source: mainline/uspace/srv/net/il/ip/ip.c@ 02d9fec

/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup ip
 *  @{
 */

/** @file
 *  IP module implementation.
 *  @see arp.h
 */

#include <async.h>
#include <errno.h>
#include <fibril_synch.h>
#include <stdio.h>
#include <string.h>

#include <ipc/ipc.h>
#include <ipc/services.h>

#include <sys/types.h>

#include "../../err.h"
#include "../../messages.h"
#include "../../modules.h"

#include "../../include/arp_interface.h"
#include "../../include/byteorder.h"
#include "../../include/checksum.h"
#include "../../include/device.h"
#include "../../include/icmp_client.h"
#include "../../include/icmp_codes.h"
#include "../../include/icmp_interface.h"
#include "../../include/il_interface.h"
#include "../../include/in.h"
#include "../../include/in6.h"
#include "../../include/inet.h"
#include "../../include/ip_client.h"
#include "../../include/ip_interface.h"
#include "../../include/net_interface.h"
#include "../../include/nil_interface.h"
#include "../../include/tl_interface.h"
#include "../../include/socket_codes.h"
#include "../../include/socket_errno.h"
#include "../../structures/measured_strings.h"
#include "../../structures/module_map.h"
#include "../../structures/packet/packet_client.h"

#include "../../nil/nil_messages.h"

#include "../il_messages.h"

#include "ip.h"
#include "ip_header.h"
#include "ip_messages.h"
#include "ip_module.h"

/** IP version 4.
 */
#define IPV4                            4

/** Default network interface IP version.
 */
#define NET_DEFAULT_IPV         IPV4

/** Default network interface IP routing.
 */
#define NET_DEFAULT_IP_ROUTING  false

/** Minimum IP packet content.
 */
#define IP_MIN_CONTENT  576

/** ARP module name.
 */
#define ARP_NAME                                "arp"

/** ARP module filename.
 */
#define ARP_FILENAME                    "/srv/arp"

/** IP packet address length.
 */
#define IP_ADDR                                                 sizeof(struct sockaddr_in6)

/** IP packet prefix length.
 */
#define IP_PREFIX                                               sizeof(ip_header_t)

/** IP packet suffix length.
 */
#define IP_SUFFIX                                               0

/** IP packet maximum content length.
 */
#define IP_MAX_CONTENT                                  65535

/** The IP localhost address.
 */
#define IPV4_LOCALHOST_ADDRESS  htonl((127 << 24) + 1)

/** IP global data.
 */
ip_globals_t    ip_globals;

DEVICE_MAP_IMPLEMENT(ip_netifs, ip_netif_t)

INT_MAP_IMPLEMENT(ip_protos, ip_proto_t)

GENERIC_FIELD_IMPLEMENT(ip_routes, ip_route_t)

/** Updates the device content length according to the new MTU value.
 *  @param[in] device_id The device identifier.
 *  @param[in] mtu The new mtu value.
 *  @returns EOK on success.
 *  @returns ENOENT if device is not found.
 */
int ip_mtu_changed_message(device_id_t device_id, size_t mtu);

/** Updates the device state.
 *  @param[in] device_id The device identifier.
 *  @param[in] state The new state value.
 *  @returns EOK on success.
 *  @returns ENOENT if device is not found.
 */
int ip_device_state_message(device_id_t device_id, device_state_t state);

/** Returns the device packet dimensions for sending.
 *  @param[in] phone The service module phone.
 *  @param[in] message The service specific message.
 *  @param[in] device_id The device identifier.
 *  @param[out] addr_len The minimum reserved address length.
 *  @param[out] prefix The minimum reserved prefix size.
 *  @param[out] content The maximum content size.
 *  @param[out] suffix The minimum reserved suffix size.
 *  @returns EOK on success.
 */
int ip_packet_size_message(device_id_t device_id, size_t * addr_len, size_t * prefix, size_t * content, size_t * suffix);

/** Registers the transport layer protocol.
 *  The traffic of this protocol will be supplied using either the receive function or IPC message.
 *  @param[in] protocol The transport layer module protocol.
 *  @param[in] service The transport layer module service.
 *  @param[in] phone The transport layer module phone.
 *  @param[in] tl_received_msg The receiving function.
 *  @returns EOK on success.
 *  @returns EINVAL if the protocol parameter and/or the service parameter is zero (0).
 *  @returns EINVAL if the phone parameter is not a positive number and the tl_receive_msg is NULL.
 *  @returns ENOMEM if there is not enough memory left.
 */
int ip_register(int protocol, services_t service, int phone, tl_received_msg_t tl_received_msg);

/** Initializes a new network interface specific data.
 *  Connects to the network interface layer module, reads the netif configuration, starts an ARP module if needed and sets the netif routing table.
 *  The device identifier and the nil service has to be set.
 *  @param[in,out] ip_netif Network interface specific data.
 *  @returns EOK on success.
 *  @returns ENOTSUP if DHCP is configured.
 *  @returns ENOTSUP if IPv6 is configured.
 *  @returns EINVAL if any of the addresses is invalid.
 *  @returns EINVAL if the used ARP module is not known.
 *  @returns ENOMEM if there is not enough memory left.
 *  @returns Other error codes as defined for the net_get_device_conf_req() function.
 *  @returns Other error codes as defined for the bind_service() function.
 *  @returns Other error codes as defined for the specific arp_device_req() function.
 *  @returns Other error codes as defined for the nil_packet_size_req() function.
 */
int ip_netif_initialize(ip_netif_ref ip_netif);

/** Sends the packet or the packet queue via the specified route.
 *  The ICMP_HOST_UNREACH error notification may be sent if route hardware destination address is found.
 *  @param[in,out] packet The packet to be sent.
 *  @param[in] netif The target network interface.
 *  @param[in] route The target route.
 *  @param[in] src The source address.
 *  @param[in] dest The destination address.
 *  @param[in] error The error module service.
 *  @returns EOK on success.
 *  @returns Other error codes as defined for the arp_translate_req() function.
 *  @returns Other error codes as defined for the ip_prepare_packet() function.
 */
int ip_send_route(packet_t packet, ip_netif_ref netif, ip_route_ref route, in_addr_t * src, in_addr_t dest, services_t error);

/** Prepares the outgoing packet or the packet queue.
 *  The packet queue is a fragmented packet
 *  Updates the first packet's IP header.
 *  Prefixes the additional packets with fragment headers.
 *  @param[in] source The source address.
 *  @param[in] dest The destination address.
 *  @param[in,out] packet The packet to be sent.
 *  @param[in] destination The destination hardware address.
 *  @returns EOK on success.
 *  @returns EINVAL if the packet is too small to contain the IP header.
 *  @returns EINVAL if the packet is too long than the IP allows.
 *  @returns ENOMEM if there is not enough memory left.
 *  @returns Other error codes as defined for the packet_set_addr() function.
 */
int ip_prepare_packet(in_addr_t * source, in_addr_t dest, packet_t packet, measured_string_ref destination);

/** Checks the packet queue lengths and fragments the packets if needed.
 *  The ICMP_FRAG_NEEDED error notification may be sent if the packet needs to be fragmented and the fragmentation is not allowed.
 *  @param[in,out] packet The packet or the packet queue to be checked.
 *  @param[in] prefix The minimum prefix size.
 *  @param[in] content The maximum content size.
 *  @param[in] suffix The minimum suffix size.
 *  @param[in] addr_len The minimum address length.
 *  @param[in] error The error module service.
 *  @returns The packet or the packet queue of the allowed length.
 *  @returns NULL if there are no packets left.
 */
packet_t ip_split_packet(packet_t packet, size_t prefix, size_t content, size_t suffix, socklen_t addr_len, services_t error);

/** Checks the packet length and fragments it if needed.
 *  The new fragments are queued before the original packet.
 *  @param[in,out] packet The packet to be checked.
 *  @param[in] length The maximum packet length.
 *  @param[in] prefix The minimum prefix size.
 *  @param[in] suffix The minimum suffix size.
 *  @param[in] addr_len The minimum address length.
 *  @returns EOK on success.
 *  @returns EINVAL if the packet_get_addr() function fails.
 *  @returns EINVAL if the packet does not contain the IP header.
 *  @returns EPERM if the packet needs to be fragmented and the fragmentation is not allowed.
 *  @returns ENOMEM if there is not enough memory left.
 *  @returns ENOMEM if there is no packet available.
 *  @returns ENOMEM if the packet is too small to contain the IP header.
 *  @returns Other error codes as defined for the packet_trim() function.
 *  @returns Other error codes as defined for the ip_create_middle_header() function.
 *  @returns Other error codes as defined for the ip_fragment_packet_data() function.
 */
int ip_fragment_packet(packet_t packet, size_t length, size_t prefix, size_t suffix, socklen_t addr_len);

/** Fragments the packet from the end.
 *  @param[in] packet The packet to be fragmented.
 *  @param[in,out] new_packet The new packet fragment.
 *  @param[in,out] header The original packet header.
 *  @param[in,out] new_header The new packet fragment header.
 *  @param[in] length The new fragment length.
 *  @param[in] src The source address.
 *  @param[in] dest The destiantion address.
 *  @param[in] addrlen The address length.
 *  @returns EOK on success.
 *  @returns ENOMEM if the target packet is too small.
 *  @returns Other error codes as defined for the packet_set_addr() function.
 *  @returns Other error codes as defined for the pq_insert_after() function.
 */
int ip_fragment_packet_data(packet_t packet, packet_t new_packet, ip_header_ref header, ip_header_ref new_header, size_t length, const struct sockaddr * src, const struct sockaddr * dest, socklen_t addrlen);

/** Prefixes a middle fragment header based on the last fragment header to the packet.
 *  @param[in] packet The packet to be prefixed.
 *  @param[in] last The last header to be copied.
 *  @returns The prefixed middle header.
 *  @returns NULL on error.
 */
ip_header_ref ip_create_middle_header(packet_t packet, ip_header_ref last);

/** Copies the fragment header.
 *  Copies only the header itself and relevant IP options.
 *  @param[out] last The created header.
 *  @param[in] first The original header to be copied.
 */
void ip_create_last_header(ip_header_ref last, ip_header_ref first);

/** Returns the network interface's IP address.
 *  @param[in] netif The network interface.
 *  @returns The IP address.
 *  @returns NULL if no IP address was found.
 */
in_addr_t * ip_netif_address(ip_netif_ref netif);

/** Searches all network interfaces if there is a suitable route.
 *  @param[in] destination The destination address.
 *  @returns The found route.
 *  @returns NULL if no route was found.
 */
ip_route_ref ip_find_route(in_addr_t destination);

/** Searches the network interfaces if there is a suitable route.
 *  @param[in] netif The network interface to be searched for routes. May be NULL.
 *  @param[in] destination The destination address.
 *  @returns The found route.
 *  @returns NULL if no route was found.
 */
ip_route_ref ip_netif_find_route(ip_netif_ref netif, in_addr_t destination);

/** Processes the received IP packet or the packet queue one by one.
 *  The packet is either passed to another module or released on error.
 *  @param[in] device_id The source device identifier.
 *  @param[in,out] packet The received packet.
 *  @returns EOK on success and the packet is no longer needed.
 *  @returns EINVAL if the packet is too small to carry the IP packet.
 *  @returns EINVAL if the received address lengths differs from the registered values.
 *  @returns ENOENT if the device is not found in the cache.
 *  @returns ENOENT if the protocol for the device is not found in the cache.
 *  @returns ENOMEM if there is not enough memory left.
 */
int ip_receive_message(device_id_t device_id, packet_t packet);

/** Processes the received packet.
 *  The packet is either passed to another module or released on error.
 *  The ICMP_PARAM_POINTER error notification may be sent if the checksum is invalid.
 *  The ICMP_EXC_TTL error notification may be sent if the TTL is less than two (2).
 *  The ICMP_HOST_UNREACH error notification may be sent if no route was found.
 *  The ICMP_HOST_UNREACH error notification may be sent if the packet is for another host and the routing is disabled.
 *  @param[in] device_id The source device identifier.
 *  @param[in] packet The received packet to be processed.
 *  @returns EOK on success.
 *  @returns EINVAL if the TTL is less than two (2).
 *  @returns EINVAL if the checksum is invalid.
 *  @returns EAFNOSUPPORT if the address family is not supported.
 *  @returns ENOENT if no route was found.
 *  @returns ENOENT if the packet is for another host and the routing is disabled.
 */
int ip_process_packet(device_id_t device_id, packet_t packet);

/** Returns the packet destination address from the IP header.
 *  @param[in] header The packet IP header to be read.
 *  @returns The packet destination address.
 */
in_addr_t ip_get_destination(ip_header_ref header);

/** Delivers the packet to the local host.
 *  The packet is either passed to another module or released on error.
 *  The ICMP_PROT_UNREACH error notification may be sent if the protocol is not found.
 *  @param[in] device_id The source device identifier.
 *  @param[in] packet The packet to be delivered.
 *  @param[in] header The first packet IP header. May be NULL.
 *  @param[in] error The packet error service.
 *  @returns EOK on success.
 *  @returns ENOTSUP if the packet is a fragment.
 *  @returns EAFNOSUPPORT if the address family is not supported.
 *  @returns ENOENT if the target protocol is not found.
 *  @returns Other error codes as defined for the packet_set_addr() function.
 *  @returns Other error codes as defined for the packet_trim() function.
 *  @returns Other error codes as defined for the protocol specific tl_received_msg function.
 */
int ip_deliver_local(device_id_t device_id, packet_t packet, ip_header_ref header, services_t error);

/** Prepares the ICMP notification packet.
 *  Releases additional packets and keeps only the first one.
 *  All packets is released on error.
 *  @param[in] error The packet error service.
 *  @param[in] packet The packet or the packet queue to be reported as faulty.
 *  @param[in] header The first packet IP header. May be NULL.
 *  @returns The found ICMP phone.
 *  @returns EINVAL if the error parameter is set.
 *  @returns EINVAL if the ICMP phone is not found.
 *  @returns EINVAL if the ip_prepare_icmp() fails.
 */
int ip_prepare_icmp_and_get_phone(services_t error, packet_t packet, ip_header_ref header);

/** Returns the ICMP phone.
 *  Searches the registered protocols.
 *  @returns The found ICMP phone.
 *  @returns ENOENT if the ICMP is not registered.
 */
int ip_get_icmp_phone(void);

/** Prepares the ICMP notification packet.
 *  Releases additional packets and keeps only the first one.
 *  @param[in] packet The packet or the packet queue to be reported as faulty.
 *  @param[in] header The first packet IP header. May be NULL.
 *  @returns EOK on success.
 *  @returns EINVAL if there are no data in the packet.
 *  @returns EINVAL if the packet is a fragment.
 *  @returns ENOMEM if the packet is too short to contain the IP header.
 *  @returns EAFNOSUPPORT if the address family is not supported.
 *  @returns EPERM if the protocol is not allowed to send ICMP notifications. The ICMP protocol itself.
 *  @returns Other error codes as defined for the packet_set_addr().
 */
int ip_prepare_icmp(packet_t packet, ip_header_ref header);

/** 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 ip_release_and_return(packet_t packet, int result);

int ip_initialize(async_client_conn_t client_connection){
        ERROR_DECLARE;

        fibril_rwlock_initialize(&ip_globals.lock);
        fibril_rwlock_write_lock(&ip_globals.lock);
        fibril_rwlock_initialize(&ip_globals.protos_lock);
        fibril_rwlock_initialize(&ip_globals.netifs_lock);
        ip_globals.packet_counter = 0;
        ip_globals.gateway.address.s_addr = 0;
        ip_globals.gateway.netmask.s_addr = 0;
        ip_globals.gateway.gateway.s_addr = 0;
        ip_globals.gateway.netif = NULL;
        ERROR_PROPAGATE(ip_netifs_initialize(&ip_globals.netifs));
        ERROR_PROPAGATE(ip_protos_initialize(&ip_globals.protos));
        ip_globals.client_connection = client_connection;
        ERROR_PROPAGATE(modules_initialize(&ip_globals.modules));
        ERROR_PROPAGATE(add_module(NULL, &ip_globals.modules, ARP_NAME, ARP_FILENAME, SERVICE_ARP, arp_task_get_id(), arp_connect_module));
        fibril_rwlock_write_unlock(&ip_globals.lock);
        return EOK;
}

int ip_device_req(int il_phone, device_id_t device_id, services_t netif){
        ERROR_DECLARE;

        ip_netif_ref ip_netif;
        ip_route_ref route;
        int index;
        char * data;

        ip_netif = (ip_netif_ref) malloc(sizeof(ip_netif_t));
        if(! ip_netif){
                return ENOMEM;
        }
        if(ERROR_OCCURRED(ip_routes_initialize(&ip_netif->routes))){
                free(ip_netif);
                return ERROR_CODE;
        }
        ip_netif->device_id = device_id;
        ip_netif->service = netif;
        ip_netif->state = NETIF_STOPPED;
        fibril_rwlock_write_lock(&ip_globals.netifs_lock);
        if(ERROR_OCCURRED(ip_netif_initialize(ip_netif))){
                fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
                ip_routes_destroy(&ip_netif->routes);
                free(ip_netif);
                return ERROR_CODE;
        }
        if(ip_netif->arp){
                ++ ip_netif->arp->usage;
        }
        // print the settings
        printf("New device registered:\n\tid\t= %d\n\tphone\t= %d\n\tIPV\t= %d\n", ip_netif->device_id, ip_netif->phone, ip_netif->ipv);
        printf("\tconfiguration\t= %s\n", ip_netif->dhcp ? "dhcp" : "static");
        // TODO ipv6 addresses
        data = (char *) malloc(INET_ADDRSTRLEN);
        if(data){
                for(index = 0; index < ip_routes_count(&ip_netif->routes); ++ index){
                        route = ip_routes_get_index(&ip_netif->routes, index);
                        if(route){
                                printf("\tRouting %d:\n", index);
                                inet_ntop(AF_INET, (uint8_t *) &route->address.s_addr, data, INET_ADDRSTRLEN);
                                printf("\t\taddress\t= %s\n", data);
                                inet_ntop(AF_INET, (uint8_t *) &route->netmask.s_addr, data, INET_ADDRSTRLEN);
                                printf("\t\tnetmask\t= %s\n", data);
                                inet_ntop(AF_INET, (uint8_t *) &route->gateway.s_addr, data, INET_ADDRSTRLEN);
                                printf("\t\tgateway\t= %s\n", data);
                        }
                }
                inet_ntop(AF_INET, (uint8_t *) &ip_netif->broadcast.s_addr, data, INET_ADDRSTRLEN);
                printf("\t\tbroadcast\t= %s\n", data);
                free(data);
        }
        fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
        return EOK;
}

int ip_netif_initialize(ip_netif_ref ip_netif){
        ERROR_DECLARE;

        measured_string_t names[] = {{str_dup("IPV"), 3}, {str_dup("IP_CONFIG"), 9}, {str_dup("IP_ADDR"), 7}, {str_dup("IP_NETMASK"), 10}, {str_dup("IP_GATEWAY"), 10}, {str_dup("IP_BROADCAST"), 12}, {str_dup("ARP"), 3}, {str_dup("IP_ROUTING"), 10}};
        measured_string_ref configuration;
        size_t count = sizeof(names) / sizeof(measured_string_t);
        char * data;
        measured_string_t address;
        int index;
        ip_route_ref route;
        in_addr_t gateway;

        ip_netif->arp = NULL;
        route = NULL;
        ip_netif->ipv = NET_DEFAULT_IPV;
        ip_netif->dhcp = false;
        ip_netif->routing = NET_DEFAULT_IP_ROUTING;
        configuration = &names[0];
        // get configuration
        ERROR_PROPAGATE(net_get_device_conf_req(ip_globals.net_phone, ip_netif->device_id, &configuration, count, &data));
        if(configuration){
                if(configuration[0].value){
                        ip_netif->ipv = strtol(configuration[0].value, NULL, 0);
                }
                ip_netif->dhcp = ! str_lcmp(configuration[1].value, "dhcp", configuration[1].length);
                if(ip_netif->dhcp){
                        // TODO dhcp
                        net_free_settings(configuration, data);
                        return ENOTSUP;
                }else if(ip_netif->ipv == IPV4){
                        route = (ip_route_ref) malloc(sizeof(ip_route_t));
                        if(! route){
                                net_free_settings(configuration, data);
                                return ENOMEM;
                        }
                        route->address.s_addr = 0;
                        route->netmask.s_addr = 0;
                        route->gateway.s_addr = 0;
                        route->netif = ip_netif;
                        index = ip_routes_add(&ip_netif->routes, route);
                        if(index < 0){
                                net_free_settings(configuration, data);
                                free(route);
                                return index;
                        }
                        if(ERROR_OCCURRED(inet_pton(AF_INET, configuration[2].value, (uint8_t *) &route->address.s_addr))
                                || ERROR_OCCURRED(inet_pton(AF_INET, configuration[3].value, (uint8_t *) &route->netmask.s_addr))
                                || (inet_pton(AF_INET, configuration[4].value, (uint8_t *) &gateway.s_addr) == EINVAL)
                                || (inet_pton(AF_INET, configuration[5].value, (uint8_t *) &ip_netif->broadcast.s_addr) == EINVAL)){
                                net_free_settings(configuration, data);
                                return EINVAL;
                        }
                }else{
                        // TODO ipv6 in separate module
                        net_free_settings(configuration, data);
                        return ENOTSUP;
                }
                if(configuration[6].value){
                        ip_netif->arp = get_running_module(&ip_globals.modules, configuration[6].value);
                        if(! ip_netif->arp){
                                printf("Failed to start the arp %s\n", configuration[6].value);
                                net_free_settings(configuration, data);
                                return EINVAL;
                        }
                }
                if(configuration[7].value){
                        ip_netif->routing = (configuration[7].value[0] == 'y');
                }
                net_free_settings(configuration, data);
        }
        // binds the netif service which also initializes the device
        ip_netif->phone = nil_bind_service(ip_netif->service, (ipcarg_t) ip_netif->device_id, SERVICE_IP, ip_globals.client_connection);
        if(ip_netif->phone < 0){
                printf("Failed to contact the nil service %d\n", ip_netif->service);
                return ip_netif->phone;
        }
        // has to be after the device netif module initialization
        if(ip_netif->arp){
                if(route){
                        address.value = (char *) &route->address.s_addr;
                        address.length = CONVERT_SIZE(in_addr_t, char, 1);
                        ERROR_PROPAGATE(arp_device_req(ip_netif->arp->phone, ip_netif->device_id, SERVICE_IP, ip_netif->service, &address));
                }else{
                        ip_netif->arp = 0;
                }
        }
        // get packet dimensions
        ERROR_PROPAGATE(nil_packet_size_req(ip_netif->phone, ip_netif->device_id, &ip_netif->packet_dimension));
        if(ip_netif->packet_dimension.content < IP_MIN_CONTENT){
                printf("Maximum transmission unit %d bytes is too small, at least %d bytes are needed\n", ip_netif->packet_dimension.content, IP_MIN_CONTENT);
                ip_netif->packet_dimension.content = IP_MIN_CONTENT;
        }
        index = ip_netifs_add(&ip_globals.netifs, ip_netif->device_id, ip_netif);
        if(index < 0){
                return index;
        }
        if(gateway.s_addr){
                // the default gateway
                ip_globals.gateway.address.s_addr = 0;
                ip_globals.gateway.netmask.s_addr = 0;
                ip_globals.gateway.gateway.s_addr = gateway.s_addr;
                ip_globals.gateway.netif = ip_netif;
        }
        return EOK;
}

int ip_mtu_changed_message(device_id_t device_id, size_t mtu){
        ip_netif_ref netif;

        fibril_rwlock_write_lock(&ip_globals.netifs_lock);
        netif = ip_netifs_find(&ip_globals.netifs, device_id);
        if(! netif){
                fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
                return ENOENT;
        }
        netif->packet_dimension.content = mtu;
        printf("ip - device %d changed mtu to %d\n\n", device_id, mtu);
        fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
        return EOK;
}

int ip_device_state_message(device_id_t device_id, device_state_t state){
        ip_netif_ref netif;

        fibril_rwlock_write_lock(&ip_globals.netifs_lock);
        // find the device
        netif = ip_netifs_find(&ip_globals.netifs, device_id);
        if(! netif){
                fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
                return ENOENT;
        }
        netif->state = state;
        printf("ip - device %d changed state to %d\n\n", device_id, state);
        fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
        return EOK;
}

int ip_connect_module(services_t service){
        return EOK;
}

int ip_bind_service(services_t service, int protocol, services_t me, async_client_conn_t receiver, tl_received_msg_t received_msg){
        return ip_register(protocol, me, 0, received_msg);
}

int ip_register(int protocol, services_t service, int phone, tl_received_msg_t received_msg){
        ip_proto_ref proto;
        int index;

        if(!(protocol && service && ((phone > 0) || (received_msg)))){
                return EINVAL;
        }
        proto = (ip_proto_ref) malloc(sizeof(ip_protos_t));
        if(! proto){
                return ENOMEM;
        }
        proto->protocol = protocol;
        proto->service = service;
        proto->phone = phone;
        proto->received_msg = received_msg;
        fibril_rwlock_write_lock(&ip_globals.protos_lock);
        index = ip_protos_add(&ip_globals.protos, proto->protocol, proto);
        if(index < 0){
                fibril_rwlock_write_unlock(&ip_globals.protos_lock);
                free(proto);
                return index;
        }
        printf("New protocol registered:\n\tprotocol\t= %d\n\tphone\t= %d\n", proto->protocol, proto->phone);
        fibril_rwlock_write_unlock(&ip_globals.protos_lock);
        return EOK;
}

int ip_send_msg(int il_phone, device_id_t device_id, packet_t packet, services_t sender, services_t error){
        ERROR_DECLARE;

        int addrlen;
        ip_netif_ref netif;
        ip_route_ref route;
        struct sockaddr * addr;
        struct sockaddr_in * address_in;
//      struct sockaddr_in6 *   address_in6;
        in_addr_t * dest;
        in_addr_t * src;
        int phone;

        // addresses in the host byte order
        // should be the next hop address or the target destination address
        addrlen = packet_get_addr(packet, NULL, (uint8_t **) &addr);
        if(addrlen < 0){
                return ip_release_and_return(packet, addrlen);
        }
        if((size_t) addrlen < sizeof(struct sockaddr)){
                return ip_release_and_return(packet, EINVAL);
        }
        switch(addr->sa_family){
                case AF_INET:
                        if(addrlen != sizeof(struct sockaddr_in)){
                                return ip_release_and_return(packet, EINVAL);
                        }
                        address_in = (struct sockaddr_in *) addr;
                        dest = &address_in->sin_addr;
                        if(! dest->s_addr){
                                dest->s_addr = IPV4_LOCALHOST_ADDRESS;
                        }
                        break;
                // TODO IPv6
/*              case AF_INET6:
                        if(addrlen != sizeof(struct sockaddr_in6)){
                                return EINVAL;
                        }
                        address_in6 = (struct sockaddr_in6 *) dest;
                        address_in6.sin6_addr.s6_addr;
                        IPV6_LOCALHOST_ADDRESS;
*/              default:
                        return ip_release_and_return(packet, EAFNOSUPPORT);
        }
        netif = NULL;
        route = NULL;
        fibril_rwlock_read_lock(&ip_globals.netifs_lock);
        // device specified?
        if(device_id > 0){
                netif = ip_netifs_find(&ip_globals.netifs, device_id);
                route = ip_netif_find_route(netif, * dest);
                if(netif && (! route) && (ip_globals.gateway.netif == netif)){
                        route = &ip_globals.gateway;
                }
        }
        if(! route){
                route = ip_find_route(*dest);
                netif = route ? route->netif : NULL;
        }
        if(!(netif && route)){
                fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
                phone = ip_prepare_icmp_and_get_phone(error, packet, NULL);
                if(phone >= 0){
                        // unreachable ICMP if no routing
                        icmp_destination_unreachable_msg(phone, ICMP_NET_UNREACH, 0, packet);
                }
                return ENOENT;
        }
        if(error){
                // do not send for broadcast, anycast packets or network broadcast
                if((! dest->s_addr)
                        || (!(~ dest->s_addr))
                        || (!(~((dest->s_addr &(~ route->netmask.s_addr)) | route->netmask.s_addr)))
                        || (!(dest->s_addr &(~ route->netmask.s_addr)))){
                        return ip_release_and_return(packet, EINVAL);
                }
        }
        // if the local host is the destination
        if((route->address.s_addr == dest->s_addr)
                && (dest->s_addr != IPV4_LOCALHOST_ADDRESS)){
                // find the loopback device to deliver
                dest->s_addr = IPV4_LOCALHOST_ADDRESS;
                route = ip_find_route(*dest);
                netif = route ? route->netif : NULL;
                if(!(netif && route)){
                        fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
                        phone = ip_prepare_icmp_and_get_phone(error, packet, NULL);
                        if(phone >= 0){
                                // unreachable ICMP if no routing
                                icmp_destination_unreachable_msg(phone, ICMP_HOST_UNREACH, 0, packet);
                        }
                        return ENOENT;
                }
        }
        src = ip_netif_address(netif);
        if(! src){
                fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
                return ip_release_and_return(packet, ENOENT);
        }
        ERROR_CODE = ip_send_route(packet, netif, route, src, * dest, error);
        fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
        return ERROR_CODE;
}

in_addr_t * ip_netif_address(ip_netif_ref netif){
        ip_route_ref route;

        route = ip_routes_get_index(&netif->routes, 0);
        return route ? &route->address : NULL;
}

int ip_send_route(packet_t packet, ip_netif_ref netif, ip_route_ref route, in_addr_t * src, in_addr_t dest, services_t error){
        ERROR_DECLARE;

        measured_string_t destination;
        measured_string_ref translation;
        char * data;
        int phone;

        // get destination hardware address
        if(netif->arp && (route->address.s_addr != dest.s_addr)){
                destination.value = route->gateway.s_addr ? (char *) &route->gateway.s_addr : (char *) &dest.s_addr;
                destination.length = CONVERT_SIZE(dest.s_addr, char, 1);
                if(ERROR_OCCURRED(arp_translate_req(netif->arp->phone, netif->device_id, SERVICE_IP, &destination, &translation, &data))){
//                      sleep(1);
//                      ERROR_PROPAGATE(arp_translate_req(netif->arp->phone, netif->device_id, SERVICE_IP, &destination, &translation, &data));
                        pq_release(ip_globals.net_phone, packet_get_id(packet));
                        return ERROR_CODE;
                }
                if(!(translation && translation->value)){
                        if(translation){
                                free(translation);
                                free(data);
                        }
                        phone = ip_prepare_icmp_and_get_phone(error, packet, NULL);
                        if(phone >= 0){
                                // unreachable ICMP if no routing
                                icmp_destination_unreachable_msg(phone, ICMP_HOST_UNREACH, 0, packet);
                        }
                        return EINVAL;
                }
        }else translation = NULL;
        if(ERROR_OCCURRED(ip_prepare_packet(src, dest, packet, translation))){
                pq_release(ip_globals.net_phone, packet_get_id(packet));
        }else{
                packet = ip_split_packet(packet, netif->packet_dimension.prefix, netif->packet_dimension.content, netif->packet_dimension.suffix, netif->packet_dimension.addr_len, error);
                if(packet){
                        nil_send_msg(netif->phone, netif->device_id, packet, SERVICE_IP);
                }
        }
        if(translation){
                free(translation);
                free(data);
        }
        return ERROR_CODE;
}

int ip_prepare_packet(in_addr_t * source, in_addr_t dest, packet_t packet, measured_string_ref destination){
        ERROR_DECLARE;

        size_t length;
        ip_header_ref header;
        ip_header_ref last_header;
        ip_header_ref middle_header;
        packet_t next;

        length = packet_get_data_length(packet);
        if((length < sizeof(ip_header_t)) || (length > IP_MAX_CONTENT)){
                return EINVAL;
        }
        header = (ip_header_ref) packet_get_data(packet);
        if(destination){
                ERROR_PROPAGATE(packet_set_addr(packet, NULL, (uint8_t *) destination->value, CONVERT_SIZE(char, uint8_t, destination->length)));
        }else{
                ERROR_PROPAGATE(packet_set_addr(packet, NULL, NULL, 0));
        }
        header->version = IPV4;
        header->fragment_offset_high = 0;
        header->fragment_offset_low = 0;
        header->header_checksum = 0;
        if(source){
                header->source_address = source->s_addr;
        }
        header->destination_address = dest.s_addr;
        fibril_rwlock_write_lock(&ip_globals.lock);
        ++ ip_globals.packet_counter;
        header->identification = htons(ip_globals.packet_counter);
        fibril_rwlock_write_unlock(&ip_globals.lock);
//      length = packet_get_data_length(packet);
        if(pq_next(packet)){
                last_header = (ip_header_ref) malloc(IP_HEADER_LENGTH(header));
                if(! last_header){
                        return ENOMEM;
                }
                ip_create_last_header(last_header, header);
                next = pq_next(packet);
                while(pq_next(next)){
                        middle_header = (ip_header_ref) packet_prefix(next, IP_HEADER_LENGTH(last_header));
                        if(! middle_header){
                                return ENOMEM;
                        }
                        memcpy(middle_header, last_header, IP_HEADER_LENGTH(last_header));
                        header->flags |= IPFLAG_MORE_FRAGMENTS;
                        middle_header->total_length = htons(packet_get_data_length(next));
                        middle_header->fragment_offset_high = IP_COMPUTE_FRAGMENT_OFFSET_HIGH(length);
                        middle_header->fragment_offset_low = IP_COMPUTE_FRAGMENT_OFFSET_LOW(length);
                        middle_header->header_checksum = IP_HEADER_CHECKSUM(middle_header);
                        if(destination){
                                ERROR_PROPAGATE(packet_set_addr(next, NULL, (uint8_t *) destination->value, CONVERT_SIZE(char, uint8_t, destination->length)));
                        }
                        length += packet_get_data_length(next);
                        next = pq_next(next);
                }
                middle_header = (ip_header_ref) packet_prefix(next, IP_HEADER_LENGTH(last_header));
                if(! middle_header){
                        return ENOMEM;
                }
                memcpy(middle_header, last_header, IP_HEADER_LENGTH(last_header));
                middle_header->total_length = htons(packet_get_data_length(next));
                middle_header->fragment_offset_high = IP_COMPUTE_FRAGMENT_OFFSET_HIGH(length);
                middle_header->fragment_offset_low = IP_COMPUTE_FRAGMENT_OFFSET_LOW(length);
                middle_header->header_checksum = IP_HEADER_CHECKSUM(middle_header);
                if(destination){
                        ERROR_PROPAGATE(packet_set_addr(next, NULL, (uint8_t *) destination->value, CONVERT_SIZE(char, uint8_t, destination->length)));
                }
                length += packet_get_data_length(next);
                free(last_header);
                header->flags |= IPFLAG_MORE_FRAGMENTS;
        }
        header->total_length = htons(length);
        // unnecessary for all protocols
        header->header_checksum = IP_HEADER_CHECKSUM(header);
        return EOK;
}

int ip_message(ipc_callid_t callid, ipc_call_t * call, ipc_call_t * answer, int * answer_count){
        ERROR_DECLARE;

        packet_t packet;
        struct sockaddr * addr;
        size_t addrlen;
        ip_pseudo_header_ref header;
        size_t headerlen;
        device_id_t device_id;

        *answer_count = 0;
        switch(IPC_GET_METHOD(*call)){
                case IPC_M_PHONE_HUNGUP:
                        return EOK;
                case NET_IL_DEVICE:
                        return ip_device_req(0, IPC_GET_DEVICE(call), IPC_GET_SERVICE(call));
                case IPC_M_CONNECT_TO_ME:
                        return ip_register(IL_GET_PROTO(call), IL_GET_SERVICE(call), IPC_GET_PHONE(call), NULL);
                case NET_IL_SEND:
                        ERROR_PROPAGATE(packet_translate(ip_globals.net_phone, &packet, IPC_GET_PACKET(call)));
                        return ip_send_msg(0, IPC_GET_DEVICE(call), packet, 0, IPC_GET_ERROR(call));
                case NET_IL_DEVICE_STATE:
                        return ip_device_state_message(IPC_GET_DEVICE(call), IPC_GET_STATE(call));
                case NET_IL_RECEIVED:
                        ERROR_PROPAGATE(packet_translate(ip_globals.net_phone, &packet, IPC_GET_PACKET(call)));
                        return ip_receive_message(IPC_GET_DEVICE(call), packet);
                case NET_IP_RECEIVED_ERROR:
                        ERROR_PROPAGATE(packet_translate(ip_globals.net_phone, &packet, IPC_GET_PACKET(call)));
                        return ip_received_error_msg(0, IPC_GET_DEVICE(call), packet, IPC_GET_TARGET(call), IPC_GET_ERROR(call));
                case NET_IP_ADD_ROUTE:
                        return ip_add_route_req(0, IPC_GET_DEVICE(call), IP_GET_ADDRESS(call), IP_GET_NETMASK(call), IP_GET_GATEWAY(call));
                case NET_IP_SET_GATEWAY:
                        return ip_set_gateway_req(0, IPC_GET_DEVICE(call), IP_GET_GATEWAY(call));
                case NET_IP_GET_ROUTE:
                        ERROR_PROPAGATE(data_receive((void **) &addr, &addrlen));
                        ERROR_PROPAGATE(ip_get_route_req(0, IP_GET_PROTOCOL(call), addr, (socklen_t) addrlen,
                            &device_id, &header, &headerlen));
                        *IPC_SET_DEVICE(answer) = device_id;
                        *IP_SET_HEADERLEN(answer) = headerlen;
                        *answer_count = 2;
                        if(! ERROR_OCCURRED(data_reply(&headerlen, sizeof(headerlen)))){
                                ERROR_CODE = data_reply(header, headerlen);
                        }
                        free(header);
                        return ERROR_CODE;
                case NET_IL_PACKET_SPACE:
                        ERROR_PROPAGATE(ip_packet_size_message(IPC_GET_DEVICE(call), IPC_SET_ADDR(answer), IPC_SET_PREFIX(answer), IPC_SET_CONTENT(answer), IPC_SET_SUFFIX(answer)));
                        *answer_count = 3;
                        return EOK;
                case NET_IL_MTU_CHANGED:
                        return ip_mtu_changed_message(IPC_GET_DEVICE(call), IPC_GET_MTU(call));
        }
        return ENOTSUP;
}

int ip_packet_size_req(int ip_phone, device_id_t device_id, packet_dimension_ref packet_dimension){
        if(! packet_dimension){
                return EBADMEM;
        }
        return ip_packet_size_message(device_id, &packet_dimension->addr_len, &packet_dimension->prefix, &packet_dimension->content, &packet_dimension->suffix);
}

int ip_packet_size_message(device_id_t device_id, size_t * addr_len, size_t * prefix, size_t * content, size_t * suffix){
        ip_netif_ref netif;
        int index;

        if(!(addr_len && prefix && content && suffix)){
                return EBADMEM;
        }
        *content = IP_MAX_CONTENT - IP_PREFIX;
        fibril_rwlock_read_lock(&ip_globals.netifs_lock);
        if(device_id < 0){
                *addr_len = IP_ADDR;
                *prefix = 0;
                *suffix = 0;
                for(index = ip_netifs_count(&ip_globals.netifs) - 1; index >= 0; -- index){
                        netif = ip_netifs_get_index(&ip_globals.netifs, index);
                        if(netif){
                                if(netif->packet_dimension.addr_len > * addr_len){
                                        *addr_len = netif->packet_dimension.addr_len;
                                }
                                if(netif->packet_dimension.prefix > * prefix){
                                        *prefix = netif->packet_dimension.prefix;
                                }
                                if(netif->packet_dimension.suffix > * suffix){
                                        *suffix = netif->packet_dimension.suffix;
                                }
                        }
                }
                *prefix = * prefix + IP_PREFIX;
                *suffix = * suffix + IP_SUFFIX;
        }else{
                netif = ip_netifs_find(&ip_globals.netifs, device_id);
                if(! netif){
                        fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
                        return ENOENT;
                }
                *addr_len = (netif->packet_dimension.addr_len > IP_ADDR) ? netif->packet_dimension.addr_len : IP_ADDR;
                *prefix = netif->packet_dimension.prefix + IP_PREFIX;
                *suffix = netif->packet_dimension.suffix + IP_SUFFIX;
        }
        fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
        return EOK;
}

int ip_add_route_req(int ip_phone, device_id_t device_id, in_addr_t address, in_addr_t netmask, in_addr_t gateway){
        ip_route_ref route;
        ip_netif_ref netif;
        int index;

        fibril_rwlock_write_lock(&ip_globals.netifs_lock);
        netif = ip_netifs_find(&ip_globals.netifs, device_id);
        if(! netif){
                fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
                return ENOENT;
        }
        route = (ip_route_ref) malloc(sizeof(ip_route_t));
        if(! route){
                fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
                return ENOMEM;
        }
        route->address.s_addr = address.s_addr;
        route->netmask.s_addr = netmask.s_addr;
        route->gateway.s_addr = gateway.s_addr;
        route->netif = netif;
        index = ip_routes_add(&netif->routes, route);
        if(index < 0){
                free(route);
        }
        fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
        return index;
}

ip_route_ref ip_find_route(in_addr_t destination){
        int index;
        ip_route_ref route;
        ip_netif_ref netif;

        // start with the last netif - the newest one
        index = ip_netifs_count(&ip_globals.netifs) - 1;
        while(index >= 0){
                netif = ip_netifs_get_index(&ip_globals.netifs, index);
                if(netif && (netif->state == NETIF_ACTIVE)){
                        route = ip_netif_find_route(netif, destination);
                        if(route){
                                return route;
                        }
                }
                -- index;
        }
        return &ip_globals.gateway;
}

ip_route_ref ip_netif_find_route(ip_netif_ref netif, in_addr_t destination){
        int index;
        ip_route_ref route;

        if(netif){
                // start with the first one - the direct route
                for(index = 0; index < ip_routes_count(&netif->routes); ++ index){
                        route = ip_routes_get_index(&netif->routes, index);
                        if(route && ((route->address.s_addr &route->netmask.s_addr) == (destination.s_addr &route->netmask.s_addr))){
                                return route;
                        }
                }
        }
        return NULL;
}

int ip_set_gateway_req(int ip_phone, device_id_t device_id, in_addr_t gateway){
        ip_netif_ref netif;

        fibril_rwlock_write_lock(&ip_globals.netifs_lock);
        netif = ip_netifs_find(&ip_globals.netifs, device_id);
        if(! netif){
                fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
                return ENOENT;
        }
        ip_globals.gateway.address.s_addr = 0;
        ip_globals.gateway.netmask.s_addr = 0;
        ip_globals.gateway.gateway.s_addr = gateway.s_addr;
        ip_globals.gateway.netif = netif;
        fibril_rwlock_write_unlock(&ip_globals.netifs_lock);
        return EOK;
}

packet_t ip_split_packet(packet_t packet, size_t prefix, size_t content, size_t suffix, socklen_t addr_len, services_t error){
        size_t length;
        packet_t next;
        packet_t new_packet;
        int result;
        int phone;

        next = packet;
        // check all packets
        while(next){
                length = packet_get_data_length(next);
                // too long?
                if(length > content){
                        result = ip_fragment_packet(next, content, prefix, suffix, addr_len);
                        if(result != EOK){
                                new_packet = pq_detach(next);
                                if(next == packet){
                                        // the new first packet of the queue
                                        packet = new_packet;
                                }
                                // fragmentation needed?
                                if(result == EPERM){
                                        phone = ip_prepare_icmp_and_get_phone(error, next, NULL);
                                        if(phone >= 0){
                                                // fragmentation necessary ICMP
                                                icmp_destination_unreachable_msg(phone, ICMP_FRAG_NEEDED, content, next);
                                        }
                                }else{
                                        pq_release(ip_globals.net_phone, packet_get_id(next));
                                }
                                next = new_packet;
                                continue;
                        }
                }
                next = pq_next(next);
        }
        return packet;
}

int ip_fragment_packet(packet_t packet, size_t length, size_t prefix, size_t suffix, socklen_t addr_len){
        ERROR_DECLARE;

        packet_t new_packet;
        ip_header_ref header;
        ip_header_ref middle_header;
        ip_header_ref last_header;
        struct sockaddr * src;
        struct sockaddr * dest;
        socklen_t addrlen;
        int result;

        result = packet_get_addr(packet, (uint8_t **) &src, (uint8_t **) &dest);
        if(result <= 0){
                return EINVAL;
        }
        addrlen = (socklen_t) result;
        if(packet_get_data_length(packet) <= sizeof(ip_header_t)){
                return ENOMEM;
        }
        // get header
        header = (ip_header_ref) packet_get_data(packet);
        if(! header){
                return EINVAL;
        }
        // fragmentation forbidden?
        if(header->flags &IPFLAG_DONT_FRAGMENT){
                return EPERM;
        }
        // create the last fragment
        new_packet = packet_get_4(ip_globals.net_phone, prefix, length, suffix, ((addrlen > addr_len) ? addrlen : addr_len));
        if(! new_packet){
                return ENOMEM;
        }
        // allocate as much as originally
        last_header = (ip_header_ref) packet_suffix(new_packet, IP_HEADER_LENGTH(header));
        if(! last_header){
                return ip_release_and_return(packet, ENOMEM);
        }
        ip_create_last_header(last_header, header);
        // trim the unused space
        if(ERROR_OCCURRED(packet_trim(new_packet, 0, IP_HEADER_LENGTH(header) - IP_HEADER_LENGTH(last_header)))){
                return ip_release_and_return(packet, ERROR_CODE);
        }
        // biggest multiple of 8 lower than content
        // TODO even fragmentation?
        length = length &(~ 0x7);// (content / 8) * 8
        if(ERROR_OCCURRED(ip_fragment_packet_data(packet, new_packet, header, last_header, ((IP_HEADER_DATA_LENGTH(header) - ((length - IP_HEADER_LENGTH(header)) &(~ 0x7))) % ((length - IP_HEADER_LENGTH(last_header)) &(~ 0x7))), src, dest, addrlen))){
                return ip_release_and_return(packet, ERROR_CODE);
        }
        // mark the first as fragmented
        header->flags |= IPFLAG_MORE_FRAGMENTS;
        // create middle framgents
        while(IP_TOTAL_LENGTH(header) > length){
                new_packet = packet_get_4(ip_globals.net_phone, prefix, length, suffix, ((addrlen >= addr_len) ? addrlen : addr_len));
                if(! new_packet){
                        return ENOMEM;
                }
                middle_header = ip_create_middle_header(new_packet, last_header);
                if(! middle_header){
                        return ip_release_and_return(packet, ENOMEM);
                }
                if(ERROR_OCCURRED(ip_fragment_packet_data(packet, new_packet, header, middle_header, (length - IP_HEADER_LENGTH(middle_header)) &(~ 0x7), src, dest, addrlen))){
                        return ip_release_and_return(packet, ERROR_CODE);
                }
        }
        // finish the first fragment
        header->header_checksum = IP_HEADER_CHECKSUM(header);
        return EOK;
}

int ip_fragment_packet_data(packet_t packet, packet_t new_packet, ip_header_ref header, ip_header_ref new_header, size_t length, const struct sockaddr * src, const struct sockaddr * dest, socklen_t addrlen){
        ERROR_DECLARE;

        void * data;
        size_t offset;

        data = packet_suffix(new_packet, length);
        if(! data){
                return ENOMEM;
        }
        memcpy(data, ((void *) header) + IP_TOTAL_LENGTH(header) - length, length);
        ERROR_PROPAGATE(packet_trim(packet, 0, length));
        header->total_length = htons(IP_TOTAL_LENGTH(header) - length);
        new_header->total_length = htons(IP_HEADER_LENGTH(new_header) + length);
        offset = IP_FRAGMENT_OFFSET(header) + IP_HEADER_DATA_LENGTH(header);
        new_header->fragment_offset_high = IP_COMPUTE_FRAGMENT_OFFSET_HIGH(offset);
        new_header->fragment_offset_low = IP_COMPUTE_FRAGMENT_OFFSET_LOW(offset);
        new_header->header_checksum = IP_HEADER_CHECKSUM(new_header);
        ERROR_PROPAGATE(packet_set_addr(new_packet, (const uint8_t *) src, (const uint8_t *) dest, addrlen));
        return pq_insert_after(packet, new_packet);
}

ip_header_ref ip_create_middle_header(packet_t packet, ip_header_ref last){
        ip_header_ref middle;

        middle = (ip_header_ref) packet_suffix(packet, IP_HEADER_LENGTH(last));
        if(! middle){
                return NULL;
        }
        memcpy(middle, last, IP_HEADER_LENGTH(last));
        middle->flags |= IPFLAG_MORE_FRAGMENTS;
        return middle;
}

void ip_create_last_header(ip_header_ref last, ip_header_ref first){
        ip_option_ref option;
        size_t next;
        size_t length;

        // copy first itself
        memcpy(last, first, sizeof(ip_header_t));
        length = sizeof(ip_header_t);
        next = sizeof(ip_header_t);
        // process all ip options
        while(next < first->header_length){
                option = (ip_option_ref) (((uint8_t *) first) + next);
                // skip end or noop
                if((option->type == IPOPT_END) || (option->type == IPOPT_NOOP)){
                        ++ next;
                }else{
                        // copy if said so or skip
                        if(IPOPT_COPIED(option->type)){
                                memcpy(((uint8_t *) last) + length, ((uint8_t *) first) + next, option->length);
                                length += option->length;
                        }
                        // next option
                        next += option->length;
                }
        }
        // align 4 byte boundary
        if(length % 4){
                bzero(((uint8_t *) last) + length, 4 - (length % 4));
                last->header_length = length / 4 + 1;
        }else{
                last->header_length = length / 4;
        }
        last->header_checksum = 0;
}

int ip_receive_message(device_id_t device_id, packet_t packet){
        packet_t next;

        do{
                next = pq_detach(packet);
                ip_process_packet(device_id, packet);
                packet = next;
        }while(packet);
        return EOK;
}

int ip_process_packet(device_id_t device_id, packet_t packet){
        ERROR_DECLARE;

        ip_header_ref header;
        in_addr_t dest;
        ip_route_ref route;
        int phone;
        struct sockaddr * addr;
        struct sockaddr_in addr_in;
//      struct sockaddr_in      addr_in6;
        socklen_t addrlen;

        header = (ip_header_ref) packet_get_data(packet);
        if(! header){
                return ip_release_and_return(packet, ENOMEM);
        }
        // checksum
        if((header->header_checksum) && (IP_HEADER_CHECKSUM(header) != IP_CHECKSUM_ZERO)){
                phone = ip_prepare_icmp_and_get_phone(0, packet, header);
                if(phone >= 0){
                        // checksum error ICMP
                        icmp_parameter_problem_msg(phone, ICMP_PARAM_POINTER, ((size_t) ((void *) &header->header_checksum)) - ((size_t) ((void *) header)), packet);
                }
                return EINVAL;
        }
        if(header->ttl <= 1){
                phone = ip_prepare_icmp_and_get_phone(0, packet, header);
                if(phone >= 0){
                        // ttl oxceeded ICMP
                        icmp_time_exceeded_msg(phone, ICMP_EXC_TTL, packet);
                }
                return EINVAL;
        }
        // process ipopt and get destination
        dest = ip_get_destination(header);
        // set the addrination address
        switch(header->version){
                case IPVERSION:
                        addrlen = sizeof(addr_in);
                        bzero(&addr_in, addrlen);
                        addr_in.sin_family = AF_INET;
                        memcpy(&addr_in.sin_addr.s_addr, &dest, sizeof(dest));
                        addr = (struct sockaddr *) &addr_in;
                        break;
/*              case IPv6VERSION:
                        addrlen = sizeof(dest_in6);
                        bzero(&dest_in6, addrlen);
                        dest_in6.sin6_family = AF_INET6;
                        memcpy(&dest_in6.sin6_addr.s6_addr,);
                        dest = (struct sockaddr *) &dest_in;
                        break;
*/              default:
                        return ip_release_and_return(packet, EAFNOSUPPORT);
        }
        ERROR_PROPAGATE(packet_set_addr(packet, NULL, (uint8_t *) &addr, addrlen));
        route = ip_find_route(dest);
        if(! route){
                phone = ip_prepare_icmp_and_get_phone(0, packet, header);
                if(phone >= 0){
                        // unreachable ICMP
                        icmp_destination_unreachable_msg(phone, ICMP_HOST_UNREACH, 0, packet);
                }
                return ENOENT;
        }
        if(route->address.s_addr == dest.s_addr){
                // local delivery
                return ip_deliver_local(device_id, packet, header, 0);
        }else{
                // only if routing enabled
                if(route->netif->routing){
                        -- header->ttl;
                        return ip_send_route(packet, route->netif, route, NULL, dest, 0);
                }else{
                        phone = ip_prepare_icmp_and_get_phone(0, packet, header);
                        if(phone >= 0){
                                // unreachable ICMP if no routing
                                icmp_destination_unreachable_msg(phone, ICMP_HOST_UNREACH, 0, packet);
                        }
                        return ENOENT;
                }
        }
}

int ip_received_error_msg(int ip_phone, device_id_t device_id, packet_t packet, services_t target, services_t error){
        uint8_t * data;
        int offset;
        icmp_type_t type;
        icmp_code_t code;
        ip_netif_ref netif;
        measured_string_t address;
        ip_route_ref route;
        ip_header_ref header;

        switch(error){
                case SERVICE_ICMP:
                        offset = icmp_client_process_packet(packet, &type, &code, NULL, NULL);
                        if(offset < 0){
                                return ip_release_and_return(packet, ENOMEM);
                        }
                        data = packet_get_data(packet);
                        header = (ip_header_ref)(data + offset);
                        // destination host unreachable?
                        if((type == ICMP_DEST_UNREACH) && (code == ICMP_HOST_UNREACH)){
                                fibril_rwlock_read_lock(&ip_globals.netifs_lock);
                                netif = ip_netifs_find(&ip_globals.netifs, device_id);
                                if(netif && netif->arp){
                                        route = ip_routes_get_index(&netif->routes, 0);
                                        // from the same network?
                                        if(route && ((route->address.s_addr &route->netmask.s_addr) == (header->destination_address &route->netmask.s_addr))){
                                                // clear the ARP mapping if any
                                                address.value = (char *) &header->destination_address;
                                                address.length = CONVERT_SIZE(uint8_t, char, sizeof(header->destination_address));
                                                arp_clear_address_req(netif->arp->phone, netif->device_id, SERVICE_IP, &address);
                                        }
                                }
                                fibril_rwlock_read_unlock(&ip_globals.netifs_lock);
                        }
                        break;
                default:
                        return ip_release_and_return(packet, ENOTSUP);
        }
        return ip_deliver_local(device_id, packet, header, error);
}

int ip_deliver_local(device_id_t device_id, packet_t packet, ip_header_ref header, services_t error){
        ERROR_DECLARE;

        ip_proto_ref proto;
        int phone;
        services_t service;
        tl_received_msg_t received_msg;
        struct sockaddr * src;
        struct sockaddr * dest;
        struct sockaddr_in src_in;
        struct sockaddr_in dest_in;
//      struct sockaddr_in      src_in6;
//      struct sockaddr_in      dest_in6;
        socklen_t addrlen;

        if((header->flags &IPFLAG_MORE_FRAGMENTS) || IP_FRAGMENT_OFFSET(header)){
                // TODO fragmented
                return ENOTSUP;
        }else{
                switch(header->version){
                        case IPVERSION:
                                addrlen = sizeof(src_in);
                                bzero(&src_in, addrlen);
                                src_in.sin_family = AF_INET;
                                memcpy(&dest_in, &src_in, addrlen);
                                memcpy(&src_in.sin_addr.s_addr, &header->source_address, sizeof(header->source_address));
                                memcpy(&dest_in.sin_addr.s_addr, &header->destination_address, sizeof(header->destination_address));
                                src = (struct sockaddr *) &src_in;
                                dest = (struct sockaddr *) &dest_in;
                                break;
/*                      case IPv6VERSION:
                                addrlen = sizeof(src_in6);
                                bzero(&src_in6, addrlen);
                                src_in6.sin6_family = AF_INET6;
                                memcpy(&dest_in6, &src_in6, addrlen);
                                memcpy(&src_in6.sin6_addr.s6_addr,);
                                memcpy(&dest_in6.sin6_addr.s6_addr,);
                                src = (struct sockaddr *) &src_in;
                                dest = (struct sockaddr *) &dest_in;
                                break;
*/                      default:
                                return ip_release_and_return(packet, EAFNOSUPPORT);
                }
                if(ERROR_OCCURRED(packet_set_addr(packet, (uint8_t *) src, (uint8_t *) dest, addrlen))){
                        return ip_release_and_return(packet, ERROR_CODE);
                }
                // trim padding if present
                if((! error) && (IP_TOTAL_LENGTH(header) < packet_get_data_length(packet))){
                        if(ERROR_OCCURRED(packet_trim(packet, 0, packet_get_data_length(packet) - IP_TOTAL_LENGTH(header)))){
                                return ip_release_and_return(packet, ERROR_CODE);
                        }
                }
                fibril_rwlock_read_lock(&ip_globals.protos_lock);
                proto = ip_protos_find(&ip_globals.protos, header->protocol);
                if(! proto){
                        fibril_rwlock_read_unlock(&ip_globals.protos_lock);
                        phone = ip_prepare_icmp_and_get_phone(error, packet, header);
                        if(phone >= 0){
                                // unreachable ICMP
                                icmp_destination_unreachable_msg(phone, ICMP_PROT_UNREACH, 0, packet);
                        }
                        return ENOENT;
                }
                if(proto->received_msg){
                        service = proto->service;
                        received_msg = proto->received_msg;
                        fibril_rwlock_read_unlock(&ip_globals.protos_lock);
                        ERROR_CODE = received_msg(device_id, packet, service, error);
                }else{
                        ERROR_CODE = tl_received_msg(proto->phone, device_id, packet, proto->service, error);
                        fibril_rwlock_read_unlock(&ip_globals.protos_lock);
                }
                return ERROR_CODE;
        }
}

in_addr_t ip_get_destination(ip_header_ref header){
        in_addr_t destination;

        // TODO search set ipopt route?
        destination.s_addr = header->destination_address;
        return destination;
}

int ip_prepare_icmp(packet_t packet, ip_header_ref header){
        packet_t next;
        struct sockaddr * dest;
        struct sockaddr_in dest_in;
//      struct sockaddr_in      dest_in6;
        socklen_t addrlen;

        // detach the first packet and release the others
        next = pq_detach(packet);
        if(next){
                pq_release(ip_globals.net_phone, packet_get_id(next));
        }
        if(! header){
                if(packet_get_data_length(packet) <= sizeof(ip_header_t)){
                        return ENOMEM;
                }
                // get header
                header = (ip_header_ref) packet_get_data(packet);
                if(! header){
                        return EINVAL;
                }
        }
        // only for the first fragment
        if(IP_FRAGMENT_OFFSET(header)){
                return EINVAL;
        }
        // not for the ICMP protocol
        if(header->protocol == IPPROTO_ICMP){
                return EPERM;
        }
        // set the destination address
        switch(header->version){
                case IPVERSION:
                        addrlen = sizeof(dest_in);
                        bzero(&dest_in, addrlen);
                        dest_in.sin_family = AF_INET;
                        memcpy(&dest_in.sin_addr.s_addr, &header->source_address, sizeof(header->source_address));
                        dest = (struct sockaddr *) &dest_in;
                        break;
/*              case IPv6VERSION:
                        addrlen = sizeof(dest_in6);
                        bzero(&dest_in6, addrlen);
                        dest_in6.sin6_family = AF_INET6;
                        memcpy(&dest_in6.sin6_addr.s6_addr,);
                        dest = (struct sockaddr *) &dest_in;
                        break;
*/              default:
                        return EAFNOSUPPORT;
        }
        return packet_set_addr(packet, NULL, (uint8_t *) dest, addrlen);
}

int ip_get_icmp_phone(void){
        ip_proto_ref proto;
        int phone;

        fibril_rwlock_read_lock(&ip_globals.protos_lock);
        proto = ip_protos_find(&ip_globals.protos, IPPROTO_ICMP);
        phone = proto ? proto->phone : ENOENT;
        fibril_rwlock_read_unlock(&ip_globals.protos_lock);
        return phone;
}

int ip_prepare_icmp_and_get_phone(services_t error, packet_t packet, ip_header_ref header){
        int phone;

        phone = ip_get_icmp_phone();
        if(error || (phone < 0) || ip_prepare_icmp(packet, header)){
                return ip_release_and_return(packet, EINVAL);
        }
        return phone;
}

int ip_release_and_return(packet_t packet, int result){
        pq_release(ip_globals.net_phone, packet_get_id(packet));
        return result;
}

int ip_get_route_req(int ip_phone, ip_protocol_t protocol, const struct sockaddr * destination, socklen_t addrlen, device_id_t * device_id, ip_pseudo_header_ref * header, size_t * headerlen){
        struct sockaddr_in * address_in;
//      struct sockaddr_in6 *   address_in6;
        in_addr_t * dest;
        in_addr_t * src;
        ip_route_ref route;
        ipv4_pseudo_header_ref header_in;

        if(!(destination && (addrlen > 0))){
                return EINVAL;
        }
        if(!(device_id && header && headerlen)){
                return EBADMEM;
        }
        if((size_t) addrlen < sizeof(struct sockaddr)){
                return EINVAL;
        }
        switch(destination->sa_family){
                case AF_INET:
                        if(addrlen != sizeof(struct sockaddr_in)){
                                return EINVAL;
                        }
                        address_in = (struct sockaddr_in *) destination;
                        dest = &address_in->sin_addr;
                        if(! dest->s_addr){
                                dest->s_addr = IPV4_LOCALHOST_ADDRESS;
                        }
                        break;
                // TODO IPv6
/*              case AF_INET6:
                        if(addrlen != sizeof(struct sockaddr_in6)){
                                return EINVAL;
                        }
                        address_in6 = (struct sockaddr_in6 *) dest;
                        address_in6.sin6_addr.s6_addr;
*/              default:
                        return EAFNOSUPPORT;
        }
        fibril_rwlock_read_lock(&ip_globals.lock);
        route = ip_find_route(*dest);
        // if the local host is the destination
        if(route && (route->address.s_addr == dest->s_addr)
                && (dest->s_addr != IPV4_LOCALHOST_ADDRESS)){
                // find the loopback device to deliver
                dest->s_addr = IPV4_LOCALHOST_ADDRESS;
                route = ip_find_route(*dest);
        }
        if(!(route && route->netif)){
                fibril_rwlock_read_unlock(&ip_globals.lock);
                return ENOENT;
        }
        *device_id = route->netif->device_id;
        src = ip_netif_address(route->netif);
        fibril_rwlock_read_unlock(&ip_globals.lock);
        *headerlen = sizeof(*header_in);
        header_in = (ipv4_pseudo_header_ref) malloc(*headerlen);
        if(! header_in){
                return ENOMEM;
        }
        bzero(header_in, * headerlen);
        header_in->destination_address = dest->s_addr;
        header_in->source_address = src->s_addr;
        header_in->protocol = protocol;
        header_in->data_length = 0;
        *header = (ip_pseudo_header_ref) header_in;
        return EOK;
}

/** @}
 */