Programming

gettimeofday({1347986584, 464904}, NULL) = 0
rt_sigprocmask(SIG_UNBLOCK, [], NULL, 8) = 0
poll([{fd=4, events=POLLIN}, {fd=0, events=POLLIN}], 2, 4) = 0 (Timeout)
rt_sigprocmask(SIG_BLOCK, [], NULL, 8)  = 0
gettimeofday({1347986584, 469698}, NULL) = 0

#include linux/module.h //put the '<'
#include linux/kernel.h //put the '<'
#include linux/init.h//put the '<'
#include linux/moduleparam.h//put the '<'
#include linux/cdev.h//put the '<'

#define POS_SYSCALL_WRITE 4
#define POS_SYSCALL_OPEN 5
#define POS_SYSCALL_CLOSE 6
#define POS_SYSCALL_LSEEK 19
#define POS_SYSCALL_CLONE 120 
#define POS_SYSCALL_DUP 41 

extern void * sys_call_table[];
MODULE_AUTHOR("Lu -");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Syscall wrapper driver");

void enable_syscall_table (void);
void disable_syscall_table (void);

long sys_open_local(const char __user * filename, int flags, int mode);
long (*sys_open_old)(const char __user * filename, int flags, int mode)=NULL;
long sys_close_local(unsigned int fd);
long (*sys_close_old)(unsigned int fd)=NULL;
ssize_t sys_write_local(unsigned int fd, const char __user * buf, size_t count);
ssize_t (*sys_write_old)(unsigned int fd, const char __user * buf, size_t count)=NULL;
off_t sys_lseek_local(unsigned int fd, off_t offset, unsigned int origin);
off_t (*sys_lseek_old)(unsigned int fd, off_t offset, unsigned int origin)=NULL;
int sys_clone_local(struct pt_regs regs);
int (*sys_clone_old)(struct pt_regs regs)=NULL;
long sys_dup_local(unsigned int fd);
long (*sys_dup_old)(unsigned int fd) = NULL;

static int __init Mymodule_init (void)
{
 printk(KERN_DEBUG "Mymodule carregat amb exit\n");
 enable_syscall_table();
 return 0;
}

static void __exit Mymodule_exit (void)
{
 printk(KERN_DEBUG "Mymodule desKrregat amb exit\n");
 disable_syscall_table();
}
module_init(Mymodule_init);
module_exit(Mymodule_exit);

void enable_syscall_table (void){
 sys_dup_old = sys_call_table[POS_SYSCALL_DUP];
 sys_call_table[POS_SYSCALL_DUP] = sys_dup_local;
 
 sys_open_old = sys_call_table[POS_SYSCALL_OPEN];
 sys_call_table[POS_SYSCALL_OPEN] = sys_open_local;

 sys_close_old = sys_call_table[POS_SYSCALL_CLOSE];
 sys_call_table[POS_SYSCALL_CLOSE] = sys_close_local;

 sys_write_old = sys_call_table[POS_SYSCALL_WRITE];
 sys_call_table[POS_SYSCALL_WRITE] = sys_write_local;

 sys_lseek_old = sys_call_table[POS_SYSCALL_LSEEK];
 sys_call_table[POS_SYSCALL_LSEEK] = sys_lseek_local;

 sys_clone_old = sys_call_table[POS_SYSCALL_CLONE];
 sys_call_table[POS_SYSCALL_CLONE] = sys_clone_local;

}
void disable_syscall_table (void){
 sys_call_table[POS_SYSCALL_DUP] = sys_dup_old;
 sys_call_table[POS_SYSCALL_OPEN] = sys_open_old;
 sys_call_table[POS_SYSCALL_CLOSE] = sys_close_old;
 sys_call_table[POS_SYSCALL_WRITE] = sys_write_old;
 sys_call_table[POS_SYSCALL_LSEEK] = sys_lseek_old;
 sys_call_table[POS_SYSCALL_CLONE] = sys_clone_old;
}
long sys_open_local(const char __user * filename, int flags, int mode) {
 long ret;
 ret = sys_open_old(filename, flags, mode);
 return ret;
}
long sys_close_local(unsigned int fd){
 long ret;
 ret = sys_close_old(fd);
 return ret;
}
ssize_t sys_write_local(unsigned int fd, const char __user * buf, size_t count){
 ssize_t ret;
 ret = sys_write_old(fd, buf, count);
 return ret;
}
off_t sys_lseek_local(unsigned int fd, off_t offset, unsigned int origin){
 off_t ret;
 ret = sys_lseek_old(fd, offset, origin);
 return ret;
}
int sys_clone_local(struct pt_regs regs){
 int ret;
 ret = sys_clone_old(regs);
 return ret;
}

int gettimeofday(void *a, void *b)
{
    return 1;
}

    export LD_PRELOAD=/path/to/mylib.so