source: mainline/uspace/srv/net/loopip/loopip.c@ ca48672

/*
 * Copyright (c) 2025 Jiri Svoboda
 * 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 loopip
 * @{
 */
/**
 * @file
 * @brief Loopback IP link provider
 */

#include <adt/prodcons.h>
#include <async.h>
#include <errno.h>
#include <str_error.h>
#include <inet/iplink_srv.h>
#include <inet/addr.h>
#include <inet/eth_addr.h>
#include <io/log.h>
#include <loc.h>
#include <stdio.h>
#include <stdlib.h>
#include <str.h>
#include <task.h>

#define NAME  "loopip"

static errno_t loopip_open(iplink_srv_t *srv);
static errno_t loopip_close(iplink_srv_t *srv);
static errno_t loopip_send(iplink_srv_t *srv, iplink_sdu_t *sdu);
static errno_t loopip_send6(iplink_srv_t *srv, iplink_sdu6_t *sdu);
static errno_t loopip_get_mtu(iplink_srv_t *srv, size_t *mtu);
static errno_t loopip_get_mac48(iplink_srv_t *srv, eth_addr_t *mac);
static errno_t loopip_addr_add(iplink_srv_t *srv, inet_addr_t *addr);
static errno_t loopip_addr_remove(iplink_srv_t *srv, inet_addr_t *addr);

static void loopip_client_conn(ipc_call_t *icall, void *arg);

static iplink_ops_t loopip_iplink_ops = {
        .open = loopip_open,
        .close = loopip_close,
        .send = loopip_send,
        .send6 = loopip_send6,
        .get_mtu = loopip_get_mtu,
        .get_mac48 = loopip_get_mac48,
        .addr_add = loopip_addr_add,
        .addr_remove = loopip_addr_remove
};

static iplink_srv_t loopip_iplink;
static prodcons_t loopip_rcv_queue;

typedef struct {
        link_t link;

        /* XXX Version should be part of SDU */
        ip_ver_t ver;
        iplink_recv_sdu_t sdu;
} rqueue_entry_t;

static errno_t loopip_recv_fibril(void *arg)
{
        while (true) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_recv_fibril(): Wait for one item");
                link_t *link = prodcons_consume(&loopip_rcv_queue);
                rqueue_entry_t *rqe =
                    list_get_instance(link, rqueue_entry_t, link);

                (void) iplink_ev_recv(&loopip_iplink, &rqe->sdu, rqe->ver);

                free(rqe->sdu.data);
                free(rqe);
        }

        return 0;
}

static errno_t loopip_init(void)
{
        loc_srv_t *srv;

        async_set_fallback_port_handler(loopip_client_conn, NULL);

        errno_t rc = loc_server_register(NAME, &srv);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed registering server.");
                return rc;
        }

        iplink_srv_init(&loopip_iplink);
        loopip_iplink.ops = &loopip_iplink_ops;
        loopip_iplink.arg = NULL;

        prodcons_initialize(&loopip_rcv_queue);

        const char *svc_name = "net/loopback";
        service_id_t sid;
        rc = loc_service_register(srv, svc_name, fallback_port_id, &sid);
        if (rc != EOK) {
                loc_server_unregister(srv);
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed registering service %s.",
                    svc_name);
                return rc;
        }

        category_id_t iplink_cat;
        rc = loc_category_get_id("iplink", &iplink_cat, IPC_FLAG_BLOCKING);
        if (rc != EOK) {
                loc_service_unregister(srv, sid);
                loc_server_unregister(srv);
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed resolving category 'iplink'.");
                return rc;
        }

        rc = loc_service_add_to_cat(srv, sid, iplink_cat);
        if (rc != EOK) {
                loc_service_unregister(srv, sid);
                loc_server_unregister(srv);
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed adding %s to category.",
                    svc_name);
                return rc;
        }

        fid_t fid = fibril_create(loopip_recv_fibril, NULL);
        if (fid == 0) {
                loc_service_unregister(srv, sid);
                loc_server_unregister(srv);
                return ENOMEM;
        }

        fibril_add_ready(fid);

        return EOK;
}

static void loopip_client_conn(ipc_call_t *icall, void *arg)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_client_conn()");
        iplink_conn(icall, &loopip_iplink);
}

static errno_t loopip_open(iplink_srv_t *srv)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_open()");
        return EOK;
}

static errno_t loopip_close(iplink_srv_t *srv)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_close()");
        return EOK;
}

static errno_t loopip_send(iplink_srv_t *srv, iplink_sdu_t *sdu)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_send()");

        rqueue_entry_t *rqe = calloc(1, sizeof(rqueue_entry_t));
        if (rqe == NULL)
                return ENOMEM;

        /*
         * Clone SDU
         */
        rqe->ver = ip_v4;
        rqe->sdu.data = malloc(sdu->size);
        if (rqe->sdu.data == NULL) {
                free(rqe);
                return ENOMEM;
        }

        memcpy(rqe->sdu.data, sdu->data, sdu->size);
        rqe->sdu.size = sdu->size;

        /*
         * Insert to receive queue
         */
        prodcons_produce(&loopip_rcv_queue, &rqe->link);

        return EOK;
}

static errno_t loopip_send6(iplink_srv_t *srv, iplink_sdu6_t *sdu)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip6_send()");

        rqueue_entry_t *rqe = calloc(1, sizeof(rqueue_entry_t));
        if (rqe == NULL)
                return ENOMEM;

        /*
         * Clone SDU
         */
        rqe->ver = ip_v6;
        rqe->sdu.data = malloc(sdu->size);
        if (rqe->sdu.data == NULL) {
                free(rqe);
                return ENOMEM;
        }

        memcpy(rqe->sdu.data, sdu->data, sdu->size);
        rqe->sdu.size = sdu->size;

        /*
         * Insert to receive queue
         */
        prodcons_produce(&loopip_rcv_queue, &rqe->link);

        return EOK;
}

static errno_t loopip_get_mtu(iplink_srv_t *srv, size_t *mtu)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_get_mtu()");
        *mtu = 1500;
        return EOK;
}

static errno_t loopip_get_mac48(iplink_srv_t *src, eth_addr_t *mac)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "loopip_get_mac48()");
        return ENOTSUP;
}

static errno_t loopip_addr_add(iplink_srv_t *srv, inet_addr_t *addr)
{
        return EOK;
}

static errno_t loopip_addr_remove(iplink_srv_t *srv, inet_addr_t *addr)
{
        return EOK;
}

int main(int argc, char *argv[])
{
        printf("%s: HelenOS loopback IP link provider\n", NAME);

        errno_t rc = log_init(NAME);
        if (rc != EOK) {
                printf("%s: Failed to initialize logging: %s.\n", NAME, str_error(rc));
                return rc;
        }

        rc = loopip_init();
        if (rc != EOK) {
                printf("%s: Failed to initialize loopip: %s.\n", NAME, str_error(rc));
                return rc;
        }

        printf("%s: Accepting connections.\n", NAME);
        task_retval(0);
        async_manager();

        /* Not reached */
        return 0;
}

/** @}
 */