From 831ab8f805302e3ed92860fb7e6c87423e367a6d Mon Sep 17 00:00:00 2001
From: eyalkoren <41850454+eyalkoren@users.noreply.github.com>
Date: Tue, 23 Apr 2019 11:50:56 +0300
Subject: [PATCH] Fix Manifest version reading error to support jar:file
 protocol (#601)

---
 .../bci/bytebuddy/CustomElementMatchers.java  | 23 ++++++++++++++++---
 .../bytebuddy/CustomElementMatchersTest.java  | 18 +++++++++++++--
 2 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/apm-agent-core/src/main/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchers.java b/apm-agent-core/src/main/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchers.java
index 2d0c9da86d..ac20887f8c 100644
--- a/apm-agent-core/src/main/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchers.java
+++ b/apm-agent-core/src/main/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchers.java
@@ -23,13 +23,15 @@
 import com.blogspot.mydailyjava.weaklockfree.WeakConcurrentMap;
 import net.bytebuddy.description.NamedElement;
 import net.bytebuddy.description.method.MethodDescription;
-import net.bytebuddy.dynamic.ClassFileLocator;
 import net.bytebuddy.matcher.ElementMatcher;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.annotation.Nullable;
+import java.io.IOException;
+import java.net.JarURLConnection;
 import java.net.URL;
+import java.net.URLConnection;
 import java.security.CodeSource;
 import java.security.ProtectionDomain;
 import java.util.Collection;
@@ -135,14 +137,21 @@ public boolean matches(@Nullable ProtectionDomain protectionDomain) {
 
     private static @Nullable Version readImplementationVersionFromManifest(@Nullable ProtectionDomain protectionDomain) {
         Version version = null;
+        JarFile jarFile = null;
         try {
             if (protectionDomain != null) {
                 CodeSource codeSource = protectionDomain.getCodeSource();
                 if (codeSource != null) {
                     URL jarUrl = codeSource.getLocation();
                     if (jarUrl != null) {
-                        JarFile jar = new JarFile(jarUrl.getFile());
-                        Manifest manifest = jar.getManifest();
+                        // does not yet establish an actual connection
+                        URLConnection urlConnection = jarUrl.openConnection();
+                        if (urlConnection instanceof JarURLConnection) {
+                            jarFile = ((JarURLConnection) urlConnection).getJarFile();
+                        } else {
+                            jarFile = new JarFile(jarUrl.getFile());
+                        }
+                        Manifest manifest = jarFile.getManifest();
                         if (manifest != null) {
                             String implementationVersion = manifest.getMainAttributes().getValue("Implementation-Version");
                             if (implementationVersion != null) {
@@ -156,6 +165,14 @@ public boolean matches(@Nullable ProtectionDomain protectionDomain) {
             }
         } catch (Exception e) {
             logger.error("Cannot read implementation version based on ProtectionDomain " + protectionDomain, e);
+        } finally {
+            if (jarFile != null) {
+                try {
+                    jarFile.close();
+                } catch (IOException e) {
+                    logger.error("Error closing JarFile", e);
+                }
+            }
         }
         return version;
     }
diff --git a/apm-agent-core/src/test/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchersTest.java b/apm-agent-core/src/test/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchersTest.java
index 7c4b337a91..1d979358a9 100644
--- a/apm-agent-core/src/test/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchersTest.java
+++ b/apm-agent-core/src/test/java/co/elastic/apm/agent/bci/bytebuddy/CustomElementMatchersTest.java
@@ -23,6 +23,10 @@
 import org.apache.http.client.HttpClient;
 import org.junit.jupiter.api.Test;
 
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.security.CodeSigner;
+import java.security.CodeSource;
 import java.security.ProtectionDomain;
 import java.util.List;
 
@@ -50,9 +54,19 @@ void testClassLoaderCanLoadClass() {
     }
 
     @Test
-    void testSemVerLteMatcher() {
+    void testSemVerLteWithFileUrl() {
         // Relying on Apache httpclient-4.5.6.jar
-        ProtectionDomain protectionDomain = HttpClient.class.getProtectionDomain();
+        testSemVerLteMatcher(HttpClient.class.getProtectionDomain());
+    }
+
+    @Test
+    void testSemVerLteWithJarFileUrl() throws MalformedURLException {
+        URL originalUrl = HttpClient.class.getProtectionDomain().getCodeSource().getLocation();
+        URL jarFileUrl = new URL("jar:" + originalUrl.toString() + "!/");
+        testSemVerLteMatcher(new ProtectionDomain(new CodeSource(jarFileUrl, new CodeSigner[0]), null));
+    }
+
+    private void testSemVerLteMatcher(ProtectionDomain protectionDomain) {
         assertThat(implementationVersionLte("3").matches(protectionDomain)).isFalse();
         assertThat(implementationVersionLte("3.2").matches(protectionDomain)).isFalse();
         assertThat(implementationVersionLte("3.15.10").matches(protectionDomain)).isFalse();