1 /* 2 * Copyright (c) 1997, 2012, 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/javaClasses.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/vmSymbols.hpp" 29 #include "memory/oopFactory.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "memory/universe.inline.hpp" 32 #include "oops/instanceKlass.hpp" 33 #include "oops/method.hpp" 34 #include "oops/oop.inline.hpp" 35 #include "oops/symbol.hpp" 36 #include "prims/jvm_misc.hpp" 37 #include "prims/nativeLookup.hpp" 38 #include "runtime/arguments.hpp" 39 #include "runtime/handles.inline.hpp" 40 #include "runtime/javaCalls.hpp" 41 #include "runtime/sharedRuntime.hpp" 42 #include "runtime/signature.hpp" 43 #include "utilities/macros.hpp" 44 #ifdef TARGET_OS_FAMILY_linux 45 # include "os_linux.inline.hpp" 46 #endif 47 #ifdef TARGET_OS_FAMILY_solaris 48 # include "os_solaris.inline.hpp" 49 #endif 50 #ifdef TARGET_OS_FAMILY_windows 51 # include "os_windows.inline.hpp" 52 #endif 53 #ifdef TARGET_OS_FAMILY_bsd 54 # include "os_bsd.inline.hpp" 55 #endif 56 57 58 static void mangle_name_on(outputStream* st, Symbol* name, int begin, int end) { 59 char* bytes = (char*)name->bytes() + begin; 60 char* end_bytes = (char*)name->bytes() + end; 61 while (bytes < end_bytes) { 62 jchar c; 63 bytes = UTF8::next(bytes, &c); 64 if (c <= 0x7f && isalnum(c)) { 65 st->put((char) c); 66 } else { 67 if (c == '_') st->print("_1"); 68 else if (c == '/') st->print("_"); 69 else if (c == ';') st->print("_2"); 70 else if (c == '[') st->print("_3"); 71 else st->print("_%.5x", c); 72 } 73 } 74 } 75 76 77 static void mangle_name_on(outputStream* st, Symbol* name) { 78 mangle_name_on(st, name, 0, name->utf8_length()); 79 } 80 81 82 char* NativeLookup::pure_jni_name(methodHandle method) { 83 stringStream st; 84 // Prefix 85 st.print("Java_"); 86 // Klass name 87 mangle_name_on(&st, method->klass_name()); 88 st.print("_"); 89 // Method name 90 mangle_name_on(&st, method->name()); 91 return st.as_string(); 92 } 93 94 95 char* NativeLookup::critical_jni_name(methodHandle method) { 96 stringStream st; 97 // Prefix 98 st.print("JavaCritical_"); 99 // Klass name 100 mangle_name_on(&st, method->klass_name()); 101 st.print("_"); 102 // Method name 103 mangle_name_on(&st, method->name()); 104 return st.as_string(); 105 } 106 107 108 char* NativeLookup::long_jni_name(methodHandle method) { 109 // Signature ignore the wrapping parenteses and the trailing return type 110 stringStream st; 111 Symbol* signature = method->signature(); 112 st.print("__"); 113 // find ')' 114 int end; 115 for (end = 0; end < signature->utf8_length() && signature->byte_at(end) != ')'; end++); 116 // skip first '(' 117 mangle_name_on(&st, signature, 1, end); 118 return st.as_string(); 119 } 120 121 extern "C" { 122 void JNICALL JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls); 123 void JNICALL JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass unsafecls); 124 void JNICALL JVM_RegisterPerfMethods(JNIEnv *env, jclass perfclass); 125 void JNICALL JVM_RegisterWhiteBoxMethods(JNIEnv *env, jclass wbclass); 126 } 127 128 #define CC (char*) /* cast a literal from (const char*) */ 129 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f) 130 131 static JNINativeMethod lookup_special_native_methods[] = { 132 // Next two functions only exist for compatibility with 1.3.1 and earlier. 133 { CC"Java_java_io_ObjectOutputStream_getPrimitiveFieldValues", NULL, FN_PTR(JVM_GetPrimitiveFieldValues) }, // intercept ObjectOutputStream getPrimitiveFieldValues for faster serialization 134 { CC"Java_java_io_ObjectInputStream_setPrimitiveFieldValues", NULL, FN_PTR(JVM_SetPrimitiveFieldValues) }, // intercept ObjectInputStream setPrimitiveFieldValues for faster serialization 135 136 { CC"Java_sun_misc_Unsafe_registerNatives", NULL, FN_PTR(JVM_RegisterUnsafeMethods) }, 137 { CC"Java_java_lang_invoke_MethodHandleNatives_registerNatives", NULL, FN_PTR(JVM_RegisterMethodHandleMethods) }, 138 { CC"Java_sun_misc_Perf_registerNatives", NULL, FN_PTR(JVM_RegisterPerfMethods) }, 139 { CC"Java_sun_hotspot_WhiteBox_registerNatives", NULL, FN_PTR(JVM_RegisterWhiteBoxMethods) }, 140 }; 141 142 static address lookup_special_native(char* jni_name) { 143 int i = !JDK_Version::is_gte_jdk14x_version() ? 0 : 2; // see comment in lookup_special_native_methods 144 int count = sizeof(lookup_special_native_methods) / sizeof(JNINativeMethod); 145 for (; i < count; i++) { 146 // NB: To ignore the jni prefix and jni postfix strstr is used matching. 147 if (strstr(jni_name, lookup_special_native_methods[i].name) != NULL) { 148 return CAST_FROM_FN_PTR(address, lookup_special_native_methods[i].fnPtr); 149 } 150 } 151 return NULL; 152 } 153 154 address NativeLookup::lookup_style(methodHandle method, char* pure_name, const char* long_name, int args_size, bool os_style, bool& in_base_library, TRAPS) { 155 address entry; 156 // Compute complete JNI name for style 157 stringStream st; 158 if (os_style) os::print_jni_name_prefix_on(&st, args_size); 159 st.print_raw(pure_name); 160 st.print_raw(long_name); 161 if (os_style) os::print_jni_name_suffix_on(&st, args_size); 162 char* jni_name = st.as_string(); 163 164 // If the loader is null we have a system class, so we attempt a lookup in 165 // the native Java library. This takes care of any bootstrapping problems. 166 // Note: It is critical for bootstrapping that Java_java_lang_ClassLoader_00024NativeLibrary_find 167 // gets found the first time around - otherwise an infinite loop can occure. This is 168 // another VM/library dependency 169 Handle loader(THREAD, method->method_holder()->class_loader()); 170 if (loader.is_null()) { 171 entry = lookup_special_native(jni_name); 172 if (entry == NULL) { 173 entry = (address) os::dll_lookup(os::native_java_library(), jni_name); 174 } 175 if (entry != NULL) { 176 in_base_library = true; 177 return entry; 178 } 179 } 180 181 // Otherwise call static method findNative in ClassLoader 182 KlassHandle klass (THREAD, SystemDictionary::ClassLoader_klass()); 183 Handle name_arg = java_lang_String::create_from_str(jni_name, CHECK_NULL); 184 185 JavaValue result(T_LONG); 186 JavaCalls::call_static(&result, 187 klass, 188 vmSymbols::findNative_name(), 189 vmSymbols::classloader_string_long_signature(), 190 // Arguments 191 loader, 192 name_arg, 193 CHECK_NULL); 194 entry = (address) (intptr_t) result.get_jlong(); 195 196 if (entry == NULL) { 197 // findNative didn't find it, if there are any agent libraries look in them 198 AgentLibrary* agent; 199 for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) { 200 entry = (address) os::dll_lookup(agent->os_lib(), jni_name); 201 if (entry != NULL) { 202 return entry; 203 } 204 } 205 } 206 207 return entry; 208 } 209 210 211 address NativeLookup::lookup_critical_style(methodHandle method, char* pure_name, const char* long_name, int args_size, bool os_style) { 212 if (!method->has_native_function()) { 213 return NULL; 214 } 215 216 address current_entry = method->native_function(); 217 218 char dll_name[JVM_MAXPATHLEN]; 219 int offset; 220 if (os::dll_address_to_library_name(current_entry, dll_name, sizeof(dll_name), &offset)) { 221 char ebuf[32]; 222 void* dll = os::dll_load(dll_name, ebuf, sizeof(ebuf)); 223 if (dll != NULL) { 224 // Compute complete JNI name for style 225 stringStream st; 226 if (os_style) os::print_jni_name_prefix_on(&st, args_size); 227 st.print_raw(pure_name); 228 st.print_raw(long_name); 229 if (os_style) os::print_jni_name_suffix_on(&st, args_size); 230 char* jni_name = st.as_string(); 231 return (address)os::dll_lookup(dll, jni_name); 232 } 233 } 234 235 return NULL; 236 } 237 238 239 // Check all the formats of native implementation name to see if there is one 240 // for the specified method. 241 address NativeLookup::lookup_entry(methodHandle method, bool& in_base_library, TRAPS) { 242 address entry = NULL; 243 in_base_library = false; 244 // Compute pure name 245 char* pure_name = pure_jni_name(method); 246 247 // Compute argument size 248 int args_size = 1 // JNIEnv 249 + (method->is_static() ? 1 : 0) // class for static methods 250 + method->size_of_parameters(); // actual parameters 251 252 253 // 1) Try JNI short style 254 entry = lookup_style(method, pure_name, "", args_size, true, in_base_library, CHECK_NULL); 255 if (entry != NULL) return entry; 256 257 // Compute long name 258 char* long_name = long_jni_name(method); 259 260 // 2) Try JNI long style 261 entry = lookup_style(method, pure_name, long_name, args_size, true, in_base_library, CHECK_NULL); 262 if (entry != NULL) return entry; 263 264 // 3) Try JNI short style without os prefix/suffix 265 entry = lookup_style(method, pure_name, "", args_size, false, in_base_library, CHECK_NULL); 266 if (entry != NULL) return entry; 267 268 // 4) Try JNI long style without os prefix/suffix 269 entry = lookup_style(method, pure_name, long_name, args_size, false, in_base_library, CHECK_NULL); 270 271 return entry; // NULL indicates not found 272 } 273 274 // Check all the formats of native implementation name to see if there is one 275 // for the specified method. 276 address NativeLookup::lookup_critical_entry(methodHandle method) { 277 if (!CriticalJNINatives) return NULL; 278 279 if (method->is_synchronized() || 280 !method->is_static()) { 281 // Only static non-synchronized methods are allowed 282 return NULL; 283 } 284 285 ResourceMark rm; 286 address entry = NULL; 287 288 Symbol* signature = method->signature(); 289 for (int end = 0; end < signature->utf8_length(); end++) { 290 if (signature->byte_at(end) == 'L') { 291 // Don't allow object types 292 return NULL; 293 } 294 } 295 296 // Compute critical name 297 char* critical_name = critical_jni_name(method); 298 299 // Compute argument size 300 int args_size = 1 // JNIEnv 301 + (method->is_static() ? 1 : 0) // class for static methods 302 + method->size_of_parameters(); // actual parameters 303 304 305 // 1) Try JNI short style 306 entry = lookup_critical_style(method, critical_name, "", args_size, true); 307 if (entry != NULL) return entry; 308 309 // Compute long name 310 char* long_name = long_jni_name(method); 311 312 // 2) Try JNI long style 313 entry = lookup_critical_style(method, critical_name, long_name, args_size, true); 314 if (entry != NULL) return entry; 315 316 // 3) Try JNI short style without os prefix/suffix 317 entry = lookup_critical_style(method, critical_name, "", args_size, false); 318 if (entry != NULL) return entry; 319 320 // 4) Try JNI long style without os prefix/suffix 321 entry = lookup_critical_style(method, critical_name, long_name, args_size, false); 322 323 return entry; // NULL indicates not found 324 } 325 326 // Check if there are any JVM TI prefixes which have been applied to the native method name. 327 // If any are found, remove them before attemping the look up of the 328 // native implementation again. 329 // See SetNativeMethodPrefix in the JVM TI Spec for more details. 330 address NativeLookup::lookup_entry_prefixed(methodHandle method, bool& in_base_library, TRAPS) { 331 #if INCLUDE_JVMTI 332 ResourceMark rm(THREAD); 333 334 int prefix_count; 335 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count); 336 char* in_name = method->name()->as_C_string(); 337 char* wrapper_name = in_name; 338 // last applied prefix will be first -- go backwards 339 for (int i = prefix_count-1; i >= 0; i--) { 340 char* prefix = prefixes[i]; 341 size_t prefix_len = strlen(prefix); 342 if (strncmp(prefix, wrapper_name, prefix_len) == 0) { 343 // has this prefix remove it 344 wrapper_name += prefix_len; 345 } 346 } 347 if (wrapper_name != in_name) { 348 // we have a name for a wrapping method 349 int wrapper_name_len = (int)strlen(wrapper_name); 350 TempNewSymbol wrapper_symbol = SymbolTable::probe(wrapper_name, wrapper_name_len); 351 if (wrapper_symbol != NULL) { 352 KlassHandle kh(method->method_holder()); 353 Method* wrapper_method = kh()->lookup_method(wrapper_symbol, 354 method->signature()); 355 if (wrapper_method != NULL && !wrapper_method->is_native()) { 356 // we found a wrapper method, use its native entry 357 method->set_is_prefixed_native(); 358 return lookup_entry(wrapper_method, in_base_library, THREAD); 359 } 360 } 361 } 362 #endif // INCLUDE_JVMTI 363 return NULL; 364 } 365 366 address NativeLookup::lookup_base(methodHandle method, bool& in_base_library, TRAPS) { 367 address entry = NULL; 368 ResourceMark rm(THREAD); 369 370 entry = lookup_entry(method, in_base_library, THREAD); 371 if (entry != NULL) return entry; 372 373 // standard native method resolution has failed. Check if there are any 374 // JVM TI prefixes which have been applied to the native method name. 375 entry = lookup_entry_prefixed(method, in_base_library, THREAD); 376 if (entry != NULL) return entry; 377 378 // Native function not found, throw UnsatisfiedLinkError 379 THROW_MSG_0(vmSymbols::java_lang_UnsatisfiedLinkError(), 380 method->name_and_sig_as_C_string()); 381 } 382 383 384 address NativeLookup::lookup(methodHandle method, bool& in_base_library, TRAPS) { 385 if (!method->has_native_function()) { 386 address entry = lookup_base(method, in_base_library, CHECK_NULL); 387 method->set_native_function(entry, 388 Method::native_bind_event_is_interesting); 389 // -verbose:jni printing 390 if (PrintJNIResolving) { 391 ResourceMark rm(THREAD); 392 tty->print_cr("[Dynamic-linking native method %s.%s ... JNI]", 393 method->method_holder()->external_name(), 394 method->name()->as_C_string()); 395 } 396 } 397 return method->native_function(); 398 } 399 400 address NativeLookup::base_library_lookup(const char* class_name, const char* method_name, const char* signature) { 401 EXCEPTION_MARK; 402 bool in_base_library = true; // SharedRuntime inits some math methods. 403 TempNewSymbol c_name = SymbolTable::new_symbol(class_name, CATCH); 404 TempNewSymbol m_name = SymbolTable::new_symbol(method_name, CATCH); 405 TempNewSymbol s_name = SymbolTable::new_symbol(signature, CATCH); 406 407 // Find the class 408 Klass* k = SystemDictionary::resolve_or_fail(c_name, true, CATCH); 409 instanceKlassHandle klass (THREAD, k); 410 411 // Find method and invoke standard lookup 412 methodHandle method (THREAD, 413 klass->uncached_lookup_method(m_name, s_name)); 414 address result = lookup(method, in_base_library, CATCH); 415 assert(in_base_library, "must be in basic library"); 416 guarantee(result != NULL, "must be non NULL"); 417 return result; 418 }