当然，如果你正常遍历的话是发现不了虚拟地址的，因为一般使用的读写函数是syscall下的read，这个api呢是读的物理地址
所以第二种则是使用linux的函数“pagemap”将物理地址转换为“缺页地址”，从而去过滤掉“缺页地址”
以下这段就是pagemap实现的整个函数方法
class pagemap
{
private:
int pagemap_fd;
int ipid = -1;
// uint64_t page_size;
public:
bool init(int pid)
{
char pagemap_file[BUFSIZ];
snprintf(pagemap_file, sizeof(pagemap_file), "/proc/%d/pagemap", pid);
// pagemap_fd = open(pagemap_file, O_RDONLY);
pagemap_fd=syscall(__NR_openat,AT_FDCWD,pagemap_file,O_RDONLY,777);
// int fd=syscall(__NR_openat,AT_FDCWD,pagemap_file,O_RDONLY,777);
if (pid < 0) {
return false;
}
if (this->pagemap_fd < 0) {
return 1;
}
if (!f)
{
return false;
}*/
this->ipid=pid;
return true;
}
bool isVirtualAddress(long int address) {
// WARNING: Already detected by tencent
int pageSize = getpagesize();
unsigned long v_pageIndex = address / pageSize; //虚地址页数
unsigned long v_offset = v_pageIndex * sizeof(uint64_t); //计算在/proc/pid/page_map文件中的偏移量
unsigned long page_offset = address % pageSize; //计算虚拟地址在页面中的偏移量
uint64_t item = 0; //存储对应项的值
// long int var[1] = { 0 };
vm_readv(v_offset, &item, sizeof(uint64_t));
// pread(pagemap_fd, &item, sizeof(uint64_t), v_offset);
if ((((uint64_t) 1 << 63) & item) != 0)
{
return false;
}
else
{
return true;
}
return item;
}
void closer()
{
close(this->pagemap_fd);
}
int getDword(long int addr)
{
if (!isVirtualAddress(addr) || addr <= 0)
{
return 0;
}
else
{
long int var[1] = { 0 };
vm_readv(addr, var, 8);
return var[0];
}
}
/* 读浮点型内存 */
float getFloat(long int addr)
{
if (!isVirtualAddress(addr) || addr <= 0)
{
return 0;
}
else
{
float var[1] = { 0 };
vm_readv(addr, var, 8);
return var[0];
}
}
long int getZZ(long int addr)
{
if (!isVirtualAddress(addr) || addr <= 0)
{
return 0;
}
else
{
long int var[1] = { 0 };
vm_readv(addr, var, 8);
// printf（"%lx\n",addr);
return var[0];
}
}
long int getword(long int addr)
{
if (!isVirtualAddress(addr) || addr <= 0)
{
return 0;
}
else
{
long int var[1] = { 0 };
vm_readv(addr, var, 2);
return var[0];
}
}
float WriteFloat(long int addr, float value)
{
vm_writev(addr, &value, 4);
}
int WriteDword(long int addr, int value)
{
vm_writev(addr, &value, 4);
}
};
