acd_check.c

自己写的入侵检测源码

int find_canshuo(struct canshuo *canshuo_a,struct canshuo *canshuo_b);
int find_systemcall(exe_acd_struct *exe_acd_struct_a,exe_acd_struct *exe_acd_struct_b);
int find_feifa_xinxi_node(exe_acd_struct *exe_acd_struct_a,exe_acd_struct *exe_acd_struct_b);
int check_acd();

int find_canshuo(struct canshuo *canshuo_a,struct canshuo *canshuo_b)
{
  while(1)
  {
	  if(canshuo_a!=NULL&&canshuo_b!=NULL)
	  {
		  if(strcmp(canshuo_a->canshuo_name,canshuo_b->canshuo_name)==0)
		  {
			  canshuo_a=canshuo_a->next;
			  canshuo_b=canshuo_b->next;
		  }
		  else
		 {       return 0;
			  break;
		  }
	  }
	  else
	  {
		  if(canshuo_a==NULL&&canshuo_b==NULL)
		  {
			  return 1;
		  }
		  else
		  {
			  return 0;
		  }
	  }
	  
  }
}
int find_systemcall(exe_acd_struct *exe_acd_struct_a,exe_acd_struct *exe_acd_struct_b)
{
	int i,flag;
	i=0;
	flag=1;
	for(i=0;i<SYSTEMCALL_COUNT;i++)
	{  
		if(strcmp(exe_acd_struct_a->systemcall_list[i].systemcall_name,"$")==0)
		{
			if(strcmp(exe_acd_struct_b->systemcall_list[i].systemcall_name,"$")!=0)
			{
				flag=0;
				break;
			}
		else
			{
				break;
			}
		}
		if(strcmp(exe_acd_struct_b->systemcall_list[i].systemcall_name,"$")==0)
		{
			if(strcmp(exe_acd_struct_a->systemcall_list[i].systemcall_name,"$")!=0)
			{
				flag=0;
				break;
			} 
		}
		if(exe_acd_struct_a->systemcall_list[i].process_number==exe_acd_struct_b->systemcall_list[i].process_number)
		{	
			if(exe_acd_struct_a->systemcall_list[i].count==exe_acd_struct_b->systemcall_list[i].count)
			{
				if(find_canshuo(exe_acd_struct_a->systemcall_list[i].head,exe_acd_struct_b->systemcall_list[i].head))
				{
					continue;
				}
				else
				{
					flag=0;
					break;
				}
			}
			else
			{
				flag=0;
				break;
				
			}
		}
		else
		{
			flag=0;
			break;
		}
	}
	return flag;
}

int find_feifa_xinxi_node(exe_acd_struct *exe_acd_struct_a,exe_acd_struct *exe_acd_struct_b)
{
	int flag;
	flag=0;
	if(exe_acd_struct_a!=NULL&&exe_acd_struct_b!=NULL)
	{
		if(exe_acd_struct_a->exe_file_name_node.right>=exe_acd_struct_b->exe_file_name_node.right)
		{
			if(find_systemcall(exe_acd_struct_a,exe_acd_struct_b))
			{
				flag=1;
			}
		}
	}
	return flag;

}


int check_acd(exe_acd_struct *	feifa_diaoyong_file)
{ 
		
	int flag=0;
	int i=0;
	struct feifa_xinxi_struct *p1,*p2;
    
	p1=(struct feifa_xinxi_struct * )kmalloc(sizeof(struct feifa_xinxi_struct),0);
	p2=(struct feifa_xinxi_struct * )kmalloc(sizeof(struct feifa_xinxi_struct),0);
	p1->feifa_xinxi_node=(struct exe_acd_struct * )kmalloc(sizeof(struct exe_acd_struct),0);
	

	acd_head1=(struct feifa_xinxi_struct * )kmalloc(sizeof(struct feifa_xinxi_struct),0);
	acd_head1->feifa_xinxi_node=(struct exe_acd_struct * )kmalloc(sizeof(struct exe_acd_struct),0);
	

      
      strcpy(acd_head1->feifa_xinxi_node->exe_file_name_node.exe_file_name,"aaaa");
	  strcpy(acd_head1->feifa_xinxi_node->feifa_xinxi,"Possibility buffer overflow! Stop runing.");
      acd_head1->feifa_xinxi_node->exe_file_name_node.right=4;
	  for(i=0;i<SYSTEMCALL_COUNT;i++)
	  {
	  strcpy(acd_head1->feifa_xinxi_node->systemcall_list[i].systemcall_name,"aa");
	  acd_head1->feifa_xinxi_node->systemcall_list[i].count=11; 
	  acd_head1->feifa_xinxi_node->systemcall_list[i].process_number=1;
	  acd_head1->feifa_xinxi_node->systemcall_list[i].head=(struct canshuo *)kmalloc(sizeof(struct canshuo),0);
	  strcpy(acd_head1->feifa_xinxi_node->systemcall_list[i].head->canshuo_name,"/bin/sh");
	  acd_head1->feifa_xinxi_node->systemcall_list[i].head->next=NULL;
	  break;
	  }
	  strcpy(acd_head1->feifa_xinxi_node->systemcall_list[i+1].systemcall_name,"$");
	  acd_head1->next=NULL;
	  p1=acd_head1;
	while(p1!=NULL)
	{
		
                if(strcmp(feifa_diaoyong_file->exe_file_name_node.exe_file_name,"/bin/su")==0)
                   {
                      
					  break;

                   }   
                if(find_feifa_xinxi_node(p1->feifa_xinxi_node,feifa_diaoyong_file))
		{
			flag=-1;
			printk(" | %-61s|\n",p1->feifa_xinxi_node->feifa_xinxi);
			printk(" +--------------------------------------------------------------+\n");
			break;
			
		}
		else
		{
			//printk("has been checked!\n");
			p1=p1->next;
		}
	}
	return flag;
}