How to use get_random_bytes() in linux kernel module?

@viola_gleichner 

To use the get_random_bytes() function in a Linux kernel module, you need to follow these steps:

1. Include the necessary header file: Include the linux/random.h header file in your module source code to be able to use the get_random_bytes() function.

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#include <linux/random.h>

1. Declare a buffer: Declare a buffer of the required size to hold the random bytes you want to generate.

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#define BUF_SIZE 16
unsigned char buf[BUF_SIZE];

1. Generate random bytes: Use the get_random_bytes() function to generate random bytes into the declared buffer.

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get_random_bytes(buf, BUF_SIZE);

1. Use the generated random bytes: After calling get_random_bytes(), the buf array will be populated with random bytes. You can then use these bytes as needed in your kernel module.

Here's a simple example showing the usage of get_random_bytes():

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#include <linux/module.h>
#include <linux/random.h>

#define BUF_SIZE 16

unsigned char buf[BUF_SIZE];

static int __init my_init(void) {
    printk(KERN_INFO "Generating random bytes
");
    get_random_bytes(buf, BUF_SIZE);

    // Use the generated random bytes as needed

    return 0;
}

static void __exit my_exit(void) {
    // Cleanup if required
}

module_init(my_init);
module_exit(my_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Random Bytes Example");

Make sure to compile and install the kernel module using the appropriate build system (e.g., make or kbuild) for your specific kernel version.