source: mainline/uspace/srv/net/il/arp/arp.c@ 522253c1

/*
 * 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 arp
 *  @{
 */

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

#include <async.h>
#include <malloc.h>
#include <mem.h>
#include <fibril_synch.h>
#include <stdio.h>
#include <str.h>
#include <task.h>
#include <ipc/ipc.h>
#include <ipc/services.h>
#include <ipc/net.h>
#include <ipc/arp.h>
#include <ipc/il.h>
#include <byteorder.h>
#include <err.h>

#include <net/modules.h>
#include <net/device.h>
#include <arp_interface.h>
#include <nil_interface.h>
#include <protocol_map.h>
#include <adt/measured_strings.h>
#include <net/packet.h>
#include <packet_client.h>
#include <packet_remote.h>
#include <il_interface.h>
#include <il_local.h>

#include "arp.h"
#include "arp_header.h"
#include "arp_oc.h"
#include "arp_module.h"


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

/** ARP global data.
 */
arp_globals_t   arp_globals;

/** Clears the device specific data.
 *  @param[in] device The device specific data.
 */
void arp_clear_device(arp_device_ref device);

/** Creates new protocol specific data.
 *  Allocates and returns the needed memory block as the proto parameter.
 *  @param[out] proto The allocated protocol specific data.
 *  @param[in] service The protocol module service.
 *  @param[in] address The actual protocol device address.
 *  @returns EOK on success.
 *  @returns ENOMEM if there is not enough memory left.
 */
int arp_proto_create(arp_proto_ref * proto, services_t service, measured_string_ref address);

/** @name Message processing functions
 */
/*@{*/

/** Registers the device.
 *  Creates new device entry in the cache or updates the protocol address if the device with the device identifier and the driver service exists.
 *  @param[in] device_id The device identifier.
 *  @param[in] service The device driver service.
 *  @param[in] protocol The protocol service.
 *  @param[in] address The actual device protocol address.
 *  @returns EOK on success.
 *  @returns EEXIST if another device with the same device identifier and different driver service exists.
 *  @returns ENOMEM if there is not enough memory left.
 *  @returns Other error codes as defined for the measured_strings_return() function.
 */
int arp_device_message(device_id_t device_id, services_t service, services_t protocol, measured_string_ref address);

/** 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 ENOENT if device is not found.
 *  @returns EOK on success.
 */
int arp_mtu_changed_message(device_id_t device_id, size_t mtu);

/** Processes the received ARP packet.
 *  Updates the source hardware address if the source entry exists or the packet is targeted to my protocol address.
 *  Responses to the ARP request if the packet is the ARP request and is targeted to my address.
 *  @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 1 on success and the packet has been reused.
 *  @returns EINVAL if the packet is too small to carry an ARP 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 arp_receive_message(device_id_t device_id, packet_t packet);

/** Returns the hardware address for the given protocol address.
 *  Sends the ARP request packet if the hardware address is not found in the cache.
 *  @param[in] device_id The device identifier.
 *  @param[in] protocol The protocol service.
 *  @param[in] target The target protocol address.
 *  @returns The hardware address of the target.
 *  @returns NULL if the target parameter is NULL.
 *  @returns NULL if the device is not found.
 *  @returns NULL if the device packet is too small to send a&nbsp;request.
 *  @returns NULL if the hardware address is not found in the cache.
 */
measured_string_ref arp_translate_message(device_id_t device_id, services_t protocol, measured_string_ref target);

/*@}*/

DEVICE_MAP_IMPLEMENT(arp_cache, arp_device_t)

INT_MAP_IMPLEMENT(arp_protos, arp_proto_t)

GENERIC_CHAR_MAP_IMPLEMENT(arp_addr, measured_string_t)

int arp_clean_cache_req(int arp_phone){
        int count;
        arp_device_ref device;

        fibril_rwlock_write_lock(&arp_globals.lock);
        for(count = arp_cache_count(&arp_globals.cache) - 1; count >= 0; -- count){
                device = arp_cache_get_index(&arp_globals.cache, count);
                if(device){
                        arp_clear_device(device);
                        if(device->addr_data){
                                free(device->addr_data);
                        }
                        if(device->broadcast_data){
                                free(device->broadcast_data);
                        }
                }
        }
        arp_cache_clear(&arp_globals.cache);
        fibril_rwlock_write_unlock(&arp_globals.lock);
        printf("Cache cleaned\n");
        return EOK;
}

int arp_clear_address_req(int arp_phone, device_id_t device_id, services_t protocol, measured_string_ref address){
        arp_device_ref device;
        arp_proto_ref proto;

        fibril_rwlock_write_lock(&arp_globals.lock);
        device = arp_cache_find(&arp_globals.cache, device_id);
        if(! device){
                fibril_rwlock_write_unlock(&arp_globals.lock);
                return ENOENT;
        }
        proto = arp_protos_find(&device->protos, protocol);
        if(! proto){
                fibril_rwlock_write_unlock(&arp_globals.lock);
                return ENOENT;
        }
        arp_addr_exclude(&proto->addresses, address->value, address->length);
        fibril_rwlock_write_unlock(&arp_globals.lock);
        return EOK;
}

void arp_clear_device(arp_device_ref device){
        int count;
        arp_proto_ref proto;

        for(count = arp_protos_count(&device->protos) - 1; count >= 0; -- count){
                proto = arp_protos_get_index(&device->protos, count);
                if(proto){
                        if(proto->addr){
                                free(proto->addr);
                        }
                        if(proto->addr_data){
                                free(proto->addr_data);
                        }
                        arp_addr_destroy(&proto->addresses);
                }
        }
        arp_protos_clear(&device->protos);
}

int arp_clear_device_req(int arp_phone, device_id_t device_id){
        arp_device_ref device;

        fibril_rwlock_write_lock(&arp_globals.lock);
        device = arp_cache_find(&arp_globals.cache, device_id);
        if(! device){
                fibril_rwlock_write_unlock(&arp_globals.lock);
                return ENOENT;
        }
        arp_clear_device(device);
        printf("Device %d cleared\n", device_id);
        fibril_rwlock_write_unlock(&arp_globals.lock);
        return EOK;
}

int arp_device_message(device_id_t device_id, services_t service, services_t protocol, measured_string_ref address){
        ERROR_DECLARE;

        arp_device_ref device;
        arp_proto_ref proto;
        int index;
        hw_type_t hardware;

        fibril_rwlock_write_lock(&arp_globals.lock);
        // an existing device?
        device = arp_cache_find(&arp_globals.cache, device_id);
        if(device){
                if(device->service != service){
                        printf("Device %d already exists\n", device->device_id);
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        return EEXIST;
                }
                proto = arp_protos_find(&device->protos, protocol);
                if(proto){
                        free(proto->addr);
                        free(proto->addr_data);
                        proto->addr = address;
                        proto->addr_data = address->value;
                }else{
                        if(ERROR_OCCURRED(arp_proto_create(&proto, protocol, address))){
                                fibril_rwlock_write_unlock(&arp_globals.lock);
                                return ERROR_CODE;
                        }
                        index = arp_protos_add(&device->protos, proto->service, proto);
                        if(index < 0){
                                fibril_rwlock_write_unlock(&arp_globals.lock);
                                free(proto);
                                return index;
                        }
                        printf("New protocol added:\n\tdevice id\t= %d\n\tproto\t= %d", device_id, protocol);
                }
        }else{
                hardware = hardware_map(service);
                if(! hardware){
                        return ENOENT;
                }
                // create a new device
                device = (arp_device_ref) malloc(sizeof(arp_device_t));
                if(! device){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        return ENOMEM;
                }
                device->hardware = hardware;
                device->device_id = device_id;
                if(ERROR_OCCURRED(arp_protos_initialize(&device->protos))
                        || ERROR_OCCURRED(arp_proto_create(&proto, protocol, address))){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        free(device);
                        return ERROR_CODE;
                }
                index = arp_protos_add(&device->protos, proto->service, proto);
                if(index < 0){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        arp_protos_destroy(&device->protos);
                        free(device);
                        return index;
                }
                device->service = service;
                // bind the new one
                device->phone = nil_bind_service(device->service, (ipcarg_t) device->device_id, SERVICE_ARP, arp_globals.client_connection);
                if(device->phone < 0){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        arp_protos_destroy(&device->protos);
                        free(device);
                        return EREFUSED;
                }
                // get packet dimensions
                if(ERROR_OCCURRED(nil_packet_size_req(device->phone, device_id, &device->packet_dimension))){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        arp_protos_destroy(&device->protos);
                        free(device);
                        return ERROR_CODE;
                }
                // get hardware address
                if(ERROR_OCCURRED(nil_get_addr_req(device->phone, device_id, &device->addr, &device->addr_data))){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        arp_protos_destroy(&device->protos);
                        free(device);
                        return ERROR_CODE;
                }
                // get broadcast address
                if(ERROR_OCCURRED(nil_get_broadcast_addr_req(device->phone, device_id, &device->broadcast_addr, &device->broadcast_data))){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        free(device->addr);
                        free(device->addr_data);
                        arp_protos_destroy(&device->protos);
                        free(device);
                        return ERROR_CODE;
                }
                if(ERROR_OCCURRED(arp_cache_add(&arp_globals.cache, device->device_id, device))){
                        fibril_rwlock_write_unlock(&arp_globals.lock);
                        free(device->addr);
                        free(device->addr_data);
                        free(device->broadcast_addr);
                        free(device->broadcast_data);
                        arp_protos_destroy(&device->protos);
                        free(device);
                        return ERROR_CODE;
                }
                printf("%s: Device registered (id: %d, type: 0x%x, service: %d, proto: %d)\n",
                    NAME, device->device_id, device->hardware, device->service, protocol);
        }
        fibril_rwlock_write_unlock(&arp_globals.lock);
        return EOK;
}

int arp_device_req(int arp_phone, device_id_t device_id, services_t protocol, services_t netif, measured_string_ref address){
        ERROR_DECLARE;

        measured_string_ref tmp;

        // copy the given address for exclusive use
        tmp = measured_string_copy(address);
        if(ERROR_OCCURRED(arp_device_message(device_id, netif, protocol, tmp))){
                free(tmp->value);
                free(tmp);
        }
        return ERROR_CODE;
}

int arp_initialize(async_client_conn_t client_connection){
        ERROR_DECLARE;

        fibril_rwlock_initialize(&arp_globals.lock);
        fibril_rwlock_write_lock(&arp_globals.lock);
        arp_globals.client_connection = client_connection;
        ERROR_PROPAGATE(arp_cache_initialize(&arp_globals.cache));
        fibril_rwlock_write_unlock(&arp_globals.lock);
        return EOK;
}

int arp_message_standalone(ipc_callid_t callid, ipc_call_t *call,
    ipc_call_t *answer, int *answer_count)
{
        ERROR_DECLARE;
        
        measured_string_ref address;
        measured_string_ref translation;
        char * data;
        packet_t packet;
        packet_t next;
        
        *answer_count = 0;
        switch (IPC_GET_METHOD(*call)) {
                case IPC_M_PHONE_HUNGUP:
                        return EOK;
                case NET_ARP_DEVICE:
                        ERROR_PROPAGATE(measured_strings_receive(&address, &data, 1));
                        if(ERROR_OCCURRED(arp_device_message(IPC_GET_DEVICE(call), IPC_GET_SERVICE(call), ARP_GET_NETIF(call), address))){
                                free(address);
                                free(data);
                        }
                        return ERROR_CODE;
                case NET_ARP_TRANSLATE:
                        ERROR_PROPAGATE(measured_strings_receive(&address, &data, 1));
                        fibril_rwlock_read_lock(&arp_globals.lock);
                        translation = arp_translate_message(IPC_GET_DEVICE(call), IPC_GET_SERVICE(call), address);
                        free(address);
                        free(data);
                        if(! translation){
                                fibril_rwlock_read_unlock(&arp_globals.lock);
                                return ENOENT;
                        }
                        ERROR_CODE = measured_strings_reply(translation, 1);
                        fibril_rwlock_read_unlock(&arp_globals.lock);
                        return ERROR_CODE;
                case NET_ARP_CLEAR_DEVICE:
                        return arp_clear_device_req(0, IPC_GET_DEVICE(call));
                case NET_ARP_CLEAR_ADDRESS:
                        ERROR_PROPAGATE(measured_strings_receive(&address, &data, 1));
                        arp_clear_address_req(0, IPC_GET_DEVICE(call), IPC_GET_SERVICE(call), address);
                        free(address);
                        free(data);
                        return EOK;
                case NET_ARP_CLEAN_CACHE:
                        return arp_clean_cache_req(0);
                case NET_IL_DEVICE_STATE:
                        // do nothing - keep the cache
                        return EOK;
                case NET_IL_RECEIVED:
                        if(! ERROR_OCCURRED(packet_translate_remote(arp_globals.net_phone, &packet, IPC_GET_PACKET(call)))){
                                fibril_rwlock_read_lock(&arp_globals.lock);
                                do{
                                        next = pq_detach(packet);
                                        ERROR_CODE = arp_receive_message(IPC_GET_DEVICE(call), packet);
                                        if(ERROR_CODE != 1){
                                                pq_release_remote(arp_globals.net_phone, packet_get_id(packet));
                                        }
                                        packet = next;
                                }while(packet);
                                fibril_rwlock_read_unlock(&arp_globals.lock);
                        }
                        return ERROR_CODE;
                case NET_IL_MTU_CHANGED:
                        return arp_mtu_changed_message(IPC_GET_DEVICE(call), IPC_GET_MTU(call));
        }
        
        return ENOTSUP;
}

int arp_mtu_changed_message(device_id_t device_id, size_t mtu){
        arp_device_ref device;

        fibril_rwlock_write_lock(&arp_globals.lock);
        device = arp_cache_find(&arp_globals.cache, device_id);
        if(! device){
                fibril_rwlock_write_unlock(&arp_globals.lock);
                return ENOENT;
        }
        device->packet_dimension.content = mtu;
        printf("arp - device %d changed mtu to %d\n\n", device_id, mtu);
        fibril_rwlock_write_unlock(&arp_globals.lock);
        return EOK;
}

int arp_proto_create(arp_proto_ref * proto, services_t service, measured_string_ref address){
        ERROR_DECLARE;

        *proto = (arp_proto_ref) malloc(sizeof(arp_proto_t));
        if(!(*proto)){
                return ENOMEM;
        }
        (** proto).service = service;
        (** proto).addr = address;
        (** proto).addr_data = address->value;
        if(ERROR_OCCURRED(arp_addr_initialize(&(** proto).addresses))){
                free(*proto);
                return ERROR_CODE;
        }
        return EOK;
}

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

        size_t length;
        arp_header_ref header;
        arp_device_ref device;
        arp_proto_ref proto;
        measured_string_ref hw_source;
        uint8_t * src_hw;
        uint8_t * src_proto;
        uint8_t * des_hw;
        uint8_t * des_proto;

        length = packet_get_data_length(packet);
        if(length <= sizeof(arp_header_t)){
                return EINVAL;
        }
        device = arp_cache_find(&arp_globals.cache, device_id);
        if(! device){
                return ENOENT;
        }
        header = (arp_header_ref) packet_get_data(packet);
        if((ntohs(header->hardware) != device->hardware)
                || (length < sizeof(arp_header_t) + header->hardware_length * 2u + header->protocol_length * 2u)){
                return EINVAL;
        }
        proto = arp_protos_find(&device->protos, protocol_unmap(device->service, ntohs(header->protocol)));
        if(! proto){
                return ENOENT;
        }
        src_hw = ((uint8_t *) header) + sizeof(arp_header_t);
        src_proto = src_hw + header->hardware_length;
        des_hw = src_proto + header->protocol_length;
        des_proto = des_hw + header->hardware_length;
        hw_source = arp_addr_find(&proto->addresses, (char *) src_proto, CONVERT_SIZE(uint8_t, char, header->protocol_length));
        // exists?
        if(hw_source){
                if(hw_source->length != CONVERT_SIZE(uint8_t, char, header->hardware_length)){
                        return EINVAL;
                }
                memcpy(hw_source->value, src_hw, hw_source->length);
        }
        // is my protocol address?
        if(proto->addr->length != CONVERT_SIZE(uint8_t, char, header->protocol_length)){
                return EINVAL;
        }
        if(! str_lcmp(proto->addr->value, (char *) des_proto, proto->addr->length)){
                // not already upadted?
                if(! hw_source){
                        hw_source = measured_string_create_bulk((char *) src_hw, CONVERT_SIZE(uint8_t, char, header->hardware_length));
                        if(! hw_source){
                                return ENOMEM;
                        }
                        ERROR_PROPAGATE(arp_addr_add(&proto->addresses, (char *) src_proto, CONVERT_SIZE(uint8_t, char, header->protocol_length), hw_source));
                }
                if(ntohs(header->operation) == ARPOP_REQUEST){
                        header->operation = htons(ARPOP_REPLY);
                        memcpy(des_proto, src_proto, header->protocol_length);
                        memcpy(src_proto, proto->addr->value, header->protocol_length);
                        memcpy(src_hw, device->addr->value, device->packet_dimension.addr_len);
                        memcpy(des_hw, hw_source->value, header->hardware_length);
                        ERROR_PROPAGATE(packet_set_addr(packet, src_hw, des_hw, header->hardware_length));
                        nil_send_msg(device->phone, device_id, packet, SERVICE_ARP);
                        return 1;
                }
        }
        return EOK;
}

task_id_t arp_task_get_id(void){
        return task_get_id();
}

measured_string_ref arp_translate_message(device_id_t device_id, services_t protocol, measured_string_ref target){
        arp_device_ref device;
        arp_proto_ref proto;
        measured_string_ref addr;
        size_t length;
        packet_t packet;
        arp_header_ref header;

        if(! target){
                return NULL;
        }
        device = arp_cache_find(&arp_globals.cache, device_id);
        if(! device){
                return NULL;
        }
        proto = arp_protos_find(&device->protos, protocol);
        if((! proto) || (proto->addr->length != target->length)){
                return NULL;
        }
        addr = arp_addr_find(&proto->addresses, target->value, target->length);
        if(addr){
                return addr;
        }
        // ARP packet content size = header + (address + translation) * 2
        length = 8 + (CONVERT_SIZE(char, uint8_t, proto->addr->length) + CONVERT_SIZE(char, uint8_t, device->addr->length)) * 2;
        if(length > device->packet_dimension.content){
                return NULL;
        }
        packet = packet_get_4_remote(arp_globals.net_phone, device->packet_dimension.addr_len, device->packet_dimension.prefix, length, device->packet_dimension.suffix);
        if(! packet){
                return NULL;
        }
        header = (arp_header_ref) packet_suffix(packet, length);
        if(! header){
                pq_release_remote(arp_globals.net_phone, packet_get_id(packet));
                return NULL;
        }
        header->hardware = htons(device->hardware);
        header->hardware_length = (uint8_t) device->addr->length;
        header->protocol = htons(protocol_map(device->service, protocol));
        header->protocol_length = (uint8_t) proto->addr->length;
        header->operation = htons(ARPOP_REQUEST);
        length = sizeof(arp_header_t);
        memcpy(((uint8_t *) header) + length, device->addr->value, device->addr->length);
        length += device->addr->length;
        memcpy(((uint8_t *) header) + length, proto->addr->value, proto->addr->length);
        length += proto->addr->length;
        bzero(((uint8_t *) header) + length, device->addr->length);
        length += device->addr->length;
        memcpy(((uint8_t *) header) + length, target->value, target->length);
        if(packet_set_addr(packet, (uint8_t *) device->addr->value, (uint8_t *) device->broadcast_addr->value, CONVERT_SIZE(char, uint8_t, device->addr->length)) != EOK){
                pq_release_remote(arp_globals.net_phone, packet_get_id(packet));
                return NULL;
        }
        nil_send_msg(device->phone, device_id, packet, SERVICE_ARP);
        return NULL;
}

/** Default thread for new connections.
 *
 *  @param[in] iid The initial message identifier.
 *  @param[in] icall The initial message call structure.
 *
 */
static void il_client_connection(ipc_callid_t iid, ipc_call_t * icall)
{
        /*
         * Accept the connection
         *  - Answer the first IPC_M_CONNECT_ME_TO call.
         */
        ipc_answer_0(iid, EOK);
        
        while(true) {
                ipc_call_t answer;
                int answer_count;
                
                /* Clear the answer structure */
                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 = il_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.
 *
 */
int main(int argc, char *argv[])
{
        ERROR_DECLARE;
        
        /* Start the module */
        if (ERROR_OCCURRED(il_module_start_standalone(il_client_connection)))
                return ERROR_CODE;
        
        return EOK;
}

/** @}
 */