Introduced exception handling for wrong payload sizes (in StreamDeser…

…ializationContext) and wrong URIs (in PendingAttestation). Fixed broken test in TestUnknownAttestation, detailed tests for wrong URIs in TestPendingAttestation. Added new exceptions to all methods in source or tests where exceptions can occur.

src/main/java/com/eternitywall/ots/Calendar.java

@@ -3,6 +3,7 @@
 import com.eternitywall.http.Request;
 import com.eternitywall.http.Response;
 import com.eternitywall.ots.exceptions.CommitmentNotFoundException;
+import com.eternitywall.ots.exceptions.DeserializationException;
 import com.eternitywall.ots.exceptions.ExceededSizeException;
 import com.eternitywall.ots.exceptions.UrlException;
 import org.bitcoinj.core.ECKey;
@@ -63,7 +64,7 @@ public String getUrl() {
      *
      * @param digest The digest hash to send.
      * @return the Timestamp received from the calendar.
-     * @throws ExceededSizeException if response is too big.
+     * @throws DeserializationException if response is too big.
      * @throws UrlException          if url is not reachable.
      */
     public Timestamp submit(byte[] digest) throws ExceededSizeException, UrlException {
@@ -100,11 +101,11 @@ public Timestamp submit(byte[] digest) throws ExceededSizeException, UrlExceptio
      *
      * @param commitment The digest hash to send.
      * @return the Timestamp from the calendar server (with blockchain information if already written).
-     * @throws ExceededSizeException       if response is too big.
+     * @throws DeserializationException       if response is too big.
      * @throws UrlException                if url is not reachable.
      * @throws CommitmentNotFoundException if commit is not found.
      */
-    public Timestamp getTimestamp(byte[] commitment) throws ExceededSizeException, CommitmentNotFoundException, UrlException {
+    public Timestamp getTimestamp(byte[] commitment) throws DeserializationException, CommitmentNotFoundException, UrlException {
         try {
             Map<String, String> headers = new HashMap<>();
             headers.put("Accept", "application/vnd.opentimestamps.v1");
@@ -117,7 +118,7 @@ public Timestamp getTimestamp(byte[] commitment) throws ExceededSizeException, C
             Response response = task.call();
             byte[] body = response.getBytes();
             if (body.length > 10000) {
-                throw new ExceededSizeException("Calendar response exceeded size limit");
+                throw new DeserializationException("Calendar response exceeded size limit");
             }
 
             if (!response.isOk()) {

src/main/java/com/eternitywall/ots/DetachedTimestampFile.java

@@ -1,5 +1,6 @@
 package com.eternitywall.ots;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import com.eternitywall.ots.op.Op;
 import com.eternitywall.ots.op.OpCrypto;
 import com.eternitywall.ots.op.OpSHA256;
@@ -96,7 +97,7 @@ public byte[] serialize() {
      * @param ctx The stream deserialization context.
      * @return The generated com.eternitywall.ots.DetachedTimestampFile object.
      */
-    public static DetachedTimestampFile deserialize(StreamDeserializationContext ctx) {
+    public static DetachedTimestampFile deserialize(StreamDeserializationContext ctx) throws DeserializationException {
         ctx.assertMagic(HEADER_MAGIC);
         ctx.readVaruint();
 
@@ -115,7 +116,7 @@ public static DetachedTimestampFile deserialize(StreamDeserializationContext ctx
      * @param ots The byte array of deserialization DetachedFileTimestamped.
      * @return The generated com.eternitywall.ots.DetachedTimestampFile object.
      */
-    public static DetachedTimestampFile deserialize(byte[] ots) {
+    public static DetachedTimestampFile deserialize(byte[] ots) throws DeserializationException {
         StreamDeserializationContext ctx = new StreamDeserializationContext(ots);
 
         return DetachedTimestampFile.deserialize(ctx);

src/main/java/com/eternitywall/ots/OtsCli.java

@@ -3,6 +3,7 @@
 import com.eternitywall.ots.attestation.BitcoinBlockHeaderAttestation;
 import com.eternitywall.ots.attestation.EthereumBlockHeaderAttestation;
 import com.eternitywall.ots.attestation.LitecoinBlockHeaderAttestation;
+import com.eternitywall.ots.exceptions.DeserializationException;
 import com.eternitywall.ots.op.OpSHA256;
 import org.apache.commons.cli.BasicParser;
 import org.apache.commons.cli.CommandLine;
@@ -216,6 +217,8 @@ public static void info(String argsOts, boolean verbose) {
             System.out.println(infoResult);
         } catch (IOException e) {
             log.severe("No valid file");
+        } catch (DeserializationException e) {
+            log.severe("Deserialization error: size was either too long or short");
         }
     }
 

src/main/java/com/eternitywall/ots/StreamDeserializationContext.java

@@ -1,5 +1,6 @@
 package com.eternitywall.ots;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.Arrays;
 import java.util.logging.Logger;
 
@@ -65,27 +66,29 @@ public int readVaruint() {
         return value;
     }
 
-    public byte[] readBytes(int expectedLength) {
+    public byte[] readBytes(int expectedLength) throws DeserializationException {
+
+
         if (expectedLength == 0) {
             return this.readVarbytes(1024, 0);
         }
 
         return this.read(expectedLength);
     }
 
-    public byte[] readVarbytes(int maxLen) {
+    public byte[] readVarbytes(int maxLen) throws DeserializationException {
         return readVarbytes(maxLen, 0);
     }
 
-    public byte[] readVarbytes(int maxLen, int minLen) {
+    public byte[] readVarbytes(int maxLen, int minLen) throws DeserializationException {
         int l = this.readVaruint();
 
-        if ((l & 0xff) > maxLen) {
+        if (l  > maxLen) {
             log.severe("varbytes max length exceeded;");
-            return null;
-        } else if ((l & 0xff) < minLen) {
+            throw new DeserializationException("varbytes max length exceeded;");
+        } else if (l < minLen) {
             log.severe("varbytes min length not met;");
-            return null;
+            throw new DeserializationException("varbytes min length not met;");
         }
 
         return this.read(l);

src/main/java/com/eternitywall/ots/Timestamp.java

@@ -2,6 +2,7 @@
 
 import com.eternitywall.ots.attestation.BitcoinBlockHeaderAttestation;
 import com.eternitywall.ots.attestation.TimeAttestation;
+import com.eternitywall.ots.exceptions.DeserializationException;
 import com.eternitywall.ots.op.Op;
 import com.eternitywall.ots.op.OpBinary;
 import com.eternitywall.ots.op.OpSHA256;
@@ -44,7 +45,7 @@ public Timestamp(byte[] msg) {
      * @param initialMsg - The initial message.
      * @return The deserialized Timestamp.
      */
-    public static Timestamp deserialize(byte[] ots, byte[] initialMsg) {
+    public static Timestamp deserialize(byte[] ots, byte[] initialMsg) throws DeserializationException {
         StreamDeserializationContext ctx = new StreamDeserializationContext(ots);
 
         return Timestamp.deserialize(ctx, initialMsg);
@@ -63,7 +64,8 @@ public static Timestamp deserialize(byte[] ots, byte[] initialMsg) {
      * @param initialMsg - The initial message.
      * @return The deserialized Timestamp.
      */
-    public static Timestamp deserialize(StreamDeserializationContext ctx, byte[] initialMsg) {
+    public static Timestamp deserialize(StreamDeserializationContext ctx, byte[] initialMsg)
+        throws DeserializationException {
         Timestamp self = new Timestamp(initialMsg);
         byte tag = ctx.readBytes(1)[0];
 
@@ -78,7 +80,8 @@ public static Timestamp deserialize(StreamDeserializationContext ctx, byte[] ini
         return self;
     }
 
-    private static void doTagOrAttestation(Timestamp self, StreamDeserializationContext ctx, byte tag, byte[] initialMsg) {
+    private static void doTagOrAttestation(Timestamp self, StreamDeserializationContext ctx, byte tag, byte[] initialMsg)
+        throws DeserializationException {
         if ((tag & 0xff) == 0x00) {
             TimeAttestation attestation = TimeAttestation.deserialize(ctx);
             self.attestations.add(attestation);

src/main/java/com/eternitywall/ots/attestation/PendingAttestation.java

@@ -4,6 +4,7 @@
 import com.eternitywall.ots.StreamSerializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.logging.Logger;
@@ -74,13 +75,20 @@ public static boolean checkUri(byte[] uri) {
         return true;
     }
 
-    public static PendingAttestation deserialize(StreamDeserializationContext ctxPayload) {
-        byte[] utf8Uri = ctxPayload.readVarbytes(PendingAttestation._MAX_URI_LENGTH);
+    public static PendingAttestation deserialize(StreamDeserializationContext ctxPayload)
+        throws DeserializationException {
+
+        byte[] utf8Uri;
+        try {
+            utf8Uri = ctxPayload.readVarbytes(PendingAttestation._MAX_URI_LENGTH);
+        } catch (DeserializationException e) {
+            log.severe("URI too long and thus invalid: ");
+            throw new DeserializationException("Invalid URI: ");
+        }
 
         if (PendingAttestation.checkUri(utf8Uri) == false) {
             log.severe("Invalid URI: ");
-
-            return null;
+            throw new DeserializationException("Invalid URI: ");
         }
 
         return new PendingAttestation(utf8Uri);

src/main/java/com/eternitywall/ots/attestation/TimeAttestation.java

@@ -4,6 +4,7 @@
 import com.eternitywall.ots.StreamSerializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.Arrays;
 import java.util.logging.Logger;
 
@@ -30,7 +31,7 @@ public byte[] _TAG() {
      * @param ctx The stream deserialization context.
      * @return The specific subclass Attestation.
      */
-    public static TimeAttestation deserialize(StreamDeserializationContext ctx) {
+    public static TimeAttestation deserialize(StreamDeserializationContext ctx) throws DeserializationException {
         // console.log('attestation deserialize');
 
         byte[] tag = ctx.readBytes(_TAG_SIZE);

src/main/java/com/eternitywall/ots/attestation/UnknownAttestation.java

@@ -4,6 +4,7 @@
 import com.eternitywall.ots.StreamSerializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.Arrays;
 import java.util.logging.Logger;
 
@@ -36,7 +37,7 @@ public void serializePayload(StreamSerializationContext ctx) {
         ctx.writeBytes(this.payload);
     }
 
-    public static UnknownAttestation deserialize(StreamDeserializationContext ctxPayload, byte[] tag) {
+    public static UnknownAttestation deserialize(StreamDeserializationContext ctxPayload, byte[] tag) throws DeserializationException {
         byte[] payload = ctxPayload.readVarbytes(_MAX_PAYLOAD_SIZE);
 
         return new UnknownAttestation(tag, payload);

src/main/java/com/eternitywall/ots/exceptions/DeserializationException.java

@@ -0,0 +1,7 @@
+package com.eternitywall.ots.exceptions;
+
+public class DeserializationException extends Exception {
+    public DeserializationException(String message) {
+        super(message);
+    }
+}

src/main/java/com/eternitywall/ots/exceptions/ExceededSizeException.java

@@ -1,7 +1,7 @@
 package com.eternitywall.ots.exceptions;
 
 public class ExceededSizeException extends Exception {
-    public ExceededSizeException(String message) {
-        super(message);
-    }
+  public ExceededSizeException(String message) {
+    super(message);
+  }
 }

src/main/java/com/eternitywall/ots/op/Op.java

@@ -4,6 +4,7 @@
 import com.eternitywall.ots.StreamSerializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.logging.Logger;
 
 /**
@@ -61,7 +62,7 @@ public byte _TAG() {
      * @param ctx The stream deserialization context.
      * @return The subclass Operation.
      */
-    public static Op deserialize(StreamDeserializationContext ctx) {
+    public static Op deserialize(StreamDeserializationContext ctx) throws DeserializationException {
         byte tag = ctx.readBytes(1)[0];
 
         return Op.deserializeFromTag(ctx, tag);
@@ -74,7 +75,8 @@ public static Op deserialize(StreamDeserializationContext ctx) {
      * @param tag The tag of the operation.
      * @return The subclass Operation.
      */
-    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag) {
+    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag)
+        throws DeserializationException {
         if (tag == OpAppend._TAG) {
             return OpAppend.deserializeFromTag(ctx, tag);
         } else if (tag == OpPrepend._TAG) {

src/main/java/com/eternitywall/ots/op/OpAppend.java

@@ -3,6 +3,7 @@
 import com.eternitywall.ots.StreamDeserializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.Arrays;
 import java.util.logging.Logger;
 
@@ -44,7 +45,8 @@ public byte[] call(byte[] msg) {
         return Utils.arraysConcat(msg, this.arg);
     }
 
-    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag) {
+    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag)
+        throws DeserializationException {
         return OpBinary.deserializeFromTag(ctx, tag);
     }
 

src/main/java/com/eternitywall/ots/op/OpBinary.java

@@ -4,6 +4,7 @@
 import com.eternitywall.ots.StreamSerializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.Arrays;
 import java.util.logging.Logger;
 
@@ -33,7 +34,8 @@ public OpBinary(byte[] arg_) {
         this.arg = arg_;
     }
 
-    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag) {
+    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag)
+        throws DeserializationException {
         byte[] arg = ctx.readVarbytes(_MAX_RESULT_LENGTH, 1);
 
         if (tag == OpAppend._TAG) {

src/main/java/com/eternitywall/ots/op/OpPrepend.java

@@ -3,6 +3,7 @@
 import com.eternitywall.ots.StreamDeserializationContext;
 import com.eternitywall.ots.Utils;
 
+import com.eternitywall.ots.exceptions.DeserializationException;
 import java.util.Arrays;
 import java.util.logging.Logger;
 
@@ -44,7 +45,8 @@ public byte[] call(byte[] msg) {
         return Utils.arraysConcat(this.arg, msg);
     }
 
-    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag) {
+    public static Op deserializeFromTag(StreamDeserializationContext ctx, byte tag)
+        throws DeserializationException {
         return OpBinary.deserializeFromTag(ctx, tag);
     }
 

src/test/java/com/eternitywall/TestLongReceipt.java

@@ -3,6 +3,7 @@
 import com.eternitywall.ots.StreamDeserializationContext;
 import com.eternitywall.ots.StreamSerializationContext;
 import com.eternitywall.ots.Timestamp;
+import com.eternitywall.ots.exceptions.DeserializationException;
 import org.junit.Test;
 
 import javax.xml.bind.DatatypeConverter;
@@ -13,7 +14,7 @@
 
 public class TestLongReceipt {
     @Test
-    public void testException() {
+    public void testException() throws DeserializationException {
         String digest = "c858838f62f908c922f9cd734e49c8fa6ee9a3b8a77093ac0969cba429249412";
         byte[] digestByte = DatatypeConverter.parseHexBinary(digest);
         Timestamp root = new Timestamp(digestByte);

src/test/java/com/eternitywall/TestOpenTimestamps.java

@@ -11,6 +11,7 @@
 import com.eternitywall.ots.Utils;
 import com.eternitywall.ots.VerifyResult;
 import com.eternitywall.ots.attestation.TimeAttestation;
+import com.eternitywall.ots.exceptions.DeserializationException;
 import com.eternitywall.ots.exceptions.VerificationException;
 import com.eternitywall.ots.op.OpSHA256;
 import org.junit.After;
@@ -79,7 +80,7 @@ public void loadData() throws ExecutionException, InterruptedException, IOExcept
     }
 
     @Test
-    public void info() {
+    public void info() throws DeserializationException {
         String result1 = OpenTimestamps.info(DetachedTimestampFile.deserialize(incompleteOts));
         assertNotNull(result1);
         assertNotNull(incompleteOtsInfo);
@@ -157,7 +158,7 @@ public void verify2() throws Exception {
     }
 
     @Test
-    public void verify() throws NoSuchAlgorithmException, IOException {
+    public void verify() throws NoSuchAlgorithmException, IOException, DeserializationException {
         {
             DetachedTimestampFile detachedOts = DetachedTimestampFile.deserialize(helloWorldOts);
             DetachedTimestampFile detached = DetachedTimestampFile.from(Hash.from(helloWorld, OpSHA256._TAG));
@@ -226,7 +227,7 @@ public void upgrade() {
     }
 
     @Test
-    public void test() {
+    public void test() throws DeserializationException {
         byte[] ots = Utils.hexToBytes("F0105C3F2B3F8524A32854E07AD8ADDE9C1908F10458D95A36F008088D287213A8B9880083DFE30D2EF90C8E2C2B68747470733A2F2F626F622E6274632E63616C656E6461722E6F70656E74696D657374616D70732E6F7267");
         byte[] digest = Utils.hexToBytes("7aa9273d2a50dbe0cc5a6ccc444a5ca90c9491dd2ac91849e45195ae46f64fe352c3a63ba02775642c96131df39b5b85");