Added IPv4 fallback, made IPv6 and IPv4 fallback enabled by default

other/bootstrap_daemon/tox-bootstrapd.c

@@ -53,7 +53,7 @@
 
 
 #define DAEMON_NAME "tox-bootstrapd"
-#define DAEMON_VERSION_NUMBER 2014101000UL // yyyymmmddvv format: yyyy year, mm month, dd day, vv version change count for that day
+#define DAEMON_VERSION_NUMBER 2014101200UL // yyyymmmddvv format: yyyy year, mm month, dd day, vv version change count for that day
 
 #define SLEEP_TIME_MILLISECONDS 30
 #define sleep usleep(1000*SLEEP_TIME_MILLISECONDS)
@@ -62,6 +62,7 @@
 #define DEFAULT_KEYS_FILE_PATH        "tox-bootstrapd.keys"
 #define DEFAULT_PORT                  33445
 #define DEFAULT_ENABLE_IPV6           1 // 1 - true, 0 - false
+#define DEFAULT_ENABLE_IPV4_FALLBACK  1 // 1 - true, 0 - false
 #define DEFAULT_ENABLE_LAN_DISCOVERY  1 // 1 - true, 0 - false
 #define DEFAULT_ENABLE_TCP_RELAY      1 // 1 - true, 0 - false
 #define DEFAULT_TCP_RELAY_PORTS       443, 3389, 33445 // comma-separated list of ports. make sure to adjust DEFAULT_TCP_RELAY_PORTS_COUNT accordingly
@@ -233,8 +234,8 @@ void parse_tcp_relay_ports_config(config_t *cfg, uint16_t **tcp_relay_ports, int
 //         0 on failure, doesn't modify any data pointed by arguments
 
 int get_general_config(char *cfg_file_path, char **pid_file_path, char **keys_file_path, int *port, int *enable_ipv6,
-                       int *enable_lan_discovery, int *enable_tcp_relay, uint16_t **tcp_relay_ports, int *tcp_relay_port_count,
+                       int *enable_ipv4_fallback, int *enable_lan_discovery, int *enable_tcp_relay, uint16_t **tcp_relay_ports,
-                       int *enable_motd, char **motd)
+                       int *tcp_relay_port_count, int *enable_motd, char **motd)
 {
     config_t cfg;
 
@@ -242,6 +243,7 @@ int get_general_config(char *cfg_file_path, char **pid_file_path, char **keys_fi
     const char *NAME_PID_FILE_PATH        = "pid_file_path";
     const char *NAME_KEYS_FILE_PATH       = "keys_file_path";
     const char *NAME_ENABLE_IPV6          = "enable_ipv6";
+    const char *NAME_ENABLE_IPV4_FALLBACK = "enable_ipv4_fallback";
     const char *NAME_ENABLE_LAN_DISCOVERY = "enable_lan_discovery";
     const char *NAME_ENABLE_TCP_RELAY     = "enable_tcp_relay";
     const char *NAME_ENABLE_MOTD          = "enable_motd";
@@ -294,6 +296,13 @@ int get_general_config(char *cfg_file_path, char **pid_file_path, char **keys_fi
         *enable_ipv6 = DEFAULT_ENABLE_IPV6;
     }
 
+    // Get IPv4 fallback option
+    if (config_lookup_bool(&cfg, NAME_ENABLE_IPV4_FALLBACK, enable_ipv4_fallback) == CONFIG_FALSE) {
+        syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_ENABLE_IPV4_FALLBACK);
+        syslog(LOG_WARNING, "Using default '%s': %s\n", NAME_ENABLE_IPV4_FALLBACK, DEFAULT_ENABLE_IPV4_FALLBACK ? "true" : "false");
+        *enable_ipv4_fallback = DEFAULT_ENABLE_IPV4_FALLBACK;
+    }
+
     // Get LAN discovery option
     if (config_lookup_bool(&cfg, NAME_ENABLE_LAN_DISCOVERY, enable_lan_discovery) == CONFIG_FALSE) {
         syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_ENABLE_LAN_DISCOVERY);
@@ -348,6 +357,7 @@ int get_general_config(char *cfg_file_path, char **pid_file_path, char **keys_fi
     syslog(LOG_DEBUG, "'%s': %s\n", NAME_KEYS_FILE_PATH,       *keys_file_path);
     syslog(LOG_DEBUG, "'%s': %d\n", NAME_PORT,                 *port);
     syslog(LOG_DEBUG, "'%s': %s\n", NAME_ENABLE_IPV6,          *enable_ipv6          ? "true" : "false");
+    syslog(LOG_DEBUG, "'%s': %s\n", NAME_ENABLE_IPV4_FALLBACK, *enable_ipv4_fallback ? "true" : "false");
     syslog(LOG_DEBUG, "'%s': %s\n", NAME_ENABLE_LAN_DISCOVERY, *enable_lan_discovery ? "true" : "false");
 
     syslog(LOG_DEBUG, "'%s': %s\n", NAME_ENABLE_TCP_RELAY,     *enable_tcp_relay     ? "true" : "false");
@@ -516,6 +526,7 @@ int main(int argc, char *argv[])
     char *pid_file_path, *keys_file_path;
     int port;
     int enable_ipv6;
+    int enable_ipv4_fallback;
     int enable_lan_discovery;
     int enable_tcp_relay;
     uint16_t *tcp_relay_ports;
@@ -523,8 +534,8 @@ int main(int argc, char *argv[])
     int enable_motd;
     char *motd;
 
-    if (get_general_config(cfg_file_path, &pid_file_path, &keys_file_path, &port, &enable_ipv6, &enable_lan_discovery,
+    if (get_general_config(cfg_file_path, &pid_file_path, &keys_file_path, &port, &enable_ipv6, &enable_ipv4_fallback,
-                           &enable_tcp_relay, &tcp_relay_ports, &tcp_relay_port_count, &enable_motd, &motd)) {
+                           &enable_lan_discovery, &enable_tcp_relay, &tcp_relay_ports, &tcp_relay_port_count, &enable_motd, &motd)) {
         syslog(LOG_DEBUG, "General config read successfully\n");
     } else {
         syslog(LOG_ERR, "Couldn't read config file: %s. Exiting.\n", cfg_file_path);
@@ -547,7 +558,26 @@ int main(int argc, char *argv[])
     IP ip;
     ip_init(&ip, enable_ipv6);
 
-    DHT *dht = new_DHT(new_networking(ip, port));
+    Networking_Core *net = new_networking(ip, port);
+
+    if (net == NULL) {
+        if (enable_ipv6 && enable_ipv4_fallback) {
+            syslog(LOG_DEBUG, "Couldn't initialize IPv6 networking. Falling back to using IPv4.\n");
+            enable_ipv6 = 0;
+            ip_init(&ip, enable_ipv6);
+            net = new_networking(ip, port);
+            if (net == NULL) {
+                syslog(LOG_DEBUG, "Couldn't fallback to IPv4. Exiting.\n");
+                return 1;
+            }
+        } else {
+            syslog(LOG_DEBUG, "Couldn't initialize networking. Exiting.\n");
+            return 1;
+        }
+    }
+
+
+    DHT *dht = new_DHT(net);
 
     if (dht == NULL) {
         syslog(LOG_ERR, "Couldn't initialize Tox DHT instance. Exiting.\n");

other/bootstrap_daemon/tox-bootstrapd.conf

@@ -1,46 +1,51 @@
 // Tox DHT bootstrap daemon configuration file.
 
-// Listening port.
+// Listening port (UDP).
 port = 33445
 
 // A key file is like a password, so keep it where no one can read it.
 // If there is no key file, a new one will be generated.
-// The daemon should have permission to read/write to it.
+// The daemon should have permission to read/write it.
 keys_file_path = "/var/lib/tox-bootstrapd/keys"
 
-// The PID file written to by daemon.
+// The PID file written to by the daemon.
-// Make sure that the user who runs the daemon has permissions to write to the
+// Make sure that the user that daemon runs as has permissions to write to the
 // PID file.
 pid_file_path = "/var/run/tox-bootstrapd/tox-bootstrapd.pid"
 
 // Enable IPv6.
-enable_ipv6 = false
+enable_ipv6 = true
+
+// Fallback to IPv4 in case IPv6 fails.
+enable_ipv4_fallback = true
 
 // Automatically bootstrap with nodes on local area network.
 enable_lan_discovery = true
 
 enable_tcp_relay = true
 
-// Tox uses 443, 3389 and 33445 ports by default, so it's highly recommended to keep
+// Tox uses 443, 3389 and 33445 ports by default, so it's highly encouraged to keep
 // them.
 tcp_relay_ports = [443, 3389, 33445]
 
-// It's planned to use message of the day as a convenient method of checking
+// Reply to MOTD (Message Of The Day) requests.
-// whether a node is up or not, though there are other methods of doing that.
 enable_motd = true
 
+// Just a message that is sent when someone requests MOTD.
+// Put anything you want, but note that it will be trimmed to fit into 255 bytes.
 motd = "tox-bootstrapd"
 
 // Any number of nodes the daemon will bootstrap itself off.
+//
 // Remember to replace the provided example with your own node list.
 // There is a maintained list of bootstrap nodes on Tox's wiki, if you need it
 // (http://wiki.tox.im/Nodes).
+//
 // You may leave the list empty or remove "bootstrap_nodes" completely,
 // in both cases this will be interpreted as if you don't want to bootstrap
 // from anyone.
-// address = any ipv4 or Any ipv4 or ipv6, depending on whether `enable_ipv6`
+//
-// is set or not, and also any US-ASCII domain name.
+// address = any ipv4 or ipv6 address and also any US-ASCII domain name.
-
 bootstrap_nodes = (
   {   
     // NikolaiToryzin - US