Tester le bon fonctionnement du cryptage SSL/TLS d’un serveur mail
Ce site très utile pour les administrateurs système permet de tester depuis l’extérieur le support TLS d’un serveur mail SMTP, que ce soit en connexion cryptée implicite ou explicite (STARTTLS).
Il donne le détail du certificat utilisé, le protocole exact (version de TLS en cipher), bref un diagnostic en profondeur et exhaustif.
Il est gratuit et très simple d’utilisation.
https://www.checktls.com/TestReceiver
La description du site en anglais :
When you click Run Test, //email/testTo: (« TestReceiver ») performs all the steps that Internet email systems go through to send email. It records every command and byte of data it sends and every answer and byte of data that the other email system sends. TestReceiver never actually sends an email, it just gets as close as possible, learning as much about the remote system as it can.
Because CheckTLS focuses on security, TestReceiver tries to establish a secure (TLS) connection with the recipient’s system. Along with recording everything, it looks at the security of the recipient’s system for things like: certificate contents and signers, encryption algorithms, key lengths, hostname mis-matches, incorrect wild-card usage, weak cyphers, etc.