/*
* For some of the reflection stuff we need to un-box primitives, e.g.
* convert a java/lang/Integer to int or even a float. We assume that
* the first instance field holds the value.
*
* To verify this, we either need to ensure that the class has only one
* instance field, or we need to look up the field by name and verify
* that it comes first. The former is simpler, and should work.
*/
bool dvmValidateBoxClasses()
{
static const char* classes[] = {
"Ljava/lang/Boolean;",
"Ljava/lang/Character;",
"Ljava/lang/Float;",
"Ljava/lang/Double;",
"Ljava/lang/Byte;",
"Ljava/lang/Short;",
"Ljava/lang/Integer;",
"Ljava/lang/Long;",
NULL
};
const char** ccp;
for (ccp = classes; *ccp != NULL; ccp++) {
ClassObject* clazz;
clazz = dvmFindClassNoInit(*ccp, NULL);
if (clazz == NULL) {
ALOGE("Couldn't find '%s'", *ccp);
return false;
}
if (clazz->ifieldCount != 1) {
ALOGE("Found %d instance fields in '%s'",
clazz->ifieldCount, *ccp);
return false;
}
}
return true;
}
/*
* Find a class by name, initializing it if requested.
*/
ClassObject* dvmFindClassByName(StringObject* nameObj, Object* loader,
bool doInit)
{
ClassObject* clazz = NULL;
char* name = NULL;
char* descriptor = NULL;
if (nameObj == NULL) {
dvmThrowException("Ljava/lang/NullPointerException;", NULL);
goto bail;
}
name = dvmCreateCstrFromString(nameObj);
/*
* We need to validate and convert the name (from x.y.z to x/y/z). This
* is especially handy for array types, since we want to avoid
* auto-generating bogus array classes.
*/
if (!validateClassName(name)) {
LOGW("dvmFindClassByName rejecting '%s'\n", name);
dvmThrowException("Ljava/lang/ClassNotFoundException;", name);
goto bail;
}
descriptor = dvmDotToDescriptor(name);
if (descriptor == NULL) {
goto bail;
}
if (doInit)
clazz = dvmFindClass(descriptor, loader);
else
clazz = dvmFindClassNoInit(descriptor, loader);
if (clazz == NULL) {
LOGVV("FAIL: load %s (%d)\n", descriptor, doInit);
Thread* self = dvmThreadSelf();
Object* oldExcep = dvmGetException(self);
dvmAddTrackedAlloc(oldExcep, self); /* don't let this be GCed */
dvmClearException(self);
dvmThrowChainedException("Ljava/lang/ClassNotFoundException;",
name, oldExcep);
dvmReleaseTrackedAlloc(oldExcep, self);
} else {
LOGVV("GOOD: load %s (%d) --> %p ldr=%p\n",
descriptor, doInit, clazz, clazz->classLoader);
}
bail:
free(name);
free(descriptor);
return clazz;
}
/*
* Determine if "method" is a "privileged" invocation, i.e. is it one
* of the variations of AccessController.doPrivileged().
*
* Because the security stuff pulls in a pile of stuff that we may not
* want or need, we don't do the class/method lookups at init time, but
* instead on first use.
*/
bool dvmIsPrivilegedMethod(const Method* method)
{
int i;
assert(method != NULL);
if (!gDvm.javaSecurityAccessControllerReady) {
/*
* Populate on first use. No concurrency risk since we're just
* finding pointers to fixed structures.
*/
static const char* kSignatures[NUM_DOPRIV_FUNCS] = {
"(Ljava/security/PrivilegedAction;)Ljava/lang/Object;",
"(Ljava/security/PrivilegedExceptionAction;)Ljava/lang/Object;",
"(Ljava/security/PrivilegedAction;Ljava/security/AccessControlContext;)Ljava/lang/Object;",
"(Ljava/security/PrivilegedExceptionAction;Ljava/security/AccessControlContext;)Ljava/lang/Object;",
};
ClassObject* clazz;
clazz = dvmFindClassNoInit("Ljava/security/AccessController;", NULL);
if (clazz == NULL) {
LOGW("Couldn't find java/security/AccessController\n");
return false;
}
assert(NELEM(gDvm.methJavaSecurityAccessController_doPrivileged) ==
NELEM(kSignatures));
/* verify init */
for (i = 0; i < NUM_DOPRIV_FUNCS; i++) {
gDvm.methJavaSecurityAccessController_doPrivileged[i] =
dvmFindDirectMethodByDescriptor(clazz, "doPrivileged", kSignatures[i]);
if (gDvm.methJavaSecurityAccessController_doPrivileged[i] == NULL) {
LOGW("Warning: couldn't find java/security/AccessController"
".doPrivileged %s\n", kSignatures[i]);
return false;
}
}
/* all good, raise volatile readiness flag */
android_atomic_release_store(true,
&gDvm.javaSecurityAccessControllerReady);
}
for (i = 0; i < NUM_DOPRIV_FUNCS; i++) {
if (gDvm.methJavaSecurityAccessController_doPrivileged[i] == method) {
//LOGI("+++ doPriv match\n");
return true;
}
}
return false;
}
/*
* Make an inline call for the "debug" interpreter, used when the debugger
* or profiler is active.
*/
bool dvmPerformInlineOp4Dbg(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult, int opIndex)
{
Thread* self = dvmThreadSelf();
bool result;
assert(opIndex >= 0 && opIndex < NELEM(gDvmInlineOpsTable));
#ifdef WITH_PROFILER
/*
* Populate the methods table on first use. It's possible the class
* hasn't been resolved yet, so we need to do the full "calling the
* method for the first time" routine. (It's probably okay to skip
* the access checks.)
*
* Currently assuming that we're only inlining stuff loaded by the
* bootstrap class loader. This is a safe assumption for many reasons.
*/
Method* method = gDvm.inlinedMethods[opIndex];
if (method == NULL) {
ClassObject* clazz;
clazz = dvmFindClassNoInit(
gDvmInlineOpsTable[opIndex].classDescriptor, NULL);
if (clazz == NULL) {
LOGW("Warning: can't find class '%s'\n", clazz->descriptor);
goto skip_prof;
}
method = dvmFindDirectMethodByDescriptor(clazz,
gDvmInlineOpsTable[opIndex].methodName,
gDvmInlineOpsTable[opIndex].methodSignature);
if (method == NULL)
method = dvmFindVirtualMethodByDescriptor(clazz,
gDvmInlineOpsTable[opIndex].methodName,
gDvmInlineOpsTable[opIndex].methodSignature);
if (method == NULL) {
LOGW("Warning: can't find method %s.%s %s\n",
clazz->descriptor,
gDvmInlineOpsTable[opIndex].methodName,
gDvmInlineOpsTable[opIndex].methodSignature);
goto skip_prof;
}
gDvm.inlinedMethods[opIndex] = method;
IF_LOGV() {
char* desc = dexProtoCopyMethodDescriptor(&method->prototype);
LOGV("Registered for profile: %s.%s %s\n",
method->clazz->descriptor, method->name, desc);
free(desc);
}
}
Method* dvmFindInlinableMethod(const char* classDescriptor,
const char* methodName, const char* methodSignature)
{
/*
* Find the class.
*/
ClassObject* clazz = dvmFindClassNoInit(classDescriptor, NULL);
if (clazz == NULL) {
ALOGE("dvmFindInlinableMethod: can't find class '%s'",
classDescriptor);
dvmClearException(dvmThreadSelf());
return NULL;
}
/*
* Method could be virtual or direct. Try both. Don't use
* the "hier" versions.
*/
Method* method = dvmFindDirectMethodByDescriptor(clazz, methodName,
methodSignature);
if (method == NULL) {
method = dvmFindVirtualMethodByDescriptor(clazz, methodName,
methodSignature);
}
if (method == NULL) {
ALOGE("dvmFindInlinableMethod: can't find method %s.%s %s",
clazz->descriptor, methodName, methodSignature);
return NULL;
}
/*
* Check that the method is appropriate for inlining.
*/
if (!dvmIsFinalClass(clazz) && !dvmIsFinalMethod(method)) {
ALOGE("dvmFindInlinableMethod: can't inline non-final method %s.%s",
clazz->descriptor, method->name);
return NULL;
}
if (dvmIsSynchronizedMethod(method) ||
dvmIsDeclaredSynchronizedMethod(method)) {
ALOGE("dvmFindInlinableMethod: can't inline synchronized method %s.%s",
clazz->descriptor, method->name);
return NULL;
}
return method;
}
/*
* Find the named class object. We have to trim "*pSignature" down to just
* the first token, do the lookup, and then restore anything important
* that we've stomped on.
*
* "pSig" will be advanced to the start of the next token.
*/
static ClassObject* convertSignaturePartToClass(char** pSignature,
const ClassObject* defClass)
{
ClassObject* clazz = NULL;
char* signature = *pSignature;
if (*signature == '[') {
/* looks like "[[[Landroid/debug/Stuff;"; we want the whole thing */
char savedChar;
while (*++signature == '[')
;
if (*signature == 'L') {
while (*++signature != ';')
;
}
/* advance past ';', and stomp on whatever comes next */
savedChar = *++signature;
*signature = '\0';
clazz = dvmFindArrayClass(*pSignature, defClass->classLoader);
*signature = savedChar;
} else if (*signature == 'L') {
/* looks like 'Landroid/debug/Stuff;"; we want the whole thing */
char savedChar;
while (*++signature != ';')
;
savedChar = *++signature;
*signature = '\0';
clazz = dvmFindClassNoInit(*pSignature, defClass->classLoader);
*signature = savedChar;
} else {
clazz = dvmFindPrimitiveClass(*signature++);
}
if (clazz == NULL) {
ALOGW("Unable to match class for part: '%s'", *pSignature);
}
*pSignature = signature;
return clazz;
}
/*
* Find the class corresponding to "classIdx", which maps to a class name
* string. It might be in the same DEX file as "referrer", in a different
* DEX file, generated by a class loader, or generated by the VM (e.g.
* array classes).
*
* Because the DexTypeId is associated with the referring class' DEX file,
* we may have to resolve the same class more than once if it's referred
* to from classes in multiple DEX files. This is a necessary property for
* DEX files associated with different class loaders.
*
* We cache a copy of the lookup in the DexFile's "resolved class" table,
* so future references to "classIdx" are faster.
*
* Note that "referrer" may be in the process of being linked.
*
* Traditional VMs might do access checks here, but in Dalvik the class
* "constant pool" is shared between all classes in the DEX file. We rely
* on the verifier to do the checks for us.
*
* Does not initialize the class.
*
* "fromUnverifiedConstant" should only be set if this call is the direct
* result of executing a "const-class" or "instance-of" instruction, which
* use class constants not resolved by the bytecode verifier.
*
* Returns NULL with an exception raised on failure.
*/
ClassObject* dvmResolveClass(const ClassObject* referrer, u4 classIdx,
bool fromUnverifiedConstant)
{
DvmDex* pDvmDex = referrer->pDvmDex;
ClassObject* resClass;
const char* className;
/*
* Check the table first -- this gets called from the other "resolve"
* methods.
*/
resClass = dvmDexGetResolvedClass(pDvmDex, classIdx);
if (resClass != NULL)
return resClass;
LOGVV("--- resolving class %u (referrer=%s cl=%p)\n",
classIdx, referrer->descriptor, referrer->classLoader);
/*
* Class hasn't been loaded yet, or is in the process of being loaded
* and initialized now. Try to get a copy. If we find one, put the
* pointer in the DexTypeId. There isn't a race condition here --
* 32-bit writes are guaranteed atomic on all target platforms. Worst
* case we have two threads storing the same value.
*
* If this is an array class, we'll generate it here.
*/
className = dexStringByTypeIdx(pDvmDex->pDexFile, classIdx);
if (className[0] != '\0' && className[1] == '\0') {
/* primitive type */
resClass = dvmFindPrimitiveClass(className[0]);
} else {
resClass = dvmFindClassNoInit(className, referrer->classLoader);
}
if (resClass != NULL) {
/*
* If the referrer was pre-verified, the resolved class must come
* from the same DEX or from a bootstrap class. The pre-verifier
* makes assumptions that could be invalidated by a wacky class
* loader. (See the notes at the top of oo/Class.c.)
*
* The verifier does *not* fail a class for using a const-class
* or instance-of instruction referring to an unresolveable class,
* because the result of the instruction is simply a Class object
* or boolean -- there's no need to resolve the class object during
* verification. Instance field and virtual method accesses can
* break dangerously if we get the wrong class, but const-class and
* instance-of are only interesting at execution time. So, if we
* we got here as part of executing one of the "unverified class"
* instructions, we skip the additional check.
*
* Ditto for class references from annotations and exception
* handler lists.
*/
if (!fromUnverifiedConstant &&
IS_CLASS_FLAG_SET(referrer, CLASS_ISPREVERIFIED))
{
ClassObject* resClassCheck = resClass;
if (dvmIsArrayClass(resClassCheck))
resClassCheck = resClassCheck->elementClass;
if (referrer->pDvmDex != resClassCheck->pDvmDex &&
resClassCheck->classLoader != NULL)
{
LOGW("Class resolved by unexpected DEX:"
" %s(%p):%p ref [%s] %s(%p):%p\n",
referrer->descriptor, referrer->classLoader,
referrer->pDvmDex,
resClass->descriptor, resClassCheck->descriptor,
resClassCheck->classLoader, resClassCheck->pDvmDex);
LOGW("(%s had used a different %s during pre-verification)\n",
referrer->descriptor, resClass->descriptor);
dvmThrowException("Ljava/lang/IllegalAccessError;",
"Class ref in pre-verified class resolved to unexpected "
"implementation");
return NULL;
}
}
LOGVV("##### +ResolveClass(%s): referrer=%s dex=%p ldr=%p ref=%d\n",
resClass->descriptor, referrer->descriptor, referrer->pDvmDex,
referrer->classLoader, classIdx);
/*
* Add what we found to the list so we can skip the class search
* next time through.
*
* TODO: should we be doing this when fromUnverifiedConstant==true?
* (see comments at top of oo/Class.c)
*/
dvmDexSetResolvedClass(pDvmDex, classIdx, resClass);
} else {
/* not found, exception should be raised */
LOGVV("Class not found: %s\n",
dexStringByTypeIdx(pDvmDex->pDexFile, classIdx));
assert(dvmCheckException(dvmThreadSelf()));
}
return resClass;
}
/*
* Alternate version of dvmResolveClass for use with verification and
* optimization. Performs access checks on every resolve, and refuses
* to acknowledge the existence of classes defined in more than one DEX
* file.
*
* Exceptions caused by failures are cleared before returning.
*
* On failure, returns NULL, and sets *pFailure if pFailure is not NULL.
*/
ClassObject* dvmOptResolveClass(ClassObject* referrer, u4 classIdx,
VerifyError* pFailure)
{
DvmDex* pDvmDex = referrer->pDvmDex;
ClassObject* resClass;
/*
* Check the table first. If not there, do the lookup by name.
*/
resClass = dvmDexGetResolvedClass(pDvmDex, classIdx);
if (resClass == NULL) {
const char* className = dexStringByTypeIdx(pDvmDex->pDexFile, classIdx);
if (className[0] != '\0' && className[1] == '\0') {
/* primitive type */
resClass = dvmFindPrimitiveClass(className[0]);
} else {
resClass = dvmFindClassNoInit(className, referrer->classLoader);
}
if (resClass == NULL) {
/* not found, exception should be raised */
ALOGV("DexOpt: class %d (%s) not found",
classIdx,
dexStringByTypeIdx(pDvmDex->pDexFile, classIdx));
if (pFailure != NULL) {
/* dig through the wrappers to find the original failure */
Object* excep = dvmGetException(dvmThreadSelf());
while (true) {
Object* cause = dvmGetExceptionCause(excep);
if (cause == NULL)
break;
excep = cause;
}
if (strcmp(excep->clazz->descriptor,
"Ljava/lang/IncompatibleClassChangeError;") == 0)
{
*pFailure = VERIFY_ERROR_CLASS_CHANGE;
} else {
*pFailure = VERIFY_ERROR_NO_CLASS;
}
}
dvmClearOptException(dvmThreadSelf());
return NULL;
}
/*
* Add it to the resolved table so we're faster on the next lookup.
*/
dvmDexSetResolvedClass(pDvmDex, classIdx, resClass);
}
/* multiple definitions? */
if (IS_CLASS_FLAG_SET(resClass, CLASS_MULTIPLE_DEFS)) {
ALOGI("DexOpt: not resolving ambiguous class '%s'",
resClass->descriptor);
if (pFailure != NULL)
*pFailure = VERIFY_ERROR_NO_CLASS;
return NULL;
}
/* access allowed? */
tweakLoader(referrer, resClass);
bool allowed = dvmCheckClassAccess(referrer, resClass);
untweakLoader(referrer, resClass);
if (!allowed) {
ALOGW("DexOpt: resolve class illegal access: %s -> %s",
referrer->descriptor, resClass->descriptor);
if (pFailure != NULL)
*pFailure = VERIFY_ERROR_ACCESS_CLASS;
return NULL;
}
return resClass;
}
