1 /*
  2  * Copyright (c) 1994, 2022, 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     {"isIdentity",       "()Z",             (void *)&JVM_IsIdentityClass},
 66     {"isPrimitive",      "()Z",             (void *)&JVM_IsPrimitiveClass},
 67     {"getModifiers",     "()I",             (void *)&JVM_GetClassModifiers},
 68     {"getDeclaredFields0","(Z)[" FLD,       (void *)&JVM_GetClassDeclaredFields},
 69     {"getDeclaredMethods0","(Z)[" MHD,      (void *)&JVM_GetClassDeclaredMethods},
 70     {"getDeclaredConstructors0","(Z)[" CTR, (void *)&JVM_GetClassDeclaredConstructors},
 71     {"getProtectionDomain0", "()" PD,       (void *)&JVM_GetProtectionDomain},
 72     {"getDeclaredClasses0",  "()[" CLS,     (void *)&JVM_GetDeclaredClasses},
 73     {"getDeclaringClass0",   "()" CLS,      (void *)&JVM_GetDeclaringClass},
 74     {"getSimpleBinaryName0", "()" STR,      (void *)&JVM_GetSimpleBinaryName},
 75     {"getGenericSignature0", "()" STR,      (void *)&JVM_GetClassSignature},
 76     {"getRawAnnotations",      "()" BA,     (void *)&JVM_GetClassAnnotations},
 77     {"getConstantPool",     "()" CPL,       (void *)&JVM_GetClassConstantPool},
 78     {"desiredAssertionStatus0","("CLS")Z",  (void *)&JVM_DesiredAssertionStatus},
 79     {"getEnclosingMethod0", "()[" OBJ,      (void *)&JVM_GetEnclosingMethodInfo},
 80     {"getRawTypeAnnotations", "()" BA,      (void *)&JVM_GetClassTypeAnnotations},
 81     {"getNestHost0",         "()" CLS,      (void *)&JVM_GetNestHost},
 82     {"getNestMembers0",      "()[" CLS,     (void *)&JVM_GetNestMembers},
 83     {"getRecordComponents0", "()[" RC,      (void *)&JVM_GetRecordComponents},
 84     {"isRecord0",            "()Z",         (void *)&JVM_IsRecord},
 85     {"getPermittedSubclasses0", "()[" CLS,  (void *)&JVM_GetPermittedSubclasses},
 86     {"getClassFileVersion0", "()I",         (void *)&JVM_GetClassFileVersion},
 87     {"getClassAccessFlagsRaw0", "()I",      (void *)&JVM_GetClassAccessFlags},
 88 };
 89 
 90 #undef OBJ
 91 #undef CLS
 92 #undef STR
 93 #undef FLD
 94 #undef MHD
 95 #undef CTR
 96 #undef PD
 97 
 98 JNIEXPORT void JNICALL
 99 Java_java_lang_Class_registerNatives(JNIEnv *env, jclass cls)
100 {
101     methods[1].fnPtr = (void *)(*env)->GetSuperclass;
102     (*env)->RegisterNatives(env, cls, methods,
103                             sizeof(methods)/sizeof(JNINativeMethod));
104 }
105 
106 JNIEXPORT jclass JNICALL
107 Java_java_lang_Class_forName0(JNIEnv *env, jclass this, jstring classname,
108                               jboolean initialize, jobject loader, jclass caller)
109 {
110     char *clname;
111     jclass cls = 0;
112     char buf[128];
113     jsize len;
114     jsize unicode_len;
115 
116     if (classname == NULL) {
117         JNU_ThrowNullPointerException(env, 0);
118         return 0;
119     }
120 
121     len = (*env)->GetStringUTFLength(env, classname);
122     unicode_len = (*env)->GetStringLength(env, classname);
123     if (len >= (jsize)sizeof(buf)) {
124         clname = malloc(len + 1);
125         if (clname == NULL) {
126             JNU_ThrowOutOfMemoryError(env, NULL);
127             return NULL;
128         }
129     } else {
130         clname = buf;
131     }
132     (*env)->GetStringUTFRegion(env, classname, 0, unicode_len, clname);
133 
134     if (verifyFixClassname(clname) == JNI_TRUE) {
135         /* slashes present in clname, use name b4 translation for exception */
136         (*env)->GetStringUTFRegion(env, classname, 0, unicode_len, clname);
137         JNU_ThrowClassNotFoundException(env, clname);
138         goto done;
139     }
140 
141     if (!verifyClassname(clname, JNI_TRUE)) {  /* expects slashed name */
142         JNU_ThrowClassNotFoundException(env, clname);
143         goto done;
144     }
145 
146     cls = JVM_FindClassFromCaller(env, clname, initialize, loader, caller);
147 
148  done:
149     if (clname != buf) {
150         free(clname);
151     }
152     return cls;
153 }
154 
155 JNIEXPORT jboolean JNICALL
156 Java_java_lang_Class_isInstance(JNIEnv *env, jobject cls, jobject obj)
157 {
158     if (obj == NULL) {
159         return JNI_FALSE;
160     }
161     return (*env)->IsInstanceOf(env, obj, (jclass)cls);
162 }
163 
164 JNIEXPORT jboolean JNICALL
165 Java_java_lang_Class_isAssignableFrom(JNIEnv *env, jobject cls, jobject cls2)
166 {
167     if (cls2 == NULL) {
168         JNU_ThrowNullPointerException(env, 0);
169         return JNI_FALSE;
170     }
171     return (*env)->IsAssignableFrom(env, cls2, cls);
172 }
173 
174 JNIEXPORT jclass JNICALL
175 Java_java_lang_Class_getPrimitiveClass(JNIEnv *env,
176                                        jclass cls,
177                                        jstring name)
178 {
179     const char *utfName;
180     jclass result;
181 
182     if (name == NULL) {
183         JNU_ThrowNullPointerException(env, 0);
184         return NULL;
185     }
186 
187     utfName = (*env)->GetStringUTFChars(env, name, 0);
188     if (utfName == 0)
189         return NULL;
190 
191     result = JVM_FindPrimitiveClass(env, utfName);
192 
193     (*env)->ReleaseStringUTFChars(env, name, utfName);
194 
195     return result;
196 }