diff --git a/src/main/java/com/github/emboss/siphash/SipHash.java b/src/main/java/com/github/emboss/siphash/SipHash.java
index c0f48c3..228f27c 100644
--- a/src/main/java/com/github/emboss/siphash/SipHash.java
+++ b/src/main/java/com/github/emboss/siphash/SipHash.java
@@ -27,19 +27,19 @@ private static long lastBlock(byte[] data, int iter) {
 
         switch (data.length % 8) {
             case 7: 
-                last |= ((long) data[off + 6]) << 48;
+                last |= (((long) data[off + 6]) & 0xff) << 48;
             case 6:
-                last |= ((long) data[off + 5]) << 40;
+                last |= (((long) data[off + 5]) & 0xff) << 40;
             case 5:
-                last |= ((long) data[off + 4]) << 32;
+                last |= (((long) data[off + 4]) & 0xff) << 32;
             case 4:
-                last |= ((long) data[off + 3]) << 24;
+                last |= (((long) data[off + 3]) & 0xff) << 24;
             case 3:
-                last |= ((long) data[off + 2]) << 16;
+                last |= (((long) data[off + 2]) & 0xff) << 16;
             case 2:
-                last |= ((long) data[off + 1]) << 8;
+                last |= (((long) data[off + 1]) & 0xff) << 8;
             case 1:
-                last |= (long) data[off];
+                last |= ((long) data[off]) & 0xff;
                 break;
             case 0:
                 break;
diff --git a/src/main/java/com/github/emboss/siphash/UnsignedInt64.java b/src/main/java/com/github/emboss/siphash/UnsignedInt64.java
index afc296f..4d3269d 100644
--- a/src/main/java/com/github/emboss/siphash/UnsignedInt64.java
+++ b/src/main/java/com/github/emboss/siphash/UnsignedInt64.java
@@ -12,14 +12,14 @@ public static long binToInt(byte[] b) {
     }
     
     public static long binToIntOffset(byte[] b, int off) {
-        return ((long) b[off    ])       |
-               ((long) b[off + 1]) << 8  |
-               ((long) b[off + 2]) << 16 |
-               ((long) b[off + 3]) << 24 |
-               ((long) b[off + 4]) << 32 |
-               ((long) b[off + 5]) << 40 |
-               ((long) b[off + 6]) << 48 |
-               ((long) b[off + 7]) << 56;
+        return (((long) b[off    ]) & 0xff)     |
+               (((long) b[off + 1]) & 0xff) << 8  |
+               (((long) b[off + 2]) & 0xff) << 16 |
+               (((long) b[off + 3]) & 0xff) << 24 |
+               (((long) b[off + 4]) & 0xff) << 32 |
+               (((long) b[off + 5]) & 0xff) << 40 |
+               (((long) b[off + 6]) & 0xff) << 48 |
+               (((long) b[off + 7]) & 0xff) << 56;
     }
     
     public static void intToBin(long l, byte[] b) {