#!/bin/sh
#
# Post-installation script
#
# Copyright 2013 Guilhem Moulin <guilhem@fripost.org>
#
# Licensed under the GNU GPL version 3 or higher.

set -ue

find /home/ -mindepth 1 -maxdepth 1 -type d -print0 | xargs -r0 chmod og-rwx

user="$(sed -rn '0,/^([^:]*):[^:]*:1000:.*/s//\1/p' /etc/passwd)"
home="$(sed -rn '0,/^[^:]*:[^:]*:1000:[^:]*:[^:]*:([^:]*):.*/s//\1/p' /etc/passwd)"

test -d "$home/.ssh" || mkdir -m 0700 "$home/.ssh"
# TODO: make something more generic
cat > "$home/.ssh/authorized_keys" << EOF
ssh-rsa ...
EOF
chown -R "$user:$user" "$home/.ssh"
chmod -R og-rwx "$home/.ssh"

# Delete the automatically generated keys, and replace by our own
rm /etc/ssh/ssh_host_*_key /etc/ssh/ssh_host_*_key.pub
ssh-keygen -b 4096 -t rsa -N '' -C /etc/ssh/ssh_host_rsa_key -f /etc/ssh/ssh_host_rsa_key

cat > /etc/ssh/sshd_config << EOF
# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes

# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768

# Logging
SyslogFacility AUTH
LogLevel INFO

# Authentication:
LoginGraceTime 120
PermitRootLogin no
DenyUsers *
StrictModes yes

RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile     %h/.ssh/authorized_keys

# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
#IgnoreUserKnownHosts yes

# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no

# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no

# Change to no to disable tunnelled clear text passwords
PasswordAuthentication no

# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

X11Forwarding no
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no

#MaxStartups 10:30:60
#Banner /etc/issue.net

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

Subsystem sftp /usr/lib/openssh/sftp-server

# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication.  Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM no
EOF

# TODO: the full list hangs
#apt-get autoremove --purge \
#    dictionaries-common \
#    eject \
#    ispell \
#    laptop-detect \
#    nano \
#    tasksel \
#    wamerican \
#    wbritish \
#|| true

sudo update-alternatives --set editor /usr/bin/vim.nox

# TODO: initramfs