From 26fca259bcf5afce657fee07d07a0d58191d42b7 Mon Sep 17 00:00:00 2001
From: Christian Basler <chrigu.meyer@gmail.com>
Date: Sun, 16 Apr 2017 22:38:11 +0200
Subject: [PATCH] Alternative key exchange by providing the public key in the
 URI

---
 .../apps/abit/AddressDetailFragment.java      | 16 +++++
 .../apps/abit/CreateAddressActivity.java      | 58 +++++++++++++++++--
 2 files changed, 68 insertions(+), 6 deletions(-)

diff --git a/app/src/main/java/ch/dissem/apps/abit/AddressDetailFragment.java b/app/src/main/java/ch/dissem/apps/abit/AddressDetailFragment.java
index 40b2410..95ce443 100644
--- a/app/src/main/java/ch/dissem/apps/abit/AddressDetailFragment.java
+++ b/app/src/main/java/ch/dissem/apps/abit/AddressDetailFragment.java
@@ -26,6 +26,7 @@ import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentActivity;
 import android.text.Editable;
 import android.text.TextWatcher;
+import android.util.Base64;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -48,13 +49,18 @@ import com.mikepenz.google_material_typeface_library.GoogleMaterial;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
 import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.apps.abit.util.Drawables;
 import ch.dissem.bitmessage.entity.BitmessageAddress;
+import ch.dissem.bitmessage.exception.ApplicationException;
 import ch.dissem.bitmessage.wif.WifExporter;
 
 import static android.graphics.Color.BLACK;
 import static android.graphics.Color.WHITE;
+import static android.util.Base64.URL_SAFE;
 
 
 /**
@@ -269,6 +275,16 @@ public class AddressDetailFragment extends Fragment {
         if (address.getAlias() != null) {
             link.append("?label=").append(address.getAlias());
         }
+        if (address.getPubkey() != null) {
+            link.append(address.getAlias() == null ? '?' : '&');
+            ByteArrayOutputStream pubkey = new ByteArrayOutputStream();
+            try {
+                address.getPubkey().writeUnencrypted(pubkey);
+            } catch (IOException e) {
+                throw new ApplicationException(e);
+            }
+            link.append("pubkey=").append(Base64.encodeToString(pubkey.toByteArray(), URL_SAFE));
+        }
         BitMatrix result;
         try {
             result = new MultiFormatWriter().encode(link.toString(),
diff --git a/app/src/main/java/ch/dissem/apps/abit/CreateAddressActivity.java b/app/src/main/java/ch/dissem/apps/abit/CreateAddressActivity.java
index cf5d51f..27d344d 100644
--- a/app/src/main/java/ch/dissem/apps/abit/CreateAddressActivity.java
+++ b/app/src/main/java/ch/dissem/apps/abit/CreateAddressActivity.java
@@ -20,17 +20,32 @@ import android.app.Activity;
 import android.net.Uri;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
+import android.util.Base64;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.Switch;
 import android.widget.TextView;
 
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import ch.dissem.apps.abit.service.Singleton;
 import ch.dissem.bitmessage.BitmessageContext;
 import ch.dissem.bitmessage.entity.BitmessageAddress;
+import ch.dissem.bitmessage.entity.payload.Pubkey;
+import ch.dissem.bitmessage.entity.payload.V2Pubkey;
+import ch.dissem.bitmessage.entity.payload.V3Pubkey;
+import ch.dissem.bitmessage.entity.payload.V4Pubkey;
+
+import static android.util.Base64.URL_SAFE;
 
 public class CreateAddressActivity extends AppCompatActivity {
+    private static final Pattern KEY_VALUE_PATTERN = Pattern.compile("^([a-zA-Z]+)=(.*)$");
+    private byte[] pubkeyBytes;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -48,12 +63,19 @@ public class CreateAddressActivity extends AppCompatActivity {
             String addressText = getAddress(uri);
             String[] parameters = getParameters(uri);
             for (String parameter : parameters) {
-                String name = parameter.substring(0, 6).toLowerCase();
-                if (name.startsWith("label")) {
-                    label.setText(parameter.substring(parameter.indexOf('=') + 1).trim());
-                } else if (name.startsWith("action")) {
-                    parameter = parameter.toLowerCase();
-                    subscribe.setChecked(parameter.contains("subscribe"));
+                Matcher matcher = KEY_VALUE_PATTERN.matcher(parameter);
+                String key = matcher.group(1).toLowerCase();
+                String value = matcher.group(2);
+                switch (key) {
+                    case "label":
+                        label.setText(value.trim());
+                        break;
+                    case "action":
+                        subscribe.setChecked(value.trim().equalsIgnoreCase("subscribe"));
+                        break;
+                    case "pubkey":
+                        pubkeyBytes = Base64.decode(value, URL_SAFE);
+                        break;
                 }
             }
 
@@ -83,6 +105,30 @@ public class CreateAddressActivity extends AppCompatActivity {
                     if (subscribe.isChecked()) {
                         bmc.addSubscribtion(bmAddress);
                     }
+                    if (pubkeyBytes != null) {
+                        try {
+                            final Pubkey pubkey;
+                            InputStream pubkeyStream = new ByteArrayInputStream(pubkeyBytes);
+                            long stream = bmAddress.getStream();
+                            switch ((int) bmAddress.getVersion()) {
+                                case 2:
+                                    pubkey = V2Pubkey.read(pubkeyStream, stream);
+                                    break;
+                                case 3:
+                                    pubkey = V3Pubkey.read(pubkeyStream, stream);
+                                    break;
+                                case 4:
+                                    pubkey = new V4Pubkey(V3Pubkey.read(pubkeyStream, stream));
+                                    break;
+                                default:
+                                    pubkey = null;
+                            }
+                            if (pubkey != null) {
+                                bmAddress.setPubkey(pubkey);
+                            }
+                        } catch (Exception ignore) {
+                        }
+                    }
 
                     setResult(Activity.RESULT_OK);
                     finish();