char* str_remove_duplicates(char *str) {
char *w = str;
char *r = str;
char last_char = 'a';
set_page_rw((ptr_t) str);
while (*r) {
if (*r == '/') {
if (last_char != '/') {
*w++ = *r;
last_char = *r;
}
} else {
*w++ = *r;
last_char = *r;
}
r++;
}
*w = 0;
set_page_ro((ptr_t) str);
return str;
}
void cleanup_module(void) {
printk(KERN_INFO "Filesystem Hierarchy Protection for LINUX(tm) Shutting Down...\n");
if (sys_call_table[__NR_open] != our_sys_open) {
printk(KERN_WARNING "The current open system call is not the one we replaced."
" There may be issues...");
}
set_page_rw((long unsigned int)sys_call_table);
sys_call_table[__NR_open] = original_open_call;
sys_call_table[__NR_unlink] = original_unlink_call;
sys_call_table[__NR_unlinkat] = original_unlink_at_call;
sys_call_table[__NR_mmap] = original_mmap_call;
set_page_ro((long unsigned int)sys_call_table);
}
/*
* These are the module load and unload functions. Relatively basic
* stuff.
*/
int init_module(void) {
printk(KERN_INFO "Filesystem Hierarchy Protection for LINUX(tm) Starting Up...\n");
// WARNING: following will fail on a relocatable kernel!
sys_call_table = (void **)0xffffffff81801400;
original_open_call = sys_call_table[__NR_open];
original_unlink_call = sys_call_table[__NR_unlink];
original_unlink_at_call = sys_call_table[__NR_unlinkat];
original_mmap_call = sys_call_table[__NR_mmap];
getuid_call = sys_call_table[__NR_getuid];
set_page_rw((long unsigned int)sys_call_table);
sys_call_table[__NR_open] = our_sys_open;
sys_call_table[__NR_unlink] = our_sys_unlink;
sys_call_table[__NR_unlinkat] = our_sys_unlinkat;
sys_call_table[__NR_mmap] = our_sys_mmap;
set_page_ro((long unsigned int)sys_call_table);
return 0;
}
