void perform_opn(int choice)
{
switch(choice)
{
case 1:
disp_free_all();
break;
case 2:
read_write_stdin();
break;
case 3:
read_write_file();
break;
case 4:
disp_content();
break;
case 5:
free_single_pool();
break;
case 6:
destroy_mem();
printf("\n\nProgram Exited Successfully!!\n\n");
exit(0);
default:
printf("\nInvalid Operation Selected!!\n");
}
}
asmlinkage long xcrypt(void *arg)
{
/* dummy syscall: returns 0 for non null, -EINVAL for NULL */
struct inputs *mptr= NULL;
struct filename *infile= NULL;
struct filename *outfile= NULL;
char *key= NULL;
int rc;
printk("xcrypt received arg %p\n", arg);
if (arg == NULL)
return -EINVAL;
mptr = kmalloc(sizeof(struct inputs),GFP_KERNEL);
if(IS_ERR(mptr)){
printk("Error in allocating memory to input structure\n ");
rc = -PTR_ERR(mptr);
goto out;
}
rc= copy_from_user(mptr,arg,sizeof(struct inputs));
if(rc){
printk("Error in copying inputs from user \n");
rc= -EFAULT;
goto out;
}
infile= getname(mptr->in);
if(IS_ERR(infile)){
printk("getname() failed for filename of input file\n");
rc= -PTR_ERR(infile);
goto out;
}
outfile= getname(mptr->out);
if(IS_ERR(outfile)){
printk("getname() failed for filename of output file\n");
rc= -PTR_ERR(outfile);
goto out;
}
key= kmalloc(mptr->keylen,GFP_KERNEL);
if(IS_ERR(key)){
printk("Error allocating memory to key \n");
rc = -PTR_ERR(key);
goto out;
}
rc= copy_from_user(key,(char*)mptr->keybuf,mptr->keylen);
if(rc){
printk("Error copying key to kernel space \n");
rc=-EFAULT;
goto out;
}
rc= read_write_file(infile,outfile,(void*)key,mptr->flag);
if(rc < 0){
printk("Syscall xcrypt failed with error= %d \n",rc);
}
else{
printk("Successfully returned from syscall xcrypt\n");
}
out:
if(key)
kfree(key);
if(IS_ERR(outfile))
putname(outfile);
if(IS_ERR(infile))
putname(infile);
if(mptr)
kfree(mptr);
return rc;
}
