1 /*
   2  * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classFileParser.hpp"
  27 #include "classfile/classFileStream.hpp"
  28 #include "classfile/classLoader.inline.hpp"
  29 #include "classfile/classLoaderExt.hpp"
  30 #include "classfile/classLoaderData.inline.hpp"
  31 #include "classfile/klassFactory.hpp"
  32 #include "classfile/modules.hpp"
  33 #include "classfile/sharedPathsMiscInfo.hpp"
  34 #include "classfile/systemDictionaryShared.hpp"
  35 #include "classfile/vmSymbols.hpp"
  36 #include "memory/allocation.inline.hpp"
  37 #include "memory/filemap.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "oops/instanceKlass.hpp"
  40 #include "oops/oop.inline.hpp"
  41 #include "oops/symbol.hpp"
  42 #include "runtime/arguments.hpp"
  43 #include "runtime/handles.inline.hpp"
  44 #include "runtime/java.hpp"
  45 #include "runtime/javaCalls.hpp"
  46 #include "runtime/os.hpp"
  47 #include "services/threadService.hpp"
  48 #include "utilities/stringUtils.hpp"
  49 
  50 jshort ClassLoaderExt::_app_class_paths_start_index = ClassLoaderExt::max_classpath_index;
  51 jshort ClassLoaderExt::_app_module_paths_start_index = ClassLoaderExt::max_classpath_index;
  52 jshort ClassLoaderExt::_max_used_path_index = 0;
  53 bool ClassLoaderExt::_has_app_classes = false;
  54 bool ClassLoaderExt::_has_platform_classes = false;
  55 
  56 void ClassLoaderExt::append_boot_classpath(ClassPathEntry* new_entry) {
  57   if (UseSharedSpaces) {
  58     warning("Sharing is only supported for boot loader classes because bootstrap classpath has been appended");
  59     FileMapInfo::current_info()->header()->set_has_platform_or_app_classes(false);
  60   }
  61   ClassLoader::add_to_boot_append_entries(new_entry);
  62 }
  63 
  64 void ClassLoaderExt::setup_app_search_path() {
  65   assert(DumpSharedSpaces || DynamicDumpSharedSpaces,
  66          "this function is only used at CDS dump time");
  67   _app_class_paths_start_index = ClassLoader::num_boot_classpath_entries();
  68   char* app_class_path = os::strdup(Arguments::get_appclasspath());
  69 
  70   if (strcmp(app_class_path, ".") == 0) {
  71     // This doesn't make any sense, even for AppCDS, so let's skip it. We
  72     // don't want to throw an error here because -cp "." is usually assigned
  73     // by the launcher when classpath is not specified.
  74     trace_class_path("app loader class path (skipped)=", app_class_path);
  75   } else {
  76     trace_class_path("app loader class path=", app_class_path);
  77     shared_paths_misc_info()->add_app_classpath(app_class_path);
  78     ClassLoader::setup_app_search_path(app_class_path);
  79   }
  80 }
  81 
  82 void ClassLoaderExt::process_module_table(ModuleEntryTable* met, TRAPS) {
  83   ResourceMark rm(THREAD);
  84   for (int i = 0; i < met->table_size(); i++) {
  85     for (ModuleEntry* m = met->bucket(i); m != NULL;) {
  86       char* path = m->location()->as_C_string();
  87       if (strncmp(path, "file:", 5) == 0) {
  88         path = ClassLoader::skip_uri_protocol(path);
  89         ClassLoader::setup_module_search_path(path, THREAD);
  90       }
  91       m = m->next();
  92     }
  93   }
  94 }
  95 void ClassLoaderExt::setup_module_paths(TRAPS) {
  96   assert(DumpSharedSpaces || DynamicDumpSharedSpaces,
  97          "this function is only used with CDS dump time");
  98   _app_module_paths_start_index = ClassLoader::num_boot_classpath_entries() +
  99                               ClassLoader::num_app_classpath_entries();
 100   Handle system_class_loader (THREAD, SystemDictionary::java_system_loader());
 101   ModuleEntryTable* met = Modules::get_module_entry_table(system_class_loader);
 102   process_module_table(met, THREAD);
 103 }
 104 
 105 char* ClassLoaderExt::read_manifest(ClassPathEntry* entry, jint *manifest_size, bool clean_text, TRAPS) {
 106   const char* name = "META-INF/MANIFEST.MF";
 107   char* manifest;
 108   jint size;
 109 
 110   assert(entry->is_jar_file(), "must be");
 111   manifest = (char*) ((ClassPathZipEntry*)entry )->open_entry(name, &size, true, CHECK_NULL);
 112 
 113   if (manifest == NULL) { // No Manifest
 114     *manifest_size = 0;
 115     return NULL;
 116   }
 117 
 118 
 119   if (clean_text) {
 120     // See http://docs.oracle.com/javase/6/docs/technotes/guides/jar/jar.html#JAR%20Manifest
 121     // (1): replace all CR/LF and CR with LF
 122     StringUtils::replace_no_expand(manifest, "\r\n", "\n");
 123 
 124     // (2) remove all new-line continuation (remove all "\n " substrings)
 125     StringUtils::replace_no_expand(manifest, "\n ", "");
 126   }
 127 
 128   *manifest_size = (jint)strlen(manifest);
 129   return manifest;
 130 }
 131 
 132 char* ClassLoaderExt::get_class_path_attr(const char* jar_path, char* manifest, jint manifest_size) {
 133   const char* tag = "Class-Path: ";
 134   const int tag_len = (int)strlen(tag);
 135   char* found = NULL;
 136   char* line_start = manifest;
 137   char* end = manifest + manifest_size;
 138 
 139   assert(*end == 0, "must be nul-terminated");
 140 
 141   while (line_start < end) {
 142     char* line_end = strchr(line_start, '\n');
 143     if (line_end == NULL) {
 144       // JAR spec require the manifest file to be terminated by a new line.
 145       break;
 146     }
 147     if (strncmp(tag, line_start, tag_len) == 0) {
 148       if (found != NULL) {
 149         // Same behavior as jdk/src/share/classes/java/util/jar/Attributes.java
 150         // If duplicated entries are found, the last one is used.
 151         tty->print_cr("Warning: Duplicate name in Manifest: %s.\n"
 152                       "Ensure that the manifest does not have duplicate entries, and\n"
 153                       "that blank lines separate individual sections in both your\n"
 154                       "manifest and in the META-INF/MANIFEST.MF entry in the jar file:\n%s\n", tag, jar_path);
 155       }
 156       found = line_start + tag_len;
 157       assert(found <= line_end, "sanity");
 158       *line_end = '\0';
 159     }
 160     line_start = line_end + 1;
 161   }
 162   return found;
 163 }
 164 
 165 void ClassLoaderExt::process_jar_manifest(ClassPathEntry* entry,
 166                                           bool check_for_duplicates) {
 167   Thread* THREAD = Thread::current();
 168   ResourceMark rm(THREAD);
 169   jint manifest_size;
 170   char* manifest = read_manifest(entry, &manifest_size, CHECK);
 171 
 172   if (manifest == NULL) {
 173     return;
 174   }
 175 
 176   if (strstr(manifest, "Extension-List:") != NULL) {
 177     vm_exit_during_cds_dumping(err_msg("-Xshare:dump does not support Extension-List in JAR manifest: %s", entry->name()));
 178   }
 179 
 180   char* cp_attr = get_class_path_attr(entry->name(), manifest, manifest_size);
 181 
 182   if (cp_attr != NULL && strlen(cp_attr) > 0) {
 183     trace_class_path("found Class-Path: ", cp_attr);
 184 
 185     char sep = os::file_separator()[0];
 186     const char* dir_name = entry->name();
 187     const char* dir_tail = strrchr(dir_name, sep);
 188     int dir_len;
 189     if (dir_tail == NULL) {
 190       dir_len = 0;
 191     } else {
 192       dir_len = dir_tail - dir_name + 1;
 193     }
 194 
 195     // Split the cp_attr by spaces, and add each file
 196     char* file_start = cp_attr;
 197     char* end = file_start + strlen(file_start);
 198 
 199     while (file_start < end) {
 200       char* file_end = strchr(file_start, ' ');
 201       if (file_end != NULL) {
 202         *file_end = 0;
 203         file_end += 1;
 204       } else {
 205         file_end = end;
 206       }
 207 
 208       size_t name_len = strlen(file_start);
 209       if (name_len > 0) {
 210         ResourceMark rm(THREAD);
 211         size_t libname_len = dir_len + name_len;
 212         char* libname = NEW_RESOURCE_ARRAY(char, libname_len + 1);
 213         int n = os::snprintf(libname, libname_len + 1, "%.*s%s", dir_len, dir_name, file_start);
 214         assert((size_t)n == libname_len, "Unexpected number of characters in string");
 215         trace_class_path("library = ", libname);
 216         ClassLoader::update_class_path_entry_list(libname, true, false);
 217       }
 218 
 219       file_start = file_end;
 220     }
 221   }
 222 }
 223 
 224 void ClassLoaderExt::setup_search_paths() {
 225   shared_paths_misc_info()->record_app_offset();
 226   ClassLoaderExt::setup_app_search_path();
 227 }
 228 
 229 void ClassLoaderExt::record_result(const s2 classpath_index,
 230                                    InstanceKlass* result,
 231                                    TRAPS) {
 232   assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "Sanity");
 233 
 234   // We need to remember where the class comes from during dumping.
 235   oop loader = result->class_loader();
 236   s2 classloader_type = ClassLoader::BOOT_LOADER;
 237   if (SystemDictionary::is_system_class_loader(loader)) {
 238     classloader_type = ClassLoader::APP_LOADER;
 239     ClassLoaderExt::set_has_app_classes();
 240   } else if (SystemDictionary::is_platform_class_loader(loader)) {
 241     classloader_type = ClassLoader::PLATFORM_LOADER;
 242     ClassLoaderExt::set_has_platform_classes();
 243   }
 244   if (classpath_index > ClassLoaderExt::max_used_path_index()) {
 245     ClassLoaderExt::set_max_used_path_index(classpath_index);
 246   }
 247   result->set_shared_classpath_index(classpath_index);
 248   result->set_class_loader_type(classloader_type);
 249 }
 250 
 251 void ClassLoaderExt::finalize_shared_paths_misc_info() {
 252   if (!_has_app_classes) {
 253     shared_paths_misc_info()->pop_app();
 254   }
 255 }
 256 
 257 // Load the class of the given name from the location given by path. The path is specified by
 258 // the "source:" in the class list file (see classListParser.cpp), and can be a directory or
 259 // a JAR file.
 260 InstanceKlass* ClassLoaderExt::load_class(Symbol* name, const char* path, TRAPS) {
 261   assert(name != NULL, "invariant");
 262   assert(DumpSharedSpaces, "this function is only used with -Xshare:dump");
 263   ResourceMark rm(THREAD);
 264   const char* class_name = name->as_C_string();
 265 
 266   const char* file_name = file_name_for_class_name(class_name,
 267                                                    name->utf8_length());
 268   assert(file_name != NULL, "invariant");
 269 
 270   // Lookup stream for parsing .class file
 271   ClassFileStream* stream = NULL;
 272   ClassPathEntry* e = find_classpath_entry_from_cache(path, CHECK_NULL);
 273   if (e == NULL) {
 274     return NULL;
 275   }
 276   {
 277     PerfClassTraceTime vmtimer(perf_sys_class_lookup_time(),
 278                                ((JavaThread*) THREAD)->get_thread_stat()->perf_timers_addr(),
 279                                PerfClassTraceTime::CLASS_LOAD);
 280     stream = e->open_stream(file_name, CHECK_NULL);
 281   }
 282 
 283   if (NULL == stream) {
 284     tty->print_cr("Preload Warning: Cannot find %s", class_name);
 285     return NULL;
 286   }
 287 
 288   assert(stream != NULL, "invariant");
 289   stream->set_verify(true);
 290 
 291   ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
 292   Handle protection_domain;
 293 
 294   InstanceKlass* result = KlassFactory::create_from_stream(stream,
 295                                                            name,
 296                                                            loader_data,
 297                                                            protection_domain,
 298                                                            NULL, // unsafe_anonymous_host
 299                                                            NULL, // cp_patches
 300                                                            THREAD);
 301 
 302   if (HAS_PENDING_EXCEPTION) {
 303     tty->print_cr("Preload Error: Failed to load %s", class_name);
 304     return NULL;
 305   }
 306   return result;
 307 }
 308 
 309 struct CachedClassPathEntry {
 310   const char* _path;
 311   ClassPathEntry* _entry;
 312 };
 313 
 314 static GrowableArray<CachedClassPathEntry>* cached_path_entries = NULL;
 315 
 316 ClassPathEntry* ClassLoaderExt::find_classpath_entry_from_cache(const char* path, TRAPS) {
 317   // This is called from dump time so it's single threaded and there's no need for a lock.
 318   assert(DumpSharedSpaces, "this function is only used with -Xshare:dump");
 319   if (cached_path_entries == NULL) {
 320     cached_path_entries = new (ResourceObj::C_HEAP, mtClass) GrowableArray<CachedClassPathEntry>(20, /*c heap*/ true);
 321   }
 322   CachedClassPathEntry ccpe;
 323   for (int i=0; i<cached_path_entries->length(); i++) {
 324     ccpe = cached_path_entries->at(i);
 325     if (strcmp(ccpe._path, path) == 0) {
 326       if (i != 0) {
 327         // Put recent entries at the beginning to speed up searches.
 328         cached_path_entries->remove_at(i);
 329         cached_path_entries->insert_before(0, ccpe);
 330       }
 331       return ccpe._entry;
 332     }
 333   }
 334 
 335   struct stat st;
 336   if (os::stat(path, &st) != 0) {
 337     // File or directory not found
 338     return NULL;
 339   }
 340   ClassPathEntry* new_entry = NULL;
 341 
 342   new_entry = create_class_path_entry(path, &st, false, false, CHECK_NULL);
 343   if (new_entry == NULL) {
 344     return NULL;
 345   }
 346   ccpe._path = strdup(path);
 347   ccpe._entry = new_entry;
 348   cached_path_entries->insert_before(0, ccpe);
 349   return new_entry;
 350 }