Exemple de programme C : Opérations du magasin de certificats
L’exemple suivant illustre un certain nombre d’opérations courantes de magasin de certificats , ainsi que les tâches et fonctions CryptoAPI suivantes :
- Ouverture et fermeture des magasins de mémoire et système à l’aide de CertOpenStore et de CertCloseStore.
- Duplication d’un magasin ouvert à l’aide de CertDuplicateStore.
- La recherche dans stocke les certificats qui répondent à certains critères à l’aide de CertFindCertificateInStore.
- Création d’un contexte de certificat à partir de la partie encodée d’un certificat existant à l’aide de CertCreateCertificateContext.
- Ajout d’un certificat récupéré à un magasin en mémoire à l’aide de CertAddCertificateContextToStore.
- Ajout d’un lien vers un certificat à un magasin à l’aide de CertAddCertificateLinkToStore.
- Enregistrement du magasin en mémoire dans un fichier sur disque.
- Ouverture et fermeture d’un magasin de certificats basé sur des fichiers.
Cet exemple utilise la fonction MyHandleError. Le code de cette fonction est inclus dans l’exemple. Le code pour cette fonction auxiliaire et d’autres fonctions auxiliaires est également répertorié sous usage général Fonctions.
Cet exemple utilise la fonction CreateMyDACL , définie dans la rubrique Création d’un fichier DACL , pour garantir que le fichier ouvert est créé avec une liste DACL appropriée.
Cet exemple crée un magasin de certificats en mémoire. Un magasin système est ouvert et dupliqué. Un certificat est récupéré à partir de la banque système. Un nouveau certificat est créé à partir de la partie encodée du certificat récupéré. Le certificat récupéré est ajouté au magasin de mémoire. Un deuxième certificat est récupéré à partir de Mon magasin et un lien vers ce certificat est ajouté au magasin de mémoire. Le certificat et le lien sont ensuite récupérés à partir du magasin de mémoire et la mémoire est enregistrée sur le disque. Tous les magasins et fichiers sont fermés. Ensuite, le magasin de fichiers est rouvert et une recherche du lien de certificat est effectuée. Le succès de ce programme dépend de la disponibilité d’un Magasin My. Ce magasin doit inclure un certificat avec l’objet « Insert_cert_subject_name1 » et un deuxième certificat avec l’objet « Insert_cert_subject_name2 ». Les noms des sujets doivent être remplacés par les noms des sujets de certificat connus pour se trouver dans la boutique My.
#include <stdio.h>
#include <windows.h>
#include <Wincrypt.h>
#define MY_ENCODING_TYPE (PKCS_7_ASN_ENCODING | X509_ASN_ENCODING)
void MyHandleError(char *s);
void main(void)
{
//--------------------------------------------------------------------
// Copyright (C) Microsoft. All rights reserved.
// Declare and initialize variables.
HCERTSTORE hSystemStore; // System store handle
HCERTSTORE hMemoryStore; // Memory store handle
HCERTSTORE hDuplicateStore; // Handle for a store to be
// created
// as a duplicate of an open
// store
PCCERT_CONTEXT pDesiredCert = NULL; // Set to NULL for the first
// call to
// CertFindCertificateInStore
PCCERT_CONTEXT pCertContext;
HANDLE hStoreFileHandle ; // Output file handle
LPWSTR pszFileName = L"TestStor.sto"; // Output file name
SECURITY_ATTRIBUTES sa; // For DACL
//-------------------------------------------------------------------
// Open a new certificate store in memory.
if(hMemoryStore = CertOpenStore(
CERT_STORE_PROV_MEMORY, // Memory store
0, // Encoding type
// not used with a memory store
NULL, // Use the default provider
0, // No flags
NULL)) // Not needed
{
printf("Opened a memory store. \n");
}
else
{
MyHandleError( "Error opening a memory store.");
}
//-------------------------------------------------------------------
// Open the My system store using CertOpenStore.
if(hSystemStore = CertOpenStore(
CERT_STORE_PROV_SYSTEM, // System store will be a
// virtual store
0, // Encoding type not needed
// with this PROV
NULL, // Accept the default HCRYPTPROV
CERT_SYSTEM_STORE_CURRENT_USER,
// Set the system store location in the
// registry
L"MY")) // Could have used other predefined
// system stores
// including Trust, CA, or Root
{
printf("Opened the MY system store. \n");
}
else
{
MyHandleError( "Could not open the MY system store.");
}
//-------------------------------------------------------------------
// Create a duplicate of the My store.
if(hDuplicateStore = CertDuplicateStore(hSystemStore))
{
printf("The MY store is duplicated.\n");
}
else
{
printf("Duplication of the MY store failed.\n.");
}
//-------------------------------------------------------------------
// Close the duplicate store.
if(hDuplicateStore)
CertCloseStore(
hDuplicateStore,
CERT_CLOSE_STORE_CHECK_FLAG);
//-------------------------------------------------------------------
// Get a certificate that has the string "Insert_cert_subject_name1"
// in its subject.
if(pDesiredCert=CertFindCertificateInStore(
hSystemStore,
MY_ENCODING_TYPE, // Use X509_ASN_ENCODING
0, // No dwFlags needed
CERT_FIND_SUBJECT_STR, // Find a certificate with a
// subject that matches the
// string in the next parameter
L"Insert_cert_subject_name1", // The Unicode string to be found
// in a certificate's subject
NULL)) // NULL for the first call to the
// function
// In all subsequent
// calls, it is the last pointer
// returned by the function
{
printf("The desired certificate was found. \n");
}
else
{
MyHandleError("Could not find the desired certificate.");
}
//-------------------------------------------------------------------
// pDesiredCert is a pointer to a certificate with a subject that
// includes the string "Insert_cert_subject_name1", the string is
// passed as parameter #5 to the function.
//------------------------------------------------------------------
// Create a new certificate from the encoded part of
// an available certificate.
if(pCertContext = CertCreateCertificateContext(
MY_ENCODING_TYPE , // Encoding type
pDesiredCert->pbCertEncoded, // Encoded data from
// the certificate retrieved
pDesiredCert->cbCertEncoded)) // Length of the encoded data
{
printf("A new certificate has been created.\n");
}
else
{
MyHandleError("A new certificate could not be created.");
}
//-------------------------------------------------------------------
// Add the certificate from the My store to the new memory store.
if(CertAddCertificateContextToStore(
hMemoryStore, // Store handle
pDesiredCert, // Pointer to a certificate
CERT_STORE_ADD_USE_EXISTING,
NULL))
{
printf("Certificate added to the memory store. \n");
}
else
{
MyHandleError("Could not add the certificate "
"to the memory store.");
}
//-------------------------------------------------------------------
// Find a different certificate in the My store, and add to it a link
// to the memory store.
//-------------------------------------------------------------------
// Find the certificate context just added to the memory store.
if(pDesiredCert)
CertFreeCertificateContext(pDesiredCert);
if(pDesiredCert=CertFindCertificateInStore(
hSystemStore,
MY_ENCODING_TYPE, // Use X509_ASN_ENCODING
0, // no dwFlags needed
CERT_FIND_SUBJECT_STR, // Find a certificate with a
// subject that matches the
// string in the next parameter
L"Insert_cert_subject_name2",// The Unicode string to be found
// in a certificate's subject
NULL)) // NULL for the first call to the
// function
// In all subsequent
// calls, it is the last pointer
// returned by the function
{
printf("The second certificate was found. \n");
}
else
{
MyHandleError("Could not find the second certificate.");
}
//-------------------------------------------------------------------
// Add a link to the second certificate from the My store to
// the new memory store.
if(CertAddCertificateLinkToStore(
hMemoryStore, // Store handle
pDesiredCert, // Pointer to a certificate
CERT_STORE_ADD_USE_EXISTING,
NULL))
{
printf("Certificate link added to the memory store. \n");
}
else
{
MyHandleError("Could not add the certificate link to the "
"memory store.");
}
//--------------------------------------------------------------------
// Find the first certificate in the memory store.
if(pDesiredCert)
CertFreeCertificateContext(pDesiredCert);
if(pDesiredCert=CertFindCertificateInStore(
hMemoryStore,
MY_ENCODING_TYPE, // Use X509_ASN_ENCODING
0, // No dwFlags needed
CERT_FIND_SUBJECT_STR, // Find a certificate with a
// subject that matches the string
// in the next parameter
L"Insert_cert_subject_name1",// The Unicode string to be found
// in a certificate's subject
NULL)) // NULL for the first call to the
// function
// In all subsequent
// calls, it is the last pointer
// returned by the function
{
printf("The desired certificate was found in the "
"memory store. \n");
}
else
{
printf("Certificate not in the memory store.\n");
}
//-------------------------------------------------------------------
// Find the certificate link in the memory store.
if(pDesiredCert)
CertFreeCertificateContext(pDesiredCert);
if(pDesiredCert=CertFindCertificateInStore(
hMemoryStore,
MY_ENCODING_TYPE, // Use X509_ASN_ENCODING
0, // No dwFlags needed
CERT_FIND_SUBJECT_STR, // Find a certificate with a
// subject that matches the
// string in the next parameter
L"Insert_cert_subject_name1",// The Unicode string to be found
// in a certificate's subject
NULL)) // NULL for the first call to the
// function
// In all subsequent
// calls, it is the last pointer
// returned by the function
{
printf("The certificate link was found in the memory store. \n");
}
else
{
printf("The certificate link was not in the memory store.\n");
}
//-------------------------------------------------------------------
// Create a file in which to save the new store and certificate.
// Create a DACL for the file.
sa.nLength = sizeof(SECURITY_ATTRIBUTES);
sa.bInheritHandle = FALSE;
// Call the function to set the DACL. The DACL
// is set in the SECURITY_ATTRIBUTES
// lpSecurityDescriptor member.
// if !CreateMyDACL(&sa), call MyHandleError("CreateMyDACL failed.");
if(hStoreFileHandle = CreateFile(
pszFileName, // File path
GENERIC_WRITE, // Access mode
0, // Share mode
&sa, // Security
CREATE_ALWAYS, // How to create the file
FILE_ATTRIBUTE_NORMAL,
// File attributes
NULL)) // Template
{
printf("Created a new file on disk. \n");
}
else
{
MyHandleError("Could not create a file on disk.");
}
//-------------------------------------------------------------------
// hStoreFileHandle is the output file handle.
// Save the memory store and its certificate to the output file.
if( CertSaveStore(
hMemoryStore, // Store handle
0, // Encoding type not needed here
CERT_STORE_SAVE_AS_STORE,
CERT_STORE_SAVE_TO_FILE,
hStoreFileHandle, // This is the handle of an open disk file
0)) // dwFlags
// No flags needed here
{
printf("Saved the memory store to disk. \n");
}
else
{
MyHandleError("Could not save the memory store to disk.");
}
//-------------------------------------------------------------------
// Close the stores and the file. Reopen the file store,
// and check its contents.
if(hMemoryStore)
CertCloseStore(
hMemoryStore,
CERT_CLOSE_STORE_CHECK_FLAG);
if(hSystemStore)
CertCloseStore(
hSystemStore,
CERT_CLOSE_STORE_CHECK_FLAG);
if(hStoreFileHandle)
CloseHandle(hStoreFileHandle);
printf("All of the stores and files are closed. \n");
//-------------------------------------------------------------------
// Reopen the file store.
if(hMemoryStore = CertOpenStore(
CERT_STORE_PROV_FILENAME, // Store provider type
MY_ENCODING_TYPE, // If needed, use the usual
// encoding types
NULL, // Use the default HCRYPTPROV
0, // Accept the default for all
// dwFlags
L"TestStor.sto" )) // The name of an existing file
// as a Unicode string
{
printf("The file store has been reopened. \n");
}
else
{
printf("The file store could not be reopened. \n");
}
//-------------------------------------------------------------------
// Find the certificate link in the reopened file store.
if(pDesiredCert)
CertFreeCertificateContext(pDesiredCert);
if(pDesiredCert=CertFindCertificateInStore(
hMemoryStore,
MY_ENCODING_TYPE, // Use X509_ASN_ENCODING
0, // No dwFlags needed
CERT_FIND_SUBJECT_STR, // Find a certificate with a
// subject that matches the string
// in the next parameter
L"Insert_cert_subject_name1",// The Unicode string to be found
// in a certificate's subject
NULL)) // NULL for the first call to the
// function
// In all subsequent
// calls, it is the last pointer
// returned by the function
{
printf("The certificate link was found in the file store. \n");
}
else
{
printf("The certificate link was not in the file store.\n");
}
//-------------------------------------------------------------------
// Clean up memory and end.
if(pDesiredCert)
CertFreeCertificateContext(pDesiredCert);
if(hMemoryStore)
CertCloseStore(
hMemoryStore,
CERT_CLOSE_STORE_CHECK_FLAG);
if(hSystemStore)
CertCloseStore(
hSystemStore,
CERT_CLOSE_STORE_CHECK_FLAG);
if(hStoreFileHandle)
CloseHandle(hStoreFileHandle);
printf("All of the stores and files are closed. \n");
return;
} // end main
//-------------------------------------------------------------------
// This example uses the function MyHandleError, a simple error
// handling function, to print an error message and exit
// the program.
// For most applications, replace this function with one
// that does more extensive error reporting.
void MyHandleError(char *s)
{
fprintf(stderr,"An error occurred in running the program. \n");
fprintf(stderr,"%s\n",s);
fprintf(stderr, "Error number %x.\n", GetLastError());
fprintf(stderr, "Program terminating. \n");
exit(1);
} // end MyHandleError