cleanup: clarify and isolate use of custom IP_Port values to denote T…

…CP connections

toxcore/TCP_connection.c

@@ -486,6 +486,30 @@ void set_onion_packet_tcp_connection_callback(TCP_Connections *tcp_c, tcp_onion_
     tcp_c->tcp_onion_callback_object = object;
 }
 
+/** @brief Encode tcp_connections_number as a custom ip_port.
+ *
+ * return ip_port.
+ */
+IP_Port tcp_connections_number_to_ip_port(unsigned int tcp_connections_number)
+{
+    IP_Port ip_port = {{{0}}};
+    ip_port.ip.family = net_family_tcp_server;
+    ip_port.ip.ip.v6.uint32[0] = tcp_connections_number;
+    return ip_port;
+}
+
+/** @brief Decode ip_port created by tcp_connections_number_to_ip_port to tcp_connections_number.
+ *
+ * return true on success.
+ * return false if ip_port is invalid.
+ */
+non_null()
+bool ip_port_to_tcp_connections_number(const IP_Port *ip_port, unsigned int *tcp_connections_number)
+{
+    *tcp_connections_number = ip_port->ip.ip.v6.uint32[0];
+    return net_family_is_tcp_server(ip_port->ip.family);
+}
+
 /** @brief Find the TCP connection with public_key.
  *
  * return connections_number on success.

toxcore/TCP_connection.h

@@ -153,6 +153,20 @@ typedef int tcp_oob_cb(void *object, const uint8_t *public_key, unsigned int tcp
 non_null()
 void set_oob_packet_tcp_connection_callback(TCP_Connections *tcp_c, tcp_oob_cb *tcp_oob_callback, void *object);
 
+/** @brief Encode tcp_connections_number as a custom ip_port.
+ *
+ * return ip_port.
+ */
+IP_Port tcp_connections_number_to_ip_port(unsigned int tcp_connections_number);
+
+/** @brief Decode ip_port created by tcp_connections_number_to_ip_port to tcp_connections_number.
+ *
+ * return true on success.
+ * return false if ip_port is invalid.
+ */
+non_null()
+bool ip_port_to_tcp_connections_number(const IP_Port *ip_port, unsigned int *tcp_connections_number);
+
 /** @brief Create a new TCP connection to public_key.
  *
  * public_key must be the counterpart to the secret key that the other peer used with `new_tcp_connections()`.

toxcore/TCP_server.c

@@ -566,22 +566,47 @@ static int rm_connection_index(TCP_Server *tcp_server, TCP_Secure_Connection *co
     return -1;
 }
 
+/* Encode con_id and identifier as a custom IP_Port.
+ *
+ * return ip_port.
+ */
+static IP_Port con_id_to_ip_port(uint32_t con_id, uint64_t identifier)
+{
+    IP_Port ip_port = {{{0}}};
+    ip_port.ip.family = net_family_tcp_client;
+    ip_port.ip.ip.v6.uint32[0] = con_id;
+    ip_port.ip.ip.v6.uint64[1] = identifier;
+    return ip_port;
+
+}
+
+/* Decode ip_port created by con_id_to_ip_port to con_id.
+ *
+ * return true on success.
+ * return false if ip_port is invalid.
+ */
+non_null()
+static bool ip_port_to_con_id(const TCP_Server *tcp_server, const IP_Port *ip_port, uint32_t *con_id)
+{
+    *con_id = ip_port->ip.ip.v6.uint32[0];
+
+    return (net_family_is_tcp_client(ip_port->ip.family) &&
+            *con_id < tcp_server->size_accepted_connections &&
+            tcp_server->accepted_connection_array[*con_id].identifier == ip_port->ip.ip.v6.uint64[1]);
+}
+
 non_null()
 static int handle_onion_recv_1(void *object, const IP_Port *dest, const uint8_t *data, uint16_t length)
 {
     TCP_Server *tcp_server = (TCP_Server *)object;
-    const uint32_t index = dest->ip.ip.v6.uint32[0];
+    uint32_t index;
 
-    if (index >= tcp_server->size_accepted_connections) {
+    if (!ip_port_to_con_id(tcp_server, dest, &index)) {
         return 1;
     }
 
     TCP_Secure_Connection *con = &tcp_server->accepted_connection_array[index];
 
-    if (con->identifier != dest->ip.ip.v6.uint64[1]) {
-        return 1;
-    }
-
     VLA(uint8_t, packet, 1 + length);
     memcpy(packet + 1, data, length);
     packet[0] = TCP_PACKET_ONION_RESPONSE;
@@ -688,12 +713,7 @@ static int handle_TCP_packet(TCP_Server *tcp_server, uint32_t con_id, const uint
                     return -1;
                 }
 
-                IP_Port source;
-                source.port = 0;  // dummy initialise
-                source.ip.family = net_family_tcp_onion;
-                source.ip.ip.v6.uint32[0] = con_id;
-                source.ip.ip.v6.uint32[1] = 0;
-                source.ip.ip.v6.uint64[1] = con->identifier;
+                IP_Port source = con_id_to_ip_port(con_id, con->identifier);
                 onion_send_1(tcp_server->onion, data + 1 + CRYPTO_NONCE_SIZE, length - (1 + CRYPTO_NONCE_SIZE), &source,
                              data + 1);
             }

toxcore/net_crypto.c

@@ -1983,8 +1983,10 @@ static int crypto_connection_add_source(Net_Crypto *c, int crypt_connection_id,
         return 0;
     }
 
-    if (net_family_is_tcp_family(source->ip.family)) {
-        if (add_tcp_number_relay_connection(c->tcp_c, conn->connection_number_tcp, source->ip.ip.v6.uint32[0]) == 0) {
+    unsigned int tcp_connections_number;
+
+    if (ip_port_to_tcp_connections_number(source, &tcp_connections_number)) {
+        if (add_tcp_number_relay_connection(c->tcp_c, conn->connection_number_tcp, tcp_connections_number) == 0) {
             return 1;
         }
     }
@@ -2268,10 +2270,7 @@ static int tcp_oob_callback(void *object, const uint8_t *public_key, unsigned in
     }
 
     if (data[0] == NET_PACKET_CRYPTO_HS) {
-        IP_Port source;
-        source.port = 0;
-        source.ip.family = net_family_tcp_family;
-        source.ip.ip.v6.uint32[0] = tcp_connections_number;
+        IP_Port source = tcp_connections_number_to_ip_port(tcp_connections_number);
 
         if (handle_new_connection_handshake(c, &source, data, length, userdata) != 0) {
             return -1;

toxcore/network.c

@@ -371,8 +371,8 @@ const Socket net_invalid_socket = { (int)INVALID_SOCKET };
 const Family net_family_unspec = {TOX_AF_UNSPEC};
 const Family net_family_ipv4 = {TOX_AF_INET};
 const Family net_family_ipv6 = {TOX_AF_INET6};
-const Family net_family_tcp_family = {TCP_FAMILY};
-const Family net_family_tcp_onion = {TCP_ONION_FAMILY};
+const Family net_family_tcp_server = {TCP_SERVER_FAMILY};
+const Family net_family_tcp_client = {TCP_CLIENT_FAMILY};
 const Family net_family_tcp_ipv4 = {TCP_INET};
 const Family net_family_tcp_ipv6 = {TCP_INET6};
 const Family net_family_tox_tcp_ipv4 = {TOX_TCP_INET};
@@ -393,14 +393,14 @@ bool net_family_is_ipv6(Family family)
     return family.value == net_family_ipv6.value;
 }
 
-bool net_family_is_tcp_family(Family family)
+bool net_family_is_tcp_server(Family family)
 {
-    return family.value == net_family_tcp_family.value;
+    return family.value == net_family_tcp_server.value;
 }
 
-bool net_family_is_tcp_onion(Family family)
+bool net_family_is_tcp_client(Family family)
 {
-    return family.value == net_family_tcp_onion.value;
+    return family.value == net_family_tcp_client.value;
 }
 
 bool net_family_is_tcp_ipv4(Family family)

toxcore/network.h

@@ -77,8 +77,8 @@ typedef struct Family {
 bool net_family_is_unspec(Family family);
 bool net_family_is_ipv4(Family family);
 bool net_family_is_ipv6(Family family);
-bool net_family_is_tcp_family(Family family);
-bool net_family_is_tcp_onion(Family family);
+bool net_family_is_tcp_server(Family family);
+bool net_family_is_tcp_client(Family family);
 bool net_family_is_tcp_ipv4(Family family);
 bool net_family_is_tcp_ipv6(Family family);
 bool net_family_is_tox_tcp_ipv4(Family family);
@@ -87,8 +87,8 @@ bool net_family_is_tox_tcp_ipv6(Family family);
 extern const Family net_family_unspec;
 extern const Family net_family_ipv4;
 extern const Family net_family_ipv6;
-extern const Family net_family_tcp_family;
-extern const Family net_family_tcp_onion;
+extern const Family net_family_tcp_server;
+extern const Family net_family_tcp_client;
 extern const Family net_family_tcp_ipv4;
 extern const Family net_family_tcp_ipv6;
 extern const Family net_family_tox_tcp_ipv4;
@@ -195,10 +195,10 @@ typedef enum Net_Packet_Type {
 #define TOX_PROTO_UDP 2
 
 /** TCP related */
-#define TCP_ONION_FAMILY (TOX_AF_INET6 + 1)
+#define TCP_CLIENT_FAMILY (TOX_AF_INET6 + 1)
 #define TCP_INET (TOX_AF_INET6 + 2)
 #define TCP_INET6 (TOX_AF_INET6 + 3)
-#define TCP_FAMILY (TOX_AF_INET6 + 4)
+#define TCP_SERVER_FAMILY (TOX_AF_INET6 + 4)
 
 #define SIZE_IP4 4
 #define SIZE_IP6 16

toxcore/onion_client.c

@@ -291,8 +291,7 @@ static uint16_t random_nodes_path_onion(const Onion_Client *onion_c, Node_format
 
         if (num_nodes >= 2) {
             nodes[0] = empty_node_format;
-            nodes[0].ip_port.ip.family = net_family_tcp_family;
-            nodes[0].ip_port.ip.ip.v4.uint32 = random_tcp;
+            nodes[0].ip_port = tcp_connections_number_to_ip_port(random_tcp);
 
             for (unsigned int i = 1; i < max_num; ++i) {
                 const uint32_t rand_idx = random_range_u32(onion_c->rng, num_nodes);
@@ -306,8 +305,7 @@ static uint16_t random_nodes_path_onion(const Onion_Client *onion_c, Node_format
             }
 
             nodes[0] = empty_node_format;
-            nodes[0].ip_port.ip.family = net_family_tcp_family;
-            nodes[0].ip_port.ip.ip.v4.uint32 = random_tcp;
+            nodes[0].ip_port = tcp_connections_number_to_ip_port(random_tcp);
 
             for (unsigned int i = 1; i < max_num; ++i) {
                 const uint32_t rand_idx = random_range_u32(onion_c->rng, num_nodes_bs);
@@ -492,15 +490,17 @@ static int send_onion_packet_tcp_udp(const Onion_Client *onion_c, const Onion_Pa
         return 0;
     }
 
-    if (net_family_is_tcp_family(path->ip_port1.ip.family)) {
+    unsigned int tcp_connections_number;
+
+    if (ip_port_to_tcp_connections_number(&path->ip_port1, &tcp_connections_number)) {
         uint8_t packet[ONION_MAX_PACKET_SIZE];
         const int len = create_onion_packet_tcp(onion_c->rng, packet, sizeof(packet), path, dest, data, length);
 
         if (len == -1) {
             return -1;
         }
 
-        return send_tcp_onion_request(onion_c->c, path->ip_port1.ip.ip.v4.uint32, packet, len);
+        return send_tcp_onion_request(onion_c->c, tcp_connections_number, packet, len);
     }
 
     return -1;
@@ -1042,7 +1042,7 @@ static int handle_tcp_onion(void *object, const uint8_t *data, uint16_t length,
     }
 
     IP_Port ip_port = {{{0}}};
-    ip_port.ip.family = net_family_tcp_family;
+    ip_port.ip.family = net_family_tcp_server;
 
     if (data[0] == NET_PACKET_ANNOUNCE_RESPONSE_OLD) {
         return handle_announce_response(object, &ip_port, data, length, userdata);
@@ -1548,6 +1548,7 @@ static void populate_path_nodes_tcp(Onion_Client *onion_c)
     const unsigned int num_nodes = copy_connected_tcp_relays(onion_c->c, node_list, MAX_SENT_NODES);
 
     for (unsigned int i = 0; i < num_nodes; ++i) {
+        // XXX: but ip_port is TCP, so will be rejected by onion_add_bs_path_node...
         onion_add_bs_path_node(onion_c, &node_list[i].ip_port, node_list[i].public_key);
     }
 }