1 /*
   2  * Copyright (c) 1994, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 /*-
  27  *      Implementation of class Class
  28  *
  29  *      former threadruntime.c, Sun Sep 22 12:09:39 1991
  30  */
  31 
  32 #include <string.h>
  33 #include <stdlib.h>
  34 
  35 #include "jni.h"
  36 #include "jni_util.h"
  37 #include "jvm.h"
  38 #include "check_classname.h"
  39 #include "java_lang_Class.h"
  40 
  41 /* defined in libverify.so/verify.dll (src file common/check_format.c) */
  42 extern jboolean VerifyClassname(char *utf_name, jboolean arrayAllowed);
  43 extern jboolean VerifyFixClassname(char *utf_name);
  44 
  45 #define OBJ "Ljava/lang/Object;"
  46 #define CLS "Ljava/lang/Class;"
  47 #define CPL "Ljdk/internal/reflect/ConstantPool;"
  48 #define STR "Ljava/lang/String;"
  49 #define FLD "Ljava/lang/reflect/Field;"
  50 #define MHD "Ljava/lang/reflect/Method;"
  51 #define CTR "Ljava/lang/reflect/Constructor;"
  52 #define PD  "Ljava/security/ProtectionDomain;"
  53 #define BA  "[B"
  54 #define RC  "Ljava/lang/reflect/RecordComponent;"
  55 
  56 static JNINativeMethod methods[] = {
  57     {"initClassName",    "()" STR,          (void *)&JVM_InitClassName},
  58     {"getSuperclass",    "()" CLS,          NULL},
  59     {"getInterfaces0",   "()[" CLS,         (void *)&JVM_GetClassInterfaces},
  60     {"isInterface",      "()Z",             (void *)&JVM_IsInterface},
  61     {"getSigners",       "()[" OBJ,         (void *)&JVM_GetClassSigners},
  62     {"setSigners",       "([" OBJ ")V",     (void *)&JVM_SetClassSigners},
  63     {"isArray",          "()Z",             (void *)&JVM_IsArrayClass},
  64     {"isHidden",         "()Z",             (void *)&JVM_IsHiddenClass},
  65     {"isPrimitive",      "()Z",             (void *)&JVM_IsPrimitiveClass},
  66     {"getModifiers",     "()I",             (void *)&JVM_GetClassModifiers},
  67     {"getDeclaredFields0","(Z)[" FLD,       (void *)&JVM_GetClassDeclaredFields},
  68     {"getDeclaredMethods0","(Z)[" MHD,      (void *)&JVM_GetClassDeclaredMethods},
  69     {"getDeclaredConstructors0","(Z)[" CTR, (void *)&JVM_GetClassDeclaredConstructors},
  70     {"getProtectionDomain0", "()" PD,       (void *)&JVM_GetProtectionDomain},
  71     {"getDeclaredClasses0",  "()[" CLS,     (void *)&JVM_GetDeclaredClasses},
  72     {"getDeclaringClass0",   "()" CLS,      (void *)&JVM_GetDeclaringClass},
  73     {"getSimpleBinaryName0", "()" STR,      (void *)&JVM_GetSimpleBinaryName},
  74     {"getGenericSignature0", "()" STR,      (void *)&JVM_GetClassSignature},
  75     {"getRawAnnotations",      "()" BA,     (void *)&JVM_GetClassAnnotations},
  76     {"getConstantPool",     "()" CPL,       (void *)&JVM_GetClassConstantPool},
  77     {"desiredAssertionStatus0","("CLS")Z",  (void *)&JVM_DesiredAssertionStatus},
  78     {"getEnclosingMethod0", "()[" OBJ,      (void *)&JVM_GetEnclosingMethodInfo},
  79     {"getRawTypeAnnotations", "()" BA,      (void *)&JVM_GetClassTypeAnnotations},
  80     {"getNestHost0",         "()" CLS,      (void *)&JVM_GetNestHost},
  81     {"getNestMembers0",      "()[" CLS,     (void *)&JVM_GetNestMembers},
  82     {"getRecordComponents0", "()[" RC,      (void *)&JVM_GetRecordComponents},
  83     {"isRecord0",            "()Z",         (void *)&JVM_IsRecord},
  84 };
  85 
  86 #undef OBJ
  87 #undef CLS
  88 #undef STR
  89 #undef FLD
  90 #undef MHD
  91 #undef CTR
  92 #undef PD
  93 
  94 JNIEXPORT void JNICALL
  95 Java_java_lang_Class_registerNatives(JNIEnv *env, jclass cls)
  96 {
  97     methods[1].fnPtr = (void *)(*env)->GetSuperclass;
  98     (*env)->RegisterNatives(env, cls, methods,
  99                             sizeof(methods)/sizeof(JNINativeMethod));
 100 }
 101 
 102 JNIEXPORT jclass JNICALL
 103 Java_java_lang_Class_forName0(JNIEnv *env, jclass this, jstring classname,
 104                               jboolean initialize, jobject loader, jclass caller)
 105 {
 106     char *clname;
 107     jclass cls = 0;
 108     char buf[128];
 109     jsize len;
 110     jsize unicode_len;
 111 
 112     if (classname == NULL) {
 113         JNU_ThrowNullPointerException(env, 0);
 114         return 0;
 115     }
 116 
 117     len = (*env)->GetStringUTFLength(env, classname);
 118     unicode_len = (*env)->GetStringLength(env, classname);
 119     if (len >= (jsize)sizeof(buf)) {
 120         clname = malloc(len + 1);
 121         if (clname == NULL) {
 122             JNU_ThrowOutOfMemoryError(env, NULL);
 123             return NULL;
 124         }
 125     } else {
 126         clname = buf;
 127     }
 128     (*env)->GetStringUTFRegion(env, classname, 0, unicode_len, clname);
 129 
 130     if (verifyFixClassname(clname) == JNI_TRUE) {
 131         /* slashes present in clname, use name b4 translation for exception */
 132         (*env)->GetStringUTFRegion(env, classname, 0, unicode_len, clname);
 133         JNU_ThrowClassNotFoundException(env, clname);
 134         goto done;
 135     }
 136 
 137     if (!verifyClassname(clname, JNI_TRUE)) {  /* expects slashed name */
 138         JNU_ThrowClassNotFoundException(env, clname);
 139         goto done;
 140     }
 141 
 142     cls = JVM_FindClassFromCaller(env, clname, initialize, loader, caller);
 143 
 144  done:
 145     if (clname != buf) {
 146         free(clname);
 147     }
 148     return cls;
 149 }
 150 
 151 JNIEXPORT jboolean JNICALL
 152 Java_java_lang_Class_isInstance(JNIEnv *env, jobject cls, jobject obj)
 153 {
 154     if (obj == NULL) {
 155         return JNI_FALSE;
 156     }
 157     return (*env)->IsInstanceOf(env, obj, (jclass)cls);
 158 }
 159 
 160 JNIEXPORT jboolean JNICALL
 161 Java_java_lang_Class_isAssignableFrom(JNIEnv *env, jobject cls, jobject cls2)
 162 {
 163     if (cls2 == NULL) {
 164         JNU_ThrowNullPointerException(env, 0);
 165         return JNI_FALSE;
 166     }
 167     return (*env)->IsAssignableFrom(env, cls2, cls);
 168 }
 169 
 170 JNIEXPORT jclass JNICALL
 171 Java_java_lang_Class_getPrimitiveClass(JNIEnv *env,
 172                                        jclass cls,
 173                                        jstring name)
 174 {
 175     const char *utfName;
 176     jclass result;
 177 
 178     if (name == NULL) {
 179         JNU_ThrowNullPointerException(env, 0);
 180         return NULL;
 181     }
 182 
 183     utfName = (*env)->GetStringUTFChars(env, name, 0);
 184     if (utfName == 0)
 185         return NULL;
 186 
 187     result = JVM_FindPrimitiveClass(env, utfName);
 188 
 189     (*env)->ReleaseStringUTFChars(env, name, utfName);
 190 
 191     return result;
 192 }