From da8866a01a71c1297f817d20e2dc5b26b4df67bf Mon Sep 17 00:00:00 2001
From: Daniel Barlow <dan@telent.net>
Date: Sat, 1 Oct 2022 18:53:20 +0100
Subject: [PATCH] first pass at a hostapd service, rough around the edges

---
 pkgs/liminix-tools/networking/default.nix |  1 +
 pkgs/liminix-tools/networking/hostapd.nix | 39 ++++++++++++++++++++
 tests/wlan/configuration.nix              | 43 +++++++++++++++++++++++
 tests/wlan/run.sh                         | 25 +++++++++++++
 tests/wlan/wait-for-wlan.expect           | 21 +++++++++++
 5 files changed, 129 insertions(+)
 create mode 100644 pkgs/liminix-tools/networking/hostapd.nix
 create mode 100644 tests/wlan/configuration.nix
 create mode 100755 tests/wlan/run.sh
 create mode 100644 tests/wlan/wait-for-wlan.expect

diff --git a/pkgs/liminix-tools/networking/default.nix b/pkgs/liminix-tools/networking/default.nix
index 57694d7..c1818fe 100644
--- a/pkgs/liminix-tools/networking/default.nix
+++ b/pkgs/liminix-tools/networking/default.nix
@@ -28,6 +28,7 @@ in {
   };
   pppoe = callPackage ./pppoe.nix {};
   dnsmasq = callPackage ./dnsmasq.nix {};
+  hostapd = callPackage ./hostapd.nix {};
   route = { name, target, via, dependencies }:
     oneshot {
       inherit name;
diff --git a/pkgs/liminix-tools/networking/hostapd.nix b/pkgs/liminix-tools/networking/hostapd.nix
new file mode 100644
index 0000000..62a3942
--- /dev/null
+++ b/pkgs/liminix-tools/networking/hostapd.nix
@@ -0,0 +1,39 @@
+# This is not a friendly interface to configuring a wireless AP: it
+# just passes everything straight through to the hostapd config.  When
+# we've worked out what the sensible options are to expose, we'll add
+# them as top-level attributes and rename params to extraParams
+
+{
+  liminix
+, hostapd
+, lib
+, writeText
+}:
+interface:
+{
+  params ? {}
+}:
+let
+  inherit (liminix.services) longrun;
+  inherit (lib) concatStringsSep mapAttrsToList;
+  inherit (builtins) toString;
+
+  name = "${interface.device}.hostapd";
+  defaults =  {
+    driver = "nl80211";
+    logger_syslog = "-1";
+    logger_syslog_level = 1;
+    ctrl_interface = "/run/hostapd";
+    ctrl_interface_group = 0;
+  };
+
+  conf = writeText "hostapd.conf"
+    (concatStringsSep
+      "\n"
+      (mapAttrsToList
+        (name: value: "${name}=${toString value}")
+        (defaults // params)));
+in longrun {
+  inherit name;
+  run = "${hostapd}/bin/hostapd -d -i ${interface.device}  -P /run/hostapd.pid -S ${conf}";
+}
diff --git a/tests/wlan/configuration.nix b/tests/wlan/configuration.nix
new file mode 100644
index 0000000..809725d
--- /dev/null
+++ b/tests/wlan/configuration.nix
@@ -0,0 +1,43 @@
+{ config, pkgs, lib, ... } :
+let
+  inherit (pkgs.liminix.networking) interface address hostapd route dnsmasq;
+  inherit (pkgs.liminix.services) oneshot longrun bundle target output;
+in rec {
+  services.loopback =
+    let iface = interface { type = "loopback"; device = "lo";};
+    in bundle {
+      name = "loopback";
+      contents = [
+        (address iface { family = "inet4"; address ="127.0.0.1"; prefixLength = 8;})
+        (address iface { family = "inet6"; address ="::1"; prefixLength = 128;})
+      ];
+    };
+
+  services.wlan = interface { type = "hardware"; device = "wlan0"; };
+
+  services.hostap = hostapd (services.wlan) {
+    params = {
+      ssid = "liminix";
+      country_code = "GB";
+      hw_mode="g";
+      channel = "2";
+      wmm_enabled = 1;
+      ieee80211n = 1;
+      wpa_passphrase = "colourless green ideas";
+      auth_algs = 1; # 1=wpa2, 2=wep, 3=both
+      wpa = 2;       # 1=wpa, 2=wpa2, 3=both
+      wpa_key_mgmt = "WPA-PSK";
+      wpa_pairwise = "TKIP CCMP";   # auth for wpa (may not need this?)
+      rsn_pairwise = "CCMP";        # auth for wpa2
+    };
+  };
+
+  services.default = target {
+    name = "default";
+    contents = with services; [
+      loopback
+      hostap
+    ];
+  };
+  defaultProfile.packages = with pkgs;  [ tcpdump ] ;
+}
diff --git a/tests/wlan/run.sh b/tests/wlan/run.sh
new file mode 100755
index 0000000..0c538e8
--- /dev/null
+++ b/tests/wlan/run.sh
@@ -0,0 +1,25 @@
+#!/usr/bin/env sh
+
+cleanup(){
+    if test -e foo.pid && test -d /proc/`cat foo.pid` ; then
+	echo "killing qemu"
+	kill `cat foo.pid`
+    fi
+}
+trap cleanup EXIT
+fatal(){
+    err=$?
+    echo "FAIL: command $(eval echo $BASH_COMMAND) exited with code $err"
+    exit $err
+}
+trap fatal ERR
+
+NIXPKGS_ALLOW_UNSUPPORTED_SYSTEM=1 nix-build '<liminix>' -I liminix-config=./configuration.nix --arg device "import <liminix/devices/qemu.nix>" -A outputs.default $*
+
+
+
+../../scripts/run-qemu.sh \
+    --background foo.sock \
+    result/vmlinux result/squashfs \
+
+nix-shell -p expect --run "expect wait-for-wlan.expect"
diff --git a/tests/wlan/wait-for-wlan.expect b/tests/wlan/wait-for-wlan.expect
new file mode 100644
index 0000000..4e2f8a0
--- /dev/null
+++ b/tests/wlan/wait-for-wlan.expect
@@ -0,0 +1,21 @@
+set timeout 60
+
+spawn socat unix-connect:foo.sock -
+send "\r\n"
+expect "login:" {  send "root\r\n" }
+expect "/ #"
+set FINISHED 0
+set EXIT "1"
+send "ls -l /run/uncaught-logs/current\r\n"
+expect "/ #"
+while { $FINISHED < 10 } {
+  send "grep AP-ENABLED /run/uncaught-logs/current || echo not\r\n"
+  
+  expect {
+    "wlan0: AP-ENABLED" { set FINISHED 10; set EXIT 0; }
+    "not" { send_user "waiting ..." ; sleep 5 }
+  }
+  set FINISHED [ expr $FINISHED + 1 ]
+}
+
+exit $EXIT