feat: add file loader helpers

src/tls.rs

@@ -1,3 +1,5 @@
+use std::{fs, io};
+use rustls::pki_types::{CertificateDer, PrivateKeyDer};
 use crate::Error;
 use tokio::io::{AsyncRead, AsyncWrite};
 use tokio_rustls::TlsAcceptor;
@@ -51,3 +53,23 @@ where
         }
     })
 }
+
+// Load the public certificate from a file.
+fn load_certs(filename: &str) -> io::Result<Vec<CertificateDer<'static>>> {
+    // Open certificate file.
+    let certfile = fs::File::open(filename).unwrap();
+    let mut reader = io::BufReader::new(certfile);
+
+    // Load and return certificate.
+    rustls_pemfile::certs(&mut reader).collect()
+}
+
+// Load the private key from a file.
+fn load_private_key(filename: &str) -> io::Result<PrivateKeyDer<'static>> {
+    // Open keyfile.
+    let keyfile = fs::File::open(filename).unwrap();
+    let mut reader = io::BufReader::new(keyfile);
+
+    // Load and return a single private key.
+    rustls_pemfile::private_key(&mut reader).map(|key| key.unwrap())
+}