
+ buf);
+ added = TRUE;
+ }
+ }
+ }
+
+ /* If no searches or domains, just add the namservers */
+ if (!added) {
+ n = nm_ip4_config_get_num_nameservers (ip4);
+ for (i = 0; i < n; i++) {
+ memset (&buf[0], 0, sizeof (buf));
+ addr.s_addr = nm_ip4_config_get_nameserver (ip4, i);
+ if (inet_ntop (AF_INET, &addr, buf, sizeof (buf)))
+ g_string_append_printf (str, "server=%s\n", buf);
+ }
+ }
+
+ return TRUE;
+}
+
+static gboolean
+ip6_addr_to_string (const struct in6_addr *addr, char *buf, size_t buflen)
+{
+ memset (buf, 0, buflen);
+
+ /* inet_ntop is probably supposed to do this for us, but it doesn't */
+ if (IN6_IS_ADDR_V4MAPPED (addr))
+ return !!inet_ntop (AF_INET, &(addr->s6_addr32[3]), buf, buflen);
+
+ return !!inet_ntop (AF_INET6, addr, buf, buflen);
+}
+
+static gboolean
+add_ip6_config (GString *str, NMIP6Config *ip6, gboolean split)
+{
+ char buf[INET6_ADDRSTRLEN + 1];
+ const struct in6_addr *addr;
+ int n, i;
+ gboolean added = FALSE;
+
+ if (split) {
+ /* FIXME: it appears that dnsmasq can only handle one nameserver
+ * per domain (at the manpage seems to indicate that) so only use
+ * the first nameserver here.
+ */
+ addr = nm_ip6_config_get_nameserver (ip6, 0);
+ if (!ip6_addr_to_string (addr, &buf[0], sizeof (buf)))
+ return FALSE;
+
+ /* searches are preferred over domains */
+ n = nm_ip6_config_get_num_searches (ip6);
+ for (i = 0; i < n; i++) {
+ g_string_append_printf (str, "server=/%s/%s\n",
+ nm_ip6_config_get_search (ip6, i),
+ buf);
+ added = TRUE;
+ }
+
+ if (n == 0) {
+ /* If not searches, use any domains */
+ n = nm_ip6_config_get_num_domains (ip6);
+ for (i = 0; i < n; i++) {
+ g_string_append_printf (str, "server=/%s/%s\n",
+ nm_ip6_config_get_domain (ip6, i),
+ buf);
+ added = TRUE;
+ }
+ }
+ }
+
+ /* If no searches or domains, just add the namservers */
+ if (!added) {
+ n = nm_ip6_config_get_num_nameservers (ip6);
+ for (i = 0; i < n; i++) {
+ addr = nm_ip6_config_get_nameserver (ip6, i);
+ if (ip6_addr_to_string (addr, &buf[0], sizeof (buf)))
+ g_string_append_printf (str, "server=%s\n", buf);
+ }
+ }
+
+ return TRUE;
+}
+
+static gboolean
+update (NMDnsPlugin *plugin,
+ const GSList *vpn_configs,
+ const GSList *dev_configs,
+ const GSList *other_configs,
+ const char *hostname)
+{
+ NMDnsDnsmasq *self = NM_DNS_DNSMASQ (plugin);
+ GString *conf;
+ GSList *iter;
+ const char *argv[10];
+ GError *error = NULL;
+ int ignored;
+ GPid pid = 0;
+
+ /* Kill the old dnsmasq; there doesn't appear to be a way to get dnsmasq
+ * to reread the config file using SIGHUP or similar. This is a small race
+ * here when restarting dnsmasq when DNS requests could go to the upstream
+ * servers instead of to dnsmasq.
+ */
+ nm_dns_plugin_child_kill (plugin);
+
+ /* Build up the new dnsmasq config file */
+ conf = g_string_sized_new (150);
+
+ /* Use split DNS for VPN configs */
+ for (iter = (GSList *) vpn_configs; iter; iter = g_slist_next (iter)) {
+ if (NM_IS_IP4_CONFIG (iter->data))
+ add_ip4_config (conf, NM_IP4_CONFIG (iter->data), TRUE);
+ else if (NM_IS_IP6_CONFIG (iter->data))
+ add_ip6_config (conf, NM_IP6_CONFIG (iter->data), TRUE);
+ }
+
+ /* Now add interface configs without split DNS */
+ for (iter = (GSList *) dev_configs; iter;iter = g_slist_next (iter)) {
+ if (NM_IS_IP4_CONFIG (iter->data))
+ add_ip4_config (conf, NM_IP4_CONFIG (iter->data), FALSE);
+ else if (NM_IS_IP6_CONFIG (iter->data))
+ add_ip6_config (conf, NM_IP6_CONFIG (iter->data), FALSE);
+ }
+
+ /* And any other random configs */
+ for (iter = (GSList *) other_configs; iter;iter = g_slist_next (iter)) {
+ if (NM_IS_IP4_CONFIG (iter->data))
+ add_ip4_config (conf, NM_IP4_CONFIG (iter->data), FALSE);
+ else if (NM_IS_IP6_CONFIG (iter->data))
+ add_ip6_config (conf, NM_IP6_CONFIG (iter->data), FALSE);
+ }
+
+ /* Write out the config file */
+ if (!g_file_set_contents (CONFFILE, conf->str, -1, &error)) {
+ nm_log_warn (LOGD_DNS, "Failed to write dnsmasq config file %s: (%d) %s",
+ CONFFILE,
+ error ? error->code : -1,
+ error && error->message ? error->message : "(unknown)");
+ g_clear_error (&error);
+ goto out;
+ }
+ ignored = chmod (CONFFILE, 0600);
+
+ nm_log_dbg (LOGD_DNS, "dnsmasq local caching DNS configuration:");
+ nm_log_dbg (LOGD_DNS, "%s", conf->str);
+
+ argv[0] = find_dnsmasq ();
+ argv[1] = "--no-resolv"; /* Use only commandline */
+ argv[2] = "--keep-in-foreground";
+ argv[3] = "--strict-order";
+ argv[4] = "--bind-interfaces";
+ argv[5] = "--pid-file=" PIDFILE;
+ argv[6] = "--listen-address=127.0.0.1"; /* Should work for both 4 and 6 */
+ argv[7] = "--conf-file=" CONFFILE;
+ argv[8] = NULL;
+
+ /* And finally spawn dnsmasq */
+ pid = nm_dns_plugin_child_spawn (NM_DNS_PLUGIN (self), argv, PIDFILE, "bin/dnsmasq");
+
+out:
+ g_string_free (conf, TRUE);
+ return pid ? TRUE : FALSE;
+}
+
+/****************************************************************/
+
+static const char *
+dm_exit_code_to_msg (int status)
+{
+ if (status == 1)
+ return "Configuration problem";
+ else if (status == 2)
+ return "Network access problem (address in use; permissions; etc)";
+ else if (status == 3)
+ return "Filesystem problem (missing file/directory; permissions; etc)";
+ else if (status == 4)
+ return "Memory allocation failure";
+ else if (status == 5)
+ return "Other problem";
+ else if (status >= 11)
+ return "Lease-script 'init' process failure";
+ return "Unknown error";
+}
+
+static void
+child_quit (NMDnsPlugin *plugin, gint status)
+{
+ NMDnsDnsmasq *self = NM_DNS_DNSMASQ (plugin);
+ gboolean failed = TRUE;
+ int err;
+
+ if (WIFEXITED (status)) {
+ err = WEXITSTATUS (status);
+ if (err) {
+ nm_log_warn (LOGD_DNS, "dnsmasq exited with error: %s (%d)",
+ dm_exit_code_to_msg (err),
+ err);
+ } else
+ failed = FALSE;
+ } else if (WIFSTOPPED (status)) {
+ nm_log_warn (LOGD_DNS, "dnsmasq stopped unexpectedly with signal %d", WSTOPSIG (status));
+ } else if (WIFSIGNALED (status)) {
+ nm_log_warn (LOGD_DNS, "dnsmasq died with signal %d", WTERMSIG (status));
+ } else {
+ nm_log_warn (LOGD_DNS, "dnsmasq died from an unknown cause");
+ }
+ unlink (CONFFILE);
+
+ if (failed)
+ g_signal_emit_by_name (self, NM_DNS_PLUGIN_FAILED);
+}
+
+/****************************************************************/
+
+static gboolean
+init (NMDnsPlugin *plugin)
+{
+ return TRUE;
+}
+
+static gboolean
+is_caching (NMDnsPlugin *plugin)
+{
+ return TRUE;
+}
+
+static const char *
+get_name (NMDnsPlugin *plugin)
+{
+ return "dnsmasq";
+}
+
+/****************************************************************/
+
+NMDnsDnsmasq *
+nm_dns_dnsmasq_new (void)
+{
+ return (NMDnsDnsmasq *) g_object_new (NM_TYPE_DNS_DNSMASQ, NULL);
+}
+
+static void
+nm_dns_dnsmasq_init (NMDnsDnsmasq *self)
+{
+}
+
+static void
+dispose (GObject *object)
+{
+ unlink (CONFFILE);
+
+ G_OBJECT_CLASS (nm_dns_dnsmasq_parent_class)->dispose (object);
+}
+
+static void
+nm_dns_dnsmasq_class_init (NMDnsDnsmasqClass *dns_class)
+{
+ NMDnsPluginClass *plugin_class = NM_DNS_PLUGIN_CLASS (dns_class);
+ GObjectClass *object_class = G_OBJECT_CLASS (dns_class);
+
+ g_type_class_add_private (dns_class, sizeof (NMDnsDnsmasqPrivate));
+
+ object_class->dispose = dispose;
+
+ plugin_class->init = init;
+ plugin_class->child_quit = child_quit;
+ plugin_class->is_caching = is_caching;
+ plugin_class->update = update;
+ plugin_class->get_name = get_name;
+}
+