source: npl/sshkeyfix @ 105afb5

#!/bin/bash
# Ssh keyfix version 2.0

if [ -z $1 ]; then
 echo "Usage: $0 user@host"
 echo "Installs your public ssh key to host, if neccesary"
 exit 1
fi

if [ ! -f ~/.ssh/id_rsa ]; then
 ssh-keygen -N "" -b 2048 -t rsa -f ~/.ssh/id_rsa || exit 1
fi

PUB="`cat ~/.ssh/id_rsa.pub`" || exit 1

echo -n "Checking ssh key on $1..."


checkkey()
{
    ssh $OPTS $1 "
        mkdir ~/.ssh &>/dev/null
        if ! grep '$PUB' ~/.ssh/authorized_keys &>/dev/null; then
                echo -n 'Installing public key...'
                echo '$PUB' >> ~/.ssh/authorized_keys
        fi"
}

checkkey $1
EXIT=$?

#remove hostkey and retry
if [ $EXIT == 255 ]; then
    TARGETHOST=`echo $1 | sed s/.*@//`
    echo -n "SSHKEYFIX: Removing hostkey of $TARGETHOST..."
    cat ~/.ssh/known_hosts | grep -v "^$TARGETHOST " > ~/.ssh/known_hosts.$$ || exit 1
    mv ~/.ssh/known_hosts.$$ ~/.ssh/known_hosts || exit 1
    echo "OK"
    checkkey $1
    EXIT=$?
fi

if [ $EXIT == 0 ]; then
    echo "OK"
    exit 0
else
    echo "ERROR!"
    exit 1
fi