I have the same objective for giving the opportunity to our suppliers/clients to fill/update all the data that are needed to trade with them in a safe and productive way.

The idea could be to create a template form available on the website; the fields of the form should be automatically updated into the database. 

The Oauth protocol must be used to secure the process; I have no idea how to implement it on a Odoo database (although Odoo has a Oauth setting to access the Google/Facebook user accounts

 May be someone from this community will be able to provide useful information!