Hello,
I have to implement encryption password between my clients and our open server.
Is there an easy way to do this with callback method ?

I saw in documentation that I have to write an encrypt function that will be
called when a callback event occur.

I don't really know what to put in this function ...
May someone help me ?

Hello,

Take a look at the Open Server sample program "ctos". In particular
take a look at the file "connect.c":
/*
** CTOS_ENCRYPTCB
**
** Callback for negotiated logins (password-encryption type).
** Relay encryption keys from remote server
** to remote client, and encrypted passwords from
** remote client to remote server.
**
** Parameters:
** conn Remote server connection.
** pwd Password to be encrypted (set by CT-Libary).
** pwdlen Original length of password.
** key Encryption key from remote server.
** keylen Length of key.
** buf Space for encrypted password from remote client.
** buflen Length of space.
** outlen Length of encrypted password.
**
** Returns:
** CS_FAIL or CS_SUCCEED.
*/