Support replacing certs (#33)

android/app/src/main/kotlin/net/defined/mobile_nebula/Sites.kt

@@ -263,9 +263,11 @@ class IncomingSite(
         }
 
         if (key != null) {
-            val f = EncFile(context).openWrite(siteDir.resolve("key"))
+            val keyFile = siteDir.resolve("key")
-            f.use { it.write(key) }
+            keyFile.delete()
-            f.close()
+            val encFile = EncFile(context).openWrite(keyFile)
+            encFile.use { it.write(key) }
+            encFile.close()
         }
 
         key = null

lib/components/FormPage.dart

@@ -8,12 +8,13 @@ import 'package:mobile_nebula/services/utils.dart';
 /// SimplePage with a form and built in validation and confirmation to discard changes if any are made
 class FormPage extends StatefulWidget {
   const FormPage(
-      {Key key, this.title, @required this.child, @required this.onSave, @required this.changed, this.hideSave = false})
+      {Key key, this.title, @required this.child, @required this.onSave, @required this.changed, this.hideSave = false, this.scrollController})
       : super(key: key);
 
   final String title;
   final Function onSave;
   final Widget child;
+  final ScrollController scrollController;
 
   /// If you need the page to progress to a certain point before saving, control it here
   final bool hideSave;
@@ -50,6 +51,7 @@ class _FormPageState extends State<FormPage> {
         child: SimplePage(
           leadingAction: _buildLeader(context),
           trailingActions: _buildTrailer(context),
+          scrollController: widget.scrollController,
           title: widget.title,
           child: Form(
               key: _formKey,

lib/components/SiteItem.dart

@@ -28,8 +28,8 @@ class SiteItem extends StatelessWidget {
   Widget _buildContent(BuildContext context) {
     final border = BorderSide(color: Utils.configSectionBorder(context));
     var ip = "Error";
-    if (site.cert != null && site.cert.cert.details.ips.length > 0) {
+    if (site.certInfo != null && site.certInfo.cert.details.ips.length > 0) {
-      ip = site.cert.cert.details.ips[0];
+      ip = site.certInfo.cert.details.ips[0];
     }
 
     return SpecialButton(

lib/models/IPAndPort.dart

@@ -1,5 +1,3 @@
-import 'dart:io';
-
 class IPAndPort {
   String ip;
   int port;

lib/models/Site.dart

@@ -27,7 +27,7 @@ class Site {
 
   // pki fields
   List<CertificateInfo> ca;
-  CertificateInfo cert;
+  CertificateInfo certInfo;
   String key;
 
   // lighthouse options
@@ -52,7 +52,7 @@ class Site {
       id,
       staticHostmap,
       ca,
-      this.cert,
+      this.certInfo,
       this.lhDuration = 0,
       this.port = 0,
       this.cipher = "aes",
@@ -95,7 +95,7 @@ class Site {
     });
 
     if (json['cert'] != null) {
-      cert = CertificateInfo.fromJson(json['cert']);
+      certInfo = CertificateInfo.fromJson(json['cert']);
     }
 
     lhDuration = json['lhDuration'];
@@ -146,7 +146,7 @@ class Site {
             return cert.rawCert;
           })?.join('\n') ??
           "",
-      'cert': cert?.rawCert,
+      'cert': certInfo?.rawCert,
       'key': key,
       'lhDuration': lhDuration,
       'port': port,

lib/screens/HostInfoScreen.dart

@@ -68,7 +68,7 @@ class _HostInfoScreenState extends State<HostInfoScreen> {
               labelWidth: 150,
               content: Text(hostInfo.cert.details.name),
               onPressed: () => Utils.openPage(
-                  context, (context) => CertificateDetailsScreen(certificate: CertificateInfo(cert: hostInfo.cert))))
+                  context, (context) => CertificateDetailsScreen(certInfo: CertificateInfo(cert: hostInfo.cert))))
           : Container(),
     ]);
   }

lib/screens/MainScreen.dart

@@ -179,7 +179,7 @@ mUOcsdFcCZiXrj7ryQIG1+WfqA46w71A/lV4nAc=
             "10.1.0.1": StaticHost(lighthouse: true, destinations: [IPAndPort(ip: '10.1.1.53', port: 4242), IPAndPort(ip: '1::1', port: 4242)])
           },
           ca: [CertificateInfo.debug(rawCert: ca)],
-          cert: CertificateInfo.debug(rawCert: cert),
+          certInfo: CertificateInfo.debug(rawCert: cert),
           unsafeRoutes: [UnsafeRoute(route: '10.3.3.3/32', via: '10.1.0.1')]
         );
 

lib/screens/siteConfig/AddCertificateScreen.dart

@@ -1,56 +1,54 @@
 import 'dart:convert';
 
 import 'package:barcode_scan/barcode_scan.dart';
-import 'package:file_picker/file_picker.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
-import 'package:mobile_nebula/components/FormPage.dart';
+import 'package:flutter_platform_widgets/flutter_platform_widgets.dart';
+import 'package:mobile_nebula/components/SimplePage.dart';
 import 'package:mobile_nebula/components/SpecialSelectableText.dart';
 import 'package:mobile_nebula/components/config/ConfigButtonItem.dart';
 import 'package:mobile_nebula/components/config/ConfigItem.dart';
-import 'package:mobile_nebula/components/config/ConfigPageItem.dart';
 import 'package:mobile_nebula/components/config/ConfigSection.dart';
 import 'package:mobile_nebula/components/config/ConfigTextItem.dart';
 import 'package:mobile_nebula/models/Certificate.dart';
-import 'package:mobile_nebula/screens/siteConfig/CertificateDetailsScreen.dart';
 import 'package:mobile_nebula/services/share.dart';
 import 'package:mobile_nebula/services/utils.dart';
 
+import 'CertificateDetailsScreen.dart';
+
 class CertificateResult {
-  CertificateInfo cert;
+  CertificateInfo certInfo;
   String key;
 
-  CertificateResult({this.cert, this.key});
+  CertificateResult({this.certInfo, this.key});
 }
 
-class CertificateScreen extends StatefulWidget {
+class AddCertificateScreen extends StatefulWidget {
-  const CertificateScreen({Key key, this.cert, this.onSave}) : super(key: key);
+  const AddCertificateScreen({Key key, this.onSave, this.onReplace}) : super(key: key);
 
-  final CertificateInfo cert;
+  // onSave will pop a new CertificateDetailsScreen
   final ValueChanged<CertificateResult> onSave;
+  // onReplace will return the CertificateResult, assuming the previous screen is a CertificateDetailsScreen
+  final ValueChanged<CertificateResult> onReplace;
 
   @override
-  _CertificateScreenState createState() => _CertificateScreenState();
+  _AddCertificateScreenState createState() => _AddCertificateScreenState();
 }
 
-class _CertificateScreenState extends State<CertificateScreen> {
+class _AddCertificateScreenState extends State<AddCertificateScreen> {
   String pubKey;
   String privKey;
-  bool changed = false;
-
-  CertificateInfo cert;
 
   String inputType = 'paste';
-  bool shared = false;
 
   final pasteController = TextEditingController();
   static const platform = MethodChannel('net.defined.mobileNebula/NebulaVpnService');
 
   @override
   void initState() {
-    cert = widget.cert;
+    _generateKeys();
     super.initState();
   }
 
@@ -62,71 +60,29 @@ class _CertificateScreenState extends State<CertificateScreen> {
 
   @override
   Widget build(BuildContext context) {
-    List<Widget> items = [];
+    if (pubKey == null) {
-    bool hideSave = true;
+      return Center(
-
+        child: PlatformCircularProgressIndicator(cupertino: (_, __) {
-    if (cert == null) {
+          return CupertinoProgressIndicatorData(radius: 500);
-      if (pubKey == null) {
+        }),
-        items = _buildGenerate();
+      );
-      } else {
-        items.addAll(_buildShare());
-        items.addAll(_buildLoadCert());
-      }
-    } else {
-      items.addAll(_buildCertList());
-      hideSave = false;
     }
 
-    return FormPage(
+    List<Widget> items = [];
+    items.addAll(_buildShare());
+    items.addAll(_buildLoadCert());
+
+    return SimplePage(
         title: 'Certificate',
-        changed: changed,
-        hideSave: hideSave,
-        onSave: () {
-          Navigator.pop(context);
-          if (widget.onSave != null) {
-            widget.onSave(CertificateResult(cert: cert, key: privKey));
-          }
-        },
         child: Column(children: items));
   }
 
-  _buildCertList() {
-    //TODO: generate a full list
-    return [
-      ConfigSection(
-        children: [
-          ConfigPageItem(
-            content: Text(cert.cert.details.name),
-            onPressed: () {
-              Utils.openPage(context, (context) {
-                //TODO: wire on delete
-                return CertificateDetailsScreen(certificate: cert);
-              });
-            },
-          )
-        ],
-      )
-    ];
-  }
-
-  List<Widget> _buildGenerate() {
-    return [
-      ConfigSection(label: 'Please generate a new public and private key', children: [
-        ConfigButtonItem(
-          content: Text('Generate Keys'),
-          onPressed: () => _generateKeys(),
-        )
-      ])
-    ];
-  }
-
   _generateKeys() async {
     try {
       var kp = await platform.invokeMethod("nebula.generateKeyPair");
       Map<String, dynamic> keyPair = jsonDecode(kp);
 
       setState(() {
-        changed = true;
         pubKey = keyPair['PublicKey'];
         privKey = keyPair['PrivateKey'];
       });
@@ -148,9 +104,6 @@ class _CertificateScreenState extends State<CertificateScreen> {
               content: Text('Share Public Key'),
               onPressed: () async {
                 await Share.share(title: 'Please sign and return a certificate', text: pubKey, filename: 'device.pub');
-                setState(() {
-                  shared = true;
-                });
               },
             ),
           ])
@@ -198,14 +151,7 @@ class _CertificateScreenState extends State<CertificateScreen> {
           ConfigButtonItem(
               content: Center(child: Text('Load Certificate')),
               onPressed: () {
-                _addCertEntry(pasteController.text, (err) {
+                _addCertEntry(pasteController.text);
-                  if (err != null) {
-                    return Utils.popError(context, 'Failed to parse certificate content', err);
-                  }
-
-                  pasteController.text = '';
-                  setState(() {});
-                });
               }),
         ],
       )
@@ -225,13 +171,7 @@ class _CertificateScreenState extends State<CertificateScreen> {
                     return;
                   }
 
-                  _addCertEntry(content, (err) {
+                  _addCertEntry(content);
-                    if (err != null) {
-                      Utils.popError(context, 'Error loading certificate file', err);
-                    } else {
-                      setState(() {});
-                    }
-                  });
                 } catch (err) {
                   return Utils.popError(context, 'Failed to load certificate file', err.toString());
                 }
@@ -254,13 +194,7 @@ class _CertificateScreenState extends State<CertificateScreen> {
 
                 var result = await BarcodeScanner.scan(options: options);
                 if (result.rawContent != "") {
-                  _addCertEntry(result.rawContent, (err) {
+                  _addCertEntry(result.rawContent);
-                    if (err != null) {
-                      Utils.popError(context, 'Error loading certificate content', err);
-                    } else {
-                      setState(() {});
-                    }
-                  });
                 }
               }),
         ],
@@ -268,9 +202,7 @@ class _CertificateScreenState extends State<CertificateScreen> {
     ];
   }
 
-  _addCertEntry(String rawCert, ValueChanged<String> callback) async {
+  _addCertEntry(String rawCert) async {
-    String error;
-
     // Allow for app store review testing cert to override the generated key
     if (rawCert.trim() == _testCert) {
       privKey = _testKey;
@@ -278,21 +210,36 @@ class _CertificateScreenState extends State<CertificateScreen> {
 
     try {
       var rawCerts = await platform.invokeMethod("nebula.parseCerts", <String, String>{"certs": rawCert});
+
       List<dynamic> certs = jsonDecode(rawCerts);
       if (certs.length > 0) {
-        var tryCert = CertificateInfo.fromJson(certs.first);
+        var tryCertInfo = CertificateInfo.fromJson(certs.first);
-        if (tryCert.cert.details.isCa) {
+        if (tryCertInfo.cert.details.isCa) {
-          return callback('A certificate authority is not appropriate for a client certificate.');
+          return Utils.popError(context, 'Error loading certificate content', 'A certificate authority is not appropriate for a client certificate.');
+
+        } else if (!tryCertInfo.validity.valid) {
+          return Utils.popError(context, 'Certificate was invalid', tryCertInfo.validity.reason);
         }
-        //TODO: test that the pubkey matches the privkey
+
-        cert = tryCert;
+        //TODO: test that the pubkey we generated equals the pub key in the cert
+
+        // If we are replacing we just return the results now
+        if (widget.onReplace != null) {
+          Navigator.pop(context);
+          widget.onReplace(CertificateResult(certInfo: tryCertInfo, key: privKey));
+          return;
+        }
+
+        // We have a cert, pop the details screen where they can hit save
+        Utils.openPage(context, (context) {
+          return CertificateDetailsScreen(certInfo: tryCertInfo, onSave: () {
+            Navigator.pop(context);
+            widget.onSave(CertificateResult(certInfo: tryCertInfo, key: privKey));
+          });
+        });
       }
     } on PlatformException catch (err) {
-      error = err.details ?? err.message;
+      return Utils.popError(context, 'Error loading certificate content', err.details ?? err.message);
-    }
-
-    if (callback != null) {
-      callback(error);
     }
   }
 }

lib/screens/siteConfig/CAListScreen.dart

@@ -77,7 +77,7 @@ class _CAListScreenState extends State<CAListScreen> {
         onPressed: () {
           Utils.openPage(context, (context) {
             return CertificateDetailsScreen(
-                certificate: ca,
+                certInfo: ca,
                 onDelete: () {
                   setState(() {
                     changed = true;

lib/screens/siteConfig/CertificateDetailsScreen.dart

@@ -2,34 +2,73 @@ import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_platform_widgets/flutter_platform_widgets.dart';
-import 'package:mobile_nebula/components/SimplePage.dart';
+import 'package:mobile_nebula/components/FormPage.dart';
 import 'package:mobile_nebula/components/SpecialSelectableText.dart';
 import 'package:mobile_nebula/components/config/ConfigItem.dart';
 import 'package:mobile_nebula/components/config/ConfigSection.dart';
 import 'package:mobile_nebula/models/Certificate.dart';
+import 'package:mobile_nebula/screens/siteConfig/AddCertificateScreen.dart';
 import 'package:mobile_nebula/services/utils.dart';
 
 /// Displays the details of a CertificateInfo object. Respects incomplete objects (missing validity or rawCert)
 class CertificateDetailsScreen extends StatefulWidget {
-  const CertificateDetailsScreen({Key key, this.certificate, this.onDelete}) : super(key: key);
+  const CertificateDetailsScreen({Key key, this.certInfo, this.onDelete, this.onSave, this.onReplace}) : super(key: key);
 
-  final CertificateInfo certificate;
+  final CertificateInfo certInfo;
+
+  // onDelete is used to remove a CA cert
   final Function onDelete;
 
+  // onSave is used to install a new certificate
+  final Function onSave;
+
+  // onReplace is used to install a new certificate over top of the old one
+  final ValueChanged<CertificateResult> onReplace;
+
   @override
   _CertificateDetailsScreenState createState() => _CertificateDetailsScreenState();
 }
 
 class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
+  bool changed = false;
+  CertificateResult certResult;
+  CertificateInfo certInfo;
+  ScrollController controller = ScrollController();
+
+  @override
+  void initState() {
+    certInfo = widget.certInfo;
+    super.initState();
+  }
+
+  @override
+  void dispose() {
+    controller.dispose();
+    super.dispose();
+  }
+
   @override
   Widget build(BuildContext context) {
-    return SimplePage(
+    return FormPage(
       title: 'Certificate Details',
+      scrollController: controller,
+      changed: widget.onSave != null || changed,
+      onSave: () {
+        if (widget.onSave != null) {
+          Navigator.pop(context);
+          widget.onSave();
+        } else if (widget.onReplace != null) {
+          Navigator.pop(context);
+          widget.onReplace(certResult);
+        }
+      },
+      hideSave: widget.onSave == null && widget.onReplace == null,
       child: Column(children: [
         _buildID(),
         _buildFilters(),
         _buildValid(),
         _buildAdvanced(),
+        _buildReplace(),
         _buildDelete(),
       ]),
     );
@@ -37,17 +76,17 @@ class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
 
   Widget _buildID() {
     return ConfigSection(children: <Widget>[
-      ConfigItem(label: Text('Name'), content: SpecialSelectableText(widget.certificate.cert.details.name)),
+      ConfigItem(label: Text('Name'), content: SpecialSelectableText(certInfo.cert.details.name)),
       ConfigItem(
           label: Text('Type'),
-          content: Text(widget.certificate.cert.details.isCa ? 'CA certificate' : 'Client certificate')),
+          content: Text(certInfo.cert.details.isCa ? 'CA certificate' : 'Client certificate')),
     ]);
   }
 
   Widget _buildValid() {
     var valid = Text('yes');
-    if (widget.certificate.validity != null && !widget.certificate.validity.valid) {
+    if (certInfo.validity != null && !certInfo.validity.valid) {
-      valid = Text(widget.certificate.validity.valid ? 'yes' : widget.certificate.validity.reason,
+      valid = Text(certInfo.validity.valid ? 'yes' : certInfo.validity.reason,
           style: TextStyle(color: CupertinoColors.systemRed.resolveFrom(context)));
     }
     return ConfigSection(
@@ -56,33 +95,33 @@ class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
         ConfigItem(label: Text('Valid?'), content: valid),
         ConfigItem(
             label: Text('Created'),
-            content: SpecialSelectableText(widget.certificate.cert.details.notBefore.toLocal().toString())),
+            content: SpecialSelectableText(certInfo.cert.details.notBefore.toLocal().toString())),
         ConfigItem(
             label: Text('Expires'),
-            content: SpecialSelectableText(widget.certificate.cert.details.notAfter.toLocal().toString())),
+            content: SpecialSelectableText(certInfo.cert.details.notAfter.toLocal().toString())),
       ],
     );
   }
 
   Widget _buildFilters() {
     List<Widget> items = [];
-    if (widget.certificate.cert.details.groups.length > 0) {
+    if (certInfo.cert.details.groups.length > 0) {
       items.add(ConfigItem(
-          label: Text('Groups'), content: SpecialSelectableText(widget.certificate.cert.details.groups.join(', '))));
+          label: Text('Groups'), content: SpecialSelectableText(certInfo.cert.details.groups.join(', '))));
     }
 
-    if (widget.certificate.cert.details.ips.length > 0) {
+    if (certInfo.cert.details.ips.length > 0) {
       items
-          .add(ConfigItem(label: Text('IPs'), content: SpecialSelectableText(widget.certificate.cert.details.ips.join(', '))));
+          .add(ConfigItem(label: Text('IPs'), content: SpecialSelectableText(certInfo.cert.details.ips.join(', '))));
     }
 
-    if (widget.certificate.cert.details.subnets.length > 0) {
+    if (certInfo.cert.details.subnets.length > 0) {
       items.add(ConfigItem(
-          label: Text('Subnets'), content: SpecialSelectableText(widget.certificate.cert.details.subnets.join(', '))));
+          label: Text('Subnets'), content: SpecialSelectableText(certInfo.cert.details.subnets.join(', '))));
     }
 
     return items.length > 0
-        ? ConfigSection(label: widget.certificate.cert.details.isCa ? 'FILTERS' : 'DETAILS', children: items)
+        ? ConfigSection(label: certInfo.cert.details.isCa ? 'FILTERS' : 'DETAILS', children: items)
         : Container();
   }
 
@@ -91,18 +130,18 @@ class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
       children: <Widget>[
         ConfigItem(
             label: Text('Fingerprint'),
-            content: SpecialSelectableText(widget.certificate.cert.fingerprint,
+            content: SpecialSelectableText(certInfo.cert.fingerprint,
                 style: TextStyle(fontFamily: 'RobotoMono', fontSize: 14)),
             crossAxisAlignment: CrossAxisAlignment.start),
         ConfigItem(
             label: Text('Public Key'),
-            content: SpecialSelectableText(widget.certificate.cert.details.publicKey,
+            content: SpecialSelectableText(certInfo.cert.details.publicKey,
                 style: TextStyle(fontFamily: 'RobotoMono', fontSize: 14)),
             crossAxisAlignment: CrossAxisAlignment.start),
-        widget.certificate.rawCert != null
+        certInfo.rawCert != null
             ? ConfigItem(
                 label: Text('PEM Format'),
-                content: SpecialSelectableText(widget.certificate.rawCert,
+                content: SpecialSelectableText(certInfo.rawCert,
                     style: TextStyle(fontFamily: 'RobotoMono', fontSize: 14)),
                 crossAxisAlignment: CrossAxisAlignment.start)
             : Container(),
@@ -110,12 +149,40 @@ class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
     );
   }
 
+  Widget _buildReplace() {
+    if (widget.onReplace == null) {
+      return Container();
+    }
+
+    return Padding(
+      padding: EdgeInsets.only(top: 50, bottom: 10, left: 10, right: 10),
+      child: SizedBox(
+        width: double.infinity,
+        child: PlatformButton(
+          child: Text('Replace certificate'),
+          color: CupertinoColors.systemRed.resolveFrom(context),
+          onPressed: () {
+            Utils.openPage(context, (context) {
+              return AddCertificateScreen(
+                  onReplace: (result) {
+                    setState(() {
+                      changed = true;
+                      certResult = result;
+                      certInfo = certResult.certInfo;
+                    });
+                    // Slam the page back to the top
+                    controller.animateTo(0, duration: const Duration(milliseconds: 10), curve: Curves.linearToEaseOut);
+                  });
+                });
+          })));
+  }
+
   Widget _buildDelete() {
     if (widget.onDelete == null) {
       return Container();
     }
 
-    var title = widget.certificate.cert.details.isCa ? 'Delete CA?' : 'Delete cert?';
+    var title = certInfo.cert.details.isCa ? 'Delete CA?' : 'Delete cert?';
 
     return Padding(
         padding: EdgeInsets.only(top: 50, bottom: 10, left: 10, right: 10),

lib/screens/siteConfig/SiteConfigScreen.dart

@@ -13,11 +13,13 @@ import 'package:mobile_nebula/components/config/ConfigSection.dart';
 import 'package:mobile_nebula/models/Site.dart';
 import 'package:mobile_nebula/screens/siteConfig/AdvancedScreen.dart';
 import 'package:mobile_nebula/screens/siteConfig/CAListScreen.dart';
-import 'package:mobile_nebula/screens/siteConfig/CertificateScreen.dart';
+import 'package:mobile_nebula/screens/siteConfig/AddCertificateScreen.dart';
+import 'package:mobile_nebula/screens/siteConfig/CertificateDetailsScreen.dart';
 import 'package:mobile_nebula/screens/siteConfig/StaticHostsScreen.dart';
 import 'package:mobile_nebula/services/utils.dart';
 
 //TODO: Add a config test mechanism
+//TODO: Enforce a name
 
 class SiteConfigScreen extends StatefulWidget {
   const SiteConfigScreen({Key key, this.site, this.onSave}) : super(key: key);
@@ -100,12 +102,18 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
           content: PlatformTextFormField(
             placeholder: 'Required',
             controller: nameController,
+            validator: (name) {
+              if (name == null || name == "") {
+                return "A name is required";
+              }
+              return null;
+            },
           ))
     ]);
   }
 
   Widget _keys() {
-    final certError = site.cert == null || !site.cert.validity.valid;
+    final certError = site.certInfo == null || !site.certInfo.validity.valid;
     var caError = site.ca.length == 0;
     if (!caError) {
       site.ca.forEach((ca) {
@@ -126,16 +134,28 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
                     child: Icon(Icons.error, color: CupertinoColors.systemRed.resolveFrom(context), size: 20),
                     padding: EdgeInsets.only(right: 5))
                 : Container(),
-            certError ? Text('Needs attention') : Text(site.cert.cert.details.name)
+            certError ? Text('Needs attention') : Text(site.certInfo.cert.details.name)
           ]),
           onPressed: () {
             Utils.openPage(context, (context) {
-              return CertificateScreen(
+              if (site.certInfo != null) {
-                  cert: site.cert,
+                return CertificateDetailsScreen(
+                  certInfo: site.certInfo,
+                  onReplace: (result) {
+                    setState(() {
+                      changed = true;
+                      site.certInfo = result.certInfo;
+                      site.key = result.key;
+                    });
+                  }
+                );
+              }
+
+              return AddCertificateScreen(
                   onSave: (result) {
                     setState(() {
                       changed = true;
-                      site.cert = result.cert;
+                      site.certInfo = result.certInfo;
                       site.key = result.key;
                     });
                   });