fix: checksum format (#1178)

Fix checksum format to match the server's format -- unsigned long.

Author: nimf

datastore-v1-proto-client/src/main/java/com/google/datastore/v1/client/ChecksumEnforcingInputStream.java

@@ -76,7 +76,7 @@ public int read(byte[] b, int off, int len) throws IOException {
  endToEndChecksumHandler.update(b, off, i);
  } else {
  // no more payload to read. compute checksum and verify
- if (!expectedChecksum.equalsIgnoreCase(endToEndChecksumHandler.hash())) {
+ if (!expectedChecksum.equals(endToEndChecksumHandler.hash())) {
  throw new IOException("possible memory corruption on payload detected");
  }
  }

datastore-v1-proto-client/src/main/java/com/google/datastore/v1/client/EndToEndChecksumHandler.java

@@ -40,7 +40,11 @@ static String computeChecksum(byte[] bytes) {
  return null;
  }
  HashCode hc = getNewCrc32cHasher().putBytes(bytes).hash();
- return hc.toString();
+ return hashToString(hc);
+ }
+
+ private static String hashToString(HashCode hc) {
+ return String.valueOf(Integer.toUnsignedLong(hc.asInt()));
  }
 
  private static Hasher getNewCrc32cHasher() {
@@ -59,7 +63,7 @@ static boolean validateChecksum(String checksum, byte[] bytes) {
  && !checksum.isEmpty()
  && bytes != null
  && bytes.length > 0
- && checksum.equalsIgnoreCase(computeChecksum(bytes));
+ && checksum.equals(computeChecksum(bytes));
  }
 
  static boolean hasChecksumHeader(HttpResponse response) {
@@ -76,6 +80,6 @@ void update(byte[] bytes, int off, int len) {
  }
 
  String hash() {
- return hasher.hash().toString();
+ return hashToString(hasher.hash());
  }
 }

datastore-v1-proto-client/src/test/java/com/google/datastore/v1/client/EndToEndChecksumHandlerTest.java

@@ -16,6 +16,7 @@
 package com.google.datastore.v1.client;
 
 import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
@@ -27,14 +28,23 @@
 /** Test for {@link EndToEndChecksumHandler}. */
 @RunWith(JUnit4.class)
 public class EndToEndChecksumHandlerTest {
- private byte[] payloadBytes = "This is a long string with numbers 1234, 134.56 ".getBytes(UTF_8);
+ private final byte[] payloadBytes =
+ "This is a long string with numbers 1234, 134.56 ".getBytes(UTF_8);
+ private final byte[] payloadForUnsignedLongChecksum = "aaa".getBytes(UTF_8);
+ private final String unsignedLongChecksum = "3818383321";
 
  @Test
  public void validateChecksum_correctChecksum() {
  String computed = EndToEndChecksumHandler.computeChecksum(payloadBytes);
  assertTrue(EndToEndChecksumHandler.validateChecksum(computed, payloadBytes));
  }
 
+ @Test
+ public void computeChecksum_returnsUnsignedLongAsStringValue() {
+ String computed = EndToEndChecksumHandler.computeChecksum(payloadForUnsignedLongChecksum);
+ assertEquals("computeChecksum return value", unsignedLongChecksum, computed);
+ }
+
  @Test
  public void validateChecksum_incorrectChecksum() {
  String computed = EndToEndChecksumHandler.computeChecksum("random string".getBytes(UTF_8));

datastore-v1-proto-client/src/test/java/com/google/datastore/v1/client/RemoteRpcTest.java

@@ -176,7 +176,7 @@ public void testHttpHeaders_expectE2eChecksumHeader() throws IOException {
  httpRequest
  .getHeaders()
  .getFirstHeaderStringValue(EndToEndChecksumHandler.HTTP_REQUEST_CHECKSUM_HEADER);
- assertEquals(8, header.length());
+ assertEquals(9, header.length());
  }
 
  @Test