Roughenough is an RFC-draft compliant Roughtime secure time synchronization client and server implementation in Rust.
Roughenough's server and client are functionally complete and at feature parity with the reference C++ and Golang implementations.
Requires latest stable Rust to compile. Contributions welcome, see CONTRIBUTING for instructions and limitations for areas that could use attention.
Roughenough implements the Roughtime protocol as specified in the draft-5 RFC.
Important differences from the draft RFC
1. Roughenough uses SHA-512/256 to compute the Merkle tree. Draft-5 of the RFC uses a
bespoke 32-byte SHA-512 prefix without rationale or justification. Given that
standardized 32-byte SHA-512/256 exists and is already implemented widely, I'm
sticking with it while I advocate for the RFC to move away from the custom prefix
and adopt SHA-512/256.
2. The server and client send/expect RFC protocol version 1 (VER tag is 0x00000001)
instead of the draft's suggested 0x80000000 + version.
The Roughenough server operates both the "classic" protocol and the RFC compliant protocol at the same time on a single serving port (the 8-byte magic frame value added by the RFC is used to distinguish classic vs. rfc requests).
The new -p/--protocol flag of roughenough-client controls the protocol version to
use in requests (0 = classic protocol, 1 = RFC protocol). The default is 0 the
"classic" protocol, until the RFC is finalized:
```
$ roughenough-client -p 1 roughtime.int08h.com 2002 ```
Roughenough uses 2018 edition features and requires Rust 1.31 or newer to build.
```bash
$ cargo build --release ```
The client binary is target/release/roughenough-client. After building you can copy the
binary and run on its own (no cargo needed) if you wish.
bash
$ cp target/release/roughenough-client /usr/local/bin
bash
$ target/release/roughenough-client -v roughtime.int08h.com 2002
Requesting time from: "roughtime.int08h.com":2002
Received time from server: midpoint="Oct 26 2018 23:20:44", radius=1000000, verified=No (merkle_index=0)
Oct 26 2018 23:20:44
You can use the date utility on Linux machines to set the system time to the time determined by the Roughenough client:
bash
sudo date --utc --set "$(roughenough-client -z roughtime.int08h.com 2002)"
You can use the date utility on FreeBSD machines to set the system time to the time determined by the Roughenough client:
bash
sudo date -u "$(roughenough-client -z roughtime.int08h.com 2002 -f %Y%m%d%H%M.%S)"
Use the -p flag with the client to validate the server's response with its public key.
```bash
$ host -t TXT roughtime.int08h.com roughtime.int08h.com descriptive text "016e6e0284d24c37c6e4d7d8d5b4e1d3c1949ceaa545bf875616c9dce0c9bec1"
$ target/release/roughenough-client -v roughtime.int08h.com 2002 -p 016e6e0284d24c37c6e4d7d8d5b4e1d3c1949ceaa545bf875616c9dce0c9bec1 Requesting time from: "roughtime.int08h.com":2002 Received time from server: midpoint="Oct 26 2018 23:22:20", radius=1000000, verified=Yes (merkle_index=0) Oct 26 2018 23:22:20 ```
The verified=Yes in the output confirms that the server's response had a valid signature.
There are two (mutually exclusive) ways to configure the Roughenough server:
The server accepts the following configuration parameters:
YAML Key | Environment Variable | Necessity | Description
--- | --- | --- | ---
interface | ROUGHENOUGH_INTERFACE | Required | IP address or interface name for listening to client requests
port | ROUGHENOUGH_PORT | Required | UDP port to listen for requests
seed | ROUGHENOUGH_SEED | Required | A 32-byte hexadecimal value used to generate the server's long-term key pair. This is a secret value and must be un-guessable, treat it with care. (If compiled with KMS support, length will vary; see Optional Features)
batch_size | ROUGHENOUGH_BATCH_SIZE | Optional | The maximum number of requests to process in one batch. All nonces in a batch are used to build a Merkle tree, the root of which is signed. Default is 64 requests per batch.
status_interval | ROUGHENOUGH_STATUS_INTERVAL | Optional | Number of seconds between each logged status update. Default is 600 seconds (10 minutes).
health_check_port | ROUGHENOUGH_HEALTH_CHECK_PORT | Optional | If present, enable an HTTP health check responder on the provided port. Use with caution, see Optional Features.
kms_protection | ROUGHENOUGH_KMS_PROTECTION | Optional | If compiled with KMS support, the ID of the KMS key used to protect the long-term identity. See Optional Features.
fault_percentage | ROUGHENOUGH_FAULT_PERCENTAGE | Optional | Likelihood (as a percentage) that the server will intentionally return an invalid client response. An integer range from 0 (disabled, all responses valid) to 50 (50% of responses will be invalid). Default is 0 (disabled).
The table above lists the YAML keys available in the config file. An example:
yaml
interface: 127.0.0.1
port: 8686
seed: f61075c988feb9cb700a4a6a3291bfbc9cab11b9c9eca8c802468eb38a43d7d3
Provide the config file as the single command-line argument to the Roughenough server binary:
bash
$ /path/to/roughenough-server /path/to/config.yaml
Roughenough can be configured via the ROUGHENOUGH_* environment variables
listed in the table above. Start the server with a single ENV argument to have Roughenough configure itself
from the environment. Example:
bash
$ export ROUGHENOUGH_INTERFACE=127.0.0.1
$ export ROUGHENOUGH_PORT=8686
$ export ROUGHENOUGH_SEED=f61075c988feb9cb700a4a6a3291bfbc9cab11b9c9eca8c802468eb38a43d7d3
$ /path/to/roughenough-server ENV
```bash
$ cargo build --release
$ target/release/roughenough-server example.cfg 2018-07-25 00:05:09 INFO [server] Roughenough server v1.0.5 starting 2018-07-25 00:05:09 INFO [server] Long-term public key: d0756ee69ff5fe96cbcf9273208fec53124b1dd3a24d3910e07c7c54e2473012 2018-07-25 00:05:09 INFO [server] Ephemeral public key: 25fd5dc31ceee241aed3e643534e95ed0609e9a20982a45ac0312a5f55e2cc66 2018-07-25 00:05:09 INFO [server] Server listening on 127.0.0.1:8686
$ export ROUGHENOUGHINTERFACE=127.0.0.1 $ export ROUGHENOUGHPORT=8686 $ export ROUGHENOUGH_SEED=f61075c988feb9cb700a4a6a3291bfbc9cab11b9c9eca8c802468eb38a43d7d3 $ target/release/roughenough-server ENV 2018-07-25 00:05:09 INFO [server] Roughenough server v1.0.5 starting 2018-07-25 00:05:09 INFO [server] Long-term public key: d0756ee69ff5fe96cbcf9273208fec53124b1dd3a24d3910e07c7c54e2473012 2018-07-25 00:05:09 INFO [server] Ephemeral public key: 25fd5dc31ceee241aed3e643534e95ed0609e9a20982a45ac0312a5f55e2cc66 2018-07-25 00:05:09 INFO [server] Server listening on 127.0.0.1:8686 ```
The resulting binary is target/release/roughenough-server. After building you can copy the
binary and run on its own (no cargo needed):
bash
$ cp target/release/roughenough-server /usr/local/bin
Use Ctrl-C or kill the process.
Roughenough has two opt-in (disabled by default) features that are enabled either A) via a config setting, or B) at compile-time.
See OPTIONAL-FEATURES.md for details and instructions how to enable and use.
Roughtime features not implemented by the server:
pool.ntp.org likely will not.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.
Roughenough is copyright (c) 2017-2021 int08h LLC. All rights reserved.
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.