yum groupinstall -y "Development Tools"
yum install -y imake rpm-build pam-devel krb5-devel zlib-devel libXt-devel libX11-devel gtk2-devel perl-IPC-Cmd

# For CentOS5:
yum install gcc44

Usage

Build RPMs

# 1. Install build requirements as listed above.
# 2. Edit version.env file if necessary.

# 3. Download source packages.
./pullsrc.sh
# if any error comes up, manally download the source files into the `downloads` dir.

# 4. Run the script to build RPMs. 
./compile.sh

# For CentOS 5 
./compile.sh el5
# CentOS5 didn't set the variable of `${dist}`, manually run the script with argument.

Install RPMs

# Backup current SSH config
if test -e /etc/ssh/sshd_config; then
  mv /etc/ssh/sshd_config /etc/ssh/sshd_config.$(date +%Y%m%d)
fi

# Force install compiled packages.
yum install -y coreutils
OS_DIST="$(rpm --eval '%{?dist}'|tr -d '.')"
[ -z "$OS_DIST" ] && OS_DIST="el5"
BASE_PATH="$PWD/$OS_DIST/RPMS/$(uname -m)"

yum --disablerepo=* localinstall $BASE_PATH/openssh-*.rpm

# in case host key files got permissions too open.
chmod -v 600 /etc/ssh/ssh_host_*_key

# For CentOS7:
# in some cases the previously installed systemd unit file is left on disk,
# which causes systemd mixing unit files and initscripts units provided by this package.
if [[ -d /run/systemd/system && -f /usr/lib/systemd/system/sshd.service ]]; then
    mv /usr/lib/systemd/system/sshd.service /usr/lib/systemd/system/sshd.service.$(date +%Y%m%d)
    systemctl daemon-reload
fi

# Restart service
service sshd restart

Use Docker

See file docker.README.md

Security Notes

This package provide following options in /etc/ssh/sshd_config to work like triditional sshd.

PubkeyAcceptedAlgorithms +ssh-rsa
PermitRootLogin yes
PasswordAuthentication yes
UseDNS no
UsePAM yes
KexAlgorithms -diffie-hellman-group1-sha1,diffie-hellman-group1-sha256,diffie-hellman-group14-sha1,diffie-hellman-group14-sha256,diffie-hellman-group15-sha256,diffie-hellman-group15-sha512,diffie-hellman-group16-sha256,diffie-hellman-group16-sha512,diffie-hellman-group17-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha512