From 92ec9fc448740192f4d22b3f3e6f6e320ef2dd10 Mon Sep 17 00:00:00 2001
From: Daniel Mueller <deso@posteo.net>
Date: Sat, 19 Sep 2020 22:31:20 -0700
Subject: [PATCH] Kill scdaemon before each OTP get

TODO: Should probably be done on other paths as well.
---
 extensions/otp-cache/src/main.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/extensions/otp-cache/src/main.rs b/extensions/otp-cache/src/main.rs
index 39505ea7..98e74b1c 100644
--- a/extensions/otp-cache/src/main.rs
+++ b/extensions/otp-cache/src/main.rs
@@ -9,6 +9,7 @@ use std::collections;
 use std::fs;
 use std::io::Write as _;
 use std::path;
+use std::process;
 
 use anyhow::Context as _;
 
@@ -153,6 +154,16 @@ fn load_cache(path: &path::Path) -> anyhow::Result<Cache> {
 }
 
 fn generate_otp(ctx: &ext::Context, args: &Args, slot: u8) -> anyhow::Result<String> {
+  // Attempt to prevent a "hang" of the Nitrokey by killing any scdaemon
+  // that could currently have the device opened itself
+  // (https://github.com/Nitrokey/libnitrokey/issues/137).
+  let _ = process::Command::new("gpg-connect-agent")
+    .stdout(process::Stdio::null())
+    .stderr(process::Stdio::null())
+    .arg("SCD KILLSCD")
+    .arg("/bye")
+    .output();
+
   ext::Nitrocli::from_context(ctx)
     .args(&["otp", "get"])
     .arg(slot.to_string())