source: mainline/uspace/lib/net/tl/socket_core.c@ c6533a7

/*
 * 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 libnet
 * @{
 */

/** @file
 * Socket common core implementation.
 */

#include <socket_core.h>
#include <net/socket_codes.h>
#include <net/in.h>
#include <net/inet.h>
#include <net/modules.h>
#include <stdint.h>
#include <stdlib.h>
#include <errno.h>
#include <adt/dynamic_fifo.h>
#include <adt/int_map.h>

/**
 * Maximum number of random attempts to find a new socket identifier before
 * switching to the sequence.
 */
#define SOCKET_ID_TRIES  100

/** Bound port sockets.*/
struct socket_port {
        /** The bound sockets map. */
        socket_port_map_t map;
        /** The bound sockets count. */
        int count;
};

INT_MAP_IMPLEMENT(socket_cores, socket_core_t);

GENERIC_CHAR_MAP_IMPLEMENT(socket_port_map, socket_core_t *);

INT_MAP_IMPLEMENT(socket_ports, socket_port_t);

/** Destroy the socket.
 *
 * If the socket is bound, the port is released.
 * Release all buffered packets, call the release function and remove the
 * socket from the local sockets.
 *
 * @param[in]     sess           Packet server session.
 * @param[in]     socket         Socket to be destroyed.
 * @param[in,out] local_sockets  Local sockets to be updated.
 * @param[in,out] global_sockets Global sockets to be updated.
 * @param[in]     socket_release Client release callback function.
 *
 */
static void socket_destroy_core(async_sess_t *sess, socket_core_t *socket,
    socket_cores_t *local_sockets, socket_ports_t *global_sockets,
    void (* socket_release)(socket_core_t *socket))
{
        /* If bound */
        if (socket->port) {
                /* Release the port */
                socket_port_release(global_sockets, socket);
        }
        
        dyn_fifo_destroy(&socket->accepted);
        
        if (socket_release)
                socket_release(socket);
        
        socket_cores_exclude(local_sockets, socket->socket_id, free);
}

/** Destroy local sockets.
 *
 * Release all buffered packets and call the release function for each of the
 * sockets.
 *
 * @param[in]     sess           Packet server session.
 * @param[in]     local_sockets  Local sockets to be destroyed.
 * @param[in,out] global_sockets Global sockets to be updated.
 * @param[in]     socket_release Client release callback function.
 *
 */
void socket_cores_release(async_sess_t *sess, socket_cores_t *local_sockets,
    socket_ports_t *global_sockets,
    void (* socket_release)(socket_core_t *socket))
{
        if (!socket_cores_is_valid(local_sockets))
                return;
        
        local_sockets->magic = 0;
        
        int index;
        for (index = 0; index < local_sockets->next; ++index) {
                if (socket_cores_item_is_valid(&local_sockets->items[index])) {
                        local_sockets->items[index].magic = 0;
                        
                        if (local_sockets->items[index].value) {
                                socket_destroy_core(sess,
                                    local_sockets->items[index].value,
                                    local_sockets, global_sockets,
                                    socket_release);
                                free(local_sockets->items[index].value);
                                local_sockets->items[index].value = NULL;
                        }
                }
        }
        
        free(local_sockets->items);
}

/** Adds the socket to a socket port.
 *
 * @param[in,out] socket_port The socket port structure.
 * @param[in] socket    The socket to be added.
 * @param[in] key       The socket key identifier.
 * @param[in] key_length The socket key length.
 * @return              EOK on success.
 * @return              ENOMEM if there is not enough memory left.
 */
static int
socket_port_add_core(socket_port_t *socket_port, socket_core_t *socket,
    const uint8_t *key, size_t key_length)
{
        socket_core_t **socket_ref;
        int rc;

        /* Create a wrapper */
        socket_ref = malloc(sizeof(*socket_ref));
        if (!socket_ref)
                return ENOMEM;

        *socket_ref = socket;
        /* Add the wrapper */
        rc = socket_port_map_add(&socket_port->map, key, key_length,
            socket_ref);
        if (rc != EOK) {
                free(socket_ref);
                return rc;
        }
        
        ++socket_port->count;
        socket->key = key;
        socket->key_length = key_length;
        
        return EOK;
}

/** Binds the socket to the port.
 *
 * The SOCKET_MAP_KEY_LISTENING key identifier is used.
 *
 * @param[in] global_sockets The global sockets to be updated.
 * @param[in] socket    The socket to be added.
 * @param[in] port      The port number to be bound to.
 * @return              EOK on success.
 * @return              ENOMEM if there is not enough memory left.
 * @return              Other error codes as defined for the
 *                       socket_ports_add() function.
 */
static int
socket_bind_insert(socket_ports_t *global_sockets, socket_core_t *socket,
    int port)
{
        socket_port_t *socket_port;
        int rc;

        /* Create a wrapper */
        socket_port = malloc(sizeof(*socket_port));
        if (!socket_port)
                return ENOMEM;

        socket_port->count = 0;
        rc = socket_port_map_initialize(&socket_port->map);
        if (rc != EOK)
                goto fail;
        
        rc = socket_port_add_core(socket_port, socket,
            (const uint8_t *) SOCKET_MAP_KEY_LISTENING, 0);
        if (rc != EOK)
                goto fail;
        
        /* Register the incoming port */
        rc = socket_ports_add(global_sockets, port, socket_port);
        if (rc < 0)
                goto fail;
        
        socket->port = port;
        return EOK;

fail:
        socket_port_map_destroy(&socket_port->map, free);
        free(socket_port);
        return rc;
        
}

/** Binds the socket to the port.
 *
 * The address port is used if set, a free port is used if not.
 *
 * @param[in] local_sockets The local sockets to be searched.
 * @param[in,out] global_sockets The global sockets to be updated.
 * @param[in] socket_id The new socket identifier.
 * @param[in] addr      The address to be bound to.
 * @param[in] addrlen   The address length.
 * @param[in] free_ports_start The minimum free port.
 * @param[in] free_ports_end The maximum free port.
 * @param[in] last_used_port The last used free port.
 * @return              EOK on success.
 * @return              ENOTSOCK if the socket was not found.
 * @return              EAFNOSUPPORT if the address family is not supported.
 * @return              EADDRINUSE if the port is already in use.
 * @return              Other error codes as defined for the
 *                      socket_bind_free_port() function.
 * @return              Other error codes as defined for the
 *                      socket_bind_insert() function.
 */
int
socket_bind(socket_cores_t *local_sockets, socket_ports_t *global_sockets,
    int socket_id, void *addr, size_t addrlen, int free_ports_start,
    int free_ports_end, int last_used_port)
{
        socket_core_t *socket;
        socket_port_t *socket_port;
        struct sockaddr *address;
        struct sockaddr_in *address_in;

        if (addrlen < sizeof(struct sockaddr))
                return EINVAL;

        address = (struct sockaddr *) addr;
        switch (address->sa_family) {
        case AF_INET:
                if (addrlen != sizeof(struct sockaddr_in))
                        return EINVAL;
                
                address_in = (struct sockaddr_in *) addr;
                /* Find the socket */
                socket = socket_cores_find(local_sockets, socket_id);
                if (!socket)
                        return ENOTSOCK;
                
                /* Bind a free port? */
                if (address_in->sin_port <= 0)
                        return socket_bind_free_port(global_sockets, socket,
                             free_ports_start, free_ports_end, last_used_port);
                
                /* Try to find the port */
                socket_port = socket_ports_find(global_sockets,
                    ntohs(address_in->sin_port));
                if (socket_port) {
                        /* Already used */
                        return EADDRINUSE;
                }
                
                /* If bound */
                if (socket->port) {
                        /* Release the port */
                        socket_port_release(global_sockets, socket);
                }
                socket->port = -1;
                
                return socket_bind_insert(global_sockets, socket,
                    ntohs(address_in->sin_port));
                
        case AF_INET6:
                // TODO IPv6
                break;
        }
        
        return EAFNOSUPPORT;
}

/** Binds the socket to a free port.
 *
 * The first free port is used.
 *
 * @param[in,out] global_sockets The global sockets to be updated.
 * @param[in,out] socket The socket to be bound.
 * @param[in] free_ports_start The minimum free port.
 * @param[in] free_ports_end The maximum free port.
 * @param[in] last_used_port The last used free port.
 * @return              EOK on success.
 * @return              ENOTCONN if no free port was found.
 * @return              Other error codes as defined for the
 *                      socket_bind_insert() function.
 */
int
socket_bind_free_port(socket_ports_t *global_sockets, socket_core_t *socket,
    int free_ports_start, int free_ports_end, int last_used_port)
{
        int index;

        /* From the last used one */
        index = last_used_port;
        
        do {
                ++index;
                
                /* Till the range end */
                if (index >= free_ports_end) {
                        /* Start from the range beginning */
                        index = free_ports_start - 1;
                        do {
                                ++index;
                                /* Till the last used one */
                                if (index >= last_used_port) {
                                        /* None found */
                                        return ENOTCONN;
                                }
                        } while (socket_ports_find(global_sockets, index));
                        
                        /* Found, break immediately */
                        break;
                }
                
        } while (socket_ports_find(global_sockets, index));
        
        return socket_bind_insert(global_sockets, socket, index);
}

/** Tries to find a new free socket identifier.
 *
 * @param[in] local_sockets The local sockets to be searched.
 * @param[in] positive  A value indicating whether a positive identifier is
 *                      requested. A negative identifier is requested if set to
 *                      false.
 * @return              The new socket identifier.
 * @return              ELIMIT if there is no socket identifier available.
 */
static int socket_generate_new_id(socket_cores_t *local_sockets, int positive)
{
        int socket_id;
        int count;

        count = 0;
#if 0
        socket_id = socket_globals.last_id;
#endif
        do {
                if (count < SOCKET_ID_TRIES) {
                        socket_id = rand() % INT_MAX;
                        ++count;
                } else if (count == SOCKET_ID_TRIES) {
                        socket_id = 1;
                        ++count;
                /* Only this branch for last_id */
                } else {
                        if (socket_id < INT_MAX) {
                                ++ socket_id;
#if 0
                        } else if(socket_globals.last_id) {
                                socket_globals.last_id = 0;
                                socket_id = 1;
#endif
                        } else {
                                return ELIMIT;
                        }
                }
        } while (socket_cores_find(local_sockets,
            ((positive ? 1 : -1) * socket_id)));
        
//      last_id = socket_id
        return socket_id;
}

/** Create a new socket.
 *
 * @param[in,out] local_sockets Local sockets to be updated.
 * @param[in]     sess          Application session.
 * @param[in]     specific_data Socket specific data.
 * @param[in,out] socket_id     New socket identifier. A new identifier
 *                              is chosen if set to zero or negative.
 *                              A negative identifier is chosen if set
 *                              to negative.
 *
 * @return EOK on success.
 * @return EINVAL if the socket_id parameter is NULL.
 * @return ENOMEM if there is not enough memory left.
 *
 */
int socket_create(socket_cores_t *local_sockets, async_sess_t* sess,
    void *specific_data, int *socket_id)
{
        socket_core_t *socket;
        int positive;
        int rc;

        if (!socket_id)
                return EINVAL;
        
        /* Store the socket */
        if (*socket_id <= 0) {
                positive = (*socket_id == 0);
                *socket_id = socket_generate_new_id(local_sockets, positive);
                if (*socket_id <= 0)
                        return *socket_id;
                if (!positive)
                        *socket_id *= -1;
        } else if(socket_cores_find(local_sockets, *socket_id)) {
                return EEXIST;
        }
        
        socket = (socket_core_t *) malloc(sizeof(*socket));
        if (!socket)
                return ENOMEM;
        
        /* Initialize */
        socket->sess = sess;
        socket->port = -1;
        socket->key = NULL;
        socket->key_length = 0;
        socket->specific_data = specific_data;
        
        rc = dyn_fifo_initialize(&socket->accepted, SOCKET_INITIAL_ACCEPTED_SIZE);
        if (rc != EOK) {
                free(socket);
                return rc;
        }
        socket->socket_id = *socket_id;
        rc = socket_cores_add(local_sockets, socket->socket_id, socket);
        if (rc < 0) {
                dyn_fifo_destroy(&socket->accepted);
                free(socket);
                return rc;
        }
        
        return EOK;
}

/** Destroy the socket.
 *
 * If the socket is bound, the port is released.
 * Release all buffered packets, call the release function and remove the
 * socket from the local sockets.
 *
 * @param[in]     sess           Packet server session.
 * @param[in]     socket_id      Socket identifier.
 * @param[in,out] local_sockets  Local sockets to be updated.
 * @param[in,out] global_sockets Global sockets to be updated.
 * @param[in]     socket_release Client release callback function.
 *
 * @return EOK on success.
 * @return ENOTSOCK if the socket is not found.
 *
 */
int
socket_destroy(async_sess_t *sess, int socket_id, socket_cores_t *local_sockets,
    socket_ports_t *global_sockets,
    void (*socket_release)(socket_core_t *socket))
{
        /* Find the socket */
        socket_core_t *socket = socket_cores_find(local_sockets, socket_id);
        if (!socket)
                return ENOTSOCK;
        
        /* Destroy all accepted sockets */
        int accepted_id;
        while ((accepted_id = dyn_fifo_pop(&socket->accepted)) >= 0)
                socket_destroy(sess, accepted_id, local_sockets,
                    global_sockets, socket_release);
        
        socket_destroy_core(sess, socket, local_sockets, global_sockets,
            socket_release);
        
        return EOK;
}

/** Finds the bound port socket.
 *
 * @param[in] global_sockets The global sockets to be searched.
 * @param[in] port      The port number.
 * @param[in] key       The socket key identifier.
 * @param[in] key_length The socket key length.
 * @return              The found socket.
 * @return              NULL if no socket was found.
 */
socket_core_t *
socket_port_find(socket_ports_t *global_sockets, int port, const uint8_t *key,
    size_t key_length)
{
        socket_port_t *socket_port;
        socket_core_t **socket_ref;

        socket_port = socket_ports_find(global_sockets, port);
        if (socket_port && (socket_port->count > 0)) {
                socket_ref = socket_port_map_find(&socket_port->map, key,
                    key_length);
                if (socket_ref)
                        return *socket_ref;
        }
        
        return NULL;
}

/** Releases the socket port.
 *
 * If the socket is bound the port entry is released.
 * If there are no more port entries the port is release.
 *
 * @param[in] global_sockets The global sockets to be updated.
 * @param[in] socket    The socket to be unbound.
 */
void
socket_port_release(socket_ports_t *global_sockets, socket_core_t *socket)
{
        socket_port_t *socket_port;
        socket_core_t **socket_ref;

        if (!socket->port)
                return;
        
        /* Find ports */
        socket_port = socket_ports_find(global_sockets, socket->port);
        if (socket_port) {
                /* Find the socket */
                socket_ref = socket_port_map_find(&socket_port->map,
                    socket->key, socket->key_length);
                
                if (socket_ref) {
                        --socket_port->count;
                        
                        /* Release if empty */
                        if (socket_port->count <= 0) {
                                /* Destroy the map */
                                socket_port_map_destroy(&socket_port->map, free);
                                /* Release the port */
                                socket_ports_exclude(global_sockets,
                                    socket->port, free);
                        } else {
                                /* Remove */
                                socket_port_map_exclude(&socket_port->map,
                                    socket->key, socket->key_length, free);
                        }
                }
        }
        
        socket->port = 0;
        socket->key = NULL;
        socket->key_length = 0;
}

/** Adds the socket to an already bound port.
 *
 * @param[in] global_sockets The global sockets to be updated.
 * @param[in] port      The port number to be bound to.
 * @param[in] socket    The socket to be added.
 * @param[in] key       The socket key identifier.
 * @param[in] key_length The socket key length.
 * @return              EOK on success.
 * @return              ENOENT if the port is not already used.
 * @return              Other error codes as defined for the
 *                      socket_port_add_core() function.
 */
int
socket_port_add(socket_ports_t *global_sockets, int port,
    socket_core_t *socket, const uint8_t *key, size_t key_length)
{
        socket_port_t *socket_port;
        int rc;

        /* Find ports */
        socket_port = socket_ports_find(global_sockets, port);
        if (!socket_port)
                return ENOENT;
        
        /* Add the socket */
        rc = socket_port_add_core(socket_port, socket, key, key_length);
        if (rc != EOK)
                return rc;
        
        socket->port = port;
        return EOK;
}

/** @}
 */