macaddcert.sh -- pull TLS cert from a URL and add it to trusted keystore

macaddcert.sh

#!/bin/bash

# add the security certificate of a host to macos keychain

if [[ -z $1 ]]; then
    echo USAGE: $0 hostname
    exit
fi
host=$1
tmpfile=/tmp/${host}.pem

openssl x509 -in <(openssl s_client -connect ${host}:443 -prexit 2>/dev/null) > $tmpfile
if ! grep -q "END CERTIFICATE" $tmpfile; then
    echo issue with openssl
    exit
fi
sudo security add-trusted-cert -d -r trustRoot -k /Library/Keychains/System.keychain $tmpfile