Ssh-keypair

From dghartung.com/docs

Below is the ssh-keypair script for allow two machines to talk to each automatically over ssh....use with caution!

#!/bin/bash
# 
# ssh-keyput -- set up passwordless openssh login.
#
# Copyright (C) 2001, 2002, 2006 by SWsoft.
# Author: Kir Kolyshkin
#
# This script is used to put your public ssh keys to another host's
# authorized_keys[2], so you will be able to ssh login without entering
# a password. Key pairs are generated if needed, and connectivity
# is checked after putting the keys.

PROGNAME=`basename $0`

function usage()
{
	echo "Usage: $PROGNAME [user@]IP [[user@]IP ...]" 1>&2
	exit 0
}

# Check for correct number of parameters
test $# -gt 0 || usage;

SSH_KEYGEN=`which ssh-keygen`
if test $? -ne 0; then
	# Error message is printed by 'which'
	exit 1
fi 

SSH_DIR=~/.ssh
if ! test -d $SSH_DIR; then
	mkdir $SSH_DIR
fi
chmod 700 $SSH_DIR


if [ ! -f $SSH_DIR/identity ] || [ ! -f $SSH_DIR/identity.pub ]; then
	echo "Generating ssh1 RSA keys - please wait..."
	rm -f $SSH_DIR/identity $SSH_DIR/identity.pub
	$SSH_KEYGEN -t rsa1 -f $SSH_DIR/identity -P 
	if [ $? -ne 0 ]; then
		echo "Command \"$SSH_KEYGEN -t rsa1 -f $SSH_DIR/identity" \
			 "-P \" failed" 1>&2
		exit 1
	fi
else
	echo "ssh1 RSA key is present"
fi

if [ ! -f $SSH_DIR/id_dsa ] || [ ! -f $SSH_DIR/id_dsa.pub ]; then
	echo "Generating ssh2 DSA keys - please wait..."
	rm -f $SSH_DIR/id_dsa $SSH_DIR/id_dsa.pub
	$SSH_KEYGEN -t dsa -f $SSH_DIR/id_dsa -P 
	if test $? -ne 0; then
		echo "Command \"$SSH_KEYGEN -t dsa -f $SSH_DIR/id_dsa" \
			 "-P \" failed" 1>&2
		exit 1
	fi
else
	echo "ssh2 DSA key is present"
fi

SSH1_RSA_KEY=`cat $SSH_DIR/identity.pub`
SSH2_DSA_KEY=`cat $SSH_DIR/id_dsa.pub`

for IP in $*; do
	echo "You will now be asked for password for $IP"
#	set -x
	ssh -oStrictHostKeyChecking=no $IP "mkdir -p ~/.ssh; chmod 700 ~/.ssh; \
		echo \"$SSH1_RSA_KEY\" >> ~/.ssh/authorized_keys; \
		echo \"$SSH2_DSA_KEY\" >> ~/.ssh/authorized_keys2; \
		chmod 600 ~/.ssh/authorized_keys ~/.ssh/authorized_keys2"
#	set +x
	if test $? -eq 0; then
		echo "Keys were put successfully"
	else
		echo "Error putting keys to $IP" 1>&2
	fi
done

for IP in $*; do
	for ver in 1 2; do
		echo -n "Checking $IP connectivity by ssh$ver... "
		ssh -q -oProtocol=${ver} -oBatchMode=yes \
		  -oStrictHostKeyChecking=no $IP /bin/true
		if [ $? -eq 0 ]; then
			echo "OK"
		else
			echo "failed" 1>&2
		fi
	done
done