Blog @ Blog

當(dāng)華美的葉片落盡，生命的脈絡(luò)才歷歷可見。－－聶魯達

導(dǎo)航

公告

留言簿(20)

隨筆分類(156)

文章分類(1)

隨筆檔案(198)

文章檔案(2)

相冊

Meet or get-together

閱讀排行榜

評論排行榜

常用鏈接

統(tǒng)計

隨筆 - 198
文章 - 2
評論 - 156
引用 - 0

積分與排名

積分 - 663219
排名 - 25

BBS

Sohu Club

Blog

Web

CSDN
VC KBase

結(jié)構(gòu)體對齊問題

//定義的結(jié)構(gòu)體如下：

typedef struct arp_header{

//-----------------------DLC Header----------------------------------------

unsigned char DesMAC[6]; //目標(biāo)MAC

unsigned char SrcMAC[6]; //源MAC

unsigned short EtherType; //EtherType默認為0x0806是ARP幀的類型值

//-----------------------ARP Frame-----------------------------------------

unsigned short HW_Type; //硬件類型

unsigned short Prot_Type; //上層協(xié)議類型

unsigned char HW_Addr_Len; //MAC地址長度

unsigned char Prot_Addr_Len; //IP地址類型

unsigned short Opcode; //操作碼 0x01表示ARP請求包 0x02表示RARP應(yīng)答包

unsigned char Send_MAC_Addr[6]; //發(fā)送方MAC

unsigned long Send_IP_Addr; //發(fā)送方IP

unsigned char Targ_MAC_Addr[6];//接收方MAC

unsigned long arg_IP_Addr; //接受方IP

unsigned char padding[18]; //填充數(shù)據(jù)

}ARPHEADER,*PARPHEADER;

填充：

m_ARPHdr = new ARPHEADER;

//--------------------------------填充ARP頭--------------------------------

m_ARPHdr->DesMAC[0] = 0Xff;

m_ARPHdr->DesMAC[1] = 0Xff;

m_ARPHdr->DesMAC[2] = 0Xff;

m_ARPHdr->DesMAC[3] = 0Xff;

m_ARPHdr->DesMAC[4] = 0Xff;

m_ARPHdr->DesMAC[5] = 0Xff;

m_ARPHdr->SrcMAC[0] = 0X00;

m_ARPHdr->SrcMAC[1] = 0X08;

m_ARPHdr->SrcMAC[2] = 0X02;

m_ARPHdr->SrcMAC[3] = 0XDB;

m_ARPHdr->SrcMAC[4] = 0X3B;

m_ARPHdr->SrcMAC[5] = 0X95;

m_ARPHdr->EtherType = 0X0608;

// m_ARPHdr->

m_ARPHdr->HW_Type =0X0100; //硬件類型

m_ARPHdr->Prot_Type = 0X0008; //上層協(xié)議類型

m_ARPHdr->HW_Addr_Len = 0X06; //MAC地址長度

m_ARPHdr->Prot_Addr_Len =0X04; //IP地址類型

m_ARPHdr->Opcode = 0X0100; //操作碼 0x01表示ARP請求包 0x02表示RARP應(yīng)答包

// m_ARPHdr->Send_MAC_Addr[6]; //發(fā)送方MAC

m_ARPHdr->Send_MAC_Addr[0] = 0X00;

m_ARPHdr->Send_MAC_Addr[1] = 0X08;

m_ARPHdr->Send_MAC_Addr[2] = 0X02;

m_ARPHdr->Send_MAC_Addr[3] = 0XDB;

m_ARPHdr->Send_MAC_Addr[4] = 0X3B;

m_ARPHdr->Send_MAC_Addr[5] = 0X95;

m_ARPHdr->Send_IP_Addr = inet_addr("192.168.11.162"); //發(fā)送方IP

// m_ARPHdr->Targ_MAC_Addr[6];//接收方MAC

m_ARPHdr->Targ_MAC_Addr[0] = 0X00;

m_ARPHdr->Targ_MAC_Addr[1] = 0X00;

m_ARPHdr->Targ_MAC_Addr[2] = 0X00;

m_ARPHdr->Targ_MAC_Addr[3] = 0X00;

m_ARPHdr->Targ_MAC_Addr[4] = 0X00;

m_ARPHdr->Targ_MAC_Addr[5] = 0X00;

m_ARPHdr->arg_IP_Addr = inet_addr("192.168.11.154"); //接受方IP

//m_ARPHdr->padding[18] ; //填充數(shù)據(jù)

memset(&(m_ARPHdr->padding[0]),0,18);

//填充后m_ARPHdr 值如下：

//FF FF FF FF FF FF 00 08 02 DB 3B 95 08 06 00 01 08 00 06 04 00 01 00 08 02 DB 3B 95 C0 A8 0B A2 00 00 00 00 00 00 C0 A8 0B 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

//轉(zhuǎn)換：

u_char* packet = (u_char*)m_ARPHdr;

//轉(zhuǎn)換后packet等于

//FF FF FF FF FF FF 00 08 02 DB 3B 95 08 06 00 01 08 00 06 04 00 01 00 08 02 DB 3B 95 C0 A8 0B A2 00 00 00 00 00 00 CD CD C0 A8 0B 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

//而且還有一個問題：

int n = sizeof(ARPHEADER);

//等于64；而不是60

為什么C0 A8 0B 02前怎么不是CD CD

posted on 2008-05-25 21:50 isabc 閱讀(627) 評論(1) 編輯收藏引用所屬分類: BUG分析

#pragma pack(push)
#pragma pack(1)
typedef struct arp_header{
//-----------------------DLC Header----------------------------------------
unsigned char DesMAC[6]; //目標(biāo)MAC
unsigned char SrcMAC[6]; //源MAC
unsigned short EtherType; //EtherType默認為0x0806是ARP幀的類型值
//-----------------------ARP Frame-----------------------------------------
unsigned short HW_Type; //硬件類型
unsigned short Prot_Type; //上層協(xié)議類型
unsigned char HW_Addr_Len; //MAC地址長度
unsigned char Prot_Addr_Len; //IP地址類型
unsigned short Opcode; //操作碼 0x01表示ARP請求包 0x02表示RARP應(yīng)答包

unsigned char Send_MAC_Addr[6]; //發(fā)送方MAC
unsigned long Send_IP_Addr; //發(fā)送方IP
unsigned char Targ_MAC_Addr[6];//接收方MAC
unsigned long arg_IP_Addr; //接受方IP
unsigned char padding[18]; //填充數(shù)據(jù)
}ARPHEADER,*PARPHEADER;
#pragma pack(pop)
回復(fù) 更多評論

刷新評論列表

只有注冊用戶登錄后才能發(fā)表評論。


相關(guān)文章: VS2005環(huán)境ATL工程報錯：error C2065: “_Module”: 未聲明的標(biāo)識符 error LNK2001: unresolved external symbol _main解決辦法結(jié)構(gòu)體對齊問題 strcpy()賦值和直接賦值的區(qū)別 sizeof求長度的錯誤用法。如何處理這個字符串str=“11,陸亞訊,19200,FFFF,1,0,0,0,0,0,4,3” Unhandled exception in EastR.exe (MFC42D.DLL) :0xC0000005;Access Violation

網(wǎng)站導(dǎo)航: 博客園 IT新聞 BlogJava 博問 Chat2DB 管理

# re: 結(jié)構(gòu)體對齊問題 2008-05-25 21:51 isabc

青青草原综合久久大伊人导航_色综合久久天天综合_日日噜噜夜夜狠狠久久丁香五月_热久久这里只有精品