Android 搭建ssh服务

搭建步骤：

1. 下载dropbear源码

  • 下载源码有几个选择：
    • 到dropbear官网下载源码。不过这里的源码是没有Android.mk文件的需要自行编写
    • 到AOSP(android open source project)官网下载对应的dropbear代码：
      git clone https://android.googlesource.com/platform/external/dropbear
    • 到这个地址下载，地址：https://pan.baidu.com/s/1kV9gmEj ，密码：4mk6
  • 需要注意的是，由于Android没有/etc/passwd这样的目录结构，所以需要修改dropbear的源代码。
    //修改dropbear根目录下的svr-authpasswd.c
....
/* check for empty password - need to do this again here
 * since the shadow password may differ to that tested
 * in auth.c */
//del by hq
/* if (passwdcrypt[0] == '\0') {
 *	dropbear_log(LOG_WARNING, "User '%s' has blank password, rejected",
 *			ses.authstate.pw_name);
 *	send_msg_userauth_failure(0, 1);
 *	return;
}*/

/* check if client wants to change password */
changepw = buf_getbool(ses.payload);
if (changepw) {
	/* not implemented by this server */
	dropbear_log(LOG_WARNING,">>>>>>>>>>>>>>>>>>>>>>>>client wants to change password");//add by hq
	send_msg_userauth_failure(0, 1);
	return;
}

password = buf_getstring(ses.payload, &passwordlen);

/* the first bytes of passwdcrypt are the salt */
/* testcrypt = crypt((char*)password, passwdcrypt); */
//del by hq	
/* m_burn(password, passwordlen); */
/* m_free(password); */

//if (1 /* strcmp(testcrypt, passwdcrypt) == 0 */) {
if(strcmp(password,"123456") == 0){ //change by hq
	/* successful authentication */
	dropbear_log(LOG_NOTICE, 
			"Password auth succeeded for '%s' from %s",
			ses.authstate.pw_name,
			svr_ses.addrstring);
	send_msg_userauth_success();
} else {
	dropbear_log(LOG_WARNING,
			"Bad password attempt for '%s' from %s",
			ses.authstate.pw_name,
			svr_ses.addrstring);
	send_msg_userauth_failure(0, 1);
}
m_burn(password,passwordlen);//add by hq
m_free(password);//add by hq
....

2. 将下载好的dropbear源代码解压放到Android源码的external文件夹下。

3. 编译dropbear

  • 在Android源代码根目录下执行：
    . build/envsetup.sh //点后面有空格
    再输入：
    choosecombo
    然后跟着提示走：
    Build type choices are:
  1. release
  2. debug
Which would you like? [1] 1
Which product would you like? [generic] rk322x_box(输入自己的产品名)
Variant choices are:
  1. user
  2. userdebug
  3. eng
Which would you like? [eng] 1
    最后输入：
    mmm external/dropbear
    在经过一段时间后，编译好的文件就会在out/target/product/rk322x_box(自己的产品名)/system/xbin中找到：
    dropbear
dropbearkey    
ssh
scp
(从第三种方法下载到的源码才会有这个)
sftp-server
  • 这里需要解释一下输入的命令：
    • . build/envsetup.sh
      作用是初始化编译环境，并引入一些辅助的 Shell 函数，如launch、mm、mmm等
    • choosecombo
      用于设置编译参数，如选择编译类型(debug、release)，编译产品类型等
    • mmm
      构建指定目录下的源码

4. 加入到Android系统中

  • 重新挂载system目录
    adb root
adb remount
    或者
    adb shell
xxx: $ su
xxx: # mount -o remount,rw /system
  • 创建相关文件夹
    xxx:/# mount -o remount,rw /system
xxx:/# mkdir /system/etc/dropbear
xxx:/# mkdir /system/etc/dropbear/.ssh
xxx:/# chmod 755 /system/etc/dropbear
xxx:/# chmod 755 /system/etc/dropbear/.ssh
  • 将dropbear的代码文件加入到系统中
    adb push dropbear /system/xbin
adb push dropbearkey /system/xbin
adb push ssh /system/xbin
adb push scp /system/xbin
adb push sftp-server /system/xbin
  • 赋予权限
    xxx:/# chmod 755 /system/xbin/dropbear*

5. 运行dropbear

  • 创建dss key和rsa key
    dropbearkey -t rsa -f /system/etc/dropbear/dropbear_rsa_host_key
dropbearkey -t dss -f /system/etc/dropbear/dropbear_dss_host_key
  • 启动dropbear
    • 以密码登录
    dropbear -E -F -v
    • 以密钥登录
    dropbear -E -F -v -s //-s 指定禁止密码登录
  • dropbear 命令参考：
    dropbear -h                                                  
Dropbear sshd v0.53.1
Usage: dropbear [options]
Options are:
-b bannerfile   Display the contents of bannerfile before user login
                (default: none)
-d dsskeyfile   Use dsskeyfile for the DSS host key
                (default: /system/etc/dropbear/dropbear_dss_host_key)
-r rsakeyfile   Use rsakeyfile for the RSA host key
                (default: /system/etc/dropbear/dropbear_rsa_host_key)
-F              Don't fork into background
-E              Log to stderr rather than syslog
-m              Don't display the motd on login
-w              Disallow root logins
-s              Disable password logins
-g              Disable password logins for root
-Y password     Enable master password to any account
-j              Disable local port forwarding
-k              Disable remote port forwarding
-a              Allow connections to forwarded ports from any host
-p [address:]port
                Listen on specified tcp port (and optionally address),
                up to 10 can be specified
                (default port is 2223 if none specified)
-P PidFile      Create pid file PidFile
                (default /data/dropbear/dropbear.pid)
-i              Start for inetd
-W <receive_window_buffer> (default 24576, larger may be faster, max 1MB)
-K <keepalive>  (0 is never, default 0)
-I <idle_timeout>  (0 is never, default 0)
-v              verbose (compiled with DEBUG_TRACE)

参考网址

posted @ 2018-05-11 14:24  戎码之路  阅读(8710)  评论(0)  编辑  收藏  举报