/*
* Copyright (c) 2016, 2018, 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
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package sun.tools.jar;
import jdk.internal.org.objectweb.asm.*;
import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
/**
* A FingerPrint is an abstract representation of a JarFile entry that contains
* information to determine if the entry represents a class or a
* resource, and whether two entries are identical. If the FingerPrint represents
* a class, it also contains information to (1) describe the public API;
* (2) compare the public API of this class with another class; (3) determine
* whether or not it's a nested class and, if so, the name of the associated
* outer class; and (4) for an canonically ordered set of classes determine
* if the class versions are compatible. A set of classes is canonically
* ordered if the classes in the set have the same name, and the base class
* precedes the versioned classes and if each versioned class with version
* {@code n} precedes classes with versions {@code > n} for all versions
* {@code n}.
*/
final class FingerPrint {
private static final MessageDigest MD;
private final String basename;
private final String entryName;
private final int mrversion;
private final byte[] sha1;
private final ClassAttributes attrs;
private final boolean isClassEntry;
static {
try {
MD = MessageDigest.getInstance("SHA-1");
} catch (NoSuchAlgorithmException x) {
// log big problem?
throw new RuntimeException(x);
}
}
public FingerPrint(String basename, String entryName, int mrversion, byte[] bytes)
throws IOException {
this.basename = basename;
this.entryName = entryName;
this.mrversion = mrversion;
if (isCafeBabe(bytes)) {
isClassEntry = true;
sha1 = sha1(bytes, 8); // skip magic number and major/minor version
attrs = getClassAttributes(bytes);
} else {
isClassEntry = false;
sha1 = null;
attrs = null;
}
}
public boolean isClass() {
return isClassEntry;
}
public boolean isNestedClass() {
return attrs.nestedClass;
}
public boolean isPublicClass() {
return attrs.publicClass;
}
public boolean isIdentical(FingerPrint that) {
if (that == null) return false;
if (this == that) return true;
return isEqual(this.sha1, that.sha1);
}
public boolean isCompatibleVersion(FingerPrint that) {
return attrs.version >= that.attrs.version;
}
public boolean isSameAPI(FingerPrint that) {
if (that == null) return false;
return attrs.equals(that.attrs);
}
public String basename() {
return basename;
}
public String entryName() {
return entryName;
}
public String className() {
return attrs.name;
}
public int mrversion() {
return mrversion;
}
public String outerClassName() {
return attrs.outerClassName;
}
private byte[] sha1(byte[] entry) {
MD.update(entry);
return MD.digest();
}
private byte[] sha1(byte[] entry, int offset) {
MD.update(entry, offset, entry.length - offset);
return MD.digest();
}
private boolean isEqual(byte[] sha1_1, byte[] sha1_2) {
return MessageDigest.isEqual(sha1_1, sha1_2);
}
private static final byte[] cafeBabe = {(byte)0xca, (byte)0xfe, (byte)0xba, (byte)0xbe};
private boolean isCafeBabe(byte[] bytes) {
if (bytes.length < 4) return false;
for (int i = 0; i < 4; i++) {
if (bytes[i] != cafeBabe[i]) {
return false;
}
}
return true;
}
private ClassAttributes getClassAttributes(byte[] bytes) {
ClassReader rdr = new ClassReader(bytes);
ClassAttributes attrs = new ClassAttributes();
rdr.accept(attrs, 0);
return attrs;
}
private static final class Field {
private final int access;
private final String name;
private final String desc;
Field(int access, String name, String desc) {
this.access = access;
this.name = name;
this.desc = desc;
}
@Override
public boolean equals(Object that) {
if (that == null) return false;
if (this == that) return true;
if (!(that instanceof Field)) return false;
Field field = (Field)that;
return (access == field.access) && name.equals(field.name)
&& desc.equals(field.desc);
}
@Override
public int hashCode() {
int result = 17;
result = 37 * result + access;
result = 37 * result + name.hashCode();
result = 37 * result + desc.hashCode();
return result;
}
}
private static final class Method {
private final int access;
private final String name;
private final String desc;
private final Set<String> exceptions;
Method(int access, String name, String desc, Set<String> exceptions) {
this.access = access;
this.name = name;
this.desc = desc;
this.exceptions = exceptions;
}
@Override
public boolean equals(Object that) {
if (that == null) return false;
if (this == that) return true;
if (!(that instanceof Method)) return false;
Method method = (Method)that;
return (access == method.access) && name.equals(method.name)
&& desc.equals(method.desc)
&& exceptions.equals(method.exceptions);
}
@Override
public int hashCode() {
int result = 17;
result = 37 * result + access;
result = 37 * result + name.hashCode();
result = 37 * result + desc.hashCode();
result = 37 * result + exceptions.hashCode();
return result;
}
}
private static final class ClassAttributes extends ClassVisitor {
private String name;
private String outerClassName;
private String superName;
private int version;
private int access;
private boolean publicClass;
private boolean nestedClass;
private final Set<Field> fields = new HashSet<>();
private final Set<Method> methods = new HashSet<>();
public ClassAttributes() {
super(Opcodes.ASM7);
}
private boolean isPublic(int access) {
return ((access & Opcodes.ACC_PUBLIC) == Opcodes.ACC_PUBLIC)
|| ((access & Opcodes.ACC_PROTECTED) == Opcodes.ACC_PROTECTED);
}
@Override
public void visit(int version, int access, String name, String signature,
String superName, String[] interfaces) {
this.version = version;
this.access = access;
this.name = name;
this.nestedClass = name.contains("$");
this.superName = superName;
this.publicClass = isPublic(access);
}
@Override
public void visitOuterClass(String owner, String name, String desc) {
if (!this.nestedClass) return;
this.outerClassName = owner;
}
@Override
public void visitInnerClass(String name, String outerName, String innerName,
int access) {
if (!this.nestedClass) return;
if (outerName == null) return;
if (!this.name.equals(name)) return;
if (this.outerClassName == null) this.outerClassName = outerName;
}
@Override
public FieldVisitor visitField(int access, String name, String desc,
String signature, Object value) {
if (isPublic(access)) {
fields.add(new Field(access, name, desc));
}
return null;
}
@Override
public MethodVisitor visitMethod(int access, String name, String desc,
String signature, String[] exceptions) {
if (isPublic(access)) {
Set<String> exceptionSet = new HashSet<>();
if (exceptions != null) {
for (String e : exceptions) {
exceptionSet.add(e);
}
}
// treat type descriptor as a proxy for signature because signature
// is usually null, need to strip off the return type though
int n;
if (desc != null && (n = desc.lastIndexOf(')')) != -1) {
desc = desc.substring(0, n + 1);
methods.add(new Method(access, name, desc, exceptionSet));
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