1 files changed, 101 insertions, 0 deletions

diff --git a/src/persist.rs b/src/persist.rs
new file mode 100644
index 0000000..7d47232
--- /dev/null
+++ b/src/persist.rs
@@ -0,0 +1,101 @@
+use std::fs;
+use std::os::linux::fs::MetadataExt;
+use std::os::unix::prelude::PermissionsExt;
+use std::time::SystemTime;
+use nix::unistd;
+use serde_json::Value;
+
+const PERSIST_TIME:         u64 = 60 * 3;
+
+pub fn get_persist(user: &str) -> bool {
+  let json = match get_terminal_config() {
+      Some(data) => data,
+      None => return false
+  };
+  let timestamp = match json[user].as_u64() {
+      Some(data) => data,
+      None => return false
+  };
+  return now() - timestamp < PERSIST_TIME;
+}
+
+pub fn set_persist(user: &str) {
+  let mut json = match get_terminal_config() {
+      Some(data) => data,
+      None => return
+  };
+  json[user] = Value::from(now());
+  let id = match get_terminal_process() {
+      Some(data) => data,
+      None => return
+  };
+  match write_terminal_config(&id, &json.to_string()) {
+      Ok(_) => {},
+      Err(e) => {
+          eprintln!("Internal Error: {}", e)
+      }
+  };
+}
+
+fn get_terminal_process() -> Option<i32> {
+  let id: i32 = match std::process::id().try_into() {
+      Ok(data) => data,
+      Err(_) => return None
+  };
+  let stat = match procinfo::pid::stat(id) {
+      Ok(data) => data,
+      Err(_) => return None
+  };
+  Some(stat.session)
+}
+
+fn is_file_root_only(id: &i32) -> bool {
+  let metadata = match std::fs::metadata(path(&id)) {
+      Ok(data) => data,
+      Err(e) => {
+          if let Some(err) = e.raw_os_error() {
+              return err == 2;
+          }
+          return true
+      }
+  };
+  let perms = metadata.permissions();
+  return perms.mode() == 33200 && metadata.st_uid() == 0 && metadata.st_gid() == 0;
+}
+
+fn get_terminal_config() -> Option<Value> {
+  let id = match get_terminal_process() {
+      Some(data) => data,
+      None => return None
+  };
+  if !is_file_root_only(&id) {
+      return None;
+  }
+  let data = match std::fs::read_to_string(path(&id)) {
+      Ok(data) => data,
+      Err(_) => "{}".to_string()
+  };
+  let json: Value = match serde_json::from_str(&data) {
+      Ok(data) => data,
+      Err(_) => return None
+  };
+  Some(json)
+}
+
+fn write_terminal_config(id: &i32, data: &str) -> Result<(), Box<dyn std::error::Error>> {
+  std::fs::write(path(&id), data)?;
+  unistd::chown(std::path::Path::new(&path(&id)), Some(unistd::Uid::from(0)), Some(unistd::Gid::from(0)))?;
+  let metadata = std::fs::metadata(path(&id))?;
+  let mut perms = metadata.permissions();
+  perms.set_mode(0o660);
+  fs::set_permissions(path(&id), perms)?;
+  Ok(())
+}
+
+fn now() -> u64 {
+  return SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
+}
+
+fn path(id: &i32) -> String {
+  return format!("/tmp/crab-{}", id);
+}
\ No newline at end of file