Nick Mathewson · Nick Mathewson · a60cf1b0 · a60cf1b0 · a60cf1b0 · a60cf1b0
--- a/crates/fs-mistrust/src/disable.rs 0 → 100644
+++ b/crates/fs-mistrust/src/disable.rs 0 → 100644
+/// assuming that if you set a disable variable, you meant to disable.)
+///
+/// Absent environment vars are treated as None.
+#[allow(clippy::match_like_matches_macro)]
+fn from_env_var_value(input: std::result::Result<String, VarError>) -> Option<bool> {
+    let mut s = match input {
+        Ok(s) => s,
+        Err(VarError::NotPresent) => return None,
+        Err(VarError::NotUnicode(_)) => return Some(true),
+    };
+
+    s.make_ascii_lowercase();
+    Some(match s.as_ref() {
+        "0" | "no" | "never" | "false" | "" => false,
+        _ => true,
+    })
--- a/crates/fs-mistrust/src/disable.rs 0 → 100644
+++ b/crates/fs-mistrust/src/disable.rs 0 → 100644
+        Ok(s) => s,
+        Err(VarError::NotPresent) => return None,
+        Err(VarError::NotUnicode(_)) => return Some(true),
+    };
+
+    s.make_ascii_lowercase();
+    Some(match s.as_ref() {
+        "0" | "no" | "never" | "false" | "" => false,
+        _ => true,
+    })
+}
+
+impl Disable {
+    /// Return true if, based on this [`Disable`] setting, and on the
+    /// environment, we should disable permissions checking.
+    pub(crate) fn should_disable_checks(&self) -> bool {
--- a/crates/fs-mistrust/src/disable.rs 0 → 100644
+++ b/crates/fs-mistrust/src/disable.rs 0 → 100644
+                .unwrap_or(false),
+            Disable::OnGlobalEnvVar => {
+                from_env_var_value(env::var(GLOBAL_DISABLE_VAR)).unwrap_or(false)
+            }
+            Disable::Never => false,
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    #[test]
+    fn from_val() {
+        assert_eq!(from_env_var_value(Ok("yes".into())), Some(true));
+        assert_eq!(from_env_var_value(Ok("no".into())), Some(false));
-        assert_eq!(from_env_var_value(Ok("yes".into())), Some(true));
-        assert_eq!(from_env_var_value(Ok("no".into())), Some(false));
+        assert_eq!(from_env_var_value(Ok("yes".into())), Some(true));
+        assert_eq!(from_env_var_value(Ok("y".into())), Some(true));
+        assert_eq!(from_env_var_value(Ok("1".into())), Some(true));
+        assert_eq!(from_env_var_value(Ok("no".into())), Some(false));
+        assert_eq!(from_env_var_value(Ok("n".into())), Some(false));
+        assert_eq!(from_env_var_value(Ok("0".into())), Some(false));
--- a/crates/arti/src/lib.rs
+++ b/crates/arti/src/lib.rs
        let matches = clap_app.get_matches();

-        let fs_mistrust_disabled = fs_permissions_checks_disabled_via_env()
-            | matches.is_present("disable-fs-permission-checks");
+        let fs_mistrust_disabled = matches.is_present("disable-fs-permission-checks");

        // A Mistrust object to use for loading our configuration.  Elsewhere, we
        // use the value _from_ the configuration.
        let cfg_mistrust = if fs_mistrust_disabled {
            fs_mistrust::Mistrust::new_dangerously_trust_everyone()
        } else {
-            fs_mistrust::Mistrust::new()
+            fs_mistrust::MistrustBuilder::default()
+                .controlled_by_env_var(arti_client::config::FS_PERMISSIONS_CHECKS_DISABLE_VAR)
+                .build()
+                .expect("Could not construct default fs-mistrust")