From 929a01c92c9cbf4b1879a1c1c7115d67bc2b5abe Mon Sep 17 00:00:00 2001
From: Alexander Munch-Hansen <alexmunchhansen@gmail.com>
Date: Sun, 1 Dec 2019 15:13:08 +0100
Subject: [PATCH] simple block scheme

---
 pir/src/main/java/dk/au/pir/Driver.java       | 19 ++++++-
 .../au/pir/protocols/simple/SimpleClient.java | 49 ++++++++++++++-----
 .../au/pir/protocols/simple/SimpleServer.java | 19 +++++--
 3 files changed, 71 insertions(+), 16 deletions(-)

diff --git a/pir/src/main/java/dk/au/pir/Driver.java b/pir/src/main/java/dk/au/pir/Driver.java
index 59ec071..6bd8c4c 100644
--- a/pir/src/main/java/dk/au/pir/Driver.java
+++ b/pir/src/main/java/dk/au/pir/Driver.java
@@ -29,6 +29,23 @@ public class Driver {
         return res;
     }
 
+    private static int[] simpleBlockScheme(int record) {
+        PIRSettings settings = new PIRSettings(8, 2, 2);
+        SimpleDatabase database = new SimpleDatabase(settings, new int[] {0, 0, 1, 1, 0, 0, 0, 0});
+
+        SimpleServer[] servers = new SimpleServer[settings.getNumServers()];
+
+        for (int i = 0; i < settings.getNumServers(); i++) {
+            servers[i] = new SimpleServer(database, settings);
+        }
+
+        SimpleClient client = new SimpleClient(settings, servers);
+
+        int[] res = client.receiveBits(record);
+        System.out.println("res: " + Arrays.toString(res));
+        return res;
+    }
+
 
     private static int[] generalInterPolyTest(int index) {
         PIRSettings settings = new PIRSettings(8, 3, 1);
@@ -87,7 +104,7 @@ public class Driver {
 
     public static void main(String[] args) {
         // generalBlockInterPolyTestButBetter(1);
-        simpleScheme(2);
+        simpleBlockScheme(1);
         /*
         int sum = 0;
         for (int i = 0; i < 1; i++) {
diff --git a/pir/src/main/java/dk/au/pir/protocols/simple/SimpleClient.java b/pir/src/main/java/dk/au/pir/protocols/simple/SimpleClient.java
index ca7ebbe..b880c26 100644
--- a/pir/src/main/java/dk/au/pir/protocols/simple/SimpleClient.java
+++ b/pir/src/main/java/dk/au/pir/protocols/simple/SimpleClient.java
@@ -19,34 +19,61 @@ public class SimpleClient {
         this.servers = servers;
     }
 
-    public ArrayList<Integer> selectIndexes() {
-        ArrayList<Integer> indexes = new ArrayList<>();
+    public int[] selectIndexes() {
+        int[] indexes = new int[settings.getDatabaseSize()];
         Random rand = new Random();
         for (int i=0; i < settings.getDatabaseSize(); i++) {
-            if (rand.nextInt(2) == 1) {
-                indexes.add(i);
-            }
+            indexes[i] = rand.nextInt(2);
         }
         return indexes;
     }
 
 
     public int receiveBit(int index) {
-        ArrayList<Integer> S1 = selectIndexes();
-        ArrayList<Integer> S2 = (ArrayList<Integer>) S1.clone();
+        int[] S1 = selectIndexes();
+        int[] S2 = S1.clone();
 
-        if (S1.contains(index)) {
+        if (S1[index] == 1) {
             // Remove the index, if it's contained in S.
-            S2.remove((Integer) index);
+            S2[index] = 0;
         } else {
-            S2.add(index);
+            S2[index] = 1;
         }
 
-
         // TODO: Hardcoded, should be a loop
         int resBit1 = this.servers[0].computeBit(S1);
         int resBit2 = this.servers[1].computeBit(S2);
 
         return ((resBit1 + resBit2) % 2);
     }
+
+    public int[] receiveBits(int record) {
+        int[] result = new int[settings.getBlocksize()];
+
+        int[][] S1s = new int[settings.getBlocksize()][settings.getDatabaseSize()];
+        int[][] S2s = new int[settings.getBlocksize()][settings.getDatabaseSize()];
+
+        for (int i = 0; i < settings.getBlocksize(); i++) {
+            S1s[i] = selectIndexes();
+            S2s[i] = S1s[i].clone();
+
+            if (S1s[i][(record*settings.getBlocksize())+i] == 1) {
+                // Remove the index, if it's contained in S.
+                S2s[i][(record*settings.getBlocksize())+i] = 0;
+            } else {
+                S2s[i][(record*settings.getBlocksize())+i] = 1;
+            }
+        }
+
+
+        int[] resBit1 = this.servers[0].computeBits(S1s);
+        int[] resBit2 = this.servers[1].computeBits(S2s);
+
+        for (int i = 0; i < settings.getBlocksize(); i++) {
+            result[i] = (resBit1[i] + resBit2[i]) % 2;
+        }
+
+        return result;
+
+    }
 }
diff --git a/pir/src/main/java/dk/au/pir/protocols/simple/SimpleServer.java b/pir/src/main/java/dk/au/pir/protocols/simple/SimpleServer.java
index b2b1b2a..ddd9ab8 100644
--- a/pir/src/main/java/dk/au/pir/protocols/simple/SimpleServer.java
+++ b/pir/src/main/java/dk/au/pir/protocols/simple/SimpleServer.java
@@ -16,11 +16,22 @@ public class SimpleServer {
         this.x = database.getX();
     }
 
-    public int computeBit(ArrayList<Integer> indexes) {
-        int res = x[indexes.get(0)];
-        for (int index : indexes.subList(1, indexes.size())) {
-            res = (res + x[index]) % 2;
+    public int computeBit(int[] indexes) {
+        int res = x[indexes[0]];
+        for (int i=1; i<indexes.length; i++) {
+            if (indexes[i] == 1)
+                res = (res + x[i]) % 2;
         }
         return res;
     }
+
+
+    public int[] computeBits(int[][] indexes) {
+        int[] res = new int[settings.getBlocksize()];
+        for (int i = 0; i < settings.getBlocksize(); i++) {
+            res[i] = computeBit(indexes[i]);
+        }
+        return res;
+    }
+
 }