/*

 * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include "precompiled.hpp"

#include "memory/allocation.hpp"

#include "memory/allocation.inline.hpp"

#include "memory/guardedMemory.hpp"

#include "runtime/os.hpp"

#include "unittest.hpp"

#define GEN_PURPOSE_TAG ((void *) ((uintptr_t)0xf000f000))

static void guarded_memory_test_check(void* p, size_t sz, void* tag) {

  ASSERT_TRUE(p != NULL) << "NULL pointer given to check";

  u_char* c = (u_char*) p;

  GuardedMemory guarded(c);

  EXPECT_EQ(guarded.get_tag(), tag) << "Tag is not the same as supplied";

  EXPECT_EQ(guarded.get_user_ptr(), c) << "User pointer is not the same as supplied";

  EXPECT_EQ(guarded.get_user_size(), sz) << "User size is not the same as supplied";

  EXPECT_TRUE(guarded.verify_guards()) << "Guard broken";

}

class GuardedMemoryTest {

 public:

  static size_t get_guard_header_size() {

    return sizeof (GuardedMemory::GuardHeader);

  }

  static size_t get_guard_size() {

    return sizeof (GuardedMemory::Guard);

  }

};

// Test GuardedMemory size

TEST(GuardedMemory, size) {

  size_t total_sz = GuardedMemory::get_total_size(1);

  ASSERT_GT(total_sz, (size_t) 1) << "Unexpected size";

  ASSERT_GE(total_sz, GuardedMemoryTest::get_guard_header_size() + 1

          + GuardedMemoryTest::get_guard_size()) << "Unexpected size";

}

// Test the basic characteristics

TEST(GuardedMemory, basic) {

  u_char* basep =

          (u_char*) os::malloc(GuardedMemory::get_total_size(1), mtInternal);

  GuardedMemory guarded(basep, 1, GEN_PURPOSE_TAG);

  EXPECT_EQ(badResourceValue, *basep)

          << "Expected guard in the form of badResourceValue";

  u_char* userp = guarded.get_user_ptr();

  EXPECT_EQ(uninitBlockPad, *userp)

          << "Expected uninitialized data in the form of uninitBlockPad";

  guarded_memory_test_check(userp, 1, GEN_PURPOSE_TAG);

  void* freep = guarded.release_for_freeing();

  EXPECT_EQ((u_char*) freep, basep) << "Expected the same pointer guard was ";

  EXPECT_EQ(freeBlockPad, *userp) << "Expected user data to be free block padded";

  EXPECT_FALSE(guarded.verify_guards());

  os::free(freep);

}

// Test a number of odd sizes

TEST(GuardedMemory, odd_sizes) {

  u_char* basep =

          (u_char*) os::malloc(GuardedMemory::get_total_size(1), mtInternal);

  GuardedMemory guarded(basep, 1, GEN_PURPOSE_TAG);

  size_t sz = 0;

  do {

    void* p = os::malloc(GuardedMemory::get_total_size(sz), mtInternal);

    void* up = guarded.wrap_with_guards(p, sz, (void*) 1);

    memset(up, 0, sz);

    guarded_memory_test_check(up, sz, (void*) 1);

    if (HasFatalFailure()) {

      return;

    }

    os::free(guarded.release_for_freeing());

    sz = (sz << 4) + 1;

  } while (sz < (256 * 1024));

}

// Test buffer overrun into head...

TEST(GuardedMemory, buffer_overrun_head) {

  u_char* basep =

          (u_char*) os::malloc(GuardedMemory::get_total_size(1), mtInternal);

  GuardedMemory guarded(basep, 1, GEN_PURPOSE_TAG);

  guarded.wrap_with_guards(basep, 1);

  *basep = 0;

  EXPECT_FALSE(guarded.verify_guards());

  os::free(basep);

}

// Test buffer overrun into tail with a number of odd sizes

TEST(GuardedMemory, buffer_overrun_tail) {

  u_char* basep =

          (u_char*) os::malloc(GuardedMemory::get_total_size(1), mtInternal);

  GuardedMemory guarded(basep, 1, GEN_PURPOSE_TAG);

  size_t sz = 1;

  do {

    void* p = os::malloc(GuardedMemory::get_total_size(sz), mtInternal);

    void* up = guarded.wrap_with_guards(p, sz, (void*) 1);

    memset(up, 0, sz + 1); // Buffer-overwrite (within guard)

    EXPECT_FALSE(guarded.verify_guards()) << "Guard was not broken as expected";

    os::free(guarded.release_for_freeing());

    sz = (sz << 4) + 1;

  } while (sz < (256 * 1024));

}

// Test wrap_copy/wrap_free

TEST(GuardedMemory, wrap) {

  EXPECT_TRUE(GuardedMemory::free_copy(NULL)) << "Expected free NULL to be OK";

  const char* str = "Check my bounds out";

  size_t str_sz = strlen(str) + 1;

  char* str_copy = (char*) GuardedMemory::wrap_copy(str, str_sz);

  guarded_memory_test_check(str_copy, str_sz, NULL);

  if (HasFatalFailure()) {

    return;

  }

  EXPECT_EQ(0, strcmp(str, str_copy)) << "Not identical copy";

  EXPECT_TRUE(GuardedMemory::free_copy(str_copy)) << "Free copy failed to verify";

  void* no_data = NULL;

  void* no_data_copy = GuardedMemory::wrap_copy(no_data, 0);

  EXPECT_TRUE(GuardedMemory::free_copy(no_data_copy))

          << "Expected valid guards even for no data copy";

}