chore: Release bore-cli version 0.5.0

* Use random ports when port number is 0

* Add support for --max-port CLI option

* Fix typo

* Fix another typo

* Update README

.dockerignore

@@ -0,0 +1 @@
+/target

.github/FUNDING.yml

@@ -0,0 +1 @@
+github: [ekzhang]

.github/workflows/ci.yml

@@ -1,6 +1,6 @@
 name: CI
 
-on: push
+on: [push, pull_request]
 
 jobs:
   rust:
@@ -44,4 +44,4 @@ jobs:
           toolchain: stable
           components: clippy
 
-      - run: cargo clippy
+      - run: cargo clippy -- -D warnings

.github/workflows/docker.yml

@@ -0,0 +1,51 @@
+name: Docker
+
+on:
+  push:
+    tags:
+      - "v*.*.*"
+
+jobs:
+  build_deploy:
+    name: Build and Deploy
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          images: ekzhang/bore
+          tags: |
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+        with:
+          platforms: arm64
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push
+        id: docker_build
+        uses: docker/build-push-action@v3
+        with:
+          # This doesn't work now because of an issue in multi-platform Docker builds.
+          #   -> see https://github.com/rust-lang/rust/issues/97520
+          # platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+
+      - name: Image digest
+        run: echo ${{ steps.docker_build.outputs.digest }}

.github/workflows/mean_bean_ci.yml

@@ -0,0 +1,123 @@
+name: Mean Bean CI
+
+on: [push, pull_request]
+
+jobs:
+  install-cross:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+        with:
+          fetch-depth: 50
+
+      - uses: XAMPPRocky/get-github-release@v1
+        id: cross
+        with:
+          owner: rust-embedded
+          repo: cross
+          matches: ${{ matrix.platform }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - uses: actions/upload-artifact@v1
+        with:
+          name: cross-${{ matrix.platform }}
+          path: ${{ steps.cross.outputs.install_path }}
+    strategy:
+      matrix:
+        platform: [linux-musl]
+
+  macos:
+    runs-on: macos-latest
+    strategy:
+      fail-fast: true
+      matrix:
+        channel: [stable]
+        target:
+          - x86_64-apple-darwin
+
+    steps:
+      - name: Setup | Checkout
+        uses: actions/checkout@v2
+      - name: Setup | Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+          profile: minimal
+          target: ${{ matrix.target }}
+      - run: ci/set_rust_version.bash ${{ matrix.channel }} ${{ matrix.target }}
+      - name: Test
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --target ${{ matrix.target }}
+          use-cross: false
+
+  linux:
+    runs-on: ubuntu-latest
+    needs: install-cross
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 50
+
+      - name: Download Cross
+        uses: actions/download-artifact@v1
+        with:
+          name: cross-linux-musl
+          path: /tmp/
+      - run: chmod +x /tmp/cross
+      - run: ci/set_rust_version.bash ${{ matrix.channel }} ${{ matrix.target }}
+      - run: ci/build.bash /tmp/cross ${{ matrix.target }}
+        # These targets have issues with being tested so they are disabled
+        # by default. You can try disabling to see if they work for
+        # your project.
+      - run: ci/test.bash /tmp/cross ${{ matrix.target }}
+        if: |
+          !contains(matrix.target, 'android') &&
+          !contains(matrix.target, 'bsd') &&
+          !contains(matrix.target, 'solaris') &&
+          matrix.target != 'armv5te-unknown-linux-musleabi' &&
+          matrix.target != 'sparc64-unknown-linux-gnu'
+
+    strategy:
+      fail-fast: true
+      matrix:
+        channel: [stable]
+        target:
+          - arm-unknown-linux-gnueabi
+          - armv7-unknown-linux-gnueabihf
+          - i686-unknown-linux-musl
+          - x86_64-unknown-linux-musl
+
+  windows:
+    runs-on: windows-latest
+    # Windows technically doesn't need this, but if we don't block windows on it
+    # some of the windows jobs could fill up the concurrent job queue before
+    # one of the install-cross jobs has started, so this makes sure all
+    # artifacts are downloaded first.
+    needs: install-cross
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 50
+      - run: ci/set_rust_version.bash ${{ matrix.channel }} ${{ matrix.target }}
+        shell: bash
+      - run: ci/build.bash cargo ${{ matrix.target }}
+        shell: bash
+      - run: ci/test.bash cargo ${{ matrix.target }}
+        shell: bash
+
+    strategy:
+      fail-fast: true
+      matrix:
+        channel: [stable]
+        target:
+          # MSVC
+          - i686-pc-windows-msvc
+          - x86_64-pc-windows-msvc
+          # GNU: You typically only need to test Windows GNU if you're
+          # specifically targetting it, and it can cause issues with some
+          # dependencies if you're not so it's disabled by self.
+          # - i686-pc-windows-gnu
+          # - x86_64-pc-windows-gnu

.github/workflows/mean_bean_deploy.yml

@@ -0,0 +1,192 @@
+on:
+  push:
+    # # Sequence of patterns matched against refs/tags
+    tags:
+      - "v*" # Push events to matching v*, i.e. v1.0, v20.15.10
+
+name: Mean Bean Deploy
+env:
+  BIN: bore
+
+jobs:
+  # This job downloads and stores `cross` as an artifact, so that it can be
+  # redownloaded across all of the jobs. Currently this copied pasted between
+  # `mean_bean_ci.yml` and `mean_bean_deploy.yml`. Make sure to update both places when making
+  # changes.
+  install-cross:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+        with:
+          fetch-depth: 50
+
+      - uses: XAMPPRocky/get-github-release@v1
+        id: cross
+        with:
+          owner: rust-embedded
+          repo: cross
+          matches: ${{ matrix.platform }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - uses: actions/upload-artifact@v1
+        with:
+          name: cross-${{ matrix.platform }}
+          path: ${{ steps.cross.outputs.install_path }}
+    strategy:
+      matrix:
+        platform: [linux-musl]
+
+  macos:
+    runs-on: macos-latest
+    strategy:
+      matrix:
+        target:
+          # macOS
+          - x86_64-apple-darwin
+          - aarch64-apple-darwin
+    steps:
+      - name: Get tag
+        id: tag
+        uses: dawidd6/action-get-tag@v1
+
+      - name: Setup | Checkout
+        uses: actions/checkout@v2
+
+      # Cache files between builds
+      - name: Setup | Cache Cargo
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}-${{ matrix.target }}
+
+      - name: Setup | Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+          profile: minimal
+          target: ${{ matrix.target }}
+
+      - name: Build | Build
+        uses: actions-rs/cargo@v1
+        with:
+          command: build
+          args: --release --target ${{ matrix.target }}
+
+      - run: tar -czvf ${{ env.BIN }}.tar.gz --directory=target/${{ matrix.target }}/release ${{ env.BIN }}
+      - uses: XAMPPRocky/create-release@v1.0.2
+        id: create_release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          draft: false
+          prerelease: false
+
+      - uses: actions/upload-release-asset@v1
+        id: upload-release-asset
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: ${{ env.BIN }}.tar.gz
+          asset_name: ${{ env.BIN }}-${{steps.tag.outputs.tag}}-${{ matrix.target }}.tar.gz
+          asset_content_type: application/gzip
+
+  linux:
+    runs-on: ubuntu-latest
+    needs: install-cross
+    strategy:
+      matrix:
+        target:
+          - arm-unknown-linux-gnueabi
+          - armv7-unknown-linux-gnueabihf
+          - i686-unknown-linux-musl
+          - x86_64-unknown-linux-musl
+    steps:
+      - name: Get tag
+        id: tag
+        uses: dawidd6/action-get-tag@v1
+
+      - uses: actions/checkout@v2
+      - uses: actions/download-artifact@v1
+        with:
+          name: cross-linux-musl
+          path: /tmp/
+      - run: chmod +x /tmp/cross
+
+      - run: ci/set_rust_version.bash stable ${{ matrix.target }}
+      - run: ci/build.bash /tmp/cross ${{ matrix.target }} RELEASE
+      - run: tar -czvf ${{ env.BIN }}.tar.gz --directory=target/${{ matrix.target }}/release ${{ env.BIN }}
+
+      - uses: XAMPPRocky/create-release@v1.0.2
+        id: create_release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          draft: false
+          prerelease: false
+
+      - name: Upload Release Asset
+        id: upload-release-asset
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: ${{ env.BIN }}.tar.gz
+          asset_name: ${{ env.BIN }}-${{steps.tag.outputs.tag}}-${{ matrix.target }}.tar.gz
+          asset_content_type: application/gzip
+
+  windows:
+    runs-on: windows-latest
+    needs: install-cross
+    strategy:
+      matrix:
+        target:
+          # MSVC
+          - i686-pc-windows-msvc
+          - x86_64-pc-windows-msvc
+          # GNU
+          # - i686-pc-windows-gnu
+          # - x86_64-pc-windows-gnu
+    steps:
+      - name: Get tag
+        id: tag
+        uses: dawidd6/action-get-tag@v1
+
+      - uses: actions/checkout@v2
+      - run: bash ci/set_rust_version.bash stable ${{ matrix.target }}
+      - run: bash ci/build.bash cargo ${{ matrix.target }} RELEASE
+      - run: |
+          cd ./target/${{ matrix.target }}/release/
+          7z a "${{ env.BIN }}.zip" "${{ env.BIN }}.exe"
+          mv "${{ env.BIN }}.zip" $GITHUB_WORKSPACE
+        shell: bash
+        # We're using using a fork of `actions/create-release` that detects
+        # whether a release is already available or not first.
+      - uses: XAMPPRocky/create-release@v1.0.2
+        id: create_release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          # Draft should **always** be false. GitHub doesn't provide a way to
+          # get draft releases from its API, so there's no point using it.
+          draft: false
+          prerelease: false
+      - uses: actions/upload-release-asset@v1
+        id: upload-release-asset
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: ${{ env.BIN }}.zip
+          asset_name: ${{ env.BIN }}-${{steps.tag.outputs.tag}}-${{ matrix.target }}.zip
+          asset_content_type: application/zip

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "bore-cli"
-version = "0.2.0"
+version = "0.5.0"
 authors = ["Eric Zhang <ekzhang1@gmail.com>"]
 license = "MIT"
 description = "A modern, simple TCP tunnel in Rust that exposes local ports to a remote server, bypassing standard NAT connection firewalls."
@@ -17,14 +17,22 @@ path = "src/main.rs"
 
 [dependencies]
 anyhow = { version = "1.0.56", features = ["backtrace"] }
-clap = { version = "3.1.8", features = ["derive"] }
+clap = { version = "4.0.22", features = ["derive", "env"] }
 dashmap = "5.2.0"
+fastrand = "1.9.0"
+futures-util = { version = "0.3.21", features = ["sink"] }
 hex = "0.4.3"
 hmac = "0.12.1"
 serde = { version = "1.0.136", features = ["derive"] }
 serde_json = "1.0.79"
 sha2 = "0.10.2"
-tokio = { version = "1.17.0", features = ["full"] }
+tokio = { version = "1.17.0", features = ["rt-multi-thread", "io-util", "macros", "net", "time"] }
+tokio-util = { version = "0.7.1", features = ["codec"] }
 tracing = "0.1.32"
 tracing-subscriber = "0.3.10"
-uuid = { version = "0.8.2", features = ["serde", "v4"] }
+uuid = { version = "1.2.1", features = ["serde", "v4"] }
+
+[dev-dependencies]
+lazy_static = "1.4.0"
+rstest = "0.15.0"
+tokio = { version = "1.17.0", features = ["sync"] }

Dockerfile

@@ -0,0 +1,10 @@
+FROM rust:alpine as builder
+WORKDIR /home/rust/src
+RUN apk --no-cache add musl-dev
+COPY . .
+RUN cargo install --path .
+
+FROM scratch
+COPY --from=builder /usr/local/cargo/bin/bore .
+USER 1000:1000
+ENTRYPOINT ["./bore"]

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 Eric Zhang
+
+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,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,6 +1,6 @@
 # bore
 
-[![Build status](https://img.shields.io/github/workflow/status/ekzhang/bore/CI)](https://github.com/ekzhang/bore/actions)
+[![Build status](https://img.shields.io/github/actions/workflow/status/ekzhang/bore/ci.yml)](https://github.com/ekzhang/bore/actions)
 [![Crates.io](https://img.shields.io/crates/v/bore-cli.svg)](https://crates.io/crates/bore-cli)
 
 A modern, simple TCP tunnel in Rust that exposes local ports to a remote server, bypassing standard NAT connection firewalls. **That's all it does: no more, and no less.**
@@ -8,7 +8,7 @@ A modern, simple TCP tunnel in Rust that exposes local ports to a remote server,
 ![Video demo](https://i.imgur.com/vDeGsmx.gif)
 
 ```shell
-# Installation (requires Rust)
+# Installation (requires Rust, see alternatives below)
 cargo install bore-cli
 
 # On your local machine
@@ -19,7 +19,29 @@ This will expose your local port at `localhost:8000` to the public internet at `
 
 Similar to [localtunnel](https://github.com/localtunnel/localtunnel) and [ngrok](https://ngrok.io/), except `bore` is intended to be a highly efficient, unopinionated tool for forwarding TCP traffic that is simple to install and easy to self-host, with no frills attached.
 
-(`bore` totals less than 400 lines of safe, async Rust code and is trivial to set up — just run a single binary for the client and server.)
+(`bore` totals about 400 lines of safe, async Rust code and is trivial to set up — just run a single binary for the client and server.)
+
+## Installation
+
+If you're on macOS, `bore` is packaged as a Homebrew formula.
+
+```shell
+brew install ekzhang/bore/bore
+```
+
+Otherwise, the easiest way to install bore is from prebuilt binaries. These are available on the [releases page](https://github.com/ekzhang/bore/releases) for macOS, Windows, and Linux. Just unzip the appropriate file for your platform and move the `bore` executable into a folder on your PATH.
+
+You also can build `bore` from source using [Cargo](https://doc.rust-lang.org/cargo/), the Rust package manager. This command installs the `bore` binary at a user-accessible path.
+
+```shell
+cargo install bore-cli
+```
+
+We also publish versioned Docker images for each release. The image is built for an AMD 64-bit architecture. They're tagged with the specific version and allow you to run the statically-linked `bore` binary from a minimal "scratch" container.
+
+```shell
+docker run -it --init --rm --network host ekzhang/bore <ARGS>
+```
 
 ## Detailed Usage
 
@@ -33,31 +55,29 @@ You can forward a port on your local machine by using the `bore local` command.
 bore local 5000 --to bore.pub
 ```
 
-You can optionally pass in a `--port` option to pick a specific port on the remote to expose, although the command will fail if this port is not available.
+You can optionally pass in a `--port` option to pick a specific port on the remote to expose, although the command will fail if this port is not available. Also, passing `--local-host` allows you to expose a different host on your local area network besides the loopback address `localhost`.
 
 The full options are shown below.
 
 ```shell
-bore-local 0.2.0
 Starts a local proxy to the remote server
 
-USAGE:
-    bore local [OPTIONS] --to <TO> <LOCAL_PORT>
+Usage: bore local [OPTIONS] --to <TO> <LOCAL_PORT>
 
-ARGS:
-    <LOCAL_PORT>    The local port to listen on
+Arguments:
+  <LOCAL_PORT>  The local port to expose
 
-OPTIONS:
-    -h, --help               Print help information
-    -p, --port <PORT>        Optional port on the remote server to select [default: 0]
-    -s, --secret <SECRET>    Optional secret for authentication
-    -t, --to <TO>            Address of the remote server to expose local ports to
-    -V, --version            Print version information
+Options:
+  -l, --local-host <HOST>  The local host to expose [default: localhost]
+  -t, --to <TO>            Address of the remote server to expose local ports to [env: BORE_SERVER=]
+  -p, --port <PORT>        Optional port on the remote server to select [default: 0]
+  -s, --secret <SECRET>    Optional secret for authentication [env: BORE_SECRET]
+  -h, --help               Print help information
 ```
 
 ### Self-Hosting
 
-As mentioned in the startup instructions, there is an public instance of the `bore` server running at `bore.pub`. However, if you want to self-host `bore` on your own network, you can do so with the following command:
+As mentioned in the startup instructions, there is a public instance of the `bore` server running at `bore.pub`. However, if you want to self-host `bore` on your own network, you can do so with the following command:
 
 ```shell
 bore server
@@ -68,17 +88,15 @@ That's all it takes! After the server starts running at a given address, you can
 The full options for the `bore server` command are shown below.
 
 ```shell
-bore-server 0.2.0
 Runs the remote proxy server
 
-USAGE:
-    bore server [OPTIONS]
+Usage: bore server [OPTIONS]
 
-OPTIONS:
-    -h, --help                   Print help information
-        --min-port <MIN_PORT>    Minimum TCP port number to accept [default: 1024]
-    -s, --secret <SECRET>        Optional secret for authentication
-    -V, --version                Print version information
+Options:
+      --min-port <MIN_PORT>  Minimum accepted TCP port number [default: 1024]
+      --max-port <MAX_PORT>  Maximum accepted TCP port number [default: 65535]
+  -s, --secret <SECRET>      Optional secret for authentication [env: BORE_SECRET]
+  -h, --help                 Print help information
 ```
 
 ## Protocol
@@ -101,6 +119,8 @@ bore server --secret my_secret_string
 bore local <LOCAL_PORT> --to <TO> --secret my_secret_string
 ```
 
+If a secret is not present in the arguments, `bore` will also attempt to read from the `BORE_SECRET` environment variable.
+
 ## Acknowledgements
 
 Created by Eric Zhang ([@ekzhang1](https://twitter.com/ekzhang1)). Licensed under the [MIT license](LICENSE).

ci/build.bash

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+# Script for building your rust projects.
+set -e
+
+source ci/common.bash
+
+# $1 {path} = Path to cross/cargo executable
+CROSS=$1
+# $1 {string} = <Target Triple> e.g. x86_64-pc-windows-msvc
+TARGET_TRIPLE=$2
+# $3 {boolean} = Are we building for deployment? 
+RELEASE_BUILD=$3
+
+required_arg $CROSS 'CROSS'
+required_arg $TARGET_TRIPLE '<Target Triple>'
+
+if [ -z "$RELEASE_BUILD" ]; then
+    $CROSS build --target $TARGET_TRIPLE
+    $CROSS build --target $TARGET_TRIPLE --all-features
+else
+    $CROSS build --target $TARGET_TRIPLE --all-features --release
+fi

ci/common.bash

@@ -0,0 +1,6 @@
+required_arg() {
+    if [ -z "$1" ]; then
+        echo "Required argument $2 missing"
+        exit 1
+    fi
+}

ci/set_rust_version.bash

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+set -e
+rustup default $1
+rustup target add $2

ci/test.bash

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+# Script for building your rust projects.
+set -e
+
+source ci/common.bash
+
+# $1 {path} = Path to cross/cargo executable
+CROSS=$1
+# $1 {string} = <Target Triple>
+TARGET_TRIPLE=$2
+
+required_arg $CROSS 'CROSS'
+required_arg $TARGET_TRIPLE '<Target Triple>'
+
+$CROSS test --target $TARGET_TRIPLE
+$CROSS test --target $TARGET_TRIPLE --all-features

src/auth.rs

@@ -3,10 +3,10 @@
 use anyhow::{bail, ensure, Result};
 use hmac::{Hmac, Mac};
 use sha2::{Digest, Sha256};
-use tokio::io::{AsyncBufRead, AsyncWrite};
+use tokio::io::{AsyncRead, AsyncWrite};
 use uuid::Uuid;
 
-use crate::shared::{recv_json, send_json, ClientMessage, ServerMessage};
+use crate::shared::{ClientMessage, Delimited, ServerMessage};
 
 /// Wrapper around a MAC used for authenticating clients that have a secret.
 pub struct Authenticator(Hmac<Sha256>);
@@ -48,13 +48,13 @@ impl Authenticator {
     }
 
     /// As the server, send a challenge to the client and validate their response.
-    pub async fn server_handshake(
+    pub async fn server_handshake<T: AsyncRead + AsyncWrite + Unpin>(
         &self,
-        stream: &mut (impl AsyncBufRead + AsyncWrite + Unpin),
+        stream: &mut Delimited<T>,
     ) -> Result<()> {
         let challenge = Uuid::new_v4();
-        send_json(stream, ServerMessage::Challenge(challenge)).await?;
-        match recv_json(stream, &mut Vec::new()).await? {
+        stream.send(ServerMessage::Challenge(challenge)).await?;
+        match stream.recv_timeout().await? {
             Some(ClientMessage::Authenticate(tag)) => {
                 ensure!(self.validate(&challenge, &tag), "invalid secret");
                 Ok(())
@@ -64,16 +64,16 @@ impl Authenticator {
     }
 
     /// As the client, answer a challenge to attempt to authenticate with the server.
-    pub async fn client_handshake(
+    pub async fn client_handshake<T: AsyncRead + AsyncWrite + Unpin>(
         &self,
-        stream: &mut (impl AsyncBufRead + AsyncWrite + Unpin),
+        stream: &mut Delimited<T>,
     ) -> Result<()> {
-        let challenge = match recv_json(stream, &mut Vec::new()).await? {
+        let challenge = match stream.recv_timeout().await? {
             Some(ServerMessage::Challenge(challenge)) => challenge,
             _ => bail!("expected authentication challenge, but no secret was required"),
         };
         let tag = self.answer(&challenge);
-        send_json(stream, ClientMessage::Authenticate(tag)).await?;
+        stream.send(ClientMessage::Authenticate(tag)).await?;
         Ok(())
     }
 }

src/client.rs

@@ -3,21 +3,26 @@
 use std::sync::Arc;
 
 use anyhow::{bail, Context, Result};
-use tokio::{io::BufReader, net::TcpStream};
+use tokio::{io::AsyncWriteExt, net::TcpStream, time::timeout};
 use tracing::{error, info, info_span, warn, Instrument};
 use uuid::Uuid;
 
 use crate::auth::Authenticator;
-use crate::shared::{proxy, recv_json, send_json, ClientMessage, ServerMessage, CONTROL_PORT};
+use crate::shared::{
+    proxy, ClientMessage, Delimited, ServerMessage, CONTROL_PORT, NETWORK_TIMEOUT,
+};
 
 /// State structure for the client.
 pub struct Client {
     /// Control connection to the server.
-    conn: Option<BufReader<TcpStream>>,
+    conn: Option<Delimited<TcpStream>>,
 
     /// Destination address of the server.
     to: String,
 
+    // Local host that is forwarded.
+    local_host: String,
+
     /// Local port that is forwarded.
     local_port: u16,
 
@@ -30,19 +35,21 @@ pub struct Client {
 
 impl Client {
     /// Create a new client.
-    pub async fn new(local_port: u16, to: &str, port: u16, secret: Option<&str>) -> Result<Self> {
-        let stream = TcpStream::connect((to, CONTROL_PORT))
-            .await
-            .with_context(|| format!("could not connect to {to}:{CONTROL_PORT}"))?;
-        let mut stream = BufReader::new(stream);
-
+    pub async fn new(
+        local_host: &str,
+        local_port: u16,
+        to: &str,
+        port: u16,
+        secret: Option<&str>,
+    ) -> Result<Self> {
+        let mut stream = Delimited::new(connect_with_timeout(to, CONTROL_PORT).await?);
         let auth = secret.map(Authenticator::new);
         if let Some(auth) = &auth {
             auth.client_handshake(&mut stream).await?;
         }
 
-        send_json(&mut stream, ClientMessage::Hello(port)).await?;
-        let remote_port = match recv_json(&mut stream, &mut Vec::new()).await? {
+        stream.send(ClientMessage::Hello(port)).await?;
+        let remote_port = match stream.recv_timeout().await? {
             Some(ServerMessage::Hello(remote_port)) => remote_port,
             Some(ServerMessage::Error(message)) => bail!("server error: {message}"),
             Some(ServerMessage::Challenge(_)) => {
@@ -57,6 +64,7 @@ impl Client {
         Ok(Client {
             conn: Some(stream),
             to: to.to_string(),
+            local_host: local_host.to_string(),
             local_port,
             remote_port,
             auth,
@@ -72,10 +80,8 @@ impl Client {
     pub async fn listen(mut self) -> Result<()> {
         let mut conn = self.conn.take().unwrap();
         let this = Arc::new(self);
-        let mut buf = Vec::new();
         loop {
-            let msg = recv_json(&mut conn, &mut buf).await?;
-            match msg {
+            match conn.recv().await? {
                 Some(ServerMessage::Hello(_)) => warn!("unexpected hello"),
                 Some(ServerMessage::Challenge(_)) => warn!("unexpected challenge"),
                 Some(ServerMessage::Heartbeat) => (),
@@ -99,21 +105,25 @@ impl Client {
     }
 
     async fn handle_connection(&self, id: Uuid) -> Result<()> {
-        let local_conn = TcpStream::connect(("localhost", self.local_port))
-            .await
-            .context("failed TCP connection to local port")?;
-        let mut remote_conn = BufReader::new(
-            TcpStream::connect((&self.to[..], CONTROL_PORT))
-                .await
-                .context("failed TCP connection to remote port")?,
-        );
-
+        let mut remote_conn =
+            Delimited::new(connect_with_timeout(&self.to[..], CONTROL_PORT).await?);
         if let Some(auth) = &self.auth {
             auth.client_handshake(&mut remote_conn).await?;
         }
-
-        send_json(&mut remote_conn, ClientMessage::Accept(id)).await?;
-        proxy(local_conn, remote_conn).await?;
+        remote_conn.send(ClientMessage::Accept(id)).await?;
+        let mut local_conn = connect_with_timeout(&self.local_host, self.local_port).await?;
+        let parts = remote_conn.into_parts();
+        debug_assert!(parts.write_buf.is_empty(), "framed write buffer not empty");
+        local_conn.write_all(&parts.read_buf).await?; // mostly of the cases, this will be empty
+        proxy(local_conn, parts.io).await?;
         Ok(())
     }
 }
+
+async fn connect_with_timeout(to: &str, port: u16) -> Result<TcpStream> {
+    match timeout(NETWORK_TIMEOUT, TcpStream::connect((to, port))).await {
+        Ok(res) => res,
+        Err(err) => Err(err.into()),
+    }
+    .with_context(|| format!("could not connect to {to}:{port}"))
+}

src/main.rs

@@ -1,10 +1,9 @@
 use anyhow::Result;
 use bore_cli::{client::Client, server::Server};
-use clap::{Parser, Subcommand};
+use clap::{error::ErrorKind, CommandFactory, Parser, Subcommand};
 
 #[derive(Parser, Debug)]
 #[clap(author, version, about)]
-#[clap(propagate_version = true)]
 struct Args {
     #[clap(subcommand)]
     command: Command,
@@ -14,11 +13,15 @@ struct Args {
 enum Command {
     /// Starts a local proxy to the remote server.
     Local {
-        /// The local port to listen on.
+        /// The local port to expose.
         local_port: u16,
 
+        /// The local host to expose.
+        #[clap(short, long, value_name = "HOST", default_value = "localhost")]
+        local_host: String,
+
         /// Address of the remote server to expose local ports to.
-        #[clap(short, long)]
+        #[clap(short, long, env = "BORE_SERVER")]
         to: String,
 
         /// Optional port on the remote server to select.
@@ -26,41 +29,58 @@ enum Command {
         port: u16,
 
         /// Optional secret for authentication.
-        #[clap(short, long)]
+        #[clap(short, long, env = "BORE_SECRET", hide_env_values = true)]
         secret: Option<String>,
     },
 
     /// Runs the remote proxy server.
     Server {
-        /// Minimum TCP port number to accept.
+        /// Minimum accepted TCP port number.
         #[clap(long, default_value_t = 1024)]
         min_port: u16,
 
+        /// Maximum accepted TCP port number.
+        #[clap(long, default_value_t = 65535)]
+        max_port: u16,
+
         /// Optional secret for authentication.
-        #[clap(short, long)]
+        #[clap(short, long, env = "BORE_SECRET", hide_env_values = true)]
         secret: Option<String>,
     },
 }
 
 #[tokio::main]
-async fn main() -> Result<()> {
-    tracing_subscriber::fmt::init();
-
-    let args = Args::parse();
-    match args.command {
+async fn run(command: Command) -> Result<()> {
+    match command {
         Command::Local {
+            local_host,
             local_port,
             to,
             port,
             secret,
         } => {
-            let client = Client::new(local_port, &to, port, secret.as_deref()).await?;
+            let client = Client::new(&local_host, local_port, &to, port, secret.as_deref()).await?;
             client.listen().await?;
         }
-        Command::Server { min_port, secret } => {
-            Server::new(min_port, secret.as_deref()).listen().await?;
+        Command::Server {
+            min_port,
+            max_port,
+            secret,
+        } => {
+            let port_range = min_port..=max_port;
+            if port_range.is_empty() {
+                Args::command()
+                    .error(ErrorKind::InvalidValue, "port range is empty")
+                    .exit();
+            }
+            Server::new(port_range, secret.as_deref()).listen().await?;
         }
     }
 
     Ok(())
 }
+
+fn main() -> Result<()> {
+    tracing_subscriber::fmt::init();
+    run(Args::parse().command)
+}

src/server.rs

@@ -1,24 +1,22 @@
 //! Server implementation for the `bore` service.
 
-use std::net::SocketAddr;
-use std::sync::Arc;
-use std::time::Duration;
+use std::{io, net::SocketAddr, ops::RangeInclusive, sync::Arc, time::Duration};
 
 use anyhow::Result;
 use dashmap::DashMap;
-use tokio::io::BufReader;
+use tokio::io::AsyncWriteExt;
 use tokio::net::{TcpListener, TcpStream};
 use tokio::time::{sleep, timeout};
 use tracing::{info, info_span, warn, Instrument};
 use uuid::Uuid;
 
 use crate::auth::Authenticator;
-use crate::shared::{proxy, recv_json, send_json, ClientMessage, ServerMessage, CONTROL_PORT};
+use crate::shared::{proxy, ClientMessage, Delimited, ServerMessage, CONTROL_PORT};
 
 /// State structure for the server.
 pub struct Server {
-    /// The minimum TCP port that can be forwarded.
-    min_port: u16,
+    /// Range of TCP ports that can be forwarded.
+    port_range: RangeInclusive<u16>,
 
     /// Optional secret used to authenticate clients.
     auth: Option<Authenticator>,
@@ -29,9 +27,10 @@ pub struct Server {
 
 impl Server {
     /// Create a new server with a specified minimum port number.
-    pub fn new(min_port: u16, secret: Option<&str>) -> Self {
+    pub fn new(port_range: RangeInclusive<u16>, secret: Option<&str>) -> Self {
+        assert!(!port_range.is_empty(), "must provide at least one port");
         Server {
-            min_port,
+            port_range,
             conns: Arc::new(DashMap::new()),
             auth: secret.map(Authenticator::new),
         }
@@ -61,50 +60,72 @@ impl Server {
         }
     }
 
+    async fn create_listener(&self, port: u16) -> Result<TcpListener, &'static str> {
+        let try_bind = |port: u16| async move {
+            TcpListener::bind(("0.0.0.0", port))
+                .await
+                .map_err(|err| match err.kind() {
+                    io::ErrorKind::AddrInUse => "port already in use",
+                    io::ErrorKind::PermissionDenied => "permission denied",
+                    _ => "failed to bind to port",
+                })
+        };
+        if port > 0 {
+            // Client requests a specific port number.
+            if !self.port_range.contains(&port) {
+                return Err("client port number not in allowed range");
+            }
+            try_bind(port).await
+        } else {
+            // Client requests any available port in range.
+            //
+            // In this case, we bind to 150 random port numbers. We choose this value because in
+            // order to find a free port with probability at least 1-δ, when ε proportion of the
+            // ports are currently available, it suffices to check approximately -2 ln(δ) / ε
+            // independently and uniformly chosen ports (up to a second-order term in ε).
+            //
+            // Checking 150 times gives us 99.999% success at utilizing 85% of ports under these
+            // conditions, when ε=0.15 and δ=0.00001.
+            for _ in 0..150 {
+                let port = fastrand::u16(self.port_range.clone());
+                match try_bind(port).await {
+                    Ok(listener) => return Ok(listener),
+                    Err(_) => continue,
+                }
+            }
+            Err("failed to find an available port")
+        }
+    }
+
     async fn handle_connection(&self, stream: TcpStream) -> Result<()> {
-        let mut stream = BufReader::new(stream);
+        let mut stream = Delimited::new(stream);
         if let Some(auth) = &self.auth {
             if let Err(err) = auth.server_handshake(&mut stream).await {
                 warn!(%err, "server handshake failed");
-                send_json(&mut stream, ServerMessage::Error(err.to_string())).await?;
+                stream.send(ServerMessage::Error(err.to_string())).await?;
                 return Ok(());
             }
         }
 
-        let mut buf = Vec::new();
-        let msg = recv_json(&mut stream, &mut buf).await?;
-
-        match msg {
+        match stream.recv_timeout().await? {
             Some(ClientMessage::Authenticate(_)) => {
                 warn!("unexpected authenticate");
                 Ok(())
             }
             Some(ClientMessage::Hello(port)) => {
-                if port != 0 && port < self.min_port {
-                    warn!(?port, "client port number too low");
-                    return Ok(());
-                }
-                info!(?port, "new client");
-                let listener = match TcpListener::bind(("::", port)).await {
+                let listener = match self.create_listener(port).await {
                     Ok(listener) => listener,
-                    Err(_) => {
-                        warn!(?port, "could not bind to local port");
-                        send_json(
-                            &mut stream,
-                            ServerMessage::Error("port already in use".into()),
-                        )
-                        .await?;
+                    Err(err) => {
+                        stream.send(ServerMessage::Error(err.into())).await?;
                         return Ok(());
                     }
                 };
                 let port = listener.local_addr()?.port();
-                send_json(&mut stream, ServerMessage::Hello(port)).await?;
+                info!(?port, "new client");
+                stream.send(ServerMessage::Hello(port)).await?;
 
                 loop {
-                    if send_json(&mut stream, ServerMessage::Heartbeat)
-                        .await
-                        .is_err()
-                    {
+                    if stream.send(ServerMessage::Heartbeat).await.is_err() {
                         // Assume that the TCP connection has been dropped.
                         return Ok(());
                     }
@@ -124,28 +145,24 @@ impl Server {
                                 warn!(%id, "removed stale connection");
                             }
                         });
-                        send_json(&mut stream, ServerMessage::Connection(id)).await?;
+                        stream.send(ServerMessage::Connection(id)).await?;
                     }
                 }
             }
             Some(ClientMessage::Accept(id)) => {
                 info!(%id, "forwarding connection");
                 match self.conns.remove(&id) {
-                    Some((_, stream2)) => proxy(stream, stream2).await?,
+                    Some((_, mut stream2)) => {
+                        let parts = stream.into_parts();
+                        debug_assert!(parts.write_buf.is_empty(), "framed write buffer not empty");
+                        stream2.write_all(&parts.read_buf).await?;
+                        proxy(parts.io, stream2).await?
+                    }
                     None => warn!(%id, "missing connection"),
                 }
                 Ok(())
             }
-            None => {
-                warn!("unexpected EOF");
-                Ok(())
-            }
+            None => Ok(()),
         }
     }
 }
-
-impl Default for Server {
-    fn default() -> Self {
-        Server::new(1024, None)
-    }
-}

src/shared.rs

@@ -1,14 +1,25 @@
 //! Shared data structures, utilities, and protocol definitions.
 
+use std::time::Duration;
+
 use anyhow::{Context, Result};
-use serde::de::DeserializeOwned;
-use serde::{Deserialize, Serialize};
-use tokio::io::{self, AsyncBufRead, AsyncBufReadExt, AsyncRead, AsyncWrite, AsyncWriteExt};
+use futures_util::{SinkExt, StreamExt};
+use serde::{de::DeserializeOwned, Deserialize, Serialize};
+use tokio::io::{self, AsyncRead, AsyncWrite};
+use tokio::time::timeout;
+use tokio_util::codec::{AnyDelimiterCodec, Framed, FramedParts};
+use tracing::trace;
 use uuid::Uuid;
 
 /// TCP port used for control connections with the server.
 pub const CONTROL_PORT: u16 = 7835;
 
+/// Maxmium byte length for a JSON frame in the stream.
+pub const MAX_FRAME_LENGTH: usize = 256;
+
+/// Timeout for network connections and initial protocol messages.
+pub const NETWORK_TIMEOUT: Duration = Duration::from_secs(3);
+
 /// A message from the client on the control connection.
 #[derive(Debug, Serialize, Deserialize)]
 pub enum ClientMessage {
@@ -41,6 +52,52 @@ pub enum ServerMessage {
     Error(String),
 }
 
+/// Transport stream with JSON frames delimited by null characters.
+pub struct Delimited<U>(Framed<U, AnyDelimiterCodec>);
+
+impl<U: AsyncRead + AsyncWrite + Unpin> Delimited<U> {
+    /// Construct a new delimited stream.
+    pub fn new(stream: U) -> Self {
+        let codec = AnyDelimiterCodec::new_with_max_length(vec![0], vec![0], MAX_FRAME_LENGTH);
+        Self(Framed::new(stream, codec))
+    }
+
+    /// Read the next null-delimited JSON instruction from a stream.
+    pub async fn recv<T: DeserializeOwned>(&mut self) -> Result<Option<T>> {
+        trace!("waiting to receive json message");
+        if let Some(next_message) = self.0.next().await {
+            let byte_message = next_message.context("frame error, invalid byte length")?;
+            let serialized_obj =
+                serde_json::from_slice(&byte_message).context("unable to parse message")?;
+            Ok(serialized_obj)
+        } else {
+            Ok(None)
+        }
+    }
+
+    /// Read the next null-delimited JSON instruction, with a default timeout.
+    ///
+    /// This is useful for parsing the initial message of a stream for handshake or
+    /// other protocol purposes, where we do not want to wait indefinitely.
+    pub async fn recv_timeout<T: DeserializeOwned>(&mut self) -> Result<Option<T>> {
+        timeout(NETWORK_TIMEOUT, self.recv())
+            .await
+            .context("timed out waiting for initial message")?
+    }
+
+    /// Send a null-terminated JSON instruction on a stream.
+    pub async fn send<T: Serialize>(&mut self, msg: T) -> Result<()> {
+        trace!("sending json message");
+        self.0.send(serde_json::to_string(&msg)?).await?;
+        Ok(())
+    }
+
+    /// Consume this object, returning current buffers and the inner transport.
+    pub fn into_parts(self) -> FramedParts<U, AnyDelimiterCodec> {
+        self.0.into_parts()
+    }
+}
+
 /// Copy data mutually between two read/write streams.
 pub async fn proxy<S1, S2>(stream1: S1, stream2: S2) -> io::Result<()>
 where
@@ -49,33 +106,9 @@ where
 {
     let (mut s1_read, mut s1_write) = io::split(stream1);
     let (mut s2_read, mut s2_write) = io::split(stream2);
-    tokio::try_join!(
-        io::copy(&mut s1_read, &mut s2_write),
-        io::copy(&mut s2_read, &mut s1_write),
-    )?;
-    Ok(())
-}
-
-/// Read the next null-delimited JSON instruction from a stream.
-pub async fn recv_json<T: DeserializeOwned>(
-    reader: &mut (impl AsyncBufRead + Unpin),
-    buf: &mut Vec<u8>,
-) -> Result<Option<T>> {
-    buf.clear();
-    reader.read_until(0, buf).await?;
-    if buf.is_empty() {
-        return Ok(None);
-    }
-    if buf.last() == Some(&0) {
-        buf.pop();
-    }
-    Ok(serde_json::from_slice(buf).context("failed to parse JSON")?)
-}
-
-/// Send a null-terminated JSON instruction on a stream.
-pub async fn send_json<T: Serialize>(writer: &mut (impl AsyncWrite + Unpin), msg: T) -> Result<()> {
-    let msg = serde_json::to_vec(&msg)?;
-    writer.write_all(&msg).await?;
-    writer.write_all(&[0]).await?;
+    tokio::select! {
+        res = io::copy(&mut s1_read, &mut s2_write) => res,
+        res = io::copy(&mut s2_read, &mut s1_write) => res,
+    }?;
     Ok(())
 }

tests/auth_test.rs

@@ -0,0 +1,35 @@
+use anyhow::Result;
+use bore_cli::{auth::Authenticator, shared::Delimited};
+use tokio::io::{self};
+
+#[tokio::test]
+async fn auth_handshake() -> Result<()> {
+    let auth = Authenticator::new("some secret string");
+
+    let (client, server) = io::duplex(8); // Ensure correctness with limited capacity.
+    let mut client = Delimited::new(client);
+    let mut server = Delimited::new(server);
+
+    tokio::try_join!(
+        auth.client_handshake(&mut client),
+        auth.server_handshake(&mut server),
+    )?;
+
+    Ok(())
+}
+
+#[tokio::test]
+async fn auth_handshake_fail() {
+    let auth = Authenticator::new("client secret");
+    let auth2 = Authenticator::new("different server secret");
+
+    let (client, server) = io::duplex(8); // Ensure correctness with limited capacity.
+    let mut client = Delimited::new(client);
+    let mut server = Delimited::new(server);
+
+    let result = tokio::try_join!(
+        auth.client_handshake(&mut client),
+        auth2.server_handshake(&mut server),
+    );
+    assert!(result.is_err());
+}

tests/e2e_test.rs

@@ -0,0 +1,127 @@
+use std::net::SocketAddr;
+use std::time::Duration;
+
+use anyhow::{anyhow, Result};
+use bore_cli::{client::Client, server::Server, shared::CONTROL_PORT};
+use lazy_static::lazy_static;
+use rstest::*;
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use tokio::net::{TcpListener, TcpStream};
+use tokio::sync::Mutex;
+use tokio::time;
+
+lazy_static! {
+    /// Guard to make sure that tests are run serially, not concurrently.
+    static ref SERIAL_GUARD: Mutex<()> = Mutex::new(());
+}
+
+/// Spawn the server, giving some time for the control port TcpListener to start.
+async fn spawn_server(secret: Option<&str>) {
+    tokio::spawn(Server::new(1024..=65535, secret).listen());
+    time::sleep(Duration::from_millis(50)).await;
+}
+
+/// Spawns a client with randomly assigned ports, returning the listener and remote address.
+async fn spawn_client(secret: Option<&str>) -> Result<(TcpListener, SocketAddr)> {
+    let listener = TcpListener::bind("localhost:0").await?;
+    let local_port = listener.local_addr()?.port();
+    let client = Client::new("localhost", local_port, "localhost", 0, secret).await?;
+    let remote_addr = ([127, 0, 0, 1], client.remote_port()).into();
+    tokio::spawn(client.listen());
+    Ok((listener, remote_addr))
+}
+
+#[rstest]
+#[tokio::test]
+async fn basic_proxy(#[values(None, Some(""), Some("abc"))] secret: Option<&str>) -> Result<()> {
+    let _guard = SERIAL_GUARD.lock().await;
+
+    spawn_server(secret).await;
+    let (listener, addr) = spawn_client(secret).await?;
+
+    tokio::spawn(async move {
+        let (mut stream, _) = listener.accept().await?;
+        let mut buf = [0u8; 11];
+        stream.read_exact(&mut buf).await?;
+        assert_eq!(&buf, b"hello world");
+
+        stream.write_all(b"I can send a message too!").await?;
+        anyhow::Ok(())
+    });
+
+    let mut stream = TcpStream::connect(addr).await?;
+    stream.write_all(b"hello world").await?;
+
+    let mut buf = [0u8; 25];
+    stream.read_exact(&mut buf).await?;
+    assert_eq!(&buf, b"I can send a message too!");
+
+    // Ensure that the client end of the stream is closed now.
+    assert_eq!(stream.read(&mut buf).await?, 0);
+
+    // Also ensure that additional connections do not produce any data.
+    let mut stream = TcpStream::connect(addr).await?;
+    assert_eq!(stream.read(&mut buf).await?, 0);
+
+    Ok(())
+}
+
+#[rstest]
+#[case(None, Some("my secret"))]
+#[case(Some("my secret"), None)]
+#[tokio::test]
+async fn mismatched_secret(
+    #[case] server_secret: Option<&str>,
+    #[case] client_secret: Option<&str>,
+) {
+    let _guard = SERIAL_GUARD.lock().await;
+
+    spawn_server(server_secret).await;
+    assert!(spawn_client(client_secret).await.is_err());
+}
+
+#[tokio::test]
+async fn invalid_address() -> Result<()> {
+    // We don't need the serial guard for this test because it doesn't create a server.
+    async fn check_address(to: &str, use_secret: bool) -> Result<()> {
+        match Client::new("localhost", 5000, to, 0, use_secret.then_some("a secret")).await {
+            Ok(_) => Err(anyhow!("expected error for {to}, use_secret={use_secret}")),
+            Err(_) => Ok(()),
+        }
+    }
+    tokio::try_join!(
+        check_address("google.com", false),
+        check_address("google.com", true),
+        check_address("nonexistent.domain.for.demonstration", false),
+        check_address("nonexistent.domain.for.demonstration", true),
+        check_address("malformed !$uri$%", false),
+        check_address("malformed !$uri$%", true),
+    )?;
+    Ok(())
+}
+
+#[tokio::test]
+async fn very_long_frame() -> Result<()> {
+    let _guard = SERIAL_GUARD.lock().await;
+
+    spawn_server(None).await;
+    let mut attacker = TcpStream::connect(("localhost", CONTROL_PORT)).await?;
+
+    // Slowly send a very long frame.
+    for _ in 0..10 {
+        let result = attacker.write_all(&[42u8; 100000]).await;
+        if result.is_err() {
+            return Ok(());
+        }
+        time::sleep(Duration::from_millis(10)).await;
+    }
+    panic!("did not exit after a 1 MB frame");
+}
+
+#[test]
+#[should_panic]
+fn empty_port_range() {
+    let min_port = 5000;
+    let max_port = 3000;
+    let _ = Server::new(min_port..=max_port, None);
+}