25 files changed, 1411 insertions, 298 deletions

diff --git a/auto_tests/messenger_test.c b/auto_tests/messenger_test.c
index 604e282c..6677c345 100644
--- a/auto_tests/messenger_test.c
+++ b/auto_tests/messenger_test.c
@@ -278,7 +278,8 @@ int main(int argc, char *argv[])
     good_id_b = hex_string_to_bin(good_id_b_str);
     bad_id    = hex_string_to_bin(bad_id_str);
 
-    m = initMessenger();
+    /* no IPv6 enabled yet */
+    m = initMessenger(0);
 
     /* setup a default friend and friendnum */
     if (m_addfriend_norequest(m, (uint8_t *)friend_id) < 0)
diff --git a/other/DHT_bootstrap.c b/other/DHT_bootstrap.c
index 654b759f..63cb1b75 100644
--- a/other/DHT_bootstrap.c
+++ b/other/DHT_bootstrap.c
@@ -84,10 +84,23 @@ void manage_keys(DHT *dht)
 
 int main(int argc, char *argv[])
 {
+    if (argc == 2 && !strncasecmp(argv[1], "-h", 3)) {
+        printf("Usage (connected)  : %s [--ipv4|--ipv6] IP PORT KEY\n", argv[0]);
+        printf("Usage (unconnected): %s [--ipv4|--ipv6]\n", argv[0]);
+        exit(0);
+    }
+
+    /* let user override default by cmdline */
+    uint8_t ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; /* x */
+    int argvoffset = cmdline_parsefor_ipv46(argc, argv, &ipv6enabled);
+    if (argvoffset < 0)
+        exit(1);
+
     /* Initialize networking -
-       Bind to ip 0.0.0.0:PORT */
+       Bind to ip 0.0.0.0 / [::] : PORT */
     IP ip;
-    ip.uint32 = 0;
+    ip_init(&ip, ipv6enabled);
+
     DHT *dht = new_DHT(new_net_crypto(new_networking(ip, PORT)));
     manage_keys(dht);
     printf("Public key: ");
@@ -111,14 +124,17 @@ int main(int argc, char *argv[])
 
     perror("Initialization.");
 
-    if (argc > 3) {
+    if (argc > argvoffset + 3) {
         printf("Trying to bootstrap into the network...\n");
-        IP_Port bootstrap_info;
-        bootstrap_info.ip.uint32 = inet_addr(argv[1]);
-        bootstrap_info.port = htons(atoi(argv[2]));
-        uint8_t *bootstrap_key = hex_string_to_bin(argv[3]);
-        DHT_bootstrap(dht, bootstrap_info, bootstrap_key);
+        uint16_t port = htons(atoi(argv[argvoffset + 2]));
+        uint8_t *bootstrap_key = hex_string_to_bin(argv[argvoffset + 3]);
+        int res = DHT_bootstrap_ex(dht, argv[argvoffset + 1], ipv6enabled, port, bootstrap_key);
         free(bootstrap_key);
+
+        if (!res) {
+            printf("Failed to convert \"%s\" into an IP address. Exiting...\n", argv[argvoffset + 1]);
+            exit(1);
+        }
     }
 
     int is_waiting_for_dht_connection = 1;
diff --git a/other/bootstrap_serverdaemon/DHT_bootstrap_daemon.c b/other/bootstrap_serverdaemon/DHT_bootstrap_daemon.c
index 0ef1f314..890085cc 100644
--- a/other/bootstrap_serverdaemon/DHT_bootstrap_daemon.c
+++ b/other/bootstrap_serverdaemon/DHT_bootstrap_daemon.c
@@ -305,7 +305,12 @@ struct server_conf_s configure_server(char *cfg_file)
                 printf("bootstrap_server %d: Invalid port.\n", i);
             }
 
+#ifdef TOX_ENABLE_IPV6
+            server_conf.info[i].conn.ip.family = AF_INET;
+            server_conf.info[i].conn.ip.ip4.uint32 = resolve_addr(strcpy(tmp_ip, bs_ip));
+#else
             server_conf.info[i].conn.ip.uint32 = resolve_addr(strcpy(tmp_ip, bs_ip));
+#endif
             server_conf.info[i].conn.port = htons(bs_port);
             b16_to_key(strcpy(tmp_pk, bs_pk), bs_pk_p);
         }
@@ -344,7 +349,7 @@ int main(int argc, char *argv[])
     /* Initialize networking
     bind to ip 0.0.0.0:PORT */
     IP ip;
-    ip.uint32 = 0;
+    ip_init(&ip, 0);
     DHT *dht = new_DHT(new_net_crypto(new_networking(ip, server_conf.port)));
     /* Read the config file */
     printf("PID file: %s\n", server_conf.pid_file);
diff --git a/testing/DHT_test.c b/testing/DHT_test.c
index fce9c257..ba8c2f23 100644
--- a/testing/DHT_test.c
+++ b/testing/DHT_test.c
@@ -66,13 +66,11 @@ void print_clientlist(DHT *dht)
         }
 
         p_ip = dht->close_clientlist[i].ip_port;
-        printf("\nIP: %u.%u.%u.%u Port: %u", p_ip.ip.uint8[0], p_ip.ip.uint8[1], p_ip.ip.uint8[2], p_ip.ip.uint8[3],
-               ntohs(p_ip.port));
+        printf("\nIP: %s Port: %u", ip_ntoa(&p_ip.ip), ntohs(p_ip.port));
         printf("\nTimestamp: %llu", (long long unsigned int) dht->close_clientlist[i].timestamp);
         printf("\nLast pinged: %llu\n", (long long unsigned int) dht->close_clientlist[i].last_pinged);
         p_ip = dht->close_clientlist[i].ret_ip_port;
-        printf("OUR IP: %u.%u.%u.%u Port: %u\n", p_ip.ip.uint8[0], p_ip.ip.uint8[1], p_ip.ip.uint8[2], p_ip.ip.uint8[3],
-               ntohs(p_ip.port));
+        printf("OUR IP: %s Port: %u\n", ip_ntoa(&p_ip.ip), ntohs(p_ip.port));
         printf("Timestamp: %llu\n", (long long unsigned int) dht->close_clientlist[i].ret_timestamp);
     }
 }
@@ -91,9 +89,8 @@ void print_friendlist(DHT *dht)
             printf("%c", dht->friends_list[k].client_id[j]);
         }
 
-        p_ip = DHT_getfriendip(dht, dht->friends_list[k].client_id);
-        printf("\nIP: %u.%u.%u.%u:%u", p_ip.ip.uint8[0], p_ip.ip.uint8[1], p_ip.ip.uint8[2], p_ip.ip.uint8[3],
-               ntohs(p_ip.port));
+        int friendok = DHT_getfriendip(dht, dht->friends_list[k].client_id, &p_ip);
+        printf("\nIP: %s:%u", ip_ntoa(&p_ip.ip), ntohs(p_ip.port));
 
         printf("\nCLIENTS IN LIST:\n\n");
 
@@ -108,13 +105,11 @@ void print_friendlist(DHT *dht)
             }
 
             p_ip = dht->friends_list[k].client_list[i].ip_port;
-            printf("\nIP: %u.%u.%u.%u:%u", p_ip.ip.uint8[0], p_ip.ip.uint8[1], p_ip.ip.uint8[2], p_ip.ip.uint8[3],
-                   ntohs(p_ip.port));
+            printf("\nIP: %s:%u", ip_ntoa(&p_ip.ip), ntohs(p_ip.port));
             printf("\nTimestamp: %llu", (long long unsigned int) dht->friends_list[k].client_list[i].timestamp);
             printf("\nLast pinged: %llu\n", (long long unsigned int) dht->friends_list[k].client_list[i].last_pinged);
             p_ip = dht->friends_list[k].client_list[i].ret_ip_port;
-            printf("ret IP: %u.%u.%u.%u:%u\n", p_ip.ip.uint8[0], p_ip.ip.uint8[1], p_ip.ip.uint8[2], p_ip.ip.uint8[3],
-                   ntohs(p_ip.port));
+            printf("ret IP: %s:%u\n", ip_ntoa(&p_ip.ip), ntohs(p_ip.port));
             printf("Timestamp: %llu\n", (long long unsigned int)dht->friends_list[k].client_list[i].ret_timestamp);
         }
     }
@@ -138,19 +133,25 @@ void printpacket(uint8_t *data, uint32_t length, IP_Port ip_port)
 
 int main(int argc, char *argv[])
 {
+    if (argc < 4) {
+        printf("Usage: %s [--ipv4|--ipv6] ip port public_key\n", argv[0]);
+        exit(0);
+    }
+
+    /* let user override default by cmdline */
+    uint8_t ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; /* x */
+    int argvoffset = cmdline_parsefor_ipv46(argc, argv, &ipv6enabled);
+    if (argvoffset < 0)
+        exit(1);
+
     //memcpy(self_client_id, "qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq", 32);
     /* initialize networking */
     /* bind to ip 0.0.0.0:PORT */
     IP ip;
-    ip.uint32 = 0;
+    ip_init(&ip, ipv6enabled);
 
     DHT *dht = new_DHT(new_net_crypto(new_networking(ip, PORT)));
 
-    if (argc < 4) {
-        printf("usage %s ip port public_key\n", argv[0]);
-        exit(0);
-    }
-
     new_keys(dht->c);
     printf("OUR ID: ");
     uint32_t i;
@@ -170,16 +171,16 @@ int main(int argc, char *argv[])
 
     DHT_addfriend(dht, hex_string_to_bin(temp_id));
 
-
     perror("Initialization");
-    IP_Port bootstrap_ip_port;
-    bootstrap_ip_port.port = htons(atoi(argv[2]));
-    /* bootstrap_ip_port.ip.c[0] = 127;
-     * bootstrap_ip_port.ip.c[1] = 0;
-     * bootstrap_ip_port.ip.c[2] = 0;
-     * bootstrap_ip_port.ip.c[3] = 1; */
-    bootstrap_ip_port.ip.uint32 = inet_addr(argv[1]);
-    DHT_bootstrap(dht, bootstrap_ip_port, hex_string_to_bin(argv[3]));
+
+    uint16_t port = htons(atoi(argv[argvoffset + 2]));
+    unsigned char *binary_string = hex_string_to_bin(argv[argvoffset + 3]);
+    int res = DHT_bootstrap_ex(dht, argv[argvoffset + 1], ipv6enabled, port, binary_string);
+    free(binary_string);
+    if (!res) {
+        printf("Failed to convert \"%s\" into an IP address. Exiting...\n", argv[argvoffset + 1]);
+        return 1;
+    }
 
     /*
         IP_Port ip_port;
diff --git a/testing/Lossless_UDP_testclient.c b/testing/Lossless_UDP_testclient.c
index d5fb1544..70349204 100644
--- a/testing/Lossless_UDP_testclient.c
+++ b/testing/Lossless_UDP_testclient.c
@@ -66,8 +66,7 @@ void printpacket(uint8_t *data, uint32_t length, IP_Port ip_port)
 
 void printip(IP_Port ip_port)
 {
-    printf("\nIP: %u.%u.%u.%u Port: %u", ip_port.ip.uint8[0], ip_port.ip.uint8[1], ip_port.ip.uint8[2], ip_port.ip.uint8[3],
-           ntohs(ip_port.port));
+    printf("\nIP: %s Port: %u", ip_ntoa(&ip_port.ip), ntohs(ip_port.port));
 }
 /*
 void printpackets(Data test)
@@ -152,30 +151,45 @@ void printconnection(int connection_id)
 
 int main(int argc, char *argv[])
 {
-    if (argc < 4) {
-        printf("usage: %s ip port filename\n", argv[0]);
+    /* let user override default by cmdline */
+    uint8_t ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; /* x */
+    int argvoffset = cmdline_parsefor_ipv46(argc, argv, &ipv6enabled);
+    if (argvoffset < 0)
+        exit(1);
+
+    if (argc < argvoffset + 4) {
+        printf("Usage: %s [--ipv4|--ipv6] ip port filename\n", argv[0]);
         exit(0);
     }
 
     uint8_t buffer[512];
     int read;
 
-    FILE *file = fopen(argv[3], "rb");
+    FILE *file = fopen(argv[argvoffset + 3], "rb");
 
-    if (file == NULL)
+    if (file == NULL) {
+        printf("Failed to open file \"%s\".\n", argv[argvoffset + 3]);
         return 1;
+    }
 
 
     /* initialize networking */
     /* bind to ip 0.0.0.0:PORT */
     IP ip;
-    ip.uint32 = 0;
+    ip_init(&ip, ipv6enabled);
+
     Lossless_UDP *ludp = new_lossless_udp(new_networking(ip, PORT));
     perror("Initialization");
+
     IP_Port serverip;
-    serverip.ip.uint32 = inet_addr(argv[1]);
-    serverip.port = htons(atoi(argv[2]));
+    ip_init(&serverip.ip, ipv6enabled);
+    if (!addr_resolve(argv[argvoffset + 1], &serverip.ip)) {
+        printf("Failed to convert \"%s\" into an IP address.\n", argv[argvoffset + 1]);
+        return 1;
+    }
+    serverip.port = htons(atoi(argv[argvoffset + 2]));
     printip(serverip);
+
     int connection = new_connection(ludp, serverip);
     uint64_t timer = current_time();
 
diff --git a/testing/Lossless_UDP_testserver.c b/testing/Lossless_UDP_testserver.c
index eb506b3d..343a662a 100644
--- a/testing/Lossless_UDP_testserver.c
+++ b/testing/Lossless_UDP_testserver.c
@@ -147,24 +147,33 @@ void printconnection(int connection_id)
 
 int main(int argc, char *argv[])
 {
-    if (argc < 2) {
-        printf("usage: %s filename\n", argv[0]);
+    /* let user override default by cmdline */
+    uint8_t ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; /* x */
+    int argvoffset = cmdline_parsefor_ipv46(argc, argv, &ipv6enabled);
+    if (argvoffset < 0)
+        exit(1);
+
+    if (argc < argvoffset + 2) {
+        printf("Usage: %s [--ipv4|--ipv6] filename\n", argv[0]);
         exit(0);
     }
 
     uint8_t buffer[512];
     int read;
 
-    FILE *file = fopen(argv[1], "wb");
+    FILE *file = fopen(argv[argvoffset + 1], "wb");
 
-    if (file == NULL)
+    if (file == NULL) {
+        printf("Failed to open file \"%s\".\n", argv[argvoffset + 1]);
         return 1;
+    }
 
 
     //initialize networking
     //bind to ip 0.0.0.0:PORT
     IP ip;
-    ip.uint32 = 0;
+    ip_init(&ip, ipv6enabled);
+
     Lossless_UDP *ludp = new_lossless_udp(new_networking(ip, PORT));
     perror("Initialization");
 
diff --git a/testing/Messenger_test.c b/testing/Messenger_test.c
index e85a85a2..14d9ca20 100644
--- a/testing/Messenger_test.c
+++ b/testing/Messenger_test.c
@@ -95,27 +95,40 @@ void print_message(Messenger *m, int friendnumber, uint8_t *string, uint16_t len
 
 int main(int argc, char *argv[])
 {
-    if (argc < 4 && argc != 2) {
-        printf("usage %s ip port public_key (of the DHT bootstrap node)\n or\n %s Save.bak\n", argv[0], argv[0]);
+    /* let user override default by cmdline */
+    uint8_t ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; /* x */
+    int argvoffset = cmdline_parsefor_ipv46(argc, argv, &ipv6enabled);
+    if (argvoffset < 0)
+        exit(1);
+
+    /* with optional --ipvx, now it can be 1-4 arguments... */
+    if ((argc != argvoffset + 2) && (argc != argvoffset + 4)) {
+        printf("Usage: %s [--ipv4|--ipv6] ip port public_key (of the DHT bootstrap node)\n", argv[0]);
+        printf("or\n");
+        printf("       %s [--ipv4|--ipv6] Save.bak (to read Save.bak as state file)\n", argv[0], argv[0]);
         exit(0);
     }
 
-    m = initMessenger();
+    m = initMessenger(ipv6enabled);
 
     if ( !m ) {
         fputs("Failed to allocate messenger datastructure\n", stderr);
         exit(0);
     }
 
-    if (argc > 3) {
-        IP_Port bootstrap_ip_port;
-        bootstrap_ip_port.port = htons(atoi(argv[2]));
-        bootstrap_ip_port.ip.uint32 = inet_addr(argv[1]);
-        DHT_bootstrap(m->dht, bootstrap_ip_port, hex_string_to_bin(argv[3]));
+    if (argc == argvoffset + 4) {
+        uint16_t port = htons(atoi(argv[argvoffset + 2]));
+        uint8_t *bootstrap_key = hex_string_to_bin(argv[argvoffset + 3]);
+        int res = DHT_bootstrap_ex(m->dht, argv[argvoffset + 1], ipv6enabled, port, bootstrap_key);
+        free(bootstrap_key);
+        if (!res) {
+            printf("Failed to convert \"%s\" into an IP address. Exiting...\n", argv[argvoffset + 1]);
+            exit(1);
+        }
     } else {
-        FILE *file = fopen(argv[1], "rb");
-
+        FILE *file = fopen(argv[argvoffset + 1], "rb");
         if ( file == NULL ) {
+            printf("Failed to open \"%s\" - does it exist?\n", argv[argvoffset + 1]);
             return 1;
         }
 
diff --git a/testing/nTox.c b/testing/nTox.c
index 438468bd..750970f9 100644
--- a/testing/nTox.c
+++ b/testing/nTox.c
@@ -537,6 +537,17 @@ void print_help(void)
 
 int main(int argc, char *argv[])
 {
+    if (argc < 4) {
+        printf("Usage: %s [--ipv4|--ipv6] IP PORT KEY [-f keyfile]\n", argv[0]);
+        exit(0);
+    }
+
+    /* let user override default by cmdline */
+    uint8_t ipv6enabled = TOX_ENABLE_IPV6_DEFAULT; /* x */
+    int argvoffset = cmdline_parsefor_ipv46(argc, argv, &ipv6enabled);
+    if (argvoffset < 0)
+        exit(1);
+
     int on = 0;
     int c = 0;
     int i = 0;
@@ -544,29 +555,18 @@ int main(int argc, char *argv[])
     char idstring[200] = {0};
     Tox *m;
 
-    if (argc < 4) {
-        printf("[!] Usage: %s [IP] [port] [public_key] <keyfile>\n", argv[0]);
+    if ((argc == 2) && !strcmp(argv[1], "-h")) {
+        print_help();
         exit(0);
     }
 
-    for (i = 0; i < argc; i++) {
-        if (argv[i] == NULL) {
-            break;
-        } else if (argv[i][0] == '-') {
-            if (argv[i][1] == 'h') {
-                print_help();
-                exit(0);
-            } else if (argv[i][1] == 'f') {
-                if (argv[i + 1] != NULL)
-                    filename = argv[i + 1];
-                else {
-                    fputs("[!] you passed '-f' without giving an argument!\n", stderr);
-                }
-            }
-        }
-    }
+    /* [-f keyfile] MUST be last two arguments, no point in walking over the list
+     * especially not a good idea to accept it anywhere in the middle */
+    if (argc > argvoffset + 3)
+        if (!strcmp(argv[argc - 2], "-f"))
+            filename = argv[argc - 1];
 
-    m = tox_new();
+    m = tox_new_ex(ipv6enabled);
 
     if ( !m ) {
         fputs("Failed to allocate Messenger datastructure", stderr);
@@ -590,20 +590,18 @@ int main(int argc, char *argv[])
     new_lines(idstring);
     strcpy(line, "");
 
-    tox_IP_Port bootstrap_ip_port;
-    bootstrap_ip_port.port = htons(atoi(argv[2]));
-    int resolved_address = resolve_addr(argv[1]);
+    uint16_t port = htons(atoi(argv[argvoffset + 2]));
+    unsigned char *binary_string = hex_string_to_bin(argv[argvoffset + 3]);
+    int res = tox_bootstrap_ex(m, argv[argvoffset + 1], ipv6enabled, port, binary_string);
+    free(binary_string);
 
-    if (resolved_address != 0)
-        bootstrap_ip_port.ip.i = resolved_address;
-    else
+    if (!res) {
+        printf("Failed to convert \"%s\" into an IP address. Exiting...\n", argv[argvoffset + 1]);
+        endwin();
         exit(1);
+    }
 
-    unsigned char *binary_string = hex_string_to_bin(argv[3]);
-    tox_bootstrap(m, bootstrap_ip_port, binary_string);
-    free(binary_string);
     nodelay(stdscr, TRUE);
-
     while (1) {
         if (on == 0 && tox_isconnected(m)) {
             new_lines("[i] connected to DHT\n[i] define username with /n");
diff --git a/toxcore/DHT.c b/toxcore/DHT.c
index e2d91256..1798ea1a 100644
--- a/toxcore/DHT.c
+++ b/toxcore/DHT.c
@@ -115,11 +115,6 @@ static int client_id_cmp(ClientPair p1, ClientPair p2)
     return c;
 }
 
-static int ipport_equal(IP_Port a, IP_Port b)
-{
-    return (a.ip.uint32 == b.ip.uint32) && (a.port == b.port);
-}
-
 static int id_equal(uint8_t *a, uint8_t *b)
 {
     return memcmp(a, b, CLIENT_ID_SIZE) == 0;
@@ -142,20 +137,23 @@ static int client_in_list(Client_data *list, uint32_t length, uint8_t *client_id
     uint32_t i;
     uint64_t temp_time = unix_time();
 
-    for (i = 0; i < length; ++i) {
-        /* If ip_port is assigned to a different client_id replace it */
-        if (ipport_equal(list[i].ip_port, ip_port)) {
-            memcpy(list[i].client_id, client_id, CLIENT_ID_SIZE);
+    /* if client_id is in list, find it and maybe overwrite ip_port */
+    for (i = 0; i < length; ++i)
+        if (id_equal(list[i].client_id, client_id)) {
+            /* Refresh the client timestamp. */
+            list[i].timestamp = temp_time;
+            list[i].ip_port = ip_port;
+            return 1;
         }
 
-        if (id_equal(list[i].client_id, client_id)) {
+    /* client_id not in list yet: find ip_port to overwrite */
+    for (i = 0; i < length; ++i)
+        if (ipport_equal(&list[i].ip_port, &ip_port)) {
             /* Refresh the client timestamp. */
             list[i].timestamp = temp_time;
-            list[i].ip_port.ip.uint32 = ip_port.ip.uint32;
-            list[i].ip_port.port = ip_port.port;
+            memcpy(list[i].client_id, client_id, CLIENT_ID_SIZE);
             return 1;
         }
-    }
 
     return 0;
 }
@@ -197,18 +195,37 @@ static int friend_number(DHT *dht, uint8_t *client_id)
  *
  * TODO: For the love of based Allah make this function cleaner and much more efficient.
  */
-static int get_close_nodes(DHT *dht, uint8_t *client_id, Node_format *nodes_list)
+static int get_close_nodes(DHT *dht, uint8_t *client_id, Node_format *nodes_list, sa_family_t sa_family)
 {
     uint32_t    i, j, k;
     uint64_t    temp_time = unix_time();
-    int         num_nodes = 0, closest, tout, inlist;
+    int         num_nodes = 0, closest, tout, inlist, ipv46x;
 
     for (i = 0; i < LCLIENT_LIST; ++i) {
         tout = is_timeout(temp_time, dht->close_clientlist[i].timestamp, BAD_NODE_TIMEOUT);
         inlist = client_in_nodelist(nodes_list, MAX_SENT_NODES, dht->close_clientlist[i].client_id);
 
+        /*
+         * NET_PACKET_SEND_NODES sends ONLY AF_INET
+         * NET_PACKET_SEND_NODES_EX sends ALL BUT AF_INET (i.e. AF_INET6),
+         *    it could send both, but then a) packet size is an issue and
+         *    b) duplicates the traffic (NET_PACKET_SEND_NODES has to be
+         *    sent anyways for backwards compatibility)
+         * we COULD send ALL as NET_PACKET_SEND_NODES_EX if we KNEW that the
+         * partner node understands - that's true if *they* are on IPv6
+         */
+#ifdef TOX_ENABLE_IPV6
+        ipv46x = 0;
+        if (sa_family == AF_INET)
+            ipv46x = dht->close_clientlist[i].ip_port.ip.family != AF_INET;
+        else
+            ipv46x = dht->close_clientlist[i].ip_port.ip.family == AF_INET;
+#else
+        ipv46x = sa_family != AF_INET;
+#endif
+
         /* If node isn't good or is already in list. */
-        if (tout || inlist)
+        if (tout || inlist || ipv46x)
             continue;
 
         if (num_nodes < MAX_SENT_NODES) {
@@ -247,8 +264,18 @@ static int get_close_nodes(DHT *dht, uint8_t *client_id, Node_format *nodes_list
                                             MAX_SENT_NODES,
                                             dht->friends_list[i].client_list[j].client_id);
 
+#ifdef TOX_ENABLE_IPV6
+            ipv46x = 0;
+            if (sa_family == AF_INET)
+                ipv46x = dht->friends_list[i].client_list[j].ip_port.ip.family != AF_INET;
+            else
+                ipv46x = dht->friends_list[i].client_list[j].ip_port.ip.family == AF_INET;
+#else
+            ipv46x = sa_family != AF_INET;
+#endif
+
             /* If node isn't good or is already in list. */
-            if (tout || inlist)
+            if (tout || inlist || ipv46x)
                 continue;
 
             if (num_nodes < MAX_SENT_NODES) {
@@ -301,7 +328,7 @@ static int replace_bad(    Client_data    *list,
             memcpy(list[i].client_id, client_id, CLIENT_ID_SIZE);
             list[i].ip_port = ip_port;
             list[i].timestamp = temp_time;
-            list[i].ret_ip_port.ip.uint32 = 0;
+            ip_reset(&list[i].ret_ip_port.ip);
             list[i].ret_ip_port.port = 0;
             list[i].ret_timestamp = 0;
             return 0;
@@ -349,7 +376,7 @@ static int replace_good(   Client_data    *list,
             memcpy(list[i].client_id, client_id, CLIENT_ID_SIZE);
             list[i].ip_port = ip_port;
             list[i].timestamp = temp_time;
-            list[i].ret_ip_port.ip.uint32 = 0;
+            ip_reset(&list[i].ret_ip_port.ip);
             list[i].ret_ip_port.port = 0;
             list[i].ret_timestamp = 0;
             return 0;
@@ -447,13 +474,13 @@ static int is_gettingnodes(DHT *dht, IP_Port ip_port, uint64_t ping_id)
         if (!is_timeout(temp_time, dht->send_nodes[i].timestamp, PING_TIMEOUT)) {
             pinging = 0;
 
-            if (ip_port.ip.uint32 != 0 && ipport_equal(dht->send_nodes[i].ip_port, ip_port))
+            if (ping_id != 0 && dht->send_nodes[i].ping_id == ping_id)
                 ++pinging;
 
-            if (ping_id != 0 && dht->send_nodes[i].ping_id == ping_id)
+            if (ip_isset(&ip_port.ip) && ipport_equal(&dht->send_nodes[i].ip_port, &ip_port))
                 ++pinging;
 
-            if (pinging == (ping_id != 0) + (ip_port.ip.uint32 != 0))
+            if (pinging == (ping_id != 0) + (ip_isset(&ip_port.ip) != 0))
                 return 1;
         }
     }
@@ -518,44 +545,65 @@ static int getnodes(DHT *dht, IP_Port ip_port, uint8_t *public_key, uint8_t *cli
     memcpy(data + 1 + CLIENT_ID_SIZE, nonce, crypto_box_NONCEBYTES);
     memcpy(data + 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES, encrypt, len);
 
-    return sendpacket(dht->c->lossless_udp->net->sock, ip_port, data, sizeof(data));
+    return sendpacket(dht->c->lossless_udp->net, ip_port, data, sizeof(data));
 }
 
 /* Send a send nodes response. */
+/* because of BINARY compatibility, the Node_format MUST BE Node4_format,
+ * IPv6 nodes are sent in a different message */
 static int sendnodes(DHT *dht, IP_Port ip_port, uint8_t *public_key, uint8_t *client_id, uint64_t ping_id)
 {
     /* Check if packet is going to be sent to ourself. */
     if (id_equal(public_key, dht->c->self_public_key))
         return -1;
 
+    size_t Node4_format_size = sizeof(Node4_format);
     uint8_t data[1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES + sizeof(ping_id)
-                 + sizeof(Node_format) * MAX_SENT_NODES + ENCRYPTION_PADDING];
+                 + Node4_format_size * MAX_SENT_NODES + ENCRYPTION_PADDING];
 
     Node_format nodes_list[MAX_SENT_NODES];
-    int num_nodes = get_close_nodes(dht, client_id, nodes_list);
+    int num_nodes = get_close_nodes(dht, client_id, nodes_list, AF_INET);
 
     if (num_nodes == 0)
         return 0;
 
-    uint8_t plain[sizeof(ping_id) + sizeof(Node_format) * MAX_SENT_NODES];
-    uint8_t encrypt[sizeof(ping_id) + sizeof(Node_format) * MAX_SENT_NODES + ENCRYPTION_PADDING];
+    uint8_t plain[sizeof(ping_id) + Node4_format_size * MAX_SENT_NODES];
+    uint8_t encrypt[sizeof(ping_id) + Node4_format_size * MAX_SENT_NODES + ENCRYPTION_PADDING];
     uint8_t nonce[crypto_box_NONCEBYTES];
     random_nonce(nonce);
 
     memcpy(plain, &ping_id, sizeof(ping_id));
-    memcpy(plain + sizeof(ping_id), nodes_list, num_nodes * sizeof(Node_format));
+#ifdef TOX_ENABLE_IPV6
+    Node4_format *nodes4_list = (Node4_format *)(plain + sizeof(ping_id));
+    int i, num_nodes_ok = 0;
+    for(i = 0; i < num_nodes; i++)
+        if (nodes_list[i].ip_port.ip.family == AF_INET) {
+            memcpy(nodes4_list[num_nodes_ok].client_id, nodes_list[i].client_id, CLIENT_ID_SIZE);
+            nodes4_list[num_nodes_ok].ip_port.ip.uint32 = nodes_list[i].ip_port.ip.ip4.uint32;
+            nodes4_list[num_nodes_ok].ip_port.port = nodes_list[i].ip_port.port;
+
+            num_nodes_ok++;
+        }
+
+    if (num_nodes_ok < num_nodes) {
+        /* shouldn't happen */
+        num_nodes = num_nodes_ok;
+    }
+#else
+    memcpy(plain + sizeof(ping_id), nodes_list, num_nodes * Node4_format_size);
+#endif
 
     int len = encrypt_data( public_key,
                             dht->c->self_secret_key,
                             nonce,
                             plain,
-                            sizeof(ping_id) + num_nodes * sizeof(Node_format),
+                            sizeof(ping_id) + num_nodes * Node4_format_size,
                             encrypt );
 
     if (len == -1)
         return -1;
 
-    if ((unsigned int)len != sizeof(ping_id) + num_nodes * sizeof(Node_format) + ENCRYPTION_PADDING)
+    if ((unsigned int)len != sizeof(ping_id) + num_nodes * Node4_format_size + ENCRYPTION_PADDING)
         return -1;
 
     data[0] = NET_PACKET_SEND_NODES;
@@ -563,9 +611,57 @@ static int sendnodes(DHT *dht, IP_Port ip_port, uint8_t *public_key, uint8_t *cl
     memcpy(data + 1 + CLIENT_ID_SIZE, nonce, crypto_box_NONCEBYTES);
     memcpy(data + 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES, encrypt, len);
 
-    return sendpacket(dht->c->lossless_udp->net->sock, ip_port, data, 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES + len);
+    return sendpacket(dht->c->lossless_udp->net, ip_port, data, 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES + len);
 }
 
+#ifdef TOX_ENABLE_IPV6
+/* Send a send nodes response: message for IPv6 nodes */
+static int sendnodes_ex(DHT *dht, IP_Port ip_port, uint8_t *public_key, uint8_t *client_id, uint64_t ping_id)
+{
+    /* Check if packet is going to be sent to ourself. */
+    if (id_equal(public_key, dht->c->self_public_key))
+        return -1;
+
+    size_t Node_format_size = sizeof(Node_format);
+    uint8_t data[1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES + sizeof(ping_id)
+                 + Node_format_size * MAX_SENT_NODES + ENCRYPTION_PADDING];
+
+    Node_format nodes_list[MAX_SENT_NODES];
+    int num_nodes = get_close_nodes(dht, client_id, nodes_list, AF_INET6);
+
+    if (num_nodes == 0)
+        return 0;
+
+    uint8_t plain[sizeof(ping_id) + Node_format_size * MAX_SENT_NODES];
+    uint8_t encrypt[sizeof(ping_id) + Node_format_size * MAX_SENT_NODES + ENCRYPTION_PADDING];
+    uint8_t nonce[crypto_box_NONCEBYTES];
+    random_nonce(nonce);
+
+    memcpy(plain, &ping_id, sizeof(ping_id));
+    memcpy(plain + sizeof(ping_id), nodes_list, num_nodes * Node_format_size);
+
+    int len = encrypt_data( public_key,
+                            dht->c->self_secret_key,
+                            nonce,
+                            plain,
+                            sizeof(ping_id) + num_nodes * Node_format_size,
+                            encrypt );
+
+    if (len == -1)
+        return -1;
+
+    if ((unsigned int)len != sizeof(ping_id) + num_nodes * Node_format_size + ENCRYPTION_PADDING)
+        return -1;
+
+    data[0] = NET_PACKET_SEND_NODES_EX;
+    memcpy(data + 1, dht->c->self_public_key, CLIENT_ID_SIZE);
+    memcpy(data + 1 + CLIENT_ID_SIZE, nonce, crypto_box_NONCEBYTES);
+    memcpy(data + 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES, encrypt, len);
+
+    return sendpacket(dht->c->lossless_udp->net, ip_port, data, 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES + len);
+}
+#endif
+
 static int handle_getnodes(void *object, IP_Port source, uint8_t *packet, uint32_t length)
 {
     DHT *dht = object;
@@ -593,6 +689,9 @@ static int handle_getnodes(void *object, IP_Port source, uint8_t *packet, uint32
 
     memcpy(&ping_id, plain, sizeof(ping_id));
     sendnodes(dht, source, packet + 1, plain + sizeof(ping_id), ping_id);
+#ifdef TOX_ENABLE_IPV6
+    sendnodes_ex(dht, source, packet + 1, plain + sizeof(ping_id), ping_id);
+#endif
 
     //send_ping_request(dht, source, packet + 1); /* TODO: make this smarter? */
 
@@ -606,22 +705,23 @@ static int handle_sendnodes(void *object, IP_Port source, uint8_t *packet, uint3
     uint32_t cid_size = 1 + CLIENT_ID_SIZE;
     cid_size += crypto_box_NONCEBYTES + sizeof(ping_id) + ENCRYPTION_PADDING;
 
-    if (length > (cid_size + sizeof(Node_format) * MAX_SENT_NODES) ||
-            ((length - cid_size) % sizeof(Node_format)) != 0 ||
-            (length < cid_size + sizeof(Node_format)))
+    size_t Node4_format_size = sizeof(Node4_format);
+    if (length > (cid_size + Node4_format_size * MAX_SENT_NODES) ||
+            ((length - cid_size) % Node4_format_size) != 0 ||
+            (length < cid_size + Node4_format_size))
         return 1;
 
-    uint32_t num_nodes = (length - cid_size) / sizeof(Node_format);
-    uint8_t plain[sizeof(ping_id) + sizeof(Node_format) * MAX_SENT_NODES];
+    uint32_t num_nodes = (length - cid_size) / Node4_format_size;
+    uint8_t plain[sizeof(ping_id) + Node4_format_size * MAX_SENT_NODES];
 
     int len = decrypt_data(
                   packet + 1,
                   dht->c->self_secret_key,
                   packet + 1 + CLIENT_ID_SIZE,
                   packet + 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES,
-                  sizeof(ping_id) + num_nodes * sizeof(Node_format) + ENCRYPTION_PADDING, plain );
+                  sizeof(ping_id) + num_nodes * Node4_format_size + ENCRYPTION_PADDING, plain );
 
-    if ((unsigned int)len != sizeof(ping_id) + num_nodes * sizeof(Node_format))
+    if ((unsigned int)len != sizeof(ping_id) + num_nodes * Node4_format_size)
         return 1;
 
     memcpy(&ping_id, plain, sizeof(ping_id));
@@ -629,12 +729,78 @@ static int handle_sendnodes(void *object, IP_Port source, uint8_t *packet, uint3
     if (!is_gettingnodes(dht, source, ping_id))
         return 1;
 
+    uint32_t i;
     Node_format nodes_list[MAX_SENT_NODES];
+
+#ifdef TOX_ENABLE_IPV6
+    Node4_format *nodes4_list = (Node4_format *)(plain + sizeof(ping_id));
+
+    int num_nodes_ok = 0;
+    for(i = 0; i < num_nodes; i++)
+        if ((nodes4_list[i].ip_port.ip.uint32 != 0) && (nodes4_list[i].ip_port.ip.uint32 != ~0)) {
+            memcpy(nodes_list[num_nodes_ok].client_id, nodes4_list[i].client_id, CLIENT_ID_SIZE);
+            nodes_list[num_nodes_ok].ip_port.ip.family = AF_INET;
+            nodes_list[num_nodes_ok].ip_port.ip.ip4.uint32 = nodes4_list[i].ip_port.ip.uint32;
+            nodes_list[num_nodes_ok].ip_port.port = nodes4_list[i].ip_port.port;
+
+            num_nodes_ok++;
+        }
+
+    if (num_nodes_ok < num_nodes) {
+        /* shouldn't happen */
+        num_nodes = num_nodes_ok;
+    }
+#else
     memcpy(nodes_list, plain + sizeof(ping_id), num_nodes * sizeof(Node_format));
+#endif
 
     addto_lists(dht, source, packet + 1);
 
+    for (i = 0; i < num_nodes; ++i)  {
+        send_ping_request(dht->ping, dht->c, nodes_list[i].ip_port, nodes_list[i].client_id);
+        returnedip_ports(dht, nodes_list[i].ip_port, nodes_list[i].client_id, packet + 1);
+    }
+
+    return 0;
+}
+
+#ifdef TOX_ENABLE_IPV6
+static int handle_sendnodes_ex(void *object, IP_Port source, uint8_t *packet, uint32_t length)
+{
+    DHT *dht = object;
+    uint64_t ping_id;
+    uint32_t cid_size = 1 + CLIENT_ID_SIZE;
+    cid_size += crypto_box_NONCEBYTES + sizeof(ping_id) + ENCRYPTION_PADDING;
+
+    size_t Node_format_size = sizeof(Node4_format);
+    if (length > (cid_size + Node_format_size * MAX_SENT_NODES) ||
+            ((length - cid_size) % Node_format_size) != 0 ||
+            (length < cid_size + Node_format_size))
+        return 1;
+
+    uint32_t num_nodes = (length - cid_size) / Node_format_size;
+    uint8_t plain[sizeof(ping_id) + Node_format_size * MAX_SENT_NODES];
+
+    int len = decrypt_data(
+                  packet + 1,
+                  dht->c->self_secret_key,
+                  packet + 1 + CLIENT_ID_SIZE,
+                  packet + 1 + CLIENT_ID_SIZE + crypto_box_NONCEBYTES,
+                  sizeof(ping_id) + num_nodes * Node_format_size + ENCRYPTION_PADDING, plain );
+
+    if ((unsigned int)len != sizeof(ping_id) + num_nodes * Node_format_size)
+        return 1;
+
+    memcpy(&ping_id, plain, sizeof(ping_id));
+
+    if (!is_gettingnodes(dht, source, ping_id))
+        return 1;
+
     uint32_t i;
+    Node_format nodes_list[MAX_SENT_NODES];
+    memcpy(nodes_list, plain + sizeof(ping_id), num_nodes * sizeof(Node_format));
+
+    addto_lists(dht, source, packet + 1);
 
     for (i = 0; i < num_nodes; ++i)  {
         send_ping_request(dht->ping, dht->c, nodes_list[i].ip_port, nodes_list[i].client_id);
@@ -643,6 +809,7 @@ static int handle_sendnodes(void *object, IP_Port source, uint8_t *packet, uint3
 
     return 0;
 }
+#endif
 
 /*----------------------------------------------------------------------------------*/
 /*------------------------END of packet handling functions--------------------------*/
@@ -703,27 +870,30 @@ int DHT_delfriend(DHT *dht, uint8_t *client_id)
 }
 
 /* TODO: Optimize this. */
-IP_Port DHT_getfriendip(DHT *dht, uint8_t *client_id)
+int DHT_getfriendip(DHT *dht, uint8_t *client_id, IP_Port *ip_port)
 {
     uint32_t i, j;
     uint64_t temp_time = unix_time();
-    IP_Port empty = {{{{0}}, 0, 0}};
+
+    ip_reset(&ip_port->ip);
+    ip_port->port = 0;
 
     for (i = 0; i < dht->num_friends; ++i) {
         /* Equal */
         if (id_equal(dht->friends_list[i].client_id, client_id)) {
             for (j = 0; j < MAX_FRIEND_CLIENTS; ++j) {
                 if (id_equal(dht->friends_list[i].client_list[j].client_id, client_id)
-                        && !is_timeout(temp_time, dht->friends_list[i].client_list[j].timestamp, BAD_NODE_TIMEOUT))
-                    return dht->friends_list[i].client_list[j].ip_port;
+                        && !is_timeout(temp_time, dht->friends_list[i].client_list[j].timestamp, BAD_NODE_TIMEOUT)) {
+                    *ip_port = dht->friends_list[i].client_list[j].ip_port;
+                    return 1;
+                }
             }
 
-            return empty;
+            return 0;
         }
     }
 
-    empty.ip.uint32 = 1;
-    return empty;
+    return -1;
 }
 
 /* Ping each client in the "friends" list every PING_INTERVAL seconds. Send a get nodes request
@@ -808,6 +978,18 @@ void DHT_bootstrap(DHT *dht, IP_Port ip_port, uint8_t *public_key)
     getnodes(dht, ip_port, public_key, dht->c->self_public_key);
     send_ping_request(dht->ping, dht->c, ip_port, public_key);
 }
+int DHT_bootstrap_ex(DHT *dht, const char *address, uint8_t ipv6enabled, uint16_t port, uint8_t *public_key)
+{
+    IP_Port ip_port;
+    ip_init(&ip_port.ip, ipv6enabled);
+    if (addr_resolve_or_parse_ip(address, &ip_port.ip)) {
+        ip_port.port = port;
+        DHT_bootstrap(dht, ip_port, public_key);
+        return 1;
+    }
+    else
+        return 0;
+}
 
 /* Send the given packet to node with client_id
  *
@@ -819,7 +1001,7 @@ int route_packet(DHT *dht, uint8_t *client_id, uint8_t *packet, uint32_t length)
 
     for (i = 0; i < LCLIENT_LIST; ++i) {
         if (id_equal(client_id, dht->close_clientlist[i].client_id))
-            return sendpacket(dht->c->lossless_udp->net->sock, dht->close_clientlist[i].ip_port, packet, length);
+            return sendpacket(dht->c->lossless_udp->net, dht->close_clientlist[i].ip_port, packet, length);
     }
 
     return -1;
@@ -848,7 +1030,7 @@ static int friend_iplist(DHT *dht, IP_Port *ip_portlist, uint16_t friend_num)
         client = &friend->client_list[i];
 
         /* If ip is not zero and node is good. */
-        if (client->ret_ip_port.ip.uint32 != 0 && !is_timeout(temp_time, client->ret_timestamp, BAD_NODE_TIMEOUT)) {
+        if (ip_isset(&client->ret_ip_port.ip) && !is_timeout(temp_time, client->ret_timestamp, BAD_NODE_TIMEOUT)) {
 
             if (id_equal(client->client_id, friend->client_id))
                 return 0;
@@ -890,8 +1072,8 @@ int route_tofriend(DHT *dht, uint8_t *friend_id, uint8_t *packet, uint32_t lengt
         client = &friend->client_list[i];
 
         /* If ip is not zero and node is good. */
-        if (client->ret_ip_port.ip.uint32 != 0 && !is_timeout(temp_time, client->ret_timestamp, BAD_NODE_TIMEOUT)) {
-            int retval = sendpacket(dht->c->lossless_udp->net->sock, client->ip_port, packet, length);
+        if (ip_isset(&client->ret_ip_port.ip) && !is_timeout(temp_time, client->ret_timestamp, BAD_NODE_TIMEOUT)) {
+            int retval = sendpacket(dht->c->lossless_udp->net, client->ip_port, packet, length);
 
             if ((unsigned int)retval == length)
                 ++sent;
@@ -924,7 +1106,7 @@ static int routeone_tofriend(DHT *dht, uint8_t *friend_id, uint8_t *packet, uint
         client = &friend->client_list[i];
 
         /* If ip is not zero and node is good. */
-        if (client->ret_ip_port.ip.uint32 != 0 && !is_timeout(temp_time, client->ret_timestamp, BAD_NODE_TIMEOUT)) {
+        if (ip_isset(&client->ret_ip_port.ip) && !is_timeout(temp_time, client->ret_timestamp, BAD_NODE_TIMEOUT)) {
             ip_list[n] = client->ip_port;
             ++n;
         }
@@ -933,7 +1115,7 @@ static int routeone_tofriend(DHT *dht, uint8_t *friend_id, uint8_t *packet, uint
     if (n < 1)
         return 0;
 
-    int retval = sendpacket(dht->c->lossless_udp->net->sock, ip_list[rand() % n], packet, length);
+    int retval = sendpacket(dht->c->lossless_udp->net, ip_list[rand() % n], packet, length);
 
     if ((unsigned int)retval == length)
         return 1;
@@ -1032,7 +1214,8 @@ static int handle_NATping(void *object, IP_Port source, uint8_t *source_pubkey,
  */
 static IP NAT_commonip(IP_Port *ip_portlist, uint16_t len, uint16_t min_num)
 {
-    IP zero = {{0}};
+    IP zero;
+    ip_reset(&zero);
 
     if (len > MAX_FRIEND_CLIENTS)
         return zero;
@@ -1042,7 +1225,7 @@ static IP NAT_commonip(IP_Port *ip_portlist, uint16_t len, uint16_t min_num)
 
     for (i = 0; i < len; ++i) {
         for (j = 0; j < len; ++j) {
-            if (ip_portlist[i].ip.uint32 == ip_portlist[j].ip.uint32)
+            if (ip_equal(&ip_portlist[i].ip, &ip_portlist[j].ip))
                 ++numbers[i];
         }
 
@@ -1065,7 +1248,7 @@ static uint16_t NAT_getports(uint16_t *portlist, IP_Port *ip_portlist, uint16_t
     uint16_t num = 0;
 
     for (i = 0; i < len; ++i) {
-        if (ip_portlist[i].ip.uint32 == ip.uint32) {
+        if (ip_equal(&ip_portlist[i].ip, &ip)) {
             portlist[num] = ntohs(ip_portlist[i].port);
             ++num;
         }
@@ -1085,7 +1268,9 @@ static void punch_holes(DHT *dht, IP ip, uint16_t *port_list, uint16_t numports,
     for (i = dht->friends_list[friend_num].punching_index; i != top; i++) {
         /* TODO: Improve port guessing algorithm. */
         uint16_t port = port_list[(i / 2) % numports] + (i / (2 * numports)) * ((i % 2) ? -1 : 1);
-        IP_Port pinging = {{ip, htons(port), 0}};
+        IP_Port pinging;
+        ip_copy(&pinging.ip, &ip);
+        pinging.port = htons(port);
         send_ping_request(dht->ping, dht->c, pinging, dht->friends_list[friend_num].client_id);
     }
 
@@ -1115,8 +1300,7 @@ static void do_NAT(DHT *dht)
                 dht->friends_list[i].recvNATping_timestamp + PUNCH_INTERVAL * 2 >= temp_time) {
 
             IP ip = NAT_commonip(ip_list, num, MAX_FRIEND_CLIENTS / 2);
-
-            if (ip.uint32 == 0)
+            if (!ip_isset(&ip))
                 continue;
 
             uint16_t port_list[MAX_FRIEND_CLIENTS];
@@ -1145,16 +1329,15 @@ static void do_NAT(DHT *dht)
  */
 int add_toping(DHT *dht, uint8_t *client_id, IP_Port ip_port)
 {
-    if (ip_port.ip.uint32 == 0)
+    if (!ip_isset(&ip_port.ip))
         return -1;
 
     uint32_t i;
 
     for (i = 0; i < MAX_TOPING; ++i) {
-        if (dht->toping[i].ip_port.ip.uint32 == 0) {
+        if (!ip_isset(&dht->toping[i].ip_port.ip)) {
             memcpy(dht->toping[i].client_id, client_id, CLIENT_ID_SIZE);
-            dht->toping[i].ip_port.ip.uint32 = ip_port.ip.uint32;
-            dht->toping[i].ip_port.port = ip_port.port;
+            ipport_copy(&dht->toping[i].ip_port, &ip_port);
             return 0;
         }
     }
@@ -1162,8 +1345,7 @@ int add_toping(DHT *dht, uint8_t *client_id, IP_Port ip_port)
     for (i = 0; i < MAX_TOPING; ++i) {
         if (id_closest(dht->c->self_public_key, dht->toping[i].client_id, client_id) == 2) {
             memcpy(dht->toping[i].client_id, client_id, CLIENT_ID_SIZE);
-            dht->toping[i].ip_port.ip.uint32 = ip_port.ip.uint32;
-            dht->toping[i].ip_port.port = ip_port.port;
+            ipport_copy(&dht->toping[i].ip_port, &ip_port);
             return 0;
         }
     }
@@ -1185,11 +1367,11 @@ static void do_toping(DHT *dht)
     uint32_t i;
 
     for (i = 0; i < MAX_TOPING; ++i) {
-        if (dht->toping[i].ip_port.ip.uint32 == 0)
+        if (!ip_isset(&dht->toping[i].ip_port.ip))
             return;
 
         send_ping_request(dht->ping, dht->c, dht->toping[i].ip_port, dht->toping[i].client_id);
-        dht->toping[i].ip_port.ip.uint32 = 0;
+        ip_reset(&dht->toping[i].ip_port.ip);
     }
 }
 
@@ -1216,6 +1398,9 @@ DHT *new_DHT(Net_Crypto *c)
     networking_registerhandler(c->lossless_udp->net, NET_PACKET_PING_RESPONSE, &handle_ping_response, temp);
     networking_registerhandler(c->lossless_udp->net, NET_PACKET_GET_NODES, &handle_getnodes, temp);
     networking_registerhandler(c->lossless_udp->net, NET_PACKET_SEND_NODES, &handle_sendnodes, temp);
+#ifdef TOX_ENABLE_IPV6
+    networking_registerhandler(c->lossless_udp->net, NET_PACKET_SEND_NODES_EX, &handle_sendnodes_ex, temp);
+#endif
     init_cryptopackets(temp);
     cryptopacket_registerhandler(c, CRYPTO_PACKET_NAT_PING, &handle_NATping, temp);
     return temp;
diff --git a/toxcore/DHT.h b/toxcore/DHT.h
index e5122b5e..90b76a2f 100644
--- a/toxcore/DHT.h
+++ b/toxcore/DHT.h
@@ -75,10 +75,22 @@ typedef struct {
     uint64_t    NATping_timestamp;
 } DHT_Friend;
 
+/* this must be kept even if IP_Port is expanded: wire compatibility */
+typedef struct {
+    uint8_t     client_id[CLIENT_ID_SIZE];
+    IP4_Port    ip_port;
+} Node4_format;
+
 typedef struct {
     uint8_t     client_id[CLIENT_ID_SIZE];
     IP_Port     ip_port;
-} Node_format;
+} Node46_format;
+
+#ifdef TOX_ENABLE_IPV6
+typedef Node46_format Node_format;
+#else
+typedef Node4_format Node_format;
+#endif
 
 typedef struct {
     IP_Port     ip_port;
@@ -88,15 +100,15 @@ typedef struct {
 
 /*----------------------------------------------------------------------------------*/
 typedef struct {
-    Net_Crypto *c;
+    Net_Crypto  *c;
     Client_data  close_clientlist[LCLIENT_LIST];
-    DHT_Friend      *friends_list;
+    DHT_Friend  *friends_list;
     uint16_t     num_friends;
     Pinged       send_nodes[LSEND_NODES_ARRAY];
     Node_format  toping[MAX_TOPING];
     uint64_t     last_toping;
-    uint64_t close_lastgetnodes;
-    void *ping;
+    uint64_t     close_lastgetnodes;
+    void        *ping;
 } DHT;
 /*----------------------------------------------------------------------------------*/
 
@@ -124,19 +136,31 @@ int DHT_delfriend(DHT *dht, uint8_t *client_id);
  *  ip must be 4 bytes long.
  *  port must be 2 bytes long.
  *
+ * !!! Signature changed!!!
+ *
+ * OLD: IP_Port DHT_getfriendip(DHT *dht, uint8_t *client_id);
+ *
  *  return ip if success.
  *  return ip of 0 if failure (This means the friend is either offline or we have not found him yet).
  *  return ip of 1 if friend is not in list.
+ *
+ * NEW: int DHT_getfriendip(DHT *dht, uint8_t *client_id, IP_Port *ip_port);
+ *
+ *  return -1, -- if client_id does NOT refer to a friend
+ *  return  0, -- if client_id refers to a friend and we failed to find the friend (yet)
+ *  return  1, ip if client_id refers to a friend and we found him
  */
-IP_Port DHT_getfriendip(DHT *dht, uint8_t *client_id);
+int DHT_getfriendip(DHT *dht, uint8_t *client_id, IP_Port *ip_port);
 
 /* Run this function at least a couple times per second (It's the main loop). */
 void do_DHT(DHT *dht);
 
 /* Use this function to bootstrap the client.
  *  Sends a get nodes request to the given node with ip port and public_key.
+ * DHT_bootstrap_ex() returns 1 if the address could be converted, 0 otherwise
  */
 void DHT_bootstrap(DHT *dht, IP_Port ip_port, uint8_t *public_key);
+int DHT_bootstrap_ex(DHT *dht, const char *address, uint8_t ipv6enabled, uint16_t port, uint8_t *public_key);
 
 /* Add nodes to the toping list.
  * All nodes in this list are pinged every TIME_TOPING seconds
diff --git a/toxcore/LAN_discovery.c b/toxcore/LAN_discovery.c
index 1980cd93..4cbe3177 100644
--- a/toxcore/LAN_discovery.c
+++ b/toxcore/LAN_discovery.c
@@ -71,7 +71,7 @@ static uint32_t send_broadcasts(Networking_Core *net, uint16_t port, uint8_t * d
             sock_holder = (struct sockaddr_in *)&i_faces[i].ifr_broadaddr;
             if (sock_holder != NULL) {
                 IP_Port ip_port = {{{{sock_holder->sin_addr.s_addr}}, port, 0}};
-                sendpacket(net->sock, ip_port, data, 1 + crypto_box_PUBLICKEYBYTES);
+                sendpacket(net, ip_port, data, 1 + crypto_box_PUBLICKEYBYTES);
             }
     }
 
@@ -81,10 +81,32 @@ static uint32_t send_broadcasts(Networking_Core *net, uint16_t port, uint8_t * d
 #endif
 
 /* Return the broadcast ip. */
-static IP broadcast_ip(void)
+static IP broadcast_ip(sa_family_t sa_family)
 {
     IP ip;
-    ip.uint32 = ~0;
+    ip_reset(&ip);
+
+#ifdef TOX_ENABLE_IPV6
+    if (sa_family == AF_INET)
+    {
+        ip.family = AF_INET;
+        ip.ip4.uint32 = INADDR_BROADCAST;
+    }
+
+    if (sa_family == AF_INET6)
+    {
+        ip.family = AF_INET6;
+        /* FF02::1 is - according to RFC 4291 - multicast all-nodes link-local */
+        /* FE80::*: MUST be exact, for that we would need to look over all
+         * interfaces and check in which status they are */
+        ip.ip6.s6_addr[ 0] = 0xFF;
+        ip.ip6.s6_addr[ 1] = 0x02;
+        ip.ip6.s6_addr[15] = 0x01;
+    }
+#else
+    ip.uint32 = INADDR_BROADCAST;
+#endif
+
     return ip;
 }
 
@@ -93,21 +115,42 @@ static IP broadcast_ip(void)
  */
 static int LAN_ip(IP ip)
 {
-    if (ip.uint8[0] == 127) /* Loopback. */
-        return 0;
-
-    if (ip.uint8[0] == 10) /* 10.0.0.0 to 10.255.255.255 range. */
-        return 0;
-
-    if (ip.uint8[0] == 172 && ip.uint8[1] >= 16 && ip.uint8[1] <= 31) /* 172.16.0.0 to 172.31.255.255 range. */
-        return 0;
-
-    if (ip.uint8[0] == 192 && ip.uint8[1] == 168) /* 192.168.0.0 to 192.168.255.255 range. */
-        return 0;
-
-    if (ip.uint8[0] == 169 && ip.uint8[1] == 254 && ip.uint8[2] != 0
-            && ip.uint8[2] != 255)/* 169.254.1.0 to 169.254.254.255 range. */
-        return 0;
+#ifdef TOX_ENABLE_IPV6
+    if (ip.family == AF_INET) {
+        IP4 ip4 = ip.ip4;
+#else
+        IP4 ip4 = ip;
+#endif
+        /* Loopback. */
+        if (ip4.uint8[0] == 127)
+            return 0;
+
+        /* 10.0.0.0 to 10.255.255.255 range. */
+        if (ip4.uint8[0] == 10)
+            return 0;
+
+        /* 172.16.0.0 to 172.31.255.255 range. */
+        if (ip4.uint8[0] == 172 && ip4.uint8[1] >= 16 && ip4.uint8[1] <= 31)
+            return 0;
+
+        /* 192.168.0.0 to 192.168.255.255 range. */
+        if (ip4.uint8[0] == 192 && ip4.uint8[1] == 168)
+            return 0;
+
+        /* 169.254.1.0 to 169.254.254.255 range. */
+        if (ip4.uint8[0] == 169 && ip4.uint8[1] == 254 && ip4.uint8[2] != 0
+                && ip4.uint8[2] != 255)
+            return 0;
+#ifdef TOX_ENABLE_IPV6
+    }
+    else if (ip.family == AF_INET6) {
+        /* autogenerated for each interface: FE80::* (up to FEBF::*)
+        /* FF02::1 is - according to RFC 4291 - multicast all-nodes link-local */
+        if (((ip.ip6.s6_addr[0] == 0xFF) && (ip.ip6.s6_addr[1] < 3) && (ip.ip6.s6_addr[15] == 1)) ||
+             ((ip.ip6.s6_addr[0] == 0xFE) && ((ip.ip6.s6_addr[1] & 0xC0) == 0x80)))
+            return 0;
+    }
+#endif
 
     return -1;
 }
@@ -135,8 +178,10 @@ int send_LANdiscovery(uint16_t port, Net_Crypto *c)
 #ifdef __linux
     send_broadcasts(c->lossless_udp->net, port, data, 1 + crypto_box_PUBLICKEYBYTES);
 #endif
-    IP_Port ip_port = {{broadcast_ip(), port, 0}};
-    return sendpacket(c->lossless_udp->net->sock, ip_port, data, 1 + crypto_box_PUBLICKEYBYTES);
+    IP_Port ip_port;
+    ip_port.ip = broadcast_ip(c->lossless_udp->net->family);
+    ip_port.port = port;
+    return sendpacket(c->lossless_udp->net, ip_port, data, 1 + crypto_box_PUBLICKEYBYTES);
 }
 
 
diff --git a/toxcore/Lossless_UDP.c b/toxcore/Lossless_UDP.c
index fbb473e7..ca874562 100644
--- a/toxcore/Lossless_UDP.c
+++ b/toxcore/Lossless_UDP.c
@@ -44,9 +44,7 @@
 int getconnection_id(Lossless_UDP *ludp, IP_Port ip_port)
 {
     tox_array_for_each(&ludp->connections, Connection, tmp) {
-        if (tmp->ip_port.ip.uint32 == ip_port.ip.uint32 &&
-                tmp->ip_port.port == ip_port.port &&
-                tmp->status > 0) {
+        if (tmp-> status > 0 && ipport_equal(&tmp->ip_port, &ip_port)) {
             return tmp_i;
         }
     }
@@ -61,17 +59,49 @@ int getconnection_id(Lossless_UDP *ludp, IP_Port ip_port)
  *
  * TODO: make this better
  */
-static uint32_t handshake_id(Lossless_UDP *ludp, IP_Port source)
+
+static uint8_t randtable_initget(Lossless_UDP *ludp, uint32_t index,  uint8_t value)
 {
-    uint32_t id = 0, i;
+    if (ludp->randtable[index][value] == 0)
+        ludp->randtable[index][value] = random_int();
 
-    for (i = 0; i < 6; ++i) {
-        if (ludp->randtable[i][source.uint8[i]] == 0)
-            ludp->randtable[i][source.uint8[i]] = random_int();
+    return ludp->randtable[index][value];
+}
 
-        id ^= ludp->randtable[i][source.uint8[i]];
+static uint32_t handshake_id(Lossless_UDP *ludp, IP_Port source)
+{
+    uint32_t id = 0, i = 0;
+
+    uint8_t *uint8;
+    uint8 = (uint8_t *)&source.port;
+    id ^= randtable_initget(ludp, i, *uint8);
+    i++, uint8++;
+    id ^= randtable_initget(ludp, i, *uint8);
+    i++;
+
+#ifdef TOX_ENABLE_IPV6
+    if (source.ip.family == AF_INET)
+    {
+        IP4 ip4 = source.ip.ip4;
+#else
+        IP4 ip4 = source.ip;
+#endif
+        int k;
+        for (k = 0; k < 4; k++) {
+            id ^= randtable_initget(ludp, i++, ip4.uint8[k]);
+        }
+#ifdef TOX_ENABLE_IPV6
     }
 
+    if (source.ip.family == AF_INET6)
+    {
+        int k;
+        for (k = 0; k < 16; k++) {
+            id ^= randtable_initget(ludp, i++, source.ip.ip6.s6_addr[k]);
+        }
+    }
+#endif
+
     /* id can't be zero. */
     if (id == 0)
         id = 1;
@@ -290,7 +320,9 @@ IP_Port connection_ip(Lossless_UDP *ludp, int connection_id)
     if ((unsigned int)connection_id < ludp->connections.len)
         return tox_array_get(&ludp->connections, connection_id, Connection).ip_port;
 
-    IP_Port zero = {{{{0}}, 0, 0}};
+    IP_Port zero;
+    ip_reset(&zero.ip);
+    zero.port = 0;
     return zero;
 }
 
@@ -429,7 +461,7 @@ static int send_handshake(Lossless_UDP *ludp, IP_Port ip_port, uint32_t handshak
     temp = htonl(handshake_id2);
     memcpy(packet + 5, &temp, 4);
 
-    return sendpacket(ludp->net->sock, ip_port, packet, sizeof(packet));
+    return sendpacket(ludp->net, ip_port, packet, sizeof(packet));
 }
 
 static int send_SYNC(Lossless_UDP *ludp, int connection_id)
@@ -456,7 +488,7 @@ static int send_SYNC(Lossless_UDP *ludp, int connection_id)
     index += 4;
     memcpy(packet + index, requested, 4 * number);
 
-    return sendpacket(ludp->net->sock, ip_port, packet, (number * 4 + 4 + 4 + 2));
+    return sendpacket(ludp->net, ip_port, packet, (number * 4 + 4 + 4 + 2));
 
 }
 
@@ -471,7 +503,7 @@ static int send_data_packet(Lossless_UDP *ludp, int connection_id, uint32_t pack
     temp = htonl(packet_num);
     memcpy(packet + 1, &temp, 4);
     memcpy(packet + 5, connection->sendbuffer[index].data, connection->sendbuffer[index].size);
-    return sendpacket(ludp->net->sock, connection->ip_port, packet, 1 + 4 + connection->sendbuffer[index].size);
+    return sendpacket(ludp->net, connection->ip_port, packet, 1 + 4 + connection->sendbuffer[index].size);
 }
 
 /* Sends 1 data packet. */
diff --git a/toxcore/Lossless_UDP.h b/toxcore/Lossless_UDP.h
index 20471b0a..f0ce0e87 100644
--- a/toxcore/Lossless_UDP.h
+++ b/toxcore/Lossless_UDP.h
@@ -123,7 +123,13 @@ typedef struct {
     tox_array connections;
 
     /* Table of random numbers used in handshake_id. */
+#ifdef TOX_ENABLE_IPV6
+    /* IPv6 (16) + port (2)*/
+    uint32_t randtable[18][256];
+#else
+    /* IPv4 (4) + port (2) */
     uint32_t randtable[6][256];
+#endif
 
 } Lossless_UDP;
 
diff --git a/toxcore/Messenger.c b/toxcore/Messenger.c
index b712d142..b955ad5a 100644
--- a/toxcore/Messenger.c
+++ b/toxcore/Messenger.c
@@ -651,7 +651,7 @@ static void LANdiscovery(Messenger *m)
 }
 
 /* Run this at startup. */
-Messenger *initMessenger(void)
+Messenger *initMessenger(uint8_t ipv6enabled)
 {
     Messenger *m = calloc(1, sizeof(Messenger));
 
@@ -659,7 +659,7 @@ Messenger *initMessenger(void)
         return NULL;
 
     IP ip;
-    ip.uint32 = 0;
+    ip_init(&ip, ipv6enabled);
     m->net = new_networking(ip, PORT);
 
     if (m->net == NULL) {
@@ -743,11 +743,12 @@ void doFriends(Messenger *m)
                 }
             }
 
-            IP_Port friendip = DHT_getfriendip(m->dht, m->friendlist[i].client_id);
+            IP_Port friendip;
+            int friendok = DHT_getfriendip(m->dht, m->friendlist[i].client_id, &friendip);
 
             switch (is_cryptoconnected(m->net_crypto, m->friendlist[i].crypt_connection_id)) {
                 case 0:
-                    if (friendip.ip.uint32 > 1)
+                    if (friendok == 1)
                         m->friendlist[i].crypt_connection_id = crypto_connect(m->net_crypto, m->friendlist[i].client_id, friendip);
 
                     break;
@@ -964,19 +965,23 @@ void Messenger_save(Messenger *m, uint8_t *data)
 {
     save_keys(m->net_crypto, data);
     data += crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES;
+
     uint32_t nospam = get_nospam(&(m->fr));
     memcpy(data, &nospam, sizeof(nospam));
     data += sizeof(nospam);
+
     uint32_t size = DHT_size(m->dht);
     memcpy(data, &size, sizeof(size));
     data += sizeof(size);
     DHT_save(m->dht, data);
     data += size;
+
     size = sizeof(Friend) * m->numfriends;
     memcpy(data, &size, sizeof(size));
     data += sizeof(size);
     memcpy(data, m->friendlist, sizeof(Friend) * m->numfriends);
     data += size;
+
     uint16_t small_size = m->name_length;
     memcpy(data, &small_size, sizeof(small_size));
     data += sizeof(small_size);
@@ -989,59 +994,64 @@ int Messenger_load(Messenger *m, uint8_t *data, uint32_t length)
     if (length == ~((uint32_t)0))
         return -1;
 
-    if (length < crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES + sizeof(uint32_t) * 3)
+    /* BLOCK1: PUBKEY, SECKEY, NOSPAM, SIZE */
+    if (length < crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES + sizeof(uint32_t) * 2)
         return -1;
 
-    length -= crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES + sizeof(uint32_t) * 3;
     load_keys(m->net_crypto, data);
     data += crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES;
+    length -= crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES;
+
     uint32_t nospam;
     memcpy(&nospam, data, sizeof(nospam));
     set_nospam(&(m->fr), nospam);
     data += sizeof(nospam);
+    length -= sizeof(nospam);
+
     uint32_t size;
     memcpy(&size, data, sizeof(size));
     data += sizeof(size);
+    length -= sizeof(size);
 
     if (length < size)
         return -1;
 
-    length -= size;
-
     if (DHT_load(m->dht, data, size) == -1)
-        return -1;
+        fprintf(stderr, "Data file: Something wicked happened to the stored connections.\n");
+
+    /* go on, friends still might be intact */
 
     data += size;
+    length -= size;
+
     memcpy(&size, data, sizeof(size));
     data += sizeof(size);
-
-    if (length < size || size % sizeof(Friend) != 0)
+    if (length < size)
         return -1;
 
-    Friend *temp = malloc(size);
-    memcpy(temp, data, size);
-
-    uint16_t num = size / sizeof(Friend);
-
-    uint32_t i;
-
-    for (i = 0; i < num; ++i) {
-        if (temp[i].status >= 3) {
-            int fnum = m_addfriend_norequest(m, temp[i].client_id);
-            setfriendname(m, fnum, temp[i].name, temp[i].name_length);
-            /* set_friend_statusmessage(fnum, temp[i].statusmessage, temp[i].statusmessage_length); */
-        } else if (temp[i].status != 0) {
-            /* TODO: This is not a good way to do this. */
-            uint8_t address[FRIEND_ADDRESS_SIZE];
-            memcpy(address, temp[i].client_id, crypto_box_PUBLICKEYBYTES);
-            memcpy(address + crypto_box_PUBLICKEYBYTES, &(temp[i].friendrequest_nospam), sizeof(uint32_t));
-            uint16_t checksum = address_checksum(address, FRIEND_ADDRESS_SIZE - sizeof(checksum));
-            memcpy(address + crypto_box_PUBLICKEYBYTES + sizeof(uint32_t), &checksum, sizeof(checksum));
-            m_addfriend(m, address, temp[i].info, temp[i].info_size);
+    if (!(size % sizeof(Friend))) {
+        uint16_t num = size / sizeof(Friend);
+        Friend temp[num];
+        memcpy(temp, data, size);
+
+        uint32_t i;
+        for (i = 0; i < num; ++i) {
+            if (temp[i].status >= 3) {
+                int fnum = m_addfriend_norequest(m, temp[i].client_id);
+                setfriendname(m, fnum, temp[i].name, temp[i].name_length);
+                /* set_friend_statusmessage(fnum, temp[i].statusmessage, temp[i].statusmessage_length); */
+            } else if (temp[i].status != 0) {
+                /* TODO: This is not a good way to do this. */
+                uint8_t address[FRIEND_ADDRESS_SIZE];
+                memcpy(address, temp[i].client_id, crypto_box_PUBLICKEYBYTES);
+                memcpy(address + crypto_box_PUBLICKEYBYTES, &(temp[i].friendrequest_nospam), sizeof(uint32_t));
+                uint16_t checksum = address_checksum(address, FRIEND_ADDRESS_SIZE - sizeof(checksum));
+                memcpy(address + crypto_box_PUBLICKEYBYTES + sizeof(uint32_t), &checksum, sizeof(checksum));
+                m_addfriend(m, address, temp[i].info, temp[i].info_size);
+            }
         }
     }
 
-    free(temp);
     data += size;
     length -= size;
 
diff --git a/toxcore/Messenger.h b/toxcore/Messenger.h
index 40617d08..dfb3f7c6 100644
--- a/toxcore/Messenger.h
+++ b/toxcore/Messenger.h
@@ -371,7 +371,7 @@ void m_callback_connectionstatus(Messenger *m, void (*function)(Messenger *m, in
  *  return allocated instance of Messenger on success.
  *  return 0 if there are problems.
  */
-Messenger *initMessenger(void);
+Messenger *initMessenger(uint8_t ipv6enabled);
 
 /* Run this before closing shop
  * Free all datastructures.
diff --git a/toxcore/friend_requests.c b/toxcore/friend_requests.c
index b01015c4..c821d998 100644
--- a/toxcore/friend_requests.c
+++ b/toxcore/friend_requests.c
@@ -50,18 +50,22 @@ int send_friendrequest(DHT *dht, uint8_t *public_key, uint32_t nospam_num, uint8
     if (len == -1)
         return -1;
 
-    IP_Port ip_port = DHT_getfriendip(dht, public_key);
+    IP_Port ip_port;
+    int friendok = DHT_getfriendip(dht, public_key, &ip_port);
 
-    if (ip_port.ip.uint32 == 1)
+    // not a friend
+    if (friendok == -1)
         return -1;
 
-    if (ip_port.ip.uint32 != 0) {
-        if (sendpacket(dht->c->lossless_udp->net->sock, ip_port, packet, len) != -1)
+    // is a friend and we know how to reach him
+    if (friendok == 1) {
+        if (sendpacket(dht->c->lossless_udp->net, ip_port, packet, len) != -1)
             return 0;
 
         return -1;
     }
 
+    // is a friend, we DON'T know how to reach him
     int num = route_tofriend(dht, public_key, packet, len);
 
     if (num == 0)
diff --git a/toxcore/group_chats.c b/toxcore/group_chats.c
index 4581eb38..4ee487d9 100644
--- a/toxcore/group_chats.c
+++ b/toxcore/group_chats.c
@@ -189,7 +189,7 @@ static int send_groupchatpacket(Group_Chat *chat, IP_Port ip_port, uint8_t *publ
     if (len == -1)
         return -1;
 
-    if (sendpacket(chat->net->sock, ip_port, packet, len) == len)
+    if (sendpacket(chat->net, ip_port, packet, len) == len)
         return 0;
 
     return -1;
@@ -208,7 +208,7 @@ static uint8_t sendto_allpeers(Group_Chat *chat, uint8_t *data, uint16_t length,
     uint64_t temp_time = unix_time();
 
     for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) {
-        if (chat->close[i].ip_port.ip.uint32 != 0 && chat->close[i].last_recv + BAD_NODE_TIMEOUT > temp_time) {
+        if (ip_isset(&chat->close[i].ip_port.ip) && chat->close[i].last_recv + BAD_NODE_TIMEOUT > temp_time) {
             if (send_groupchatpacket(chat, chat->close[i].ip_port, chat->close[i].client_id, data, length, request_id) == 0)
                 ++sent;
         }
diff --git a/toxcore/net_crypto.c b/toxcore/net_crypto.c
index a182bb53..b6f08fe4 100644
--- a/toxcore/net_crypto.c
+++ b/toxcore/net_crypto.c
@@ -439,7 +439,7 @@ int crypto_connect(Net_Crypto *c, uint8_t *public_key, IP_Port ip_port)
     if (id != -1) {
         IP_Port c_ip = connection_ip(c->lossless_udp, c->crypto_connections[id].number);
 
-        if (c_ip.ip.uint32 == ip_port.ip.uint32 && c_ip.port == ip_port.port)
+        if (ipport_equal(&c_ip, &ip_port))
             return -1;
     }
 
diff --git a/toxcore/network.c b/toxcore/network.c
index ed3dff8a..0b5eba61 100644
--- a/toxcore/network.c
+++ b/toxcore/network.c
@@ -26,6 +26,7 @@
 #endif
 
 #include "network.h"
+#include "util.h"
 
 /*  return current UNIX time in microseconds (us). */
 uint64_t current_time(void)
@@ -61,17 +62,76 @@ uint32_t random_int(void)
 #endif
 }
 
+#ifdef LOGGING
+static void loglogdata(char *message, uint8_t *buffer, size_t buflen, IP_Port *ip_port, ssize_t res);
+#endif
+
 /* Basic network functions:
  * Function to send packet(data) of length length to ip_port.
  */
-#ifdef WIN32
-int sendpacket(unsigned int sock, IP_Port ip_port, uint8_t *data, uint32_t length)
+int sendpacket(Networking_Core *net, IP_Port ip_port, uint8_t *data, uint32_t length)
+{
+#ifdef TOX_ENABLE_IPV6
+    /* socket AF_INET, but target IP NOT: can't send */
+   if ((net->family == AF_INET) && (ip_port.ip.family != AF_INET))
+        return 0;
+#endif
+ 
+    struct sockaddr_storage addr;
+    size_t addrsize = 0;
+
+#ifdef TOX_ENABLE_IPV6
+    if (ip_port.ip.family == AF_INET) {
+        if (net->family == AF_INET6) {
+            /* must convert to IPV4-in-IPV6 address */
+            addrsize = sizeof(struct sockaddr_in6);
+            struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&addr;
+            addr6->sin6_family = AF_INET6;
+            addr6->sin6_port = ip_port.port;
+
+            /* there should be a macro for this in a standards compliant
+             * environment, not found */
+            addr6->sin6_addr.s6_addr32[0] = 0;
+            addr6->sin6_addr.s6_addr32[1] = 0;
+            addr6->sin6_addr.s6_addr32[2] = htonl(0xFFFF);
+            addr6->sin6_addr.s6_addr32[3] = ip_port.ip.ip4.uint32;
+
+            addr6->sin6_flowinfo = 0;
+            addr6->sin6_scope_id = 0;
+        }
+        else {
+            IP4 ip4 = ip_port.ip.ip4;
 #else
-int sendpacket(int sock, IP_Port ip_port, uint8_t *data, uint32_t length)
+            IP4 ip4 = ip_port.ip;
 #endif
-{
-    ADDR addr = {AF_INET, ip_port.port, ip_port.ip, {0}};
-    return sendto(sock, (char *) data, length, 0, (struct sockaddr *)&addr, sizeof(addr));
+            addrsize = sizeof(struct sockaddr_in);
+            struct sockaddr_in *addr4 = (struct sockaddr_in *)&addr;
+            addr4->sin_family = AF_INET;
+            addr4->sin_addr = ip4.in_addr;
+            addr4->sin_port = ip_port.port;
+#ifdef TOX_ENABLE_IPV6
+        }
+    }
+    else if (ip_port.ip.family == AF_INET6) {
+        addrsize = sizeof(struct sockaddr_in6);
+        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&addr;
+        addr6->sin6_family = AF_INET6;
+        addr6->sin6_port = ip_port.port;
+        addr6->sin6_addr = ip_port.ip.ip6;
+
+        addr6->sin6_flowinfo = 0;
+        addr6->sin6_scope_id = 0;
+    } else {
+        /* unknown address type*/
+        return 0;
+    }
+#endif
+
+    int res = sendto(net->sock, (char *) data, length, 0, (struct sockaddr *)&addr, addrsize);
+#ifdef LOGGING
+    loglogdata("O=>", data, length, &ip_port, res);
+#endif
+    return res;
 }
 
 /* Function to receive data
@@ -80,13 +140,9 @@ int sendpacket(int sock, IP_Port ip_port, uint8_t *data, uint32_t length)
  *  Packet length is put into length.
  *  Dump all empty packets.
  */
-#ifdef WIN32
-static int receivepacket(unsigned int sock, IP_Port *ip_port, uint8_t *data, uint32_t *length)
-#else
-static int receivepacket(int sock, IP_Port *ip_port, uint8_t *data, uint32_t *length)
-#endif
+static int receivepacket(sock_t sock, IP_Port *ip_port, uint8_t *data, uint32_t *length)
 {
-    ADDR addr;
+    struct sockaddr_storage addr;
 #ifdef WIN32
     int addrlen = sizeof(addr);
 #else
@@ -94,11 +150,43 @@ static int receivepacket(int sock, IP_Port *ip_port, uint8_t *data, uint32_t *le
 #endif
     (*(int32_t *)length) = recvfrom(sock, (char *) data, MAX_UDP_PACKET_SIZE, 0, (struct sockaddr *)&addr, &addrlen);
 
-    if (*(int32_t *)length <= 0)
+    if (*(int32_t *)length <= 0) {
+#ifdef LOGGING
+        if ((length < 0) && (errno != EWOULDBLOCK))
+            sprintf(logbuffer, "Unexpected error reading from socket: %u, %s\n", errno, strerror(errno));
+#endif
         return -1; /* Nothing received or empty packet. */
+    }
+
+#ifdef TOX_ENABLE_IPV6
+    if (addr.ss_family == AF_INET) {
+        struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr;
+        ip_port->ip.family = addr_in->sin_family;
+        ip_port->ip.ip4.in_addr = addr_in->sin_addr;
+        ip_port->port = addr_in->sin_port;
+    }
+    else if (addr.ss_family == AF_INET6) {
+        struct sockaddr_in6 *addr_in6 = (struct sockaddr_in6 *)&addr;
+        ip_port->ip.family = addr_in6->sin6_family;
+        ip_port->ip.ip6 = addr_in6->sin6_addr;
+        ip_port->port = addr_in6->sin6_port;
+    }
+    else
+        return -1;
+#else
+    if (addr.ss_family == AF_INET) {
+        struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr;
+        ip_port->ip.in_addr = addr_in->sin_addr;
+        ip_port->port = addr_in->sin_port;
+    }
+    else
+        return -1;
+#endif
+
+#ifdef LOGGING
+    loglogdata("=>O", data, *length, ip_port, 0);
+#endif
 
-    ip_port->ip = addr.ip;
-    ip_port->port = addr.port;
     return 0;
 }
 
@@ -162,16 +250,31 @@ static void at_shutdown(void)
  */
 Networking_Core *new_networking(IP ip, uint16_t port)
 {
+#ifdef TOX_ENABLE_IPV6
+    /* maybe check for invalid IPs like 224+.x.y.z? if there is any IP set ever */
+    if (ip.family != AF_INET && ip.family != AF_INET6)
+        return NULL;
+#endif
+
     if (at_startup() != 0)
         return NULL;
 
-    /* Initialize our socket. */
     Networking_Core *temp = calloc(1, sizeof(Networking_Core));
-
     if (temp == NULL)
         return NULL;
 
-    temp->sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+    sa_family_t family = 0;
+#ifdef TOX_ENABLE_IPV6
+    family = ip.family;
+#else
+    family = AF_INET;
+#endif
+    temp->family = family;
+    temp->port = 0;
+
+    /* Initialize our socket. */
+    /* add log message what we're creating */
+    temp->sock = socket(temp->family, SOCK_DGRAM, IPPROTO_UDP);
 
     /* Check for socket error. */
 #ifdef WIN32
@@ -204,7 +307,7 @@ Networking_Core *new_networking(IP ip, uint16_t port)
         return -1;
     */
 
-    /* Enable broadcast on socket. */
+    /* Enable broadcast on socket? */
     int broadcast = 1;
     setsockopt(temp->sock, SOL_SOCKET, SO_BROADCAST, (char *)&broadcast, sizeof(broadcast));
 
@@ -218,10 +321,106 @@ Networking_Core *new_networking(IP ip, uint16_t port)
     fcntl(temp->sock, F_SETFL, O_NONBLOCK, 1);
 #endif
 
-    /* Bind our socket to port PORT and address 0.0.0.0 */
-    ADDR addr = {AF_INET, htons(port), ip, {0}};
-    bind(temp->sock, (struct sockaddr *)&addr, sizeof(addr));
-    return temp;
+#ifdef LOGGING
+    loginit(ntohs(port));
+#endif
+
+    /* Bind our socket to port PORT and the given IP address (usually 0.0.0.0 or ::) */
+    uint16_t *portptr = NULL;
+    struct sockaddr_storage addr;
+    size_t addrsize;
+#ifdef TOX_ENABLE_IPV6
+    if (temp->family == AF_INET)
+    {
+        IP4 ip4 = ip.ip4;
+#else
+        IP4 ip4 = ip;
+#endif
+        addrsize = sizeof(struct sockaddr_in);
+        struct sockaddr_in *addr4 = (struct sockaddr_in *)&addr;
+        addr4->sin_family = AF_INET;
+        addr4->sin_port = htons(port);
+        addr4->sin_addr = ip4.in_addr;
+
+        portptr = &addr4->sin_port;
+#ifdef TOX_ENABLE_IPV6
+    }
+    else if (temp->family == AF_INET6)
+    {
+        addrsize = sizeof(struct sockaddr_in6);
+        struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&addr;
+        addr6->sin6_family = AF_INET6;
+        addr6->sin6_port = htons(port);
+        addr6->sin6_addr = ip.ip6;
+
+        addr6->sin6_flowinfo = 0;
+        addr6->sin6_scope_id = 0;
+
+        portptr = &addr6->sin6_port;
+    }
+    else
+        return NULL;
+
+    if (ip.family == AF_INET6) {
+        char ipv6only = 0;
+        int res = setsockopt(temp->sock, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&ipv6only, sizeof(ipv6only));
+#ifdef LOGGING
+        if (res < 0) {
+            sprintf(logbuffer, "Failed to enable dual-stack on IPv6 socket, won't be able to receive from/send to IPv4 addresses. (%u, %s)\n",
+                    errno, strerror(errno));
+            loglog(logbuffer);
+        }
+        else
+            loglog("Embedded IPv4 addresses enabled successfully.\n");
+#endif
+
+        /* multicast local nodes */
+        struct ipv6_mreq mreq;
+        memset(&mreq, 0, sizeof(mreq));
+        mreq.ipv6mr_multiaddr.s6_addr[ 0] = 0xFF;
+        mreq.ipv6mr_multiaddr.s6_addr[ 1] = 0x02;
+        mreq.ipv6mr_multiaddr.s6_addr[15] = 0x01;
+        mreq.ipv6mr_interface = 0;
+        res = setsockopt(temp->sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
+#ifdef LOGGING
+        if (res < 0) {
+            sprintf(logbuffer, "Failed to activate local multicast membership. (%u, %s)\n",
+                    errno, strerror(errno));
+            loglog(logbuffer);
+        }
+        else
+            loglog("Local multicast group FF02::1 joined successfully.\n");
+#endif
+    }
+#endif
+
+    /* a hanging program or a different user might block the standard port;
+     * as long as it isn't a parameter coming from the commandline,
+     * try a few ports after it, to see if we can find a "free" one
+     */
+    int tries, res;
+    for(tries = 0; tries < 9; tries++)
+    {
+        res = bind(temp->sock, (struct sockaddr *)&addr, addrsize);
+        if (!res)
+        {
+            temp->port = *portptr;
+#ifdef LOGGING
+            sprintf(logbuffer, "Bound successfully to %s:%u.\n", ip_ntoa(&ip), ntohs(temp->port));
+            loglog(logbuffer);
+#endif
+            return temp;
+        }
+
+        uint16_t port = ntohs(*portptr);
+        port++;
+        *portptr = htons(port);
+    }
+
+    fprintf(stderr, "Failed to bind socket: %u, %s (IP/Port: %s:%u\n", errno,
+                    strerror(errno), ip_ntoa(&ip), port);
+    free(temp);
+    return NULL;
 }
 
 /* Function to cleanup networking stuff. */
@@ -235,3 +434,362 @@ void kill_networking(Networking_Core *net)
     free(net);
     return;
 }
+
+/* ip_equal
+ *  compares two IPAny structures
+ *  unset means unequal
+ *
+ * returns 0 when not equal or when uninitialized
+ */
+int ip_equal(IP *a, IP *b)
+{
+    if (!a || !b)
+        return 0;
+
+#ifdef TOX_ENABLE_IPV6
+    if (a->family == AF_INET)
+        return (a->ip4.in_addr.s_addr == b->ip4.in_addr.s_addr);
+
+    if (a->family == AF_INET6)
+        return IN6_ARE_ADDR_EQUAL(&a->ip6, &b->ip6);
+
+    return 0;
+#else
+    return (a->uint32 == b->uint32);
+#endif
+};
+
+/* ipport_equal
+ *  compares two IPAny_Port structures
+ *  unset means unequal
+ *
+ * returns 0 when not equal or when uninitialized
+ */
+int ipport_equal(IP_Port *a, IP_Port *b)
+{
+    if (!a || !b)
+        return 0;
+
+    if (!a->port || (a->port != b->port))
+        return 0;
+
+    return ip_equal(&a->ip, &b->ip);
+};
+
+/* nulls out ip */
+void ip_reset(IP *ip)
+{
+    if (!ip)
+        return;
+
+#ifdef TOX_ENABLE_IPV6
+    memset(ip, 0, sizeof(IP));
+#else
+    ip->uint32 = 0;
+#endif
+};
+
+/* nulls out ip, sets family according to flag */
+void ip_init(IP *ip, uint8_t ipv6enabled)
+{
+    if (!ip)
+        return;
+
+#ifdef TOX_ENABLE_IPV6
+    memset(ip, 0, sizeof(IP));
+    ip->family = ipv6enabled ? AF_INET6 : AF_INET;
+#else
+    ip->uint32 = 0;
+#endif
+};
+
+/* checks if ip is valid */
+int ip_isset(IP *ip)
+{
+    if (!ip)
+        return 0;
+
+#ifdef TOX_ENABLE_IPV6
+    return (ip->family != 0);
+#else
+    return (ip->uint32 != 0);
+#endif
+};
+
+/* checks if ip is valid */
+int ipport_isset(IP_Port *ipport)
+{
+    if (!ipport)
+        return 0;
+
+    if (!ipport->port)
+        return 0;
+
+    return ip_isset(&ipport->ip);
+};
+
+/* copies an ip structure (careful about direction!) */
+void ip_copy(IP *target, IP *source)
+{
+    if (!source || !target)
+        return;
+
+    memcpy(target, source, sizeof(IP));
+};
+
+/* copies an ip_port structure (careful about direction!) */
+void ipport_copy(IP_Port *target, IP_Port *source)
+{
+    if (!source || !target)
+        return;
+
+    memcpy(target, source, sizeof(IP_Port));
+};
+
+/* ip_ntoa
+ *   converts ip into a string
+ *   uses a static buffer, so mustn't used multiple times in the same output
+ */
+/* there would be INET6_ADDRSTRLEN, but it might be too short for the error message */
+static char addresstext[96];
+const char *ip_ntoa(IP *ip)
+{
+    if (ip) {
+#ifdef TOX_ENABLE_IPV6
+        if (ip->family == AF_INET) {
+            addresstext[0] = 0;
+            struct in_addr *addr = (struct in_addr *)&ip->ip4;
+            inet_ntop(ip->family, addr, addresstext, sizeof(addresstext));
+        }
+        else if (ip->family == AF_INET6) {
+            addresstext[0] = '[';
+            struct in6_addr *addr = (struct in6_addr *)&ip->ip6;
+            inet_ntop(ip->family, addr, &addresstext[1], sizeof(addresstext) - 3);
+            size_t len = strlen(addresstext);
+            addresstext[len] = ']';
+            addresstext[len + 1] = 0;
+        }
+        else
+            snprintf(addresstext, sizeof(addresstext), "(IP invalid, family %u)", ip->family);
+#else
+        addresstext[0] = 0;
+        struct in_addr *addr = (struct in_addr *)&ip;
+        inet_ntop(AF_INET, addr, addresstext, sizeof(addresstext));
+#endif
+    }
+    else
+        snprintf(addresstext, sizeof(addresstext), "(IP invalid: NULL)");
+
+    addresstext[INET6_ADDRSTRLEN + 2] = 0;
+    return addresstext;
+};
+
+/*
+ * addr_parse_ip
+ *  directly parses the input into an IP structure
+ *  tries IPv4 first, then IPv6
+ *
+ * input
+ *  address: dotted notation (IPv4: quad, IPv6: 16) or colon notation (IPv6)
+ *
+ * output
+ *  IP: family and the value is set on success
+ *
+ * returns 1 on success, 0 on failure
+ */
+
+int addr_parse_ip(const char *address, IP *to)
+{
+    if (!address || !to)
+        return 0;
+
+#ifdef TOX_ENABLE_IPV6
+    struct in_addr addr4;
+    if (1 == inet_pton(AF_INET, address, &addr4)) {
+        to->family = AF_INET;
+        to->ip4.in_addr = addr4;
+        return 1;
+    };
+
+    struct in6_addr addr6;
+    if (1 == inet_pton(AF_INET6, address, &addr6)) {
+        to->family = AF_INET6;
+        to->ip6 = addr6;
+        return 1;
+    };
+#else
+    struct in_addr addr4;
+    if (1 == inet_pton(AF_INET, address, &addr4)) {
+        to->in_addr = addr4;
+        return 1;
+    };
+#endif
+
+    return 0;
+};
+
+/*
+ * addr_resolve():
+ *  uses getaddrinfo to resolve an address into an IP address
+ *  uses the first IPv4/IPv6 addresses returned by getaddrinfo
+ *
+ * input
+ *  address: a hostname (or something parseable to an IP address)
+ *  ip: ip.family MUST be initialized, either set to a specific IP version
+ *     (AF_INET/AF_INET6) or to the unspecified AF_UNSPEC (= 0), if both
+ *     IP versions are acceptable
+ *
+ * returns in ip a valid IPAny (v4/v6),
+ *     prefers v6 if ip.family was AF_UNSPEC and both available
+ * returns 0 on failure
+ */
+
+int addr_resolve(const char *address, IP *to)
+{
+    if (!address || !to)
+        return 0;
+
+    sa_family_t family;
+#ifdef TOX_ENABLE_IPV6
+    family = to->family;
+#else
+    family = AF_INET;
+#endif
+
+    struct addrinfo *server = NULL;
+    struct addrinfo *walker = NULL;
+    struct addrinfo  hints;
+    int              rc;
+
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family   = family;
+    hints.ai_socktype = SOCK_DGRAM; // type of socket Tox uses.
+
+#ifdef __WIN32__
+    WSADATA wsa_data;
+
+    /* CLEANUP: really not the best place to put this */
+    rc = WSAStartup(MAKEWORD(2, 2), &wsa_data);
+
+    if (rc != 0) {
+        return 0;
+    }
+
+#endif
+
+    rc = getaddrinfo(address, NULL, &hints, &server);
+    // Lookup failed.
+    if (rc != 0) {
+#ifdef __WIN32__
+        WSACleanup();
+#endif
+        return 0;
+    }
+
+#ifdef TOX_ENABLE_IPV6
+    IP4 ip4;
+    memset(&ip4, 0, sizeof(ip4));
+    IP6 ip6;
+    memset(&ip6, 0, sizeof(ip6));
+#endif
+
+    walker = server;
+    while (walker && (rc != 3)) {
+        if (family != AF_UNSPEC) {
+            if (walker->ai_family == family) {
+                if (family == AF_INET) {
+                    if (walker->ai_addrlen == sizeof(struct sockaddr_in)) {
+                        struct sockaddr_in *addr = (struct sockaddr_in *)walker->ai_addr;
+#ifdef TOX_ENABLE_IPV6
+                        to->ip4.in_addr = addr->sin_addr;
+#else
+                        to->in_addr = addr->sin_addr;
+#endif
+                        rc = 3;
+                    }
+                }
+#ifdef TOX_ENABLE_IPV6
+                else if (family == AF_INET6) {
+                    if (walker->ai_addrlen == sizeof(struct sockaddr_in6)) {
+                        struct sockaddr_in6 *addr = (struct sockaddr_in6 *)walker->ai_addr;
+                        to->ip6 = addr->sin6_addr;
+                        rc = 3;
+                    }
+                }
+#endif
+            }
+        }
+#ifdef TOX_ENABLE_IPV6
+        else {
+            if (walker->ai_family == AF_INET) {
+                if (walker->ai_addrlen == sizeof(struct sockaddr_in)) {
+                    struct sockaddr_in *addr = (struct sockaddr_in *)walker->ai_addr;
+                    ip4.in_addr = addr->sin_addr;
+                    rc |= 1;
+                }
+            }
+            else if (walker->ai_family == AF_INET6) {
+                if (walker->ai_addrlen == sizeof(struct sockaddr_in6)) {
+                    struct sockaddr_in6 *addr = (struct sockaddr_in6 *)walker->ai_addr;
+                    ip6 = addr->sin6_addr;
+                    rc |= 2;
+                }
+            }
+        }
+#endif
+
+        walker = walker->ai_next;
+    }
+
+#ifdef TOX_ENABLE_IPV6
+    if (to->family == AF_UNSPEC) {
+        if (rc & 2) {
+            to->family = AF_INET6;
+            to->ip6 = ip6;
+        }
+        else if (rc & 1) {
+            to->family = AF_INET;
+            to->ip4 = ip4;
+        }
+        else
+            rc = 0;
+    }
+#endif
+
+    
+    freeaddrinfo(server);
+#ifdef __WIN32__
+    WSACleanup();
+#endif
+    return rc;
+}
+
+/*
+ * addr_resolve_or_parse_ip
+ *  resolves string into an IP address
+ *
+ * to->family MUST be set (AF_UNSPEC, AF_INET, AF_INET6)
+ * returns 1 on success, 0 on failure
+ */
+int addr_resolve_or_parse_ip(const char *address, IP *to)
+{
+    if (!addr_resolve(address, to))
+        if (!addr_parse_ip(address, to))
+            return 0;
+
+    return 1;
+};
+
+#ifdef LOGGING
+static void loglogdata(char *message, uint8_t *buffer, size_t buflen, IP_Port *ip_port, ssize_t res)
+{
+    snprintf(logbuffer, sizeof(logbuffer), "[%2u] %3u%c %s %s:%u (%u: %s) | %04x%04x\n",
+        buffer[0], res < 0 ? (buflen & 0xFF) : res,
+        res < 0 ? '-' : (res == buflen ? '=' : '+'),
+        message, ip_ntoa(&ip_port->ip), ntohs(ip_port->port), res < 0 ? errno : 0,
+        res < 0 ? strerror(errno) : "OK", buflen > 4 ? ntohl(*(uint32_t *)&buffer[1]) : 0,
+        buflen > 7 ? ntohl(*(uint32_t *)(&buffer[5])) : 0);
+    logbuffer[sizeof(logbuffer) - 1] = 0;
+    loglog(logbuffer);
+}
+#endif
diff --git a/toxcore/network.h b/toxcore/network.h
index 2d08e88d..e804379d 100644
--- a/toxcore/network.h
+++ b/toxcore/network.h
@@ -39,17 +39,22 @@
 #include <windows.h>
 #include <ws2tcpip.h>
 
+typedef unsigned int sock_t;
+
 #else // Linux includes
 
 #include <fcntl.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
+#include <arpa/inet.h>
 #include <errno.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <netdb.h>
 #include <unistd.h>
 
+typedef int sock_t;
+
 #endif
 
 #ifndef VANILLA_NACL
@@ -66,7 +71,8 @@
 #define NET_PACKET_PING_REQUEST    0   /* Ping request packet ID. */
 #define NET_PACKET_PING_RESPONSE   1   /* Ping response packet ID. */
 #define NET_PACKET_GET_NODES       2   /* Get nodes request packet ID. */
-#define NET_PACKET_SEND_NODES      3   /* Send nodes response packet ID. */
+#define NET_PACKET_SEND_NODES      3   /* Send nodes response packet ID for IPv4 addresses. */
+#define NET_PACKET_SEND_NODES_EX   4   /* Send nodes response packet ID for other addresses. */
 #define NET_PACKET_HANDSHAKE       16  /* Handshake packet ID. */
 #define NET_PACKET_SYNC            17  /* SYNC packet ID. */
 #define NET_PACKET_DATA            18  /* Data packet ID. */
@@ -82,27 +88,83 @@ typedef union {
     uint8_t uint8[4];
     uint16_t uint16[2];
     uint32_t uint32;
-} IP;
+    struct in_addr in_addr;
+} IP4;
+
+typedef struct in6_addr IP6;
+
+typedef struct {
+    sa_family_t family;
+    union {
+        IP4 ip4;
+        IP6 ip6;
+    };
+} IPAny;
 
 typedef union {
     struct {
-        IP ip;
+        IP4 ip;
         uint16_t port;
         /* Not used for anything right now. */
         uint16_t padding;
     };
     uint8_t uint8[8];
-} IP_Port;
+} IP4_Port;
 
+/* will replace IP_Port as soon as the complete infrastructure is in place
+ * removed the unused union and padding also */
 typedef struct {
-    int16_t family;
+    IPAny ip;
     uint16_t port;
-    IP ip;
-    uint8_t zeroes[8];
-#ifdef ENABLE_IPV6
-    uint8_t zeroes2[12];
+} IPAny_Port;
+
+#undef TOX_ENABLE_IPV6
+/* #define TOX_ENABLE_IPV6 */
+#ifdef TOX_ENABLE_IPV6
+#define TOX_ENABLE_IPV6_DEFAULT 1
+typedef IPAny IP;
+typedef IPAny_Port IP_Port;
+#else
+#define TOX_ENABLE_IPV6_DEFAULT 0
+typedef IP4 IP;
+typedef IP4_Port IP_Port;
 #endif
-} ADDR;
+
+/* ip_ntoa
+ *   converts ip into a string
+ *   uses a static buffer, so mustn't used multiple times in the same output
+ */
+const char *ip_ntoa(IP *ip);
+
+/* ipport_equal
+ *  compares two IPAny_Port structures
+ *  unset means unequal
+ *
+ * returns 0 when not equal or when uninitialized
+ */
+int ipport_equal(IP_Port *a, IP_Port *b);
+
+/* nulls out ip */
+void ip_reset(IP *ip);
+/* nulls out ip, sets family according to flag */
+void ip_init(IP *ip, uint8_t ipv6enabled);
+/* checks if ip is valid */
+int ip_isset(IP *ip);
+/* checks if ip is valid */
+int ipport_isset(IP_Port *ipport);
+/* copies an ip structure */
+void ip_copy(IP *target, IP *source);
+/* copies an ip_port structure */
+void ipport_copy(IP_Port *target, IP_Port *source);
+
+/*
+ * addr_resolve_or_parse_ip
+ *  resolves string into an IP address
+ *
+ * to->family MUST be set (AF_UNSPEC, AF_INET, AF_INET6)
+ * returns 1 on success, 0 on failure
+ */
+int addr_resolve_or_parse_ip(const char *address, IP *to);
 
 /* Function to receive data, ip and port of sender is put into ip_port.
  * Packet data is put into data.
@@ -117,13 +179,11 @@ typedef struct {
 
 typedef struct {
     Packet_Handles packethandlers[256];
-    /* Our UDP socket. */
-#ifdef WIN32
-    unsigned int sock;
-#else
-    int sock;
-#endif
 
+    /* Our UDP socket. */
+    sa_family_t family;
+    uint16_t port;
+    sock_t sock;
 } Networking_Core;
 
 /*  return current time in milleseconds since the epoch. */
@@ -137,12 +197,7 @@ uint32_t random_int(void);
 /* Basic network functions: */
 
 /* Function to send packet(data) of length length to ip_port. */
-#ifdef WIN32
-int sendpacket(unsigned int sock, IP_Port ip_port, uint8_t *data, uint32_t length);
-#else
-int sendpacket(int sock, IP_Port ip_port, uint8_t *data, uint32_t length);
-#endif
-
+int sendpacket(Networking_Core *net, IP_Port ip_port, uint8_t *data, uint32_t length);
 
 /* Function to call when packet beginning with byte is received. */
 void networking_registerhandler(Networking_Core *net, uint8_t byte, packet_handler_callback cb, void *object);
@@ -163,5 +218,4 @@ Networking_Core *new_networking(IP ip, uint16_t port);
 /* Function to cleanup networking stuff (doesn't do much right now). */
 void kill_networking(Networking_Core *net);
 
-
 #endif
diff --git a/toxcore/ping.c b/toxcore/ping.c
index 3b39d911..49e0dba9 100644
--- a/toxcore/ping.c
+++ b/toxcore/ping.c
@@ -100,7 +100,8 @@ bool is_pinging(void *ping, IP_Port ipp, uint64_t ping_id)    // O(n) TODO: Repl
 {
     PING *png = ping;
 
-    if (ipp.ip.uint32 == 0 && ping_id == 0)
+    /* shouldn't that be an OR ? */
+    if (!ip_isset(&ipp.ip) && ping_id == 0)
         return false;
 
     size_t i, id;
@@ -111,7 +112,8 @@ bool is_pinging(void *ping, IP_Port ipp, uint64_t ping_id)    // O(n) TODO: Repl
         id = (png->pos_pings + i) % PING_NUM_MAX;
 
         /* ping_id = 0 means match any id. */
-        if ((ipp_eq(png->pings[id].ipp, ipp) || ipp.ip.uint32 == 0) && (png->pings[id].id == ping_id || ping_id == 0)) {
+        if ((!ip_isset(&ipp.ip) || ipport_equal(&png->pings[id].ipp, &ipp)) &&
+                            (png->pings[id].id == ping_id || ping_id == 0)) {
             return true;
         }
     }
@@ -147,7 +149,7 @@ int send_ping_request(void *ping, Net_Crypto *c, IP_Port ipp, uint8_t *client_id
     if (rc != sizeof(ping_id) + ENCRYPTION_PADDING)
         return 1;
 
-    return sendpacket(c->lossless_udp->net->sock, ipp, pk, sizeof(pk));
+    return sendpacket(c->lossless_udp->net, ipp, pk, sizeof(pk));
 }
 
 int send_ping_response(Net_Crypto *c, IP_Port ipp, uint8_t *client_id, uint64_t ping_id)
@@ -172,7 +174,7 @@ int send_ping_response(Net_Crypto *c, IP_Port ipp, uint8_t *client_id, uint64_t
     if (rc != sizeof(ping_id) + ENCRYPTION_PADDING)
         return 1;
 
-    return sendpacket(c->lossless_udp->net->sock, ipp, pk, sizeof(pk));
+    return sendpacket(c->lossless_udp->net, ipp, pk, sizeof(pk));
 }
 
 int handle_ping_request(void *object, IP_Port source, uint8_t *packet, uint32_t length)
diff --git a/toxcore/tox.c b/toxcore/tox.c
index 54bbd9f0..5e3893ec 100644
--- a/toxcore/tox.c
+++ b/toxcore/tox.c
@@ -374,6 +374,12 @@ void tox_bootstrap(void *tox, IP_Port ip_port, uint8_t *public_key)
     Messenger *m = tox;
     DHT_bootstrap(m->dht, ip_port, public_key);
 }
+int tox_bootstrap_ex(void *tox, const char *address, uint8_t ipv6enabled,
+                      uint16_t port, uint8_t *public_key)
+{
+    Messenger *m = tox;
+    return DHT_bootstrap_ex(m->dht, address, ipv6enabled, port, public_key);
+};
 
 /*  return 0 if we are not connected to the DHT.
  *  return 1 if we are.
@@ -389,9 +395,13 @@ int tox_isconnected(void *tox)
  *  return allocated instance of tox on success.
  *  return 0 if there are problems.
  */
+void *tox_new_ex(uint8_t ipv6enabled)
+{
+    return initMessenger(ipv6enabled);
+}
 void *tox_new(void)
 {
-    return initMessenger();
+    return tox_new_ex(0);
 }
 
 /* Run this before closing shop.
diff --git a/toxcore/tox.h b/toxcore/tox.h
index 811e798b..cf5d6b2a 100644
--- a/toxcore/tox.h
+++ b/toxcore/tox.h
@@ -26,6 +26,22 @@
 
 #include <stdint.h>
 
+#ifdef WIN32
+#ifndef WINVER
+//Windows XP
+#define WINVER 0x0501
+#endif
+
+#include <winsock2.h>
+#include <windows.h>
+#include <ws2tcpip.h>
+
+#else
+
+#include <netinet/ip.h>
+
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -36,19 +52,52 @@ extern "C" {
 
 #define TOX_FRIEND_ADDRESS_SIZE (TOX_CLIENT_ID_SIZE + sizeof(uint32_t) + sizeof(uint16_t))
 
-
 typedef union {
     uint8_t c[4];
     uint16_t s[2];
     uint32_t i;
-} tox_IP;
+} tox_IP4;
+
+
+typedef struct in6_addr tox_IP6;
 
 typedef struct {
-    tox_IP ip;
+    sa_family_t family;
+    union {
+        tox_IP4 ip4;
+        tox_IP6 ip6;
+    };
+} tox_IPAny;
+
+typedef union {
+    struct {
+        tox_IP4 ip;
+        uint16_t port;
+        /* Not used for anything right now. */
+        uint16_t padding;
+    };
+    uint8_t uint8[8];
+} tox_IP4_Port;
+
+/* will replace IP_Port as soon as the complete infrastructure is in place
+ * removed the unused union and padding also */
+typedef struct {
+    tox_IPAny ip;
     uint16_t port;
-    /* Not used for anything right now. */
-    uint16_t padding;
-} tox_IP_Port;
+} tox_IPAny_Port;
+
+#undef TOX_ENABLE_IPV6
+/* #define TOX_ENABLE_IPV6 */
+#ifdef TOX_ENABLE_IPV6
+#define TOX_ENABLE_IPV6_DEFAULT 1
+typedef tox_IPAny tox_IP;
+typedef tox_IPAny_Port tox_IP_Port;
+#else
+#define TOX_ENABLE_IPV6_DEFAULT 0
+typedef tox_IP4 tox_IP;
+typedef tox_IP4_Port tox_IP_Port;
+#endif
+
 
 /* Errors for m_addfriend
  * FAERR - Friend Add Error
@@ -291,8 +340,11 @@ void tox_callback_connectionstatus(Tox *tox, void (*function)(Tox *tox, int, uin
 
 /* Use this function to bootstrap the client.
  * Sends a get nodes request to the given node with ip port and public_key.
+ * tox_bootstrap_ex() returns 1 if the address could be converted, 0 otherwise
  */
 void tox_bootstrap(Tox *tox, tox_IP_Port ip_port, uint8_t *public_key);
+int tox_bootstrap_ex(Tox *tox, const char *address, uint8_t ipv6enabled,
+                      uint16_t port, uint8_t *public_key);
 
 /*  return 0 if we are not connected to the DHT.
  *  return 1 if we are.
@@ -305,6 +357,7 @@ int tox_isconnected(Tox *tox);
  *  return 0 if there are problems.
  */
 Tox *tox_new(void);
+Tox *tox_new_ex(uint8_t ipv6enabled);
 
 /* Run this before closing shop.
  * Free all datastructures. */
diff --git a/toxcore/util.c b/toxcore/util.c
index 1728ea21..7b5ddc49 100644
--- a/toxcore/util.c
+++ b/toxcore/util.c
@@ -10,11 +10,12 @@
 #endif
 
 #include <time.h>
-#include <stdint.h>
-#include <stdbool.h>
 
+/* for CLIENT_ID_SIZE */
 #include "DHT.h"
 
+#include "util.h"
+
 uint64_t now()
 {
     return time(NULL);
@@ -32,11 +33,6 @@ uint64_t random_64b()
     return r;
 }
 
-bool ipp_eq(IP_Port a, IP_Port b)
-{
-    return (a.ip.uint32 == b.ip.uint32) && (a.port == b.port);
-}
-
 bool id_eq(uint8_t *dest, uint8_t *src)
 {
     return memcmp(dest, src, CLIENT_ID_SIZE) == 0;
@@ -46,3 +42,62 @@ void id_cpy(uint8_t *dest, uint8_t *src)
 {
     memcpy(dest, src, CLIENT_ID_SIZE);
 }
+
+int cmdline_parsefor_ipv46(int argc, char **argv, uint8_t *ipv6enabled)
+{
+    int argvoffset = 0, argi;
+    for(argi = 1; argi < argc; argi++)
+        if (!strncasecmp(argv[argi], "--ipv", 5)) {
+            if (argv[argi][5] && !argv[argi][6]) {
+                char c = argv[argi][5];
+                if (c == '4')
+                    *ipv6enabled = 0;
+                else if (c == '6')
+                    *ipv6enabled = 1;
+                else {
+                    printf("Invalid argument: %s. Try --ipv4 or --ipv6!\n", argv[argi]);
+                    return -1;
+                }
+            }
+            else {
+                printf("Invalid argument: %s. Try --ipv4 or --ipv6!\n", argv[argi]);
+                return -1;
+            }
+
+            if (argvoffset != argi - 1) {
+                printf("Argument must come first: %s.\n", argv[argi]);
+                return -1;
+            }
+
+            argvoffset++;
+        }
+
+    return argvoffset;
+};
+
+#ifdef LOGGING
+char logbuffer[512];
+static FILE *logfile = NULL;
+void loginit(uint16_t port)
+{
+    if (logfile)
+        fclose(logfile);
+
+    sprintf(logbuffer, "%u-%u.log", ntohs(port), now);
+    logfile = fopen(logbuffer, "w");
+};
+void loglog(char *text)
+{
+    if (logfile) {
+        fprintf(logfile, text);
+        fflush(logfile);
+    }
+};
+void logexit()
+{
+    if (logfile) {
+        fclose(logfile);
+        logfile = NULL;
+    }
+};
+#endif
diff --git a/toxcore/util.h b/toxcore/util.h
index 90a3c8e4..e7be2d51 100644
--- a/toxcore/util.h
+++ b/toxcore/util.h
@@ -5,8 +5,26 @@
  * Copyright 2013  plutooo
  */
 
+#ifndef __UTIL_H__
+#define __UTIL_H__
+
+#include <stdbool.h>
+#include <stdint.h>
+
 uint64_t now();
 uint64_t random_64b();
-bool ipp_eq(IP_Port a, IP_Port b);
 bool id_eq(uint8_t *dest, uint8_t *src);
 void id_cpy(uint8_t *dest, uint8_t *src);
+
+int cmdline_parsefor_ipv46(int argc, char **argv, uint8_t *ipv6enabled);
+
+#undef LOGGING
+/* #define LOGGING */
+#ifdef LOGGING
+extern char logbuffer[512];
+void loginit(uint16_t port);
+void loglog(char *text);
+void logexit();
+#endif
+
+#endif /* __UTIL_H__ */