gistfile1.txt

Integration/Signing_Site_Association_File.txt

1. Convert all Certificates (*.crt) to PEM files:
openssl x509 -in EssentialSSLCA_2.crt -out EssentialSSLCA_2.der -outform DER
openssl x509 -in EssentialSSLCA_2.der -inform DER -out EssentialSSLCA_2.pem -outform PEM

2. Sign apple-app-site-association.json file with proper keychain:
-inkey: Private Key
-signer: Signed Certificate from Signing agency
-certfile: Certificate used to sign "signer" key
 

cat apple-app-site-association.json | openssl smime -sign 
	-inkey my-key-file.key 
	-signer my-signing-certificate.pem 
	-certfile EssentialSSLCA_2.pem -noattr -nodetach -outform DER > apple-app-site-association

3. Place apple-app-site-association file at root of server