Create combined PEM file from private key and certificate for Apple Push Notification.

create_apple_push_pem.sh

#!/bin/sh

if [ -z "$1" -o "$1" = "-h" -o "$1" = "--help" ]; then
  echo "Usage: $0 private_key.p12 certificate.{p12, der}"
  echo "You can export the private key (and certificate) in PKCS12 format from Keychain.app."
  exit 0
fi

# Create private key in PEM format from PKCS12 format without password.
openssl pkcs12 -in "$1" -nocerts -nodes -out _key.pem

# Create certificate in PEM format from PKCS12 format or DER format.
if [ "${2##*.}" = "p12" ]; then
  openssl pkcs12 -in "$2" -clcerts -nokeys -out _cert.pem
else
  openssl x509 -inform der -in "$2" -out _cert.pem
fi

# Concat them
cat _cert.pem _key.pem > apple_push.pem
# Remove remporary pem files.
rm _cert.pem _key.pem