Write relay message to the network

src/main.zig

@@ -189,6 +189,10 @@ pub fn main(init: std.process.Init) !void {
     };
 
     std.debug.print("full message = {any}\n", .{full_msg});
+
+    var socket: RawSocket = try .init("enp7s0");
+    defer socket.deinit();
+    try socket.send(full_msg);
 }
 
 fn parseDest(in: ?[]const u8) [4]u8 {
@@ -222,7 +226,7 @@ const RawSocket = struct {
     fd: i32,
     sockaddr_ll: std.posix.sockaddr.ll,
 
-    fn init(ifname: []const u8) RawSocket {
+    fn init(ifname: []const u8) !RawSocket {
         const socket: i32 = @intCast(std.os.linux.socket(AF.PACKET, SOCK.RAW, 0));
 
         var ifr: std.posix.ifreq = std.mem.zeroInit(std.posix.ifreq, .{});
@@ -265,7 +269,9 @@ const RawSocket = struct {
         };
     }
 
-    fn deinit() void {}
+    fn deinit(self: *RawSocket) void {
+        _ = self;
+    }
 
     fn send(self: RawSocket, payload: []const u8) !void {
         const sent_bytes = std.os.linux.sendto(

src/message.zig

@@ -123,7 +123,7 @@ const Relay = struct {
     pub fn toBytes(self: Relay, buf: []u8) []u8 {
         var out: Writer = .fixed(buf);
         out.writeInt(u16, @intFromEnum(PacketType.relay), .big) catch unreachable;
-        out.writeInt(u16, undefined, .big) catch unreachable; // Length field, but unread. Will switch to checksum
+        out.writeInt(u16, @intCast(self.payload.len), .big) catch unreachable; // Length field, but unread. Will switch to checksum
         out.writeAll(&self.dest.bytes) catch unreachable;
         out.writeAll(self.payload) catch unreachable;
         return out.buffered();