echo-server.yml

name: echo-server

on:
  push:
    branches: [ 'main' ]
  pull_request:
    branches: [ '*' ]

jobs:
  build-and-test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          submodules: recursive

      - name: Install dependencies
        run: sudo apt-get update && sudo apt-get install -y libpcap-dev iproute2 ethtool tcpdump sshpass

      - name: Setup network and detect pcap index
        id: pcap
        run: |
          # Clean up any stale veth pair
          sudo ip link del veth0 2>/dev/null || true

          # Create the veth pair
          sudo ip link add veth0 type veth peer name veth1
          sudo ip link set veth0 up
          sudo ip link set veth1 up
          sudo ip addr add 10.0.0.1/24 dev veth0
          sudo ethtool -K veth0 tx off

          # Find veth1's pcap index (1-based, as reported by tcpdump)
          INDEX=$(tcpdump --list-interfaces 2>/dev/null | grep -m1 'veth1' | cut -d. -f1)
          echo "veth1 is pcap interface $INDEX"
          echo "index=$INDEX" >> "$GITHUB_OUTPUT"

      - name: Build
        working-directory: echo-server
        run: make EXTRA_CPPFLAGS=-DipconfigNETWORK_INTERFACE_TO_USE=${{ steps.pcap.outputs.index }}

      - name: Build debug
        working-directory: echo-server
        run: make clean && make BUILD=debug EXTRA_CPPFLAGS=-DipconfigNETWORK_INTERFACE_TO_USE=${{ steps.pcap.outputs.index }}

      - name: Functional test
        working-directory: echo-server
        run: |
          set +e

          # Start the server in the background with a 60s timeout
          sudo timeout 60s ./echo-server > /tmp/echo-server.log 2>&1 &
          SERVER_PID=$!

          # Wait for the server to be ready
          READY=0
          for i in $(seq 1 30); do
            if grep -q "Listening on port 22222" /tmp/echo-server.log 2>/dev/null; then
              echo "Server is listening"
              READY=1
              break
            fi
            sleep 1
          done
          if [ "$READY" -ne 1 ]; then
            echo "FAIL: server did not start in time"
            cat /tmp/echo-server.log
            sudo kill $SERVER_PID 2>/dev/null || true
            sudo ip link del veth0 2>/dev/null || true
            exit 1
          fi

          # Connect and authenticate via SSH. The wolfSSH echo server
          # does not provide a shell, so the client will disconnect after
          # the channel opens.  We just need to verify the SSH handshake
          # and authentication succeed.
          sshpass -p upthehill ssh -T -p 22222 \
            -o StrictHostKeyChecking=no \
            -o UserKnownHostsFile=/dev/null \
            -o ConnectTimeout=10 \
            jill@10.0.0.2 < /dev/null 2>/dev/null
          # ssh exit code is not reliable here since the server
          # closes the channel — check the server log instead
          sleep 1

          # Cleanup
          sudo kill $SERVER_PID 2>/dev/null || true
          sudo ip link del veth0 2>/dev/null || true

          # Verify the server accepted the SSH connection
          if grep -q "SSH connection accepted" /tmp/echo-server.log; then
            echo "PASS: server started, client authenticated, SSH session established"
          else
            echo "FAIL: SSH connection was not accepted"
            cat /tmp/echo-server.log
            exit 1
          fi