Enable sshd on 2440

TurnToJPG -->

Package Preparation

For openssh requires the following packages, first we have to download them all from internet.
zlib, openssl, openssh.

$ wget http://zlib.net/zlib-1.2.8.tar.gz
$ wget https://www.openssl.org/source/openssl-0.9.8zc.tar.gz
$ wget http://mirror.internode.on.net/pub/OpenBSD/OpenSSH/portable/openssh-6.7p1.tar.gz


Cross-compile zlib

We have to manually change the following line in Makefile :

LDSHARED=gcc -shared -Wl,-soname,libz.so.1,--version-script,zlib.map
LDSHARED=arm-linux-gcc -shared -Wl,-soname,libz.so.1,--version-script,zlib.map


$ ./configure --prefix=/media/nfs/rootfs/usr/
$ make CC=arm-linux-gcc AR=arm-linux-ar LD=arm-linux-ld
$ make install

Cross-compile openssh

Get the openssl’s configure help menus:

# ./Configure --help
Usage: Configure [no-<cipher> ...] [enable-<cipher> ...] [experimental-<cipher> ...] [-Dxxx] [-lxxx] [-Lxxx] [-fxxx] [-Kxxx] [no-hw-xxx|no-hw] [[no-]threads] [[no-]shared] [[no-]zlib|zlib-dynamic] [enable-montasm] [no-asm] [no-dso] [no-krb5] [386] [--prefix=DIR] [--openssldir=OPENSSLDIR] [--with-xxx[=vvv]] [--test-sanity] os/compiler[:flags]

Then configure the building via:

$ ./Configure --prefix=/media/nfs/rootfs/usr os/compiler:/opt/cross/arm-linux-gcc_4.3.2/bin/arm-linux-gcc
$ make && make install

Cross-compile openssh

Configure the openssh via following command, the lib’s directory should be adjust to previous installed directory:

$ /configure --host=arm-linux --with-libs --with-zlib=/media/nfs/rootfs/usr/ --with-ssl-dir=/media/nfs/rootfs/usr/ --disable-etc-default-login CC=/opt/cross/arm-linux-gcc_4.3.2/bin/arm-linux-gcc

Make but don’t install.
Install steps:

$ cp sshd /media/nfs/rootfs/usr/local/sbin/
$ cp scp sftp ssh ssh-add ssh-agent ssh-keygen ssh-keyscan /media/nfs/rootfs/usr/local/bin/
$ cp sftp-server ssh-keysign /media/nfs/rootfs/usr/local/libexec/

In 2440 board, run:

[root@TrustyArch busybox-1.22.1]# mkdir -p /usr/local/etc/
[root@TrustyArch busybox-1.22.1]# mkdir -p /var/run/
[root@TrustyArch busybox-1.22.1]# mkdir -p /var/empty/sshd
[root@TrustyArch busybox-1.22.1]# chmod 755 /var/empty

Generate the key files:

$ ssh-keygen -t rsa -f ssh_host_rsa_key -N ""
$ ssh-keygen -t rsa1 -f ssh_host_key -N ""
$ ssh-keygen -t dsa -f ssh_host_dsa_key -N ""
$ cp ssh_host_dsa_key ssh_host_dsa_key.pub ssh_host_key ssh_host_key.pub ssh_host_rsa_key ssh_host_rsa_key.pub /media/nfs/rootfs/usr/local/etc/

Add lines into /etc/passwd and /etc/group in embedded system rootfs:

$ cat /etc/passwd
sshd:*:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
$ cat /etc/group

Change the sshd_config file:

$ cp sshd_config /media/nfs/rootfs/usr/local/etc/
$ vim /media/nfs/rootfs/usr/local/etc/sshd_config
HostKey /usr/local/etc/ssh_host_key
HostKey /usr/local/etc/ssh_host_rsa_key
HostKey /usr/local/etc/ssh_host_dsa_key
PermitRootLogin yes
PermitEmptyPasswords yes
UsePrivilegeSeparation no
Subsystem	sftp	/usr/local/libexec/sftp-server

Then start the sshd via:


Good, we get segment fault, later will investigate this issue.