如何固定以太口地址为指定IP？

rxw的RK3568的evb1公板，有2个以太口，

默认UI界面只能配置eth0，无法配置eth1，

实际应用中，有时需要一旦有网线插入，就需要该地址设置为指定IP地址。

本文介绍2个最简单的方法实现固定IP。

一、通过修改ipconfig.txt

安卓设备以太口的配置信息保存在以下文件中：

/data/misc/ethernet/ipconfig.txt

该文件是二进制文件，而且默认只有eth0的配置信息，一口君通过一些特殊方法，生成了包含eth0、eth1的两个网口配置的配置文件，

并且rxw原厂的ui界面可以识别该配置文件。

配置文件用16进制格式打开内容如下：

0000000000000003000C697041737369676E6D65......ipAssignme
000000106E740006535441544943000B6C696E6Bnt..STATIC..link
0000002041646472657373000D3139322E313638Address..192.168
000000302E34302E333400000018000767617465.40.34......gate
000000407761790000000000000001000C313932way..........192
000000502E3136382E34302E310003646E730007.168.40.1..dns..
00000060302E302E302E300003646E730007302E0.0.0.0..dns..0.
00000070302E302E30000D70726F7879536574740.0.0..proxySett
00000080696E677300044E4F4E45000269640004ings..NONE..id..
00000090657468300003656F73000C6970417373eth0..eos..ipAss
000000A069676E6D656E74000653544154494300ignment..STATIC.
000000B00B6C696E6B41646472657373000D3139.linkAddress..19
000000C0322E3136382E322E31323500000018002.168.2.125.....
000000D007676174657761790000000000000001.gateway........
000000E0000B3139322E3136382E322E31000364..192.168.2.1..d
000000F06E730007302E302E302E300003646E73ns..0.0.0.0..dns
000001000007302E302E302E30000D70726F7879..0.0.0.0..proxy
0000011053657474696E677300044E4F4E450002Settings..NONE..
0000012069640004657468310003656F73------id..eth1..eos

用 ascii格式打开如下【因为是二进制文件，会有部分内容是乱码】：

ipAssignmentSTATIClinkAddress
192.168.40.34gateway192.168.40.1dns0.0.0.0dns0.0.0.0
proxySettingsNONEideth0eosipAssignmentSTATIClinkAddress
192.168.2.125gateway192.168.2.1dns0.0.0.0dns0.0.0.0
proxySettingsNONEideth1eos

总结一下，主要配置信息如下：

|网口|ip|网关|
|-----------------------------------------|
|eth0|192.168.40.34|192.168.40.1|
|eth1|192.168.2.125|192.168.2.1|

将该文件push进开发板，重启即可

adbroot
adbremount
adbpull/data/misc/ethernet/ipconfig.txt

这样只要eth1对应的以太口up，就会自动设置ip地址192.168.2.125

同时并不影响UI配置eth0接口

“

注意：

这种方法仅在rxw3568+android11上测试通过，其他平台或者android版本没有测试。

”

二、通过开源项目ifplugd

除了第一种种方法还可以通过一个开源的项目ifplugd来实现。

通过ifplugd工具监听网口热插拔信息，然后执行指定脚本，将配置命令存放在脚本中即可。

ifplugd的移植需要用到libdaemon库，该库主要提供守护进程以及log接口功能。

1. 移植步骤

1）准备文件：

libdaemon-0.14.tar.gz
ifplugd-0.14.tar.gz

后台回复：eth，既可以获取

“

没有采用最新的libdaemon、ifplugd，会有版本兼容问题

”

本实例基于ndk编译器编译，

为了方便起见，我把libdaemon、ifplugd源文件全部拷贝到ndk实例工程下，libdaemon的头文件，拷贝了2次，

方便c文件包含。

.....src-ifplugd$tree./
./
├──Application.mk
├──daemon.h
├──dexec.c
├──dexec.h
├──dfork.c
├──dfork.h
├──dlog.c
├──dlog.h
├──dnonblock.c
├──dnonblock.h
├──dpid.c
├──dpid.h
├──dsignal.c
├──dsignal.h
├──ethtool-kernel.h
├──ethtool-local.h
├──ifplugd.c
├──ifstatus.c
├──include
├──interface.c
├──interface.h
├──libdaemon
│├──daemon.h
│├──dexec.h
│├──dfork.h
│├──dlog.h
│├──dnonblock.h
│├──dpid.h
│└──dsignal.h
├──svn-revision.h
└──YROS.mk

2directories,29files

2）修改配置文件

编译描述信息位于文件YROS.mk中，

【读者根据自己工程，文件会有所不同】

YROS.mk修改如下：

LOCAL_PATH:=$(callmy-dir)

include$(CLEAR_VARS)
LOCAL_SRC_FILES:=
ifplugd.cinterface.cdexec.cdfork.cdlog.cdnonblock.cdpid.cdsignal.c


LOCAL_SHARED_LIBRARIES:=

LOCAL_MODULE_TAGS:=optional
LOCAL_CLANG:=true

LOCAL_MODULE:=ethcheckd

include$(BUILD_EXECUTABLE)

3）编译

编译错误1

λbuild.bat

ndk-build.cmd
[armeabi-v7a]Compilethumb:ifplugd<= ifplugd.c                                                                                 
src/ifplugd.c13: error: use of undeclared identifier 'SYSCONFDIR'                                                               
char *run = SYSCONFDIR"/ifplugd/ifplugd.action";                                                                                    
            ^                                                                                                                       
src/ifplugd.c23: error: expected ';' after top level declarator                                                                 
char *run = SYSCONFDIR"/ifplugd/ifplugd.action";                                                                                    
                      ^                                                                                                             
                      ;                                                                                                             
src/ifplugd.c18: warning: multiple unsequenced modifications to 'sigfd' [-Wunsequenced]                                        
    FD_SET(sigfd = daemon_signal_fd(), &rfds);                                                                                      
                 ^                                                                                                                  
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h50: note: expanded from macro 'FD_SET'                            
#define FD_SET(fd, set) (__FDS_BITS(set)[__FDELT(fd)] |= __FDMASK(fd))                                                              
                                                 ^                ~~                                                                
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h23: note: expanded from macro '__FDELT'                           
#define __FDELT(fd) ((fd) / NFDBITS)                                                                                                
                      ^                                                                                                             
src/ifplugd.c36: error: expected ')'                                                                                           
    daemon_log(LOG_INFO, "ifplugd "VERSION" successfully initialized, link beat %sdetected.", status == IFSTATUS_UP ? "" : "not "); 
                                   ^                                                                                                
src/ifplugd.c15: note: to match this '('                                                                                       
    daemon_log(LOG_INFO, "ifplugd "VERSION" successfully initialized, link beat %sdetected.", status == IFSTATUS_UP ? "" : "not "); 
              ^                                                                                                                     
src/ifplugd.c18: warning: multiple unsequenced modifications to 'sigfd' [-Wunsequenced]                                        
    FD_SET(sigfd = daemon_signal_fd(), &rfds);                                                                                      
                 ^                                                                                                                  
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h50: note: expanded from macro 'FD_SET'                            
#define FD_SET(fd, set) (__FDS_BITS(set)[__FDELT(fd)] |= __FDMASK(fd))                                                              
                                                 ^                ~~                                                                
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h23: note: expanded from macro '__FDELT'                           
#define __FDELT(fd) ((fd) / NFDBITS)                                                                                                
                      ^                                                                                                             
src/ifplugd.c26: error: expected ')'                                                                                           
        printf("ifplugd "VERSION" (SVN: "SVN_REVISION")
");                                                                        
                         ^                                                                                                          
src/ifplugd.c15: note: to match this '('                                                                                       
        printf("ifplugd "VERSION" (SVN: "SVN_REVISION")
");                                                                        
              ^                                                                                                                     
2 warnings and 4 errors generated.                                                                                                  
make: *** [obj/local/armeabi-v7a/objs/ifplugd/ifplugd.o] Error 1                                                                    

请添加图片描述

修改文件ifplugd.c

59#defineVARRUN"/system"
63#defineSYSCONFDIR""
64#defineVERSION"yikoulinux"

编译错误2

λbuild.bat

ndk-build.cmd
[armeabi-v7a]Compilethumb:ifplugd<= dexec.c
[armeabi-v7a] Compile thumb  : ifplugd <= dfork.c
[armeabi-v7a] Compile thumb  : ifplugd <= dlog.c
[armeabi-v7a] Compile thumb  : ifplugd <= dnonblock.c
[armeabi-v7a] Compile thumb  : ifplugd <= dpid.c
src/dpid.c43: error: use of undeclared identifier 'LOCALSTATEDIR'
    snprintf(fn, sizeof(fn), "%s/%s.pid", VARRUN, daemon_pid_file_ident ? daemon_pid_file_ident : "unknown");
                                          ^
src/dpid.c16: note: expanded from macro 'VARRUN'
#define VARRUN LOCALSTATEDIR "/run"
               ^
1 error generated.
make: *** [obj/local/armeabi-v7a/objs/ifplugd/dpid.o] Error 1

修改文件dpid.c

50#defineLOCALSTATEDIR

4） 编译成功

编译成功log如下：

H:compileforandroid
λbuild.bat

ndk-build.cmd
[armeabi-v7a]Compilethumb:ifplugd<= ifplugd.c                                                                      
src/ifplugd.c53: warning: missing sentinel in function call [-Wsentinel]                                            
        execl(run, run, interface, arg, extra_arg, 0);                                                                   
                                                    ^                                                                    
                                                    , NULL                                                               
H:/yros-ndk-windows/build//../sysroot/usr/includeunistd.h5: note: function has been explicitly marked sentinel here
int execl(const char* __path, const char* __arg0, ...) __attribute__((__sentinel__));                                    
    ^                                                                                                                    
src/ifplugd.c18: warning: multiple unsequenced modifications to 'sigfd' [-Wunsequenced]                             
    FD_SET(sigfd = daemon_signal_fd(), &rfds);                                                                           
                 ^                                                                                                       
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h50: note: expanded from macro 'FD_SET'                 
#define FD_SET(fd, set) (__FDS_BITS(set)[__FDELT(fd)] |= __FDMASK(fd))                                                   
                                                 ^                ~~                                                     
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h23: note: expanded from macro '__FDELT'                
#define __FDELT(fd) ((fd) / NFDBITS)                                                                                     
                      ^                                                                                                  
src/ifplugd.c18: warning: multiple unsequenced modifications to 'sigfd' [-Wunsequenced]                             
    FD_SET(sigfd = daemon_signal_fd(), &rfds);                                                                           
                 ^                                                                                                       
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h50: note: expanded from macro 'FD_SET'                 
#define FD_SET(fd, set) (__FDS_BITS(set)[__FDELT(fd)] |= __FDMASK(fd))                                                   
                                                 ^                ~~                                                     
H:/yros-ndk-windows/build//../sysroot/usr/includesys/select.h23: note: expanded from macro '__FDELT'                
#define __FDELT(fd) ((fd) / NFDBITS)                                                                                     
                      ^                                                                                                  
3 warnings generated.                                                                                                    
[armeabi-v7a] Compile thumb  : ifplugd <= interface.c                                                                    
[armeabi-v7a] Compile thumb  : ifplugd <= dexec.c                                                                        
[armeabi-v7a] Compile thumb  : ifplugd <= dfork.c                                                                        
[armeabi-v7a] Compile thumb  : ifplugd <= dlog.c                                                                         
[armeabi-v7a] Compile thumb  : ifplugd <= dnonblock.c                                                                    
[armeabi-v7a] Compile thumb  : ifplugd <= dpid.c                                                                         
[armeabi-v7a] Compile thumb  : ifplugd <= dsignal.c                                                                      
[armeabi-v7a] Executable     : ifplugd                                                                                   
[armeabi-v7a] Install        : ifplugd =>libs/armeabi-v7a/ifplugd

在这里插入图片描述

程序位置如下：

libsarmeabi-v7aifplugd

测试

1. 查看ifplugd参数

ifplugd-h

rk3568_r:/#ifplugd-h
ifplugd[options]
-a--no-autoDonotenableinterfaceautomatically(off)
-n--no-daemonDonotdaemonize(fordebugging)(off)
-s--no-syslogDonotusesyslog,usestderrinstead(fordebugging)(off)
-b--no-beepDonotbeep(off)
-f--ignore-failIgnoredetectionfailure,retryinstead(failureistreatedasDOWN)(off)
-F--ignore-fail-positiveIgnoredetectionfailure,retryinstead(failureistreatedasUP)(off)
-i--iface=IFACESpecifyethernetinterface(eth0)
-r--run=EXECSpecifyprogramtoexecute(/ifplugd/ifplugd.action)
-I--ignore-retvalDon'texitonnonzeroreturnvalueofprogramexecuted(off)
-t--poll-time=SECSSpecifypolltimeinseconds(1)
-u--delay-up=SECSSpecifydelayforconfiguringinterface(0)
-d--delay-down=SECSSpecifydelayfordeconfiguringinterface(5)
-m--api-mode=MODEForceAPImode(mii,priv,ethtool,wlan,auto)(auto)
-q--no-shutdownDon'trunscriptondaemonquit(off)
-w--wait-on-forkWaituntildaemonforkfinished(off)
-x--extra-argSpecifyanextraargumentforactionscript
-h--helpShowthishelp
-k--killKillarunningdaemon
-c--check-runningCheckifadaemoniscurrentlyrunning
-v--versionShowversion
-S--suspendSuspendrunningdaemon
-R--resumeResumerunningdaemon
-z--infoWritestatusofrunningdaemontosyslog

2. 增加脚本if.sh

当网口eth1 up后，ifplugd会执行如下命令【下面动作由ifplugd自动执行】：

/system/if.sheth1up

根据参数顺序，编写脚本if.sh如下：

#!/bin/bash

IPADDR=192.168.40.8
ETHPORT=eth1
echo"danielpengset"$ETHPORT$IPADDR
echo$#
echo$0
echo$1
echo$2
if[$#-eq2];then
if[$1=$ETHPORT];then
echo$ETHPORT
if[$2="up"];then
ifconfig$ETHPORT$IPADDR
sleep1
ipruleaddfromalllookupmainpref9000
sleep1
echo1>/proc/sys/net/ipv4/ip_forward
iptables-F
echo"set"$ETHPORT"done"
elif[$2="down"];then
echo"down"
elif[$2="disable"];then
echo"disable"
elif[$2="error"];then
echo"error"
fi
fi
fi

功能：

网口eth1 up后，设置该网口地址为IPADDR，即：192.168.40.8

读者可以根据自己的需要编写相应的脚本。

3. 运行ifplugd

ifplugd监听网口eth1并且执行后面的脚本文件

在板子上输入以下命令：

ifplugd-ieth1-r"sh/system/if.sh"

查看该守护进程：

H:compileforandroid
λadbshell
rk3568_r:/#ifplugd-ieth1-r"sh/system/if.sh"
rk3568_r:/#ps-ef|grepif
wifi280100952?0000android.hardware.wifi@1.0-service
wifi385100953?0000wificond
root1826101006?0000ifplugd-ieth1-rsh/system/if.sh
root1834181921017pts/00000grepif

一旦网口插入网线后，地址就会被自动设置。

补充

ifplugd的确可以实现监测网卡的状态，并执行相应脚本，

但是有个前提，就是网口已经注册到系统中，即用ifconfig -a能查看到

如何是usb网口这种设备，在插入usb口之后网口设备才会注册，

那么这种情况下，要想设置usb网卡，那么就就需要修改ifplugd程序。

下文，给大家讲解如何自己实现一个简单的网口检测并设置ip的小程序。

审核编辑：汤梓红