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 "java_lang_Class.h"
  39 
  40 /* defined in libverify.so/verify.dll (src file common/check_format.c) */
  41 extern jboolean VerifyClassname(char *utf_name, jboolean arrayAllowed);
  42 extern jboolean VerifyFixClassname(char *utf_name);
  43 
  44 #define OBJ "Ljava/lang/Object;"
  45 #define CLS "Ljava/lang/Class;"
  46 #define CPL "Ljdk/internal/reflect/ConstantPool;"
  47 #define STR "Ljava/lang/String;"
  48 #define FLD "Ljava/lang/reflect/Field;"
  49 #define MHD "Ljava/lang/reflect/Method;"
  50 #define CTR "Ljava/lang/reflect/Constructor;"
  51 #define PD  "Ljava/security/ProtectionDomain;"
  52 #define BA  "[B"
  53 
  54 static JNINativeMethod methods[] = {
  55     {"initClassName",    "()" STR,              (void *)&JVM_InitClassName},
  56     {"getSuperclass",    "()" CLS,              NULL},
  57     {"getInterfaces0",   "()[" CLS,             (void *)&JVM_GetClassInterfaces},
  58     {"isInterface",      "()Z",                 (void *)&JVM_IsInterface},
  59     {"getSigners",       "()[" OBJ,             (void *)&JVM_GetClassSigners},
  60     {"setSigners",       "([" OBJ ")V",         (void *)&JVM_SetClassSigners},
  61     {"isArray",          "()Z",                 (void *)&JVM_IsArrayClass},
  62     {"isPrimitive",      "()Z",                 (void *)&JVM_IsPrimitiveClass},
  63     {"getModifiers",     "()I",                 (void *)&JVM_GetClassModifiers},
  64     {"getDeclaredFields0","(Z)[" FLD,           (void *)&JVM_GetClassDeclaredFields},
  65     {"getDeclaredMethods0","(Z)[" MHD,          (void *)&JVM_GetClassDeclaredMethods},
  66     {"getDeclaredConstructors0","(Z)[" CTR,     (void *)&JVM_GetClassDeclaredConstructors},
  67     {"getProtectionDomain0", "()" PD,           (void *)&JVM_GetProtectionDomain},
  68     {"getDeclaredClasses0",  "()[" CLS,         (void *)&JVM_GetDeclaredClasses},
  69     {"getDeclaringClass0",   "()" CLS,          (void *)&JVM_GetDeclaringClass},
  70     {"getSimpleBinaryName0", "()" STR,          (void *)&JVM_GetSimpleBinaryName},
  71     {"getGenericSignature0", "()" STR,          (void *)&JVM_GetClassSignature},
  72     {"getRawAnnotations",      "()" BA,         (void *)&JVM_GetClassAnnotations},
  73     {"getConstantPool",     "()" CPL,           (void *)&JVM_GetClassConstantPool},
  74     {"desiredAssertionStatus0","("CLS")Z",      (void *)&JVM_DesiredAssertionStatus},
  75     {"getEnclosingMethod0", "()[" OBJ,          (void *)&JVM_GetEnclosingMethodInfo},
  76     {"getRawTypeAnnotations", "()" BA,          (void *)&JVM_GetClassTypeAnnotations},
  77     {"getNestHost0",         "()" CLS,          (void *)&JVM_GetNestHost},
  78     {"getNestMembers0",      "()[" CLS,         (void *)&JVM_GetNestMembers},
  79     {"getPermittedSubtypes0", "()[" CLS,        (void *)&JVM_GetPermittedSubtypes},
  80     {"getRecordComponentNames0",  "()[" STR,    (void *)&JVM_GetRecordComponentNames},
  81     {"isRecord0",                 "()Z",        (void *)&JVM_IsRecord},
  82 };
  83 
  84 #undef OBJ
  85 #undef CLS
  86 #undef STR
  87 #undef FLD
  88 #undef MHD
  89 #undef CTR
  90 #undef PD
  91 
  92 JNIEXPORT void JNICALL
  93 Java_java_lang_Class_registerNatives(JNIEnv *env, jclass cls)
  94 {
  95     methods[1].fnPtr = (void *)(*env)->GetSuperclass;
  96     (*env)->RegisterNatives(env, cls, methods,
  97                             sizeof(methods)/sizeof(JNINativeMethod));
  98 }
  99 
 100 JNIEXPORT jclass JNICALL
 101 Java_java_lang_Class_forName0(JNIEnv *env, jclass this, jstring classname,
 102                               jboolean initialize, jobject loader, jclass caller)
 103 {
 104     char *clname;
 105     jclass cls = 0;
 106     char buf[128];
 107     jsize len;
 108     jsize unicode_len;
 109 
 110     if (classname == NULL) {
 111         JNU_ThrowNullPointerException(env, 0);
 112         return 0;
 113     }
 114 
 115     len = (*env)->GetStringUTFLength(env, classname);
 116     unicode_len = (*env)->GetStringLength(env, classname);
 117     if (len >= (jsize)sizeof(buf)) {
 118         clname = malloc(len + 1);
 119         if (clname == NULL) {
 120             JNU_ThrowOutOfMemoryError(env, NULL);
 121             return NULL;
 122         }
 123     } else {
 124         clname = buf;
 125     }
 126     (*env)->GetStringUTFRegion(env, classname, 0, unicode_len, clname);
 127 
 128     if (VerifyFixClassname(clname) == JNI_TRUE) {
 129         /* slashes present in clname, use name b4 translation for exception */
 130         (*env)->GetStringUTFRegion(env, classname, 0, unicode_len, clname);
 131         JNU_ThrowClassNotFoundException(env, clname);
 132         goto done;
 133     }
 134 
 135     if (!VerifyClassname(clname, JNI_TRUE)) {  /* expects slashed name */
 136         JNU_ThrowClassNotFoundException(env, clname);
 137         goto done;
 138     }
 139 
 140     cls = JVM_FindClassFromCaller(env, clname, initialize, loader, caller);
 141 
 142  done:
 143     if (clname != buf) {
 144         free(clname);
 145     }
 146     return cls;
 147 }
 148 
 149 JNIEXPORT jboolean JNICALL
 150 Java_java_lang_Class_isInstance(JNIEnv *env, jobject cls, jobject obj)
 151 {
 152     if (obj == NULL) {
 153         return JNI_FALSE;
 154     }
 155     return (*env)->IsInstanceOf(env, obj, (jclass)cls);
 156 }
 157 
 158 JNIEXPORT jboolean JNICALL
 159 Java_java_lang_Class_isAssignableFrom(JNIEnv *env, jobject cls, jobject cls2)
 160 {
 161     if (cls2 == NULL) {
 162         JNU_ThrowNullPointerException(env, 0);
 163         return JNI_FALSE;
 164     }
 165     return (*env)->IsAssignableFrom(env, cls2, cls);
 166 }
 167 
 168 JNIEXPORT jclass JNICALL
 169 Java_java_lang_Class_getPrimitiveClass(JNIEnv *env,
 170                                        jclass cls,
 171                                        jstring name)
 172 {
 173     const char *utfName;
 174     jclass result;
 175 
 176     if (name == NULL) {
 177         JNU_ThrowNullPointerException(env, 0);
 178         return NULL;
 179     }
 180 
 181     utfName = (*env)->GetStringUTFChars(env, name, 0);
 182     if (utfName == 0)
 183         return NULL;
 184 
 185     result = JVM_FindPrimitiveClass(env, utfName);
 186 
 187     (*env)->ReleaseStringUTFChars(env, name, utfName);
 188 
 189     return result;
 190 }