/*
参考 http://bbs.csdn.net/topics/230001156 原文为win32版本
稍有改动，以适应mac与linux系统
*/
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/proc.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <netdb.h> // gethostbyname
typedef int SOCKET;
typedef struct icmp_hdr
{
unsigned char icmp_type; // 消息类型
unsigned char icmp_code; // 代码
unsigned short icmp_checksum; // 校验和
// 下面是回显头
unsigned short icmp_id; // 用来惟一标识此请求的ID号
unsigned short icmp_sequence; // 序列号
unsigned long icmp_timestamp; // 时间戳
} ICMP_HDR, *PICMP_HDR;
typedef struct _IPHeader // 20字节的IP头
{
uint8_t iphVerLen; // 版本号和头长度（各占4位）
uint8_t ipTOS; // 服务类型
uint16_t ipLength; // 封包总长度，即整个IP报的长度
uint16_t ipID; // 封包标识，惟一标识发送的每一个数据报
uint16_t ipFlags; // 标志
uint8_t ipTTL; // 生存时间，就是TTL
uint8_t ipProtocol; // 协议，可能是TCP、UDP、ICMP等
uint16_t ipChecksum; // 校验和
uint32_t ipSource; // 源IP地址
uint32_t ipDestination; // 目标IP地址
} IPHeader, *PIPHeader;
uint16_t checksum(uint16_t* buff, int size);
bool SetTimeout(SOCKET s, int nTime, bool bRecv = TRUE);
inline uint32_t GetIpByName(const char * name)
{
hostent* pHostent = gethostbyname(name);
if(pHostent == nullptr) return INADDR_NONE;
uint32_t host = *(uint32_t*)pHostent->h_addr_list[0];
return host;
}
int main(int args, const char ** argv)
{
// 目的IP地址，即要Ping的IP地址
const char * szDestIp = (args > 1)?argv[1]:"127.0.0.1";
auto ip = inet_addr(szDestIp);
if((int)ip == -1) ip = GetIpByName(szDestIp); // nds
if((int)ip == -1)
{
printf("invalid ip address:%s\n", szDestIp);
return -1;
}
uint16_t pID = (uint16_t)::time(0);
printf("ping %s\n", szDestIp);
// 创建原始套节字
SOCKET sRaw = ::socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
if(sRaw == -1)
{
auto eno = errno;
if(eno == 1)
{
// 必须使用sudo才能建立Raw socket
printf("Operation not permitted!\n");
}
else
{
printf("Cannot create socket! Error %d", eno);
}
return -1;
}
// 设置接收超时
if(!SetTimeout(sRaw, 1000, TRUE))
{
printf("Cannot set timeout!\n");
}
// 设置目的地址
sockaddr_in dest;
dest.sin_family = AF_INET;
dest.sin_port = htons(0);
dest.sin_addr.s_addr = ip;
// 创建ICMP封包
char buff[sizeof(ICMP_HDR) + 32];
ICMP_HDR* pIcmp = (ICMP_HDR*)buff;
// 填写ICMP封包数据
pIcmp->icmp_type = 8; // 请求一个ICMP回显
pIcmp->icmp_code = 0;
pIcmp->icmp_id = (uint16_t)pID;
pIcmp->icmp_checksum = 0;
pIcmp->icmp_sequence = 0;
// 填充数据部分，可以为任意
memset(&buff[sizeof(ICMP_HDR)], 'E', 32);
// 开始发送和接收ICMP封包
uint16_t nSeq = 0;
char recvBuf[1024];
sockaddr_in from;
socklen_t nLen = sizeof(from);
while(TRUE)
{
static int nCount = 0;
long nRet;
if(nCount++ == 4)
break;
pIcmp->icmp_checksum = 0;
pIcmp->icmp_timestamp = ::clock();
pIcmp->icmp_sequence = nSeq++;
pIcmp->icmp_checksum = checksum((uint16_t*)buff, sizeof(ICMP_HDR) + 32);
nRet = (long)::sendto(sRaw, buff, sizeof(ICMP_HDR) + 32,
0, (sockaddr *)&dest, sizeof(dest));
if(nRet == -1)
{
printf(" sendto() failed: %d \n", errno);
return -1;
}
nRet = (long)::recvfrom(sRaw, recvBuf, 1024, 0, (sockaddr*)&from, &nLen);
if(nRet == -1)
{
printf(" recvfrom() failed: %d\n", errno);
return -1;
}
// 下面开始解析接收到的ICMP封包
auto nTick = ::clock();
if(nRet < sizeof(IPHeader) + sizeof(ICMP_HDR))
{
printf(" Too few bytes from %s \n", ::inet_ntoa(from.sin_addr));
}
// 接收到的数据中包含IP头，IP头大小为20个字节，所以加20得到ICMP头
ICMP_HDR* pRecvIcmp = (ICMP_HDR*)(recvBuf + 20); // (ICMP_HDR*)(recvBuf + sizeof(IPHeader));
#if 0 // IP头解析
IPHeader * header = (IPHeader*)recvBuf;
struct in_addr a;
a.s_addr = header->ipSource;
printf("source ip %s\n", inet_ntoa(a));
a.s_addr = header->ipDestination;
printf("dest ip %s\n", inet_ntoa(a));
#endif
if(pRecvIcmp->icmp_type != 0) // 回显
{
printf(" nonecho type %d recvd \n", pRecvIcmp->icmp_type);
return -1;
}
if(pRecvIcmp->icmp_id != pID)
{
printf(" someone else's packet! \n");
return -1;
}
printf(" %d bytes from %s:", (int)nRet, inet_ntoa(from.sin_addr));
printf(" icmp_seq = %d. ", pRecvIcmp->icmp_sequence);
printf(" time: %d ms", (int)nTick - (int)pRecvIcmp->icmp_timestamp);
printf(" \n");
}
return 0;
}
uint16_t checksum(uint16_t* buff, int size)
{
unsigned long cksum = 0;
while(size>1)
{
cksum += *buff++;
size -= sizeof(uint16_t);
}
// 是奇数
if(size)
{
cksum += *(uint8_t*)buff;
}
// 将32位的chsum高16位和低16位相加，然后取反
while(cksum >> 16)
cksum = (cksum >> 16) + (cksum & 0xffff);
return (uint16_t)(~cksum);
}
bool SetTimeout(SOCKET s, int nTime, bool bRecv)
{
int ret = ::setsockopt(s, SOL_SOCKET,
bRecv ? SO_RCVTIMEO : SO_SNDTIMEO, (char*)&nTime, sizeof(nTime));
return ret != -1;
}