Privacy policy: easysync for desktop

1. Who is responsible

2. In short

easysync sends clipboard text and files between your own devices. The app has no account, no advertising, no analytics and no tracking service. Everything you send is encrypted on your computer and can be read only by the device you send it to.

The app contacts our servers in two cases only, and only if you choose them:

• The official relay (section 3), if you add it, or if you press Connect on a pairing link that names it. The app then asks it for an access key, and the relay sees technical connection data of your computer.
• The update check (section 4), if you switch it on or click “Check now”. The app then fetches one small file from our website.

If you use neither, the app connects only to your own devices and to the relays you added yourself.

3. Relays, and the official relay

A relay is a server that passes encrypted data between your devices when they cannot reach each other directly. A relay cannot read your clipboard text or files. It can see technical data: the IP addresses of your devices, when and for how long they connect, how much data they send, and that these devices talk to each other.

The official relay at relay.easysync.me is run by us, the company named in section 1. In the form for adding a relay the app preselects it for convenience. The app has no built-in connection to it: it connects only after you have added the relay. The same request is made when you join with a pairing link that names the official relay and press Connect. If you choose “Another relay”, whoever runs that relay is responsible for the data it sees, not we.

How the app gets its access key. When you add the official relay, the app sends one request over HTTPS to relay.easysync.me. The request has no content: no name, no device name, no app version, no identifier and no cookie. The relay answers with a random access key. The app stores the key on your computer, encrypted together with the other data of the app, and never shows it on screen. The app presents the key each time it connects to the relay.

What the official relay learns and stores because of the key:

• Your IP address and the time of the request. The relay keeps the address in memory for 24 hours, to limit how many keys one network address can request (for IPv6 addresses it keeps the first 64 bits). It does not write the address to disk, and the relay program does not log it.
• A hash of the key. The relay does not store the key itself. It stores a SHA-256 hash of it, the day the key was created and the day it expires. It stores no IP address and no device data with them.
• The key at every connection. The key belongs to your computer only. While it is valid, the relay can therefore see that connections come from the same computer, also when it changes its network or address. The relay keeps no list of connections.
• The last day of use. A key that is not used expires, currently after 30 days without use (we can change this setting). Every use moves the expiry day forward, so the stored expiry day shows, to the day, when a key was last used. The relay cannot tell whose key it is.

The key is not proof that a request comes from the easysync app: anyone can send the same request. We use it to limit abuse, not to identify you. “Remove” in the relay list deletes the key from your computer. The relay then cannot match the stored hash to you and forgets it when it expires.

4. The optional update check

The app can check whether a newer version exists. This check is off by default.

What the app asks for. When the check is on, the app fetches one small file from our website: https://easysync.me/updates/desktop/notice.json. The address is fixed in the app. The file contains only a version number, for example {"schema":1,"version":"0.4.1"}. The app compares that number with its own version. If the number is higher, the app shows a short notice with a button that opens the page easysync.me/download/ in your browser. The check itself requests nothing else.

When. About once a day, and once a few minutes after the app starts or after you switch the check on. That check at the start is skipped if the last attempt was less than an hour ago. The button “Check now” sends one request when you click it. It works even when the check is off, and it does not switch the check on.

What the request contains. No version number, no operating system, no device name, no identifier, no cookie, no data from your devices and no relay key. It is the same for every user. It names the program as “easysync-desktop”.

What our server can see. Like every request on the internet, the request shows our server:

• the IP address it comes from (your computer’s address, or the address of your network or of a service you route your traffic through),
• the date and time,
• the file that was requested,
• that an easysync desktop app is asking.

We do not store the IP address of these requests: our web server writes no access log (section 5).

What others on the network can see. Your DNS resolver learns that your computer looks up easysync.me. Your network provider can see that your computer connects to easysync.me. The connection is encrypted (HTTPS), so they do not see which file is requested. The check does not hide your IP address.

What the app does with the answer. It reads one version number and nothing else. It does not follow a link from the file, does not follow a redirect, and reads at most 4 KiB. It keeps a small settings file on your computer and sends it nowhere. The file holds: the switch itself; the time of its last attempt, which it also stores when you click “Check now” while the check is switched off (that stores no number); the newest version number it saw; the number you dismissed with “Not now” on a notice; the version of the app that ran last; whether you have answered the one-time offer; and, only until a version is recorded, a note that the offer is still owed.

What the check does not do. It never downloads or installs anything. To update, you open the download page, download the new version yourself and install it, as for the first install. The notice file is not signed. A notice therefore means only “a newer version may be available”. Check every download against its .sha256 file, as the download page describes.

Why it is off by default. The request shows our server your IP address and that you use easysync. You should decide that. After an update the app asks you once, in a line on the main screen, whether you want to switch the check on. It sends nothing before you answer, and nothing if you choose “Not now”.

How to switch it off. In the app: Settings, card “Updates”, switch “Check for new versions”. When you switch it off, the app stops checking and forgets the newest number it saw. The other items of the settings file stay.

5. Our servers and their logs

Our website, the update file and the official relay run on one server in Switzerland.

• Web server. The web server keeps no access log. Its operational log records start-up, certificate and error events, not individual requests; it contains neither a visitor’s IP address nor the requested address or headers. Only if debug logging were switched on, which it is not, would requests with IP addresses appear.
• Relay. The relay program logs its start and, once a minute, numbers such as how many connections are open. It logs no IP addresses and no access keys.
• The server itself. We have set up no other logging of visitors: no firewall log and no log of network traffic.

We keep these logs only for a short time.

The server is run by a hosting provider in Switzerland. The provider runs the network and the hardware. We have not switched on any logging of network traffic that the provider offers. What the provider records in its own systems to run its network is outside our control, and we cannot see it.

6. What we do not do

No account. No advertising. No analytics, crash-report or tracking library. We do not sell data. The app does not send the content of your clipboard or your files to us.

7. Applicable law and your rights

The controller is the company named in section 1, in Switzerland. This policy follows the Swiss Federal Act on Data Protection (FADP). The data is processed in Switzerland.

Legal basis. We process the IP address and the key hash on the official relay because we have an overriding private interest in operating the relay and protecting it against abuse. The update check runs only if you switch it on or click “Check now”, and this page tells you beforehand what it sends and what our server sees. We process the IP address of an update check only to answer that request.

Your rights. Under the FADP you can ask us whether we process personal data about you and receive the information you need to assert your rights (Article 25), ask us to correct or delete it or to stop processing it (Article 32), and, where the law provides for it, receive the data you gave us in a common electronic format (Article 28). You can report a violation to the Federal Data Protection and Information Commissioner (FDPIC), Feldeggweg 1, 3003 Bern, edoeb.admin.ch.

If you live in the European Union, the data protection law of your country may give you further rights; write to us and we will answer under the law that applies.

What we cannot look up. The relay does not know which computer or person a key hash belongs to, and we do not store the IP address of an update check. Requests about this data can therefore be answered only in general terms. We treat the key hash and the IP address as personal data.

To use a right, write to support@easysync.me. We may ask you to prove who you are before we give out information.

8. Changes

If the app changes in a way that touches this text, for example when the update check starts to download updates, we update this policy before that version is released. The date at the top is the date of the latest change of this policy.

9. Contact

support@easysync.me. Security problems: security@easysync.me.