scouter.agent.asm.SocketASM.java Source code

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Here is the source code for scouter.agent.asm.SocketASM.java

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/*
 *  Copyright 2015 the original author or authors. 
 *  @https://github.com/scouter-project/scouter
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); 
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License. 
 */

package scouter.agent.asm;

import org.objectweb.asm.*;
import org.objectweb.asm.commons.LocalVariablesSorter;
import scouter.agent.ClassDesc;
import scouter.agent.Configure;
import scouter.agent.asm.util.AsmUtil;
import scouter.agent.asm.util.HookingSet;
import scouter.agent.trace.TraceApiCall;

import java.util.HashMap;
import java.util.Map;

public class SocketASM implements IASM, Opcodes {
    private Map<String, HookingSet> reserved = new HashMap<String, HookingSet>();

    public SocketASM() {
        AsmUtil.add(reserved, "java/net/Socket", "connect(Ljava/net/SocketAddress;I)V");
        //AsmUtil.add(reserved,"java/nio/channels/SocketChannel","connect(Ljava/net/SocketAddress;)Z");
        AsmUtil.add(reserved, "sun/nio/ch/SocketChannelImpl", "connect(Ljava/net/SocketAddress;)Z");
    }

    public ClassVisitor transform(ClassVisitor cv, String className, ClassDesc classDesc) {
        if (Configure.getInstance()._hook_socket_enabled == false) {
            return cv;
        }
        HookingSet mset = reserved.get(className);
        if (mset != null) {
            return new SocketCV(cv, mset, className);
        }
        return cv;
    }
}

class SocketCV extends ClassVisitor implements Opcodes {

    public String className;
    private HookingSet mset;

    public SocketCV(ClassVisitor cv, HookingSet mset, String className) {
        super(ASM7, cv);
        this.mset = mset;
        this.className = className;
    }

    @Override
    public MethodVisitor visitMethod(int access, String methodName, String desc, String signature,
            String[] exceptions) {
        MethodVisitor mv = super.visitMethod(access, methodName, desc, signature, exceptions);
        if (mv == null || mset.isA(methodName, desc) == false) {
            return mv;
        }
        if (AsmUtil.isSpecial(methodName)) {
            return mv;
        }

        return new SocketMV(access, desc, mv);
    }
}

// ///////////////////////////////////////////////////////////////////////////
class SocketMV extends LocalVariablesSorter implements Opcodes {
    private static final String TRACEAPICALL = TraceApiCall.class.getName().replace('.', '/');
    private final static String START_METHOD = "startSocket";
    private static final String START_SIGNATURE = "(Ljava/lang/Object;Ljava/net/SocketAddress;)Ljava/lang/Object;";
    private final static String END_METHOD = "endSocket";
    private static final String END_SIGNATURE = "(Ljava/lang/Object;Ljava/lang/Throwable;)V";

    private Label startFinally = new Label();

    public SocketMV(int access, String desc, MethodVisitor mv) {
        super(ASM7, access, desc, mv);
    }

    private int statIdx;

    public void visitCode() {
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, TRACEAPICALL, START_METHOD, START_SIGNATURE, false);

        statIdx = newLocal(Type.getType(Object.class));

        mv.visitVarInsn(Opcodes.ASTORE, statIdx);
        mv.visitLabel(startFinally);
        mv.visitCode();
    }

    @Override
    public void visitInsn(int opcode) {
        if ((opcode >= IRETURN && opcode <= RETURN)) {
            mv.visitVarInsn(Opcodes.ALOAD, statIdx);
            mv.visitInsn(Opcodes.ACONST_NULL);
            mv.visitMethodInsn(Opcodes.INVOKESTATIC, TRACEAPICALL, END_METHOD, END_SIGNATURE, false);
        }
        mv.visitInsn(opcode);
    }

    @Override
    public void visitMaxs(int maxStack, int maxLocals) {
        Label endFinally = new Label();
        mv.visitTryCatchBlock(startFinally, endFinally, endFinally, null);
        mv.visitLabel(endFinally);
        mv.visitInsn(DUP);
        int errIdx = newLocal(Type.getType(Throwable.class));
        mv.visitVarInsn(Opcodes.ASTORE, errIdx);

        mv.visitVarInsn(Opcodes.ALOAD, statIdx);
        mv.visitVarInsn(Opcodes.ALOAD, errIdx);
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, TRACEAPICALL, END_METHOD, END_SIGNATURE, false);
        mv.visitInsn(ATHROW);
        mv.visitMaxs(maxStack + 8, maxLocals + 2);
    }
}