palisade

An HTTP reverse proxy built on hyper, tokio, and rustls. Distributes traffic across weighted upstream backends with active and passive health checks, enforces request policies (header/parameter blocking, body size limits, sensitive data masking), and terminates TLS -- all with streaming I/O and zero per-request allocation for config lookups.

Features

• Weighted round-robin load balancing across multiple upstreams
• Active and passive health checks with configurable thresholds and cooldowns
• TLS termination (HTTPS clients) and TLS origination (HTTPS upstreams) via rustls
• Per-IP rate limiting (GCRA token bucket) with automatic stale-entry cleanup
• Request policy enforcement: header blocking, query parameter blocking, body size limits
• Response body masking of sensitive parameters (passwords, SSNs, etc.)
• Hop-by-hop header stripping and response header removal (e.g. Server, X-Powered-By)
• HTTP request smuggling defense (rejects ambiguous Transfer-Encoding + Content-Length)
• Concurrency limiting with 503 backpressure
• Graceful shutdown with configurable drain timeout
• Structured logging via tracing (pretty or JSON)
• Monotonic X-Request-Id on every response

Quick Start

Prerequisites

• Rust 1.85+ (edition 2024)

Build and Run

git clone https://github.com/kobby-pentangeli/palisade.git
cd palisade
cp Config.example.yml Config.yml   # create your local config
cargo build --release

Edit Config.yml to point at your backend(s), then start the proxy:

cargo run --release
# or run the binary directly:
./target/release/palisade

The proxy listens on 127.0.0.1:8100 by default. Send some requests:

# Basic GET — forwarded to an upstream backend
curl -i http://127.0.0.1:8100/

# POST with a JSON body
curl -i http://127.0.0.1:8100/api/users \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{"name": "alice"}'

# GET with a blocked query parameter (returns 403)
curl -i "http://127.0.0.1:8100/search?access_token=secret"

# GET with a blocked header (returns 403)
curl -i http://127.0.0.1:8100/ -H "X-Debug-Token: abc123"

# Response includes X-Request-Id and stripped internal headers
curl -si http://127.0.0.1:8100/ | grep -i x-request-id

CLI Options

palisade [OPTIONS]

Options:
  -c, --config <PATH>        Path to YAML config file [default: ./Config.yml]
      --log-format <FORMAT>  Log output format: pretty | json [default: pretty]
      --log-level <LEVEL>    Log verbosity, overrides RUST_LOG [e.g. debug, info]
  -h, --help                 Print help
  -V, --version              Print version

Configuration

All configuration lives in a single YAML file. Below is a complete example with defaults shown:

listen: "127.0.0.1:8100"

upstreams:
  - address: "http://localhost:3000"
    weight: 1
  - address: "http://localhost:3001"
    weight: 2

timeouts:
  connect: 5       # seconds
  request: 30      # seconds
  idle: 60         # seconds

pool:
  idle_timeout: 60       # seconds
  max_idle_per_host: 32

max_concurrent_requests: 1000
max_body_size: 10485760  # 10 MiB

blocked_headers:
  - X-Debug-Token
  - X-Internal-Auth

blocked_params:
  - access_token
  - secret_key

masked_params:
  - password
  - ssn
  - credit_card

strip_response_headers:
  - server
  - x-powered-by

health_check:
  path: /health
  interval: 10            # seconds
  unhealthy_threshold: 3
  healthy_threshold: 1
  cooldown: 30            # seconds
  timeout: 3              # seconds

rate_limit:
  requests_per_second: 100
  burst: 50

shutdown_timeout: 30  # seconds

# TLS termination (optional)
# tls:
#   cert_path: /path/to/cert.pem
#   key_path: /path/to/key.pem

All time values are in seconds. Only listen and upstreams are required; everything else has sensible defaults.

Development

cargo build                                                # debug build
cargo test --all-features                                  # run all tests
cargo +nightly fmt                                         # format
cargo clippy --all-features --all-targets -- -D warnings   # lint
cargo build --release --all-features --all-targets         # release build

Contributing

All contributions large and small are actively accepted.

• Read the contribution guidelines.
• Browse Good First Issues.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this codebase by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.