dropbear交叉编译移植记录
dropbear交叉编译移植记录
dropbear 默认支持 zlib（用于压缩），如果特殊场景下需要关闭，可以在执行configure的时候加上 --disable-zlib参数
zlib交叉编译
- 下载解压zlib
wget https://zlib.net/current/zlib.tar.gz tar-zxf zlib.tar.gz- 编译
mkdir install_zlib#创建安装目录export PATH=$PATH:/home/LRX/tools/toolchains/gcc-linaro-11.3.1-2022.06-x86_64_arm-linux-gnueabihf/bin#导出编译链环境变量CC=arm-linux-gnueabihf-gcc \ AR=arm-linux-gnueabihf-ar \./configure--prefix=/home/LRX/libraries/zlib-1.3.2/install_zlib make make installdropbear交叉编译
- 下载解压dropbear
wget https://matt.ucc.asn.au/dropbear/releases/dropbear-2022.83.tar.bz2 tar-jxvf dropbear-2022.83.tar.bz2- 编译
CPPFLAGS="-I/home/LRX/libraries/zlib-1.3.2/install_zlib/include"LDFLAGS="-L/home/LRX/libraries/zlib-1.3.2/install_zlib/lib"./configure--prefix=/home/LRX/libraries/dropbear-2022.83/install_dropbear--host=arm-linux-gnueabihf CC=/home/LRX/tools/toolchains/gcc-linaro-11.3.1-2022.06-x86_64_arm-linux-gnueabihf/bin/arm-linux-gnueabihf-gcc make make install make scpcpscp install_dropbear/bin移植到板卡
修改原有rootfs
- 移植dropbear
cd install_dropbearcpsbin/dropbear ${YOUR_ROOTFS_PATH}/mini_rootfs/usr/sbincpbin/*${YOUR_ROOTFS_PATH}/mini_rootfs/usr/bin- 移植libz库
cplibz.so.1.3.2 ${YOUR_ROOTFS_PATH}/mini_rootfs/lib ln-s/lib/libz.so.1.3.2/lib/libz.so.1- 在板卡上执行
mkdir-p/etc/dropbear cd/etc/dropbear dropbearkey-t rsa-f/etc/dropbear/dropbear_rsa_host_key dropbearkey-t dss-f dropbear_dss_host_key- dropbear自动开机配置
我的rootfs是busybox编译出来的，需要增加自启动脚本，步骤如下：
cd/etc/init.d/ touch S99dropbear#!/bin/shDROPBEAR=/usr/sbin/dropbear DROPBEARKEY=/usr/bin/dropbearkey PIDFILE=/var/run/dropbear.pid KEY_DIR=/etc/dropbear RSA_KEY=$KEY_DIR/dropbear_rsa_host_keystart(){echo"Starting dropbear..."mkdir-p$KEY_DIRmkdir-p/var/run# 生成 RSA keyif[!-f$RSA_KEY];thenecho"Generating RSA key..."$DROPBEARKEY-t rsa-f$RSA_KEYfi# 启动$DROPBEAR-R-p 22-P$PIDFILEecho"dropbear started"}stop(){echo"Stopping dropbear..."if[-f$PIDFILE];thenkill$(cat$PIDFILE)rm-f$PIDFILEelsekillall dropbear 2>/dev/null fiecho"dropbear stopped"}restart(){stopsleep1start}status(){ifpidof dropbear >/dev/null;thenecho"dropbear is running"elseecho"dropbear is stopped"fi}case"$1"instart)start;;stop)stop;;restart)restart;;status)status;;*)echo"Usage:$0{start|stop|restart|status}";;esacexit0执行/etc/init.d/S99dropbear start临时测试
至此dropbear移植完成
- 移植过程遇到问题及临时解决方案
（1） zlib编译CC环境变量没设置成功导致使用本机gcc编译
避坑建议：zlib 的 configure 不支持 CC=xxx 写在后面，必须写在前面
（2）devpts 未自动挂载导致无法通过/dev/pts文件节点访问终端设备
# dropbear -F -R -p 22 -d /etc/dropbear/dropbear_dss_host_key -r /etc/dropbear/dropbear_rsa_host_keyJan 1 00:26:21 smios-initramfs authpriv.info dropbear[196]: Not backgrounding Jan 1 00:26:25 smios-initramfs authpriv.info dropbear[197]: Child connectionfrom192.168.1.98:65234 Jan 1 00:26:27 smios-initramfs authpriv.notice dropbear[197]: Password auth succeededfor'root'from192.168.1.98:65234 Jan 1 00:26:27 smios-initramfs authpriv.info dropbear[198]: Child connectionfrom192.168.1.98:65237 Jan 1 00:26:27 smios-initramfs authpriv.warn dropbear[197]: pty_allocate: openpty: No such file or directory Jan 1 00:26:27 smios-initramfs authpriv.warn dropbear[197]: No pty was allocated,couldn't execute Jan 1 00:26:27 smios-initramfs authpriv.info dropbear[197]:Exit(root)from<192.168.1.98:65234>: Exited normally Jan 1 00:26:27 smios-initramfs authpriv.info dropbear[198]:Exitbefore authfrom<192.168.1.98:65237>: Exited normally ^X^CJan 1 00:26:35 smios-initramfs authpriv.info dropbear[196]: Earlyexit: Terminated by signal报错显示我没有/dev/pts目录
执行临时命令测试：
mkdir/dev/ptsmount-t devpts devpts/dev/pts临时解决方案如下：
在/etc/init.d/rcS文件之后添加：
[-d/dev/pts]||mkdir-p/dev/ptsmount-t devpts devpts/dev/pts