Convert PFX certificates to PEM format

pfx2pem.sh

#!/usr/bin/env bash
# 
# Convert PFX certficates to PEM format
# Jonas Björk, jonas.bjork@gmail.com
# Helsingborg, Sweden, 2019-02-13 
#
echo "> PFX to PEM certificate converter"

# If no certificate file is stated, bail out with syntax help
if [ $# -eq 0 ] ; then
    echo "Syntax: ${0} pfx_file"
    exit 1
fi

# If input certificate does not exist, there is no use of continue this
ORIG_CERT=${1}
echo "| Original certificate (PFX): ${ORIG_CERT}"
if [ ! -f ${ORIG_CERT} ] ; then
    echo "! Error: ${ORIG_CERT} not found!"
    exit 1
fi

# Make sure we have an output directory
if [ ! -d "out/" ] ; then
    echo "| Creating out/ directory"
    mkdir out
fi

# Get the certificate name without extension (.pfx)
CERT_NAME=${ORIG_CERT%.*}

# Make some sanity checks, DO NOT OVERWRITE existing certs
if [ -f out/${CERT_NAME}.pem ] ; then
    echo "! File: out/${CERT_NAME}.pem already exists! I do not touch it!"
    exit 1
fi
if [ -f out/${CERT_NAME}.key ] ; then
    echo "! File: out/${CERT_NAME}.key already exists! I do not touch it!"
    exit 1
fi

echo "| #1 : You must specify the password for the certificate you are importing!"
openssl pkcs12 -in ${ORIG_CERT} -clcerts -nokeys -out out/${CERT_NAME}.pem
echo "| #2 : ...and import password again, this time we are creating the key"
echo "> PEM pass phrase is the pass phrase you want for the new certficate"
openssl pkcs12 -in ${ORIG_CERT} -nocerts -out out/${CERT_NAME}.tmpkey
echo "| #3 : .. finally we are making the new key pass phrase less"
echo "> Use the pass phrase you just set up in the second step."
openssl rsa -in out/${CERT_NAME}.tmpkey -out out/${CERT_NAME}.key
rm out/${CERT_NAME}.tmpkey

exit 0