source: mainline/uspace/lib/net/tl/socket_core.c@ 854bfa5

/*
 * 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 <packet_client.h>
#include <packet_remote.h>

#include <net/socket_codes.h>
#include <net/in.h>
#include <net/inet.h>
#include <net/packet.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_ref);

INT_MAP_IMPLEMENT(socket_ports, socket_port_t);

/** Destroys the socket.
 *
 * If the socket is bound, the port is released.
 * Releases all buffered packets, calls the release function and removes the
 * socket from the local sockets.
 *
 * @param[in] packet_phone The packet server phone to release buffered packets.
 * @param[in] socket    The socket to be destroyed.
 * @param[in,out] local_sockets The local sockets to be updated.
 * @param[in,out] global_sockets The global sockets to be updated.
 * @param[in] socket_release The client release callback function.
 */
static void
socket_destroy_core(int packet_phone, socket_core_ref socket,
    socket_cores_ref local_sockets, socket_ports_ref global_sockets,
    void (* socket_release)(socket_core_ref socket))
{
        int packet_id;

        // if bound
        if (socket->port) {
                // release the port
                socket_port_release(global_sockets, socket);
        }
        
        // release all received packets
        while ((packet_id = dyn_fifo_pop(&socket->received)) >= 0)
                pq_release_remote(packet_phone, packet_id);

        dyn_fifo_destroy(&socket->received);
        dyn_fifo_destroy(&socket->accepted);

        if (socket_release)
                socket_release(socket);

        socket_cores_exclude(local_sockets, socket->socket_id);
}

/** Destroys local sockets.
 *
 * Releases all buffered packets and calls the release function for each of the
 * sockets.
 *
 * @param[in] packet_phone The packet server phone to release buffered packets.
 * @param[in] local_sockets The local sockets to be destroyed.
 * @param[in,out] global_sockets The global sockets to be updated.
 * @param[in] socket_release The client release callback function.
 */
void
socket_cores_release(int packet_phone, socket_cores_ref local_sockets,
    socket_ports_ref global_sockets,
    void (* socket_release)(socket_core_ref socket))
{
        int index;

        if (!socket_cores_is_valid(local_sockets))
                return;

        local_sockets->magic = 0;

        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(packet_phone,
                                    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.
 * @returns             EOK on success.
 * @returns             ENOMEM if there is not enough memory left.
 */
static int
socket_port_add_core(socket_port_ref socket_port, socket_core_ref socket,
    const char *key, size_t key_length)
{
        socket_core_ref *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.
 * @returns             EOK on success.
 * @returns             ENOMEM if there is not enough memory left.
 * @returns             Other error codes as defined for the
 *                       socket_ports_add() function.
 */
static int
socket_bind_insert(socket_ports_ref global_sockets, socket_core_ref socket,
    int port)
{
        socket_port_ref 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, SOCKET_MAP_KEY_LISTENING,
            0);
        if (rc != EOK)
                goto fail;
        
        // register the incomming 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(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.
 * @returns             EOK on success.
 * @returns             ENOTSOCK if the socket was not found.
 * @returns             EAFNOSUPPORT if the address family is not supported.
 * @returns             EADDRINUSE if the port is already in use.
 * @returns             Other error codes as defined for the
 *                      socket_bind_free_port() function.
 * @returns             Other error codes as defined for the
 *                      socket_bind_insert() function.
 */
int
socket_bind(socket_cores_ref local_sockets, socket_ports_ref global_sockets,
    int socket_id, void *addr, size_t addrlen, int free_ports_start,
    int free_ports_end, int last_used_port)
{
        socket_core_ref socket;
        socket_port_ref 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.
 * @returns             EOK on success.
 * @returns             ENOTCONN if no free port was found.
 * @returns             Other error codes as defined for the
 *                      socket_bind_insert() function.
 */
int
socket_bind_free_port(socket_ports_ref global_sockets, socket_core_ref 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;
                
                // til the range end
                if (index >= free_ports_end) {
                        // start from the range beginning
                        index = free_ports_start - 1;
                        do {
                                ++index;
                                // til 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.
 * @returns             The new socket identifier.
 * @returns             ELIMIT if there is no socket identifier available.
 */
static int socket_generate_new_id(socket_cores_ref local_sockets, int positive)
{
        int socket_id;
        int count;

        count = 0;
//      socket_id = socket_globals.last_id;
        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;
/*                      } else if(socket_globals.last_id) {
*                               socket_globals.last_id = 0;
*                               socket_id = 1;
*/                      } else {
                                return ELIMIT;
                        }
                }
        } while (socket_cores_find(local_sockets,
            ((positive ? 1 : -1) * socket_id)));
        
//      last_id = socket_id
        return socket_id;
}

/** Creates a new socket.
 *
 * @param[in,out] local_sockets The local sockets to be updated.
 * @param[in] app_phone The application phone.
 * @param[in] specific_data The socket specific data.
 * @param[in,out] socket_id The new socket identifier. A new identifier is
 *                      chosen if set to zero or negative. A negative identifier
 *                      is chosen if set to negative.
 * @returns             EOK on success.
 * @returns             EINVAL if the socket_id parameter is NULL.
 * @returns             ENOMEM if there is not enough memory left.
 */
int
socket_create(socket_cores_ref local_sockets, int app_phone,
    void *specific_data, int *socket_id)
{
        socket_core_ref 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_ref) malloc(sizeof(*socket));
        if (!socket)
                return ENOMEM;
        
        // initialize
        socket->phone = app_phone;
        socket->port = -1;
        socket->key = NULL;
        socket->key_length = 0;
        socket->specific_data = specific_data;
        rc = dyn_fifo_initialize(&socket->received, SOCKET_INITIAL_RECEIVED_SIZE);
        if (rc != EOK) {
                free(socket);
                return rc;
        }
        
        rc = dyn_fifo_initialize(&socket->accepted, SOCKET_INITIAL_ACCEPTED_SIZE);
        if (rc != EOK) {
                dyn_fifo_destroy(&socket->received);
                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->received);
                dyn_fifo_destroy(&socket->accepted);
                free(socket);
                return rc;
        }
        
        return EOK;
}

/** Destroys the socket.
 *
 * If the socket is bound, the port is released.
 * Releases all buffered packets, calls the release function and removes the
 * socket from the local sockets.
 *
 * @param[in] packet_phone The packet server phone to release buffered packets.
 * @param[in] socket_id The socket identifier.
 * @param[in,out] local_sockets The local sockets to be updated.
 * @param[in,out] global_sockets The global sockets to be updated.
 * @param[in] socket_release The client release callback function.
 * @returns             EOK on success.
 * @returns             ENOTSOCK if the socket is not found.
 */
int
socket_destroy(int packet_phone, int socket_id, socket_cores_ref local_sockets,
    socket_ports_ref global_sockets,
    void (*socket_release)(socket_core_ref socket))
{
        socket_core_ref socket;
        int accepted_id;

        // find the socket
        socket = socket_cores_find(local_sockets, socket_id);
        if (!socket)
                return ENOTSOCK;
        
        // destroy all accepted sockets
        while ((accepted_id = dyn_fifo_pop(&socket->accepted)) >= 0)
                socket_destroy(packet_phone, accepted_id, local_sockets,
                    global_sockets, socket_release);
        
        socket_destroy_core(packet_phone, socket, local_sockets, global_sockets,
            socket_release);
        
        return EOK;
}

/** Replies the packet or the packet queue data to the application via the
 * socket.
 *
 * Uses the current message processing fibril.
 *
 * @param[in] packet    The packet to be transfered.
 * @param[out] length   The total data length.
 * @returns             EOK on success.
 * @returns             EBADMEM if the length parameter is NULL.
 * @returns             ENOMEM if there is not enough memory left.
 * @returns             Other error codes as defined for the data_reply()
 *                      function.
 */
int socket_reply_packets(packet_t packet, size_t *length)
{
        packet_t next_packet;
        size_t fragments;
        size_t *lengths;
        size_t index;
        int rc;

        if (!length)
                return EBADMEM;

        next_packet = pq_next(packet);
        if (!next_packet) {
                // write all if only one fragment
                rc = data_reply(packet_get_data(packet),
                    packet_get_data_length(packet));
                if (rc != EOK)
                        return rc;
                // store the total length
                *length = packet_get_data_length(packet);
        } else {
                // count the packet fragments
                fragments = 1;
                next_packet = pq_next(packet);
                while ((next_packet = pq_next(next_packet)))
                        ++fragments;
                
                // compute and store the fragment lengths
                lengths = (size_t *) malloc(sizeof(size_t) * fragments +
                    sizeof(size_t));
                if (!lengths)
                        return ENOMEM;
                
                lengths[0] = packet_get_data_length(packet);
                lengths[fragments] = lengths[0];
                next_packet = pq_next(packet);
                
                for (index = 1; index < fragments; ++index) {
                        lengths[index] = packet_get_data_length(next_packet);
                        lengths[fragments] += lengths[index];
                        next_packet = pq_next(packet);
                }
                
                // write the fragment lengths
                rc = data_reply(lengths, sizeof(int) * (fragments + 1));
                if (rc != EOK) {
                        free(lengths);
                        return rc;
                }
                next_packet = packet;
                
                // write the fragments
                for (index = 0; index < fragments; ++index) {
                        rc = data_reply(packet_get_data(next_packet),
                            lengths[index]);
                        if (rc != EOK) {
                                free(lengths);
                                return rc;
                        }
                        next_packet = pq_next(next_packet);
                }
                
                // store the total length
                *length = lengths[fragments];
                free(lengths);
        }
        
        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.
 * @returns             The found socket.
 * @returns             NULL if no socket was found.
 */
socket_core_ref
socket_port_find(socket_ports_ref global_sockets, int port, const char *key,
    size_t key_length)
{
        socket_port_ref socket_port;
        socket_core_ref *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_ref global_sockets, socket_core_ref socket)
{
        socket_port_ref socket_port;
        socket_core_ref *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);
                                // release the port
                                socket_ports_exclude(global_sockets,
                                    socket->port);
                        } else {
                                // remove
                                socket_port_map_exclude(&socket_port->map,
                                    socket->key, socket->key_length);
                        }
                }
        }
        
        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.
 * @returns             EOK on success.
 * @returns             ENOENT if the port is not already used.
 * @returns             Other error codes as defined for the
 *                      socket_port_add_core() function.
 */
int
socket_port_add(socket_ports_ref global_sockets, int port,
    socket_core_ref socket, const char *key, size_t key_length)
{
        socket_port_ref 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;
}

/** @}
 */