experimental netlink code

blinkenlicht/netlink.nix

@@ -0,0 +1,53 @@
+{ lua, lib,  fetchFromGitHub, buildLuaPackage, libmnl }:
+let pname = "netlink";
+in buildLuaPackage {
+  inherit pname;
+  version = "0.1.1-1";
+
+  buildInputs = [ libmnl ];
+
+  src = fetchFromGitHub {
+    repo = "lua-netlink";
+    owner = "chris2511";
+    rev = "v0.1.1";
+    hash = "sha256:1833naskl4p7rz5kk0byfgngvw1mvf6cnz64sr3ny7i202wv7s52";
+  };
+  buildPhase = "$CC -shared -l mnl -o netlink.so src/*.c";
+
+  installPhase = ''
+    mkdir -p "$out/lib/lua/${lua.luaversion}"
+    cp  netlink.so "$out/lib/lua/${lua.luaversion}/"
+  '';
+
+}
+
+
+# , fetchFromGitHub }:
+# let
+
+#   simpleName = "netlink";
+
+# in
+# # TODO: add busted and checkPhase?
+# buildLuaPackage rec {
+#   version = "0.10.2";
+#   pname = simpleName; # nixpkgs unstable needs this
+#   name = "${pname}-${version}"; # nixpkgs 21.11 needs this
+
+#   src = fetchFromGitHub {
+#     owner = "stefano-m";
+#     repo = "lua-${simpleName}";
+#     rev = "v${version}";
+#     sha256 = "0kl8ff1g1kpmslzzf53cbzfl1bmb5cb91w431hbz0z0vdrramh6l";
+#   };
+
+#   propagatedBuildInputs = [ lgi ];
+
+#   buildPhase = ":";
+
+#   installPhase = ''
+#     mkdir -p "$out/share/lua/${lua.luaversion}"
+#     cp -r src/${pname} "$out/share/lua/${lua.luaversion}/"
+#   '';
+
+# }

blinkenlicht/nl.fnl

@@ -0,0 +1,94 @@
+(local nl (require :netlink))
+(local view (. (require :fennel) :view))
+(print (string.format "All known netlink groups: %s"
+                      (table.concat (nl.groups) ", ")))
+(local nls (nl.socket))
+(print "File descriptor:" (nls:fd))
+
+;; (local links
+;;        (collect
+;;            [_ l (ipairs  (nls:query {:link true}))]
+;;          l.name l))
+;; (print (view links))
+
+;; ;; (local routes (nls:query {:route true}))
+;; ;; (print "Query route status:" (view routes))
+
+;; (print :routes (view (nls:query {:route true})))
+;; (print :route6 (view (nls:query {:route6 true})))
+
+;; ;; (each [_ entry (pairs routes)]
+;; ;;   (local eth (nl.ethtool entry.name))
+;; ;;   (when eth.speed
+;; ;;     (print "ETH:" entry.name (view eth))))
+;; (print "GROUPS:" (view (nls:groups)))
+
+;; when we have a default route, we get the ifname
+
+;; $ grep DEVTYPE /sys/class/net/*/uevent
+;; /sys/class/net/docker0/uevent:DEVTYPE=bridge
+;; /sys/class/net/wlp4s0/uevent:DEVTYPE=wlan
+;; /sys/class/net/wwp0s20f0u2i12/uevent:DEVTYPE=wwan
+;; (ethernet and loopback devices don't have DEVTYPE)
+
+;; if the type is wlan, we can get a signal strength indicator
+;; from the  "quality - link" column of /proc/net/wireless
+;; and network name from `iwgetid wlan0 --raw`
+;; or directly using an ioctl http://papermint-designs.com/dmo-blog/2016-08-how-to-get-the-essid-of-the-wifi-network-you-are-connected-to-#
+
+;; for wwan, need to determine how to get strength and carrier name
+
+(fn find [predicate tbl]
+  (accumulate [found nil
+               _ el (ipairs tbl)]
+              (if (predicate el) el found)))
+
+(print (find #(= $1 "hey") [:one :two :hey :three]))
+
+(fn netlunk []
+  (let [links {}
+        routes {}]
+    (fn handle-event [event]
+;      (print :event (view event))
+      (match event
+        {:event :newlink}
+        (match event.up
+          "yes" (tset links event.index event)
+          "no" (tset links event.index nil))
+
+        {:event :newroute}
+        (tset routes (or event.dst "default")
+              (if (. links event.index)
+                  event
+                  nil))
+
+        {} (print :unhandled event.event)
+        ))
+    (each [_ event (ipairs (nls:query ))]
+      (handle-event event))
+
+    {
+     :refresh #(each [_ event (ipairs (nls:event))]
+                 (handle-event event))
+     :fd (nls:fd)
+     :uplink (fn [self] routes.default)
+     :wait #(nls:poll 1000)
+     :interface (fn [self ifnum] (print :lookup ifnum (view links)) (. links ifnum))
+     }
+    ))
+
+(let [nl (netlunk)]
+  (while (or (nl:wait) true)
+    (nl:refresh)
+    (match (nl:uplink)
+      {:index ifnum}
+      (print "default route through " (. (nl:interface ifnum) :name))
+      {}
+      (print "no default route")
+      )))
+
+
+
+;; default route is newroute event without dst
+
+;; look for newlink event with  :running "yes"