#!/bin/sh
# csr.sh: Certificate Signing Request Generator
# Copyright(c) 2005 Evaldo Gardenali <evaldo@gardenali.biz>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. Neither the name of the author nor the names of its contributors may
#    be used to endorse or promote products derived from this software
#    without specific prior written permission.
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
# POSSIBILITY OF SUCH DAMAGE.
#
# ChangeLog:
# Mon May 23 00:14:37 BRT 2005 - evaldo - Initial Release

# be safe about permissions
LASTUMASK=`umask`
umask 077

# OpenSSL for HPUX needs a random file
RANDOMFILE=$HOME/.rnd

# create a config file for openssl
CONFIG=`mktemp -q /tmp/openssl-conf.XXXXXXXX`
if [ ! $? -eq 0 ]; then
    echo "Could not create temporary config file. exiting"
    exit 1
fi

echo "Private Key and Certificate Signing Request Generator"
echo "This script was designed to suit the request format needed by"
echo "the CAcert Certificate Authority. www.CAcert.org"
echo

printf "Short Hostname (ie. imap big_srv www2): "
read HOST
printf "FQDN/CommonName (ie. www.example.com) : "
read COMMONNAME

echo "Type SubjectAltNames for the certificate, one per line. Enter a blank line to finish"
SAN=1        # bogus value to begin the loop
SANAMES=""   # sanitize
while [ ! "$SAN" = "" ]; do
    printf "SubjectAltName: DNS:"
    read SAN
    if [ "$SAN" = "" ]; then break; fi # end of input
    if [ "$SANAMES" = "" ]; then
        SANAMES="DNS:$SAN"
    else
        SANAMES="$SANAMES,DNS:$SAN"
    fi
done

# Config File Generation

cat <<EOF > $CONFIG
# -------------- BEGIN custom openssl.cnf -----
 HOME                    = $HOME
EOF

if [ "`uname -s`" = "HP-UX" ]; then
    echo " RANDFILE                = $RANDOMFILE" >> $CONFIG
fi

cat <<EOF >> $CONFIG
 oid_section             = new_oids
 [ new_oids ]
 [ req ]
 default_days            = 730            # how long to certify for
 default_keyfile         = $HOME/${HOST}_privatekey.pem
 distinguished_name      = req_distinguished_name
 encrypt_key             = no
 string_mask = nombstr
EOF

if [ ! "$SANAMES" = "" ]; then
    echo "req_extensions = v3_req # Extensions to add to certificate request" >> $CONFIG
fi

cat <<EOF >> $CONFIG
 [ req_distinguished_name ]
 commonName              = Common Name (eg, YOUR name)
 commonName_default      = $COMMONNAME
 commonName_max          = 64
 [ v3_req ]
EOF

if [ ! "$SANAMES" = "" ]; then
    echo "subjectAltName=$SANAMES" >> $CONFIG
fi

echo "# -------------- END custom openssl.cnf -----" >> $CONFIG

echo "Running OpenSSL..."
openssl req -batch -config $CONFIG -newkey rsa:2048 -out $HOME/${HOST}_csr.pem
echo "Copy the following Certificate Request and paste into CAcert website to obtain a Certificate."
echo "When you receive your certificate, you 'should' name it something like ${HOST}_server.pem"
echo
cat $HOME/${HOST}_csr.pem
echo
echo The Certificate request is also available in $HOME/${HOST}_csr.pem
echo The Private Key is stored in $HOME/${HOST}_privatekey.pem
echo

rm $CONFIG

#restore umask
umask $LASTUMASK