/
XSEC_tests.cpp
1594 lines (1422 loc) · 50.9 KB
/
XSEC_tests.cpp
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/*
XSEC library
Copyright (c) 2021 Yury Strozhevsky <yury@strozhevsky.com>
Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "pch.h"
#include "CppUnitTest.h"
#include "./lib/index.h"
#include <tuple>
#include <filesystem>
#include <authz.h>
using namespace Microsoft::VisualStudio::CppUnitTestFramework;
using namespace XSEC;
//********************************************************************************
std::tuple<BOOL, std::vector<DWORD>, std::vector<DWORD>, std::vector<std::string>> check_access(
const std::wstring name,
const HANDLE& token,
const XSEC::XSD& sd,
DWORD desired_access,
bool zero_mapping = false,
std::optional<std::vector<OBJECT_TYPE_LIST>> object_type_list = std::nullopt,
std::optional<XSEC::XSID> self = std::nullopt
)
{
#pragma region Initial variables
BOOL check_result = FALSE;
PRIVILEGE_SET privileges = { 0 };
DWORD privileges_length = sizeof(privileges);
BOOL GenerateOnClose = FALSE;
GENERIC_MAPPING mapping;
#pragma endregion
#pragma region Set a correct "mapping" values
if(zero_mapping)
mapping = { 0x00 };
else
{
mapping = { 0xFFFFFFFF };
mapping.GenericRead = FILE_GENERIC_READ;
mapping.GenericWrite = FILE_GENERIC_WRITE;
mapping.GenericExecute = FILE_GENERIC_EXECUTE;
mapping.GenericAll = FILE_ALL_ACCESS;
}
#pragma endregion
#pragma region Initialize values related to "object list"
std::vector<OBJECT_TYPE_LIST> object_list_value = object_type_list.value_or(std::vector<OBJECT_TYPE_LIST>{});
GUID zero = { 0x00000000, 0x0000, 0x0000, { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } };
if(object_list_value.size() == 0)
{
// The object list must have at least one element
// identifying the root object itself
object_list_value.push_back({
0,
0,
&zero
});
}
#pragma endregion
#pragma region Initialize "result values"
size_t size = object_list_value.size();
std::vector<DWORD> granted_access(size, 0);
std::vector<DWORD> access_status(size, 0);
#pragma endregion
#pragma region Initialize correct "PrincipalSelf" substitute value
XSEC::bin_t bin_self;
PSID sid_self = NULL;
if(self)
{
bin_self = (XSEC::bin_t)self.value();
sid_self = bin_self.data();
}
#pragma endregion
#pragma region Convert security descriptor into binary format
auto bin = (XSEC::bin_t)sd;
#pragma endregion
#pragma region Make an impersonation token from primary
HANDLE dup_token;
if(FALSE == DuplicateTokenEx(token, MAXIMUM_ALLOWED, nullptr, SecurityDelegation, TokenImpersonation, &dup_token))
throw std::exception("AccessCheck: cannot duplicate token");
#pragma endregion
#pragma region Check access
check_result = AccessCheckByTypeResultListAndAuditAlarmByHandle(
L"XSEC Tests",
nullptr,
dup_token,
L"Test security descriptor",
name.c_str(),
(PSECURITY_DESCRIPTOR)bin.data(),
sid_self,
desired_access,
AuditEventObjectAccess,
AUDIT_ALLOW_NO_PRIVILEGE,
object_list_value.data(),
object_list_value.size(),
&mapping,
FALSE,
granted_access.data(),
access_status.data(),
&GenerateOnClose
);
if(FALSE == check_result)
{
std::stringstream stream;
stream << "AccessCheck: error during a check, #" << GetLastError() << "\n";
throw std::exception(stream.str().c_str());
}
#pragma endregion
std::vector<std::string> granted_access_string;
std::transform(granted_access.begin(), granted_access.end(), std::back_inserter(granted_access_string), [](DWORD value) -> std::string { return std::bitset<32>(value).to_string(); });
return std::make_tuple(check_result, granted_access, access_status, granted_access_string);
}
//********************************************************************************
BOOL WINAPI CheckCallback(AUTHZ_CLIENT_CONTEXT_HANDLE hAuthzClientContext, PACE_HEADER pAce, PVOID pArgs, PBOOL pbAceApplicable)
{
*pbAceApplicable = TRUE;
return TRUE;
}
//********************************************************************************
std::tuple<BOOL, std::vector<DWORD>, std::vector<DWORD>, std::vector<std::string>> check_access_authz(
const std::wstring name,
const HANDLE& token,
const XSEC::XSD& sd,
DWORD desired_access,
bool zero_mapping = false,
std::optional<std::vector<OBJECT_TYPE_LIST>> object_type_list = std::nullopt,
std::optional<XSEC::XSID> self = std::nullopt
)
{
#pragma region Initial variables
BOOL check_result = FALSE;
PRIVILEGE_SET privileges = { 0 };
DWORD privileges_length = sizeof(privileges);
BOOL GenerateOnClose = FALSE;
GENERIC_MAPPING mapping;
#pragma endregion
#pragma region Set a correct "mapping" values
if(zero_mapping)
mapping = { 0x00 };
else
{
mapping = { 0xFFFFFFFF };
mapping.GenericRead = FILE_GENERIC_READ;
mapping.GenericWrite = FILE_GENERIC_WRITE;
mapping.GenericExecute = FILE_GENERIC_EXECUTE;
mapping.GenericAll = FILE_ALL_ACCESS;
}
#pragma endregion
#pragma region Initialize values related to "object list"
std::vector<OBJECT_TYPE_LIST> object_list_value = object_type_list.value_or(std::vector<OBJECT_TYPE_LIST>{});
GUID zero = { 0x00000000, 0x0000, 0x0000, { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } };
if(object_list_value.size() == 0)
{
// The object list must have at least one element
// identifying the root object itself
object_list_value.push_back({
0,
0,
&zero
});
}
#pragma endregion
#pragma region Initialize "result values"
size_t size = object_list_value.size();
std::vector<DWORD> granted_access(size, 0);
std::vector<DWORD> access_status(size, 0);
std::vector<DWORD> sacl_eval_results(size, 0);
std::vector<DWORD> errors(size, 0);
#pragma endregion
#pragma region Initialize correct "PrincipalSelf" substitute value
XSEC::bin_t bin_self;
PSID sid_self = NULL;
if(self)
{
bin_self = (XSEC::bin_t)self.value();
sid_self = bin_self.data();
}
#pragma endregion
#pragma region Convert security descriptor into binary format
auto bin = (XSEC::bin_t)sd;
#pragma endregion
#pragma region Make an impersonation token from primary
HANDLE dup_token;
if(FALSE == DuplicateTokenEx(token, MAXIMUM_ALLOWED, nullptr, SecurityDelegation, TokenImpersonation, &dup_token))
throw std::exception("AccessCheck: cannot duplicate token");
#pragma endregion
#pragma region Check access
AUTHZ_RESOURCE_MANAGER_HANDLE AuthzResMgrHandle = NULL;
AUTHZ_CLIENT_CONTEXT_HANDLE AuthzClientHandle = NULL;
LUID ZeroLuid = { 0, 0 };
AUTHZ_ACCESS_REQUEST AccessRequest = {
desired_access,
sid_self,
object_list_value.data(),
object_list_value.size(),
NULL
};
AUTHZ_ACCESS_REPLY AccessReply = { 0 };
AccessReply.ResultListLength = object_list_value.size();
AccessReply.GrantedAccessMask = granted_access.data();
AccessReply.SaclEvaluationResults = sacl_eval_results.data();
AccessReply.Error = errors.data();
if(!AuthzInitializeResourceManager(
AUTHZ_RM_FLAG_NO_AUDIT,
NULL, //CheckCallback,
NULL,
NULL,
NULL,
&AuthzResMgrHandle
))
{
throw std::exception("AuthzInitializeResourceManager: error");
}
if(!AuthzInitializeContextFromToken(
0,
dup_token,
AuthzResMgrHandle,
NULL,
ZeroLuid,
NULL,
&AuthzClientHandle
))
{
throw std::exception("AuthzInitializeContextFromToken: error");
}
check_result = AuthzAccessCheck(
0,
AuthzClientHandle,
&AccessRequest,
NULL,
(PSECURITY_DESCRIPTOR)bin.data(),
NULL,
0,
&AccessReply,
NULL
);
if(FALSE == check_result)
{
std::stringstream stream;
stream << "AccessCheck: error during a check, #" << GetLastError() << "\n";
throw std::exception(stream.str().c_str());
}
#pragma endregion
std::vector<std::string> granted_access_string;
std::transform(granted_access.begin(), granted_access.end(), std::back_inserter(granted_access_string), [](DWORD value) -> std::string { return std::bitset<32>(value).to_string(); });
return std::make_tuple(check_result, granted_access, access_status, granted_access_string);
}
//********************************************************************************
namespace XSECTests
{
TEST_CLASS(XSECTests)
{
public:
#pragma region Common variables
XSID fiction_owner{ L"S-1-5-21-3522493417-3251241581-1305895453-513" }; // Fiction owner (in order to exclude additional "common access rights" in case owner are equal with token's owner)
XSID fiction_group{ L"S-1-5-21-3522493417-3251241581-1305895453-514" };
#pragma endregion
TEST_CLASS_INITIALIZE(SetupMethod)
{
CoInitialize(NULL);
HANDLE token;
if(!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY | TOKEN_ADJUST_PRIVILEGES, &token))
throw std::exception("XSEC Test: cannot get process token");
// In order to have audit message generation function working we need to set "SeAuditPrivilege"
// in the PROCESS token, NOT in a thread token. So, even if the access check would be
// against a context from thread token the "SeAuditPrivilege" MUST be set in PROCESS token.
if(FALSE == XTOKEN::ChangePrivileges({ L"SeAuditPrivilege" }, token))
throw std::exception("XSEC Test: cannot set necessary privileges");
CloseHandle(token);
}
TEST_CLASS_CLEANUP(ClearMethod)
{
CoUninitialize();
}
TEST_METHOD(BASIC)
{
auto token = XTOKEN::Create(XSID::CurrentUser);
#pragma region The "null DACL"
// If a security descriptor has no DACL at all (null DACL) then all SIDs allowed
auto [result1, granted_access1, access_status1, granted_access_string1] = check_access(
L"The 'null DACL'",
token,
{ fiction_owner },
FILE_ALL_ACCESS
);
Assert::AreEqual(granted_access1[0], (DWORD)FILE_ALL_ACCESS);
#pragma endregion
#pragma region Empty DACL
// If a security descriptor has an "empty DACL" (DACL exists, but has no ACEs) then no SIDs allowed
auto [result2, granted_access2, access_status2, granted_access_string2] = check_access(
L"Empty DACL",
token,
{ fiction_owner, { std::initializer_list<XACE>{} } },
FILE_ALL_ACCESS
);
Assert::AreEqual(granted_access2[0], (DWORD)0);
// When we set "SeTakeOwnershipPrivilege" in token we can get WRITE_OWNER access even to this "unaccesable" SD
auto [result2_1, granted_access2_1, access_status2_1, granted_access_string2_1] = check_access(
L"Empty DACL but with SeTakeOwnershipPrivilege",
XTOKEN::Create(
XSID::CurrentUser,
XSID::Everyone,
{{ L"SeTakeOwnershipPrivilege" }}
),
{ fiction_owner, { std::initializer_list<XACE>{} } },
WRITE_OWNER
);
Assert::AreEqual(granted_access2_1[0], (DWORD)WRITE_OWNER);
// For an owner in SD there are always "READ_CONTROL + WRITE_DAC" access.
// So, even if here we have "empty DACL" owner can get "READ_CONTROL + WRITE_DAC" access rights.
auto [result2_2, granted_access2_2, access_status2_2, granted_access_string2_2] = check_access(
L"Empty DACL but with special access rights for SD owner",
XTOKEN::Create(
fiction_owner
),
{ fiction_owner, { std::initializer_list<XACE>{} } },
READ_CONTROL | WRITE_DAC
);
Assert::AreEqual(granted_access2_2[0], (DWORD)(READ_CONTROL | WRITE_DAC));
#pragma endregion
#pragma region Common denied ACE
// In a "common case" denied ACEs must be before "allowed" ACEs and should have non-zero access mask
auto [result3, granted_access3, access_status3, granted_access_string3] = check_access(
L"Common denied ACE",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group
),
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
XSID::CurrentUser,
(DWORD)FILE_READ_ACCESS
),
// The "Everyone" group cannot be using as a "all users in the world" always.
// If the "Everyone" group would not exist in token's SIDs then
// "Everyone" would not be considered during access checking.
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)(FILE_READ_ACCESS | FILE_WRITE_ACCESS)
),
XACCESS_ALLOWED_ACE(
fiction_group,
(DWORD)(FILE_READ_ACCESS | FILE_WRITE_ACCESS | FILE_APPEND_DATA)
)
}}
},
FILE_READ_ACCESS | FILE_WRITE_ACCESS | FILE_APPEND_DATA
);
// In fact access for this particular token to this particular SD was denied.
// It is because "desired access = FILE_READ_ACCESS | FILE_WRITE_ACCESS | FILE_APPEND_DATA",
// but for user's SID some access was denied (FILE_READ_ACCESS). So, even if "granted access" has a value
// in general access was denied (not all access from "desired access" was satisfied).
Assert::AreEqual(granted_access3[0], (DWORD)(FILE_WRITE_ACCESS | FILE_APPEND_DATA));
#pragma endregion
#pragma region Denied ACE after allowed
// In case of a wrong ACE order the system access checking function would allow
// all access because the the function meet allow rule first
auto [result4, granted_access4, access_status4, granted_access_string4] = check_access(
L"Denied ACE after allowed",
token,
{
fiction_owner,
{{
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS
),
XACCESS_DENIED_ACE(
XSID::CurrentUser,
(DWORD)FILE_READ_ACCESS
)
}}
},
FILE_READ_ACCESS | FILE_WRITE_ACCESS
);
Assert::AreEqual(granted_access4[0], (DWORD)FILE_READ_ACCESS | FILE_WRITE_ACCESS);
#pragma endregion
#pragma region Denied ACE with zero access mask
// In case of a correct ACE order but when denied ACE has zero access mask system access
// cheching function do not count the denied ACE (the denied ACE deny nothing)
auto [result5, granted_access5, access_status5, granted_access_string5] = check_access(
L"Denied ACE with zero access mask",
token,
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
XSID::CurrentUser,
(DWORD)0
),
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS
)
}}
},
FILE_READ_ACCESS | FILE_WRITE_ACCESS
);
Assert::AreEqual(granted_access5[0], (DWORD)FILE_READ_ACCESS | FILE_WRITE_ACCESS);
#pragma endregion
#pragma region Denied access for group
// In this case there is a "deny rule" for group in token. But the group do not have "SE_GROUP_ENABLED" flag set.
// That is why access checking would not consider the "deny rule" and will grant full access to the SD.
auto [result6, granted_access6, access_status6, granted_access_string6] = check_access(
L"Denied access for group",
XTOKEN::Create(
XSID::CurrentUser,
XSID::Everyone,
{},
{ { fiction_group, (DWORD)0 } }
),
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
fiction_group,
(DWORD)FILE_ALL_ACCESS
),
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS
)
}}
},
FILE_ALL_ACCESS
);
Assert::AreEqual(granted_access6[0], (DWORD)FILE_ALL_ACCESS);
// In order to not allow any user to disable critical groups the group in token must have at least "SE_GROUP_MANDATORY" flag set
auto [result6_1, granted_access6_1, access_status6_1, granted_access_string6_1] = check_access(
L"Denied access for group but with SE_GROUP_MANDATORY flag set",
XTOKEN::Create(
XSID::CurrentUser,
XSID::Everyone,
{},
{ { fiction_group, { SidAndAttributesMeaningDefault, { L"SE_GROUP_MANDATORY" } } } }
),
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
fiction_group,
(DWORD)FILE_ALL_ACCESS
),
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS
)
}}
},
FILE_ALL_ACCESS
);
Assert::AreEqual(granted_access6_1[0], (DWORD)0);
#pragma endregion
#pragma region Inheritence in ACE
auto [result7, granted_access7, access_status7, granted_access_string7] = check_access(
L"Inheritence in ACE",
XTOKEN::Create(
XSID::CurrentUser,
XSID::Everyone,
{},
{ { fiction_group, { SidAndAttributesMeaningDefault, { L"SE_GROUP_MANDATORY" } } } }
),
{
fiction_owner,
{{
// This ACE would not count because it has "INHERIT_ONLY_ACE" flag set
XACCESS_DENIED_ACE(
fiction_group,
(DWORD)FILE_ALL_ACCESS,
{ ByteBitsMeaningAceFlags, { L"INHERIT_ONLY_ACE" } }
),
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS,
{
ByteBitsMeaningAceFlags,
{
L"INHERITED_ACE", // Simple flag representing the ACE was inhirited
L"OBJECT_INHERIT_ACE", // It will be applicable to all descendant files
L"CONTAINER_INHERIT_ACE", // It will be applicable to all descendant folders
L"NO_PROPAGATE_INHERIT_ACE" // If the ACE is inherited by a child object, the system clears the OBJECT_INHERIT_ACE and CONTAINER_INHERIT_ACE flags in the inherited ACE. This prevents the ACE from being inherited by subsequent generations of objects
}
}
)
}}
},
FILE_ALL_ACCESS
);
Assert::AreEqual(granted_access7[0], (DWORD)FILE_ALL_ACCESS);
#pragma endregion
#pragma region Using of "Principal Self SID" in ACE
auto [result8, granted_access8, access_status8, granted_access_string8] = check_access(
L"Using of 'Principal Self SID' in ACE",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group
),
{
fiction_owner,
{{
XACCESS_ALLOWED_ACE(
XSID::PlaceholderPrincipalSelf,
(DWORD)FILE_ALL_ACCESS
)
}}
},
FILE_ALL_ACCESS,
false,
std::nullopt,
fiction_group // The "PrincipalSelf" in all ACEs would be replaced by this SID
);
Assert::AreEqual(granted_access8[0], (DWORD)FILE_ALL_ACCESS);
#pragma endregion
#pragma region Audit: common audit message
// NOTE: in order to generate any audit messages the calling PROCESS token must have "SeAuditPrivilege" enabled.
// In this test we set "SeAuditPrivilege" in process token in "TEST_CLASS_INITIALIZE" function.
// Privileges in the token participating in access checking does not matter.
auto [result9, granted_access9, access_status9, granted_access_string9] = check_access(
L"Audit: common audit message",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group
),
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
XSID::CurrentUser,
(DWORD)FILE_READ_ACCESS
),
XACCESS_ALLOWED_ACE(
fiction_group,
(DWORD)FILE_ALL_ACCESS
)
}},
{{
// Does not matter which flags to put here: if a mask is in "desired access" then logging would be performed.
// In case access was denied (as in this case) it would be "denied message".
XSYSTEM_AUDIT_ACE(
// Even if we put "Everyone" here audit message have a chance to be suspended.
// The audit message would be generated only if the SID from SYSTEM_AUDIT_ACE exists
// in user's token. So, if there is no "Everyone" SID in token then no audit messages
/// would be generated for "XSYSTEM_AUDIT_ACE(Everyone)".
fiction_group,
(DWORD)FILE_WRITE_ACCESS,
{ ByteBitsMeaningAceFlags, { L"SUCCESSFUL_ACCESS_ACE_FLAG", L"FAILED_ACCESS_ACE_FLAG" } }
)
}}
},
FILE_READ_ACCESS | FILE_WRITE_ACCESS
);
Assert::AreEqual(granted_access9[0], (DWORD)FILE_WRITE_ACCESS);
#pragma endregion
#pragma region Audit: missing FAILED_ACCESS_ACE_FLAG flag
auto [result10, granted_access10, access_status10, granted_access_string10] = check_access(
L"Audit: missing FAILED_ACCESS_ACE_FLAG flag",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group
),
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
XSID::CurrentUser,
(DWORD)FILE_READ_ACCESS
),
XACCESS_ALLOWED_ACE(
fiction_group,
(DWORD)FILE_ALL_ACCESS
)
}},
{{
// Audit message would not be generated due to missing "FAILED_ACCESS_ACE_FLAG" flag
XSYSTEM_AUDIT_ACE(
fiction_group,
(DWORD)FILE_WRITE_ACCESS,
{ ByteBitsMeaningAceFlags, { L"SUCCESSFUL_ACCESS_ACE_FLAG" } }
)
}}
},
FILE_READ_ACCESS | FILE_WRITE_ACCESS
);
Assert::AreEqual(granted_access10[0], (DWORD)FILE_WRITE_ACCESS);
#pragma endregion
#pragma region Audit: conditional audit message
auto [result11, granted_access11, access_status11, granted_access_string11] = check_access(
L"Audit: conditional audit message",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group,
{},
{},
std::nullopt,
{
{{L"Title", { L"VP" }}}
}
),
{
fiction_owner,
{{
XACCESS_DENIED_ACE(
XSID::CurrentUser,
(DWORD)FILE_READ_ACCESS
),
XACCESS_ALLOWED_ACE(
fiction_group,
(DWORD)FILE_ALL_ACCESS
)
}},
{{
XSYSTEM_AUDIT_CALLBACK_ACE(
fiction_group,
(DWORD)FILE_WRITE_ACCESS,
XUser(L"Title") == L"VP"
)
}}
},
FILE_READ_ACCESS | FILE_WRITE_ACCESS
);
Assert::AreEqual(granted_access11[0], (DWORD)FILE_WRITE_ACCESS);
#pragma endregion
}
TEST_METHOD(FILE_EXAMPLE)
{
// How system creates DACL for new objects
// https://docs.microsoft.com/en-us/windows/win32/secauthz/dacl-for-a-new-object
#pragma region Check directory exists and remove it if necessary
auto current = std::filesystem::current_path();
if(std::filesystem::exists(current / "inherited"))
std::filesystem::remove_all(current / "inherited");
#pragma endregion
#pragma region Create a sample directory with a default security descriptor
if(!std::filesystem::create_directory(current / "inherited"))
throw std::exception("Cannot make 'inherited' directory");
#pragma endregion
#pragma region Change DACL for the newly created directory
XSD sd{
XSID::CurrentUser,
{{
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS
),
}}
};
bin_t bin = (bin_t)sd;
BOOL result = SetFileSecurity(L"inherited", DACL_SECURITY_INFORMATION, (PSECURITY_DESCRIPTOR)bin.data());
if(FALSE == result)
{
std::stringstream stream;
stream << "Error on changing SD: " << GetLastError();
throw std::exception(stream.str().c_str());
}
#pragma endregion
#pragma region Make a token with "default DACL" and create a subdirectory with the token
auto token = XTOKEN::Create(
fiction_owner,
fiction_group,
{
{ L"SeChangeNotifyPrivilege" } // Bypass traverse checking
},
{ XSID::Everyone }, // Need this group in order to access root directory
std::nullopt,
std::nullopt,
std::nullopt,
std::nullopt,
{},
std::nullopt,
{ {
XACCESS_ALLOWED_ACE(
XSID::Everyone,
(DWORD)FILE_ALL_ACCESS,
{ ByteBitsMeaningAceFlags, { L"OBJECT_INHERIT_ACE", L"CONTAINER_INHERIT_ACE" } }
),
XACCESS_ALLOWED_ACE(
XSID::PlaceholderPrincipalSelf, // Requires separate parameter during access check
{ DwordMeaningFile, { L"GENERIC_ALL" } },
{ ByteBitsMeaningAceFlags, { L"INHERIT_ONLY_ACE", L"OBJECT_INHERIT_ACE", L"CONTAINER_INHERIT_ACE" } }
),
XACCESS_ALLOWED_ACE(
XSID::PlaceholderCreatorOwner, // Substitute with "Owner" from active token
{ DwordMeaningFile, { L"GENERIC_ALL" } },
{ ByteBitsMeaningAceFlags, { L"INHERIT_ONLY_ACE", L"OBJECT_INHERIT_ACE", L"CONTAINER_INHERIT_ACE" } }
),
XACCESS_ALLOWED_ACE(
XSID::PlaceholderCreatorGroup, // Substitute with "PrimaryGroup" from active token
{ DwordMeaningFile, { L"GENERIC_ALL" } },
{ ByteBitsMeaningAceFlags, { L"INHERIT_ONLY_ACE", L"OBJECT_INHERIT_ACE", L"CONTAINER_INHERIT_ACE" } }
),
XACCESS_ALLOWED_ACE(
XSID::PlaceholderOwnerServer, // Disapears from final DACL
{ DwordMeaningFile, { L"GENERIC_ALL" } },
{ ByteBitsMeaningAceFlags, { L"INHERIT_ONLY_ACE", L"OBJECT_INHERIT_ACE", L"CONTAINER_INHERIT_ACE" } }
),
XACCESS_ALLOWED_ACE(
XSID::PlaceholderGroupServer, // Disapears from final DACL
{ DwordMeaningFile, { L"GENERIC_ALL" } },
{ ByteBitsMeaningAceFlags, { L"INHERIT_ONLY_ACE", L"OBJECT_INHERIT_ACE", L"CONTAINER_INHERIT_ACE" } }
)
} }
);
HANDLE dup_token;
if(FALSE == DuplicateTokenEx(token, MAXIMUM_ALLOWED, nullptr, SecurityDelegation, TokenImpersonation, &dup_token))
throw std::exception("Cannot duplicate token");
if(FALSE == SetThreadToken(nullptr, dup_token))
throw std::exception("Cannot set token for thread");
if(!std::filesystem::create_directory(current / "inherited/subdirectory"))
throw std::exception("Cannot make 'inherited' directory");
#pragma region Create a file using "manually made" token
// The "PlaceholderCreatorOwner" and "PlaceholderCreatorGroup" values
// are from "manually made" token. But a system also append values from "process token" somehow.
std::ofstream(current / "inherited/subdirectory/file1.txt");
#pragma endregion
SetThreadToken(nullptr, nullptr); // Set back default token for current thread
#pragma endregion
#pragma region Get security descriptor from newly created file and store it to XML
auto sd_file1 = XSD::GetFromFileObject(L"inherited/subdirectory/file1.txt");
XSave(sd_file1, L"sd_file1.xml");
#pragma endregion
#pragma region Create a new file inside the subfolder using "default values"
// Now on the file we will have a correctly set substitutes for
// "PlaceholderCreatorOwner" and "PlaceholderCreatorGroup".
// NOTE: all these values came from PROCESS token, not from the
// token we manually made before (with default DACL).
std::ofstream(current / "inherited/subdirectory/file2.txt");
#pragma endregion
}
TEST_METHOD(INTEGRITY_CHECK)
{
#pragma region The "null DACL" with low integrity level in token
// Access the security descriptor with "null DACL" (all SIDs allowed), but making a token with "UntrustedMandatoryLevel"
// and at the same time security descriptor has "SystemMandatoryLevel" (with all flags set).
auto [result1, granted_access1, access_status1, granted_access_string1] = check_access(
L"The 'null DACL' with low integrity level in token",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group,
{},
{
{ XSID::UntrustedMandatoryLevel, { SidAndAttributesMeaningDefault, { L"SE_GROUP_INTEGRITY", L"SE_GROUP_INTEGRITY_ENABLED" } }}
}
),
{
fiction_owner,
std::nullopt,
{{
XSYSTEM_MANDATORY_LABEL_ACE(
XSID::SystemMandatoryLevel,
{ DwordMeaningMandatoryLabel, { L"SYSTEM_MANDATORY_LABEL_NO_WRITE_UP", L"SYSTEM_MANDATORY_LABEL_NO_READ_UP", L"SYSTEM_MANDATORY_LABEL_NO_EXECUTE_UP" } }
)
}}
},
FILE_ALL_ACCESS
);
Assert::AreEqual(granted_access1[0], (DWORD)0);
// Same configuration, but with "SYSTEM_MANDATORY_LABEL_NO_READ_UP = 0" in SD and access requested in only FILE_READ_DATA.
// The access would be granted, even for "UntrustedMandatoryLevel" in token.
auto [result1_1, granted_access1_1, access_status1_1, granted_access_string1_1] = check_access(
L"The 'null DACL' with low integrity level in token but with 'SYSTEM_MANDATORY_LABEL_NO_READ_UP = 0'",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group,
{},
{
{ XSID::UntrustedMandatoryLevel, { SidAndAttributesMeaningDefault, { L"SE_GROUP_INTEGRITY", L"SE_GROUP_INTEGRITY_ENABLED" } }}
}
),
{
fiction_owner,
std::nullopt,
{{
XSYSTEM_MANDATORY_LABEL_ACE(
XSID::SystemMandatoryLevel,
{ DwordMeaningMandatoryLabel, { L"SYSTEM_MANDATORY_LABEL_NO_WRITE_UP", L"SYSTEM_MANDATORY_LABEL_NO_EXECUTE_UP" } }
)
}}
},
FILE_READ_DATA
);
Assert::AreEqual(granted_access1_1[0], (DWORD)FILE_READ_DATA);
// Same configuration, but with "SYSTEM_MANDATORY_LABEL_NO_READ_UP = 0" in SD and access requested in only FILE_READ_DATA.
// But in this case in access checking function we do not use "generic rights mapping" and if the "mapping" is not used
// the access check would be performed again using only two integrity levels comparision (no check for "SYSTEM_MANDATORY_LABEL_NO_READ_UP = 0").
auto [result1_2, granted_access1_2, access_status1_2, granted_access_string1_2] = check_access(
L"The 'null DACL' with low integrity level in token but with 'SYSTEM_MANDATORY_LABEL_NO_READ_UP = 0' but without 'mapping'",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group,
{},
{
{ XSID::UntrustedMandatoryLevel, { SidAndAttributesMeaningDefault, { L"SE_GROUP_INTEGRITY", L"SE_GROUP_INTEGRITY_ENABLED" } }}
}
),
{
fiction_owner,
std::nullopt,
{{
XSYSTEM_MANDATORY_LABEL_ACE(
XSID::SystemMandatoryLevel,
{ DwordMeaningMandatoryLabel, { L"SYSTEM_MANDATORY_LABEL_NO_WRITE_UP", L"SYSTEM_MANDATORY_LABEL_NO_EXECUTE_UP" } }
)
}}
},
FILE_READ_DATA,
true // Flag for "not to use generic rights mapping"
);
Assert::AreEqual(granted_access1_2[0], (DWORD)0);
// Same input as in previous case, but now we set 0 to "mandatory policy flags" in token.
// It allows completely bypass any integrity checks and again check would be done for "null DACL" only (all SIDs allowed).
auto [result1_3, granted_access1_3, access_status1_3, granted_access_string1_3] = check_access(
L"The 'null DACL' with low integrity level in token but with 'SYSTEM_MANDATORY_LABEL_NO_READ_UP = 0' but without 'mapping' and 'mandatory policy flags = 0'",
XTOKEN::Create(
XSID::CurrentUser,
fiction_group,
{},
{
{ XSID::UntrustedMandatoryLevel, { SidAndAttributesMeaningDefault, { L"SE_GROUP_INTEGRITY", L"SE_GROUP_INTEGRITY_ENABLED" } }}
},
std::nullopt,
std::nullopt,
std::nullopt,
std::nullopt,
{},
(DWORD)0 // Mandatory policy flags
),
{
fiction_owner,
std::nullopt,
{{
XSYSTEM_MANDATORY_LABEL_ACE(
XSID::SystemMandatoryLevel,
{ DwordMeaningMandatoryLabel, { L"SYSTEM_MANDATORY_LABEL_NO_WRITE_UP", L"SYSTEM_MANDATORY_LABEL_NO_EXECUTE_UP" } }
)
}}
},
FILE_ALL_ACCESS,
true // Flag for "not to use generic rights mapping"
);
Assert::AreEqual(granted_access1_3[0], (DWORD)FILE_ALL_ACCESS);
#pragma endregion
#pragma region Administrative privileges on token with low level
//
// Certain administrative Windows privileges can be assigned to an access token only with at least a high integrity
// level.If the access token integrity level is less than high, then specific administrative privileges are not allowed
// and are removed from the access token (or just set to 0). The administrative privileges associated with a high integrity level are:
// SeCreateTokenPrivilege
// SeTcbPrivilege
// SeTakeOwnershipPrivilege
// SeLoadDriverPrivilege
// SeBackupPrivilege
// SeRestorePrivilege
// SeDebugPrivilege
// SeImpersonatePrivilege
// SeRelabelPrivilege
// SeDelegateSessionUserImpersonatePrivilege
//
auto token = XTOKEN::Create(
XSID::CurrentUser,
fiction_group,
{
{ L"SeCreateTokenPrivilege" },
{ L"SeTcbPrivilege" },
{ L"SeTakeOwnershipPrivilege" },
{ L"SeLoadDriverPrivilege" },
{ L"SeBackupPrivilege" },
{ L"SeRestorePrivilege" },
{ L"SeDebugPrivilege" },
{ L"SeImpersonatePrivilege" },
{ L"SeRelabelPrivilege" },
{ L"SeDelegateSessionUserImpersonatePrivilege" }
},
{
{ XSID::MediumMandatoryLevel, { SidAndAttributesMeaningDefault, { L"SE_GROUP_INTEGRITY", L"SE_GROUP_INTEGRITY_ENABLED" } }}
}
);
DWORD attributes = 0;
for(auto&& element : XTOKEN::GetTokenInfo<TokenPrivileges>(token))
attributes += (DWORD)*element.Attributes;
Assert::AreEqual(attributes, (DWORD)0);