251 lines
8.0 KiB
C++
251 lines
8.0 KiB
C++
/* 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/. */
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <windows.h>
|
|
#include <softpub.h>
|
|
#include <wintrust.h>
|
|
|
|
#include "certificatecheck.h"
|
|
#include "updatecommon.h"
|
|
|
|
static const int ENCODING = X509_ASN_ENCODING | PKCS_7_ASN_ENCODING;
|
|
|
|
/**
|
|
* Checks to see if a file stored at filePath matches the specified info.
|
|
*
|
|
* @param filePath The PE file path to check
|
|
* @param infoToMatch The acceptable information to match
|
|
* @return ERROR_SUCCESS if successful, ERROR_NOT_FOUND if the info
|
|
* does not match, or the last error otherwise.
|
|
*/
|
|
DWORD
|
|
CheckCertificateForPEFile(LPCWSTR filePath,
|
|
CertificateCheckInfo &infoToMatch)
|
|
{
|
|
HCERTSTORE certStore = nullptr;
|
|
HCRYPTMSG cryptMsg = nullptr;
|
|
PCCERT_CONTEXT certContext = nullptr;
|
|
PCMSG_SIGNER_INFO signerInfo = nullptr;
|
|
DWORD lastError = ERROR_SUCCESS;
|
|
|
|
// Get the HCERTSTORE and HCRYPTMSG from the signed file.
|
|
DWORD encoding, contentType, formatType;
|
|
BOOL result = CryptQueryObject(CERT_QUERY_OBJECT_FILE,
|
|
filePath,
|
|
CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED,
|
|
CERT_QUERY_CONTENT_FLAG_ALL,
|
|
0, &encoding, &contentType,
|
|
&formatType, &certStore, &cryptMsg, nullptr);
|
|
if (!result) {
|
|
lastError = GetLastError();
|
|
LOG_WARN(("CryptQueryObject failed. (%d)", lastError));
|
|
goto cleanup;
|
|
}
|
|
|
|
// Pass in nullptr to get the needed signer information size.
|
|
DWORD signerInfoSize;
|
|
result = CryptMsgGetParam(cryptMsg, CMSG_SIGNER_INFO_PARAM, 0,
|
|
nullptr, &signerInfoSize);
|
|
if (!result) {
|
|
lastError = GetLastError();
|
|
LOG_WARN(("CryptMsgGetParam failed. (%d)", lastError));
|
|
goto cleanup;
|
|
}
|
|
|
|
// Allocate the needed size for the signer information.
|
|
signerInfo = (PCMSG_SIGNER_INFO)LocalAlloc(LPTR, signerInfoSize);
|
|
if (!signerInfo) {
|
|
lastError = GetLastError();
|
|
LOG_WARN(("Unable to allocate memory for Signer Info. (%d)", lastError));
|
|
goto cleanup;
|
|
}
|
|
|
|
// Get the signer information (PCMSG_SIGNER_INFO).
|
|
// In particular we want the issuer and serial number.
|
|
result = CryptMsgGetParam(cryptMsg, CMSG_SIGNER_INFO_PARAM, 0,
|
|
(PVOID)signerInfo, &signerInfoSize);
|
|
if (!result) {
|
|
lastError = GetLastError();
|
|
LOG_WARN(("CryptMsgGetParam failed. (%d)", lastError));
|
|
goto cleanup;
|
|
}
|
|
|
|
// Search for the signer certificate in the certificate store.
|
|
CERT_INFO certInfo;
|
|
certInfo.Issuer = signerInfo->Issuer;
|
|
certInfo.SerialNumber = signerInfo->SerialNumber;
|
|
certContext = CertFindCertificateInStore(certStore, ENCODING, 0,
|
|
CERT_FIND_SUBJECT_CERT,
|
|
(PVOID)&certInfo, nullptr);
|
|
if (!certContext) {
|
|
lastError = GetLastError();
|
|
LOG_WARN(("CertFindCertificateInStore failed. (%d)", lastError));
|
|
goto cleanup;
|
|
}
|
|
|
|
if (!DoCertificateAttributesMatch(certContext, infoToMatch)) {
|
|
lastError = ERROR_NOT_FOUND;
|
|
LOG_WARN(("Certificate did not match issuer or name. (%d)", lastError));
|
|
goto cleanup;
|
|
}
|
|
|
|
cleanup:
|
|
if (signerInfo) {
|
|
LocalFree(signerInfo);
|
|
}
|
|
if (certContext) {
|
|
CertFreeCertificateContext(certContext);
|
|
}
|
|
if (certStore) {
|
|
CertCloseStore(certStore, 0);
|
|
}
|
|
if (cryptMsg) {
|
|
CryptMsgClose(cryptMsg);
|
|
}
|
|
return lastError;
|
|
}
|
|
|
|
/**
|
|
* Checks to see if a file stored at filePath matches the specified info.
|
|
*
|
|
* @param certContext The certificate context of the file
|
|
* @param infoToMatch The acceptable information to match
|
|
* @return FALSE if the info does not match or if any error occurs in the check
|
|
*/
|
|
BOOL
|
|
DoCertificateAttributesMatch(PCCERT_CONTEXT certContext,
|
|
CertificateCheckInfo &infoToMatch)
|
|
{
|
|
DWORD dwData;
|
|
LPWSTR szName = nullptr;
|
|
|
|
if (infoToMatch.issuer) {
|
|
// Pass in nullptr to get the needed size of the issuer buffer.
|
|
dwData = CertGetNameString(certContext,
|
|
CERT_NAME_SIMPLE_DISPLAY_TYPE,
|
|
CERT_NAME_ISSUER_FLAG, nullptr,
|
|
nullptr, 0);
|
|
|
|
if (!dwData) {
|
|
LOG_WARN(("CertGetNameString failed. (%d)", GetLastError()));
|
|
return FALSE;
|
|
}
|
|
|
|
// Allocate memory for Issuer name buffer.
|
|
szName = (LPWSTR)LocalAlloc(LPTR, dwData * sizeof(WCHAR));
|
|
if (!szName) {
|
|
LOG_WARN(("Unable to allocate memory for issuer name. (%d)",
|
|
GetLastError()));
|
|
return FALSE;
|
|
}
|
|
|
|
// Get Issuer name.
|
|
if (!CertGetNameStringW(certContext, CERT_NAME_SIMPLE_DISPLAY_TYPE,
|
|
CERT_NAME_ISSUER_FLAG, nullptr, szName, dwData)) {
|
|
LOG_WARN(("CertGetNameString failed. (%d)", GetLastError()));
|
|
LocalFree(szName);
|
|
return FALSE;
|
|
}
|
|
|
|
// If the issuer does not match, return a failure.
|
|
if (!infoToMatch.issuer ||
|
|
wcscmp(szName, infoToMatch.issuer)) {
|
|
LocalFree(szName);
|
|
return FALSE;
|
|
}
|
|
|
|
LocalFree(szName);
|
|
szName = nullptr;
|
|
}
|
|
|
|
if (infoToMatch.name) {
|
|
// Pass in nullptr to get the needed size of the name buffer.
|
|
dwData = CertGetNameString(certContext, CERT_NAME_SIMPLE_DISPLAY_TYPE,
|
|
0, nullptr, nullptr, 0);
|
|
if (!dwData) {
|
|
LOG_WARN(("CertGetNameString failed. (%d)", GetLastError()));
|
|
return FALSE;
|
|
}
|
|
|
|
// Allocate memory for the name buffer.
|
|
szName = (LPWSTR)LocalAlloc(LPTR, dwData * sizeof(WCHAR));
|
|
if (!szName) {
|
|
LOG_WARN(("Unable to allocate memory for subject name. (%d)",
|
|
GetLastError()));
|
|
return FALSE;
|
|
}
|
|
|
|
// Obtain the name.
|
|
if (!(CertGetNameStringW(certContext, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0,
|
|
nullptr, szName, dwData))) {
|
|
LOG_WARN(("CertGetNameString failed. (%d)", GetLastError()));
|
|
LocalFree(szName);
|
|
return FALSE;
|
|
}
|
|
|
|
// If the issuer does not match, return a failure.
|
|
if (!infoToMatch.name ||
|
|
wcscmp(szName, infoToMatch.name)) {
|
|
LocalFree(szName);
|
|
return FALSE;
|
|
}
|
|
|
|
// We have a match!
|
|
LocalFree(szName);
|
|
}
|
|
|
|
// If there were any errors we would have aborted by now.
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
* Verifies the trust of the specified file path.
|
|
*
|
|
* @param filePath The file path to check.
|
|
* @return ERROR_SUCCESS if successful, or the last error code otherwise.
|
|
*/
|
|
DWORD
|
|
VerifyCertificateTrustForFile(LPCWSTR filePath)
|
|
{
|
|
// Setup the file to check.
|
|
WINTRUST_FILE_INFO fileToCheck;
|
|
ZeroMemory(&fileToCheck, sizeof(fileToCheck));
|
|
fileToCheck.cbStruct = sizeof(WINTRUST_FILE_INFO);
|
|
fileToCheck.pcwszFilePath = filePath;
|
|
|
|
// Setup what to check, we want to check it is signed and trusted.
|
|
WINTRUST_DATA trustData;
|
|
ZeroMemory(&trustData, sizeof(trustData));
|
|
trustData.cbStruct = sizeof(trustData);
|
|
trustData.pPolicyCallbackData = nullptr;
|
|
trustData.pSIPClientData = nullptr;
|
|
trustData.dwUIChoice = WTD_UI_NONE;
|
|
trustData.fdwRevocationChecks = WTD_REVOKE_NONE;
|
|
trustData.dwUnionChoice = WTD_CHOICE_FILE;
|
|
trustData.dwStateAction = 0;
|
|
trustData.hWVTStateData = nullptr;
|
|
trustData.pwszURLReference = nullptr;
|
|
// no UI
|
|
trustData.dwUIContext = 0;
|
|
trustData.pFile = &fileToCheck;
|
|
|
|
GUID policyGUID = WINTRUST_ACTION_GENERIC_VERIFY_V2;
|
|
// Check if the file is signed by something that is trusted.
|
|
LONG ret = WinVerifyTrust(nullptr, &policyGUID, &trustData);
|
|
if (ERROR_SUCCESS == ret) {
|
|
// The hash that represents the subject is trusted and there were no
|
|
// verification errors. No publisher nor time stamp chain errors.
|
|
LOG(("The file \"%ls\" is signed and the signature was verified.",
|
|
filePath));
|
|
return ERROR_SUCCESS;
|
|
}
|
|
|
|
DWORD lastError = GetLastError();
|
|
LOG_WARN(("There was an error validating trust of the certificate for file"
|
|
" \"%ls\". Returned: %d. (%d)", filePath, ret, lastError));
|
|
return ret;
|
|
}
|