commit 4a801a4f0138a3a4a5a7615af567c5755abe0d7a
author jeffhao <jeffhao@google.com> Fri Sep 23 13:53:40 2011 -0700
committer jeffhao <jeffhao@google.com> Fri Sep 23 14:36:31 2011 -0700
tree b8844bef8e4cf5502e52233d32ed4bf0230b36e4
parent d1bb4f6b7c8dda429f61937cd42f3a0b7367c271

Enabled access check for classes and methods in the verifier.

All checks should pass in frameworks. The only thing left in the
verifier is to tolerate classes/methods/fields that fail to resolve
initially.

Change-Id: I2afe0295bb16542259b2122a9056b3139d908871

src/dex_verifier.cc

diff --git a/src/dex_verifier.cc b/src/dex_verifier.cc
index ebb71b2..6ea276f 100644
--- a/src/dex_verifier.cc
+++ b/src/dex_verifier.cc
@@ -4366,7 +4366,6 @@
     return NULL;
   }
 
-#if 0
   /* Check if access is allowed. */
   if (!referrer->CanAccess(res_class)) {
     LOG(ERROR) << "VFY: illegal class access: "
@@ -4375,7 +4374,6 @@
     *failure = VERIFY_ERROR_ACCESS_CLASS;
     return NULL;
   }
-#endif
 
   return res_class;
 }
@@ -4414,9 +4412,8 @@
     }
   }
 
-#if 0
   /* Check if access is allowed. */
-  if (!referrer->CanAccess(res_method->GetDeclaringClass())) {
+  if (!referrer->CanAccessMember(res_method->GetDeclaringClass(), res_method->GetAccessFlags())) {
     LOG(ERROR) << "VFY: illegal method access (call "
                << res_method->GetDeclaringClass()->GetDescriptor()->ToModifiedUtf8()
                << "." << res_method->GetName()->ToModifiedUtf8() << " "
@@ -4425,7 +4422,6 @@
     *failure = VERIFY_ERROR_ACCESS_METHOD;
     return NULL;
   }
-#endif
 
   return res_method;
 }
@@ -4467,7 +4463,7 @@
   }
 
   /* Check if access is allowed. */
-  if (!referrer->CanAccess(res_field->GetDeclaringClass())) {
+  if (!referrer->CanAccessMember(res_field->GetDeclaringClass(), res_field->GetAccessFlags())) {
     LOG(ERROR) << "VFY: access denied from "
                << referrer->GetDescriptor()->ToModifiedUtf8() << " to field "
                << res_field->GetDeclaringClass()->GetDescriptor()->ToModifiedUtf8()

src/object.cc

diff --git a/src/object.cc b/src/object.cc
index 813abce..64607e8 100644
--- a/src/object.cc
+++ b/src/object.cc
@@ -1030,10 +1030,10 @@
     return false;
   }
   // Arrays are in the same package when their element classes are.
-  if (klass1->IsArrayClass()) {
+  while (klass1->IsArrayClass()) {
     klass1 = klass1->GetComponentType();
   }
-  if (klass2->IsArrayClass()) {
+  while (klass2->IsArrayClass()) {
     klass2 = klass2->GetComponentType();
   }
   // Compare the package part of the descriptor string.

src/object.h

diff --git a/src/object.h b/src/object.h
index 2ee90fc..63a2b30 100644
--- a/src/object.h
+++ b/src/object.h
@@ -1501,6 +1501,35 @@
     return that->IsPublic() || this->IsInSamePackage(that);
   }
 
+  // Validate method/field access.
+  bool CanAccessMember(const Class* access_to, uint32_t member_flags) const {
+    // quick accept for public access
+    if (member_flags & kAccPublic) {
+      return true;
+    }
+
+    // quick accept for access from same class
+    if (this == access_to) {
+      return true;
+    }
+
+    // quick reject for private access from another class
+    if (member_flags & kAccPrivate) {
+      return false;
+    }
+
+    // Semi-quick test for protected access from a sub-class, which may or
+    // may not be in the same package.
+    if (member_flags & kAccProtected) {
+      if (this->IsSubClass(access_to)) {
+        return true;
+      }
+    }
+
+    // Allow protected and private access from other classes in the same package.
+    return this->IsInSamePackage(access_to);
+  }
+
   bool IsSubClass(const Class* klass) const;
 
   bool IsAssignableFrom(const Class* src) const {