Changeset 89c57b6 in mainline for uspace/srv/net/tl/udp/udp.c

Timestamp:

2011-04-13T14:45:41Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

88634420

Parents:

cefb126 (diff), 17279ead (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge mainline changes.

File:

• uspace/srv/net/tl/udp/udp.c (modified) (3 diffs)

uspace/srv/net/tl/udp/udp.c

@@ -28 +28 @@
 
 /** @addtogroup udp
- *  @{
+ * @{
  */
 
 /** @file
- *  UDP module implementation.
- *  @see udp.h
+ * UDP module implementation.
+ * @see udp.h
  */
 
@@ -40 +40 @@
 #include <malloc.h>
 #include <stdio.h>
-#include <ipc/ipc.h>
 #include <ipc/services.h>
-
-#include <net_err.h>
-#include <net_messages.h>
-#include <net_modules.h>
+#include <ipc/net.h>
+#include <ipc/tl.h>
+#include <ipc/socket.h>
 #include <adt/dynamic_fifo.h>
-#include <packet/packet_client.h>
+#include <errno.h>
+
+#include <net/socket_codes.h>
+#include <net/ip_protocols.h>
+#include <net/in.h>
+#include <net/in6.h>
+#include <net/inet.h>
+#include <net/modules.h>
+
+#include <packet_client.h>
 #include <packet_remote.h>
 #include <net_checksum.h>
-#include <in.h>
-#include <in6.h>
-#include <inet.h>
 #include <ip_client.h>
 #include <ip_interface.h>
-#include <ip_protocols.h>
 #include <icmp_client.h>
-#include <icmp_interface.h>
+#include <icmp_remote.h>
 #include <net_interface.h>
-#include <socket_codes.h>
-#include <socket_errno.h>
 #include <socket_core.h>
-#include <socket_messages.h>
 #include <tl_common.h>
-#include <tl_local.h>
-#include <tl_interface.h>
-#include <tl_messages.h>
+#include <tl_remote.h>
+#include <tl_skel.h>
 
 #include "udp.h"
 #include "udp_header.h"
-#include "udp_module.h"
-
-/** UDP module name.
- */
-#define NAME    "UDP protocol"
-
-/** Default UDP checksum computing.
- */
+
+/** UDP module name. */
+#define NAME  "udp"
+
+/** Default UDP checksum computing. */
 #define NET_DEFAULT_UDP_CHECKSUM_COMPUTING      true
 
-/** Default UDP autobind when sending via unbound sockets.
- */
+/** Default UDP autobind when sending via unbound sockets. */
 #define NET_DEFAULT_UDP_AUTOBINDING     true
 
-/** Maximum UDP fragment size.
- */
-#define MAX_UDP_FRAGMENT_SIZE   65535
-
-/** Free ports pool start.
- */
-#define UDP_FREE_PORTS_START    1025
-
-/** Free ports pool end.
- */
+/** Maximum UDP fragment size. */
+#define MAX_UDP_FRAGMENT_SIZE           65535
+
+/** Free ports pool start. */
+#define UDP_FREE_PORTS_START            1025
+
+/** Free ports pool end. */
 #define UDP_FREE_PORTS_END              65535
 
+/** UDP global data.  */
+udp_globals_t udp_globals;
+
+/** Releases the packet and returns the result.
+ *
+ * @param[in] packet    The packet queue to be released.
+ * @param[in] result    The result to be returned.
+ * @return              The result parameter.
+ */
+static int udp_release_and_return(packet_t *packet, int result)
+{
+        pq_release_remote(udp_globals.net_phone, packet_get_id(packet));
+        return result;
+}
+
 /** Processes the received UDP packet queue.
- *  Is used as an entry point from the underlying IP module.
- *  Locks the global lock and calls udp_process_packet() function.
- *  @param[in] device_id The receiving device identifier.
- *  @param[in,out] packet The received packet queue.
- *  @param receiver The target service. Ignored parameter.
- *  @param[in] error The packet error reporting service. Prefixes the received packet.
- *  @returns EOK on success.
- *  @returns Other error codes as defined for the udp_process_packet() function.
- */
-int udp_received_msg(device_id_t device_id, packet_t packet, services_t receiver, services_t error);
+ *
+ * Notifies the destination socket application.
+ * Releases the packet on error or sends an ICMP error notification.
+ *
+ * @param[in] device_id The receiving device identifier.
+ * @param[in,out] packet The received packet queue.
+ * @param[in] error     The packet error reporting service. Prefixes the
+ *                      received packet.
+ * @return              EOK on success.
+ * @return              EINVAL if the packet is not valid.
+ * @return              EINVAL if the stored packet address is not the
+ *                      an_addr_t.
+ * @return              EINVAL if the packet does not contain any data.
+ * @return              NO_DATA if the packet content is shorter than the user
+ *                      datagram header.
+ * @return              ENOMEM if there is not enough memory left.
+ * @return              EADDRNOTAVAIL if the destination socket does not exist.
+ * @return              Other error codes as defined for the
+ *                      ip_client_process_packet() function.
+ */
+static int udp_process_packet(device_id_t device_id, packet_t *packet,
+    services_t error)
+{
+        size_t length;
+        size_t offset;
+        int result;
+        udp_header_t *header;
+        socket_core_t *socket;
+        packet_t *next_packet;
+        size_t total_length;
+        uint32_t checksum;
+        int fragments;
+        packet_t *tmp_packet;
+        icmp_type_t type;
+        icmp_code_t code;
+        void *ip_header;
+        struct sockaddr *src;
+        struct sockaddr *dest;
+        packet_dimension_t *packet_dimension;
+        int rc;
+
+        switch (error) {
+        case SERVICE_NONE:
+                break;
+        case SERVICE_ICMP:
+                /* Ignore error */
+                // length = icmp_client_header_length(packet);
+
+                /* Process error */
+                result = icmp_client_process_packet(packet, &type,
+                    &code, NULL, NULL);
+                if (result < 0)
+                        return udp_release_and_return(packet, result);
+                length = (size_t) result;
+                rc = packet_trim(packet, length, 0);
+                if (rc != EOK)
+                        return udp_release_and_return(packet, rc);
+                break;
+        default:
+                return udp_release_and_return(packet, ENOTSUP);
+        }
+
+        /* TODO process received ipopts? */
+        result = ip_client_process_packet(packet, NULL, NULL, NULL, NULL, NULL);
+        if (result < 0)
+                return udp_release_and_return(packet, result);
+        offset = (size_t) result;
+
+        length = packet_get_data_length(packet);
+        if (length <= 0)
+                return udp_release_and_return(packet, EINVAL);
+        if (length < UDP_HEADER_SIZE + offset)
+                return udp_release_and_return(packet, NO_DATA);
+
+        /* Trim all but UDP header */
+        rc = packet_trim(packet, offset, 0);
+        if (rc != EOK)
+                return udp_release_and_return(packet, rc);
+
+        /* Get UDP header */
+        header = (udp_header_t *) packet_get_data(packet);
+        if (!header)
+                return udp_release_and_return(packet, NO_DATA);
+
+        /* Find the destination socket */
+        socket = socket_port_find(&udp_globals.sockets,
+            ntohs(header->destination_port), (uint8_t *) SOCKET_MAP_KEY_LISTENING, 0);
+        if (!socket) {
+                if (tl_prepare_icmp_packet(udp_globals.net_phone,
+                    udp_globals.icmp_phone, packet, error) == EOK) {
+                        icmp_destination_unreachable_msg(udp_globals.icmp_phone,
+                            ICMP_PORT_UNREACH, 0, packet);
+                }
+                return EADDRNOTAVAIL;
+        }
+
+        /* Count the received packet fragments */
+        next_packet = packet;
+        fragments = 0;
+        total_length = ntohs(header->total_length);
+
+        /* Compute header checksum if set */
+        if (header->checksum && !error) {
+                result = packet_get_addr(packet, (uint8_t **) &src,
+                    (uint8_t **) &dest);
+                if (result <= 0)
+                        return udp_release_and_return(packet, result);
+                
+                rc = ip_client_get_pseudo_header(IPPROTO_UDP, src, result, dest,
+                    result, total_length, &ip_header, &length);
+                if (rc != EOK) {
+                        return udp_release_and_return(packet, rc);
+                } else {
+                        checksum = compute_checksum(0, ip_header, length);
+                        /*
+                         * The udp header checksum will be added with the first
+                         * fragment later.
+                         */
+                        free(ip_header);
+                }
+        } else {
+                header->checksum = 0;
+                checksum = 0;
+        }
+
+        do {
+                fragments++;
+                length = packet_get_data_length(next_packet);
+                if (length <= 0)
+                        return udp_release_and_return(packet, NO_DATA);
+
+                if (total_length < length) {
+                        rc = packet_trim(next_packet, 0, length - total_length);
+                        if (rc != EOK)
+                                return udp_release_and_return(packet, rc);
+
+                        /* Add partial checksum if set */
+                        if (header->checksum) {
+                                checksum = compute_checksum(checksum,
+                                    packet_get_data(packet),
+                                    packet_get_data_length(packet));
+                        }
+
+                        /* Relese the rest of the packet fragments */
+                        tmp_packet = pq_next(next_packet);
+                        while (tmp_packet) {
+                                next_packet = pq_detach(tmp_packet);
+                                pq_release_remote(udp_globals.net_phone,
+                                    packet_get_id(tmp_packet));
+                                tmp_packet = next_packet;
+                        }
+
+                        /* Exit the loop */
+                        break;
+                }
+                total_length -= length;
+
+                /* Add partial checksum if set */
+                if (header->checksum) {
+                        checksum = compute_checksum(checksum,
+                            packet_get_data(packet),
+                            packet_get_data_length(packet));
+                }
+
+        } while ((next_packet = pq_next(next_packet)) && (total_length > 0));
+
+        /* Verify checksum */
+        if (header->checksum) {
+                if (flip_checksum(compact_checksum(checksum)) !=
+                    IP_CHECKSUM_ZERO) {
+                        if (tl_prepare_icmp_packet(udp_globals.net_phone,
+                            udp_globals.icmp_phone, packet, error) == EOK) {
+                                /* Checksum error ICMP */
+                                icmp_parameter_problem_msg(
+                                    udp_globals.icmp_phone, ICMP_PARAM_POINTER,
+                                    ((size_t) ((void *) &header->checksum)) -
+                                    ((size_t) ((void *) header)), packet);
+                        }
+                        return EINVAL;
+                }
+        }
+
+        /* Queue the received packet */
+        rc = dyn_fifo_push(&socket->received, packet_get_id(packet),
+            SOCKET_MAX_RECEIVED_SIZE);
+        if (rc != EOK)
+                return udp_release_and_return(packet, rc);
+                
+        rc = tl_get_ip_packet_dimension(udp_globals.ip_phone,
+            &udp_globals.dimensions, device_id, &packet_dimension);
+        if (rc != EOK)
+                return udp_release_and_return(packet, rc);
+
+        /* Notify the destination socket */
+        fibril_rwlock_write_unlock(&udp_globals.lock);
+        async_msg_5(socket->phone, NET_SOCKET_RECEIVED,
+            (sysarg_t) socket->socket_id, packet_dimension->content, 0, 0,
+            (sysarg_t) fragments);
+
+        return EOK;
+}
 
 /** Processes the received UDP packet queue.
- *  Notifies the destination socket application.
- *  Releases the packet on error or sends an ICMP error notification..
- *  @param[in] device_id The receiving device identifier.
- *  @param[in,out] packet The received packet queue.
- *  @param[in] error The packet error reporting service. Prefixes the received packet.
- *  @returns EOK on success.
- *  @returns EINVAL if the packet is not valid.
- *  @returns EINVAL if the stored packet address is not the an_addr_t.
- *  @returns EINVAL if the packet does not contain any data.
- *  @returns NO_DATA if the packet content is shorter than the user datagram header.
- *  @returns ENOMEM if there is not enough memory left.
- *  @returns EADDRNOTAVAIL if the destination socket does not exist.
- *  @returns Other error codes as defined for the ip_client_process_packet() function.
- */
-int udp_process_packet(device_id_t device_id, packet_t packet, services_t error);
-
-/** Releases the packet and returns the result.
- *  @param[in] packet The packet queue to be released.
- *  @param[in] result The result to be returned.
- *  @return The result parameter.
- */
-int udp_release_and_return(packet_t packet, int result);
-
-/** @name Socket messages processing functions
- */
-/*@{*/
-
-/** Processes the socket client messages.
- *  Runs until the client module disconnects.
- *  @param[in] callid The message identifier.
- *  @param[in] call The message parameters.
- *  @returns EOK on success.
- *  @see socket.h
- */
-int udp_process_client_messages(ipc_callid_t callid, ipc_call_t call);
-
-/** Sends data from the socket to the remote address.
- *  Binds the socket to a free port if not already connected/bound.
- *  Handles the NET_SOCKET_SENDTO message.
- *  Supports AF_INET and AF_INET6 address families.
- *  @param[in,out] local_sockets The application local sockets.
- *  @param[in] socket_id Socket identifier.
- *  @param[in] addr The destination address.
- *  @param[in] addrlen The address length.
- *  @param[in] fragments The number of data fragments.
- *  @param[out] data_fragment_size The data fragment size in bytes.
- *  @param[in] flags Various send flags.
- *  @returns EOK on success.
- *  @returns EAFNOTSUPPORT if the address family is not supported.
- *  @returns ENOTSOCK if the socket is not found.
- *  @returns EINVAL if the address is invalid.
- *  @returns ENOTCONN if the sending socket is not and cannot be bound.
- *  @returns ENOMEM if there is not enough memory left.
- *  @returns Other error codes as defined for the socket_read_packet_data() function.
- *  @returns Other error codes as defined for the ip_client_prepare_packet() function.
- *  @returns Other error codes as defined for the ip_send_msg() function.
- */
-int udp_sendto_message(socket_cores_ref local_sockets, int socket_id, const struct sockaddr * addr, socklen_t addrlen, int fragments, size_t * data_fragment_size, int flags);
-
-/** Receives data to the socket.
- *  Handles the NET_SOCKET_RECVFROM message.
- *  Replies the source address as well.
- *  @param[in] local_sockets The application local sockets.
- *  @param[in] socket_id Socket identifier.
- *  @param[in] flags Various receive flags.
- *  @param[out] addrlen The source address length.
- *  @returns The number of bytes received.
- *  @returns ENOTSOCK if the socket is not found.
- *  @returns NO_DATA if there are no received packets or data.
- *  @returns ENOMEM if there is not enough memory left.
- *  @returns EINVAL if the received address is not an IP address.
- *  @returns Other error codes as defined for the packet_translate() function.
- *  @returns Other error codes as defined for the data_reply() function.
- */
-int udp_recvfrom_message(socket_cores_ref local_sockets, int socket_id, int flags, size_t * addrlen);
-
-/*@}*/
-
-/** UDP global data.
- */
-udp_globals_t   udp_globals;
-
-int udp_initialize(async_client_conn_t client_connection){
-        ERROR_DECLARE;
-
-        measured_string_t names[] = {{str_dup("UDP_CHECKSUM_COMPUTING"), 22}, {str_dup("UDP_AUTOBINDING"), 15}};
-        measured_string_ref configuration;
+ *
+ * Is used as an entry point from the underlying IP module.
+ * Locks the global lock and calls udp_process_packet() function.
+ *
+ * @param[in] device_id The receiving device identifier.
+ * @param[in,out] packet The received packet queue.
+ * @param receiver      The target service. Ignored parameter.
+ * @param[in] error     The packet error reporting service. Prefixes the
+ *                      received packet.
+ * @return              EOK on success.
+ * @return              Other error codes as defined for the
+ *                      udp_process_packet() function.
+ */
+static int udp_received_msg(device_id_t device_id, packet_t *packet,
+    services_t receiver, services_t error)
+{
+        int result;
+
+        fibril_rwlock_write_lock(&udp_globals.lock);
+        result = udp_process_packet(device_id, packet, error);
+        if (result != EOK)
+                fibril_rwlock_write_unlock(&udp_globals.lock);
+
+        return result;
+}
+
+/** Process IPC messages from the IP module
+ *
+ * @param[in]     iid   Message identifier.
+ * @param[in,out] icall Message parameters.
+ *
+ */
+static void udp_receiver(ipc_callid_t iid, ipc_call_t *icall)
+{
+        packet_t *packet;
+        int rc;
+        
+        while (true) {
+                switch (IPC_GET_IMETHOD(*icall)) {
+                case NET_TL_RECEIVED:
+                        rc = packet_translate_remote(udp_globals.net_phone, &packet,
+                            IPC_GET_PACKET(*icall));
+                        if (rc == EOK)
+                                rc = udp_received_msg(IPC_GET_DEVICE(*icall), packet,
+                                    SERVICE_UDP, IPC_GET_ERROR(*icall));
+                        
+                        async_answer_0(iid, (sysarg_t) rc);
+                        break;
+                default:
+                        async_answer_0(iid, (sysarg_t) ENOTSUP);
+                }
+                
+                iid = async_get_call(icall);
+        }
+}
+
+/** Initialize the UDP module.
+ *
+ * @param[in] net_phone Network module phone.
+ *
+ * @return EOK on success.
+ * @return ENOMEM if there is not enough memory left.
+ *
+ */
+int tl_initialize(int net_phone)
+{
+        measured_string_t names[] = {
+                {
+                        (uint8_t *) "UDP_CHECKSUM_COMPUTING",
+                        22
+                },
+                {
+                        (uint8_t *) "UDP_AUTOBINDING",
+                        15
+                }
+        };
+        measured_string_t *configuration;
         size_t count = sizeof(names) / sizeof(measured_string_t);
-        char * data;
-
+        uint8_t *data;
+        
         fibril_rwlock_initialize(&udp_globals.lock);
         fibril_rwlock_write_lock(&udp_globals.lock);
-        udp_globals.icmp_phone = icmp_connect_module(SERVICE_ICMP, ICMP_CONNECT_TIMEOUT);
-        udp_globals.ip_phone = ip_bind_service(SERVICE_IP, IPPROTO_UDP, SERVICE_UDP, client_connection, udp_received_msg);
-        if(udp_globals.ip_phone < 0){
+        
+        udp_globals.net_phone = net_phone;
+        
+        udp_globals.icmp_phone = icmp_connect_module(ICMP_CONNECT_TIMEOUT);
+        
+        udp_globals.ip_phone = ip_bind_service(SERVICE_IP, IPPROTO_UDP,
+            SERVICE_UDP, udp_receiver);
+        if (udp_globals.ip_phone < 0) {
+                fibril_rwlock_write_unlock(&udp_globals.lock);
                 return udp_globals.ip_phone;
         }
-        // read default packet dimensions
-        ERROR_PROPAGATE(ip_packet_size_req(udp_globals.ip_phone, -1, &udp_globals.packet_dimension));
-        ERROR_PROPAGATE(socket_ports_initialize(&udp_globals.sockets));
-        if(ERROR_OCCURRED(packet_dimensions_initialize(&udp_globals.dimensions))){
-                socket_ports_destroy(&udp_globals.sockets);
-                return ERROR_CODE;
-        }
+        
+        /* Read default packet dimensions */
+        int rc = ip_packet_size_req(udp_globals.ip_phone, -1,
+            &udp_globals.packet_dimension);
+        if (rc != EOK) {
+                fibril_rwlock_write_unlock(&udp_globals.lock);
+                return rc;
+        }
+        
+        rc = socket_ports_initialize(&udp_globals.sockets);
+        if (rc != EOK) {
+                fibril_rwlock_write_unlock(&udp_globals.lock);
+                return rc;
+        }
+        
+        rc = packet_dimensions_initialize(&udp_globals.dimensions);
+        if (rc != EOK) {
+                socket_ports_destroy(&udp_globals.sockets, free);
+                fibril_rwlock_write_unlock(&udp_globals.lock);
+                return rc;
+        }
+        
         udp_globals.packet_dimension.prefix += sizeof(udp_header_t);
         udp_globals.packet_dimension.content -= sizeof(udp_header_t);
         udp_globals.last_used_port = UDP_FREE_PORTS_START - 1;
-        // get configuration
+
         udp_globals.checksum_computing = NET_DEFAULT_UDP_CHECKSUM_COMPUTING;
         udp_globals.autobinding = NET_DEFAULT_UDP_AUTOBINDING;
+
+        /* Get configuration */
         configuration = &names[0];
-        ERROR_PROPAGATE(net_get_conf_req(udp_globals.net_phone, &configuration, count, &data));
-        if(configuration){
-                if(configuration[0].value){
-                        udp_globals.checksum_computing = (configuration[0].value[0] == 'y');
-                }
-                if(configuration[1].value){
-                        udp_globals.autobinding = (configuration[1].value[0] == 'y');
-                }
+        rc = net_get_conf_req(udp_globals.net_phone, &configuration, count,
+            &data);
+        if (rc != EOK) {
+                socket_ports_destroy(&udp_globals.sockets, free);
+                fibril_rwlock_write_unlock(&udp_globals.lock);
+                return rc;
+        }
+        
+        if (configuration) {
+                if (configuration[0].value)
+                        udp_globals.checksum_computing =
+                            (configuration[0].value[0] == 'y');
+                
+                if (configuration[1].value)
+                        udp_globals.autobinding =
+                            (configuration[1].value[0] == 'y');
+
                 net_free_settings(configuration, data);
         }
+
         fibril_rwlock_write_unlock(&udp_globals.lock);
         return EOK;
 }
 
-int udp_received_msg(device_id_t device_id, packet_t packet, services_t receiver, services_t error){
-        int result;
-
-        fibril_rwlock_write_lock(&udp_globals.lock);
-        result = udp_process_packet(device_id, packet, error);
-        if(result != EOK){
-                fibril_rwlock_write_unlock(&udp_globals.lock);
-        }
-
-        return result;
-}
-
-int udp_process_packet(device_id_t device_id, packet_t packet, services_t error){
-        ERROR_DECLARE;
-
-        size_t length;
-        size_t offset;
-        int result;
-        udp_header_ref header;
-        socket_core_ref socket;
-        packet_t next_packet;
-        size_t total_length;
-        uint32_t checksum;
-        int fragments;
-        packet_t tmp_packet;
-        icmp_type_t type;
-        icmp_code_t code;
-        void *ip_header;
-        struct sockaddr * src;
-        struct sockaddr * dest;
-        packet_dimension_ref packet_dimension;
-
-        if(error){
-                switch(error){
-                        case SERVICE_ICMP:
-                                // ignore error
-                                // length = icmp_client_header_length(packet);
-                                // process error
-                                result = icmp_client_process_packet(packet, &type, &code, NULL, NULL);
-                                if(result < 0){
-                                        return udp_release_and_return(packet, result);
-                                }
-                                length = (size_t) result;
-                                if(ERROR_OCCURRED(packet_trim(packet, length, 0))){
-                                        return udp_release_and_return(packet, ERROR_CODE);
-                                }
-                                break;
-                        default:
-                                return udp_release_and_return(packet, ENOTSUP);
-                }
-        }
-        // TODO process received ipopts?
-        result = ip_client_process_packet(packet, NULL, NULL, NULL, NULL, NULL);
-        if(result < 0){
-                return udp_release_and_return(packet, result);
-        }
-        offset = (size_t) result;
-
-        length = packet_get_data_length(packet);
-        if(length <= 0){
-                return udp_release_and_return(packet, EINVAL);
-        }
-        if(length < UDP_HEADER_SIZE + offset){
-                return udp_release_and_return(packet, NO_DATA);
-        }
-
-        // trim all but UDP header
-        if(ERROR_OCCURRED(packet_trim(packet, offset, 0))){
-                return udp_release_and_return(packet, ERROR_CODE);
-        }
-
-        // get udp header
-        header = (udp_header_ref) packet_get_data(packet);
-        if(! header){
-                return udp_release_and_return(packet, NO_DATA);
-        }
-        // find the destination socket
-        socket = socket_port_find(&udp_globals.sockets, ntohs(header->destination_port), SOCKET_MAP_KEY_LISTENING, 0);
-        if(! socket){
-                if(tl_prepare_icmp_packet(udp_globals.net_phone, udp_globals.icmp_phone, packet, error) == EOK){
-                        icmp_destination_unreachable_msg(udp_globals.icmp_phone, ICMP_PORT_UNREACH, 0, packet);
-                }
-                return EADDRNOTAVAIL;
-        }
-
-        // count the received packet fragments
-        next_packet = packet;
-        fragments = 0;
-        total_length = ntohs(header->total_length);
-        // compute header checksum if set
-        if(header->checksum && (! error)){
-                result = packet_get_addr(packet, (uint8_t **) &src, (uint8_t **) &dest);
-                if(result <= 0){
-                        return udp_release_and_return(packet, result);
-                }
-                if(ERROR_OCCURRED(ip_client_get_pseudo_header(IPPROTO_UDP, src, result, dest, result, total_length, &ip_header, &length))){
-                        return udp_release_and_return(packet, ERROR_CODE);
-                }else{
-                        checksum = compute_checksum(0, ip_header, length);
-                        // the udp header checksum will be added with the first fragment later
-                        free(ip_header);
-                }
-        }else{
-                header->checksum = 0;
-                checksum = 0;
-        }
-
-        do{
-                ++ fragments;
-                length = packet_get_data_length(next_packet);
-                if(length <= 0){
-                        return udp_release_and_return(packet, NO_DATA);
-                }
-                if(total_length < length){
-                        if(ERROR_OCCURRED(packet_trim(next_packet, 0, length - total_length))){
-                                return udp_release_and_return(packet, ERROR_CODE);
-                        }
-                        // add partial checksum if set
-                        if(header->checksum){
-                                checksum = compute_checksum(checksum, packet_get_data(packet), packet_get_data_length(packet));
-                        }
-                        // relese the rest of the packet fragments
-                        tmp_packet = pq_next(next_packet);
-                        while(tmp_packet){
-                                next_packet = pq_detach(tmp_packet);
-                                pq_release_remote(udp_globals.net_phone, packet_get_id(tmp_packet));
-                                tmp_packet = next_packet;
-                        }
-                        // exit the loop
-                        break;
-                }
-                total_length -= length;
-                // add partial checksum if set
-                if(header->checksum){
-                        checksum = compute_checksum(checksum, packet_get_data(packet), packet_get_data_length(packet));
-                }
-        }while((next_packet = pq_next(next_packet)) && (total_length > 0));
-
-        // check checksum
-        if(header->checksum){
-                if(flip_checksum(compact_checksum(checksum)) != IP_CHECKSUM_ZERO){
-                        if(tl_prepare_icmp_packet(udp_globals.net_phone, udp_globals.icmp_phone, packet, error) == EOK){
-                                // checksum error ICMP
-                                icmp_parameter_problem_msg(udp_globals.icmp_phone, ICMP_PARAM_POINTER, ((size_t) ((void *) &header->checksum)) - ((size_t) ((void *) header)), packet);
-                        }
-                        return EINVAL;
-                }
-        }
-
-        // queue the received packet
-        if(ERROR_OCCURRED(dyn_fifo_push(&socket->received, packet_get_id(packet), SOCKET_MAX_RECEIVED_SIZE))
-            || ERROR_OCCURRED(tl_get_ip_packet_dimension(udp_globals.ip_phone, &udp_globals.dimensions, device_id, &packet_dimension))){
-                return udp_release_and_return(packet, ERROR_CODE);
-        }
-
-        // notify the destination socket
-        fibril_rwlock_write_unlock(&udp_globals.lock);
-        async_msg_5(socket->phone, NET_SOCKET_RECEIVED, (ipcarg_t) socket->socket_id, packet_dimension->content, 0, 0, (ipcarg_t) fragments);
-        return EOK;
-}
-
-int udp_message_standalone(ipc_callid_t callid, ipc_call_t * call, ipc_call_t * answer, int * answer_count){
-        ERROR_DECLARE;
-
-        packet_t packet;
-
-        *answer_count = 0;
-        switch(IPC_GET_METHOD(*call)){
-                case NET_TL_RECEIVED:
-                        if(! ERROR_OCCURRED(packet_translate_remote(udp_globals.net_phone, &packet, IPC_GET_PACKET(call)))){
-                                ERROR_CODE = udp_received_msg(IPC_GET_DEVICE(call), packet, SERVICE_UDP, IPC_GET_ERROR(call));
-                        }
-                        return ERROR_CODE;
-                case IPC_M_CONNECT_TO_ME:
-                        return udp_process_client_messages(callid, * call);
-        }
-        return ENOTSUP;
-}
-
-int udp_process_client_messages(ipc_callid_t callid, ipc_call_t call){
-        int res;
-        bool keep_on_going = true;
-        socket_cores_t local_sockets;
-        int app_phone = IPC_GET_PHONE(&call);
-        struct sockaddr * addr;
-        int socket_id;
-        size_t addrlen;
-        size_t size;
-        ipc_call_t answer;
-        int answer_count;
-        packet_dimension_ref packet_dimension;
-
-        /*
-         * Accept the connection
-         *  - Answer the first IPC_M_CONNECT_TO_ME call.
-         */
-        res = EOK;
-        answer_count = 0;
-
-        // The client connection is only in one fibril and therefore no additional locks are needed.
-
-        socket_cores_initialize(&local_sockets);
-
-        while(keep_on_going){
-
-                // answer the call
-                answer_call(callid, res, &answer, answer_count);
-
-                // refresh data
-                refresh_answer(&answer, &answer_count);
-
-                // get the next call
-                callid = async_get_call(&call);
-
-                // process the call
-                switch(IPC_GET_METHOD(call)){
-                        case IPC_M_PHONE_HUNGUP:
-                                keep_on_going = false;
-                                res = EHANGUP;
-                                break;
-                        case NET_SOCKET:
-                                socket_id = SOCKET_GET_SOCKET_ID(call);
-                                res = socket_create(&local_sockets, app_phone, NULL, &socket_id);
-                                SOCKET_SET_SOCKET_ID(answer, socket_id);
-
-                                if(res == EOK){
-                                        if (tl_get_ip_packet_dimension(udp_globals.ip_phone, &udp_globals.dimensions, DEVICE_INVALID_ID, &packet_dimension) == EOK){
-                                                SOCKET_SET_DATA_FRAGMENT_SIZE(answer, packet_dimension->content);
-                                        }
-//                                      SOCKET_SET_DATA_FRAGMENT_SIZE(answer, MAX_UDP_FRAGMENT_SIZE);
-                                        SOCKET_SET_HEADER_SIZE(answer, UDP_HEADER_SIZE);
-                                        answer_count = 3;
-                                }
-                                break;
-                        case NET_SOCKET_BIND:
-                                res = data_receive((void **) &addr, &addrlen);
-                                if(res == EOK){
-                                        fibril_rwlock_write_lock(&udp_globals.lock);
-                                        res = socket_bind(&local_sockets, &udp_globals.sockets, SOCKET_GET_SOCKET_ID(call), addr, addrlen, UDP_FREE_PORTS_START, UDP_FREE_PORTS_END, udp_globals.last_used_port);
-                                        fibril_rwlock_write_unlock(&udp_globals.lock);
-                                        free(addr);
-                                }
-                                break;
-                        case NET_SOCKET_SENDTO:
-                                res = data_receive((void **) &addr, &addrlen);
-                                if(res == EOK){
-                                        fibril_rwlock_write_lock(&udp_globals.lock);
-                                        res = udp_sendto_message(&local_sockets, SOCKET_GET_SOCKET_ID(call), addr, addrlen, SOCKET_GET_DATA_FRAGMENTS(call), &size, SOCKET_GET_FLAGS(call));
-                                        SOCKET_SET_DATA_FRAGMENT_SIZE(answer, size);
-                                        if(res != EOK){
-                                                fibril_rwlock_write_unlock(&udp_globals.lock);
-                                        }else{
-                                                answer_count = 2;
-                                        }
-                                        free(addr);
-                                }
-                                break;
-                        case NET_SOCKET_RECVFROM:
-                                fibril_rwlock_write_lock(&udp_globals.lock);
-                                res = udp_recvfrom_message(&local_sockets, SOCKET_GET_SOCKET_ID(call), SOCKET_GET_FLAGS(call), &addrlen);
-                                fibril_rwlock_write_unlock(&udp_globals.lock);
-                                if(res > 0){
-                                        SOCKET_SET_READ_DATA_LENGTH(answer, res);
-                                        SOCKET_SET_ADDRESS_LENGTH(answer, addrlen);
-                                        answer_count = 3;
-                                        res = EOK;
-                                }
-                                break;
-                        case NET_SOCKET_CLOSE:
-                                fibril_rwlock_write_lock(&udp_globals.lock);
-                                res = socket_destroy(udp_globals.net_phone, SOCKET_GET_SOCKET_ID(call), &local_sockets, &udp_globals.sockets, NULL);
-                                fibril_rwlock_write_unlock(&udp_globals.lock);
-                                break;
-                        case NET_SOCKET_GETSOCKOPT:
-                        case NET_SOCKET_SETSOCKOPT:
-                        default:
-                                res = ENOTSUP;
-                                break;
-                }
-        }
-
-        // release the application phone
-        ipc_hangup(app_phone);
-
-        // release all local sockets
-        socket_cores_release(udp_globals.net_phone, &local_sockets, &udp_globals.sockets, NULL);
-
-        return res;
-}
-
-int udp_sendto_message(socket_cores_ref local_sockets, int socket_id, const struct sockaddr * addr, socklen_t addrlen, int fragments, size_t * data_fragment_size, int flags){
-        ERROR_DECLARE;
-
-        socket_core_ref socket;
-        packet_t packet;
-        packet_t next_packet;
-        udp_header_ref header;
+/** Sends data from the socket to the remote address.
+ *
+ * Binds the socket to a free port if not already connected/bound.
+ * Handles the NET_SOCKET_SENDTO message.
+ * Supports AF_INET and AF_INET6 address families.
+ *
+ * @param[in,out] local_sockets The application local sockets.
+ * @param[in] socket_id Socket identifier.
+ * @param[in] addr      The destination address.
+ * @param[in] addrlen   The address length.
+ * @param[in] fragments The number of data fragments.
+ * @param[out] data_fragment_size The data fragment size in bytes.
+ * @param[in] flags     Various send flags.
+ * @return              EOK on success.
+ * @return              EAFNOTSUPPORT if the address family is not supported.
+ * @return              ENOTSOCK if the socket is not found.
+ * @return              EINVAL if the address is invalid.
+ * @return              ENOTCONN if the sending socket is not and cannot be
+ *                      bound.
+ * @return              ENOMEM if there is not enough memory left.
+ * @return              Other error codes as defined for the
+ *                      socket_read_packet_data() function.
+ * @return              Other error codes as defined for the
+ *                      ip_client_prepare_packet() function.
+ * @return              Other error codes as defined for the ip_send_msg()
+ *                      function.
+ */
+static int udp_sendto_message(socket_cores_t *local_sockets, int socket_id,
+    const struct sockaddr *addr, socklen_t addrlen, int fragments,
+    size_t *data_fragment_size, int flags)
+{
+        socket_core_t *socket;
+        packet_t *packet;
+        packet_t *next_packet;
+        udp_header_t *header;
         int index;
         size_t total_length;
@@ -539 +498 @@
         size_t headerlen;
         device_id_t device_id;
-        packet_dimension_ref packet_dimension;
-
-        ERROR_PROPAGATE(tl_get_address_port(addr, addrlen, &dest_port));
+        packet_dimension_t *packet_dimension;
+        size_t size;
+        int rc;
+
+        /* In case of error, do not update the data fragment size. */
+        *data_fragment_size = 0;
+        
+        rc = tl_get_address_port(addr, addrlen, &dest_port);
+        if (rc != EOK)
+                return rc;
 
         socket = socket_cores_find(local_sockets, socket_id);
-        if(! socket){
+        if (!socket)
                 return ENOTSOCK;
-        }
-
-        if((socket->port <= 0) && udp_globals.autobinding){
-                // bind the socket to a random free port if not bound
-//              do{
-                        // try to find a free port
-//                      fibril_rwlock_read_unlock(&udp_globals.lock);
-//                      fibril_rwlock_write_lock(&udp_globals.lock);
-                        // might be changed in the meantime
-//                      if(socket->port <= 0){
-                                if(ERROR_OCCURRED(socket_bind_free_port(&udp_globals.sockets, socket, UDP_FREE_PORTS_START, UDP_FREE_PORTS_END, udp_globals.last_used_port))){
-//                                      fibril_rwlock_write_unlock(&udp_globals.lock);
-//                                      fibril_rwlock_read_lock(&udp_globals.lock);
-                                        return ERROR_CODE;
-                                }
-                                // set the next port as the search starting port number
-                                udp_globals.last_used_port = socket->port;
-//                      }
-//                      fibril_rwlock_write_unlock(&udp_globals.lock);
-//                      fibril_rwlock_read_lock(&udp_globals.lock);
-                        // might be changed in the meantime
-//              }while(socket->port <= 0);
-        }
-
-        if(udp_globals.checksum_computing){
-                if(ERROR_OCCURRED(ip_get_route_req(udp_globals.ip_phone, IPPROTO_UDP, addr, addrlen, &device_id, &ip_header, &headerlen))){
-                        return udp_release_and_return(packet, ERROR_CODE);
-                }
-                // get the device packet dimension
-//              ERROR_PROPAGATE(tl_get_ip_packet_dimension(udp_globals.ip_phone, &udp_globals.dimensions, device_id, &packet_dimension));
-        }
-//      }else{
-                // do not ask all the time
-                ERROR_PROPAGATE(ip_packet_size_req(udp_globals.ip_phone, -1, &udp_globals.packet_dimension));
+
+        if ((socket->port <= 0) && udp_globals.autobinding) {
+                /* Bind the socket to a random free port if not bound */
+                rc = socket_bind_free_port(&udp_globals.sockets, socket,
+                    UDP_FREE_PORTS_START, UDP_FREE_PORTS_END,
+                    udp_globals.last_used_port);
+                if (rc != EOK)
+                        return rc;
+                /* Set the next port as the search starting port number */
+                udp_globals.last_used_port = socket->port;
+        }
+
+        if (udp_globals.checksum_computing) {
+                rc = ip_get_route_req(udp_globals.ip_phone, IPPROTO_UDP, addr,
+                    addrlen, &device_id, &ip_header, &headerlen);
+                if (rc != EOK)
+                        return rc;
+                /* Get the device packet dimension */
+//              rc = tl_get_ip_packet_dimension(udp_globals.ip_phone,
+//                  &udp_globals.dimensions, device_id, &packet_dimension);
+//              if (rc != EOK)
+//                      return rc;
+        }
+//      } else {
+                /* Do not ask all the time */
+                rc = ip_packet_size_req(udp_globals.ip_phone, -1,
+                    &udp_globals.packet_dimension);
+                if (rc != EOK)
+                        return rc;
                 packet_dimension = &udp_globals.packet_dimension;
 //      }
 
-        // read the first packet fragment
-        result = tl_socket_read_packet_data(udp_globals.net_phone, &packet, UDP_HEADER_SIZE, packet_dimension, addr, addrlen);
-        if(result < 0){
+        /*
+         * Update the data fragment size based on what the lower layers can
+         * handle without fragmentation, but not more than the maximum allowed
+         * for UDP.
+         */
+        size = MAX_UDP_FRAGMENT_SIZE;
+        if (packet_dimension->content < size)
+            size = packet_dimension->content;
+        *data_fragment_size = size;
+
+        /* Read the first packet fragment */
+        result = tl_socket_read_packet_data(udp_globals.net_phone, &packet,
+            UDP_HEADER_SIZE, packet_dimension, addr, addrlen);
+        if (result < 0)
                 return result;
-        }
+
         total_length = (size_t) result;
-        if(udp_globals.checksum_computing){
-                checksum = compute_checksum(0, packet_get_data(packet), packet_get_data_length(packet));
-        }else{
+        if (udp_globals.checksum_computing)
+                checksum = compute_checksum(0, packet_get_data(packet),
+                    packet_get_data_length(packet));
+        else
                 checksum = 0;
-        }
-        // prefix the udp header
+
+        /* Prefix the UDP header */
         header = PACKET_PREFIX(packet, udp_header_t);
-        if(! header){
+        if (!header)
                 return udp_release_and_return(packet, ENOMEM);
-        }
+
         bzero(header, sizeof(*header));
-        // read the rest of the packet fragments
-        for(index = 1; index < fragments; ++ index){
-                result = tl_socket_read_packet_data(udp_globals.net_phone, &next_packet, 0, packet_dimension, addr, addrlen);
-                if(result < 0){
+
+        /* Read the rest of the packet fragments */
+        for (index = 1; index < fragments; index++) {
+                result = tl_socket_read_packet_data(udp_globals.net_phone,
+                    &next_packet, 0, packet_dimension, addr, addrlen);
+                if (result < 0)
                         return udp_release_and_return(packet, result);
+
+                rc = pq_add(&packet, next_packet, index, 0);
+                if (rc != EOK)
+                        return udp_release_and_return(packet, rc);
+
+                total_length += (size_t) result;
+                if (udp_globals.checksum_computing) {
+                        checksum = compute_checksum(checksum,
+                            packet_get_data(next_packet),
+                            packet_get_data_length(next_packet));
                 }
-                if(ERROR_OCCURRED(pq_add(&packet, next_packet, index, 0))){
-                        return udp_release_and_return(packet, ERROR_CODE);
-                }
-                total_length += (size_t) result;
-                if(udp_globals.checksum_computing){
-                        checksum = compute_checksum(checksum, packet_get_data(next_packet), packet_get_data_length(next_packet));
-                }
-        }
-        // set the udp header
+        }
+
+        /* Set the UDP header */
         header->source_port = htons((socket->port > 0) ? socket->port : 0);
         header->destination_port = htons(dest_port);
         header->total_length = htons(total_length + sizeof(*header));
         header->checksum = 0;
-        if(udp_globals.checksum_computing){
-                // update the pseudo header
-                if(ERROR_OCCURRED(ip_client_set_pseudo_header_data_length(ip_header, headerlen, total_length + UDP_HEADER_SIZE))){
+
+        if (udp_globals.checksum_computing) {
+                /* Update the pseudo header */
+                rc = ip_client_set_pseudo_header_data_length(ip_header,
+                    headerlen, total_length + UDP_HEADER_SIZE);
+                if (rc != EOK) {
                         free(ip_header);
-                        return udp_release_and_return(packet, ERROR_CODE);
+                        return udp_release_and_return(packet, rc);
                 }
-                // finish the checksum computation
+
+                /* Finish the checksum computation */
                 checksum = compute_checksum(checksum, ip_header, headerlen);
-                checksum = compute_checksum(checksum, (uint8_t *) header, sizeof(*header));
-                header->checksum = htons(flip_checksum(compact_checksum(checksum)));
+                checksum = compute_checksum(checksum, (uint8_t *) header,
+                    sizeof(*header));
+                header->checksum =
+                    htons(flip_checksum(compact_checksum(checksum)));
                 free(ip_header);
-        }else{
+        } else {
                 device_id = DEVICE_INVALID_ID;
         }
-        // prepare the first packet fragment
-        if(ERROR_OCCURRED(ip_client_prepare_packet(packet, IPPROTO_UDP, 0, 0, 0, 0))){
-                return udp_release_and_return(packet, ERROR_CODE);
-        }
-        // send the packet
+
+        /* Prepare the first packet fragment */
+        rc = ip_client_prepare_packet(packet, IPPROTO_UDP, 0, 0, 0, 0);
+        if (rc != EOK)
+                return udp_release_and_return(packet, rc);
+
+        /* Release the UDP global lock on success. */
         fibril_rwlock_write_unlock(&udp_globals.lock);
+
+        /* Send the packet */
         ip_send_msg(udp_globals.ip_phone, device_id, packet, SERVICE_UDP, 0);
+
         return EOK;
 }
 
-int udp_recvfrom_message(socket_cores_ref local_sockets, int socket_id, int flags, size_t * addrlen){
-        ERROR_DECLARE;
-
-        socket_core_ref socket;
+/** Receives data to the socket.
+ *
+ * Handles the NET_SOCKET_RECVFROM message.
+ * Replies the source address as well.
+ *
+ * @param[in] local_sockets The application local sockets.
+ * @param[in] socket_id Socket identifier.
+ * @param[in] flags     Various receive flags.
+ * @param[out] addrlen  The source address length.
+ * @return              The number of bytes received.
+ * @return              ENOTSOCK if the socket is not found.
+ * @return              NO_DATA if there are no received packets or data.
+ * @return              ENOMEM if there is not enough memory left.
+ * @return              EINVAL if the received address is not an IP address.
+ * @return              Other error codes as defined for the packet_translate()
+ *                      function.
+ * @return              Other error codes as defined for the data_reply()
+ *                      function.
+ */
+static int udp_recvfrom_message(socket_cores_t *local_sockets, int socket_id,
+    int flags, size_t *addrlen)
+{
+        socket_core_t *socket;
         int packet_id;
-        packet_t packet;
-        udp_header_ref header;
-        struct sockaddr * addr;
+        packet_t *packet;
+        udp_header_t *header;
+        struct sockaddr *addr;
         size_t length;
-        uint8_t * data;
+        uint8_t *data;
         int result;
-
-        // find the socket
+        int rc;
+
+        /* Find the socket */
         socket = socket_cores_find(local_sockets, socket_id);
-        if(! socket){
+        if (!socket)
                 return ENOTSOCK;
-        }
-        // get the next received packet
+
+        /* Get the next received packet */
         packet_id = dyn_fifo_value(&socket->received);
-        if(packet_id < 0){
+        if (packet_id < 0)
                 return NO_DATA;
-        }
-        ERROR_PROPAGATE(packet_translate_remote(udp_globals.net_phone, &packet, packet_id));
-        // get udp header
+        
+        rc = packet_translate_remote(udp_globals.net_phone, &packet, packet_id);
+        if (rc != EOK) {
+                (void) dyn_fifo_pop(&socket->received);
+                return rc;
+        }
+
+        /* Get UDP header */
         data = packet_get_data(packet);
-        if(! data){
-                pq_release_remote(udp_globals.net_phone, packet_id);
-                return NO_DATA;
-        }
-        header = (udp_header_ref) data;
-
-        // set the source address port
+        if (!data) {
+                (void) dyn_fifo_pop(&socket->received);
+                return udp_release_and_return(packet, NO_DATA);
+        }
+        header = (udp_header_t *) data;
+
+        /* Set the source address port */
         result = packet_get_addr(packet, (uint8_t **) &addr, NULL);
-        if(ERROR_OCCURRED(tl_set_address_port(addr, result, ntohs(header->source_port)))){
-                pq_release_remote(udp_globals.net_phone, packet_id);
-                return ERROR_CODE;
+        rc = tl_set_address_port(addr, result, ntohs(header->source_port));
+        if (rc != EOK) {
+                (void) dyn_fifo_pop(&socket->received);
+                return udp_release_and_return(packet, rc);
         }
         *addrlen = (size_t) result;
-        // send the source address
-        ERROR_PROPAGATE(data_reply(addr, * addrlen));
-
-        // trim the header
-        ERROR_PROPAGATE(packet_trim(packet, UDP_HEADER_SIZE, 0));
-
-        // reply the packets
-        ERROR_PROPAGATE(socket_reply_packets(packet, &length));
-
-        // release the packet
-        dyn_fifo_pop(&socket->received);
-        pq_release_remote(udp_globals.net_phone, packet_get_id(packet));
-        // return the total length
-        return (int) length;
-}
-
-int udp_release_and_return(packet_t packet, int result){
-        pq_release_remote(udp_globals.net_phone, packet_get_id(packet));
-        return result;
-}
-
-/** Default thread for new connections.
- *
- *  @param[in] iid The initial message identifier.
- *  @param[in] icall The initial message call structure.
- *
- */
-static void tl_client_connection(ipc_callid_t iid, ipc_call_t * icall)
-{
+
+        /* Send the source address */
+        rc = data_reply(addr, *addrlen);
+        switch (rc) {
+        case EOK:
+                break;
+        case EOVERFLOW:
+                return rc;
+        default:
+                (void) dyn_fifo_pop(&socket->received);
+                return udp_release_and_return(packet, rc);
+        }
+
+        /* Trim the header */
+        rc = packet_trim(packet, UDP_HEADER_SIZE, 0);
+        if (rc != EOK) {
+                (void) dyn_fifo_pop(&socket->received);
+                return udp_release_and_return(packet, rc);
+        }
+
+        /* Reply the packets */
+        rc = socket_reply_packets(packet, &length);
+        switch (rc) {
+        case EOK:
+                break;
+        case EOVERFLOW:
+                return rc;
+        default:
+                (void) dyn_fifo_pop(&socket->received);
+                return udp_release_and_return(packet, rc);
+        }
+
+        (void) dyn_fifo_pop(&socket->received);
+
+        /* Release the packet and return the total length */
+        return udp_release_and_return(packet, (int) length);
+}
+
+/** Processes the socket client messages.
+ *
+ * Runs until the client module disconnects.
+ *
+ * @param[in] callid    The message identifier.
+ * @param[in] call      The message parameters.
+ * @return              EOK on success.
+ *
+ * @see socket.h
+ */
+static int udp_process_client_messages(ipc_callid_t callid, ipc_call_t call)
+{
+        int res;
+        bool keep_on_going = true;
+        socket_cores_t local_sockets;
+        int app_phone = IPC_GET_PHONE(call);
+        struct sockaddr *addr;
+        int socket_id;
+        size_t addrlen;
+        size_t size;
+        ipc_call_t answer;
+        size_t answer_count;
+        packet_dimension_t *packet_dimension;
+
         /*
          * Accept the connection
-         *  - Answer the first IPC_M_CONNECT_ME_TO call.
+         *  - Answer the first IPC_M_CONNECT_TO_ME call.
          */
-        ipc_answer_0(iid, EOK);
-        
-        while(true) {
-                ipc_call_t answer;
-                int answer_count;
-                
-                /* Clear the answer structure */
+        res = EOK;
+        answer_count = 0;
+
+        /*
+         * The client connection is only in one fibril and therefore no
+         * additional locks are needed.
+         */
+
+        socket_cores_initialize(&local_sockets);
+
+        while (keep_on_going) {
+
+                /* Answer the call */
+                answer_call(callid, res, &answer, answer_count);
+
+                /* Refresh data */
                 refresh_answer(&answer, &answer_count);
-                
-                /* Fetch the next message */
-                ipc_call_t call;
-                ipc_callid_t callid = async_get_call(&call);
-                
-                /* Process the message */
-                int res = tl_module_message_standalone(callid, &call, &answer,
-                    &answer_count);
-                
-                /* End if said to either by the message or the processing result */
-                if ((IPC_GET_METHOD(call) == IPC_M_PHONE_HUNGUP) || (res == EHANGUP))
-                        return;
-                
-                /* Answer the message */
-                answer_call(callid, res, &answer, answer_count);
-        }
-}
-
-/** Starts the module.
- *
- *  @param argc The count of the command line arguments. Ignored parameter.
- *  @param argv The command line parameters. Ignored parameter.
- *
- *  @returns EOK on success.
- *  @returns Other error codes as defined for each specific module start function.
- *
- */
+
+                /* Get the next call */
+                callid = async_get_call(&call);
+
+                /* Process the call */
+                switch (IPC_GET_IMETHOD(call)) {
+                case IPC_M_PHONE_HUNGUP:
+                        keep_on_going = false;
+                        res = EHANGUP;
+                        break;
+
+                case NET_SOCKET:
+                        socket_id = SOCKET_GET_SOCKET_ID(call);
+                        res = socket_create(&local_sockets, app_phone, NULL,
+                            &socket_id);
+                        SOCKET_SET_SOCKET_ID(answer, socket_id);
+
+                        if (res != EOK)
+                                break;
+                        
+                        size = MAX_UDP_FRAGMENT_SIZE;
+                        if (tl_get_ip_packet_dimension(udp_globals.ip_phone,
+                            &udp_globals.dimensions, DEVICE_INVALID_ID,
+                            &packet_dimension) == EOK) {
+                                if (packet_dimension->content < size)
+                                        size = packet_dimension->content;
+                        }
+                        SOCKET_SET_DATA_FRAGMENT_SIZE(answer, size);
+                        SOCKET_SET_HEADER_SIZE(answer, UDP_HEADER_SIZE);
+                        answer_count = 3;
+                        break;
+
+                case NET_SOCKET_BIND:
+                        res = async_data_write_accept((void **) &addr, false,
+                            0, 0, 0, &addrlen);
+                        if (res != EOK)
+                                break;
+                        fibril_rwlock_write_lock(&udp_globals.lock);
+                        res = socket_bind(&local_sockets, &udp_globals.sockets,
+                            SOCKET_GET_SOCKET_ID(call), addr, addrlen,
+                            UDP_FREE_PORTS_START, UDP_FREE_PORTS_END,
+                            udp_globals.last_used_port);
+                        fibril_rwlock_write_unlock(&udp_globals.lock);
+                        free(addr);
+                        break;
+
+                case NET_SOCKET_SENDTO:
+                        res = async_data_write_accept((void **) &addr, false,
+                            0, 0, 0, &addrlen);
+                        if (res != EOK)
+                                break;
+
+                        fibril_rwlock_write_lock(&udp_globals.lock);
+                        res = udp_sendto_message(&local_sockets,
+                            SOCKET_GET_SOCKET_ID(call), addr, addrlen,
+                            SOCKET_GET_DATA_FRAGMENTS(call), &size,
+                            SOCKET_GET_FLAGS(call));
+                        SOCKET_SET_DATA_FRAGMENT_SIZE(answer, size);
+
+                        if (res != EOK)
+                                fibril_rwlock_write_unlock(&udp_globals.lock);
+                        else
+                                answer_count = 2;
+                        
+                        free(addr);
+                        break;
+
+                case NET_SOCKET_RECVFROM:
+                        fibril_rwlock_write_lock(&udp_globals.lock);
+                        res = udp_recvfrom_message(&local_sockets,
+                             SOCKET_GET_SOCKET_ID(call), SOCKET_GET_FLAGS(call),
+                             &addrlen);
+                        fibril_rwlock_write_unlock(&udp_globals.lock);
+
+                        if (res <= 0)
+                                break;
+
+                        SOCKET_SET_READ_DATA_LENGTH(answer, res);
+                        SOCKET_SET_ADDRESS_LENGTH(answer, addrlen);
+                        answer_count = 3;
+                        res = EOK;
+                        break;
+                        
+                case NET_SOCKET_CLOSE:
+                        fibril_rwlock_write_lock(&udp_globals.lock);
+                        res = socket_destroy(udp_globals.net_phone,
+                            SOCKET_GET_SOCKET_ID(call), &local_sockets,
+                            &udp_globals.sockets, NULL);
+                        fibril_rwlock_write_unlock(&udp_globals.lock);
+                        break;
+
+                case NET_SOCKET_GETSOCKOPT:
+                case NET_SOCKET_SETSOCKOPT:
+                default:
+                        res = ENOTSUP;
+                        break;
+                }
+        }
+
+        /* Release the application phone */
+        async_hangup(app_phone);
+
+        /* Release all local sockets */
+        socket_cores_release(udp_globals.net_phone, &local_sockets,
+            &udp_globals.sockets, NULL);
+
+        return res;
+}
+
+/** Per-connection initialization
+ *
+ */
+void tl_connection(void)
+{
+}
+
+/** Processes the UDP message.
+ *
+ * @param[in] callid    The message identifier.
+ * @param[in] call      The message parameters.
+ * @param[out] answer   The message answer parameters.
+ * @param[out] answer_count The last parameter for the actual answer in the
+ *                      answer parameter.
+ * @return              EOK on success.
+ * @return              ENOTSUP if the message is not known.
+ *
+ * @see udp_interface.h
+ * @see IS_NET_UDP_MESSAGE()
+ */
+int tl_message(ipc_callid_t callid, ipc_call_t *call,
+    ipc_call_t *answer, size_t *answer_count)
+{
+        *answer_count = 0;
+
+        switch (IPC_GET_IMETHOD(*call)) {
+        case IPC_M_CONNECT_TO_ME:
+                return udp_process_client_messages(callid, *call);
+        }
+
+        return ENOTSUP;
+}
+
 int main(int argc, char *argv[])
 {
-        ERROR_DECLARE;
-        
         /* Start the module */
-        if (ERROR_OCCURRED(tl_module_start_standalone(tl_client_connection)))
-                return ERROR_CODE;
-        
-        return EOK;
+        return tl_module_start(SERVICE_UDP);
 }