Modificare una password utente di autenticazione di SQL Server (OLE DB)
In questo esempio viene illustrato come usare OLE DB per modificare la password di un account utente con l'autenticazione di SQL Server.
Importante
Se possibile, usare l'autenticazione di Windows. Se non è disponibile, agli utenti verrà richiesto di immettere le credenziali in fase di esecuzione. Evitare di archiviare le credenziali in un file. Se è necessario rendere persistenti le credenziali, è consigliabile crittografarle usando l'API di crittografia Win32.
Esempio
Prima di eseguire la compilazione, aggiornare il codice C++ per specificare l'ID utente, la vecchia password e quella nuova.
In questa applicazione viene eseguita la connessione all'istanza predefinita di SQL Server nel computer in uso. In alcuni sistemi operativi Windows sarà necessario modificare (local) o (localhost) impostando il valore sul nome dell'istanza di SQL Server. Per connettersi a un'istanza denominata, modificare la stringa di connessione da L"(local)" in L"(local)\\nome", dove nome rappresenta l'istanza denominata. Per impostazione predefinita, SQL Server Express viene installato in un'istanza denominata. Verificare che nella variabile di ambiente INCLUDE sia presente la directory che contiene sqlncli.h.
Eseguire la compilazione con oleaut32.lib ole32.lib.
Per compilare questo esempio, è necessario un account utente con autenticazione di SQL Server per il quale si conosce la password. Per consentire gli account di accesso con autenticazione di SQL Server, aprire SQL Server Management Studio, fare clic con il pulsante destro del mouse sul nodo Server in Esplora oggetti, quindi scegliere Proprietà. Selezionare Sicurezza e abilitare la modalità di autenticazione di SQL Server e di Windows. Per aggiungere un account utente in un ambiente con autenticazione di SQL Server, fare clic con il pulsante destro del mouse sul nodo Sicurezza in Esplora oggetti, quindi scegliere Aggiungi.
Il server nel quale verrà eseguito l'esempio deve disporre di almeno un account di accesso abilitato per l'autenticazione di SQL Server. Deve inoltre consentire gli account di accesso con autenticazione di SQL Server.
// compile with: ole32.lib oleaut32.lib
void InitializeAndEstablishConnection();
#define STATUSDUMP(status) case status : wprintf(L"status"); break;
#define UNICODE
#define DBINITCONSTANTS
#define INITGUID
#include <assert.h>
#include <windows.h>
#include <stdio.h>
#include <stddef.h>
#include <IOSTREAM>
#include <cguid.h>
#include <oledb.h>
#include <oledberr.h>
#include <SQLNCLI.h>
LPMALLOC pMalloc = NULL;
IDBInitialize * pIDBInitialize = NULL;
HRESULT hr;
void DumpErrorInfo (IUnknown* pObjectWithError, REFIID IID_InterfaceWithError);
void DumpErrorInfo (IUnknown* pObjectWithError, REFIID IID_InterfaceWithError, BOOL &has_sql_errors);
int main() {
// All the initialization activities in a separate function.
InitializeAndEstablishConnection();
if ( FAILED( pIDBInitialize->Uninitialize() ) )
// Uninitialize is not required, but fails if an interface was not released.
printf("Problem uninitializing.\n");
pIDBInitialize->Release();
CoUninitialize();
};
void InitializeAndEstablishConnection() {
IDBProperties * pIDBProperties = NULL;
const ULONG nInitProps = 4;
DBPROP InitProperties[nInitProps];
const ULONG nSSInitProps = 1;
DBPROP SSInitProperties[nSSInitProps];
const ULONG nPropSet = 2;
DBPROPSET rgInitPropSet[nPropSet];
// Initialize the COM library.
CoInitialize(NULL);
CoGetMalloc(1, &pMalloc);
CLSID clsid;
CLSIDFromProgID(L"SQLNCLI11", &clsid);
// Obtain access to the SQLOLEDB provider.
hr = CoCreateInstance( clsid, NULL, CLSCTX_INPROC_SERVER, IID_IDBInitialize, (void **) &pIDBInitialize);
if (FAILED(hr))
printf("Failed in CoCreateInstance().\n");
// Initialize the property values needed to establish the connection.
for (int i = 0; i < nInitProps; i++)
VariantInit(&InitProperties[i].vValue);
// Specify database name.
InitProperties[0].dwPropertyID = DBPROP_INIT_CATALOG;
InitProperties[0].vValue.vt = VT_BSTR;
// Change the following line to use any database on your server
InitProperties[0].vValue.bstrVal = SysAllocString(L"master");
InitProperties[0].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[0].colid = DB_NULLID;
InitProperties[1].dwPropertyID = DBPROP_AUTH_USERID;
InitProperties[1].vValue.vt = VT_BSTR;
// Modify the following line to add the user ID of a SQL Server Authentication account on your server
InitProperties[1].vValue.bstrVal = SysAllocString(L"");
InitProperties[1].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[1].colid = DB_NULLID;
InitProperties[2].dwPropertyID = DBPROP_AUTH_PASSWORD;
InitProperties[2].vValue.vt = VT_BSTR;
// Modify the following line to add the new SQL Server Authentication password
InitProperties[2].vValue.bstrVal = SysAllocString(L"");
InitProperties[2].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[2].colid = DB_NULLID;
InitProperties[3].dwPropertyID = DBPROP_INIT_DATASOURCE;
InitProperties[3].vValue.vt = VT_BSTR;
InitProperties[3].vValue.bstrVal = SysAllocString(L"(local)");
InitProperties[3].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[3].colid = DB_NULLID;
SSInitProperties[0].dwPropertyID = SSPROP_AUTH_OLD_PASSWORD;
SSInitProperties[0].vValue.vt = VT_BSTR;
// Modify the following line to specify the existing SQL Server Authentication password
SSInitProperties[0].vValue.bstrVal = SysAllocString(L"");
SSInitProperties[0].dwOptions = DBPROPOPTIONS_REQUIRED;
SSInitProperties[0].colid = DB_NULLID;
rgInitPropSet[0].guidPropertySet = DBPROPSET_DBINIT;
rgInitPropSet[0].cProperties = nInitProps;
rgInitPropSet[0].rgProperties = InitProperties;
rgInitPropSet[1].guidPropertySet = DBPROPSET_SQLSERVERDBINIT;
rgInitPropSet[1].cProperties = nSSInitProps;
rgInitPropSet[1].rgProperties = SSInitProperties;
// Set initialization properties.
hr = pIDBInitialize->QueryInterface( IID_IDBProperties, (void **)&pIDBProperties);
if (FAILED(hr))
printf("Failed to obtain IDBProperties interface.\n");
hr = pIDBProperties->SetProperties( nPropSet, rgInitPropSet);
if (FAILED(hr))
printf("Failed to set initialization properties.\n");
pIDBProperties->Release();
// establish connection to the data source.
DWORD now = GetTickCount();
if ( FAILED(pIDBInitialize->Initialize()) ) {
printf("Problem in initializing.\n");
DumpErrorInfo(pIDBInitialize, IID_IDBInitialize);
}
DWORD tookms = GetTickCount() - now;
printf("Connection took %d ms.\n", tookms);
}
// DumpErrorInfo queries SQLOLEDB error interfaces, retrieving available status
// or error information. This version is called when SQL Server errors are not expected.
void DumpErrorInfo (IUnknown* pObjectWithError, REFIID IID_InterfaceWithError) {
BOOL has_sql_errors;
DumpErrorInfo (pObjectWithError, IID_InterfaceWithError, has_sql_errors);
}
// DumpErrorInfo queries SQLOLEDB error interfaces, retrieving available status
// or error information. This version is called when an SQL Server error could occur.
void DumpErrorInfo (IUnknown* pObjectWithError, REFIID IID_InterfaceWithError, BOOL &has_sql_errors ) {
// Interfaces used in the example.
IErrorInfo * pIErrorInfoAll = NULL;
IErrorInfo * pIErrorInfoRecord = NULL;
IErrorRecords * pIErrorRecords = NULL;
ISupportErrorInfo * pISupportErrorInfo = NULL;
ISQLErrorInfo * pISQLErrorInfo = NULL;
ISQLServerErrorInfo * pISQLServerErrorInfo = NULL;
// Number of error records.
ULONG nRecs;
ULONG nRec;
// Basic error information from GetBasicErrorInfo.
ERRORINFO errorinfo;
// IErrorInfo values.
BSTR bstrDescription;
BSTR bstrSource;
// ISQLErrorInfo parameters.
BSTR bstrSQLSTATE;
LONG lNativeError;
// ISQLServerErrorInfo parameter pointers.
SSERRORINFO * pSSErrorInfo = NULL;
OLECHAR * pSSErrorStrings = NULL;
// Hard-code an English (United States) locale for the example.
DWORD MYLOCALEID = 0x0409;
has_sql_errors = 0;
// Only ask for error information if the interface supports it.
if (FAILED(pObjectWithError->QueryInterface(IID_ISupportErrorInfo, (void**) &pISupportErrorInfo)))
wprintf(L"SupportErrorErrorInfo interface not supported\n");
else if (FAILED(pISupportErrorInfo->InterfaceSupportsErrorInfo(IID_InterfaceWithError)))
wprintf(L"InterfaceWithError interface not supported\n");
// Do not test the return of GetErrorInfo. It can succeed and return
// a NULL pointer in pIErrorInfoAll. Simply test the pointer.
GetErrorInfo(0, &pIErrorInfoAll);
// Test to see if it's a valid OLE DB IErrorInfo interface exposing a list of records.
if (pIErrorInfoAll != NULL) {
if (SUCCEEDED(pIErrorInfoAll->QueryInterface(IID_IErrorRecords, (void**) &pIErrorRecords))) {
pIErrorRecords->GetRecordCount(&nRecs);
// Within each record, retrieve information from each of the defined interfaces.
for (nRec = 0; nRec < nRecs; nRec++) {
ULONG errorno = nRecs - nRec - 1;
// From IErrorRecords, get the HRESULT and a reference to the ISQLErrorInfo interface.
pIErrorRecords->GetBasicErrorInfo(errorno, &errorinfo);
pIErrorRecords->GetCustomErrorObject(errorno,IID_ISQLErrorInfo, (IUnknown**) &pISQLErrorInfo);
// Display the HRESULT, then use the ISQLErrorInfo.
wprintf(L"HRESULT:\t%#X\n", errorinfo.hrError);
if (pISQLErrorInfo != NULL) {
pISQLErrorInfo->GetSQLInfo(&bstrSQLSTATE, &lNativeError);
// Display SQLSTATE and native error values.
wprintf(L"SQLSTATE:\t%s\nNative Error:\t%ld\n", bstrSQLSTATE, lNativeError);
// SysFree BSTR references.
SysFreeString(bstrSQLSTATE);
// Get the ISQLServerErrorInfo interface from
// ISQLErrorInfo before releasing the reference.
pISQLErrorInfo->QueryInterface(IID_ISQLServerErrorInfo, (void**) &pISQLServerErrorInfo);
pISQLErrorInfo->Release();
}
// Test to ensure the reference is valid, then get error information from ISQLServerErrorInfo.
if (pISQLServerErrorInfo != NULL) {
pISQLServerErrorInfo->GetErrorInfo(&pSSErrorInfo, &pSSErrorStrings);
// ISQLServerErrorInfo::GetErrorInfo succeeds even when it
// has nothing to return. Test the pointers before using.
if (pSSErrorInfo) {
// Display the state and severity from the returned
// information. The error message comes from
// IErrorInfo::GetDescription.
wprintf(L"Error state:\t%d\nSeverity:\t%d\n", pSSErrorInfo->bState, pSSErrorInfo->bClass);
wprintf(L"Procedure:\t%s\nLine:\t%d\n", pSSErrorInfo->pwszProcedure, pSSErrorInfo->wLineNumber);
has_sql_errors++;
// IMalloc::Free needed to release references on returned values.
pMalloc->Free(pSSErrorStrings);
pMalloc->Free(pSSErrorInfo);
}
pISQLServerErrorInfo->Release();
}
if (SUCCEEDED(pIErrorRecords->GetErrorInfo(errno, MYLOCALEID, &pIErrorInfoRecord))) {
// Get the source and description (error message) from the record's IErrorInfo.
pIErrorInfoRecord->GetSource(&bstrSource);
pIErrorInfoRecord->GetDescription(&bstrDescription);
if (bstrSource != NULL) {
wprintf(L"Source:\t\t%s\n", bstrSource);
SysFreeString(bstrSource);
}
if (bstrDescription != NULL) {
wprintf(L"Error message:\t%s\n", bstrDescription);
SysFreeString(bstrDescription);
}
pIErrorInfoRecord->Release();
}
}
pIErrorRecords->Release();
}
else {
// IErrorInfo is valid; get the source and
// description to see what it is.
pIErrorInfoAll->GetSource(&bstrSource);
pIErrorInfoAll->GetDescription(&bstrDescription);
if (bstrSource != NULL) {
wprintf(L"Source:\t\t%s\n", bstrSource);
SysFreeString(bstrSource);
}
if (bstrDescription != NULL) {
wprintf(L"Error message:\t%s\n", bstrDescription);
SysFreeString(bstrDescription);
}
}
pIErrorInfoAll->Release();
}
else
wprintf(L"GetErrorInfo failed.\n");
if (pISupportErrorInfo != NULL)
pISupportErrorInfo->Release();
}