package iotcloud;
import java.util.HashMap;
+import java.util.Map;
+import java.util.Iterator;
+import java.util.HashSet;
import java.util.Arrays;
import java.util.Vector;
-import javax.crypto.spec.*;
-import javax.crypto.*;
+import java.util.Random;
+
+/**
+ * IoTTable data structure. Provides client inferface.
+ * @author Brian Demsky
+ * @version 1.0
+ */
final public class Table {
private int numslots;
private HashMap<IoTString, KeyValue> table=new HashMap<IoTString, KeyValue>();
private HashMap<Long, Pair<Long, Liveness> > lastmessagetable=new HashMap<Long, Pair<Long, Liveness> >();
+ private HashMap<Long, HashSet<RejectedMessage> > watchlist = new HashMap<Long, HashSet<RejectedMessage> >();
+ private Vector<Long> rejectedmessagelist=new Vector<Long>();
private SlotBuffer buffer;
private CloudComm cloud;
- private Mac hmac;
private long sequencenumber;
private long localmachineid;
- private TableStatus lastTableStatus;
- static final int FREE_SLOTS = 10;
- static final int FORCED_RESIZE_INCREMENT = 20;
-
+ private TableStatus lastTableStatus;
+ static final int FREE_SLOTS = 10;
+ static final int SKIP_THRESHOLD = 10;
+ private long liveslotcount=0;
+ private int chance;
+ static final double RESIZE_MULTIPLE = 1.2;
+ static final double RESIZE_THRESHOLD = 0.75;
+ static final int REJECTED_THRESHOLD = 5;
+ private int resizethreshold;
+ private long lastliveslotseqn;
+ private Random random=new Random();
+
public Table(String baseurl, String password, long _localmachineid) {
localmachineid=_localmachineid;
buffer = new SlotBuffer();
numslots = buffer.capacity();
- sequencenumber = 1;
- initCloud(baseurl, password);
+ setResizeThreshold();
+ sequencenumber = 0;
+ cloud=new CloudComm(this, baseurl, password);
+ lastliveslotseqn = 1;
}
public Table(CloudComm _cloud, long _localmachineid) {
localmachineid=_localmachineid;
buffer = new SlotBuffer();
- sequencenumber = 1;
+ numslots = buffer.capacity();
+ setResizeThreshold();
+ sequencenumber = 0;
cloud=_cloud;
}
-
- private void initCloud(String baseurl, String password) {
- try {
- SecretKeySpec secret=getKey(password);
- Cipher encryptCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
- encryptCipher.init(Cipher.ENCRYPT_MODE, secret);
- Cipher decryptCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
- decryptCipher.init(Cipher.DECRYPT_MODE, secret);
- hmac = Mac.getInstance("HmacSHA256");
- hmac.init(secret);
- cloud=new CloudComm(baseurl, encryptCipher, decryptCipher, hmac);
- } catch (Exception e) {
- throw new Error("Failed To Initialize Ciphers");
- }
- }
- private SecretKeySpec getKey(String password) {
- try {
- PBEKeySpec keyspec = new PBEKeySpec(password.toCharArray());
- SecretKey key = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256").generateSecret(keyspec);
- SecretKeySpec secret = new SecretKeySpec(key.getEncoded(), "AES");
- return secret;
- } catch (Exception e) {
- throw new Error("Failed generating key.");
- }
+ public void rebuild() {
+ Slot[] newslots=cloud.getSlots(sequencenumber+1);
+ validateandupdate(newslots, true);
}
public void update() {
- Slot[] newslots=cloud.getSlots(sequencenumber);
- validateandupdate(newslots);
+ Slot[] newslots=cloud.getSlots(sequencenumber+1);
+
+ validateandupdate(newslots, false);
}
public IoTString get(IoTString key) {
}
public void initTable() {
- Slot s=new Slot(1, localmachineid);
+ cloud.setSalt();//Set the salt
+ Slot s=new Slot(this, 1, localmachineid);
TableStatus status=new TableStatus(s, numslots);
s.addEntry(status);
- Slot[] array=cloud.putSlot(s, numslots);
- if (array == null) {
- array = new Slot[] {s};
- validateandupdate(array); // update data structure
+ Slot[] array=cloud.putSlot(s, numslots);
+ if (array == null) {
+ array = new Slot[] {s};
+ /* update data structure */
+ validateandupdate(array, true);
} else {
throw new Error("Error on initialization");
}
}
+
+ public String toString() {
+ return table.toString();
+ }
public IoTString put(IoTString key, IoTString value) {
- while(true) {
- KeyValue oldvalue=table.get(key);
- if (tryput(key, value, false)) {
- return oldvalue.getValue();
- }
- }
- }
-
- private boolean tryput(IoTString key, IoTString value, boolean forcedresize) {
- Slot s=new Slot(sequencenumber+1, localmachineid, buffer.getSlot(sequencenumber).getHMAC());
- long seqn = buffer.getOldestSeqNum();
-
- if (forcedresize) {
- TableStatus status=new TableStatus(s, FORCED_RESIZE_INCREMENT + numslots);
+ while(true) {
+ KeyValue oldvalue=table.get(key);
+ if (tryput(key, value, false)) {
+ if (oldvalue==null)
+ return null;
+ else
+ return oldvalue.getValue();
+ }
+ }
+ }
+
+ void decrementLiveCount() {
+ liveslotcount--;
+ }
+
+ private void setResizeThreshold() {
+ int resize_lower=(int) (RESIZE_THRESHOLD * numslots);
+ resizethreshold=resize_lower-1+random.nextInt(numslots-resize_lower);
+ }
+
+ private boolean tryput(IoTString key, IoTString value, boolean resize) {
+ Slot s=new Slot(this, sequencenumber+1, localmachineid, buffer.getSlot(sequencenumber).getHMAC());
+ int newsize = 0;
+ if (liveslotcount > resizethreshold) {
+ resize=true;
+ newsize = (int) (numslots * RESIZE_MULTIPLE);
+ }
+
+ if (resize) {
+ newsize = (int) (numslots * RESIZE_MULTIPLE);
+ TableStatus status=new TableStatus(s, newsize);
s.addEntry(status);
}
+
+ if (!rejectedmessagelist.isEmpty()) {
+ long old_seqn=rejectedmessagelist.firstElement();
+ if (rejectedmessagelist.size() > REJECTED_THRESHOLD) {
+ long new_seqn=rejectedmessagelist.lastElement();
+ RejectedMessage rm=new RejectedMessage(s, localmachineid, old_seqn, new_seqn, false);
+ s.addEntry(rm);
+ } else {
+ long prev_seqn=-1;
+ int i=0;
+ /* Go through list of missing messages */
+ for(;i<rejectedmessagelist.size();i++) {
+ long curr_seqn=rejectedmessagelist.get(i);
+ Slot s_msg=buffer.getSlot(curr_seqn);
+ if (s_msg!=null)
+ break;
+ prev_seqn=curr_seqn;
+ }
+ /* Generate rejected message entry for missing messages */
+ if (prev_seqn != -1) {
+ RejectedMessage rm=new RejectedMessage(s, localmachineid, old_seqn, prev_seqn, false);
+ s.addEntry(rm);
+ }
+ /* Generate rejected message entries for present messages */
+ for(;i<rejectedmessagelist.size();i++) {
+ long curr_seqn=rejectedmessagelist.get(i);
+ Slot s_msg=buffer.getSlot(curr_seqn);
+ long machineid=s_msg.getMachineID();
+ RejectedMessage rm=new RejectedMessage(s, machineid, curr_seqn, curr_seqn, true);
+ s.addEntry(rm);
+ }
+ }
+ }
+
+ long newestseqnum = buffer.getNewestSeqNum();
+ long oldestseqnum = buffer.getOldestSeqNum();
+ if (lastliveslotseqn < oldestseqnum)
+ lastliveslotseqn = oldestseqnum;
+
+ long seqn = lastliveslotseqn;
+ boolean seenliveslot = false;
+ long firstiffull = newestseqnum + 1 - numslots;
+ long threshold = firstiffull + FREE_SLOTS;
- if ((numslots - buffer.size()) < FREE_SLOTS) {
- //have to check whether we have enough free slots
- seqn = buffer.getNewestSeqNum() + 1 - numslots;
- for(int i=0; i < FREE_SLOTS; i++, seqn++) {
- Slot prevslot=buffer.getSlot(seqn);
- if (!prevslot.isLive())
- continue;
- Vector<Entry> liveentries = prevslot.getLiveEntries();
- for(Entry liveentry:liveentries) {
- if (s.hasSpace(liveentry))
- s.addEntry(liveentry);
- else if (i==0) {
- if (s.canFit(liveentry))
- s.addEntry(liveentry);
- else if (!forcedresize) {
- return tryput(key, value, true);
- }
+ for(; seqn < threshold; seqn++) {
+ Slot prevslot=buffer.getSlot(seqn);
+ //Push slot number forward
+ if (!seenliveslot)
+ lastliveslotseqn = seqn;
+
+ if (!prevslot.isLive())
+ continue;
+ seenliveslot = true;
+ Vector<Entry> liveentries = prevslot.getLiveEntries(resize);
+ for(Entry liveentry:liveentries) {
+ if (s.hasSpace(liveentry)) {
+ s.addEntry(liveentry);
+ } else if (seqn==firstiffull) {
+ if (!resize) {
+ System.out.print("B");
+ return tryput(key, value, true);
}
- }
- }
- }
- KeyValue kv=new KeyValue(s, key, value);
- boolean insertedkv=false;
- if (s.hasSpace(kv)) {
- s.addEntry(kv);
- insertedkv=true;
- }
-
- long newestseqnum=buffer.getNewestSeqNum();
- search:
- for(;seqn<=newestseqnum;seqn++) {
- Slot prevslot=buffer.getSlot(seqn);
- if (!prevslot.isLive())
- continue;
- Vector<Entry> liveentries = prevslot.getLiveEntries();
- for(Entry liveentry:liveentries) {
- if (s.hasSpace(liveentry))
- s.addEntry(liveentry);
- else
- break search;
- }
- }
-
- int max=0;
- if (forcedresize)
- max = numslots + FORCED_RESIZE_INCREMENT;
- Slot[] array=cloud.putSlot(s, max);
- if (array == null)
- array = new Slot[] {s};
- else
- insertedkv=false;
-
- validateandupdate(array); // update data structure
-
- return insertedkv;
+ }
+ }
+ }
+
+ KeyValue kv=new KeyValue(s, key, value);
+ boolean insertedkv=false;
+ if (s.hasSpace(kv)) {
+ s.addEntry(kv);
+ insertedkv=true;
+ }
+
+ int skipcount=0;
+ search:
+ for(; seqn <= newestseqnum; seqn++) {
+ Slot prevslot=buffer.getSlot(seqn);
+ //Push slot number forward
+ if (!seenliveslot)
+ lastliveslotseqn = seqn;
+
+ if (!prevslot.isLive())
+ continue;
+ seenliveslot = true;
+ Vector<Entry> liveentries = prevslot.getLiveEntries(resize);
+ for(Entry liveentry:liveentries) {
+ if (s.hasSpace(liveentry))
+ s.addEntry(liveentry);
+ else {
+ skipcount++;
+ if (skipcount > SKIP_THRESHOLD)
+ break search;
+ }
+ }
+ }
+
+ int max=0;
+ if (resize)
+ max = newsize;
+ Slot[] array=cloud.putSlot(s, max);
+ if (array == null) {
+ array = new Slot[] {s};
+ rejectedmessagelist.clear();
+ } else {
+ if (array.length == 0)
+ throw new Error("Server Error: Did not send any slots");
+ rejectedmessagelist.add(s.getSequenceNumber());
+ insertedkv=false;
+ }
+
+ /* update data structure */
+ validateandupdate(array, true);
+
+ return insertedkv;
}
- private void validateandupdate(Slot[] newslots) {
- //The cloud communication layer has checked slot HMACs already
- //before decoding
+ private void validateandupdate(Slot[] newslots, boolean acceptupdatestolocal) {
+ /* The cloud communication layer has checked slot HMACs already
+ before decoding */
if (newslots.length==0)
return;
long firstseqnum=newslots[0].getSequenceNumber();
- if (firstseqnum < sequencenumber)
+ if (firstseqnum <= sequencenumber)
throw new Error("Server Error: Sent older slots!");
SlotIndexer indexer = new SlotIndexer(newslots, buffer);
checkHMACChain(indexer, newslots);
- initExpectedSize();
- for(Slot slot: newslots) {
- updateExpectedSize();
- processSlot(indexer, slot);
+ HashSet<Long> machineSet=new HashSet<Long>(lastmessagetable.keySet());
+
+ initExpectedSize(firstseqnum);
+ for(Slot slot: newslots) {
+ processSlot(indexer, slot, acceptupdatestolocal, machineSet);
+ updateExpectedSize();
+ }
+
+ /* If there is a gap, check to see if the server sent us everything. */
+ if (firstseqnum != (sequencenumber+1)) {
+ checkNumSlots(newslots.length);
+ if (!machineSet.isEmpty())
+ throw new Error("Missing record for machines: "+machineSet);
}
- checkNumSlots(newslots.length);
- commitNewMaxSize();
- //commit new to slots
- for(Slot slot:newslots) {
- buffer.putSlot(slot);
- }
+ commitNewMaxSize();
+
+ /* Commit new to slots. */
+ for(Slot slot:newslots) {
+ buffer.putSlot(slot);
+ liveslotcount++;
+ }
+ sequencenumber = newslots[newslots.length - 1].getSequenceNumber();
+ }
+
+ private int expectedsize, currmaxsize;
+
+ private void checkNumSlots(int numslots) {
+ if (numslots != expectedsize)
+ throw new Error("Server Error: Server did not send all slots. Expected: "+expectedsize+" Received:"+numslots);
+ }
+
+ private void initExpectedSize(long firstsequencenumber) {
+ long prevslots = firstsequencenumber;
+ expectedsize = (prevslots < ((long) numslots))?(int) prevslots:numslots;
+ currmaxsize = numslots;
+ }
+
+ private void updateExpectedSize() {
+ expectedsize++;
+ if (expectedsize > currmaxsize)
+ expectedsize = currmaxsize;
+ }
+
+ private void updateCurrMaxSize(int newmaxsize) {
+ currmaxsize=newmaxsize;
+ }
+
+ private void commitNewMaxSize() {
+ if (numslots != currmaxsize)
+ buffer.resize(currmaxsize);
+
+ numslots=currmaxsize;
+ setResizeThreshold();
}
- private int expectedsize, currmaxsize;
-
- private void checkNumSlots(int numslots) {
- if (numslots != expectedsize)
- throw new Error("Server Error: Server did not send all slots");
- }
-
- private void initExpectedSize() {
- expectedsize = (sequencenumber < ((long) numslots)) ? (int) sequencenumber : numslots;
- currmaxsize = numslots;
- }
-
- private void updateExpectedSize() {
- expectedsize++;
- if (expectedsize > currmaxsize)
- expectedsize = currmaxsize;
- }
-
- private void updateCurrMaxSize(int newmaxsize) {
- currmaxsize=newmaxsize;
- }
-
- private void commitNewMaxSize() {
- if (numslots != currmaxsize)
- buffer.resize(currmaxsize);
-
- numslots=currmaxsize;
- }
-
private void processEntry(KeyValue entry, SlotIndexer indexer) {
IoTString key=entry.getKey();
KeyValue oldvalue=table.get(key);
table.put(key, entry);
}
- private void processEntry(LastMessage entry, SlotIndexer indexer) {
- updateLastMessage(entry.getMachineID(), entry.getSequenceNumber(), entry);
+ private void processEntry(LastMessage entry, SlotIndexer indexer, HashSet<Long> machineSet) {
+ updateLastMessage(entry.getMachineID(), entry.getSequenceNumber(), entry, false, machineSet);
}
private void processEntry(RejectedMessage entry, SlotIndexer indexer) {
}
}
}
+
+ HashSet<Long> watchset=new HashSet<Long>();
+ for(Map.Entry<Long, Pair<Long,Liveness> > lastmsg_entry:lastmessagetable.entrySet()) {
+ long entry_mid=lastmsg_entry.getKey();
+ /* We've seen it, don't need to continue to watch. Our next
+ * message will implicitly acknowledge it. */
+ if (entry_mid == localmachineid)
+ continue;
+ Pair<Long, Liveness> v=lastmsg_entry.getValue();
+ long entry_seqn=v.getFirst();
+ if (entry_seqn < newseqnum) {
+ addWatchList(entry_mid, entry);
+ watchset.add(entry_mid);
+ }
+ }
+ if (watchset.isEmpty())
+ entry.setDead();
+ else
+ entry.setWatchSet(watchset);
+ }
+
+ private void addWatchList(long machineid, RejectedMessage entry) {
+ HashSet<RejectedMessage> entries=watchlist.get(machineid);
+ if (entries == null)
+ watchlist.put(machineid, entries=new HashSet<RejectedMessage>());
+ entries.add(entry);
}
private void processEntry(TableStatus entry, SlotIndexer indexer) {
- int newnumslots=entry.getMaxSlots();
- updateCurrMaxSize(newnumslots);
- if (lastTableStatus != null)
- lastTableStatus.setDead();
- lastTableStatus = entry;
+ int newnumslots=entry.getMaxSlots();
+ updateCurrMaxSize(newnumslots);
+ if (lastTableStatus != null)
+ lastTableStatus.setDead();
+ lastTableStatus = entry;
}
- private void updateLastMessage(long machineid, long seqnum, Liveness liveness) {
+ private void updateLastMessage(long machineid, long seqnum, Liveness liveness, boolean acceptupdatestolocal, HashSet<Long> machineSet) {
+ machineSet.remove(machineid);
+
+ HashSet<RejectedMessage> watchset=watchlist.get(machineid);
+ if (watchset != null) {
+ for(Iterator<RejectedMessage> rmit=watchset.iterator(); rmit.hasNext(); ) {
+ RejectedMessage rm=rmit.next();
+ if (rm.getNewSeqNum() <= seqnum) {
+ /* Remove it from our watchlist */
+ rmit.remove();
+ /* Decrement machines that need to see this notification */
+ rm.removeWatcher(machineid);
+ }
+ }
+ }
+
+ if (machineid == localmachineid) {
+ /* Our own messages are immediately dead. */
+ if (liveness instanceof LastMessage) {
+ ((LastMessage)liveness).setDead();
+ } else if (liveness instanceof Slot) {
+ ((Slot)liveness).setDead();
+ } else {
+ throw new Error("Unrecognized type");
+ }
+ }
+
+
Pair<Long, Liveness> lastmsgentry = lastmessagetable.put(machineid, new Pair<Long, Liveness>(seqnum, liveness));
if (lastmsgentry == null)
return;
long lastmsgseqnum = lastmsgentry.getFirst();
Liveness lastentry = lastmsgentry.getSecond();
- if (lastentry instanceof LastMessage) {
- ((LastMessage)lastentry).setDead();
- } else if (lastentry instanceof Slot) {
- ((Slot)lastentry).setDead();
- } else {
- throw new Error("Unrecognized type");
+ if (machineid != localmachineid) {
+ if (lastentry instanceof LastMessage) {
+ ((LastMessage)lastentry).setDead();
+ } else if (lastentry instanceof Slot) {
+ ((Slot)lastentry).setDead();
+ } else {
+ throw new Error("Unrecognized type");
+ }
}
-
+
if (machineid == localmachineid) {
- if (lastmsgseqnum != seqnum)
+ if (lastmsgseqnum != seqnum && !acceptupdatestolocal)
throw new Error("Server Error: Mismatch on local machine sequence number");
} else {
if (lastmsgseqnum > seqnum)
}
}
- private void processSlot(SlotIndexer indexer, Slot slot) {
- updateLastMessage(slot.getMachineID(), slot.getSequenceNumber(), slot);
-
+ private void processSlot(SlotIndexer indexer, Slot slot, boolean acceptupdatestolocal, HashSet<Long> machineSet) {
+ updateLastMessage(slot.getMachineID(), slot.getSequenceNumber(), slot, acceptupdatestolocal, machineSet);
for(Entry entry : slot.getEntries()) {
switch(entry.getType()) {
case Entry.TypeKeyValue:
break;
case Entry.TypeLastMessage:
- processEntry((LastMessage)entry, indexer);
+ processEntry((LastMessage)entry, indexer, machineSet);
break;
case Entry.TypeRejectedMessage:
Slot prevslot=indexer.getSlot(currslot.getSequenceNumber()-1);
if (prevslot != null &&
!Arrays.equals(prevslot.getHMAC(), currslot.getPrevHMAC()))
- throw new Error("Server Error: Invalid HMAC Chain");
+ throw new Error("Server Error: Invalid HMAC Chain"+currslot+" "+prevslot);
}
}
}
projects / iotcloud.git / blobdiff