diff --git a/protocols/luci-proto-openconnect/htdocs/luci-static/resources/protocol/openconnect.js b/protocols/luci-proto-openconnect/htdocs/luci-static/resources/protocol/openconnect.js
index 05c559ce84..86ff009029 100644
--- a/protocols/luci-proto-openconnect/htdocs/luci-static/resources/protocol/openconnect.js
+++ b/protocols/luci-proto-openconnect/htdocs/luci-static/resources/protocol/openconnect.js
@@ -4,14 +4,14 @@
 'require network';
 'require validation';
 
-var callGetCertificateFiles = rpc.declare({
+const callGetCertificateFiles = rpc.declare({
 	object: 'luci.openconnect',
 	method: 'getCertificates',
 	params: [ 'interface' ],
 	expect: { '': {} }
 });
 
-var callSetCertificateFiles = rpc.declare({
+const callSetCertificateFiles = rpc.declare({
 	object: 'luci.openconnect',
 	method: 'setCertificates',
 	params: [ 'interface', 'user_certificate', 'user_privatekey', 'ca_certificate' ],
@@ -22,14 +22,14 @@ network.registerPatternVirtual(/^vpn-.+$/);
 
 function sanitizeCert(s) {
 	if (typeof(s) != 'string')
-		return null;
+		return '';
 
 	s = s.trim();
 
 	if (s == '')
-		return null;
+		return s;
 
-	s = s.replace(/\r\n?/g, '\n');
+	s = s.replace(/\r?\n/g, '\n');
 
 	if (!s.match(/\n$/))
 		s += '\n';
@@ -38,24 +38,22 @@ function sanitizeCert(s) {
 }
 
 function validateCert(priv, section_id, value) {
-	var beg = priv ? /^-----BEGIN (RSA )?PRIVATE KEY-----$/ : /^-----BEGIN CERTIFICATE-----$/,
-	    end = priv ? /^-----END (RSA )?PRIVATE KEY-----$/ : /^-----END CERTIFICATE-----$/,
-	    lines = value.trim().split(/[\r\n]/),
-	    start = false,
-	    i;
-
-	if (value === null || value === '')
+	if (!value?.trim())
 		return true;
 
-	for (i = 0; i < lines.length; i++) {
-		if (lines[i].match(beg))
-			start = true;
-		else if (start && !lines[i].match(/^(?:[A-Za-z0-9+\/]{4})*(?:[A-Za-z0-9+\/]{2}==|[A-Za-z0-9+\/]{3}=)?$/))
-			break;
-	}
+	const beg = priv ? /^-----BEGIN (RSA )?PRIVATE KEY-----$/ : /^-----BEGIN CERTIFICATE-----$/;
+	const end = priv ? /^-----END (RSA )?PRIVATE KEY-----$/ : /^-----END CERTIFICATE-----$/;
+	const lines = value.trim().split(/[\r?\n]/);
+	const base64 = /^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/;
+	const errmsg = _('This does not look like a valid PEM file');
 
-	if (!start || i < lines.length - 1 || !lines[i].match(end))
-		return _('This does not look like a valid PEM file');
+
+	if (!lines?.[0].match(beg) || !lines.at(-1).match(end))
+		return errmsg;
+
+	for (let i = 1; i < lines.length - 1; i++)
+		if (!base64.test(lines[i]))
+			return errmsg;
 
 	return true;
 }
@@ -90,9 +88,9 @@ return network.registerProtocol('openconnect', {
 	},
 
 	renderFormOptions: function(s) {
-		var dev = this.getDevice().getName(),
-		    certLoadPromise = null,
-		    o;
+		const dev = this.getDevice().getName();
+		let certLoadPromise = null;
+		let o;
 
 		o = s.taboption('general', form.ListValue, 'vpn_protocol', _('VPN Protocol'));
 		o.value('anyconnect', 'OpenConnect or Cisco AnyConnect SSL VPN');
@@ -106,7 +104,7 @@ return network.registerProtocol('openconnect', {
 		o = s.taboption('general', form.Value, 'uri', _('VPN Server'));
 		o.placeholder = 'https://example.com:443/usergroup';
 		o.validate = function(section_id, value) {
-			var m = String(value).match(/^(?:(\w+):\/\/|)(?:\[([0-9a-f:.]{2,45})\]|([^\/:]+))(?::([0-9]{1,5}))?(?:\/.*)?$/i);
+			const m = String(value).match(/^(?:(\w+):\/\/|)(?:\[([0-9a-f:.]{2,45})\]|([^\/:]+))(?::([0-9]{1,5}))?(?:\/.*)?$/i);
 
 			if (!m)
 				return _('Invalid server URL');
@@ -163,7 +161,7 @@ return network.registerProtocol('openconnect', {
 			return certLoadPromise.then(function(certs) { return certs.user_certificate });
 		};
 		o.write = function(section_id, value) {
-			return callSetCertificateFiles(section_id, sanitizeCert(value), null, null);
+			return callSetCertificateFiles(section_id, sanitizeCert(value), '', '');
 		};
 
 		o = s.taboption('general', form.TextValue, 'userkey', _('User key (PEM encoded)'));
@@ -175,7 +173,7 @@ return network.registerProtocol('openconnect', {
 			return certLoadPromise.then(function(certs) { return certs.user_privatekey });
 		};
 		o.write = function(section_id, value) {
-			return callSetCertificateFiles(section_id, null, sanitizeCert(value), null);
+			return callSetCertificateFiles(section_id, '', sanitizeCert(value), '');
 		};
 
 		o = s.taboption('general', form.TextValue, 'ca', _('CA certificate; if empty it will be saved after the first connection.'));
@@ -187,7 +185,7 @@ return network.registerProtocol('openconnect', {
 			return certLoadPromise.then(function(certs) { return certs.ca_certificate });
 		};
 		o.write = function(section_id, value) {
-			return callSetCertificateFiles(section_id, null, null, sanitizeCert(value));
+			return callSetCertificateFiles(section_id, '', '', sanitizeCert(value));
 		};
 
 		o = s.taboption('advanced', form.Value, 'mtu', _('Override MTU'));
diff --git a/protocols/luci-proto-openconnect/root/usr/share/rpcd/ucode/luci.openconnect b/protocols/luci-proto-openconnect/root/usr/share/rpcd/ucode/luci.openconnect
index 8e728e6bd0..1bc13a1706 100644
--- a/protocols/luci-proto-openconnect/root/usr/share/rpcd/ucode/luci.openconnect
+++ b/protocols/luci-proto-openconnect/root/usr/share/rpcd/ucode/luci.openconnect
@@ -1,41 +1,32 @@
-#!/usr/bin/env ucode
-
 'use strict';
 
 import { readfile, writefile, stat } from 'fs';
 
 const interfaceregex = /^[a-zA-Z0-9_]+$/;
-const user_certificate_string = "/etc/openconnect/user-cert-vpn-%s.pem";
-const user_privatekey_string = "/etc/openconnect/user-key-vpn-%s.pem";
-const ca_certificate_string = "/etc/openconnect/ca-vpn-%s.pem";
+const paths = {
+	user_certificate: "/etc/openconnect/user-cert-vpn-%s.pem",
+	user_privatekey:  "/etc/openconnect/user-key-vpn-%s.pem",
+	ca_certificate:   "/etc/openconnect/ca-vpn-%s.pem"
+};
 
-
-// Utility to read a file
 function _readfile(path) {
-	let _stat = stat(path);
-	if (_stat && _stat.type == "file") {
-		let content = readfile(path);
-		return content ? trim(content) : 'File empty';
-	}
-	return 'File not found';
+	let s = stat(path);
+	return (s?.type == 'file') ? trim(readfile(path) ?? '') || 'File empty' : null;
 }
 
-// Utility to write a file
 function _writefile(path, data) {
-	if (!data) {
-		return false;
-	}
-	return writefile(path, data) == length(data);
+	return data ? writefile(path, data) == length(data) : false;
+}
+
+function is_valid_iface(ifname) {
+	return ifname && match(ifname, interfaceregex);
 }
 
 const methods = {
-
-	list:{
+	list: {
 		call: function() {
 			return {
-				getCertificates: {
-					interface: "interface"
-				},
+				getCertificates: { interface: "interface" },
 				setCertificates: {
 					interface: "interface",
 					user_certificate: "user_certificate",
@@ -47,29 +38,16 @@ const methods = {
 	},
 
 	getCertificates: {
-		args: {
-			interface: "interface",
-		},
+		args: { interface: "interface" },
 		call: function(req) {
+			let iface = req.args?.interface;
+			if (!is_valid_iface(iface)) return;
 
-			const _interface = req.args?.interface;
-			if (!_interface || !match(_interface, interfaceregex)) {
-				// printf("Invalid interface name");
-				return;
-			}
-
-			const user_certificate_pem = _readfile(sprintf(user_certificate_string, _interface));
-			const user_privatekey_pem = _readfile(sprintf(user_privatekey_string, _interface));
-			const ca_certificate_pem = _readfile(sprintf(ca_certificate_string, _interface));
-
-			if(user_certificate_pem && user_privatekey_pem && ca_certificate_pem){
-				return {
-					user_certificate: user_certificate_pem,
-					user_privatekey: user_privatekey_pem,
-					ca_certificate: ca_certificate_pem,
-				};
-			}
+			let result = {};
+			for (let k in paths)
+				result[k] = _readfile(sprintf(paths[k], iface));
 
+			return result;
 		}
 	},
 
@@ -81,35 +59,17 @@ const methods = {
 			ca_certificate: "ca_certificate",
 		},
 		call: function(req) {
+			let iface = req.args?.interface;
+			if (!is_valid_iface(iface)) return;
 
 			let result = false;
-			let _interface = req.args?.interface;
-
-			if (!_interface || !match(_interface, interfaceregex)) {
-				// printf("Invalid interface name");
-				return;
+			for (let k in paths) {
+				if (req.args?.[k])
+					result = _writefile(sprintf(paths[k], iface), req.args[k]);
 			}
-
-			/* the interface is set up to call 1 write per certificate,
-			with only one of the following arguments not null */
-			if (req.args?.user_certificate) {
-				result = _writefile(sprintf(user_certificate_string, _interface), req.args?.user_certificate);
-			}
-			if (req.args?.user_privatekey) {
-				result = _writefile(sprintf(user_privatekey_string, _interface), req.args?.user_privatekey);
-			}
-			if (req.args?.ca_certificate) {
-				result = _writefile(sprintf(ca_certificate_string, _interface), req.args?.ca_certificate);
-			}
-
-			return {
-				result: result,
-			};
-
+			return { result: result };
 		}
 	}
-
 };
 
 return { 'luci.openconnect': methods };
-