Add module to configure sshd

nixos/ssh.nix

@@ -0,0 +1,27 @@
+{lib, ...}: {
+  options = {
+    pim.ssh.keys = lib.mkOption {
+      type = lib.types.attrsOf (lib.types.listOf lib.types.str);
+    };
+  };
+
+  config = {
+    pim.ssh.keys = {
+      pim = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOodpLr+FDRyKyHjucHizNLVFHZ5AQmE9GmxMnOsSoaw pimkunis@thinkpadpim"];
+      niels = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAINUZp4BCxf7uLa1QWonx/Crf8tYZ5MKIZ+EuaBa82LrV user@user-laptop"];
+    };
+
+    services = {
+      openssh = {
+        openFirewall = true;
+
+        settings = {
+          PasswordAuthentication = false;
+          KbdInteractiveAuthentication = false;
+          GSSAPIAuthentication = false;
+          UseDns = false;
+        };
+      };
+    };
+  };
+}