/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include "system.h"
#include <userenv.h>

#include <cassert>
#include <osl/security.h>
#include <osl/diagnose.h>
#include <osl/thread.h>
#include <osl/file.h>
#include <systools/win32/comtools.hxx>
#include <systools/win32/uwinapi.h>
#include <sddl.h>
#include <sal/macros.h>
#include <sal/log.hxx>
#include <o3tl/char16_t2wchar_t.hxx>
#include "secimpl.hxx"

/* To get an impersonation token we need to create an impersonation
   duplicate so every access token has to be created with duplicate
   access rights */

#define TOKEN_DUP_QUERY (TOKEN_QUERY|TOKEN_DUPLICATE)

static bool GetSpecialFolder(rtl_uString **strPath, REFKNOWNFOLDERID rFolder);
// We use LPCTSTR here, because we use it with SE_foo_NAME constants
// which are defined in winnt.h as UNICODE-dependent TEXT("PrivilegeName")
static bool Privilege(LPCTSTR pszPrivilege, bool bEnable);
static bool getUserNameImpl(oslSecurity Security, rtl_uString **strName, bool bIncludeDomain);

oslSecurity SAL_CALL osl_getCurrentSecurity(void)
{
    oslSecurityImpl* pSecImpl = static_cast<oslSecurityImpl *>(malloc(sizeof(oslSecurityImpl)));
    if (pSecImpl)
    {
        pSecImpl->m_pNetResource = nullptr;
        pSecImpl->m_User[0] = '\0';
        pSecImpl->m_hToken = nullptr;
        pSecImpl->m_hProfile = nullptr;
    }
    return pSecImpl;
}

oslSecurityError SAL_CALL osl_loginUser( rtl_uString *strUserName, rtl_uString *strPasswd, oslSecurity *pSecurity )
{
    oslSecurityError ret;

    sal_Unicode*    strUser;
    sal_Unicode*    strDomain = o3tl::toU(_wcsdup(o3tl::toW(rtl_uString_getStr(strUserName))));
    HANDLE  hUserToken;
    LUID luid;

    if (nullptr != (strUser = o3tl::toU(wcschr(o3tl::toW(strDomain), L'/'))))
        *strUser++ = L'\0';
    else
    {
        strUser   = strDomain;
        strDomain = nullptr;
    }

    // this process must have the right: 'act as a part of operatingsystem'
    OSL_ASSERT(LookupPrivilegeValue(nullptr, SE_TCB_NAME, &luid));
    (void) luid;

    if (LogonUserW(o3tl::toW(strUser), strDomain ? o3tl::toW(strDomain) : L"", o3tl::toW(rtl_uString_getStr(strPasswd)),
                  LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT,
                   &hUserToken))
    {
        oslSecurityImpl* pSecImpl = static_cast<oslSecurityImpl *>(malloc(sizeof(oslSecurityImpl)));
        if (pSecImpl)
        {
            pSecImpl->m_pNetResource = nullptr;
            pSecImpl->m_hToken = hUserToken;
            pSecImpl->m_hProfile = nullptr;
            wcscpy(o3tl::toW(pSecImpl->m_User), o3tl::toW(strUser));
        }
        *pSecurity = pSecImpl;
        ret = pSecImpl ? osl_Security_E_None : osl_Security_E_Unknown;
    }
    else
    {
        ret = osl_Security_E_UserUnknown;
    }

    if (strDomain)
        free(strDomain);
    else
        free(strUser);

    return ret;
}

oslSecurityError SAL_CALL osl_loginUserOnFileServer(rtl_uString *strUserName,
                                                    rtl_uString *strPasswd,
                                                    rtl_uString *strFileServer,
                                                    oslSecurity *pSecurity)
{
    oslSecurityError    ret;
    DWORD               err;
    NETRESOURCEW        netResource;
    sal_Unicode*                remoteName;
    sal_Unicode*                userName;

    remoteName  = static_cast<sal_Unicode *>(malloc((rtl_uString_getLength(strFileServer) + rtl_uString_getLength(strUserName) + 4) * sizeof(sal_Unicode)));
    userName    = static_cast<sal_Unicode *>(malloc((rtl_uString_getLength(strFileServer) + rtl_uString_getLength(strUserName) + 2) * sizeof(sal_Unicode)));

    wcscpy(o3tl::toW(remoteName), L"\\\\");
    wcscat(o3tl::toW(remoteName), o3tl::toW(rtl_uString_getStr(strFileServer)));
    wcscat(o3tl::toW(remoteName), L"\\");
    wcscat(o3tl::toW(remoteName), o3tl::toW(rtl_uString_getStr(strUserName)));

    wcscpy(o3tl::toW(userName), o3tl::toW(rtl_uString_getStr(strFileServer)));
    wcscat(o3tl::toW(userName), L"\\");
    wcscat(o3tl::toW(userName), o3tl::toW(rtl_uString_getStr(strUserName)));

    netResource.dwScope         = RESOURCE_GLOBALNET;
    netResource.dwType          = RESOURCETYPE_DISK;
    netResource.dwDisplayType   = RESOURCEDISPLAYTYPE_SHARE;
    netResource.dwUsage         = RESOURCEUSAGE_CONNECTABLE;
    netResource.lpLocalName     = nullptr;
    netResource.lpRemoteName    = o3tl::toW(remoteName);
    netResource.lpComment       = nullptr;
    netResource.lpProvider      = nullptr;

    err = WNetAddConnection2W(&netResource, o3tl::toW(rtl_uString_getStr(strPasswd)), o3tl::toW(userName), 0);

    if ((err == NO_ERROR) || (err == ERROR_ALREADY_ASSIGNED))
    {
        oslSecurityImpl* pSecImpl = static_cast<oslSecurityImpl *>(malloc(sizeof(oslSecurityImpl)));
        if (pSecImpl)
        {
            pSecImpl->m_pNetResource = static_cast<NETRESOURCEW *>(malloc(sizeof(NETRESOURCE)));
            if (pSecImpl->m_pNetResource)
            {
                *pSecImpl->m_pNetResource = netResource;
                pSecImpl->m_hToken = nullptr;
                pSecImpl->m_hProfile = nullptr;
                wcscpy(o3tl::toW(pSecImpl->m_User), o3tl::toW(rtl_uString_getStr(strUserName)));
            }
            else
            {
                free(pSecImpl);
                pSecImpl = nullptr;
            }
        }
        *pSecurity = pSecImpl;

        ret = pSecImpl ? osl_Security_E_None : osl_Security_E_Unknown;
    }
    else
    {
        ret = osl_Security_E_UserUnknown;
    }

    free(remoteName);
    free(userName);

    return ret;
}

sal_Bool SAL_CALL osl_isAdministrator(oslSecurity Security)
{
    if (!Security)
        return false;

    HANDLE                      hImpersonationToken = nullptr;
    PSID                        psidAdministrators;
    SID_IDENTIFIER_AUTHORITY    siaNtAuthority = { SECURITY_NT_AUTHORITY };
    bool                    bSuccess = false;

    /* If Security contains an access token we need to duplicate it to an impersonation
       access token. NULL works with CheckTokenMembership() as the current effective
       impersonation token
     */

    if ( static_cast<oslSecurityImpl*>(Security)->m_hToken )
    {
        if ( !DuplicateToken (static_cast<oslSecurityImpl*>(Security)->m_hToken, SecurityImpersonation, &hImpersonationToken) )
            return false;
    }

    /* CheckTokenMembership() can be used on W2K and higher (NT4 no longer supported by OOo)
       and also works on Vista to retrieve the effective user rights. Just checking for
       membership of Administrators group is not enough on Vista this would require additional
       complicated checks as described in KB article Q118626: http://support.microsoft.com/kb/118626/en-us
    */

    if (AllocateAndInitializeSid(&siaNtAuthority,
                                 2,
                                 SECURITY_BUILTIN_DOMAIN_RID,
                                 DOMAIN_ALIAS_RID_ADMINS,
                                 0, 0, 0, 0, 0, 0,
                                 &psidAdministrators))
    {
        BOOL fSuccess = FALSE;

        if (CheckTokenMembership(hImpersonationToken, psidAdministrators, &fSuccess) && fSuccess)
            bSuccess = true;

        FreeSid(psidAdministrators);
    }

    if (hImpersonationToken)
        CloseHandle(hImpersonationToken);

    return bSuccess;
}

void SAL_CALL osl_freeSecurityHandle(oslSecurity Security)
{
    if (!Security)
        return;

    oslSecurityImpl *pSecImpl = static_cast<oslSecurityImpl*>(Security);

    if (pSecImpl->m_pNetResource != nullptr)
    {
        WNetCancelConnection2W(pSecImpl->m_pNetResource->lpRemoteName, 0, true);

        free(pSecImpl->m_pNetResource->lpRemoteName);
        free(pSecImpl->m_pNetResource);
    }

    if (pSecImpl->m_hToken)
        CloseHandle(pSecImpl->m_hToken);

    if ( pSecImpl->m_hProfile )
        CloseHandle(pSecImpl->m_hProfile);

    free (pSecImpl);
}

sal_Bool SAL_CALL osl_getUserIdent(oslSecurity Security, rtl_uString **strIdent)
{
    if (!Security)
       return false;

    oslSecurityImpl *pSecImpl = static_cast<oslSecurityImpl*>(Security);

    HANDLE hAccessToken = pSecImpl->m_hToken;

    if (hAccessToken == nullptr)
        OpenProcessToken(GetCurrentProcess(), TOKEN_DUP_QUERY, &hAccessToken);

    if (hAccessToken)
    {
        DWORD  nInfoBuffer = 512;
        UCHAR* pInfoBuffer = static_cast<UCHAR *>(malloc(nInfoBuffer));

        while (!GetTokenInformation(hAccessToken, TokenUser,
                                       pInfoBuffer, nInfoBuffer, &nInfoBuffer))
        {
            if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
            {
                if (auto p = static_cast<UCHAR *>(realloc(pInfoBuffer, nInfoBuffer)))
                    pInfoBuffer = p;
                else
                {
                    free(pInfoBuffer);
                    pInfoBuffer = nullptr;
                    break;
                }
            }
            else
            {
                free(pInfoBuffer);
                pInfoBuffer = nullptr;
                break;
            }
        }

        if (pSecImpl->m_hToken == nullptr)
            CloseHandle(hAccessToken);

        if (pInfoBuffer)
        {
            PSID pSid = reinterpret_cast<PTOKEN_USER>(pInfoBuffer)->User.Sid;

            LPWSTR pSidStr = nullptr;
            bool bResult = ConvertSidToStringSidW(pSid, &pSidStr);
            if (bResult)
            {
                rtl_uString_newFromStr(strIdent, o3tl::toU(pSidStr));
                LocalFree(pSidStr);
            }
            else
            {
                const DWORD dwError = GetLastError();
                SAL_WARN(
                    "sal.osl",
                    "ConvertSidToStringSidW failed. GetLastError returned: " << dwError);
            }

            free(pInfoBuffer);

            return bResult;
        }
    }
    else
    {
        DWORD needed = 0;

        WNetGetUserW(nullptr, nullptr, &needed);
        if (needed < 16)
            needed = 16;

        if (auto Ident = static_cast<sal_Unicode *>(malloc(needed*sizeof(sal_Unicode))))
        {
            if (WNetGetUserW(nullptr, o3tl::toW(Ident), &needed) != NO_ERROR)
            {
                wcscpy(o3tl::toW(Ident), L"unknown");
                Ident[7] = L'\0';
            }

            rtl_uString_newFromStr( strIdent, Ident);
            free(Ident);
            return true;
        }
    }
    return false;
}

sal_Bool SAL_CALL osl_getUserName(oslSecurity Security, rtl_uString **strName)
{
    return getUserNameImpl(Security, strName, true);
}

sal_Bool SAL_CALL osl_getShortUserName(oslSecurity Security, rtl_uString **strName)
{
    return getUserNameImpl(Security, strName, false);
}

sal_Bool SAL_CALL osl_getHomeDir(oslSecurity Security, rtl_uString **pustrDirectory)
{
    if (!Security)
        return false;

    rtl_uString *ustrSysDir = nullptr;
    bool bSuccess = false;

    oslSecurityImpl *pSecImpl = static_cast<oslSecurityImpl*>(Security);

    if (pSecImpl->m_pNetResource != nullptr)
    {
        rtl_uString_newFromStr( &ustrSysDir, o3tl::toU(pSecImpl->m_pNetResource->lpRemoteName));

        bSuccess = osl_File_E_None == osl_getFileURLFromSystemPath( ustrSysDir, pustrDirectory );
    }
    else
    {
            bSuccess = GetSpecialFolder(&ustrSysDir, FOLDERID_Documents) &&
                                 (osl_File_E_None == osl_getFileURLFromSystemPath(ustrSysDir, pustrDirectory));
    }

    if ( ustrSysDir )
        rtl_uString_release( ustrSysDir );

    return bSuccess;
}

sal_Bool SAL_CALL osl_getConfigDir(oslSecurity Security, rtl_uString **pustrDirectory)
{
    if (!Security)
        return false;

    bool bSuccess = false;
    oslSecurityImpl *pSecImpl = static_cast<oslSecurityImpl*>(Security);

    if (pSecImpl->m_pNetResource != nullptr)
    {
        rtl_uString *ustrSysDir = nullptr;

        rtl_uString_newFromStr( &ustrSysDir, o3tl::toU(pSecImpl->m_pNetResource->lpRemoteName));
        bSuccess = osl_File_E_None == osl_getFileURLFromSystemPath( ustrSysDir, pustrDirectory);

        if ( ustrSysDir )
            rtl_uString_release( ustrSysDir );
    }
    else
    {
        if (pSecImpl->m_hToken)
        {
            /* not implemented */
            OSL_ASSERT(false);
        }
        else
        {
            rtl_uString *ustrFile = nullptr;
            sal_Unicode sFile[_MAX_PATH];

            if ( !GetSpecialFolder( &ustrFile, FOLDERID_RoamingAppData) )
            {
                OSL_VERIFY(GetWindowsDirectoryW(o3tl::toW(sFile), _MAX_DIR) > 0);

                rtl_uString_newFromStr( &ustrFile, sFile);
            }

            bSuccess = osl_File_E_None == osl_getFileURLFromSystemPath(ustrFile, pustrDirectory);

            if ( ustrFile )
                rtl_uString_release( ustrFile );
        }
    }

    return bSuccess;
}

sal_Bool SAL_CALL osl_loadUserProfile(oslSecurity Security)
{
    /*  CreateProcessAsUser does not load the specified user's profile
        into the HKEY_USERS registry key. This means that access to information
        in the HKEY_CURRENT_USER registry key may not produce results consistent
        with a normal interactive logon.
        It is your responsibility to load the user's registry hive into HKEY_USERS
        with the LoadUserProfile function before calling CreateProcessAsUser.
    */

    RegCloseKey(HKEY_CURRENT_USER);

    if (!Privilege(SE_RESTORE_NAME, true))
        return false;

    bool bOk = false;
    HANDLE hAccessToken = static_cast<oslSecurityImpl*>(Security)->m_hToken;

    /* try to create user profile */
    if ( !hAccessToken )
    {
        /* retrieve security handle if not done before e.g. osl_getCurrentSecurity()
        */
        HANDLE hProcess = GetCurrentProcess();

        if (hProcess != nullptr)
        {
            OpenProcessToken(hProcess, TOKEN_IMPERSONATE, &hAccessToken);
            CloseHandle(hProcess);
        }
    }

    rtl_uString *buffer = nullptr;
    PROFILEINFOW pi;

    getUserNameImpl(Security, &buffer, false);

    ZeroMemory(&pi, sizeof(pi));
    pi.dwSize = sizeof(pi);
    pi.lpUserName = o3tl::toW(rtl_uString_getStr(buffer));
    pi.dwFlags = PI_NOUI;

    if (LoadUserProfileW(hAccessToken, &pi))
    {
        UnloadUserProfile(hAccessToken, pi.hProfile);

        bOk = true;
    }

    rtl_uString_release(buffer);

    if (hAccessToken && (hAccessToken != static_cast<oslSecurityImpl*>(Security)->m_hToken))
        CloseHandle(hAccessToken);

    return bOk;
}

void SAL_CALL osl_unloadUserProfile(oslSecurity Security)
{
    if ( static_cast<oslSecurityImpl*>(Security)->m_hProfile == nullptr )
        return;

    HANDLE hAccessToken = static_cast<oslSecurityImpl*>(Security)->m_hToken;

    if ( !hAccessToken )
    {
        /* retrieve security handle if not done before e.g. osl_getCurrentSecurity()
        */
        HANDLE hProcess = GetCurrentProcess();

        if (hProcess != nullptr)
        {
            OpenProcessToken(hProcess, TOKEN_IMPERSONATE, &hAccessToken);
            CloseHandle(hProcess);
        }
    }

    /* unloading the user profile */
    UnloadUserProfile(hAccessToken, static_cast<oslSecurityImpl*>(Security)->m_hProfile);

    static_cast<oslSecurityImpl*>(Security)->m_hProfile = nullptr;

    if (hAccessToken && (hAccessToken != static_cast<oslSecurityImpl*>(Security)->m_hToken))
        CloseHandle(hAccessToken);
}

static bool GetSpecialFolder(rtl_uString **strPath, REFKNOWNFOLDERID rFolder)
{
    sal::systools::CoTaskMemAllocated<wchar_t> PathW;
    if (SUCCEEDED(SHGetKnownFolderPath(rFolder, KF_FLAG_CREATE, nullptr, &PathW)))
    {
        rtl_uString_newFromStr(strPath, o3tl::toU(PathW));
        return true;
    }

    return false;
}

// We use LPCTSTR here, because we use it with SE_foo_NAME constants
// which are defined in winnt.h as UNICODE-dependent TEXT("PrivilegeName")
static bool Privilege(LPCTSTR strPrivilege, bool bEnable)
{
    HANDLE           hToken;
    TOKEN_PRIVILEGES tp;

    // obtain the processes token
    if (!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_DUP_QUERY, &hToken))
        return false;

    // get the luid
    if (!LookupPrivilegeValue(nullptr, strPrivilege, &tp.Privileges[0].Luid))
        return false;

    tp.PrivilegeCount = 1;

    if (bEnable)
        tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
    else
        tp.Privileges[0].Attributes = 0;

    // enable or disable the privilege
    if (!AdjustTokenPrivileges(hToken, FALSE, &tp, 0, nullptr, nullptr))
        return false;

    if (!CloseHandle(hToken))
        return false;

    return true;
}

static bool getUserNameImpl(oslSecurity Security, rtl_uString **strName,  bool bIncludeDomain)
{
    if (!Security)
        return false;

    oslSecurityImpl *pSecImpl = static_cast<oslSecurityImpl*>(Security);

    HANDLE hAccessToken = pSecImpl->m_hToken;

    if (hAccessToken == nullptr)
        OpenProcessToken(GetCurrentProcess(), TOKEN_DUP_QUERY, &hAccessToken);

    if (hAccessToken)
    {
        DWORD  nInfoBuffer = 512;
        UCHAR* pInfoBuffer = static_cast<UCHAR *>(malloc(nInfoBuffer));

        while (!GetTokenInformation(hAccessToken, TokenUser,
                                       pInfoBuffer, nInfoBuffer, &nInfoBuffer))
        {
            if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
            {
                if (auto p = static_cast<UCHAR *>(realloc(pInfoBuffer, nInfoBuffer)))
                    pInfoBuffer = p;
                else
                {
                    free(pInfoBuffer);
                    pInfoBuffer = nullptr;
                    break;
                }
            }
            else
            {
                free(pInfoBuffer);
                pInfoBuffer = nullptr;
                break;
            }
        }

        if (pSecImpl->m_hToken == nullptr)
            CloseHandle(hAccessToken);

        if (pInfoBuffer)
        {
            sal_Unicode  UserName[128];
            sal_Unicode  DomainName[128];
            sal_Unicode  Name[257];
            DWORD nUserName   = SAL_N_ELEMENTS(UserName);
            DWORD nDomainName = SAL_N_ELEMENTS(DomainName);
            SID_NAME_USE sUse;

            if (LookupAccountSidW(nullptr, reinterpret_cast<PTOKEN_USER>(pInfoBuffer)->User.Sid,
                                    o3tl::toW(UserName), &nUserName,
                                    o3tl::toW(DomainName), &nDomainName, &sUse))
            {
                if (bIncludeDomain)
                {
                    wcscpy(o3tl::toW(Name), o3tl::toW(DomainName));
                    wcscat(o3tl::toW(Name), L"/");
                    wcscat(o3tl::toW(Name), o3tl::toW(UserName));
                }
                else
                {
                    wcscpy(o3tl::toW(Name), o3tl::toW(UserName));
                }

                rtl_uString_newFromStr(strName, Name);
                free(pInfoBuffer);
                return true;
            }
        }
    }
    else
    {
        DWORD needed=0;
        sal_Unicode *pNameW=nullptr;

        WNetGetUserW(nullptr, nullptr, &needed);
        pNameW = static_cast<sal_Unicode *>(malloc (needed*sizeof(sal_Unicode)));
        assert(pNameW); // Don't handle OOM conditions

        if (WNetGetUserW(nullptr, o3tl::toW(pNameW), &needed) == NO_ERROR)
        {
            rtl_uString_newFromStr( strName, pNameW);

            if (pNameW)
                free(pNameW);
            return true;
        }
        else if (pSecImpl->m_User[0] != '\0')
        {
            rtl_uString_newFromStr(strName, o3tl::toU(pSecImpl->m_pNetResource->lpRemoteName));

            if (pNameW)
                free(pNameW);

            return true;
        }

        if (pNameW)
            free(pNameW);
    }

    return false;
}

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