added initial RSA keypair generation

loc_chain_app/lib/pages/home.dart

@@ -0,0 +1,52 @@
+import 'package:flutter/material.dart';
+
+class HomePage extends StatefulWidget {
+  HomePage({Key key, this.title}) : super(key: key);
+  final String title;
+
+  @override
+  _HomePageState createState() => _HomePageState();
+}
+
+class _HomePageState extends State<HomePage> {
+  int _counter = 0;
+
+  void _incrementCounter() {
+    setState(() {
+      // This call to setState tells the Flutter framework that something has
+      // changed in this State, which causes it to rerun the build method below
+      // so that the display can reflect the updated values. If we changed
+      // _counter without calling setState(), then the build method would not be
+      // called again, and so nothing would appear to happen.
+      _counter++;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text(widget.title),
+      ),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: <Widget>[
+            Text(
+              'You have pushed the button this many times:',
+            ),
+            Text(
+              '$_counter',
+              style: Theme.of(context).textTheme.headline4,
+            ),
+          ],
+        ),
+      ),
+      floatingActionButton: FloatingActionButton(
+        onPressed: _incrementCounter,
+        tooltip: 'Increment',
+        child: Icon(Icons.add),
+      ),
+    );
+  }
+}

loc_chain_app/lib/pages/keygen.dart

@@ -0,0 +1,89 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:rsa_encrypt/rsa_encrypt.dart' as rsa;
+import 'package:pointycastle/api.dart' as crypto;
+
+class KeygenPage extends StatefulWidget {
+  KeygenPage({Key key, this.title}) : super(key: key);
+  final String title;
+
+  @override
+  _KeygenState createState() => _KeygenState();
+}
+
+class _KeygenState extends State<KeygenPage> {
+  static crypto.AsymmetricKeyPair _keyPair;
+
+  void _regenerateKey() {
+    setState(() {
+      _keyPair = rsa.getRsaKeyPair(rsa.RsaKeyHelper().getSecureRandom());
+    });
+  }
+
+  String _getPublicKey() {
+    if (_keyPair == null)
+      return 'Press the button below to generate your key pair!';
+    return '${rsa.RsaKeyHelper().encodePublicKeyToPemPKCS1(_keyPair.publicKey)}';
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    // This method is rerun every time setState is called, for instance as done
+    // by the _incrementCounter method above.
+    //
+    // The Flutter framework has been optimized to make rerunning build methods
+    // fast, so that you can just rebuild anything that needs updating rather
+    // than having to individually change instances of widgets.
+    return Scaffold(
+      appBar: AppBar(
+        // Here we take the value from the MyHomePage object that was created by
+        // the App.build method, and use it to set our appbar title.
+        title: Text('RSA Key Configuration'),
+      ),
+      body: Center(
+        // Center is a layout widget. It takes a single child and positions it
+        // in the middle of the parent.
+        child: Column(
+          // Column is also a layout widget. It takes a list of children and
+          // arranges them vertically. By default, it sizes itself to fit its
+          // children horizontally, and tries to be as tall as its parent.
+          //
+          // Invoke "debug painting" (press "p" in the console, choose the
+          // "Toggle Debug Paint" action from the Flutter Inspector in Android
+          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
+          // to see the wireframe for each widget.
+          //
+          // Column has various properties to control how it sizes itself and
+          // how it positions its children. Here we use mainAxisAlignment to
+          // center the children vertically; the main axis here is the vertical
+          // axis because Columns are vertical (the cross axis would be
+          // horizontal).
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: <Widget>[
+            TextButton(
+              onPressed: () => Clipboard.setData(
+                new ClipboardData(
+                  text: _getPublicKey(),
+                ),
+              ).then((_) {
+                ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+                  content: Text("RSA public key copied to keyboard"),
+                ));
+              }),
+              child: Text(
+                _getPublicKey(),
+                style: Theme.of(context).textTheme.bodyText1,
+              ),
+              style: Theme.of(context).outlinedButtonTheme.style,
+            ),
+            ElevatedButton(
+              onPressed: _regenerateKey,
+              child: Text('Reset RSA Key'),
+              style: Theme.of(context).elevatedButtonTheme.style,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}