There may be some situations where you want to encrypt FTP traffic with SSL certificates rather than using SFTP with SSH. Using vsftpd with SSL encryption is quite easy, and here’s how it’s done:
First, you’ll need to make a new self-signed SSL certificate (if you don’t have a key and certificate available already):
openssl req [...]
Create a strong CSR and private key
openssl req -new -nodes -newkey rsa:2048 -out server.crt -keyout server.key
Parsing out the data within a certificate
openssl asn1parse -in server.crt
Checking a certificate/key modulus to see if they correspond
openssl rsa -in server.key -modulus -noout | openssl md5
openssl x509 -in server.crt -modulus -noout | openssl md5
Convert a key from PEM -> DER
openssl [...]