1 /* 2 * Copyright (c) 2003, 2018, 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/symbolTable.hpp" 27 #include "classfile/systemDictionaryShared.hpp" 28 #include "classfile/verificationType.hpp" 29 #include "classfile/verifier.hpp" 30 #include "logging/log.hpp" 31 #include "runtime/handles.inline.hpp" 32 33 VerificationType VerificationType::from_tag(u1 tag) { 34 switch (tag) { 35 case ITEM_Top: return bogus_type(); 36 case ITEM_Integer: return integer_type(); 37 case ITEM_Float: return float_type(); 38 case ITEM_Double: return double_type(); 39 case ITEM_Long: return long_type(); 40 case ITEM_Null: return null_type(); 41 default: 42 ShouldNotReachHere(); 43 return bogus_type(); 44 } 45 } 46 47 bool VerificationType::resolve_and_check_assignability(InstanceKlass* klass, Symbol* name, 48 Symbol* from_name, bool from_field_is_protected, bool from_is_array, bool from_is_object, TRAPS) { 49 HandleMark hm(THREAD); 50 Klass* this_class = SystemDictionary::resolve_or_fail( 51 name, Handle(THREAD, klass->class_loader()), 52 Handle(THREAD, klass->protection_domain()), true, CHECK_false); 53 klass->class_loader_data()->record_dependency(this_class); 54 if (log_is_enabled(Debug, class, resolve)) { 55 Verifier::trace_class_resolution(this_class, klass); 56 } 57 58 if (this_class->access_flags().is_value_type()) return false; 59 if (this_class->is_interface() && (!from_field_is_protected || 60 from_name != vmSymbols::java_lang_Object())) { 61 // If we are not trying to access a protected field or method in 62 // java.lang.Object then, for arrays, we only allow assignability 63 // to interfaces java.lang.Cloneable and java.io.Serializable. 64 // Otherwise, we treat interfaces as java.lang.Object. 65 return !from_is_array || 66 this_class == SystemDictionary::Cloneable_klass() || 67 this_class == SystemDictionary::Serializable_klass(); 68 } else if (from_is_object) { 69 Klass* from_class = SystemDictionary::resolve_or_fail( 70 from_name, Handle(THREAD, klass->class_loader()), 71 Handle(THREAD, klass->protection_domain()), true, CHECK_false); 72 klass->class_loader_data()->record_dependency(from_class); 73 if (log_is_enabled(Debug, class, resolve)) { 74 Verifier::trace_class_resolution(from_class, klass); 75 } 76 return InstanceKlass::cast(from_class)->is_subclass_of(this_class); 77 } 78 79 return false; 80 } 81 82 bool VerificationType::is_reference_assignable_from( 83 const VerificationType& from, ClassVerifier* context, 84 bool from_field_is_protected, TRAPS) const { 85 InstanceKlass* klass = context->current_class(); 86 if (from.is_null()) { 87 // null is assignable to any reference 88 return true; 89 } else if (is_null()) { 90 return false; 91 } else if (name() == from.name()) { 92 return true; 93 } else if (is_object()) { 94 // We need check the class hierarchy to check assignability 95 if (name() == vmSymbols::java_lang_Object()) { 96 // any object or array is assignable to java.lang.Object 97 return true; 98 } 99 100 if (DumpSharedSpaces && SystemDictionaryShared::add_verification_constraint(klass, 101 name(), from.name(), from_field_is_protected, from.is_array(), 102 from.is_object())) { 103 // If add_verification_constraint() returns true, the resolution/check should be 104 // delayed until runtime. 105 return true; 106 } 107 108 return resolve_and_check_assignability(klass, name(), from.name(), 109 from_field_is_protected, from.is_array(), from.is_object(), THREAD); 110 } else if (is_array() && from.is_array()) { 111 VerificationType comp_this = get_component(context, CHECK_false); 112 VerificationType comp_from = from.get_component(context, CHECK_false); 113 114 if (comp_from.is_valuetype() && !comp_this.is_null() && comp_this.is_reference()) { 115 // An array of value types is not assignable to an array of java.lang.Objects. 116 if (comp_this.name() == vmSymbols::java_lang_Object()) { 117 return false; 118 } 119 120 // Need to load 'comp_this' to see if it is an interface. 121 InstanceKlass* klass = context->current_class(); 122 { 123 HandleMark hm(THREAD); 124 Klass* comp_this_class = SystemDictionary::resolve_or_fail( 125 comp_this.name(), Handle(THREAD, klass->class_loader()), 126 Handle(THREAD, klass->protection_domain()), true, CHECK_false); 127 klass->class_loader_data()->record_dependency(comp_this_class); 128 if (log_is_enabled(Debug, class, resolve)) { 129 Verifier::trace_class_resolution(comp_this_class, klass); 130 } 131 // An array of value types is not assignable to an array of interface types. 132 if (comp_this_class->is_interface()) { 133 return false; 134 } 135 } 136 } 137 138 if (!comp_this.is_bogus() && !comp_from.is_bogus()) { 139 return comp_this.is_component_assignable_from(comp_from, context, 140 from_field_is_protected, THREAD); 141 } 142 } 143 return false; 144 } 145 146 bool VerificationType::is_valuetype_assignable_from(const VerificationType& from) const { 147 // Check that 'from' is not null, is a value type, and is the same value type. 148 assert(is_valuetype(), "called with a non-valuetype type"); 149 assert(!is_null(), "valuetype is not null"); 150 assert(name() != vmSymbols::java_lang_Object(), "java.lang.Object is a value type?"); 151 return (!from.is_null() && from.is_valuetype() && name() == from.name()); 152 } 153 154 bool VerificationType::is_ref_assignable_from_value_type(const VerificationType& from, ClassVerifier* context, TRAPS) const { 155 assert(!from.is_null(), "Value type should not be null"); 156 if (!is_null() && (name()->is_same_fundamental_type(from.name()) || 157 name() == vmSymbols::java_lang_Object())) { 158 return true; 159 } 160 161 // Need to load 'this' to see if it is an interface. 162 InstanceKlass* klass = context->current_class(); 163 { 164 HandleMark hm(THREAD); 165 Klass* this_class = SystemDictionary::resolve_or_fail( 166 name(), Handle(THREAD, klass->class_loader()), 167 Handle(THREAD, klass->protection_domain()), true, CHECK_false); 168 klass->class_loader_data()->record_dependency(this_class); 169 if (log_is_enabled(Debug, class, resolve)) { 170 Verifier::trace_class_resolution(this_class, klass); 171 } 172 return (this_class->is_interface()); 173 } 174 } 175 176 VerificationType VerificationType::get_component(ClassVerifier *context, TRAPS) const { 177 assert(is_array() && name()->utf8_length() >= 2, "Must be a valid array"); 178 Symbol* component; 179 switch (name()->char_at(1)) { 180 case 'Z': return VerificationType(Boolean); 181 case 'B': return VerificationType(Byte); 182 case 'C': return VerificationType(Char); 183 case 'S': return VerificationType(Short); 184 case 'I': return VerificationType(Integer); 185 case 'J': return VerificationType(Long); 186 case 'F': return VerificationType(Float); 187 case 'D': return VerificationType(Double); 188 case '[': 189 component = context->create_temporary_symbol( 190 name(), 1, name()->utf8_length(), 191 CHECK_(VerificationType::bogus_type())); 192 return VerificationType::reference_type(component); 193 case 'L': 194 component = context->create_temporary_symbol( 195 name(), 2, name()->utf8_length() - 1, 196 CHECK_(VerificationType::bogus_type())); 197 return VerificationType::reference_type(component); 198 case 'Q': 199 component = context->create_temporary_symbol( 200 name(), 2, name()->utf8_length() - 1, 201 CHECK_(VerificationType::bogus_type())); 202 return VerificationType::valuetype_type(component); 203 default: 204 // Met an invalid type signature, e.g. [X 205 return VerificationType::bogus_type(); 206 } 207 } 208 209 void VerificationType::print_on(outputStream* st) const { 210 switch (_u._data) { 211 case Bogus: st->print("top"); break; 212 case Category1: st->print("category1"); break; 213 case Category2: st->print("category2"); break; 214 case Category2_2nd: st->print("category2_2nd"); break; 215 case Boolean: st->print("boolean"); break; 216 case Byte: st->print("byte"); break; 217 case Short: st->print("short"); break; 218 case Char: st->print("char"); break; 219 case Integer: st->print("integer"); break; 220 case Float: st->print("float"); break; 221 case Long: st->print("long"); break; 222 case Double: st->print("double"); break; 223 case Long_2nd: st->print("long_2nd"); break; 224 case Double_2nd: st->print("double_2nd"); break; 225 case Null: st->print("null"); break; 226 case ReferenceQuery: st->print("reference type"); break; 227 case ValueTypeQuery: st->print("value type"); break; 228 case NonScalarQuery: st->print("reference or value type"); break; 229 case Category1Query: st->print("category1 type"); break; 230 case Category2Query: st->print("category2 type"); break; 231 case Category2_2ndQuery: st->print("category2_2nd type"); break; 232 default: 233 if (is_uninitialized_this()) { 234 st->print("uninitializedThis"); 235 } else if (is_uninitialized()) { 236 st->print("uninitialized %d", bci()); 237 } else if (is_valuetype()) { 238 name()->print_Qvalue_on(st); 239 } else { 240 if (name() != NULL) { 241 name()->print_value_on(st); 242 } else { 243 st->print_cr("NULL"); 244 } 245 } 246 } 247 }