feat: support bytecode shrink

1. remove source file symbol (#46)
2. remove debug info when enable shrink (#29)

common/src/main/java/com/reajason/javaweb/ClassBytesShrink.java

@@ -0,0 +1,26 @@
+package com.reajason.javaweb;
+
+import net.bytebuddy.jar.asm.ClassReader;
+import net.bytebuddy.jar.asm.ClassVisitor;
+import net.bytebuddy.jar.asm.ClassWriter;
+import net.bytebuddy.jar.asm.Opcodes;
+
+/**
+ * @author ReaJason
+ * @since 2025/2/25
+ */
+public class ClassBytesShrink {
+
+    public static byte[] shrink(byte[] bytes, boolean full) {
+        ClassReader cr = new ClassReader(bytes);
+        ClassWriter cw = new ClassWriter(0);
+        ClassVisitor cv = new ClassVisitor(Opcodes.ASM9, cw) {
+            @Override
+            public void visitSource(String source, String debug) {
+
+            }
+        };
+        cr.accept(cv, full ? ClassReader.SKIP_DEBUG : 0);
+        return cw.toByteArray();
+    }
+}

generator/src/main/java/com/reajason/javaweb/memshell/MemShellGenerator.java

@@ -62,7 +62,7 @@ public class MemShellGenerator {
             case Godzilla:
                 return new GodzillaGenerator(shellConfig, (GodzillaConfig) shellToolConfig).getBytes();
             case Command:
-                return CommandGenerator.generate(shellConfig, (CommandConfig) shellToolConfig);
+                return new CommandGenerator(shellConfig, (CommandConfig) shellToolConfig).getBytes();
             case Behinder:
                 return new BehinderGenerator(shellConfig, (BehinderConfig) shellToolConfig).getBytes();
             case Suo5:

generator/src/main/java/com/reajason/javaweb/memshell/config/ShellConfig.java

@@ -57,6 +57,12 @@ public class ShellConfig {
     @Builder.Default
     private boolean debug = false;
 
+    /**
+     * 是否启用缩小字节码
+     */
+    @Builder.Default
+    private boolean shrink = false;
+
     public boolean isDebugOff() {
         return !debug;
     }

generator/src/main/java/com/reajason/javaweb/memshell/generator/AntSwordGenerator.java

@@ -1,5 +1,6 @@
 package com.reajason.javaweb.memshell.generator;
 
+import com.reajason.javaweb.ClassBytesShrink;
 import com.reajason.javaweb.buddy.LdcReAssignVisitorWrapper;
 import com.reajason.javaweb.buddy.LogRemoveMethodVisitor;
 import com.reajason.javaweb.buddy.ServletRenameVisitorWrapper;
@@ -19,7 +20,7 @@ import static net.bytebuddy.matcher.ElementMatchers.named;
  * @author ReaJason
  * @since 2025/02/18
  */
-public class  AntSwordGenerator {
+public class AntSwordGenerator {
     private final ShellConfig shellConfig;
     private final AntSwordConfig antSwordConfig;
 
@@ -67,7 +68,7 @@ public class  AntSwordGenerator {
     public byte[] getBytes() {
         DynamicType.Builder<?> builder = getBuilder();
         try (DynamicType.Unloaded<?> make = builder.make()) {
-            return make.getBytes();
+            return ClassBytesShrink.shrink(make.getBytes(), shellConfig.isShrink());
         }
     }
 }

generator/src/main/java/com/reajason/javaweb/memshell/generator/BehinderGenerator.java

@@ -1,5 +1,6 @@
 package com.reajason.javaweb.memshell.generator;
 
+import com.reajason.javaweb.ClassBytesShrink;
 import com.reajason.javaweb.buddy.LdcReAssignVisitorWrapper;
 import com.reajason.javaweb.buddy.LogRemoveMethodVisitor;
 import com.reajason.javaweb.buddy.ServletRenameVisitorWrapper;
@@ -70,7 +71,7 @@ public class BehinderGenerator {
     public byte[] getBytes() {
         DynamicType.Builder<?> builder = getBuilder();
         try (DynamicType.Unloaded<?> make = builder.make()) {
-            return make.getBytes();
+            return ClassBytesShrink.shrink(make.getBytes(), shellConfig.isShrink());
         }
     }
 }

generator/src/main/java/com/reajason/javaweb/memshell/generator/CommandGenerator.java

@@ -1,5 +1,6 @@
 package com.reajason.javaweb.memshell.generator;
 
+import com.reajason.javaweb.ClassBytesShrink;
 import com.reajason.javaweb.buddy.LdcReAssignVisitorWrapper;
 import com.reajason.javaweb.buddy.LogRemoveMethodVisitor;
 import com.reajason.javaweb.buddy.ServletRenameVisitorWrapper;
@@ -20,40 +21,52 @@ import static net.bytebuddy.matcher.ElementMatchers.named;
  * @since 2024/11/24
  */
 public class CommandGenerator {
+    private final ShellConfig shellConfig;
+    private final CommandConfig commandConfig;
 
-    public static byte[] generate(ShellConfig config, CommandConfig shellConfig) {
+    public CommandGenerator(ShellConfig shellConfig, CommandConfig commandConfig) {
-        if (shellConfig.getShellClass() == null) {
+        this.shellConfig = shellConfig;
-            throw new IllegalArgumentException("shellConfig.getClazz() == null");
+        this.commandConfig = commandConfig;
+    }
+
+    public DynamicType.Builder<?> getBuilder() {
+        if (commandConfig.getShellClass() == null) {
+            throw new IllegalArgumentException("commandConfig.getClazz() == null");
         }
 
         DynamicType.Builder<?> builder = new ByteBuddy()
-                .redefine(shellConfig.getShellClass())
+                .redefine(commandConfig.getShellClass())
-                .name(shellConfig.getShellClassName())
+                .name(commandConfig.getShellClassName())
-                .visit(new TargetJreVersionVisitorWrapper(config.getTargetJreVersion()));
+                .visit(new TargetJreVersionVisitorWrapper(shellConfig.getTargetJreVersion()));
 
-        if (config.isJakarta()) {
+        if (shellConfig.isJakarta()) {
             builder = builder.visit(ServletRenameVisitorWrapper.INSTANCE);
         }
 
-        if (config.isDebugOff()) {
+        if (shellConfig.isDebugOff()) {
             builder = LogRemoveMethodVisitor.extend(builder);
         }
 
-        String shellType = config.getShellType();
+        String shellType = shellConfig.getShellType();
         if (!ShellType.WEBSOCKET.equals(shellType)) {
             if (StringUtils.startsWith(shellType, ShellType.AGENT)) {
                 builder = builder.visit(
                         new LdcReAssignVisitorWrapper(new HashMap<Object, Object>(1) {{
-                            put("paramName", shellConfig.getParamName());
+                            put("paramName", commandConfig.getParamName());
                         }})
                 );
             } else {
-                builder = builder.field(named("paramName")).value(shellConfig.getParamName());
+                builder = builder.field(named("paramName")).value(commandConfig.getParamName());
             }
         }
 
+        return builder;
+    }
+
+    public byte[] getBytes() {
+        DynamicType.Builder<?> builder = getBuilder();
         try (DynamicType.Unloaded<?> make = builder.make()) {
-            return make.getBytes();
+            return ClassBytesShrink.shrink(make.getBytes(), shellConfig.isShrink());
         }
     }
 }

generator/src/main/java/com/reajason/javaweb/memshell/generator/GodzillaGenerator.java

@@ -1,5 +1,6 @@
 package com.reajason.javaweb.memshell.generator;
 
+import com.reajason.javaweb.ClassBytesShrink;
 import com.reajason.javaweb.buddy.LdcReAssignVisitorWrapper;
 import com.reajason.javaweb.buddy.LogRemoveMethodVisitor;
 import com.reajason.javaweb.buddy.ServletRenameVisitorWrapper;
@@ -75,7 +76,7 @@ public class GodzillaGenerator {
     public byte[] getBytes() {
         DynamicType.Builder<?> builder = getBuilder();
         try (DynamicType.Unloaded<?> make = builder.make()) {
-            return make.getBytes();
+            return ClassBytesShrink.shrink(make.getBytes(), shellConfig.isShrink());
         }
     }
 }

generator/src/main/java/com/reajason/javaweb/memshell/generator/InjectorGenerator.java

@@ -1,5 +1,6 @@
 package com.reajason.javaweb.memshell.generator;
 
+import com.reajason.javaweb.ClassBytesShrink;
 import com.reajason.javaweb.buddy.ByPassJavaModuleInterceptor;
 import com.reajason.javaweb.buddy.LogRemoveMethodVisitor;
 import com.reajason.javaweb.buddy.ServletRenameVisitorWrapper;
@@ -22,11 +23,11 @@ import static net.bytebuddy.matcher.ElementMatchers.named;
  * @since 2024/11/24
  */
 public class InjectorGenerator {
-    private final ShellConfig config;
+    private final ShellConfig shellConfig;
     private final InjectorConfig injectorConfig;
 
-    public InjectorGenerator(ShellConfig config, InjectorConfig injectorConfig) {
+    public InjectorGenerator(ShellConfig shellConfig, InjectorConfig injectorConfig) {
-        this.config = config;
+        this.shellConfig = shellConfig;
         this.injectorConfig = injectorConfig;
     }
 
@@ -36,20 +37,20 @@ public class InjectorGenerator {
         DynamicType.Builder<?> builder = new ByteBuddy()
                 .redefine(injectorConfig.getInjectorClass())
                 .name(injectorConfig.getInjectorClassName())
-                .visit(new TargetJreVersionVisitorWrapper(config.getTargetJreVersion()))
+                .visit(new TargetJreVersionVisitorWrapper(shellConfig.getTargetJreVersion()))
                 .method(named("getUrlPattern")).intercept(FixedValue.value(Objects.toString(injectorConfig.getUrlPattern(), "/*")))
                 .method(named("getBase64String")).intercept(FixedValue.value(base64String))
                 .method(named("getClassName")).intercept(FixedValue.value(injectorConfig.getShellClassName()));
 
-        if (config.needByPassJavaModule()) {
+        if (shellConfig.needByPassJavaModule()) {
             builder = ByPassJavaModuleInterceptor.extend(builder);
         }
 
-        if (config.isJakarta()) {
+        if (shellConfig.isJakarta()) {
             builder = builder.visit(ServletRenameVisitorWrapper.INSTANCE);
         }
 
-        if (config.isDebugOff()) {
+        if (shellConfig.isDebugOff()) {
             builder = LogRemoveMethodVisitor.extend(builder);
         }
         return builder;
@@ -59,7 +60,7 @@ public class InjectorGenerator {
     public byte[] generate() {
         DynamicType.Builder<?> builder = getBuilder();
         try (DynamicType.Unloaded<?> make = builder.make()) {
-            return make.getBytes();
+            return ClassBytesShrink.shrink(make.getBytes(), shellConfig.isShrink());
         }
     }
 }

generator/src/main/java/com/reajason/javaweb/memshell/generator/Suo5Generator.java

@@ -1,5 +1,6 @@
 package com.reajason.javaweb.memshell.generator;
 
+import com.reajason.javaweb.ClassBytesShrink;
 import com.reajason.javaweb.buddy.LdcReAssignVisitorWrapper;
 import com.reajason.javaweb.buddy.LogRemoveMethodVisitor;
 import com.reajason.javaweb.buddy.ServletRenameVisitorWrapper;
@@ -59,7 +60,7 @@ public class Suo5Generator {
     public byte[] getBytes() {
         DynamicType.Builder<?> builder = getBuilder();
         try (DynamicType.Unloaded<?> make = builder.make()) {
-            return make.getBytes();
+            return ClassBytesShrink.shrink(make.getBytes(), shellConfig.isShrink());
         }
     }
 }

generator/src/test/java/com/reajason/javaweb/memshell/tomcat/command/CommandFilterTest.java

@@ -42,7 +42,7 @@ class CommandFilterTest {
                 .paramName("cmd")
                 .build();
         generateConfig.setShellType(shellType);
-        byte[] bytes = CommandGenerator.generate(generateConfig, shellConfig);
+        byte[] bytes = new CommandGenerator(generateConfig, shellConfig).getBytes();
         Object obj = ClassUtils.newInstance(bytes);
         assertEquals(shellConfig.getShellClassName(), obj.getClass().getName());
         assertEquals(shellConfig.getParamName(), ClassUtils.getFieldValue(obj, "paramName"));

web/src/components/main-config-card.tsx

@@ -260,6 +260,18 @@ export function MainConfigCard({
                 </FormItem>
               )}
             />
+            <FormField
+              control={form.control}
+              name="shrink"
+              render={({ field }) => (
+                <FormItem className="flex items-center space-x-2 space-y-0">
+                  <FormControl>
+                    <Switch id="shrink" checked={field.value} onCheckedChange={field.onChange} />
+                  </FormControl>
+                  <Label htmlFor="shrink">{t("mainConfig.shrink")}</Label>
+                </FormItem>
+              )}
+            />
           </div>
         </CardContent>
       </Card>

web/src/i18n/en.json

@@ -36,6 +36,7 @@
     "shellClassName": "Shell ClassName",
     "shellMountType": "Shell Mount Type",
     "shellTool": "Shell Tool",
+    "shrink": "Shrink Bytecode",
     "urlPattern": "URL Pattern"
   },
   "optional": "(Optional)",

web/src/i18n/zh-CN.json

@@ -36,6 +36,7 @@
     "shellClassName": "内存马类名",
     "shellMountType": "内存马挂载类型",
     "shellTool": "内存马功能",
+    "shrink": "缩小字节码",
     "urlPattern": "请求路径"
   },
   "optional": "(可选)",

web/src/types/schema.ts

@@ -18,6 +18,7 @@ export const formSchema = z.object({
   headerValue: z.optional(z.string()),
   injectorClassName: z.optional(z.string()),
   packingMethod: z.string().min(1),
+  shrink: z.optional(z.boolean()),
 });
 
 export type FormSchema = z.infer<typeof formSchema>;

web/src/types/shell.ts

@@ -6,6 +6,7 @@ export interface ShellConfig {
   debug?: boolean;
   byPassJavaModule?: boolean;
   obfuscate?: boolean;
+  shrink?: boolean;
 }
 
 export interface ShellToolConfig {

web/src/utils/transformer.ts

@@ -9,6 +9,7 @@ export function transformToPostData(formValue: FormSchema) {
     debug: formValue.debug,
     targetJreVersion: formValue.targetJdkVersion,
     byPassJavaModule: formValue.bypassJavaModule,
+    shrink: formValue.shrink,
   };
   const shellToolConfig: ShellToolConfig = {
     shellClassName: formValue.shellClassName,