module.c

无线网络路有协议aodv的 linux的实现

/***************************************************************************
                          module.c  -  description
                             -------------------
    begin                : Wed Aug 20 2003
    copyright            : (C) 2003 by Luke Klein-Berndt
    email                : [e-mail]
 ***************************************************************************/

#include "module.h"
 
struct nf_hook_ops input_filter;
struct nf_hook_ops output_filter;

extern struct timer_list aodv_timer;

aodv_route *g_my_route;  
u_int32_t   g_my_ip;  
u_int32_t 	g_broadcast_ip;

#ifdef LINK_LIMIT
int		g_link_limit = 15; //signal - noise, needs to be above this to be a neighbor...
#endif

int32_t			g_score_threshold = HELLO_INTERVAL;
u_int64_t   g_last_hello;
u_int32_t g_local_subnet;
u_int8_t g_aodv_gateway;
static struct proc_dir_entry *aodv_dir, *route_table_proc, *neigh_proc;

char *use_dev;
char *aodv_subnet;
char *local_subnet;

u_int8_t aodv_gateway;
MODULE_PARM(use_dev,"s");
MODULE_PARM(aodv_gateway,"i");
MODULE_PARM(local_subnet,"s");



MODULE_LICENSE("GPL");
MODULE_AUTHOR("Luke Klein-Berndt");
MODULE_DESCRIPTION("A AODV ad-hoc routing kernel module");



char g_aodv_dev[8];


/****************************************************

	init_module
----------------------------------------------------
This is called by insmod when things get
started up!
****************************************************/

int init_module(void)
{
    int result;
    char* local_subnet_netmask_str;
    u_int32_t local_subnet_ip=0;
    u_int32_t local_subnet_netmask=0;
    aodv_route *tmp_route;

    

    
    if (use_dev==NULL)
    {
    		printk("You need to specify which device to use, ie:\n");
      	printk("    insmod kernel_aod use_dev=wlan0    \n");
       	return(-1);
        strcpy(g_aodv_dev,"");
    }
    else
        strcpy(g_aodv_dev,use_dev);

		g_aodv_gateway = aodv_gateway;


    inet_aton("255.255.255.255",&g_broadcast_ip);
    printk("\n-=: Kernel AODV v2.2 :=-\nLuke Klein-Berndt\nWireless Communications Technologies Group\nNational Institue of Standards and Technology\n");
    printk("---------------------------------------------\n");
    
    //netfilter stuff
    
    // input hook 
    input_filter.list.next = NULL;
    input_filter.list.prev = NULL;
    input_filter.hook = input_handler;
    input_filter.pf = PF_INET; // IPv4
    input_filter.hooknum = NF_IP_PRE_ROUTING;

    // output hook 
    output_filter.list.next = NULL;
    output_filter.list.prev = NULL;
    output_filter.hook = output_handler;
    output_filter.pf = PF_INET; // IPv4
    output_filter.hooknum = NF_IP_POST_ROUTING;


    init_aodv_route_table();

    if (local_subnet==NULL)
        g_local_subnet=0;
    else
    {
    		local_subnet_netmask_str = strchr(local_subnet,'/');
      	if ( local_subnet_netmask_str)
       	{	(*local_subnet_netmask_str)='\0';
          local_subnet_netmask_str++;
          printk("Adding Localy Routed Subnet %s/%s to the routing table...\n",local_subnet, local_subnet_netmask_str);
	        inet_aton(local_subnet, &local_subnet_ip);
	        inet_aton(local_subnet_netmask_str, &local_subnet_netmask);
	        tmp_route = create_aodv_route(local_subnet_ip);
	        tmp_route->route_valid = TRUE;
	        tmp_route->route_seq_valid = TRUE;
	        tmp_route->netmask = local_subnet_netmask;
	        tmp_route->self_route = TRUE;
	        tmp_route->metric = 1;
	        tmp_route->seq = 1;
	        tmp_route->rreq_id = 1;
	      }

    }


    
    
    init_task_queue();
    init_timer_queue();
    init_flood_id_queue();
    init_aodv_neigh_list();
    init_packet_queue();
    
	

	if (!init_aodv_dev())
	{
   	del_timer(&aodv_timer);
    printk("Kernel_AODV: Removed timer...\n");

    printk("Kernel_AODV: Killed router thread...\n");
		cleanup_packet_queue();
    cleanup_task_queue();
    cleanup_flood_id_queue();
		printk("Kernel_AODV: Cleaned up AODV Queues...\n");
    cleanup_aodv_route_table();
	  return(-1);
	}

    #ifdef AODV_SIGNAL
     init_iw_sock();

    printk("Kernel_AODV: A Maximum of: %d neighboring nodes' signals can be monitored\n",IW_MAX_SPY);
     #endif
startup_aodv();

    result = nf_register_hook(&output_filter);
    result = nf_register_hook(&input_filter);
    
#ifdef MESSAGES
    printk("Kernel_AODV: Principal IP address - %s\n",inet_ntoa(g_my_ip));
    if (g_aodv_gateway)
    {
    	printk("Kernel_AODV: Set as AODV Gateway\n");
    }

#endif


    insert_timer( TASK_CLEANUP, HELLO_INTERVAL, g_my_ip);
    update_timer_queue();


    aodv_dir = proc_mkdir("aodv",NULL);
    aodv_dir->owner = THIS_MODULE;
    
    route_table_proc=create_proc_read_entry("aodv/routes", 0, NULL, read_route_table_proc, NULL);
    route_table_proc->owner=THIS_MODULE;

    route_table_proc=create_proc_read_entry("aodv/neigh", 0, NULL, read_neigh_proc, NULL);
    route_table_proc->owner=THIS_MODULE;
  
    route_table_proc=create_proc_read_entry("aodv/timers", 0, NULL, read_timer_queue_proc, NULL);
    route_table_proc->owner=THIS_MODULE;

    route_table_proc=create_proc_read_entry("aodv/flood_id", 0, NULL, read_flood_id_proc, NULL);
    route_table_proc->owner=THIS_MODULE;
    return 0;
}


/****************************************************

   cleanup_module
----------------------------------------------------
cleans up the module. called by rmmod
****************************************************/
void cleanup_module(void)
{
      remove_proc_entry("aodv/routes",NULL);
      remove_proc_entry("aodv/flood_id",NULL);
      remove_proc_entry("aodv/timers",NULL);
      remove_proc_entry("aodv/neigh",NULL);
	    remove_proc_entry("aodv", NULL);

  

    printk("Kernel_AODV: Shutting down...\n");


    nf_unregister_hook(&input_filter);
    nf_unregister_hook(&output_filter);
  
    printk("Kernel_AODV: Unregistered NetFilter hooks...\n");

    close_sock();

#ifdef AODV_SIGNAL
    close_iw_sock();
#endif
    printk("Kernel_AODV: Closed sockets...\n");

   	del_timer(&aodv_timer);
    printk("Kernel_AODV: Removed timer...\n");


    kill_aodv();
    printk("Kernel_AODV: Killed router thread...\n");


    cleanup_task_queue();
    cleanup_flood_id_queue();
    cleanup_packet_queue();
		printk("Kernel_AODV: Cleaned up AODV Queues...\n");

    cleanup_aodv_route_table();
    printk("Kernel_AODV: Cleaned up Route Table...\n");



    printk("Kernel_AODV: Shutdown complete!\n");
}