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v0.1.0-rc.
...
b21ee5187d
| Author | SHA1 | Date | |
|---|---|---|---|
| b21ee5187d | |||
| 2726400f5d | |||
| e6ab6fa20d |
@@ -8,8 +8,8 @@ license = "MIT"
|
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[dependencies]
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axum = "0.8"
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tokio = { version = "1", features = ["full"] }
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hickory-proto = "0.25"
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reqwest = { version = "0.12", features = ["rustls-tls"], default-features = false }
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hickory-proto = { version = "0.25", default-features = false, features = ["std"] }
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reqwest = { version = "0.12", default-features = false }
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serde = { version = "1", features = ["derive"] }
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toml = "0.8"
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tracing = "0.1"
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@@ -78,6 +78,12 @@ Before pushing, verify:
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- [ ] No `unwrap()` outside of tests
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- [ ] Config values are externalized (not hardcoded)
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## References
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- [Intra Comparison](docs/intra-comparison.md) — Architectural comparison
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with Jigsaw's Intra, explaining why DNS forwarding alone can't bypass
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censorship and what's needed (TLS splitting, TUN interception, etc.)
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## Milestone Tracking
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See [docs/plan.md](docs/plan.md) for the full project plan and milestone checklist.
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21
LICENSE
Normal file
21
LICENSE
Normal file
@@ -0,0 +1,21 @@
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MIT License
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Copyright (c) 2026 Mohammadreza Khani
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Permission is hereby granted, free of charge, to any person obtaining a copy
|
||||
of this software and associated documentation files (the "Software"), to deal
|
||||
in the Software without restriction, including without limitation the rights
|
||||
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
copies of the Software, and to permit persons to whom the Software is
|
||||
furnished to do so, subject to the following conditions:
|
||||
|
||||
The above copyright notice and this permission notice shall be included in all
|
||||
copies or substantial portions of the Software.
|
||||
|
||||
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||||
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||||
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||||
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||||
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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||||
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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145
README.md
145
README.md
@@ -2,14 +2,18 @@
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A lightweight DNS-over-HTTPS (DoH) forwarder written in Rust.
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Accepts DNS queries over HTTPS ([RFC 8484](https://www.rfc-editor.org/rfc/rfc8484)) and forwards them to upstream DoH resolvers (Cloudflare, Google, Quad9, or custom).
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Accepts DNS queries over traditional DNS (UDP/TCP) and HTTP DoH ([RFC 8484](https://www.rfc-editor.org/rfc/rfc8484)), then forwards them upstream via DoH (HTTPS POST) to configurable resolvers.
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## Why?
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See [docs/story.md](docs/story.md) for the full context — why this exists, what already works, and where this project is headed.
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## Features
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- **Dual-protocol listener** — traditional DNS (UDP/TCP) + HTTP DoH endpoints
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- **RFC 8484 compliant** — GET (`?dns=base64url`) and POST (`application/dns-message`)
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- **Multiple upstreams** — configure several DoH resolvers
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- **Selection strategies** — round-robin or failover
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- **In-memory cache** — TTL-aware with LRU eviction (configurable)
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- **Selection strategies** — round-robin or failover with automatic retry
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- **Environment overrides** — override config via env vars
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- **Graceful shutdown** — handles SIGINT and SIGTERM
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- **Health endpoint** — `GET /health`
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@@ -20,7 +24,7 @@ Accepts DNS queries over HTTPS ([RFC 8484](https://www.rfc-editor.org/rfc/rfc848
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# Build
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cargo build --release
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# Run with default config
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# Run with default config (DoH on :8800, DNS on :53530)
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./target/release/doh-forwarder
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# Run with a custom config
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@@ -29,94 +33,111 @@ cargo build --release
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## Configuration
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Create a TOML config file (see [config/default.toml](config/default.toml)):
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See [config/default.toml](config/default.toml):
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```toml
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[server]
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listen = "0.0.0.0:3000"
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listen = "0.0.0.0:8800"
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[dns]
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listen = "0.0.0.0:53530"
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[upstream]
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resolvers = [
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{ name = "cloudflare", url = "https://cloudflare-dns.com/dns-query" },
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{ name = "google", url = "https://dns.google/dns-query" },
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{ name = "quad9", url = "https://dns.quad9.net/dns-query" },
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]
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strategy = "round-robin" # or "failover"
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[cache]
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enabled = true
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max_entries = 10000
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max_ttl_secs = 3600
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```
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### Environment Variable Overrides
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| Variable | Description | Example |
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|---|---|---|
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| `DOH_LISTEN` | Override server listen address | `0.0.0.0:8080` |
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| `DOH_LISTEN` | Override DoH server listen address | `0.0.0.0:8080` |
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| `DOH_UPSTREAM_STRATEGY` | Override upstream strategy | `failover` |
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| `DOH_UPSTREAM_RESOLVERS` | Comma-separated `name=url` pairs | `google=https://dns.google/dns-query,cf=https://cloudflare-dns.com/dns-query` |
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| `RUST_LOG` | Log level filter | `debug`, `doh_forwarder=trace` |
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## API
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## Usage
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### POST `/dns-query`
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Send a raw DNS wire-format query in the request body.
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### Point your system DNS at the forwarder
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```bash
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# Using a pre-built DNS query (hex-encoded)
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curl -X POST http://localhost:3000/dns-query \
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# /etc/resolv.conf
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nameserver 127.0.0.1
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# Then run the forwarder with [dns] listen = "127.0.0.1:53"
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```
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Or use `resolvectl` with systemd-resolved:
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```bash
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resolvectl dns eth0 127.0.0.1
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resolvectl dns-over-tls no # we handle encryption upstream
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```
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### DoH API
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**POST `/dns-query`** — raw DNS wire-format in body:
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```bash
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curl -X POST http://localhost:8800/dns-query \
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-H "Content-Type: application/dns-message" \
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-H "Accept: application/dns-message" \
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--data-binary @query.bin
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```
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### GET `/dns-query`
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Send a base64url-encoded DNS query as a query parameter.
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**GET `/dns-query`** — base64url-encoded query parameter:
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```bash
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# Encode a DNS query and send via GET
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QUERY=$(python3 -c "
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import base64, struct
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# Minimal A record query for example.com
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q = b'\\x12\\x34' # ID
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q += b'\\x01\\x00' # flags
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q += b'\\x00\\x01' # 1 question
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q += b'\\x00\\x00' # 0 answers
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q += b'\\x00\\x00' # 0 authority
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q += b'\\x00\\x00' # 0 additional
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q += b'\\x07example\\x03com\\x00' # name
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q += b'\\x00\\x01' # type A
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q += b'\\x00\\x01' # class IN
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print(base64.urlsafe_b64encode(q).rstrip(b'=').decode())
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")
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curl "http://localhost:3000/dns-query?dns=$QUERY"
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curl "http://localhost:8800/dns-query?dns=<base64url-encoded-query>"
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```
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### GET `/health`
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Returns `ok` if the server is running.
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**GET `/health`** — returns `ok`:
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```bash
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curl http://localhost:3000/health
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# ok
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curl http://localhost:8800/health
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```
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## Upstream Strategies
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### Upstream Strategies
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| Strategy | Behavior |
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|---|---|
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| `round-robin` | Distributes queries across resolvers in order |
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| `round-robin` | Distributes queries across resolvers in rotation |
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| `failover` | Tries resolvers in order; moves to the next on failure |
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## Project Structure
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```
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doh-forwarder/
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├── Cargo.toml
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├── config/
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│ └── default.toml # Default configuration
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├── docs/
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│ ├── plan.md # Project plan & milestones
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│ └── story.md # Why this project exists
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├── src/
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│ ├── main.rs # Entrypoint, server setup, graceful shutdown
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│ ├── lib.rs # Public API re-exports
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│ ├── config.rs # TOML config + env overrides
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│ ├── routes.rs # HTTP route handlers (/dns-query, /health)
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│ ├── dns/
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│ │ ├── mod.rs
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│ │ ├── query.rs # DNS query parsing
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│ │ ├── response.rs # DNS response building (SERVFAIL)
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│ │ └── listener.rs # UDP/TCP DNS listener
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│ └── upstream/
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│ ├── mod.rs
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│ └── doh_client.rs # DoH forwarding client (retry, strategies)
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├── tests/
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||||
│ └── integration.rs # HTTP integration tests
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└── DEVELOP.md # Development rules & milestone tracking
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||||
```
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## Development
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||||
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||||
```bash
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# Prerequisites
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||||
rustup show # Rust 1.80+
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See [DEVELOP.md](DEVELOP.md) for development rules, coding standards, and milestone tracking.
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```bash
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||||
# Run with auto-reload
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cargo install cargo-watch
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cargo watch -x run
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@@ -129,32 +150,6 @@ cargo clippy -- -D warnings
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cargo fmt --check
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||||
```
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||||
See [DEVELOP.md](DEVELOP.md) for full development rules and milestone tracking.
|
||||
|
||||
## Project Structure
|
||||
|
||||
```
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||||
doh-forwarder/
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||||
├── Cargo.toml
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├── config/
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│ └── default.toml # Default configuration
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├── src/
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||||
│ ├── main.rs # Entrypoint, server setup
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||||
│ ├── lib.rs # Public API re-exports
|
||||
│ ├── config.rs # TOML config + env overrides
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│ ├── cache.rs # DNS response cache (TTL + LRU)
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│ ├── dns/
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│ │ ├── mod.rs
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│ │ ├── query.rs # DNS query parsing
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│ │ └── response.rs # DNS response building
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│ ├── upstream/
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│ │ ├── mod.rs
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│ │ └── doh_client.rs # DoH forwarding client
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│ └── routes.rs # HTTP route handlers
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||||
└── tests/
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||||
└── integration.rs # Integration tests
|
||||
```
|
||||
|
||||
## License
|
||||
|
||||
MIT
|
||||
|
||||
266
docs/intra-comparison.md
Normal file
266
docs/intra-comparison.md
Normal file
@@ -0,0 +1,266 @@
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# doh-forwarder vs Intra — Architectural Comparison
|
||||
|
||||
## Overview
|
||||
|
||||
This document compares **doh-forwarder** (this project) with
|
||||
[Intra](https://github.com/Jigsaw-Code/Intra) by Jigsaw (Google) to
|
||||
understand why Intra can unblock YouTube and other censored sites while
|
||||
doh-forwarder can only resolve their DNS.
|
||||
|
||||
## The Core Problem
|
||||
|
||||
DNS resolution is only the first layer of censorship. Even when DNS is
|
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encrypted and returns the correct IP, the **actual HTTPS connection** to
|
||||
the target server can be blocked by Deep Packet Inspection (DPI) at the
|
||||
TCP/TLS level.
|
||||
|
||||
```
|
||||
doh-forwarder flow:
|
||||
Browser → "youtube.com?" → doh-forwarder → DoH → returns IP ✅
|
||||
Browser → HTTPS to YouTube IP:443 ──────────── BLOCKED by DPI ❌
|
||||
|
||||
Intra flow:
|
||||
Browser → HTTPS to YouTube IP:443 → TUN → Intra split/retry → YouTube ✅
|
||||
```
|
||||
|
||||
## Architectural Differences
|
||||
|
||||
### doh-forwarder — DNS-only forwarder
|
||||
|
||||
```
|
||||
+---------------------+
|
||||
| DNS Client |
|
||||
| (browser, app, OS) |
|
||||
+--------+------------+
|
||||
|
|
||||
+------------+-------------+
|
||||
| |
|
||||
HTTPS (POST/GET) UDP/TCP (port 53)
|
||||
| |
|
||||
v v
|
||||
+-------------------+ +-------------------+
|
||||
| Axum HTTP Server | | DnsListener |
|
||||
| (port 8800) | | (UDP + TCP) |
|
||||
+--------+----------+ +--------+----------+
|
||||
| |
|
||||
+-----------+-------------+
|
||||
|
|
||||
v
|
||||
+-------------------+
|
||||
| DohClient |
|
||||
| (reqwest HTTP) |
|
||||
+--------+----------+
|
||||
|
|
||||
+-----------+-----------+
|
||||
| | |
|
||||
v v v
|
||||
Cloudflare Google Quad9
|
||||
(DoH) (DoH) (DoH)
|
||||
```
|
||||
|
||||
- Accepts DNS queries on port 53 (UDP/TCP) and port 8800 (DoH)
|
||||
- Forwards queries to upstream DoH resolvers over HTTPS
|
||||
- Returns DNS responses to clients
|
||||
- **Does not touch any non-DNS traffic**
|
||||
|
||||
### Intra — Full traffic interception + circumvention
|
||||
|
||||
```
|
||||
+-----------------------------------------------------+
|
||||
| TUN Device |
|
||||
| (captures ALL device traffic) |
|
||||
+---------------------------+--------------------------+
|
||||
|
|
||||
+---------------+----------------+
|
||||
| |
|
||||
DNS packets (port 53) TCP packets (port 443)
|
||||
| |
|
||||
v v
|
||||
+------------------+ +------------------------+
|
||||
| DNS Interception | | intraStreamDialer |
|
||||
| → DoH query via | | → DialWithSplitRetry() |
|
||||
| HTTP POST | | → TLS hello splitting |
|
||||
+------------------+ +------------------------+
|
||||
|
|
||||
+--------+--------+
|
||||
| |
|
||||
Success? Blocked?
|
||||
| |
|
||||
v v
|
||||
Normal TLS Close + retry with
|
||||
handshake split Client Hello
|
||||
```
|
||||
|
||||
- Creates a **TUN device** that captures all device traffic
|
||||
- Intercepts DNS packets → sends via DoH (like doh-forwarder)
|
||||
- Intercepts TCP connections to port 443 → applies circumvention
|
||||
- Uses **TLS Client Hello splitting** to evade DPI
|
||||
|
||||
## Feature Comparison
|
||||
|
||||
| Feature | doh-forwarder | Intra |
|
||||
|---------|:------------:|:-----:|
|
||||
| DNS-over-HTTPS forwarding | ✅ | ✅ |
|
||||
| Multiple upstream resolvers | ✅ | ✅ |
|
||||
| Round-robin / failover | ✅ | ❌ |
|
||||
| UDP + TCP DNS listener | ✅ | ✅ (via TUN) |
|
||||
| HTTP DoH endpoint | ✅ | ❌ |
|
||||
| TUN device (all traffic) | ❌ | ✅ |
|
||||
| TCP stream interception | ❌ | ✅ |
|
||||
| TLS Client Hello splitting | ❌ | ✅ |
|
||||
| Retry on censorship detection | ❌ | ✅ |
|
||||
| SNI-based error reporting | ❌ | ✅ |
|
||||
| EDNS padding | ❌ | ✅ |
|
||||
| IP map with confirmation tracking | ❌ | ✅ |
|
||||
| Servfail hangover (rate limiting) | ❌ | ✅ |
|
||||
| Written in | Rust | Go + Java |
|
||||
| Platform | Linux (server) | Android (VPN) |
|
||||
|
||||
## The Missing Piece: TLS Client Hello Splitting
|
||||
|
||||
The critical technique Intra uses to bypass censorship is **TCP segment
|
||||
splitting** on the TLS Client Hello. Here's how it works:
|
||||
|
||||
### How DPI censorship works
|
||||
|
||||
When your browser connects to `https://www.youtube.com`, the first thing
|
||||
it sends is a **TLS Client Hello** packet. This packet contains the
|
||||
**SNI (Server Name Indication)** field in plaintext — the domain name
|
||||
`www.youtube.com`. A DPI system reads this field and blocks the
|
||||
connection if the domain is on a blocklist.
|
||||
|
||||
### How splitting defeats DPI
|
||||
|
||||
Intra's `splitHello()` function splits the TLS Client Hello into **two
|
||||
TCP segments** at a random offset (6–64 bytes):
|
||||
|
||||
```
|
||||
Normal Client Hello (one TCP segment):
|
||||
[TLS Header (5 bytes)] [SNI: www.youtube.com ... rest of hello]
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
DPI reads this → finds "youtube.com" → BLOCKS
|
||||
|
||||
Split Client Hello (two TCP segments):
|
||||
Segment 1: [TLS Header (5 bytes)] [first N bytes...]
|
||||
Segment 2: [remaining bytes... SNI: www.youtube.com ...]
|
||||
|
||||
DPI can't reassemble fast enough → PASSES THROUGH ✅
|
||||
```
|
||||
|
||||
For TLS Client Hello specifically, Intra also **properly fragments the
|
||||
TLS record header** — it adjusts the record length field in each segment
|
||||
so the TLS layer itself remains valid:
|
||||
|
||||
```go
|
||||
// First segment: adjust record length to split point
|
||||
pkt := hello[:splitLen]
|
||||
binary.BigEndian.PutUint16(pkt[3:5], uint16(recordSplitLen))
|
||||
|
||||
// Second segment: copy TLS header, set remaining length
|
||||
pkt = hello[splitLen-5:]
|
||||
copy(pkt, hello[:5])
|
||||
binary.BigEndian.PutUint16(pkt[3:5], recordLen-uint16(recordSplitLen))
|
||||
```
|
||||
|
||||
### The retry mechanism
|
||||
|
||||
`DialWithSplitRetry()` in `retrier.go`:
|
||||
|
||||
1. Opens a normal TCP connection to the target
|
||||
2. Sends the TLS Client Hello
|
||||
3. Sets a read deadline (1200ms + 2×RTT)
|
||||
4. If the connection is dropped or times out → **censorship detected**
|
||||
5. Closes the connection
|
||||
6. Opens a **new** TCP connection
|
||||
7. Replays the Client Hello as **split segments**
|
||||
8. If this succeeds → the connection proceeds normally
|
||||
|
||||
## Why doh-forwarder Can't Unblock YouTube
|
||||
|
||||
doh-forwarder operates at the **DNS layer only**. It has no visibility
|
||||
into or control over:
|
||||
|
||||
- TCP connections to resolved IPs
|
||||
- TLS handshakes
|
||||
- HTTP requests
|
||||
|
||||
The traffic flow is:
|
||||
|
||||
```
|
||||
1. Browser asks OS: "What's the IP for youtube.com?"
|
||||
2. OS sends DNS query to doh-forwarder (port 53)
|
||||
3. doh-forwarder forwards via DoH → gets correct IP (e.g., 142.250.80.46)
|
||||
4. Browser connects directly to 142.250.80.46:443
|
||||
5. Browser sends TLS Client Hello with SNI=www.youtube.com
|
||||
6. ISP's DPI reads SNI → blocks connection
|
||||
7. Browser shows "connection timed out" or "connection reset"
|
||||
```
|
||||
|
||||
Step 4–7 happen entirely outside doh-forwarder's scope.
|
||||
|
||||
## What Would Be Needed
|
||||
|
||||
To achieve what Intra does, doh-forwarder would need to evolve from a
|
||||
DNS forwarder into a **traffic interception and circumvention proxy**:
|
||||
|
||||
### Option A: SOCKS5 Proxy with Split Transport (M6 path)
|
||||
|
||||
```
|
||||
Browser → SOCKS5 proxy (doh-forwarder) → split TCP → target server
|
||||
```
|
||||
|
||||
- Configure browser to use SOCKS5 proxy
|
||||
- Proxy applies TLS splitting on outbound connections
|
||||
- Lighter than full TUN, requires browser config
|
||||
|
||||
### Option B: Transparent Proxy with TUN (Intra-like)
|
||||
|
||||
```
|
||||
All traffic → TUN device → doh-forwarder → DNS: DoH / TCP: split → target
|
||||
```
|
||||
|
||||
- Zero browser configuration
|
||||
- Requires root/CAP_NET_ADMIN for TUN
|
||||
- Significantly more complex
|
||||
|
||||
### Option C: Hybrid
|
||||
|
||||
- DNS forwarding via DoH (current functionality)
|
||||
- Optional SOCKS5 proxy for TCP circumvention
|
||||
- Optional TUN mode for transparent interception
|
||||
- User chooses based on their environment
|
||||
|
||||
## Lessons from Intra's Codebase
|
||||
|
||||
### 1. IP Map with Confirmation Tracking
|
||||
|
||||
Intra maintains an `ipmap` that tracks which IPs of a DoH resolver
|
||||
actually work. If a confirmed IP starts failing, it's disconfirmed and
|
||||
alternatives are tried. This provides resilience against partial IP
|
||||
blocking.
|
||||
|
||||
### 2. EDNS Padding
|
||||
|
||||
Intra pads DNS queries to standard sizes to prevent traffic analysis
|
||||
that could identify specific domains by query size.
|
||||
|
||||
### 3. Servfail Hangover
|
||||
|
||||
When a DoH server returns errors, Intra enters a 10-second "hangover"
|
||||
where it stops sending queries (returns SERVFAIL immediately). This
|
||||
rate-limits queries to misconfigured or blocked servers.
|
||||
|
||||
### 4. SNI Reporter
|
||||
|
||||
Intra reports which SNIs are being censored (via the Choir library) to
|
||||
contribute to censorship monitoring without revealing individual user
|
||||
activity.
|
||||
|
||||
## References
|
||||
|
||||
- [Intra source code](https://github.com/Jigsaw-Code/Intra)
|
||||
- [Outline SDK](https://github.com/Jigsaw-Code/outline-sdk) — the
|
||||
transport library Intra uses
|
||||
- [RFC 8484 — DNS over HTTPS](https://tools.ietf.org/html/rfc8484)
|
||||
- [TLS Client Hello splitting](https://gfw.report/talks/syria2016/en/)
|
||||
— research on DPI evasion
|
||||
140
docs/story.md
Normal file
140
docs/story.md
Normal file
@@ -0,0 +1,140 @@
|
||||
# The Story — Why This Project Exists
|
||||
|
||||
## The Problem
|
||||
|
||||
In countries with internet censorship (Iran, China, Russia, and others), DNS is
|
||||
one of the first things controlled. ISPs intercept plain DNS queries (UDP/TCP
|
||||
port 53) and:
|
||||
|
||||
- Return fake IP addresses for blocked domains
|
||||
- Log every domain you look up
|
||||
- Inject ads or redirect to government portals
|
||||
|
||||
DNS-over-HTTPS (DoH) and DNS-over-TLS (DoT) solve this by encrypting DNS
|
||||
queries, making them invisible to the ISP's DNS layer.
|
||||
|
||||
## What Already Exists
|
||||
|
||||
This is not a new problem. Mature tools already solve local DNS → DoH forwarding:
|
||||
|
||||
| Tool | What it does | Maintained by |
|
||||
|---|---|---|
|
||||
| `cloudflared` | Local DNS → DoH proxy (`cloudflared proxy-dns`) | Cloudflare |
|
||||
| `dnscrypt-proxy` | DoH + DoT + anonymized relays, blocklists | Frank Denis |
|
||||
| `stubby` | Local DNS → DoT proxy | getdns team |
|
||||
| `systemd-resolved` | Built into systemd, supports DoT | systemd team |
|
||||
| `AdGuard Home` | DNS proxy + DoH/DoT + web UI + blocklists | AdGuard |
|
||||
|
||||
For simple "local DNS → DoH" forwarding, **`cloudflared proxy-dns` does exactly
|
||||
what this project does in one command:**
|
||||
|
||||
```bash
|
||||
cloudflared proxy-dns --port 5353 --upstream https://cloudflare-dns.com/dns-query
|
||||
```
|
||||
|
||||
## The Real Obstacle
|
||||
|
||||
The harder problem — and the one most relevant to censored regions — is that
|
||||
**upstream DoH/DoT endpoints themselves get blocked:**
|
||||
|
||||
| Technique | What gets blocked | How |
|
||||
|---|---|---|
|
||||
| SNI inspection | `cloudflare-dns.com`, `dns.google` | TLS ClientHello reveals the domain |
|
||||
| IP blocklist | Known resolver IPs (1.1.1.1, 8.8.8.8) | Direct IP blocking |
|
||||
| TLS fingerprinting | DoH/DoT traffic patterns | JA3/JA4 fingerprint analysis |
|
||||
| Deep packet inspection | HTTPS traffic to known DNS resolvers | Pattern matching on domain + path |
|
||||
|
||||
A local forwarder that sends `POST https://cloudflare-dns.com/dns-query` will
|
||||
work in most of the world, but **will likely fail in Iran** because the
|
||||
connection to Cloudflare itself is blocked.
|
||||
|
||||
## What Actually Works in Censored Environments
|
||||
|
||||
Tools that solve the **upstream blocking** problem:
|
||||
|
||||
1. **Warp / WireGuard** — tunnel all traffic (including DNS) through an
|
||||
encrypted VPN. The ISP sees WireGuard traffic but can't inspect it.
|
||||
|
||||
2. **GoodbyeDPI / zapret** — packet manipulation to evade DPI without a VPN.
|
||||
Modifies TCP flags, splits packets, fakes SNI.
|
||||
|
||||
3. **dnscrypt-proxy with anonymized relays** — DNS queries go through
|
||||
intermediate relays. The resolver never sees your IP, and the ISP never
|
||||
sees the resolver's IP.
|
||||
|
||||
4. **Tor** — route DNS through Tor exit nodes. Slow but highly resistant.
|
||||
|
||||
5. **Encrypted Client Hello (ECH)** — hides the SNI field in TLS handshakes.
|
||||
Still emerging; not widely supported.
|
||||
|
||||
## So Is This Project Necessary?
|
||||
|
||||
**Honestly: no, not for its current functionality.**
|
||||
|
||||
If the goal is "use encrypted DNS from Linux in a censored region," install
|
||||
`cloudflared` or `dnscrypt-proxy` + a Warp/WireGuard tunnel. These are
|
||||
battle-tested, maintained by teams, and packaged in every distro.
|
||||
|
||||
## Where This Project Becomes Useful
|
||||
|
||||
This project becomes **genuinely valuable** if it evolves beyond a basic
|
||||
forwarder. Directions that matter:
|
||||
|
||||
### 1. Upstream obfuscation (the real differentiator)
|
||||
|
||||
Route upstream DoH traffic through a proxy (SOCKS5, HTTP CONNECT, or
|
||||
WireGuard tunnel) instead of direct HTTPS. This bypasses SNI and IP
|
||||
blocking:
|
||||
|
||||
```
|
||||
Local DNS → this forwarder → SOCKS5 proxy → DoH resolver
|
||||
```
|
||||
|
||||
No existing lightweight Rust tool does this well. `dnscrypt-proxy` has
|
||||
anonymized relays but no SOCKS5 support for DoH.
|
||||
|
||||
### 2. Pluggable transport layer
|
||||
|
||||
Support multiple upstream transports:
|
||||
- **Direct DoH** (current — works in free internet)
|
||||
- **DoH over SOCKS5** (works behind blocks)
|
||||
- **DoH over WireGuard tunnel** (works behind aggressive DPI)
|
||||
- **DNS-over-TLS** (for resolvers that support it)
|
||||
|
||||
The user picks the transport based on their environment.
|
||||
|
||||
### 3. Smart upstream selection
|
||||
|
||||
Don't just round-robin — **probe** upstreams for latency and availability.
|
||||
Auto-switch when a resolver becomes unreachable. This matters when resolvers
|
||||
get blocked intermittently.
|
||||
|
||||
### 4. Built-in blocklist support
|
||||
|
||||
Ad-blocking and malware-blocking at the DNS level. `dnscrypt-proxy` and
|
||||
`AdGuard Home` do this, but a lightweight Rust binary with this built-in
|
||||
is appealing for embedded/resource-constrained systems.
|
||||
|
||||
### 5. Learning
|
||||
|
||||
Even if you never deploy it, building this teaches:
|
||||
- DNS wire format (RFC 1035)
|
||||
- DoH protocol (RFC 8484)
|
||||
- Rust async (Tokio, Axum)
|
||||
- Network programming
|
||||
- Error handling patterns
|
||||
|
||||
That alone justifies the project.
|
||||
|
||||
## Summary
|
||||
|
||||
| Question | Answer |
|
||||
|---|---|
|
||||
| Does this solve local DNS → DoH? | Yes, but `cloudflared` already does this |
|
||||
| Does this bypass censorship? | No — upstream DoH endpoints get blocked |
|
||||
| Is the project pointless? | No — it's a foundation for something better |
|
||||
| What makes it worth building? | SOCKS5/proxy upstream support, pluggable transports, learning |
|
||||
|
||||
The project is a **starting point**, not a finished solution. The first 80%
|
||||
(local DNS → DoH forwarding) is solved by existing tools. The last 20%
|
||||
(bypassing upstream blocking) is where this project can differentiate.
|
||||
@@ -4,12 +4,12 @@ pkgver=0.1.0
|
||||
pkgrel=1
|
||||
pkgdesc="A lightweight DNS-over-HTTPS forwarder"
|
||||
arch=('x86_64')
|
||||
url="https://gitea.logi.camp/LogiCrew/doh-forwarder"
|
||||
url="https://git.logicamp.dev/mohamad/doh-forwarder"
|
||||
license=('MIT')
|
||||
depends=('gcc-libs')
|
||||
depends=('gcc-libs' 'openssl')
|
||||
makedepends=('rust' 'cargo')
|
||||
backup=('etc/doh-forwarder/config.toml')
|
||||
source=("$pkgname-$pkgver.tar.gz::https://git.logicamp.dev/LogiCrew/doh-forwarder/archive/v${pkgver}.tar.gz"
|
||||
source=("$pkgname::git+https://git.logicamp.dev/mohamad/doh-forwarder.git#tag=v${pkgver}"
|
||||
'doh-forwarder.service'
|
||||
'doh-forwarder.sysusers'
|
||||
'doh-forwarder.conf')
|
||||
@@ -20,12 +20,12 @@ sha256sums=('SKIP'
|
||||
|
||||
build() {
|
||||
cd "$pkgname"
|
||||
cargo build --release --locked
|
||||
cargo build --release
|
||||
}
|
||||
|
||||
check() {
|
||||
cd "$pkgname"
|
||||
cargo test --release --locked
|
||||
cargo test --release
|
||||
}
|
||||
|
||||
package() {
|
||||
|
||||
Reference in New Issue
Block a user