// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40284755): Remove this and spanify to fix the errors.
#pragma allow_unsafe_buffers
#endif
#include "base/win/access_control_list.h"
// clang-format off
#include <windows.h> // Must be in front of other Windows header files.
// clang-format on
#include <sddl.h>
#include <string>
#include <vector>
#include "base/check.h"
#include "base/strings/string_number_conversions_win.h"
#include "base/win/scoped_localalloc.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace base::win {
namespace {
constexpr wchar_t kFromPACLTest[] = L"(D;;FX;;;SY)(A;;GA;;;WD)";
constexpr wchar_t kNullAcl[] = L"NO_ACCESS_CONTROL";
constexpr wchar_t kEvent[] = L"(A;;0x1f0003;;;WD)";
constexpr wchar_t kEventWithSystemInherit[] =
L"(D;OICI;DC;;;SY)(A;;0x1f0003;;;WD)";
constexpr wchar_t kEventSystemOnlyInherit[] = L"(D;OICI;DC;;;SY)";
constexpr wchar_t kEventReadControl[] = L"(A;;RC;;;WD)";
constexpr wchar_t kEventReadControlModify[] = L"(A;;DCRC;;;WD)";
constexpr wchar_t kUntrustedLabel[] = L"(ML;;;;;S-1-16-0)";
constexpr wchar_t kSystemLabel[] = L"(ML;;;;;SI)";
constexpr wchar_t kSystemLabelInherit[] = L"(ML;OICI;;;;SI)";
constexpr wchar_t kSystemLabelPolicy[] = L"(ML;;NWNRNX;;;SI)";
constexpr wchar_t kSystemLabelInheritPolicy[] = L"(ML;OICI;NWNRNX;;;SI)";
constexpr wchar_t kDaclPrefix[] = L"D:";
constexpr wchar_t kSaclPrefix[] = L"S:";
std::vector<char> ConvertSddlToAcl(const wchar_t* sddl) {
std::wstring sddl_dacl = kDaclPrefix;
sddl_dacl += sddl;
PSECURITY_DESCRIPTOR sd = nullptr;
CHECK(::ConvertStringSecurityDescriptorToSecurityDescriptor(
sddl_dacl.c_str(), SDDL_REVISION_1, &sd, nullptr));
auto sd_ptr = TakeLocalAlloc(sd);
CHECK(sd_ptr);
BOOL present = FALSE;
BOOL defaulted = FALSE;
PACL dacl = nullptr;
CHECK(::GetSecurityDescriptorDacl(sd_ptr.get(), &present, &dacl, &defaulted));
CHECK(present);
char* dacl_ptr = reinterpret_cast<char*>(dacl);
return std::vector<char>(dacl_ptr, dacl_ptr + dacl->AclSize);
}
std::wstring ConvertAclToSddl(const AccessControlList& acl,
bool label = false) {
SECURITY_DESCRIPTOR sd = {};
CHECK(::InitializeSecurityDescriptor(&sd, SECURITY_DESCRIPTOR_REVISION));
if (label) {
CHECK(::SetSecurityDescriptorSacl(&sd, TRUE, acl.get(), FALSE));
} else {
CHECK(::SetSecurityDescriptorDacl(&sd, TRUE, acl.get(), FALSE));
}
LPWSTR sddl_str = nullptr;
CHECK(::ConvertSecurityDescriptorToStringSecurityDescriptor(
&sd, SDDL_REVISION_1,
label ? LABEL_SECURITY_INFORMATION : DACL_SECURITY_INFORMATION, &sddl_str,
nullptr));
auto sddl_str_ptr = TakeLocalAlloc(sddl_str);
std::wstring ret = sddl_str_ptr.get();
CHECK(ret.substr(0, 2) == (label ? kSaclPrefix : kDaclPrefix));
return ret.substr(2);
}
} // namespace
TEST(AccessControlListTest, FromPACL) {
auto null_acl = AccessControlList::FromPACL(nullptr);
ASSERT_TRUE(null_acl);
EXPECT_TRUE(null_acl->is_null());
EXPECT_EQ(null_acl->get(), nullptr);
EXPECT_EQ(ConvertAclToSddl(*null_acl), kNullAcl);
ACL dummy_acl = {};
auto invalid_acl = AccessControlList::FromPACL(&dummy_acl);
DWORD error = ::GetLastError();
EXPECT_FALSE(invalid_acl);
EXPECT_EQ(error, DWORD{ERROR_INVALID_ACL});
std::vector<char> compare_acl = ConvertSddlToAcl(kFromPACLTest);
ASSERT_FALSE(compare_acl.empty());
auto test_acl =
AccessControlList::FromPACL(reinterpret_cast<ACL*>(compare_acl.data()));
ASSERT_TRUE(test_acl);
EXPECT_EQ(ConvertAclToSddl(*test_acl), kFromPACLTest);
}
TEST(AccessControlListTest, FromMandatoryLabel) {
auto acl = AccessControlList::FromMandatoryLabel(0, 0, 0);
ASSERT_TRUE(acl);
EXPECT_EQ(ConvertAclToSddl(*acl, true), kUntrustedLabel);
acl = AccessControlList::FromMandatoryLabel(SECURITY_MANDATORY_SYSTEM_RID, 0,
0);
ASSERT_TRUE(acl);
EXPECT_EQ(ConvertAclToSddl(*acl, true), kSystemLabel);
acl = AccessControlList::FromMandatoryLabel(
SECURITY_MANDATORY_SYSTEM_RID, OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
0);
ASSERT_TRUE(acl);
EXPECT_EQ(ConvertAclToSddl(*acl, true), kSystemLabelInherit);
acl = AccessControlList::FromMandatoryLabel(
SECURITY_MANDATORY_SYSTEM_RID, 0,
SYSTEM_MANDATORY_LABEL_NO_WRITE_UP | SYSTEM_MANDATORY_LABEL_NO_READ_UP |
SYSTEM_MANDATORY_LABEL_NO_EXECUTE_UP);
ASSERT_TRUE(acl);
EXPECT_EQ(ConvertAclToSddl(*acl, true), kSystemLabelPolicy);
acl = AccessControlList::FromMandatoryLabel(
SECURITY_MANDATORY_SYSTEM_RID, OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE,
SYSTEM_MANDATORY_LABEL_NO_WRITE_UP | SYSTEM_MANDATORY_LABEL_NO_READ_UP |
SYSTEM_MANDATORY_LABEL_NO_EXECUTE_UP);
ASSERT_TRUE(acl);
EXPECT_EQ(ConvertAclToSddl(*acl, true), kSystemLabelInheritPolicy);
}
TEST(AccessControlListTest, Empty) {
AccessControlList acl;
EXPECT_FALSE(acl.is_null());
ACL* acl_ptr = acl.get();
ASSERT_NE(acl_ptr, nullptr);
EXPECT_EQ(acl_ptr->AceCount, 0);
EXPECT_EQ(acl_ptr->AclSize, sizeof(ACL));
EXPECT_EQ(acl_ptr->AclRevision, ACL_REVISION);
EXPECT_TRUE(ConvertAclToSddl(acl).empty());
AccessControlList acl_clone = acl.Clone();
EXPECT_NE(acl.get(), acl_clone.get());
EXPECT_TRUE(ConvertAclToSddl(acl_clone).empty());
}
TEST(AccessControlListTest, ExplicitAccessEntry) {
constexpr DWORD FakeAccess = 0x12345678U;
constexpr DWORD FakeInherit = 0x87654321U;
Sid sid(WellKnownSid::kWorld);
ExplicitAccessEntry ace(sid, SecurityAccessMode::kGrant, FakeAccess,
FakeInherit);
EXPECT_EQ(sid, ace.sid());
EXPECT_EQ(SecurityAccessMode::kGrant, ace.mode());
EXPECT_EQ(FakeAccess, ace.access_mask());
EXPECT_EQ(FakeInherit, ace.inheritance());
ExplicitAccessEntry ace_clone = ace.Clone();
EXPECT_EQ(ace.sid(), ace_clone.sid());
EXPECT_NE(ace.sid().GetPSID(), ace_clone.sid().GetPSID());
EXPECT_EQ(ace.mode(), ace_clone.mode());
EXPECT_EQ(ace.access_mask(), ace_clone.access_mask());
EXPECT_EQ(ace.inheritance(), ace_clone.inheritance());
ExplicitAccessEntry ace_known(WellKnownSid::kSelf,
SecurityAccessMode::kRevoke, ~FakeAccess,
~FakeInherit);
EXPECT_EQ(Sid(WellKnownSid::kSelf), ace_known.sid());
EXPECT_EQ(SecurityAccessMode::kRevoke, ace_known.mode());
EXPECT_EQ(~FakeAccess, ace_known.access_mask());
EXPECT_EQ(~FakeInherit, ace_known.inheritance());
}
TEST(AccessControlListTest, SetEntries) {
AccessControlList acl;
std::vector<ExplicitAccessEntry> ace_list;
EXPECT_TRUE(acl.SetEntries(ace_list));
EXPECT_EQ(ConvertAclToSddl(acl), L"");
ace_list.emplace_back(Sid(WellKnownSid::kWorld), SecurityAccessMode::kGrant,
EVENT_ALL_ACCESS, 0);
EXPECT_TRUE(acl.SetEntries(ace_list));
EXPECT_EQ(ConvertAclToSddl(acl), kEvent);
ace_list.emplace_back(Sid(WellKnownSid::kLocalSystem),
SecurityAccessMode::kDeny, EVENT_MODIFY_STATE,
CONTAINER_INHERIT_ACE | OBJECT_INHERIT_ACE);
EXPECT_TRUE(acl.SetEntries(ace_list));
EXPECT_EQ(ConvertAclToSddl(acl), kEventWithSystemInherit);
ace_list.emplace_back(Sid(WellKnownSid::kWorld), SecurityAccessMode::kRevoke,
EVENT_MODIFY_STATE, 0);
EXPECT_TRUE(acl.SetEntries(ace_list));
EXPECT_EQ(ConvertAclToSddl(acl), kEventSystemOnlyInherit);
AccessControlList acl_clone = acl.Clone();
EXPECT_NE(acl.get(), acl_clone.get());
EXPECT_EQ(ConvertAclToSddl(acl_clone), kEventSystemOnlyInherit);
}
TEST(AccessControlListTest, SetEntry) {
AccessControlList acl;
EXPECT_TRUE(acl.SetEntry(Sid(WellKnownSid::kWorld),
SecurityAccessMode::kGrant, READ_CONTROL, 0));
EXPECT_EQ(ConvertAclToSddl(acl), kEventReadControl);
EXPECT_TRUE(acl.SetEntry(Sid(WellKnownSid::kWorld),
SecurityAccessMode::kGrant, EVENT_MODIFY_STATE, 0));
EXPECT_EQ(ConvertAclToSddl(acl), kEventReadControlModify);
EXPECT_TRUE(acl.SetEntry(Sid(WellKnownSid::kWorld), SecurityAccessMode::kSet,
EVENT_ALL_ACCESS, 0));
EXPECT_EQ(ConvertAclToSddl(acl), kEvent);
EXPECT_TRUE(acl.SetEntry(Sid(WellKnownSid::kLocalSystem),
SecurityAccessMode::kDeny, EVENT_MODIFY_STATE,
CONTAINER_INHERIT_ACE | OBJECT_INHERIT_ACE));
EXPECT_EQ(ConvertAclToSddl(acl), kEventWithSystemInherit);
EXPECT_TRUE(acl.SetEntry(Sid(WellKnownSid::kWorld),
SecurityAccessMode::kRevoke, EVENT_ALL_ACCESS, 0));
EXPECT_EQ(ConvertAclToSddl(acl), kEventSystemOnlyInherit);
}
TEST(AccessControlListTest, SetEntriesError) {
AccessControlList acl;
std::vector<ExplicitAccessEntry> ace_list;
ace_list.emplace_back(Sid(WellKnownSid::kWorld), SecurityAccessMode::kGrant,
EVENT_ALL_ACCESS, 0);
EXPECT_TRUE(acl.SetEntries(ace_list));
EXPECT_EQ(ConvertAclToSddl(acl), kEvent);
// ACL has a maximum capacity of 2^16-1 bytes or 2^16-1 ACEs. Force a fail.
while (ace_list.size() < 0x10000) {
auto sid =
Sid::FromSddlString(L"S-1-5-1234-" + NumberToWString(ace_list.size()));
ASSERT_TRUE(sid);
ace_list.emplace_back(*sid, SecurityAccessMode::kGrant, GENERIC_ALL, 0);
}
::SetLastError(0);
bool result = acl.SetEntries(ace_list);
DWORD error = ::GetLastError();
EXPECT_FALSE(result);
EXPECT_EQ(error, DWORD{ERROR_INVALID_PARAMETER});
}
TEST(AccessControlListTest, Clear) {
AccessControlList acl;
EXPECT_TRUE(acl.SetEntry(Sid(WellKnownSid::kWorld),
SecurityAccessMode::kGrant, READ_CONTROL, 0));
EXPECT_EQ(acl.get()->AceCount, 1);
acl.Clear();
ASSERT_NE(acl.get(), nullptr);
EXPECT_EQ(acl.get()->AceCount, 0);
}
} // namespace base::win