Enhance certificate check

PowerEditor/src/MISC/Common/Common.cpp

@@ -34,12 +34,8 @@
 #include "Common.h"
 #include "../Utf8.h"
 
-
 WcharMbcsConvertor* WcharMbcsConvertor::_pSelf = new WcharMbcsConvertor;
 
-
-
-
 void printInt(int int2print)
 {
 	TCHAR str[32];

PowerEditor/src/MISC/Common/verifySignedfile.cpp

@@ -0,0 +1,259 @@
+// This file is part of Notepad++ project
+// Copyright (C)2003 Don HO <don.h@free.fr>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// Note that the GPL places important restrictions on "derived works", yet
+// it does not provide a detailed definition of that term.  To avoid
+// misunderstandings, we consider an application to constitute a
+// "derivative work" for the purpose of this license if it does any of the
+// following:
+// 1. Integrates source code from Notepad++.
+// 2. Integrates/includes/aggregates Notepad++ into a proprietary executable
+//    installer, such as those produced by InstallShield.
+// 3. Links to a library or executes a program that does any of the above.
+//
+// This program 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 for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+
+// VerifyDLL.cpp : Verification of an Authenticode signed DLL
+//
+
+#include <memory>
+#include <windows.h>
+#include <wintrust.h>
+#include <softpub.h>
+#include <wincrypt.h>
+#include <sensapi.h>
+#include <iomanip>
+#include "VerifySignedFile.h"
+#include "Common.h"
+
+using namespace std;
+
+bool VerifySignedLibrary(const wstring& filepath,
+                         const wstring& cert_key_id_hex,
+                         const wstring& cert_subject,
+                         const wstring& cert_display_name)
+{
+	wstring display_name;
+	wstring key_id_hex;
+	wstring subject;
+
+	wstring dmsg(TEXT("VerifyLibrary: "));
+	dmsg += filepath;
+	dmsg += TEXT("\n");
+	
+	OutputDebugString(dmsg.c_str());
+
+	////////////////////// Signature verification
+
+	// Initialize the WINTRUST_FILE_INFO structure.
+	LPCWSTR pwszfilepath = filepath.c_str();
+	WINTRUST_FILE_INFO file_data = { 0 };
+	file_data.cbStruct = sizeof(WINTRUST_FILE_INFO);
+	file_data.pcwszFilePath = pwszfilepath;
+
+	// Initialise WinTrust data	
+	WINTRUST_DATA winTEXTrust_data = { 0 };
+	winTEXTrust_data.cbStruct = sizeof(winTEXTrust_data);
+	winTEXTrust_data.dwUIChoice          = WTD_UI_NONE;	         // do not display optionnal dialog boxes
+	winTEXTrust_data.dwUnionChoice       = WTD_CHOICE_FILE;        // we are not checking catalog signed files
+	winTEXTrust_data.dwStateAction       = WTD_STATEACTION_VERIFY; // only checking
+	winTEXTrust_data.fdwRevocationChecks = WTD_REVOKE_WHOLECHAIN;  // verify the whole certificate chain
+	winTEXTrust_data.pFile               = &file_data;
+
+#if defined( VerifySignedLibrary_DISABLE_REVOCATION_CHECK )
+	winTEXTrust_data.fdwRevocationChecks = WTD_REVOKE_NONE;
+	OutputDebugString(TEXT("VerifyLibrary: certificate revocation disabled at compile time\n"));
+#else
+	// if offline, revocation is not checked
+	// depending of windows version, this may introduce a latency on offline systems
+	DWORD netstatus;
+	QOCINFO oci;
+	oci.dwSize = sizeof(oci);
+	CONST TCHAR* msftTEXTest_site = TEXT("http://www.msfncsi.com/ncsi.txt");
+	bool online = false;
+	online = (0 != IsNetworkAlive(&netstatus) );
+	online = online && ( 0 == GetLastError());
+	online = online && (0 == IsDestinationReachable(msftTEXTest_site, &oci));
+	if (!online)
+	{
+		winTEXTrust_data.fdwRevocationChecks = WTD_REVOKE_NONE;
+		OutputDebugString(TEXT("VerifyLibrary: system is offline - certificate revocation wont be checked\n"));
+	}
+#endif
+
+	// Verify signature and cert-chain validity
+	GUID policy = WINTRUST_ACTION_GENERIC_VERIFY_V2;
+	LONG vtrust = ::WinVerifyTrust(NULL, &policy, &winTEXTrust_data );
+	
+	// Post check cleanup
+	winTEXTrust_data.dwStateAction = WTD_STATEACTION_CLOSE;
+	LONG t2 = ::WinVerifyTrust(NULL, &policy, &winTEXTrust_data);	
+    
+	if (vtrust)
+	{
+		OutputDebugString(TEXT("VerifyLibrary: trust verification failed\n"));
+		return false;
+	}
+
+	if (t2)
+	{
+		OutputDebugString(TEXT("VerifyLibrary: error encountered while cleaning up after WinVerifyTrust\n"));
+		return false;
+	}
+
+	////////////////////// Certificate verification
+	
+	HCERTSTORE        hStore      = nullptr;
+	HCRYPTMSG         hMsg        = nullptr;
+	PCMSG_SIGNER_INFO pSignerInfo = nullptr;
+	DWORD dwEncoding, dwContentType, dwFormatType;
+	DWORD dwSignerInfo = 0L;
+	bool status        = true;
+
+	try {
+		BOOL result = ::CryptQueryObject(CERT_QUERY_OBJECT_FILE, filepath.c_str(),
+										 CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED, CERT_QUERY_FORMAT_FLAG_BINARY, 0,
+										 &dwEncoding, &dwContentType, &dwFormatType,
+										 &hStore, &hMsg, NULL
+		);
+		if (!result)
+		{
+			throw wstring( TEXT("Checking certificate of ") ) + filepath + TEXT(" : ") + GetLastErrorAsString(GetLastError());
+		}
+
+		// Get signer information size.
+		result = ::CryptMsgGetParam(hMsg, CMSG_SIGNER_INFO_PARAM, 0, NULL, &dwSignerInfo);
+		if (!result)
+		{			
+			throw wstring( TEXT("CryptMsgGetParam first call: ")) + GetLastErrorAsString(GetLastError());
+		}
+
+		// Get Signer Information.
+		pSignerInfo = (PCMSG_SIGNER_INFO)LocalAlloc(LPTR, dwSignerInfo);
+		if (NULL == pSignerInfo )
+		{
+			throw wstring( TEXT("Failed to allocate memory for signature processing"));
+		}
+
+		result = CryptMsgGetParam(hMsg, CMSG_SIGNER_INFO_PARAM, 0, (PVOID)pSignerInfo, &dwSignerInfo);
+		if (!result)
+		{
+			throw wstring( TEXT("CryptMsgGetParam: ")) + GetLastErrorAsString(GetLastError());
+		}
+
+		// Get the signer certificate from temporary certificate store.	
+		CERT_INFO cert_info = { 0 };
+		cert_info.Issuer       = pSignerInfo->Issuer;
+		cert_info.SerialNumber = pSignerInfo->SerialNumber;
+		PCCERT_CONTEXT context = ::CertFindCertificateInStore( hStore, X509_ASN_ENCODING | PKCS_7_ASN_ENCODING, 0, CERT_FIND_SUBJECT_CERT, (PVOID)&cert_info, NULL);
+		if (!context)
+		{
+			throw wstring( TEXT("Certificate context: ")) + GetLastErrorAsString(GetLastError());
+		}
+
+		// Getting the full subject				
+		auto subject_sze = ::CertNameToStr(X509_ASN_ENCODING, &context->pCertInfo->Subject, CERT_X500_NAME_STR, NULL, 0);
+		if (subject_sze <= 1)
+		{
+			throw wstring(TEXT("Getting x509 field size problem."));
+		}
+
+		std::unique_ptr<TCHAR[]> subject_buffer(new TCHAR[subject_sze]);
+		if (::CertNameToStr(X509_ASN_ENCODING, &context->pCertInfo->Subject, CERT_X500_NAME_STR, subject_buffer.get(), subject_sze) <= 1)
+		{
+			throw wstring(TEXT("Failed to get x509 filed infos from certificate."));
+		}
+		subject = subject_buffer.get();
+
+		// Getting key_id 
+		DWORD key_id_sze = 0;
+		if (!::CertGetCertificateContextProperty( context, CERT_KEY_IDENTIFIER_PROP_ID, NULL, &key_id_sze))
+		{
+			throw wstring( TEXT("x509 property not found")) + GetLastErrorAsString(GetLastError());
+		}
+
+		std::unique_ptr<BYTE[]> key_id_buff( new BYTE[key_id_sze] );
+		if (!::CertGetCertificateContextProperty( context, CERT_KEY_IDENTIFIER_PROP_ID, key_id_buff.get(), &key_id_sze))
+		{
+			throw wstring( TEXT("Getting certificate property problem.")) + GetLastErrorAsString(GetLastError());
+		}
+
+		wstringstream ss;
+		for (unsigned i = 0; i < key_id_sze; i++)
+		{
+			ss << std::uppercase << std::setfill(TCHAR('0')) << std::setw(2) << std::hex 
+			   << key_id_buff[i];
+		}
+		key_id_hex = ss.str();
+		wstring dbg = key_id_hex + TEXT("\n");
+		OutputDebugString( dbg.c_str() );
+
+		// Getting the display name			
+		auto sze = ::CertGetNameString( context, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0, NULL, NULL, 0);
+		if (sze <= 1)
+		{
+			throw wstring( TEXT("Getting data size problem.")) + GetLastErrorAsString(GetLastError());
+		}
+		
+		// Get display name.
+		std::unique_ptr<TCHAR[]> display_name_buffer( new TCHAR[sze] );
+		if (::CertGetNameString( context, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0, NULL, display_name_buffer.get(), sze) <= 1)
+		{
+			throw wstring( TEXT("Cannot get certificate info.")) + GetLastErrorAsString(GetLastError());
+		}
+		display_name = display_name_buffer.get();
+
+	} catch (wstring s) {
+		::MessageBox(NULL, TEXT("DLL signature verification failed"), s.c_str(), MB_ICONERROR);
+		OutputDebugString(TEXT("VerifyLibrary: error while getting certificate informations\n"));
+		status = false;
+	} catch (...) {
+		// Unknown error
+		OutputDebugString(TEXT("VerifyLibrary: error while getting certificate informations\n"));
+		throw wstring( TEXT("Unknown exception occured. ")) + GetLastErrorAsString(GetLastError());
+	}
+
+	// fields verifications
+	if ( status && !cert_display_name.empty() && cert_display_name != display_name )
+	{
+		status = false;
+		OutputDebugString(TEXT("VerifyLibrary: Invalid certificate display name\n"));
+	}
+
+	if ( status && !cert_subject.empty() && subject != subject)
+	{
+		status = false;
+		OutputDebugString(TEXT("VerifyLibrary: Invalid certificate subject\n"));
+	}
+
+	if ( status && !cert_key_id_hex.empty() && cert_key_id_hex != key_id_hex )
+	{
+		status = false;
+		OutputDebugString(TEXT("VerifyLibrary: Invalid certificate key id\n"));
+	}
+
+	// Clean up.
+	
+	if (hStore != NULL)       CertCloseStore(hStore, 0);
+	if (hMsg   != NULL)       CryptMsgClose(hMsg);
+	if (pSignerInfo != NULL)  LocalFree(pSignerInfo);
+
+	return status;
+
+	////////////////////////
+}
+
+#undef VerifySignedLibrary_DISABLE_REVOCATION_CHECK

PowerEditor/src/MISC/Common/verifySignedfile.h

@@ -0,0 +1,39 @@
+
+
+#pragma once
+
+//#define VerifySignedLibrary_DISABLE_REVOCATION_CHECK "Dont check certificat revocation"
+
+/*
+* Verifies an Authenticde DLL signature and ownership
+*
+* Parameters:
+*  @param filepath        path to the DLL file to examine
+*  @param cert_display_name if specified, the signing certificate display name to compare to. Ignored if set to "", (weak comparison)
+*  @param cert_subject    if specified, the full signing certificate subject name. Ignored if set to "" (strong comparison)
+*  @param cert_key_id_hex if specified, the signing certificate key id (fingerprint), Ignored if set to "" (very strong comparison)
+*
+* @return true if the verification was positive, false if it was negative of encountered some error
+*
+* Dependencies:
+*  This function uses 3 APIs: WinTrust, CryptoAPI, SENS API
+*  It requires to link on : wintrust.lib, crypt32.lib (or crypt64.lib depending on the compilation target) and sensapi.lib
+*  Those functions are available on Windows starting with Windows-XP
+*
+* Limitations:
+*  Certificate revocation checking requires an access to Internet.
+*  The functions checks for connectivity and will disable revocation checking if the machine is offline or if Microsoft
+*  connectivity checking site is not reachable (supposely implying we are on an airgapped network).
+*  Depending on Windows version, this test will be instantaneous (Windows 8 and up) or may take a few seconds.
+*  This behaviour can be disabled by setting a define at compilation time.
+*  If macro VerifySignedLibrary_DISABLE_REVOCATION_CHECK is defined, the revocation
+*  state of the certificates will *not* be checked.
+*
+*/
+
+#include <string>
+
+bool VerifySignedLibrary(const std::wstring& filepath,
+                         const std::wstring& key_id_hex,
+                         const std::wstring& cert_subject,
+                         const std::wstring& display_name);

PowerEditor/src/ScitillaComponent/ScintillaEditView.cpp

@@ -25,13 +25,13 @@
 // along with this program; if not, write to the Free Software
 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-
+#include <memory>
 #include <shlwapi.h>
 #include "ScintillaEditView.h"
 #include "Parameters.h"
 #include "Sorters.h"
 #include "tchar.h"
-#include <memory>
+#include "verifySignedFile.h"
 
 using namespace std;
 
@@ -152,6 +152,11 @@ LanguageName ScintillaEditView::langNames[L_EXTERNAL+1] = {
 //const int MASK_GREEN = 0x00FF00;
 //const int MASK_BLUE  = 0x0000FF;
 
+const generic_string scintilla_signer_display_name = TEXT("Notepad++");
+const generic_string scintilla_signer_subject = TEXT("C=FR, S=Ile-de-France, L=Saint Cloud, O=\"Notepad++\", CN=\"Notepad++\"");
+const generic_string scintilla_signer_key_id = TEXT("42C4C5846BB675C74E2B2C90C69AB44366401093");
+
+
 int getNbDigits(int aNum, int base)
 {
 	int nbChiffre = 1;
@@ -175,12 +180,20 @@ int getNbDigits(int aNum, int base)
 }
 
 TCHAR moduleFileName[1024];
+
 HMODULE loadSciLexerDll()
 {
 	generic_string sciLexerPath = getSciLexerFullPathName(moduleFileName, 1024);
 
-	if (not isCertificateValidated(sciLexerPath, TEXT("Notepad++")))
+	if (not VerifySignedLibrary(sciLexerPath, scintilla_signer_key_id, scintilla_signer_subject, scintilla_signer_display_name))
+	{
+		::MessageBox(NULL,
+			TEXT("Authenticode check failed: signature or signing certificate are not recognized"),
+			TEXT("Library verification failed"),
+			MB_OK | MB_ICONERROR);
 		return nullptr;
+	}
+
 	return ::LoadLibrary(sciLexerPath.c_str());
 }
 

PowerEditor/visual.net/notepadPlus.vs2015.vcxproj

@@ -109,7 +109,7 @@
     </ClCompile>
     <Link>
       <AdditionalOptions>/fixed:no %(AdditionalOptions)</AdditionalOptions>
-      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;wintrust.lib;Sensapi.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <ShowProgress>LinkVerboseLib</ShowProgress>
       <OutputFile>$(OutDir)notepad++.exe</OutputFile>
       <Version>1.0</Version>
@@ -146,7 +146,7 @@
     </ClCompile>
     <Link>
       <AdditionalOptions>/fixed:no %(AdditionalOptions)</AdditionalOptions>
-      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;wintrust.lib;Sensapi.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <ShowProgress>LinkVerboseLib</ShowProgress>
       <OutputFile>$(OutDir)notepad++.exe</OutputFile>
       <Version>1.0</Version>
@@ -188,7 +188,7 @@
       <WarningVersion>18</WarningVersion>
     </ClCompile>
     <Link>
-      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;wintrust.lib;Sensapi.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <ShowProgress>LinkVerboseLib</ShowProgress>
       <OutputFile>$(OutDir)notepad++.exe</OutputFile>
       <Version>1.0</Version>
@@ -239,7 +239,7 @@ copy ..\src\contextMenu.xml ..\bin\contextMenu.xml
       <WarningVersion>18</WarningVersion>
     </ClCompile>
     <Link>
-      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>comctl32.lib;shlwapi.lib;shell32.lib;Oleacc.lib;Dbghelp.lib;Version.lib;Crypt32.lib;wintrust.lib;Sensapi.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <ShowProgress>LinkVerboseLib</ShowProgress>
       <OutputFile>$(OutDir)notepad++.exe</OutputFile>
       <Version>1.0</Version>
@@ -269,6 +269,7 @@ copy ..\src\contextMenu.xml ..\bin64\contextMenu.xml
   <ItemGroup>
     <ClCompile Include="..\src\MISC\Common\LongRunningOperation.cpp" />
     <ClCompile Include="..\src\MISC\Common\mutex.cpp" />
+    <ClCompile Include="..\src\MISC\Common\verifySignedfile.cpp" />
     <ClCompile Include="..\src\MISC\md5\md5Dlgs.cpp" />
     <ClCompile Include="..\src\WinControls\AboutDlg\AboutDlg.cpp" />
     <ClCompile Include="..\src\WinControls\AnsiCharPanel\ansiCharPanel.cpp" />
@@ -534,6 +535,7 @@ copy ..\src\contextMenu.xml ..\bin64\contextMenu.xml
     <ClInclude Include="..\src\MISC\Common\LongRunningOperation.h" />
     <ClInclude Include="..\src\MISC\Common\mutex.h" />
     <ClInclude Include="..\src\MISC\Common\mutex.hxx" />
+    <ClInclude Include="..\src\MISC\Common\verifySignedfile.h" />
     <ClInclude Include="..\src\MISC\md5\md5.h" />
     <ClInclude Include="..\src\MISC\md5\md5Dlgs.h" />
     <ClInclude Include="..\src\MISC\md5\md5Dlgs_rc.h" />