bb_udp.c

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 * The Kannel Software License, Version 1.0 
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 */ 

/*
 * bb_udpc.c : bearerbox UDP sender/receiver module
 *
 * handles start/restart/shutdown/suspend/die operations of the UDP
 * WDP interface
 *
 * Kalle Marjola <rpr@wapit.com> 2000 for project Kannel
 */

#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <assert.h>

#include "gwlib/gwlib.h"
#include "msg.h"
#include "bearerbox.h"

/* passed from bearerbox core */

extern volatile sig_atomic_t bb_status;
extern List *incoming_wdp;

extern Counter *incoming_wdp_counter;
extern Counter *outgoing_wdp_counter;

extern List *flow_threads;
extern List *suspended;
extern List *isolated;

/* our own thingies */

static volatile sig_atomic_t udp_running;
static List *udpc_list;


typedef struct _udpc {
    int fd;
    Octstr *addr;
    List *outgoing_list;
    long receiver;
} Udpc;


/*
 * IP numbers which are allowed or denied us of the bearerbox via UDP.
 */
static Octstr *allow_ip;
static Octstr *deny_ip;


/* forward declarations */

static void udpc_destroy(Udpc *udpc);

/*-------------------------------------------------
 *  receiver thingies
 */

static void udp_receiver(void *arg)
{
    Octstr *datagram, *cliaddr;
    int ret;
    Msg *msg;
    Udpc *conn = arg;
    Octstr *ip;

    gwlist_add_producer(incoming_wdp);
    gwlist_add_producer(flow_threads);
    gwthread_wakeup(MAIN_THREAD_ID);
    
    /* remove messages from socket until it is closed */
    while (bb_status != BB_DEAD && bb_status != BB_SHUTDOWN) {

    gwlist_consume(isolated);   /* block here if suspended/isolated */

    if (read_available(conn->fd, 100000) < 1)
        continue;

    ret = udp_recvfrom(conn->fd, &datagram, &cliaddr);
    if (ret == -1) {
        if (errno == EAGAIN)
        /* No datagram available, don't block. */
        continue;

        error(errno, "Failed to receive an UDP");
        /*
         * just continue, or is there ANY error that would result
         * in situation where it would be better to break; or even
         * die off?     - Kalle 28.2
         */
        continue;
    }

    /* discard the message if the client is not allowed */
        ip = udp_get_ip(cliaddr);
    if (!is_allowed_ip(allow_ip, deny_ip, ip)) {
            warning(0, "UDP: Discarding packet from %s, IP is denied.",
               octstr_get_cstr(ip));
            octstr_destroy(datagram);
    } else {
        debug("bb.udp", 0, "datagram received");
        msg = msg_create(wdp_datagram);
    
        msg->wdp_datagram.source_address = udp_get_ip(cliaddr);
        msg->wdp_datagram.source_port    = udp_get_port(cliaddr);
        msg->wdp_datagram.destination_address = udp_get_ip(conn->addr);
        msg->wdp_datagram.destination_port    = udp_get_port(conn->addr);
        msg->wdp_datagram.user_data = datagram;
    
        gwlist_produce(incoming_wdp, msg);
        counter_increase(incoming_wdp_counter);
    }

    octstr_destroy(cliaddr);
    octstr_destroy(ip);
    }    
    gwlist_remove_producer(incoming_wdp);
    gwlist_remove_producer(flow_threads);
}


/*---------------------------------------------
 * sender thingies
 */

static int send_udp(int fd, Msg *msg)
{
    Octstr *cliaddr;
    int ret;

    cliaddr = udp_create_address(msg->wdp_datagram.destination_address,
                 msg->wdp_datagram.destination_port);
    ret = udp_sendto(fd, msg->wdp_datagram.user_data, cliaddr);
    if (ret == -1)
    error(0, "WDP/UDP: could not send UDP datagram");
    octstr_destroy(cliaddr);
    return ret;
}


static void udp_sender(void *arg)
{
    Msg *msg;
    Udpc *conn = arg;

    gwlist_add_producer(flow_threads);
    while(bb_status != BB_DEAD) {

    gwlist_consume(suspended);  /* block here if suspended */

    if ((msg = gwlist_consume(conn->outgoing_list)) == NULL)
        break;

    debug("bb.udp", 0, "udp: sending message");
    
        if (send_udp(conn->fd, msg) == -1)
        /* ok, we failed... tough
         * XXX log the message or something like that... but this
         * is not as fatal as it is with SMS-messages...
         */ {
        msg_destroy(msg);
        continue;
    }
    counter_increase(outgoing_wdp_counter);
    msg_destroy(msg);
    }
    gwthread_join(conn->receiver);

    udpc_destroy(conn);
    gwlist_remove_producer(flow_threads);
}

/*---------------------------------------------------------------
 * accept/create thingies
 */


static Udpc *udpc_create(int port, char *interface_name)
{
    Udpc *udpc;
    Octstr *os;
    int fl;
    
    udpc = gw_malloc(sizeof(Udpc));
    udpc->fd = udp_bind(port, interface_name);

    os = octstr_create(interface_name);
    udpc->addr = udp_create_address(os, port);
    octstr_destroy(os);
    if (udpc->addr == NULL) {
    error(0, "updc_create: could not resolve interface <%s>",
          interface_name);
    close(udpc->fd);
    gw_free(udpc);
    return NULL;
    }

    fl = fcntl(udpc->fd, F_GETFL);
    fcntl(udpc->fd, F_SETFL, fl | O_NONBLOCK);

    os = udp_get_ip(udpc->addr);
    debug("bb.udp", 0, "udpc_create: Bound to UDP <%s:%d>",
      octstr_get_cstr(os), udp_get_port(udpc->addr));

    octstr_destroy(os);
    
    udpc->outgoing_list = gwlist_create();

    return udpc;
}    


static void udpc_destroy(Udpc *udpc)
{
    if (udpc == NULL)
    return;

    if (udpc->fd >= 0)
    close(udpc->fd);
    octstr_destroy(udpc->addr);
    gw_assert(gwlist_len(udpc->outgoing_list) == 0);
    gwlist_destroy(udpc->outgoing_list, NULL);

    gw_free(udpc);
}    


static int add_service(int port, char *interface_name)
{
    Udpc *udpc;
    
    if ((udpc = udpc_create(port, interface_name)) == NULL)
    goto error;
    gwlist_add_producer(udpc->outgoing_list);

    udpc->receiver = gwthread_create(udp_receiver, udpc);
    if (udpc->receiver == -1)
    goto error;

    if (gwthread_create(udp_sender, udpc) == -1)
    goto error;

    gwlist_append(udpc_list, udpc);
    return 0;
    
error:    
    error(0, "Failed to start UDP receiver/sender thread");
    udpc_destroy(udpc);
    return -1;
}



/*-------------------------------------------------------------
 * public functions
 *
 */

int udp_start(Cfg *cfg)
{
    CfgGroup *grp;
    Octstr *iface;
    List *ifs;
    int allow_wtls;
    
    if (udp_running) return -1;
    
    debug("bb.udp", 0, "starting UDP sender/receiver module");

    grp = cfg_get_single_group(cfg, octstr_imm("core"));
    iface = cfg_get(grp, octstr_imm("wdp-interface-name"));
    if (iface == NULL) {
        error(0, "Missing wdp-interface-name variable, cannot start UDP");
        return -1;
    }

    allow_ip = cfg_get(grp, octstr_imm("udp-allow-ip"));
    deny_ip = cfg_get(grp, octstr_imm("udp-deny-ip"));

    /*  we'll activate WTLS as soon as we have a 'wtls' config group */
    grp = cfg_get_single_group(cfg, octstr_imm("wtls"));
    allow_wtls = grp != NULL ? 1 : 0;

    udpc_list = gwlist_create();    /* have a list of running systems */

    ifs = octstr_split(iface, octstr_imm(";"));
    octstr_destroy(iface);
    while (gwlist_len(ifs) > 0) {
        iface = gwlist_extract_first(ifs);
    info(0, "Adding interface %s", octstr_get_cstr(iface));
        add_service(9200, octstr_get_cstr(iface));   /* wsp     */
        add_service(9201, octstr_get_cstr(iface));   /* wsp/wtp */
    
#ifdef HAVE_WTLS_OPENSSL
        if (allow_wtls) {
             add_service(9202, octstr_get_cstr(iface));   /* wsp/wtls   */
             add_service(9203, octstr_get_cstr(iface));   /* wsp/wtp/wtls */
        }
#else
        if (allow_wtls)
             error(0, "These is a 'wtls' group in configuration, but no WTLS support compiled in!");
#endif
    /* add_service(9204, octstr_get_cstr(interface_name));  * vcard */
    /* add_service(9205, octstr_get_cstr(interface_name));  * vcal  */
    /* add_service(9206, octstr_get_cstr(interface_name));  * vcard/wtls */
    /* add_service(9207, octstr_get_cstr(interface_name));  * vcal/wtls */
        octstr_destroy(iface);
    }
    gwlist_destroy(ifs, NULL);
    
    gwlist_add_producer(incoming_wdp);
    udp_running = 1;
    return 0;
}


/*
 * this function receives an WDP message and adds it to
 * corresponding outgoing_list.
 */
int udp_addwdp(Msg *msg)
{
    int i;
    Udpc *udpc, *def_udpc;
    Octstr *ip;
    
    def_udpc = NULL;
    if (!udp_running) return -1;
    assert(msg != NULL);
    assert(msg_type(msg) == wdp_datagram);
    
    gwlist_lock(udpc_list);
    /* select in which list to add this */
    for (i=0; i < gwlist_len(udpc_list); i++) {
        udpc = gwlist_get(udpc_list, i);

        if (msg->wdp_datagram.source_port == udp_get_port(udpc->addr)) {
                    def_udpc = udpc;
                    ip = udp_get_ip(udpc->addr);
            if (octstr_compare(msg->wdp_datagram.source_address, ip) == 0) {
                        octstr_destroy(ip);
                gwlist_produce(udpc->outgoing_list, msg);
                gwlist_unlock(udpc_list);
                return 0;
            }
                    octstr_destroy(ip);
        }
    }

    if (NULL != def_udpc) {
    gwlist_produce(def_udpc->outgoing_list, msg);
    gwlist_unlock(udpc_list);
    return 0;
    }

    gwlist_unlock(udpc_list);
    return -1;
}

int udp_shutdown(void)
{
    if (!udp_running) return -1;

    debug("bb.thread", 0, "udp_shutdown: Starting avalanche");
    gwlist_remove_producer(incoming_wdp);
    return 0;
}


int udp_die(void)
{
    Udpc *udpc;

    if (!udp_running) return -1;
    
    /*
     * remove producers from all outgoing lists.
     */
    debug("bb.udp", 0, "udp_die: removing producers from udp-lists");

    while((udpc = gwlist_consume(udpc_list)) != NULL) {
    gwlist_remove_producer(udpc->outgoing_list);
    }
    gwlist_destroy(udpc_list, NULL);
    udp_running = 0;
    
    octstr_destroy(allow_ip);
    octstr_destroy(deny_ip);
    allow_ip = NULL;
    deny_ip = NULL;
    
    return 0;
}


int udp_outgoing_queue(void)
{
    int i, q = 0;
    Udpc *udpc;

    if (!udp_running || udpc_list == NULL)
    return 0;

    gwlist_lock(udpc_list);
    for (i=0; i < gwlist_len(udpc_list); i++) {
    udpc = gwlist_get(udpc_list, i);
    q += gwlist_len(udpc->outgoing_list);
    }
    gwlist_unlock(udpc_list);
    return q;
}