Roughenough

Roughenough is a Roughtime secure time synchronization server implemented in Rust.

The server is bare-bones, but functionally complete: it parses client requests and generates valid Roughtime responses. Rough edges and unimplemented features remain, see limitations below. Contributions are welcome.

Building and Running

Starting the Server

bash $ cargo run --release --bin server /path/to/config.file ... 2017-07-03T19:39:45-05:00 [INFO] Roughenough server v0.1 starting 2017-07-03T19:39:45-05:00 [INFO] Long-term public key: d0756ee69ff5fe96cbcf9273208fec53124b1dd3a24d3910e07c7c54e2473012 2017-07-03T19:39:45-05:00 [INFO] Ephemeral public key: 575d5ed128143c0f7a5cdaf476601dd1b8a192a7199e62c0d2c039b53234d062 2017-07-03T19:39:45-05:00 [INFO] Server listening on 127.0.0.1:8686

The resulting binary is target/release/server. After building you can copy the binary and run on its own (no cargo needed):

bash $ cp target/release/server /usr/local/bin $ /usr/local/bin/server /path/to/config.file

Configuration File

The server is configured via a YAML file:

yaml interface: 127.0.0.1 port: 8686 seed: f61075c988feb9cb700a4a6a3291bfbc9cab11b9c9eca8c802468eb38a43d7d3

Where:

interface - IP address or interface name for listening to client requests
port - UDP port to listen for requests
seed - A 32-byte hexadecimal value used to generate the server's long-term key pair. This is a secret value, treat it with care.

Stopping the Server

Use Ctrl-C or kill the process.

Limitations

Roughtime features not implemented:

Leap-second smearing.
Ecosystem-style response fault injection.
On-line key rotation. The server must be restarted to generate a new delegated key.
Multi-request Merkle Tree batching. For now each request gets its own response with PATH empty and INDX zero.

Other notes:

Error-handling is not robust. There are unwrap()'s and expect()'s in the request handling path.
The server is a simple single-threaded recv_from loop. mio and tokio are intentionally avoided to keep the implementation straightforward and maximize comprehensibility by newbie Rustaceans. Blazing async ninja speed is not a goal.
Per-request heap allocations could be reduced: a few Vec's could be replaced by lifetime scoped slices.
Constants aren't consistently used. A few hard-coded magic numbers remain.
Goal of using self-contained dependencies did not bear fruit. Many transitive dependencies lengthen the build-time. Build is (to me) too long for such a simple project.

About the Roughtime Protocol

Roughtime is a protocol that aims to achieve rough time synchronisation in a secure way that doesn't depend on any particular time server, and in such a way that, if a time server does misbehave, clients end up with cryptographic proof of it. It was created by Adam Langley and Robert Obryk.

Contributors

Stuart Stock, original author and current maintainer (stuart {at} int08h.com)

Copyright and License

int08h LLC licenses Roughenough (the "Software") to you under the Apache License, version 2.0 (the "License"); you may not use this Software except in compliance with the License. You may obtain a copy of the License from the LICENSE file included with the Software or at:

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.