Output the certificate chain of a given certificate, optionally including the private key

output-cert-chain.sh

#!/bin/bash

cert="$1"
key="$2"


if [ -z "$cert" -o ! -e "$cert" ]; then
        echo "Usage: $0 <cert.pem> [cert.key]"
        exit 1
fi

# Temporary file.
tmpfile="/tmp/`date +%s`.$$"
cleanup()
{
        rm -f "$tmpfile"
}
trap cleanup EXIT
touch $tmpfile

# Do the magic
dump_issuer_cert()
{
        in="$1"

        issuer_hash=`openssl x509 -noout -text -in "$in" -issuer_hash | tail -1`
        if grep -q $issuer_hash "$tmpfile"; then
                echo "Certificate $in with issuer hash $issuer_hash already seen" > /dev/stderr
                return 1
        fi
        base_path="/etc/ssl/certs/${issuer_hash}"
        if [ -e "${base_path}.0" ]; then
                fn="${base_path}.0"
        elif [ -e "${base_path}.1" ]; then
                fn="${base_path}.1"
        else
                echo "No certificates found with path ${base_path}*"
                return 1
        fi

        cat "$fn"
        echo $issuer_hash >> $tmpfile
        dump_issuer_cert "$fn"
        return 0
}

cat "$cert"
dump_issuer_cert "$cert"
if [ ! -z "$key" ]; then
        cat "$key"
fi