SMTP Nostr Gateway

Dependencies

• Node v18
• iptables or ufw (not explained here)

Getting Started

1. Add firewall rules to allow SMTP traffic (see this guide to make this change permanent)

   sudo iptables -A INPUT -p tcp --dport 25 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
   sudo iptables -A OUTPUT -p tcp --sport 25 -m conntrack --ctstate ESTABLISHED -j ACCEPT

2. Create key & certificate for TLS

   # Warning: Follow the steps below at your own risk
   
   export DOMAIN=your.domain # e.g. wlvs.space
   
   cd certs/
   
   # Generate private key
   openssl genrsa -des3 $DOMAIN.key 1024
   
   # Generate certificate sign request
   openssl req -new -key $DOMAIN.key -out $DOMAIN.csr
   
   # Remove passphrase from key
   openssl rsa -in $DOMAIN.original -out $DOMAIN.key
   
   # Generate certificate from request & private key
   openssl x509 -req -days 365 -in $DOMAIN.csr -signkey $DOMAIN.key -out $DOMAIN.crt
   
   # Update the cert and key file on index.js 

3. Create file with secret (once)

   mkdir -p /etc/smtp-nostr-gateway
   echo -n "definitely-do-not-use-this-secret" | sudo tee /etc/smtp-nostr-gateway/secret

4. Install packages

   npm install

5. Run

   sudo SECRET=$(cat /etc/smtp-nostr-gateway/secret) node index.js