commons-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From bode...@apache.org
Subject svn commit: r1358504 - in /commons/proper/compress/trunk/src: main/java/org/apache/commons/compress/archivers/tar/ test/java/org/apache/commons/compress/archivers/tar/
Date Sat, 07 Jul 2012 05:19:39 GMT
Author: bodewig
Date: Sat Jul  7 05:19:39 2012
New Revision: 1358504

URL: http://svn.apache.org/viewvc?rev=1358504&view=rev
Log:
COMPRESS-191 add checksum check to TarArchiveEntry.  Submitted by Jukka Zitting.

Modified:
    commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarArchiveEntry.java
    commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarConstants.java
    commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarUtils.java
    commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveEntryTest.java
    commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveInputStreamTest.java
    commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarUtilsTest.java

Modified: commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarArchiveEntry.java
URL: http://svn.apache.org/viewvc/commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarArchiveEntry.java?rev=1358504&r1=1358503&r2=1358504&view=diff
==============================================================================
--- commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarArchiveEntry.java
(original)
+++ commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarArchiveEntry.java
Sat Jul  7 05:19:39 2012
@@ -132,6 +132,9 @@ public class TarArchiveEntry implements 
     /** The entry's modification time. */
     private long modTime;
 
+    /** If the header checksum is reasonably correct. */
+    private boolean checkSumOK;
+
     /** The entry's link flag. */
     private byte linkFlag;
 
@@ -551,6 +554,17 @@ public class TarArchiveEntry implements 
     }
 
     /**
+     * Get this entry's checksum status.
+     *
+     * @return if the header checksum is reasonably correct
+     * @see TarUtils#verifyCheckSum(byte[])
+     * @since 1.5
+     */
+    public boolean isCheckSumOK() {
+        return checkSumOK;
+    }
+
+    /**
      * Get this entry's file.
      *
      * @return This entry's file.
@@ -942,6 +956,7 @@ public class TarArchiveEntry implements 
         offset += SIZELEN;
         modTime = TarUtils.parseOctalOrBinary(header, offset, MODTIMELEN);
         offset += MODTIMELEN;
+        checkSumOK = TarUtils.verifyCheckSum(header);
         offset += CHKSUMLEN;
         linkFlag = header[offset++];
         linkName = oldStyle ? TarUtils.parseName(header, offset, NAMELEN)

Modified: commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarConstants.java
URL: http://svn.apache.org/viewvc/commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarConstants.java?rev=1358504&r1=1358503&r2=1358504&view=diff
==============================================================================
--- commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarConstants.java
(original)
+++ commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarConstants.java
Sat Jul  7 05:19:39 2012
@@ -69,6 +69,11 @@ public interface TarConstants {
     int    CHKSUMLEN = 8;
 
     /**
+     * Offset of the checksum field within header record.
+     */
+    int    CHKSUM_OFFSET = 148;
+
+    /**
      * The length of the size field in a header buffer.
      * Includes the trailing space or NUL.
      */

Modified: commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarUtils.java
URL: http://svn.apache.org/viewvc/commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarUtils.java?rev=1358504&r1=1358503&r2=1358504&view=diff
==============================================================================
--- commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarUtils.java
(original)
+++ commons/proper/compress/trunk/src/main/java/org/apache/commons/compress/archivers/tar/TarUtils.java
Sat Jul  7 05:19:39 2012
@@ -18,6 +18,9 @@
  */
 package org.apache.commons.compress.archivers.tar;
 
+import static org.apache.commons.compress.archivers.tar.TarConstants.CHKSUMLEN;
+import static org.apache.commons.compress.archivers.tar.TarConstants.CHKSUM_OFFSET;
+
 import java.io.IOException;
 import java.math.BigInteger;
 import java.nio.ByteBuffer;
@@ -558,4 +561,63 @@ public class TarUtils {
         return sum;
     }
 
+    /**
+     * Wikipedia <a href="http://en.wikipedia.org/wiki/Tar_(file_format)#File_header">says</a>:
+     * <blockquote>
+     * The checksum is calculated by taking the sum of the unsigned byte values
+     * of the header block with the eight checksum bytes taken to be ascii
+     * spaces (decimal value 32). It is stored as a six digit octal number with
+     * leading zeroes followed by a NUL and then a space. Various
+     * implementations do not adhere to this format. For better compatibility,
+     * ignore leading and trailing whitespace, and get the first six digits. In
+     * addition, some historic tar implementations treated bytes as signed.
+     * Implementations typically calculate the checksum both ways, and treat it
+     * as good if either the signed or unsigned sum matches the included
+     * checksum.
+     * </blockquote>
+     * <p>
+     * In addition there are
+     * <a href="https://issues.apache.org/jira/browse/COMPRESS-117">some tar files</a>
+     * that seem to have parts of their header cleared to zero (no detectable
+     * magic bytes, etc.) but still have a reasonable-looking checksum field
+     * present. It looks like we can detect such cases reasonably well by
+     * checking whether the stored checksum is <em>greater than</em> the
+     * computed unsigned checksum. That check is unlikely to pass on some
+     * random file header, as it would need to have a valid sequence of
+     * octal digits in just the right place.
+     * <p>
+     * The return value of this method should be treated as a best-effort
+     * heuristic rather than an absolute and final truth. The checksum
+     * verification logic may well evolve over time as more special cases
+     * are encountered.
+     *
+     * @param header tar header
+     * @return whether the checksum is reasonably good
+     * @see <a href="https://issues.apache.org/jira/browse/COMPRESS-191">COMPRESS-191</a>
+     * @since 1.5
+     */
+    public static boolean verifyCheckSum(byte[] header) {
+        long storedSum = 0;
+        long unsignedSum = 0;
+        long signedSum = 0;
+
+        int digits = 0;
+        for (int i = 0; i < header.length; i++) {
+            byte b = header[i];
+            if (CHKSUM_OFFSET  <= i && i < CHKSUM_OFFSET + CHKSUMLEN) {
+                if ('0' <= b && b <= '7' && digits++ < 6) {
+                    storedSum = storedSum * 8 + b - '0';
+                } else if (digits > 0) {
+                    digits = 6; // only look at the first octal digit sequence
+                }
+                b = ' ';
+            }
+            unsignedSum += 0xff & b;
+            signedSum += b;
+        }
+
+        return storedSum == unsignedSum || storedSum == signedSum
+                || storedSum > unsignedSum; // COMPRESS-177
+    }
+
 }

Modified: commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveEntryTest.java
URL: http://svn.apache.org/viewvc/commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveEntryTest.java?rev=1358504&r1=1358503&r2=1358504&view=diff
==============================================================================
--- commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveEntryTest.java
(original)
+++ commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveEntryTest.java
Sat Jul  7 05:19:39 2012
@@ -80,15 +80,19 @@ public class TarArchiveEntryTest extends
             t = tin.getNextTarEntry();
             assertNotNull(t);
             assertEquals("/", t.getName());
+            assertTrue(t.isCheckSumOK());
             t = tin.getNextTarEntry();
             assertNotNull(t);
             assertEquals("foo.txt", t.getName());
+            assertTrue(t.isCheckSumOK());
             t = tin.getNextTarEntry();
             assertNotNull(t);
             assertEquals("bar.txt", t.getName());
+            assertTrue(t.isCheckSumOK());
             t = tin.getNextTarEntry();
             assertNotNull(t);
             assertEquals("baz.txt", t.getName());
+            assertTrue(t.isCheckSumOK());
         } finally {
             if (tin != null) {
                 tin.close();

Modified: commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveInputStreamTest.java
URL: http://svn.apache.org/viewvc/commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveInputStreamTest.java?rev=1358504&r1=1358503&r2=1358504&view=diff
==============================================================================
--- commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveInputStreamTest.java
(original)
+++ commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarArchiveInputStreamTest.java
Sat Jul  7 05:19:39 2012
@@ -76,6 +76,7 @@ public class TarArchiveInputStreamTest {
             assertEquals("sample/link-to-txt-file.lnk", tae.getName());
             assertEquals(new Date(0), tae.getLastModifiedDate());
             assertTrue(tae.isSymbolicLink());
+            assertTrue(tae.isCheckSumOK());
         } finally {
             if (in != null) {
                 in.close();
@@ -105,6 +106,7 @@ public class TarArchiveInputStreamTest {
             cal.set(1969, 11, 31, 23, 59, 59);
             cal.set(Calendar.MILLISECOND, 0);
             assertEquals(cal.getTime(), tae.getLastModifiedDate());
+            assertTrue(tae.isCheckSumOK());
         } finally {
             if (in != null) {
                 in.close();

Modified: commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarUtilsTest.java
URL: http://svn.apache.org/viewvc/commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarUtilsTest.java?rev=1358504&r1=1358503&r2=1358504&view=diff
==============================================================================
--- commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarUtilsTest.java
(original)
+++ commons/proper/compress/trunk/src/test/java/org/apache/commons/compress/archivers/tar/TarUtilsTest.java
Sat Jul  7 05:19:39 2012
@@ -239,4 +239,97 @@ public class TarUtilsTest extends TestCa
         assertEquals(-3601l, TarUtils.parseOctalOrBinary(b, 0, 8));
     }
 
+    // https://issues.apache.org/jira/browse/COMPRESS-191
+    public void testVerifyHeaderCheckSum() {
+        byte[] valid = { // from bla.tar
+                116, 101, 115, 116, 49, 46, 120, 109, 108, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 48, 48, 48, 48, 54, 52, 52, 0, 48, 48, 48, 48, 55, 54, 53,
+                0, 48, 48, 48, 48, 55, 54, 53, 0, 48, 48, 48, 48, 48, 48, 48,
+                49, 49, 52, 50, 0, 49, 48, 55, 49, 54, 53, 52, 53, 54, 50, 54,
+                0, 48, 49, 50, 50, 54, 48, 0, 32, 48, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 117, 115, 116, 97, 114, 32, 32, 0,
+                116, 99, 117, 114, 100, 116, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 116, 99, 117,
+                114, 100, 116, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0 };
+        assertTrue(TarUtils.verifyCheckSum(valid));
+
+        byte[] compress117 = { // from COMPRESS-117
+                116, 101, 115, 116, 49, 46, 120, 109, 108, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 48, 48, 48, 48, 54, 52, 52, 0, 48, 48, 48, 48, 55, 54, 53,
+                0, 48, 48, 48, 48, 55, 54, 53, 0, 48, 48, 48, 48, 48, 48, 48,
+                49, 49, 52, 50, 0, 49, 48, 55, 49, 54, 53, 52, 53, 54, 50, 54,
+                0, 48, 49, 50, 50, 54, 48, 0, 32, 48, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+        assertTrue(TarUtils.verifyCheckSum(compress117));
+
+        byte[] invalid = { // from the testAIFF.aif file in Tika
+                70, 79, 82, 77, 0, 0, 15, 46, 65, 73, 70, 70, 67, 79, 77, 77,
+                0, 0, 0, 18, 0, 2, 0, 0, 3, -64, 0, 16, 64, 14, -84, 68, 0, 0,
+                0, 0, 0, 0, 83, 83, 78, 68, 0, 0, 15, 8, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 1, -1, -1, 0, 1, -1, -1, 0, 0, 0, 0, 0, 0, 0, 1, -1, -1,
+                0, 0, 0, 0, 0, 0, -1, -1, 0, 2, -1, -2, 0, 2, -1, -1, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 1, -1, -1, 0, 0, -1, -1, 0, 1, 0, 0, 0, 0,
+                0, 0, 0, 1, -1, -1, 0, 1, -1, -2, 0, 1, -1, -1, 0, 1, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0,
+                2, -1, -2, 0, 2, -1, -1, 0, 0, 0, 1, -1, -1, 0, 1, -1, -1, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 1, -1, -2, 0, 2, -1, -2, 0, 1, 0, 0,
+                0, 1, -1, -1, 0, 0, 0, 1, -1, -1, 0, 0, 0, 1, -1, -2, 0, 2,
+                -1, -1, 0, 0, 0, 0, 0, 0, -1, -1, 0, 1, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0, 1, -1, -1, 0, 2, -1, -2,
+                0, 2, -1, -2, 0, 2, -1, -2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, -1,
+                -2, 0, 2, -1, -2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                -1, -1, 0, 1, 0, 0, -1, -1, 0, 2, -1, -2, 0, 2, -1, -1, 0, 0,
+                0, 0, 0, 0, -1, -1, 0, 1, -1, -1, 0, 1, -1, -1, 0, 2, -1, -2,
+                0, 1, 0, 0, -1, -1, 0, 2, -1, -2, 0, 2, -1, -2, 0, 1, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, -1, 0, 0, 0,
+                0, -1, -1, 0, 1, 0, 0, 0, 0, 0, 1, -1, -1, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, -2, 0, 2, -1, -1, 0,
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, -2, 0, 1, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 0, 1, -1, -1, 0, 0, 0, 0, -1, -1, 0, 2, -1, -2,
+                0, 2, -1, -2, 0, 2, -1, -1, 0, 0, 0, 0, -1, -1, 0, 1, -1, -1,
+                0, 1, -1, -1, 0, 1, -1, -1, 0, 1, -1, -1, 0, 1, 0, 0, 0, 0,
+                -1, -1, 0, 2, -1, -2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                1, -1, -1, 0, 0, 0, 0, -1, -1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0,
+                0, 0, 0, 0, 0, 1 };
+        assertFalse(TarUtils.verifyCheckSum(invalid));
+    }
+
 }



Mime
View raw message