تويت
simple character device
كود PHP:
#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kdev_t.h>
#include <linux/cdev.h>
#include <asm/uaccess.h>
static dev_t major;
static int test_ret;
static int param_major = 0 , param_minor = 0;
static struct cdev device_struct;
module_param(param_major , int , 0);
module_param(param_minor , int , 0);
/*static int storm_read(struct file *filp , */
static int device_open(struct inode *node , struct file *filp)
{
printk(KERN_ALERT"Device is opend\n");
}
static ssize_t device_read(struct file *filp , char __user *buf , size_t count , loff_t *off)
{
char *required;
if(count > 35)
count = 35;
required = kmalloc(count *sizeof(char) , GFP_KERNEL);
if(!required)
return ENOMEM;
memcpy(required , "Character device written by St0rM" , count);
if(copy_to_user(buf , required , count))
return EFAULT;
kfree(required);
return count;
}
static int init_device(void)
{
struct file_operation ops =
{
.owner = THIS_MODULE; /* Owner*/
.read = device_read; /* Device opned for read */
.open = device_open; /* Device opened */
};
if(param_major && param_minor)
{
major = MKDEV(param_major , param_minor);
test_ret = register_chrdev_region(majot , 1 , "storm");
}else
{
test_ret = alloc_chrdev_region(&major , 0 , 1 , "/dev/storm");
}
if(test_ret < 0)
{
test_ret = 2; /* Device number allocation error*/
return EFAULT; /* Uptill now nothing we should worry about */
}
printk(KERN_ALERT"Driver Major is ready\n");
cdev_init(&device_struct , &ops);
device_struct.owner = THIS_MODULE;
/* Here we should make sure that every thing is allright */
test_ret = cdev_add(&device_struct , dev , 1);
if(test_ret < 0)
{
exit_device();
test_ret = 3; /* device adding error */
return EFAULT;
}
}
static void exit_device(void)
{
pritnk(KERN_ALERT"cleaning up\n");
unregister_chrdev_region(major , 1);
if(test_ret == 3) /* device error , no need to remove it */
return;
cdev_del(device_struct);
}
module_init(init_device);
module_exit(exit_device);
MODULE_AUTHOR("St0rM-MaN");
MODULE_DESCRIPTION("Simple character device module sending out a message");
MODULE_DEVICE("/dev/storm");
MODULE_LICENSE("Gpl");
المهم يعني اهم حاجه هو ال device دوت وظيفته مش اكتر من انه
بيعمل driver جديد ويعمله register in kernel internal devices
وكل علي عليك بس انك تعمل
mknod /dev/storm c [major][minor]
بعد ماتعمل كده جرب مثلا تعمل cat /dev/storm مثلا
او تكتب برنامج صغير يفتح ال device ويقرا منه
كود PHP:
int fd = open("/dev/storm" , O_RDONLY);
read(fd , string , 20);
اااااه قبل مانسي
انا مش جربته اذن انا غير مسؤل عنه مش يجيلي واحد يقولي عملي crash في الكيرنيل بتاعي انا قلت اهوه
striker ياريت تكون اول واحد نجربه
بس بالراحه علي ال Shepard all this codes and topics is not for a real life use right now , until a good implementation is produced
codes are only for educational purpose
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