Merge branch 'ri-size' into 'master'

Router: Enforce consistent max RI size

See merge request i2p-hackers/i2p.i2p!168

router/java/src/net/i2p/data/i2np/DatabaseStoreMessage.java

@@ -185,6 +185,8 @@ public class DatabaseStoreMessage extends FastI2NPMessageImpl {
                 // If we do delay it, getEntry() will have to check if _dbEntry is null and _byteCache
                 // is non-null, and then decompress.
                 byte decompressed[] = DataHelper.decompress(data, curIndex, compressedSize);
+                if (decompressed.length > RouterInfo.MAX_UNCOMPRESSED_SIZE)
+                    throw new I2NPMessageException("RI too big: " + decompressed.length);
                 _dbEntry.readBytes(new ByteArrayInputStream(decompressed));
             } catch (DataFormatException dfe) {
                 throw new I2NPMessageException("Error reading the routerInfo", dfe);

router/java/src/net/i2p/data/router/RouterInfo.java

@@ -87,6 +87,15 @@ public class RouterInfo extends DatabaseEntry {
     public static final char CAPABILITY_HIDDEN = 'H';
     private static final int MAX_ADDRESSES = 16;
 
+    /**
+     *  All legit RIs are currently under 2KB.
+     *  May need to be adjusted if we add a huge new enctype or sigtype.
+     *  Enforced in DatabaseStoreMessage, the transports, and reseed.
+     *
+     *  @since 0.9.62
+     */
+    public static final int MAX_UNCOMPRESSED_SIZE = 4*1024;
+
     /** Public string of chars which serve as bandwidth capacity markers
      * NOTE: individual chars defined in Router.java
      */

router/java/src/net/i2p/router/networkdb/kademlia/PersistentDataStore.java

@@ -541,6 +541,12 @@ public class PersistentDataStore extends TransientDataStore {
          *  @since 0.9.58
          */
         public boolean read() {
+            if (_routerFile.length() > RouterInfo.MAX_UNCOMPRESSED_SIZE) {
+                if (_log.shouldWarn())
+                    _log.warn("RI file too big " + _routerFile.length() + ": " + _routerFile);
+                _routerFile.delete();
+                return false;
+            }
             if (!shouldRead()) return false;
             if (_log.shouldLog(Log.DEBUG))
                 _log.debug("Reading " + _routerFile);

router/java/src/net/i2p/router/networkdb/reseed/Reseeder.java

@@ -24,6 +24,7 @@ import net.i2p.crypto.SU3File;
 import net.i2p.data.Base64;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Hash;
+import net.i2p.data.router.RouterInfo;
 import net.i2p.router.RouterClock;
 import net.i2p.router.RouterContext;
 import net.i2p.router.util.EventLog;
@@ -911,7 +912,7 @@ public class Reseeder {
                     String name = f.getName();
                     if (name.length() != ROUTERINFO_PREFIX.length() + 44 + ROUTERINFO_SUFFIX.length() ||
                         name.equals(ourB64) ||
-                        f.length() > 10*1024 ||
+                        f.length() > RouterInfo.MAX_UNCOMPRESSED_SIZE ||
                         f.lastModified() < minTime ||
                         !name.startsWith(ROUTERINFO_PREFIX) ||
                         !name.endsWith(ROUTERINFO_SUFFIX) ||

router/java/src/net/i2p/router/transport/ntcp/NTCP2Payload.java

@@ -117,10 +117,12 @@ class NTCP2Payload {
 
                 case BLOCK_ROUTERINFO:
                     int flag = payload[i] & 0xff;
+                    if (len - 1 > RouterInfo.MAX_UNCOMPRESSED_SIZE)
+                        throw new DataFormatException("RI too big: " + (len - 1));
                     RouterInfo alice = new RouterInfo();
                     ByteArrayInputStream bais = new ByteArrayInputStream(payload, i + 1, len - 1);
                     alice.readBytes(bais, true);
-                    cb.gotRI(alice, isHandshake, (flag & 0x01) != 0 && len < 4*1024);
+                    cb.gotRI(alice, isHandshake, (flag & 0x01) != 0 && len < 3*1024);
                     break;
 
                 case BLOCK_I2NP:

router/java/src/net/i2p/router/transport/udp/SSU2Payload.java

@@ -197,16 +197,20 @@ class SSU2Payload {
                     if (ftot == 0)
                         throw new IOException("Bad fragment count for ROUTERINFO: " + ftot);
                     if (fnum == 0 && ftot == 1) {
-                        RouterInfo alice = new RouterInfo();
                         ByteArrayInputStream bais;
                         if (gz) {
                             byte decompressed[] = DataHelper.decompress(payload, i + 2, len - 2);
+                            if (decompressed.length > RouterInfo.MAX_UNCOMPRESSED_SIZE)
+                                throw new DataFormatException("RI too big: " + decompressed.length);
                             bais = new ByteArrayInputStream(decompressed);
                         } else {
+                            if (len - 2 > RouterInfo.MAX_UNCOMPRESSED_SIZE)
+                                throw new DataFormatException("RI too big: " + (len - 2));
                             bais = new ByteArrayInputStream(payload, i + 2, len - 2);
                         }
-                        if (bais.available() >= 4*1024)
+                        if (bais.available() >= 3*1024)
                             flood = false;
+                        RouterInfo alice = new RouterInfo();
                         alice.readBytes(bais, true);
                         cb.gotRI(alice, isHandshake, flood);
                     } else {