8233234: Better Zip Naming

Reviewed-by: alanb, ahgross, redestad, coffeys, mschoene, rhalade

src/java.base/share/classes/java/util/zip/ZipCoder.java

@@ -86,10 +86,14 @@ class ZipCoder {
         }
     }
 
-    String toStringUTF8(byte[] ba, int len) {
+    static String toStringUTF8(byte[] ba, int len) {
         return UTF8.toString(ba, 0, len);
     }
 
+    static String toStringUTF8(byte[] ba, int off, int len) {
+        return UTF8.toString(ba, off, len);
+    }
+
     boolean isUTF8() {
         return false;
     }

src/java.base/share/classes/java/util/zip/ZipFile.java

@@ -790,7 +790,6 @@ public class ZipFile implements ZipConstants, Closeable {
                 throw new UncheckedIOException(ioe);
             }
         }
-
     }
 
     /**
@@ -1296,6 +1295,44 @@ public class ZipFile implements ZipConstants, Closeable {
             }
         }
 
+        private static final void checkUTF8(byte[] a, int pos, int len) throws ZipException {
+            try {
+                int end = pos + len;
+                while (pos < end) {
+                    // ASCII fast-path: When checking that a range of bytes is
+                    // valid UTF-8, we can avoid some allocation by skipping
+                    // past bytes in the 0-127 range
+                    if (a[pos] < 0) {
+                        ZipCoder.toStringUTF8(a, pos, end - pos);
+                        break;
+                    }
+                    pos++;
+                }
+            } catch(Exception e) {
+                zerror("invalid CEN header (bad entry name)");
+            }
+        }
+
+        private final void checkEncoding(ZipCoder zc, byte[] a, int pos, int nlen) throws ZipException {
+            try {
+                zc.toString(a, pos, nlen);
+            } catch(Exception e) {
+                zerror("invalid CEN header (bad entry name)");
+            }
+        }
+
+        private static final int hashN(byte[] a, int off, int len) {
+            int h = 1;
+            while (len-- > 0) {
+                h = 31 * h + a[off++];
+            }
+            return h;
+        }
+
+        private static final int hash_append(int hash, byte b) {
+            return hash * 31 + b;
+        }
+
         private static class End {
             int  centot;     // 4 bytes
             long cenlen;     // 4 bytes
@@ -1474,12 +1511,18 @@ public class ZipFile implements ZipConstants, Closeable {
                 int nlen   = CENNAM(cen, pos);
                 int elen   = CENEXT(cen, pos);
                 int clen   = CENCOM(cen, pos);
-                if ((CENFLG(cen, pos) & 1) != 0)
+                int flag   = CENFLG(cen, pos);
+                if ((flag & 1) != 0)
                     zerror("invalid CEN header (encrypted entry)");
                 if (method != STORED && method != DEFLATED)
                     zerror("invalid CEN header (bad compression method: " + method + ")");
                 if (entryPos + nlen > limit)
                     zerror("invalid CEN header (bad header size)");
+                if (zc.isUTF8() || (flag & USE_UTF8) != 0) {
+                    checkUTF8(cen, pos + CENHDR, nlen);
+                } else {
+                    checkEncoding(zc, cen, pos + CENHDR, nlen);
+                }
                 // Record the CEN offset and the name hash in our hash cell.
                 hash = zipCoderForPos(pos).normalizedHash(cen, entryPos, nlen);
                 hsh = (hash & 0x7fffffff) % tablelen;

src/java.base/share/classes/java/util/zip/ZipInputStream.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1996, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -298,7 +298,7 @@ public class ZipInputStream extends InflaterInputStream implements ZipConstants
         readFully(b, 0, len);
         // Force to use UTF-8 if the USE_UTF8 bit is ON
         ZipEntry e = createZipEntry(((flag & USE_UTF8) != 0)
-                                    ? zc.toStringUTF8(b, len)
+                                    ? ZipCoder.toStringUTF8(b, len)
                                     : zc.toString(b, len));
         // now get the remaining fields for the entry
         if ((flag & 1) == 1) {

src/jdk.zipfs/share/classes/jdk/nio/zipfs/ZipFileSystem.java

@@ -1550,7 +1550,8 @@ class ZipFileSystem extends FileSystem {
             int nlen   = CENNAM(cen, pos);
             int elen   = CENEXT(cen, pos);
             int clen   = CENCOM(cen, pos);
-            if ((CENFLG(cen, pos) & 1) != 0) {
+            int flag   = CENFLG(cen, pos);
+            if ((flag & 1) != 0) {
                 throw new ZipException("invalid CEN header (encrypted entry)");
             }
             if (method != METHOD_STORED && method != METHOD_DEFLATED) {
@@ -1561,7 +1562,11 @@ class ZipFileSystem extends FileSystem {
             }
             IndexNode inode = new IndexNode(cen, pos, nlen);
             inodes.put(inode, inode);
-
+            if (zc.isUTF8() || (flag & FLAG_USE_UTF8) != 0) {
+                checkUTF8(inode.name);
+            } else {
+                checkEncoding(inode.name);
+            }
             // skip ext and comment
             pos += (CENHDR + nlen + elen + clen);
         }
@@ -1572,6 +1577,34 @@ class ZipFileSystem extends FileSystem {
         return cen;
     }
 
+    private  final void checkUTF8(byte[] a) throws ZipException {
+        try {
+            int end = a.length;
+            int pos = 0;
+            while (pos < end) {
+                // ASCII fast-path: When checking that a range of bytes is
+                // valid UTF-8, we can avoid some allocation by skipping
+                // past bytes in the 0-127 range
+                if (a[pos] < 0) {
+                    zc.toString(Arrays.copyOfRange(a, pos, a.length));
+                    break;
+                }
+                pos++;
+            }
+        } catch(Exception e) {
+            throw new ZipException("invalid CEN header (bad entry name)");
+        }
+    }
+
+    private final void checkEncoding( byte[] a) throws ZipException {
+        try {
+            zc.toString(a);
+        } catch(Exception e) {
+            throw new ZipException("invalid CEN header (bad entry name)");
+        }
+    }
+
+
     private void ensureOpen() {
         if (!isOpen)
             throw new ClosedFileSystemException();