/*               Kernel AODV  v2.0National Institute of Standards and Technology               Luke Klein-Berndt-----------------------------------------------------  Version 2.0 new features:     * Updated to AODV draft version 11     * Managed internet gatewaying     * Monitor wireles signal strength     * Many bug fixes!-----------------------------------------------------Originally based upon MadHoc code. I am notsure how much of it is left anymore, but MadHocproved to be a great starting point.MadHoc was written by - Fredrik Lilieblad,Oskar Mattsson, Petra Nylund, Dan Ouchterlonyand Anders Roxenhag Mail: mad-hoc@flyinglinux.netThis software is Open Source under the GNU General Public Licence.*/#include "timer_queue.h"/****************************************************   timer_queue----------------------------------------------------A queue of timed events****************************************************/struct timer_queue_entry *timer_queue=NULL;extern struct route_table_entry *g_my_entry;extern u_int32_t g_broadcast_ip;extern u_int32_t g_my_ip;/****************************************************   read_timer_queue_proc----------------------------------------------------Prints out the current queue into a buffer whenever the proc file its read****************************************************/int read_timer_queue_proc(char *buffer, char **buffer_location, off_t offset, int buffer_length,int *eof,void *data){    struct timer_queue_entry *tmp;u_int64_t remainder, numerator;    u_int64_t tmp_time;    int len;    static char *my_buffer;    char temp_buffer[80];    my_buffer=buffer;    sprintf(my_buffer,"\nTimer Queue\n---------------------------------\n");    tmp = timer_queue;    while (tmp != NULL)    {        tmp_time=tmp->tv-getcurrtime();	//This is a fix for an error that occurs on ARM Linux Kernels because they do 64bits differently	//Thanks to S. Peter Li for coming up with this fix!	numerator = (tmp_time);	remainder = do_div( numerator, 1000 );	sprintf(temp_buffer,"sec/msec: %lu/%lu\t id:%s\t retries: %u\t ttl: %u\t Type: %d\n", (unsigned long)numerator, (unsigned long)remainder, inet_ntoa(tmp->id), tmp->retries, tmp->ttl,tmp->flags);	strcat(my_buffer,temp_buffer);        tmp = tmp->next;    }    sprintf(temp_buffer,"\n---------------------------------\n");    strcat(my_buffer,temp_buffer);    len = strlen(my_buffer);    if (len <= offset+buffer_length) *eof = 1;    *buffer_location = my_buffer + offset;    len -= offset;    if (len>buffer_length) len = buffer_length;    if (len<0) len = 0;    return len;}/****************************************************   print_timer----------------------------------------------------prints the contents of the timer queue to theconsole screen****************************************************/void print_timer_queue(){    struct timer_queue_entry *tmp;    u_int64_t tmp_time;	u_int64_t remainder, numerator;    tmp = timer_queue;    while (tmp != NULL)    {        tmp_time=tmp->tv-getcurrtime();	//This is a fix for an error that occurs on ARM Linux Kernels because they do 64bits differently	//Thanks to S. Peter Li for coming up with this fix!	numerator = tmp_time;	remainder = do_div( numerator, 1000 );	printk("sec/msec: %lu/%lu id:%lu size: %d retries: %u ttl: %u\n", (unsigned long)numerator, (unsigned long)remainder, (unsigned long)tmp->id, tmp->size, tmp->retries, tmp->ttl);        tmp = tmp->next;    }}/****************************************************   timer_rreq----------------------------------------------------Handles the resendinf of RREQ if a routereply is not recieved in a certian amount of time****************************************************/int timer_rreq(struct timer_queue_entry *tmp_entry){    struct route_table_entry *tmp_route;    struct rreq *tmp_rreq;    u_int64_t currtime;    tmp_rreq=tmp_entry->data;#ifdef TRACE    printk("TIMER_QUEUE: Timer RREQ entered \n");#endif    /* Check how may time we have sent it already */    if (tmp_entry->retries >= RREQ_RETRIES)    {        /* Sent it maximum times */#ifdef TRACE        printk("TIMER_QUEUE: Timer RREQ exiting...  retries used up! \n");#endif        ipq_drop_ip(tmp_rreq->dst_ip);        kfree(tmp_entry->data);        /* Return error */        return 1;    }    else    {        /* Increment nr of retries */        tmp_entry->retries++;        /* Check new TTL */        if (tmp_entry->ttl > TTL_THRESHOLD)            tmp_entry->ttl = NET_DIAMETER;        else            tmp_entry->ttl += TTL_INCREMENT;        tmp_route = (find_interface_by_ip(tmp_rreq->src_ip))->route_entry;        (tmp_route->rreq_id)++;        if (insert_rreq_id_queue_entry(tmp_rreq->src_ip, tmp_rreq->dst_ip,tmp_route->rreq_id,getcurrtime() + tmp_entry->ttl * 2 * NODE_TRAVERSAL_TIME) == 1)            /* Couldn't add to broadcast list */            return 1;        /* Send packet again */        local_broadcast( tmp_entry->ttl,tmp_rreq, tmp_entry->size);        /* Set a new timer */        currtime = getcurrtime();        insert_timer_queue_entry(currtime + NET_TRAVERSAL_TIME, tmp_rreq,tmp_entry->size,tmp_rreq->dst_ip,tmp_entry->retries,tmp_entry->ttl, EVENT_RREQ);#ifdef TRACE        printk("TIMER_QUEUE: Timer RREQ all done! \n");#endif    }    return 0;}void timer_neighbor(struct timer_queue_entry *timer_entry){    struct neighbor_list_entry  *tmp_entry;    struct route_table_entry *tmp_route;    tmp_entry = find_neighbor_list_entry(timer_entry->id);    if (tmp_entry!=NULL)    {        tmp_route=find_route_table_entry(tmp_entry->ip);        if (tmp_route!=NULL)        {#ifdef TRACE            printk("TIMER_QUEUE: The link to Neighbor: %s \n",inet_ntoa(tmp_entry->ip));#endif            //link_break(tmp_entry->ip);  we can't delete it directly because that would trigger an error because you are making changes to the route table on an interupt!!!            tmp_route->lifetime=0;            insert_event_queue_entry(g_my_ip,g_my_ip,NULL,NULL,EVENT_CLEANUP,0,NULL,0);            delete_neighbor_list_entry(tmp_entry->ip);        }    }}/****************************************************   hello_resend----------------------------------------------------Handles the resending of the Hello message andalso places the hello message back on thequeue so it will be called again****************************************************/int hello_resend(struct timer_queue_entry *tmp_entry){    struct rrep *tmp_rrep;    struct interface_list_entry *tmp_interface;    u_int64_t curr_time=getcurrtime();    u_int16_t random_number;    tmp_rrep=tmp_entry->data;    // we want to update the stats once every hello period    if (g_my_ip==tmp_rrep->dst_ip)        get_wireless_stats();#ifdef TRACE    printk("TIMER: Hello RESEND!\n");#endif    tmp_interface=find_interface_by_ip(tmp_rrep->dst_ip);    if (tmp_interface==NULL)    {#ifndef NO_ERROR        printk("HELLO_RESEND: error retrieveing interface\n");#endif        return 0;    }    tmp_rrep->dst_seq = htonl(tmp_interface->route_entry->dst_seq);    local_broadcast(1,tmp_rrep, sizeof(struct rrep));    get_random_bytes(&random_number,sizeof(u_int16_t));    random_number=random_number%20;    tmp_interface->last_hello=curr_time;    insert_timer_queue_entry(tmp_entry->tv + HELLO_INTERVAL-random_number, tmp_rrep,tmp_entry->size,tmp_rrep->dst_ip,tmp_entry->retries,tmp_entry->ttl, EVENT_HELLO);#ifdef TRACE    printk("TIMER: Hello RESEND! - all done!\n");#endif    return 0;}/****************************************************   timer_cleanup----------------------------------------------------Gets rid of everything in the timer queue.Should be called before you shutdown the module****************************************************/void timer_cleanup(){#ifdef TRACE    printk("timer cleanup entered!\n");#endif    insert_event_queue_entry(g_my_ip,g_my_ip,NULL,NULL,EVENT_CLEANUP,0,NULL,0);    insert_timer_queue_entry(getcurrtime() + ACTIVE_ROUTE_TIMEOUT, NULL,0,g_my_ip,0,0, EVENT_CLEANUP);#ifdef TRACE    printk("timer cleanup exited!\n");#endif}/****************************************************   init_timer_queue----------------------------------------------------Initalizes the timer queue... duh!****************************************************/int init_timer_queue(){    init_timer(&aodv_timer);    timer_queue=NULL;    return 0;}/****************************************************   update_timer_queue----------------------------------------------------Sets the  system alarm for the first event in thetimer queue****************************************************/static unsigned long tvtojiffies(struct timeval *value){    unsigned long sec = (unsigned) value->tv_sec;    unsigned long usec = (unsigned) value->tv_usec;u_int64_t numerator, numerator1;	//This is a fix for an error that occurs on ARM Linux Kernels because they do 64bits differently	//Thanks to S. Peter Li for coming up with this fix!    numerator = ULONG_MAX;    do_div( numerator, HZ );    if (sec > (unsigned long) numerator)        return ULONG_MAX;    numerator = 1000000;    do_div( numerator, HZ );    usec += numerator - 1;    numerator1 = usec;    do_div( numerator1,  numerator );    usec = numerator1;    return HZ*sec+usec;}void update_timer_queue(){    struct timeval delay_time;    u_int64_t currtime;    u_int64_t tv;u_int64_t remainder, numerator;    delay_time.tv_sec = 0;    delay_time.tv_usec = 0;#ifdef TRACE    printk("PQ_UPDATETIMER: entered\n");#endif    if (timer_queue == NULL)    {        // No event to set timer for        delay_time.tv_sec = 0;        delay_time.tv_usec = 0;    }    else    {        //* Get the first time value        tv = timer_queue->tv;        currtime = getcurrtime();        if (tv <= currtime)