pc机取得并修改arm linux IP地址 网关 子网掩码 主机名等信息

（一）获取

1、当pc发送广播，arm linux收到广播信息时，向客户端发送确认信息
客户端可通过socket取出IP地址

2、当pc机发送请求取得上述信息参数时，执行以下系统调用
system("hostname > hostfile");
system("ifconfig > ipfile");
system("route > gwfile");
并将这些文件读取传送到客户端，即pc3、客户端接收到信息后，将其写到一个文件中4、通过文件的特殊标记定位，就可以取得子网掩码 网关 主机名等信息

（二）设置
1、取得设置的主机名、IP、网关、子网掩码等信息
2、将其格式化如下：
对主机名而言：
(1)单独发送到服务器，服务器程序将其写在一个单独文件中，如：/prog/HOSTNAME
(2)修改/etc/init.d/rcS应项为/bin/hostname -F /prog/HOSTNAME 对其他来说：
(1)格式化信息如下：
假若你输入的IP地址为172.29.26.41 子网掩码为255.255.255.0
/sbin/ifconfig eth0 172.29.26.41 netmask 255.255.255.0
(2)假若你输入的默认网关为172.29.26.1
/sbin/route add default gw 172.29.26.1
3、将其替代rcS中的对应项，然后发送到服务器端
4、重新启动服务器，设置生效//客户端获取
void CWireDialog::OnDownload()
{
/*
向服务器发送获取信息,服务器进行系统调用,将信息写在文件中:ip gw
*/

SOCKET sockfd;
SOCKADDR_IN sin,saUdpServ,saClient;
struct TO_SERVER m_msg;
int nSize,nbSize;
int ncount=0;
char *userinfo;
userinfo = new char[2048];
sockfd=socket(PF_INET,SOCK_DGRAM,0);
sin.sin_family = AF_INET;
sin.sin_port = htons(0);
sin.sin_addr.s_addr=htonl(INADDR_ANY);
if(bind( sockfd, (SOCKADDR *)&sin, sizeof(sin))!=0)
{
AfxMessageBox("不能创建网络接口/n");//初始化失败返回-1
closesocket(sockfd);
return;
}
saUdpServ.sin_family = AF_INET;
saUdpServ.sin_addr.s_addr = inet_addr(curIP);
saUdpServ.sin_port = htons (PORT);//发送用的端口，可以根据需要更改 //
nSize = sizeof ( SOCKADDR_IN );
m_msg.MsgID = ID_GETNETINFO;
sendto ( sockfd,(char*)&m_msg, sizeof(m_msg),0,(SOCKADDR *) &saUdpServ,sizeof ( SOCKADDR_IN ));
nSize = sizeof ( SOCKADDR_IN );
while(1)
{
if((nbSize=recvfrom (sockfd,(char*)&m_msg,sizeof(m_msg),0,(SOCKADDR FAR *) &saClient,&nSize))==-1)
{
AfxMessageBox("无法接到日志");
closesocket(sockfd);
return;
}

//正确接收日志文件，写文件
if(m_msg.MsgID == ID_RETNETINFO)
{
//AfxMessageBox("正确接收用户信息");
for(int i=0;i<nbSize-4;i++)
{
userinfo[recv] = m_msg.Msg.usermodify[i];
++recv;
}

else if(m_msg.MsgID = ID_NETINFOOVER)
{
break;
}
}
userinfo[recv] = '/0';
closesocket(sockfd);

CFile userFile;
if(!userFile.Open("netinfo/netinfo",CFile::modeCreate|CFile::modeWrite|CFile::typeBinary))
{
MessageBox("无法打用户信息文件");
return;
}
userFile.Write(userinfo,recv);
userFile.Close();
recv = 0;
delete[] userinfo;

/*
将需要的信息从文件中取出
*/
GetDlgItem(IDC_ID)->SetWindowText(curID);
GetDlgItem(IDC_IP)->SetWindowText(curIP); //IP
/*
NetMask
*/
setmask();
setgateway();
}void CWireDialog::setmask()
{
CFile nFile;
if(!nFile.Open("netinfo/netinfo",CFile::modeRead|CFile::typeBinary))
{
MessageBox("文件打开失败");
return;
}
int nlength = nFile.GetLength();
char *content;
content = new char[nlength]; int nret = nFile.Read(content,nlength);
if(nret < 0)
{
MessageBox("文件读取失败");
return;
}
int pos;
for(int i=0;i<nlength-4;i++)
{
if(content[i] == 'M' && content[i+1] == 'a' && content[i+2] == 's' && content[i+3] == 'k')
{
pos = i;
break;
}
}
if(i == nlength - 5)
{
MessageBox("不能找到子网掩码");
return;
}
pos += 5;
CString str,mask;
while(content[pos] != '/n')
{
str.Format("%c",content[pos]);
mask += str;
pos ++;
}
GetDlgItem(IDC_MASK)->SetWindowText(mask);
nFile.Close();
}void CWireDialog::setgateway()
{
CFile nFile;
if(!nFile.Open("netinfo/netinfo",CFile::modeRead|CFile::typeBinary))
{
MessageBox("文件打开失败");
return;
}
int nlength = nFile.GetLength();
char *con;
con = new char[nlength];

int ret = nFile.Read(con,nlength);
if(ret < 0)
{
MessageBox("文件读取失败");
return;
}
int pos;
for(int i=0;i<nlength-7;i++)
{
if(con[i]=='d'&&con[i+1]=='e'&&con[i+2]=='f'&&con[i+3]=='a'&&con[i+4]=='u'&&con[i+5]=='l'&&con[i+6]=='t')
{
pos = i;
break;
}
}
if(i == nlength-8)
{
MessageBox("不能找到默认网关");
return;
}
pos += 7;
while(con[pos] == ' ')
pos++;
CString str,gw;
while(con[pos] != ' ')
{
str.Format("%c",con[pos]);
gw += str;
pos ++;
}
GetDlgItem(IDC_GATEWAY)->SetWindowText(gw);
nFile.Close();
}//客户端设置
void CWireDialog::OnSet()
{
/*
将信息格式化，然后写入文件
*/
UpdateData(TRUE);
int ret = writeinfo();
if(ret != 0)
{
MessageBox("格式化配置信息失败");
return;
} SOCKET sockfd;
SOCKADDR_IN sin,saUdpServ,saClient;
struct TO_SERVER m_msg;
int nSize,nbSize;
int ncount=0;
sockfd=socket(PF_INET,SOCK_DGRAM,0);
sin.sin_family = AF_INET;
sin.sin_port = htons(0);
sin.sin_addr.s_addr=htonl(INADDR_ANY);
if(bind( sockfd, (SOCKADDR *)&sin, sizeof(sin))!=0)
{
AfxMessageBox("不能创建网络接口/n");//初始化失败返回-1
closesocket(sockfd);
return;
}
saUdpServ.sin_family = AF_INET;
saUdpServ.sin_addr.s_addr = inet_addr(curIP);
saUdpServ.sin_port = htons (PORT);//发送用的端口，可以根据需要更改 /*
发送修改主机名称请求
*/
nSize = sizeof ( SOCKADDR_IN );
m_msg.MsgID = ID_SETHOSTNAME;
strcpy(m_msg.Msg.usermodify,m_strid);
ncount = m_strid.GetLength();
sendto ( sockfd,(char*)&m_msg, ncount+4,0,(SOCKADDR *) &saUdpServ,sizeof ( SOCKADDR_IN ));
nSize = sizeof ( SOCKADDR_IN );
/*
发送修改IP 网关 子网掩码请求
*/
CFile nFile;
if(!nFile.Open("netinfo/rcS",CFile::modeRead|CFile::typeBinary))
{
MessageBox("打开配置文件失败");
return;
}
ncount = nFile.GetLength();
if(!nFile.Read(m_msg.Msg.usermodify,ncount))
{
MessageBox("读取配置文件失败");
return;
}
m_msg.MsgID = ID_SETNETINFO;
sendto ( sockfd,(char*)&m_msg, ncount+4,0,(SOCKADDR *) &saUdpServ,sizeof ( SOCKADDR_IN ));
/*
等待服务器返回标志
*/
if((nbSize=recvfrom (sockfd,(char*)&m_msg,sizeof(m_msg),0,(SOCKADDR FAR *) &saClient,&nSize))==-1)
{
MessageBox("无法接受正确反馈信息");
closesocket(sockfd);
return;
}
if(m_msg.MsgID == ID_SETNETOK)
{
MessageBox("成功修改/n要使修改生效,请重新启动网络");
}
else if(m_msg.MsgID = ID_NETINFOOVER)
{
MessageBox("修改失败");
}
closesocket(sockfd);
return;
}int CWireDialog::writeinfo()
{
UpdateData(TRUE);
CFile nFile;
CString info;
char *buf;
if(!nFile.Open("netinfo/basic",CFile::modeRead|CFile::typeBinary))
{
MessageBox("基本配置文件打开失败");
return -1;
}
int nlength = nFile.GetLength();
buf = new char[nlength];
if(!nFile.Read(buf,nlength))
{
MessageBox("基本配置信息读取失败");
return -1;
}
nFile.Close();
if(!nFile.Open("netinfo/rcS",CFile::modeCreate|CFile::modeWrite|CFile::typeBinary))
{
MessageBox("创建配置文件失败");
return -1;
}
nFile.Write(buf,nlength);
info.Format("/sbin/ifconfig eth0 %s netmask %s/n",m_strip,m_strmask);
nFile.Write(info,info.GetLength());
info.Empty();
info.Format("/sbin/route add default gw %s",m_strgate);
nFile.Write(info,info.GetLength());
return 0;
}
//服务器端设置
if(m_msg.MsgID == ID_SETHOSTNAME)
{
printf("receve quest to modify the host name/n");
int ncount;
if((nfile = open("HOSTNAME",O_WRONLY|O_CREAT|O_TRUNC)) == -1)
{
printf("the host file open error/n");
return ;
}
if((ncount = write(nfile,m_msg.Msg.usermodify,nrsize-4)) != nrsize-4)
{
printf("write host file error");
return ;
}
close(nfile);
break;
}
if(m_msg.MsgID == ID_SETNETINFO)
{
printf("receive quest to modify the net info/n");
int count;
rename("/etc/init.d/rcS","/etc/init.d/rcSold");
printf("rename the rcS file/n");
if((nfile = open("/etc/init.d/rcS",O_WRONLY|O_CREAT|O_TRUNC)) == -1)
{
printf("the rcs file open error/n");
rename("/etc/init.d/rcSold","/etc/init.d/rcS");
printf("rename the rcS file/n");
m_msg.MsgID = ID_SETNETFAIL;
sendto(sockfd,(char*)&m_msg,4,0,(struct sockaddr*)&fromsin,sin_size);
return;
}
if((count = write(nfile,m_msg.Msg.usermodify,nrsize-4)) != nrsize-4)
{
printf("write the rcs file fail/n");
rename("/etc/init.d/rcSold","/etc/init.d/rcS");
printf("rename the rcS file/n");
m_msg.MsgID = ID_SETNETFAIL;
sendto(sockfd,(char*)&m_msg,4,0,(struct sockaddr*)&fromsin,sin_size);
close(nfile);
}
else
{
printf("write the rcs file success/n");
m_msg.MsgID = ID_SETNETOK;
}
sendto(sockfd,(char*)&m_msg,4,0,(struct sockaddr*)&fromsin,sin_size);
close(nfile);
chmod("/etc/init.d/rcS",755);
printf("change the attr of the rcS file/n");
break;
}