Function xh_util_get_mem_protect

Bcore/src/main/cpp/xhook/xh_util.c:44–103

#define PAGE_COVER(addr) (PAGE_END(addr) - PAGE_START(addr))

int xh_util_get_mem_protect(uintptr_t addr, size_t len, const char *pathname, unsigned int *prot)
{
    uintptr_t  start_addr = addr;
    uintptr_t  end_addr = addr + len;
    FILE      *fp;
    char       line[512];
    uintptr_t  start, end;
    char       perm[5];
    int        load0 = 1;
    int        found_all = 0;

    *prot = 0;
    
    if(NULL == (fp = fopen("/proc/self/maps", "r"))) return XH_ERRNO_BADMAPS;
    
    while(fgets(line, sizeof(line), fp))
    {
        if(NULL != pathname)
            if(NULL == strstr(line, pathname)) continue;
        
        if(sscanf(line, "%"PRIxPTR"-%"PRIxPTR" %4s ", &start, &end, perm) != 3) continue;
        
        if(perm[3] != 'p') continue;
        
        if(start_addr >= start && start_addr < end)
        {
            if(load0)
            {
                //first load segment
                if(perm[0] == 'r') *prot |= PROT_READ;
                if(perm[1] == 'w') *prot |= PROT_WRITE;
                if(perm[2] == 'x') *prot |= PROT_EXEC;
                load0 = 0;
            }
            else
            {
                //others
                if(perm[0] != 'r') *prot &= ~PROT_READ;
                if(perm[1] != 'w') *prot &= ~PROT_WRITE;
                if(perm[2] != 'x') *prot &= ~PROT_EXEC;
            }

            if(end_addr <= end)
            {
                found_all = 1;
                break; //finished
            }
            else
            {
                start_addr = end; //try to find the next load segment
            }
        }
    }
    
    fclose(fp);

    if(!found_all) return XH_ERRNO_SEGVERR;