fix(workspace_trust): secure permissions on Unix

Author: Rudxain

helix-loader/src/workspace_trust.rs

@@ -1,3 +1,4 @@
+use helix_stdx::faccess::write_with_perms;
 use std::{collections::HashSet, fs, path::PathBuf};
 
 use crate::{data_dir, workspace_exclude_file, workspace_trust_file};
@@ -71,8 +72,7 @@ impl WorkspaceTrust {
                 log::error!("Couldn't create helix's data directory: {:?}", e);
             };
         }
-        // TO-DO: ensure only owner has write permission
-        if let Err(e) = fs::write(workspace_trust_file(), trust_text) {
+        if let Err(e) = write_with_perms(workspace_trust_file(), trust_text, 0o0644) {
             log::error!("Error during write of workspace_trust file: {:?}", e);
         }
     }
@@ -93,8 +93,7 @@ impl WorkspaceTrust {
                     log::error!("Couldn't create helix's data directory: {:?}", e);
                 };
             }
-            // TO-DO: ensure only owner has write permission
-            if let Err(e) = fs::write(workspace_exclude_file(), trust_text) {
+            if let Err(e) = write_with_perms(workspace_exclude_file(), trust_text, 0o0644) {
                 log::error!("Error during write of workspace_trust file: {:?}", e);
             }
         } else {

helix-stdx/src/faccess.rs

@@ -1,4 +1,4 @@
-//! Functions for managine file metadata.
+//! Functions for managing file metadata.
 //! From <https://github.com/Freaky/faccess>
 
 use std::io;
@@ -95,6 +95,24 @@ mod imp {
         Ok(())
     }
 
+    /// Same as [`fs::write`][std::fs::write], but sets mode bits on Unix targets
+    pub fn write_with_perms<P: AsRef<Path>, C: AsRef<[u8]>>(
+        path: P,
+        contents: C,
+        perms: u16,
+    ) -> io::Result<()> {
+        fn inner(path: &Path, contents: &[u8], perms: u16) -> io::Result<()> {
+            let f = std::fs::File::create(path)?;
+            #[cfg(target_family = "unix")]
+            {
+                let p = f.metadata()?.permissions().set_mode(perms);
+                std::fs::set_permissions(f, p)?
+            }
+            f.write_all(contents)
+        }
+        inner(path.as_ref(), contents.as_ref(), perms)
+    }
+
     pub fn hardlink_count(p: &Path) -> std::io::Result<u64> {
         let metadata = p.metadata()?;
         Ok(metadata.nlink())