Create self-signed certificate with root and ca for development

generate-certificate-chain.sh

#!/bin/bash

rm *.jks 2> /dev/null
rm *.pem 2> /dev/null

echo "===================================================="
echo "Creating fake third-party chain root -> ca"
echo "===================================================="

# generate private keys (for root and ca)

keytool -genkeypair -alias root -dname "cn=Local Network - Development" -validity 10000 -keyalg RSA -keysize 2048 -ext bc:c -keystore root.jks -keypass password -storepass password
keytool -genkeypair -alias ca -dname "cn=Local Network - Development" -validity 10000 -keyalg RSA -keysize 2048 -ext bc:c -keystore ca.jks -keypass password -storepass password

# generate root certificate

keytool -exportcert -rfc -keystore root.jks -alias root -storepass password > root.pem

# generate a certificate for ca signed by root (root -> ca)

keytool -keystore ca.jks -storepass password -certreq -alias ca \
| keytool -keystore root.jks -storepass password -gencert -alias root -ext bc=0 -ext san=dns:ca -rfc > ca.pem

# import ca cert chain into ca.jks

keytool -keystore ca.jks -storepass password -importcert -trustcacerts -noprompt -alias root -file root.pem
keytool -keystore ca.jks -storepass password -importcert -alias ca -file ca.pem

echo  "===================================================================="
echo  "Fake third-party chain generated. Now generating my-keystore.jks ..."
echo  "===================================================================="

# generate private keys (for server)

keytool -genkeypair -alias server -dname cn=server -validity 10000 -keyalg RSA -keysize 2048 -keystore my-keystore.jks -keypass password -storepass password

# generate a certificate for server signed by ca (root -> ca -> server)

keytool -keystore my-keystore.jks -storepass password -certreq -alias server \
| keytool -keystore ca.jks -storepass password -gencert -alias ca -ext ku:c=dig,keyEnc -ext "san=dns:localhost,ip:192.1.1.18" -ext eku=sa,ca -rfc > server.pem

# import server cert chain into my-keystore.jks

keytool -keystore my-keystore.jks -storepass password -importcert -trustcacerts -noprompt -alias root -file root.pem
keytool -keystore my-keystore.jks -storepass password -importcert -alias ca -file ca.pem
keytool -keystore my-keystore.jks -storepass password -importcert -alias server -file server.pem

echo "================================================="
echo "Keystore generated. Now generating truststore ..."
echo "================================================="

# import server cert chain into my-truststore.jks

keytool -keystore my-truststore.jks -storepass password -importcert -trustcacerts -noprompt -alias root -file root.pem
keytool -keystore my-truststore.jks -storepass password -importcert -alias ca -file ca.pem
keytool -keystore my-truststore.jks -storepass password -importcert -alias server -file server.pem

Update: when I look at root.pem with a hex editor, I see that it's UTF-16 (what Windows calls UNICODE). If I copy and paste it as UTF-8, then it imports it fine. That means something about how keytool pipes this out is causing it.

By the way, I'm using Powershell on Windows. That's probably the problem, somehow.

Yes, the problem was Powershell. When you use the '>' operator to send output to a file, it's an alias for Out-File. Out-File writes as UTF-16 by default.

The answer is to replace "> root.pem" with "| Out-File root.pem -encoding ASCII".

Hopefully, this will help a weary traveller.

Thank you , this is amazing

Thank you!

It seems promising since it uses keytool for the entire procedure. Unfortunately it does not create the client side *.crt file that I need. This way the clients browsers will always show the security warning since I cannot import the certificate to windows trusted certificate authorities.

Perfect ! Thank you!

Thanks but why do you use "-ext eku=sa,ca"?

Thanks but why do you use "-ext eku=sa,ca"?

it's is an Extended Key Usage for TLS server authentication

https://tools.ietf.org/html/rfc5280#section-4.2.1.12