module.c

一种AODV实现方法

/*
               Kernel AODV  v2.0
National 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 not
sure how much of it is left anymore, but MadHoc
proved to be a great starting point.

MadHoc was written by - Fredrik Lilieblad,
Oskar Mattsson, Petra Nylund, Dan Ouchterlony
and Anders Roxenhag Mail: [e-mail]

This software is Open Source under the GNU General Public Licence.

*/

#include "module.h"
#ifdef ARM
#define EXPORT_SYMBOL_ALIAS ( __do_softirq, do_softirq);
#endif
/****************************************************

   module
----------------------------------------------------
These are the two functions which are used to
start things up and shut things down.
****************************************************/

static struct nf_hook_ops input_filter;
struct nf_hook_ops output_filter;

struct route_table_entry *g_my_entry;  // a pointer to my route entry in the table
u_int32_t        g_my_ip;  // my IP number, set on the command line
u_int32_t g_broadcast_ip;  // the broadcast address to use.
u_int8_t	use_lo;  //variable for command line options
char *block_dev;
char *aodv_dev;
char *aodv_subnet;

//entries for our different PROC files
static struct proc_dir_entry *aodv_dir, *route_table_proc, *rreq_id_proc, *timer_queue_proc, *monitor_proc;


MODULE_PARM(use_lo,"i");
MODULE_PARM(block_dev, "s");
MODULE_PARM(aodv_dev,"s");
MODULE_PARM(aodv_subnet,"s");

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

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

int init_module(void)
{
    int result;

    if (use_lo==0)
        USE_LO=0;
    else
        USE_LO=1;

    if (block_dev==NULL)
        strcpy(g_block_dev,"");
    else
        strcpy(g_block_dev,block_dev);

    if (aodv_dev==NULL)
        strcpy(g_aodv_dev,"");
    else
        strcpy(g_aodv_dev,aodv_dev);

    if (aodv_subnet==NULL)
        g_aodv_subnet=0;
    else
    {
        inet_aton(aodv_subnet, &g_aodv_subnet);
    }
    inet_aton("255.255.255.255",&g_broadcast_ip);
    printk("\n-=: Kernel AODV v1.5 :=-\nLuke Klein-Berndt\nWireless Communications Technologies Group\nNational Institue of Standards and Technology\n");
    printk("---------------------------------------------\n");

    //netfilter stuff
    init_packet_queue();

    /* 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_LOCAL_IN;

    /* 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_LOCAL_OUT;

    init_timer_queue();
    init_rreq_id_queue();
    init_event_queue();
    init_route_table();
    init_iw_sock();
    init_interface_list();
    init_neighbor_list();
    startup_aodv();

    /* hooks registration */
    result = nf_register_hook(&input_filter);
    if (result)
        goto hook_failed;

#ifdef TRACE
    printk("Kernel_AODV: Input filter registered!\n");
#endif

    result = nf_register_hook(&output_filter);
    if (result)
        goto hook_failed;

#ifdef TRACE
    printk("Kernel_AODV: Output filter registered!\n");
#endif

#ifdef MESSAGES
    printk("Kernel_AODV: Principal IP address - %s\n",inet_ntoa(g_my_ip));
#endif

    insert_timer_queue_entry(getcurrtime() + ACTIVE_ROUTE_TIMEOUT, NULL,0,g_my_ip,0,0, EVENT_CLEANUP);
    update_timer_queue();

    //setup the proc file system
    aodv_dir=proc_mkdir("aodv",NULL);
    aodv_dir->owner=THIS_MODULE;
    route_table_proc=create_proc_read_entry("aodv/route_table", 0, NULL, read_route_table_proc, NULL);
    route_table_proc->owner=THIS_MODULE;
    rreq_id_proc=create_proc_read_entry("aodv/rreq_id_queue", 0, NULL, read_rreq_id_proc, NULL);
    rreq_id_proc->owner=THIS_MODULE;
    timer_queue_proc=create_proc_read_entry("aodv/timer_queue", 0, NULL, read_timer_queue_proc, NULL);
    timer_queue_proc->owner=THIS_MODULE;
    monitor_proc=create_proc_read_entry("aodv/monitor", 0, NULL, read_monitor_proc, NULL);
    monitor_proc->owner=THIS_MODULE;


    //starts aodv thread

    return 0;

hook_failed:
#ifndef NO_ERROR
    printk(KERN_INFO "Kernel_AODV: error registering hook (%d)", result);
#endif

    return 1;

}


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

   cleanup_module
----------------------------------------------------
cleans up the module. called by rmmod
****************************************************/
void cleanup_module(void)
{

    //get rid of all our proc files
    remove_proc_entry("aodv/monitor",NULL);
    remove_proc_entry("aodv/route_table",NULL);
    remove_proc_entry("aodv/rreq_id_queue", NULL);
    remove_proc_entry("aodv/timer_queue", NULL);
    remove_proc_entry("aodv", NULL);

    /* unregister hooks */

#ifdef MESSAGES
    printk("Kernel_AODV: Shutting down...\n");
#endif

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

    cleanup_packet_queue();
    cleanup_event_queue();
    cleanup_rreq_id_queue();

#ifdef MESSAGES
    printk("Kernel_AODV: Cleaned up AODV Queues...\n");
#endif

    kill_aodv();

#ifdef MESSAGES
    printk("Kernel_AODV: Killed router thread...\n");
#endif

    del_timer(&aodv_timer);

#ifdef MESSAGES
    printk("Kernel_AODV: Removed timer...\n");
#endif

    cleanup_route_table();

#ifdef MESSAGES
    printk("Kernel_AODV: Cleaned up Route Table...\n");
#endif

    close_sock();
    close_iw_sock();

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

#ifdef MESSAGES
    printk("Kernel_AODV: Shutdown complete!\n");
#endif
}