FTP, SFTP or other? Secure transmission protocol usable through browser

Question

I'm looking for a secure transmission protocol that can be accessed through the web browser. The user should be able only to access/modify only some folder, not the whole filesystem.

For example I'd like to access to my server visiting a link of this kind:

ftp://mysite.com

Unfortunately ftp is not secure at all and sounds a bit anachronistic in 2017.

SFTP has three problem:

1. I cannot access through browser from a Mac PC (I need a software like filezilla).
2. With the same credential I can access through SSH to the terminal.
3. I cannot restrict the accessible directory.

Do you have any suggestion to achieve what I want? I've raspbian on a raspberry pi 3 and the service that I want to create for the moment is restricted to a limited number of people, so I cannot effort to purchase certificates, external server or proprietary solution.

I know that exist also FTPS and FTP over SSH but I really don't know if these are the best and easiest solution

Answer 1

You can configure Apache or NGINX for WebDAV, which allows files uploads as well. I recommend you use TLS with authentication (digest or plain) for uploading.

You can also set up web server for file download and do uploading using SFTP. You can restrict specific user/group to sftp (no shell) and chroot (limited filesystem tree) by customizing your sshd_config. Wikibooks has some example configurations.

Answer 2

Another solution would be to use a cloud-based SFTP SaaS solution. While using a SaaS (software as a service) solution will cost money, it could save time and money over a self-hosting solution -- pending your growth and future requirements.

I work with a cloud-based SFTP SaaS solution, ExaVault. With our service (and many other SaaS solutions) you have access to the following features as soon as you finish your account creation (with links to show examples):

• A URL for your server (for example, mycompany.exvault.com)
• Ability to add users, set individual permissions, and assign their home directory to keep data separate
• Ability to set security options such as SFTP/HTTPS only connections and generate SSH Keys for users.
• Options for connecting through web browsers or using integrations such as FTP Clients, custom scripts from the command line, and API integrations.

In addition to costs, moving to a SaaS means you will not have the physical access to your servers. For smaller projects or specific workflows, that may be a requirement.

But, if you anticipate your FTP needs to grow to a large size, cloud-based SFTP SaaS will help decrease the the time, effort, and costs of a in-house solution (such as: coordinating with server hosts, implementing security protocols, creating a process/user interface for interacting with your data, ongoing maintenance, software updates, etc).